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Reflected BSDEs Driven by L&eacute;vy Processes and Countable Brownian Motions
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作者 Jean-Marc Owo 《Applied Mathematics》 2015年第14期2240-2247,共8页
A new class of reflected backward stochastic differential equations (RBSDEs) driven by Teugels martingales associated with Lévy process and Countable Brownian Motions are investigated. Via approximation, the exis... A new class of reflected backward stochastic differential equations (RBSDEs) driven by Teugels martingales associated with Lévy process and Countable Brownian Motions are investigated. Via approximation, the existence and uniqueness of solution to this kind of RBSDEs are obtained. 展开更多
关键词 Backward DOUBLY Stochastic Differential Equations Lévy PROCESSES Teugels MARTINGALES Countable BROWNIAN Motions
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Microbial Quality and Molecular Identification of Enterotoxigenic Staphylococcus Strains Isolated from Dried, Smoked, and Braised Fish Sold in Ouagadougou Markets
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作者 Arouna Ouédraogo Ganamé Abasse Ouédraogo +3 位作者 Henri Sidabéwindin Ouédraogo François Tchoumbougnang Cheikna Zongo Aly Savadogo 《Advances in Microbiology》 CAS 2024年第1期59-76,共18页
Background: The investigation of toxin genes in strains involved in staphylococcal food poisoning contributes to food safety. The aim of this study was to isolate and identify enterotoxigenic Staphylococcus strains fr... Background: The investigation of toxin genes in strains involved in staphylococcal food poisoning contributes to food safety. The aim of this study was to isolate and identify enterotoxigenic Staphylococcus strains from dried, smoked, and braised fish sold in Ouagadougou markets. Methodology: Staphylococci were isolated using standard microbiology methods. Staphylococcus strains were identified using API Staph kit (Reference # 20500, BioMerieux S.A., Marcy l'Etoile, France). The molecular identification of isolated Staphylococcus aureus strains was specifically confirmed by PCR using the Staur4 and Staur6 primers. The genes encoding enterotoxins, enterotoxin-like toxins, exfoliative toxins, and TSST-1 toxin were detected by multiplex PCR using specific primers from Inquaba Biotec West Africa Ltd, Africa's Genomics Company. Results: The results of the microbiological quality assessment indicated that most of the samples analyzed were found to be of unsatisfactory microbiological quality according to the Staphylococcus aureus microbiological criteria (m = 102). Overall, only 12.55% of samples were satisfactory, while 97.45% were unsatisfactory. The STAPH API gallery allowed the identification of the following species: Staphylococcus aureus, Staphylococcus xylosus, Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus haemolyticus, Staphylococcus lentus, Staphylococcus sciuri and Staphylococcus capitis. Of the 108 Staphylococcus isolates, 81 (75%) showed at least one (1) toxin gene. Among the 21 toxin genes tested in this study, 20 genes were detected in all strains analyzed. The staphylococcal toxin genes detected were present in both Staphylococcus aureus and the other coagulase-negative strains isolated in this study. In addition, these genes are found individually or in association in certain strains. The most frequent genes detected in toxin gene-positive strains were: the tsst-1 gene in 45 isolated strains (41.7%), sei (16/14.8%), seg (13/12%), ser (7/6.5%) sec (6/5.5%), and sea (5/4.6%) for staphylococcal enterotoxins, seln (14/12.9%), selq (8/7.4%), for enterotoxin-like toxin gene and eta (3/2.7%) for exfoliative toxin genes. Conclusion: This study highlighted the pathogenicity of Staphylococcus strains isolated from dried, smoked, and braised fish sold in Ouagadougou markets. Monitoring toxin-producing strains of Staphylococcus is invaluable for better prevention of food poisoning. 展开更多
关键词 FISH Stapholocuccus Toxin Genes OUAGADOUGOU
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Molecular Identification of Mycobacterium Strains Responsible of Bovine Tuberculosis Cases in Bobo-Dioulasso Slaughterhouse, Burkina Faso
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作者 Mariétou Konate Aminata Fofana# +2 位作者 Yacouba Kouadima Aboubacar Sidiki Ouattara Adama Sanou 《Advances in Microbiology》 CAS 2024年第2期105-114,共10页
Bovine tuberculosis (bTB) is an endemic zoonosis significantly affects animal health in Burkina Faso. The primary causative agent is Mycobacterium tuberculosis (M. tuberculosis) complex, mainly M. bovis. Cattle are co... Bovine tuberculosis (bTB) is an endemic zoonosis significantly affects animal health in Burkina Faso. The primary causative agent is Mycobacterium tuberculosis (M. tuberculosis) complex, mainly M. bovis. Cattle are considered as natural reservoir of M. bovis. However, in Burkina Faso, the circulation of these strains remains poorly understood and documented. This study aimed to identify and characterize Mycobacterium strains from suspected carcasses during routine meat inspection at Bobo-Dioulasso refrigerated slaughterhouse. A prospective cross-sectional study was conducted from January 2021 to December 2022 on cases of seizures linked to suspected bovine tuberculosis. Microbiological and molecular analyzes were used for mycobacterial strain isolation and characterization. Out of 50 samples, 24% tested positive by microscopy and 12% by culture. Molecular analysis identified 6 strains of Mycobacteria, exclusively Mycobacterium bovis specifically the subspecies bovis (Mycobacterium bovis subsp bovis). In conclusion, M. bovis subsp bovis is the primary agent responsible for bovine tuberculosis in Bobo-Dioulasso. Continuous monitoring of mycobacterial strains is therefore necessary for the effective control of this pathology in the local cattle population. 展开更多
关键词 Bovine Tuberculosis Mycobacterium bovis Molecular Identification Cattle Population Burkina Faso
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Antiseptic Efficacy of A Soap Made from Biosurfactants Isolated from Bacillus and Lactobacillus against Pathogenic Bacteria
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作者 Frédéric Yannick Okouakoua Christian Aimé Kayath +10 位作者 Nicaise Saturnin Mokémiabeka Varelle Bervanie Ngala Elenga Digne Nedjea N’goma-Mona Ndelani Nkalla Lambi Sandra Paola Elenga Wilson Christ Dieuveil Bayakissa Malanda Rodinet Tsana Junior Patrick Sergy Bissoko1 Moïse Doria Kaya-Ongoto Duchel Jeanedvi Kinavouidi Etienne Nguimbi 《Advances in Microbiology》 CAS 2024年第1期31-58,共28页
The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological technique... The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological techniques (30 Bacillus and 30 Lactobacillus) and the ability to produce biosurfactants was demonstrated by a hydrocarbon emulsification index (E24). The emulsification indexes (E24) varied from 9% to 100% for Bacillus and from 33% to 100% for Lactobacillus as well. The antagonistic assay showed that biosurfactants were able to inhibit the formation of biofilms and growth of pathogens such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Salmonella typhirium, Shigella boydii and Proteus mirabilis. The biosurfactant consortium (BioC) from Bacillus consortium and from Lactobacillus was able to inhibit biofilm formation and the pathogens growth. The BioC was stable to alkaline pH and the temperatures stability of Biosurfactant was ranging from 50°C to 90°C. The soap was made by the cold saponification process using one biosurfactant consortium formulated. This soap has a pH of 10 and showed good cleaning power and good foam stability. Similarly, the soap showed good antiseptic power and disinfection power against all pathogens tested. Handwashing is critical to preventing disease transmission. The persistence of pathogens in waste water was evaluated. The BioS produced showed good disinfection power against all pathogens tested. The valor of reduction on the hands and in the waste water was significantly more than compared to the control soaps used. This soap could be used in the prevention, fighting, and treatment of bacterial and viral infections. 展开更多
关键词 ANTISEPTIC SOAP Biosurfactants BACILLUS LACTOBACILLUS DISINFECTION Pathogens bacteria
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Hepatitis B Surface Antigen and Hepatitis C Virus Antibodies among Drug Users in Burkina Faso
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作者 Sylvie Zida Kadari Cissé +13 位作者 Odette Ky-Zerbo Dinanibè Kambiré Serge Théophile Soubeiga Simon Tiendrebéogo Fatou Sissoko Issa Sory Célestine Ki-Toé Solange Dioma Djeneba Zorom Adama Ouédraogo Cedric Dimitri Axon Hien Mahamoudou Sanou Seni Kouanda Henri Gautier Ouédraogo 《Advances in Microbiology》 CAS 2024年第1期92-104,共13页
Introduction: The epidemiology of both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among drug users (DUs) is little known in West Africa. The study aimed to assess the prevalence of hepatitis B and ... Introduction: The epidemiology of both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among drug users (DUs) is little known in West Africa. The study aimed to assess the prevalence of hepatitis B and C viruses among drug users in Burkina Faso. Methodology: This was a cross-sectional biological and behavioral survey conducted between June and August 2022, among drug users in Ouagadougou and Bobo Dioulasso, the two main cities of Burkina Faso. A respondent-driven sampling (RDS) was used to recruit drug users. Hepatitis B surface antigen was determined using lateral flow rapid test kits and antibodies to hepatitis C virus in serum determined using an Enzyme-Linked Immunosorbent Assay. Data were entered and analyzed using Stata 17 software. Weighted binary logistic regression was used to identify the associated factors of hepatitis B and C infections and a p-value Results: A total of 323 drug users were recruited with 97.5% males. The mean age was 32.7 years old. The inhaled or smoked mode was the most used by drug users. The adjusted hepatitis B and hepatitis C prevalence among study participants were 11.1% and 2.3% respectively. The marital status (p = 0.001), and the nationality (p = 0.011) were significantly associated with hepatitis B infection. The type of drug used was not significantly associated with hepatitis B infection or hepatitis C infection. Conclusion: The prevalence of HBsAg and anti-HCV antibodies among DUs are comparable to those reported in the general population in Burkina Faso. This result suggests that the main routes of contamination by HBV and HCV among DUs are similar to those in the population, and could be explained by the low use of the injectable route by DUs in Burkina Faso. 展开更多
关键词 Drug Users Hepatitis C Hepatitis B PREVALENCE Burkina Faso
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Ecological Wastewater Treatment System in a School Environment Using a Horizontal Flow Biological Reactor: The Case of Typha
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作者 Falilou Coundoul Abdou Khafor Ndiaye Abdoulaye Deme 《Journal of Environmental Protection》 2024年第1期1-12,共12页
The overarching goal of this study is to offer an effective and sustainable solution to the challenges of sanitation in rural and school settings in the northern region of Senegal. The study explores a wastewater trea... The overarching goal of this study is to offer an effective and sustainable solution to the challenges of sanitation in rural and school settings in the northern region of Senegal. The study explores a wastewater treatment approach based on phytoremediation, with a particular focus on the use of horizontally-flowing reed bed filters. Furthermore, it aims to adapt and optimize these systems for the specific needs of Senegal, focusing on wastewater in school environments. Thus, we constructed a horizontally-flowing reed bed filter, planted with Typha, at the Ndiébène Gandiol school in Senegal. We will investigate the efficiency of wastewater treatment by this horizontally-flowing reed bed filter, emphasizing the role of the plant used: Typha. The filter is described in detail, specifying its dimensions, its composition of flint gravel, and the choice of plants, namely Typha. The experimental protocol is detailed, describing the sampling at the entrance and exit of the filter to evaluate water quality. The parameters analyzed include Chemical Oxygen Demand (COD), Biochemical Oxygen Demand over 5 days (BOD5), suspended solids, ammonium, nitrates, phosphates, pH, conductivity, and fecal coliforms. The results indicate a significant improvement in water quality after treatment. COD, BOD5, suspended solids, and fecal coliforms are greatly reduced, thus demonstrating the efficacy of the Typha filter. However, nitrate concentrations remain relatively stable, suggesting room for improvement in their elimination. A perspective of reuse of the treated water is considered, showing that the effluents from the planted filter meet Senegalese and international standards for irrigation. The findings suggest that these waters could be used for a variety of crops, thereby reducing the pressure on freshwater resources. In conclusion, the Typha-based filtration system shows promising results for improving water quality in this region of Senegal. However, adjustments are necessary for more effective nitrate removal. This study paves the way for sustainable use of treated wastewater for irrigation, thus contributing to food security and the preservation of water resources. 展开更多
关键词 Hydraulic Engineering Wastewater Quality Wastewater Treatment Agricultural Irrigation SANITATION ENGINEERING Environment
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The Relation between Mental Workload and Face Temperature in Flight Simulation
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作者 Amin Bonyad Hamdi Ben Abdessalem Claude Frasson 《Journal of Behavioral and Brain Science》 2024年第2期64-92,共29页
In this research, we study the relationship between mental workload and facial temperature of aircraft participants during a simulated takeoff flight. We conducted experiments to comprehend the correlation between wor... In this research, we study the relationship between mental workload and facial temperature of aircraft participants during a simulated takeoff flight. We conducted experiments to comprehend the correlation between work and facial temperature within the flight simulator. The experiment involved a group of 10 participants who played the role of pilots in a simulated A-320 flight. Six different flying scenarios were designed to simulate normal and emergency situations on airplane takeoff that would occur in different levels of mental workload for the participants. The measurements were workload assessment, face temperatures, and heart rate monitoring. Throughout the experiments, we collected a total of 120 instances of takeoffs, together with over 10 hours of time-series data including heart rate, workload, and face thermal images and temperatures. Comparative analysis of EEG data and thermal image types, revealed intriguing findings. The results indicate a notable inverse relationship between workload and facial muscle temperatures, as well as facial landmark points. The results of this study contribute to a deeper understanding of the physiological effects of workload, as well as practical implications for aviation safety and performance. 展开更多
关键词 Mental Workload EEG Thermal Images Flight Simulation AVIATION Face Temperature
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Study of Some Biodemographic Parameters of Caryedon serratus Olivier (Coleoptera: Chrysomelidae) Insect Pest of Tamarind (Tamarindus indica Lin.) Fruit, in Burkina Faso
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作者 Kilo Francine Marina Ki Koï Wenceslas Kam +2 位作者 Emmanuel Kabore Antoine Sanon Zakaria Ilboudo 《Advances in Entomology》 2024年第2期67-77,共11页
The lack of food security leads us to turn to the riches of the forest, namely non-timber forest products (NTFP) and timber forest products (TFP). In Burkina, these products are a source of income for families, improv... The lack of food security leads us to turn to the riches of the forest, namely non-timber forest products (NTFP) and timber forest products (TFP). In Burkina, these products are a source of income for families, improving their living conditions. Tamarindus indica L. that is a NFTP, is widely used in both rural and urban areas. Unfortunately, tamarind is subject to attack by Caryedon serratus. Its biological activity begins on the fruit before the harvest. The aim of our study is to evaluate some biodemographic parameters of the insect pest C. serratus Olivier. First100 healthy T. indica pods were placed in contact with ten pairs of C. serratus for 24 hours. 25 pods, each carrying a maximum of two eggs, were divided into five batches of 5 pods. Then a pair of C. serratus aged less than 24 h was placed in contact with 4 healthy pods for 24 h. Every day, the pair was removed and transferred to another box containing 4 new healthy pods. A total of 20 replicates were performed. The results showed that C. serratus has an average lifespan of 14 days. However, the female (16 days) lived longer and laid an average of 34 eggs during her lifetime. The egg-laying period lasted 14 days, the number of eggs increased until reaching a maximum peak on the 4<sup>th</sup> day. C. serratus has an embryonic development time of 3 days and an emergence rate of 66.63%. However, the weight of males and females differed significantly (p = 0.0108). We found an intrinsic rate of natural increase of 0.12 and a population doubling time was 5.68 days. These results have enabled us to gain a better understanding of its development cycle and its capacity for regeneration. This allows us to implement control strategies for better stock protection. 展开更多
关键词 Biodemographic Parameters STOCK Caryedon serratus Tamarindus indica
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Stationary Flow of Blood in a Rigid Vessel in the Presence of an External Magnetic Field: Considerations about the Forces and Wall Shear Stresses 被引量:3
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作者 Agnè s Drochon +2 位作者 Vincent Robin Odette Fokapu Dima Abi-Abdallah Rodriguez 《Applied Mathematics》 2016年第2期130-136,共7页
The magnetohydrodynamics laws govern the motion of a conducting fluid, such as blood, in an externally applied static magnetic field B0. When an artery is exposed to a magnetic field, the blood charged particles are d... The magnetohydrodynamics laws govern the motion of a conducting fluid, such as blood, in an externally applied static magnetic field B0. When an artery is exposed to a magnetic field, the blood charged particles are deviated by the Lorentz force thus inducing electrical currents and voltages along the vessel walls and in the neighboring tissues. Such a situation may occur in several biomedical applications: magnetic resonance imaging (MRI), magnetic drug transport and targeting, tissue engineering… In this paper, we consider the steady unidirectional blood flow in a straight circular rigid vessel with non-conducting walls, in the presence of an exterior static magnetic field. The exact solution of Gold (1962) (with the induced fields not neglected) is revisited. It is shown that the integration over a cross section of the vessel of the longitudinal projection of the Lorentz force is zero, and that this result is related to the existence of current return paths, whose contributions compensate each other over the section. It is also demonstrated that the classical definition of the shear stresses cannot apply in this situation of magnetohydrodynamic flow, because, due to the existence of the Lorentz force, the axisymmetry is broken. 展开更多
关键词 Magnetohydrodynamic Flow of Blood Wall Shear Stresses Magnetic Field in Biomedical Applications
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Minority Carrier Diffusion Coefficient <i>D</i>*(<i>B,T</i>): Study in Temperature on a Silicon Solar Cell under Magnetic Field 被引量:2
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作者 Richard Mane Ibrahima Ly +6 位作者 Mamadou Wade Ibrahima Datta Marcel S. Douf Youssou Traore Mor Ndiaye Seni Tamba Grégoire Sissoko 《Energy and Power Engineering》 2017年第1期1-10,共10页
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 attenti... 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. 展开更多
关键词 Solar cell DIFFUSION COEFFICIENT TEMPERATURE Magnetic Field
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Phenotypic and Molecular Characterization of Staphylococcaceae and Enterobacteriaceae Species Isolated from Smoked, Dried, and Braised Fish Marketed in Ouagadougou 被引量:1
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作者 Arouna Ouédraogo Roukiatou Traoré +6 位作者 Ganamé Abasse Ouédraogo Namwin Siourimè Somda Hama Cissé Stephen Mbigha Ghogomu Francois Tchoumbougnang Cheikna Zongo Aly Savadogo 《Advances in Microbiology》 CAS 2023年第1期48-75,共28页
Background: To preserve its nutritional properties, fish must have good sanitary quality. The objective of this study was to investigate some pathogens contaminating smoked, dried, and braised fish marketed in Ouagado... Background: To preserve its nutritional properties, fish must have good sanitary quality. The objective of this study was to investigate some pathogens contaminating smoked, dried, and braised fish marketed in Ouagadougou. Methodology: Potential pathogens of Enterobacteriaceae and Staphylococcus were screened in eight (8) species of processed fish. The investigation of the germs was carried out following the normative methods of microbiology. The identities of the strains were determined by API 20 E (BioMerieux S.A., France) and API STAPH (BioMerieux S.A., France) kits for Enterobacteriaceae and Staphylococcus species respectively. The uidA gene profile in Escherichia coli isolates was determined by simplex PCR. The identity of Staphylococcus aureus was confirmed by amplification of specific 23S rDNA regions and nuc gene profile with PCR. Results: A total of 235 fish samples were analyzed. A diversity of Enterobacteriaceae and Staphylococcus was detected. Twenty species of Enterobacteriaceae were identified among which, the most frequent were Escherichia coli, Salmonella sp, Raoultella ornithinolytica and Serratia odorifera, respectively in 22.6%, 4.3%, 28.9%, 17.4% of the samples analyzed. However, eleven species of Staphylococcus were identified among which, Staphylococcus xylosus, Staphylococcus aureus, Staphylococcus lugdunensis, and Staphylococcus sciuri were the most frequent with respective percentages of 47.7%, 23.4%, 12.8% and 10.6% of samples. For all the samples, the species frequently isolated were: Raoultella ornithinolytica, Escherichia coli, Serratia odorifera, Staphylococcus aureus, Staphylococcus xylosus, and Staphylococcus lugdunensis. The uidA gene specific to Escherichia coli was detected in 82.85% of strains (29/35). Amplification of the specific 23S rDNA region using staur primers was observed in 98% (49/50) of the isolated Staphylococcus aureus strains and the nuc gene was detected in 86% of Staphylococcus aureus strains. Conclusion: The isolated bacteria are potential pathogens involved in foodborne illnesses and intoxications. Effective sanitary safety systems must be implemented to guarantee the sanitary quality of fish supplied to consumers. 展开更多
关键词 Fish Contamination ENTEROBACTERIACEAE Staphylococcus Phenotypic and Molecular Characterization OUAGADOUGOU
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Solar Controller with Automatic Search Technology for the Maximum Power Point with Autonomy Display 被引量:1
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作者 Mamadou Sall Ousmane Sow +4 位作者 Sega Gueye Gora Diop Lemrabott Habiboullah Mamadou Wade Gregoire Sissoko 《Energy and Power Engineering》 CAS 2022年第9期509-522,共14页
In our work, we have been interested in conducting technological research on the use of photovoltaic energy for lighting. In fact, we have produced a stand-alone photovoltaic system with automatic search for the maxim... In our work, we have been interested in conducting technological research on the use of photovoltaic energy for lighting. In fact, we have produced a stand-alone photovoltaic system with automatic search for the maximum power point, consisting of a photovoltaic module, a solar regulator, a storage battery and a digital control by microcontroller. The solar field is connected to the input of the regulator and the battery to its output. When the battery voltage is lower than the regulation voltage, the controller operates the photovoltaic generator at maximum power Pmpp and transfers this power to the output. In addition to the protection function, this regulator ensures tracking of the maximum power point (MPPT) and allows the photovoltaic generator to deliver its power whatever the variation of climatic conditions (sunshine and temperature). The main role of the solar regulator is the continuous monitoring of the state of charge of the battery to ensure its protection against overcharging and excessive discharging, the coupling and decoupling of the user as well as its maintenance. The principle of operation is based on controlling a DC-DC converter by a rectangular “PWM” signal generated by a PIC16F874 microcontroller which also controls the entire system. The results of simulation after realization were presented to illustrate the operation of the regulator by curves. 展开更多
关键词 Index Terms-Battery Charge/Discharge REGULATOR PIC16FC874
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Recent Vegetation Cover Dynamics and Climatic Parameters Evolution Study in the Great Green Wall of Senegal 被引量:1
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作者 Bi Tra Olivier Gore Angora Aman +1 位作者 Yves Kouadio Ody-Marc Duclos 《Journal of Environmental Protection》 CAS 2023年第4期254-284,共31页
The drought recorded in 1970s and 1980s, particularly in the Sahara and Sahel region has greatly affected the population as well as the economies and the eco-systems of this area. In 2007, the African Union launched a... The drought recorded in 1970s and 1980s, particularly in the Sahara and Sahel region has greatly affected the population as well as the economies and the eco-systems of this area. In 2007, the African Union launched a Pan-African program, the Great Green Wall for the Sahara, the Sahel Initiative (GGWSSI) to reverse land degradation and desertification by planting a wall of trees stretching from Dakar to Djibouti. The objective is to improve food security, and support local people to adapt to climate change. This paper aims to evaluate the impacts of the reforestation program in Senegal, fifteen years after it was launched. This study uses a time series of satellite-derived vegetation cover and climatic parameters data to analyze the sustainability of these interventions. Change detection approaches were applied to identify and characterize the drives of the eventual changes. A comparative analysis of reforestation on climatic parameters was explored through the temporal analysis of the vegetation index over the periods 2000-2008 and 2009-2020. An increase in vegetation activity was noted through the NDVI at the interannual (+2% to +8%) and seasonal (+1.5% to 7% for the wet season and 1% to 4% for the dry season) scale and a positive and significant evolution is noted on the trace of the GGW. Also, the period 2009-2020 recorded an increase in rainfall of 2% to 8% of the average value 2000-2020 and 4% to 8% of the rainy season. Soil moisture is the climatic parameter that has increased the most, with an increase of 25% to 54% of the 2000-2020 average, i.e. between 20 mm and 70 mm more. This study shows a significant improvement in the relationship between NDVI and climate parameters after the different reforestation actions of the GGW. 展开更多
关键词 Great Green Wall of Senegal Vegetation Index PRECIPITATION Soil Moisture
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Prediction of Swelling Kinetics of Expansive Soils of Rufisque (Senegal, West Africa) 被引量:1
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作者 Papa Sanou Faye Issa Ndoye +3 位作者 Mapathé Ndiaye Abib Tall Ibrahima Khalil Cissé Jean Pierre Magnan 《Open Journal of Civil Engineering》 2017年第2期267-281,共15页
The disorders caused by the swelling of the soil on the structures have been observed for several years in the city of Rufisque. This article presents the results of the study of swelling kinetics of expansive soils i... The disorders caused by the swelling of the soil on the structures have been observed for several years in the city of Rufisque. This article presents the results of the study of swelling kinetics of expansive soils in Rufisque and their prediction based on the hyperbolic rule. The odometer is used as an instrument for measuring swelling and the tests are carried out on some intact samples at their sampling water content. The present study shows that in Rufisque the most swelling layer is marl. The results show two phases of development. The first phase is very fast and represents 77% of the final deformation and the second one is slower. The prediction of the issue by the hyperbolic rule shows that it underestimates the first phase but gives a good prediction of the second phase of the swelling rate. There is a good correlation between the final swelling rates. However, the model gives a bad approximation of the half-swelling time. 展开更多
关键词 MARLS MARLS Clays Clays KINETIC SWELLING Expansive Soils HYPERBOLIC Rule Rufisque
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Functional Weak Laws for the Weighted Mean Losses or Gains and Applications
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作者 Gane Samb Lo Serigne Touba Sall Pape Djiby Mergane 《Applied Mathematics》 2015年第5期847-863,共17页
In this paper, we show that many risk measures arising in Actuarial Sciences, Finance, Medicine, Welfare analysis, etc. are gathered in classes of Weighted Mean Loss or Gain (WMLG) statistics. Some of them are Upper T... In this paper, we show that many risk measures arising in Actuarial Sciences, Finance, Medicine, Welfare analysis, etc. are gathered in classes of Weighted Mean Loss or Gain (WMLG) statistics. Some of them are Upper Threshold Based (UTH) or Lower Threshold Based (LTH). These statistics may be time-dependent when the scene is monitored in the time and depend on specific functions w and d. This paper provides time-dependent and uniformly functional weak asymptotic laws that allow temporal and spatial studies of the risk as well as comparison among statistics in terms of dependence and mutual influence. The results are particularized for usual statistics like the Kakwani and Shorrocks ones that are mainly used in welfare analysis. Data-driven applications based on pseudo-panel data are provided. 展开更多
关键词 Empirical PROCESS Time Dependent PROCESS WEAK Theory Risk Measures POVERTY Index Loss Function Economic WELFARE
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Contribution to the Modeling of a Solar Adsorption Refrigerator under the Climatic Conditions of Burkina Faso
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作者 Guy Christian Tubreoumya Alfa Oumar Dissa +7 位作者 Eloi Salmwendé Tiendrebeogo Xavier Chesneau Aboubacar Compaoré Kayaba Haro Charles Didace Konseibo Belkacem Zeghmati Jean Koulidiati 《Energy and Power Engineering》 2017年第2期119-135,共17页
This work concerns a dynamic modeling and a numerical simulation of the operation of an adsorption solar refrigeration system using the zeolite-water couple. For this, a mathematical model representing the evolution o... This work concerns a dynamic modeling and a numerical simulation of the operation of an adsorption solar refrigeration system using the zeolite-water couple. For this, a mathematical model representing the evolution of heat and mass transfer at each component of the solar adsorption refrigerator has been developed. We have adopted the Dubinin-Astakhov model for the adsorption kinetics of the zeolite/water pair. This model allows to describe the phenomenon of adsorption and to calculate the rate of adsorbate (water) in the zeolite (adsorbent) as a function of the temperature and the pressure. The equations governing the operation of the solar adsorption refrigerator, deduced from the thermal and mass balances established at the collector adsorber, condenser and evaporator components, were solved by an implicit finite difference scheme and Gauss Seidel’s iterative method. We have validated the model established by applying it to the model of Allouhi et al. 2014. We analyzed the influence of the adsorbate/adsorbent couples, the solar flux, the ambient temperature on the adsorption and desorption process. The temperature profiles obtained representing the temperature evolution of the glass, the absorbent plate, the zeolite-water mixture, the condenser, the evaporator, as well as the pressure and the adsorbed mass allowed us to evaluate the performance of the solar adsorption refrigerator. SCOP is higher the higher the solar flux captured by the collector-adsorber. 展开更多
关键词 SOLAR REFRIGERATION Simulation ADSORPTION Zeolite/Water Burkina Faso
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Characterization of Two Different Stumps of <i>Spirulina platensis</i>Drying: Assessment of Water Transport Coefficient
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作者 Eloi Salmwendé Tiendrebeogo +6 位作者 Alfa Oumar Dissa Fabien Cherblanc Issakha Youm Jean-Claude Bé net Aboubacar Compaoré Jean Koulidiati 《Food and Nutrition Sciences》 2015年第15期1437-1449,共13页
The sorption behaviour and water transport mechanisms inside Spirulina platensis samples were experimentally analysed during isothermal drying at 25℃ and 50℃. Two different products grown in semi-industrial farms fr... The sorption behaviour and water transport mechanisms inside Spirulina platensis samples were experimentally analysed during isothermal drying at 25℃ and 50℃. Two different products grown in semi-industrial farms from Burkina Faso and France with initial water contents respectively of the range from 2.73 kg w /kg dm to 3.12 kg w /kg dm were characterized. A novel procedure has been developed to determine the water content profiles inside samples during isothermal drying. At both temperatures, experimental results underlined that the physical properties of Spirulina are not sensitive to the geographical origin, Burkina-Faso or France. To keep Spirulina at an water activity below 0.6 in order to preserve it from micro-organisms development, sorption isotherm curves show that a sufficient requirement is to lower the water content until an upper limit of w = 0.075 db. The evolution of water transport coefficient as a function of water content highlights a monotonous exponential dependence with a transport coefficient ranging from 1.70 × 10–10 to 94 × 10–10 m2/s. The contribution of solid phase shrinkage to the transport of water is negligible for the last drying steps. 展开更多
关键词 i>Spirulina PLATENSIS Isotherm Desorption Stump WATER Content WATER Transport COEFFICIENT
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Fighting Poor Quality Medicines: Development, Transfer and Validation of Generic HPLC Methods for Analyzing Two WHO Recommended Antimalarial Tablets
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作者 Jérémie Kindenge Mbinze Achille Yemoa +7 位作者 Pierre Lebrun Pierre-Yves Sacré Védaste Habyalimana Nicodème Kalenda André Bigot Eugène Atindehou Philippe Hubert Roland Djang’eing’a Marini 《American Journal of Analytical Chemistry》 2015年第2期127-144,共18页
As serious but neglected public health problems, poor quality medicines, i.e. for antimalarial medicines, urged to be fought. One of the approaches is to consider the analytical chemistry and separative techniques. In... As serious but neglected public health problems, poor quality medicines, i.e. for antimalarial medicines, urged to be fought. One of the approaches is to consider the analytical chemistry and separative techniques. In this study, a generic liquid chromatographic method was firstly developed for the purpose of screening 8 antimalarial active ingredients, namely amodiaquine (AQ), piperaquine (PPQ), sulfalene (SL), pyrimethamine (PM), lumefantrine (LF), artesunate (AS), artemether (AM) and dihydroartemisinine (DHA) by applying DoE/DS optimization strategy. Since the method was not totally satisfying in terms of peak separation, further experiments were undergone applying the same development strategy while splitting the 8 ingredients into five groups. Excellent prediction was observed prior to correlation between retention times of predicted and observed separation conditions. Then, a successful geometric transfer was realized to reduce the analysis time focusing on the simultaneous quantification of two WHO’s recommended ACTs in anti-malarial fixed-dose combination (AM-LF and AS-AQ) in tablets. The optimal separation was achieved using an isocratic elution of methanol-ammonium formate buffer (pH 2.8;10 mM) (82.5:17.5, v/v) at 0.6 ml/min through a C18 column (100 mm × 3.5 mm, 3.5 μm) thermostated at 25℃. After a successful validation stage based on the total error approach, the method was applied to determine the content of AM/LF or AS/AQ in seven brands of antimalarial tablets currently marketed in West, Central and East Africa. Satisfying results were obtained compared to the claimed contents. 展开更多
关键词 ANTIMALARIAL ACT Simultaneous Determination POOR QUALITY Substances DESIGN of Experiments DESIGN Space Method TRANSFER Accuracy Profile
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Anti-Sickle Cell Anemia and Bacterial Inhibitory Effects of <i>Uvariodendron molundense</i>(Diels) R.E.Fr. (Annonaceae) from Ubangi River Basin, DR Congo
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作者 Koto-Te-Nyiwa Ngbolua Dorotheé +7 位作者 D. Tshilanda Djolu R. Djoza Clarisse M. Falanga Masengo C. Ashande Damien S. T. Tshibangu Jeff B. Iteku Virima Mudogo Pius T. Mpiana 《Journal of Biosciences and Medicines》 2017年第3期71-84,共14页
The present study was carried out with the aim of evaluating the chemical composition and bioactivity of Uvariodendron molundense against Sickle cell disease and associated pathogenic bacteria agents. The antisickling... The present study was carried out with the aim of evaluating the chemical composition and bioactivity of Uvariodendron molundense against Sickle cell disease and associated pathogenic bacteria agents. The antisickling and antibacterial activities were assessed using Emmel and micro-dilution methods respectively. The results revealed that the leaves and stem bark of U. molundense contains various secondary metabolites such as total phenols, flavonoids, anthocyanins, tannins, quinones, saponins, alkaloids, steroids, terpenoids and leuco-anthocyanins. The n-hexane (non-polar solvent) extract displayed poor yield (0.66) than the extracts obtained in the polar solvents which have a high yield (Methanol: 1.68, Ethanol: 1.46 and Ethyl acetate: 1.40). These results indicate that the abundant secondary metabolites/compounds in this plant species are those which pass easily through the polar solvents (methanol, ethanol and ethyl acetate). This is the case of phytomarkers like flavonoids and tannins (which are most concentrated in methanol) and anthocyanins which are concentrated in ethyl acetate. The extraction yield of organic/triterpenoic acids (betulinic acid rich extract) was 1.70%. All tested extracts displayed antisickling activity. At 100 μg/mL, the rates of normalization were 89% for organic extract (ED50 = 0.391 μg/ml) and 82% for anthocyanins extract (ED50 = 0.659 μg/mL). The antibacterial activity of tested extracts was very good toward Staphyloccocus areus (CMI ≤ 31.25 μg/mL) while, for Escherichia coli, only the organic extract exhibit interesting activity (CMI = 31.25 μg/mL). This study validates for the first time the in vitro antisickling activity of U. molundense. The bioactivity profiles of organic acids extract from the studied plant material indicate that they constitute promising fraction to be further investigated phytochemically for the discovery of new lead compounds for pharmaceutical application. 展开更多
关键词 SICKLE Cell Disease Traditional Foods NUTRACEUTICALS Anthocyanins Triterpenic Acids
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2D Modeling of Solar Cell Radial Junction: Study of Carriers Charge Density and Photocurrent Density in Static Mode under Monochromatic Illumination
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作者 Moussa Ouédraogo Raguilignaba Sam +2 位作者 Alain Diasso Bernard Zouma François Zougmoré 《Energy and Power Engineering》 2020年第10期568-577,共10页
A theoretical study of a polysilicon solar cell with a radial junction in static regime under monochromatic illumination is presented in this paper. The junction radial solar cell geometry is illustrated and described... A theoretical study of a polysilicon solar cell with a radial junction in static regime under monochromatic illumination is presented in this paper. The junction radial solar cell geometry is illustrated and described. The carriers’ diffusion equation is established and solved under quasi-neutral base assumption with boundaries conditions and Bessel equations. New analytical expressions of electrons and holes density and photocurrent are found. The wavelength and structural parameters (base radius, emitter thickness) influences on charge carriers density and photocurrent are shown and examined. 展开更多
关键词 Electrons Density Holes Density Holes Photocurrent Radial Junction
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