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基于垂直腔的通信波段短脉冲源

光学与光电技术 2015年第2期13卷 1-4页

作者： jean-louis Oudar 法国国家科学研究院光子学与纳米结构实验室电信应用光子学研究组

基于垂直微腔的光器件为自由空间与光纤中传播的光信号提供了简易的接入方式,极大地降低了器件封装的成本。垂直外腔表面发光激光器(也被称为半导体盘形激光器)结合了固态激光器和半导体激光器的优点,为开发新型紧凑的激光光源提供了新... 详细信息

基于垂直微腔的光器件为自由空间与光纤中传播的光信号提供了简易的接入方式,极大地降低了器件封装的成本。垂直外腔表面发光激光器(也被称为半导体盘形激光器)结合了固态激光器和半导体激光器的优点,为开发新型紧凑的激光光源提供了新方法。对基于垂直腔的短脉冲源的研究现状进行一个简单的综述后,介绍了一些基于1.55μm波长的亚皮秒光脉冲源的最新研究结果。这种脉冲源由InP基的垂直面发射激光器和GaAs基的半导体饱和吸收镜构成。

关键词：短脉冲源锁模激光器半导体光纤通信

Prognosis and Survival of Nasopharyngeal Cancer in Cameroon

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International Journal of Otolaryngology and Head & Neck Surgery 2021年第1期10卷 6-19页

作者： jean Paul Engbang Amadou Njifou Therè se Daphné e Tjomb Maurice Mpessa louis Richard Njock Faculty of Medicine and Pharmaceutical Sciences The University of Douala Douala Cameroon Douala Laquintinie hospital Douala Cameroon

Background: Nasopharyngeal carcinoma (NPC) is an entity belonging to up-per aerodigestive tract Cancers. NPC is more widespread in Southern China and South East Asia. In our country, it is the leading cause of head and neck cancers. Its prognosis remains bleak because of the late stage at diagnostic. Objectives: The objectives of this study were to determine the prognostic fac-tors and survival rate of patients with nasopharyngeal cancer in six reference hospitals in Cameroon. Material and Methods: It was a retrospective analytic study, conducted from January 2009 to December 2018. It was conducted in oncology, surgery and Ear Nose and Throat (ENT) units of six reference hos-pitals. Data from 114 files meeting the inclusion were collected. We have drawn survival curves and determined the different survival probabilities with the help of Kaplan-Meier Method. The different survival curves were compared using the Log-Rank Test (P Results: The mean age at the time of diagnosis of the 114 patients recruited was 45.30 ± 17.14 years. The predominant histological type was the UCNT (Undifferentiated Carcinoma of the NasoPharynx) representing 84.2%. According to the WHO classification, 2 patients were classified as stage I (1.8%), 33 as stage II (28.9%), 42 as stage III (36.8%), 25 as stage IV A (21.9%) and 12 as stage IV B (10.5%). At the end of the survival assessment period, 34 patients were dead and 73 patients (64%) were still alive. The median overall survival was 44 months. The overall survival rates at one, two, three, and four years were 80%;74%;68%;44%, respectively. The prognostic factors associated with poor survival were: late consultation time of more than 12

关键词： Nasopharyngeal Cancer Survival Prognostic Factors Detection Cameroon

Multivariate Asthma Phenotypes in Adults: The Quebec City Case-Control Asthma Cohort

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Open Journal of Respiratory Diseases 2013年第4期3卷 133-142页

作者： émilie Lavoie-Charland jean-Christophe Bérubé Michel Laviolette louis-Philippe Boulet Yohan Bossé Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec Québec City Canada Department of Molecular Medicine Laval University Québec City Canada

Background and Objectives: Asthma is a heterogeneous disease where patient severity can be classified according to various models based on numerous variables. Large collections of well-phenotyped subjects are needed to find distinct clusters of patients for personalized medicine and future genetic studies. The objective of this study is to describe the collection of the Quebec City Case-Control Asthma Cohort and to identify homogeneous subgroups of asthma patients based on clinical characteristics. Methods: This cohort is part of an ongoing project initiated in 2007 to elucidate the genetic basis of asthma. All subjects are randomly recruited at the same site following advertisements. Subjects are unrelated French Canadian white adults 18 years of age or older. Each participant underwent a spirometry, methacholine challenge, and allergy skin-prick tests. Blood was collected for DNA, cell counts and total serum IgE measurements. So far, 982 subjects have been recruited and classified as cases (n = 566) or controls (n = 416). We performed factor and cluster analyses on collected phenotypes from this set to identify subgroups of phenotypically similar asthmatic patients. Results: Factor analysis with 13 variables led to the selection of five factors: lung function, numbers of allergens, blood eosinophil percentage, smoking status and age. K-means cluster analysis on the reduced dataset produced four significantly different groups with the following characteristics: smoking history, low atopy and low lung function, high atopy, and young non-smoking with average atopy. Conclusions: The Quebec City Case-Control Asthma Cohort is a new resource for local and collaborative clinical and genetic research on asthma. This new collection reveals distinct multivariate phenotypes of adult asthma that are likely to be important for future genetic studies and targeted therapies.

关键词： Asthma Phenotypes Mild-Moderate Asthma Cluster Analysis Factor Analysis

The Global Boundary Stratotype Section and Point （GSSP） for the base of the Pliensbachian Stage （Lower Jurassic）, Wine Haven, Yorkshire, UK

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Episodes 2006年第2期29卷 93-106页

作者： Christian Meister Martin Aberhan Joachim Blau jean-louis Dommergues Susanne Feist-Burkhardt Ernie A. Hailwood Malcom Hart Stephen P. Hesselbos Mark W. Hounslow Mark Hylton Nicol Morton Kevin Page Greg D. Price Département de Géologie et de Paléontologie 1 route de Malagnou c.p. 6434 CH-1211 Genève 6 Switzerland Museum der Naturkunde Zentralinstitut der Humboldt-Universitat zu Berlin Institut für Palaiontolgie Invalidenstr. 43 D-10115 Berlin Germany Institut für Geowissenschaften Diezstrasse 15 D-35390 Giessen Germany Centre des Sciences de la Terre de I＇Université de Bourgogne UMR CNRS 5561： Paléontologie analytique et Géologie sédimentaire 6 Boulevard Gabriel F-21100 Dijon. France Department of Palaeontology The Natural History Museum Cromwell Road London SW7 5BD UK Core Magnetics The Green Sedbergh Cumbria LA10 5JS UK Department of Geological Sciences University of Plymouth Drake Circus Plymouth Devon PL4 8AA UK Department of Earth Sciences University of Oxford Parks Road Oxford OXI 3PR UK CEMP Geography Dept. Lancaster Environment Centre Lancaster University Bailrigg Lancaster UK. LA1 4YB Le Chardon Quarrier Brugière F-07200 Vogüé France

Following votes by the Pliensbachian Working Group, the Jurassic Subcommission and the International Commission on Stratigraphy, lUGS ratified the proposed Global Boundary Stratotype Section and Point （GSSP） for the base of the Pliensbachian Stage （Lower Jurassic） at the base of bed 73b in the Wine Haven section, Robin Hood＇s Bay, Yorkshire Coast, UK. This level contains the characteristic ammonite association Bifericeras donovani Dommergues and Meister and Apoderoceras sp. Complementary data include： a） Strontium-isotope stratigraphy, based on analysis of belemnites which yield a calcite 87Sr/^86Sr ratio for the boundary level of 0. 707425 and data supporting interpretation of continuous sedimentation; b） Belemnite oxygen-isotope data indicate a significant temperature drop （-5 ℃） across the boundary at this locality; c） A Transgressive Systems Tract （TST） initiated in the Aplanaturn Subzone （uppermost Sinemurian） continues into the Lowermost Pliensbachian （Taylori Subzone）; it forms part of a transgressive facies cycle sensu Graciansky et al. （1998）; d） The Upper Sinemurian to lowermost Plensbachian at Wine Haven section has a predominantly norreal magnetic polarity, but two discrete reversed polarity magnetozones are present. The first spans much of the latest Sinemurian Aplanatum Subzone. It terminates 〈0.5m below the Sinemurian-Pliensbachian boundary and may prove a valuable chronostratigraphic marker The second extends from the latest Oxynotum Subzone probably through to the lower part of the Raricostatum Subzone.

关键词：普连斯巴奇阶侏罗纪 GSSP 全球界线层型剖面点

Vitamin and Osidic Composition of Table Sugars from the Inflorescences Sap of 03 Coconut Cultivars (<i>Cocos nucifera</i>L.) in Ivory Coast

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Food and Nutrition Sciences 2020年第12期11卷 1117-1126页

作者： D. Muriel J. Okoma K. jean louis Konan Rebecca R. Assa Marc Delorme Research Station for Coconut National Centre of Agronomic Research (CNRA) Abidjan C&#244 te d’Ivoire Laboratory of Biochemistry and Food Sciences UFR Biosciences University Felix Houphou&#235 t Boigny Abidjan C&#244 te d’Ivoire

In order to revalorize the nucicultural sector in Ivory Coast, initiatives have been taken to diversify the uses of coconut through the production of sugar from its inflorescences. Four water-soluble vitamins have been determined in the crystalline sugar of coconuts. These are vitamins C, B1, B2 and B6. On the other hand, no vitamin was identified in cane sugars. Vitamin C is the most abundant in coconut sugar. The oses contained in coconut sugar are saccharose, glucose and fructose. Sucrose is the main constituent of coconut crystal sugar. Thanks to their sweetening power close to saccharose, the coconut sugars produced can be used as sweetening ingredients in pastries, confectionery, drinks and culinary preparations. Their richness in vitamin C makes them a food that can stimulate the body’s natural and immune defences.

关键词： Coconut Sugar Vitamins Oses

A Push–Pull Mechanism Helps Design Highly Competent G-Quadruplex-DNA Catalysts

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CCS Chemistry 2021年第8期3卷 2183-2193页

作者： Jielin Chen Jiawei Wang Stephanie C.Cvan der Lubbe Mingpan Cheng Dehui Qiu David Monchaud jean-louis Mergny Célia Fonseca Guerra Huangxian Ju Jun Zhou State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023 Theoretical Chemistry Department of Chemistry and Pharmaceutical SciencesAIMMSVrije Universiteit AmsterdamAmsterdam 1081 HV Institut de Chimie Moléculaire(ICMUB) CNRSUniversitéde Bourgogne Franche-ComtéDijon 21078 Leiden Institute of Chemistry Gorlaeus LaboratoriesLeiden UniversityLeiden 2333 CD

Massive efforts are currently being invested to improve the performance,versatility,and scope of applications of nucleic acid catalysts.G-quadruplex(G4)/hemin DNAzymes are of particular interest owing to their structural programmability and chemical ***,optimized catalytic efficiency is still bottleneck and the activation mechanism is ***,we have designed a series of parallel G4s with different proximal cytosine(dC)derivatives to fine-tune the hemin-binding pocket for G4-DNAzymes.

关键词： DNAzyme electron density G-quadruplex hemin push–pull mechanism

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利用三维几何矩在核磁图象中定量检测血管

科学通报 1994年第4期39卷 372-375页

作者：罗立民谢筱华鲍旭东 jean-louis Coatrieux 东南大学生物科学与医学工程系图象研究室南京210018 LTSI University of Rennes-I RennesFrance

三维定量分析人体血管结构在临床诊断中十分重要.常规的X线方法存在一些不足,如需要注入血管造影剂,并在之前后采集两幅图象,除患者必须承受较大剂量的X线外,前后两幅图象还存在着由于病人体动而引起的偏移,因而还需要进行校正处理.另外... 详细信息

三维定量分析人体血管结构在临床诊断中十分重要.常规的X线方法存在一些不足,如需要注入血管造影剂,并在之前后采集两幅图象,除患者必须承受较大剂量的X线外,前后两幅图象还存在着由于病人体动而引起的偏移,因而还需要进行校正处理.另外,为了从血管造影的二维数据获取三维结构,还必须进行一系列的重建处理.核磁成象技术可以直接获取三维图象数据,它所获取的三维图象数据中的血管结构具有较好的对比度,因此可以从中直接提取出血管的三维结构.

关键词：血管矩定量检测

Apoptosis in rat transient focal cerebral ischemic stroke:clinical implications

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中国临床神经科学 2000年第Z1期8卷 18-19页

作者： Shoushu Jiao Jue Wang Gal Hever Rongzheng Kuang jean-Claude louis Ella Magal Department of Neuroscience AmgenInc.One Amgen Center Dr.Thousand OaksCalifornia91320USA

In the early phase of cerebral ischemia,factors threatening neuronal survival in the penumbra include mainly glutamate excitotoxicity,free radical damage and energy failure resulting from recurrent depolarization ***,at later times,other mechanisms come into *** initial ischemic event activates a variety of genetic programs that unfold over the course of hours and *** positron emission tomography and magnetic resonance based techniques demonstrate that the development of irretrievable tissue damage is relatively slow,progressing over the course of several days in some cases,and a viable tissue,defined by hemodynamic and metabolic criteria,is still present many hours after stroke in human or in *** findings suggest that the brain can potentially be“rescued”from infarction many hours after onset of ischemia and challenge the widespread notion of an early and short“therapeutic window”(~3-6h).This realization is of critical importance for stroke therapy because most patients reach medical attention at a time when current therapeutic strategies may no longer be ***,it would be highly desirable to develop therapeutic interventions that can be instituted many hours after the onset of *** believe that addressing the mechanisms of delayed cell death is key to a successful *** studies presented here were designed to document the potential contribution of apoptosis to ischemia induced neuronal *** will discuss the morphological,biochemical and pharmacological evidence for apoptosis in the ischemic stroke.

关键词： positron emission tomography magnetic resonance cerebral ischemia ischemic stroke neuronal death cell death

The economic impact of schistosomiasis

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Infectious Diseases of Poverty 2021年第6期10卷 106-106页

作者： Daniele Rinaldo Javier Perez‑Saez Penelope Vounatsou Jürg Utzinger jean-louis Arcand Department of Economics and Land EnvironmentEconomics and Policy Institute(LEEP)University of ExeterExeterEngland 不详

Background:The economic impact of schistosomiasis and the underlying tradeofs between water resources devel‑opment and public health concerns have yet to be *** exerts large health,social and fnan‑cial burdens on infected individuals and *** irrigation schemes are one of the most important policy responses designed to reduce poverty,particularly in sub-Saharan Africa,they facilitate the propagation of schistoso‑miasis and other ***:We estimate the economic impact of schistosomiasis in Burkina Faso via its efect on agricultural produc‑*** create an original dataset that combines detailed household and agricultural surveys with high-resolution geo-statistical disease *** develop new methods that use the densities of the intermediate host snails of schis‑tosomiasis as instrumental variables together with panel,spatial and machine learning ***:We estimate that the elimination of schistosomiasis in Burkina Faso would increase average crop yields by around 7%,rising to 32%for high infection *** schistosomiasis unchecked,in turn,would correspond to a loss of gross domestic product of approximately 0.8%.We identify the disease burden as a shock to the agricultural productivity of *** poorest households engaged in subsistence agriculture bear a far heavier disease burden than their wealthier counterparts,experiencing an average yield loss due to schistosomiasis of between 32 and 45%.We show that the returns to water resources development are substantially reduced once its health efects are taken into account:villages in proximity of large-scale dams sufer an average yield loss of around 20%,and this burden decreases as distance between dams and villages ***:This study provides a rigorous estimation of how schistosomiasis afects agricultural production and how it is both a driver and a consequence of *** further quantifes the tradeof between the economics of wa

关键词： Schistosomiasis Neglected Tropical Diseases Sub-Saharan Africa Agriculture Water Resources Development Poverty