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1.
In eukaryotes, microRNAs (miRNAs) have roles in development, homeostasis, disease and the immune response. Recent work has shown that plant and mammalian miRNAs also mediate cross-kingdom and cross-domain communications. However, these studies remain controversial and are lacking critical mechanistic explanations. Bacteria do not produce miRNAs themselves, and therefore it is unclear how these eukaryotic RNA molecules could function in the bacterial recipient. In this review, we compare and contrast the biogenesis and functions of regulatory RNAs in eukaryotes and bacteria. As a result, we discovered several conserved features and homologous components in these distinct pathways. These findings enabled us to propose novel mechanisms to explain how eukaryotic miRNAs could function in bacteria. Further understanding in this area is necessary to validate the findings of existing studies and could facilitate the use of miRNAs as novel tools for the directed remodelling of the human microbiota.  相似文献   
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Responsiveness is a critical metric for web performance. Recent work in the Internet Engineering Task Force (IETF) and World Wide Web Consortium (W3C) has resulted in a new set of web protocols, including definition of the hypertext transfer protocol version 2 (HTTP/2) and a corresponding set of TCP updates. Together, these have been designed to reduce the web page download latency compared with HTTP/1.1. This paper describes the main features of the new protocols and discusses the impact of path delay on their expected performance. It then presents a set of tests to evaluate whether current implementations of the new protocols can offer benefit with an operational satellite access network and suggests how the specifications can evolve and be tuned to further enhance performance for long network paths. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Increased striatal dopamine D2 receptor activity is thought to contribute to the pathophysiology of schizophrenia. To model this condition in mice, Kellendonk et al. (2006) generated transgenic mice that selectively overexpress the D2 receptor in striatum (D2OE). Drew et al. (2007) reported that D2OE mice display deficits in interval timing and motivation. The present study further explored the impaired timing in D2OE mice. Experiment 1 assessed the role of motivation in producing timing deficits in the peak procedure and found that performance in D2OE mice was improved by increasing motivation. In addition, performance was impaired in control mice when motivation was decreased. In Experiment 2, we found that D2OE mice have no timing impairment when tested using the bisection task, a procedure in which the measure of timing performance is less influenced by motivation to respond. In Experiment 3, we also used the bisection task and found selective impairment in timing of long durations in D2OE mice. These results suggest that striatal D2 overexpression impairs timing by decreasing motivation and through its impact on working memory and/or sustained attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The provision of countryside recreation facilities at a local level is likely to receive increasing attention during the next decade. As an integral part of the assessment of the quality of present provision within the Congleton District of Cheshire (U.K.) five site surveys were made. Each site provides different facilities for recreation and interview questions were designed to investigate the background of the visitors and the nature of the interplay between site and visitor. The analysis of answers attempts to illustrate those aspects of this interrelationship which may be important during the consideration of future provision of recreation sites and their management.  相似文献   
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The provision of countryside recreation facilities at a local level is likely to receive increasing attention during the next decade. As an integral part of the assessment of the quality of present provision within the Congleton District of Cheshire (U.K.) five site surveys were made. Each site provides different facilities for recreation and interview questions were designed to investigate the background of the visitors and the nature of the interplay between site and visitor. The analysis of answers attempts to illustrate those aspects of this interrelationship, which may be important during the consideration of future provision of recreation sites and their management.  相似文献   
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A scheme to generate encryption keys from biometric samples is introduced. The idea is based on partitioning feature space into subspaces and partitioning these into cells. Each cell subspace contributes to the overall key generated. Experimental analysis shows encouraging prospects.  相似文献   
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The performance of memory network pattern classifiers based on a feature frequency-weighting scheme can suffer from an inappropriate arbitrary choice of zero-frequency component in the computation of discriminant functions. This letter assesses the effect of optimising this factor, emphasising the value of optimisation in pairwise class discrimination, which is of particular relevance in the design of efficient hierarchical classifier architectures.  相似文献   
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An analysis of features extracted from handwriting samples according to writer demographics and writing task characteristics is presented. The individual demographics studied here include age, gender and handedness, while the handwriting tasks considered include writing the individual signature, form-filling, cheque-completion and constructing free-form written text. By analysing different features of handwriting, the authors establish a link between a writer's individual characteristics including demographic properties, the handwriting task being attempted and quantifiable features of handwriting such as pen velocity, acceleration and slant. Additionally, imitated or 'forged' handwriting is also analysed on exactly the same basis. The analysis is performed on a newly collected database of handwriting samples collected from a population of 150 writers, and which can be utilised in both forensic document inspection and automatic handwriting analysis research. All handwriting samples, including forgery attempts, were recorded both temporally as a series of pen positional coordinates and scanned at a resolution of 600 dpi to enable both dynamic and static processing.  相似文献   
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