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Frontiers of physics 2014年第5期9卷 652-664页

作者： Ondrej Stranik Jacqueline Jatschka Andrea Csaki wolfgang Fritzsche Leibniz Institute of Photonic Technology Jena 07745 Germany

Metal nanostructures exhibit special optical resonance modes originating fronl tile subwavelengt.h confinement of conductive electrons in the material. These resonance modes represent a strong research focus due to their application potential in optics and sensing application, in this short review recent achievements of our group in this field are highlighted. A wet-chemistry approach synthesis of advanced metallic nanostruetures will be introduced and their exact positioning and manipulation by electric field is shown. Next. the application of these nanostructures for a detection of small molecules will be described in several examples. Also, it will be shown that inetal nanostruetures can be used for sub-wavelength light focusing and for efficient energy coupling into polymer chains.

关键词： plasmonics sensing nanostructures fabrication energy guiding

Channel adaptive rate control for energy optimization

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 82-88页

作者： BLANCH Carolina POLLIN Sofie LAFRUIT Gauthier EBERLE wolfgang Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium Interdisciplinary Institute for BroadBand TechnologyGent-Ledeberg B-9050Belgium Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium Interdisciplinary Institute for BroadBand TechnologyGent-Ledeberg B-9050 Belgium Department of Electrical EngineeringK.U.LeuvenESAT/INSYSBelgium Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium

Low energy consumption is one of the main challenges for wireless video transmission on battery limited devices. The energy invested at the lower layers of the protocol stack involved in data communication, such as link and physical layer, represent an important part of the total energy consumption. This communication energy highly depends on the channel conditions and on the transmission data rate. Traditionally, video coding is unaware of varying channel conditions. In this paper, we propose a cross-layer approach in which the rate control mechanism of the video codec becomes channel-aware and steers the instantaneous output rate according to the channel conditions to reduce the communication energy. Our results show that energy savings of up to30% can be obtained with a reduction of barely 0.1 dB on the average video quality. The impact of feedback delays is shown to be small. In addition, this adaptive mechanism has low complexity, which makes it suitable for real-time applications.

关键词： Rate control, Channel condition, Communication energy

Non-Viral Deoxyribonucleoside Kinases——Diversity and Practical Use

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Journal of Genetics and Genomics 2015年第5期42卷 235-248页

作者： Louise Slot Christiansen Birgitte Munch-Petersen wolfgang Knecht Department of Biology Lund University Department of Science Systems and ModelsRoskilde University Lund Protein Production Platform Lund University

Deoxyribonucleoside kinases （dNKs） phosphorylate deoxyribonucleosides to their corresponding monophosphate compounds, dNks also phosphorylate deoxyribonucleoside analogues that are used in the treatment of cancer or viral infections. The study of the mammalian dNKs has therefore always been of great medical interest. However, during the last 20 years, research on dNKs has gone into non- mammalian organisms. In this review, we focus on non-viral dNKs, in particular their diversity and their practical applications. The diversity of this enzyme family in different organisms has proven to be valuable in studying the evolution of enzymes. Some of these newly discovered enzymes have been useful in numerous practical applications in medicine and biotechnology, and have contributed to our understanding of the structural basis of nucleoside and nucleoside analogue activation.

关键词： Nucleosides Nucleotides Nucleoside salvage pathway Evolution Suicide gene therapy Deoxynucleosides Deoxynucleotides Deoxy-nucleoside kinases

High resolution, binder-free investigation of the intrinsic activity of immobilized NiFe LDH nanoparticles on etched carbon nanoelectrodes

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Nano Research 2018年第11期11卷 6034-6044页

作者： Patrick Wilde Stefan Barwe Corina Andronescu wolfgang Schuhmann Edgar Ventosa Analytical Chemistry - Center for Electroche.mical Sciences (CES) Ruhr-Universitat Bochum Universitasstr. 150 D-44780 Bochum Germany IMDEA Energy Avda. Ramo de la Sagra 3 28935 Motoles Spain

The determination of the intrinsic properties of nanomaterials is essential for their optimization as electrocatalysts, however it poses great challenges from the standpoint of analytical tools and methods. Herein, we report a novel methodology that allows for a binder-free investigation of electrocatalyst nanoparticles. The potential-assisted immobilization of a non-noble metal catalyst, i.e., nickel-iron layered double hydroxide (NiFe LDH) nanoparticles, was employed to directly attach small nanoparticle ensembles from a suspension to the surface of etched carbon nanoelectrodes. The dimensions of this type of electrodes allowed for the immobilization of the catalyst material below the picogram scale and resulted in a high resolution towards the faradaic current response. In addition the effect of the electrochemical aging on the intrinsic activity of the catalyst was investigated in alkaline media by means of continuous cyclic voltammetry. A change in the material properties could be observed, which was accompanied by a substantial decrease in its intrinsic activity.

关键词： oxygen evolution reaction nickel-iron layered double hydroxide (NiFe LDH) immobilization nanoelectrocatalysis nanoelectrodes nanoimpacts

Particle-Image Velocimetry and Force Measurements of Leading-Edge Serrations on Owl-Based Wing Models

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Journal of Bionic Engineering 2014年第3期11卷 423-438页

作者： Andrea Winzen Benedikt Roidl Stephan Klan Michael Klaas wolfgang Schroder Institute of Aerodynamics RWTH Aachen University Aachen Germany

High-resolution Particle-Image Velocimetry （PIV） and time-resolved force measurements were performed to analyze the impact of the comb-like structure on the leading edge of barn owl wings on the flow field and overall aerodynamic performance. The Reynolds number was varied in the range of 40,000 to 120,000 and the range of angle of attack was 0° to 6° for the PIV and -15° to ＋20° for the force measurements to cover the full flight envelope of the owl. As a reference, a wind-tunnel model which possessed a geometry based on the shape of a typical barn owl wing without any owl-specific adaptations was built, and measurements were performed in the aforementioned Reynolds number and angle of attack： range. This clean wing model shows a separation bubble in the distal part of the wing at higher angles of attack. Two types of comb-like structures, i.e., artificial serrations, were manufactured to model the owl＇s leading edge with respect to its length, thickness, and material properties. The artificial structures were able to reduce the size of the separation region and additionally cause a more uniform size of the vortical structures shed by the separation bubble within the Reynolds number range investigated, resulting in stable gliding flight independent of the flight velocity. However, due to increased drag coefficients in conjunction with similar lift coefficients, the overall aerodynamic performance, i.e., lift-to-drag ratio is reduced for the serrated models. Nevertheless, especially at lower Reynolds numbers the stabilizing effect of the uniform vortex size outperforms the lower aerodynamic performance.

关键词： leading-edge serrations particle-image velocimetry owl-based wing models

Interpreting Morphologically Homogeneous(Paleo-)Populations as Ecological Species Enables Comparison of Living and Fossil Organism Groups,Exemplified by Nummulitid Foraminifera

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Journal of Earth Science 2022年第6期33卷 1362-1377页

作者： Johann Hohenegger Ana Ivis Torres-Silva wolfgang Eder Institute for Paleontology University of Vienna1090ViennaAustria

Morphologically homogeneous groups,either living populations or fossil paleo-populations,must be regarded as ecological species,independent of their molecular genetic resemblance in living *** is always expressed during development by structure genes initiated from a network of regulator genes acting at different times and intensities,additionally being subjected to epigenetic ***,homogeneous populations influenced by the environment represent species better than the reproduction(biological species)or molecular-genetic approach using ancestral sequences like *** and fossil representatives of nummulitid foraminifera were chosen to demonstrate complete reconstruction of morphology using metrical growth-invariant and growth-independent *** these characters,6 models were established to define ecological species in living and fossil ***,a distinction between evolutionary and environmental effects in fossil forms was possible using discriminant analysis showing characters that are responsible for differentiating between evolutionary and environmental trends.

关键词： ecological species growth-invariant metrical characters morphology homogeneity nummulitids

Overlap of concurrent extrahepatic autoimmune diseases is associated with milder disease severity of newly diagnosed autoimmune hepatitis

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Hepatobiliary & Pancreatic Diseases International 2021年第1期20卷 21-27页

作者： Tobias Mühling Helmut Rohrbach wolfgang Schepp Felix Gundling Department of Gastroenterology Internal Medicine ⅡUniversity of WürzburgWürzburgGermany Department of Pathology Academic Teaching Hospital BogenhausenTechnical University of MunichMunich 81925Germany Department of Gastroenterology Hepatology and Gastrointestinal OncologyAcademic Teaching Hospital BogenhausenTechnical University of MunichMunich 81925Germany Department of Internal Medicine Division of GastroenterologyGastrointestinal Oncology and DiabetologyKemperhof KoblenzKoblenzGermany

Background:Concurrent extrahepatic autoimmune disorders(CEHAID)are frequently observed in autoimmune hepatitis(AIH).It is not clear whether there is any prognostic significance of CEHAID on *** aim of this study was to examine the prognostic impact of CEHAID and the correlation with the disease severity of ***:This study included 65 hospitalized subjects who fulfilled the accepted criteria for AIH during an 8-year period(2009–2016).All records were manually screened for presence of associated autoimmune *** severity of AIH was assessed by liver laboratory tests including the ratio of aspartate aminotransferase to alanine aminotransferase(AST/ALT)and liver ***:Among the enrolled patients,52(80%)were female(median age 61 years,IQR 45–75).Fifty-six(86.2%)were classified as type-1 *** 26(40%)patients at least one additional extrahepatic autoimmune disease was ***-four subjects were referred to our hospital because of acute presentation of AIH(supposed by an acute elevation of hepatic enzymes)for subsequent liver biopsy resulting in initial diagnosis of *** group was stratified into 3 subgroups:(A)AIH alone(n=14);(B)overlap with primary biliary cirrhosis(PBC)/primary sclerosing cholangitis(PSC)(n=11);and(C)with CEHAID(n=9).AST/ALT ratio was the lowest in subgroup C(median 0.64,IQR 0.51–0.94;P=0.023),compared to subgroup A(median 0.91,IQR 0.66–1.10)and subgroup B(median 1.10,IQR 0.89–1.36).Patients with AIH alone showed a trend to the highest grade of fibrosis(mean 2.3;95%CI:1.5–3.0)with no statistical significance compared to subjects with CEHAID(lowest grade of fibrosis;mean 1.5;95%CI:0.2–2.8;P=0.380)whereas the ongoing inflammation was ***:AST/ALT ratio and extent of fibrosis were lower in subjects with AIH and CEHAID,compared to subjects with only ***,the occurrence of CEHAID might be a predictor for lower disease severity of newly diagnosed acute onset AIH,possibly caused by an e

关键词： Autoimmune hepatitis Concurrent extrahepatic autoimmune disease Serum aminotransferase activities

Formulation of carbon black-ionomer dispersions for thin film formation in fuel cells

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Particuology 2019年第3期17卷 7-21页

作者： Eva Hoffmann Su Zhang Martin Thoma Cornelia Damm wolfgang Peukert Institute of Particle Technology (LFG) Friedrich-Alexander-Universitat Erlangen-Niimberg (FAU) CauerstraJSe 4 D-91058 Erlangen Germany

The performance of proton exchange membrane fuel cells (PEMFC) is strongly determined by the structure and composition of the electrode *** interactions between the ionomer,carbon black particles,and solvent affect the suspension properties and thus the layer *** analyze the effect of the ionomer-to-carbon (I/C) weight ratio for two different types of carbon black on the suspension and layer *** branched carbon blacks with a high surface area tend to form less cracked *** less branched carbons can pack together more closely,a smaller pore size results in a larger capillary pressure during drying and thus more *** added ionomer adsorbs on the carbon particles and improves the colloidal stability of the carbon black *** carbon black aggregates are thus smaller,resulting in closer packing and thinner ***,the addition of the ionomer increases the critical coating thickness (CCT) of the layers because drying stresses are dissipated by the deformation of the ionomer,preventing crack *** optimum I/C weight ratio is identified for optimal layer formation and minimized crack formation.

关键词： Perfluorosulfonic acid (PFSA) ionomer Carbon black Layer formation Cracking Porosity

Early warning and disaster management:the importance of geographic information(Part B)

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International Journal of Digital Earth 2010年第3期3卷 313-315页

作者： Guest Editors Milan Konecny wolfgang Reinhardt Laboratory on Geoinformatics and Cartography Institute of Geography Faculty of Science Masaryk UniversityKotlarska 261137 BRNOCzech Republic AGIS Geoinformatics Lab Institute of Applied Computer Science(INF4)University of the BundeswehrMu¨nchenGermany

This special issue is part of a double special issue(Part A was published in the previous issue of this journal)dealing with the role of Geographic Information(GI)for Early Warning(EW)and Disaster Management(DM).In the editorial of Part A we gave an introduction to the topic focussing on initiatives from the EU and China and we have highlighted the importance of Digital Earth for EWand *** have also reflected on the outcome of some events organized by the guest editors which were important for the topic and for this special issue.

关键词： journal disaster Early

类雇员——法制史、法教义学及法政治学上的思考

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法治现代化研究 2024年第1期8卷 179-191页

作者： [德]沃尔夫冈·赫罗马德卡李比特(译) 不详南京师范大学法学院中国法治现代化研究院

在发表《雇员概念及劳动法》(NZA 1997,569)这一基础理论性文章后,笔者又撰文对类雇员制度进行进一步探讨。从“类雇员”法律历史渊源到法教义学基础的长期发展最终形成该术语的定义。最后,笔者以相关法政治学上的思考作为结尾为本文画... 详细信息

在发表《雇员概念及劳动法》(NZA 1997,569)这一基础理论性文章后,笔者又撰文对类雇员制度进行进一步探讨。从“类雇员”法律历史渊源到法教义学基础的长期发展最终形成该术语的定义。最后,笔者以相关法政治学上的思考作为结尾为本文画上句号。

关键词：法教义学法制史法政治学理论性文章类雇员劳动法历史渊源