229 research outputs found

    Experience and results of the 1991 MTLRS-1 USSR campaign

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    The year 1991 was a special year for the mobile laser ranging systems. Due to the scheduled upgrades of the Modular Transportable Laser Ranging Systems, MTLRS#1 and MTLRS#2, neither a WEGENER MEDLAS nor a Crustal Dynamics Project campaign was carried out in 1991. After the successful upgrade of MTLRS#1 in the first half of 1991 the system departed from Wettzell in August to make measurements at two sites in the USSR. In Riga/Latvia, we operated close to the fixed SLR system. In Simeiz/Ucrainea, the place for MTLRS#1 pad was choosen to collocate the two fixed SLR stations in Simeiz (300 m distance to MTLRS#1) and Kazivelli (about 3 km distance)

    The Bovine Seminal Plasma Protein PDC-109 Possesses Pan-Antiviral Activity

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    Mammalian seminal plasma contains a multitude of bioactive components, including lipids, glucose, mineral elements, metabolites, proteins, cytokines, and growth factors, with various functions during insemination and fertilization. The seminal plasma protein PDC-109 is one of the major soluble components of the bovine ejaculate and is crucially important for sperm motility, capacitation, and acrosome reaction. A hitherto underappreciated function of seminal plasma is its anti-microbial and antiviral activity, which may limit the sexual transmission of infectious diseases during intercourse. We have recently discovered that PDC-109 inhibits the membrane fusion activity of influenza virus particles and significantly impairs viral infections at micromolar concentrations. Here we investigated whether the antiviral activity of PDC-109 is restricted to Influenza or if other mammalian viruses are similarly affected. We focused on Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), the etiological agent of the Coronavirus Disease 19 (COVID-19), thoroughly assessing PDC-109 inhibition with SARS-CoV-2 Spike (S)-pseudotyped reporter virus particles, but also live-virus infections. Consistent with our previous publications, we found significant virus inhibition, albeit accompanied by substantial cytotoxicity. However, using time-of-addition experiments we discovered a treatment regimen that enables virus suppression without affecting cell viability. We furthermore demonstrated that PDC-109 is also able to impair infections mediated by the VSV glycoprotein (VSVg), thus indicating a broad pan-antiviral activity against multiple virus species and families.Open Access Publication Fund of the University of Duisburg-EssenPeer Reviewe

    H-Diplo Roundtable Review

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    Cambridge:Harvard University Press. 2014. ISBN: 9780674729711 (hardcover, $45.00/£29.95/€35.00) Modern European history was under the anniversary spotlight in 2014-2015. The centenary of the beginning of the First World War brought forth a steady stream of commemorations and publications. Standing out was Christopher Clark’s The Sleepwalkers, a global bestseller, whose controversial reinterpretation of the crisis of July 1914 and of the responsibility for its violent outcome ignited a widespread academic and public debate.1 Overshadowed by the anniversary of the Great War’s outbreak was the bicentenary of another great war’s conclusion, two hundred years after the end of the Napoleonic wars. In this relatively subdued realm, most of the attention was devoted to the final instance of armed conflict, with official commemorations of, books about, large-scale reenactments of, and multimedia exhibitions displaying the Battle of Waterloo

    The new MTLRS transmitting system

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    This paper presents a detailed description about the new transmitting system of the Modular Transportable Laser Ranging Systems MTLRS-1/2. A simplified theory of the Self Filtering Unstable Resonator (SFUR) is explained. Laser design details are discussed concerning the extreme environmental conditions in which these mobile systems are operating. Details are given concerning the new avalanche START detector. The new SFUR laser and START detector are necessary parts in order to bring both mobile systems towards 1 cm ranging accuracy

    Results of the MTLRS-1 upgrade

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    In this report, the results of the upgrade of the German Modular Transportable Laser Ranging System MTLRS-1 are summarized. A short description of the new components and their influence on the system accuracy is given. It is shown, that the single shot accuracy of the MTLRS-1 has been improved from 5 cm to 1 cm

    Transputer based control system for MTLRS

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    The Modular Transportable Laser Ranging Systems (MTLRS-1 and MTLRS-2) have been designed in the early eighties and have been in operation very successfully since 1984. The original design of the electronic control system was based on the philosophy of parallel processing, but these ideas could at that time only be implemented to a very limited extent. This present system utilizes two MOTOROLA 6800 8-bit processors slaved to a HP A-600 micro-computer. These processors support the telescope tracking system and the data-acquisition/formatting, respectively. Nevertheless, the overall design still is largely hardware oriented. Because the system is now some nine years old, aging of components increases the risk of malfunctioning and some components or units are outdated and not available anymore. The control system for MTLRS is now being re-designed completely, based on the original philosophy of parallel processing, making use of contemporary advanced electronics and processor technology. The new design aims at the requirements for Satellite Laser Ranging (SLR) in the nineties, making use of the extensive operational experience obtained with the two transportable systems

    Interferon-β 1a and SARS Coronavirus Replication

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    A global outbreak of severe acute respiratory syndrome (SARS) caused by a novel coronavirus began in March 2003. The rapid emergence of SARS and the substantial illness and death it caused have made it a critical public health issue. Because no effective treatments are available, an intensive effort is under way to identify and test promising antiviral drugs. Here, we report that recombinant human interferon (IFN)-β 1a potently inhibits SARS coronavirus replication in vitro

    Beschäftigungsformen

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    Inhalt: C Beschäftigungsformen; C.I Einführung und Resümee; C.II Entwicklung und Struktur der Beschäftigungsverhältnisse; C.III Teilzeitbeschäftigung; C.IV Zeitarbeit und Befristungen; C.V Beschäftigungsformen im europäischen Vergleich; Literatur zu Kapitel C

    Homophily and Contagion Are Generically Confounded in Observational Social Network Studies

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    We consider processes on social networks that can potentially involve three factors: homophily, or the formation of social ties due to matching individual traits; social contagion, also known as social influence; and the causal effect of an individual's covariates on their behavior or other measurable responses. We show that, generically, all of these are confounded with each other. Distinguishing them from one another requires strong assumptions on the parametrization of the social process or on the adequacy of the covariates used (or both). In particular we demonstrate, with simple examples, that asymmetries in regression coefficients cannot identify causal effects, and that very simple models of imitation (a form of social contagion) can produce substantial correlations between an individual's enduring traits and their choices, even when there is no intrinsic affinity between them. We also suggest some possible constructive responses to these results.Comment: 27 pages, 9 figures. V2: Revised in response to referees. V3: Ditt
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