841 research outputs found

    Implementation of the FAA research and development electromagnetic database

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    The Idaho National Engineering Laboratory (INEL) has been assisting the FAA in developing a database of information about lightning. The FAA Research and Development Electromagnetic Database (FRED) will ultimately contain data from a variety of airborne and ground-based lightning research projects. An outline of the data currently available in FRED is presented. The data sources which the FAA intends to incorporate into FRED are listed. In addition, it describes how the researchers may access and use the FRED menu system

    Learning organisations: A literature review and critique

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    Approved for Public Release - UnclassifiedA literature review on the Learning Organisation field was conducted, examining the dominant assumptions and creating a solid foundation for the practical application of the learning organisation concept to the Australian Army. In order to examine the literature's dominant assumptions, we asked the following questions: (i) What are the various meanings attributed to learning organisations?; (ii) What sorts of learnings are privileged within the literature?; (iii) What are the key characteristics or "building blocks" that make up a learning organisation? We discovered that the learning organisation construct represents an evolution from bureaucratic and performance-based organisational form to innovative and flexible organisations. In surveying the literature, other factors found to impact on learning organisations included cognitive, social, cultural, technological and structural elements. For example, learning organisations apply increasingly sophisticated understanding of knowledge and personnel management to best exploit their social, intellectual and knowledge capital. In contrast, some factors are not adequately explored in the literature; for example, the significance of power relations, hierarchy and authority on learning within and by organisations has not been fully elucidated. There is an increasing number of studies investigating the direct impact of developing a learner-centric approach on organisational outcomes; the number of studies linking learning to improved organisational performance is growing. There are real, significant and measureable benefits of developing the learning capabilities of an organisation.Steven Talbot, Christina Stothard, Maya Drobnjak and Denise McDowal

    Improving functional annotation for industrial microbes: a case study with Pichia pastoris.

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    The research communities studying microbial model organisms, such as Escherichia coli or Saccharomyces cerevisiae, are well served by model organism databases that have extensive functional annotation. However, this is not true of many industrial microbes that are used widely in biotechnology. In this Opinion piece, we use Pichia (Komagataella) pastoris to illustrate the limitations of the available annotation. We consider the resources that can be implemented in the short term both to improve Gene Ontology (GO) annotation coverage based on annotation transfer, and to establish curation pipelines for the literature corpus of this organism.We gratefully acknowledge funding from the Wellcome Trust (PomBase and Canto; WT090548MA to SGO), and the EU 7th Framework Programme (BIOLEDGE Contract No: 289126 to SGO).This is the published version distributed under a Creative Commons Attribution License 2.0, which can also be found on the publisher's website at: http://www.sciencedirect.com/science/article/pii/S0167779914001061

    Distribution and abundance of fish and crayfish in a Waikato stream in relation to basin area

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    The aim of this study was to relate the longitudinal distribution of fish and crayfish to increasing basin area and physical site characteristics in the Mangaotama Stream, Waikato region, North Island, New Zealand. Fish and crayfish were captured with two-pass removal electroshocking at 11 sites located in hill-country with pasture, native forest, and mixed land uses within the 21.6 km2 basin. Number of fish species and lineal biomass of fish increased with increasing basin area, but barriers to upstream fish migration also influenced fish distribution; only climbing and non-migratory species were present above a series of small waterfalls. Fish biomass increased in direct proportion to stream width, suggesting that fish used much of the available channel, and stream width was closely related to basin area. Conversely, the abundance of crayfish was related to the amount of edge habitat, and therefore crayfish did not increase in abundance as basin area increased. Densities of all fish species combined ranged from 17 to 459 fish 100 m-2, and biomass ranged from 14 to 206 g m-2. Eels dominated the fish assemblages, comprising 85-100% of the total biomass; longfinned eels the majority of the biomass at most sites. Despite the open access of the lower sites to introduced brown trout, native species dominated all the fish communities sampled

    The Ames Virtual Environment Workstation: Implementation issues and requirements

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    This presentation describes recent developments in the implementation of a virtual environment workstation in the Aerospace Human Factors Research Division of NASA's Ames Research Center. Introductory discussions are presented on the primary research objectives and applications of the system and on the system's current hardware and software configuration. Principle attention is then focused on unique issues and problems encountered in the workstation's development with emphasis on its ability to meet original design specifications for computational graphics performance and for associated human factors requirements necessary to provide compelling sense of presence and efficient interaction in the virtual environment

    Phylogenetic-based propagation of functional annotations within the Gene Ontology consortium

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    The goal of the Gene Ontology (GO) project is to provide a uniform way to describe the functions of gene products from organisms across all kingdoms of life and thereby enable analysis of genomic data. Protein annotations are either based on experiments or predicted from protein sequences. Since most sequences have not been experimentally characterized, most available annotations need to be based on predictions. To make as accurate inferences as possible, the GO Consortium's Reference Genome Project is using an explicit evolutionary framework to infer annotations of proteins from a broad set of genomes from experimental annotations in a semi-automated manner. Most components in the pipeline, such as selection of sequences, building multiple sequence alignments and phylogenetic trees, retrieving experimental annotations and depositing inferred annotations, are fully automated. However, the most crucial step in our pipeline relies on software-assisted curation by an expert biologist. This curation tool, Phylogenetic Annotation and INference Tool (PAINT) helps curators to infer annotations among members of a protein family. PAINT allows curators to make precise assertions as to when functions were gained and lost during evolution and record the evidence (e.g. experimentally supported GO annotations and phylogenetic information including orthology) for those assertions. In this article, we describe how we use PAINT to infer protein function in a phylogenetic context with emphasis on its strengths, limitations and guidelines. We also discuss specific examples showing how PAINT annotations compare with those generated by other highly used homology-based methods

    Alzheimer\u27s, angiotensin IV and an aminopeptidase

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    The angiotensin AT4 receptor was originally defined as the specific, high affinity binding site for the hexapeptide angiotensin IV (Ang IV). Subsequently, the peptide LVV-hemorphin 7 was also demonstrated to be a bioactive ligand of the AT4 receptor. Central administration of Ang IV or LVV-hemorphin 7 (LVV-H7) markedly enhances learning and memory in normal rodents and reverse memory deficits observed in animal models of amnesia. The high affinity binding site has a broad distribution in the brain including areas such as the hippocmapus that are involved in memory processing. The high affinity Ang IV binding site (AT4 receptor) has been identified as the transmembrane enzyme, insulin-regulated membrane aminopeptidase (IRAP). Insulin-regulated aminopeptidase is a type II integral membrane spanning protein belonging to the M1 family of aminopeptidases and in insulin-responsive cells colocalizes with GLUT4 in specific intra-cellular vesicles. Both Ang IV and LVV-H7 are competitive inhibitors of IRAP catalytic activity and are not substrates of the enzyme.<br /

    Fluctuations and differential contraction during regeneration of Hydra vulgaris tissue toroids

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    We studied regenerating bilayered tissue toroids dissected from Hydra vulgaris polyps and relate our macroscopic observations to the dynamics of force-generating mesoscopic cytoskeletal structures. Tissue fragments undergo a specific toroid-spheroid folding process leading to complete regeneration towards a new organism. The time scale of folding is too fast for biochemical signalling or morphogenetic gradients which forced us to assume purely mechanical self-organization. The initial pattern selection dynamics was studied by embedding toroids into hydro-gels allowing us to observe the deformation modes over longer periods of time. We found increasing mechanical fluctuations which break the toroidal symmetry and discuss the evolution of their power spectra for various gel stiffnesses. Our observations are related to single cell studies which explain the mechanical feasibility of the folding process. In addition, we observed switching of cells from a tissue bound to a migrating state after folding failure as well as in tissue injury. We found a supra-cellular actin ring assembled along the toroid's inner edge. Its contraction can lead to the observed folding dynamics as we could confirm by finite element simulations. This actin ring in the inner cell layer is assembled by myosin- driven length fluctuations of supra-cellular {\alpha}-actin structures (myonemes) in the outer cell-layer.Comment: 19 pages and 8 figures, submitted to New Journal of Physic

    Reliability and validity of cross-national homicide data: A comparison of UN and WHO data

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    Data reliability and validity are major methodological concerns in cross-national analyses of crime. Despite the large literature on cross-national homicide rates, there is little agreement on which source of data provides the most reliable estimates. In addition, few studies have examined the potential threat to validity posed by unclassified deaths. Through a description of trends over time as well as multivariate analyses, the current study aims to shed some light on these questions by (1) assessing the reliability of cross-national homicide data from the United Nations and the World Health Organization, and (2) investigating the impact of unclassified deaths on the validity of WHO data. Findings indicate that UN and WHO homicide rates (n=56) differ in magnitude but produce similar outcomes. Drawing on well-known correlates of cross-national homicide rates, the UN data provide more robust results and produce statistical models with less error. We find that WHO data are more stable and reliable over time, and better suited for longitudinal analyses. Findings also suggest that analyses drawing on WHO homicide data should not disregard unclassified deaths because their inclusion produces better fitted statistical models and provides a closer estimate of the true number of homicides
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