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Journal of Environmental Sciences 2017年第3期29卷 48-59页

作者： Jonathan Colombet Agnès Robin télesphore sime-ngando Laboratory Microorganisms:Oenome and Environment Clermont University Blaise PascalUMR CNRS 602324 avenue des LandaisBP 80026F-63171 AubiereFrance CIRAD UMR Eco&Sols2 place Viala34060 Montpellier Cedex 1France

We examined changes in morphological and genomic diversities of viruses by means of transmission electronic microscopy and pulsed field gel electrophoresis （PFGE） over a nine-month period （April-December 2005） at four different depths in the oligomesotrophic Lac Pavin. We found that the majority of viruses in this lake belonged to the family of Siphouiridae or were untailed, with capsid sizes ranging from 30 to 60 nm, and exhibited genome sizes ranging from 15 to 45 kb. On average, 12 different genotypes dominated each of the PFGE fingerprints. the highest genomic viral richness was recorded in summer （mean = 14 bands per PFGE fingerprint） and in the epilimnion （mean = 13 bands per PFGE fingerprint）. Among the physico-chemical and biological variables considered, the availability of the hosts appeared to be the main factor regulating the variations in the viral diversity.

关键词： VirusLac PavinDynamicMorphological diversity Genomic diversity

Impact of Rice Stem Borers and Identification of <i>Orseolia oryzivora</i>Harris &Gagné, 1982 (Diptera: Cecidomyiidae) Biotypes in the Southern Cameroon

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Agricultural Sciences 2020年第2期11卷 111-123页

作者： Karine Moche Paul-Alain Nana Liliane tandzi Ngoune Champlain Djieto-Lordon Noé Woin télesphore sime-ngando Laboratory of Entomology Institute of Agricultural Research for Development Yaoundé Cameroon Department of Oceanography and Limnology Institute of Fisheries and Aquatic Sciences University of Douala Douala Cameroon Laboratory Microorganisms: Genome and Environment (LMGE) Clermont Auvergne University Clermont-Ferrand France Department of Agriculture College of Basic and Apply Sciences University of Ghana Legon Ghana Laboratory of Zoology Faculty of Science University of Yaoundé Yaoundé Cameroon

the study compares the impact due to rice stem borers in two sites (Yaoundé and Ntui). It also shows the diversity of the African Rice Gall Midge (AfRGM) biotypes in southern Cameroon (Santchou, Ndop, tonga, Ebolowa, Ba?gom, Yaoundé and Ntui). the New Rice for Africa (NERICA) varieties 3, 8, 9 and 13 sown in Ntui were less attacked than those sown in Yaoundé. At both sites, damages ranged from 0.78% to 2.7%. In terms of diversity, the main stem-borer species were O. oryzivora, Diopsis apicalis, D. longiconis and Chilo zacconius. Molecular analyses of Orseolia oryzivora larvae collected in the localities of Santchou, Ndop, tonga, Ebolowa, Ba?gom and Yaoundé showed the existence of more than one O. oryzivora biotype in southern Cameroon’s rice basins.

关键词： Biotype Larvae NERICA Orseolia sp PCR

Diversity and Structure of the Prokaryotic Communities Indigenous to two Volcanic Lakes: Nyos and Monoun in Cameroon

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Open Journal of Ecology 2020年第9期10卷 632-650页

作者： Paul-Alain Nana Moïse Nola Geneviève Bricheux Zéphyrin Fokam Pierre Ngassam Dickson Achuo Enah Jonathan Colombet Agnès Vellet Anne Mone Viviane Ravet Didier Debroas télesphore sime-ngando Department of Oceanography Institute of Fisheries and Aquatic Sciences University of Douala Douala Cameroon Laboratory of Hydrobiology and Environment Faculty of Science University of Yaoundé I Yaoundé Cameroon Laboratory Microorganisms: Genome and Environment UMR CNRS 6023 Clermont Auvergne University Clermont-Ferrand France Department of Biology Higher Teacher Training College University of Bamenda Bamenda Cameroon

this study explores the diversity and structure of prokaryotic communities (Archaea and Bacteria) of 2 tropical volcanic lakes (Nyos and Monoun) in Cameroon, using 16SrRNA sequences. Metagenomics analysis of sequences showed that most OtUs (Operational taxonomic Units) were associated with 26 phyla (23 for Bacteria and 3 for Archaea) in Nyos and 36 phyla (33 for Bacteria and 3 for Archaea) in Monoun. In both lakes, Proteobacteria for Bacteria and Crenarchaea for Archaea were predominant and present at all depths but in different proportions. Bacterial community compositions were generally dominated by members of Proteobacteria, Firmicutes, Actinobacteria, Chloroflexi and Bacteroidetes covering about 98% of the sequences. Crenarchaea, thaumarchaea and Euryarchaea were the three main phyla of Archaea common to both lakes. the amount of virus and total bacteria was determined by flow cytometry technic and the evaluated ratio ranged from 0.2 to 1.2 at Nyos and from 0.6 to 2.6 at Monoun. For both lakes, the correlation was very significant between viruses and total bacteria. the depth-dependent variability is discussed with chemical and physical environmental parameters. these could significantly influence virus-mediated bacterial lysis and abundance and vertical stratification of the prokaryotic community.

关键词： Bacteria Flow Cytometry Lakes Nyos and Monoun OtUs Viruses

Design Optimization of a Lattice tower: Structure and Foundations

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Open Journal of Applied Sciences 2024年第2期14卷 483-493页

作者： Cossi télesphore Nounangnonhou Guy Clarence Semassou Kossoun Alain tossa Noémie Sintondji Laboratory of Energetics and Applied Mechanics (LEMA) University of Abomey-Calavi Abomey-Calavi Benin Laboratory of Electrotechnics Telecommunications and Applied Informatics (LETIA) University of Abomey-Calavi Abomey-Calavi Bénin

Produced in power plants, electrical energy is transported to places of consumption via the electricity network. At the heart of this network are the supports that allow electricity to be efficiently transported over long distances, guaranteeing the security and supply of energy to the various centers of use. In the construction of a line, supports occupy an important part in terms of safety and construction cost. It is therefore essential to optimize their use to reduce the cost of transmission lines. this work addresses this problem, which focuses on the optimal utilization of X-lattice towers in the construction of overhead power lines. the challenge is to reconcile the search for optimal cost and respect for the design, resistance and service constraints of the structure. to do this, a parameter having a strong correlation with the weight, foundation and construction cost of the X-lattice tower for 161 kV lines is determined as an important cost variable. this parameter is the wheelbase of the towers. the junction point between the structure and the foundations is obtained by measuring the forces at the base of the tower following the lowering of the loads. these efforts make it possible to size foundations which are of the inverted or isolated sole type. the results obtained reveal that from 8 meters in width, the wheelbase gradually changes until the optimum is obtained at 6.29 meters. With this wheelbase, the production cost is optimal. It clearly emerges from this study that the construction of lattice pylons with a wheelbase of approximately 6.29 meters makes it possible to optimize the cost of construction of 161 kV lines in the Republic of Benin.

关键词： Lattice tower Wheelbase Cost Optimization Foundation

the Role and Place of Artificial Neural Network Architectures Structural Redundancy in the Input Data Prototypes and Generalization Development

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Journal of Computer and Communications 2024年第7期12卷 1-11页

作者： Conrad Onésime Oboulhas tsahat Ngoulou-A-Ndzeli Béranger Destin Ossibi Ecole Nationale Suprieure Polytechnique Universit Marien Ngouabi Brazzaville Republic of Congo

Neural Networks (NN) are the functional unit of Deep Learning and are known to mimic the behavior of the human brain to solve complex data-driven problems. Whenever we train our own neural networks, we need to take care of something called the generalization of the neural network. the performance of Artificial Neural Networks (ANN) mostly depends upon its generalization capability. In this paper, we propose an innovative approach to enhance the generalization capability of artificial neural networks (ANN) using structural redundancy. A novel perspective on handling input data prototypes and their impact on the development of generalization, which could improve to ANN architectures accuracy and reliability is described.

关键词： Multilayer Neural Network Multidimensional Nonlinear Interpolation Generalization by Similarity Artificial Intelligence Prototype Development

the Place of Nursing theory in the Management of Post-Operative Infections in a Hospital Environment: Case of Cibitoke District Hospital

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Open Journal of Nursing 2024年第5期14卷 225-238页

作者： Onésime Nduwimana Le Béni Bugingo Arlette Ntigura Ishimwe Abias Nibaruta Faculty of Health Sciences Hope Africa University Bujumbura Burundi Faculty of Health Sciences Integrated Polytechnic University Cibitoke Burundi

Introduction: Post-operative infections, such as surgical site infections (SSIs), are a significant concern in healthcare settings. Nurses play a crucial role in the prevention and management of these infections. the use of nursing theory could contribute to the prevention of SSIs. the aim of this study was to evaluate the role of nursing theory in the management of surgical site infections (SSIs) in a hospital environment. Method: A cross-sectional study was conducted using descriptive and analytical methods to assess the role of nursing theory in the management of Post-operative infections (POI) in a hospital setting in October 2023. the study population consisted of nurses working in the Surgery, Emergency, and Maternity units at Cibitoke District Hospital. A sample size of 71 nurses working full or part time in the Surgery were invited to participate in this study. A questionnaire was used to collect the data, and SPSS version 21.0 software was used for analysis. Results: the study found that nursing theory did not have any statistically significant place in the management of POI (p-value = 0.523). However, the results showed that experience was the only significant factor influencing the management of POI (p-value = 0.004). this is explained by the analysis of the net effects of the explanatory variable where we noticed that those who had more experience were more likely to manage post-operative infections. the participants’ knowledge regarding nursing theory in the management was poor as they scored less than 30% in all the variables used to measure their knowledge. Conclusion: the study revealed that nurses’ knowledge of nursing theories and their applications in the management of SSIs was poor. Continuing professional development, curriculum review, and in-service training were highly recommended.

关键词： Nurses Postoperative Infection Surgical Site Infections Management Nursing theory

Assessment of the Recent Hydromorphological Features of Nokoue Lake and Its Channels (South-East Benin)

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Open Journal of Modern Hydrology 2024年第1期14卷 33-55页

作者： tètchodiwèï Julie-Billard Yonouwinhi Gérard Alfred Franck Assiom d’Almeida Felix Kofi Abagale Akuemaho Virgile Onésime Akowanou Laboratory of Applied Hydrology (LHA) National Institute of water (INE) African Centre of Excellence for Water and Sanitation (C2EA) University of Abomey-Calavi (UAC) Cotonou Benin International Chair in Mathematical Physics and Applications (ICMPA–UNESCO Chair) University of Abomey-Calavi (UAC) Cotonou Benin Laboratory of Geology Mining and Environment (LGME) Faculty of Science and Technology (FAST) University of Abomey-Calavi (UAC) Cotonou Benin West African Centre for Water Irrigation and Sustainable Agriculture (WACWISA) University of Development Studies (UDS) Tamale Ghana Laboratory of Sciences and technology for Water and Environment (LStEE) University of Abomey-Calavi (UAC) Cotonou Benin

Based on 2022 and 2023 hydrometric data and satellite images (Sentinel 2022, SPOt 2010), this study aims to present the Nokoué Lake and its channels’ re-cent hydromorphological characteristics. Integrating flow, tributary morphology, and topography data determined specific power values along the axes studied. the values obtained range from 2.69 to 12.92 W/m2 for Ouémé River and 2.46 to 10.99 W/m2 for Sô River. the resulting water erosion on banks and bottoms is of linear, areolar, or gully and claw types. Lake bathymetry varies from -0.5 to -2.6 m (low flow period) and -1 to -4 m;in the Ouémé, Sô, and totchè rivers, it varies from -5 m to -7 m, reaching -10 m at the Cotonou channel entrance (flood period). Bathymetric profiles reveal varied “U”, “V” and “Intermediate” bottom morphologies, influenced by erosion/sedimentation processes and human activities. the flow facies identified are lentic in the northern tributaries and lotic in the Cotonou and totchè canals. Spatial analysis identified nine (09) thematic classes. In 2022, the surface area of the water body has increased from 274 km2 at low water to 280 km2 at high water, whereas in 2010 (a recent year of exceptional flooding), the surface area was 270 km2 at low water and 277 km2 at high water. Significant changes in land use are observed between 2010 and 2022. the floodplain area decreased slightly, from 421 km2 in 2010 (year of exceptional flooding) to 419 km2 in 2022. the evolution of land use shows a progressive expansion of the urban environment to the detriment of the natural environment. In the medium to long term, this trend could threaten the hydromorphological balance and even the existence of this important lagoon ecosystem.

关键词： Nokoué Lake Ouémé River Sô River Cotonou Channel Hydromorphology

Application of the N + 2 transversal Network Method to the Study of a Coupled Resonator Filter

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Open Journal of Applied Sciences 2024年第6期14卷 1412-1424页

作者： Charmolavy Goslavy Lionel Nkouka Moukengue Conrad Onésime Oboulhas tsahat Haroun Abba Labane Barol Mafouna Kiminou Achille Makouka Electrical and Electronic Engineering Laboratory ENSP Marien Ngouabi University Brazzaville Congo Electrical Engineering Research Laboratory Polytechnic University of Mongo Mongo Tchad

this paper presents a new approach to synthesize admittance function polynomials and coupling matrices for coupled resonator filters. the N + 2 transversal network method is applied to study a coupled resonator filter. this method allowed us to determine the polynomials of the reflection and transmission coefficients. A study is made for a 4 poles filter with 2 transmission zeros between the N + 2 transversal network method and the one found in the literature. A MAtLAB code was designed for the numerical simulation of these coefficients for the 6, 8, and 10 pole filter with 4 transmission zeros.

关键词： Resonator Filter Coupling Matrix transmission Zero transversal Network Method

Preparation of microparticles and nanoparticles using membrane-assisted dispersion,micromixing,and evaporation processes

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Particuology 2024年第1期84卷 30-44页

作者： Goran t.Vladisavljevic Chemical Engineering Department Loughborough UniversityLoughboroughLeicestershire LE113TUUnited Kingdom

Synthetic microporous membranes are increasingly used for energy-efficient and controlled production of micro-and nanoparticles and micro-and nanoemulsions with tuneable morphology and physico-chemical properties through various micromixing,emulsification,and evaporation *** emul-sification processes,the membrane pores are used for dispersed phase injection and size-controlled generation of droplets and droplet-templated *** micromixing processes,membrane is utilised as a micromixer for mixing two miscible liquids,usually solvent and antisolvent-rich solutions,which leads to the creation of supersaturation and subsequent nanoprecipitation or *** mem-brane evaporation processes,membrane is used to prevent phase dispersion while allowing efficient molecular diffusion of solvent and/or antisolvent vapour through gas-filled *** dispersion processes can be operated continuously by decoupling shear stress on the membrane surface from cross flow using tube insets,flow pulsations,swirling flow,membrane oscillations or membrane *** generation and solidification can be performed continuously in a single pass by connecting membrane module with a downstream *** dispersion processes can be used for pro-duction of nanoparticles such as nanovesicles(liposomes,micelles,ethosomes,and niosomes),nanogels,polymeric,lipid and metallic nanoparticles,and *** main advantages of membrane-assisted particle generation are in low energy consumption,controlled geometry and hydrodynamic conditions at the microscale level,flexible throughput due to modular and scalable design of membrane devices,and a wide choice of available microporous membranes with various wall porosities,wetta-bilities,pore sizes,and pore morphologies to suit different applications.

关键词： Nanoparticles Microparticles Nanoemulsions Microemulsions Microporous membrane Crystallisation Flash nanoprecipitation Emulsification Zero liquid discharge

Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.t.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

the Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. these symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas