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Phylogenetic relationship and Molecular Divergence Dating Using SrY Gene Polymorphism about Four Ladoum Sheep Lineages in Senegal

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Open Journal of Animal Sciences 2023年第2期13卷 179-198页

作者： Pape Madiop Sembène Fatimata Mbaye Mama racky Ndiaye Mbacké Sembène Genomic Laboratory Department of Animal Biology Cheikh Anta Diop University Dakar Senegal

Animal genetic resources are playing a vital role in livestock production and are essential to food security. The present study aims to contribute to a better understanding genetic local sheep breeds and to elucidate the phylogenetic relationships through the evolution of the SrY gene in four different lineages of Ladoum sheep raised in Senegal. After a brief analysis of genetic diversity, the phylogenetic relationships and molecular dating were inferred through haplotype networks and four phylogenetic reconstruction methods. The different haplotype networks are constructed with neTWOrK ver. 5.***.0.0 using the Median-Joining method. Phylogenetic trees were reconstructed using neighbor-joining, maximum parsimony, maximum likelihood and Bayesian inference. The robustness of the nodes in phylogenetic trees of the three first methods was assessed by 1000 bootstraps. For Bayesian inference, the posterior probability distribution of the trees was estimated by 4 MCMC chains. 5,000,000 generations were performed for each of the chains by sampling the different parameters every 1000 generations. results show a low polymorphism. Haplotypic diversity is much higher than the average nucleotide divergence between all pairs of haplotypes. The majority and central haplotype indicates a close relationship between “Batling” and “Tyson” individuals. “Birahim” lineage is very distinct from the rest. Phylogenetic trees confirm two genetically separate clades between “Birahim” and the other lineages. The period of divergence between “Birahim” lineage versus the common ancestor of the other three lineages was 2504 years ago. The polyphyly revealed in “Birahim” lindicates that this lineage does not contain the common ancestor of all individuals who compose it. It could therefore be derived from two or more sheep breeds with a common ancestor, Ovis aries. The monophyletic clade appears to be a group including a common ancestor and all of its genetic descendants. This group, bringing togethe

关键词： Genetic Diversity Phylogenetic relationship Molecular Dating SrY Gene Sheeps Ladoum Senegal

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SPUTTErING BEHAVIOUr OF IrON SILICIDES UNDEr LOWEnerGY Ar^+ ION BOMBArDMENT

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Acta Metallurgica Sinica(English Letters) 1999年第6期12卷 0-0,0-0+0-0页

作者： Z.X. Cao E.G. Wang and YX. ne(State Key Laboratory for Surface Physics, Institute of Physics, Beijing 100080, China)

Surface compositions of Fe3Si, FeSi and FeSi2 under 0.1 to 5ke V Ar+ bombaniment have been investigated by using AES method, and the results indicate that the sudece compositions depend strongly on ion enerpy and sample bulk compositions. While in FeSi and FeSi2 only Fe enrichment in the selvage has been observed, in Fe3Si it is Si enriched when the ion enerpy is higher than 31OeV Competition between preferential sputtering and radiation enhanced segmpation is quoted to eoplain this phenomenon.

关键词： preferential sputtering iron silicides radiation enhanced segregation

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Humoral response to Toxoplasma gondii in Pregnant Women in Bangui Central African republic

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Open Journal of Immunology 2022年第4期12卷 122-129页

作者： Wilfrid Sylvain Nambei Junior Ouefio Nguerenam Edwige régina Kodia-Lenguetama Arsène Gbamonza Department of Science Biomedical Faculty of Health Science University of Bangui Bangui Central African Republic National Center of Blood Donor’s Ministry of Public Health Bangui Central African Republic Community Hospital of Bangui Bangui Central African Republic

Toxoplasmosis is a cosmopolitan antrhropozoonosis widespread in mammals and birds. Normally asymptomatic in the subject health, it can have serious consequences for the fetus in the first trimester of pregnancy in the pregnant woman. It is in this context that we propose to assess the immune response to T. gondii in pregnant women in Bangui. This was a retrospective analytical study that consulted the records of pregnant women received in prenatal consultations at the Bangui Community Hospital Maternity ward from January 2019 to December 2019. Socio-demographic and laboratory data (IgM, IgG response to T. gondii) and results of HIV serology were collected from January to June 2021. Chi2 test was used. A total of 307 pregnant women were analyzed. The average age of the women included was 28 (±6) years. The average parity of the entire sample was 2.18 (±1.93). Toxoplasmosis infectious was 14.65%. Women with a positive IgM response accounted for 17.58% and those with an IgG-positive response for 42.99%. Patients with a positive HIV were 5.86%. Patients aged 20 - 29 had a serological profile suggesting a probable ongoing infection (p = 0.010). The paucipares were more represented with no statistically significant difference (p = 0.23). Pregnant women were not significantly exposed to toxoplasmosis infectious (p = 0.96). Immunized and non-immunized subjects were similarly exposed [Or = 0.97;CI 95% 0.4 = 6 - 2.05]. Toxoplasmosis remains particularly serious during pregnancy. Seroprevalence was significantly higher in the 20 - 24 year age group. Women were similarly exposed depending on whether they were immunized or not. This requires the establishment of a specific prevention program against this disease.

关键词： T. gondii Humoral response HIV Pregnant Women Central African republic

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rubella Immunity among Pregnant Women in Bangui, Central African republic

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Open Journal of Immunology 2022年第4期12卷 130-136页

作者： Wilfrid Sylvain Nambei Junior Nguerenam-Ouefio Arsène Gbamonza Edwige régine Kodia-Lenguetama Department of Biomedical Sciences Faculty of Health Sciences University of Bangui Bangui Central African Republic Communautaire Hospital of Bangui Bangui Central African Republic National Center of Blood Donors’ Ministry of Public Health Bangui Central African Republic

Sero-positivity rates of the rubella virus among pregnant women vary from country to country widely throughout the world. In the Central African republic, rubella vaccination is not included in the national immunization schedule. Thus, we propose to evaluate the immune status of pregnant women. This was an analytical retrospective study that consulted the records of pregnant women received in prenatal consultations at the Bangui Community Hospital maternity ward from January to December 2020. Socio-demographic and laboratory data (IgM, IgG) were collected from January to June 2021. Chi2 test was used. A total of 289 pregnant women were analyzed. Women with an IgM+ response accounted for 4.15%. Those with an IgG+ were 14.87%. The distribution by age group shows that patients aged 20 - 24 and those aged 25 - 29 had a rubella profile suggesting persistent infection (p = 0.010). The average age of women included was 28 (±6) years. The average parity for the entire sample was 2.18 (1.93). At any age pregnant women were not significantly exposed to rubella infection (p = 0.96), (Orbrut = 1.03;CI95% = [0.32 - 3.34]). Both immunized and non-immunized individuals are similarly exposed [Or = 0.86;95% IC95% = 0.44 - 1.68] with no difference (p = 0.96). rubella infection remains particularly severe when it occurs during pregnancy. It would be wise to seek immunity in all girls of childbearing age in order to rule out any risk of rubella embryopathy.

关键词： rubella Immunity Pregnant Women Central African republic

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The effect of powder size on the mechanical and corrosion properties and the ignition temperature of WE43 alloy prepared by spark plasma sintering

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Journal of Magnesium and Alloys 2021年第4期9卷 1356-1369页

作者： Drahomír Dvorský JiríKubásek Michaela roudnická Filip Pruša David necas Peter Minárik Jitka Stráská Dalibor Vojtech University of Chemistry and Technology Faculty of Chemical TechnologyDepartment of Metals and Corrosion EngineeringTechnická516628 Praha 6–DejvicePragueCzech Republic Institute of Physics Czech Academy of ScienceNa Slovance 1999/218221 Praha 8PragueCzech Republic Department of Physics of Materials Charles UniversityKe Karlovu 5Prague 12116Czech Republic

Powder metallurgy is a powerful method for the preparation of materials with superior *** work aimed to investigate the effect of powder size on the microstructure,mechanical,and corrosion properties of advanced WE43(Mg-4Y-3rEE-Zr)alloy prepared by spark plasma sintering(SPS).At the same time,the effect of HF pre-treatment of the powder on the properties of final compacted products is *** powder particles yielded microstructure with more interfaces formed by Y_(2)O_(3),or MgF_(2) and YF_(3).These interfaces work as barriers against corrosion,which greatly improves corrosion *** suggested pre-treatment of powder in HF further reduced the corrosion rate of the compacted *** the contrary,fragile interfaces of YF_(3) decreased mechanical properties as the crack primarily propagates through these *** original powder containing the mixture of all powder fractions exerted the best combination of mechanical *** size has also shown to affect ignition *** highest ignition temperature was measured for the finest powder fraction.

关键词： Powder metallurgy Mechanical properties Corrosion Interface SPS

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The Lipid Bilayer of Biological Vesicles: A Liquid-Crystalline Material as Nanovehicles of Information

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Journal of Biomaterials and Nanobiotechnology 2014年第2期5卷 105-115页

作者： Annette Alfsen Ir.ne Tatischeff CNrS & UPMC Honorary research Director Paris France CNrS Honorary research Director Paris France

The biological intracellular vesicles, formed from the cell membr.ne or from different cell organelles, play a main role in the intracellular transport, transfer and exchange of molecules and information. Extracellular vesicles are also detected in organisms belonging to any of the three main branches of evolution, Archaea, Bacteria and Eukarya. There is an increasing consensus that these vesicles are important mediators of intercellular communication. All the intracellular and extracellular vesicles present a characteristic lipid composition and organization that governs their formation, targeting and function. This paper gives an overview of the lipid chemical and physical structure, strongly related to their biological function. The properties and role of the different types of lipids from membr.nes and vesicles are described. Then, their physical structure is shown as self-associated in a bilayer and organized as a lyotropic liquid crystal. The present paper underlies the structural similarity between these biological vesicles and a new synthetic material, the “liquid crystalline fullerodendrimers” obtained from the biological model. It is composed of a basket of carbon associated with a liquid crystalline material and has been shown to exhibit highly efficient properties of information transfer. Our observation stresses the essential role of the liquid crystalline structure of lipids in their function as biological nanovehicles of information. The comparison with the synthetic material contributes to a better understanding of the role of lipids for cell communication in living organisms.

关键词： Coated Vesicles Extracellular Vesicles Lipid Bilayer Liquid Crystalline Material

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A new Biological Strategy for Drug Delivery: Eucaryotic Cell-Derived Nanovesicles

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Journal of Biomaterials and Nanobiotechnology 2011年第5期2卷 494-499页

作者： Ir.ne Tatischeff Annette Alfsen 不详

An efficient drug delivery is the prerequisite of the successful chemotherapeutic treatments of many human diseases. Despite a great number of approaches, the improvement of drug cell internalization remains an actual research challenge. We propose a new biological delivery system based on the extracellular vesicles released by a non-pathological eukaryotic microorganism, Dictyostelium discoideum. After a summary of the main characteristics of these extracellular vesicles, including of their lipid bilayer that appears as a good candidate for initiating membr.ne fusion, followed by delivery of their encapsulated drug, the capacity of these vesicles to convey drugs into human cells was demonstrated in vitro on two tumor cell lines, resistant leukaemia K562r and cervix carcinoma HeLa cells. A comparison with other extracellular vesicles, like exosomes or bacteria-derived particles, stresses the unique properties of Dictyostelium extracellular nanovesicles for drug delivery.

关键词： Biological Extracellular Vesicles Antitumoral Drug Delivery Dictyostelium discoideum

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Osteocyte pericellular and perilacunar matrices as markers of bone-implant mechanical integrity

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BIOCELL 2022年第10期46卷 2209-2216页

作者： reMY GAUTHIEr HeLÈne FOLLET ANA-MArIA TrUNFIO-SFArGHIU DELPHIne FArLAY NINA ATTIK SYLVAIN MEILLE JerÔME CHEVALIEr DAVID MITTON Universite de Lyon CNRSINSA de LyonUniversite Claude Bernard Lyon 1MATEISUMR5510VilleurbanneF-69621France Universite de Lyon Universite Claude Bernard Lyon 1INSERMLYOS UMR 1033LyonF-69008France Universite de Lyon INSA-LyonCNRS UMR5259LaMCoSVilleurbanneF-69621France Universite de Lyon Universite Claude Bernard Lyon 1UMR CNRS 5615Laboratoire des Multimateriaux et InterfacesVilleurbanneF-69622France Universite de Lyon Universite Claude Bernard Lyon 1Faculte d’OdontologieLyonF-69008France Universite de Lyon Universite Gustave EiffelUniv Claude Bernard Lyon 1LBMC UMR_T 9406LyonF-69622France

To develop durable bone healing strategies through improved control of bone repair,it is of critical importance to understand the mechanisms of bone mechanical integrity when in contact with biomaterials and *** mechanical integrity is defined here as the adaptation of structural properties of remodeled bone in regard to an applied mechanical ***,the authors present why future investigations in bone repair and regeneration should emphasize on the matrix surrounding the *** are mechanosensitive cells considered as the orchestrators of bone remodeling,which is the biological process involved in bone *** bone cells are trapped in an interconnected porous network,the lacunocanalicular.network,which is embedded in a bone mineralized extracellular *** a consequence of an applied mechanical loading,the bone deformation results in the deformation of this lacunocanalicular.network inducing a shift in interstitial fluid pressure and velocity,thus resulting in osteocyte *** material environment surrounding each osteocyte,the so called perilacunar and pericellular matrices properties,define its *** this mechanical stimulation pathway is well known,the laws used to predict bone remodeling are based on strains developing at a tissue scale,suggesting that these strains are related to the shift in fluid pressure and velocity at the lacunocanalicular *** this relationship has been validated through observation in healthy bone,the fluid behavior at the bone-implant interface is more *** presence of the implant modifies fluid behavior,so that for the same strain at a tissue scale,the shift in fluid pressure and velocity will be different than in a healthy bone *** that context,new markers for bone mechanical integrity,considering fluid behavior,have to be *** viewpoint exposed by the authors indicates that the properties of the pericellular and the perilacunar

关键词： Bone mechanical integrity Osteocytes Pericellular Perilacunar Mechanosensitivity

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Full Cycle Cold Flow Analysis of the Effect of Twin Swirl Combustion Chamber Design in a Diesel Engine

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World Journal of Mechanics 2016年第4期6卷 109-117页

作者： Doğan Güneş Mehmet Serkan Horasan Mechanical Engineering Department Istanbul Bilgi University Istanbul Turkey

new designs and adaptation methods are experimented to ensure compliance to ever increasing emissions and efficiency requirements of modern diesel engines. Piston head structure which influences the mixing rate and timing of the fuel within in the combustion chamber is known to enable increase in combustion efficiency and thus lower emission rates. In this paper, computation analysis of flow within a diesel engine cylinder with a twin swirl combustion chamber design throughout a full cycle is presented. The results obtained indicate that the effect of the twin swirl combustion chamber on the cold flow conditions is noteworthy and further analysis together with experiments may reveal information that may prove to be useful in further.new designs.

关键词： Cold Flow Analysis Combustion Chamber Design Internal Combustion Engine Diesel Engine

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Diversity and Genetic Structuration of Populations of <i>Plutella xylostella</i>(Lepidoptera, Plutellidae), Cabbage Farming Destroyer in Senegal

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Advances in Entomology 2022年第1期10卷 1-13页

作者： Toffène Diome Mamecor Faye Marième Seck Cheikh Tidiane Niass Mbacké Sembène Genetic Team and Population Management Department of Animal Biology Faculty of Sciences and Technology Cheikh Anta Diop University Dakar Senegal Laboratory of Parasitology Department of Animal Biology Faculty of Sciences and Technology Cheikh Anta Diop University Dakar Senegal

Plutella xylostella, pointed out as the most dangerous destroyer of cabbage (Brassica olerarea), is a cosmopolitan species. In fact, owing to its large capacity of adaptation, P. xylestella colonizes any kind of area. This insect can bring about up to 90% of losses on cabbage farming. To control the insect, Senegalese farmers, very often, resort to high dose of chemical pesticides which are repetitively sprayed. The use of these chemical products gives rise to different varieties of resistant insects, which results in the emergence of different haplotypes between populations. It is in such a context that this study has been undertaken. Our objective is then to contribute to the knowledge of the genetic diversity of P. xylostella populations in Senegal. To hit the target, PCr- Sequencing method has been applied on samples from the five following localities: Diofior, Malika, Mboro, Santh Ndong, and Sebikotane. P. xylostella from Mboro is genetically different from the other populations. This fact could be due to a different way of using pesticides in this area vis-à-vis of the other localities. On the other hand, between populations of P. xylostella from Diofior, Malika, Santh Ndong, and Sebikotane, there is no significant genetic difference. In other respects, phylogenetic trees reveal the existence of two clades: one with individuals from Mboro and the other one with individuals from the other four localities. P. xylostella from Mboro distinguishes itself from other populations and then, can be regarded as a sub-population. Thus, the phylogenetic trees reveal the existence of two groups of P. xylostella in Senegal.

关键词： Brassica oleracea Genetic Diversity Genetic Structure

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