14,570 research outputs found

    Evaluation of a composite mobile holographic nondestructive test system

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    A simplified theoretical model for the interpretation of the double-exposure holographic interference fringe loci due to the general three-dimensional displacements was derived for the specific composite mobile holographic nondestructive test system. The model, representing a good approximation to a more tedious theoretical result, predicts that a combination of in-plane and out-of-plane displacements of the surface will produce concentric circular-shaped fringe patterns with locations of their center affected by the displacements. Appropriate experiments were designed and carried out for the test of the validity of the theory. These experiments include the taking of double-exposure holograms of in-plane translations and combined in-plane and out-of-plane translations. The simplified model agreed quite well with the experimental results. Experimentally observed effects due to the curvature of the test plate and the variations of the angles of incidence of the laser light suggest that in order for the simplified model to be able to predict the test results more accurately, incidence and reflection of the laser light should be chosen as nearly perpendicular to the surface of the tested object as possible

    Evidence for CO2-rich fluids in rocks from the type charnockite area near Pallavaram, Tamil Nadu

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    Fluid inclusion and mineral chemistry data was presented for samples from the type charnockite area near Pallavaram (Tamil Nadu, India). The results indicate the presence of a dense CO2 fluid phase, but the data cannot distinguish between influx of this fluid from elsewhere or localized migration of CO2-rich fluids associated with dehydration melting

    The supermassive black hole mass - S\'ersic index relations for bulges and elliptical galaxies

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    Scaling relations between supermassive black hole mass, M_BH, and host galaxy properties are a powerful instrument for studying their coevolution. A complete picture involving all of the black hole scaling relations, in which each relation is consistent with the others, is necessary to fully understand the black hole-galaxy connection. The relation between M_BH and the central light concentration of the surrounding bulge, quantified by the S\'ersic index n, may be one of the simplest and strongest such relations, requiring only uncalibrated galaxy images. We have conducted a census of literature S\'ersic index measurements for a sample of 54 local galaxies with directly measured M_BH values. We find a clear M_BH - n relation, despite an appreciable level of scatter due to the heterogeneity of the data. Given the current M_BH - L_sph and the L_sph - n relations, we have additionally derived the expected M_BH - n relations, which are marginally consistent at the 2 sigma level with the observed relations. Elliptical galaxies and the bulges of disc galaxies are each expected to follow two distinct bent M_BH - n relations due to the S\'ersic/core-S\'ersic divide. For the same central light concentration, we predict that M_BH in the S\'ersic bulges of disc galaxies are an order magnitude higher than in S\'ersic elliptical galaxies if they follow the same M_BH - L_sph relation.Comment: 12 pages, 6 figures, 5 tables, accepted for publication in MNRA

    Tracking pupil mobility over the pre-school and primary school period: evidence from EPPE 3-11

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    This report describes the ‘tracking’ of the EPPE 3-11 sample and then goes on to examine the possible influence of mobility on EPPE 3-11 children’s cognitive progress and social/behavioural development over both the pre-school and primary school period. In the present research ‘mobility’ is defined as having changed pre-school or school centre at least once. The aims of the research are: • To determine possible means of reducing attrition in a longitudinal sample - tracking • To identify any likely predictors of mobility, that is, whether mobile individuals share any defining characteristics; • To investigate the effects of mobility when predicting children’s cognitive and social/behavioural outcomes, controlling for other background factors; • To investigate the effects of children’s mobility in terms of the academic effectiveness of the schools attended and to which children moved

    Evaluating the clinical and economic burden of healthcare-associated infections during hospitalization for surgery in France

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    Over 4 million patients suffer nosocomial infections annually in the European Union. This study aimed to estimate the healthcare burden associated with healthcare-associated infections (HAIs) following surgery in France, and explore the potential impact of infection control strategies and interventions on the clinical and economic burden of disease. Data on the frequency of HAIs were gathered from the 2010 Programme de Médicalisation des Systèmes d'Information (PMSI), and cost data were taken from the 2009 Echelle Nationale de Coûts à Méthodologie Commune (ENCC). It was estimated that 3% of surgical procedures performed in 2010 in France resulted in infection, resulting in an annual cost of €57892715. Patients experiencing a HAI had a significantly increased mortality risk (4·15-fold) and an increased length of hospital stay (threefold). Scenario analysis in which HAI incidence following surgery was reduced by 8% (based on a study of the effectiveness of triclosan-coated sutures), suggested that, annually, 20205 hospital days and €4588519 could be saved. Analyses of 20% and 30% reductions in incidence (based on an estimate of the number of preventable nosocomial infections) suggested that annual savings of €11548057 and €17334696, respectively, could be made. New infection control interventions which reduce HAI incidence during hospitalization for surgery have the potential to provide valuable cost savings to healthcare provider

    An acoustic charge transport imager for high definition television applications

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    The primary goal of this research is to develop a solid-state television (HDTV) imager chip operating at a frame rate of about 170 frames/sec at 2 Megapixels/frame. This imager will offer an order of magnitude improvements in speed over CCD designs and will allow for monolithic imagers operating from the IR to UV. The technical approach of the project focuses on the development of the three basic components of the imager and their subsequent integration. The camera chip can be divided into three distinct functions: (1) image capture via an array of avalanche photodiodes (APD's); (2) charge collection, storage, and overflow control via a charge transfer transistor device (CTD); and (3) charge readout via an array of acoustic charge transport (ACT) channels. The use of APD's allows for front end gain at low noise and low operating voltages while the ACT readout enables concomitant high speed and high charge transfer efficiency. Currently work is progressing towards the optimization of each of these component devices. In addition to the development of each of the three distinct components, work towards their integration and manufacturability is also progressing. The component designs are considered not only to meet individual specifications but to provide overall system level performance suitable for HDTV operation upon integration. The ultimate manufacturability and reliability of the chip constrains the design as well. The progress made during this period is described in detail

    Herschel observations of gamma-ray burst host galaxies: implications for the topology of the dusty interstellar medium

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    Long-duration gamma-ray bursts (GRBs) are indisputably related to star formation, and their vast luminosity in gamma rays pin-points regions of star formation independent of galaxy mass. As such, GRBs provide a unique tool for studying star forming galaxies out to high-z independent of luminosity. Most of our understanding of the properties of GRB hosts (GRBHs) comes from optical and near-infrared (NIR) follow-up observations, and we therefore have relatively little knowledge of the fraction of dust-enshrouded star formation that resides within GRBHs. Currently ~20% of GRBs show evidence of significant amounts of dust along the line of sight to the afterglow through the host galaxy, and these GRBs tend to reside within redder and more massive galaxies than GRBs with optically bright afterglows. In this paper we present Herschel observations of five GRBHs with evidence of being dust-rich, targeted to understand the dust attenuation properties within GRBs better. Despite the sensitivity of our Herschel observations, only one galaxy in our sample was detected (GRBH 070306), for which we measure a total star formation rate (SFR) of ~100Mstar/yr, and which had a relatively high stellar mass (log[Mstar]=10.34+0.09/-0.04). Nevertheless, when considering a larger sample of GRBHs observed with Herschel, it is clear that stellar mass is not the only factor contributing to a Herschel detection, and significant dust extinction along the GRB sightline (A_{V,GRB}>1.5~mag) appears to be a considerably better tracer of GRBHs with high dust mass. This suggests that the extinguishing dust along the GRB line of sight lies predominantly within the host galaxy ISM, and thus those GRBs with A_{V,GRB}>1~mag but with no host galaxy Herschel detections are likely to have been predominantly extinguished by dust within an intervening dense cloud.Comment: 14 pages, 7 figures. Accepted for publication in A&

    Written Speech Feedback in the Basic Communication Course: Are Instructors too Polite?

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    The present study investigates written performance feedback through the lens of politeness theory. Study 1 examined the types of comments instructors offer to students when they provide written feedback on speeches as well as the relationship between these comments and students\u27 grades. Results demonstrate that instructors used an overabundance of positive politeness messages and virtually no negative politeness messages. Students who received a higher grade were more likely to receive fewer face threats and more positive politeness messages than those students\u27 who received a lower grade. The results also suggest that instructors are more willing to threaten a students\u27 negative face than their positive face. Study 2 extended the research project by examining students\u27 perceptions of instructor feedback students deem the most helpful. Results indicate that students desire a balance between their grade and the number of positive politeness comments they receive as well as more comments that threaten their face. Students in this study also found specific written feedback as the most helpful type of feedback they received
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