792 research outputs found
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The East Midlands in 2010
The East Midlands in 2010 is the updated evidence base that supports the regional economic strategy, A Flourishing Region. It presents a statistical portrait of the region covering demography, housing, economy & productivity, the labour market, deprivation & economic inclusion, transport, infrastructure & development, the environment and the spatial structure of the economy along with a series of sub-regional profiles
Tidal turbine blade load experiments for oscillatory motion
This paper presents blade root bending moment measurements of a horizontal-axis tidal turbine for planar oscillatory motion, conducted in a stationary water towing tank. By comparing the measurements with quasi-steady reconstructions for both single and multiple frequency oscillatory motion, the bending moment was shown to be sensitive to both frequency and amplitude, as well as to the mean tip-speed ratio. The unsteady loads associated with the separation of the flow and dynamic stall are shown to be of considerably greater importance than those which are already present for attached flow, such as added mass and dynamic inflow. A linear model fit to the unsteady bending moment also indicates that the inertia contribution is relatively small. For cases where attached flow exists over the majority of the load cycle, these reconstruction methods are likely to be sufficient to obtain a reasonable prediction of the root out-of-plane bending moment. However, turbines whose blades are likely to operate near stall are likely to require more complex models for accurate load predictions to mitigate the risk of fatigue failure
Experimental investigation into the post-filling stage of the resin infusion process
International audienceThe resin infusion process has developed as a low-cost method to produce large composite parts in low to medium quantities. Although the process is conceptually simple, the effects of many of the processing parameters on the post-filling stage of the process are not well understood. Most manufacturers tend to develop their approach to infusion process through trial and error, and then adhere to their 'secret recipe' without knowledge of the effect of each parameter. This paper describes an experimental investigation of the controllable process parameters and their effect on the final laminate composition, by monitoring local fluid pressure and full field laminate thickness data through the filling and post-filling stages. From the understanding of the effect of each parameter, guidelines are drawn to help manufacturers to optimise their process. The effect of using a 'brake' between the part and the vent are evaluated, and the benefits of turning the inlet into a vent at the onset of post-filling are highlighted together with methods of gaining some control on the final laminate fibre volume fraction
Kuiper Belt Object Occultations: Expected Rates, False Positives, and Survey Design
A novel method of generating artificial scintillation noise is developed and
used to evaluate occultation rates and false positive rates for surveys probing
the Kuiper Belt with the method of serendipitous stellar occultations. A
thorough examination of survey design shows that: (1) diffraction-dominated
occultations are critically (Nyquist) sampled at a rate of 2 Fsu^{-1},
corresponding to 40 s^{-1} for objects at 40 AU, (2) occultation detection
rates are maximized when targets are observed at solar opposition, (3) Main
Belt Asteroids will produce occultations lightcurves identical to those of
Kuiper Belt Objects if target stars are observed at solar elongations of: 116
deg < epsilon < 125 deg, or 131 deg < epsilon < 141 deg, and (4) genuine KBO
occultations are likely to be so rare that a detection threshold of >7-8 sigma
should be adopted to ensure that viable candidate events can be disentangled
from false positives.Comment: Accepted AJ, 12 pages, 12 figure
Simulation of the reinforcement compaction and resin flow during the complete resin infusion process
International audienceResin infusion (a.k.a. VARTM) is one of the LCM processes, for which liquid resin is drawn into dry reinforcements. Significant cavity thickness changes occur during processing, due to the flexibility of the vacuum bag used as one side of the tool, and the complex stress balance within the laminate. While the magnitude of thickness change is often small, the influence is significant on reinforcement properties. Changes in permeability during filling and post-filling have the potential to significantly affect the process. To simulate this behaviour, it is important to accurately model compaction and unloading of reinforcement in dry and wet states. A series of tests were completed to determine compaction behaviour of an isotropic glass fibre mat. From these tests several non-linear elastic compaction models have been determined, and applied within a resin infusion simulation which addresses pre-filling, filling and post-filling. This simulation was then used to assess different post-filling strategies
Strategies to Use Nanoparticles to Generate CD4 and CD8 Regulatory T Cells for the Treatment of SLE and Other Autoimmune Diseases
Autoimmune diseases are disorders of immune regulation where the mechanisms responsible for self-tolerance break down and pathologic T cells overcome the protective effects of T regulatory cells (Tregs) that normally control them. The result can be the initiation of chronic inflammatory diseases. Systemic lupus erythematosus (SLE) and other autoimmune diseases are generally treated with pharmacologic or biological agents that have broad suppressive effects. These agents can halt disease progression, yet rarely cure while carrying serious adverse side effects. Recently, nanoparticles have been engineered to correct homeostatic regulatory defects and regenerate therapeutic antigen-specific Tregs. Some approaches have used nanoparticles targeted to antigen presenting cells to switch their support from pathogenic T cells to protective Tregs. Others have used nanoparticles targeted directly to T cells for the induction and expansion of CD4+ and CD8+ Tregs. Some of these T cell targeted nanoparticles have been formulated to act as tolerogenic artificial antigen presenting cells. This article discusses the properties of these various nanoparticle formulations and the strategies to use them in the treatment of autoimmune diseases. The restoration and maintenance of Treg predominance over effector cells should promote long-term autoimmune disease remission and ultimately prevent them in susceptible individuals
Full field monitoring of the resin flow and laminate properties during the resin infusion process
International audienceThe resin infusion process (a.k.a. VARTM, SCRIMP) has developed as a low cost method for manufacturing large fibre reinforced plastic parts. This process still presents some challenges to industry with regards to reliability and repeatability, resulting in trial and error development being expensive and inefficient. This paper describes a fully instrumented resin infusion setup, providing preliminary experimental data acquired while varying influential parameters during the filling and post-filling stages. The laminate per-meability is a strong function of the fibre volume fraction which can be determined from the laminate thickness. To assess the variation of the volume fraction and permeability, full field thickness variations have been monitored using a digital speckle stereophotogrammetry system developed for this purpose. In-mould resin pressures, flow front progression, and incoming resin flow rate were also measured. A selection of four experiments is presented here for discussion
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A video life-world approach to consultation practice: The relevance of a socio-phenomenological approach
This article discusses the [development and] use of a video life-world schema to explore alternative orientations to the shared health consultation. It is anticipated that this schema can be used by practitioners and consumers alike to understand the dynamics of videoed health consultations, the role of the participants within it and the potential to consciously alter the outcome by altering behaviour during the process of interaction. The study examines health consultation participation and develops an interpretative method of analysis that includes image elicitation (via videos), phenomenology (to identify the components of the analytic framework), narrative (to depict the stories of interactions) and a reflexive mode (to develop shared meaning through a conceptual framework for analysis). The analytic framework is derived from a life-world conception of human mutual shared interaction which is presented here as a novel approach to understanding patient-centred care. The video materials used in this study were derived from consultations in a Walk-in Centre (WiC) in East London. The conceptual framework produced through the process of video analysis is comprised of different combinations of movement, knowledge and emotional conversations that are used to classify objective or engaged WiC health care interactions. The videoed interactions organise along an active or passive, facilitative or directive typical situation continuum illustrating different kinds of textual approaches to practice that are in tension or harmony. The schema demonstrates how practitioners and consumers interact to produce these outcomes and indicates the potential for both consumers and practitioners to be educated to develop practice dynamics that support patient-centred care and impact on health outcomes
The Joint European Compound Library:boosting precompetitive research
The Joint European Compound Library (JECL) is a new high-throughput screening collection aimed at driving precompetitive drug discovery and target validation. The JECL has been established with a core of over 321000 compounds from the proprietary collections of seven pharmaceutical companies and will expand to around 500000 compounds. Here, we analyse the physicochemical profile and chemical diversity of the core collection, showing that the collection is diverse and has a broad spectrum of predicted biological activity. We also describe a model for sharing compound information from multiple proprietary collections, enabling diversity and quality analysis without disclosing structures. The JECL is available for screening at no cost to European academic laboratories and SMEs through the IMI European Lead Factory (http://www.europeanleadfactory.eu/)
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