Open Science Journal (OSJ)
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Thermoelectric generators
Get PDFAs the world is changing and developing with every passing day, the requirements of power are also increasing. There is a shift in utilizing the electrical energy as much as possible and for this reason, many countries have already made policies for completely ruling out the machines which don’t run on electricity. Apart from electricity, there are other forms of energy that can be used to convert that form into a more desirable form. For example, in a plant where the smoke comes out of the chimneys or in a car, the smoke carries a large amount of thermal energy with it. This energy is nothing but a waste and reduction in the efficiency of the systems. If somehow, this energy could be recovered, the efficiency can be increased. Thermoelectric generators serve for this purpose. Thermos electric generators get the heat and using the principle of heat conduction and p and n type materials, the heat can be directly converted into the electricity. There are many materials available in the market for p and n type but in our case, we chose silicon germanium which is also one of the most commonly used. First of all, a single module of thermoelectric generator will be made using p and n type material, as well as using conductive material and some ceramic substance. Then, the entire assembly will be made and this assembly will be exported to Ansys where custom materials will be added and applied on to the geometry. After performing analysis on full model, a comparative study will be presented in which the effect of material of conductive plate on to the voltage difference will be studie
Challenges in doctoral supervision in South African universities
Get PDFThis article addresses the challenges encountered by doctoral supervisors as they interact with their doctoral students in the contexts of South African universities. In a qualitative study of seven doctoral (PhD) supervisors and six PhD students, data was collected using interviews to examine the challenges supervisors experience as they supervise doctoral students. The PhD students were included in this study in because their responses would confirm or refute supervisor's views/opinions that emanated from their experiences in a social, cultural, and political context. Data analysis showed that doctoral supervisors experienced multiple challenges including overworking, time, and a set of academic characteristics of PhD students. Overall, the results of this study suggest that certain aspects among doctoral students who have completed doctorates in South African context, and their supervisors in different parts of the world would provide a starting point in the understanding of the implications of these aspects and their effect on the selection of doctoral students and the ongoing research in doctoral supervision in the South African context. doctoral supervision
The offer of corporate social responsibility and business ethics courses in university accounting undergraduate programs: A comparative analysis among administrative sciences
Get PDFBusiness failures in the 1980s, in the United States, have prompted the undergraduate programs of Business Administration, Public Administration, Foreign Trade, Accounting and Auditing, Economics, Finance, Management and Leadership, Human Talent Management, Transportation Management, Business Management, Marketing, International Business and Tourism to strengthen the techniques and processes of education of the future professionals, based on the teaching of social responsibility and ethics. Hence, the main purpose of this research is to analyze the presence of subjects related to Business Ethics and Corporate Social Responsibility (CSR) at Universities and Polytechnic Schools that are within the National Public and Private classification, and which receive allocations and revenues from the State in Ecuador. For this purpose, null hypotheses (Ho) and alternative hypotheses (H1) have been proposed, obtaining significant statistical evidence in the analysis of 89 curricula of administrative science programs. The analysis shows that the offer of the 47 studied subjects of social responsibility, and 75 of ethics does not depend on whether the university is public or private to receive allocations and revenues from the State, but it does depend on the type of program or degree that is being offered. These higher education subjects are important to help, the future professional, remember his or her correct behavior, commitment, and actions in the company, in society, and in the environment
The protective effects of adenosine deaminase inhibitor and ouercetin against hepatocellular carcinoma induced by thioacetamide in male rats via downregulation of iNOS, Ki67 and Pan-CK
Get PDFThe liver is the largest and most vulnerable organ in the body, several factors can cause liver cirrhosis and the onset of hepatocellular carcinoma. This study aims to investigate the possibility for adenosine deaminase inhibitor (EHNA) which reduces liver injury, neutrophil infiltration and the levels of proinflammatory cytokines and also it is considering as a target of liver cirrhosis and beginning of hepatocellular carcinoma protective, quercetin which is one of the most common flavonoids has an antioxidant, antitumor and chemopreventive effect on the liver-induced preneoplastic lesions and their combination against thioacetamide as a hepatotoxic and a carcinogenic compound. Biochemical, histopathological and immunohistochemical studies were carried out on male albino rats model to evaluate this possibility. Thioacetamide-treated rats showed a significant increase in liver function tests, alpha-fetoprotein level, expression of inducible Nitric Oxide Synthesis (iNOS), Ki67 and Pan-Cytokeratin (Pan-CK) in hepatic tissue of rats. The results of the present study show that treatment with quercetin, EHNA or their combination attenuated changes in liver functions, histopathological changes, reduced collagen deposition and decreased the expression of iNOS, Ki67 and Pan-CK induced by thioacetamide
Social perceptions influencing the fight against Covid-19 in Cote D’Ivoire
Get PDFIn a context of new outbreak of the Covid-19 after a phase of control, the problem of influence of perceptions of professional and community actors on the epidemiological riposte arises in Africa and particularly in Côte d'Ivoire. Indeed, the main question is how could strengthening community involvement contribute to resilience against Covid-19 in Côte d'Ivoire? The study is based on a mixed method that combines quantitative and qualitative approaches. Quantitatively, it involves exploiting the daily statistics on Covid-19 in Côte d'Ivoire. The qualitative aspect requires the analysis of official, administrative, audio-visual and iconographic documents supplemented by investigations within a collective intelligence network and among a population of men and women in bus stations, markets and supermarkets in Cocody, Yopougon and Abobo in the city of Abidjan. 166 people were interviewed.The results show that an organizational framework for the epidemiological riposte exists in Côte d'Ivoire with the multi-sector riposte plan as its anchor. Statistics related to this struggle show that after six months, more and more recoveries occur as new cases are confirmed. Likewise, active cases and deaths have a downward trend. Despite an acceptable score, some populations perceive the organization of the fight as centralized, infiltrating initiatives at the operational level by excluding community health workers; and others perceive it as a finding for those in power to benefit from Covid funds from the international community. All of these perceptions have a negative influence on the conduct of the epidemiological riposte and community involvement. This is characterized by the slackening of the involvement of certain professional and social actors in the fight, the non-respect of hygienic and social distancing measures, as well as difficulty in determining the originality of national resilience
Estimating sex by analyzing linear measurements of Brazilians’s dry skulls
Get PDFBrazilian forensic physical anthropology has developed substantially in recent years, thus, new regression models are being obtained and models proposed by international researchers are being validated, both in a national sample. This search is greatly significant for national forensic anthropology, due to our unique ancestral constitution, allowing for a gain in efficiency and reliability in the process of human identification. We sought to evaluate 12 linear measures, aiming to verify the existence of sexual dimorphism, as well as the possibility of developing a regression model to estimate sex. The researcher was properly trained and calibrated (ICC=0.95). After this stage, the data measured in 186 skulls (105 males and 81 females, with ages ranging from 18 to 80 years old, were analyzed. To perform the linear measurements, straight and curved digital calipers, duly calibrated, were used. According to the statistical analysis, all measurements performed are dimorphic. It was possible to build a logistic regression model for sex estimation. Notably, a sensitivity of 81.7% and specificity of 79.2% were found, with an accuracy of 80.65%. It was found that the logistic regression model obtained can be used as an auxiliary method in estimating sex in Brazilians
How do complex phenotypes evolve? Solving the “gene for X” problem with atavisms, homeosis, and other evo-devo surprises
Get PDFHelping students learn how major phenotypic shifts evolve is a major hurdle for biology educators. Fortuitously, teachers can exploit the oft-misunderstood “gene for X” concept to explain how evolution, and complex phenotypes, often turn on single changes to regulatory genes governing expression of structural genes during development. This explains how one gene can make a big difference, and relates microevolution relates to macroevolution, a frequent hang-up for evolution deniers. Although complex traits such as intelligence do not derive from a single gene, minor tweaks in gene regulators produce atavisms (sudden appearance of “throwback” features), homeotic mutants (whose altered features stem from shifts in developmental timing and location), and other major changes in organismal morphology. Biology educators must explain how evo-devo mechanisms profoundly shift the course of evolution and drive phenotypic change. An adult form does not evolve into another, but underlying development readily evolves
Reforms of the Gabonese education system: What challenges?
Get PDFIn the field of education, the idea that an educational system can improve is not just an act of faith. Empirical research in social sciences and organizational management has shown that such improvement can only be achieved through reforms and their efficient implementation. However, studies have shown that, in a similar social context, certain approaches produce opposite effects. This article presents an overview of the reforms of the Gabonese education system from the 1960s to the present day. It has examined the main administrative acts that have framed the content of its reforms, highlighting significant advances in terms of material and social achievements. We noted that the Gabonese education system from the 1960s to the 1970s increased the schooling of young people to more than 90%. Twenty years later, the system was dysfunctional in terms of a shortage of qualified teachers, classrooms and quality of education. Added to this is the high rate of repetition and school failure. Thus, the manner in which education reforms are carried out in Gabon explains the delays noted
The role of cardiac biomarkers in early detection of cardiotoxicity in breast cancer treated with trastuzumab in the adjuvant setting: a systematic review
Get PDFTrastuzumab, a humanized monoclonal antibody against the extracellular domain of human epidermal growth factor receptor 2 (HER-2) prolongs disease-free survival (DFS) and overall survival (OS) in patients with early-stage breast cancer. Although it is generally well tolerated, it has been associated with cardiotoxicity, mainly a reduction of left-ventricular ejection fraction (LVEF), especially if the patient has received anthracyclines.It is generally known that a drop in LVEF has limited diagnostic ability. Therefore, the identification of serum biomarkers of cardiotoxicity, able to detect damage at an earlier phase, has become ideal. Troponins (conventional and high sensitive), natriuretic peptides, reactive C protein (CRP), myeloperoxidase (MPO), etc are different molecular markers which have been assessed to check their role in the detection of treatment induced cardiotoxicity (CTIC) with controversial results.OBJECTIVEThis systematic review will synthesize available evidence assessing the role of different serum biomarkers in early prediction of cardiotoxicity in breast cancer patients treated with adjuvant trastuzumab.METHODS/DESIGNSystematic review conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. Distinct scientific databases such as Google Scholar, Pubmed, EBSCOhost, and PsycINFO were searched to aid in the investigation of the research problem.Randomized clinical trials (RCT) and observational studies of patients with early breast cancer receiving adjuvant trastuzumab were eligible for inclusion. Two investigators have independently evaluated those studies and used standardized data extraction templates to collect data on the study and patients’ characteristics.RESULTS 11 articles were selected, one RCT and ten observational studies. The most studied biomarker was N-terminal-pro-brain natriuretic peptide (NT-proBNP) followed by troponins. Findings showed that NT-proBNP was not predictive of CTIC while conflictive results were seen with troponins.One study showed a predictive role of high sensitive (hs) CRP and another found a relationship with the levels of MPO.CONCLUSIONBiomarkers offer a unique potential to improve the effectiveness and safety of trastuzumab through timely detection of CTIC and prompt initiation of appropriate treatment. Troponins I and T have shown a predictive role in early detection of CTIC but further research would be needed to enable more insight and improve the overall patient outcome
Challenges and experiences faced by social workers working with children exposed to abuse and neglect
Get PDFChild abuse and neglect are the most disturbing problems in the field of child welfare. In the area of child welfare, all over the world, it is common social workers engaged with children such as psychologists; nurses and pediatrician are often affected while carrying out their respective duties. The study is intended to explore the dynamic problems such social workers experience in their line of duty. The issue of social workers engaging with children exposed to child abuse and neglect require much attention and it has to be addressed in line with the child protection system. The child protection system is one of the frameworks of the whole child welfare which provide social services to children exposed to abuse and neglect. In the field of child welfare, different social workers for example pediatricians, psychologists etc work together in assessing children in relation to abuse and neglect. Therefore, this study showcases the need for supportive practice for social workers in the field of child protection to work together. Key Words: Child protection, Social worker, Child abuse and neglect