检索结果-南通市图书馆

Comparative Geochemical Study of the Tertiary and Quaternary Lavas of Western Senegal and the Cape Verde Islands: Geodynamic Implications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Geosciences 2015年第11期6卷 1193-1213页

作者： Diomaye Yatte Dinna Pathé Diallo ibrahima Sagna Département de Géologie Université Cheikh Anta Diop Dakar Sénégal Institut Fondamental d’Afrique Noire (IFAN) Université Cheikh Anta Diop Dakar Sénégal

The western area of Senegal was the site of a basic volcanism in the Tertiary and Quaternary. That volcanism had caused the formation of alkaline olivine basalts, basanites and nephelinites from microlitic and porphyritic texture to dolerite texture. The geochemistry of major elements shows that the Quaternary basalts are more aluminous and more siliceous, but they contain less magnesium, less iron and less calcium than the Tertiary basalts. Two types of basalt occur here, based on the characteristics of the major elements in the Tertiary lavas: the highly undersaturated basalts of the Cape Verde Peninsula and the slightly undersaturated basalts of the Thiès Plateau. The characteristics of the trace elements reveal shallow interactions due to the contamination and/or assimilation, and to the fractional crystallization, but not due to the heterogeneity of the source. The strong enrichment in light rare earth elements (LREE) and the slight enrichment in heavy rare earth elements (HREE), the anomalies which are negative in K and Pb and positive in Nb, Ta and Eu of the Tertiary and Quaternary basalts of Western Senegal and similar anomalies of the same elements (Pb not analyzed) described in the Cape Verde islands, allow us to establish links between the petrogenetic mechanisms that had caused the formation of the basalts of this Islands and Western Senegal. Moreover, the volcanic activity in Western Senegal (of continental lntraplate type) and that of the Cape Verde Islands (oceanic intraplate type) are probably related to the hot spot located on the vertical of the Cape Verde.

关键词： Western Senegal Basalts Tertiary Quaternary Cape Verde

Analysis of Rainfall Dynamics in Conakry,Republic of Guinea

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Atmospheric and Climate Sciences 2020年第1期10卷 1-20页

作者： ibrahima Kalil Kante Saidou Moustapha Sall Daouda Badiane ibrahima Diouf Abdoul Lahat Dieng Idrissa Diaby Francoise Guichard Laboratoire de Physique de l’Atmosphère et de l’Océan Siméon Fongang École Supérieure PolytechniqueUniversité Cheikh Anta DiopDakarSenegal Direction Nationale de la Météorologie de Guinée ConakryGuinea Laboratoire d’Enseignement et de Recherche en Énergétique Appliquée UniversitéGamal Abdel Nasser de ConakryConakryGuinea NOAA Center for Weather and Climate Prediction College ParkUSA CNRM-GAME(CNRS and Météo-France) Toulouse CedexFrance

Observed rainfall data of the National Meteorological Service of Guinea (NMS) exhibit that synoptic station usually records the largest rainfall amount in Guinea. Only few studies have been done on this rainfall peak observed in Conakry. This work better analyses the atmospheric dynamics leading to rainfall particularity. Using NMS data from 1981 to 2010, the monthly contribution and mean seasonal cycle of each station has been done. These findings of the study show that between July and August (rainfall season peak), the coastline particularly Conakry records the largest amount of rainfall. Using Era Interim data for the common period (1981-2010), we also investigate the rainfall dynamics in the lower level (1000 hPa - 850 hPa) from precipitable water, divergence, and moisture flow transport. There is a west and southwest moisture flow transport explained by a strong moisture convergence in the coastal region (Lower-Guinea). Furthermore, values of precipitable water in the same region are found, in agreement with the high moisture flow transport gradient. These incoming flow (west and south-west) undergo a return by blocking’s Kakoulima range (foehn effect) and Fouta Djallon massif to initiate convection clouds on the Guinean coast. These processes enhance a convergence of moisture associated with orographic origin convection. This has an important effect by increasing the rainfall amount in Conakry.

关键词： Conakry Guinea Maximum Rainfall Precipitable Water Divergence Moisture Flow

Change in Climate Indices Using Bias-Adjusted CMIP5 Models: The Case Study of the Fatick Region, Senegal

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Climate Change 2022年第4期11卷 307-330页

作者： ibrahima Camara Quentin Lejeune Dimitri Defrance Mame Diarra Bousso Dieng Issa Sakho Youssouph Sane Mélinda Noblet Moussa Diakhaté Benjamen Sultan Saidou Moustapha Sall Sérigne Faye Laboratoire de Physique de l’Atmosphère et de l’océan Ecoloe Supérieure Polytechnique Université Cheikh Anta DIOP de Dakar Dakar Sénégal Climate Analytics Berlin Germany The Climate Data Factory Paris France Karlsruhe Institute of Technology (KIT) Institute of Meteorology and Climate Research-Atmospheric Environmental Research (IMK-IFU) Karlsruhe Germany Université Amadou Mahtar Mbow (UAM) Dakar Sénégal Agence Nationale de l’Aviation Civile et de la Météorologie (ANACIM) Dakar Sénégal Département de Géologie Faculté des Sciences et Techniques Université Cheikh Anta DIOP de Dakar Dakar Sénégal

This study analyses change in rainfall and temperature indices by 2035 and 2050 in Senegal, with a focus on the Fatick region. These parameters are crucial for understanding the impacts of anthropogenic climate change on some vital socio-economic sectors such as agriculture and water resources in this region. To this end, a multi model ensemble mean of 21 bias-adjusted global climate models participating in CMIP5 has been used. We considered two Representative Concentration Pathways (RCP4.5 and RCP8.5). The results indicate an increase of 0.7˚C for maximum and minimum temperature by 2035 compared to the reference period (1976 - 2005). By 2050, an increase of 1.4˚C (2˚C) is projected for RCP4.5 (RCP8.5). These increases in temperature are statistically significant at the 90% confidence level. Conversely, the mean rainy season length decreases from 95 to 85 days by 2035 and less than 80 days by 2050. These decreases in rainy season length are mainly due to a delayed rainy season onset by 2035 and 2050, with the ensemble mean projecting an onset in the second half of July by 2050 instead of around the middle of June. The changes in both the onset and the length of the rainy season are significant at the 90% confidence level. Our results show a slight decrease in seasonal cumulated total rainfall by 2035 and 2050. However, we note a slight increase in seasonal cumulated extreme rainfall. These future changes in climate indices could induce yield reduction and water resources availability. To reduce yield losses, it would be interesting to adopt longer season varieties and also diversify income-generating activities. Concerning water resources, many actions could be done such as carrying out water retention works, treatment and reuse of non-conforming water for agriculture and livestock to reduce pressure on the resource.

关键词： Climate Indices CMIP5 Fatick (Senegal) RCP4.5 and RCP8.5

Pyeloplasty According to Küss-Anderson-Hynes: Results and Complications at the Urology-Andrology Department of the Sino-Guinean Friendship Hospital

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Urology 2022年第9期12卷 471-477页

作者： Alimou Diallo Thierno Mamaou Oury Diallo Thierno Oumar Diallo Demba Cissé Sory Naby Camara Alpha Oumar Barry Mamadou Barry ibrahima Bah Abdoulaye Bobo Diallo Oumar Raphiou Bah Department of Urology Sino-Guinean Friendship Hospital Faculty of Health Sciences and Technologies Gamal Abdel Nasser University of Conakry Conakry Guinea National Ignace Deen Hospital Faculty of Health Sciences and Technologies Gamal Abdel Nasser University of Conakry Conakry Guinea National Ignace Deen Hospital Faculty of Health Sciences and Technologies Gamal Abdel Nasser University of Conakry Conakry Guinea Department of Urology Kolda Regional Hospital Cheick Anta Diop University Dakar Senegal

Objective: Evaluate pyeloplasty according to Küss-Anderson-Hynes at the urology-andrology department of the Sino-Guinean Friendship Hospital. Patient and Method: This is a 3-year prospective descriptive study from January 1, 2018 to December 31, 2020. It focused on a sample of 21 patients, who had undergone pyeloplasty according to Küss-Anderson-Hynes. Results: The averages age of the patients was 24.24 years. Lumbar pain was the main reason for consultation in 71.43% of cases. pyeloplasty according to Küss-Anderson-Hynes alone was performed in 76.20% of cases. It was associated with lower pole vessel uncrossing in 14.29% of cases and in 9.52% of cases with pyelolithotomy. The main Postoperative complications consisted of surgical site infections (23.81%) and fistula of the pyelo-ureteral junction (9.52%). The result of the pyeloplasty evaluated after three years, was qualified as good in 13 patients (86.67%), conversely the result was declared bad in 2 patients or 13.33%. During the follow-up period, postoperatively, we had lost sight of 6 patients. Conclusion: Pyeloplasty according to Küss-Anderson-Hynes in addition to its excellent results reported by the literature was the only therapeutic alternative performed during this study. However, its indications are considerably reduced with the advancement of laparoscopy.

关键词： Pyeloplasty Küss-Anderson-Hynes Parietal Suppuration

Minority Carrier Diffusion Coefficient <i>D</i>*(<i>B,T</i>): Study in Temperature on a Silicon Solar Cell under Magnetic Field

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy and Power Engineering 2017年第1期9卷 1-10页

作者： Richard Mane ibrahima Ly Mamadou Wade ibrahima Datta Marcel S. Douf Youssou Traore Mor Ndiaye Seni Tamba Grégoire Sissoko Laboratoire des Semi-conducteurs et d’Energie Solaire Facult&eacute des Sciences et Techniques Universit&eacute Cheikh Anta diop Dakar S&eacute né gal Ecole Polytechnique de Thiè s Thi&egrave s S&eacute né gal

This work deals with minority carrier diffusion coefficient study in silicon solar cell, under both temperature and applied magnetic field. New expressions of diffusion coefficient are pointed out, which gives attention to thermal behavior of minority carrier that is better understood with Umklapp process. This study allowed to determine an optimum temperature which led to maximum diffusion coefficient value while magnetic field remained constant.

关键词： Solar cell Diffusion Coefficient Temperature Magnetic Field

Domestic Accidents in Under-Fives: Epidemiology, Diagnosis, Management, and Outcomes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Pediatrics 2022年第5期12卷 726-736页

作者： Florent Tshibwid A. Zeng Papa Alassane Mbaye Doudou Gueye Papa Mamadou Ndoye ibrahima Bocar Wellé Ndeye Fatou Seck Mbaye Fall Ndeye Aby Ndoye Aloïse Sagna Oumar Ndour Gabriel Ngom Department of Pediatric Surgery Albert Royer National Children’s Hospital Centre Université Cheikh Anta Diop Dakar Senegal Department of Pediatric Surgery Aristide Le Dantec University Teaching Hospital Université Cheikh Anta Diop Dakar Senegal

Introduction: Domestic accidents are a public health problem, and under-fives are particularly affected. We report these accidents’ epidemiology, diagnosis, management, and outcomes through this study. Patients and Methods: We conducted a prospective descriptive study for four months in the Albert Royer National Children’s Hospital Center pediatric surgery department in Dakar, Senegal. Of the 149 cases of domestic accidents, 109 were included in this study. Results: Infants (59.6%) were the most affected, with a slight male predominance (50.5%). Accidents occurred on Tuesday in 22.9% of cases and the afternoon in 38.5% of cases. Playing (59.6%) was the main activity, and falling (44%) was the most found mechanism. 78.9% of accidents occurred in the house, with the bedroom (27.5%) being the most represented place. In most cases (67.9%), the consultation was done within the first 24 hours. The upper limbs (48.6%) were the most affected, and fractures (31.2%) were the most frequent injuries. The outcomes were unremarkable in 94.5% of cases, as complications occurred in five patients with three who had an infection, one a persistent limping, and the last, a dental avulsion. No mortality was recorded. Conclusion: Domestic accidents among under-fives are frequent in our environment. Compared to those in older children, they occur similarly in both sexes, more often in the bedroom, and have a better prognosis.

关键词： Domestic Accidents Under-Fives Infants Preschool Children Senegal

Effects of the Reynolds and Weissenberg’s Numbers on the Stability of Linear Pipe Flow of Viscous Fluid

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Modern Mechanical Engineering 2018年第4期8卷 264-277页

作者： ibrahima Kama Mamadou Lamine Sow Kodjo Kpode Cheikh Mbow Department of Physics University Cheikh Anta DIOP-UCAD Dakar Senegal Department of Physics University of Kara Kara Togo

A Fourier-Chebyshev Petrov-Galerkin spectral method is described for high accuracy computation of linearized dynamics for flow in a circular pipe. The code used here is based on solenoidal velocity variables and is written in FORTRAN. Systematic studies are presented of the dependence of eigenval-ues and other quantities on the axial and azimuthal wave numbers;the Reyn-olds’ number of up to 107 and the Weissenberg’s number that is considered lower here. The flow will be considered stable if all the real parts of the ei-genvalues obtained are negative and unstable if only one of these values is positive.

关键词： Viscoelastic Fluids Oldroyd-B Model Linear Stability Petrov-Galerkin Generalized Eigenvalue Problem

Geochemical CompGeochemical Comparison of Fresh and Weathered Tailings from the Sabodala Gold Mine Kedougou Region, Senegal Following 6 Years of Operationarison of Fresh and Weathered Tailings from the Sabodala Gold Mine Kedougou Region, Senegal Following 6 Years of Operation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Geoscience and Environment Protection 2020年第7期8卷 177-194页

作者： ibrahima Dia Mababa Diagne Mamadou Gueye Andrew Barnes Christian Mace Earth Sciences Institute Cheikh Anta Diop University Dakar Senegal Geochemic Ltd. Monmouthshire United Kingdom Teranga Gold Corporation Toronto Canada

The Sabodala gold mine is located in the Kedegou region in eastern Senegal near the border with Mali in a tropical Savannah climate zone with distinct wet and dry seasons. The mine has been operating since 2009 with active tailings deposition giving an ideal opportunity to study the weathering characteristics of carbonate rich tailings materials under real world conditions. The mine is operated in accordance with international best practice with regular monitoring of water quality and tailings chemistry in accordance with the international cyanide management code (ICMC) and also in order to monitor and control any potential impacts from Acid Rock Drainage and Metal Leaching (ARDML) that may be generated from the tailings materials and waste rock. In 2015 as part of a project looking at the potential for re-use of generated tailings as construction materials, a number of additional geochemical tests including whole rock assays, mineralogy, Acid Base Accounting in accordance with modified Sobek method with siderite correction, together with paste pH and electrical conductivity (Ec) measurements were undertaken. The purpose of the study was to update the predictions of the potential for ARDML generation and drainage pH in leachates forming from the Sabodala tailings. The tests were run on one composite weathered and 3 selective fresh samples collected by auger drilling on three holes over the tailing. Results have enabled a better understanding of the chemical weathering characteristics of finely ground tailings materials under tropical weathering conditions and the nature of secondary minerals precipitated.

关键词： Acid Base Accounting Neutralization Potential Elemental Analysis Mineralogy

Evisceration of the Small Bowel in the Vagina Following Endo-Uterine Maneuvers for Clandestine Abortion (APC) at CHU Gabriel Touré, Bamako, Mali

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Surgical Science 2018年第4期9卷 148-152页

作者： Dabo Aminata diop Thierno Madane Dembélé Bakary Tientigui Coulibaly Mahamadoun Doumbia Arouna Manganémoustapha Issa Abdoul Hamidou Almeimoune Traoré Alhassane Togo Adégné Téguété ibrahima Django Djibo Mahamane Diallo Gangaly Universal Resuscitation Service at Gabriel Touré Teaching Hospital Bamako Mali General Surgery Service of CHU Gabriel Touré Bamako Mali Department of Obstetric Gynecologyof CHU Gabriel Touré Bamako Mali

Intra-uterine manual aspiration is the recommended maneuver for abortive endo-uterine evacuation. It must be performed in a medical setting for therapeutic purposes, while respecting its contraindications and asepsis rules essential for its implementation. The ignorance of anatomical structures by the authors of clandestine abortions is marked by the presence of utero-adnexal lesions, digestive lesions and vesical lesions or evisceration by the vagina. Vaginal evisceration of the small bowel is a rare and serious complication of manual intrauterine aspirations and induced abortions. Their late diagnosis and clandestine practice are responsible for unpredictable severe secondary complications and remain an important cause of morbidity and mortality. The development of a policy of continuous training of agents on the technique of manual intrauterine aspiration, broad information on contraceptive methods and a multidisciplinary, rapid and adequate management of complications will provide minimum morbidity and mortality. Conclusion: Abortion is a serious source of life-threatening complications.

关键词： Evisceration Abortion Surgery Mali