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On a diffusive bacteriophage dynamical model for bacterial infections

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生物数学学报:英文版 2023年第7期16卷 47-89页

作者： Hyacinthe m.Ndongmo Teytsa Berge Tsanou jean Lubuma Samuel Bowong Department of mathematics and Computer Science University of Dschang P.O.Bor 67DschangCameroon Department of mathematics and Applied mathematics University of Pretoria Pretoria 0002South Africa IRD UmI 209 UmmISCO University of Yaounde I P..Bor 337YaoundeCameroon LIRImA-EPITAG Team Project University of Yaounde I P.O.Bor 812YaoundeCameroon Department of mathematics and Computer Science University of Douala P.0.Bor 24157DoualaCameroon

Bacteriophages or phages are viruses that infect bacteria and are increasingly used to control bacterial *** develop a reaction-diffusion model coupling the interactive dynamic of phages and bacteria with an epidemiological bacteria-borne disease *** the submodel without phage absorption,the basic reproduction number Ro is *** disease-free equilibrium(DFE)is shown to be globally asymptotically stable whenever Ro is less than one,while a unique globally asymptotically endemic equilibrium is proven whenever Ro exceeds *** the presence of phage absorption,the above stated classical condition based on Ro,as the average number of secondary human infections produced by susceptible/lysogen bacteria during their entire lifespan,is no longer suficient to guarantee the global stability of the *** thus derive an additional threshold No,which is the average offspring number of lysogen bacteria produced by one infected human during the phage-bacteria interactions,and prove that the DFE is globally asymptotically stable whenever both Ro and No are under unity,and infections persist uniformly whenever Ro is greater than ***,the discrete counterpart of the continuous partial differential equation model is derived by constructing a nonstandard finite difference scheme which is dynamically *** consistency is shown by constructing suitable discrete Lyapunov functionals thanks to which the global stability results for the continuous model are *** scheme is implemented in matLab platform and used to assess the impact of spatial distribution of phages,on the dynamic of bacterial infections.

关键词： Bacterial infections diffusion NSFD phage absorption global stability

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

Epidemiological, Clinical and Evolutionary Aspects of Human African Trypanosomiasis in Children in Nola

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Open Journal of Pediatrics 2024年第2期14卷 344-358页

作者： Brice Olivier Bogning mejiozem Gaspard Tékpa Synthia Ningatoloum Nazita Jocelyn Tony Nengom Danebera Lydie Verlaine Carine Judith Kiteze Nguinzanémou Rostand Juste Koyangboi Kombaya Iris Vanessa Gaspiet Sonny jean Chrysostome Gody Complexe Hospitalier Pédiatrique de Bangui Bangui République Centrafricaine Service des maladies Infectieuses H&#244pital de l’Amitié Bangui République Centrafricaine Faculté des Sciences de la Santé de l’Université de Bangui Bangui République Centrafricaine Centre Hospitalo Universitaire Communautaire de Bangui Bangui République Centrafricaine Faculté de médecineet des Sciences Biomédicales Université de Yaoundé 1 Yaoundé Cameroun

Background: Human African trypanosomiasis (HAT) occurs in three historical foci in the Central African Republic. Objective: To describe the morbi-mortality of childhood HAT in rural Central African Republic with the aim of early management. methods: Descriptive and analytic cross-sectional study conducted from January 1, 2017 to march 30, 2018 at Nola prefectural hospital. This study was included all children seen as outpatients and/or hospitalized in the pediatric wards, in whom the diagnosis of HAT was confirmed. Statistical analysis was performed using Epi-info software. Results: Forty children were included from Bilolo (60%), Nola (30%) and Salo (10%). The sex ratio was 0.66 with a median age of 8.65 ± 12.48 years. Fever (82.5%), nocturnal insomnia (75%), daytime somnolence (67.5%), headache (65%), polyarthralgia (62.5%), convulsions 52.5% (n = 21), tremor (27.5%), trypanidism (7.5%) and delirium (2.5%) were the main functional signs. Examination signs were adenopathy (52.5%), paresthesia (30%), decreased cutaneous-abdominal reflexes (25%) and osteoarticular reflexes (17.5%), hyperesthesia (20%), extrapyramidal hypertonia (15%) and depression (2.5%). The children were in the lymphatic-blood phase in 65% of cases, and meningoencephalitis in 35%. Pentamidine was administered in 65% of cases. Four children died and 6 had neurological sequelae. There was an association between age under 5, Bilolo’s focus, the children’s history and the severity of the disease. Age under 5, gender, household, children’s activity, history and occurrence of sequelae were also associated. Conclusion: HAT remains a permanent threat to Central African children. Any clinical presentation combining long-term infectious signs and unexplained neurological or neuropsychological disorders must be treated with caution.

关键词： morbidity-mortality Child HAT Nola CAR

Low-k integration: Gas screening for cryogenic etching and plasma damage mitigation

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Frontiers of Chemical Science and Engineering 2019年第3期13卷 511-516页

作者： Romain Chanson Remi Dussart Thomas Tillocher P. Lefaucheux Christian Dussarrat jean Francois de m arneffe ImEC v.z.w. 3001 LeuvenBelgium GREmI/University of Orleans OrleansFrance Air Liquide Laboratories TsukubaJapan

The integration of porous organo-silicate low-k materials has met a lot of technical *** of the main issues is plasma-induced damage,occurring for all plasma steps involved during interconnects *** the present paper,we focus on porous SiOCH low-k damage mitigation using cryogenic temperature so as to enable micro-capillary *** aim is to protect the porous low-k from plasma-induced damage and keep the k-value of the material unchanged,in order to limit the RC delay of interconnexion levels while shrinking the microchip *** cryogenic temperature is used to condense a gas inside the porous low-k ***,the etching process is performed at the temperature of condensation in order to keep the condensate trapped inside the material during the *** the first part of this work,the condensation properties of several gases are screened,leading to a down selection of five ***,their stability into the porous structure is evaluated at different *** of them are used for plasma damage mitigation *** mitigation is effective and shows negligible damage for one of the gases at-50℃.

关键词： low-A nanotechnology micro-electronics cryo-etching plasma processing

COVID-19/Tuberculosis Co-Infection at the Epidemic Treatment Center (ETC) of Saint-Louis (Senegal): About 9 Cases

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Prevalence and Factors Associated with Virologic Failure among People Living with HIV (PLHIV) monitored in a Decentralized Health Care Facility

Advances in Infectious Diseases（传染病进展） 2024年第1期 56页

作者： Alassane Dièye moustapha Diedhiou Papa Latyr Junior Diouf mba Bambo Diakhaby Demba makalou Samba Niang Diatou Dia-Gueye Amadou Diop Dia Ibrahima Louis martin Dieng Seynabou Lô Ndéye m.ry Dia-Badiane

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Advances in Infectious Diseases 2019年第3期9卷 226-237页

作者： Selly Ba Ndeye Diama Ba Lamanatou Sembene Habibatou Dia mohamed Coulibaly jean Louis Ndiaye Ndeye m.ry Dia Cheikh Tidiane Ndour Doctoral School of Thies University Thies Senegal Intrahealth International Dakar Senegal Roi Baudouin Hospital Dakar Senegal AIDS monitoring Unit/ministry of Health Dakar Senegal Department of Health Gaston Berger University Saint Louis Senegal

Introduction: In Senegal, the decentralization of Health Care Centers has contributed significantly to the intensification of antiretroviral treatment. However, Care providers are still facing the treatment optimizing challenge. Objectives: To determine the prevalence of virologic failures of PLHIV monitored in a decentralized Health care center and to determine associated factors. Patients and methods: This is a cross-sectional descriptive and analytical study of PLHIV, aged 18 years and over, on first-line treatment, monitored onsite from February 1st to December 31st, 2018. A data collection form was completed from medical records (clinical, immuno-virologic and evolutionary). Any VL > 1000 cp/ml after 6 months of antiretroviral therapy (ART) was considered as virologic failure. Data were captured and analysed using the EPI INFO 2002software. Chi-square test and the Fisher test were used to compare the proportions;a value of p ≤ 0.05 was considered significant. Results: 331 patients were treated with HIV-1 profile in 89% of cases. A proportion of 55% was married and 97% came from rural areas. 80% were either not or poorly educated. The median of age was 44 ± 11 years with a F/m ratio of 3.4. At baseline, 56% were symptomatic at stage 3 or 4 of WHO. They had severe immunosuppression with a median CD4 count of 217 ± 187 cells/mm3, the viral load was detectable in half of the patients with a median VL of 97,000 cp/ml ± 70,569. The antiretroviral regimen combined 2 NRTIs with 1 NNRTI in 88% of cases. The median of follow-up was estimated at 60 ± 43 months. The prevalence of virologic failure was 19%. This prevalence was associated with age less than 25 years (p = 0.04), late diagnosis (CD4 at baseline less than 200 cel/mm3 (p = 0.002), stage 3 or 4 WHO (p = 0.04) High viral load greater than 10,000 (p = 0.04) at baseline. Conclusion: These results suggest making the new therapeutic classes accessible for first-line treatment.

关键词： ART Virologic Failure Associated Factors

Density Results in Sobolev Spaces Whose Elements Vanish on a Part of the Boundary

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Chinese Annals of mathematics,Series B 2011年第6期32卷 823-846页

作者： jean-marie Emmanuel BERNARD Laboratoire Analyse et Probabitilités Université d'Evry val d'Essonne23 Boulevard de France91037 EVRYFrance

This paper is devoted to the study of the subspace of Wm＇＂ of functions that vanish on a part γ0 of the boundary. The author gives a crucial estimate of the Poincare constant in balls centered on the boundary of γ0. Then, the convolution-translation method, a variant of the standard mollifier technique, can be used to prove the density of smooth functions that vanish in a neighborhood of γ0, in this subspace. The result is first proved for m = 1, then generalized to the case where m 〉 1, in any dimension, in the framework of Lipschitz-continuous domain. However, as may be expected, it is needed to make additional assumptions on the boundary of γ0, namely that it is locally the graph of some Lipschitz-continuous function.

关键词： Density results Boundary value problems Sobolev spaces

Simple Fabrication and Characterization of Discontinuous Carbon Fiber Reinforced Aluminum matrix Composite for Lightweight Heat Sink Applications

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Acta metallurgica Sinica(English Letters) 2014年第4期27卷 714-722页

作者： Hiroki Kurita Emilien Feuillet Thomas Guillemet jean-marc Heintz Akira Kawasaki jean-Francois Silvain DEN/DANS/DmN/SRmA/LTmEx CEA SaclayGif-sur-YvetteFrance Institute of Condensed matter Chemistry of Bordeaux BordeauxFrance Department of materials Processing Graduate School of EngineeringTohoku University

The constant increase in power and heat flux densities encountered in electronic devices fuels a rising demand for lightweight heat sink materials with suitable thermal *** this study,discontinuous pitch-based carbon fiber reinforced aluminum matrix（Al-CF） composites with aluminum–silicon alloy（Al–Si） were fabricated through hot *** small amount of Al–Si contributed to enhance the sintering process in order to achieve fully dense Al–CF composites.A thermal conductivity and CTE of 258 W/（m K） and 7.0 9 10-6/K in the in-plane direction of the carbon fibers were obtained for a（Al95 vol%＋ Al–Si5 vol%）-CF50 vol%*** fiber provides the reducing of CTE while the conservation of thermal conductivity and weight of *** achieved CTEs satisfy the standard requirements for a heat sink material,which furthermore possess a specific thermal conductivity of 109 W cm3/（m K g）.This simple process allows the low-cost fabrication of Al–CF composite,which is applicable for a lightweight heat sink material.

关键词： Carbon fiber metal-matrix composites(mmCs) Thermal properties Powder processing

Basic belief assignment approximations using degree of non-redundancy for focal element

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Chinese Journal of Aeronautics 2019年第11期32卷 2503-2515页

作者： Yi YANG Deqiang HAN jean DEZERT SKLSVmS School of AerospaceXi'an Jiaotong UniversityXi'an 710049China Center for Information Engineering Science Research XVan Jiaotong UniversityXi'an 710049China ONERA The French Aerospace LabChemin de la HunierePalaiseau F-91761France

Dempster-Shafer evidence theory, also called the theory of belief function, is widely used for uncertainty modeling and reasoning. However, when the size and number of focal elements are large, the evidence combination will bring a high computational complexity. To address this issue,various methods have been proposed including the implementation of more efficient combination rules and the simplifications or approximations of Basic Belief Assignments(BBAs). In this paper,a novel principle for approximating a BBA into a simpler one is proposed, which is based on the degree of non-redundancy for focal elements. more non-redundant focal elements are kept in the approximation while more redundant focal elements in the original BBA are removed first. Three types of degree of non-redundancy are defined based on three different definitions of focal element distance, respectively. Two different implementations of this principle for BBA approximations are proposed including a batch and an iterative type. Examples, experiments, comparisons and related analyses are provided to validate proposed approximation approaches.

关键词： BBA approximation Belief functions Evidence theory Focal element Non-redundancy