1,938 research outputs found

    Near ground level sensing for spatial analysis of vegetation

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    Measured changes in vegetation indicate the dynamics of ecological processes and can identify the impacts from disturbances. Traditional methods of vegetation analysis tend to be slow because they are labor intensive; as a result, these methods are often confined to small local area measurements. Scientists need new algorithms and instruments that will allow them to efficiently study environmental dynamics across a range of different spatial scales. A new methodology that addresses this problem is presented. This methodology includes the acquisition, processing, and presentation of near ground level image data and its corresponding spatial characteristics. The systematic approach taken encompasses a feature extraction process, a supervised and unsupervised classification process, and a region labeling process yielding spatial information

    The Proficiency Illusion

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    Examines the tests states use to measure academic progress under the No Child Left Behind Act. Explores whether expectations for proficiency in reading and mathematics are consistent between states

    Discussion of Administrative Procedure

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    Walking along sulfation pathways:a personal journey

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    Sulfation pathways are understood as the non-reductive arm of sulfur biology. It is all about the making and breaking of biological sulfate esters. They have been the subject of our research for many years. Putting a negatively charged sulfate group on small molecules, on larger proteins or on humongously large sugar chains changes the chemical properties of these molecules immensely. Hence, sulfation pathways have an impact on biological processes as diverse as detoxification of ingested substances, steroid signalling, protein interaction, bio-mineralization and ageing. Traditionally, there wasn’t a ‘sulfation community’, as the subject was dealt with as a marginal matter at more general biochemical meetings. However, a growing sulfation community has recently been forged. This article showcases the achievements to highlight sulfation pathways in Science–Art (SciArt) projects

    Internationalization, globalization and regionalization: some institutional aspects of systemic transition

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    [Introduction]: ....This paper will argue that the nature and dimensions of ‘globalization’ in the terms used above has its origins in the major changes in economic activity that have characterised the last two hundred years; basically the onset and spread of the industrial mode of production. These changes have given institutional shape to the economic systems which have framed the ways in which the dynamics of trade and technology have worked to establish, integrate and extend markets. That institutional development has been defined in the creation of national and international organizational structures. Economic outcomes, in the sense of economic development and performance measured by growth have been affected by the apparent functional efficiency of those organizational structures and their institutional elements. Those structures and institutions frequently have functions other than the purely economic; they may express cultures and ideologies for instance. Those noneconomic functions have interacted with the economic functions to determine the general and specific outcomes of organizations and institutions. The dominant organizational form evolving over the last two hundred years has been the nation-state both in the administration of its own internal affairs and in the definition of what are termed inter-national relationships. The paper will then argue that the economic pressures of trade and technology which have driven the defining economic elements of the nation state form are in the process of overwhelming that form. That is, through overwhelming the public policy instruments of control over economy and society available to national governments. The paper then speculates on the likely determinants, nature and consequences of successor forms and their institutional aspects. These forms may be multinational, supranational or less obviously a combination in some appropriate institutional form of supra- and sub-national entities

    Criticality for the Gehring link problem

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    In 1974, Gehring posed the problem of minimizing the length of two linked curves separated by unit distance. This constraint can be viewed as a measure of thickness for links, and the ratio of length over thickness as the ropelength. In this paper we refine Gehring's problem to deal with links in a fixed link-homotopy class: we prove ropelength minimizers exist and introduce a theory of ropelength criticality. Our balance criterion is a set of necessary and sufficient conditions for criticality, based on a strengthened, infinite-dimensional version of the Kuhn--Tucker theorem. We use this to prove that every critical link is C^1 with finite total curvature. The balance criterion also allows us to explicitly describe critical configurations (and presumed minimizers) for many links including the Borromean rings. We also exhibit a surprising critical configuration for two clasped ropes: near their tips the curvature is unbounded and a small gap appears between the two components. These examples reveal the depth and richness hidden in Gehring's problem and our natural extension.Comment: This is the version published by Geometry & Topology on 14 November 200

    THE ROLE OF PREDATORS IN THE ECOLOGY, EPIDEMIOLOGY, AND SURVEILLANCE OF PLAGUE IN THE UNITED STATES

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    Predators play important roles in the ecology, epidemiology, and surveillance of plague in the United States. Most predators are accidental hosts of plague and, with the possible exception of grasshopper mice (Onychomys spp.), are not important sources of infection for feeding fleas. However, predators undoubtedly do play an important role in the natural cycle of plague by transporting infected fleas between different populations of plague-susceptible rodents. Predators are known to be at least accidental hosts for 40 of the 50 flea species that have been found to be naturally infected with plague in the U.S. Carnivores, including domestic cats, also play an important epidemiological role and have been sources of infection for 24 human plague cases since 1970. Serosurveillance of rodent-consuming carnivores is currently the most cost-effective method of monitoring plague in the western U.S. During the 1990s, these surveys have allowed CDC and other public health agencies to both identify plague risks for humans living in endemic regions and document the spread of plague into areas where it had not been identified previously

    Surface-to-subsurface stratigraphy of the Caney Shale in portions of Pontotoc, Coal, Pittsburg, and Hughes Counties, Oklahoma, Arkoma basin

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    The Caney Shale is an organic-rich, dark fissile shale of late Mississippian age with localized phosphate and limestone concretions. The Caney Shale in the Arkoma basin of Oklahoma is stratigraphically equivalent to the Barnett Shale of the Fort Worth basin, Texas and partially equivalent to the Fayetteville Shale. The Caney Shale is subdivided into three members; Ahloso, Delaware Creek, and Sand Branch. The Ahloso Member is characterized by its silt content, the Delaware Creek Member is characterized by its loss of silt and addition of carbonate concretions, and the Sand Branch Member is organic-rich, phosphatic, and contains minor carbonate concretions. The three members have distinct wireline log signatures that can be correlated from outcrop into the subsurface and used to map the distributions of each member. In general, all members gradually thin to the northeast and southeast. The Ahloso Member is the thinnest, whereas the Delaware Creek Member and Sand Branch Member are relatively close in thickness. Pay, as defined by total gamma-ray, was determined for the Sand Branch Member and appears to mirror its total thickness

    LINKING LOGAN: Reconnecting the Logan Triangle

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    The purpose of this project is to reinvigorate the Logan Neighborhood through the revitalization and reengagement of the Logan Triangle. Through traditional row housing, multi-family apartment complexes, investments in local businesses with prime retail space; combined with a multi-faceted community center, exceptional amphitheater space, and extensive greenspace, we look to turn Logan Triangle from a blighted oversight into a point of pride for the Logan Neighborhood
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