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General Exponential Distribution: Bayes Estimation under Entropy Loss Function

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General Exponential Distribution: Bayes Estimation under Ent...

作者： cyrille-clovis moypemna-sembona（希林）吉林大学

学位级别：硕士

1825年,Benjamin Gompertz引入了Gompertz-Makeham法则.他运用如下的分布函数来描述死亡率的增长,下面我们来考虑一种特殊情况. 事实上,Gupta&Kundu(1999)考虑了这个模型在ρ=1时的特殊情形,通过使用双参数指数分布.广义指数(Generalize... 详细信息

1825年,Benjamin Gompertz引入了Gompertz-Makeham法则.他运用如下的分布函数来描述死亡率的增长,下面我们来考虑一种特殊情况. 事实上,Gupta&Kundu(1999)考虑了这个模型在ρ=1时的特殊情形,通过使用双参数指数分布.广义指数(Generalized Exponential)分布函数为:密度函数为其中α,λ分别是形状参数和尺度参数. 在这篇文章中,我们给出了多种广义指数分布的参数估计方法,例如,熵损失函数下贝叶斯估计,极大似然估计以及最优不变估计过程,并且通过表格3.1与3.2比较了它们的模拟结果. 事实上,λ和α是非负独立的,并且先验分布为服从如下伽玛分布的先验变量: 在本文第二章中,我们主要讨论了上述提到的三种估计方法,分别为: §2.1部分我们主要考虑了极大似然估计(MLE)方法;§2.2部分我们主要讨论了熵损失下的最优不变估计过程;§2.3给出了熵损失下的Bayes估计方法.通过这些不同的估计方法,我们可以得到一些重要的结果为:其中,是φ(λ)=λ的解(见(2.1.1)).它的线形逼近公式为, (见(2.37) ) ,并且通过蒙特卡罗方法可以得到(见(2.40)). 由于通过这些估计方法得到的参数估计很难用显式解来表示,因此,第三章主要讨论了怎样用计算机数值模拟的方法来进行参数的拟合.事实上,我们用McMc方法产生所需要的广义指数分布的随机样本,从而来逼近Bayes估计的未知参数. 通过模拟,我们得到了数据表3.1与表3.2 .由表3.1与表3.2的对比结果我们可以看到,在均方误差(MSE)最小的意义下,由Bayes方法得到的参数α和λ的估计,要明显优于相应的由极大似然方法(MLE)得到的参数估计.

关键词：贝叶斯估计极大似然估计伽玛分布熵损失函数无偏估计不变量估计先验密度函数后验密度函数

Functionalization of Single- and Multi-Walled carbon Nanotubes with cationic Amphiphiles for Plasmid DNA complexation and Transfection

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Nano Research 2009年第8期2卷 638-647页

作者： cyrille Richard Nathalie Mignet céline Largeau Virginie Escriou Michel Bessodes Daniel Scherman Unitéde Pharmacologie chimique et Génétique CNRSUMR 8151ParisF-75270 cedex France INSERM U 640ParisF-75270 cedex France UniversitéParis Descartes Facultédes Sciences Pharmaceutiques et BiologiquesParisF-75270 cedex France ENScP ParisF-75231 cedex France

The possibility of delivering DNA effi ciently to cells represents a crucial issue for the treatment of both genetic and acquired ***,even although the effi ciency of non-viral transfection systems has improved in the last decade,none have yet proven to be suffi ciently effective in *** report herein our results on the functionalization of single-walled carbon nanotubes(SWNT)and multi-walled carbon nanotubes(MWNT)by two cationic amphiphiles(lipid RPR120535 and pyrenyl polyamine),their use for the complexation of plasmid DNA,and their efficiency in transfecting cells in *** experiments have shown that the efficiency of transfection is higher when using SWNT instead of MWNT,and that transfection effi ciency is similar or slightly higher when using nanoplexes(SWNT/lipid RPR120535/DNA)instead of lipoplexes(lipid RPR120535/DNA)and several orders of magnitude higher than that of naked *** study therefore shows both that the transfection is better when using SWNTs and that it is dependent on the nature of the amphiphilic molecules adsorbed on the nanotubes.

关键词： carbon nanotubes amphiphile gene delivery plasmid DNA in vitro

Role of calcium Magnesium Aluminate in carbon-containing Bricks for Steel Ladle

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china's Refractories 2021年第1期30卷 23-30页

作者： GAO Jianying WOHRMEYER christoph DETEUF cyrille Imerys Aluminates(china)co. Ltd.Tianjin 300457China Imerys Aluminates Puteaux 92800France

calcium magnesium aluminate,with the commercial name of MagArmour,is a synthetic material consisting of 70 mass%Al_(2)O_(3),20 mass%MgO and 10 mass%caO,*** is characterized by porous microstructure,intergranular aluminates phases and micro-crystalline *** globally launched in 2017,MagArmour has been successfully applied to various carbon-containing refractories serving for steel refining *** of cases have demonstrated the role of MagArmour in enhancing the service life of carbon containing bricks for ladle *** benefits embody in formation of protective coating on hot surface,relief of drilling corrosion in joint positions,and elimination of grooves or cracks caused by mechanical stress *** addition,MagArmour is effective in protecting graphite from deep oxidization so as to be capable of replacing the metallic or carbide anti-oxidants in carbon-containing bricks *** means of chemical analysis and microstructural dissection,postmortem investigations on the used MgO-c bricks from both metal and slag zones of 120t steel refining ladle were conducted to clarify the working mechanism of *** formation of protective coating on hot face is attributed to the dissolution of micro-crystalline spinel into contacting slag,which changes the slag chemistry so as to enhance *** improvement in corrosion/erosion resistance is highly related to the porous microstructure and dispersive *** well known,evaporation of Mg,Al and SiO,and/or internal migration,occurs in MgO-c bricks at elevated *** gaseous phases are absorbed by MagArmour particles due to the high surface area of porous microstructure and condense as corresponding *** oxides react with the intergranular calcium aluminates forming liquid *** increasing temperature,the liquid phase seeps into the matrix under capillary *** increased liquid amount improves the flexibility of the matrix and thus releases th

关键词： calcium magnesium aluminate MagArmour protective coating flexibility oxidation resistance

Early dynamics in plant community trait responses to a novel, more extreme hydrological gradient

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Journal of Plant Ecology 2019年第2期12卷 327-335页

作者： Andrea Oddershede cyrille Violle Annette Baattrup-Pedersen Jens-christian Svenning christian Damgaard Section for Plant and Insect Ecology Department of BioscienceAarhus UniversityVejlsøvej 25DK-8600 SilkeborgDenmark Section for Ecoinformatics&Biodiversity Department of BioscienceAarhus UniversityNy Munkegade 114DK-8000 Aarhus CDenmark cEFE UMR 5175 CNRS-Universitéde Montpellier-UniversitéPaul-Valéry MontpellierEPHE-1919 route de MendeF-34293 MontpellierCEDEX 5France Section for Stream and Wetland Ecology Department of BioscienceAarhus UniversityVejlsøvej 25DK-8600 SilkeborgDenmark

Aims For temperate regions such as Northern Europe,predicted climate change patterns include an increase in winter precipitation causing increased risk of flooding,whereas periods of droughts will become more frequent in *** aim of this study is to explore vari-ations in plant functional trait distributions along a hydrological gradient spanning from recurrent drought events to recurrent flood-ing-mimicking future precipitation *** The experiment was conducted in a controlled grassland experi-ment over a period of 3 years.A novel and more extreme hydro-logical regime was achieved by manipulating the flow of a nearby stream thereby creating a continuous hydrological gradient from flooding during winter to drought during *** commu-nity responses were recorded along this hydrological ***-weighted trait distribution changes along the gradient were described using null *** functional traits were con-sidered:seed mass,leaf dry matter content(LDMc),leaf area,leaf thickness,specific leaf area(SLA)and *** findings Over time,responses in plant functional traits changed at the community *** the study period consistent changes occurred in the mean trait value of several *** in relatively dry plots became dominated by species with water-conserving life strategies,represented by high seed mass and thick *** contrast,disturbance-resistant species(high leaf dry matter content)became dominant in flooded plots,indicating that persistence to flooding was the most important factor control-ling the functional structure in those ***,a high abundance of small-seeded species in flooded plots likely indicates higher frequency of species with higher dispersal ability through *** conclusion,plant traits are useful for predicting responses to climate change,but abrupt and extreme climate event may cause unexpected responses because they have no analog to previously more sta

关键词： functional diversity trait-environment relationship hydrology extreme events flooding

Detailed Analyses of Nymphea Seeds consumed in the Senegal River Valley

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Food and Nutrition Sciences 2024年第8期15卷 695-700页

作者： Nicolas cyrille Ayessou Michel Bakar Diop Fatou Kiné Gueye césar Bassène Mame Samba Mbaye centre dEtudes sur la Scurit Alimentaire et les Molcules Fonctionnelles (cESAM-REScIF) Universit Cheikh Anta DIOP Dakar Sngal Unit de formation et de Recherche des Sciences Agronomiques de lAquaculture et des Technologies Alimentaires Universit Gaston Berger Saint-Louis Sngal Laboratoire de Botanique-Biodiversit Biologie Vgtale Universit Cheikh Anta Diop Dakar Senegal

Physicochemical investigations were performed on seeds of Nymphea lotus and N. micrantha consumed in the Senegal River valley. They revealed a composition similar to that of cereals. In order to estimate their intrinsic quality, the determination of their amino acid, fatty acid and monosaccharids profiles was done. The results indicate that monosaccharides are represented specifically by saccharose (7%) and glucose (0.67%);a predominance of stearic acid and linoleic acid as unsaturated acids (24.86%);arachidic and palmitic acids as the only saturated acid found (11.12%);a good ratio of unsaturated/saturated acid (2.23);a lack of oleic acid, linoleic, palmitoleic, myristic, caprylic acids;a poor-quality index protein due to low quantity amino acids. Nevertheless, all essential amino acids are present in the seeds. The Nymphea sp grains consumed by the populations around the Senegal River valley offer an interesting nutritional quality linked to fatty acids and carbohydrates.

关键词： Nymphea Seeds composition

The Interest of Endoscopy in the Diagnosis of Fallopian Tubes Diseases at the Yaoundé Gyneco-Obstetric and Pediatric Hospital (Ygoph)

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Open Journal of Obstetrics and Gynecology 2023年第4期13卷 767-774页

作者： cyrille Léger Abega claude cyrille Noa Ndoua Irène Nadine Kouna Tsala Arielle Fonkou Gladys Ngono Ateba Tobie Eric Ntsobe Jean cédric Fouda Rosine Mafoma Pascal Foumane Mother and child center Douala General Hospital Douala Cameroon Department of Gyneco-Obstetrics Faculty of Medicine and Biomedical Sciences University of Yaoundé I Yaoundé Cameroon University of Yaoundé I Yaoundé Cameroon Faculty of Medecine and Pharmaceutical Sciences University of Dschang Dschang Cameroon Garoua General Hospital Garoua Cameroon

Introduction: Fallopian diseases are often implicated in female infertility. Several radiological and surgical explorations have been proposed in order to evaluate the severity of lesions found in utero-adnexal pathology. Among tools that are used to investigate such pathologies, we have ultrasound, hysterosalpingography and endoscopy. But, in many developing countries like cameroon, the usage of endoscopy in gynecology is not yet known by many practicians. The objective of our study was to show the interest of endoscopy in the diagnosis of fallopian tube pathologies. Methodology: We conducted a cross-sectional and descriptive study from March 1st, 2017 to May 31st, 2017 at the Gyneco-Obstetrics and Pediatric department of our Hospital. We included all women who presented infertility and underwent ultrasound, hysterosalpingography (HSG) and endoscopy at the Yaoundé Gyneco-obstetrics Hospital. We analyzed epidemiological parameters, clinics, ultrasound, hysterosalpingography and endoscopic finding. We used cohen’s Kappa test to determine the correlation between HSG/endoscopy and ultrasound/endoscopy in the diagnosis of fallopian tube pathologies. The threshold was significant for a K-value > 0.20. Results: We got a sample of 156 women;the mean age was 32.6 ± 4.5 years. The Secondary infertility dominated in 66.7% of cases;31.1% of women presented a past medical history of sexually transmitted infections and 41.7% did abortions before. Endoscopic lesions were dominated by a fallopian obstruction in 54.5% of cases, 8.3% of adhesions, 33.9% of women presented uterine myomas, 37.8% of ovarian cysts and 1.3% of pelvic endometriosis. The K-values between HSG and endoscopy for distal and proximal tube obstructions were significant with respective thresholds of 0.25 and 0.30. The K-value between ultrasound and endoscopy was not significant with a threshold of 0.015 for the tubal hydrosalpinx. conclusion: Endoscopy assessment appears as the most efficien

关键词： Fallopian Tube Endoscopy Hysterosalpingography Ultrasound

Phytochemical Screening and Assays of Phenolic compounds in Senna occidentalis L. Leaf and Seed Extracts

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Food and Nutrition Sciences 2024年第7期15卷 499-508页

作者： Edmond Antoine Badock Lahat Niang Abdoulaye Dramé célestine Nkounkou-Loumpangou Omar Touré Omar Sokhna Nicolas cyrille Ayessou Mady cissé Ecole Suprieure Polytechnique Laboratoire Eau Energie Environnement et Procds Industriels (LE3PI) Universit Cheikh Anta Diop Dakar Sngal Ecole Suprieure Polytechnique Centre dEtudes sur la Scurit Alimentaire et les Molcules Fonctionnelles (CESAM-RESCIF) Universit Cheikh Anta Diop Dakar Sngal Laboratoire de Valorisation des Produits de la Biomasse Dpartement de Chimie Universit Cheikh Anta Diop de Dakar Dakar Sngal Unit de chimie du Vgtal et de la Vie Facult des Sciences et Techniques Universit Marien NGOUABI Brazzaville Republic of the Congo Laboratoire de chimie Organique et Bio-Organique Dpartement de Chimie Facult des Sciences et Techniques/UCAD Universit Cheikh Anta Diop Dakar Sngal

Phytochemical screening and assay of secondary metabolites, crude extracts with distilled water, aqueous methanol, aqueous acetone and aqueous ethanol of leaves and seeds of Senna occidentalis L. were studied in this work. The aim was to verify the distribution of secondary metabolites according to S. occidentalis organs. Four leaf samples from four different localities (South, East, West and central Senegal) and a mixed sample of seeds were used. Functional molecules such as polyphenols, flavonoids and tannins were then assessed in the leaves and seeds using various standard methods. The results show that Senna occidentalis L. leaf and seed samples display an identical and homogeneous profile, regardless of locality. They contain secondary metabolites and the polyphenol content of extracts from southern, eastern, western and central leaves is: 0.620 - 0.539 - 0.811 - 0.573 g GAE/100 g DM;flavonoids: 0.064 - 0.074 - 0.130 - 0.101 g cE/100 g DM and tannins: 0.326 - 0.264 - 0.269 - 0.494 g TAE/100 g DM. The efficacy of S. occidentalis L. infusions in therapy is thus justified by the presence of these metabolites, whose biological properties are well known. It is then possible to explore isolation of active principles of Senna occidentalis L. leaves and even seeds for producing medicines.

关键词： Senna occidentalis L. Total Polyphenols Flavonoids Tannins

High infection rates for onchocerciasis and soil-transmitted helminthiasis in children under fve not receiving preventive chemotherapy:a bottleneck to elimination

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Infectious Diseases of Poverty 2022年第2期11卷 86-87页

作者： Hugues c.Nana-Djeunga Linda Djune-Yemeli Andre Domche cyrille Donfo-Azafack Arnauld Efon-Ekangouo cedric Lenou-Nanga Narcisse Nzune-Toche Yves Aubin Balog Jean Gabin Bopda Steve Mbickmen-Tchana Velavan P.Tirumalaisamy Veronique Penlap‑Beng Francine Ntoumi Joseph Kamgno centre for Research on Filariasis and other Tropical Diseases(cRFilMT) YaoundeCameroon 不详

Background:The current mainstay for control/elimination of onchocerciasis and soil-transmitted helminthiasis(STH)relies on ivermectin-and mebendazole/albendazole-based preventive ***,children under fve years of age have been excluded in both research activities and control programs,because they were believed to have insignifcant infection *** is therefore a need for up-to-date knowledge on the prevalence and inten‑sity of STH and onchocerciasis infections in this age *** study aimed at assessing the rates and intensities of onchocerciasis and STH infections in children under fve years of age who are excluded from ivermectin-or mebenda‑zole/albendazole-based preventive ***:A series of cross-sectional surveys was conducted in four Health Districts in the centre and Littoral Regions of cameroon between 2018 and *** subjects aged 2 to 4 years,were screened for prevalence(or infection rate)and intensity[number of eggs per gram of stool(epg)or number of microflariae per skin snip(mf/ss)]of STH and onchocerciasis infections respectively using the Kato-Katz and skin snip ***-square and the nonparametric tests(Mann Whitney and Kruskal Wallis)were used to compare infection rates and intensities of infections between Health Districts and genders,***:A total of 421 children were enrolled in this *** overall prevalence of onchocerciasis was 6.6%[95% confdence interval(cI):4.3‒9.9],ranging from 3.6%(in the Ntui Health District)to 12.2%(in the Bafa Health District).The intensity of infection ranged from 0.5 to 46 microflariae per skin snip[median:5;interquartile range(IQR):2.25‒8.5].The overall prevalence of STH was 9.6%(95%cI:6.5‒13.9),with a high infection rate(29.6%)in the Akonolinga Health *** STH species(Ascaris lumbricoides and Trichuris trichiura)were found among infected *** median intensities of STH infections were 1,992 epg(IQR:210‒28,704)and 96 epg(IQR:48‒

关键词： Onchocerciasis Soil-transmitted helminthiasis Preventive chemotherapy children under fve cameroon

Single-chain variable fragment antibody constructs neutralize measles virus infection in vitro and in vivo

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cellular & Molecular Immunology 2021年第7期18卷 1835-1837页

作者： cyrille Mathieu Marion Ferren Olivia Harder Francesca TBovier Tara cMarcink camilla Predella Fabrizio Angius Jennifer Drew-Bear NValerio Dorrello Alex LGreninger Anne Moscona Stefan Niewiesk Branka Horvat Matteo Porotto center for Host-Pathogen Interaction Columbia University Vagelos College of Physicians and SurgeonsNew YorkNYUSA Department of Pediatrics Columbia University Vagelos College of Physicians and SurgeonsNew YorkNYUSA cIRI Centre International de Recherche en InfectiologieTeam IBIVUniv LyonInsermU1111UniversitéClaude Bernard Lyon 1CNRSUMR5308ENS de LyonF-69007LyonFrance Department of Veterinary Biosciences College of Veterinary MedicineThe Ohio State UniversityColumbusOHUSA epartment of Experimental Medicine UniversitàVanvitelliCasertaItaly Department of Laboratory Medicine University of Washington School of MedicineSeattleWAUSA Vaccine and Infectious Disease Division Fred Hutchinson Cancer Research CenterSeattleWAUSA Department of Microbiology&Immunology Columbia University Vagelos College of Physicians and SurgeonsNew YorkNYUSA Department of Physiology&cellular Biophysics Columbia University Vagelos College of Physicians and SurgeonsNew YorkNYUSA

Despite the availability of an effective measles virus(MeV)vaccine and efforts to increase vaccine coverage by the WHO,UNIcEF,and their partners,MeV has not been eradicated,and the estimated global measles death rose from 89,780 in 2016 to 207,500 in 2019.1 Because there is an effective measles vaccine,antiviral development for measles has not been prioritized,but recent outbreaks have highlighted the need for drugs to prevent transmission in unvaccinated populations and to protect and treat immunocompromised *** identified several neutralizing mouse monoclonal antibodies(mAbs)that target the MeV fusion(F)protein in its prefusion state2 and inhibit fusion and viral *** engineered a single-chain variable fragment(scFv)from the most potent anti-MeV F *** scFv retains the ability to inhibit fusion and prevents infection in vitro,and intranasal administration of the scFv antibody construct prevents infection in vivo.

关键词： neutral priori UNIcEF