54,481 research outputs found

    Spin Matrix for the Scaled Periodic Ising Model

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    The matrix elements of the spin operator for the periodic Ising model in a basis of eigenvectors for the transfer matrix are calculated in the massive scaling limit

    Liquid-metal-piston MHD generator

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    Magnetohydrodynamic generator uses a slug or piston of liquid potassium as the working fluid. An expanding vapor of the metal is allowed to reciprocate the liquid-metal-piston through a magnetic field and the expansion energy is converted directly into electrical energy

    Experimental demonstration of a Rydberg-atom beam splitter

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    Inhomogeneous electric fields generated above two-dimensional electrode structures have been used to transversely split beams of helium Rydberg atoms into pairs of spatially separated components. The atomic beams had initial longitudinal speeds of between 1700 and 2000 m/s and were prepared in Rydberg states with principle quantum number n=52n=52 and electric dipole moments of up to 8700 D by resonance-enhanced two-color two-photon laser excitation from the metastable 1s2s 3^3S1_1 level. Upon exiting the beam splitter the ensembles of Rydberg atoms were separated by up to 15.6 mm and were detected by pulsed electric field ionization. Effects of amplitude modulation of the electric fields of the beam splitter were shown to cause particle losses through transitions into unconfined Rydberg-Stark states.Comment: 6 pages, 5 figure

    Antenna Technology for QUASAT application

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    A hybrid growth version of the advanced Sunflower, or precision deployable, antenna was adopted as the configuration proposed for the QUASAT very long baseline interferometry mission. The antenna consists of rigid panels of graphite-epoxy facesheets covering aluminum honeycomb sandwich. The six main folding panels are hinged to a cantilevered support ring attached to the periphery of the center section. Six pairs of intermediate panels are located between these panels and are hinged to each other and to the main panels. The flight configuration, antenna weight, a mass properties, frequency, and contour tolerance are discussed. The advantages of the solid antenna surface cover an all-mesh contour are examined

    Apparatus for testing a pressure responsive instrument Patent

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    Control system for pressure balance device used in calibrating pressure gage

    2.9 Incorporation of Inorganic Carbon by Antarctic Cryptoendolithic Fungi

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    High Energy Colliders

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    We consider the high energy advantages, disadvantages and luminosity requirements of hadrons, leptons and photon-photon colliders. Technical problems in obtaining increased energy in each type of machine are presented. The machines relative size are also discussed.Comment: LaTeX, 27 pages, 8 figures (eps, ps). Submitted to the Proceedings of the Princeton's 250th Anniversary Conference on Critical Problems in Physic

    Regulation of anti-inflammatory gene expression in vascular endothelial cells by EPAC1

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    Suppressor of cytokine signalling 3 (SOCS3) is a potent inhibitor of pro-inflammatory pathways involved in atherogenesis and the development of neo-intimal hyperplasia (NIH), which contributes to the in-stent re-stenosis responsible for the failure of percutaneous coronary intervention (PCI) procedures. We have shown that cyclic AMP sensor EPAC1 triggers induction of the SOCS3 gene in vascular endothelial cells (VECs), thereby attenuating interleukin 6 (IL-6)-mediated pro-inflammatory signalling. We propose that EPAC1 localisation to the nuclear pore controls cyclic AMP-mediated activation of a C/EBPβ/c-Jun transcriptional complex, leading to SOCS3 induction and suppression of pro-inflammatory signalling. Future work in this area will involve an integrated approach to determine the wider significance of the EPAC1-C/EBPβ/c-Jun pathway in controlling human VEC function and identify new therapeutic targets for management of chronic inflammation in vascular settings

    Education’s not black and white, it’s vibrant grey

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    This paper offers a learner’s eye-view of a journey through education, written in an auto-narrative style. Sarah’s story spans from Secondary School to College and through University finishing at the point of Graduation. Revealed in this open and honest account is an insight to coping with home life whilst navigating the trials of the Education system. Sarah makes criticisms of her peers at every level reminding us how competitive some students have to be to get on and achieve success in their education. Critical judgements are also made about Sarah’s School teachers and University lecturers, which are at times as rewarding as they are uncomfortable, but always truthful. Consequently, there is much to learn by both academics and students from this sensitive and vulnerable personal revelation. Sarah’s evidence in turn points to some fundamental questions about the genuine outcomes of the Educational system, e.g. what are we actually teaching young people to be like? And do we like the product in terms of their values, beliefs and motives? A concluding message from Sarah’s perspective is that greater independence in learning, freedom in thinking and equipping people to reason, judge and make decisions in whatever realm, may be defining steps towards becoming educated
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