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Variation of Stable Isotopes in Surface Snow along a Traverse from Coast to Plateau's interior in East Antarctica and Its Climatic Significance

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Research in Cold and Arid Regions 2009年第1期1卷 14-24页

作者： jean Jouzel michel Stievenard Institut Pierre Simon Laplace/Laboratoire des Sciences du Climat et de l'Environnement CEA-CNRS-University Versailles-Saint Quentin

The variations of stable water isotopes of surface snow in east Antarctic Ice Sheet, are discussed by a total of 251 samples, which were taken along a 330 km traverse from Zhongshan Station to the outer edge of the Antarctic plateau and from four snow pits excavated along the route. Analyzing results of the samples showed the expected linear relationship between the parameters ?D and ?18O with slope S1 and intercept d1. When the data set was examined using a sliding window with a width of 5 samples, it was found that there were two areas with different ratios of S1 and d1. The boundary between these two areas occurred at an elevation of about 2,000 m, suggesting two different sources of water vapour. Nearly half (47%) of the fresh-snow samples had negative deuterium excess (d=?D? 8?18O) values, but few of the snow pit samples did, suggesting that variations of ? are quickly smoothed by isotopic diffusion in the near-surface firn. Analysis of the phase relationship between ?D and deuterium excess in the snow pit stratigraphies showed that they were mostly in phase from Jan. 1994 to Sept. 1995, but mostly out of phase from Sept. 1995 to Jan. 1997.

关键词： east Antarctica ice sheet stable isotopes snow

Prokineticin 2/Bv8 is expressed in Kupffer cells in liver and is down regulated in human hepatocellular carcinoma

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World Journal of Gastroenterology 2008年第8期14卷 1182-1191页

作者： Justin Monnier Claire Piquet-Pellorce jean-Jacques Feige Orlando Musso Bruno Clément Bruno Turlin Nathalie Théret michel Samson INSERM U620 Université de Rennes 1 IFR140 2 avenue du Pr. Léon Bernard Rennes cedex 35043 France INSERM U522 Rennes France INSERM U878 Grenoble France Service d'Anatomo-pathologie CHU Pontchaillou Rennes France

AIM： TO study the implication of prokineticin 1 （PKI/EGVEGF） and prokineticin 2 （PK2/13v8） in hepatocellular carcinoma angiogenesis.METHODS： The gene induction of PK1/EG-VEGF and PK2/Bv8 was investigated in 10 normal, 28 fibrotic and 28 tumoral livers by using real time PCR. Their expression was compared to the expression of VEGF （an angiogenesis marker）, vWF （an endothelial cell marker） and to CD68 （a monocyte/macrophage marker）. Furthermore, the rnRNA levels of PK1/EG-VEGF, PK2/Bv8, prokineticin receptor 1 and 2 were evaluated by real time PCR in isolated liver cell populations. Finally, PK2/Bv8 protein was detected in normal liver paraffin sections and in isolated liver cells by immunohistochernistry and immunocytochemistry.RESULTS： PK2/Bv8 mRNA but not PK1/EG-VEGF was expressed in all types of normal liver samples examined. In the context of liver tumor development, we reported that PK2/13v8 correlates only with CD68 and showed a significant decrease in expression as the pathology evolves towards cancer. Whereas, VEGF and vWF mRNA were significantly upregulated in both fibrosis and HCC,as expected. In addition, out of all isolated liver cells examined, only Kupffer cells （liver resident macrophages） express significant levels of PK2/Bv8 and its receptors, prokineticin receptor 1 and 2.CONCLUSION： In normal liver PK2/Bv8 and its receptors were specifically expressed by Kupffer cells. PK2/Bv8 expression decreased as the liver evolves towards cancer and did not correlate with HCC angiogenesis.

关键词： Prokineticin Hepatocellular carcinoma PK2/Bv8 Angiogenesis Kupffer cells Vascular endothelial growth factor Liver

Topological to trivial insulating phase transition in stanene

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Nano Research 2016年第3期9卷 774-778页

作者： michel Houssa Bas van den Broek Konstantina Iordanidou Anh Khoa Augustin Lu Geoffrey Pourtois jean-Pierre Locquet Valery Afanas'ev Andre Stesmans Department of Physics and Astronomy University of Leuven Celestijnenlaan 200D B-3001 Leuven Belgium imec 75 Kapeldreef B-3001 Leuven Belgium

Electronic properties of stanene, the Sn counterpart of graphene are theoretically studied using first-principles simulations. The topological to trivial insulating phase transition induced by an out-of-plane electric field or by quantum confinement effects is predicted. The results highlight the potential to use stanene nanoribbons in gate-voltage controlled dissipationless spin-based devices and are used to set the minimal nanoribbon width for such devices, which is typically approximately 5 nm.

关键词： two-dimensional (2D)materials topological insulators density functional theory(DFT) simulations electronic structure

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稀释燃烧的火焰稳定性

燃烧科学与技术 2009年第2期15卷 103-108页

作者：刘玉英 MOST jean-michel BAUER Philippe 杨茂林北京航空航天大学能源与动力工程学院北京100083 法国国家科学研究中心燃烧与爆炸实验室普瓦捷86961法国

采用实验研究的方法探讨了反应物预热温度与稀释率两个因素对稀释燃烧火焰稳定性的影响.实验以氮气稀释的甲烷-空气对冲扩散火焰为研究对象,确定了不同反应物预热温度与氧化剂稀释率(氧气体积分数)时火焰的熄火极限,结果表明,增大反应... 详细信息

采用实验研究的方法探讨了反应物预热温度与稀释率两个因素对稀释燃烧火焰稳定性的影响.实验以氮气稀释的甲烷-空气对冲扩散火焰为研究对象,确定了不同反应物预热温度与氧化剂稀释率(氧气体积分数)时火焰的熄火极限,结果表明,增大反应物预热温度拓宽了火焰稳定燃烧区域,而增加氧化剂稀释率(降低氧气体积分数)会降低稀释火焰的稳定性,二者对火焰稳定性的影响作用相反.为了进一步分析反应物预热温度与稀释率对火焰稳定性的影响程度,引入了估算的Damk hler数,分析表明,在实验研究范围内,反应物预热温度对火焰稳定性的影响比稀释率的影响显著,是火焰稳定性的主要影响因素.

关键词：对冲火焰稀释燃烧稳定性熄火极限

Is There an Earthquake Weather?

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Open Journal of Earthquake Research 2020年第2期9卷 69-82页

作者： michel Parrot jean-Louis Pincon LPC2E CNRSOrleansFrance University of Orleans OrleansFrance

The aim of this study is to check if there is a relationship between the seismic activity and the whistlers observed by the micro-satellite DEMETER. Whistlers are the waves emitted by lightning strokes during thunderstorm activity. They use to propagate in the Earth-ionosphere waveguide but also in the ionosphere and the magnetosphere mainly along the magnetic field lines. Due to this reason we have checked the whistler occurrence not close to earthquake epicenters but close to the magnetically conjugate point of these epicenters at the satellite altitude. The number of whistlers is given by a neural network in operation onboard the satellite. It appears that the whistler amplitude is attenuated at the satellite altitude around the magnetic equator. It is why we have removed the earthquakes occurring at low geomagnetic latitudes in the statistic. The whistler rate is normalized with a background value to take into account the seasons and the epicenter locations. A superposed epoch method is used to display the results between -15 and +5 days around the earthquake day and up to 1000 km from the conjugate point of the epicenters. It is shown that the whistler rate is higher the day before the earthquake at a distance less than 200 km. It would be unrealistic to believe in the possibility to use this study for earthquake prediction because everyday thunderstorm activity reliably masks seismic effects. But it is further evidence that there is a lithosphere-atmosphere-ionosphere coupling at the time of the seismic activity.

关键词： Data Processing Earthquake Whistler Ionosphere

Two-and Three-Dimensional Urban Core Determinants of the Urban Heat Island： A Statistical Approach

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Journal of Environmental Science and Engineering(B) 2012年第3期1卷 363-378页

作者： Bumseok Chun jean-michel Guldmann Department of City and Regional Planning The Ohio State University Columbus Ohio 43210 USA

There is no doubt that the UHI （urban heat island） is a mounting problem in built-up environments, due to the energy retention by surface dense building materials, leading to increased temperatures, air pollution, and energy consumption. Much of the earlier research on the UHI has used two-dimensional （2-D） information, such as land uses and the distribution of vegetation. In the case of homogeneous land uses, it is possible to predict surface temperatures with reasonable accuracy with 2-D information. However, three-dimensional （3-D） information is necessary to analyze more complex sites, including dense building clusters. In this research, 3-D building geometry information is combined with 2-D urban surface information to examine the relationship between urban characteristics and temperature. The research includes the following stages：（1） estimating urban temperature; （2） developing a 3-D city model; （3） generating geometric parameters; and （4） conducting statistical analyses using both linear and non-linear regression models. The implications of the results are discussed, providing guidelines for policies aiming to reduce the UHI.

关键词： Urban heat island urban morphology three-dimensional city model geographic information system.

Efficacy and safety profile of LCR35 complete freeze-dried culture in irritable bowel syndrome:A randomized,double-blind study

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World Journal of Gastroenterology 2012年第17期18卷 2067-2075页

作者： michel Dapoigny Thierry Piche Philippe Ducrotte Bernard Lunaud jean-michel Cardot Annick Bernalier-Donadille Médecine Digestive Centre Hospitalier Universitaire(CHU) Estaing CHU Clermont-FerrandClermont UniversitéInserm UMR 76663001 F-Clermont-FerrandFrance Department of Gastroenterology and Inserm 576 Hpital de l'Archet 206202 NiceCedex 3France Department of Hepatogastroenterology and Nutrition Hpital Charles NicolleInserm UMR 107376031 RouenCedexFrance Department of Gastroenterology Centre République63000 Clermont-FerrandFrance Biopharmacy Department Faculty of Pharmacy63000 Clermont-FerrandFrance UR454 Microbiology Division Institut National de la Recherche AgronomiqueResearch Centre of Clermont-Ferrand-Theix63122 Saint Genès-ChampanelleFrance

AIM:To assess the effects and safety of Lactobacillus casei rhamnosus LCR35 complete freeze-dried culture(LCR35) in patients suffering from irritable bowel syndrome(IBS).METHODS:A randomized,double-blind pilot study was performed in 50 patients complaining of IBS symptoms complying with RomeⅢ*** were allocated to receive either LCR35(n = 25) at a minimum daily dose of 6 × 108 colony forming units or placebo(n = 25) for 4 *** inclusion,after treatment and 2 wk later,patients completed the IBS severity *** from baseline in the IBS severity score at the end of treatment was the primary efficacy *** were compared between groups in the whole population and in IBS subtypes(IBS with predominance of constipation,IBS with predominance of diarrhoea,mixed IBS,unsubtyped IBS).The presence of lactobacillus casei rhamnosus in stools was investigated at inclusion and at the end of *** gastrointestinal quality of life questionnaire and the hospital anxiety and depression(HAD) scale were also ***:Both groups were balanced for baseline *** 85% of patients,stool analyses showed that lactobacillus casei rhamnosus able to survive in the digestive *** the whole population,improvements in the IBS severity score did not differ significantly between treatments with a 25% decrease after 4-wk treatment,and a 15% decrease from baseline 2 wk later in both *** IBS subgroups,statistical analysis could not be performed due to small sample size,but a clinical response in favour of LCR35 was observed in IBS patients with predominance of diarrhoea:no change in the symptom severity score was seen with the placebo after 4 wk treatment,whereas a clinically relevant decrease occurred with LCR35(-37% vs-3%).Furthermore,in spite of an increase in symptom intensity,the IBS severity score was maintained below the baseline value 2 wk later with LCR35(-19% from baseline),whilst a slight 5% increase from baseline was observ

关键词： Irritable bowel syndrome Lactobacillus casei rhamnosus Probiotics Symptom severity score

Rural Wireless Mesh Network: A Design Methodology

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International Journal of Communications, Network and System Sciences 2015年第1期8卷 1-9页

作者： jean Louis Ebongue Kedieng Fendji jean michel Nlong University Institute of Technology (UIT) The University of Ngaoundéré Ngaoundéré Cameroon Faculty of Science The University of Ngaoundéré Ngaoundéré Cameroon

Wireless Mesh Network is presented as an appealing solution for bridging the digital divide between developed and under-developed regions. But the planning and deployment of these networks are not just a technical matter, since the success depends on many other factors tied to the related region. Although we observe some deployments, to ensure usefulness and sustainability, there is still a need of concrete design process model and proper network planning approach for rural regions, especially in Sub-Saharan Africa. This paper presents a design methodology to provide network connectivity from a landline node in a rural region at very low cost. We propose a methodology composed of ten steps, starting by a deep analysis of the region in order to identify relevant constraints and useful applications to sustain local activities and communication. Approach for planning the physical architecture of the network is based on an indoor-outdoor deployment for reducing the overall cost of the network.

关键词： Design Methodology Planning Rural Regions Wireless Mesh Network

Exploring the Impact of Crisis and Trauma on the Mental Health and Psychological Well-Being of University Students in Northern Haiti

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International Journal of Mental Health Promotion 2023年第2期25卷 173-191页

作者： Michael Galvin Guesly michel Henri-Claude Saintelmond Carolyn Lesorogol jean-François Trani Lora Iannotti Harvard University Cambridge02138USA Boston University Boston02215USA Centre de SantéMental de Morne Pelé Cap-Haïtien2697Haiti UniversitéPublique du Nord au Cap-Haïtien Cap-Haïtien2697Haiti Washington University in St.Louis St.Louis63130USA

In recent decades,Haiti has been subject to man-made and natural disasters that have left its citizens vulnerable to a range of *** a weak state unable to protect its populace,Haitians are exposed to some of the highest levels of poverty and violence in the Western *** recent years,Haitians have experienced two crises that this study analyzes:the instability and political violence of“peyi lòk”as well as the global pandemic of *** community-based assessment explores the impact of these two crises on the mental health and psychological well-being of 38 Haitian university students in the understudied northern part of the *** indicate that both crises had similarities related to their psychological effects on young people,most notably in terms of traumatic experiences related to threats or violence,forced confinement,and large increases in population-wide ***,the extreme violence of“peyi lòk”and the widespread unpredictability of COVID-19 and its effects in the early days of the pandemic resulted in high levels of stress and *** crises also resulted in extreme economic hardship for students,with many reporting difficulties accessing basic needs such as food and *** study highlights how converging population-level crises in“complex emergencies”can heighten trauma and compromise mental health.

关键词： Haiti crisis mental health psychological well-being coronavirus COVID-19