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Analysis of Modeling the Influence of Electromagnetic Fields Radiated by Industrial Static Converters and Impacts on Operators Using Maxwell’s Equations

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Open Journal of Applied Sciences 2024年第8期14卷 2320-2350页

作者： Anthony Bassesuka Sandoka Nzao Tuka Biaba Samuel Garcia Obed Bitala Arsène Kasereka Kibwana Emmanuel Ndaye Kibuayi ISTA Kinshasa Electrical Engineering Kinshasa Democratic Republic of Congo Doctoral School of ISTA Kinshasa Complementary Master in Science and Technology/Electrical Engineering Electrotechnical Option Kinshasa Democratic Republic of Congo ISTA Kinshasa Doctoral School in Science and Technology Electronics Option Kinshasa Democratic Republic of Congo

The study of Electromagnetic Compatibility is essential to ensure the harmonious operation of electronic equipment in a shared environment. The basic principles of Electromagnetic Compatibility focus on the ability of devices to withstand electromagnetic disturbances and not produce disturbances that could affect other systems. Imperceptible in most work situations, electromagnetic fields can, beyond certain thresholds, have effects on human health. The objective of the present article is focused on the modeling analysis of the influence of geometric parameters of industrial static converters radiated electromagnetic fields using Maxwell’s equations. To do this we used the analytical formalism for calculating the electromagnetic field emitted by a filiform conductor, to model the electromagnetic radiation of this device in the spatio-temporal domain. The interactions of electromagnetic waves with human bodies are complex and depend on several factors linked to the characteristics of the incident wave. To model these interactions, we implemented the physical laws of electromagnetic wave propagation based on Maxwell’s and bio-heat equations to obtain consistent results. These obtained models allowed us to evaluate the spatial profile of induced current and temperature of biological tissue during exposure to electromagnetic waves generated by this system. The simulation 2D results obtained from computer tools show that the temperature variation and current induced by the electromagnetic field can have a very significant influence on the life of biological tissue. The paper provides a comprehensive analysis using advanced mathematical models to evaluate the influence of electromagnetic fields. The findings have direct implications for workplace safety, potentially influencing standards and regulations concerning electromagnetic exposure in industrial settings.

关键词： Modeling Electromagnetic Field Power Converters Geometric Parameters Biological Tissue Maxwell Equation Bio-Heat Equation Thermal Model

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Superficial Angiomyxoma of the Vulva: A Case Report

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Open Journal of Pathology 2024年第2期14卷 64-68页

作者： Zo Irène Raivoherivony Herilalao Elisabeth Razafindrafara Vahatra Joëlle Razafimahefa Romuald Randriamahavonjy Nantenaina Soa Randrianjafisamindrakotroka Department of Pathology Joseph Ravoahangy Andrianavalona University Hospital Antananarivo Madagascar Department of Pathology Soavinandriana University Hospital Antananarivo Madagascar Department of Pathology Andrainjato University Hospital Fianarantsoa Madagascar Gyneco-Obstetrics Department Soavinandriana University Hospital Antananarivo Madagascar

Superficial angiomyxoma is a rare benign mesenchymal tumor that mainly occurs in the genital region. We report the case of a 51-year-old woman with a painless vulvar mass, well circumscribed on ultrasound. On gross finding, it was a polypoid and bilobed mass, partially encapsulated. On histological examination, it was a proliferation of non-atypical spindle cells with an abundant, myxoid stroma and numerous medium-sized blood vessels. The diagnosis was superficial angiomyxoma. The clinical features do not often lead to the diagnosis of superficial vulvar angiomyxoma. It is based on histological examination and immunohistochemistry is helpful to differentiate it from other myxoid tumors.

关键词： Angiomyxoma Mesenchymal Tumor Myxoïd Stromal Tumor of Vulva

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Influence of Production Factors on the Physico-Chemical Characteristics of Fermented Cassava Dough and Sensory Evaluation of Attieke

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Food and Nutrition Sciences 2024年第5期15卷 361-376页

作者： Weiléko Hélène Dougba Djedjro Clément Akmel Emmanuel Aya Diane Boudouin Dibi Nogbou Emmanuel Assidjo Laboratory of Industrial Processes for Environmental Synthesis and new Energies Institut National Polytechnique F&#233lix Yamoussoukro C&#244te d&#8217Ivoire Department of Agro-Food and Food Industries UFR Agriculture Fisheries Resources and Agro-Industry University of San-Pedro San-Pedro C&#244te d&#8217Ivoire

Attieke is an Ivorian semolina which obtained by fermenting, pressing and steaming cassava dough. Attieke production remains a traditional activity carried out by less literate women. However, perceived differences in measurable factors and attieke qualities require an investigation of their influence on the characteristics of the pressed dough and attieke. The aim of this study is to improve the quality of the dough in relation to that of the attieke produced. The experiment was carried out on 4 production factors, namely the type of boiled or braised ferment, the incorporation rate of the ferment between 8 and 10%, the addition of oil from 0.1 to 1% and the fermentation time from 12 to 15 hours applied to the Improved African Cassava (IAC) variety. A complete experiment design of 16 samples of fermented dough and attieke was employed. These samples underwent physic-chemical analyses for the fermented dough and sensory evaluation for the attieke. It was found that, except for titratable acidity, reducing sugar content and ash content, the physico-chemical characteristics of the dough of IAC variety were significantly influenced by all production factors and their interaction. Fermentation time significantly influences 60% of the physico-chemical characteristics of the fermented dough. The type of ferment, the oil addition and the ferment rate have a significant influence at 40% of these characteristics. At the sensory level, color, acidity and grain binding with an explained variance of 34.60% were essential for the appreciation of the attieke samples. Thus, these production factors could be considered for the improvement of the fermented dough and attieke production process.

关键词： Influence Production Fermented Dough Attieke

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Hexavalent Chromium Cr (VI) Removal from Water by Mango Kernel Powder

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Journal of Materials Science and Chemical Engineering 2024年第1期12卷 84-103页

作者： Amadou Sarr Gning Cheikh Gaye Antoine Blaise Kama Pape Abdoulaye Diaw Diène Diégane Thiare Modou Fall Laboratoire de Chimie Physique Organique et d’Analyses Environnementales (LCPOAE) Université Cheikh Anta Diop Dakar Sénégal Equipe Chimie des Matériaux Inorganique et Organique (ECMIO) Université Alioune Diop Bambey Sénégal Equipe des Matériaux Electrochimie et Photochimie Analytiques (EMEPA) Université Alioune Diop Bambey Sénégal Laboratoire de Photochimie et d’Analyse (LPA) Université Cheikh Anta Diop Dakar Sénégal

Metal trace elements (MTE) are among the most harmful micropollutants of natural waters. Eliminating them helps improve the quality and safety of drinking water and protect human health. In this work, we used mango kernel powder (MKP) as bioadsorbent material for removal of Cr (VI) from water. Uv-visible spectroscopy was used to monitor and quantify Cr (VI) during processing using the Beer-Lambert formula. Some parameters such as pH, mango powder, mass and contact time were optimized to determine adsorption capacity and chromium removal rate. Adsorption kinetics, equilibrium, isotherms and thermodynamic parameters such as ΔG˚, ΔH˚, and ΔS˚, as well as FTIR were studied to better understand the Cr (VI) removal process by MKP. The adsorption capacity reached 94.87 mg/g, for an optimal contact time of 30 min at 298 K. The obtained results are in accordance with a pseudo-second order Freundlich adsorption isotherm model. Finally FTIR was used to monitor the evolution of absorption bands, while Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS) were used to evaluate surface properties and morphology of the adsorbent.

关键词： Adsorption Chromium Mango Kernel Powder Spectroscopy Analysis Water Treatment

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Preventive Effect of an Extract of Terminalia avicennioides on Acetylcholine-Induced Tracheoconstriction in Wistar Strain Rats

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Open Journal of Respiratory Diseases 2024年第2期14卷 60-68页

作者： Awa Ba-Diop Ndèye Absa Diaw Ibrahima Diouf Mbaye Sène Ouafae Kechaba Mamadou Sarr Modou Oumy Kane Physiology Laboratory Department of Medicine Alioune Diop University of Bambey Bambey Senegal IRL3189 Environment Health Societies CNRS-UCAD Dakar Senegal Department of Physiology Laboratory Faculty of Medicine Cheikh Anta Diop University of Dakar Dakar Senegal Department of Physiology Laboratory Faculty of Medicine UFR Sante Assane SECK University of Ziguinchor Ziguinchor Senegal

Asthma is one of the most common chronic respiratory pathologies worldwide. The cost of its treatment, particularly for populations in developing countries like Senegal, requires an alternative which consists of developing research into new therapeutic approaches with the use of plants from traditional pharmacopoeia. The objective of this study was to determine whether the hydroalcoholic extract of Terminalia avicennioides leaves has a preventive effect on the constriction of tracheal smooth muscle induced by Acetylcholine in Wistar strain rats. Methods: The species used in our experiments were male Wistar rats aged between 12 and 14 weeks. Rings of rat trachea were suspended in isolated organ chambers connected to tension sensors. Two pharmacological agents were used: acetylcholine, for its constrictor effect and adrenaline, for its dilating effect on the pulmonary trachea. Our plant material consisted of a hydroalcoholic extract of Terminalia avicennioides leaves. The experimental protocol was that of the preventive model which consisted of impregnating these rings with the extract at a defined concentration then testing its contractility in the presence of Acetylcholine which was the contractile agonist used in this study. The preventive effect of the extract was studied with an Acetylcholine contraction range on rings pre-incubated with Terminalia avicennioides extract. Results: The results showed that Acetylcholine contracts the trachea and the increase in its contractility was dependent on the dose of Ach added cumulatively (10−5 to 4 × 10−5 mol/l). The administration of the hydroalcoholic extract of Terminalia avicennioides leaves led to a modification of the contractile response to Acetylcholine. Indeed, this extract induced a significant attenuation of the contractile responses of the treated tracheal rings compared to those untreated. Conclusion: Terminalia avicennioides had a relaxing effect on tracheal smooth muscle and this effect

关键词： Bronchial Hyperreactivity Extract Hydroalcoholic of Terminalia Avicennioides Asthma

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Amniotic Band Syndrome at the Van Norman Clinic in Burundi: A Case Series

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Surgical Science 2024年第3期15卷 118-124页

作者： Alice Ndayishimiye Hélène Bukuru Déogratias Niyungeko Anne Marie Nikuze Sylvestre Bazikamwe Jean Claude Mbonicura Gilbert Ndayizeye Department of Pediatrics Kamenge University Hospital Center Bujumbura Burundi Department of Obstetrics and Gynecology Kamenge University Hospital Center Bujumbura Burundi General Surgery Department Kamenge University Hospital Center Bujumbura Burundi Orthopaedy Department Kamenge University Hospital Center Bujumbura Burundi

Amniotic band syndrome is an acquired embryo-fetopathy. It is rare and is characterized by malformations mainly affecting the limbs but also the skull, face and thoraco-abdominal axis. Its etiopathogenesis remains poorly understood. Its diagnosis is essentially clinical and is classically based on the existence of signs such as furrows, amputations and pseudosyndactyly. To show the importance of antenatal diagnosis in resource-limited countries, we report the case of two newborns, one premature at 31 weeks and the other at term, in whom amniotic band syndrome was discovered incidentally at birth. It involved an amputation of the right leg for both cases. The premature baby was born in a context of neonatal sepsis and will succumb to the latter while the 2nd case was released from the hospital alive. Imaging examinations to search for probable congenital malformations could only be carried out for the 2nd case and no accessible congenital malformation had been identified. And as management of the disease, only psychological support to the parents was provided for the 2 cases. The antenatal discovery of a case of amniotic band syndrome in countries with low technical capacity such as Burundi should push clinicians to think in time about treatment options.

关键词： Amniotic Band Syndrome Embryo-Fetopathies Antenatal Diagnosis Limbs

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Physical Transformations on Organic Product during Its Convective Drying: Case of Sweet Potato

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Journal of Biophysical Chemistry 2024年第2期15卷 25-34页

作者： Ouoba Kondia Honoré Ganamé Abdou-Salam Compaoré Aboubakar Ibrango Abdoul Salam Bama Désiré Zougmoré Francois Desmorieux Hélène Laboratoire de Matriaux de lHliophysique et Environnement (La.M.H.E.) Unit de Formation et de Recherche en Sciences Exactes et Appliques (UFR/SEA) Universit Nazi BONI Bobo Dioulasso Burkina Faso Laboratoire des Matriaux et Environnement (LA.M.E.) Unit de Formation et de Recherche en Sciences Exactes et Applique (UFR/SEA) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire de Physique et de Chimie de lEnvironnement (LPCE) Ecole Doctorale Sciences et Technologie (ED-ST) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire dAutomatique et de Gnie des Procds(LAGEP) Universit Claude Bernard Lyon France

This study highlighted the physical transformation that agri-food products undergo during their drying. This transformation enormously affects the customer’s choice and the profit margin of the dried product promoter. The example of the experimental study of the potato reveals that the product continually changes its dimensions during its drying. The more the product loses its water, the more the dimensions decrease. The results initially showed that the water parameters such as mass or water content decrease according to the drying principle. The dimensions length L., width l and thickness e. decrease following a linear trend whose mathematical equations which describe them are determined using the office tool, excel. This trend has repercussions on the surface and volume parameters which in turn decreases almost linearly with the product’s water content. Note that the coefficient R2 is not always acceptable, confirming the complex nature of the behavior of organic products.

关键词： Dimensions Reduction Shrinkage Index I

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Risk Factors for Cardiovascular Disease among Hotel Workers, Bohicon, Benin

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Occupational Diseases and Environmental Medicine 2024年第2期12卷 130-141页

作者： Mênonli Adjobimey Rose Mikponhoué Eméline Gbaguidi Esdras Hountohotegbè Hélène Sacca Paul Ayélo Vikkey Antoine Hinson Unité de Recherche et d&#8217Enseignement en Sant&#233 au Travail et Environnement FSS Cotonou Cotonou Benin Service de Santé au Travail du Centre National Hospitalier Universitaire de Pneumo Phtisiologie de Cotonou Cotonou Benin Laboratoire d’ Epid&#233miologie des Maladies Chroniques et Neurologiques FSS Cotonou Benin

Introduction: Non-communicable diseases (NCDs) are on the increase in several sectors of activity. The aim of the study was to determine the frequencies of cardiovascular risk factors (CVRF) and factors associated with hypertension among hotel workers in the city of Bohicon. Methods: This was a descriptive and analytical cross-sectional study conducted in the period from December 2018 to January 2019. The variables studied were sociodemographic, occupational, anthropometric and behavioral. Participant recruitment was exhaustive. A standardized questionnaire inspired by the STEPS-WHO questionnaire was used for data collection. After the descriptive analysis, a bivariate analysis was performed using Pearson’s Chi-square test or Fisher’s test at the 5% threshold. Results: A total of 101 workers, 53 (52.47%) of them male, participated in the study. The mean age was 30.60 ± 8.20 years, with extremes of 18 and 55 years. The frequencies of the main risk factors were: 68.32% sitting position > 6 hours/day;38.61% shift work;21.78% high psychological demand, 82.18% low decision latitude, 24.75% low social support, 21.78% occupational stress;7 (6.93%) harmful alcohol consumption;6.93% tobacco consumption;48.51% insufficient physical activity;98.02% insufficient fruit and vegetable consumption;59.41% overweight;14.85% HTA. Factors associated with hypertension were: sex, age and marital status. Conclusion: Occupational factors need to be taken into account when assessing CVRFs. NCD control programs are needed in all sectors of activity. A larger study is needed in the hotel sector.

关键词： FDRCV Occupational Factors Hypertension Hotels Benin

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Bithalamic Ischemic Stroke in Sickle Cell Patient at the Kamenge University Hospital in Burundi: Case Report

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Open Journal of Medical Imaging 2024年第2期14卷 72-78页

作者： Sébastien Manirakiza Daniel Nduwayo Patrice Barasukana Chantal Murekatete Jean Bosco Bizimana Alice Ndayishimiye Léopold Nzisabira Hélène Bukuru Department of Radiology Kamenge University Hospital Center University of Burundi Bujumbura Burundi Department of Internal Medicine Neurology Kamenge University Hospital Center University of Burundi Bujumbura Burundi Department of Surgery Neurosurgery Kamenge University Hospital Center University of Burundi Bujumbura Burundi Department of Pediatrics Kamenge University Hospital Center University of Burundi Bujumbura Burundi

Aim: To describe the clinical and radiological diagnostic for a sickle cell patient who got a bithalamic vasculature accident. Observation: This was a 4-year-old female child admitted to the pediatric ward for convulsive seizures in a feverish context. The physical examination did not find signs of meningeal irritation. The effective workup including thick gout, lumbar puncture, complete blood count, and C reactive protein was normal. An electrocencephalogram was not performed due to lack of availability of the device. Based on clinical data and the fact that Burundi is an area of high malaria prevalence, antimalarial and anticonvulsant treatment has been started. An alteration of consciousness (the Glasgow score of 7) had motivated a CT scan. Bithalamic hypodensities in favor of a vascular accident have been demonstrated. Etiological investigation revealed homozygous sickle cell disease ss during hemoglobin electrophoresis. The final evolution has been characterized by a return to normal consciousness. Conclusion: The complexity of the clinical picture following occlusion of Percherons artery makes it difficult to diagnose. Sickle cell disease may favour the occurrence of ischaemic lesions. Cerebral imaging enables the diagnosis to be made with certainty and avoids delays in treatment.

关键词： Stroke Bithalamic Infarction Sickel Cell Percheron Artery

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Epidemiological, Clinical, and Evolutionary Profile of Children Admitted to the Pediatric Emergency Department of the Maroua Regional Hospital, Cameroon

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Open Journal of Pediatrics 2024年第5期14卷 878-888页

作者： Soureya Haman Kamo Selangaï Héléne Enyama Dominique Abouame Palma Haoua Salihou Sadjo Mekone Nkwele Isabelle Nguefack Félicitée Faculty of Medicine and Biomedical Sciences University of Garoua Garoua Cameroon Garoua General Hospital Garoua Cameroon Faculty of Medicine and Pharmaceutical Sciences University of Dschang Dschang Cameroon Faculty of Medicine and Biomedical Sciences University of Yaound Yaound Cameroon

Introduction: Pediatric emergencies in developing countries are associated with high morbidity and mortality. The Maroua Regional Hospital (MRH) is one of the referral centers for pediatric emergencies in the Far north region of Cameroon. Pediatric emergencies are frequent in Maroua and are associated with significant mortality. The aim of our study is to determine the epidemiological, clinical, and evolutionary profile of children admitted to the pediatric emergency department of the HRM. Methods: We conducted an observational, descriptive, and retrospective study over a period from April 10, 2023 to April 10, 2024, focusing on the records of patients admitted to the pediatric emergency department of the MRH. The variables studied included epidemiological, clinical, and evolutionary characteristics. Data analysis was performed using CSPro version 8.01 and SPSS version 27.0. Results: We included 1027 patients;the sex ratio was 1.2 infants under 2 years represented 54.33%. The main reasons for consultation were fever (62.22%) and seizures (30.18%). The most frequently prescribed additional test was the Complete Blood Count (CBC), performed in 97.37% of cases. The most common pathologies were severe malaria (45.18%), broncho-pulmonary infections (15.48%), and bacterial meningitis (12.26%). At admission, 32.9% were transfused. There were 68 deaths, representing 6.67%, and 86% of the deaths occurred within 24 hours of admission. The leading cause of death was severe malaria, with 28 (41.17%) cases. Conclusion: Febrile illnesses were the main reason for consultation, and mortality was linked to severe malaria. Therefore, in addition to the other preventive methods already used against malaria, it is recommended to consider the use of the malaria vaccine.

关键词： Pediatric Emergencies Malaria Cameroon

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