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Influence of anthropic and eco-hydrological factors on the floristic diversity of the herbaceous vegetation around the temporary ponds in Ferlo,northern Senegal

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Journal of Plant Ecology 2022年第1期15卷 26-38页

作者： Ndiabou Faye Aly Diallo Moustapha BassimbéSagna Jean Luc Peiry papa saliou sarr Aliou Guisse Département de Biologie Végétale UniversitéCheikh Anta DiopDakarSenegal IRL3189 Environment SantéSociétésCentre National de la Recherche Scientifiques(CNRS)ParisFrance IRL3189 Environnement SantéSociétésUniversitéCheikh Anta DiopDakarSenegal Observatoire international Hommes Milieux-OHMi Tessekere UniversitéCheikh Anta DiopDakarSenegal Observatoire international Hommes Milieux-OHMi Tessekere Centre National de la Recherche Scientifique(CNRS)ParisFrance Departement d’Agroforesterie UniversitéAssane Seck de ZiguinchorZinguinchorSenegal Département de Géographie Universitéde Clermont FerrandClermont-FerrandFrance Japan International Research Center for Agricultural Sciences(JIRCAS) TsukubaIbarakiJapan

Temporary ponds play substantial roles in preserving biodiversity in the *** study investigated the influence of anthropic and eco-hydrological factors on the plant diversity around two grazed ponds and one ungrazed pond in Ferlo,northern *** phytoecological transects were established per *** each transect,homogenous herbaceous vegetation units were identified and characterized(herbaceous cover,exposure,soil texture,soil moisture and pH,average height and slope).The herbaceous flora comprised 55 species,41 genera and 22 families across the three *** of the Poaceae,particularly Eragrostis tremula and Enteropogon prieurii,mostly colonized the grazed ponds,while the ungrazed pond favored other families’species such as Achyranthes sp.,Commelina forsskaolii,Corchorus *** Shannon’s diversity index(H′)of Wendu Marodi(ungrazed pond)was slightly higher(4.9 bits)than that of Belel Lougal and Belel Sow(grazed ponds)with 4.8 and 4.5 bits,*** equitability indices were relatively high in the three ponds(0.85,0.83 and 0.78).Eco-ecological factors distinguished four species’groupings:a Tribulus terrestris grouping colonizing the constraining and over-grazed zones,a Digitaria horizontalis grouping,and Chloris barbata grouping found in the transition zones,and an Achyranthes aspera grouping in the wetlands,where woody plants were strongly present and the anthropic action *** study highlighted the importance of maintaining a landscape mosaic of ungrazed or semi-protected ponds and grazed ponds to preserve the herbaceous floristic diversity in the center of Ferlo(Senegal)and the Sahel in general.

关键词： ponds Ferlo grazing herbaceous vegetation transect

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Agro-Morphological Characterization of Cassava (Manihot esculenta Crantz) Cultivars from Chad

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Agricultural Sciences 2016年第7期7卷 479-492页

作者： Djirabaye Nadjiam papa saliou sarr Michel Naïtormbaïdé Jean Marie Mbaïlao Mbaïguinam Aliou Guisse Institut Tchadien de Recherche Agronomique pour le Développement (ITRAD) N’Djaména Tchad Département de Biologie Végétale Faculté des Sciences et Techniques (FST) Université Cheikh Anta Diop (UCAD) Dakar Sénégal Laboratory of Plant Gene Expression Research Institute for Sustainable Humanosphere Kyoto University Uji Japan Institut Tchadien de Recherche Agronomique pour le Développement (ITRAD) Centre Régional de Recherche Agronomique pour la Zone Soudanienne Station de Bébédjia Moundou Tchad Université des Sciences et des Technologies Ati Tchad Observatoire Homme Milieux Téssekeré (OHM-Téssekeré) Université Cheikh Anta Diop de Dakar Dakar Sénégal

Cassava is a considerable source of food and income for the rural community of the south of Chad. Despite the importance of the diversity of cultivars in situ, their morphological traits and agronomic performance are under investigated. The aim of this study is to characterize and analyze the variability structure of the cassava’s germplasm. Fifty nine cultivars collected from five main cassava growing regions, were evaluated by forty five agro-morphological descriptors in a Fisher design replicated three times. Data were collected at three, six, nine and twelve months after planting. High phenotypic variability was shown within the collection for the color of apical leaf, vein leaf, petiole, roots and pulp. The same case was observed for the root peduncle, the shape of the central leaflet and the root, the cortex root thickness and the texture of root epidermis. Significant to highly significant differences were observed for all the quantitative traits. High variability were shown for the size of the leaf lobe, petiole length, plant height, root number and length, harvest index, above-ground biomass and fresh root weight. Positive correlations were found between the leaflet and leaf lobe number. Fresh root weight was also positively correlated to the root number, length and diameter. Principal component analysis (PCA) on quantitative variable revealed four groups with two of them containing performant cultivars: Group II with small root, high potential yield but less leaflet and leaf lobe and group III characterized by some cultivars with high productivity, more leaflet and leaf lobe, more and bigger roots. At regional level, significant differences were shown within cultivars which were discriminated in relation to their origin region by the number of the leaf lobes. The better cultivars and the interesting traits could be used to improve cassava production in Chad.

关键词： Variability Traits Cassava Cultivars Local Improved Chad

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Dendrochronological Potential and Impact of Climate Factors on Radial Growth of Two Species in the Sahelian Zone: <i>Boscia senegalensis</i>(Pers.) Lam. ex Poir and <i>Sclerocarya birrea</i>(A. Rich) Hoscht (Ferlo Nord/Senegal)

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American Journal of Plant Sciences 2021年第4期12卷 498-517页

作者： Ramata Talla Moustapha Bassimbé Sagna Daouda Ndiaye Aly Diallo Jean Luc Peiry papa saliou sarr Aliou Guisse Department of Plant Biology Cheikh Anta Diop University Dakar Senegal Observatoire Homme-Milieux International de Tessekere CNRS/Universite Cheikh Anta Diop Dakar Senegal UMI 3189 “Environnement Sante Societes” UGB UCAD CNRS CNRST USTTB Dakar Senegal Department of Agroforestry Assane Seck University Ziguinchor Senegal Maison des Sciences de l’Homme 4 University of Clermont Ferrand-Geolab-UMR 6042 Rue Ledru Clermont-Ferrand France Japan International Research Center for Agricultural Sciences (JIRCAS) Ibaraki Japan

The objective of this study is to analyze the dendrochronological potential of two Sahelian species (B. senegalensis and S. birrea) and to evaluate the relationships between their growth rings and the climate. The study was conducted in 2016 in the Ferlo area of Senegal. The biological material consists of wood slices, taken from the trunks of these adult woody species at 0.30 m and 1.30 m from the ground after they have been felled. The technique used to examine the slices consists in identifying their rings, establishing their structures, inter-dating them and studying the relationship between the identified rings and climatic factors. The results showed that the species had thin, clear, highly visible and sharp rings. The limit of growth is marked by a line of parenchyma. Intradatation series carried out on the chronologies made it possible to estimate the ages of the individuals, which vary from 10 to 38 years for B. senegalensis and from 29 to 50 years for S. birrea. Their average growth rates are estimated at 0.906 mm/year and 0.89 mm/year respectively. The chronological sequences are 29 years (1987-2016) for B. senegalensis and 38 years (1964-2012) for S. birrea. The results revealed that there is no significant correlation between the growth chronologies of

关键词： Dendrochronology Cerne Climate Boscia senegalensis Sclerocarya birrea Ferlo

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Temporo-spatial dynamics and behavioural patterns of 2012 cholera epidemic in the African mega-city of Conakry,Guinea

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Infectious Diseases of Poverty 2018年第1期7卷 145-154页

作者： Alexandre Blake Veronique sarr Keita Delphine Sauvageot Mamadou saliou Berthe Marie Njanpop Fode Sory Bertrand Sudre Koivogui Lamine Martin Mengel Bradford DGessner Keita Sakoba Agence de Medecine Préventive ParisFrance Division Prevention et Lutte contre la Maladie(DPLM) Ministere de la santéPublique et de l’Hygiene Publique ConakryConakryGuinea Institut National de Sante Publique(INSP) ConakryGuinea Franche-Comtéuniversity(UMR 6249 chrono-environnement) BesançonFrance.

Background:Cholera is endemic in Guinea,having suffered consecutive outbreaks from 2004 to 2008 followed by a lull until the 2012 *** we describe the temporal-spatial and behavioural characteristics of cholera cases in Conakry during a three-year period,including the large-scale 2012 ***:We used the national and African Cholera Surveillance Network(Africhol)surveillance data collected from every cholera treatment centre in Conakry city from August 2011 to December *** prevalence of suspect and confirmed cholera cases,the case fatality ratio(CFR),and the factors associated with suspected cholera were described according to three periods:pre-epidemic(A),epidemic 2012(B)and post epidemic(C).Weekly attack rates and temporal-spatial clustering were calculated at municipality level for period *** was confirmed by culture at the cholera national reference ***:A total of 4559 suspect cases were reported:66,4437,and 66 suspect cases in periods A,B and C,*** the 204 suspect cases with culture results available,6%,60%,and 70%were confirmed in periods A,B,and C,*** 0.3%,the CFR was significantly lower in period B than in periods A(7.6%)and C(7.1%).The overall attack rate was 0.28%in period B,ranging from 0.17%to 0.31%across ***,a cluster of cases was identified in two districts in the northern part of *** 14%,rice water stools were less frequent in period A than in period B and C(78%and 84%).Dehydration(31%vs 94%and 89%)and coma(0.4%vs 3.1%and 2.9%)were lower during period B than in periods A and *** treatment of drinking water was less frequent in period A,while there were more reports of recent travel in period ***:The epidemic dynamic and the sociological description of suspect cases before,during,and after the large-scale epidemic revealed that the Vibrio cholerae was already present before the ***,it appeared that infected individuals react

关键词： Cholera Space-time clustering Guinea

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Experimental Analysis to Extract the Maximum Output of Serial and Parallel PV Module Configurations under Partial Shadow Conditions: A Case Study for Bambey, Senegal

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Energy and Power Engineering 2022年第7期14卷 233-247页

作者： Cheikh saliou Toure papa Lat Tabara Sow Fakora Dia Senghane Mbodji Renewable Energies Materials and Laser (ERML) Alioune DIOP University of Bambey Bambey Senegal

Using an experimental setup, the series configurations (SC) and the parallel configurations (PC) of the PV cell connection are studied to compare their performance under the condition of partial shading s. The performance of the configurations is evaluated by comparing the open-circuit voltage, the short-circuit current, the maximum power point (MPP), the voltage and current corresponding to MPP, and the Fill Factor (FF). The variations of the series resistance and the shunt resistance of a PV module under different irradiance levels are also determined by considering the effect of thermal voltage. Finally, a comparison between the performance losses in the different configurations is presented. The results of this study show that the parallel configuration has the best performance under the conditions of partial shade in the context of this work.

关键词： PV Cell Partial Shading Series Configurations (SC) Parallel Configurations (PC) Fill Factor (FF) Maximum Power Point (MPP)

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Study of HIV Prevalence and Behaviors in Rural Areas of Goudomp Health District (Senegal)

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World Journal of AIDS 2020年第2期10卷 69-79页

作者： Niang Khadim Anne Malick sarr Assane Thiam Ousmane Ndiaye papa Public Health Department Gaston Berger University (UGB) of Saint-Louis Saint-Louis Senegal Goudomp Health District Sedhiou Region Senegal Obstetrics and Gynecology Department Gaston Berger University (UGB) of Saint-Louis Saint-Louis Senegal

This study aims to determine the factors related to HIV-positive status in people aged 15 to 49 years of age in the commune of Niagha in Goudomp. The study was descriptive and analytically cross-cutting and had taken place in a release of 2018. The data was collected on anonymous questionnaires and then analyzed using R software after entering with Epi 7 software. Bivariate analyses and logistical modelling have been used to investigate the factors associated with HIV status. The sample included 400 people, and a participation rate of 100% was obtained in relation to the administration of the questionnaire. For the detection of HIV infection, 318 people agreed to do so, a proportion of 79.7%. The average age of the respondents was 27.8 years with a standard deviation of 9.1 and extremes of 15 to 49 years. 21.5% of respondents were under 20 years of age, the median was 26 years. With 58.8% of women, the sex ratio (M/F) was 0.7. In this study, 11.5% of respondents did not believe in the existence of HIV infection, 92.0% were sexually active, and 40.5% had sex with casual partners. The main places for casual sex were cultural events (84.0%), weekly markets (53.1%), religious events (27.8%) and during travel (22.8%). Among them, only 20 respondents, or 12.3%, declared that they systematically protect themselves with a condom during these occasional sexual relations. This wearing of condoms was found in 20.7% of singles and 10.7% of married couples having casual sex. In this study, 60.0% of the respondents declared that they had paid for sex, although this practice is not cited in income-generating activities. Non-consensual sex was found in 6.5% of the respondents. In this study, 319 people agreed to be tested for HIV, or 79.7% of the sample. HIV infection was found in 19 people, 6.0% seroprevalence, with 16 cases of HIV 1 infection and three cases of HIV 2 infection. Several risk behaviors were found in this study. However, none of them had a statistically significant

关键词： HIV Risky Behaviors IST Prevalence Senegal

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Mechanical Behavior of Pillow Lavas in MakoSupergroup: Case of South Mako Hill

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International Journal of Geosciences 2011年第4期2卷 640-647页

作者： Déthié sarr Meissa Fall papa Malick Ngom Mapathé Ndiaye 不详

This work shows the Kédougou-Kéniéba inlier (eastern Senegal) pillow lavas behavior from laboratory to field. Some uniaxial tests are carried out on five types of specimens of pillow lavas. These types of specimens are: macroscopicly healthy rock, fractured rock without filling, fractured rock filled with epidote, chlorite and calcite and rocks with tension crack filled with quartz. The Young moduli and the uniaxial compression strength are good for the healthy rock. The Young moduli fall slightly for facies with horizontal cracks while uniaxial compression strength (Rc) varies slightly. For filled fractured specimens, Rc and Young modulus (E) decrease remarkably. Decreases are most important for cracks filled with epidote, chlorite and calcite than with quartz. That is due to the differences of rigidity between these materials. Also, the slope stability of hillsides in this area depends on to these characteristics.

关键词： Unconfined Compression Test-Uniaxial Compression Strength (UCT Rc) JRC (Joint Roughness Coefficient) Young Modulus (E) Roughness Kédougou-Kéniéba Inlier Linea-ments Discontinuities Dihedral Slope Hillside

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New Approach of Geomechanical Properties by Scale Effect and Fractal Analysis in the Kedougou-Kenieba Inlier (Senegal-West Africa)

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Geomaterials 2013年第4期3卷 145-155页

作者： Déthié sarr Meissa Fall papa Malick Ngom Mamadou Gueye Département de Géologie FST-UCAD Université Cheikh Anta Diop de Dakar Dakar Sénégal Institut des Science de la Terre FST-UCAD Université Cheikh Anta Diop de Dakar Dakar Sénégal Laboratoire de Mécanique et Modélisation UFR Sciences de l’ Ingénieur Université de Thiès Thiès Sénégal

This paper shows geometric aspects of rock masses in the Senegalese side of Kédougou-Kéniéba inlier. The studies are done in one part on sedimentary rocks (represented by sandstones) with stratification and on the other part in igneous rocks (represented by basalts). Geometric studies are the fractal configuration and the scale effect. Scale effect is stud- ied by comparing the results of mechanical tests done in the laboratory and on outcrops. For all samples, laboratory pa- rameters are higher than values of field. In this paper, scale effect is characterized by the decrease of mechanical pa- rameters from laboratory samples to field. The scale coefficient is defined and characterizes the relation between me- chanical properties. More importantly, the scale effect is more significant. This scale effect depends largely on the rock anisotropy. The anisotropy depends on the fracturation and the filling. The scale effect takes into account the fracturation, the filling minerals and their diversity which define the complexity of the rock. The anisotropy is complex;the impact of scale effect traduced by an increase of scale coefficient is the highest. Configuration of discontinuities also defines fractal geometry. This fractal aspect appears on the asperities, the spacing and the apertures of discontinuities. The fractal dimension is different from a parameter to another. All these two parameters estimate the stage of fracturation of the rock in a geological system and depend one on another if they are studied in the same element.

关键词： Rock Scale Effect Fractal Kédougou Sedimentary Igneous

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Cartography of Landslide Susceptibility around the Dias Horst and Thies Cliff-Senegal

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International Journal of Geosciences 2017年第6期8卷 821-836页

作者： Issa Ndoye Mapathé Ndiaye Déthié sarr papa Sanou Faye Ibrahima Khalil Cissé Laboratoire de Mécanique et Modélisation UFR Sciences de l’Ingénieur Université de Thiès Thiès Sénégal Laboratoire de Mécanique des Sols et des Matériaux Ecole Polytechnique de Thiès Thiès Sénégal

The aim of this work is to map the susceptibility of sites to landslides. To assess the susceptibility of the zone, GIS techniques were used. Susceptibility factors are selected and split into two groups: active and passive factors. Passive factors regroup all the intrinsic conditions existing on the field at all times. The active factors or triggering factors are present sporadically and are added to the passive factors to trigger a landslide. With the weighted overlay method using ArcGIS?, four scenarios have been developed. A first scenario where only passive factors are combined and three scenarios for which we have for each scenario the passive factors combined with an active factor. With these different scenarios, five levels of susceptibility are obtained in the zone. These levels range from very low to very high susceptibility. For the different scenarios, the results show that the zone consists mainly of very low to low susceptibility with at least 61% of the area, followed by moderate susceptibility (23.54% to 38.24%) and last land with high susceptibility to very high with less than 1% of the surface. Fields with high to very high susceptibility are located on the slopes of the hills. Among the active factors, only the rainfall significantly modifies the percentage of land susceptible to landslide but remains in the field of moderate susceptibility. The predicted susceptibilities are closer to the observed landslides around the Thies Cliff than to the Dias Horst.

关键词： Cartography Susceptibility Landslides Dias Horst Thies Cliff

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Space and Temporal Distribution Analysis of Interictal Spike in Epilepsy

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Journal of Life Sciences 2012年第8期6卷 840-847页

作者： Mamadou Lamine Ndiaye Jean-Jacques Montois Abel Kinie papa Alioune sarr Ndiaye Laboratoire Traitement du Signal et de l 'Image INSERM U 642 Rennes 35000 France Centre International de Formation et de Recherche en Energie Solaire CIFRES ESP-UCAD BP 5085 Dakar Senegal

Stereo-electroencephalography （SEEG） is the main investigation method for pre-surgical evaluation of patients suffering from drug-resistant partial epilepsy. SEEG signals reflect two types of paroxysmal activity： ictal activity and interictal activity or interictal spikes （IS）. The relationship between IS and ictal activity is an essential and recurrent question in epiletology. In this paper, we present a distributed and parallel architecture for space and temporal distribution analysis of IS, based on a distributed and collaborative methodology. The proposed approach exploits the SEEG data using vector analysis of the corresponding signals among multi-agents system. The objective is to present a new method to analyze and classify IS during wakefulness （W）, light sleep （LS） and deep sleep （DS） stages. Temporal and spatial relationships between IS and seizure onset zone are compared during wakefulness, light sleep and deep sleep. Results show that space and temporal distribution for real data are not random but correlated.

关键词： Epilepsy sleep stage stereo-electroencephalography (SEEG) interictal spike signal processing multi-agent system.

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