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Genomic Profile of SARS-COV-2 Associated with COVID-19 Outbreaks in N’Djamena, Chad

Advances in Bioscience and Biotechnology 2024年第7期15卷 432-442页

作者： Mathieu Hota Henry Yandai Fissou Dezoumbe Koutaya Djallaye Djimtoïbaye Mahamat Moussa Ali cole Doctorale sciences Techniques et Environnement Universit de NDjamena NDjamena Tchad Institut de Recherche en Elevage pour le Dveloppement NDjamena Tchad Laboratoire des Grandes pidmies Tropicales du CHU le Bon Samaritain NDjamena Tchad Facult des sciences de la Sant Humaine (FSSH) Universit de NDjamena NDjamena Tchad

Background: SARS-CoV-2 has circulated worldwide with dramatic consequences. In Chad, we have no data reported of variants. The aim of this study was to identify the SARS-CoV-2 variants that circulated during the epidemic from 2020 to 2021. Methods: This is a cross-sectional, descriptive study carried out between 2020 and 2021. Samples from patients with suspected COVID-19 were tested in five laboratories in N’Djamena. One hundred quality samples of the positives were sequenced in Kinshasa using Oxford nanopore technologies minion and the Protocol Midnight SARS-CoV2. Data were processed using Excel version 16 software. Results: Of the 100 samples sequenced, 77 (77%) produced sequences, 23 (23%) did not. The genomic profiles were wild-type Wuhan and minor mutations (19A, 19B (A), 20A (B.1, B.2), 20B (AV.1), 20D (B.1.1.1 /C.36), 20C), variant of concern Alpha (20I), variant of concern Delta (21A/J), variant of interest eta (21D), variant of concern Omicron (21K) and unclassified variant under surveillance (B.1.640). Of these variants, the maximums were detected in patients aged 26 - 35 with 30.26% and 25.26% in 36 - 45. However, 24.67% were in travelers and 75.32% in residents, 35.06% in those vaccinated against COVID-19 and 62.33% in non-vaccinates. The estimated case-fatality rate was 2.44% (107/4374). Conclusion: This work has provided preliminary data on COVID-19 and SARS-CoV-2 variants circulating during the 2020-2021 epidemics in Chad.

关键词： COVID-19 SARS-CoV-2 Genomic Profile Variant Chad

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3D hydrodynamics involving multiple eccentric impellers in unbaffled cylindrical tank

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Chinese Journal of Chemical Engineering 2016年第5期24卷 572-580页

作者： Houari Ameur Institut des sciences et technologies Centre Universitaire Salhi Ahmed CUN-SA

In this paper, the numerical predictions of 3D hydrodynamics and power consumption in a vessel stirred by mul- tiple eccentrically located impellers are presented. The vessel is a fiat-bottomed cylindrical one equipped with six-curved bladed impellers. Aqueous solutions of xanthan gum are used, which have a shear thinning behavior with yield stress. The influence of several parameters on the mixing efficiency has been investigated, namely： the stirring rate, fluid theology, impeller number and impeller clearance from the tank bottom. Our predicted results are compared with other experimental data and a satisfactory agreement is found.

关键词： Computational fluid dynamics Mixing Non-Newtonian fluids Laminar flow Eccentric impeller

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Genetic Enhancement of Indigenous Cowpea with Gamma-Ray Induced Trait Variation

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American Journal of Plant sciences 2024年第8期15卷 651-676页

作者： Mathurin Tiergnin Dabiré Minimassom Philippe Nikiéma Djibril Yonli Safiatou Sanna Wossoguim Josué Gouba Siébou Palé Hamidou Traoré Joseph T. B. Batieno Varra Prasad Zacharia Stewart Jan B. Middendorf Abhishek Rathore Anupama J. Hingane Unit de Formation et de Recherches en sciences et technologies Dpartement des Sciences de la Vie et de la Terre Universit Norbert ZONGO Koudougou Burkina Faso Institut de lEnvironnement et de Recherches Agricoles (INERA) Ouagadougou Burkina Faso Department of Agronomy Kansas State University Manhattan USA Center for Agriculture-Led Growth Bureau for Resilience and Food Security United States Agency for International Development United States Agency for International Development Washington DC USA International Maize and Wheat Improvement Center (CIMMYT) ICRISAT Campus Patancheru India Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture Department of Nuclear sciences and Applications Plant Breeding and Genetics Laboratory International Atomic Energy Agency (IAEA) Seibersdorf Vienna Austria

Production of cowpea (Vigna unguiculata (L.) Walp.), a staple legume crop in Sub-Saharan Africa, faces challenges due to biotic and abiotic constraints. Induced mutagenesis was deployed to create genetic variation in two cowpea varieties (KVX396-4-5-2D and Moussa local). The radio-sensitivity tests led to determe the lethal dose 50 (LD50) corresponding to 230 Gy and 220 Gy for KVX396-4-5-2D and Moussa local varieties, respectively. Dried seeds (M0) of each variety were gamma-ray irradiated with LD50 − 50, LD50 and LD50 + 50. M1 seeds were advanced to generate M2, M3 and M4 mutants using the single-seed-descent method. M4 mutant lines were evaluated in rain-fed conditions using a randomized complete block design to assess phenotypic differences. Data on seven qualitative and eleven quantitative traits were collected. The results indicated that the mutation induced variability in three qualitative traits: in KVX 396-4-5-2D mutant lines, with flower and seed color frequencies at 2.61% and 0.56% respectively, and pod dehiscence at a frequency of 0.24%. While in Moussa local mutants, a pod color changed at a frequency of 17%. ANOVA results revealed significant differences between mutants of both varieties for all quantitative traits, including photosynthetic parameters. Positive correlations were observed between leaf diameter and 100-seed weight, and between branch number and 100-seed weight. Hierarchical clustering revealed three clusters among KVX 396-4-5-2D mutants and six clusters among Moussa local mutants. Early maturity and high foliage were induced traits in Cluster 3 of KVX 396-4-5-2D mutants while high hundred-seed weight was induced in Cluster 6 of Moussa local mutants.

关键词： Cowpea Mutagenesis Gamma Rays Radio-Sensitivity Phenotyping

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Exact Solution of D-Dimensional Klein-Gordon Oscillator with Minimal Length

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Communications in Theoretical Physics 2010年第2期53卷 231-236页

作者： Y.Chargui L.Chetouani A.Trabelsi Unit de Recherche de Physique Nuclaire et des Hautes Energies Facult des Sciences de Tunis Dpartement de Physique Thorique Institut de Physique Universit de Constantine Route Ain El Bey Unite de Recherche de Physique Nucleaire et des Hautes Energies Faculte des Sciences de Tunis Centre National des sciences et technologies Nuclaires

Specific modifications of the usual canonical commutation relations between position and momentumoperators have been proposed in the literature in order to implement the idea of the existence of a minimal observablelength. Here, we study a consequence of this proposal in relativistic quantum mechanics by solving in the momentumspace representation the Klein-Gordon oscillator in arbitrary dimensions. The exact bound states spectrum and thecorresponding momentum space wave function are obtained. Following Chang et al. (Phys. Rev. D 65 (2002) 125027),we discuss constraint that can be placed on the minimal length by measuring the energy levels of an electron in a penningtrap.

关键词： Klein-Gordon oscillator minimal length energy spectrum

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Effects of acid treatments on Moroccan Tarfaya oil shale and pyrolysis of oil shale and their kerogen

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燃料化学学报 2009年第6期37卷 659-667页

作者： ABOULKAS A El HARFI K Laboratoire de Recherche sur la Reactivites des Materiaux et IOptimisation des Procedes 《REMATOP》 Departement de chimie Faculte des Sciences Semlalia Universite Cadi Ayyad BP 2390 40001 Marrakech Maroc Laboratoire lnterdisciplinaire de Recherche en sciences et Techniques Faculte polydisciplinaire de Beni-Mellal Universite Sultan Moulay Slimane BP 592 23000 Beni-Mellal Maroc

In this study,the kerogen of oil shale from Moroccan Tarfaya deposits was isolated and the changes in the initial organic matter during the removal of the mineral matrix were *** extraction of the oil shale increases the intensity of the peaks in the X-ray *** spectra and X-ray diffractograms reveal the presence of mineral,calcite,quartz,kaolinite,and pyrite in the mineral matrix of the oil *** and hydrofluoric acids dissolution do not alter the organic *** nonisothermal weight loss measurements indicate that thermal decomposition of the isolated kerogen can be described by first-order reaction.A single kinetic expression is valid over the temperature range of kerogen pyrolysis between 433K and ***,the results indicate that the removal of mineral matter causes a decrease in the activation energies of the pyrolysis reactions of oil shale.

关键词：页岩矿物方解石氢氟酸

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Nonlinear continuous bi-inductance electrical line with dissipative elements:Dynamics of the low frequency modulated waves

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Chinese Physics B 2020年第4期29卷 179-189页

作者： S M Ngounou F B Pelap Unite de Recherche de Mecanique et de Modelisation des Systèmes Physiques(UR-2 MSP) Faculte des SciencesUniversite de DschangBP 69 DschangCameroun Unite de Recherche de Matiere Condensee d'Electronique et de Traitement du Signal(UR-MACetS) Faculte des SciencesUniversite de DschangBP 67 DschangCameroun

The dynamics of modulated waves in a nonlinear bi-inductance transmission line with dissipative elements are *** show the existence of two frequency modes and carry out intensive investigations on the low frequency *** to the multiple scales method,the behavior of these waves is investigated and the dissipative effects are *** appears that the dissipation coefficient increases with the carrier wave *** the continuous approximation,we derive that the propagation of these waves is governed by the complex Ginzburg-Landau equation instead of the Korteweg-de-Vries equation as previously *** studies of the dynamics of plane waves in the line reveal the existence of three additional regions in the dispersion curve where the modulational phenomenon is *** the low frequency mode,we demonstrate that the network allows the propagation of dark and bright *** findings are in perfect agreement with the analytical predictions.

关键词： dissipative bi-inductance network low frequency mode continuous approximation complex Ginzburg-Landau equation

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Improvement of the Pulsed Photothermal Technique for the Measurement of the Convective Heat Transfer Coefficient

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Journal of Thermal Science 2010年第4期19卷 357-363页

作者： M.Rebay A.Arfaoui G.Mebarki R.Ben Maad J.Padet University of Reims GRESPI/Lab de ThermomecaniqueFaculte des SciencesB.P.103951687 ReimsFrance University of Tunis EL MANAR LETTMFaculte des Sciences2092 Manar ⅡTunisia

The present study concerns the measurement of the convective heat transfer coefficient on the solid-fluid interface by the pulsed photothermal *** non-intrusive technique is apphed for the measurement of the local heat transfer coefficients in cooling of a rectangular slab that simulates an electronic *** heat transfer coefficient is deduced from the evolution of the transient temperature induced by a sudden deposit of a luminous energy on the front face of the *** order to draw up the heat transfer cartography by a non-destructive tool, the infrared thermography has been *** inverse techniques for the identification of the heat transfer coefficient are presented *** first one is based on the assumption that heat transfer coefficient remains constant during the pulsed experiment,and the second one considered it variable in space and *** temporal and spatial evolutions are expressed as a constant heat transfer coefficient(h_0)multiplied by a function of time and space f(x,t).The function f is deduced from the resolution of the conjugated convection-conduction problem,by a control volume technique for the case of thermally thick *** results are given for different air velocities and deflection angles of the flow.

关键词： pulsed method infrared thermography convective heat transfer inverse method.

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Electronic and Optical Properties of TiS2 Determined from Generalized Gradient Approximation Study

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Chinese Physics Letters 2015年第9期32卷 96-99页

作者： Hamza El-Kouch Larbi El Farh Jamal Sayah Allal Challioui Laboratoire de mecanique & energetique Departement de Physique Faculte des Sciences Universite Mohmnmed Premier Oujda Maroc Laboratoire de chimie organique macromol~culaire et produits naturels Equipe: Photochimie et Chimie Macromoleculaire Faculte des Sciences Universite Mohammed Premier Oujda. Maroc

The electronic and optical properties of TiS2 are studied of density functional theory. A linearized and augmented by using an ab-initio calculation within the frame plane wave basis set with the generalized gradient approximation as proposed by Perdew et al. is used for the energy exchange-correlation determination. The results show a metallic character of TiS2, and the plots of total and partial densities of states of TiS2 show the metallic character of the bonds and a strong hybridization between the states d of Ti and p of S below the Fermi energy. The optical properties of the material such as real and imaginary parts of dielectric constant （ε（w） = ε1（w）＋ iε2（w））, refractive index n（w）, optical reflectivity R（w）, for E / /x and E / /z are performed for the energy range of 0-.14 eV.

关键词： Ti ab Electronic and Optical Properties of TiS2 Determined from Generalized Gradient Approximation Study

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Pyrolysis of olive residue/low density polyethylene mixture：Part Ⅰ Thermogravimetric kinetics

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燃料化学学报 2008年第6期36卷 672-678页

作者： ABOULKAS A E1 HARFI K El BOUADILI A Laboratoire de Recherche sur la Reactivites des Materiaux et l Optimisation des Procedes ＂REMATOP＂ Departement de chimie Faculte des Sciences Semlalia Universite Cadi Ayyad BP 2390 40001 Marrakech Maroc Departement de chimie Faculte polydisciplinaire de Beni-Mellal Universite Sultan Moulay Slimane BP 592 23000 Beni-Mellal Maroc Laboratoire de Chimie Organique et Analytique Departement de chimie Faculte des Sciences et Techniques de Beni-Mellal Universite Sultan Moulay Slimane BP 523 23000 Beni-Mellal Maroc

This paper demonstrates the thermal pyrolysis of olive residue,low density polyethylene(LDPE) and olive residue/LDPE mixture in an inert atmosphere of N2 using thermogravimetric analysis(TGA).Measurements were carried out in the temperature range 300K^973K at heating rates of 2K/min,10K/min,20K/min and 50K/*** on the results obtained,three temperature regimes were selected for studying the non-isothermal kinetics of olive residue/LDPE *** first two were dominated by the olive residue pyrolysis,while the third was linked to the LDPE pyrolysis,which occurred at much higher *** between the experimental and calculated TG/DTG profiles were considered as a measurement of the extent of interactions occurring on *** maximum degradation temperatures of each component in the mixture were higher than those the individual components;thus an increase in thermal stability was *** kinetic parameters associated with thermal degradation were determined using Friedman isoconversional method.

关键词：高温分解反应低密度聚乙烯动力学 LDPE

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Effect of SnCl2 and SnCl4 precursors on SnSx thin films prepared by ultrasonic spray pyrolysis

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Journal of Semiconductors 2017年第6期38卷 18-23页

作者： Z.Hadef K.Kamli A.Attaf M.S.Aida B.Chouial Laboratoire des Semi-Conducteurs Faculte des Sciences Universite Badji Mokhtar Annaba Algeria Laboratoire de physique des couches minces et applications LPCMA Universite de Biskra Algeria Laboratoire de Couches Minces et Interfaces Faculte des Sciences Universite de Constantine Algeria

Thin films of SnSx,semiconductors,have been successfully synthesized by ultrasonic spray pyrolysis technique,using two precursors namely：tin（II）chloride and tin（IV）chloride,*** solutions were prepared by the dilution of different Sn molarities of the two precursors *** precursor molarities were varied from 0.04 to 0.07 mol/L,whereas that of S was fixed at 0.1 mol/*** present work focuses on the effect of the different precursor’s molarities on the nature and the properties of the prepared thin films in order to optimize the growth conditions.X-ray diffraction analysis reveals that the precursor’s molarities alter the grain size of the prepared films,which varied from 8 to 14 nm and from 12 to 16 nm,according to the used *** films analysis by SEM,shows that the SnS2 films are more dense and smooth than the SnS *** composition of the elements is analysed with an EDX spectrometer,and the obtained result for M（sn）=0：07 mol/L indicates that the atomic ratio of Sn to S is 51.57：48：43 and 36：64 for films synthesized from the first and second precursors *** measurements show that the conductivity behavior depends on the used precursors and their molarities.

关键词： precursors ultrasonic spray tin sulfide semiconductor thin films characterization

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