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Journal of Electromagnetic Analysis and Applications 2014年第10期6卷 309-318页

作者： Serigne Bira gueye Kharouna talla Cheikh Mbow Département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar-Fann Sénégal

An innovative, extremely fast and accurate method is presented for Neumann-Dirichlet and Dirichlet-Neumann boundary problems for the Poisson equation, and the diffusion and wave equation in quasi-stationary regime;using the finite difference method, in one dimensional case. Two novels matrices are determined allowing a direct and exact formulation of the solution of the Poisson equation. Verification is also done considering an interesting potential problem and the sensibility is determined. This new method has an algorithm complexity of O(N), its truncation error goes like O(h2), and it is more precise and faster than the Thomas algorithm.

关键词： 1D Poisson Equation Finite Difference Method Neumann-Dirichlet Dirichlet-Neumann Boundary Problem Tridiagonal Matrix Inversion Thomas Algorithm

Generalization of the Exact Solution of 1D Poisson Equation with Robin Boundary Conditions, Using the Finite Difference Method

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Journal of Electromagnetic Analysis and Applications 2014年第12期6卷 372-381页

作者： Serigne Bira gueye Kharouna talla Cheikh Mbow Département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar-Fann Sénégal

A new and innovative method for solving the 1D Poisson Equation is presented, using the finite differences method, with Robin Boundary conditions. The exact formula of the inverse of the discretization matrix is determined. This is the first time that this famous matrix is inverted explicitly, without using the right hand side. Thus, the solution is determined in a direct, very accurate (O(h2)), and very fast (O(N)) manner. This new approach treats all cases of boundary conditions: Dirichlet, Neumann, and mixed. Therefore, it can serve as a reference for solving the Poisson equation in one dimension.

关键词： Robin Boundary Poisson Equation Matrix Inversion

Asymptomatic Mitral Regurgitation Caused by an Isolated Mitral Leaflet Cleft in a Young Adult: A Case Report

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World Journal of Cardiovascular Diseases 2022年第2期12卷 118-122页

作者： Mohamed Leye Serigne Mor Beye momar Dioum Sarah Mouna Coly Désiré Alain Affangla Djibril Marie Ba Fatou Aw Khadidiatou gueye Stéphanie Akani Mouhamadou Bamba Ndiaye Training and Research in Health Sciences Unit University of Thies Thies Senegal Training and Research in Health Sciences Unit University of Saint-Louis Saint Louis Senegal Faculty of Medicine University of Dakar Dakar Senegal

We report the case of an 18-year-old young man without previous medical history, who was referred for evaluation of an asymptomatic cardiac murmur. Physical examination found holosystolic 4-5/6 apical murmur with normal ECG. Bidimensionnal (2D) echocardiography revealed severe mitral regurgitation with thin mitral leaflets. Three dimensional (3D) Echocardiography done for better assessment of mitral valve regurgitation mechanism revealed an isolated mitral leaflet cleft, without signs of endocarditis or traumatic lesion. Regarding the absence of symptoms and excellent maximal exercise tolerance at stress echocardiography, a repair surgery wasn’t offered. Isolated mitral leaflet cleft is a rare congenital anomaly, in adults, the cleft may be an incidental finding that remains asymptomatic for years when the leak is well tolerated. 2D combined with 3D echocardiography is key for diagnosis and surgery guidance.

关键词： Mitral Regurgitation Isolated Mitral Cleft Adult Congenital Heart Disease Senegal

Production and Characterization of Biodiesel from Rapeseed Oil through Optimization of Transesterification Reaction Conditions

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Journal of Energy and Power Engineering 2019年第10期13卷 380-392页

作者： momar talla Dieng Takumi Iwanaga Yokoyama Christie Yurie Shuichi Torii Department of Advance Mechanical System Engineering Kumamoto UniversityKurokami2-39-1Kumamoto 860-8555Japan Laboratoire de Photonique Quantique d’Energie et de NanoFabrication Facultédes Sciences et TechniquesUniversitéCheikh Anta Diop de Dakar(UCAD)Dakar-Fann DakarB.P.5005Sénégal

In this study,biodiesel fuel was produced from rapeseed oil via transesterification *** optimum reaction conditions were determined by varying alcohol type and its concentration considering their influence on the yield and properties of produced *** and ethanol were alcohol used in the transesterification *** density of biodiesel was measured at 15℃according to EN ISO 12185 test method and its viscosity was determined at 40℃by using a Brookfield digital viscometer(DV-II+Pro).Shimadzu Auto-Calculating Bomb calorimeter CA-4AJ was used to measure the high heating *** optimum transesterification conditions found were alcohol:oil ratio of 18:1,1%of potassium hydroxide as catalyst,60 min of reaction time,60℃of reaction temperature and stirring speed of 650 *** properties under these conditions satisfied the regulatory standards and are slightly similar to those of mineral diesel tested in same *** methanol gives better results compared to ethanol.

关键词： Biodiesel transesterification reaction optimization process rapeseed oil.

Pest Management of Storage Pests Using Extracts of Afrostyrax lepidophyllus against Sitophilus zeama＇（s, Tribolium castaneum and Rhyzopertha dominica

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Journal of Agricultural Science and Technology(B) 2014年第1期4卷 58-66页

作者： Aba Toumnou Lucie gueye momar talla Bolevane Ouatinam Serge Florent Traore Anna gueye Sabelle Lakouetene Didier Ponel Beranger Namkosserena Salomon Ndoye Ousmane Syssa-Magale Jean-Lauren Noba Kandioura Sembene Mbacke Seck Dogo Faculty of Sciences University of Bangui Bangui Central Africa Republic lnstitut of Food Technology Dakar 3300 Senegal Regional Centre for Ecotoxicology Studies and Chemical Environment Security (CERES-Locustox) Dakar 3300 Senegal Regional Pole of Applied Research to Development Farming Systems in Central Africa (PRASAC) Bangui Central Africa Republic West and Central African Council for Agricultural Research and Development Dakar 18523 Senegal Faculty of Sciences Cheikh Anta Diop University Dakar 5005 Senegal

Chemical Characterization and Insecticidal Activity of Ethyl Acetate and Dichloromethane Extracts of Drypetes gossweileri against Sitophilus zeamais, Tribolium castaneum and Rhyzopertha dominica

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Journal of Life Sciences 2013年第10期7卷 1030-1040页

作者： Aba Toumnou Lucie Seck Dogo Lakouetene Didier Ponel Beranger Bolevane Ouantinam Serge Florent gueye momar talla Traore Anna Namkosserena Salomon Noba Kandioura Sembene Mbacke Syssa-Magale Jean-Laurent Regional Centre for Studies on the Improvement of Plant Adaptation to Drought Thies 3320 Senegal Regional Centre for Ecotoxicology Studies and Chemical Environment Security (CERES-Locustox) Dakar 3300 Senegal Department of Natural sciences University of Bangui Bangui 908 Central Africa Republic Institut of Food Technology Dakar 2765 Senegal Regional Pole of Applied Research to Development Farming Systems in Central Africa (PtL4SAC) N 'Djamena 764 Chad Department of Plant Biology Cheikh Anta Diop University Dakar 5005 Senegal Department of Animal Biology Cheikh Anta Diop University Dakar 5005 Senegal

The use of botanical pesticides in pest management during storage against insects is often encouraged because synthetic insecticides produce undesired effects. Bark powder of Drypetes gossweileri is used by farmers in pest management in Central Africa Republic. Hexane, dichloromethane, ethyl acetate and methanol were used for extraction bark powder by maceration. Insecticidal activity of the extracts was tested on Sitophilus zeamais, Tribolium castaneum and Rhyzopertha dominica. The mortality rate, the number of surviving insects and the number of emerged insects were measured variables. Calculated mortality was obtained by applying Aboth"s formula. The variables are submitted to variance analysis, model with four factors (plants, insects, doses and time) in Minitab 14. The results of analysis showed that the mortality rate has a very highly significant variation following extracts, doses, insects and time considered (P < 0.001). Extracts with ethyl acetate and dichloromethane of D. gossweileri are effective against S. zeamais and R. dominica at high doses (1, 0.5, 0.250 g/10 mL of solvent). These effective extracts were characterized by gas chromatography coupled with mass spectrometry. Molecules such as 1-isothiocyanatomethyl, thiocyanic acid, phenylmethyl ester and other were characterizated. These results may consolidate traditional use of D. gossweileri in pest management.

关键词：二氯甲烷乙酸乙酯化学表征杀虫活性多米尼加提取物玉米象赤拟谷盗

Photoionization Study of Cl II, Ar II and Kr II Ions Using the Modified Atomic Orbital Theory

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Journal of Modern Physics 2018年第14期9卷 2594-2622页

作者： Abdourahmane Diallo Mamadou Diouldé Ba Jean Kouhissoré Badiane momar talla Gning Malick Sow Ibrahima Sakho Department of Physics UFR Sciences and Technologies University Assane Seck of Ziguinchor Ziguinchor Senegal Department of Physics Faculty of Sciences and Techniques University Cheikh Anta Diop of Dakar Dakar Senegal

Resonance energies of the Cl II-[3s23p3(2D5/2)]nd and [3s23p3(2P3/2)]nd, Ar II-3s23p4(1D2)ns, nd and of the Kr II [4s24p4(1D2)]ns, nd and 4s24p4(3P2,3P1)]ns, 4s24p4(3D2)]ns, nd and 4s24p4(3D2, 1S0)]ns, nd Rydberg series are reported. Natural widths of the Ar II-[3s23p4(1D2)]ns, nd series are also reported. Calculations are done in the framework of the Modified Atomic Orbital Theory (MAOT). Excellent agreements are obtained with available theoretical and experimental data. High lying accurate resonance energies up to n = 40 are tabulated. The possibility to use the MAOT formalism report rapidly with an excellent accuracy the position of the excitation resonances as well as their width within simple analytical formulae is demonstrated.

关键词： Resonance Energies Rydberg Series Natural Widths Modified Atomic Orbital Theory (MAOT)

Variational Calculations of Energies of the (2snl) 1,3Lπand (2pnl) 1,3 LπDoubly Excited States in Two-Electron Systems Applying the Screening Constant per Unit Nuclear Charge

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Journal of Modern Physics 2021年第3期12卷 328-352页

作者： momar talla Gning Ibrahima Sakho Maurice Faye Malick Sow Babou Diop Jean Kouhissoré Badiane Diouldé Ba Abdourahmane Diallo Department of Physics Chemistry UFR Sciences and Technologies University of Thies Thies Senegal Department of Physics Faculty of Sciences and Techniques University Cheikh Anta Diop of Dakar Dakar Senegal Department of Physics UFR Sciences and Technologies University Assane Seck of Ziguinchor Ziguinchor Senegal

In this paper, resonance energies and excitation energies of doubly 2sns 1,3Se, 2snp 1,3P0, 2pnp 1,3De, 2pnd 1,3F0 and 2pnf 1,3Ge excited states of the helium isoelectronic sequence with Z ≤ 10 are calculated. Calculations are carried out in the framework of the variational procedure of the formalism of the Screening Constant per Unit Nuclear Charge (SCUNC). New correlated wave function of Hylleraas type is used. Precise resonance and excitation energies are tabulated and good agreement is obtained when a comparison is made with available literature values.

关键词： Doubly Excited States Helium Isoelectronic Sequence Screening Constant per Unit Nuclear Charge (SCUNC) Correlated Wave Function Resonance Energy Excitation Energies

Report of a New Case of Interlocking Heads in a Breech-Vertex Twin Delivery: A Conversation with My Residents

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Open Journal of Obstetrics and Gynecology 2021年第1期11卷 40-47页

作者： Mamour gueye Mouhamadou Wade Aissatou Mbodji Mame Diarra Ndiaye Ndiémé Mbaye Mor talla Ndiaye Rahadat Ibrahim Amadou Lamine Cisse Aliou Djiby Dia Aliou Cisse Moussa Diallo Omar Gassama Ousmane Thiam Magatte Mbaye Philippe Senghor Health Center Cheikh Anta Diop University Dakar Senegal

“Locked twins” is a rare event occurring in about 1 in every 1000 twin births. A 21-year-old primigravida with a 31-week twin pregnancy was admitted for delivery. The head of the first twin was locked to the chin of the second twin at the top of the symphysis pubis. Caesarean section was performed allowing the delivery of both dead twins. Twins gestations with first twin in the breech presentation raise index of suspicion of potential locked twin. However, management of such situation is controversial with most authors and colleges recommending caesarean section to avoid interlocking heads. We report another rare case of interlocking heads and bring up the topic about management of breech-first twin deliveries.

关键词： Interlocking Heads Breech Presentation Twins Recommendations

Validation of a Capillary Electrophoresis Method for Analyzing Chlorphenamine Maleate-Based Drugs Using the Accuracy Profile Approach

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American Journal of Analytical Chemistry 2016年第5期7卷 452-459页

作者： Serigne Omar Sarr Eddy Kevin Senan Ouendo Thierno Mouhamed Wane El Hadji Assane Diop Diop Amadou Serigne momar Ndiaye Rokhaya gueye Khadidiatou Thiam Aminata Sarr Ousmane Niass Djibril Fall Bara Ndiaye Serge Rudaz Yérim Mbagnick Diop Laboratory of Analytical Chemistry and Food Sciences Cheikh Anta Diop University Dakar Senegal National Medicines Control Laboratory Ministry of Health Dakar Senegal Laboratory of Pharmaceutical Analytical Chemistry School of Pharmacy Geneva Switzerland Laboratory of Organic and Therapeutic Chemistry Cheikh Anta Diop University Dakar Senegal

This study aimed at validating an analytical method, using the accuracy profile approach, for the assay of chlorphenamine maleate by capillary electrophoresis. The validation was done using concentrations ranging between 75% and 125% of the target concentration of 600 mg/ml. Validation standards were prepared separately in triplicate for each series. Studied validation criteria were selectivity, linearity, trueness, precision (repeatability and intermediate precision), accuracy and limits of detection and quantification. The method was selective, with recoveries ranging between 99.55% and 99.84%. The relative standard deviations of repeatability and intermediate precision were <5%. The accuracy profile confirmed the performance of the assay method between 75% and 100% of the target concentration of 600 mg/ml. The detection and quantification limits were 5 mg/l and 15 mg/l respectively. This ecological and economical method was applied to identify and quantify chlorphenamine maleate in 3 samples of chlorphenamine maleate-based drugs provided by the Senegalese National Medicines Control Laboratory. All analyzed samples were in accordance with official standards.

关键词： Analytical Validation Chlorphenamine Maleate Quality Capillary Electrophoresis CEB Senegal