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伽利略空间和地面段定义：系统和性能

控制工程（北京） 2006年第4期 59-64页

作者： Rafael Lucas joerg. Hahn Simon Dinwiddy Manfred Lugert Guliano Gatti Javier Benedicto 王殿佑（译）潘科炎（校）

1999年，欧洲委员会（EC）和欧洲空间局（ESA）开始了“伽利略”系统的定义阶段。按计划“伽利略”系统是在民航控制下的全球卫星导航系统，为全球提供卫星导航和授时服务。早在“伽利略”系统的定义阶段，EC和ESA就已开展了一系列的市... 详细信息

1999年，欧洲委员会（EC）和欧洲空间局（ESA）开始了“伽利略”系统的定义阶段。按计划“伽利略”系统是在民航控制下的全球卫星导航系统，为全球提供卫星导航和授时服务。早在“伽利略”系统的定义阶段，EC和ESA就已开展了一系列的市场调研和系统定义研究，还进行了硬件和应用软件的预先研发。针对于商业市场、专业领域、生命安全和保险相关的应用领域的需求，“伽利略”将提供遍及全球的开放服务和受控访问服务。定位服务的精度在5m范围内。本文介绍目前正在ESA的伽利略卫星计划框架内研究的“伽利略”空间段和与之相关的地面段的主要设计特色。着重介绍系统结构和性能。与本文配套的有关空间段和地面段活动的专论将分别提交发表。

关键词：全球卫星导航系统欧洲空间局伽利略地面段定位服务应用软件

Coulomb drag between in-plane graphene double ribbons and the impact of the dielectric constant

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Nano Research 2013年第12期6卷 897-905页

作者： Hongyan Chen joerg.Appenzeller Electrical and Computer Engineering Department Purdue University West Lafayette IN 47907 USA

With recent developments in the search for novel device ideas, understanding electron-electron interaction in low dimensional systems is of particular interest. Coulomb drag measurements can provide critical insights in this context. In this article, we present a novel planar graphene double ribbon structure that shows for the first time that Coulomb drag is observable in two adjacent monolayer ribbons in the same plane at room temperature. Moreover, our planar devices enable experimentally study of the impact of the dielectric constant on Coulomb drag which is difficult to explore in the typically used double layer graphene structures. Our experimental findings indicate in particular that the drag resistance is proportional to the dielectric constant （~） and does not, as recently reported, show an increasing trend of interaction strength for small C-values. In fact, we find that the drag resistance follows approximately an ~l.2-dependence. The exponent of ＂1.2＂ is consistent with the theory considering the carrier concentration in our samples, and positions our results in between the weak and strong coupling limits.

关键词： Coulomb drag graphene ribbon dielectric scattering electron-electroninteractions

Sequence diversity of hepatitis C virus: Implications for immune control and therapy

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World Journal of Gastroenterology 2007年第36期13卷 4807-4817页

作者： joerg.Timm Michael Roggendorf University of Essen Instituteof Virology Essen 45122 Germany

With approximately 3% of the world’s population (170 million people) infected with the hepatitis C virus (HCV), the WHO has declared HCV a global health problem. Upon acute infection about 50%-80% of subjects develop chronic hepatitis with viral persistence being at risk to develop liver cirrhosis and hepatocellular carcinoma. One characteristic of HCV is its enormous sequence diversity, which represents a significant hurdle to the development of both effective vaccines as well as to novel therapeutic interventions. Due to a polymerase that lacks a proofreading function HCV presents with a high rate of evolution, which enables rapid adaptation to a new environment including an activated immune system upon acute infection. Similarly, novel drugs designed to specifically inhibit viral proteins will face the potential problem of rapid selection of drug resistance mutations. This review focuses on the sequence diversity of HCV, the driving forces of evolution and the impact on immune control and treatment response. An important feature of any therapeutic or prophylactic intervention will be an efficient attack of a structurally or functionally important region in the viral protein. The understanding of the driving forces, but also the limits of viral evolution, will be fundamental for the design of novel therapies.

关键词： Hepatitis C Virus Evolution Escape Drug resistance Selection

PARALLEL HIERARCHICAL MATRIX PRECONDITIONERS FOR THE CURL-CURL OPERATOR

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Journal of Computational Mathematics 2009年第5期27卷 624-641页

作者： Mario Bebendorf joerg.Ostrowski Institut fur Numerische Simulation Universitat BonnWegelerstrasse 653115 BonnGermany ABB Switzerland Ltd Corporate ResearchSegelhofstrasse 1 K/P.O.BoxCH-5405 Baden 5 Dattwil

This paper deals with the preconditioning of the curl-curl operator. We use H（curl）- conforming finite elements for the discretization of our corresponding magnetostatic model problem. Jumps in the material parameters influence the condition of the problem. We will demonstrate by theoretical estimates and numerical experiments that hierarchical matrices are well suited to construct efficient parallel preconditioners for the fast and robust iterative solution of such problems.

关键词： Computational electromagnetism Preconditioners Hierarchical matrices Parallelization.

Influence of rotating wakes on separation in turbine exhaust diffusers

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Journal of Thermal Science 2008年第1期17卷 42-49页

作者： Olaf Sieker joerg.R.Seume Department of Turbomachinery and Fluid Dynamics Leibniz University HannoverAppelstr.9DE-30167 HannoverGermany Dipl.-Ing. Department of Turbomachinery and Fluid Dynamics Leibniz University HannoverAppelstr.9DE-30167 HannoverGermany

Highly efficient turbine exhaust diffuser cannot be designed without taking into account the unsteady interactions with the last rotating row of the turbine. Former investigations described in the literature show a very high potential compared to that of other parts of turbomachines for improving the diffuser. A scale model of a typical gas turbine exhaust diffuser is investigated experimentally. To investigate the influence of rotating wakes, measurements without a spoke wheel as well as measurements with a variable-speed rotating cylindrical spoke wheel with 2 mm- or 10 mm-spokes simulating turbine rotor wakes were made. Miniaturized 3-hole pneumatic probes as well as a 2D-Laser-Doppler-Velocimeter （LDV） were used to investigate velocity profiles. 122 static pressure tapings were used to measure several axial and circumferential static pressure distributions. Without a spoke-wheel the annular diffuser separates at the shroud for all swirl configurations. For the measurements with the 2 mm spoke wheel, the separating diffuser was unstable while keeping the test rig operating parameters constant. For a non-rotating 10 mm spoke wheel and at rotational speeds less than 1,000 rpm, the annular diffuser separated at the shroud. Increasing the rotational speed of the 10mm spoke wheel, flow did not separate at the shroud and much higher pressure recovery than without spoke wheel has achieved.

关键词： turbine exhaust diffuser rotating wakes separation LDV

Anti-angiogenesis in hepatocellular carcinoma treatment: Current evidence and future perspectives

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World Journal of Gastroenterology 2011年第26期17卷 3075-3081页

作者： Martin-Walter Welker joerg.Trojan Medizinische Klinik 1 Klinikum der Johann Wolfgang Goethe-Universitt

Hepatocellular carcinoma(HCC) is among the most common cancer diseases *** hypervascularisation is an essential step for HCC tumorigenesis and can be targeted by transarterial chemoembolization(TACE).This interventional method is the standard treatment for patients with intermediate stage HCC,but is also applied as "bridging" therapy for patients awaiting liver transplantation in many centers *** the devascularization effect induced by TACE is transient,consequently resulting in repeated cycles of TACE every 4-8 *** documented survival benefits,TACE can also induce the up-regulation of proangiogenic and growth factors,which might contribute to accelerated progression in patients with incomplete *** 2007,sorafenib,a multi-tyrosine kinase and angiogenesis inhibitor,was approved as the first systemic treatment for advanced stage *** active targeted compounds,either inhibitors of angiogenesis and/or growth factors,are currently being investigated in numerous clinical *** overcome revascularisation or tumor progression under TACE treatment it seems therefore attractive to combine TACE with systemic targeted agents,which might theoretically block the effects of proangiogenic and growth *** the last 12 mo,several retrospec-tive or prospective cohort studies combining TACE and sorafenib have been ***,robust results of the efficacy and tolerability of such combination strategies as proven by randomized,controlled trials are awaited in the next two years.

关键词： Hepatocellular carcinoma Sorafenib Anti-angiogenesis Transarterial chemoembolization

SARS-CoV-2 nanobodies 2.0

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Signal Transduction and Targeted Therapy 2021年第6期6卷 1640-1642页

作者： Fabien Labroussaa joerg.Jores Institute of Veterinary Bacteriology Department of Infectious Diseases and PathobiologyUniversity of BernBernSwitzerland

In a recent study published in Science,Koenig et al.1 reported on rationally engineered biparatopic nanobodies targeting the receptor-binding domain(RBD)of the spike protein that not only efficiently neutralize SARS-CoV-2,but additionally suppress mutational *** growth,increased travel and climate change foster epidemic and pandemic threats by(re)emerging viruses.

关键词： al. travel rational

Interaction between Struts and Swirl Flow in Gas Turbine Exhaust Diffusers

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Journal of Thermal Science 2005年第4期14卷 314-320页

作者： Roman Z.PIETRASCH joerg.R.SEUME Turbomachinery Laboratory University of Hannover Appelstr. 9 D-31678 Hannover Germany

The increasing use of gas turbines in combined cycle power plants together with the high amount of kinetic energy in modem gas turbine exhaust flows focuses attention on the design of gas turbine diffusers as the connecting part between the Brayton/Joule and the Rankine parts of the combined cycle. A scale model of a typical gas turbine exhaust diffuser is investigated experimentally. The test rig consists of a radial type, variable swirl generator which provides the exhaust flow corresponding to different gas turbine operating conditions. Static pressure measurements are carried out along the outer diffuser walls and along the hub of the annular part and along the centerline of the conical diffuser. Velocity distributions at several axial positions in the annular and conical diffuser have been measured using a Laser Doppler Velocimeter （LDV）. Pressure recovery coefficients and velocity profiles are depicted as a function of diffuser length for several combinations of swirl strength, tip flow and strut geometries. The diffuser without struts achieved a higher pressure recovery than the diffuser with struts at all swirl angle settings. The diffuser with cylindrical struts achieved a higher pressure recovery than the diffuser with profiled struts at all swirl angle ***. Inlet flows with swirl angles over 18° affected the pressure recovery negatively for all strut configurations.

关键词： gas turbine exhaust diffuser swirl struts pressure recovery coefficient.

Alcohol binging causes peliosis hepatis during azathioprine therapy in Crohn's disease

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World Journal of Gastroenterology 2007年第34期13卷 4646-4648页

作者： Christoph Elsing joerg.Placke Thomas Herrmann Department of Gastroenterology St Elsiabeth Hospital Dorsten Germany Institute of Pathology and Cytology Dinslaken Germany Department of Gastroenterology University of Heidelberg Heidelberg 69120 Germany

Patients with inflammatory bowel disease have normal life expectancy and, due to modern immunosuppressive therapies, also a normal quality of life. Since mostly young people are affected, their social behaviour suits this environment. Alcohol binging is an increasingly disturbing factor among young people. We describe a patient with Crohn's disease, treated with azathioprine, who developed peliosis hepatis after three epsiodes of alcohol binging. Liver toxicity was not observed previously during the course of the treatment. Azathioprine-induced peliosis hepatis is thought to be idiosyncratic in humans. From animal studies, however, it is clear that hepatic depletion of glutathione leads to azathioprine toxicity to the sinusoidal endothelial cells. Damage of these cells causes peliosis hepatis. Since alcohol binging leads to hepatic glutathione depletion, we conclude that in our patient the episodes of binging have reduced liver gluathione content and therefore this has increased azathioprine toxicity causing peliosis hepatis. The problem of alcohol binging has not yet been addressed in IBD patients undertaking immunosuppressive therapy. This should be reviewed in future considerations regarding patients advice.

关键词： Inflammatory bowel disease Treatment Sideeffects Alcohol Liver