Monthly Archives: September 2022

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Massive Acute Pulmonary Edema and Cardiogenic Shock after Scorpion Envenomation in a Young Patient with No Cardiovascular Risk Factor

DOI: 10.31038/JCCP.2022521

Abstract

Introduction: Scorpion envenomation is a common occurrence in tropical areas. There are three grades of severity. Cardiovascular complications are the most feared and condition the vital prognosis of the victim.

Observation: We report the case of scorpion envenomation that occurred in a 23-year-old young man with no cardiovascular history in the Kidal region in northern Mali. Three hours after the injection, the patient presented with massive Acute Pulmonary Edema (APO) and a state of cardiogenic shock. In intensive care at the level 2 hospital (HN2), he had received treatment based on oxygen therapy, diuretics and vasoactive amine (Dobutamine). He was then evacuated to HN3 in Dakar (Senegal). The evolution has been favorable.

Conclusion: Scorpion envenomings are serious. Cardiovascular complications condition the vital prognosis of the patient. It is a real medical race against time.

Keywords

Envenomation, Scorpion, Cardiogenic shock, Sahara-Africa

Introduction

Each year, more than one million scorpion stings and more than 3000 deaths are recorded worldwide [1-3]. Scorpion envenomation is common in tropical and sub-tropical areas. Its evolution can be serious and life threatening. Scorpion stings have a mortality rate of 1 to 2%, mainly due to cardio-respiratory failure in the absence of treatment [1-3]. We report the case of a massive acute pulmonary edema (APO) with post-scorpion sting cardiogenic shock, which occurred in a young man in Kidal (extreme north of Mali).

Observation

The victim was a 23-year-old soldier with no particular history, particularly cardiovascular, on a United Nations peacekeeping mission in the Kidal region of Mali. The scorpion sting was unique, sitting at the level of the foot and took place on May 19, 2020 at 7 p.m. It was a yellowish colored scorpion known as Leiurus quinquestriatus. The victim was taken immediately to the level 1 medical structure of his unit, he received an analgesic treatment based on Paracetamol. Three hours later, faced with the worsening of the clinical condition (confusion, agitation and profuse sisters), the victim was referred to the level 2 hospital for better care.

The rapid clinical examination on admission (H0) to intensive care at level 2 hospital (HN2), a field hospital, noted a patient covered in profuse sweating, agitated and confused with a Glasgow score of 13/15. The conjunctivae were well colored, the extremities cold, the peripheral pulses stringy, the arterial pressure (BP) impregnable. The patient was polypneic with a respiratory rate (RR) of 30 breaths per minute, oxygen saturation (SpO2) was 89% on room air. The temperature was 37.2°C. Cardiac auscultation noted tachycardia with a heart rate (HR) of 140 beats/min with a left and right gallop sound. There was no breath or friction. Lung auscultation revealed bilateral crackles reaching three-quarters of both lung fields. Locally at the level of the foot, a circumscribed inflammatory edema is observed. We concluded that there was grade 3 scorpion envenomation complicated by cardiogenic shock with massive APO. In an emergency, the victim monitored under a multi-parameter scope was placed in a semi-sitting position and received oxygen therapy with a high-concentration mask, continuous Dobutamine with an electric syringe pump (PSE), administration of a first dose of antiscorpionic serum (SAS) at the PSE, a slow vascular filling with Gelofusine 500 ml.

At (H0+20 mn), the patient presented coughing efforts with frothy pink sputum and vomiting efforts. The SpO2 was still below 90%, the FR at 30 cycles/min, the HR had increased to 151 beats/min. BP was perceived at 87/70 mmHg. We started doses of Furosemide 20 mg IVD every 10-15 min depending on SBP, administered a second dose of SAS à la (PSE), Omeprazole (40 mg), injectable Metoclopamide and Betamethasone 8 mg in intravenous. There was no extrasystole on the scope.

The electrocardiogram (Figure 1) had objectified a tachycardia at 150 beats/minute. The AP chest X-ray showed hilifuge-like fluffy opacities in “butterfly wings” disseminated in the two pulmonary fields in favor of a massive (APO) (Figure 2). A cardiac ultrasound (Fast Echo) carried out had objectified a left ventricle (LV) at 56 mm, severe global parietal hypokinesia, a restrictive mitral filling flow (E/A at 4), the systolic ejection fraction of the LV estimated at 25%, a TAPSE at 9 mm without PAH (Figure 3).

fig 1

Figure 1: Electrocardiogram performed at H0 + 10 min

fig 2

Figure 2: Chest X-ray (prone position) at H0 + 30 min

fig 3

Figure 3: Cardiac echography (Fast echo under Dobutamine) H0 + 30mn

At H0+8H we objectified a clinical improvement with disappearance of the signs of cardiogenic shock, the SBP always lower than 100 mmHg, the diuresis was 1000 ml in 8 hours. The crackles had descended to the bases of the lungs; the sounds of galloping persisted.

The tube coagulation test had objectified clots which crumbled easily after 30 minutes (coagulopathy). Serum creatinine was 21 mg. The complete blood count had objectified a hemoconcentration with a hemoglobin level of 21.8 g/dl, hematocrit at 75%, a white count at 11,700/mm3; platelets at 258,000/mm3; troponin I was positive at 3.07 ng/ml. Hepatic transaminases were: AST at 91 U/L and ALAT at 33 U/L.

We concluded that there was grade 3 scorpion envenomation complicated by cardiogenic shock with massive AO, coagulation disorders and probably functional renal failure. It is an acute myocarditis with a cardiogenic and/or lesional APO.

At H0+12H the patient is conscious cooperative, with a RR at 20 cycles/min, a saturation at 97% under oxygen, but a SBP lower than 90 mmHg under Dobutamine. He persisted with galloping noises with an HR greater than 120 beats/min. The crackles have completely disappeared.

At H0+2 p.m., the patient underwent medical evacuation under continuous oxygen therapy and Dobutamine by medicalized flights to Dakar in Senegal (level 3 health structure).

After three days (D3) of hospitalization at the Principal Hospital of Dakar, the clinical condition of the patient had improved, he had been completely weaned from Dobutamine. The cardiac ultrasound performed had objectified a ventricle with a size limit of 55 mm with a left ventricular ejection fraction of 55%. The patient was declared unfit as a precaution for the continuation of his mission in this particularly trying military theater for the organisms.

Comments

Scorpion stings are more common in tropical areas such as northern Mali where temperatures reach up to 45°C. Local populations and missionaries engaged in this area are exposed to scorpion stings [4].

In this area of the Saharan strip, the majority of stings occur during the hot period (from April to August) when the activity of the scorpion is maximum [5,6] as was the case in our patient. This would be explained by the nature of scorpions, which are thermophilic arthropods that go into hibernation at the start of the cold seasons.

Sorpionic envenomations are classified into three grades [7] depending on the severity of the systemic manifestations. In 90 to 95% of cases, the sting is limited to grade 1 local manifestations (very sharp pain and local neurological signs). Grade 2 combines hypertensive flare-ups, fever, sweats, chills, priapism, abdominal pain, vomiting, excessive sweating and marks an evolutionary turning point towards grade 3. The latter is characterized by: consciousness disorders of various depths, respiratory distress, cardiovascular shock, as in our victim. Systemic manifestations appear between the 3rd and 15th hour after the bite [7].

The active components of dangerous scorpion venom for humans are peptide neurotoxins that cause the release of mediators (cathecholamines, and acetylcholine). Stimulation of the sympathetic system leads to an adrenergic discharge responsible for tachycardia and a hypertensive attack at the beginning. On the other hand, stimulation of the parasympathetic system is at the origin of the cholinergic syndrome, hence vomiting and abdominal pain [8].

Cardiovascular failure results from 3 main mechanisms: adrenergic myocarditis occurring under the effect of a massive discharge of catecholamines, toxic myocarditis caused by direct action of the venom on the myocardial tissue and myocardial ischemia due not only to the discharge of catecholamines but also to the action of cytokines and/or neuropeptide on the coronary vessels [9-11].

Our patient presented the three characteristics of scorpion heart disease that make it original: severity (profound alteration of cardiac function), biventricular damage, and its reversibility [12]. This character increases the similarities between scorpionic cardiomyopathy and stress cardiomyopathy having as common denominator, the intense discharge of catecholamines.

APO can be mixed: cardiogenic and lesional. The mechanisms involved in cardiogenic APO are multiple [10,12]: increase in systemic BP and peripheral vascular resistance (PVR) in the first 120 minutes following the puncture, a drop in left ventricular compliance by sudden elevation of end-diastolic pressures of the left ventricle as evidenced by the restrictive filling flows in our victim.

Lesional APO is related to a direct action of the venom at the pulmonary level causing inflammation and pulmonary capillary hyperpermeability [10,13]. It is for this reason and to minimize the side effects of Scorpion Venom Antiserum that we added corticosteroid therapy to the care of our patient.

The antivenom used was Scorpion Venom Antiserum IHS® active on the venom of Androctonus amorous and Leiurus quinquestriatus. Its administration must be as soon as possible after a scorpion sting to be more effective, especially in areas where dangerous species live [14]. Unlike snake antivein serums, Scorpion Venom Antiserum is not available or accessible to our populations in the Saharan strip.

Conclusion

Scorpion stings are common in tropical Africa. Scorpion envenomation can manifest as local signs, whether or not followed by general signs. The cardio-respiratory attack constitutes the most formidable complication threatening in the short term the vital prognosis of the victim. Scorpion heart disease is biventricular, severe but reversible subject to appropriate and effective early treatment.

References

  1. Isbister GK, Bawaskar HS (2014) Scorpion Envenomation. N Engl J Med 371: 1557-1560.
  2. Dabo A, Golou G, Diarra N, Goyffon N, Doumbo O (2011) Scorpion envenoming in the North of Mali (West Africa): Epidemiological, clinical and therapeutic aspects. Toxicon 58: 154-158. [crossref]
  3. Chippaux JP, Goyffon M (2008) Epidemiology of scorpionism: a global appraisal. Acta Trop 107: 71-79. [crossref]
  4. Goyffron M, Billiald P (2007) Envenimation VI- Le scorpionisme en Afrique. Med Trop 67: 439-446.
  5. Ben Othman A, Ben Abdallah N, Aoun MB (2016) The scorpion envenomation in the region of Faouar-KEBILI at 2010-2012 : study of 421 cases. Tunis Med 94: 102-106. [crossref]
  6. Bahloul M, Chabchoub I, Chaari A, Chtara K, Kallel H, et al. (2010) Scorpion Envenomation Among Children: Clinical Manifestations and Outcome (Analysis of 685 Cases). Am J Trop Med Hyg 83: 1084-1092. [crossref]
  7. Elatrous S, Besbes-Ouanes L, Fekih Hassen M, et al. (2008) Les Envenimations Scorpionnique Graves. Med Trop 68: 359-366.
  8. Chippaux JP (2012) Emerging options for the management of scorpion stings. Drug Design, Development and Therapy 6: 165-173. [crossref]
  9. Hamouda C, Ben Salah N (2010) Envenimations scorpioniques en Tunisie. Med Emergency 5: 24-32.
  10. Bahloul M, , Regaieg K, Chabchoub I, Kammoun M, Chtara K, et al. (2017) Les envenimations scorpioniques graves: physiopathologie et rôle de l’inflammation dans la défaillance multiviscérale. Médecine et Santé Tropicales 27: 214-221.
  11. Bouaziz M, Bahloul M, Hergafi L, Kallel H, Chaari L, et al. (2006) Factors associated with pulmonary edema in severe scorpion sting patients: a multivariate analysis of 428 cases. Clin Toxicol (Phila) 44: 293-300. [crossref]
  12. Hajiba A (2015) Epidémiologie et facteurs pronostiques des envenimations scorpioniques dans le service de réanimation pédiatrique du CHU de Marrakech [Thèse]. Marrakech-Safi.
  13. Bisbahloul M, Kallel H, Rekik N, Hamida CB, Chelly H, et al. (2005) Atteinte cardiovasculaire lors d’envenimation scorpionique grave: Mécanismes et physiopathologie . La Presse Médicale 34: 115-120.
  14. Ndiaye AM, Niang C, Dembele M, et al. (2017) Envénimation scorpionique grave chez un militaire sénégalais en mission de maintien de paix au Darfour. Revue Internationale de Santé des Forces Armées 90: 79-82.

CMT-COVID Survey

DOI: 10.31038/CMCRR.2022211

Abstract

Introduction: Coronavirus disease 2019 (COVID-19) is a pandemic and public health emergency caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Our study evaluated the impact of the COVID-19 on patients with Charcot-Marie-Tooth (CMT), the most common genetic neuromuscular disorder.

Methods: A simple online questionnaire for CMT patients diagnosed with COVID-19 was developed to investigate how much the COVID-19 impacted the community of CMT patients and its consequences on the progression of CMT. With the support of the Italian CMT patient Association (ACMT-Rete) and the American CMT Association (CMTA), the survey was distributed electronically through the INC Contact Registry and the web-based Contact Registry in the US, and in Italy through the Italian CMT Registry, ACMT-Rete members newsletter and social networks.

Results: 152 individuals completed the survey. Approximately 59% of completers were female, and the average age was 49.96 (SD 12,65, range 22-76 years). 13.8% of the respondents had a COVID diagnosis and 2% (n=3) of them were health workers. Symptoms of COVID-19 were typically mild and none went to the ICU.

Discussion: These results do not show a clear increased risk of COVID in people with CMT.

Keywords

Charcot Marie Tooth, CMT, COVID-19, Survey

Introduction

Coronavirus disease 2019 (COVID-19) is a pandemic and public health emergency caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). COVID-19 symptoms include fever, cough, fatigue, shortness of breath, sore throat, headache, diarrhea, anosmia and ageusia/dysgeusia. Severe manifestations, including pneumonia, acute respiratory distress syndrome, cytokine storm, myocardial injury, and death are more common in older patients and those with medical comorbidities [1-6]. Our study evaluated the impact of the COVID-19 on patients with Charcot-Marie-Tooth (CMT), the most common inherited neuromuscular disorder [7,8]. The COVID-19 pandemic has resulted in the reorganization of health-care settings affecting clinical care delivery to patients with CMT as well as other inherited neuromuscular disorders [6,9]. How much this public health emergency has impacted the care of patients with CMT is unclear, although there is a concern that the lockdown measures impacted on patient activity [10]. There are also concerns that people with CMT and other neuromuscular diseases are at an increased risk for severe presentations of COVID-19.

We investigated how many participants in our online cohort were diagnosed with COVID-19, the symptoms they presented with, the presence of risk factors, and how the COVID-19 impacted the progression of their CMT.

Methods

The study was approved by the Institutional Review Board of the University of Iowa. A simple online questionnaire for CMT patients (Table 1) was developed to investigate how much COVID-19 impacted the community of CMT patients and its consequences on the progression of CMT. Then with the support of the Italian CMT patient Association (ACMT-Rete) and the American CMT Association (CMTA), the survey was distributed electronically through the INC Contact Registry and the web-based Contact Registry in the US, and in Italy through the Italian CMT Registry (http://www.registronmd.it/), ACMT-Rete members newsletter and social networks. In the US contact registry, 53.45% have CMT1A, 3.77% have CMT1B, 4,93% have CMT1X, 9,69% have CMT 2A and 26,19% have CMT without a subtype or genetic classification. Nearly 3500 individuals participate in the registry. All registry participants between the ages of 18 to 90 were invited and provided consent to participate in this survey. Data regarding age, gender, CMT type and if participants were health workers were collected. The CMT-COVID Survey was anonymous and included COVID-19 related questions, accessible only if the participants had both CMT and have been diagnosed with COVID-19. Participants specifically diagnosed with CMT were asked to complete the survey. The specific questions regarding COVID-19 concerned 1) symptoms from COVID-19, 2) the presence of pre-existing risk factors, 3) the presence of sleep apnea and, if so, whether CPAP or non-invasive ventilation was required, 4) if hospitalization and, if so, admission to an intensive care unit (ICU) occurred, 5) if a respirator/ventilator was required in the hospital. Demographic information on gender, age, and genetic diagnosis of the participants was obtained. Percentages were determined for all questions for each response category.

Table 1: The Survey

table 1

Results

A total of 153 patients completed the survey between May 2020 and January 2021. Approximately 59% (n=90) of responders were female, and the average age was 49.96 (SD 12.65, range 22-76 years). CMT types were represented as follows: CMT1A 46% (n=71), CMT1B 8% (n=12), CMTX1 6% (n=9), CMT2 16% (n=25), CMT4 2% (n=3), HNPP 2.6% (n=4) and 19% (n=29) did not specify the type of their CMT. Twenty-one patients (13%) had a diagnosis of COVID-19 (17 female); two of these were health workers. The remaining 124 individuals completed the survey even though they had not been diagnosed with COVID-19. Queried symptoms included fever, headache, fatigue, cough, shortness of breath, sore throat, muscular or joint pain and diarrhea (Table 2): 76% of the 21 patients (n=16) reported all symptoms, 5% (n=1) all symptoms except shortness of breath, diarrhea, and sore throat, 14% (n=3) only fever, headache, and cough, 5% (n=1) fever, headache and sore throat. Smell or taste affected 62% (n=13). We queried diabetes, COPD, asthma, and hypertension as potential risk factors: 85% (n=18) of participants had none of these risk factors, 9% (n=2) had diabetes and 5% hypertension (n=1). One also reported sleep apnea. All those with COVID-19 were evaluated by health care professionals, but none of the participants were hospitalized.

Table 2: Symptoms/Risk Factors

Symptom/Risk Factor # Responded Yes
Cough 20
Fever 21
Headache 21
Fatigue 17
Sore throat 17
Shortness of Breath 16
Muscular or joint pain 17
Diarrhea 16
No Symptoms 0
Smell and/or taste affected 13
Have Risk Factor Asthma 0
Have Risk Factor COPD 0
Have Risk Factor Diabetes 2
Have Risk Factor Hypertension 1
No Risk Factors 18
Sleep Apnea 1

Discussion

The COVID-19 pandemic impacts lives in many ways, affecting work, relationships, ability to obtain healthcare and health perception [10]. Thus, there are concerns for populations such as those with CMT as to whether they are at increased risk of contracting COVID-19 and, if they do, whether they are at risk for developing the severe complications of the disease requiring hospitalization and ICU care. Our results do not support an increased risk for patients with CMT to contract COVID-19. They also do not support an increased risk of severe complications from the disease if individuals are infected with SARS-CoV-2. We recognize limitations with our study in that our data comes from individuals we have not examined who have been asked to complete on-line surveys. In fact, we only asked those who had been diagnosed with COVID-19 to respond to the survey, those who died could obviously not have completed the survey. The fact that many (132/153) completed the survey but only around 21 people with CMT actually had acquired COVID simply means that over 100 of the responders had not carefully read the instructions. Therefore, it raises questions about the actual percentages of patients with CMT and COVID-19 which is likely to be much less than the 13% of the CMT population cited here. However, we believe that our results suggest that there is not likely to be an increased risk of acquiring severe cases of COVID-19 for most patients with CMT. In part this is based on the fact that in past queries of our USA and Italian registries there are typically hundreds of patients who rapidly respond to our questionnaires. Thus, we think it unlikely that there were many patients in the registries who had COVID-19 but simply did not complete the questionnaires and that those that did acquire COVID were not more severely affected clinically than people without CMT based on the responses to queries about disease severity. We reasonably conclude that COVID infection is not common in the CMT patient population. Whether there are increased risks for patients with rarer forms of CMT with significant respiratory compromise remains unanswered and will require investigations focusing on these subgroups. We recognize the need for health professionals to increase efforts to carefully follow individuals with CMT to determine which if any CMT subtypes or symptoms are particularly predisposed to develop more severe forms of disease.

Acknowledgements

The authors thank the Inherited Neuropathy Consortium, the Italian CMT Network, Charcot Marie Tooth Association (CMTA), ACMT-Rete per la malattia di Charcot-Marie-Tooth OdV and the Associazione del Registro per le Malattie Neuromuscolari (http://www.registronmd.it/). Research reported in this publication was supported by a grant for the project from the CMTA in addition to funding from the National Center for Advancing Translational Sciences of the National Institutes of Health under Award Number UL1TR002537. MES receives support from the NCATS and the NIH (U54NS065712), NINDS (R21TR003034; U01 NS1094301, R01NS105755), the MDA and the Charcot Marie Tooth Association. RZ, CP and DP are members of the European Reference Network for Rare Neuromuscular Diseases (ERN EURO-NMD). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. The Italian CMT Network includes drs. Lucio Santoro, Fiore Manganelli, Stefano Tozza, Gian Maria Fabrizi, Tiziana Cavallaro, Marina Grandis, Stefano C. Previtali, Isabella Allegri, Luca Padua, Costanza Pazzaglia, Aldo Quattrone, Paola Valentino, Massimo Russo, Anna Mazzeo, Giuseppe Vita.

Ethical Publication Statement

We confirm that we have read the Journal’s position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.

Author Contributions

Riccardo Zuccarino, study concept and design, analysis and interpretation of data, drafting and critical revision of manuscript for intellectual content Chiara Pisciotta, statistical analysis and interpretation of data, critical revision of manuscript for intellectual content Valeria Prada, statistical analysis and interpretation of data, critical revision of manuscript for intellectual content Filippo Genovese, study concept and design, interpretation of data, critical revision of manuscript for intellectual content Amy Gray, interpretation of data, critical revision of manuscript for intellectual content. Angelo Schenone, study concept and design, analysis and interpretation of data, critical revision of manuscript for intellectual content Davide Pareyson, study concept and design, analysis and interpretation of data, critical revision of manuscript for intellectual content Michael E. Shy, study concept and design, analysis and interpretation of data, critical revision of manuscript for intellectual content

Author Disclosures

None of the authors has any conflict of interest to disclose.

References

  1. Du W, Yu J, Wang H, Zhang X, Zhang S, et al. (2020) Clinical characteristics of COVID-19 in children compared with adults in Shandong Province, China. Infection 48: 445-452. [crossref]
  2. Gou FX, Zhang XS, Yao JX, Yu DS, Wei KF, et al. (2020) Epidemiological characteristics of COVID-19 in Gansu province [in Chinese]. Zhonghua Liu Xing Bing Xue Za Zhi 41: E032. [crossref]
  3. Jeng MJ (2020) COVID-19 in children: current status. J Chin Med Assoc 83: 527-533. https://doi.org/10.1097/JCMA.0000000000000323.
  4. Wan S, Xiang Y, Fang W, Zheng Y, Li B, et al. (2020) Clinical features and treatment of COVID-19 patients in northeast Chongqing. J Med Virol 92: 797-806. [crossref]
  5. Zheng Y, Xu H, Yang M, Zeng Y, Chen H, et al. (2020) Epidemiological characteristics and clini- cal features of 32 critical and 67 noncritical cases of COVID-19 in Chengdu. J Clin Virol 127: 104366. [crossref]
  6. Veerapandiyan A, Wagner KR, Apkon S, McDonald CM, Mathews KD, et al. (2020) The care of patients with Duchenne, Becker, and other muscular dystrophies in the COVID-19 pandemic. Muscle Nerve 62: 41-45. [crossref]
  7. Reilly MM, Murphy SM, Laura M (2011) Charcot-Marie-Tooth disease. J Periph Nerv Syst 16:1–14.
  8. Gentile L, Russo M, Fabrizi GM, Taioli F, Ferrarini M, et al. (2020) Charcot-Marie-Tooth disease: experience from a large Italian tertiary neuromuscular center. Neurol Sci 41: 1239-1243. [crossref]
  9. Veerapandiyan A, Connolly AM, Finkel RS, Arya K, Mathews KD, et al. (2020) Spinal muscular atrophy care in the COVID‐19 pandemic era. Muscle Nerve 62: 46-49. [crossref]
  10. Prada V, Hamedani M, Genovese F, Zuppa A, Benedetti L, et al. (2020) People with Charcot-Marie-Tooth disease and COVID-19: Impaired physical conditions due to the lockdown. An International cross-sectional survey. Ann Phys Rehabil Med 63: 557-559. [crossref]
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Concern with Aging: A Mind Genomics Cartography

DOI: 10.31038/ASMHS.2022654

Abstract

98 respondents each evaluated unique sets of 60 vignettes, combinations of messages created from a base set of 36 different messages. These messages dealt with the reaction to aging. Respondents rated the vignettes in terms of the anxiety specifically about aging that the vignette provoked, using an anchored 9-point scale (1=Can deal with it … 9=Cannot deal with it). Transformation to a binary scale and then analysis by regression revealed that the greatest sources of anxiety came from three different messages dealing with different aspects (living in an old age home, treatment by a plastic surgeon, reliance on one’s employer). These three messages were strong performers for virtually all groups, although for groups defined by geo-demographic other messages occasionally emerged as strong, but in an inconsistent manner. Three mind-sets emerged, but were not radically distinct from each other, suggesting that when people think about age they think about the cluster of above-mentioned issues, viz.,  loss of independence (living in an old age home), loss of physicality (plastic surgeon), and betrayal (one’s own company).

Introduction

The ongoing advancement of medicine and a newfound focus on a healthier lifestyle has allowed us to live longer, but not without consequences. The issue of ‘aging’ is becoming increasingly important. The popular press is filled with the repercussions of getting older reflected in stories from individuals and their linkage with the issues of aging. The increase in the number of senior residences, retirement homes, and at-home care further portrays tangible evidence of the growing aging population as these are being built to reflect the demand for these services.

As a society, we are well aware of the issue of aging, ranging from the practical worries about one’s health, one’s mobility in daily life, the loss of loved ones, and the host of legal issues which require attention for the orderly transfer of one’s estate [1-3]. To offset these anxieties, we often see the aging population utilizing plastic surgery, dyeing their hair, or not associating with other elderly people to hide the fact that they are ‘getting old’ (https://journals.sagepub.com/doi/pdf/10.2190/1U69-9AU2-V6LH-9Y1L). The aging population often also refuses retirement homes or senior community living to feel independent from others their age who are aging too. When confronted with no other option but to accept the inevitable, elderly individuals that are subjected to assisted living often face higher levels of anxiety about aging [3].

If these worries are not enough, there are the nagging expected but dreaded major events on the road to aging, often manifested in jokes among friends, jokes which attempt to defuse the grimness of getting old. With this, the stereotype of ‘getting old’ begins early on and, if accepted, leads to higher anxiety about aging later in life. These jokes may seem harmless but can lead to serious consequences [2].

Mental health issues in the elderly population are real and often overlooked. With social media and mental health awareness coinciding, the spotlight on mental health issues often falls on the youth. The aging population, whether it be due to fear, inability or stubbornness, often lacks access to social media and therefore many mental health resources. The mental health crisis for the elderly may seem minimal, but studies show it is present and neglected. As one’s physical health begins to deteriorate, their mental health is at risk of following quickly. The anxieties about aging can be life-threatening leading to, in extreme but not uncommonly death by suicide https://jamanetwork.com/journals/jamainternalmedicine/article-abstract/217074). Although a universal problem, it is important to note that  the levels of anxiety about aging differs based on qualities such as race, gender, age, sexual orientation, and socioeconomic status [1,4,5].

There is significant popular press on the issues of getting old, these topics becoming more frequent over the past ten years. One need only look at the number of articles on ‘aging’ using Google® as a measure to demonstrate this increasing frequency. As of this writing (July, 2022), Google® reported 103 million hits or sites (July, 2022). The Google® list is led by the scientific definition of anxiety about aging, gerascophobia, taken from the Wikipedia article:

Gerascophobia is a clinical phobia generally classified under specific phobias or fears of a single specific panic trigger. Gerascophobia may be based on anxieties of being left alone without resources and incapable of caring for oneself due to age-caused disability]

Due to humans being mortality salient, sufferers will often feel as though aging is the first sign that their immune systems are starting to weaken, making them more vulnerable and prone to diseases… Some sufferers seek plastic surgery to make them look more youthful while the main concern of others is a fear of internal, biological long-term damage caused by the aging process.

Source: https://en.wikipedia.org/wiki/Gerascophobia

The Mind Genomics Approach to the Way People Think

A great number of the published studies on aging deal with the nature of the fear, its causes, manifestations, and suggestions about how to reduce it.  The studies in the scientific literature focus on the nature of anxiety about aging [2,4,6], its manifestations [7] and the construction of scales to measure anxiety [5].  The papers published paint a rich picture but can be augmented by other research approaches with a history founded in consumer research. We present one way, using Mind Genomics.

During the past forty years, the emerging science of Mind Genomics has attempted to understand the way people respond to the information of everyday life.  Our daily lives are filled with situations which cause angst and discomfort, as well as being filled with situations which do the exact opposite, bring us joy.  How can we quantify the experience of everyday life, merging the richness of experience and the discipline of quantitative science?  And, to go one step further, how can we create a living ‘database’ about the features of everyday experience, a database that can be used to study differences among people, among situations, and over time?

Mind Genomics was designed with the foregoing vision in mind.  When studying people over the past century, psychologists have been able to understand a person as an individual or a small group of individuals acting together. This is known as the idiographic approach, studying the person (or small group) in detail. The information obtained is deep, but not scalable, not general, and usually not quantitative.  Psychologists have also studied people in larger groups, using the nomothetic approach, looking for general laws of group and individual behaviors.  It is from these roots in psychology that Mind Genomics emerged.

One can trace the evolution of Mind Genomics, and its application in this specific paper on aging, to three different sciences/disciplines: consumer behavior, psychophysics (a branch of experimental psychology), and statistical model building, respectively. Together, in this emerging science of Mind Genomics, these three disciplines shed light on motives and drivers of human behavior, doing so in a way which invites experimental science to contribute, and which allows a rich database of information to be created, and continually updated in a cost-effective, rapid, and scalable fashion.

Psychophysics is the branch of experimental psychology interested in the relation between stimuli and perceptions. It is from psychophysics that we learn how to quantify perceptions, such as the sweetness of different concentrations of sugar dissolved in water. The founder of modern-day psychophysics, S.S. Stevens of Harvard University, called this effort ‘outer psychophysics,’ because the effort was to measure the subjective magnitude of a physically-measurable stimulus, e.g., the aforementioned sweetness of different concentrations of sugar solutions.  Mind Genomics uses somewhat similar methods to measure the intensity of ‘thoughts, which are not physically measurable, but which are real.  This is the so-called ‘inner psychophysics’ of Stevens ([8], personal communication).  It is important to note that the research does not use physiological measures of body reactions, such as EEG (brain waves), GSR (skin resistance, the galvanic skin response), eyeblink, and so forth.  We may summarize the contribution of psychophysics to Mind Genomics as the objective to quantify experience at the conscious, rational level.

Consumer Research is a growing branch of applied science, focusing on how people make decisions about the practical world of daily life. The emphasis here is on ‘practical’ and ‘daily.’  For example, how do people trade-off different features of products, knowing that they cannot afford all of them? For products, what is important, what is not important.  Is there a willingness to pay more for items that one likes? And, of course, when we read information about something and react to that information, can we be said to follow one of several different patterns of behavior?  Consumer behavior lies at the nexus of applied psychology, marketing research, sociology, behavioral economics and other social sciences.  It is from consumer research that Mind Genomics takes the approach of testing combinations of stimuli, combinations that present scenarios, situations, rather than testing one idea at a time.  Names such as Paul Green and Jerry Wind at Wharton School of Business at the University of Pennsylvania deserve mention here for their population of these approaches [9], along with Norman Anderson who did similar types of investigations, calling the approach ‘functional measurement’ [10].

Our final area of foundational work comes from the world of statistics, and specifically the efforts of those who create experimental designs [11]. These designs are specified combinations of factors, set up so that the respondent evaluates the combinations in a way that the evaluation of a number of such combinations allows it to become possible to deconstruct the rating to the part-worth contribution of each element of the set originally combined.  In other words, the world-view of psychology and consumer research, that the measurement should be taken on the combination of factors, is delivered through statistics, through the experimental design. It takes only the effort to combine the independent variables into combinations, so-called vignettes, and have the respondent test the vignettes, that Mind Genomics can actually measure the cognitive response to ideas, the inner psychophysics, in a far less biased, more effective way.

The Mind Genomics Paradigm Applied to the Personal Experience of Anxiety

The Mind Genomics paradigm has been worked out and simplified over the past thirty years. The approach uses an underlying experimental design, in which the research begins with a single topic, asks a series of questions which ‘tell a story,’ and for each question creates a set of answers, ‘elements’. The Mind Genomics approach has been used extensively for a variety of topics, ranging from studying response to objects (e.g., foods; [12]) to situations [13], and even to the law [14], and health [15].

The experimental designs used by Mind Genomics are created to possess the following critical properties:

Basic Approach

Mind Genomics ‘works’ by combining phrases, presenting these combinations (called vignettes) to respondents, getting the reaction to the combinations from a respondent, and then deconstructing the responses to the contribution of the individual elements.  All of this is controlled by an underlying structure called the experimental design.

The Basic Design

The experimental design for the study calls for 60 vignettes, each element appearing five times and absent 55 times. Furthermore, ‘doing the math’ shows that each question, with nine answers, ends up contributing to 45 of the 60 vignettes, and thus by design is absent from 15 of the 60 vignettes.  The absence of elements is controlled by the design, producing mainly vignettes comprising four answers (one from each question) but also vignettes comprising three answers, and vignettes comprising two answers. In no case are there vignettes comprising only one answer.  The statistical benefit of working with incomplete vignettes of 2-3 elements, along with complete vignettes of four elements is that the structure avoids statistical multi-collinearity, where knowing the status of 8 answers to a question (vignette) automatically determines the status of the ninth element. Were that to be the case, the regression modeling would fail.

Permutation

The experimental design is a structure whose form is maintained, but the specific elements can be permuted, as long as the element does not change the question that it answers.  This permuted design means that the same element can one time be ‘A1” but another time ‘A2’, and a third time ‘A3’, etc. As a result, the vignettes evaluated by one respondent will be different from the vignettes evaluated by another respondent. The benefit is that the researcher can use Mind Genomics to ‘explore’ the topic, rather than select a limited, specific set of combinations [16].

Different-size, Often Incomplete Vignettes, Allowing for More Powerful Regression Analysis

The vignettes are small but of different sizes. The underlying experimental design specifies which particular elements are combined in a vignette.  Typically, the vignettes comprise as few as two elements, and as many as four elements (or in some designs five elements). The underlying experimental design ensures that the elements are statistically independent of each other. The design also ensures that the data from each individual respondent can be analyzed without reference to any other data in the study. This is called a ‘within subjects’ design.

For the data set we explore (Aging, in the Deal with It! study) we use an experimental design comprising four questions, each question with nine answers (36 elements). The elements were combined by the underlying design into a total of 60 different vignettes, each element appearing five times and absent 55 times from the 60 vignettes.  Although the design is permuted, no element (answer to one of the four questions) is allowed to change the question that it is answering. That is, an element can start as A1, be permuted to A2, or A8, but never jump into the B, C, or D questions.

This study on aging comes from a set of parallel studies run in 2003, called the It! Studies [17]. The objective of the studies was to create a database about reactions to common products or events, with each topic covered by one study. The earliest studies dealt with food and beverages (Crave It!, Drink It!, Good for You!). The later set of studies, run a year or two later, dealt with shopping (Buy !), with insurance (Protect It!), and finally with topics likely to cause anxiety (Deal With It!; [18]).

The study on anxiety and aging with it was one of 15 different studies, as shown in Figure 1.

The topics of these It! studies were open to respondents recruited by an online panel provider, Open Venue Ltd., in Toronto, which provided US respondents.  The respondents were invited to the study by email containing an embedded link. The wall showed the respondents the 15 different studies. Respondents chose the study which interested them or simply deleted the invitation.  In contrast to the typical studies in the It! series, viz., those dealing with pleasant subjects like food, beverages, shopping, etc., where the studies ‘fill’ rapidly and disappear from the wall in Figure 1, those studies in the Deal With It! series took an unusually long time to reach 100 respondents, often more than a week. Furthermore, a large number of respondents dropped out of these studies because of the unpleasant nature of the topic. The dropout rate often exceeded 50%, a very unusual number.

fig 1

Figure 1: The 15 different studies in the Deal With It! Project

Table 1 presents a screenshot of the structure of the invitation as would be sent to the respondents. The invitation provides enough information about the study to engage respondents who are interested, but has no information about what might be an ‘appropriate answer.’ The invitation provides information about the length of time (15-20 minutes), and about the incentive (a drawing for money prizes).

Table 1: The draft version of the invitation to be sent to respondents.

table 1

The Raw Materials for the Study

Table 2 presents the elements and the rationale for the elements. The driving force in the It! studies was to create a series of elements which represented different aspects of anxiety. Since the It! studies were to deal with 15 different topics, the elements were slightly modified by topic (e.g., aging vs obesity) in order to make ‘sense’  The elements were kept as parallel as possible across all 15 studies.  The language of the element was made as colloquial as possible while maintaining clarity. Finally, some of the elements presented the information as a description, other elements presented the information as if one were talking to oneself, or describing one’s emotions to another, but always from the point of a third person.

The 36 elements or answers in Table 2 fall by design into four groups, four questions. The purpose of the question is to drive the answer, to make sure that the answer ‘fits’ the question. In the end, however, the question itself is only a bookkeeping device, to make sure that the question does not generate answers which ‘don’t belong’. That bookkeeping property, to keep the ‘meanings’ straight, means that two or more different answers, statements which are of the same type but convey mutually contradictory information, will never appear in the same vignette.  The respondent need not see the questions. Only the response to the answers is important because that is where the relevant information lives.

Table 2: The four questions, the nine answers to each question, and the rationale for each element. The respondent never saw the rationale for the element, but only the element itself.

table 2

The actual interview required about 15-17 minutes. The interview was structured, beginning with the introduction to the topic shown in Table 1, followed by the presentation of 60 vignettes. The vignettes were absolutely different from one respondent to another, ensured by the ‘permutation’ of the basic experimental design. Finally, the respondent completed an extensive self-profiling  questionnaire shown in Table 3.  The self-profiling questionnaire will permit the correlation between how the respondent describes herself/him and the pattern of reactions to the elements.

Table 3: The self-profiling questionnaire

table 3(1)

table 3(2)

table 3(3)

It is important to emphasize that the respondent cannot possibly ‘game’ the Mind Genomics system, simply because the elements are presented in groups of two, three, and four, respectively, in a way which seems utterly ‘random’ to most respondents. Indeed, when respondents describe their feelings about the study, doing so after the fact in follow-up contacts, many say that they feel that their answers are totally random, and they are guessing

Data Transformation at the Level of the Individual Respondent

A key benefit of Mind Genomics is the ability to create an individual-level model relating the presence/absence of the 36 elements to the ratings or to transforms of the ratings.  The responses themselves may either be the original 1-9 rating or, more typically in Mind Genomics studies, a transform of the 1-9 scale.  The transform changes ratings of 1-6 to 0, and ratings of 7-9 to 100, and afterwards adds a vanishingly small random number to each transformed number. The rationale for doing that is to prevent all 60 ratings from one respondent to be transformed into either 0 (in the case where all ratings lay between 1 and 6), or 100 in the case where all ratings lay between 7 and 9). The vanishingly small random number ensures that the transformed rating has some marginal degree of variability, allowing the OLS (ordinary least-squares) regression to work.

The scientific rationale for the conversion to a binary scale is that very few people really understand what the scale values actually mean. Thus, the typical manager will ask for clarification of the data, when all that is needed is an explanation of what the presented averages ‘really mean!. According to S.S. Stevens, the aforementioned founder of modern-day psychophysics, the hardest thing in science is to move from a continuous function to a discontinuous function, viz., to chop a continuum into meaningful components.

After the conversion is made, the data from each respondent is subject to the statistical procedure of OLS (ordinary least=squares regression), colloquially called ‘curve fitting’ [19]. The objective is to deconstruct the transformed ratings for a given respondent to the contribution of each of the 36 elements. Recall that each respondent rated 60 unique vignettes and that the 36 elements were combined in ways that ensured that the elements would be statistically ‘independent of each other. This effort pays out handsomely, allowing the regression model to describe the relation between the elements and the ratings by the equation:  Binary Rating = k0 + k1(A1) + k2(A2) … k36(D9).

This simple equation, estimated separately for each respondent, produces a matrix of data, one row for each respondent. Each row in the matrix comprises the additive constant, followed by 36 columns of numbers, each column corresponding to one of the 36 elements.  The coefficients tell us the estimated contribution of each element to the binary transformed rating.  One can imagine this column of data multiplied 98 times, to create 98 rows of data, one row for each of the 98 respondents who participated.

Table 4 shows the output of the regression modeling for three respondents, #1,#2 and #3, respectively. The model features an additive constant (estimated binary transformed rating in the absence of elements, a purely theoretical parameter, but a good baseline), and then 36 rows, one row per coefficient.  Table 4 is ‘transposed,’ so that the rows correspond to the 36 elements. The transposition from row to column is made simply to show the large table in an easy-to-read format.

Table 4: Example of coefficients for three respondents< #1, #2, #3, emerging from individual-level regression, and the recoding of those coefficients (0 unless coefficient is greater than 8, in which case it is transformed to 100).

table 4

Statistical analysis of the modeling suggests that coefficients of +8 or higher are ‘statistically’ significant, viz., that they are probably not 0. In view of that, we end up learning more by ‘taming’ the wide range of coefficients. The taming consists of replacing all coefficients of 8 or higher by 100 to show that the element drives anxiety (cannot deal with it, viz., rating of 7-9). The transform further replaces all coefficients lower than 8 by 0, to show that the element does not drive anxiety (rating of 1-6 on the 9-point scale, the region where the respondent feels that the vignette does not drive the feeling of anxiety).  In Table 4 the original coefficients for respondents 1-3 are labelled R#1, R#2 and R#3. In turn the transformed coefficients for the same three respondents are shown to the right, and labelled TR#1, TR#2, and TR#3, respectively.  The elements are now renamed to be XA1, to denote that numbers associated with them are the newly transformed 0/100. The foregoing may seem to be a great deal of work, but the analysis will show the patterns far more easily.

Results

We begin with the average transformed coefficients from the total sample of 98 respondents (Table 5). For the total panel, we look at all 36 coefficients, as well as the additive constant, which was not transformed.  The additive constant is 28, meaning that in the absence of anything else except knowing the topic is ‘aging,’ 28% of the respondents would rate a vignette 7-9.  All vignettes comprised 2-4 elements by design, so the additive constant is an estimated parameter.

It is the averages of the transformed coefficients which are of major interest.  In Table 5, as well as in the other tables of averages, those elements are shaded which generate a value of 50 or higher. This cut-off means that across all 98 respondents, 50% or more generate coefficients of +8 or higher for a specific element. We would conclude that this element drives anxiety.

Table 5: The averages of the transformed coefficients for the total panel. The 36 coefficients are sorted in descending order. Averages of 50 or higher are shaded.

table 5

The averaging suggests three major worries:

a. Living in an old age home (viz., loss of independence)

b. You believe Charities will help you get through this (viz., loss of economic independence)

c. You believe your plastic surgeon you have will help you get through this (loss of attractiveness and vitality).

Table 5 suggests that there are some common, but not necessarily universal fears about aging. What is remarkable is that these fears ‘make sense’ and are easy to interpret, even though as noted above, the vignettes seem to be, in the words of Harvard psychologist William James, a ‘blooming, buzzing confusion’, leaving respondents feeling that they were just guessing when their data seems quite reasonable, at least in terms of the average.

Creating Easier to Read Tables of Data

Mind Genomics studies generate large tables of data, especially when the elements are ‘cognitively meaningful’ in and of themselves, rather than being points which make sense only in patterns. With Mind Genomics the individual elements carry with the richness of experience and an invitation to reflection and explanation.

The early Mind Genomics studies, of which this study is an example, comprise four questions, nine answers, and thus 36 elements. Thus, each subgroup to be considered generates 36 averages. That amount of data overwhelms, becoming a ‘wall of numbers.’  The way out of the quandary is to eliminate all data with averages less than 50 and to eliminate all elements which fail to generate an average of 50 for at least one subgroup. This first step, pruning, shortens the data tables, making the patterns easier to discern.

The second step ranks the elements and ranks the subgroups, both in descending order, so that the top element is the one with the strongest performance across the different subgroups (called Row Sum), and the strongest subgroup (is the one with the strongest performance across the different elements (called Column Sum). These two statistics, row sum and column sum allow the strong performing elements to emerge. The pattern is easy to identify since the only data in the table are averages of 50 or higher.

Differences by ‘Time of Day’?

The first question in the self-profiling questionnaire was the time of day in two hour sections. Although we don’t typically think of studies as influenced by when the respondent participated, part of the issue with the Deal With It! series was to search for deep, hitherto unexplored effects.  Following the approach described above, Table 6 shows the strong performing elements by time of day.

Table 6: Average transformed coefficients by ‘time of day’. On strong performing averages of 50 or higher across the appropriate respondents appear in the table.

table 6

The first thing to notice about the data in Table 6 is that there are only five elements. One element is ‘living in an old age home…’, which will reappear in analysis after analysis. The other four strong performing elements are the response to statements that others (e.g., Charities) ‘will help you get through this.’ Clearly, relying on a second party outside of one’s control causes anxiety, even though the statement is meant to be a statement that there is someone else to help.

The second thing to notice is that the respondents who participate in the evening show far greater anxiety, whereas the respondents who participate in the afternoon and the morning show far less anxiety. We see that from the column sums of strong performing coefficients (468 for evening, 126 for afternoon, and only 54 for morning.

Finally, the additive constant from the original, untransformed model, average around 25-33, suggesting a low predisposition for an anxious response. Recall that the additive constant is an estimated parameter that shows the percent of responses 7-9 to be expected in the absence of elements. In other words, the additive constant is an estimated baseline.

Differences by WHO the Person is (Gender, Age, Income, Where the Person Lives)

The extended self-profiling classification shown in Table 3 allows us to learn a lot about who the respondent is.  The questions, ranging from gender to age, income, and even neighborhood, may produce some new insights into what concerns the respondent. With that in mind, we now look at Tables 7-10.

Gender (Table 7): The respondents comprised primarily females, a distribution which often is corrected for by oversampling males until a balance is reached. In the It! studies, starting back in 2001 and continuing until 2004 for all of the It! studies, no effort was made to balance the genders. With 15 studies in the Deal With It! project, and with a limited budget, gender balancing might be laudable but unaffordable.

Table 7 shows the strong performing elements. Both males and females begin with modest basic anxiety (additive constant 31 vs 28, based on the original model, before transformation).  It is when we get to the performance of the specific elements that we see the dramatic gender differences.  The one element which makes both males and females very nervous is XA9, living in an old age home, with the value for the males 83, and the values for the females 56. We interpret that to mean that 83% of the males feel that living in an old age home is something with which they could not deal. Females were less responsive, with a coefficient of 45, meaning 56% of the females respond that they could not deal with it. Keep in mind once again that the respondents were not directly asked about living in an old age home, but rather than element was part of a set of 2-4 elements combined into a vignette.

Table 7: Average transformed coefficients by ‘gender’. On strong performing averages of 50 or higher across the appropriate respondents appear in the table.

table 7

Table 8 shows the strong performing elements by age.  The columns are arranged by age, rather than by column sum to allow any age-related pattern to emerge.  Once again we see the same three elements emerging as most anxiety provoking (living in an old age hold, help from charities, help by plastic surgeon) The one major new entry, not surprisingly, is the response from the older respondents (age 61+) who are most frightened when they read ‘You believe your company will help you get through this.’ Their strong response to this element, even twenty years in 2003, suggests that older people near or past retirement are insecure and nervous when they think of their companies as providing any help to older employees or former employees.

Table 8: Average transformed coefficients by ‘age’. On strong performing averages of 50 or higher across the appropriate respondents appear in the table.

table 8

Income tells the same story as age, as shown in Table 9.

Table 9: Average transformed coefficients by ‘income’. On strong performing averages of 50 or higher across the appropriate respondents appear in the table.

table 9

Respondents selected the type of neighborhood in which they lived. Table 10 shows that there is a great disparity in the distribution of the strong responses by neighborhood. Those respondents identifying themselves as living in a city, but a suburban (residential) area in the city showed the greatest number of elements which drove anxiety.

Table 10: Average transformed coefficients by ‘type of neighborhood in which the respondent resides’. Only strong performing averages of 50 or higher across the appropriate respondents appear in the table.

table 10

When we look at the data more deeply, however, we find that the strong performance is due to a few anomalies. These elements drive anxiety for only one or two groups of respondents

  1. You believe your company will help you get through this -Suburban area, Rural
  2. You believe your Local Hospital will get you through this – Suburban area, Small suburb
  3. The media talking about how hard it is to get old… – Suburban area
  4. Your body doesn’t do what it used to be able to do when you were younger… – Suburban area
  5. You’d drive any distance to get away from it… Suburban area
  6. You experience it in all your senses… Suburban area

If we discount these six elements are relevant to one subgroup, or at most two, we end up with the same elements which are responsible for the strongest anxiety, namely charities, plastic surgeon, and old age home.

Is There a Relation between What a Respondent ‘Feels’ and the Pattern of Elements Which Drive Anxiety?

Question 6 of the self-profiling questionnaire asked the respondent to introspect about how she or he feels and check all the emotions on a list which apply.  The question did not attempt to link the feelings to the vignettes because the respondent had just evaluated 60 vignettes. Nonetheless, it is instructive to look at the covariation between what a respondent selects as anxiety product (rating 7-9) and what feelings the study leaves with the respondents.

Table 11 shows the table, once again in the standard format. The dynamics of the data remain generally the same. That is, there are the three major aspects driving anxiety (charities, plastic surgeon and old age home, respectively). These generate the highest sum for the three most negative feelings (frustrated, depressed, bored). The other two elements which co-vary most strongly with these emotions deal with the local hospital and one’s own company. Based upon the data from the previous analyses, these strong performing elements do not surprise. Four of the elements deal with being helped, when one needs help (charities, plastic surgeon, hospital, one’s own company). There is once again a sense of being frightened that these presumed ‘allies in life’ will prove actually impotent, or unwilling to help. The fifth one, old age home, speaks to a sense of helplessness.

The right side of Table 11 shows the selected emotions with the lowest column sums, viz., the lowest degree of causing anxiety across the 36 elements. These four emotions/feelings, from the lowest up, happy, optimistic, energetic, and relaxed, four positive emotions. The elements which drive anxiety for people reporting these emotions are the ones that we have to come to expect, namely charities, plastic surgeon and old age home.

Table 11: Average transformed coefficients by selection of up to three emotions experienced by the respondent after having evaluated 60 vignettes. Only strong performing averages of 50 or higher across the appropriate respondents appear in the table.

table 11

The ability to cross-reference one’s selected emotions at a given time with the elements driving anxiety creates a new opportunity for Mind Genomics. There is now the possibility of looking at the covariation of emotions and anxiety producers, in a situation where the respondent cannot possibly ‘game’ the system.

Deconstructing the Respondents into Mind-sets Based Upon the Pattern of the Coefficients

A hallmark of Mind Genomics is the ability to cluster the respondents into different groups, so-called mind-sets, based upon the pattern of coefficients. Clustering is a well-defined class of statistical processes which divide a group of objects (e.g., people) into non-overlapping groups, based upon the pattern of measures [20]. For our study clustering is done by dividing our 98 respondents into two and then into three groups, clusters, viz., mind-sets, based upon the pattern of their 36 coefficients.

The regression analysis already provides us with the additive constant and the 36 coefficients for each of our 98 respondents. This within-subjects modeling is feasible because each respondent evaluate the precise combinations needed to create a linear regression equation relating the presence/absence of the 36 elements to the binary transformed response.  The 36 estimated coefficients from the individual-level OLS (ordinary least squares) become the 36 variables on which the k-means clustering is done. The analysis created two and then three clusters, or mind-sets, creating them by assigning each of the 98 respondents to one of the three non-overlapping cluster.

Table 12 shows the results for the two and three mind-sets. To maintain consistency, the mind-sets were created using the estimated coefficients emerging from regression. Afterwards, the coefficients were once again transformed, so that coefficients of 8 or higher were transformed to 100, coefficients below 8 were transformed to 0. In short, the clustering into mind-sets produces new subgroups, not based on who they say they are or what they feel, but rather based on how they respond to the different statements. The power of clustering is that it puts together people with similar points of view, and in effect gets rid of the extraneous material which may seem relevant but is not. As a consequence, the mind-sets are a great deal more focused with almost no extraneous elements.

Table 12: Average transformed coefficients by two and three emergent mind-sets resulting from k-means clustering. Only strong performing averages of 50 or higher across the appropriate respondents appear in the table.

table 12

Based upon the strong performing elements we may offer these names to the mid-sets (MS)>

Two mind-sets:

MS 1 of 2 – Betrayal – Worry about being let down by one’s own company

MS 2 of 2 – Loss of freedom – Worry about living in an old age home

Three mind-sets:

MS 1 of 3 –  Betrayal – Worry about being let down by one’s own company

MS 2 of 3 –  Betrayal and Beauty – Worry about being let down by one’s own company AND gaining weight

MS 3 of 3 – Loss of freedom – Worry about living in an old age home

Discussion and Conclusion

The use of a combination of elements (vignettes) and the use of different combinations (‘permutations)’ scheme deserve their own notes because of the contribution that they make to science. In attitude and consumer research quite often the respondent is biased, either with awareness (viz., getting it right) or without awareness. Researchers have been aware of the biases involved when respondents feel that there is an expectation for them to be consistent, or for them to give the right answer, for whatever reason.  Allowing the respondent to answer questions one by one gives the respondent a chance to reframe the criterion each time, to be appropriate to the question. The typical researcher may not even realize that the respondent is reframing, changing the criterion, given the right answer for some questions, and the true answer to others. One need only work with dietitians who, upon working with the client for the first and doing the ‘intake’ find the client to report being a model citizen with no ‘bad stuff’ in the house. That is the ‘correct’ answer, which should make the dietitian happy. Inspection of the house will reveal lots of foods which are never reported, overlooked.  The use of vignettes prevents some of this changing criterion to always give the right answer. To once again quote the words of Harvard psychologist Wm James, the vignettes present a ‘blooming, buzzing confusion’ to the respondent. It is simply impossible with these 2-4 element vignettes to know what is the ‘right answer’. Most respondents end up guessing, or feel that they are guessing. Yet their data suggest just the opposite, viz., that they are consistent, but relaxed, maybe even bored.

The second topic is the permutation. Typically, science works by choosing a promising area, testing in that area, and reducing the error of measurement by making many measurements of the same area. The ingoing but unspoken assumption is that this area is the ‘correct’ area, such assumption rarely eally questioned in terms of its validity because the effort to replicate is too difficult, expensive, and of course discouraging. In the meanwhile, no matter how the area is discovered, usually by prior knowledge and good guesswork, the researcher ends up shoring up the measurement of perhaps a wrong area by reducing the error of measurement. The reduction, not so much by exploring other possible areas in the ‘space,’ but rather piling on more respondents to test the same vignettes. The goal is to get a better measurement, a more precise measurement, but of course with the scarcely acknowledged possibility that the whole enterprise is looking into the ‘wrong’ area. This is the hypothetico-deductive method research [21].

Mind Genomics lies outside the standard realm of hypothetico-deductive research. One can think of Mind Genomics as a mapping exercise, a cartography, to discover information about how we think. One could use the method for hypothesis, but the research strategy is simply to create ideas about a topic, mix them, get reactions and determine how the ideas drive the reaction. There may be theory, or simply a mapping exercise. Like an explorer, one can study areas in which one is an expert or conversely areas in which one is completely ignorant. The data are accretive, as more and more of the topic area is explored by study after study. The end result is a database of the mind, created in what ends up being an efficient inexpensive, possibly results-directed manner or possibly random exploration, all at a lower price.  In other words, the world view of Mind Genomics is to increase knowledge, and create a small or a large database about a specific topic.  The topic may be virtually anything to which a person can respond after reading a description, as long as an underlying experimental design can create alternatives to the basic idea.

The third topic is simple. What did we find?  It’s about old age homes, ineffective plastic surgery, and financial ‘betrayal.’

Acknowledgment

The author acknowledges the original efforts to collect the data though It! Ventures LLC, and is especially grateful to the late Hollis Ashman for her efforts at putting together the study, and doing the preliminary analyses in 2003, when the data were first collected.

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fig 2

Measurement of Potassium Ion Diffusion through Dentine Using ISE

DOI: 10.31038/JDMR.2022523

Abstract

Objective: To measure the in vitro concentration of potassium ions (K+) on the opposite side of the dentine samples in real-time, using Potassium Ion Selective Electrodes (K+ ISE).

Method: An assembly array was designed and different sections (n=4) of dentine were acid etched in 6% citric acid and ultra-sonicated for five minutes. They were subsequently fixed into a polypropylene tube using impression dental material and immersed into simulated dentine fluid (SDF) which consisted of 0.01 mol/dm3 potassium chloride (KCL) solution. The K+ ISE was placed external to the polypropylene tube, to measure changes in the potassium ion concentration [K+] in the SDF for 60 hrs continuously. Application of potassium nitrate (KNO3) solutions of concentrations between 0.05-3 mol/dm3 were applied to the exposed dentine samples in separate experiments.

Results: Minimal changes in [K+] (<5 mmol/dm3) in the SDF (the opposite side of the sample) were measured by the K+ ISE when applying less than 600 mmol/dm3 of KNO3 solutions to the dentine sections. However, significant changes (P<0.05) in [K+] of 5-25 mmol/dm3 were measured in the SDF when applying a KNO3 solution of concentration more than 600 mmol/dm3 to the dentine samples, indicating greater penetration of K+ through the dentine matrix.

Conclusion: ISE may be used to measure ionic transfer in dentinal tubules although questions arise due to the sensitivity of the ISE and its suitability. However, it was demonstrated that increasing the concentration of an applied KNO3 solution to exposed dentine increased the [K+] in the SDF which was on the opposite side in the dentine disk model and premolar tooth with a cut cavity. This was also the case when the fluid flow was in the opposite direction to diffusion. This study demonstrates that ISE may be suitable for real-time diffusion experiments in dentine for possible future research into dental therapeutics which involve ion exchange.

Keywords

Potassium ion diffusion, Potassium ion concentration, Ion selective electrodes, Potassium nitrate, Dentine

Introduction

The use of Ion Selective Electrodes (ISE) in dental research has become prevalent to measure real-time ionic transfer processes. The method has been used to measure ion releases from restoratives and adhesives to prevent enamel demineralisation by measuring fluoride ion release [1] and the effect of calcium release from enamel in the presence of a solution containing zinc ions [2]. This method has not been used to measure the penetration of ions through the dentine matrix despite some possible limitations when using these electrodes [3]. Therefore, potassium ion concentration [K+] could theoretically be measured using ISE although there are no published in vitro studies where changes in [K+] on the opposite side of the dentine were measured using ISE methodology.

Measurement of ionic processes in dentine may be of interest as it is accepted that the prevailing hypothesis for nerve desensitisation by potassium ions (K+) is a direct diffusion mechanism. It has been demonstrated that K+ does not relieve dental pain by tubular occlusion to prevent dentine fluid flow [4-9] despite this theory remaining an enigma [10]. Potassium toothpaste and mouthwash formulations are effective at reducing dental pain associated with dentine hypersensitivity (DH) in humans [11-13]. A review by Orchardson and Gillam was undertaken to evaluate their efficacy and demonstrated numerous studies in which pain was reduced after the application of potassium-containing desensitisers [14]. Although the concentration of K+ may initiate depolarisation of the nerve fibres, the nerve fibres are unable to repolarise due to an imbalance of sodium and potassium ions [7,8,15]. However, this hypothesis has been criticised by some investigators as these experiments were ‘dissimilar’ to the clinical reality [16], and other investigators have also hypothesised that K+ may directly diffuse to desensitise the intra-dental nerves [17,18].

Stead et al. provided a mathematical framework of potassium diffusion in the clinical environment based on known parameters of the various constituents of the dentine tubule (DT) complex [19]. Furthermore, Stead et al., reported that a one-minute application of 500 mmol/dm3 of K+ increased the concentration of K+ at the inner end of the tubules for 20-30 minutes. However, this does not appear to be the case in the clinical environment, where users of potassium toothpaste would not usually brush each tooth for a minute [19]. According to this model, potassium-containing desensitisers may be able to exert a transient effect and this was demonstrated by Matthews and co-workers in the cut cavity model in humans [11,13].

Despite all these studies, the mechanism of K+ appears to work by a direct diffusion mechanism (simple concentration gradients). Numerous animal studies have also been conducted confirming the effect of K+ on intra-dental nerve activity [6, 20-23]. However, only a few in vitro K+ diffusion experiments have been conducted, purporting to minimal diffusion of K+ through the dentine matrix [24]. The present study was conducted to determine if sufficient diffusion K+ can occur through the DT in vitro and influence [K+] on the opposite side of the sample. This study was conducted to measure dentine permeability to K+ in real-time and whether ISE was suitable for such measurements; if suitable, then further studies can be conducted when K+ is combined with other anions as are the case in potassium-containing dental products.

Material and Methods

The present study was similar though not identical to previous historical experiments [11, 13, 24]. The objective was to assess whether ISE was suitable for measuring ion penetration in the dentine matrix, in this case, K+ as there was abundant in vivo literature on the effect of K+ ions on intradental nerve activity.

Experimental Design and Setup

The setup is displayed in Figure 1 and a flow diagram of the method is in Figure 2. The setup in Figure 1 was sufficient to undertake in vitro experiments to determine if ISE could measure the penetration of K+ through dentine in real-time. Experiments were also conducted where the flow was in the reverse direction (away from the pulp) and K+ diffusion was towards the pulpal side. The setup in Figure 1 was constructed from an acrylic stage and polypropylene tubing with the K+ ISE. In each case, the dentine model under investigation was fixed into the polypropylene tube using a polyvinyl siloxane impression material (Type 3 Part no. 28418, Extrude Kerr Corporation, USA). It was important to expose the dentine sections on both sides to allow the passage of K+ from the polypropylene tube, through the dentine sample and into the beaker containing simulated dentine fluid (SDF) [25]. The polypropylene tube was then immersed into the beaker containing 40 ml of SDF which in turn was immersed in a water bath (MX07H135-A12E, Polyscience, Illinois, USA) at 25°C to maintain a constant temperature during the experiments. The potassium nitrate (KNO3) solution was placed in the polypropylene tube on top of the dentine sample, 16 cm above the sample, to mimic flow and diffusion in the same direction and this flow was due to gravity. In separate experiments, a volume whose height was 1 cm above the sample was used to mimic flow from the SDF solution into the polypropylene tube and diffusion of K+ in the opposite direction (for practical reasons, it was not possible to increase the height differential more than 1 cm in this direction and only 1 ml in volume was used instead). The assembly was based on the designs of Uddin’s et al. [26] electrochemical cell, as this was sufficient to undertake permeability experiments with a K+ ISE. The beaker containing the SDF was covered with a 3D printed lid (Wanhao Duplicator i3 Plus V2, Dorchester, Dorset, UK) to prevent evaporation of the SDF solution. Also, the K+ ISE (ELIT8031, Nico 2000, Harrow, London, United Kingdom) was placed in the beaker containing the SDF only as it was necessary to measure the changes of [K+] in the external SDF solution which always had an initial concentration of 0.01 mol/dm3 potassium chloride (KCl) solution.

fig 1

Figure 1: Schematic of the experimental setup in measuring the change in the [K+] in the SDF with K+ ISE in the four dentine models immersed into 40 ml SDF

fig 2

Figure 2: Flow diagram of the Methodology used in the study

Solution Preparation

Experiments were conducted by changing the concentration of the KNO3 solution placed in the polypropylene tube. All chemicals used were obtained from Sigma Aldrich (St Louise, Missouri, US) with at least 99.9% purity. The chemicals used in this investigation were KNO3 salt (CAS number 7757-79-1, Product code: 221295) and KCl salt (CAS number 7447-40-7, Product code: P9333). The concentrations of the KNO3 solution placed in the polypropylene tube for each separate experiment on each of the dentine samples were 0.05, 0.1, 0.2, 0.3, 0.6, 0.8, 1, 1.5, 2, 3 mol/dm3. The concentration of KCl in the SDF was 0.01 mol/dm3, which was a calculated median value of actual values in the published literature. 2.5 mol/dm3 of NaCl was added to the SDF solution as a buffer in the preliminary experiments. It was determined that this was not always necessary due to the electrodes used in this study where K+ ISE had a lithium acetate reference electrode which had an “equi-transferrent filling solution”, i.e., both ions have the same, or nearly the same, mobility – e.g. lithium acetate, or potassium nitrate). These experiments with the ISE were calibrated and conducted following the technical specifications associated with the ISE.

ISE Preparation and Calibration

The K+ ISE was accompanied by a universal reference electrode; a lithium acetate double junction reference electrode (ELIT003n Nico 2000, Harrow, London, United Kingdom). These electrodes were connected to a dual-electrode head (ELIT 201, Nico2000, Harrow, London, United Kingdom). The diameters of these electrodes were 8 mm and had a length of 130 mm and the head was connected to a 4-channel ion analyser (ELIT4, Nico 2000, Harrow, London, United Kingdom) which recorded the voltage between the K+ ISE and the reference electrode in a specific concentration of the potassium-containing solution (KCl). The electrodes were calibrated by making specific concentrations of the KCl solutions and recording the voltage from a data logger (ELIT 4). The calibration of the K+ ISE was conducted from highly concentrated solutions to low concentrated solutions. This was completed by pouring specific volumes of 10, 20, 40, 60, 80 and 100 mmol/dm3 of the KCl solutions in separate beakers and placing the K+ ISE with its Li reference electrode in each of the beakers to obtain a voltage (mV) reading from each beaker. Log concentration against voltage was plotted and the gradient, according to the K+ ISE technical specification, should have been 54±5 mV. The calibration of the ISE was performed before the commencement of the 60 hr experiments for each of the four dentine samples and at each of the concentrations of the KNO3 solutions applied in the polypropylene tube on the exposed areas of the dentine. After each experiment, the electrodes were rechecked against the standard to ensure that the electrodes were in good calibration, which in all cases was within 54±5 mV. The reference electrode and K+ ISE were preconditioned and stored according to the instructions on the ISE technical specification. According to the technical specifications, the lowest concentration change that could have been detected by the K+ ISE was 0.01 mmol/dm3 and the maximum was 100 mmol/dm3. All experiments that were conducted could therefore only measure changes in K+ concentration between 0.01-100 mol/dm3. The calibration of the ISE also occurred in samples of the concentration mentioned above (see Figure 3). Also, to prevent pH changes, a buffer solution was used which involved adding 2 ml of 2.5 mol/dm3 NaCl in the plastic tube and the SDF per 100 ml of solution. In the preliminary experiments, the highest ionic strength of the measuring solution after 60 hrs of KNO3 in the SDF was at times more than 0.01 mol/dm3. However, it was not always very large and the necessity of the NaCl buffer was questionable although was used in all main experiments.

fig 3

Figure 3: Calibration of the K+ ISE with the gradient 52.117 mV/decade between 0.01 and 0.1 mol/dm3 [K+]

Simulating Flow

Experiments were conducted to simulate fluid flow by changing the volume of the KNO3 solution in the polypropylene tube above the dentine sample [11, 13, 27]. To simulate SDF flow into the polypropylene tube from the beaker, the height Δh (Figure 1) was changed so that it was negative with reference to the volume and height reached by the SDF in the beaker. The volume of the KNO3 solution in the plastic polypropylene tube was 1 ml in this case. The SDF should flow from the beaker into the plastic polypropylene tube whereas the [K+] in the polypropylene tube was greater than that in the SDF. This will simulate the inward diffusion of K+ and the outward fluid flow from the sample. To simulate flow and diffusion direction from the polypropylene tube and through the sample into the SDF, the application of the KNO3 solution at a higher pressure was necessary. The height of the KNO3 solution in the plastic polypropylene tube above the SDF levels Δh was 16 cm, which in this case would have led to flow due to gravity, as was similar to previous experiments conducted [28] although the SDF was not pressurized to simulate pulpal pressure. This effect was undertaken to deliberately ensure that a positive concentration change was measured in the SDF and then compare this to when the flow was reversed i.e., from the SDF through the dentine sample, into the polypropylene tube whilst diffusion occurred from the polypropylene tube, through the dentine sample and then into the SDF. It must be noted this was done simply to measure penetration of K+ through the dentine sample and it was not modelling pulpal pressure. The volume of SDF (containing 0.01 mol/dm3 KCl) in the beaker was 40 ml for the experiments with each of the four dentine sections.

Dentine Sample Preparation

Ethics approval was obtained (Ethical code: QMRECC200014/17) to enable the investigators to acquire human teeth from the Royal London Dental Hospital Tooth Bank. The dentine samples used were 1) dentine disks; 2) a mandibular premolar tooth with a crown section and a cut cavity; 3) a root section from the same mandibular premolar tooth and 4) a crown section of a molar tooth with a cut cavity. 0.5 mm thick mid-coronal dentine disks were sectioned from human mandibular premolar teeth using a diamond saw (Struers Accutom-5, Willich, Germany) and initially acid etched in 6% citric acid for two minutes to remove the smear layer. A mandibular premolar tooth was sectioned into two pieces: the crown section and the root section; a 2 mm diameter cavity was made from the occlusal surface of the crown section using a dental bur until the dentine was exposed from the mid coronal section; the roots were sectioned using a diamond saw (Struers Accutom-5, Willich, Germany) so that the tubules were exposed on the mid coronal sides. The whole crown section was acid etched in 6% citric acid for two minutes. The cementum from the roots section used in experimentation was removed by polishing with a polishing paper (P-1000) and both were acid etched in 6% citric acid for two minutes. The apex of the root was sealed with a polyvinyl siloxane impression dental material (Type 3 Part no. 28418, Extrude Kerr Corporation, USA). The root of a maxillary molar tooth was removed and sectioned along the cervical region and a crown section was treated in the same way that the crown section of the premolar tooth was and having the same diameter of the cavity. All samples were ultra-sonicated in deionised water for five minutes after acid etching and stored in 60% ethanol and immersed in deionised water for 24 hours before experimentation. All samples were also thoroughly rinsed in deionised water before the start of each experiment. After each experiment, the samples were thoroughly washed with deionised water and stored in 60% Ethanol and then immersed again in deionised water for 24 hours before the next set of experiments. Experiments were also conducted on the application of low to high concentrations of the KNO3 solutions.

Statistical Test Method

88 experiments were conducted and all experiments were categorised into two groups; Group 1 (experiments conducted for applications of the KNO3 solution to the four samples being <0.6 mol/dm3) and Group 2 (≥0.6 mol/dm3). This grouping was undertaken as it was reported in the literature; that 0.5 mol/dm3 of KNO3 relieved sensitivity (DH) and most dental products containing K+ have these concentrations [14]. Therefore, it was hypothesised that the ISE should be able to measure the difference between these two groups and that the larger the concentration of KNO3 applied, the larger the change in concentration in the SDF. The statistical test to determine the statistical difference between Group 1 and 2 used was a two-tailed Student T-test assuming unequal variance. 32 experiments were conducted with the dentine disk, 32 experiments were conducted with the crown section of a premolar tooth, 12 experiments were conducted with the premolar root section and 12 experiments were conducted with the molar crown section with a cut cavity. Table 1 displays the breakdown of each of these experiments conducted.

Table 1: Breakdown of experimentation conducted with each of the four dentine samples.

table 1

Results

Before the commencement of each experiment, the K+ ISE was calibrated. When plotting Log10 concentration as a function of voltage, the gradient was always 50-54 mV/decade, in agreement with the technical specifications of the K+ ISE. Otherwise, the K+ ISE was recalibrated or replaced with a new K+ ISE; the K + ISE was replaced after 5 failed attempts of recalibration, which only occurred once in all experiments conducted. Figure 3 demonstrates an example of the calibration of the ISE where it can be observed that the gradient was 52.117 mV/decade. Also, Figure 4 displays the real-time measurement of the potassium ion concentration in the SDF after diffusion has occurred for two different concentrations of KNO3 applied to the dentine disk model over 60 hrs.

fig 4

Figure 4: Preliminary experiments: real-time measurement of [K+] in SDF when applying 0.6 mol/dm3 and 0.1 mol/dm3 in separate experiments to the dentine disk model at 16 cmH2O

In Figure 4, it can be observed that there was a large increase in the [K+] in the SDF (initially containing [K+] ≈ 0.01 mol/dm3) when applying the KNO3 solution of 0.6 mol/dm3 (compared to 0.1 mol/dm3) at 16 cmH2O to the dentine disk. The pressure, at which the KNO3 solution was applied, also appeared not to affect the change in [K+] in the SDF.

For all experiments conducted, statistically significant changes (P<<0.05), were measured in the [K+] in the SDF when concentrations of the KNO3 solution applied to any of the samples were more than 0.6 mol/dm3 (equivalent to 600 mmol/dm3). This was most statistically significant for the dentine disk model where the mean [K+] in the SDF for Groups 1 and 2 were 0.106 mmol/dm3 and 13.615 mmol/dm3 respectively after 60 hrs. In the premolar crown tooth, the mean for Group 1 and 2 were -0.415 mmol/dm3 and 4.063 mmol/dm3 respectively after 60 hrs and there was a significant difference between the two groups (P=0.0002). In the premolar root section, the mean measurement for Group 1 concentration in the SDF and Group 2 concentration in the SDF were -2.351 mmol/dm3 and 8.149 mmol/dm3 respectively, with a significant difference between the two groups (P=0.041). However, when applying the KNO3 solutions of concentrations more than 0.6 mol/dm3 to the molar crown section, there were no statistically significant differences observed between Groups 1 and 2 (P=0.1). In addition, the [K+] in the SDF was not significantly different (P=0.96) when the KNO3 solution was applied to the four samples at 16 cmH2O or atmospheric pressure.

Figures 5a and 5b show that there was significant diffusion of K+ through the dentine disk and the premolar crown sections of dentine when applying larger (more than 0.6 mol/dm3) concentrations of the KNO3 solution. This resulted in an increase in the [K+] in the SDF between 4 and 20 mmol/dm3 for the dentine disk and between 3 and 10 mmol/dm3 for the premolar crown section. However, it must be acknowledged that at times there was no increase in [K+] in the SDF, for example, when applying 2 mol/dm3 of KNO3 at 16 cmH2O to the premolar crown section which only increased the [K+] in the SDF by 0.6 mmol/dm3 (Figure 5b). This was also the situation when applying the 3 mol/dm3 KNO3 solutions to the premolar root dentine in Figure 5c (which produced a change in [K+] in the SDF of 1-1.5 mmol/dm3) and applying 0.6 mol/dm3 and 3 mol/dm3 KNO3 solutions to the crown section of molar tooth (Figure 5d). However, the application of concentrations of the KNO3 solution less than 0.6 mol/dm3 did not produce any significant changes in the [K+] in the SDF for all four samples. Occasionally there was a decrease in the [K+] in the SDF which was unexpected and could only be attributed to electrode drift. In the dentine disk, there was generally an increase in [K+] in the SDF of about 0-2.5 mmol/dm3. In the premolar crown section of the tooth, this increase was only between 0-0.8 mmol/dm3. However, it can be observed from Figures 5c and 5d for the premolar root dentine and a molar with a cut cavity that there was a reduction in the [K+] in the SDF at applications of KNO3 less than 0.6 mol/dm3. The results in the Dentine disk model and the Premolar with a cut cavity could not be reproduced in the molar tooth with a cut cavity or in the root section.

fig 5a

Figure 5a: Measurement of the final [K+] in the SDF after 60 hrs for each application of KNO3 solution to Dentine Disk

fig 5b

Figure 5b: Measurement of the final [K+] in the SDF after 60 hrs for each application of KNO3 solution to the crown section of a premolar tooth with a cut cavity

fig 5c

Figure 5c: Measurement of the final [K+] in the SDF after 60 hrs for each application of KNO3 solution to the premolar root dentine section

fig 5d

Figure 5d: Measurement of the final [K+] in the SDF after 60 hrs for each application of KNO3 solution to the crown section of a molar tooth with a cut cavity

Discussion

This study aimed to determine whether K+ ISE was suitable for the detection of potassium ion concentration [K+] changes on the opposite side of the dentine samples in real-time. Experiments were conducted to deliberately measure a positive change in [K+] in which both flow and diffusion were in the same direction. The flow was then reversed in the opposite direction to K+ diffusion in separate experiments. Changes in the [K+] in the SDF were measured electrochemically using a K+ ISE. It can be observed in Figure 5a-d that the pressure at which the KNO3 solution was applied to the dentine does not affect the changes in [K+] in the SDF. The diffusion of K+ also does not appear to be affected by the flow rates. This may be consistent with the in vivo observations of Ajcharanukul et al., [11] and Noparatkailas et al., [13] despite the modelling of the oral environment not being the main objective in this study. If the oral environment were modelled, the SDF would have to be enclosed in a chamber at 20 cmH2O above atmospheric pressure [24]. The experiments conducted simply demonstrate that a concentration gradient leads to the penetration of K+ through the dentine matrix as measured by the ISE method in real-time instead of taking a measurement every 60 seconds for 20 minutes [24]. However, application of a KNO3 solution of less than 0.6 mol/dm3 applied to the dentine disk and premolar with a cut cavity appeared to on average produce insignificant diffusion of K+, producing less than 10 mmol/dm3 increase in the [K+] of the SDF. It appears that when applying 0.6 mol/dm3 or more of a KNO3 solution to the dentine disk and a crown section of a premolar tooth for 60 hrs, this produced significant K+ diffusion in the SDF and concentrations changes were more than 10 mmol/dm3. However, this was not observed with the root dentine model, or in the crown section of a maxillary molar tooth and the present study could not reproduce this in these models possibly because of the biological variation, the possible preparation method or even the small sample sizes used in the study. In fact, the results of the premolar tooth and the dentine disk were not reproducible in the crown section molar tooth and the root dentine may also be due to the variation in the orientation within the DT in the samples used in the experiments.

When the flow was from the SDF to the solution in the polypropylene tube with the dentine disk model and the premolar crown section tooth model, there was no question of diffusion occurring. However, in the case of flow from the polypropylene tube to the SDF and diffusion in the same direction, it is questionable whether this is a diffusion mechanism or just simply a flow due to gravity and there appears to be no evidence as to which was the dominant mechanism. However, K+ ISE was still able to measure changes in the [K+] of the SDF. Occasionally there was a decrease in [K+] in the SDF which could have been attributed to the drift in the electrodes, although this was minimal (<3 mV/day) and there was no evidence suggesting that this was due to the electrodes used in the experiments. Applications of the KNO3 solutions of concentrations 0.6 mol/dm3 and higher increased the [K+] in the SDF, although this was not observed in the molar tooth with a cut cavity and to some extent in the root dentine as previously mentioned. Therefore, another explanation is that there was a local concentration build-up of KNO3 in the crown sections and the root sections of the dentine tubules although there was no evidence of this.

It can also be stated that these experiments support the DT that 5-6 mol/dm3 of KNO3, as would be present in most potassium-containing dental products, appears to produce significant diffusion of K+ compared to concentrations less than 5-6 mol/dm3. Potassium-containing desensitisers relieve pain associated with DH [14], and the present study demonstrates the significance of having 5 mol/dm3 or more of [K+] in dental products. However, it must be noted that the experimental setup does not represent the oral environment as it was difficult to model the oral environment with the current setup, although it may be possible with an entirely different setup where the SDF was in a pressurised chamber to mimic the pulpal pressure. It must also be acknowledged that the ISE did not measure the [K+] in the nerves per se as the present study was an in vitro study, which according to Fick’s law is where there would have been a higher concentration of K+ within the nerve membrane and the surrounding area rather than in the dentinal fluid within the DT. However, this is an assumption and may therefore be impossible to measure. Furthermore, there are challenges in conducting these types of experimentation with a K+ ISE since the KNO3 solution was applied on top of the sample. In future experimentation, with an inductively coupled plasma mass spectrometry (ICP analysis) could be used as this would allow for very low concentrations of K+ to be detected after K+ had diffused into the sample through the DT into a much smaller volume of SDF. It was not clear whether the final experimental results in this study appear to be contrary to the in vitro diffusion experiments of Miller et al., who measured the penetration of K+ in combination with other ingredients through acid-etched dentine disks in a 2-chamber diffusion cell and concluded that there was ‘very’ limited diffusion of potassium in both etched and untreated dentine disks [14, 24] but this can be explained by the different parameters used and the enclosure of a second chamber that mimicked pulpal pressure. The setup used by Miller et al., may present challenges to the real-time monitoring of K+ diffusion using ISE. However, Miller et al., was taking samples every 60 seconds for 20 minutes and then measured the [K+]. The use of ISE was beneficial in that the readings were taken automatically, and the concentration could be measured over longer periods. However, it can be observed from Figure 4 that the penetration of K+ through the dentine disk model is minimal which agreed with Miller et al., [24]. Further research with K+ ISE is recommended, such as measuring [K+] in the saliva following brushing the teeth with potassium desensitisers in vivo and measuring whether diffusion is affected by different anions such as citrates, tartrates, and oxalates, which could also have an occluding action. Potassium Ion Selective Electrodes (K+ ISE) were able to measure the changes in the potassium ion concentration ([K+]) in the SDF which was an indicator of the [K+] in the dentine tubules (DT). Other anions in combination with other ingredients (as possible mixtures) may also affect the penetration of K+ (and possibly other ions), such was the case when Miller et al. [24] treated dentine disks multiple times with sensitive tartar control. In this situation, experiments with K+ ISE may be useful also to test whether nitric oxide may act as a secondary messenger which could be measured using the ISE method. Further research however should be conducted to evaluate the influence of any confounding factors in a suitable model mimicking the oral environment.

Conclusion

  • ISE real-time measurements may be suitable for permeability measurements of the dentine matrix to different ions.
  • K+ ISE was able to demonstrate that 5 mol/dm3 KNO3 applied to dentine significantly affected the concentration of K+ on the opposite side of the sample except for in the premolar root section and crown section of a molar tooth.
  • KNO3 solution of concentration less than 5 mol/dm3 appeared to produce insignificant diffusion in all dentine models.
  • K+ ISE demonstrated the significance of having 5 mol/dm3 or more in dental products containing K+.
  • The pressure of KNO3 (volume of KNO3 and the height reached above the sample) applied to the models of dentine does not appear to affect the diffusion result i.e., its ability to affect the concentration on the opposite side of the sample.
  • Both the Dentine disk and premolar tooth models appeared to be much more reliable models when undertaking these experiments. However, further research will be needed if root sections and crown sections with a cut cavity are used.
  • Further research is required to mimic the oral environment and change other relevant parameters.

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FIG 2

Mind-Set Based Signage: Applying Mind Genomics to the Shopping Experience

DOI: 10.31038/ASMHS.2022653

Abstract

The paper presents a new approach to optimizing the shopper experience, combining easy-to-implement tools for understanding shopper mind-sets at the granular, specific level (Mind Genomics; www.BimiLeap.com) with a simple, rapid way which assigns any shopper or prospective shopper to the relevant mind-set for that granular topic (www.PVI360.com). The approach begins with a simple study of the motivating power of relevant messages and thus uncovers mind-sets or groups of respondents showing similar patterns of what motivates them. Then, using the same data, the approach creates a simple questionnaire comprising six questions taken from the original study, the pattern of answers to which assigns a new person to a mind-set. Once the mind-set of the shopper is ‘identified’ for the granular topic using the PVI (personal viewpoint identifier) it is a matter of giving the shopper the appropriate motivating message, either at the time of shopping in brick and mortar store or e-store, or sending the message on the Internet in the form of an advertisement or individualized coupon.

Introduction

The past two decades have seen an explosion of knowledge about the consumer, the knowledge emerging from the speed and affordability of internet-based surveys, the sophisticated analysis of masses of cross-sectional data known as Big Data, and the application of artificial intelligence to uncover patterns. What continues to emerge is that nature is simultaneously tractable and intractable. As the macro level we know what to expect in terms of purchase patterns and expected time to repurchase, some of which knowledge may transfer to the level of the individuals, only for the general pattern just exposed to be disrupted by the idiosyncrasies of each individual.

The world at the time of this writing (Fall, 2022) is quite different from the world of just a decade ago, and most certain far different from the earlier decades. The notion that one could change advertisements is well-accepted, easily and widely done. Outdoor advertisements and LED technology assault us everywhere we go. We are accustomed to see large billboards with attention-grabbing sequences advertisements, the modern day evolution of signage of decades ago, once static, now plastic, and changeable at will. Now technology makes it possible to individualize the messaging for an individual, much as is done on a cell phone. This paper presents one approach.

The organizing nature of this paper is how one might advertise to a single customer, using science to uncover the ‘mind’ of that customer ahead of time. The objective of this study was to understand the different types of messages which might appeal to shoppers of cereal in the middle isle, and shoppers of yogurt in the refrigerated dairy section. Could the technology of 2022 be set up to deliver the proper messages to an individual who is walking along the store? And could the approach be set up to be done at scale, affordably, quickly, with scientific precision rather than with guessing about what the person wants based upon who the person is. This latter condition is important. It means that the messages must be delivered to the person most likely to respond to the specific messages.

The studies reported here were done with the intention of testing out the possibility that one could create a knowledge-based system about messaging for simple, conventional, familiar products. The paper does not deal with new to the world products which have their own mystique, and both positive and negative messaging attached. Rather, the paper deals with what one might call ‘tired, old, utterly familiar’ products that may not be susceptible to the romance of the new and different.

A Short Historical Overview to ‘Messaging the Shopper’

The notion that one can influence the shopper by proper messaging is decades old, and the subject of numerous experiments. Indeed, the real-world behaviors of shoppers and the change in behavior resulting from the proper messaging opens up the topic to anyone interested in messaging, whether the interest be theory such as experimental psychology, to applied science such as consumer psychology, and of course the world of business applications. As a consequence, there have been a number of different studies focusing specifically on shopping.

  1. Schumann et al. [1] reported only modest effectiveness of signage in shopping cart. To summarize their results: “Findings from both studies reflect that over 60% of the 2 samples noted the presence of the signs in their carts. When Ss were questioned about their awareness of cart advertising on a specific occasion, only 3.0–6.5% recalled the product. There was no evidence that cart signage acts in a subliminal fashion that results in the purchase of the brand.” It may well be the signage in the cart was general information about the product, not necessarily information that would tug at the heartstrings of the shopper.
  2. Dennis et al. [2] confirmed the efficacy of digital signage but argued for emotional content. They noted that the typical content of digital signal is ‘information-based’ whereas digital signage might be more effective if it were to comprise emotional messaging as well, or even instead of simple information. Results are limited as the DS (digital signage) screens content was information based, whereas according to LCM, (Limited Capacity Model of Mediate Messaging) people pay more attention to emotion-eliciting communications. The results have practical implications as DS appeals to active shoppers.
  3. Buttner [3] proposed at two types of shopping orientations (mind-sets), task focused and experiential shopping, respectively. They report that “Activating a mindset that matches the shopping orientation increases the monetary value that consumers assign to a product. …. marketers and retailers will benefit from addressing experiential and task-focused shoppers via the mindsets that underlie their shopping orientation.
  4. Chang et al. [4] reported that mind-sets are important, and that the communication should consider the different mind-sets. Their notion was that people may or may not be skeptical to advertising. Those who have a ‘utilitarian orientation’ and an ‘individualistic’ mind-set tend to be skeptical about advertising, and need messages which are different from those individuals who have a ‘hedonic’ and a ‘collectivistic’ mind-set. Chang and Chen bring this topic into discussions about CRM and donating, but their notions can be easily extended to the right type of messaging for digital signage.

The Contribution of Mind Genomics to the Solution

Mind Genomics is an emerging science which grew out of the need to understand how people make decisions about the issues of the ‘everyday’. Mind Genomics rests on the realization that the ‘everyday’ situations are compounds of different stimuli. To study these stimuli requires that the respondent, the test subject, be confronted by compound test stimuli which comprise different aspects of everyday situation, stimuli that the respondent ‘evaluates’, such as rating the combination. Through statistics, applied after the researcher properly sets up the blends, it becomes possible to understand just exactly what features ‘drive’ the rating. Properly executed, this seeming ‘roundabout way’, testing mixtures, ends up dramatically revealing the underlying mind of the respondent [5,6].

The foregoing process, testing systematically created mixtures and deconstructing through statistics, stands in striking opposition to the now-hallowed approach of ‘isolate and study.’ The traditional approach requires that the features of the everyday be identified, and separately evaluated, one feature at a time. Typically the evaluation ends up presenting each of the features separately, getting a rating, analyzing the pattern of ratings across people, and then identifying the key variables which a difference.

Attractive as the traditional methods may be, the one-at-a-time is severely flawed for several reasons:

  1. Combinations of features are more natural. It may be that a feature will receive a different score when evaluated alone compared to the evaluation of the feature as part of a mixture. And it may be that the feature will receive different scores when evaluated against backgrounds provided by a variety of other features. Thus, the wrong answer may emerge.
  2. People may change their criterion of judgment when presented with an array of different types of features, such as features dealing with product safety versus features dealing with branding, with benefits, and so forth. All too often the researcher AND the respondent fail to recognize the underlying shifts in these criteria.
  3. It becomes very difficult to ‘game the system’ when the test stimulus comprise a combination. Often, and perhaps even without knowing it, the respondent tries to assign the ‘correct’ or ‘socially appropriate’ answer. Such effort to ‘be right’ is doomed to failure when the respondent is presented with a combination. Often the respondent asks the researcher or interviewer for ‘help’, such as asking ‘what do I pay attention to in this combination?’

Mind Genomics works with the response to combination of text messages, called vignettes. The vignettes comprise specified combinations of elements, viz., verbal messages. Table 1 below (left part of table) shows these messages. The messages are sparse, to the point, paint a word picture. The vignettes are created according to an underlying plan called an experimental design. The experimental design may be thought of as a set of different combinations, different recipes, combining the same messages, the same elements, in different ways.

Table 1: Positive elements for cereal, viz., and those elements which drive the rating of a vignette towards definitely buy/probably buy). All elements shown have positive coefficients of +2 or higher.

TABLE 1

A key difference between Mind Genomics and conventional research is how Mind Genomics considers variability among people and how it deals with that variability. We start the comparison by considering conventional research, which often considers variability in the data to be error, usually unwanted error which masks the ‘signal’. Occasionally the variability can be traced to some clear factor, such as the nature of the respondent, in which case this irritating variation hiding the signal is actually a signal itself. For the most part, however, researchers consider variability to be unwanted, and either suppress it by meticulous control of the test stimulus/situation, or average out the variability by working with a lot of respondents, and assuming that the variability is random, and so will cancel out.

In the world of Mind Genomics variability is considered in a different light. Certainly there is the appreciation of error, but there is also the acceptance of the fact that people differ from each, and that these differences may be important. The differences between people are not necessarily random error, but rather point to potential profound differences among people, albeit differences which exist in a small, granular aspect of daily life. In other words, sometimes the differences are important, and sometimes the differences are merely random noise.

Explicating the Research Process

For the project reported here, the researcher selected two products (cereal, yogurt), asked six questions about the product, questions that could be used to create consumer-relevant messages, and then developed the database of 36 possible consumer messages for each product.

Thus far, the process is quite simple; requiring only that the researcher do a bit of thinking about what types of messages might be relevant to consumers. One of the in-going ‘constraints’ from the perspective of marketing and the trade was that the messages had to be of the type which drive purchase. It was not an issue of building one’s brand through advertising. Rather, the messages were chosen so that they could be put on a coupon, or flashed on an LCD panel as the respondent ‘walked by.’

The actual process of developing the raw materials can be daunting for those who are not professionals. In the two studies reported here, a significant effort was expended to develop the six ideas which tell a ‘product story’. One the six ideas are developed, the most intellectually intense part of the effort, the creation of six messages for each idea becomes much easier. Recently, the creation of these basic ideas (or questions), and the elements (or answers) has been improved by a process called Idea Coach, which provides different options, using artificial intelligence (www.BimiLeap.com). The data reported here were collected before the Idea Coach system was incorporated into Mind Genomics:

  1. The actual selection of messages generated six groups of six message, one set of 36 such messages for cereal (Table 1), and another set of comprising different messages, for yogurt (Table 2).When looking at the table, the reader should keep in mind that the elements either pain a simple word picture, or specify a specific a specific claim that could be turned into ‘copy.’
  2. When creating the messages and assigning them to groups, the only requirement for the researcher is to ensure that all of the messages in a single idea (viz., all the answers given to a single question) remain together. For example, messages about ‘calories’ must all be put into one group or idea, and not split across two groups or questions. The rationale for this requirement comes from the fact that the underlying experimental design will need to combine elements from different questions (described below). When the researcher puts a calorie message in one group, and another calorie messages in a second group, there is the likelihood that the underlying experimental design may put these mutually incompatible messages into the same combination.
  3. Once the elements are created, comprising the question and the six answers, as shown in Tables 1 and 2, the next step is to use the basic experimental design, which specifies 48 combinations, each combination comprising either three or four elements. Each combination or vignette contains at most one element from any question. The vignettes are by design incomplete, since there are six questions, but a vignette can only have three or four answers, one from three or four questions. As noted above, each respondent evaluates a unique set of 48 combinations. The underlying mathematics remains the same. What changes is the assignment of a message to a code. For example, for one person, element A1 may be assigned as A1, whereas for another person a permutation is done, so the former A1 becomes A2, A2 becomes A3, et. the experimental design is maintained, but the combinations change [7].
  4. The final steps comprise the introductory message and the rating scale. In Mind Genomics studies most of the judgment must be driven by the individual elements, and not by the introductory statement. It is better to be vague about the product, and let the individual elements drive the reaction, rather than to specify too much in the general introduction. For this study, the introduction was simply ‘Please read this description of cereal and rate it on the 5-point scale below. For yogurt the introductory statement was virtually the same ‘please read this description of yogurt and rate it on the 5-point scale below’
  5. The five-point rating of purchase is anchored: 1=definitely not buy, 2 = probably not buy, might not/might buy, 4= probably buy, 5 = definitely buy. The anchored five point purchase intent scale has been used for many decades in the world of consumer research, both because the scale is sensitive to differences and because managers understand the scale, and generally look at the percentage of responses that are 4 and 5 on the 5-point scale. These two rating scale points are probably buy and definitely buy. The scale is often transformed to a binary scale, as was done here. Ratings of 4 and 5 were transformed to 100. Ratings of 1, 2 and 3 were transformed to 0. Managers who use the data more easily understand a yes/no scale, buy/not buy.
  6. Following the evaluation of 48 vignettes, the respondent completed a short self-profiling questionnaire, providing information about gender and age.
  7. Respondents were sent one of two links, the first appropriate to the cereal study, the second appropriate to yogurt. Approximately 70% of the individuals who were invited ended up participating. The high completion rate can be traced to the professionalism of the on-line research ‘supplier’. As a general point of view, it is almost always better to work with companies specializing in on-line research. Trying to recruit the respondents oneself ends up with a completion rate much low, often lower than 15%.

Table 2: Strong performing elements for cereal, for divisions of respondents into two complementary mind-sets, and then into four complementary mind-sets. All elements shown have positive coefficients of +10 or higher.

TABLE 2

Creating the Database and Analyzing the Data for a Study

Each respondent ended up evaluating 48 different combinations, called vignettes, assigning each vignette a rating on an anchored 5-point scale. The next step creates a ‘model’ or equation showing how each of the 36 elements about the product ‘drives’ purchase intent. Recall that all 48 vignettes of a respondent differed from respondent to respondent, although the mathematical structure was the same. This ‘permutation’ strategy allows the research to cover a large percent of the possible combinations [7].

In order to uncover the impact of the elements, the key variables, it is necessary to create an equation relating the presence/absence of the 36 text elements about the product to the rating. This can be easily done. The data are easily analyzed, first by OLS (ordinary least-squares regression) and then by clustering. OLS regression shows how the 36 elements ‘drive’ the response (purchase). Clustering identifies groups of respondents with similar patterns of coefficients groups that we will call ‘mind-sets.’

  1. The OLS regression, applied to either the individual data, or to group data, is expressed by the following: Positive Intent to Purchase = k0 + k1(A1) + k2(A2) . k36 (F6).
  2. For regression analysis to work, the dependent variable, the transformed variable (either 0 or 100) must show some small variation across the different 48 ratings for each individual respondent. Often, respondents confine their ratings to one part of the scale (e.g. 1-2; 4-5, etc.). To avoid a ‘crash’ of the OLS regression program, and yet not affect the results in a material way, it is a good idea to add a vanishingly small random number (e.g. around 10-4) to every transformed rating. The random number ensures variation in what will be the dependent variable, but does not affect the magnitude of the coefficients which emerge from the OLS regression.
  3. The underlying experimental design for each individual respondent makes it straightforward to quickly estimate the equation, either for individuals or for groups. The coefficient, whether for individual or for group, shows the degree to the element drives the response the rating of ‘definitely or probably purchase.’ The individual coefficients, viz., for the hundreds of respondents, are typically ‘noisy’, but when the coefficients become stable and reproducible when the corresponding coefficients are averaged across dozens of respondents, or when the equation is estimated from the raw data of dozens of respondents.
  4. The additive constant (k0) shows the estimated proportion of responses that will be 4 or 5 (viz., definitely purchase or probably purchase), in the absence of elements. Of course the underlying experimental design dictated that all 48 vignettes evaluated by any respondent would comprise a maximum of four elements (at most one element from a group) and a minimum of three elements (again, at most one element from a group, not more).
  5. The 36 individual coefficients (A1-F6) represent the contribution of each element to the expected interest in purchasing. When an element is inserted into a vignette, we can estimate its likely contribution by adding together the additive constant and the coefficient for the element. The sum is the percent of the respondents who would assign a rating of 4 or 5 to that newly constructed vignette.
  6. One of the ingoing tenets of Mind Genomics is that there exist groups in the population which think about the same topic, but in different ways. The information to which these respondents react may be the same but these groups use the information in different ways. Some respondents may value the information so that the information appears to covary with their rating of purchase the product. In contrast, other respondents may completely ignore the information. These differences reflect what Mind Genomics calls ‘mind-sets’, viz groups of individuals with clearly defined and different ways of processing the same information.
  7. The mind-sets emerge through the well-accepted statistical analysis called clustering [8]. Briefly, the clustering algorithm computes the Pearson correlation between pairs of respondents, based upon their 36 pairs of corresponding coefficients. Respondents with similar patterns (high positive correlation) are assigned to the same mind-set. Respondents with dissimilar patterns (negative or low positive correlations) are assigned to different mind-sets.
  8. For this study the ideal number of mind-sets is as few as possible. The paper reports the results emerging from dividing the respondents into two mind-sets, and then into four mind-sets, to show the effect of making the clustering more granular. The focus will be on interpreting the results from the two mind-set solution, and creating a tool to assign a new person to the one of the two mind-sets.

Applying the Learning – Cereal

Our data with 328 respondents provides us a wealth of information about to say, what not to say, and to whom. Table 1 shows the results for cereal. The table is organized with the key subgroups of respondents across the top and the messages down the side. In order to make the table easier to read, and allow the patterns to emerge, the table only shows positive coefficients of 2 or higher. The other coefficients were estimated, but are not relevant to the presentation since they do not drive positive interest in purchase. Furthermore, Table 1 shows strong performing elements as shaded cells. Strong performing is defined as a coefficient of +10 or higher. Table 1 is rich in detail. The table shows the results from running the aforementioned linear equation using the data from all respondents (total), then the data by gender, then by age.

  1. The additive constants differ, neither by gender nor age. Again and again Mind Genomics studies reveal that for the most part, conventional methods dividing people fail to show dramatic differences in how these divisions generate groups which think differently. It is eternally tempting to divide people by who they are, and presume that because people are different they think differently.
  2. The total panel of 328 respondents shows very few positive elements, and no strong elements. That is, knowing nothing else we cannot find elements which strongly drive purchase intent. Most of the elements are blank, meaning that the coefficients for those elements are either around zero or negative. In effect, ‘doing the experiment,’ viz. evaluating different messages, fails to uncover strong performing elements. No matter what experts might think, there are no apparent ‘magic bullets’ for cereal.
  3. A first effort to divide groups looks at gender. The additive constant is the same, but the females have a few more positive than do the males. Yet, none of the elements are strong drivers purchase when evaluated in the body of a vignette.
  4. The second effort divides the respondents by age. In terms of the additive constant, the younger respondents (ages 18-39) show a slightly higher additive constant than do the older respondents (age 40+; constants of 58 vs 53). The only strong performer (coefficient >1= 10) is S4 for the younger respondents: The same great taste of cereal only better.
  5. The third effort divides the full set of respondents into exactly two mind-set and then into exactly four mind-sets using k-means clustering [8]. To save space and make it easier for patterns to emerge, Table 2 shows the only those elements which perform strongly in at least one mind-set of the six created (two mind-sets + four mind-sets = six mind-sets). ‘Performing strongly’ is again operationally defined as a coefficient of +10 or higher. The groups with fewer strong performing elements will be harder to reach.
  6. Focusing just on the two mind-set solution, Mind-Set 2 is more primed than Mind-Set to be interested in buying the cereal (additive constant of 68 for Mind-Set 2, additive constant of 38 for Mind-Set 1). However, Mind-Set 1 shows two elements which excite its members:

O2: A tasty breakfast choice makes it easy to maintain a healthy body weight

O4: Ideal choice for those concerned about eating too much sugar

Applying the Learning – Yogurt

Our second study, this time with 307 respondents, shows similar patterns. Table 3 shows the data for the total panel, gender, and age. Table 4 shows the strong performing elements for the mind-sets, viz., those with coefficients of +10 or higher.

  1. The total panel again does not show strong performing elements (coefficient >= +10).
  2. The additive constants differ dramatically by gender. Recall that the additive constant is the basic level of purchase intent estimated in the absence of elements. Males shows a higher basic intent, females show a lower basic interest (74 vs 54). This is a dramatic difference.
  3. Closer inspection of Table 3 reveals that the coefficients for the males are around 0 or lower whereas there are a number of coefficients for females which are moderately positive. Males have a basic higher acceptance, but do not show any strong performing elements. In contrast, females show the lower basic acceptance, but are more selective. The two elements which drive their purchase intent are:
  4. F4: So flavorful. it will satisfy your sweet taste

    F5: Made with natural flavoring

  5. The second effort divides the respondents by age. In terms of the additive constant, the younger respondents (ages 18-39) show a lower additive constant, the older respondents show a higher additive constant (50 vs. 62).
  6. The younger respondents find five elements to drive purchase:

    E6                    Great taste with none of the guilt 

    F4                    So flavorful, it will satisfy your sweet taste

    O3                    A refreshing healthy snack the whole family love

    C1                    Ready to eat when you are

    F6                    Flavor which sweetens

    In contrast, the older respondents find only one element to drive purchase

    F5                    Made with natural flavoring                    7

  7. The results emerging from clustering show the two mind-sets (MS1 of 2, MS2 of 2) to have dramatically different additive constants (39 for MS1 of 2; 72 for MS2 of 2). Mind-Set 2 is prepared to purchase, even without messaging, whereas Mind-Set 1 must be convinced. Fortunately, eight of the 36 elements for yogurt perform strongly, two performing quite strongly (F4, F5):

F5:            Made with natural flavoring

F4:            So flavorful. it will satisfy your sweet taste

C2:            Comes in snack size, great for packed lunches

B2:            Less sugar, less calories

C5:            A hassle free healthy snack – goes where you go

B4:            It’s good because IT’S REAL

C1:            Ready to eat when you are

F2:            Uses flavors to sweeten for a healthier you

Table 3: Positive elements for yogurt, viz., those elements which drive the rating of a vignette towards definitely buy/probably buy). All elements shown have positive coefficients of +2 or higher.

TABLE 3

Table 4: Strong performing elements for yogurt, for divisions of respondents into two complementary mind-sets, and then into four complementary mind-sets. All elements shown have positive coefficients of +10 or higher.

TABLE 4

Part 2– Messaging the Shopper

One thing we learn from Tables 1 and 3 versus Tables 2 and 4 is that when we look for a strong message for the total panel, we will not find any strong message for Total Panel, for either food. Tables 2 and 4 tell us that when we divide the shoppers in two mind-sets, the one mind-set for each food is ready to buy the food, whereas the other, complementary mind-set can be persuaded to buy, but only when the correct messages are ‘beamed’ to this second group of shoppers. It is to the task of finding this group of shoppers and then sending them the correct messages in the store to which the paper now turns.

One of the perplexing problems of knowing mind-sets is the difficulty of assigning a random individual to a mind-set. The reason is simple, but profound. The mind-sets emerge out of the granularity of experience, and are based on the response of people to small, almost irrelevant pieces of communication. We are not talking about issues which are critical to the shopper, issues such as health, income, and so forth, and the decisions one makes about them. Those topics are sufficiently important to people to merit studies by academics and by interested professionals. A great deal of money is spent defining the preferences of a person, so that the sales effort can be successful. Not so with topics like cereal and yogurt, where there is knowledge, but little in the way of knowing the preferences of a particular shopper. Companies which manufacturer cereal and yogurt ‘know’ what to say, but the revenue to be made by knowing the preferences a randomly selected individual is too little to warrant deep investment.

To understand the preferences of a randomly selected individual may require one of two things. The first is extensive information about that individual, and a way to link that knowledge to one’s preference about what to say about cereal or about yogurt. That exercise could happen, at least for demonstration purposes, although it does not lend itself to being scaled, at least with today’s technology. Another way is to present the person, our shopper, with the right messages for that shopper. This latter approach requires a way to identify the shopper, and to assign the shopper to the proper mind-set, with low investment, in a way that can be done almost automatically. This second approach has to reckon with practicalities, such as the reluctance of the shopper to provide personal information, the potential disruption of the knowledge-gathering step to the shopping experience, and of course the need to find the appropriate motivation. The proposed process has to be simple, quick, easy to implement. Most of all, the process should motivate the shopper to participate.

The answer to the question of ‘how to assign a shopper to a mind-set’ comes from the use of a simple questionnaire called the PVI (personal viewpoint identifier; [5,6]. The PVI uses the data from the tables (2 and 4), to create a set of six questions having two answers (no/yes; not for me/for me, etc.) The questions come from the 16 elements, and are chosen to best differentiate between the two (or among the three) mind-sets. The important thing to keep in mind is that the PVI emerges directly from reanalysis of the data used to create the mind-sets. It will be the pattern of answers to the PVI which will assign a person to one of the mind-sets. With two products, and thus 12 questions, the PVI ‘step’ should take about a minute. The motivation might be lowered price for participants for some products, such as cereal and yogurt.

Figure 1 show the PVI, completed by the shopper at the start of the shopping effort or even ahead of visiting the store. Figure 2 shows a screen shot of the database, in which each shopper who participated is assigned to one of the two mind-sets for cereal, and one of the two mind-sets for yogurt.

FIG 1

Figure 1: The PVI (personal viewpoint identifier) for the cereal and yogurt, completed before the shopper begins, or completed at home. The website used to acquire the information is: https://www.pvi360.com/TypingToolPage.aspx?projectid=2317&userid=2

FIG 2

Figure 2: Example of a database attached to the PVI which records the mind-set to which the respondent belongs and the recommended types of messages for that mind-set

Here is a sequence of four proposed steps to test the approach:

  1. At the start of the shopping the individual could be invited to participate, by completing a short questionnaire on a computer, the PVI tool shown in Figure 1. The incentive could a special ‘participant’s pricing’ for the cereal or the yogurt. The objective is to get the shopper to participate, discover the shopper’s membership in a mind-set (in return for the promise of a lower price), and have the shopper interact, with the program assigning the shopper to the correct mind-set for one or several products. The opportunity further remains to engage the shoppers off-line, ‘type’ their preferences for dozens of products, and place ‘intelligent’ signage with the proper message for the two or three mind-sets emerging for each product. Thus the data would be granular, by person, and by product.
  2. Once the data has been acquired and put into the database, the shopper should be furnished a device linked to the database, with the shelf location linked both to the database, and to the shopper’s portable device.
  3. When the shopper reaches the appropriate store location, an ad for the product should be flashed on to the screen of the device, the ad possibly paid for by a vendor of yogurt or cereal. The ad should be the name of the vendor, the product type, and the appropriate message for the shopper, based upon the shopper’s assignment to the mind-set.
  4. The performance of the system can be measured by comparing the purchases of cereals and/or yogurt, comparing those who participated versus those who did not.

Selecting the Specific Messages to Show to the Shopper

Up to now we have focused on the science of the effort, figuring out the existence of mind-sets, the messages about cereal and yogurt to which they are most responsive, and then the creation of a simple tool, the PVI, to assign a person to a mind-set. We now face the most important task, selecting the messages that will be flashed to the shopper at the right time (e.g., when the shopper is passing the specific product and the objective is to get the shopper to select the product).

Keep in mind that up to now the effort to learn about the mind-set of the shopper has been brand-agnostic. That is, the objective has been to identify what messages differentiate the two kinds of cereal shoppers and the two kinds of yogurt shopper. In the real world, it is necessary to drive the shopper towards the appropriate brand, using the appropriate message.

If we remain with two mind-sets, and concentrate on shopping, we need not worry about Mind-Set 2. Mind-Set 2 for cereal has an additive constant of 68. They are ready to buy. They should be directed to the ‘brand’. It is Mind-Set 1 which must be convinced, since Mind-Set 1 has an additive constant of 38. They need motivating messages. Here are the two strongest messages for Mind-Set 1.

O2 A tasty breakfast choice makes it easy to maintain a healthy body weight         15

O4 Ideal choice for those concerned about eating too much sugar                     10

The same dynamics hold for yogurt. The additive constant is 72 for Mind-Set2, and 39 for Mind-Set 1. Mind-Set 2 is already primed to buy yogurt, and again should be directed to the ‘brand’. Mind-Set 1 with a low additive constant of 39 needs motivating messages, along with the brand. They have eight messages which score well in expected motivating power, and of those eight, three which score very well with coefficients 14 or higher.

F5 Made with natural flavoring                                         17

F4 So flavorful. it will satisfy your sweet taste                   16

C2 Comes in snack size.great for packed lunches               14

B2 Less sugar, less calories                                         12

C5 A hassle free healthy snack – goes where you go            12

B4 It’s good because IT’S REAL                                        11

C1 Ready to eat when you are                                         11

F2 Uses flavors to sweeten for a healthier you                   10

Discussion and Conclusions

One need only read the trade magazines about the world of retail to recognize that the world is becoming increasing aware of the potential of ‘knowledge’ to make a difference to growth and to profits. Over the past half century, knowledge of the consumer has burgeoned in all areas of business, with the knowledge often making the difference between failure and success, or more commonly today, the magnitude of success.

We are no longer living in a business world dominated by the opinions of one person in the management of a consumer-facing effort. Whereas decades ago it was common for the key executives to proclaim that they had a ‘golden tongue’ which could predict consumer behavior, today just the opposite occurs. Managers are afraid to decide without the support of consumer researchers, or as they title themselves, ‘insights professionals.’

At the level of shopping, especially when one buys something, ore even searches for something, there are programs which ‘follow’ the individual, selling the data to interested parities that use that information to offer their own version of that for which the individual was shopping. The tracking can be demonstrated by filling out a form or a product or service, not necessarily buying such a product. The outcome is a barrage of advertisements on the web for that product, from a few different vendors offering their special version.

The Mind Genomics approach presented here differs from the current micro-segmentation on the basis of previous behaviors demonstrated on the internet. Rather than watching what a person does to put the person into a specific grouping, or rather than applying artificial intelligence to the text material produced by the person, Mind Genomics moves immediately to granularity. The basic science of the topic (viz., messages for cereal, or messages for yogurt) is established at a convenient time, using language that the product manufacturer selects as appropriate for a customer. The important phrases and the relevant mind-sets are developed inexpensively, and rapidly, perhaps within a day. The PVI is part of that set-up. The next steps involve the shopper herself or himself. What emerges is a system wherein the shopper plays a simple but active role, and through a few keystrokes identifies the relevant group(s) to which she or he belongs. Once the shopper encounters the appropriate location, it is only a matter of sending the shopper the appropriate message. The ‘appropriate location’ can be the store shelf where the product is displayed, or on the web at an e-store, or even when the prospective shopper searches for the item. Both the item and the relevant motivating messages can be sent to the shopper, as long as the shopper’s membership in the appropriate mind-set can be determined.

References

  1. Schumann DW, Grayson J, Ault J, Hargrove K (1991) The effectiveness of shopping cart signage: Perceptual measures tell a different story. Journal of Advertising Research 31: 17-22.
  2. Dennis C, Michon R, Brakus JJ, Newman A, Alamanos E (2012) New insights into the impact of digital signage as a retail atmospheric tool. Journal of Consumer Behaviour 11: 454-466.
  3. Buttner OB, Florack A, Goritz AS (2013) Shopping orientation and mindsets: How motivation influences consumer information processing during shopping. Psychology & Marketing 30: 779-793.
  4. Chang CT, Cheng ZH (2015) Tugging on heartstrings: shopping orientation, mindset, and consumer responses to cause-related marketing. Journal of Business Ethics 127: 337-350.
  5. Gere A, Harizi A, Bellissimo N, Roberts D, Moskowitz H (2020) Creating a mind genomics wiki for non-meat analogs. Sustainability 12: 5352.
  6. Moskowitz H, Gere A, Moskowitz D, Sherman R, Deitel Y (2019) Imbuing the supply chain with the customer’s mind: today’s reality, tomorrow’s opportunity. Edelweiss Applied Sci Tech 3: 44-51.
  7. Gofman A, Moskowitz H (2010) Isomorphic permuted experimental designs and their application in conjoint analysis. Journal of Sensory Studies 25: 127-145.
  8. Likas A, Vlassis N, Verbeek JJ (2003) The global k-means clustering algorithm. Pattern recognition 36: 451-461.
fig 5

Flexible Electrochromic Devices based on Linear Monosubstituted Viologen Derivatives

DOI: 10.31038/NAMS.2022523

Abstract

Three monosubstituted viologen derivatives: 1-(4-indolylphenyl)-4,4′-bi-pyridine hexafluorophosphate (IV), 1-(4-phenothiazinylphenyl)-4,4′-bipyridine hexa-fluorophosphate (PV) and 1-(4-benzimidazolylphenyl)-4,4′-bipyridine hexafluoro-phosphate 1(BV), were synthesized. The electrochemical and electrochromic properties of these monosubstituted viologen derivatives were investigated. The flexible and rigid electrochromic devices (ECD) were prepared by using the synthesized viologen derivatives as active materials. The structure of the device is ITO-PET (or ITO-glass)/ electrochromic gel film/ITO-PET (or ITO-glass). The flexible and rigid ECDs exhibited reversible color changes under applied voltage. Upon applied voltage from 0.0 V to -1.4 V, IV-based flexible ECD exhibited optical contrast 33.5% at 564 nm, PV-based flexible ECD exhibited optical contrast 37.4% at 564 nm and BV-based flexible ECD exhibited optical contrast 45.8% at 466 nm.

Keywords

Monosubstituted viologen derivatives, Electrochromic, Electrochromic device, Flexible device, Optical contrast

Introduction

Electrochromism refers to the phenomenon that materials can exhibit reversible electrochemical oxidation or reduction and change their color reversibly under the application of appropriate voltage [1-3]. After years of development, the technology of electrochromism has been applied in some fields such as information display device [4], smart window [5] and anti-glare rearview mirror [6]. In general, electrochromic materials can be divided into inorganic and organic electrochromic materials. Inorganic electrochromic materials include transition metal oxides such as WO3 [7], NiO [8,9], MoO3 [10,11] and Prussian blue [12]. Organic electrochromic materials include small molecule optoelectronics materials [13], oligomer [14-16] and conjugated polymers [17-19]. As a typical of organic electrochromic materials, 1,1′-disubstituted-4,4′-bipyridinium salts (viologen) are widely reported due to their good electrochromic properties [20-25]. However, a large number of reports on viologen mainly focus on disubstituted viologen derivatives [26-29], and there are few reports on monosubstituted viologen derivatives [30,31].

In this paper, three monosubstituted monosubstituted viologen derivatives (Figure 1): 1-(4-indolylphenyl)-4,4′-bipyridine hexafluorophosphate (IV), 1-(4-phenothiazin-ylphenyl)-4,4′-bipyridine hexafluorophosphate (PV) and 1-(4-benzimidazolylphenyl)-4,4′-bipyridine hexafluorophosphate (BV), were synthesized. The electrochromic properties of these monosubstituted viologen derivatives were investigated.

fig 1

Figure 1: The molecular structural of three monosubstituted viologen derivatives

Materials and Methods

Materials

All the solvents were purified and dried using standard methods. Indole, phenothiazine, benzimidazole, 1-fluoro-4-nitrobenzene, 4,4’-bipyridine, 2,4-dinitrochlorobenzene, ammonium hexafluorophosphate (NH4PF6), 10% palladium on carbon (Pd/C), hydrazine hydrate and polymethylmethacrylate (PMMA) were purchased from Beijing HWRK Chem Co., Ltd. Ferrocene, tetrahydrofuran (THF), potassium carbonate (K2CO3) and N,N’-dimethylformamide (DMF) were purchased from Shanghai RichJoint Chemical Reagents Co., Ltd. Petroleum ether, ethanol, ethyl acetate, dichloromethane (DCM) and dimethyl sulfoxide (DMSO) were purchased from Shanghai Titan Scientific Co., Ltd. Methanol, propylene Carbonate (PC) and anhydrous tetra-n-butylammonium perchlorate (TBAP) were purchased from Sinopharm Chemical Reagent Co., Ltd. Indium tin oxide (ITO) glasses (10 Ω/sq) and ITO polyethylene terephthalate (PET, 30-35 Ω/sq) were purchased from Zhuhai Kaivo Optoelectronic Technology Co., Ltd.

Instrumentation

Nuclear magnetic resonance (NMR) spectra were recorded on a Bruker AVANCE-600 NMR spectrometer. Mass spectra were carried out on Bruker Agilent 1290 mass spectrometer. UV-vis spectra of compounds were measured on a Thermo Helios-γ spectrometer. Electrochemical properties of compounds were measured on CHI750A electrochemical workstation. A saturated calomel electrode (SCE), platinum wire, and ITO-glass were used as the reference electrode (RE), counter electrode (CE), and working electrode (WE), respectively. Electrochemical impedance spectroscopy (EIS) of ECDs was measured at a frequency in the range of 0.01 Hz–100 kHz on CHI750A electrochemical workstation to calculate the ionic conductivity of the prepared ion gels. Electrochromic properties of ECDs were measured on CHI750A electrochemical workstation and UV-vis spectrometer integrated with an electrochromic cyclic tester (Zhuhai Kaivo Optoelectronic Technology Co., Ltd.).

Synthesis

The synthetic routes to IV, PV and BV are shown in Scheme 1.

scheme 1

Scheme 1: Synthetic routes for the viologen derivatives

Compound 1

4,4’-Bipyridine (3.6 g, 23.0 mmol), 2,4-dinitrochlorobenzene (2.3 g, 11.7 mmol) and ethanol (60 mL) were added to a three-necked flask. The mixture was stirred at 80℃ in N2 atmosphere for 48 h. After the reaction, solution was cooled to room temperature, evaporated to give a crude product and washed with DCM (100 mL) to obtain grey solid (3.96 g, yield 94%). 1H NMR (D2O, 600 MHz, ppm) δ 9.41 (d, 1H), 9.27 (d, 2H), 8.96 (d, 1H), 8.84 (s, 2H), 8.70 (s, 2H), 8.31 (s, 1H), 8.04 (s, 2H).

Compound 2

Indole (1.1 g, 9.4 mmol), 1-fluoro-4-nitrobenzene (1.4 g, 9.9 mmol), K2CO3 (1.3 g, 9.4 mmol) and DMF (20 ml) were added to a three-necked flask. The mixture was stirred at 110°C for 24 h under a N2 atmosphere. After the reaction, solution was cooled to room temperature, cold water was added, precipitated and filtered to obtain crude product. The crude product was purified by silica gel column chromatography using ethyl acetate/petroleum ether (1:10, v/v) to obtain a yellow powder (1.96 g, yield 87%). 1H NMR (DMSO-d6, 600 MHz, ppm): δ 8.41 (d, 2H), 7.92 (d,2H), 7.83 (d,1H), 7.76 (d,1H), 7.70 (d, 1H), 7.29 (t, 1H), 7.21 (t, 1H), 6.83 (d, 1H).

Compound 3

Phenothiazine (2.0 g, 10.0 mmol), 1-fluoro-4-nitrobenzene (1.5 g, 10.6 mmol), K2CO3 (1.4 g, 10.1 mmol) and DMF (35 ml) were added to a three-necked flask. The mixture was stirred at 110°C for 24 h under a N2 atmosphere. After the reaction, solution was cooled to room temperature, cold water was added, precipitated and filtered to obtain crude product. The crude product was purified by silica gel column chromatography using DCM/petroleum ether (1:10, v/v) to obtain a yellow powder (2.85 g, yield 89%). 1H NMR (DMSO-d6, 600 MHz, ppm): δ 8.12 (d, 2H), 7.64 (d, 2H), 7.58 (d, 2H), 7.49 (t, 2H), 7.36 (t, 2H), 7.05 (d, 2H).

Compound 4

Benzimidazole (2.5 g, 21.1 mmol), 1-fluoro-4-nitrobenzene (3.3 g, 23.7 mmol), K2CO3 (3.3 g, 23.8 mmol) and DMF (60 mL) were added to a three-necked flask. The mixture was stirred at 110°C for 24 h under a N2 atmosphere. After the reaction, solution was cooled to room temperature, cold water was added, precipitated and filtered to obtain crude product. The crude product was purified by silica gel column chromatography using ethyl acetate/petroleum ether (1:2, v/v) to obtain a yellow powder (4.91 g, yield 96%). 1H NMR (DMSO-d6, 600 MHz, ppm) δ 8.75 (s, 1H), 8.47 (d, 2H), 8.04 (d, 2H), 7.80 (dd, 2H), 7.39 (dt, 2H).

Compound 5

2 (1.0 g, 4.2 mmol), 10% Pd/C (0.15 g), hydrazine hydrate (3.5 mL) and ethanol (65 ml) were added to a three-necked flask. The mixture was stirred at 80℃ in N2 atmosphere for 15 h. After the reaction, solution was filtered while hot, and the filtrate was evaporated to give a crude product. The crude product was purified by silica gel column chromatography using acetate/petroleum ether (1:4, v/v) to obtain a brown oily liquid (0.46 g, yield 53%). 1H NMR (DMSO-d6, 600 MHz, ppm): δ 7.61 (d, 1H), 7.44 (d, 1H), 7.37 (d, 1H), 7.17 (d, 2H), 7.15-7.11 (m, 1H), 7.09 – 7.04 (m, 1H), 6.72 (d, 2H), 6.59 (d, 1H), 5.30 (s, 2H).

Compound 6

3 (1.5 g, 4.7 mmol), 10% Pd/C (0.16 g), hydrazine hydrate (4 ml) and ethanol (40 ml) were added to a three-necked flask. The mixture was stirred at 80℃ in N2 atmosphere for 15 h. After the reaction, solution was filtered while hot, and the filtrate was evaporated to give a crude product. The crude product was purified by silica gel column chromatography using acetate/petroleum ether (1:10, v/v) to obtain a white solid (0.86 g, yield 63%). 1H NMR (DMSO-d6, 600 MHz, ppm): δ 7.00 (t,4H), 6.92 – 6.87 (m, 2H), 6.79 (t,4H), 6.21 (d, 2H), 5.43 (s, 2H).

Compound 7

4 (3.0 g, 12.7 mmol), 10% Pd/C (0.31 g), hydrazine hydrate (10 mL) and ethanol (60 ml) were added to a three-necked flask. The mixture was stirred at 80℃ in N2 atmosphere for 15 h. After the reaction, solution was filtered while hot, and the filtrate was evaporated to give a crude product. The crude product was purified by silica gel column chromatography using acetate/petroleum ether (1:1, v/v) to obtain a red oily liquid (2.37 g, yield 89%). 1H NMR (DMSO-d6, 600 MHz, ppm) δ 8.35 (s, 1H), 7.75 (dd, 1H), 7.46 (dd, 1H), 7.31-7.24 (m, 4H), 6.79-6.74 (m, 2H), 5.45 (s, 2H).

1-(4-Indolylphenyl)-4,4′-Bipyridine Hexafluorophosphate (IV)

1 (0.4 g, 1.1 mmol), 5 (0.3 g, 1.4 mmol) and ethanol (40 mL) were added to a three-necked flask. The mixture was stirred at 80℃ in N2 atmosphere for 48 h. After the reaction, solution was cooled to room temperature, evaporated to give a crude product and washed with DCM (100 mL) to give orange solid. The crude product was dissolved in water/methanol (1:1, v/v) to obtain saturated solution. NH4PF6 (1.7 g) was added to the solution. The mixture was stirred at room temperature for 0.5h, and then the mixture was filtered to obtain yellow solid (0.38 g, yield 68%). 1H NMR (DMSO-d6, 600 MHz, ppm) δ 9.63 (d, 2H), 8.93 (d, 2H), 8.87 (d, 2H), 8.20 (dd, 4H), 8.04 (d, 2H), 7.83 (d, 1H), 7.72 (d, 2H), 7.30 (t, 1H), 7.21 (t, 1H), 6.83 (d, 1H). 13C NMR (DMSO-d6, 151 MHz, ppm) δ 153.6, 151.6, 145.9, 141.8, 141.1, 140.1, 135.3, 130.1, 128.9, 127.0, 125.8, 124.9, 123.4, 122.6, 121.7, 121.4, 110.9, 105.4. HRMS (ESI) C24H18N3+ found [M]+: 348.1509, calcd. 348.1495.

1-(4-Phenothiazinylphenyl)-4,4′-Bipyridine Hexafluorophosphate (PV)

1 (0.2 g, 0.5 mmol), 6 (0.2, 0.7 mmol) and ethanol (50 mL) were added to a three-necked flask. The mixture was stirred at 80℃ in N2 atmosphere for 48 h. After the reaction, solution was cooled to room temperature, evaporated to give a crude product and washed with DCM (100 mL) to give orange solid. The crude product was dissolved in water/methanol (1:1, v/v) to obtain saturated solution. NH4PF6 (0.8 g) was added to the solution. The mixture was stirred at room temperature for 0.5 h, and then the mixture was filtered to obtain yellow solid (0.12 g, yield 55%). 1H NMR (DMSO-d6, 600 MHz, ppm) δ 9.57 (d, 2H), 8.92 (d, 2H), 8.85 (d, 2H), 8.20 (d, 2H), 8.04 (d, 2H), 7.53 (d, 2H), 7.38 (d, 2H), 7.25 (t, 2H), 7.14 (t, 2H), 6.90 (d, 2H). 13C NMR (DMSO-d6, 151 MHz, ppm) δ 153.3, 151.5, 145.8, 145.7, 142.5, 141.1, 139.2, 128.4, 128.1, 127.4, 126.6, 125.8, 125.4, 124.9, 122.6, 122.0. HRMS (ESI) C28H20N3S+ found [M]+: 430.1388, calcd. 430.1372.

1-(4-Benzimidazolylphenyl)-4,4′-Bipyridine Hexafluorophosphate (BV)

1 (0.9 g, 2.5 mmol), 7 (0.9 g, 4.3 mmol) and ethanol (40 mL) were added to a three-necked flask. The mixture was stirred at 80℃ in N2 atmosphere for 48 h. After the reaction, solution was cooled to room temperature, evaporated to give a crude product and washed with DCM (100 mL) to give yellow solid. The crude product was dissolved in water/methanol (1:1, v/v) to obtain saturated solution. NH4PF6 (4.0 g) was added to the solution. The mixture was stirred at room temperature for 0.5 h, and then the mixture was filtered to obtain yellow solid (0.58 g, yield 66%). 1H NMR (DMSO-d6, 600 MHz, ppm) δ 9.62 (d, 2H), 8.93 (d, 2H), 8.87 (d, 2H), 8.76 (s, 1H), 8.23 (d, 2H), 8.20 (d, 2H), 8.16 (d, 2H), 7.80 (dd, 2H), 7.41 (dt, 2H). 13C NMR (DMSO-d6, 151 MHz, ppm) δ 153.81 (s), 151.61 (s), 146.05 (s), 144.44 (s), 143.82 (s), 141.34 (s), 141.04 (s), 138.75 (s), 133.13 (s), 127.27 (s), 125.76 (s), 125.13 (s), 124.46 (s), 123.49 (s), 122.57 (s), 120.69 (s), 111.23 (s). HRMS (ESI): [C23H17N4+]+: 349.1452, calcd. For 349.1448.

The Fabrication of Electrochromic Devices

Two ITO-PET (2 cm × 5 cm, or ITO-glass: 2 cm × 3 cm) were used as the working electrode and the counter electrode, respectively. Electrochromic gel (TBAP: PMMA: PC=3:7:90, w/w) contain 0.01 M monosubstituted viologen derivatives and 0.01 M ferrocene was injected into the sealing device. The thickness of the electrochromic gel film is 1 mm. The structure of the device was ITO-PET (or ITO-glass)/electrochromic gel film/ITO-PET (or ITO-glass). EIS of rigid ECDs based on IV, PV and BV are shown in Figure S17(a)-(c). Figure S17(d) is the corresponding analog equivalent circuit. Rs is resistance of the gel electrolyte. Rct is charge transfer resistance. CPE is double-layer capacitance. Zw is Warburg impedance. According to formula (1), ionic conductivity (σ) of IV, PV and BV-based gel were 1.21×10-5 S/cm, 1.59×10-5 S/cm and 1.88×10-5 S/cm, respectively. S is area of gel film (Scheme 2).

σ=d/(Rs×S)                            (1)

scheme 2

Scheme 2: Structure diagram of electrochromic device

Results and Discussion

Optoelectrochemical Properties of Monosubstituted Viologen Derivatives

Cyclic voltammograms (CVs) of IV, PV and BV were recorded at a scan rate of 50 mV/s in PC solution containing 0.1 M TBAP. As is shown in Figure S18, the initial reduction potentials (Eredonset) of IV, PV and BV were -0.64 V, -0.19 V and -0.24 V, respectively. UV-Vis absorption spectra of IV, PV and BV in PC solution are shown in Figure S19. The absorption peaks(λmax)of IV, PV and BV were located at 361, 394/424 and 333/421 nm, respectively. The band edge wavelength (λedge) of IV, PV and BV were 496, 564 and 434 nm respectively. According to formula (2), (3) and (4), optical band gap (Egopt), HOMO energy levels (EHOMO) and LUMO energy levels (ELUMO) of monosubstituted viologen derivatives were calculated. Table S1 shows the optoelectrochemical properties of IV, PV and BV.

Egopt = 1240/λedge                           (2)

ELUMO=-e(Eredonset+4.4)                    (3)

EHOMO=ELUMO-Egopt                           (4)

Electrochromic Properties of ECDs based on Monosubstituted Viologen Derivatives

Figure 2 shows CVs of flexible ECDs based on the monosubstituted viologen derivatives at a scan rate of 50 mV/s. All CVs of flexible ECDs exhibited one pair of redox peaks during the redox process which corresponded to the redox processes of monosubstituted viologen derivatives. The reduction peaks of flexible ECDs based on IV, PV and BV were -1.61, -1.64 and -1.52 V, respectively, which correspond to the reduction of cations to neutral state of monosubstituted viologen derivatives. Rigid ECDs based on monosubstituted viologen derivatives were fabricated by using ITO-glass instead of ITO-PET. As is shown in Figure S20, flexible and rigid ECDs based on monosubstituted viologen derivatives exhibited the same redox behavior.

fig 2

Figure 2: CVs of (a) IV-based flexible ECD, (b) PV-based flexible ECD and (c) BV-based flexible ECD at a scan rate of 50 mV/s

The spectroelectrochemistry of flexible ECDs based on viologen derivatives under different applied voltages and the color change of flexible ECDs are shown in Figure 3. With the increase of applied voltage, the transmittance of flexible ECDs based on synthesized viologen derivatives in the visible region decreased. For flexible ECD based on IV, it was yellow under no voltage applied. When the applied voltage was -1.4 V, it exhibited a color change from yellow to orange. For flexible ECD based on PV, it was yellow under no voltage applied. When the applied voltage was -1.4 V, it exhibited a color change from yellow to orange red. For flexible ECD based on BV, it was light yellow under no voltage applied. When the applied voltage was -1.4 V, it exhibited a color change from light yellow to light brown. The spectroelectrochemistry of flexible ECDs based on monosubstituted viologen derivatives showed that three kinds of flexible ECDs had reversible color change, which indicated the introduction of groups of indole, phenothiazine and benzimidazole can effectively adjust the electrochromic properties of viologen derivatives. In addition, under the bending state, the flexible ECDs still exhibited reversible color change under the applied voltage.

fig 3

Figure 3: Spectroelectrochemistry of (a) IV-based flexible ECD, (b) PV-based flexible ECD and (c) BV-based flexible ECD under different applied voltages and the image of corresponding devices

The optical contrast is defined as difference of transmittance under different applied voltage at the same wavelength. According to Figure 3, the optical contrast of the flexible ECDs based on IV, PV and BV reached 33.5% (564 nm), 37.4% (564 nm) and 45.8% (466 nm) , respectively. As is shown in Figure S21, the electrochromism of rigid ECDs was consistent with that of flexible ECDs. The optical contrast of the rigid ECDs based on IV, PV and BV reached 42.4% (582 nm), 44.1% (584 nm) and 44.0% (568 nm), respectively.

Switching time is defined as time required for the current to change by 95% under the applied voltage. Switching time includes response time from bleached state to colored state (coloring time) and response time from colored state to bleached state (bleaching time), which was measured using double-step chronoamperometry. The current-time curves of flexible ECDs based on IV, PV and BV are shown in Figure 4. For flexible ECD based on IV, the coloring and bleaching times were 46.0 s and 4.9 s, respectively. For flexible ECD based on PV, the coloring and bleaching times were 84.2 s and 9.9 s, respectively. For flexible ECD based on BV, the coloring and bleaching times were 52.9 s and 7.5 s, respectively. The current-time curves of rigid ECDs based on IV, PV and BV are shown in Figure S22. The results showed that the coloring times of flexible ECDs were longer than those of rigid ECDs. The reason may be that ITO-PET has higher surface resistance than that of ITO-glass, which makes it difficult for cations to get electrons at the cathode.

fig 4

Figure 4: Current-time curves of (a) IV-based flexible ECD, (b) PV-based flexible ECD and (c) BV-based flexible ECD (switched upon voltages between 0.0 V and -1.4 V with a switching interval of 120 s)

The stability of flexible ECDs based on 2IV, 2PV and 2BV were also measured using chronoamperometry. As is shown in Figure 5, the flexible ECD based on IV, PV and BV remained 51.1%, 97.6% and 72.7% of the original electric charge after 1000 cycles, respectively. The stability of rigid ECDs based on 2IV, 2PV and 2BV was shown in Figure S23. All the ECDs exhibited suitable cyclic stability.

fig 5

Figure 5: Properties in write-erase ability of (a) IV-based flexible ECD, (b) PV-based flexible ECD and (c) BV-based flexible ECD

The coloration efficiency (η) refers to the ratio of the change of optical density to charge at a specific wavelength which is used to measure the charge utilization of the device. According to Formula (5), coloration efficiency of ECDs based on IV, PV and BV was calculated. Flexible ECDs based on IV, PV and BV have coloration efficiency of 129.67 cm2/C (564 nm), 87.78 cm2/C (564 nm) and 107.22 cm2/C (466 nm), respectively. Rigid ECDs based on IV, PV and BV have coloration efficiency of 197.84 cm2/C (582 nm), 198.70 cm2/C (584 nm) and 201.50 cm2/C (568 nm), respectively. Electrochromic properties of ECDs based on 2IV, 2PV and 2BV are presented in Table S2.

η = ΔOD/Q; ΔOD = log (Tb/Tc)                         (5)

ΔOD is the change in optical density; Q is the amount of charge injected (or extracted) per unit area (C/cm2); Tc is the transmittance (%) of the colored state; Tb is the transmittance (%) of the bleached state.

Conclusion

In summary, three monosubstituted viologen derivatives IV, PV and BV were synthesized and corresponding flexible and rigid electrochromic devices were fabricated. All flexible and rigid ECDs exhibited reversible color changes upon applied voltage. In addition, flexible ECDs still exhibited reversible color change under bending state. IV-based flexible ECD exhibited reversible color changes from yellow to orange upon applied voltage from 0.0 V to -1.4 V, and it exhibited optical contrast 33.5% at 564 nm. PV-based flexible ECD exhibited reversible color changes from yellow to orange red upon applied voltage from 0.0 V to -1.4 V, and it exhibited optical contrast 37.4% at 564 nm. BV-based flexible ECD exhibited reversible color changes from light yellow to light brown upon applied voltage from 0.0 V to -1.4 V, and it exhibited optical contrast 45.8% at 466 nm. All ECDs exhibited suitable switching time and suitable coloration efficiency.

Author Contributions

Weijie Ye: Methodology, Formal analysis, Investigation, Writing-original draft, Conceptualization, Software, Data curation. Xu Guo: Visualization. Peng Wang and Chao Qian: Validation. Ping Liu: Resources, Writing-review and editing, Supervision, Project administration, Funding acquisition.

Funding

This research was financially supported by the NSFC (Grant no. 20674022, 20774031, and 21074039), the Natural Science Foundation of Guangdong (Grant no. 2014A030313241, 2014B090901068, 2016A010103003, and 2021A1515010929), and the Ministry of Education of the People’s Republic of China (Grant no. 20090172110011).

Data Availability Statement

The authors confirm that the data supporting the findings of this study are available within the article.

Conflicts of Interest

There are no conflicts to declare.

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fig 1

Prevalence and Associated Factors of Bronchial Asthma among Adult Patients in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, Jigjiga, Somali region, Ethiopia 2020

DOI: 10.31038/PEP.2022311

Abstract

Background: The magnitude of asthma in developing countries increased in 50% per decade for the last 40 years and approximately 250,000 deaths occur in each year. It was the common conditions that affected 5-10% of the population during the past 20 years.

Objectives: The aim of this study was to assess the Prevalence and associated factors of bronchial asthma among adult patients in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, Jigjiga, Somali Region, Ethiopia 2020.

Methods: Hospital based cross sectional study design was conducted at Sultan Hassan yabare referral hospital during May-June 2020. Three hundred fifty two (352) patients who visited adult OPD over two months period were included in the study using simple random sampling. The data was checked for completeness, cleaned and then entered into Epi-data version 3.1 then exported to SPSS version 23 for analysis. Bivariate & multivariate binary logistic regression analysis was used to see the associations between bronchial asthma and factors. Adjusted odd ratios were measured at 95% confidence level and P-Value of less than 0.05 was considered significant.

Result: Prevalence of bronchial asthma among adult patients was 9.4%. Being an urban resident (AOR: 3.425:95% CI 1.036-11.319), having family history of asthma (AOR: 5.796: 95% CI 2.31-, 14.540), and presence of vermin in the house (AOR: 2.999: 95% CI 1.106-8.129) were significantly associated with bronchial asthma. The authors concluded that the prevalence of bronchial asthma among adult patients was high. Therefore, educational program about the risk factors and preventive measures of asthma are highly recommended.

Keywords

Adult patient, Bronchial asthma, Shiekh Hassan Yabere Referral Hospital, Jigjiga, Ethiopia

Introduction

Asthma is defined as a “chronic inflammatory disease of the airways” that can cause any or all of the following symptoms: -shortness of breath, tightness in the chest, coughing and wheezing [1]. The chronic inflammation is associated with airway hyper responsiveness that leads to recurrent episodes of wheezing, breathlessness, chest tightness and coughing, particularly at night or in the early morning. These episodes are usually associated with widespread, but variable airflow obstruction within the lung that is often reversible either spontaneously or with treatment [2].

Asthma imposes a large burden on the individual and on health care systems. Currently, asthma prevalence is approximately 10%-13%globaly. Unexplained temporal and geographic variations in asthma prevalence have been reported with asthma prevalence increasing over the past few decades [3].

In Africa, problems including those arising from the over-utilization of health services, lack of trained staff and diagnostic apparatus, and non-availability and unaffordability of inhaled medications have hindered efforts to improve the management of asthma. The lack of organized health promotion programs, such as effective control strategies for environmental triggers, air pollutants, and occupational dusts have also contributed to the growing burden [4].

WHO has reported that the levels of asthma control and health responses in the continent have been below recommended standards, and that have contributed to the size of the disease burden [4]. In addition, though many African countries have national guidelines for the management of asthma and other CRDs, these guidelines has not been implemented in most rural areas . Economic analyses in many African settings have shown that direct costs from asthma are usually greater than the indirect costs. It has been suggested that education of health care providers and the public is a vital element of the response to the challenge posed by asthma in Africa [4].

The prevalence of asthma in developing countries increased in 50% per decade for the last 40 years and approximately 250,000 deaths occur in each year. It was the common conditions that affect 5-10% of the population during the past 20 years [5].

Bronchial asthma is one of the most common public health problems in Ethiopia. Its prevalence increased over the last few decades with different contributing factor such as cigarette smoking [6], household economic status [7], occupational condition of the patients [7], residence of the patients [8], presence of vermin at household [7] and family history of asthma [9]. It is coming another burden for the country next to those communicable diseases [10]. In one study conducted, in south west Ethiopia, asthma accounted for 2% of outpatient and 5.4% of medical admission [10], and different risk factors are responsible for this problem like poor compliance for the drugs, lack of awareness about the disease, low socio economic status and hyper sensitivity [3].

There is significant physical and socio-economic burden with asthma related health cost. It results is an estimated 420,000 deaths every year [11]. In developing countries, where poverty and non-communicable respiratory disease have long been linked Bronchial asthma is often diagnosed after a long time because of the patients low medical seeking behavior. This may be an important factor for increasing morbidity and mortality as a result of asthma [12,13]. It represents a substantial economic and social burden throughout the world [14]. In developing countries, an additional problem is that health planners have limited resources hence it is one of the factors for emergency department visit [15,16].

The global initiative for asthma (GINA) estimates that the global prevalence of asthma ranges from 1 to 18% [17]. In study conducted in Portugal Prevalence of diagnosed asthma was 5.0% and the ‗Lifetime asthma ‘prevalence was 10.5%. The prevalence was similar in men and women and in all age [18], and another study done In the Kingdom of Saudi Arabia in 2001, the prevalence of asthma was 12% [19]. In Malaysia, it was estimated that there is 1.6 to 2 million asthmatics in 1996 and was leader cause for outpatient visit [20].

Factors that contribute to the bronchial asthma and associated factors among adult patients has not been studied earlier in Somali region. So, the aim of this study was to determine the prevalence and associated factors of bronchial asthma among adult patients in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital.

Methods and Materials

Study Area and Study Period

The study was conducted in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, which is the only referral hospital in the region found in Jigjiga town capital of Somali region. It is located 636 km eastern of Addis Ababa (the capital city of Ethiopia). According to 2007 Central Statistical Agency census report, the projected population of Jigjiga town in 2019 is 166,664 of whom 5267 (3.16%) and 16833 (10%) pregnant women and children aged 6-59 months respectively. The study was conducted from May to June 2020.

Study Design

Institution based cross sectional study design was employed.

Source and Study Population

Source Population

All adult patients who visited adult OPD and adult emergency department of Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital during the study period were source population.

Study population

Randomly selected adult patients who visited adult emergency department and adult OPD of Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital during the study period were study population.

Inclusion and Exclusion Criteria

Inclusion criteria

Adult patients who were visited adult OPD and adult emergency were included in the study.

Exclusion criteria

Patients that were unable to respond or serious illness were excluded from the study.

Sample Size Determination

The sample size was determined using single population formula Assumptions: 95% confidence interval, 5% margin of error and proportion prevalence of bronchial asthma (29.6%) from Debre Berhan ,Ethiopia [7].

for 1

Where: n= the minimum sample size required for the study

Z= standard normal distribution (Z=1.96) with 95% confidence interval

P= prevalence of bronchial asthma (0.296) .(7)

d=is a tolerable margin of error (d=5%=0.05)

for 2

Then by adding 10% (0.1) non-response rate, the total sample size (n) is n=320+ (320×0.1) =320+32=352. Final Sample size is to be 352.

Sampling Techniques and Procedures

Systematic sampling technique was used to select study participants. Jigjiga University Sultan Sheikh Yabere Referral Hospital was selected purposefully. First the average monthly adult patient visiting emergency department calculated which was 1052 adult patient visited Emergency. So eligible patients were recruited using systematic sampling technique. Every K interval calculated i.e. K= 1052 /352=3, so that every third patient was included until the required sample size was achieved. The first patient was taken using lottery method.

Data Collection Tools and Methods

The data was collected using structured questionnaires by interviewing the respondents. The questionnaires was initially prepared in English and then translated into Somali and then back translated into English to check for any inconsistencies or distortion in the meaning of words and concepts. Five Nurse Data collectors and two supervisors were recruited and training was provided on the tools, data collection procedures, the objectives, questionnaires and ways of conducting interview by the principal investigator for two days before the actual data collection time.

Study Variables

Dependent Variable

Bronchial asthma in Adult Patients.

Independent Variables

Socio-demographic factors

  • Age,
  • Sex,
  • Income,
  • occupational,
  • Family literacy status,
  • Residence,
  • cost,

Individual behavior and health‑ related condition

  • Smoking status
  • Co -morbid disease (COPD, Pneumonia, other chronic disease, recurrent URTI

Environmental and housing characteristics of the study participants

  • Vermin

Data Quality Control

Data quality was assured through training of data collectors, the questionnaire was evaluated by experts to assess its relevance, and their comments were taken in consideration then questionnaire had pretested on another facility before beginning the actual data collection process and continuous supervision at the time of data collection was conducted. Supervisors together with principal investigator discussed findings of pretest questionnaires checked and modified before the actual data collection. The collected questionnaire was checked in each day on the actual data collection time for completeness and consistency by supervisors and principal investigator. Code was given for completed questionnaire. Double data entry was done to make comparisons of two data clerks and resolve if there was being some difference,

Data Processing and Analyses

The data was coded and entered using Epi-data version 7.2.3.1 then exported, processing and analyzing were done using SPSS version 23. Descriptive statistics of different variables were done by cross tabulation. Binary logistic regression models using bivariate [crude odds ratio, [COR] and multivariable analysis [adjusted odds ratio, AOR] with 95% Confidence interval [CI] were used. From the bivariate analysis, variables that has with a significance level of p<0.25 was being retained for inclusion into the multivariable analysis in the final model. Variables with p<0.05 with being considered as statistically significant and independently associated with bronchial asthma.

Ethical Consideration

An ethical clearance was obtained from Ethics Review Committee of Jigjiga University School of Graduate studies. Written and verbal consent was obtained from each participant after explaining the purpose and nature of the research. Participation in the study was on a voluntary basis and participants were informed their right to quit their participation at any stage of the study if they did not want to continue. Moreover, confidentiality of the information was assured by using an anonymous questionnaire.

Results

Socio-Demographic Characteristics of the Study Participants

Three hundred fifty-two study participants primarily sampled for the study, 340 have participated in the study they made a response rate of 96.7%. The reason for non-response was not willing to participate in the study. The mean age of the study participants was 28.08 with SD of +6.139. The age range of the study participants were 15 and 47 years respectively. One hundred seventy-one (50.3%) males and 169 (49.7%) females were participated in the study. Major ethnic group of this study participant 313 (92.1%) were Somali. About 296 (87.1%) were living in urban and 258(75.9%) were married by their marital status. Most of the study participants 277 (81.7%) were categorized under middle income (Table 1).

Table 1: Distribution of Socio-Demographic Characteristics of the Study Participants in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, Jigjiga, Somali region, Ethiopia 2020 G.C.

Variable

Category Frequency

 (No)

Percentages

 (%)

Age of the patient 15-24

77

22.7

25-34

83

24.6

35-44

78

23.1

45-54

55

16.1

>=55

46

13.6

Marital status 1. Single

72

21.2

2. Married

258

75.9

3. Divorced

6

1.8

4. Widowed

4

1.2

Sex 1. Male

171

50.3

2. Female

169

49.7

Residence 1. Urban

296

87.1

2. Rural

44

12.9

Ethnicity

 

1. Somali

313

92.1

2. Amhara

17

5.0

3. Gurage

4

1.2

4. Others

6

1.8

Occupational status 1. Government employee

30

8.8

2. Farmer

57

16.8

3. Daily laborer

61

17.9

4. Marchant

20

5.9

5. Others

172

50.6

Family income 1. High

55

16.2

2. Middle

277

81.5

3. Low

8

2.4

Presenting Symptoms

Most of the study participants the commonest presenting asthma symptom was cough reported by 24.4 % of the patients. The second common symptoms were also rhinitis and sinusitis reported by 18.5% and 17.4% of the patients respectively while the least presenting symptoms were atopic dermatitis 13.5% reported by the patients (Table 2).

Table 2: Distribution of presenting symptoms of the Study Participants in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, Jigjiga, Somali region, Ethiopia 2020 G.C.

Variable

Category Frequency (No)

Percentages (%)

Wheezing 1. Yes

55

16.2

2. No

285

83.8

Cough 1. Yes

83

24.4

2. No

257

75.6

Dyspnea (shortness of breath) 1. Yes

37

10.9

2. No

303

89.1

Rhinitis

1. Yes

63

18.5

2. No

277

81.5

Sinusitis 1. Yes

59

17.4

2. No

281

82.6

Atopic dermatitis 1. Yes

46

13.5

2. No

294

86.5

Cyanosis 1. Yes

55

16.2

2. No

285

83.8

Health Related Characteristics

Among the participants, 37.7% had family history of asthma. Fifty-six (21.8%) of the study participants had an experience of pneumonia in the last 12 months (Table 3).

Table 3: Distribution of health related characteristics of the Study Participants in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, Jigjiga, Somali region, Ethiopia 2020 G.C.

Variable

Category Frequency

 (No)

Percentages

 (%)

Does a patient diagnosis for asthma For now or before? 1. Yes

32

9.4

2. No

308

90.6

Family history of asthma?

 

1. Yes

178

52.4

2. No

162

47.6

3. don’t know
Do you think that is there anything that triggers your asthma?

 

1. Yes

32

9.4

2. No

308

90.6

3. don’t know
If yes to Q.no 303, what are your trigger factors that exacerbate your asthma?

 

1. Dust

4

1.2

2. Smoke

12

3.5

3. Cold weather

14

4.1

4. Strong smell

2

0.6

5. Other (s)

4

1.2

Have you ever faced any asthma exacerbation symptoms in the last 12 month 1. Yes

32

9.4

2. No

308

90.6

3. don’t know    
Bronchodilators drug utilization

1. Yes

155

45.6

2. No

185

54.4

Experienced of drug discontinuation 1. Yes

15

4.4

2. No

325

95.6

History of Chronic diseases like CHD 1. Yes

37

10.9

2. No

303

89.1

Presence of pneumonia in the last 12 months 1. Yes

37

10.9

2. No

303

89.1

Individual Behavior

Fifty-four (15.9%) of the study participants were ever smoke cigarette while 38(11.2%) were currently smokers. Among the participants, 24(7.4%) had habit of frequent utilization of perfume and 55(16.2%) had no habit of exercise (Table 4).

Table 4: Distribution of individual behavior of the Study Participants in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, Jigjiga, Somali region, Ethiopia 2020 G.C.

Variable

Category Frequency

 (No)

Percentages

 (%)

Do you ever smoke cigarette?

 

1. Yes

54

15.9

2. No

286

84.1

Are you currently a smoker?

 

1. Yes

38

11.2

2. No

302

88.8

Do you think that is there anything that limits your daily activities?

 

1. Yes

55

16.2

2. No

285

83.8

Is your habit of frequent usage of perfume 1. Yes

25

7.4

2. No

315

92.6

Environmental Factors

More than half of the study participants 188(55.3%) their house have vermin/dust. Three hundred-ten (91.2%) households used charcoal as source of energy, followed by electricity 6.2%, kerosene 1.5% and wood only 1.2%. Almost all of the study participants 340(100%) reported that did not use biomass fuel (Table 5).

Table 5: Distribution of environmental factors of the Study Participants in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, Jigjiga, Somali region, Ethiopia 2020 G.C.

Variable

Category Frequency

 (No)

Percentages

 (%)

Is there presence of vermin/dust in the home?

 

1. Yes

188

55.3

2. No

152

44.7

How many rooms are there in your house (Including the sitting room)? 1.>4 rooms

262

77.1

2.<4 rooms

78

22.9

Number of windows in the house 1. Yes

119

35.0

2. No

221

65.0

With what type of fuel source do you cook at home?  1. Charcoal

310

91.2

2. Wood

4

1.2

3. Electricity

21

6.2

4. Kerosene

5

1.5

Did you use biomass fuel for work or home? 1. Yes

0.00

0.00%

2. No

340

100%

Prevalence of Bronchial Asthma

In this study the overall prevalence of bronchial asthma among adult patients in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital Somali region was found 9.4%with (95%CI: 6.5, 12.9) (Figure 1).

fig 1

Figure 1: Prevalence of bronchial asthma in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, Jigjiga, Somali region, Ethiopia 2020.

Factors Associated with Bronchial Asthma

Bi-variable Analyses on Factors Associated with Bronchial asthma

In the variables included in Bivariate analyses were: Residence, Wheezing, Cough, Dyspnea (shortness of breath), Rhinitis, Sinusitis, atopic dermatitis, Family history of asthma and Presence of vermin/dust in the home.

This study revealed that urban residents were 3.726 times [COR=3.726; 95%CI: (1.274, 10.903)] more likely to develop bronchial asthma than rural residents.

This study indicated that patients who come from the family history of asthma were 6.625 times [COR=6.625; 95%CI: (2.872, 15.280)] more likely to develop bronchial asthma than from non-asthmatic family.

In this study, presence of vermin at household level were 2.694 times [COR=2.694; 95%CI: (1.072, 6.768)] increased the probability of developing asthma among adult patients (Table 6).

Table 6: Bi-variable Analyses for Factors affecting Bronchial asthma among Adult Patients in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, Jigjiga, Somali region, Ethiopia 2020.

Variable

Category Bronchial asthma COR (95%CI) P-value
Yes

No (%)

No

No (%)

Residence 1. Urban

28 (12.2)

201 (87.8) 3.726 (1.274, 10.903) 0.016

2. Rural

4 (3.6) 107 (96.4)

1.00

Wheezing 1. Yes

8 (14.0)

49 (86.0) 1.762 (0.748, 4.149) 0.195

2. No

24 (8.5) 259 (91.5)

1.00

Cough 1. Yes

11 (13.3)

72 (86.7) 1.717 (0.790, 3.730) 0.172

2. No

21 (8.2) 236 (91.8)

1.00

Dyspnea (shortness of breath) 1. Yes

6 (5.2)

31 (83.8) 2.062 (0.788, 5.397) 0.140

2. No

26 (8.6) 277 (91.4)

1

Rhinitis 1. Yes

12 (19.0)

51 (81.0) 3.024 (1.391, 6.571) 0.005

2. No

20 (7.2) 257 (92.8)

1

Sinusitis 1. Yes

14 (24.7)

45 (76.3) 4.546 (2.112, 9.785) 0.000

2. No

18 (5.4) 263 (93.6)

1

Atopic dermatitis 1. Yes

7 (15.2)

39 (84.8) 1.931 (0.783, 4.764) 0.153

2. No

25 (8.5) 269 (91.5)

1.

Family history of asthma 1. Yes

24 (20.0)

96 (80.0) 6.625 (2.872, 15.280) 0.000

2. No

8 (3.6) 212 (96.4)

1.00

Is your habit of frequent usage of perfume 1. Yes

7 (19.4)

29 (80.6) 3.756 (1.503, 9.381) 0.035

2. No

25 (7.2) 279 (91.8)

1.00

Presence of vermin/dust in the home 1. Yes

26 (13.6)

165 (86.4) 2.694 (1.072, 6.768) 0.005

2. No

6 (4.0) 143 (96.0)

1.00

Multivariable Analyses on Factors Associated with Bronchial asthma

Those variable which had association during bivariate analysis and other candidate variables with P<0.25 in the bivariate analysis were included in the final model of multivariate analysis in order to control all possible confounders. In multivariable analyses, in multivariable logistic regression analysis revealed that sinusitis, residence, family history and vermin/dust were risk factors significantly associated with bronchial asthma.

This study revealed that urban residents were 3.425 times [AOR=3.425; 95%CI: (1.036, 11.319)] more likely to develop bronchial asthma than rural residents.

This study indicated that patients who come from the family history of asthma were 5.796 times [AOR=5.796; 95%CI: (2.311, 14.540)] more likely to develop bronchial asthma than from non-asthmatic family.

In this study, present of vermin at household level were 2.999 times [COR=2.999; 95%CI: (1.106, 8.129)] increased the probability of developing asthma among adult patients.

This study indicated that patients who have sinusitis were 2.971 times [AOR=2.971; 95%CI: (1.193, 7.397)] more likely to develop bronchial asthma than from non-sinusitis (Table 7).

Table 7: Multivariable Logistic Regression Analyses for Factors Bronchial asthma among Adult patients in Jigjiga University Sultan Sheikh Hassan Yabere Referral Hospital, Jigjiga, Somali region, Ethiopia 2020 G.C.

Variable

Category Dx of Bronchial asthma COR (95%CI) AOR (95%CI)
Yes

No (%)

NO

No (%)

Residence 1. Urban

28 (12.2)

201 (87.8) 3.726 (1.274, 10.903) 3.425 (1.036, 11.319)

2. Rural

4 (3.6) 107 (96.4) 1.00

1.00

Wheezing 1. Yes

8 (14.0)

49 (86.0) 1.762 (0.748, 4.149) 2.240 (0.822, 6.104)

2. No

24 (8.5) 259 (91.5) 1.00

1.00

Cough 1. Yes

11 (13.3)

72 (86.7) 1.717 (0.790, 3.730) 1.597 (0.597, 4.273)

2. No

21 (8.2) 236 (91.8) 1.00

1.00

Dyspnea (shortness of breath) 1. Yes

6 (5.2)

31 (83.8) 2.062 (0.788, 5.397) 1.924 (0.578, 6.400)

2. No

26 (8.6) 277 (91.4) 1

1.00

Rhinitis 1. Yes

12 (19.0)

51 (81.0) 3.024 (1.391, 6.571) 1.847 (0.690, 4.949)

2. No

20 (7.2) 257 (92.8) 1

1.00

Sinusitis 1. Yes

14 (24.7)

45 (76.3) 4.546 (2.112, 9.785) 2.971 (1.193, 7.397)

2. No

18 (5.4) 263 (93.6) 1

1.00

Atopic dermatitis 1. Yes

7 (15.2)

39 (84.8) 1.931 (0.783, 4.764) 1.387 (0.481, 4.002)

2. No

25 (8.5) 269 (91.5) 1

1.00

Family history of asthma 1. Yes

24 (20.0)

96 (80.0) 6.625 (2.872, 15.280) 5.796 (2.311, 14.540)

2. No

8 (3.6) 212 (96.4) 1.00

1.00

Is your habit of frequent usage of perfume 1. Yes

7 (19.4)

29 (80.6) 3.756 (1.503, 9.381) 2.180 (0.724, 6.570)

2. No

25 (7.2) 279 (91.8) 1.00

1.00

Presence of vermin/dust in the home 1. Yes

26 (13.6)

165 (86.4) 2.694 (1.072, 6.768) 2.999 (1.106, 8.129)

2. No

6 (4.0) 143 (96.0) 1.00

1.00

Discussion

In this study the prevalence of Bronchial asthma was 9.4% (95%CI: 6.5, 12.9). This finding is comparable with study conducted in the Kingdom of Saudi Arabia in 2001; the prevalence of asthma was 12 % [19]. This also in line with study done in Africa estimated that a prevalence of 11.7% for asthma, totaling over 74 million people in 1990, and 2010 prevalence was 12.8%, about 120 million people (4). This also in line with study done In Africa the prevalence of asthma was estimated 9.6% in Swaziland, 7.8 in Comoros, 7.54% in Mauritania and in range of 0-10% in Ethiopia [21]. This may be due to similarity of study design and sample size.

This finding is higher than study done in Portugal on Prevalence of asthma which states that the prevalence of diagnosed asthma was 5.0%. This finding is higher than another study done in Addis Ababa which was the prevalence of asthma and factors that lead patients to visit adult emergency room of Zewditu Memorial Hospital, Ethiopia was revealed that the prevalence of bronchial asthma was 1.5% [14].

This finding is lower than study done in Malaysia, 73% out-patient clinic attendants are treated for respiratory symptoms and asthma is one and major cases. It is estimated that there is 1.6 to 2 million asthmatics in Malaysia [20]. This finding is lower than another study done in Addis Ababa which was the prevalence of asthma and factors that lead patients to visit adult emergency room of Zewditu Memorial Hospital, Ethiopia was revealed that the prevalence of bronchial asthma was 1.5% [14]. This finding is also lower than another studies mentioned that (cumulative prevalence of asthma) was highest in South Africa (53%, 5-12 years) in 1997,followed by Egypt (26.5%, 11-15 years) in 2005, Nigeria (18.4%, 15-35 years) in 1995, and Ethiopia(16.3%, >20 years) in 1997.

This study revealed that urban residents were 3.425times [AOR=3.425; 95%CI: (1.036, 11.319)] more likely to develop bronchial asthma than rural residents. It was consistent with the report in Brazil and Ethiopia [15,16]. This might be explained outdoor air of urban area is highly polluted due to high levels of traffic and industry related emissions that could increase the risk of asthma. In contrast, study done in India [17] showed that being a rural resident was significantly higher the odds of having asthma. Research conducted in Ethiopia [18] revealed that no association between asthma and residence of the patients. These variations might be due to the difference in the characteristics of the study population, geographical distribution and case definitions used to ascertain asthma.

Patients having sinusitis were 4.546 times [AOR=2.971; 95%CI: (1.193, 7.397)] more like to encounter bronchial asthma compared to those who have not yet faced this co-morbid. This might be due to the fact that large number of the study subjects live in urban area and in this place there are many chemicals, gases and the like that will worsen the sinusitis status then end up with acute attack. Both seasonal and viral chronic sinusitis are among the most common triggers of acute severe exacerbations and may invade epithelial cells of the lower as well as the upper airways and there is an increase in airway inflammation with increased numbers of eosinophil and neutrophils along with nasal congestion as well as airway tract edema in addition to increment in airway hyper-responsiveness [19,20].

This study indicated that patients who come from the family history of asthma were 5.796 times [AOR=5.796; 95%CI: (2.311, 14.540)] more likely to develop bronchial asthma than from non-asthmatic family. Similar findings have been reported by other studies in developed and developing countries that showed a significant association between family history of asthma and asthma occurrence among adult patients [20,21]. This association could be either due to genetic factors or a shared environment by the family members.

In this study, present of vermin at household level were 2.999 times [AOR=2.999; 95%CI: (1.106, 8.129)] increased the probability of developing bronchial asthma among adult patients. The world health organization report in 2008 report also showed that evidence for a relationship between asthma and domestic exposure to cockroaches, mice and dust mites is strong. This could be explained by house which have vermin’s concerns with the use of insecticides prays at home, with more frequent use being associated with bronchial asthma. Similar results can be found in the literature regarding the link between the use of home aerosolized cleaning products and asthma.

Conclusion

This finding the prevalence of Bronchial asthma was 9.4% (95%CI: 6.5, 12.9). However, Bronchial asthma was significantly associated Type of Residence, Wheezing, Cough, and Rhinitis, Family history of asthma and Presence of vermin/dust in the home was identified as the most important risk factor for Bronchial asthma.

Recommendation

Based on the findings of the study the following recommendations could be mentioned

For Health Professionals

  • Health care providers should work on improving patients’ awareness on their medications adherence, avoidance of asthma triggering factors for decreasing the progression of the disease and better asthma controls.

For the Hospital

  • Staffs should teach about asthma triggering factors.

References

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  8. Sharma S, Sood M, Sood AJCPR (2011) Environmental risk factors in relation to childhood asthma in rural area 15(1): 29-32.
  9. Elfaki N, Shiby AJJCRDC (2017) Risk factors associated with asthma among Saudi adults in Najran 3(133): 2472-1247.1000133.
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  11. Asthma GIf. 2018 GINA report, global strategy for asthma management and prevention.
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  13. Mulat T (2015) Assesment of Prevalence and Pattern of Medication Prescription for Bronchial Asthma, at Adult Emergency Department of Tikur Anbesa Specialsed Hospital. Addis Ababa University.
  14. Fentahun S (2017) A Study on the Assessement of Prevalance of Asthma and Factors that Lead Patients to Visit Adult Emergency Room Of Zewditu Memmorial Hospital, Addis Ababa. Addis Ababa University.
  15. Aït-Khaled N, Enarson D, Bousquet JJBotWHO (2001) Chronic respiratory diseases in developing countries: the burden and strategies for prevention and management 79: 971-9. [crossref]
  16. Hamdan Al-Jahdali AAJB, PUL. MED (2012) Salim bathrooms, factors associated with patients visit to the emergency department for asthma therapy 12: 80. [crossref]
  17. Amoah AS, Forson AG, Boakye DAJGMJ (2012) A review of epidemiological studies of asthma in Ghana 46(2): 23-8. [crossref]
  18. Sa-Sousa A, Morais-Almeida M, Azevedo LF, Carvalho R, Jacinto T, Todo-Bom A, et al. (2012) Prevalence of asthma in Portugal-The Portuguese National Asthma Survey 2(1): 15. [crossref]
  19. Al-Mazam A, Mohamed AGJJof medicine c (2001) Risk factors of bronchial asthma in Bahrah, Saudi Arabia 8(1): 33. [crossref]
  20. Ngui R, Lim YAL, Chow S, de Bruyne J, Liam CJMJoM (2011) Prevalence of bronchial asthma among Orang Asli in Peninsular Malaysia 66(1): 27-31. [crossref]
  21. Barry A, Caesar J, Klein Tank A, Aguilar E, McSweeney C, Cyrille AM, et al. (2018) West Africa climate extremes and climate change indices 38: e921-e38. [crossref]
fig 1

A Reappraisal of the Foundations of the Special Relativity Theory

DOI: 10.31038/NAMS.2022522

Introduction

The first purpose of the present paper is to clarify the scientific approach Einstein [1] adopted when he developed the Specia Relativity Theory (→SRT). This can be done when we compare his approach with two long-established and characteristically different methods in use to gain relevant scientific knowledge: the phenomenological and the axiomatic method.

The second aim of this paper will then be to analyse from an immanent-logical point of view:

(i)  Einstein’s postulates of the SRT and their implications;

(ii) How Einstein – starting from the postulates he had introduced – attempted to derivate the Lorentz [2] Transformations.

Said in other terms: I shall concentrate my attention on the inner consistency of the SRT.

Two Classical Methods for Scientific Knowledge

The Phenomenological Approach

(i)  We often start our observations and investigations with appearances of sensory modality. Consider, for instance, the following experiences (1. – 6.): 1. We look at the sun, the moon, the planets, and unexpectedly begin to wonder about their respective movements; 2. We perceive several flowers, and suddenly set on to wonder what traits they may have in common and wherein they could differ from each other – and this sets in motion a closer look at them and a comparison of their striking structures; 3. We gaze at several birds, and suddenly find ourselves engaged in observing and comparing their behaviour; 4. We look at tides and sea currents and begin to wonder about the rhythms they are involved in; 5. We investigate the phenomena of electromagnetic induction – and go over to arrange an experimental setting, varying it in the course of our observations, etc.

(ii)  Many of the investigations hinted at set off from “open” intentions, which we specify when intending to clarify the relations implicit in the phenomena that puzzle us.

(iii)  We are thus led to the formulation of rules, tendencies, laws; we become aware of certain probabilities – and are thereby encouraged to modify our primordial intention, to ask new questions, to foster new investigations, always endeavouring to remain close to the phenomena, saving the appearances.

The Axiomatic Approach

First systematically presented by Euclid [3,4] in his Elements of Geometry, further developed and specified by logicians and mathematicians (e.g. B. Pascal [5], G. Frege [6-8], P. Finsler [9]) in the course of 2000 years, the characteristic features of an axiomatic approach can be summarized as follows:

(i)  If we aim to open a field of knowledge according to the axiomatic method, we start from a cognitive intention which we specify step by step, formulating clear postulates. We thereby establish what kind of mental processes we intend to be engaged in.

(ii)  We will then set forth to introduce certain words, signs, terms, defining unambiguously what these expressions shall henceforth mean and refer to within the context at issue.

(iii)  Constitutive to the axiomatic method is the fact that if we steadily hold to the postulates we are led to elementary, fundamental insights, i.e. axioms. Epistemologically speaking, the axioms follow necessarily from the postulates. They are basic insights which cannot be reduced to yet more fundamental assertions. We can therefore look upon the axioms as being self-evident.

(iv)  Starting from the axioms, we can derive higher structured propositions, i.e. theorems, by means of logical reasoning. This holds true, even if many a researcher may catch sight of the content of a theorem, before realizing that the theorem in question can be logically traced back to the axioms.

(v)  If we develop an axiomatic system, we implicitly acknowledge that the Principles of Logic are unrestrictedly valid – at all levels of our investigation. The two main principles I’ll be concerned with in the present paper are: a) The Principle of Identity, requiring that every term we have introduced maintain its univocal meaning throughout the entire investigation; b) The Principle of Non-Contradiction, demanding that neither postulates nor axioms (and, consequently, theorems) contradict one another.

(vi)  Accordingly, in fields of knowledge opened and determined by the axiomatic method (e.g. in pure mathematics), a mental item (a “thing”) exists, and an assertion is true if the former and the latter are exempt from contradictions.

A Short Comparison of the Two Approaches to Scientific Knowledge Reveals

(i)  A scientist working phenomenologically does not a priori question the reality of the objects and appearances he deals with in his investigations; he simply tries to unveil the rules and correlations hidden in them.

(ii)  A mathematician embracing the axiomatic method formulates postulates of exclusively mental content, advancing to axioms and theorems. The existence of the objects he is concerned with, as well as the truth of his findings, depends entirely on the non-contradiction of the postulates – and this includes the axioms and the theorems that correspond to the postulates. A mathematician has the right to declare that certain signs, ciphers, symbols, drawn figures represent the mental objects he conceives and deals with, but the signs and symbols lack value of their own – they rather are a mnemonic that helps us to pursue the line of thought expressed in the postulates and axioms of purely mental content.

(iii)  Although the phenomenological and the axiomatic approaches differ from one another, each one of them is clearly determined, and both are – in principle – free from contradictions.

Dogmatic-deducible Approaches to Scientific Cognition

A third, completely different approach to achieve scientific cognition is practised by researchers who, imitating mathematicians, introduce postulates, but extend their enunciations to include elements which essentially belong to the modalities of the world of sensory perceptions. In other words: their postulates are not restricted to purely mental categories which – as a mere aid for grasping their content – can be illustrated by diagrams, figures, symbols; on the contrary, the postulates we are now talking about – which, as I said, include elements belonging to the world of sensory perceptions – prescribe how these latter elements must appear and evolve according to the postulates. These do not hint at tentative models, meant to explain certain phenomena – they are strict, rigid prescriptions of the sensory modalities to be expected under clearly defined settings.

I call such an approach a dogmatic-deducible theory. A good example of such theory (or approach) is Einstein’s introduction to his Special Relativity Theory (=SRT) in the papers of 1905 and 1922/56.

The Special Relativity Theory (SRT) – A Dogmatic-Deducible Theory

Einstein based his SRT on two explicit postulates:

Postulate 1: The Postulate of Relativity (=PoR), demanding that in two inertial frames of reference K° and K’, moving reciprocally at a constant speed v along their parallel x°- and x’-axes, identical laws of Nature are valid;

Postulate 2: The Postulate of Constant Speed of Light (=PoL), originally introduced by declaring that for observers firmly placed along the x°-axis of K°, a flash of light L°, emitted by a source of light Q° of K° in the positive direction of the x°-axis, will always be propagated and arrive at an equal speed c, independently of any motion of Q° along the x°-axis at the time it emits L°.

I shall call this arrangement: Configuration I.

I have formulated both postulates of the SRT in a clear, unambiguous way – in complete accord with the formulations advanced by Einstein in his papers of 1905 and 1922/56.

The postulates reveal that each one of them contains several elements that do not belong to the realm of the purely mental concepts of mathematics and logic:

(i)  In Postulate 1, the PoR, we find “frames of reference that are moving reciprocally at a constant speed v”; and also “laws of Nature”;

(ii)  In Postulate 2, the PoL, we have “a flash of light will always be propagated and arrive at an equal speed c, independently of any motion of Q° along the x°-axis at the time it emits L° “.

Such terms as ‘speed’, ‘motion’, ‘flash’, ‘Laws of Nature’ form an essential part of what is demanded in the Einsteinian Postulates. These postulates demand and determine how certain elements of sensory perceptive modality must appear and have to evolve within the system presented and specified by the PoR and the PoL. They strictly prescribe what an observer in K° and K’ must observe and measure.

Let us now look at Configuration I, as introduced by Einstein: (Figure 1).

fig 1

Figure 1: K°, K’: frames of reference (inertial systems); v: relative speed of K’ with respect to K°; Q°: source of light, placed at the zero point of the coordinates of K°, which emits the flash of light L° in the positive direction of the x°-axis. The figure represents Configuration I.

Let us now change to Configuration II: (Figure 2).

fig 2

Figure 2: K’, K°: frames of reference (inertial systems); v: relative speed of K° with respect to K’; Q’: source of light, placed at the zero point of the coordinates of K’, which emits the flash of light L’ in the positive direction of the x’-axis. The figure represents Configuration II.

If we compare Configuration II with Configuration I, we see that the two configurations are completely symmetrical. One of the most important points to consider is, that the PoR has been applied correctly: The source of light Q°, placed at the zero point of the coordinates of K° in Configuration I, has been replaced by the source of light Q’, correctly situated at the zero point of the coordinates of K’. And, of course, whereas in Configuration I it was stipulated, that the flash of light L° would move with velocity c with respect to observers firmly placed on the positive x°-axis of K°, independently of any motion of Q° in relation to these observers of K° – we now see that in Configuration II we have established completely symmetric conditions, resulting in an enunciation that proclaims that the flash of light L’, emitted by Q’ in the positive direction of the x’-axis will move with the same velocity c with respect to observers of K’ that are firmly located on the x’-axis, independently of any motion of Q’ at the time it emits L’. If we transform Configuration I into Configuration II taking care to install completely symmetric conditions, the result is totally free from contradictions.

Einstein’s Logic Fallacies in His Papers of 1905 and 1922/56:

The Lack of Symmetric Conditions

Einstein wrote that the flash of light L° in K° in Configuration I moves with constant speed c for all observers firmly placed in K° and would “… in connection with the Principle of Relativity [i.e. PoR] also [propagate] with velocity V [i.e. c] when measured in the moving system [i.e. K’]”… In other words: also move with the same speed c for observers firmly placed on the x’-axis of K’. In short: Einstein argued that the same light-signal L°, emitted by the source of light Q° of K° and moving at speed c for observers at rest in K°, would also propagate itself for observers at rest in K’ at equal speed c, notwithstanding the premise that the systems K° and K’ were moving in relation to each other at the constant speed v. Einstein erroneously applied the PoR together with the PoL directly to the flash of light L°, without transferring the source of light from K° to K’. He didn’t arrange for K’ a configuration symmetric to the one he had established for K°. This lack of symmetry between K° and K’ definitely rules out any application of the PoR. By neglecting to introduce strictly symmetric configurations in K’ to those in K°, Einstein violated the Principle of Non-Contradiction – since K’ is, in his case, no longer equivalent to K°, although he had begun with the premise that the conditions were to be equivalent.

The Mutual Relative Speed of K° and K’

Besides the lack of symmetry, there is yet another point worth looking at: Einstein established as a premise that the mutual relative speed of K° and K’ is to be v ≠ 0, when measured by observers in K°, and also when measured by observers in K’. This implies that exactly the same units of measurement are to be valid in K° and in K’. By strictly holding to this premise, it follows that the flash of light L°, emitted by Q° in K° cannot move at same speed c for observers at rest in K’ as for observers at rest in K°. If the mutual relative velocity between K° and K’ remains v ≠ 0 – with the same value, when determined by observers in K’ and in K°-, the flash of light L° can only move artificially with the same numerical value c for observers in K’ as in K°, if we deliberately change the units of measurement in K’ in a way that the same numerical value issues. But by acting in such a way and implicitly – and tacitly – maintaining the very same symbols ‘m’ for meters and ‘s’ for seconds in K’, as well as in K°, we convey different meanings to these symbols in K’ with respect to the meaning they have in K°- and this is an obvious transgression of the Principle of Identity.

Conclusion

Einstein’s 1905 and 1922/56 papers on the introduction of his Special Relativity Theory are logically inconsistent. Einstein misapplied the Postulate of Relativity, since he neglected to establish symmetric conditions in the equivalent frames of reference K° an K’ he had introduced at the outset of his papers. Furthermore, Einstein transgressed the Principle of Identity, since he maintained the same symbols for length and time throughout his papers, but changed their meaning, i.e. what they referred to at the beginning. Finally, Einstein maintained that the same units of measurement were to be valid in both systems K° and K’ as far as the determination of their mutual relative velocity was concerned, but untenably changed the units with regard to the determination of the speed of a light-flash in the two systems he considered. It follows that Einstein’s Special Relativity Theory is inconsistent. It violates the Principle of Identity and the Principle of Non-Contradiction. As such, the SRT cannot be corroborated experimentally. Experimental findings have to be interpreted on a consistent line of thought.

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