4,013 research outputs found

    LibQUAL+ in the UK: a brief report on the SCONUL Pilot.

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    Reports on the pilot year of LibQUAL+ in the UK adopted for trial by SCONUL Libraries. Discusses the implementation of LibQUAL+ and presents feedback from the UK participants. Concludes that the trial was a success and further iterations of the survey should be encouraged and supported

    The determination of the direction of the optic axis of uniaxial crystalline materials

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    The birefringence of crystalline substances in general, and of sapphire in particular, is described. A test is described whose purpose is to determine the direction of the optic axis of a cylindrically machined single crystal of sapphire. This test was performed on the NASA Lewis sapphire cylinder and it was found that the optic axis made an angle of 18 deg with the axis of symmetry of the cylinder

    Incident Beam Polarization for Laser Doppler Velocimetry Employing a Sapphire Cylindrical Window

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    For laser Doppler velocimetry studies employing sapphire windows as optical access ports, the birefringency of sapphire produces an extra beam intersection volume which serves to effectively smear the acquired velocity flow field data. It is shown that for a cylindrical window geometry, the extra beam intersection volume may be eliminated with minimal decrease in the fringe visibility of the remaining intersection volume by suitably orienting the polarizations of the initial laser beams. For horizontally incident beams, these polarizations were measured at three intersection locations within the cylinder. It was found that the measured polarization angles agreed with the theoretical predictions

    Enhanced coupling to microsphere resonances with optical fibers

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    Cataloged from PDF version of article.Morphology-dependent resonances (MDR's) of polystyrene microspheres were excited by an optical fiber coupler. For optical elimination of the air-cladding interface at the optical fiber coupler surface, the microsphere was immersed in an index-matching oil. MDR's were observed, even though the relative refractive index between the microsphere and the oil was only 1.09. The observed MDR spectra are in good agreement with the generalized Lorenz-Mie theory and the localization principle. The scattering efficiency into each MDR is estimated as a function of the impact parameter by means of generalized Lorenz-Mie theory. (C) 1997 Optical Society of America

    Mechanisms to Evade the Phagocyte Respiratory Burst Arose by Convergent Evolution in Typhoidal Salmonella Serovars.

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    Typhoid fever caused by Salmonella enterica serovar (S.) Typhi differs in its clinical presentation from gastroenteritis caused by S. Typhimurium and other non-typhoidal Salmonella serovars. The different clinical presentations are attributed in part to the virulence-associated capsular polysaccharide (Vi antigen) of S. Typhi, which prevents phagocytes from triggering a respiratory burst by preventing antibody-mediated complement activation. Paradoxically, the Vi antigen is absent from S. Paratyphi A, which causes a disease that is indistinguishable from typhoid fever. Here, we show that evasion of the phagocyte respiratory burst by S. Paratyphi A required very long O antigen chains containing the O2 antigen to inhibit antibody binding. We conclude that the ability to avoid the phagocyte respiratory burst is a property distinguishing typhoidal from non-typhoidal Salmonella serovars that was acquired by S. Typhi and S. Paratyphi A independently through convergent evolution

    Psychological Science In Cultural Context

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    When one understands psychological science To be a by-product of the Western tradition, fashioned by particular cultural and historical conditions, the door is opened to a fresh consideration of the practice of psychology in the global context. By using examples from experiences in Turkey, New Zealand, and India, the reader is sensitized first to the problems inherent in the unreflective exportation of Western psychology. To presume Western concepts of the mind, along with its methods of study, not only lends itself to research of little relevance to other cultures, bur disregards and undermines alternate cultural traditions. Against these tendencies toward a univocal science, the authors argue for a multicultural psychology-one that celebrates the rich multiplicity of indigenous conceptualizations of the person along with varying means of acquiring knowledge. To realize such a psychology, new forms of dialogue must be sought and the sharing made relevant to ongoing challenges of practical cultural significance

    Rainbow Scattering by a Coated Sphere

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    We examine the behavior of the first-order rainbow for a coated sphere by using both ray theory and Aden-Kerker wave theory as the radius of the core alpha12 and the thickness of the coating delta are varied. As the ratio delta/alpha12 increases from 10(-4) to 0.33, we find three classes of rainbow phenomena that cannot occur for a homogeneous-sphere rainbow. For delta/alpha12 less than or similar to 10(-3), the rainbow intensity is an oscillatory function of the coating thickness, for delta/alpha12 almost-equal-to 10(-2), the first-order rainbow breaks into a pair of twin rainbows, and for delta/alpha12 almost-equal-to 0.33, various rainbow-extinction transitions occur. Each of these effects is analyzed, and their physical interpretations are given. A Debye series decomposition of coated-sphere partial-wave scattering amplitudes is also performed and aids in the analysis

    Protocol for a national monthly survey of alcohol use in England with 6-month follow-up: 'The Alcohol Toolkit Study'.

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    Timely tracking of national patterns of alcohol consumption is needed to inform and evaluate strategies and policies aimed at reducing alcohol-related harm. Between 2014 until at least 2017, the Alcohol Toolkit Study (ATS) will provide such tracking data and link these with policy changes and campaigns. By virtue of its connection with the 'Smoking Toolkit Study' (STS), links will also be examined between alcohol and smoking-related behaviour
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