71 research outputs found

    Cost-Effectiveness of Alternative Blood-Screening Strategies for West Nile Virus in the United States

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    BACKGROUND: West Nile virus (WNV) is endemic in the US, varying seasonally and by geographic region. WNV can be transmitted by blood transfusion, and mandatory screening of blood for WNV was recently introduced throughout the US. Guidelines for selecting cost-effective strategies for screening blood for WNV do not exist. METHODS AND FINDINGS: We conducted a cost-effectiveness analysis for screening blood for WNV using a computer-based mathematical model, and using data from prospective studies, retrospective studies, and published literature. For three geographic areas with varying WNV-transmission intensity and length of transmission season, the model was used to estimate lifetime costs, quality-adjusted life expectancy, and incremental cost-effectiveness ratios associated with alternative screening strategies in a target population of blood-transfusion recipients. We compared the status quo (baseline screening using a donor questionnaire) to several strategies which differed by nucleic acid testing of either pooled or individual samples, universal versus targeted screening of donations designated for immunocompromised patients, and seasonal versus year-long screening. In low-transmission areas with short WNV seasons, screening by questionnaire alone was the most cost-effective strategy. In areas with high levels of WNV transmission, seasonal screening of individual samples and restricting screening to blood donations designated for immunocompromised recipients was the most cost-effective strategy. Seasonal screening of the entire recipient pool added minimal clinical benefit, with incremental cost-effectiveness ratios exceeding US$1.7 million per quality-adjusted life-year gained. Year-round screening offered no additional benefit compared to seasonal screening in any of the transmission settings. CONCLUSIONS: In areas with high levels of WNV transmission, seasonal screening of individual samples and restricting screening to blood donations designated for immunocompromised recipients is cost saving. In areas with low levels of infection, a status-quo strategy using a standard questionnaire is cost-effective

    Разработка имитационной модели системы управления горизонтальным сепаратором установки подготовки нефти

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    Объектом исследования является система управления горизонтальным сепаратором установки подготовки нефти. Цель работы: создание имитационной модели системы управления горизонтальным сепаратором. Данная работа направлена на исследование методов настройки ПИД-регулятора системы управления горизонтальным сепаратором установки нефти. Проведен сравнительный анализ полученных результатов моделирования в ППП Matlab для определения наиболее эффективного метода настройки. Разработана имитационная модель системы в пакете Unisim Design.The object of study is a horizontal separator control system for an oil treatment unit. Purpose of work: creating a simulation model of a horizontal separator control system. This work is aimed at the study of tuning methods for the PID controller of the horizontal separator control system of an oil installation. A comparative analysis of the obtained simulation results in the Matlab software was carried out to determine the most effective tuning method. A simulation model of the system in the Unisim Design package has been developed

    Персональная система управления вниманием в интеллектуальных видах деятельности

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    В данной работе описывается процесс разработки персональной системы управления вниманием в интеллектуальных видах деятельности. Объектом исследования является концентрация внимания, а также способы её улучшения реализуемые посредством объекта промышленного дизайна.This paper describes the process of developing a personal attention management system in intellectual activities. The object of research is the concentration of attention, as well as ways to improve it, implemented through the object of industrial design

    Virtual Reality and 3D Imaging to Support Collaborative Decision Making for Adaptation of Long-Life Assets

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    European companies of today are involved in many stages of the product life cycle. There is a trend towards the view of their business as a complex industrial product-service system (IPSS). This trend shifts the business focus from a traditional product oriented one to a function oriented one. With the function in focus, the seller shares the responsibility of for example maintenance of the product with the buyer. As such IPSS has been praised for supporting sustainable practices. This shift in focus also promotes longevity of products and promotes life extending work on the products such as adaptation and upgrades. Staying competitive requires continuous improvement of manufacturing and services to make them more flexible and adaptive to external changes. The adaptation itself needs to be performed efficiently without disrupting ongoing operations and needs to result in an acceptable after state. Virtual planning models are a key technology to enable planning and design of the future operations in parallel with ongoing operations. This chapter presents an approach to combine digitalization and virtual reality (VR) technologies to create the next generation of virtual planning environments. Through incorporating digitalization techniques such as 3D imaging, the models will reach a new level of fidelity and realism which in turn makes them accessible to a broader group of users and stakeholders. Increased accessibility facilitates a collaborative decision making process that invites and includes cross functional teams. Through such involvement, a broader range of experts, their skills, operational and tacit knowledge can be leveraged towards better planning of the upgrade process. This promises to shorte

    Transfusion-transmitted infections

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    Although the risk of transfusion-transmitted infections today is lower than ever, the supply of safe blood products remains subject to contamination with known and yet to be identified human pathogens. Only continuous improvement and implementation of donor selection, sensitive screening tests and effective inactivation procedures can ensure the elimination, or at least reduction, of the risk of acquiring transfusion transmitted infections. In addition, ongoing education and up-to-date information regarding infectious agents that are potentially transmitted via blood components is necessary to promote the reporting of adverse events, an important component of transfusion transmitted disease surveillance. Thus, the collaboration of all parties involved in transfusion medicine, including national haemovigilance systems, is crucial for protecting a secure blood product supply from known and emerging blood-borne pathogens

    Genomic Analysis of QTLs and Genes Altering Natural Variation in Stochastic Noise

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    Quantitative genetic analysis has long been used to study how natural variation of genotype can influence an organism's phenotype. While most studies have focused on genetic determinants of phenotypic average, it is rapidly becoming understood that stochastic noise is genetically determined. However, it is not known how many traits display genetic control of stochastic noise nor how broadly these stochastic loci are distributed within the genome. Understanding these questions is critical to our understanding of quantitative traits and how they relate to the underlying causal loci, especially since stochastic noise may be directly influenced by underlying changes in the wiring of regulatory networks. We identified QTLs controlling natural variation in stochastic noise of glucosinolates, plant defense metabolites, as well as QTLs for stochastic noise of related transcripts. These loci included stochastic noise QTLs unique for either transcript or metabolite variation. Validation of these loci showed that genetic polymorphism within the regulatory network alters stochastic noise independent of effects on corresponding average levels. We examined this phenomenon more globally, using transcriptomic datasets, and found that the Arabidopsis transcriptome exhibits significant, heritable differences in stochastic noise. Further analysis allowed us to identify QTLs that control genomic stochastic noise. Some genomic QTL were in common with those altering average transcript abundance, while others were unique to stochastic noise. Using a single isogenic population, we confirmed that natural variation at ELF3 alters stochastic noise in the circadian clock and metabolism. Since polymorphisms controlling stochastic noise in genomic phenotypes exist within wild germplasm for naturally selected phenotypes, this suggests that analysis of Arabidopsis evolution should account for genetic control of stochastic variance and average phenotypes. It remains to be determined if natural genetic variation controlling stochasticity is equally distributed across the genomes of other multi-cellular eukaryotes

    High - Tech am Ohr: Der Prozessor ersetzt das Sinnesorgan

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    On-farm measurement of electrical conductivity for the estimation of ammonium nitrogen concentration in pig slurry

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    33 Pags., 6 Figs, 5 Tabls. The definitive version is available at: https://www.crops.org/publications/jeqPig (Sus scrofa domesticus) slurry (PS) is commonly applied as fertilizer to agricultural fields. Knowledge of PS nitrogen content is essential for good management, but PS nitrogen content is highly variable not only between farms but also within a farm. Laboratory analysis of animal slurries is often expensive and impractical for routine farmer use. Therefore, when slurry is spread on land its fertilizer value is generally unknown resulting in risk of pollution. In this work, two rapid and suitable for field use, methods for determining PS ammonium-N (NH4 +-N) concentration (Quantofix® and conductimetry) are evaluated. The electrical conductivity of a dilution 1 PS: 9 distilled water (EC1:9) had better results than Quantofix®, did not need reagents and in addition, gave a direct value of NH4 +-N concentrations (range 1.0 - 7.6 kg NH4 +-N m-3). The conductimetry method allows the use of alternative waters with EC < 1.9 dS m-1 for dilution. The method is being introduced to farmers in northeast Spain in order to improve PS management and has been well received due to its low cost and ease of use in practical application.This study was funded by the National Institute for Agriculture and Food Research and Technology of Spain - INIA (projects SC00-061 and RTA-2010-00126) and with FEDER (European Fund for Regional Development) and FEADER (European Agricultural Fund for Rural Development) funds.Peer reviewe
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