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Selected AbstractsEfficient communication using message prediction for clusters of multiprocessorsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 10 2002Ahmad Afsahi Abstract With the increasing uniprocessor and symmetric multiprocessor computational power available today, interprocessor communication has become an important factor that limits the performance of clusters of workstations/multiprocessors. Many factors including communication hardware overhead, communication software overhead, and the user environment overhead (multithreading, multiuser) affect the performance of the communication subsystems in such systems. A significant portion of the software communication overhead belongs to a number of message copying operations. Ideally, it is desirable to have a true zero-copy protocol where the message is moved directly from the send buffer in its user space to the receive buffer in the destination without any intermediate buffering. However, due to the fact that message-passing applications at the send side do not know the final receive buffer addresses, early arrival messages have to be buffered at a temporary area. In this paper, we show that there is a message reception communication locality in message-passing applications. We have utilized this communication locality and devised different message predictors at the receiver sides of communications. In essence, these message predictors can be efficiently used to drain the network and cache the incoming messages even if the corresponding receive calls have not yet been posted. The performance of these predictors, in terms of hit ratio, on some parallel applications are quite promising and suggest that prediction has the potential to eliminate most of the remaining message copies. We also show that the proposed predictors do not have sensitivity to the starting message reception call, and that they perform better than (or at least equal to) our previously proposed predictors. Copyright © 2002 John Wiley & Sons, Ltd. [source] Linkage disequilibrium estimates of contemporary Ne using highly variable genetic markers: a largely untapped resource for applied conservation and evolutionEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 3 2010Robin S. Waples Abstract Genetic methods are routinely used to estimate contemporary effective population size (Ne) in natural populations, but the vast majority of applications have used only the temporal (two-sample) method. We use simulated data to evaluate how highly polymorphic molecular markers affect precision and bias in the single-sample method based on linkage disequilibrium (LD). Results of this study are as follows: (1) Low-frequency alleles upwardly bias , but a simple rule can reduce bias to Fuel Cell Vehicle Simulation , Part 1: Benchmarking Available Fuel Cell Vehicle Simulation ToolsFUEL CELLS, Issue 3 2003K.H. Hauer Abstract Fuel cell vehicle simulation is one method for systematic and fast investigation of the different vehicle options (fuel choice, hybridization, reformer technologies). However, a sufficient modeling program, capable of modeling the different design options, is not available today. Modern simulation programs should be capable of serving as tools for analysis as well as development. Shortfalls of the existing programs, initially developed for internal combustion engine hybrid vehicles, are: (i)Insufficient modeling of transient characteristics; (ii) Insufficient modeling of the fuel cells system; (iii) Insufficient modeling of advanced hybrid systems; (iv) Employment of a non-causal (backwards looking) structure; (v) Significant shortcomings in the area of controls. In the area of analysis, a modeling tool for fuel cell vehicles needs to address the transient dynamic interaction between the electric drive train and the fuel cell system. Especially for vehicles with slow responding on-board fuel processor, this interaction is very different from the interaction between a battery (as power source) and an electric drive train in an electric vehicle design. Non-transient modeling leads to inaccurate predictions of vehicle performance and fuel consumption. When applied in the area of development, the existing programs do not support the employment of newer techniques, such as rapid prototyping. This is because the program structure merges control algorithms and component models, or different control algorithms (from different components) are lumped together in one single control block and not assigned to individual components as they are in real vehicles. In both cases, the transfer of control algorithms from the model into existing hardware is not possible. This paper is the first part of a three part series and benchmarks the "state of the art" of existing programs. The second paper introduces a new simulation program, which tries to overcome existing barriers. Specifically it explicitly recognizes the dynamic interaction between fuel cell system, drive train and optional additional energy storage. [source] Men at Work and at Home: Managing Emotion in TeleworkGENDER, WORK & ORGANISATION, Issue 1 2008Katy Marsh Home-based telework, as one of the flexible working options available today, is unique in its ability to blur physically and emotionally the boundaries between work and home. This article explores how men experience working from home, how they construct their identities as workers and as parents in this ambiguous location and how, as fathers, they manage the emotional work of reconciling family and career in this context. Our findings suggest that in order to manage the emotional aspects of telework men will, at times, focus on either the professional or parental part of their identity in their narratives, and at times attempt to ,have it all'. We conclude that telework can provide a space where men can adopt emotional discourses and practices traditionally associated with women and, particularly, with working mothers. [source] High-confidence control: Ensuring reliability in high-performance real-time systemsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 4 2004Tariq Samad Technology transfer is an especially difficult proposition for real-time control. To facilitate it, we need to complement the "high-performance" orientation of control research with an emphasis on establishing "high confidence" in real-time implementation. Two particular problems are discussed and recent research directed at their solutions is presented. First, the use of anytime algorithms requires dynamic resource management technology that generally is not available today in real-time systems. Second, complex algorithms have unpredictable computational characteristics that, nevertheless, need to be modeled; statistical verification is suggested as a possible approach. In both cases, a synthesis of control engineering and computer science is required if effective solutions are to be devised. Simulation-based demonstrations with uninhabited aerial vehicles (UAVs) serve to illustrate the research efforts. © 2004 Wiley Periodicals, Inc. [source] The Global Health Situation in the 21st Century: Aspects from the Global Forum on Health Research and the World Health Organization in Geneva,INTERNATIONAL REVIEW OF MISSION, Issue 376-377 2006Louis J. Currat The objective of this paper is, in a first part, to give an overview of the main health problems in the world today and of their main causes. Then an attempt is made to compare the financial and human resourced available today to solve these problems with the resources which would be needed if we are to achieve the Health Millennium Development Goals by 2015. Given the fact that the available resources are limited, the question is then raised as to the selection of the strategies which would contribute the most to an improvement of the health situation in the world. To conclude on a positive note, a few examples are then given of great achievements in the health field over the past 50 years, but attention is drawn to the tremendous challenges remaining if the health MDGs are to be reached by 2015, particularly in Africa. [source] The epidemiologic, health-related quality of life, and economic burden of gastrointestinal stromal tumoursJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 6 2007P. Reddy PharmD Summary Background and objectives:, Gastrointestinal stromal tumours (GIST) are uncommon tumours believed to arise from interstitial cells of Cajal or their precursors in the gastrointestinal (GI) tract, accounting for a small percentage of GI neoplasms and sarcomas. Given the recent recognition of GIST as a distinct cancer, as well as new treatment options available today, a review of the epidemiologic, health-related quality of life (HRQL), and economic burden of GIST is timely from a payer, provider and patient perspective and may provide guidance for treatment decision making and reimbursement. Methods:, A systematic literature review of PubMed and five scientific meeting databases, was conducted to identify published studies and abstracts describing the epidemiologic, HRQL and economic impact of GIST. Publications deemed worthy of further review, based on the information available in the abstract, were retrieved in full text. Results and discussion:, Thirty-four publications met the review criteria: 29 provided data on GIST epidemiology, one provided cost data, three reported HRQL outcomes, and one reported cost and HRQL outcomes. The annual incidence of GIST (cases per million) ranged from 6·8 in the USA to 14·5 in Sweden, with an estimated 5-year survival rate of 45,64%. On the Functional Illness of Chronic Therapy-fatigue instrument, GIST patients scored 40·0 compared with 37·6 in anaemic cancer patients (0 = worst; 52 = least fatigue). Total costs over 10 years for managing GIST patients with molecularly targeted treatment was estimated at £47 521,£56 146 per patient compared with £4047,£4230 per patient with best supportive care. Conclusions:, The incidence of GIST appears to be similar by country; the lower estimate in one country could be explained by differences in method of case ascertainment. Data suggest that the HRQL burden of GIST is similar to that with other cancers although this requires further exploration. The value of new therapies in GIST needs to consider not only cost but also anticipated benefits and the unmet medical need in this condition. [source] The thioredoxin system,From science to clinicMEDICINAL RESEARCH REVIEWS, Issue 1 2004Stephan Gromer Abstract The thioredoxin system,formed by thioredoxin reductase and its characteristic substrate thioredoxin,is an important constituent of the intracellular redox milieu. Interactions with many different metabolic pathways such as DNA-synthesis, selenium metabolism, and the antioxidative network as well as significant species differences render this system an attractive target for chemotherapeutic approaches in many fields of medicine,ranging from infectious diseases to cancer therapy. In this review we will present and evaluate the preclinical and clinical results available today. Current trends in drug development are emphasized. © 2003 Wiley Periodicals, Inc. Med Res Rev, 24, No. 1, 40,89, 2004 [source] Probing the dark ages with redshift distribution of gamma-ray burstsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2002T. Roy Choudhury Abstract In this article, we explore the possibility of using the properties of gamma-ray bursts (GRBs) to probe the physical conditions in the epochs prior to reionization. The redshift distribution of GRBs is modelled using the Press,Schechter formalism with an assumption that they follow the cosmic star formation history. We reproduce the observed star formation rate obtained from galaxies in the redshift range 0 < z < 5, as well as the redshift distribution of the GRBs inferred from the luminosity,variability correlation of the burst light curve. We show that the fraction of GRBs at high redshifts, the afterglows of which cannot be observed in the R and I bands owing to H i Gunn,Peterson optical depth can, at the most, account for one third of the dark GRBs. The observed redshift distribution of GRBs, with much less scatter than the one available today, can put stringent constraints on the epoch of reionization and the nature of gas cooling in the epochs prior to reionization. [source] Azathioprine metabolite measurements: Its use in current clinical practicePEDIATRIC TRANSPLANTATION, Issue 6 2004Carolina Rumbo Abstract:, Azathioprine (AZA) is one of the oldest immunosuppressive agents available today. It is used as an immunomodulator in different disciplines such as hematology, dermatology, rheumatology, gastroenterology, and transplant. The present article presents a summary of AZA metabolism and the role of AZA metabolite measurements in the current clinical practice. [source] Adenoviral vectors for gene transfer and therapyTHE JOURNAL OF GENE MEDICINE, Issue S1 2004Christoph Volpers Abstract Due to the very efficient nuclear entry mechanism of adenovirus and its low pathogenicity for humans, adenovirus-based vectors have become gene delivery vehicles that are widely used for transduction of different cell types, especially for quiescent, differentiated cells, in basic research, in gene therapy applications, and in vaccine development. As an important basis for their use as gene medicine, adenoviral vectors can be produced in high titers, they can transduce cells in vivo with transgenes of more than 30 kb, and they do not integrate into the host cell genome. Recent advances in the development of adenoviral vectors have brought considerable progress on issues like target cell specificity and tropism modification, long-term expression of the transgene, as well as immunogenicity and toxicity in vivo, and have suggested that the different generations of non-replicative and replicative vectors available today will each suit best for certain applications. Copyright © 2004 John Wiley & Sons, Ltd. [source]
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