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Anomalous transport of light at the phase transition to localization:strong dependence with incident angle

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Photonics Research 2018年第10期 55-68页

作者： IPEN M.c.S.XAVIER IPEN VALDEcI MESTRE WELITON S.MARTINS gABRIEL f.BASSO V.A.ERMAKOV f.c.MARQUES gILBERTO f.DE S Instituto de Pesquisas Energéticas e Nucleares cNEN Departamento de f?′sica Universidade Federal da Para?′ba Departamento de f?′sica Universidade Estadual da Para?′ba 4. Instituto de Pesquisas Energéticas e Nucleares CNEN 5. CCEA Universidade Estadual da Para?′ba 6. Departamento de F?′sica Universidade Federal Rural de Pernambuco 7. Departamento de Informática Universidade Federal da Para?′ba 8. Departamento de F?′sica Aplicada Universidade Estadual de Campinas 9. Qu?′mica Fundamental Universidade Federal de Pernambuco

There has been a growing interest in disordered optical media in recent years due to their potential applications in solar collectors, random lasers, light confinement, and other advanced photonic functions. This paper studies the transport of light for different incidence angles in a strongly disordered optical medium composed of core-shell TiO@Silica nanoparticles suspended in an ethanol solution. A decrease of optical conductance and an increase of absorption near the input border are reported when the incidence angle increases. The specular reflection, measured for the photons that enter the sample, is lower than the effective internal reflection undergone by the coherently backscattered photons in the exact opposite direction, indicating a nonreciprocal propagation of *** study represents a novel approach in order to understand the complex physics involved at the phase transition to localization.

关键词： der exp Anomalous transport of light at the phase transition to localization:strong dependence with incident angle

School,Museum and University:A New Synergy in Science Education

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地学前缘 2009年第S1期16卷 118-119页

作者： Bruno filipe c.B.Silva Ribeiro A.Neves J.cascalho R.Barata T.Antunes f.Serralheiro Department of Mineralogy and geology National Natural History Museum Department of Botany National Natural History Museum Department of Zoology and Anthropology National Natural History Museum

In the last couple of years the Museum developed a project financed by the National Agency for culture and Technology in partnership with four schools from *** guidelines of this project were the climate change and its influence on human lives in our society and on other living beings."changing climate, changing lives",our project,evolved 8 months work of about 150 high school grade students,in which

关键词： climate change school university museum science education

A 3D Human Liver Model of Nonalcoholic Steatohepatitis

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Journal of clinical and Translational Hepatology 2020年第4期8卷 359-370页

作者： Marion Duriez Agnes Jacquet Lucile Hoet Sandrine Roche Marie-Dominique Bock corinne Rocher gilles Haussy Xavier Vigé Zsolt Bocskei Tamara Slavnic Valérie Martin Jean-claude guillemot Michel Didier Aimo Kannt cécile Orsini Vincent Mikol Anne-céline Le fèvre Translational Sciences Sanofi1 Avenue Pierre BrossoletteChilly-MazarinFrance IT&M STATS Groupe IT&MNeuilly-sur-SeineFrance Non clinical Biostatistics SanofiVitry sur SeineFrance Diabetes and cardiovascular Research SanofiIndustriepark HöchstFrankfurtGermany Institute of Experimental Pharmacology Medical Faculty MannheimUniversity of HeidelbergMannheimGermany

Background and Aims: To better understand nonalcoholic steatohepatitis (NASH) disease progression and to evaluate drug targets and compound activity, we undertook the devel-opment of an in vitro 3D model to mimic liver architecture and the NASH environment. Methods:We have developed an in vitro preclinical 3D NASH model by coculturing primary hu-man hepatocytes, human stellate cells, liver endothelial cells and Kupffer cells embedded in a hydrogel of rat collagen on a 96-well plate. A NASH-like environment was induced by ad-dition of medium containing free fatty acids and tumor ne-crosis factor-α. This model was then characterized by biochemical, imaging and transcriptomics analyses. Results:We succeeded in defining suitable culture conditions to main-tain the 3D coculture for up to 10 days in vitro, with the lowest level of steatosis and reproducible low level of inflammation and fibrosis. NASH disease was induced with a custom me-dium mimicking NASH features. The cell model exhibited the key NASH disease phenotypes of hepatocyte injury, steatosis, inflammation, and fibrosis. Hepatocyte injury was highlighted by a decrease of cYP3A4 expression and activity, without loss of viability up to day 10. Moreover, the model was able to stimulate a stable inflammatory and early fibrotic environ-ment, with expression and secretion of several cytokines. A global gene expression analysis confirmed the NASH induc-tion. conclusions:This is a new in vitro model of NASH dis-ease consisting of four human primary cell-types that exhibits most features of the disease. The 10-day cell viability and cost effectiveness of the model make it suitable for medium throughput drug screening and provide attractive avenues to better understand disease physiology and to identify and characterize new drug targets.

关键词： 3D liver model Human primary cells Key features of NASH

Pneumocystis jiroveci pneumonia and pneumomediastinum in an anti-TNfαnaive patient with ulcerative colitis

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World Journal of gastroenterology 2009年第15期15卷 1897-1900页

作者： James c Lee Deborah c Bell Richard M guinness Tariq Ahmad Department of gastroenterology Royal Devon and Exeter Hospital

We report the case of a 21-year-old man who was noted to have pneumomediastinum during an admission for an acute flare of ulcerative colitis. At that time, he was on maintenance treatment with azathioprine at a dose of 2.25 mg/kg per day, and had not received supplementary steroids for 9 mo. He had never received anti-tumor necrosis factor （TNf）α therapy. Shortly after apparently effective treatment with intravenous steroids and an increased dose of azathioprine, he developed worsening colitic and new respiratory symptoms, and was diagnosed with Pneumocystis jiroveci （carinii） pneumonia （PcP）. Pneumomediastinum is rare in immunocompetent hosts, but is a recognized complication of PcP in human immunodeficiency virus （HIV） patients, although our patient＇s HIV test was negative. Treatment of PcP with co-trimoxazole resulted in resolution of both respiratory and gastrointestinal symptoms, without the need to increase the steroid dose. There is increasing vigilance for opportunistic infections in patients with inflammatory bowel disease following the advent of anti-TNfα therapy. This case emphasizes the importance of considering the possibility of such infections in all patients with inflammatory bowel disease, irrespective of the immunosuppressants they receive, and highlights the potential of steroid-responsive opportunistic infections to mimic worsening colitic symptoms in patients with ulcerative colitis.

关键词： Pneumocystis jiroveci Ulcerative colitis Pneumomediastinum Azathioprine corticosteroids

为设计和规划提供信息的绿色屋顶雨水滞留关键气象因素识别

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城市规划学刊 2015年第5期 125-126页

作者： WONg g K L JIM c Y

传统的城市开发替代自然透水地表,改变了自然的水文循环,导致了渗透、蒸发和地下水回灌从根本上的减少,从而引发城市热岛效应和暴雨内涝灾害。在可持续城市雨水管理的框架下,可持续城市排水系统、低冲击开发以及水敏性城市设计为城市设... 详细信息

传统的城市开发替代自然透水地表,改变了自然的水文循环,导致了渗透、蒸发和地下水回灌从根本上的减少,从而引发城市热岛效应和暴雨内涝灾害。在可持续城市雨水管理的框架下,可持续城市排水系统、低冲击开发以及水敏性城市设计为城市设计和规划提供了新的策略。近年来,绿色屋顶因其多重生态系统服务功能而得到越来越多的关注,其中最重要的生态系统服务功能这一即是提供可持续雨水控制,用屋顶这种看起来没有得到利用的城市表面用于恢复开发前的渗透和保存等水文功能。雨水滞留是绿色屋顶所能提供的重要水文服务

关键词：绿色屋顶气象因素雨水排水层规划长远计划

Phase Transformation under continuous cooling conditions in Medium carbon Microalloyed Steels

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Journal of Materials Science & Technology 2014年第5期30卷 511-516页

作者： Manuel gomez Lucia Rancel Esther Escudero Sebastian f.Medina National centre for Metallurgical Research CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain

Several 35crMo4 and 38MnV7 steels with different additions of Ti and V were manufactured by electroslag remelting. The influence of the alloying and microalloying elements on phase transformation at different cooling rates was studied and the continuous cooling transformation diagrams were plotted. In order to optimize the heat treatment and improve the mechanical properties, the range of cooling rates leading to a fully bainitic microstructure （without ferrite, pearlite and especially without martensite） was determined. Bainite and martensite transformation start temperatures （Bs, Ms） were also established and compared with the values predicted by empirical equations. The important role of precipitates （especially V carbonitride particles） on final microstructure and mechanical properties was assessed.

关键词： Microalloyed steel Phase transformation Precipitation Dilatometry continuous cooling transformation diagram

crystal-oriented wrinkles with origami-type junctions in few-layer hexagonal boron nitride

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Nano Research 2015年第5期8卷 1680-1688页

作者： camilla K. Oliveira Egleidson f. A. gomes Mariana c. Prado Thonimar V. Alencar Regiane Nascimento Leandro M. Malard Ronaldo J. c. Batista Alan B. de Oliveira Helio chacham Ana M. de Paula Bernardo R, A. Neves Departamento de fisica ICEx Universidade Federal de Minas Gerais - UFMG C.P. 702 30123-970 - Belo Horizonte Brazil Departamento de fisica ICEB Universidade Federal de Ouro Preto - UFOP 35400-000 - Ouro Preto Brazil

Understanding layer interplay is the key to utilizing layered heterostructures formed by the stacking of different two-dimensional materials for device applications. Boron nitride has been demonstrated to be an ideal substrate on which to build graphene devices with improved mobilities. Here we present studies on the morphology and optical response of annealed few-layer hexagonal boron nitride flakes deposited on a silicon substrate that reveal the formation of linear wrinkles along well-defined crystallographic directions. The wrinkles formed a network of primarily threefold and occasionally fourfold origami-type junctions throughout the sample, and all threefold junctions and wrinkles formed along the armchair crystallographic direction. furthermore, molecular dynamics simulations yielded, through spontaneous symmetry breaking, wrinkle junction morphologies that are consistent with both the experimental results and the proposed origami-folding model. Our findings indicate that this morphology may be a general feature of several two-dimensional materials under proper stress-strain conditions, resulting in direct consequences in device strain engineering.

关键词： hexagonal boron nitride 2D materials wrinkles origami folding annealing

fixed Point Theorems of Hegedus contraction Mapping in Some Types of Distance Spaces

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International Journal of Modern Nonlinear Theory and Application 2012年第3期1卷 93-96页

作者： M. A. Ahmed f. M. Zeyada g. f. Hassan Department of Mathematics Faculty of Science Assiut University Assiut Egypt

In the present paper, we prove some fixed point theorems of Hegedus contraction in some types of distance spaces, dislocated metric space, left dislocated metric space, right dislocated metric space and dislocated qua... 详细信息

关键词： Distance Space Dislocated Metric Spaces Quasi-Metric Spaces Dislocated Quasi-Metric Spaces contraction

Synthesis and Magnetic Properties of Nanoparticles of fe-co Alloys and Their Oxides Prepared by chemical Vapor condensation

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Journal of Materials Science & Technology 2004年第4期20卷 459-462页

作者： ZhenhuaWANg ZhidongZHANg c.J.choi B.K.Kim J.c.Kim ShenyangNationalLaboratoryforMaterialsScienceandInternationalcentreforMateri~alsPhysics InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China KoreaInstituteofMachineryandMaterials 66Sangnam-DongChangwonKyungnam641-010Korea

Nanoparticles of fe-co alloys and their oxides with the particle size below 20 nm were prepared by chemical vapor condensation process. The pure Ar, Ar+1%O2, Ar+3%O2 and Ar+6%O2 were used as carrier gases, with iron carbonyl and cobalt carbonyl as the precursors. XRD patterns showed that fe-co metallic nanoparticles were synthesized by using pure Ar as carrier gas, and only metal oxides were obtained using Ar+(>3)%O2 as carrier gas. The HRTEM images and Tg-DTA curves were used to study the core-shell structure of the different nanoparticles. The nanoparticles obtained in pure Ar consist of black core and light shell with thickness of 2~4 nm. However, in the particles obtained in Ar+6%02, the oxides core with visible lattice fringes are surrounded by thin shell.

关键词： fe-co Nanoparticles HRTEM cVc