检索结果-南通市图书馆

Streaming and congestion control using scalable video coding based on H.264/AVC

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 749-754页

作者： NGUYEN Dieu Thanh OSTERMANN joern Institute of Information Technology University of Hannover Hannover 30167 Germany

This paper presents a streaming system using scalable video coding based on H.264/AVC. The system provides a congestion control algorithm supported by channel bandwidth estimation of the client. It uses retransmission only for packets of the base layer to disburden the congested network. The bandwidth estimation allows for adjusting the transmission rate quickly to the current available bandwidth of the network. Compared to binomial congestion control, the proposed system allows for shorter start-up times and data rate adaptation. The paper describes the components of this streaming system and the results of experiments showing that the proposed approach works effectively for streaming video.

关键词： Scalable video coding, Congestion control, Bandwidth estimation, Transport protocols, Retransmission

The metabolome identity:basis for discovery of biomarkers in neurodegeneration

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2019年第3期14卷 387-390页

作者： Julie-Myrtille Bourgognon joern R.Steinert MRC Toxicology Unit University of Leicester

Neurodegenerative disorders are often associated with cellular dysfunction caused by underlying protein-misfolding signalling. Numerous neuropathologies are diagnosed at late stage symptomatic changes which occur in response to these molecular malfunctions and treatment is often too late or restricted only to the slowing of further cell death. Important new strategies to identify early biomarkers with predictive value to intervene with disease progression at stages where cell dysfunction has not progressed irreversibly is of paramount importance. Thus, the identification of these markers presents an essential opportunity to identify and target disease pathways. This review highlights some important metabolic alterations detected in neurodegeneration caused by misfolded prion protein and discusses common toxicity pathways identified across different neurodegenerative diseases. Thus, having established some commonalities between various degenerative conditions, detectable metabolic changes may be of extreme value as an early diagnostic biomarker in disease.

关键词： metabolome neurodegeneration neuroinflammation nitric oxide redox stress biomarker misfolded protein prion disease

Grasshoppers （Orthoptera： Acrididae） select vegetation patches in local-scale responses to foliar nitrogen but not phosphorus in native grassland

在线全文

学校读者我要写书评

暂无评论

Insect Science 2011年第5期18卷 533-540页

作者： Viviana Loaiza Jayne L. Jonas Anthony joern Division of Biology Kansas State University Manhattan Kansas USA

Key elements such as nitrogen （N） and phosphorus （P） are often limiting relative to the nutritional needs of herbivores that feed on them. While N often limits insect herbivores in natural terrestrial ecosystems, the effect of P is poorly studied in the field, even though compelling hypotheses from the ecological stoichiometry literature predict its importance. We evaluated small-scale spatial distributions of, and herbivory by, grasshoppers among neighboring plots that vary in foliar-N and -P in tallgrass prairie. Grasshopper densities were 67% greater in N-fertilized plots but detected no effect to grasshopper densities from P-fertilizer. Leaf damage to the dominant grass Andropogon gerardii was 32% greater in N-fertilized plots, but no response to foliar-P was detected. Herbivore damage to a common forb, goldenrod （Solidago missouriensis）, was not strongly linked by fertilizer treatments, although there was increased leaf damage in N-fertilizer treatments when no P was applied （a significant N ~ P interaction）. Under field conditions at local scales, we conclude that spatially heterogeneous distributions of grasshoppers are primarily affected by foliar-N in host plants with little evidence that P-levels contribute to the spatial patterns.

关键词： Andropogon gerardii ecological stoichiometry insect herbivory Konza Prairie N-P fertilization experiment Solidago rnissouriensis

Climate change in the North- past, present and future

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Episodes 2008年第1期31卷 163-167页

作者： joern Thiede Ola M. Johannessen Alfred-Wegner-Institute for Polar and Marine Research in the Helmholtz-Association Am Handelshafen 12 D-27570 Bremerhaven Germany. Nansen Environmental and Remote Sensing Centre （NERSC） Geophysical Institute University of Bergen Thormoehlensgate 47 N-5006 Bergen Norway.

The Nordic countries have produced famous polar explorers and researchers who have generated climate research schools at a variety of locations. The dependence of these countries with respect to the lifelihood of their societies, of their use of lands and seas, the exploitation of marine living and non-living resources have made climate research an eminent topic, and many outstanding discoveries of long- and short-term climate change have been made for the first time in Scandinavia. These include early contributions to our understanding of the geological effects of continent-wide glaciations during the ice ages, the complex postglacial history of the Baltic Sea and the varved sediment sequences preserved from lakes with an extraordinary seasonality in their sediment input, as well as the detailed records of temperature, ice texture and impurities and greenhouse gas variations of the last Glacial and of the Holocene preserved in the ice cores from Greenland. Iceland with its volcanic sequences and intercalated sediment layers not only preserved the history of this subaerial segment of the mid-Atlantic Ridge, but also easily datable paleo-climate records. The fate of the Vikings, who settled during the Medieval climate optimum on Iceland and later on Greenland and who lost their habitat on Greenland at the beginning of the Little Ice Age, illustrates vividly the climate-dependent subsistence of the indigenous and non-indigenous Scandinavian populations. Modern Scandinavian climate research. institutions also include sophisticated modelling groups.

关键词：气候变化北方地区生存条件地质特征

Influence of High-Speed Milling Process on Mechanical and Microstructural Properties of Ultrafine Grained Profiles Produced by Linear Flow Splitting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nanjing University of Aeronautics and Astronautics 2017年第4期34卷 349-356页

作者： Abele Eberhard Müller Clemens Turan Emrah Niehuesbernd joern Bruder Enrico Falk Florian Institute of Production Management Technology and Machine Tools(PTW)Technische Universitt Darmstadt Physical Metallurgy(PhM) Technische Universitt Darmstadt

The effects of milling parameters on the surface quality,microstructures and mechanical properties of machined parts with ultrafine grained(UFG)gradient microstructures are *** effects of the cutting speed,feed per tooth,cutting tool geometry and cooling strategy are *** has been found that the surface quality of machined grooves can be improved by increasing the cutting ***,cryogenic cooling with CO_2 exhibits no significant improvement of surface *** and hardness investigations revealed similar microstructure and hardness variations near the machined groove walls for both utilized tool ***,cryogenic cooling can decrease more far-ranging hardness reductions due to high process temperatures,especially in the UFG regions of the machined parts,whilst it cannot prevent the drop in hardness directly at the groove walls.

关键词： high-speed milling ultrafine grained microstructure linear flow splitting hardness

Socioecological drivers facilitating biodiversity conservation in traditional farming landscapes

在线全文

学校读者我要写书评

暂无评论

Ecosystem Health and Sustainability 2015年第9期1卷 8-17页

作者： Ine Dorresteijn Jacqueline Loos Jan Hanspach joern Fischer Faculty of Sustainability Leuphana University LuneburgScharnhorststraße 121335 LuneburgGermany

Traditional farming landscapes have evolved as tightly coupled socioecological systems that support high ***,land-use change severely threatens the high biodiversity of these *** nature conservation in such landscapes requires a thorough understanding of the key drivers underpinning *** empirical research on mammals,birds,butterflies,and plants in a traditional cultural landscape in Romania,we revealed seven hypothesized drivers facilitating biodiversity *** proportions of three main land-use types support the landscape species pool,most likely through habitat connectivity and frequent spillover between land-use *** complementation and supplementation provide additional habitat for species outside their core *** of woody vegetation cover and gradients in land-cover heterogeneity provide mosaic landscapes with wide ranges of *** land-use practices underpin landscape heterogeneity,traditional land-use elements such as wood pastures,and human-carnivore ***-down predator control may limit herbivore ***,cultural ties between humans and nature have a central influence on people’s values and sustainable use of natural *** approaches should aim to maintain or restore these socioecological drivers by targeting the heterogeneous character of the forest-farmland mosaic at large scales through"broad and shallow"conservation *** large-scale measures should be complemented with"deep and narrow"conservation measures addressing specific land-use types,threats,or *** both cases,conservation measures should integrate the entire socioecological system,by recognizing and strengthening important links between people and the environment.

关键词： countryside biogeography coupled human and natural systems cultural landscapes human–environment systems landscape ecology resilience Romania Special Feature:Ecosystem Management in Transition in Central and Eastern Europe Transylvania

The microbiota is dispensable for the early stages of peripheral regulatory T cell induction within mesenteric lymph nodes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2021年第5期18卷 1211-1221页

作者： Carolin Wiechers Mangge Zou Eric Galvez Michael Beckstette Maria Ebel Till Strowig Jochen Huehn joern Pezoldt Department Experimental Immunology Helmholtz Centre for Infection ResearchBraunschweigGermany Department Microbial Immune Regulation Helmholtz Centre for Infection ResearchBraunschweigGermany Department of Computational Biology for Individualised Medicine Centre for Individualised Infection MedicineHelmholtz Centre for Infection Research and Hannover Medical SchoolHannoverGermany Cluster of Excellence RESIST(EXC 2155) Hannover Medical SchoolHannoverGermany Laboratory of Systems Biology and Genetics École Polytechnique Fédérale de LausanneLausanneSwitzerland

Intestinal Foxp3+regulatory T cell(Treg)subsets are crucial players in tolerance to microbiota-derived and food-borne antigens,and compelling evidence suggests that the intestinal microbiota modulates their generation,functional specialization,and *** bacterial species and microbiota-derived metabolites,such as short-chain fatty acids(SCFAs),have been reported to promote Treg homeostasis in the intestinal lamina ***,gut-draining mesenteric lymph nodes(mLNs)are particularly efficient sites for the generation of peripherally induced Tregs(pTregs).Despite this knowledge,the direct role of the microbiota and their metabolites in the early stages of pTreg induction within mLNs is not fully ***,using an adoptive transfer-based pTreg induction system,we demonstrate that neither transfer of a dysbiotic microbiota nor dietary SCFA supplementation modulated the pTreg induction capacity of *** mice housed under germ-free(GF)conditions displayed equivalent pTreg induction within *** molecular characterization of these de novo induced pTregs from mLNs by dissection of their transcriptomes and accessible chromatin regions revealed that the microbiota indeed has a limited impact and does not contribute to the initialization of the Treg-specific epigenetic ***,our data suggest that the microbiota is dispensable for the early stages of pTreg induction within mLNs.

关键词： Peripheral regulatory T cells Microbiota Tolerance

Observatory science with eXTP

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2019年第2期62卷 97-138页

作者： Jean J.M.in 't Zand Enrico Bozzo JinLu Qu Xiang-Dong Li Lorenzo Amati Yang Chen Immacolata Donnarumma Victor Doroshenko Stephen A.Drake Margarita Hernanz Peter A.Jenke Thomas J.Maccarone Simin Mahmoodifar Domitilla de Martino Alessandra De Rosa Elena M.Rossi Antonia Rowlinson Gloria Sala Giulia Stratta Thomas M.Tauris joern wilms XueFeng Wu Ping Zhou Iván Agudo Diego Altamirano Jean-Luc Atteia Nils A.andersson M.Cristina Baglio David R.Ballantyne Altan Baykal Ehud Behar Tomaso Belloni Sudip Bhattacharyya Stefano Bianchi Anna Bilous Pere Blay Joao Braga Sφren Brandt Edward F.Brown Niccolo Bucciantini Luciano Burderi Edward M.Cackett Riccardo Campana Sergio Campana Piergiorgio Casella Yuri Cavecchi Frank Chambers Liang Chen Yu-Peng Chen Jér?me Chenevez Maria Chernyakova ChiChuan Jin Riccardo Ciolfi Elisa Costantini Andrew Cumming Antonino D'Aì Zi-Gao Dai Filippo D'Ammando Massimiliano De Pasquale Nathalie Degenaar Melania Del Santo Valerio D'Elia Tiziana Di Salvo Gerry Doyle Maurizio Falanga XiLong Fan Robert D.Ferdman Marco Feroci Federico Fraschetti Duncan K.Galloway Angelo F.Gambino Poshak Gandhi MingYu Ge Bruce Gendre Ramandeep Gill Diego G?tz Christian Gouiffès Paola Grandi Jonathan Granot Manuel Güdel Alexander Heger Craig O.Heinke Jeroen Homan Rosario Iaria Kazushi Iwasawa Luca Izzo Long Ji Peter G.Jonker Jordi José Jelle S.Kaastra Emrah Kalemci Oleg Kargaltsev Nobuyuki Kawai Laurens Keek Stefanie Komossa Ingo Kreykenbohm Lucien Kuiper Devaky Kunneriath Gang Li En-Wei Liang Manuel Linares Francesco Longo FangJun Lu Alexander A.Lutovinov Denys Malyshev Julien Malzac Antonios Manousakis Ian McHardy Missagh Mehdipour YunPeng Men Mariano Méndez Roberto P.Mignani Romana Mikusincova M.Coleman Miller Giovanni Miniutti Christian Motch Joonas Nättilä Emanuele Nardini Torsten Neubert Paul T.O'Brien Mauro Orlandini Julian P.Osborne Luigi Pacciani Stéphane Paltani Maurizio Paolillo Iossif E.Papadakis Biswajit Paul Alberto Pellizzoni Uria Peretz Miguel A.Pérez Torres Emanuele Perinati Chanda Prescod-Weinstein Pablo Reig SRON Netherlands Institute for Space Research Department of Astronomy University of Geneva Key Laboratory for Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences School of Astronomy and Space Science Nanjing University INAF-IASF Bologna ASI Via del Politecnico snc INAF-Istituto di Astrofisica e Planetologie Spaziali Institut für Astronomie und Astrophysik Tübingen Universit?t Tübingen NASA Goddard Space Flight Center ICREA&Institute of Space Sciences(IEEC-CSIC) Campus UABCarrer de Can Magrans CSPAR SPA University of Alabama in Huntsville Department of Physics Texas Tech University INAF Osservatorio Astronomico di Capodimonte Leiden Observatory Leiden University Anton Pannekoek Institute University of Amsterdam ASTRON Netherlands Institute for Radio Astronomy Universitat Politecnica de Catalunya(UPC-IEEC) Universitádegli Studi di Urbino‘Carlo Bo’ Max-Planck-Institut für Radioastronomie Dr.Karl-Remeis-Sternwarte and Erlangen Centre for Astroparticle Physics(ECAP) Friedrich Alexander Universit?t Erlangen-Nurnberg Purple Mountain Observatory Chinese Academy of Sciences Instituto de Astrofysíca de Andalucia-CSIC Department of Physics and Astronomy University of Southampton IRAP Universitéde ToulouseCNRSUPSCNES Mathematical Sciences and STAG Research Centre University of Southampton New York University Abu Dhabi Center for Relativistic Astrophysics School of PhysicsGeorgia Institute of Technology Physics Department Middle East Technical University Department of Physics Technion-Israel Institute of Technology INAF Osservatorio Astronomico di Brera Tata Institute of Fundamental Research Dipartimento di Matematica e Fisica Universitàdegli Studi Roma Tre Instituto de Astrofísica de Canarias Instituto Nacional de Pesquisas Espaciais-INPE National Space Institute Technical University of Denmark(DTU Space) Department of Physics and Astronomy Michigan State University INAF Osservatorio Astrofisico di Arcetri Dipartimento di Fisica Universitádegli Studi di Cagliari Department of Physics and A

In this White Paper we present the potential of the enhanced X-ray Timing and Polarimetry(eXTP) mission for studies related to Observatory Science targets. These include flaring stars, supernova remnants, accreting white dwarfs, low and high mass X-ray binaries, radio quiet and radio loud active galactic nuclei, tidal disruption events, and gamma-ray bursts. eXTP will be excellently suited to study one common aspect of these objects: their often transient nature. Developed by an international Consortium led by the Institute of High Energy Physics of the Chinese Academy of Science, the eXTP mission is expected to be launched in the mid 2020s.

关键词： space research in struments nuclear astrophysics flare stars accretion and accretion disks mass loss and stellar winds cataclysmic binaries X-ray binaries supernova remnants active galactic nuclei X-ray bursts gamma-ray bursts gravitational waves

Experimental Study of Energy Consumption Variation in Recurring Driving Trips

在线全文

学校读者我要写书评

暂无评论

Journal of Electrical Engineering 2017年第5期5卷 253-261页

作者： joern Adermann Julian Kreibich Markus Lienkamp Institute of Automotive Tech. Technical University of Munich Garching 85748 Germany