943 resultados para Chunk-based information diffusion


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Urbanization can exert a profound influence on land covers and landscape characteristics. In this study, we characterize the impact of urbanization on land cover and lacustrine landscape and their consequences in a large urban lake watershed, Donghu Lake watershed (the largest urban lake in China), Central China, by using Landsat TM satellite images of three periods of 1987, 1993 and 1999 and ground-based information. We grouped the land covers into six categories: water body, vegetable land, forested land, shrub-grass land, open area and urban land, and calculated patch-related landscape indices to analyze the effects of urbanization on landscape features. We overlaid the land cover maps of the three periods to track the land cover change processes. The results indicated that urban land continuously expanded from 9.1% of the total watershed area in 1987, to 19.4% in 1993, and to 29.6% in 1999. The vegetable land increased from 7.0% in 1987, 11.9% in 1993, to 13.9% in 1999 to sustain the demands of vegetable for increased urban population. Concurrently, continuous reduction of other land cover types occurred between 1987 and 1999: water body decreased from 30.4% to 23.8%, and forested land from 33.6% to 24.3%. We found that the expansion of urban land has at least in part caused a decrease in relatively wild habitats, such as urban forest and lake water area. These alterations had resulted in significant negative environmental consequences, including decline of lakes, deterioration of water and air quality, and loss of biodiversity.

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We report the synthesis and characterization of Zn-doped InN nanorods by metal-organic chemical vapor deposition. Electron microscopy images show that the InN nanorods are single-crystalline structures and vertically well-aligned. Energy-dispersive X-ray spectroscopy analyses suggest that Zn ions are distributed nonhomogenously in InN nanorods. Simulations based on diffusion model show that the doping concentration along the radial direction of InN nanorod is bowl-like from the exterior to the interior, the doping concentration decreases, and Such dopant distribution result in a bimodal EDXS spectrum of Zn across the nanorod. The study of the mechanism of doping effect is useful for the design of InN-based nanometer devices. Also, high-quality Zn-doped InN nanorods will be very attractive as building blocks for nano-optoelectronic devices.'

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随着企业可获取的信息的大量增长,信息的种类和结构也越来越丰富。从传统的关系数据库,到XML文档以及分布于Web上的大量半结构化的信息。如何把各种不同的数据源统一在一个信息集成平台上,使用户能够高效地,透明地操作各类信息,已经成为一个重要的课题。文章提出的基于XML的企业信息集成框架CII,详细讨论了该框架的设计、实现,以及在国家“九五”重点科技攻关项目:石化应用软件典型示范工程及产品开发上的应用。同时针对工业生产企业中实时数据库的大量使用,该文还专门研究了集成实时数据库信息面临的问题,并提出了相应的解决方案。

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本文从企业生产管理信息系统的现状出发,详细分析了现有信息系统在生产计划管理、生产过程跟踪和系统软件结构方面存在的问题。在此基础上,进一步分析了未来企业对制造信息系统的需求及表现形式,并从信息技术角度研究了构件技术在未来企业制造管理信息系统中的作用,建立了构件技术特征与制造信息系统技术特征之间的映射关系,提出了为实现构件化信息系统所要解决的一些技术问题。

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Rapid judgments about the properties and spatial relations of objects are the crux of visually guided interaction with the world. Vision begins, however, with essentially pointwise representations of the scene, such as arrays of pixels or small edge fragments. For adequate time-performance in recognition, manipulation, navigation, and reasoning, the processes that extract meaningful entities from the pointwise representations must exploit parallelism. This report develops a framework for the fast extraction of scene entities, based on a simple, local model of parallel computation.sAn image chunk is a subset of an image that can act as a unit in the course of spatial analysis. A parallel preprocessing stage constructs a variety of simple chunks uniformly over the visual array. On the basis of these chunks, subsequent serial processes locate relevant scene components and assemble detailed descriptions of them rapidly. This thesis defines image chunks that facilitate the most potentially time-consuming operations of spatial analysis---boundary tracing, area coloring, and the selection of locations at which to apply detailed analysis. Fast parallel processes for computing these chunks from images, and chunk-based formulations of indexing, tracing, and coloring, are presented. These processes have been simulated and evaluated on the lisp machine and the connection machine.

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Urquhart, C., Durbin, J. & Spink, S. (2004). Training needs analysis of healthcare library staff, undertaken for South Yorkshire Workforce Development Confederation. Aberystwyth: Department of Information Studies, University of Wales Aberystwyth. Sponsorship: South Yorkshire WDC (NHS)

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In order to widely use Ge and III-V materials instead of Si in advanced CMOS technology, the process and integration of these materials has to be well established so that their high mobility benefit is not swamped by imperfect manufacturing procedures. In this dissertation number of key bottlenecks in realization of Ge devices are investigated; We address the challenge of the formation of low resistivity contacts on n-type Ge, comparing conventional and advanced rapid thermal annealing (RTA) and laser thermal annealing (LTA) techniques respectively. LTA appears to be a feasible approach for realization of low resistivity contacts with an incredibly sharp germanide-substrate interface and contact resistivity in the order of 10 -7 Ω.cm2. Furthermore the influence of RTA and LTA on dopant activation and leakage current suppression in n+/p Ge junction were compared. Providing very high active carrier concentration > 1020 cm-3, LTA resulted in higher leakage current compared to RTA which provided lower carrier concentration ~1019 cm-3. This is an indication of a trade-off between high activation level and junction leakage current. High ION/IOFF ratio ~ 107 was obtained, which to the best of our knowledge is the best reported value for n-type Ge so far. Simulations were carried out to investigate how target sputtering, dose retention, and damage formation is generated in thin-body semiconductors by means of energetic ion impacts and how they are dependent on the target physical material properties. Solid phase epitaxy studies in wide and thin Ge fins confirmed the formation of twin boundary defects and random nucleation growth, like in Si, but here 600 °C annealing temperature was found to be effective to reduce these defects. Finally, a non-destructive doping technique was successfully implemented to dope Ge nanowires, where nanowire resistivity was reduced by 5 orders of magnitude using PH3 based in-diffusion process.

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Gemstone Team IMAC (Integrative Medicine and Cancer)

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Las cooperativas son entidades con una gran presencia económica y social en España, y tienen una gran influencia en la economía rural de las zonas donde están ubicadas. El principal objetivo del presente trabajo es el análisis del uso de las nuevas tecnologías por parte de las cooperativas agroalimentarias, centrándose en las productoras de aceite de oliva para determinar los principales factores que condicionan su comportamiento en la Red. En el presente estudio se analizan sus sitios web y se determina qué tipo de información aporta, tanto datos generales como datos de comercialización. A partir de los resultados obtenidos, se busca la relación que pueda existir entre el tamaño de la cooperativa, su actividad exportadora o la actividad de comercio electrónico con la presencia online, mediante una regresión logística. De esta manera podremos conocer si realmente la implantación de nuevas tecnologías en las cooperativas permite desarrollar una óptima actividad económica.

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Although coordinated patterns of body movement can be used to communicate action intention, they can also be used to deceive. Often known as deceptive movements, these unpredictable patterns of body movement can give a competitive advantage to an attacker when trying to outwit a defender. In this particular study, we immersed novice and expert rugby players in an interactive virtual rugby environment to understand how the dynamics of deceptive body movement influence a defending player’s decisions about how and when to act. When asked to judge final running direction, expert players who were found to tune into prospective tau-based information specified in the dynamics of ‘honest’ movement signals (Centre of Mass), performed significantly better than novices who tuned into the dynamics of ‘deceptive’ movement signals (upper trunk yaw and out-foot placement) (p<.001). These findings were further corroborated in a second experiment where players were able to move as if to intercept or ‘tackle’ the virtual attacker. An analysis of action responses showed that experts waited significantly longer before initiating movement (p<.001). By waiting longer and picking up more information that would inform about future running direction these experts made significantly fewer errors (p<.05). In this paper we not only present a mathematical model that describes how deception in body-based movement is detected, but we also show how perceptual expertise is manifested in action expertise. We conclude that being able to tune into the ‘honest’ information specifying true running action intention gives a strong competitive advantage.

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Decision making is an important element throughout the life-cycle of large-scale projects. Decisions are critical as they have a direct impact upon the success/outcome of a project and are affected by many factors including the certainty and precision of information. In this paper we present an evidential reasoning framework which applies Dempster-Shafer Theory and its variant Dezert-Smarandache Theory to aid decision makers in making decisions where the knowledge available may be imprecise, conflicting and uncertain. This conceptual framework is novel as natural language based information extraction techniques are utilized in the extraction and estimation of beliefs from diverse textual information sources, rather than assuming these estimations as already given. Furthermore we describe an algorithm to define a set of maximal consistent subsets before fusion occurs in the reasoning framework. This is important as inconsistencies between subsets may produce results which are incorrect/adverse in the decision making process. The proposed framework can be applied to problems involving material selection and a Use Case based in the Engineering domain is presented to illustrate the approach. © 2013 Elsevier B.V. All rights reserved.

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Chronic kidney disease (CKD) has become a serious public health problem because of its associated morbidity, premature mortality and attendant healthcare costs. The rising number of persons with CKD is linked with ageing population structure and an increased prevalence of diabetes, hypertension and obesity. There is an inherited risk associated with developing CKD as evidenced by familial clustering and differing prevalence rates across ethnic groups. Earlier studies to determine the inherited risk factors for CKD rarely identified genetic variants that were robustly replicated. However, improvements in genotyping technologies and analytical methods are now helping to identify promising genetic loci aided by international collaboration and multi-consortia efforts. More recently, epigenetic modifications have been proposed to play a role in both the inherited susceptibility to CKD and, importantly, to explain how the environment dynamically interacts with the genome to alter an individual's disease risk. Genome-wide, epigenome-wide and whole transcriptome studies have been performed and optimal approaches for integrative analysis are being developed. This review summarises recent research and the current status of genetic and epigenetic risk factors influencing CKD using population-based information.

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PURPOSE: Men are living longer with prostate cancer. In a two-country study, we investigated the health-related quality of life (HRQoL) of prostate cancer survivors up to 18 years post-diagnosis.

METHODS: Postal questionnaires were administered in 2012 to 6559 prostate cancer (ICD10 C61) survivors 2-18 years post-diagnosis, identified through population-based cancer registries in Ireland. HRQoL was measured using QLQ-C30 and QLQ-PR25. HRQoL, functional and symptom scores were compared by primary treatment(s) using multiple linear regression.

RESULTS: Fifty-four percent responded (n = 3348). After controlling for socio-demographic and clinical factors, global HRQoL varied significantly by primary treatment (p < 0.001); compared to radical prostatectomy (RP), survivors who received androgen deprivation therapy alone (ADT; p < 0.001) or external beam radiotherapy (EBRT) without concurrent ADT (p = 0.001) had significantly lower global HRQoL. The global HRQoL of men who received brachytherapy (p = 0.157), EBRT with concurrent ADT (p = 0.940) or active surveillance/watchful waiting (p = 0.388) was not significantly different from men treated with RP. There were statistically and clinically significant differences in general (fatigue, pain, dyspnoea, appetite loss, constipation, diarrhoea, financial difficulties) and disease-specific symptoms (sexual, urinary, bowel, ADT) by primary treatment. Fatigue and insomnia scores were high for survivors in all treatment groups.

CONCLUSIONS: Prostate cancer survivors' long-term HRQoL varied with primary treatment.

IMPLICATIONS OF CANCER SURVIVORS: Population-based information regarding statistically and clinically significant treatment effects on long-term global HRQoL, symptom burden and functionality should be provided during treatment decision-making. Screening for symptoms and utilising interventions during long-term follow-up may improve survivors' HRQoL.

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In this study, we introduce an original distance definition for graphs, called the Markov-inverse-F measure (MiF). This measure enables the integration of classical graph theory indices with new knowledge pertaining to structural feature extraction from semantic networks. MiF improves the conventional Jaccard and/or Simpson indices, and reconciles both the geodesic information (random walk) and co-occurrence adjustment (degree balance and distribution). We measure the effectiveness of graph-based coefficients through the application of linguistic graph information for a neural activity recorded during conceptual processing in the human brain. Specifically, the MiF distance is computed between each of the nouns used in a previous neural experiment and each of the in-between words in a subgraph derived from the Edinburgh Word Association Thesaurus of English. From the MiF-based information matrix, a machine learning model can accurately obtain a scalar parameter that specifies the degree to which each voxel in (the MRI image of) the brain is activated by each word or each principal component of the intermediate semantic features. Furthermore, correlating the voxel information with the MiF-based principal components, a new computational neurolinguistics model with a network connectivity paradigm is created. This allows two dimensions of context space to be incorporated with both semantic and neural distributional representations.

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As proteínas existentes nas células são produzidas pelo mecanismo de tradução do mRNA, no qual a informação genética contida nos genes é descodificada em cadeias polipeptídicas. O código genético, que define as regras de descodificação do genoma, minimiza os erros de tradução do mRNA, garantindo a síntese de proteínas com elevada fidelidade. Esta é essencial para a estabilidade do proteoma e para a manutenção e funcionamento dos processos celulares. Em condições fisiológicas normais, os erros da tradução do mRNA ocorrem com frequências que variam de 10-3 a 10-5 erros por codão descodificado. Situações que aumentam este erro basal geralmente estão associadas ao envelhecimento, stresse e a doenças; no entanto, em certos organismos o código genético é traduzido naturalmente com elevado erro, indicando que a síntese de proteínas aberrantes pode de algum modo ser vantajosa. A fim de estudar a resposta celular aos erros de tradução do mRNA, construímos leveduras que incorporam serina no proteoma em resposta a um codão de leucina, usando a expressão constitutiva de um tRNASer mutante. Este fenómeno genético artificial provocou uma forte diminuição da esporulação, da viabilidade e da eficiência de mating, afectando imensamente a reprodução sexual da levedura. Observou-se também uma grande heterogeneidade no tamanho e na forma das células e elevada instabilidade genómica, com o aparecimento de populações poliplóides e aneuplóides. No sentido de clarificar as bases celulares e moleculares daqueles fenótipos e compreender melhor a biologia do erro de tradução do mRNA, construímos também células de levedura que inserem serina em resposta a um codão de leucina de modo indutível e controlado. Utilizaram-se perfis de mRNA total e de mRNA associado a polissomas para elucidar a resposta celular ao erro de tradução do mRNA. Observou-se a indução de genes envolvidos na resposta ao stresse geral, stresse oxidativo e na unfolded protein response (UPR). Um aumento significativo de espécies reactivas de oxigénio (ROS) e um forte impacto negativo na capacidade das células pós-mitóticas re-iniciarem o crescimento foram também observados. Este fenótipo de perda de viabilidade celular foi resgatado por scavangers de ROS, indicando que o stresse oxidativo é a principal causa de morte celular causada pelos erros de tradução. Este estudo levanta a hipótese de que o stresse oxidativo e a acumulação de ROS, ao invés do colapso súbito do proteoma, são as principais causas da degeneração celular e das doenças humanas associadas aos erros de tradução do genoma. ABSTRACT: Proteins are synthesized through the mechanism of translation, which uses the genetic code to transform the nucleic acids based information of the genome into the amino acids based information of the proteome. The genetic code evolved in such a manner that translational errors are kept to a minimum and even when they occur their impact is minimized by similar chemical properties of the amino acids. Protein synthesis fidelity is essential for proteome stability and for functional maintenance of cellular processes. Indeed, under normal physiological conditions, mistranslation occurs at frequencies that range from 10-3 to 10-5 errors per codon decoded. Situations where this basal error frequency increases are usually associated to aging and disease. However, there are some organisms where genetic code errors occur naturally at high level, suggesting that mRNA mistranslation can somehow be beneficial. In order to study the cellular response to mRNA mistranslation, we have engineered single codon mistranslation in yeast cells, using constitutive expression of mutant tRNASer genes. These mistranslating strains inserted serines at leucine-CUG sites on a proteome wide scale due to competition between the wild type tRNALeu with the mutant tRNASer. Such mistranslation event decreased yeast sporulation, viability and mating efficiencies sharply and affected sexual reproduction strongly. High heterogeneity in cell size and shape and high instability in the genome were also observed, with the appearance of some polyploid or aneuploid cell populations. To further study the cellular and molecular basis of those phenotypes and the biology of mRNA mistranslation, we have also engineered inducible mRNA misreading in yeast and used total mRNA and polysome associated mRNA profiling to determine whether codon misreading affects gene expression. Induced mistranslation up-regulated genes involved in the general stress response, oxidative stress and in the unfolded protein response (UPR). A significant increase in reactive oxygen species (ROS) and a strong negative impact on the capacity of post-mitotic cells to re-initiate growth in fresh media were also observed. This cell viability phenotype was rescued by scavengers of ROS, indicating that oxidative stress is the main cause of cell death caused by mRNA mistranslation. This study provides strong support for the hypothesis that oxidative stress and ROS accumulation, rather than sudden proteome collapse or major proteome disruption, are the main cause of the cellular degeneration observed in human diseases associated mRNA mistranslation.