1,230 research outputs found

    Report of the Integrated Stroke Care Workshop

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    The Stroke Project has been underway since October 2000. This workshop represented the first mechanism where by issues surrounding the project have been addressed by the multi- disciplinary stroke team and the Darent Valley Hospital Staff. Approximately 35 members of staff attended the workshop, demonstrating the high level of interest and ownership. Currently, the hospital receives an average eight or nine new stroke admissions a week. The turnover is such that patients suffering from stroke account for around 22-23 occupied beds in the acute hospital at any point in time. In the past the Acute Trust had had a lead Stroke Physician responsible for 20 designated stroke beds within a stroke unit. In that system many (but not all) cases of acute stroke admitted under the General Physicians would have been referred to the stroke unit and had their acute care and acute rehabilitation provided on site in that unit. At that time the overall number of beds occupied by cases of stroke was around 28- 29

    Whey- vs Casein-Based Enteral Formula and Gastrointestinal Function in Children With Cerebral Palsy.

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    Objectives: Children with severe cerebral palsy (CP) commonly have gastrointestinal (GI) dysfunction. Whey-based enteral formulas have been postulated to reduce gastroesophageal reflux (GOR) and accelerate gastric emptying (GE). The authors investigated whether whey-based (vs casein-based) enteral formulas reduce GOR and accelerate GE in children who have severe CP with a gastrostomy and fundoplication. Methods: Thirteen children received a casein-based formula for 1 week and either a 50% whey whole protein (50% WWP) or a 100% whey partially hydrolyzed protein (100% WPHP) formula for 1 week. Reflux episodes, gastric half-emptying time (GE t1/2), and reported pain and GI symptoms were measured. Results: Whey formulas emptied significantly faster than casein (median [interquartile range (IQR)] GE t1/2, 33.9 [25.3-166.2] min vs 56.6 [46-191] min; P = .033). Reflux parameters were unchanged. GI symptoms were lower in children who received 50% WWP (visual analog symptom score, median [IQR], 0[0-11.8]) vs 100% WPHP (13.0 [2.5-24.8]) (P = .035). Conclusion: This pilot study shows that in children who have severe CP with a gastrostomy and fundoplication, GE of the whey-based enteral formula is significantly faster than casein. The acceleration in GE does not alter GOR frequency, and there appears to be no effect of whey vs casein in reducing acid, nonacid, and total reflux episodes. The results indicate that enteral formula selection may be particularly important for children with severe CP and delayed GE. (JPEN J Parenter Enteral Nutr. 2012;36:118S-123S

    An experimental study of airfoil instability tonal noise with trailing edge serrations

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    This paper presents an experimental study of the effect of trailing edge serrations on airfoil instability noise. Detailed aeroacoustic measurements are presented of the noise radiated by an NACA-0012 airfoil with trailing edge serrations in a low to moderate speed flow under acoustical free field conditions. The existence of a separated boundary layer near the trailing edge of the airfoil at an angle of attack of 4.2 degree has been experimentally identified by a surface mounted hot-film arrays technique. Hot-wire results have shown that the saw-tooth surface can trigger a bypass transition and prevent the boundary layer from becoming separated. Without the separated boundary layer to act as an amplifier for the incoming Tollmien-Schlichting waves, the intensity and spectral characteristic of the radiated tonal noise can be affected depending upon the serration geometry. Particle Imaging Velocimetry (PIV) measurements of the airfoil wakes for a straight and serrated trailing edge are also reported in this paper. These measurements show that localized normal-component velocity fluctuations that are present in a small region of the wake from the laminar airfoil become weakened once serrations are introduced. Owing to the above unique characteristics of the serrated trailing edges, we are able to further investigate the mechanisms of airfoil instability tonal noise with special emphasis on the assessment of the wake and non-wake based aeroacoustic feedback model. It has been shown that the instability tonal noise generated at an angle of attack below approximately one degree could involve several complex mechanisms. On the other hand, the non-wake based aeroacoustic feedback mechanism alone is sufficient to predict all discrete tone frequencies accurately when the airfoil is at a moderate angle of attack

    Effect of the non-linear magnetic fields on the emittance growth in the ATF extraction line

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    WE6PFP075International audienceSince several years, the vertical beam emittance measured in the Extraction Line (EXT) of the Accelerator Test Facility (ATF) at KEK, has been signiïŹcantly larger than that measured in the damping ring (DR) itself. The EXT line that transports the beam to the ATF2 Final Focus beam line has been rebuilt, but the extraction itself remains in most part unchanged, with the extracted beam transported oïŹ€- axis horizontally in two of the quadrupoles, beyond the linear region for one of them. A few other nearby magnets have also modelled or measured non-linearity. In case of a residual vertical beam displacement, this can result in increased vertical emittance through coupling between the two transverse planes. Tracking studies as well as measurements have been carried out to study this eïŹ€ect and the induced sensitivity of beam optical parameters to the trajectory at injection, in view of deriving tolerances for reproducible and stable operation

    Universal symmetry-breaking dynamics for the Kerr interaction of counterpropagating light in dielectric ring resonators

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    Spontaneous symmetry breaking is an important concept in many areas of physics. A fundamentally simple symmetry-breaking mechanism in electrodynamics occurs between counterpropagating electromagnetic waves in ring resonators, mediated by the Kerr nonlinearity. The interaction of counterpropagating light in bidirectionally pumped microresonators finds application in the realization of optical nonreciprocity (for optical diodes), studies of PT-symmetric systems, and the generation of counterpropagating solitons. Here, we present comprehensive analytical and dynamical models for the nonlinear Kerr interaction of counterpropagating light in a dielectric ring resonator. In particular, we study discontinuous behavior in the onset of spontaneous symmetry breaking, indicating divergent sensitivity to small external perturbations. These results can be applied to realize, for example, highly sensitive near-field or rotation sensors. We then generalize to a time-dependent model, which predicts different types of dynamical behavior, including oscillatory regimes that could enable Kerr-nonlinearity-driven all-optical oscillators. The physics of our model can be applied to other systems featuring Kerr-type interaction between two distinct modes, such as for light of opposite circular polarization in nonlinear resonators, which are commonly described by coupled Lugiato-Lefever equations

    Coral Disease and Health Workshop: Coral Histopathology II

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    The health and continued existence of coral reef ecosystems are threatened by an increasing array of environmental and anthropogenic impacts. Coral disease is one of the prominent causes of increased mortality among reefs globally, particularly in the Caribbean. Although over 40 different coral diseases and syndromes have been reported worldwide, only a few etiological agents have been confirmed; most pathogens remain unknown and the dynamics of disease transmission, pathogenicity and mortality are not understood. Causal relationships have been documented for only a few of the coral diseases, while new syndromes continue to emerge. Extensive field observations by coral biologists have provided substantial documentation of a plethora of new pathologies, but our understanding, however, has been limited to descriptions of gross lesions with names reflecting these observations (e.g., black band, white band, dark spot). To determine etiology, we must equip coral diseases scientists with basic biomedical knowledge and specialized training in areas such as histology, cell biology and pathology. Only through combining descriptive science with mechanistic science and employing the synthesis epizootiology provides will we be able to gain insight into causation and become equipped to handle the pending crisis. One of the critical challenges faced by coral disease researchers is to establish a framework to systematically study coral pathologies drawing from the field of diagnostic medicine and pathology and using generally accepted nomenclature. This process began in April 2004, with a workshop titled Coral Disease and Health Workshop: Developing Diagnostic Criteria co-convened by the Coral Disease and Health Consortium (CDHC), a working group organized under the auspices of the U.S. Coral Reef Task Force, and the International Registry for Coral Pathology (IRCP). The workshop was hosted by the U.S. Geological Survey, National Wildlife Health Center (NWHC) in Madison, Wisconsin and was focused on gross morphology and disease signs observed in the field. A resounding recommendation from the histopathologists participating in the workshop was the urgent need to develop diagnostic criteria that are suitable to move from gross observations to morphological diagnoses based on evaluation of microscopic anatomy. (PDF contains 92 pages

    PKCÎŽ Clustering at the Leading Edge and Mediating Growth Factor-Enhanced, but not ECM-Initiated, Dermal Fibroblast Migration

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    We have previously shown that the immobilized extracellular matrices (ECMs) initiate cell migration and soluble growth factors (GFs) further enhance ECM-initiated cell migration. GFs alone cannot initiate cell migration. To further investigate the specificity of the two signaling mechanisms, we focused on the protein kinase C (PKC) family genes in primary human dermal fibroblasts (DFs). We here show that platelet-derived growth factor-BB (PDGF-BB) strongly stimulates membrane translocation and leading edge clustering of protein kinase CÎŽ (PKCÎŽ). In contrast, attachment to collagen matrix alone does not cause the translocation. Although the kinase function of PKCÎŽ is dispensable for initial membrane translocation, it is critical for its sustained presence at the cells's leading edge. Blockade of endogenous PKCÎŽ signaling with dominant-negative kinase-defective PKC (PKCÎŽ-KD) or PKCÎŽ-small interfering RNA (siRNA) completely inhibited PDGF-BB-stimulated DF migration. In contrast, neither PKCÎŽ-KD nor PKCÎŽ-siRNA affected collagen-induced initiation of DF migration. Overexpression of a constitutively activated PKCÎŽ (PKCÎŽ-R144/145A) partially mimics the effect of PDGF-BB. However, PKCÎŽ-KD, PKCÎŽ-siRNA, or PKCÎŽ-R144/145A does not affect PDGF-BB-stimulated activation of p38 mitogen-activated protein kinase, extracellular signal-regulated kinase1/2, or c-Jun N-terminal kinase. Instead, inhibition of PKCÎŽ blocks PDGF-BB-stimulated activation of signal transducer and activator of transcription 3 (Stat3). This study unveiled the specificity of PKCÎŽ in the control of DF migration

    Understanding How Headings Influence Text Processing

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    Titles and headings are commonly used signaling devices in expository texts. Researchers in cognitive and educational psychology have demonstrated several important effects of headings and titles on text processing: headings improve memory for text organization; headings influence text comprehension by activating readers’ prior knowledge; and titles can bias text comprehension by their emphasis on a particular text topic. However, the lack of precise linguistic analyses of titles/headings has limited both the scope of empirical research and the precision of conclusions. We present a theory of signaling devices that provides a detailed analysis of variation in titles and headings and generates predictions concerning their effects. We discuss the implications of our analyses for research on titles and headings and summarize recent research findings that illustrate the validity of a central component of our analyses. Finally, we propose some future research directions integrating insights from linguistics for the study of how headings and titles affect text processing.Les titres et intertitres sont des dispositifs de signalisation frĂ©quemment utilisĂ©s dans les textes expositifs. De nombreuses recherches rĂ©alisĂ©es en psychologie cognitive et psychologie des apprentissages ont mis en Ă©vidence leurs effets sur le traitement du texte par le lecteur : les intertitres amĂ©liorent la reprĂ©sentation mnĂ©sique de l’organisation du texte et influencent la comprĂ©hension du texte par un mĂ©canisme d’activation des connaissances antĂ©rieures du lecteur. Les titres gĂ©nĂ©raux, lorsqu’ils mettent en avant un des thĂšmes du texte, biaisent la comprĂ©hension du texte. Cependant, l’absence d’analyse linguistique approfondie des titres et intertitres a limitĂ© la portĂ©e de ces travaux et a menĂ© Ă  des conclusions mĂ©ritant d’ĂȘtre affinĂ©es. Nous prĂ©sentons une thĂ©orie gĂ©nĂ©rale de la signalisation des textes qui propose un cadre d’analyse dĂ©taillĂ© de la variabilitĂ© des titres et intertitres et gĂ©nĂšre des prĂ©dictions quant Ă  leurs effets. Nous discutons les implications de ce cadre pour la recherche sur les titres et intertitres. Nous rĂ©sumons des rĂ©sultats rĂ©cents qui illustrent la validitĂ© d’une composante centrale de nos analyses. Enfin, nous proposons des perspectives de recherche intĂ©grant des rĂ©sultats de travaux en linguistique pour l’étude des effets des titres et intertitres sur le traitement cognitif du texte
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