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Immunovirological Discordance and Associated Factors among People Living with HIV under Antiretroviral Treatment at Hôpital de Jour de Donka, Guinea
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作者 Mariama Sadjo Diallo Djiba Kaba +12 位作者 Charles Tchibinda Delicat Issiaga Diallo Boh Fanta Diane Doufin Traore Ousmane Niabaly Oumar Mouctar Diallo Ouo-Ouo Yaramon Kolie Aly Patrice Kamano Pascal Koivogui Ahmed Sékou Keita Mohamed Macire Soumah Thierno Mamadou Tounkara Mohamed Cisse 《Open Journal of Medical Microbiology》 2024年第2期93-104,共12页
The antiretroviral treatment (ART) has significantly reduced the number of new HIV/AIDS infections and related deaths. However, cases of immunovirological discordance (IVD) are found in various locations. The objectiv... The antiretroviral treatment (ART) has significantly reduced the number of new HIV/AIDS infections and related deaths. However, cases of immunovirological discordance (IVD) are found in various locations. The objective of this study was to determine the profile of People living with HIV (PLHIV) with IVD and to identify associated factors. We conducted a cross-sectional study based on the records of PLHIV under ART for at least 6 months, followed at Hpital de Jour Donka from 2015 to 2017, and having both viral load (CV) and CD4 T-cell count. Prevalence of IVD was 34.57%, with 23.87% for immunological discordance (ID) and 10.7% for virological discordance (VD). Females were predominant (66.26%), and male gender influenced IVD with a statistically significant difference (p = 0.006) and was associated with VD (p = 0.007). The average age was 38.77 11.30 years. PLHIV were classified at WHO stages 3 and 4 (86.01%). The median initial haemoglobin level was 11.5 g/L [3.2 - 12]. The mean initial CD4 T-cell count was 272.84 cells/mm3 201.6. The median initial viral load (VL) was 147,337 copies/mL [1092 - 31,675,000]. The initial CD4 T-cell count 3 was associated with IVD with a statistically significant difference (p = 0.0009) and correlated with ID (p = 0.000). Prurigo was associated with IVD with a statistically significant difference (p = 0.003). Cerebral toxoplasmosis was not associated with IVD but was associated with ID (p = 0.04). This study allowed us to describe the profile of PLHIV with IVD. The main associated factors were male gender, initial CD4 T-cell count 3, toxoplasmosis, prurigo, and herpes zoster. 展开更多
关键词 HIV Antiretroviral Treatment (ART) Immunovirological Discordance Donka GUINEA
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Could ERA5 Deliver Better Climate Services Than ERA-Interim over the West African Sahel Region?
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作者 Mahamane Rabilou Iro Ousmane Inoussa Abdou Saley +5 位作者 Saidou Chaibou Abdoul Aziz Mounkaila Saley Moussa Kone Diakaria Ibrah Seidou Sanda Manga Ousmane Adamou Dungall Laouali 《Journal of Environmental Science and Engineering(B)》 CAS 2024年第4期144-158,共15页
Our paper assessed the improvement performance of the reanalysis(ERA5)compared to ERAI(ERA-Interim)both from the ECMWF(European Center for Medium-Range Weather Forecast)in representing the WAM(West African Monsoon)dyn... Our paper assessed the improvement performance of the reanalysis(ERA5)compared to ERAI(ERA-Interim)both from the ECMWF(European Center for Medium-Range Weather Forecast)in representing the WAM(West African Monsoon)dynamic.Our aim is to evaluate the reliability of ERA5 to deliver better climate services than ERAI in the West African Sahel region.Two complementary observational databases namely the CRU(Climate Research Unit)and the GPCC(Global Precipitation Climatology Center)data are used to evaluate precipitation and temperature representation by the two reanalysis.Otherwise,the representation of some major features of the WAM system,such as the SHL(Saharan Heat Low),the AEJ/TEJ(African and Tropical Easterly Jets)was assessed using the two reanalysis data.The obtained results show a better representation of the seasonal accumulated precipitation and average temperature by ERA5 compared to ERAI with higher spatial correlation and lower bias relative to the observations.Furthermore,ERAI appears to be rainier than ERA5 but ERA5 produces more heavy rainfall days.During the period of intense monsoon,the frequency of the SHL is higher for ERAI which would favor intensification of monsoon inflow and depth.The lower SHL frequency observed in the ERA5 could explain the observed weakening intensity of AEJ which is favorable for moist conditions over the Sahel.These findings confirm the progress made by ERA5 compared to ERAI in representing the WAM dynamic and demonstrate its reliability for delivering better climate services over the West African Sahel. 展开更多
关键词 ERA5 ERAI West African Monsoon System SAHEL SHL
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A New Multiobjective Particle Swarm Optimization Using Local Displacement and Local Guides
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作者 Saïd Charriffaini Rawhoudine Abdoulhafar Halassi Bacar 《Open Journal of Optimization》 2024年第2期31-49,共19页
This paper introduces a novel variant of particle swarm optimization that leverages local displacements through attractors for addressing multiobjective optimization problems. The method incorporates a square root dis... This paper introduces a novel variant of particle swarm optimization that leverages local displacements through attractors for addressing multiobjective optimization problems. The method incorporates a square root distance mechanism into the external archives to enhance the diversity. We evaluate the performance of the proposed approach on a set of constrained and unconstrained multiobjective test functions, establishing a benchmark for comparison. In order to gauge its effectiveness relative to established techniques, we conduct a comprehensive comparison with well-known approaches such as SMPSO, NSGA2 and SPEA2. The numerical results demonstrate that our method not only achieves efficiency but also exhibits competitiveness when compared to evolutionary algorithms. Particularly noteworthy is its superior performance in terms of convergence and diversification, surpassing the capabilities of its predecessors. 展开更多
关键词 Particle Swarm Optimization Multiobjective Optimization Attractor-Based Displacement Square Root Distance Crowding Distance
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Using Multiple Linear Regression and Artificial Neural Network Techniques for Predicting CCR5 Binding Affinity of Substituted 1-(3, 3-Diphenylpropyl)-Piperidinyl Amides and Ureas
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作者 Rokaya Mouhibi Mohamed Zahouily +1 位作者 Khalid El Akri Naima Hanafi 《Open Journal of Medicinal Chemistry》 2013年第1期7-15,共9页
Quantitative structure–activity relationship (QSAR) models were developed to predict for CCR5 binding affinity of substituted 1-(3, 3-diphenylpropyl)-piperidinyl amides and ureas using multiple linear regression (MLR... Quantitative structure–activity relationship (QSAR) models were developed to predict for CCR5 binding affinity of substituted 1-(3, 3-diphenylpropyl)-piperidinyl amides and ureas using multiple linear regression (MLR) and artificial neural network (ANN) techniques. A model with four descriptors, including Hydrogen-bonding donors HBD(R7), the partition coefficient between n-octanol and water logP and logP(R1) and Molecular weight MW(R7), showed good statistics both in the regression and artificial neural network with a configuration of (4-3-1) by using Bayesian and Leven-berg-Marquardt Methods. Comparison of the descriptor’s contribution obtained in MLR and ANN analysis shows that the contribution of some of the descriptors to activity may be non-linear. 展开更多
关键词 Artificial Neural Network DESCRIPTORS CCR5 Multiple Linear Regression Structure-Activity Relationship
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Contribution to the Study of Paleoproterozoic Materials for the Improvement of Social Housing in the Kedougou Region: Case of Mako Andesitic Meta-Tuffs
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作者 Abdou Diouf Adama Dione +1 位作者 Mahamadane Diene Matar Ndiaye 《Journal of Building Construction and Planning Research》 2020年第1期42-56,共15页
The objective of this project is the valorization of Mako andesitic volcanic tuffs for use in social housing in the Kedougou region. To achieve these objectives, a geotechnical characterization of the tuff samples was... The objective of this project is the valorization of Mako andesitic volcanic tuffs for use in social housing in the Kedougou region. To achieve these objectives, a geotechnical characterization of the tuff samples was carried out and the geopolymerization stabilization was adopted for the manufacture of bricks. These bricks stabilized by an alkaline activation offer compressive strengths that exceed the threshold value (2.9 MPa) set by the standard (NF P14-304). The best compressive strengths (12.14 MPa) and flexural tensile strengths (5.43 MPa) are obtained in the series of bricks made with 35% of the mass of a solution of caustic soda at 12 molars concentration with a curing temperature cooking of 185°C and an average absorbance of 13.21%. 展开更多
关键词 Mako VOLCANIC TUFFS Geopolymerization ALKALINE Activation
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Qualitative Assessment of Table Salt Production Techniques in Southern Benin Republic, and Related Mangrove Destruction and Health Issues
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作者 Julien Adounkpe Cyriaque Agboton +3 位作者 Waliou Amoussa Hounkpatin Basile Kounouhewa Clement Ahouannou Brice Sinsin 《Food and Nutrition Sciences》 2021年第7期759-773,共15页
This research was conducted in the framework of the feasibility study related to FOCUSED-Benin project, the 5</span><sup><span style="font-family:Verdana;">th</span></sup><sp... This research was conducted in the framework of the feasibility study related to FOCUSED-Benin project, the 5</span><sup><span style="font-family:Verdana;">th</span></sup><span style="font-family:Verdana;"> work package of the YES-PV NIG BEN project financed by the German Government through its Ministry of Research and High Education (BMBF). The FOCUSED Benin project’s major objective is to protect the environment through the utilization of solar energy for drying</span><span style="color:red;"> </span><span style="font-family:Verdana;">agricultural products and table salt harvesting. Salt is important in human daily life. It is used for conservation of food, softening water, industrial processes, road de-icing, food seasoning, etc. Seawater evaporation, salt mining, and salt brine are the major sources of salt production worldwide. However, in West Africa, particularly in Benin Republic, table salt is produced using methods that negatively impact the ecology of the mangrove. This study aimed at investigating the current status of salt production in Benin Republic, its impact on the mangrove and its related health issues. Field visits, meeting with associations of women salt producers in the co</span><span style="font-family:Verdana;">astal region of the country, allowed to quantify the number of women associations dealing with salt production, their difficulties, and the impacts on the m</span><span style="font-family:Verdana;">angrove. Salt is a seasonal activity and is produced from January to May. One kilogram salt production, along with health issues reported by salt producers, requires approximately 1</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">kg of firewood obtained by cutting down mangrove. Salt price varies from 250CFA </span><a name="_Hlk67640154"></a><span style="font-family:Verdana;">(€0.38) to 400FCFA (€0.61) per kg depending on the season. The women salt producers are not aware of the ecological consequences of mangrove destruction. Sources of firewood are becoming increasingly scarce and prices prohibitive. Sensitization is not efficient. An alternative method of harvesting salt by solar drying and new ideas for implementing this activity in a participatory approach w</span></span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> discussed with the different associations of salt producers. 展开更多
关键词 Table Salt BRINE Seawater Ecology MANGROVE Health Issues
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Insight into Genetic Diversity of Cultivated Lima Bean (Phaseolus lunatus L.) in Benin
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作者 Rose Fernande Fagbédji Lambert Gustave Djedatin +4 位作者 Chimène Nanoukon Geofroy Kinhoegbe Amed Havivi Hounnankpon Yédomonhan Clément Agbangla 《American Journal of Molecular Biology》 CAS 2023年第1期32-45,共14页
Lima bean is a tropical and subtropical legume from the genus Phaseolus which is cultivated for its importance in food and in medicine, but which remains a Neglected and Underutilized Crop in Benin. Understanding the ... Lima bean is a tropical and subtropical legume from the genus Phaseolus which is cultivated for its importance in food and in medicine, but which remains a Neglected and Underutilized Crop in Benin. Understanding the genetic diversity of a species’ genetic resources is useful for the establishment of appropriate conservation strategies and breeding programs and for sustainable use. We use 6 out of ten SSR markers to analyze the diversity and population structure of 28 Lima bean landraces collected in Benin. A total of 28 alleles with an average of 4.16 alleles per SSR were amplified. The Polymorphic Information Content value ranged from 0.079 to 0.680 with an average of 0.408. The analysis of population structure revealed three subpopulations. PCoA revealed three well-separated clusters among the analyzed accessions in accordance with the population structure results and the clustering based on the Neighbor-Joining tree. AMOVA showed highly significant (p = 0.001) diversity among and within populations. Hence, 32% of the genetic variation was distributed among the population and 68% was distributed within populations. A high PhiP value (0.321) was found between the three sub-subpopulations indicating a high genetic differentiation between these sub-subpopulations. By exhibiting the highest average number of alleles, Shannon-Weaver information and Shannon-Weaver diversity indices, and the highest mean number of private alleles, subpopulation 1 is the main gene pool of the analyzed collection. The present study is an important starting point for the establishment of appropriate conservation strategies and breeding programs for Lima bean genetic resources. 展开更多
关键词 Phaseolus lunatus L. BENIN Genetic Diversity SSR Markets CONSERVATION
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Characterization of the Natural and Organomodified Clay Soil of Moukosso (Republic of Congo) by Dimethylsulfoxide: Application to the Adsorption of Lead (II) in Aqueous Solution
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作者 Ottard Arnaud M. R. Ossiby Mwa Ngo Ferland Ngoro-Elenga +3 位作者 Erman E. Nzaba Madila Zita F. Diamouangana Mpissi Exaucé R. Kinzonzi Ngongot Joseph Marie Moutou 《Materials Sciences and Applications》 CAS 2023年第2期63-77,共15页
In this study, the authors characterized the raw clayey soil of Moukosso and modified by dimethylsulfoxide (DMSO) by several analytical methods, namely: X-ray diffraction (XRD), Fourier transform infrared (FTIR) and g... In this study, the authors characterized the raw clayey soil of Moukosso and modified by dimethylsulfoxide (DMSO) by several analytical methods, namely: X-ray diffraction (XRD), Fourier transform infrared (FTIR) and gravimetric thermal analysis (TGA). The cation exchange capacity (CEC) was also determined. Mineralogical analysis by XRD revealed the presence of muscovite (29.7%), kaolinite (8.9%), anatase (2.4%) and quartz (58.9%). The characterization of the organo-clay by infrared and by thermogravimetric analysis confirmed the intercalation of DMSO by the presence of vibration bands at 1008 cm<sup>-1</sup> and 1070 cm<sup>-1</sup> and a strong increase in the loss of mass. The cation exchange capacity of the raw material is 7.4 meq/100g. Rapid adsorption of Pb<sup>2+</sup> ions was observed between 5 and 15 minutes of stirring time in both cases (raw clay and organomodified clay). The modeling of the isotherms by the models of Langmuir and Freudlich showed that these are of type S with a maximum amount of adsorption of 22.471 mg/g for the fine fraction and 41.493 mg/g for the clay intercalated with DMSO. Langmuir’s model best reproduces the experimental data of this study. 展开更多
关键词 Clay DIMETHYLSULFOXIDE ORGANOCLAY CHARACTERIZATION ADSORPTION ISOTHERM Moukosso
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16S rRNA Gene-Based Metagenomic Analysis of Soil Bacterial Diversity in Brazzaville, Republic of the Congo
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作者 Irène Marie Cécile Mboukou Kimbatsa Itsouhou Ngô +4 位作者 Armel Ibala Zamba Faly Armel Soloka Mabika Thantique Moutali Lingouangou Joseph Goma-Tchimbakala Etienne Nguimbi 《Advances in Microbiology》 2023年第9期477-498,共22页
Soil contains a great diversity of microorganisms, among which are bacteria. This study aimed to explore bacterial diversity in soil samples in Brazzaville in the Republic of the Congo. Environmental DNA was extracted... Soil contains a great diversity of microorganisms, among which are bacteria. This study aimed to explore bacterial diversity in soil samples in Brazzaville in the Republic of the Congo. Environmental DNA was extracted. The illumina MiSeq sequencing was held and the diversity indices have been computed. Illumina MiSeq sequencing revealed 21 Phyla, four of which were abundant: Proteobacteria, Acidobacteria, Actinobacteria and Bacteroidetes. Soil microbial communities in the studied samples were phylogenetically diverse but with a stable community structure. 17 classes are represented with relative abundances of Rihzobiales, Bacillales, Actinomycetales and Acidobacteriales. 40 families, the Alphaproteobacteria, the Bacilli and the 12 Actinobacteria. 83 orders among which the Rhizobiales are the most abundant followed by Bacillales and the least abundant followed by the Flavobacteriaceae. Of the 28 genera listed, the Bradyrhizobium is the most dominant in Mw3 and Mw4. 25 listed species, Bradyrhizobium, Bacillus, Actinoplanes, and Candidatu coribacter Acidobacterium are the most abundant species. The Shannon indices of Mw3 and Mw4 are equal, the H’max of Mw4 is greater than the H’max of Mw3. The Simpson index of Mw4 is equal to the Simpson index of Mw3, and the Pielou index (J) of Mw4 is less than the R of Mw3, but very close. This study opens interesting perspectives on the knowledge and exploitation of telluric bacteria in several areas of life. 展开更多
关键词 METAGENOMIC Sequencing 16S rRNA Gene SOIL Bacteria
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Modeling and Study Influence of the Temperature Parameter on Corrosion Factors in the Atmospheric Distillation Column of Crude Oil
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作者 Ndiassé Fall Dialo Diop +4 位作者 Sossé Ndiaye Kharouna Talla Haroun Ali Adannou Astou Sarr Aboubaker Chèdikh Beye 《Open Journal of Yangtze Oil and Gas》 CAS 2023年第1期1-10,共10页
Atmospheric distillation is the first step in separating crude oil into by-products. It uses the different boiling temperatures of the components of crude oil to separate them. But crude oil contains a large quantity ... Atmospheric distillation is the first step in separating crude oil into by-products. It uses the different boiling temperatures of the components of crude oil to separate them. But crude oil contains a large quantity of acids and corrosive gases, including sulfur compounds, naphthenic acids, carbon dioxide, oxygen, etc. However, the temperature has an important influence on the aggressiveness of the corrosion factors in the atmospheric distillation column. This paper aims to investigate the role of temperature on corrosive products in the atmospheric distillation column. The results of the developed model show that the temperature increases the corrosion rate in the atmospheric distillation column but above a certain temperature value (about 600 K), it decreases. This illustrates the dual role played by temperature in the study of corrosion within the atmospheric distillation column. 展开更多
关键词 Atmospheric Distillation CORROSION Crude Oil MATERIALS TEMPERATURE
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Endometrial Cancer: Epidemiological, Histological and Therapeutic Aspects in the Gynecology-Obstetrics Department of the Donka National Hospital, CHU of Conakry
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作者 Abdourahamane Diallo Ousmane Balde +3 位作者 Aboubacar M’mah Sylla Ibrahima Conte Aboubacar Fodé Momo Soumah Namory Keita 《Open Journal of Obstetrics and Gynecology》 2023年第9期1507-1515,共9页
Objective: To study the epidemiological, histological and therapeutic characteristics of endometrial cancer in the Gynecology-Obstetrics department of the Donka National Hospital, CHU of Conakry. Methods: We conducted... Objective: To study the epidemiological, histological and therapeutic characteristics of endometrial cancer in the Gynecology-Obstetrics department of the Donka National Hospital, CHU of Conakry. Methods: We conducted a retrospective descriptive study of 86 patients with endometrial cancer treated in the Gynecology-Obstetrics department of the Donka National Hospital from January 1, 2011, to December 31, 2021, based on their medical records. We analysed the epidemiological, histological and therapeutic aspects of the disease. Results: Endometrial cancer accounted for 3.1% of the 2793 gynecological pathology cases registered in the department during the study period, ranking third. The mean age of the patients was 63 ± 5 years. Most of them were uneducated (59.3%), postmenopausal (91.9%), nulliparous (30.2%), obese (65.1%) and hypertensive (77.1%). More than half of the patients (53.4%) were diagnosed at stage I. Endometrioid adenocarcinoma was the predominant histological type (68.6%). Surgery was performed in 96.6% of the patients, and chemotherapy in 14.0%. After a mean follow-up of 15 months, 84.5% of the patients were alive. Conclusion: Endometrial cancer is a common gynecological malignancy in our department. Endometrioid adenocarcinoma is the most frequent histological subtype. Surgery is the main treatment modality. 展开更多
关键词 Cancer ENDOMETRIUM Donka
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RETRACTED:Effect of Long-Term Inorganic Fertilization on Diversity and Abundance of Bacterial and Archaeal Communities at Tillage in Irrigated Rice Field
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作者 Donald Tchouomo Dondjou Henri Fankem +7 位作者 Abdala Gamby Diedhiou Marie-Thérèse Mofini Daouda Mbodj Sarah Pignoly Baboucarr Manneh Laurent Laplaze Aboubacry Kane Victor Désiré Taffouo 《Advances in Bioscience and Biotechnology》 CAS 2023年第1期18-33,共19页
Short Retraction Notice The paper does not meet the standards of "Advances in Bioscience and Biotechnology". This article has been retracted to straighten the academic record. In making this decision the Edi... Short Retraction Notice The paper does not meet the standards of "Advances in Bioscience and Biotechnology". This article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused. Editor guiding this retraction: Prof. Abass Alavi (EiC of ABB). Please see the article page for more details. The full retraction notice in PDF is preceding the original paper which is marked "RETRACTED". 展开更多
关键词 Inorganic Fertilization Soil MICROBIOME TILLAGE Next-Generation Sequencing 16S rRNA Gene V4 Region Senegal
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Influence of the Nature of the Incoming Sludge on the Performance of a Vertical Flow Reed Beds in Dakar-Senegal
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作者 Elhadji Mamadou Sonko Diomaye Dieng +1 位作者 Maïmouna Lo Cheikh Diop 《Journal of Water Resource and Protection》 CAS 2024年第6期429-449,共21页
This work investigates the influence of the type sludge on drainage, plant development, purification performances and biosolids quality. Drainage properties were measured through the frequency of clogging, the percent... This work investigates the influence of the type sludge on drainage, plant development, purification performances and biosolids quality. Drainage properties were measured through the frequency of clogging, the percentage of leachate recovered and the dryness of accumulated sludge. Plant development was measured through the density, the height and the stem diameter. Purification performance was evaluated from the reduction rate. Biosolids quality was measured after 3 months of maturation. The results show that the clogging frequencies were 9.5%;0% and 3.7%;the volume of leachate recovered was 42.2%;20.4% and 24.7% and, the dryness was 33.4%;61.1% and 52.4% for FS-ST, FS-STT and SS respectively. Plants densities were about, with densities 197.1, 171.3 and 178.3 plants/m2 in beds fed respectively with FS-ST, FS-STT and SS. Despite the high removal rates, the concentrations of pollutants in the leachates are above the Senegalese standard NS 05-061 for discharge into the environment. The biosolids are all mature with C/N and NH4+/NO3?ratios lower than 12 and 1 respectively. The biosolids are also rich in organic and mineral elements. The concentrations of Ascaris eggs are higher than the WHO recommendations. These biosolids should be stored for additional time or composted. 展开更多
关键词 Biosolid Quality Dewatering Performance Planted Drying Beds Purification Performance Sludge Type
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Land Use and Gully Dynamics in the Kourfa Watershed, Matankari (Southwest Niger)
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作者 Bachirou Hamadou Younoussa Tahirou Hassane Yaou +4 位作者 Bouba Hassane Abass Kadade Sabou Abdoulkader Moussa Issaka Amadou Abdourhamane Toure Zibo Garba 《Journal of Geographic Information System》 2024年第4期306-320,共15页
The main consequences of climate change in the Sahel have been the metamorphosis of surface conditions. These metamorphoses have resulted in surface degradation, of which silting up of watersheds is the main phenomeno... The main consequences of climate change in the Sahel have been the metamorphosis of surface conditions. These metamorphoses have resulted in surface degradation, of which silting up of watersheds is the main phenomenon. The objective of this study is to assess the environmental trends of the Kourfa pond watershed. The study is based on diachronic mapping with Landsat satellite images and Google Earth images, over the period 1986 to 2021. The study reveals that vegetation (whose rate of regression doubled between 1986 and 2021) has decreased to the benefit of crop areas (whose rate of increase multiplied by 3.61 between 1986 and 2021). Bare soil and encrusted areas have also decreased, with regression rates almost double than those of 1986. In addition, the Kourfa waterholes have experienced two types of changes over 35 years: one progressive between 2011 and 2016 and the other regressive between 2001 and 2021 compared to 1986. The ravine network has been multiplied by a factor of 2.4, with density more than doubled and the connectivity of the hydrographic networks has risen from 2 to 4, with significant bank recession. This dynamic of the Kourfa pond is linked to the high drainage, the increasing complexity of the gully network and the erosion due to the retreat of the watershed banks, all of which contribute to the silting-up of the Kourfa watershed. 展开更多
关键词 Kourfa Pond DYNAMICS WATERSHED Dosso NIGER
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Phytochemical Screening and Assays of Phenolic Compounds in Senna occidentalis L. Leaf and Seed Extracts
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作者 Edmond Antoine Badock Lahat Niang +5 位作者 Abdoulaye Dramé Célestine Nkounkou-Loumpangou Omar Touré Omar Sokhna Nicolas Cyrille Ayessou Mady Cissé 《Food and Nutrition Sciences》 CAS 2024年第7期499-508,共10页
Phytochemical screening and assay of secondary metabolites, crude extracts with distilled water, aqueous methanol, aqueous acetone and aqueous ethanol of leaves and seeds of Senna occidentalis L. were studied in this ... Phytochemical screening and assay of secondary metabolites, crude extracts with distilled water, aqueous methanol, aqueous acetone and aqueous ethanol of leaves and seeds of Senna occidentalis L. were studied in this work. The aim was to verify the distribution of secondary metabolites according to S. occidentalis organs. Four leaf samples from four different localities (South, East, West and Central Senegal) and a mixed sample of seeds were used. Functional molecules such as polyphenols, flavonoids and tannins were then assessed in the leaves and seeds using various standard methods. The results show that Senna occidentalis L. leaf and seed samples display an identical and homogeneous profile, regardless of locality. They contain secondary metabolites and the polyphenol content of extracts from southern, eastern, western and central leaves is: 0.620 - 0.539 - 0.811 - 0.573 g GAE/100 g DM;flavonoids: 0.064 - 0.074 - 0.130 - 0.101 g CE/100 g DM and tannins: 0.326 - 0.264 - 0.269 - 0.494 g TAE/100 g DM. The efficacy of S. occidentalis L. infusions in therapy is thus justified by the presence of these metabolites, whose biological properties are well known. It is then possible to explore isolation of active principles of Senna occidentalis L. leaves and even seeds for producing medicines. 展开更多
关键词 Senna occidentalis L. Total Polyphenols FLAVONOIDS TANNINS
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Stochastic Simulation of Saline Intrusion in the Coastal Aquifer of Saloum, Senegal
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作者 Seyni Ndoye Amadou Sarr +3 位作者 Mathieu Le Coz Cheikh Becaye Gaye Moumtaz Razack Philippe Le Coustumer 《Journal of Environmental Protection》 2024年第8期863-873,共11页
In the Saloum region of central-western Senegal, water needs are essentially met by tapping an underground aquifer associated with the sandy-clay formations of the Continental Terminal, in contact with both the ocean ... In the Saloum region of central-western Senegal, water needs are essentially met by tapping an underground aquifer associated with the sandy-clay formations of the Continental Terminal, in contact with both the ocean to the west and the highly saline waters of the Saloum River to the north. In this estuarine and deltaic zone with its very low relief, the hydraulic loads in the water tables are generally close to zero or even negative, creating a reversal of the natural flow and encouraging saline intrusion into this system, which makes it very vulnerable. This study concerns the implementation of a numerical model of saline intrusion to provide a better understanding of the vulnerability of the water table by analyzing the variability of the freshwater/saltwater interface. The Modflow-2005 code is used to simulate saline intrusion using the SWI2 module, coupled with the GRASS (Geographic Resources Analysis Support System) software under the Linux operating system with the steep interface approach. The probable expansion of the wedge is studied in three scenarios, taking into account its position relative to the bedrock at 1 m, 5 m and 10 m. Simulations carried out under imposed potential and river conditions, based on variations in groundwater reserves using two effective porosity values, 10−1 and 10−2, show that the water table is highly vulnerable in the northwest sector. The probable expansion of the wedge increases as the storage coefficient decreases and is more marked with river conditions in the areas surrounding the Saloum River, reaching 6 km with a probability of 1. The probability of the wedge reaching a certain degree of expansion decreases from 1 to 0.5, and then cancels out as it moves inland. The probable position of the wedge is limited to 500 m or even 1 km depending on the corner around the coast to the southwest and in the southern zone. This modelling, carried out under natural conditions, will be developed further, taking into account climatic parameters and pumping from wells and boreholes. 展开更多
关键词 Saline Intrusion Stochastic Modelling MODFLOW SWI2 Grass GIS AQUIFER Saloum Senegal
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Monte Carlo Simulations of Doping Properties of a Spin-3/2 Ising Nanotube
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作者 Sènan Ida Valérie Hontinfinde Noèl Odjo +2 位作者 Joèl Kple Ansèlme Kpadonou Félix Hontinfinde 《World Journal of Condensed Matter Physics》 CAS 2024年第3期51-65,共15页
The effect of spin-1 impurities doping on the magnetic properties of a spin-3/2 Ising nanotube is investigated using Monte Carlo simulations within the Blume-Emery-Griffiths model in the presence of an external magnet... The effect of spin-1 impurities doping on the magnetic properties of a spin-3/2 Ising nanotube is investigated using Monte Carlo simulations within the Blume-Emery-Griffiths model in the presence of an external magnetic field. The thermal behaviors of the order parameters and different macroscopic instabilities as well as the hysteretic behavior of the material are examined in great detail as a function of the dopant density. It is found that the impurities concentration affects all the system magnetic properties generating for some specific values, compensation points and multi-cycle hysteresis. Doping conditions where the saturation/remanent magnetization and coercive field of the investigated material can be modified for permanent or soft magnets synthesis purpose are discussed. 展开更多
关键词 Doped Ising Nanotube Monte Carlo Simulations Compensation Point Phase Transitions Coercive Field
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Socio-Spatial Dynamics of Land in Southwest Niger: The Case of the Commune of Gothèye
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作者 Maimouna Ali Salamatou Abdourahamane +2 位作者 Abdourhimou Amadou Issoufou Idrissa Soumana Mahamane Ali 《Open Journal of Ecology》 2024年第9期673-682,共10页
In south-west Niger, ecosystems are losing several hectares of their surface area every year due to internally displaced persons and refugees. The commune of Gothèye is not immune to this situation. The aim of th... In south-west Niger, ecosystems are losing several hectares of their surface area every year due to internally displaced persons and refugees. The commune of Gothèye is not immune to this situation. The aim of this research is to assess the impact of displaced persons and refugees on socio-spatio-temporal dynamics of ecosystems using Landsat images. To achieve this, Landsat TM, Landsat ETM+ and OLI 8 satellite images from September and March were used (2010 to 2024). Operations on Envi 5.3, field validation output and finally mapping on ArcGIS were the steps involved. Discrimination is significant, with kappa coefficients of 0.97, 0.96, 0.86 and 0.85. The results obtained indicate a degradation of natural ecosystems, reflected in a change in landscape structure, with a marked reduction in the quantity and quality of ecosystem goods. Analysis of the evolution of land use showed that 31% of the land remained in its initial state (unchanged), 69% underwent modifications, and 11% was converted to cropland. Over these fourteen years, the study area has undergone changes in land use patterns, which have resulted in a modification of landscape structure, with a marked decline in the quantity and quality of ecosystem services. 展开更多
关键词 Dynamics ECOSYSTEM Anthropization Remote Sensing Displaced Persons
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Multi-Elemental Analysis and 2D Image Mapping within Roots, Leaves and Seeds from O. glaberrima Rice Plants Using Micro-PIXE Technique
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作者 Alassane Traore Anna Ndiaye +6 位作者 Christopher Bongani Mtshali Manneh Baboucarr Jean Paul Latyr Faye Daouda Mbodj Kandiaba Traore Tapha Gueye Ababacar Sadikhe Ndao 《World Journal of Nuclear Science and Technology》 CAS 2024年第2期97-106,共10页
Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micr... Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micro-analytical imaging techniques are required to reveal its accumulation and distribution within plant tissues. PIXE studies have been performed to determine different elements in rice plants. The existing microbeam analytical technique at the iThemba LABS will be applied for the 2D image mapping of fresh rice tissues to perform a concentration of low atomic mass elements (such as Al, Si, P, S, Cl, Ca, Ti, Mn, Fe, Cu, Br, Zn and K) with detection limits of typically 1-10 μg/g. Comparison of the distribution of the elements between leaves, root and seed samples using uptake and distribution of elements in particular environmental conditions with potential amount of salt in water have been performed. We are also expecting to indicate metal exclusion as salt tolerance strategies from leaves, root, and seed compartments using matrix correlation between samples and between elements on rice species. 展开更多
关键词 PIXE 2D Mapping Rice Concentration Elemental Analysis
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Three New Hydrogenosuccinate and Succinate Adducts Complexes:Synthesis and Spectroscopic Study
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作者 Boucar Diouf Waly Diallo +3 位作者 Bocar Traoré Daouda Ndoye Cheikh Abdoul Khadir Diop Mamadou Sidibé 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第6期207-210,共4页
One new hydrogenosuccinate and two succinate adduct and complex have been synthesized and studied by infrared,UV-Visible and NMR(Nuclear Magnetic Resonance Spectroscopy)^(119)Sn spectroscopies.The suggested structure ... One new hydrogenosuccinate and two succinate adduct and complex have been synthesized and studied by infrared,UV-Visible and NMR(Nuclear Magnetic Resonance Spectroscopy)^(119)Sn spectroscopies.The suggested structure is discrete,the hydrogenosuccinate behaving as a monodentate ligand or only involved in hydrogen bonding,the environment around the magnesium centre being triangular(compound 3).The succiate anion is a monochelating ligand(compound 1 and 2).In all the suggested structures,when extra hydrogen bonds are considered,supramolecular architectures are obtained(compound 2 and 3). 展开更多
关键词 Discrete structures hydrogen bonds monochelating MONODENTATE triangular or trigonal bipyramidal or tetrahedral environments
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