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Multidimensional thermally-induced transformation of nest-structured complex Au-Fe nanoalloys towards equilibrium

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Nano Research 2022年第1期15卷 581-592页

作者： Jacob Johny Oleg Prymak Marius Kamp Florent Calvo Se-Ho Kim Anna Tymoczko Ayman El-Zoka Christoph Rehbock Ulrich Schurmann Baptiste Gault Lorenz Kienle stephan Barcikowski Technical Chemistry I and Center for Nanointegration Duisburg-Essen(CENIDE) University of Duisburg-EssenEssen 45141Germany Inorganic Chemistry and Center for Nanointegration Duisburg-Essen(CENIDE) University of Duisburg-EssenEssen 45141Germany Institute for Materials Science Synthesis and Real StructureKiel UniversityKiel 24143Germany University Grenoble Alpes CNRSLiPhyGrenoble 38000France Max-Planck-Institut fur Eisenforschurtg GmbH Diisseldorf40237Germany Department of Materials Royal School of MineImperial College LondonLondon SW72AZUK

Bimetallic nanoparticles are often superior candidates for a wide range of technological and biomedical applications owing to their enhanced catalytic,optical,and magnetic properties,which are often better than their monometallic *** of their properties strongly depend on their chemical composition,crystallographic structure,and phase ***,little is known of how their crystal structure,on the nanoscale,transforms over time at elevated temperatures,even though this knowledge is highly relevant in case nanoparticles are used in,e.g.,high-temperature ***-Fe is a promising bimetallic system where the low-cost and magnetic Fe is combined with catalytically active and plasmonic ***,we report on the in s/fi;temporal evolution of the crystalline ordering in Au-Fe nanoparticles,obtained from a modern laser ablation in liquids *** in-depth analysis,complemented by dedicated atomistic simulations,includes a detailed structural characterization by X-ray diffraction and transmission electron microscopy as well as atom probe tomography to reveal elemental distributions down to a single atom *** show that the Au-Fe nanoparticles initially exhibit highly complex internal nested nanostructures with a wide range of compositions,phase distributions,and size-depended *** elevated temperature induces a diffusion-controlled recrystallization and phase merging,resulting in the formation of a single face-centered-cubic ultrastructure in contact with a body-centered cubic phase,which demonstrates the metastability of these *** these unique nanostructures with nested features could be highly attractive from a fundamental viewpoint as they could give further insights into the nanoparticle formation mechanism under non-equilibrium ***,the in situ evaluation of the crystal structure changes upon heating is potentially relevant for high-temperature process utilization of bimetallic na

关键词： nanoparticles in situ atom probe tomography diffusion recrystallization atomistic simulation

Application of the woodchuck animal model for the treatment of hepatitis B virus-induced liver cancer

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World Journal of Gastrointestinal Oncology 2021年第6期13卷 509-535页

作者： Manasa Suresh stephan Menne Department of Microbiology and Immunology Georgetown University Medical CenterWashingtonDC 20057United States

This review describes woodchucks chronically infected with the woodchuck hepatitis virus(WHV)as an animal model for hepatocarcinogenesis and treatment of primary liver cancer or hepatocellular carcinoma(HCC)induced by the hepatitis B virus(HBV).Since laboratory animal models susceptible to HBV infection are limited,woodchucks experimentally infected with WHV,a hepatitis virus closely related to HBV,are increasingly used to enhance our understanding of virus-host interactions,immune response,and liver disease progression.A correlation of severe liver pathogenesis with high-level viral replication and deficient antiviral immunity has been established,which are present during chronic infection after WHV inoculation of neonatal woodchucks for modeling vertical HBV transmission in *** in chronic carrier woodchucks develops 17 to 36 mo after neonatal WHV infection and involves liver tumors that are comparable in size,morphology,and molecular gene signature to those of HBV-infected ***,woodchucks with WHV-induced liver tumors have been used for the improvement of imaging and ablation techniques of human *** addition,drug efficacy studies in woodchucks with chronic WHV infection have revealed that prolonged treatment with nucleos(t)ide analogs,alone or in combination with other compounds,minimizes the risk of liver disease progression to *** recently,woodchucks have been utilized in the delineation of mechanisms involved in innate and adaptive immune responses against WHV during acute,self-limited and chronic *** interventions based on modulating the deficient host antiviral immunity have been explored in woodchucks for inducing functional cure in HBV-infected patients and for reducing or even delaying associated liver disease sequelae,including the onset of ***,woodchucks with chronic WHV infection constitute a well-characterized,fully immunocompetent animal model for HBV-induced liver cancer and for preclinical

关键词： Woodchuck Hepatitis B virus Chronic infection Liver disease Hepatocellular carcinoma Cancer treatment

Geology of Mars after the first 40 years of exploration

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Research in Astronomy and Astrophysics 2010年第7期10卷 621-652页

作者： Angelo Pio Rossi stephan van Gasselt International Space Science Institute CH-3012 Hallerstrasse 6 Bern Switzerland Jacobs University Bremen Department of Earth and Space Sciences Campus Ring 1 28759 Bremen Germany Planetary Sciences and Remote Sensing Institute of Geological Sciences Free University of Berlin Malteserstr. 74-100 12249 Berlin Germany

The knowledge of Martian geology has increased enormously in the last 40 yr. Several missions orbiting or roving Mars have revolutionized our understanding of its evolution and geological features, which in several ways are similar to Earth, but are extremely different in many respects. The impressive dichotomy between the two Martian hemispheres is most likely linked to its impact cratering history, rather than internal dynamics such as on Earth. Mars＇ volcanism has been extensive, very longlived and rather constant in its setting. Water was available in large quantities in the distant past of Mars, when a magnetic field and more vigorous tectonics were active. Exogenic forces have been shaping Martian landscapes and have led to a plethora of landscapes shaped by wind, water and ice. Mars＇ dynamical behavior continues, with its climatic variation affecting climate and geology until very recent times. This paper tries to summarize major highlights in Mars＇ Geology, and points to deeper and more extensive sources of important scientific contributions and future exploration.

关键词： planets and satellites Mars -- Geology -- surface processes -- interior processes

Successful Detection of a Preferred Frame Using Eclipses of Jupiter’s Moon Io

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Journal of Applied Mathematics and Physics 2022年第2期10卷 322-332页

作者： stephan J. G. Gift Department of Electrical and Computer Engineering Faculty of Engineering The University of the West Indies St. Augustine Trinidad and Tobago

In this paper tests by Maxwell and Gift that search for a preferred frame or ether arising from movement through that frame using Jupiter’s moon Io are reviewed and discussed. Unlike the Michelson-Morley second-order experiment which unsuccessfully attempted to detect the orbital motion of the Earth relative to the ether, these tests are both first-order and therefore are unaffected by the second-order effects of length contraction and clock retardation. The test by Maxwell utilizes the delay in the eclipse of Io as the Earth orbits the Sun in an attempt to detect ether drift resulting from the galactic movement of the Sun. This test requires a 6-year duration for its full execution and was never performed because of practical difficulties. The test first presented by Gift can be conducted over a few days and employs the observed variation of the period of Io as the Earth moves toward or away from Jupiter. The result is a positive detection of ether drift arising from the orbital motion of the Earth. The detected ether drift is evidence of a preferred frame which we argue corresponds to the solar system barycentric or sun-centered inertial (SCI) frame.

关键词： Ether Drift Maxwell Roemer Jupiter Io Luminiferous Ether Preferred Frame Sun-Centered Inertial Frame

Auxin-Oxylipin Crosstalk:Relationship of Antagonists

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Journal of Integrative Plant Biology 2011年第6期53卷 429-445页

作者： Maik Hoffmann Mathias Hentrich stephan Pollmann Centro de Biotecnología y Genómica de Plantas(U.P.M.-I.N.I.A.) Parque Científico y Tecnológico de la U.P.M. Campus de Montegancedo Ruhr-Universitt Bochum Lehrstuhl fr PflanzenphysiologieUniversittsstrasse

Phytohormones regulate a wide array of developmental processes throughout the life cycle of plants. Herein, the various plant hormones may interact additively, synergistically, or antagonistically. By their cooperation they create a delicate regulatory network whose net output largely depends on the action of specific phytohormone combinations rather than on the independent activities of separate hormones. While most classical studies of plant hormonal control have focused mainly on the action of single hormones or on the synergistic interaction of hormones in regulating various developmental processes, recent work is beginning to shed light on the crosstalk of nominally antagonistic plant hormones, such as gibberellins and auxins with oxylipins or abscisic acid. In this review, we summarize our current understanding of how two of the first sight antagonistic plant hormones, i.e. auxins and oxylipins, interact in controlling plant responses and development.

关键词： Auxin biosynthesis crosstalk hormone jasmonic acid.

Estimation of food composition of Hodotermes mossambicus （Isoptera： Hodotermitidae） based on observations and stable carbon isotope ratios

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Insect Science 2011年第2期18卷 175-180页

作者： Craig T. Symes stephan Woodborne School of Animal Plant and Environmental Sciences University of the Witwatersrand Wits Natural Resources and the Environment CSIR Pretoria South Africa

The diet of the harvester termite Hodotermes mossambicus was investigated at two sites with distinct dietary components： C4 grasses （δ13 C isotope values, -13.8%0 to -14.0%0） and C3 plants （δ13C isotope values, -25.6%0 to -27.1%0）. By comparing observations of food items carried into the colony by the termites and carbon isotope ratios of whole termites （that determined assimilated carbon）, the relative proportion of the C3 and C4 plant food components of the termite diet was estimated. There was agreement between the observational data and stable carbon isotopic data, with grass representing approximately 93% of the diet ofH. mossambicus at two study sites （urban and rural） on the South African highveld. However, when correcting for mass of food items, that is, C3 and C4, carried by termites, the proportion of grass （C4） in the diet may be underestimated.

关键词： carbon assimilation colony harvester termite Suikerbosrand

Efficient mid-infrared single-photon detection using superconducting NbTiN nanowires with high time resolution in a Gifford-McMahon cryocooler

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Photonics Research 2022年第4期10卷 1063-1070页

作者： Jin Chang Johannes W.N.Los Ronan Gourgues stephan Steinhauer S.N.Dorenbos Silvania F.Pereira HPaul Urbach Val Zwiller Iman Esmaeil Zadeh Optics Research Group ImPhys DepartmentFaculty of Applied SciencesDelft University of TechnologyDelft 2628 CJThe Netherlands Single Quantum B.V. Delft 2628 CJThe Netherlands KTH Royal Institute of Technology Department of Applied PhysicsAlbanova University Centre10691 StockholmSweden

Shortly after their inception, superconducting nanowire single-photon detectors(SNSPDs) became the leading quantum light detection technology. With the capability of detecting single-photons with near-unity efficiency,high time resolution, low dark count rate, and fast recovery time, SNSPDs outperform conventional single-photon detection techniques. However, detecting lower energy single photons(70% system detection efficiency(SDE) at 2 μm and sub-15 ps timing jitter. Furthermore, detectors from the same batch demonstrated unity internal detection efficiency at 3 μm and 80% internal efficiency at 4 μm, paving the road for an efficient mid-infrared single-photon detection technology with unparalleled time resolution and without mK cooling requirements. We also systematically studied the dark count rates(DCRs) of our detectors coupled to different types of mid-infrared optical fibers and blackbody radiation filters. This offers insight into the trade-off between bandwidth and DCRs for mid-infrared SNSPDs. To conclude, this paper significantly extends the working wavelength range for SNSPDs made from polycrystalline NbTiN to 1.5–4 μm, and we expect quantum optics experiments and applications in the mid-infrared range to benefit from this far-reaching technology.

关键词： nanowires technology SNSPD

RTP payload format for H.264/SVC scalable video coding

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 657-667页

作者： WENGER stephan HANNUKSELA Miska M. Nokia Research Center Tampere 33721 Finland

The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team’s work. In its present working draft, the higher level syntax of SVC follows the design principles of H.264/AVC. Self-contained network abstraction layer units (NAL units) form natural entities for packetization. The SVC specification is by no means finalized yet, but nevertheless the work towards an optimized RTP payload format has already started. RFC 3984, the RTP payload specification for H.264/AVC has been taken as a starting point, but it became quickly clear that the scalable features of SVC require adaptation in at least the areas of capability/operation point signaling and documentation of the extended NAL unit header. This paper first gives an overview of the history of scalable video coding, and then reviews the video coding layer (VCL) and NAL of the latest SVC draft specification. Finally, it discusses different aspects of the draft SVC RTP payload format, in- cluding the design criteria, use cases, signaling and payload structure.

关键词： H.264, Advanced video coding (AVC), Scalable video coding (SVC), Scalability, Real-time transport protocol (RTP), Packetization

How 'Sustainable' are Post-disaster Measures? Lessons to Be Learned a Decade After the 2004 Tsunami in the Indian Ocean

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International Journal of Disaster Risk Science 2017年第1期8卷 33-45页

作者： Christiane stephan Celia Norf Alexander Fekete Institute of Rescue Engineering and Civil Protection TH Koln University of Applied Sciences50679 CologneGermany Department of Geography Rheinische Friedrich Wilhelms Universitat Bonn53113 BonnGermany Department of Environmental Sociology and Technology Assessment University of Stuttgart70174 StuttgartGermany

This article addresses the sustainability implications of post-disaster measures in the context of the 2004 Indian Ocean Tsunami by presenting an analysis of the current situations and changes in some of the affected regions. Sustainability implications of measures are captured by investigating the persistence of the social and economic living conditions in relation to post-disaster measures, and the alignment of the measures with basic environmental aspects. Based on major concepts relevant in disaster science and sustainability research, the study explored sustainability aspects of post-disaster measures implemented after the 2004 tsunami, by conducting selected interviews among the participants of the 2015 international seminar ‘‘11 Years after the Indian Ocean Tsunami 2004'' and a broader online survey. Information was sought about(1) the current state of vulnerability of the local population in the regions affected;(2) the main lessons that have been identified to improve project design and management of recovery and vulnerability reduction;and(3) project sustainability implications with respect to the state of today's vulnerability. Based on the analysis of the information on these three priority areas, selected tasks for future disaster risk management are identified, such as more integrative planning and improved coordination with international organizations and local people.

关键词：灾难风险管理恢复可持续性印度洋海啸灾难以后的措施危险