6,139 research outputs found

    Proposal for a conceptually new compact collecting optics for powerful light sources

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    Testing of a spacecraft under simulated outer space conditions is the best guarantee for a successful mission, and for almost all of the parameters a good match (to within a few percent) may be reached in relevant test facilities (e.g., IR background, earthshine and albedo radiation, residual atmosphere, intensity stability, distribution and spectrum of the solar radiation). The collimation angle of the sun (32 arc min) is, however, a drastic exception, here only + or - 1.5 to 2 deg are achieved which means a relative deviation by nearly one order of magnitude. The main reason for this is the presently used collecting optics having unnecessary large diameters. Here a lens-mirror combination is proposed which allows the reduction of the diameter by nearly a factor of two and to achieve with the present Xenon arc lamps a collimation angle of + or - 0.8 deg

    A new type of lamp and reflector for I.R. simulation

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    The lamps and reflectors used for infrared radiation simulation tests at ESTEC did not allow researchers to predict the intensity needed for test conditions with the desired accuracy. This was due to poor reproducibility of the polar diagrams, the unknown contribution of the radiation in the long wavelength range in vacuum, imperfections in the quartz bulbs, and misalignment of the lamp in the reflector. When using a 1000 W coiled spiral quartz lamp with a diffuse reflector, these shortcomings are overcome. Due to the good reproducibility, an overall accuracy within plus or minus 2 percent should be obtained

    Effective charge and free energy of DNA inside an ion channel

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    Translocation of a single stranded DNA (ssDNA) through an alpha-hemolysin channel in a lipid membrane driven by applied transmembrane voltage V was extensively studied recently. While the bare charge of the ssDNA piece inside the channel is approximately 12 (in units of electron charge) measurements of different effective charges resulted in values between one and two. We explain these challenging observations by a large self-energy of a charge in the narrow water filled gap between ssDNA and channel walls, related to large difference between dielectric constants of water and lipid, and calculate effective charges of ssDNA. We start from the most fundamental stall charge qsq_s, which determines the force Fs=qsV/LF_s= q_s V/L stalling DNA against the voltage V (L is the length of the channel). We show that the stall charge qsq_s is proportional to the ion current blocked by DNA, which is small due to the self-energy barrier. Large voltage V reduces the capture barrier which DNA molecule should overcome in order to enter the channel by qcV|q_c|V, where qcq_c is the effective capture charge. We expressed it through the stall charge qsq_s. We also relate the stall charge qsq_s to two other effective charges measured for ssDNA with a hairpin in the back end: the charge quq_u responsible for reduction of the barrier for unzipping of the hairpin and the charge qeq_e responsible for DNA escape in the direction of hairpin against the voltage. At small V we explain reduction of the capture barrier with the salt concentration.Comment: Typos are correcte

    Ah ain't heard whut de tex' wuz : the (il)legitimate textuality of Old English and Black English

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    In this essay I examine two texts from radically different cultural situations: Anglo-Saxon monasteries and the rural Black South. Nevertheless, their respective provenance--in terms of speaker, reporter and legitimizing institution--bear intriguing similarities. Each text is concerned with the biography of the oral poet and issues of transcribing his orality.//, quotation marks removed from title to ensure alphabetical order. Difference as follows; "Ah ain't heard whut de tex' wuz": The (Il)legitimate Textuality of Old English and Black Englis

    Siesta

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    https://digitalcommons.library.umaine.edu/mmb-ps/1160/thumbnail.jp

    The Latin Bible as Codex

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    The University of Pennsylvania Libraries A.S.W. Rosenbach Lectures in Bibliography for 2008 The Latin Bible as Codex Paul Saenger, The Newberry Library, Chicago, Illinois April 14, 15, and 17, 2008 5:30PM Rosenwald Gallery, 6th floor Van Pelt-Dietrich Library University of Pennsylvania 3420 Walnut Street Philadelphia PA 19104-6206 Monday, April 14, 2008: Christian Versification Tuesday, April 15, 2008: The Birth of Modern Chapters Thursday, April 17, 2008: The Printed Codex The distinguished scholar of medieval reading practices Paul Saenger presents three lectures on the development of the medieval and early printed Bible. Co-editor of the 1999 The Bible as Book: The First Printed Editions, Dr. Saenger has also published Space Between Words: The Origins of Silent Reading (1997) and the Catalogue of the Pre-1500 Western Manuscript Books at the Newberry Library (1989)

    RECENT DEVELOPMENTS IN EUROPEAN COMPANY AND BUSINESS LAW

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    [Company Law, Business Law and Capital Markets Law in Europe are widely influenced by a multitude of regulations and directives as well as by the case-law of the European Court of Justice. There have already been nu- merous cases in which the ECJ gave fresh impetus to several developments which were slowed down before by specific statutory provisions of individual Member States. The most recent reason for a special focus on the up-to-date developments are the prevailing dynamics in EU-wide harmonization of law in general and in particular the Action Plan on “Modernising Company Law and Enhancing Corporate Governance in the EU” presented by the Euro- pean Commission.]

    Comunicación de Resistencia y Proyectos Políticos.

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    En el marco de la hegemonía de los medios de comunicación y del modelo imperante de orden social, articulado por el sistema capitalista neoliberal, se abre la pregunta sobrelas posibilidades de transformación social y el rol que podrían jugar en ella los medios alternativos de comunicación organizados colectivamente. El presente artículo resume dos etapas de investigación llevadas a cabo entre los años 2013 y 2015, analizando en un primer momento el trabajo de cinco colectivos de comunicación, dos colombianos, uno peruano y dos chilenos, en torno a los ejes de “tiempo”, “espacio” y “tecnología”, identificados por Manuel Castells como característicos de los movimientos sociales quebuscan construir identidades de resistencia al sistema capitalista neoliberal. En la segunda etapa de investigación, se busca conocer algunas características principales de los proyectos de sociedad impulsados por estos y otros casos decomunicación de resistencia, entre ellos colectivos de Argentina y México, explorando las posibilidades de descripción de estos proyectos por fuera de una oposición y describiendo algunas contradicciones en el desarrollo de proyectos de sociedad que surgen dentro de otra. Esto a fin de aproximarnos a dilucidar si estos actores sociales se acercan a lo que Manuel Castells define como Identidad Proyecto

    CO 603 Orientation to Christian Approaches to Diagnosis and Treatment Planning

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    1) Anderson, N.T., Zuehlke, T.E. & Zuehlke, J. (2000). Christ Centered Therapy. Grand Rapids: Zondervan. 2) Johnson, E.L. & Jones, S.L. (eıs.) (2000). Psychology and Christianity: Four Views. Ill: Intervarsity Press.https://place.asburyseminary.edu/syllabi/2305/thumbnail.jp
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