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Superconvergence of a Galerkin FEM for Higher-Order Elements in Convection-Diffusion Problems

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Numerical Mathematics(Theory,Methods and Applications) 2014年第3期7卷 356-373页

作者： sebastian Franz H.-G.Roos Institut für Numerische Mathematik Technische Universit¨at Dresden01062 DresdenGermany

In this paper we present a first supercloseness analysis for higher-order Galerkin FEM applied to a singularly perturbed convection-diffusion *** a solution decomposition and a special representation of our finite element space,we are able to prove a supercloseness property of p+1/4 in the energy norm where the polynomial order p≥3 is odd.

关键词： Singular perturbation layer-adapted meshes superconvergence postprocessing

Latent HIV-1 TAR Regulates 7SK-responsive P-TEFb Target Genes and Targets Cellular Immune Responses in the Absence of Tat

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Genomics, Proteomics & Bioinformatics 2017年第5期15卷 313-323页

作者： sebastian Eilebrecht Bernd-Joachim Benecke Arndt G. Benecke CNRS UMR8246 Université Pierre et Marie Curie Paris 75005 France ACSIOMA GmbH Technologiezentrum Ruhr Bochum 44799 Germany Center for Innate Immunity and Immune Disease University of Washington School of Medicine Seattle WA 98195 USA

The transactivating response element （TAR） structure of the nascent HIV-1 transcript is critically involved in the recruitment of inactive positive transcription elongation factor b （P-TEFb） to the promoter proximal paused RNA polymerase II. The viral transactivator Tat is responsible for subsequent P-TEFb activation in order to start efficient viral transcription elongation. In the absence of the viral transactivator of transcription （Tat）, e.g., during latency or in early stages of HIV tran- scription, TAR mediates an interaction of P-TEFb with its inhibitor hexamethylene bis-aeetamide- inducible protein 1 （HEXIM1）, keeping P-TEFb in its inactive form. In this study, we address the function of HIV-1 TAR in the absence of Tat by analyzing consequences of HIV-1 TAR overexpres- sion on host cellular gene expression. An RNA chimera consisting of Epstein-Barr virus-expressed RNA 2 （EBER2） and HIV-1 TAR was developed to assure robust overexpression of TAR in HEK293 cells. The overexpression results in differential expression of more than 800 human genes. A significant proportion of these genes is involved in the suppression of cellular immune responses, including a significant set of 7SK-responsive P-TEFb target genes. Our findings identify a novel role for HIV-1 TAR in the absence of Tat, involving the interference with host cellular immune responses by targeting 7SK RNA-mediated gene expression and P-TEFb inactivation.

关键词： HIV-1 Latency TAR 7SK RNA Cellular immunity

Innate immune recognition and modulation in hepatitis D virus infection

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World Journal of Gastroenterology 2020年第21期26卷 2781-2791页

作者： Stephanie Jung sebastian Maximilian Altstetter Ulrike Protzer Institute of Virology Technical University of Munich/Helmholtz Zentrum MünchenMunich D-81675Germany German Center for Infection Research(DZIF) Munich Partner SiteMunich D-81675Germany

Hepatitis D virus(HDV)is a global health threat with more than 15 million humans *** treatment options are largely unsatisfactory leaving chronically infected humans at high risk to develop liver cirrhosis and hepatocellular *** is the only human satellite virus *** encodes only two proteins,and requires Hepatitis B virus(HBV)envelope protein expression for productive virion release and spread of the *** HDV could evolve and why HBV was selected as a helper virus remains *** the discovery of Na+-taurocholate co-transporting polypeptide as the essential uptake receptor for HBV and HDV,we are beginning to understand the interactions of HDV and the immune *** HBV is mostly regarded a stealth virus,that escapes innate immune recognition,HBV-HDV coinfection is characterized by a strong innate immune *** RNA sensor melanoma differentiation antigen 5 has been reported to recognize HDV RNA replication and activate innate *** immunity,however,seems not to impair HDV replication while it inhibits *** this review,we describe what is known up-to-date about the interplay between HBV as a helper and HDV’s immune evasion strategy and identify where additional research is required.

关键词： Hepatitis D virus Hepatitis B virus Innate immunity Pathogen-associated molecular pattern molecules Immune evasion Immunosuppression

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用户体验和装配:以人为本

现代制造 2024年第2期 36-36页

作者： sebastian Human 不详

UX是英文“Positive User Experience良好的用户体验”一词的缩写,指的是企业员工,尤其是装配工使用装配工位器具时的“用户体验”。用户体验不仅提高了装配工的安装工作效率,也提高了装配工的生产能力。但用户体验的UX策略是如何支持... 详细信息

UX是英文“Positive User Experience良好的用户体验”一词的缩写,指的是企业员工,尤其是装配工使用装配工位器具时的“用户体验”。用户体验不仅提高了装配工的安装工作效率,也提高了装配工的生产能力。但用户体验的UX策略是如何支持装配工作流程优化的呢?它与安全有什么关系呢?

关键词：用户体验工位器具工作流程优化工作效率以人为本装配生产能力

Non-invasive diagnosis of alcoholic liver disease

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World Journal of Gastroenterology 2014年第40期20卷 14626-14641页

作者： sebastian Mueller Helmut Karl Seitz Vanessa Rausch Department of Internal Medicine Salem Medical Center University of Heidelberg 69121 Heidelberg Germany Center for Alcohol Research University of Heidelberg 69121 Heidelberg Germany

Alcoholic liver disease(ALD)is the most common liver disease in the Western *** many reasons,it isunderestimated and *** early diagnosis is absolutely essential since it(1)helps to identify patients at genetic risk for ALD;(2)can trigger efficient abstinence namely in non-addicted patients;and(3)initiate screening programs to prevent life-threateningcomplications such as bleeding from varices,spontaneous bacterial peritonitis or hepatocellular *** two major end points of ALD are alcoholic liver cirrhosis and the rare and clinically-defined alcoholic hepatitis(AH).The prediction and early diagnosis of both entities is still insufficiently solved and usually relies on acombination of laboratory,clinical and imaging *** is not widely conceived that conventional screeningtools for ALD such as ultrasound imaging or routine laboratory testing can easily overlook ca.40%of manifest alcoholic liver ***-invasive methods such as transient elastography(Fibroscan),acoustic radiation force impulse imaging or shear wave elastography have significantly improved the early diagnosis of *** algorithms allow either the exclusion or the exact definition of advanced fibrosis stages in ca.95%of *** correct interpretation of liver stiffness requires a timely abdominal ultrasound and actual transaminase *** non-invasive methods such as controlled attenuation parameter,serum levels of M30 or M65,susceptometry or breath tests are under current evaluation to assess the degree of steatosis,apoptosis and iron overload in these *** biopsy still remains an important option to rule out comorbidities and to confirm the prognosis namely for patients with AH.

关键词： Alcoholic hepatitis Alcoholic steatohepatitis Alcoholic liver disease Non-invasive Liver stiffness Serum marker Steatosis

Comparison of EUV Photomask Metrology Between CD-AFM and TEM

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Nanomanufacturing and Metrology 2022年第2期5卷 91-100页

作者： Gaoliang Dai Kai Hahm Lipfert sebastian Markus Heidelmann Physikalisch-Technische Bundesanstalt 38116BraunschweigGermany Advanced Mask Technology Center GmbH&Co.KG 01109DresdenGermany ICAN Universität Duisburg-Essen47057DuisburgGermany

Accurate metrology of extreme ultraviolet (EUV) photomask is a crucial task. In this paper, two different methods for reference EUV photomask metrology are compared. One is the critical dimension atomic force microscopy (CD-AFM). In the measurements, the contribution of its AFM tip geometry is usually the dominant error source, as measured AFM images are the dilated results of measured structures by the AFM tip geometry. To solve this problem, a bottom-up approach has been applied in calibrating the (effective) AFM tip geometry where the result is traceably calibrated to the lattice constant of silicon crystals. The other is transmission electron microscopy (TEM). For achieving measurement traceability, structure features are measured in pairs in TEM images;thus the distance between the structure pair calibrated by a metrological AFM in prior can be applied to determine the magnification of the TEM image. In this study, selected photomask structures are calibrated by the CD-AFM, and then sample prepared and measured by high-resolution TEM nearly at the same location. The results are then compared. Of six feature groups compared, the results agree well within the measurement uncertainty, indicating excellent performance of the developed methodology. This research supports the development of a photomask standard, which is applied as a “reference ruler” with improved low measurement uncertainty in photomask fabs.

关键词： Extreme ultraviolet(EUV)photomask standard Traceable calibration Metrology Critical dimension(CD) Atomic force microscopy(AFM) Transmission electron microscopy(TEM) High precision Low measurement uncertainty

A comparison of approaches in fitting continuum SEDs

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Research in Astronomy and Astrophysics 2013年第4期13卷 420-434页

作者： Yao Liu David Madlener sebastian Wolf Hong-Chi Wang Purple Mountain Observatory and Key Laboratory for Radio Astronomy Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Institut fr Theoretische Physik und Astrophysik Universitt zu Kiel

We present a detailed comparison of two approaches, the use of a precalculated database and simulated annealing （SA）, for fitting the continuum spectral energy distribution （SED） of astrophysical objects whose appearance is dominated by surrounding dust. While pre-calculated databases are commonly used to model SED data, only a few studies to date employed SA due to its unclear accuracy and convergence time for this specific problem. From a methodological point of view, different approaches lead to different fitting quality, demand on computational resources and calculation time. We compare the fitting quality and computational costs of these two approaches for the task of SED fitting to provide a guide to the practitioner to find a compromise between desired accuracy and available resources. To reduce uncertainties inherent to real datasets, we introduce a reference model resembling a typical circumstellar system with 10 free parameters. We derive the SED of the reference model with our code MC3 D at 78 logarithmically distributed wavelengths in the range [0.3 μm, 1.3 mini and use this setup to simulate SEDs for the database and SA. Our result directly demonstrates the applicability of SA in the field of SED modeling, since the algorithm regularly finds better solutions to the optimization problem than a precalculated database. As both methods have advantages and shortcomings, a hybrid approach is preferable. While the database provides an approximate fit and overall probability distributions for all parameters deduced using Bayesian analysis, SA can be used to improve upon the results returned by the model grid.

关键词： methods numerical - radiative transfer - protoplanetary disks

Combination strategies for pharmacologic treatment of nonalcoholic steatohepatitis

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World Journal of Gastroenterology 2022年第35期28卷 5129-5140页

作者： Jaspreet Suri sebastian Borja Joseph K Lim Department of Gastroenterology Norwalk HospitalNorwalkCT 06856United States Department of Internal Medicine Norwalk HospitalNorwalkCT 06850United States Section of Digestive Diseases Yale University School of MedicineNew HavenCT 06520United States

Non-alcoholic steatohepatitis (NASH) is defined as hepatic steatosis, inflammation,and hepatocyte injury with or without fibrosis. It has emerged as thesecond leading indication for liver transplantation with a rising death rate in thenon-transplantable population. While there are many drugs in evaluation,currently no approved therapies are on the market for this condition. Given thisimportance, the Food and Drug Administration has provided formal guidanceregarding drug development for stopping or reversing NASH or NASH associatedfibrosis. The complex pathogenesis of NASH and its bidirectional relationshipwith metabolic syndrome has highlighted multiple drugs of interest thataddress metabolic, inflammatory, and fibrotic factors. A few promising liverspecific targets include farnesoid X receptor agonists and peroxisome proliferatoractivatedreceptor agonists. Previously studied drug classes such as glucagon-likepeptide-1 analogs or sodium/glucose transport protein 2 inhibitors have alsodemonstrated ability to improve hepatic steatosis. Here we discuss currentrationale, scientific work, and preliminary data in combining multiple drugs forthe purposes of a multimodal attack on the pathogenesis of NASH. We highlightmultiple Phase 2 and Phase 3 studies that demonstrate the potential to achieve aresponse rate higher than previously assessed monotherapies for this ***, one of these combination strategies may rise above in its safety andefficacy to become a part of a standardized approach to NASH.

关键词： Non-alcoholic steatohepatitis Fatty liver Combination treatment Drug therapy Pharmacologic treatment Clinical trials

Phosphorylated Salicylic Acid as Flame Retardant in Epoxy Resins and Composites

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Journal of Renewable Materials 2022年第7期10卷 1931-1950页

作者： Lara Greiner Philipp Kukla sebastian Eibl Manfred Döring Bundeswehr Research Institute for Materials Fuels and LubricantsErding85435Germany Fraunhofer Institute for Structural Durability and System Reliability LBF Darmstadt64289Germany Schill+Seilacher GmbH Böblingen71032Germany

A novel,versatile flame retardant substructure based on phosphorylated salicylic acid(SCP)is described and used in the synthesis of new flame retardants for HexFlowRTM6,a high-performance epoxy resin used in resin transfer molding processes as composite *** starting material salicylic acid can be obtained from natural *** as reactive phosphorus chloride is converted with a novolak,a novolak containing 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide(DOPO)substituents or DOPO-hydroquinone to flame retardants with sufficient thermal stability and high char ***,these flame retardants are soluble in the resin as well as react into the epoxy *** determined thermal stability and glass transition temperatures of flame retarded neat resin samples as well as the interlaminar shear strength of corresponding carbon fiber reinforced composite materials showed the applicability of these flame *** resin samples and composites were tested for their flammability by UL94 and/or flame-retardant performance by cone *** tested flame retardants decrease the peak of heat release rate by up to 54%for neat resin samples.A combination of DOPO and SCP in one flame retardant shows synergistic effects in char formation and the mode of action adapts to neat resin or fiber-reinforced samples,so there is efficient flame retardancy in both ***,a tailoring of SCP based flame retardants is ***,these flame retardants efficiently reduce fiber degradation during combustion of carbon fiber-reinforced epoxy resins as observed by scanning electron microscopy and energy dispersive X-ray spectroscopy.

关键词： Epoxy resin composite fiber protection bio-based flame retardant