842 resultados para CLUSTER TURNOFFS
Resumo:
Predicting from first-principles calculations whether mixed metallic elements phase-separate or form ordered structures is a major challenge of current materials research. It can be partially addressed in cases where experiments suggest the underlying lattice is conserved, using cluster expansion (CE) and a variety of exhaustive evaluation or genetic search algorithms. Evolutionary algorithms have been recently introduced to search for stable off-lattice structures at fixed mixture compositions. The general off-lattice problem is still unsolved. We present an integrated approach of CE and high-throughput ab initio calculations (HT) applicable to the full range of compositions in binary systems where the constituent elements or the intermediate ordered structures have different lattice types. The HT method replaces the search algorithms by direct calculation of a moderate number of naturally occurring prototypes representing all crystal systems and guides CE calculations of derivative structures. This synergy achieves the precision of the CE and the guiding strengths of the HT. Its application to poorly characterized binary Hf systems, believed to be phase-separating, defines three classes of alloys where CE and HT complement each other to uncover new ordered structures.
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BACKGROUND: Many patients with diabetes have poor blood pressure (BP) control. Pharmacological therapy is the cornerstone of effective BP treatment, yet there are high rates both of poor medication adherence and failure to intensify medications. Successful medication management requires an effective partnership between providers who initiate and increase doses of effective medications and patients who adhere to the regimen. METHODS: In this cluster-randomized controlled effectiveness study, primary care teams within sites were randomized to a program led by a clinical pharmacist trained in motivational interviewing-based behavioral counseling approaches and authorized to make BP medication changes or to usual care. This study involved the collection of data during a 14-month intervention period in three Department of Veterans Affairs facilities and two Kaiser Permanente Northern California facilities. The clinical pharmacist was supported by clinical information systems that enabled proactive identification of, and outreach to, eligible patients identified on the basis of poor BP control and either medication refill gaps or lack of recent medication intensification. The primary outcome is the relative change in systolic blood pressure (SBP) measurements over time. Secondary outcomes are changes in Hemoglobin A1c, low-density lipoprotein cholesterol (LDL), medication adherence determined from pharmacy refill data, and medication intensification rates. DISCUSSION: Integration of the three intervention elements--proactive identification, adherence counseling and medication intensification--is essential to achieve optimal levels of control for high-risk patients. Testing the effectiveness of this intervention at the team level allows us to study the program as it would typically be implemented within a clinic setting, including how it integrates with other elements of care. TRIAL REGISTRATION: The ClinicalTrials.gov registration number is NCT00495794.
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Magnetic compass orientation in a night-migratory songbird requires that Cluster N, a cluster of forebrain regions, is functional. Cluster N, which receives input from the eyes via the thalamofugal pathway, shows high neuronal activity in night-migrants performing magnetic compass-guided behaviour at night, whereas no activation is observed during the day, and covering up the birds' eyes strongly reduces neuronal activation. These findings suggest that Cluster N processes light-dependent magnetic compass information in night-migrating songbirds. The aim of this study was to test if Cluster N is active during daytime migration. We used behavioural molecular mapping based on ZENK activation to investigate if Cluster N is active in the meadow pipit (Anthus pratensis), a day- and night-migratory species. We found that Cluster N of meadow pipits shows high neuronal activity under dim-light at night, but not under full room-light conditions during the day. These data suggest that, in day- and night-migratory meadow pipits, the light-dependent magnetic compass, which requires an active Cluster N, may only be used during night-time, whereas another magnetosensory mechanism and/or other reference system(s), like the sun or polarized light, may be used as primary orientation cues during the day.
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The Hyades stream has long been thought to be a dispersed vestige of the Hyades cluster. However, recent analyses of the parallax distribution, of the mass function, and of the action-space distribution of stream stars have shown it to be rather composed of orbits trapped at a resonance of a density disturbance. This resonant scenario should leave a clearly different signature in the element abundances of stream stars than the dispersed cluster scenario, since the Hyades cluster is chemically homogeneous. Here, we study the metallicity as well as the element abundances of Li, Na, Mg, Fe, Zr, Ba, La, Ce, Nd and Eu for a random sample of stars belonging to the Hyades stream, and compare them with those of stars from the Hyades cluster. From this analysis: (i) we independently confirm that the Hyades stream cannot be solely composed of stars originating in the Hyades cluster; (ii) we show thatsomestars (namely 2/21) from the Hyades stream nevertheless have abundances compatible with an origin in the cluster; (iii) we emphasize that the use of Li as a chemical tag of the cluster origin of main-sequence stars is very efficient in the range 5500K ≤Teff≤ 6200K, since the Li sequence in the Hyades cluster is very tight, while at the same time spanning a large abundance range; (iv) we show that, while this evaporated population has a metallicity excess of ~0.2 dex with respect to the local thin-disc population, identical to that of the Hyades cluster, the remainder of the Hyades stream population has still a metallicity excess of ~0.06-0.15 dex, consistent with an origin in the inner Galaxy and (v) we show that the Hyades stream can be interpreted as an inner 4:1 resonance of the spiral pattern: this then also reproduces an orbital family compatible with the Sirius stream, and places the origin of the Hyades stream up to 1kpc inwards from the solar radius, which might explain the observed metallicity excess of the stream population. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.
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This paper is part of a collaborative project being undertaken by the three leading universities of Brussels, VUB, ULB and USL-B supported by Innnoviris. The project called Media Clusters Brussels - MCB - started in October 2014 with the goal to analyze the development of a Media Park around the two public broadcasters at the site of Reyers in Brussels being host of a media cluster in the capital city. Not only policymakers but also many authors recognized in the last decade that the media industry is characterized from a geographical point of view by a heavy concentration to a limited number of large cities, where media clusters have emerged (Karlsson & Picard, 2011). The common assumption about media clusters is that locating inside a regional agglomeration of related actors brings advantages for these firms. Especially, the interrelations and interactions between the actors on a social level matter for the shape and efficiency of the agglomerations (Picard, 2008). However, even though the importance of the actors and their interrelations has been a common assumption, many authors solely focus on the macro-economical aspects of the clusters. Within this paper, we propose to realize a socio-economical analysis of media clusters to make informed decisions in the development and so, bring the social (human) factor back into scope. Therefore, this article focuses on the development of a novel valuable framework, the so-called 7P framework with a multilevel and interdisciplinary approach, which includes three aspects, which have been identified as emerging success-factors of media clusters: partnerships, (media) professionals and positive spillovers.
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El azúcar es un commodity específico y uno de los mayores contribuyentes al producto interno bruto agrícola de los países en desarrollo para el consumo interno y el comercio internacional. A nivel mundial, el azúcar es obtenido industrialmente a partir de remolacha azucarera (Beta vulgaris) y de la caña de azúcar (Saccharum officinarum) como las únicas fuentes importantes para el comercio (...). El mercado internacional del azúcar es uno de los mercados de commodities agrícolas más altamente distorsionado. El comercio del azúcar crudo y refinado se caracteriza en general, por la ayuda interna significativa y generalizada, y algunas políticas que distorsionan el mercado como: pagos mínimos garantizados a productores, controles de producción y comercialización, regulación de precios, aranceles, cuotas de importación y subvenciones a la exportación (...). A nivel general, se pueden distinguir, básicamente, dos tipos de mercados de azúcar: el mercado protegido y el mercado libre. El mercado protegido consiste en acuerdos preferenciales y contratos de largo plazo que incluyen el sistema de cuotas entre diferentes países. En general, los precios del azúcar presentan fuertes fluctuaciones que obedecen a factores económicos, especulaciones, cambios políticos, recesiones y efectos climáticos (...). No obstante lo anterior, en los últimos años se ha observado una clara tendencia a la globalización de los mercados, y mercado del azúcar no es la excepción. Recientemente, se han centrado esfuerzos para liberalizar parcialmente algunos de los mercados más importantes, como es el caso de EEUU, la UE, Brasil y Australia (...). La creciente demanda de fuentes de energía renovable, entre las cuales se destacan los biocombustibles, también ha afectado significativamente la dinámica comercial y productiva de algunos sectores, en particular el sector azucarero. La caña de azúcar, se ha constituido en la principal materia prima para la elaboración de bioetanol, por lo cual, los países productores han experimentado un reciente cambio en su estructura productiva y comercial, buscando productos de mayor valor agregado, a fin de mejorar su posición competitiva. Bajo este esquema, las industrias productoras de azúcar, sobretodo en países en desarrollo enfrenta enormes retos para convertir sus ventajas comparativas en ventajas competitivas. La estructura de los costos de producción y el rendimiento de cada industria azucarera domestica son unos de los principales impulsores de su competitividad, la determinación de los futuros centros de la producción y el crecimiento de las exportaciones. En medio de este contexto, el presente estudio aborda los principales determinantes de la competitividad de la industria azucarera en Colombia, concentrada en un 98,07 por ciento en el cluster del valle geográfico del rio Cauca.
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This paper discusses load-balancing issues when using heterogeneous cluster computers. There is a growing trend towards the use of commodity microprocessor clusters. Although today's microprocessors have reached a theoretical peak performance in the range of one GFLOPS/s, heterogeneous clusters of commodity processors are amongst the most challenging parallel systems to programme efficiently. We will outline an approach for optimising the performance of parallel mesh-based applications for heterogeneous cluster computers and present case studies with the GeoFEM code. The focus is on application cost monitoring and load balancing using the DRAMA library.
Resumo:
The factors that are driving the development and use of grids and grid computing, such as size, dynamic features, distribution and heterogeneity, are also pushing to the forefront service quality issues. These include performance, reliability and security. Although grid middleware can address some of these issues on a wider scale, it has also become imperative to ensure adequate service provision at local level. Load sharing in clusters can contribute to the provision of a high quality service, by exploiting both static and dynamic information. This paper is concerned with the presentation of a load sharing scheme, that can satisfy grid computing requirements. It follows a proactive, non preemptive and distributed approach. Load information is gathered continuously before it is needed, and a task is allocated to the most appropriate node for execution. Performance and reliability are enhanced by the decentralised nature of the scheme and the symmetric roles of the nodes. In addition, the scheme exhibits transparency characteristics that facilitate integration with the grid.
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Distributed applications are being deployed on ever-increasing scale and with ever-increasing functionality. Due to the accompanying increase in behavioural complexity, self-management abilities, such as self-healing, have become core requirements. A key challenge is the smooth embedding of such functionality into our systems. Natural distributed systems such as ant colonies have evolved highly efficient behaviour. These emergent systems achieve high scalability through the use of low complexity communication strategies and are highly robust through large-scale replication of simple, anonymous entities. Ways to engineer this fundamentally non-deterministic behaviour for use in distributed applications are being explored. An emergent, dynamic, cluster management scheme, which forms part of a hierarchical resource management architecture, is presented. Natural biological systems, which embed self-healing behaviour at several levels, have influenced the architecture. The resulting system is a simple, lightweight and highly robust platform on which cluster-based autonomic applications can be deployed.
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Background: Personal health records were implemented with adults with learning disabilities (AWLD) to try to improve their health-care. Materials and Method: Forty GP practices were randomized to the Personal Health Profile (PHP) implementation or control group. Two hundred and one AWLD were interviewed at baseline and 163 followed up after 12 months intervention (PHP group). AWLD and carers of AWLD were employed as research interviewers. AWLD were full research participants. Results: Annual consultation rates in the intervention and control groups at baseline were low (2.3 and 2.6 visits respectively). A slightly greater increase occurred over the year in the intervention group 0.6 ()0.4 to 1.6) visits ⁄ year compared with controls. AWLD in PHP group reported more health problems at follow-up 0.9 (0.0 to 1.8). AWLD liked their PHP (92%) but only 63% AWLD and 55% carers reported PHP usage. Carers had high turnover (34%). Conclusions: No significant outcomes were achieved by the intervention.
Resumo:
The Channel Catchments Cluster (3C) aims to capitalise on outputs from some of the recent projects funded through the INTERREG IVa France (Channel) England programme. The river catchment basins draining into the Channel region drain an area of 137,000km2 and support a human population of over 19M. Throughout history, these catchments, rivers and estuaries have been centres of habitation, developed through commerce and industry, providing transport links to hinterland areas. These catchments also provide drinking water and food through provision of agriculture, fisheries and aquaculture. In addition, many parts of the region are also economically important now for the tourism and leisure industries. Consequently, there is a need to manage the balance of these many and varied human activities within the catchments, rivers, estuaries and marine areas to ensure that they are maintained or restored to good environmental condition . This document highlights some of the recent work carried out by projects within the INTERREG IVa programme that provide tools and techniques to assist in the achievement of these goals.
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Although the narrow stretch of water that separates England from France has seen both welcome (and occasionally less welcome) exchanges during the past thousand years, this physical challenge to the movement of people has certainly served to obstruct collaborative efforts that might establish a more sustainable economy in our part of Europe. Since 2009, the European Regional Development Fund (ERDF)-supported Interreg Programme France (Channel) England Region has actively supported efforts by organisations in France and England to work ever more closely together, to share good practice and to devise new ways to support sustainable development in the Region. The initiatives are certainly rooted in excellent research, but they have also been driven by the real needs of the Region and in all cases partners have worked to develop practical tools that can be readily applied in both France and England. The Channel Catchment Cluster (3C) builds on this growing tradition of cross-border cooperation to bring together the very best new knowledge from recent Anglo-French teamwork. The contents of this Compendium are the result of a wide variety of grass-roots initiatives that have benefitted enormously from a cross-border meeting of minds. The Cluster has brought together several of these cross-border teams to discuss their work and to share good practice in the dissemination and application of novel tools for environmental protection. This Compendium therefore not only presents a 'snapshot' of the wide variety of environmental protection and management tools that have emerged from the France (Channel) England Region, it also summarises where they stand on their 'pathway to impact'. There is clearly much more that can be achieved by future cross-border efforts in our Region, but I believe that this Compendium provides an excellent basis for future action. Professor Huw Taylor University of Brighton UK