147 research outputs found

    Role of Positive Selection in Functional Divergence of Mammalian Neuronal Apoptosis Inhibitor Proteins during Evolution

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    Neuronal apoptosis inhibitor proteins (NAIPs) are members of Nod-like receptor (NLR) protein family. Recent research demostrated that some NAIP genes were strongly associated with both innate immunity and many inflammatory diseases in humans. However, no similar phenomena have been reported in other mammals. Furthermore, some NAIP genes have undergone pseudogenization or have been lost during the evolution of some higher mammals. We therefore aimed to determine if functional divergence had occurred, and if natural selection had played an important role in the evolution of these genes. The results showed that NAIP genes have undergone pseudogenization and functional divergence, driven by positive selection. Positive selection has also influenced NAIP protein structure, resulting in further functional divergence

    Validation of "Care of the Dying Evaluation" in Emergency Medicine (CODE-EM): pilot phase of end-of-life management protocol offered within emergency room (EMPOWER) study.

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    BackgroundAn increasing number of patients who present to emergency departments are at their end-of-life phase and have significant palliative care needs such as in symptom control for pain and dyspnoea. Evaluating quality of care provided is imperative, yet there is no suitable tool validated in the emergency and Asian settings. We aim to examine the face and construct validity, and reliability of a newly developed questionnaire, Care of the Dying Evaluation - Emergency Medicine, for measuring the quality of end-of-life care in an Asian emergency context.MethodsA mixed methods pilot study was conducted. Participants composed of the next-of-kin to thirty dying patients who presented to the emergency departments of three public hospitals in Singapore. Qualitative evaluation, using cognitive "think-aloud" interviews, and quantitative analysis were employed. Percentage agreement and Îș statistic were measured to evaluate temporal stability of the questionnaire. Cronbach's α and item-total correlations were used to assess internal consistency within the constructs. Confirmatory factor analysis was performed for construct validity.ResultsAll participants reported clear understanding of the questionnaire with no ambiguity; a minority felt the questions caused emotional distress (7/30, 23.3%). The questions showed moderate to good test-retest reliability. Internal consistencies within the constructs were good for "ENVIRONMENT" and "CARE", and moderate for "COMMUNICATION". Factor loadings range from 0.40 to 0.99.ConclusionsThe Care of the Dying Evaluation - Emergency Medicine questionnaire may be valid and reliable for use in an Asian emergency setting. Our prospective multicentre study using this evaluation tool may provide more insight on the quality of care rendered to dying patients and identify areas for improvement.Trial registrationClinicalTrials.gov (NCT03906747)

    Modeling, simulation, analysis and control of close formation flight

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    This paper focuses on the aerodynamic characteristics of aircraft close formation flight. The formation model for small unmanned aircraft is studied, and the disturbance of the wake induced velocity generated by the leader aircraft on the tail aircraft is analyzed. It is found that the lead aircraft has a significant effect on the lift and drag of the tail aircraft. It is also demonstrated that the aerodynamic characteristics of the tail plane can be improved when the following plane is in the proper position of the leader in formation flight. Precise position control of the tail plane in general flight operations is achieved under the influence of the tail vortex. Firstly, a model for the wake vortex of the leader was established, and then computational fluid dynamics(CFD) software was used to simulate the two unmanned aerial vehicles (UAVs) to verify the accuracy of the model. A control algorithm was designed to realize the stability of formation flight. Mathematical simulation and validation were performed. The designed control law is able to keep the tail plane in the appropriate position in the formation flight so that the tail plane is subjected to the maximum lift

    Approximation of bivariate copulas by patched bivariate Fréchet copulas

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    Bivariate Fréchet (BF) copulas characterize dependence as a mixture of three simple structures: comonotonicity, independence and countermonotonicity. They are easily interpretable but have limitations when used as approximations to general dependence structures. To improve the approximation property of the BF copulas and keep the advantage of easy interpretation, we develop a new copula approximation scheme by using BF copulas locally and patching the local pieces together. Error bounds and a probabilistic interpretation of this approximation scheme are developed. The new approximation scheme is compared with several existing copula approximations, including shuffle of min, checkmin, checkerboard and Bernstein approximations and exhibits better performance, especially in characterizing the local dependence. The utility of the new approximation scheme in insurance and finance is illustrated in the computation of the rainbow option prices and stop-loss premiums.Bivariate Frechet copulas Patched bivariate Frechet copula Approximation of bivariate copulas Rainbow options

    Ex situ Flora of China

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    The role of living collections-based research and discovery has been a prominent feature throughout the history of evolution and advance of botanical science: such research is the core and soul of the botanical gardens. Currently, there are c. 162 Chinese botanical gardens, harboring c. 20,000 species in China. As an example of initiatives to utilize the garden cultivated flora to address plant diversity conservation and germplasm discovery for sustainable agriculture and the bio-industries, the Ex situ Flora of China project aims to catalog and document this mega-diversity of plants that are cultivated in the Chinese botanical gardens. The concept of Ex situ Flora of China is a complete new formulation of species, based on garden cultivated individuals and populations, to obtain better morphological descriptions, provide multi-purpose applicability and a fundamental data service that will support national bio-strategies and bio-industries. It emphasises integrative information, accurately collected from living collections across different Chinese botanical gardens, on biology, phenology, cultivation requirements and uses of plant resources, which are normally not available from traditional Floras based on herbarium specimens. The ex situ flora should provide better information coverage for taxonomy, biological and introduction and collection data and color photos of stems, leaves, flowers, fruits and seed, as well as useful information of cultivation key points and main use of each plant. In general, the Ex situ Flora of China provides more useful information than the traditional Flora Reipublicae Popularis Sinicae. The project of Ex situ Flora of China is planned to be one of the most important initiatives of the plant diversity research platform for sustainable economic and social development in China. Keywords: Botanical garden, Living collections, Ex situ conservation, Botanical sciences, Cultivated flor
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