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Velocity Form Calculations of Generalized Oscillator Strengths for 3s→ (3p, 4p, 5p, 6p) Dipole Transitions of Atomic Sodium in Debye Plasma

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Open Journal of Applied Sciences 2024年第6期14卷 1512-1529页

作者： Louis Gomis Clement Diatta Moustapha Sadibou Tall Ibrahima Gueye Faye Rama Gomis Yande Diouf Mamadou Coulibaly Laboratoire de Physique des Plasmas et de Recherches Interdisciplinaires Departement de Physique Universite Cheikh Anta Diop Dakar Senegal

In this paper, the generalized oscillator strengths (GOSs) of excitations of atomic sodium from ground state to 2p63s0 (3p, 4p, 5p, 6p) states, immersed in Debye plasma, were calculated by using wavefunctions which were obtained numerically from the restricted Hartree-Fock (RHF) equation. This RHF equation employs the local density approach for exchange interactions including plasma Debye screening. Theoretical RHF and random phase approximation with exchange (RPAE) velocity calculations have shown that the GOSs for excitations to 3 s0(3 p,4 p,5 p,6 p)depend on the plasma Debye screening effects, as shown by the reduction in the GOS amplitude with decreasing Debye length λD. The agreement between the present RPAE V results for the transitions 3 s→3 s0(3 p,4 p,5 p)and the length calculations of Martínez-Flores was satisfactory. Correlation effects were found quite to be significant in the vicinity of the maxima of the GOS of the 3 s→3 s0(4 p,5 p,6 p)excitations by using the RPAE V approach. We note the poor influence of many electron correlations on the GOS of (3 s→3 p)transition with the same principal quantum number. Finally, we comment that the RPAE V calculations are useful in investigating electron correlation effects on the transition GOS of atomic sodium planted in Debye plasma. The present velocity results also reveal that the 3 s→3 s0(5p, 6p)transition GOSs tend to be delocalized due to more significant screening effects at Debye lengths λD=20and 30 a.u. for excited subshells 5p and 6p, respectively. We report here novel results of GOS for 3 s→3 s06ptransition obtained from different Debye lengths.

关键词： Plasma Screening Effect Correlation Effect Sodium Atomic Velocity Form GOS Restricted Hatree-Fock Random Phase Approximation with Exchange

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The Essential Oil of Ocimum americanum from Senegal and Gambia as a Source of Methyleugenol for the Control of Bactrocera dorsalis, Fruit Fly

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Journal of Agricultural Chemistry and Environment 2024年第1期13卷 133-141页

作者： Yoro Tine Antonio Alain Coffi Sinzogan Ousmane Ndiaye Cebastiana Sambou Alioune Diallo Ismaila Mbenga Kemo Badji El Hadji Omar Dieng Assa Balayara Jeanne Diatta cheikhouna Gaye Julien Paolini Jean Costa Alassane Wele Saliou Ngom Laboratoire de Chimie Organique et Thérapeutique Faculté de Médecine Pharmacie et Odontologie Université Cheikh Anta Diop Dakar Sénégal Faculte des Sciences Agronomiques Universite d’Abomey Calavi Cotonou Benin Ecole Nationale Supérieure d’Agriculture (ENSA) Université Iba Der Thiam de Thiès Thiès Sénégal Direction de la Protection des Végétaux Rufisque Sénégal Laboratoire de Chimie des Produits Naturels Université de Corse Corte France National Agricultural Research Institute (NARI) Sere Kunda Gambia Institut Sénégalais de Recherches Agricoles (ISRA) Dakar Sénégal

The fruit fly, Bactrocera dorsalis (Diptera: Tephritidae) is one of the most important pests in all mango-producing areas, particularly in West Africa. In Senegal, O. americanum leaves have been used for several years to control this fly. However, to our knowledge, no chemical studies have been carried out. Thus, the aim of this study is to determine the chemical composition of the essential oil of O. americanum leaves collected in Senegal and Gambia. The essential oil obtained by hydrodistillation of these leaves is analyzed by GC/FID and GC/MS. Yields of essential oils from O. americanum leaves are 3.84% and 2.13%, respectively. Analysis of these essential oils by GC/FID and GC/MS allowed the identification of 23 compounds representing almost 100% of the total compositions. These essential oils are mainly dominated by methyleugenol (72.0% and 75.8%, respectively). Other components in significant percent are trans-β-caryophyllene (13.9% and 13.0%, respectively), germacrene D (4.1% and 3.7%, respectively), β-elemene (3.3% and 0.9%, respectively). Due to the high methyleugenol content, this study explains the attractive potential of O. americanum towards B. dorsalis. In perspective, we plan to evaluate the attractive effect of the essential oil and leaf powder of O. americanum against B. dorsalis, a real pest of mango orchards in Senegal.

关键词： Ocimum americanum Essential Oils Methyleugenol Bactrocera dorsalis GC/MS

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Polycyclic Evolution of Paleoproterozoic Rocks in the Southwestern Part of the Mako Group(Eastern Senegal,West Africa)

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International Journal of Geosciences 2014年第7期5卷 739-748页

作者： Papa Moussa Ndiaye Edmond Dioh Famara Diatta Alassane Traore Makhoudia Fall Ousmane Balde Département de Géologie Universite Cheikh Anta DiopDakarSénégal Institut Fondamental d’Afrique Noire Universite Cheikh Anta DiopDakarSénégal Institut de Technologie Nucléaire Appliquée Universite Cheikh Anta DiopDakarSénégal

After an extensional stage giving rise to tholeiitic basalts and gabbros, the south western part of Kédougou Kéniéba Inlier (KKI) was affected by three phases of compressionnal deformation. The first phase (D1) was related to NE-SW stress that led to northeastward thrusting. Early granitoids would be implemented during this tectonic event. The second phase (D2) was due to East-West compressional stress that created combined strike sleep faults: NNW-SSE and NNE-SSW respectively sinistral and dextral. During this phase, some volcanic rocks and gabbros were mylonitized, hydrothermalized and transformed into quartzites. These quartzites were considered as sedimentary rocks in previous studies. Granitic plutons and andesites took place during this tectonic phase. D3 deformation occurred towards the end of the Eburnean orogeny. It would be held in two episodes. In the first episode, WNW-ESE stresses created conjugate shears: sinistral NNW-SSE and dextral NE-SW. In the second episode, stresses moved toward the NE-SW direction and made the resulting brittle structures arranged in NS dextral corridors.

关键词： Paleoproterozoic Eastern Senegal Volcanic-Rocks Polycyclic Deformation Silicification

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An efficient hybrid protection scheme with shared/dedicated backup paths on elastic optical networks

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Digital Communications and Networks 2017年第1期3卷 11-18页

作者： Nogbou G. Anoh Michel Babri Ahmed D. Kora Roger M. Faye Boko Aka Claude Lishou LMI Universite Nangui Abrogoua Abidjan Cote d'Ivoire LARIT Institut National Polytechnique Felix Houphouet Boigny Abidjan Cote d'Ivoire LTI Eeole Superieure Polytechnique Universite Cheikh Anta Diop Dakar Senegal Ecole Superieure Multinationale des Teleommunications Dakar Senegal

Fast recovery and minimum utilization of resources are the two main criteria for determining the protection scheme quality. We address the problem of providing a hybrid protection approach on elastic optical networks under contiguity and continuity of available spectrum constraints. Two main hypotheses are used in this paper for backup paths computation. In the first case, it is assumed that backup paths resources are dedicated. In the second case, the assumption is that backup paths resources are available shared resources. The objective of the study is to minimize spectrum utilization to reduce blocking probability on a network. For this purpose, an efficient survivable Hybrid Protection Lightpath (HybPL) algorithm is proposed for providing shared or dedicated backup path protection based on the efficient energy calculation and resource availability. Traditional First-Fit and Best-Fit schemes are employed to search and assign the available spectrum resources. The simulation results show that HybPL presents better performance in terms of blocking probability, compared with the Minimum Resources Utilization Dedicated Protection (MRU-DP) algorithm which offers better performance than the Dedicated Protection (DP) algorithm.

关键词： Hybrid protection Elastic Optical Networks Backup shared resources Efficient energy cost Minimum resource utilization Modulation format

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Antioxidant and antiglycation properties of two mango(Mangifera indica L.) cultivars from Senegal

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Asian Pacific Journal of Tropical Biomedicine 2018年第3期8卷 137-141页

作者： Samba Fama Ndoye Didier Fraisse Blandine Akendengue Mbaye Diaw Dioum Rokhaya Sylla Gueye cheikh Sall Insa Seck Catherine Felgines Matar Seck Francois Senejoux Laboratory of Organic and Therapeutic Chemistry Faculty of Medicine Pharmacy and Odontology Cheikh Anta Diop University universite Clermont Auvergne INRAUNH Department of Pharmacology and Toxicology Faculty of Medicine and Health Sciences (USS) Laboratory of Chemistry Training and Research Unit of Health Thies University

Objective: To evaluate the total phenolic contents, antioxidant and antiglycation activities of leaves, barks, roots and kernels from two cultivars of Mangifera indica(Anacardiaceae). Methods: Total phenolic contents were determined by using Folin-Ciocalteu's method. The antioxidant activities were assessed by three different protocols including DPPH, oxygen radical absorbance capacity and iron(Ⅱ) chelation assays. In addition, in vitro bovine serum albumin/D-ribose assay was chosen to evaluate the antiglycation properties of the extracts. Results: All the investigated extracts were found to contain high level of total phenols as well as potent antioxidant activities. Kernel extracts showed the highest total phenol contents and DPPH radical scavenging activities whereas higher oxygen radical absorbance capacity values were observed for leave, root and bark extracts. Besides, extracts from leaves, roots and barks from both cultivars exhibited potent inhibitory effects against the formation of advanced glycation end products, with IC_(50) values lower than the standard positive control aminoguanidine. Conclusions: The potent antiglycation and antioxidative activities of these two Mangifera indica cultivars suggest a possible role in targeting aging, diabetic complications and oxidative stress related diseases.

关键词： Mangifera indica Cultivars Polyphenols Antioxidant Antiglycation

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Inventory of Radiation Protection in Hospitals of Level III in Senegal

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Open Journal of Biophysics 2021年第4期11卷 397-406页

作者： Boucar Ndong Sidi Ahmed Dia Mamadou Salif Djigo Herbert Fachinan El Hadji Lamine Bathily Ousseynou diop Kanta Ka Gérard Léra Kelvin Akpo El Hadji Fallou Diouf Louis Auguinstin Diaga Diouf Pape Mady Sy Alphonse Djiboune Gora Mbaye Maguette Diagne Omar Ndoye Mamadou Mbodji Laboratoire de Biophysique Médecine Nucléaire Universite Cheikh Anta Diop Dakar Senegal Service de Médecine du Travail Universite Cheikh Anta Diop Dakar Senegal Faculté de Médecine Université de Parakou Parakou Benin Service de Radiothérapie de Dalal Jamm Dakar Senegal Service de Radiologie de l’Hô pital Aristide Le Dantec Dakar Senegal Laboratoire de Physique Pharmaceutique Universite Cheikh Anta Diop Dakar Senegal Service de Radiothérapie de l’Hô pital Aristide Le Dantec Dakar Senegal

The aim of this study was to evaluate the level of protection of employees who are exposed to radiation in a level III hospital establishment. It was a descriptive cross-sectional survey of six months’ duration, involving eight level III Hospitals (Aristide Le Dantec, Fann, Hoggy, Hear, Abass Ndao, Pikine, Touba, and Thiès) in Senegal. Sixty-one of the one hundred questionnaires were recovered (overall response rate of 61%). The population of the study was mainly female (54.1%). The average age was 38.57 with extremes ranging from 23 to 65 years old. In the places where ionizing radiation sources are handled, only at the Aristide Le Dantec Hospital did we find a “competent person in radiation protection”. This explained the lack of a classification of employees and work areas. Forty out of sixty-one (73.77%) had no knowledge of the basic principles of radiation protection (justification, optimisation, dose limitation) and had not ever taken radiation holidays. For radiovigilance, exposure time limits to ionizing radiation concerned only 29/61 or 47.54% of the study population. The inverse square law of distance was known by only 40 workers, of whom 15 had no compliance. We found the presence of dosifilms in only 7/61 or 11.47% of the workers. On the other hand, the use of lead aprons was well established and concerned 57/61 workers, i.e., 93.44%. In sum, ionizing radiation causes adverse health effects. The absence of a good radiation protection culture in Senegal requires the presence of at least 4 to 5 competent persons in radiation protection for quality training of workers in radiobiology, radiopathology and radiation protection.

关键词： Ionizing Radiation Radiation Protection Workers Senegal

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Spectrofluorimetric Analysis of the Fungicide Carbendazim and Its Metabolite 2-Aminobenzimidazole in Natural Water

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American Journal of Analytical Chemistry 2015年第9期6卷 767-775页

作者： Diene Diegane Thiare Abdourakhmane Khonte Amadou diop Alphonse Mendy Atanasse Coly Francois Delattre Mame Diabou Gaye-Seye Alphonse Tine Laboratoire de Photochimie et d’Analyse(LPA) Faculte des Sciences et TechniquesUniversite Cheikh Anta DiopDakarSenegal Unite de Chimie Environnementale et Interactions sur le Vivant(UCEIV) ULCODunkerqueFrance Laboratoire de Chimie Analytique et Bromatologie(LCAB) Faculte de Medecine de Pharmacie et d’OdontologieUniversite Cheikh Anta DiopDakarSenegal

A spectrofluorimetric method for the direct analysis of carbendazim [methyl 2-benzimidazole carbamate (MBC)] fungicide and its metabolite 2-aminobenzimidazole (2-AB) in natural waters is described. Very low limit of detection (LOD) and limit of quantification (LOQ) values of 0.002 - 0.06 ng/mL and 0.006 - 0.2 ng/mL, respectively, were determined by spectrofluorimetric method with small relative standard deviation (RSD) values < 1%. This spectrofluorimetric method was applied to the determination of MBC and 2-AB residues in natural waters, with satisfactory recovery values of (88.5% - 119.2%).

关键词： Carbendazim 2-Aminobenzimidazole Water Analysis Fluorescence Analytical Method

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Evaluation of Phenolic Content and Antioxidant Activity of Aqueous Extracts of Three Carica papaya Varieties Cultivated in Senegal

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Food and Nutrition Sciences 2019年第3期10卷 276-289页

作者： Aissatou Alioune Gaye Oumar Ibn Khatab Cisse Bou Ndiaye Nicolas Cyrille Ayessou Mady Cisse Codou Mar diop Laboratoire d’Electrochimie et des Procedes Membranaires Centre d’Etudes sur la Securite Alimentaire et des Molecules Fonctionnelles(CESAM)Universite Cheikh Anta DiopDakarSenegal

The aqueous extracts of different parts (old leaves (OL), young leaves (YL), peels (PE) and delipidated seed residues (DS)) of three varieties of papaya are studied. Extraction conditions are optimized: an extraction time of 20 minutes, a temperature of 70°C and a plant material/water mixture of 1% give the best yield of polyphenol. The amount of polyphenols, flavonoids, saponins and proanthocyanins of each aqueous extract was investigated. Antioxidant activities are measured using two different methods (DPPH and ABTS). The delipidated seeds (DS) of V1 have the highest total phenolic content (TPC = 72.56 ± 3.16 mg GAE/g) while they have the lowest total flavonoid content (TFC = 0.22 ± 0.01). With regard to saponins, the PE of V3 is much richer in saponins (194.03 ± 15.78 mg AeE/g) than all the other extracts studied. The OL of V2 and PE of V1 contain the most proanthocyanidins with very similar values of 2.51 ± 0.03 mg CE/g and 2.53 ± 0.34 mg CE/g respectively. The study of the antioxidant activities of the extracts showed a correlation between the amount of polyphenols and IC50. DPPH OL and YL V2, which are rich in polyphenols, have the lowest IC50 of 0.072 mg/ml and 0.080 mg/ml respectively, whereas for ABTS we have PE of V1 that is very rich in polyphenols which has the smallest IC50 value of 0.218 mg/ml.

关键词： Carica papaya Extraction Antioxidant Polyphenols Flavonoids Proanthocyanidins Saponins

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Study of Efficiencies CdTe/CdS Photovoltaic Solar Cell According to Electrical Properties by Scaps Simulation

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Natural Resources 2020年第4期11卷 147-155页

作者： Serigne Massamba Seck Elhadji Ndiouga Ndiaye Modou Fall Stephane Charvet Laboratoire de Physique de la Matiere Condensee(LPMC) Universite de Picardie Jules VerneAmiensFrance Laboratoire de Chimie Physique Organique et d’Analyses Environnementales(LCPOAE) Universite Cheikh Anta DiopDakarSenegal Departement de Physique UFR SATICUniversite Alioune Diop de BambeyBambeySenegal

The photovoltaic performance (efficiency η) of an ITO/CdS/CdTe structure cell is studied in this article according to its electrical properties. The study is carried out by simulation with SCAPS (Solar Cell Capacitance Simulator) whose mathematical model is based on solving the equations of Poisson and continuity of electrons and holes. An electrical conversion efficiency of 23.58% is obtained by optimizing the mobility of the electrons (100 cm2/Vs), that of the holes (25 cm2/Vs), the density of electrons (1015 cm-3), the density of the effective states in the conduction band (7.9 × 1017 cm-3) and the electronic affinity (3.85 eV) of the CdTe absorbent layer.

关键词： Solar Cells Photovoltaic Thin Films CdTe Electron Mobility Charge Carrier Density Simulation SCAPS

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Evaluation of the Aerial Biomass of Three Sahelian Species in the Ferlo (North Senegal): Acacia tortilis(Forsk.) Hayn essp. Raddiana (Savi) Brenan, Acacia senegal(L.) Willd and Balanites aegyptiaca(L.) Del

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Open Journal of Ecology 2021年第2期11卷 183-201页

作者： Daouda Ndiaye Moustapha Bassimbé Sagna Ramata Talla Aly Diallo Jean Luc Peiry 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 Assane Seck University Department of Agroforestry Nema Ziguinchor Senegal Department of Geography Clermont Auvergne University GEOLAB UMR 6042 CNRS Clermont-Ferrand France

In a context of climate change characterized by rising temperatures, increased greenhouse gases and frequent droughts, the Sahel is presented as one of the most vulnerable areas to the adverse effects of climate change. The Sahel is presented as one of the most vulnerable areas to the adverse effects of climate change. The objective of this study is to assess the above-ground biomass and carbon stock of three Sahelian species: Acacia raddiana tortilis (Forsk.) hayne ssp. raddiana (savi) Brenan, Acacia senegal (L.) Willd and Balanites aegyptiaca (L.). The study was carried out in northern Senegal commonly known as Ferlo. Biomasses of the populations of the three target species were first assessed by harvesting the entire epigenetic part of the species and then modelled by correlation using dendrometric parameters measured on each individual of the sample. Two models, mono-specific and multi-species, were used. The results obtained showed that the diameter at breast height (x) and the parameter best correlated to the epigeal biomass (y). The dry biomass of woody plants was 31.4 ± 15.2 kg/tree for B. aegyptiaca, 30.6 ± 13.2 kg/tree for A. senegal and 26.2 ± 11.1 kg/tree for A. raddiana;i.e. carbon equivalents of 14.75 - 14.38 - 12.31 kg/tree respectively. The amount of carbon contained in the above-ground woody biomass is estimated at 4.48 t/ha. The carbon equivalent, atmospheric CO2 is estimated at 16.44 tons of CO2/ha and based on the actual density of Ferlo (108.08 ± 49.79 ind/ha) the sequestered carbon of the area is estimated at 1777.008 tons of CO2. The comparison between the models developed in this study and the multispecific or mono-specific models from the literature showed substantial differences. This study contributes to a better understanding of the contribution of Sahelian woody species to carbon sequestration and the results could be used in

关键词： Acacia Balanites Biomass Allometric Model Ferlo

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