2,562 research outputs found

    B2B Infrastructures in the Process of Drug Discovery and Healthcare

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    In this paper we describe a demonstration of an innovative B2B infrastructure which can be used to support collaborations in the pharmaceutical industry to achieve the drug discovery goal. Based on experience gained in a wide range of collaborative projects in the areas of grid technology, semantics and data management we show future work and new topics in B2B infrastructures which arise when considering the use of patient records in the process of drug discovery and in healthcare applications

    Optical anisotropy of Ge(001)2x1

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    We have measured the change in the optical reflection anisotropy of a clean Ge(001) surface upon exposure to molecular oxygen up to saturation coverage. Both phase and amplitude changes have been recorded with a normal-incidence ellipsometer. They have been found to be related by a Kramers-Kronig transformation. The change in the complex reflection ratio could be interpreted as an anisotropy of the clean Ge(001)2 × 1 surface dielectric function, using a three-layer McIntyre-Aspnes approach and neglecting the oxygen overlayer. The surface dielectric function anisotropy can be described fairly well by optical selection rules, based on symmetry arguments. This model was applied to the possible optical transitions at this surface between filled dimers, dangling bonds and back-bonds and the empty dangling bonds and dimers

    Role of COX-1 and COX-2 in the release of prostanoids in murine lung and isolated lung fibroblasts

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    Cyclooxygenase (COX) is the first enzyme in the conversion of arachidonic acid to prostanoids. There are two isoforms of COX; COX-1, which is constitutively expressed with a homeostatic role in most tissues, and COX-2, which while constitutively expressed in some discreet sites is generally inducible by growth factors and during inflammation. In the current study, we have used tissues and cells from knock-out mice to investigate the relative contributions of COX-1 and COX-2 to PGE2 production by lung tissue ex vivo and by proliferating lung fibroblasts in vitro. Lung tissues from WT (C57Bl6), COX-1-/- and COX-2-/- mice were immediately dissected (<15 min after death) and incubated (37 °C) for 30 min in DMEM containing 50 µM calcium ionophore (A23187). Release of PGE2 was determined by competitive immunoassay. In parallel studies, murine lung fibroblasts from COX-1-/- and COX-2-/- mice were explanted and cultured before being seeded in 96-well plates at sub-confluence (5000-8000/well) and incubated for 24-48 hours in the presence of 10% FCS. Accumulated release of PGE2 was then measured as above. Over 30 min PGE2 was released by lung pieces from wild type (1117 ± 55 pg/ml) and COX-2-/- (2013 ± 255 pg/ml) but not from COX-1-/- (<61pg/ml) mice (n=4). In contrast, proliferating lung fibroblasts from COX-1-/- (4978.9 ± 1392 pg/ml) mice released higher levels of PGE2 than cells from COX-2-/- (1194 ± 617 ng/ml) mice (n=4 using cells from 2-3 separate mice for each genotype). These results show that COX-1 activity underpins the stimulated release of PGE2 in healthy mouse lung tissue. Conversely, COX-2 activity predominates in proliferating lung fibroblasts, which may be important as COX-derived PGE2 mediates proliferation of lung fibroblasts (Trends Immunol.2004;25(1):40-6). Our results suggest a switch in COX isoform in lung cells during proliferation which could be relevant to our understanding of conditions such as idiopathic pulmonary fibrosis.Non peer reviewedFinal Accepted Versio

    The relationship between local scalp skin temperature and cutaneous perfusion during scalp cooling

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    Cooling the scalp during administration of chemotherapy can prevent hair loss. It reduces both skin blood flow and hair follicle temperature, thus affecting drug supply and drug effect in the hair follicle. The extent to which these mechanisms contribute to the hair preservative effect of scalp cooling remains unknown. The purpose of this study was to establish a relationship between local scalp skin temperature and cutaneous blood flow during scalp cooling. We measured skin temperature and cutaneous perfusion during a cooling and re-warming experiment. Experiments on a single subject showed that the measurements were reproducible and that the response was identical for the two positions that were measured. Inter-subject variability was investigated on nine subjects. We found that for the first 10 °C of cooling, perfusion of the scalp skin decreases to below 40%. Perfusion can be further reduced to below 30% by a few degrees more cooling, but a plateau is reached after that. We found that a generally accepted relation in thermal physiology between temperature and perfusion (i.e. Q10 relation) does not describe the data well, but we found an alternative relation that describes the average behavior significantly better

    The influence of cam geometry and operating conditions on chaotic mixing of viscous fluids in a twin cam mixer

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    Smooth particle hydrodynamica (SPH) simulations were used to better understand the mixing performance of a class of two-dimensional Twin Cam mixers. The chaotic manifolds of the flow are used to describe the mixing and to identify isolated regions. For an equilateral triangle cam geometry, a figure-eight manifold structure traps a layer of fluid against the cam boundaries. Changes in the differential rotation and phase offsets between the cams results in modest improvements in the mixing rate across the manifold barrier. Reducing the apex angle of the triangle changes the manifold structure and allows the trapped layer of fluid to mix more effectively with the rest of the domain. This article shows that examining the chaotic manifolds within a typical industrial mixer can provide valuable insight into both the transient and long-term mixing processes, leading to a more focused exploration of possible mixer configurations and to practical improvements in mixing efficienc

    Microstructural characterisation of TiAlTiAu and TiAlPdAu ohmic contacts to AlGaN/GaN

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    Ti/Al/Ti/Au and Ti/Al/Pd/Au contacts to AlGaN/GaN have been investigated to ascertain the effect of annealing temperature on the structural evolution of the contacts. Ti/Al/Ti/Au contacts become ohmic after rapid thermal annealing at 750°C or higher, corresponding to the formation of an interfacial TiN phase, with inclusions penetrating through the AlGaN layer observed after annealing at 950°C. The Pd layer is shown to be more efficient at inhibiting diffusion of Au to the interface than Ti. Ohmic behaviour was not seen with the Ti/Al/Pd/Au scheme. Either the presence of Au at the interface may improve ohmic behaviour, or the Ti:Al ratio is insufficient in this scheme

    Paying primary health care centers for performance in Rwanda

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    Paying for performance (P4P) provides financial incentives for providers to increase the use and quality of care. P4P can affect health care by providing incentives for providers to put more effort into specific activities, and by increasing the amount of resources available to finance the delivery of services. This paper evaluates the impact of P4P on the use and quality of prenatal, institutional delivery, and child preventive care using data produced from a prospective quasi-experimental evaluation nested into the national rollout of P4P in Rwanda. Treatment facilities were enrolled in the P4P scheme in 2006 and comparison facilities were enrolled two years later. The incentive effect is isolated from the resource effect by increasing comparison facilities'input-based budgets by the average P4P payments to the treatment facilities. The data were collected from 166 facilities and a random sample of 2158 households. P4P had a large and significant positive impact on institutional deliveries and preventive care visits by young children, and improved quality of prenatal care. The authors find no effect on the number of prenatal care visits or on immunization rates. P4P had the greatest effect on those services that had the highest payment rates and needed the lowest provider effort. P4P financial performance incentives can improve both the use of and the quality of health services. Because the analysis isolates the incentive effect from the resource effect in P4P, the results indicate that an equal amount of financial resources without the incentives would not have achieved the same gain in outcomes.Health Monitoring&Evaluation,Population Policies,Health Systems Development&Reform,Disease Control&Prevention,Adolescent Health
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