5,709 research outputs found

    The Rise of Presidential Power Before World War II

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    Converting a SSURGO Soils Database into a Simple Soils Database for Use in Portable Computer and Web-Based GIS Applications

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    The SSURGO soils survey is a very useful tool for people in need of soils information. However, the SSURGO soils database is too large and complex for practical use in a geographic information system (GIS). A simplified version of the database was developed and combined with an array of other landscape data to make county based GIS products that are utilized by both portable computer and web-based applications. This allows for wider distribution of the soils information and the ability to take the data to the field

    A compositional account of motifs, mechanisms, and dynamics in biochemical regulatory networks

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    Regulatory networks depict promoting or inhibiting interactions between molecules in a biochemical system. We introduce a category-theoretic formalism for regulatory networks, using signed graphs to model the networks and signed functors to describe occurrences of one network in another, especially occurrences of network motifs. With this foundation, we establish functorial mappings between regulatory networks and other mathematical models in biochemistry. We construct a functor from reaction networks, modeled as Petri nets with signed links, to regulatory networks, enabling us to precisely define when a reaction network could be a physical mechanism underlying a regulatory network. Turning to quantitative models, we associate a regulatory network with a Lotka-Volterra system of differential equations, defining a functor from the category of signed graphs to a category of parameterized dynamical systems. We extend this result from closed to open systems, demonstrating that Lotka-Volterra dynamics respects not only inclusions and collapsings of regulatory networks, but also the process of building up complex regulatory networks by gluing together simpler pieces. Formally, we use the theory of structured cospans to produce a lax double functor from the double category of open signed graphs to that of open parameterized dynamical systems. Throughout the paper, we ground the categorical formalism in examples inspired by systems biology.Comment: 33 pages. Added several examples, plus minor revision

    Errors of Measurement for Blood Parameters and Physiological and Performance Measures After the Decay of Short-Term Heat Acclimation

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    Introduction: It is important to determine the accuracy of measurements relative to potential treatment effects, with time intervals between tests. Purpose: The aim of this study was to assess the error of measurement for blood parameters, physiological, and performance measures after the decay of short-term heat acclimation. Methods: Ten trained males (Mean±SD: age 28±7 y; body mass 74.6±4.4 kg; 4.26±0.37 L.min-1; peak power output (PPO) 329±42 W) completed an exercising heat stress test (HST) at baseline, 2nd day after acclimation and then during decay at 1, 2, 3 and 5-6 wks. CoV (95% CI), SE (95% CI) and Pearsons (r) were used for analysis of blood volume (blood, plasma, red cell volume, mean hemoglogin mass); plasma (aldosterone, arginine vasopressin [AVP], total protein, albumin, sodium); physiological (rectal temperature, cardiac frequency) and performance (exercise performance capacity, PPO). Results: The CoV (95% CI), SE (95% CI) and r with a 1-wk interval for blood volume was 2.3% (1.6 to 4.3; 1.9 [1.3 to 3.4 mL.Kg-1]; r=0.93; n=10). After 2-wk and 5-6 wks this had increased to 4.9% (3.4 to 9.3; 3.8 [2.6 to 7.0 mL.Kg-1]; r=0.76; n=9) and 5.5% (3.6 to 12.8; 4.5 [2.9 to 10.0 mL.Kg-1]; r=0.65; n=7) respectively. Conclusions: Blood volume and physiological measures demonstrated the least error one week apart but increased thereafter. Plasma concentrations and performance markers had the greatest error with repeat measures after one week. Therefore, for greater reliability and low measurement error measures should be taken no more than one week a part in repeated experimentation

    Errors of measurement for blood parameters, physiological and performance measures after the decay of short-term heat acclimation

    Get PDF
    Introduction: It is important to determine the accuracy of measurements relative to potential treatment effects, with time intervals between tests. Purpose: The aim of this study was to assess the error of measurement for blood parameters, physiological, and performance measures after the decay of short-term heat acclimation. Methods: Ten trained males (Mean±SD: age 28±7 y; body mass 74.6±4.4 kg; 4.26±0.37 L.min-1; peak power output (PPO) 329±42 W) completed an exercising heat stress test (HST) at baseline, 2nd day after acclimation and then during decay at 1, 2, 3 and 5-6 wks. CoV (95% CI), SE (95% CI) and Pearsons (r) were used for analysis of blood volume (blood, plasma, red cell volume, mean hemoglogin mass); plasma (aldosterone, arginine vasopressin [AVP], total protein, albumin, sodium); physiological (rectal temperature, cardiac frequency) and performance (exercise performance capacity, PPO). Results: The CoV (95% CI), SE (95% CI) and r with a 1-wk interval for blood volume was 2.3% (1.6 to 4.3; 1.9 [1.3 to 3.4 mL.Kg-1]; r=0.93; n=10). After 2-wk and 5-6 wks this had increased to 4.9% (3.4 to 9.3; 3.8 [2.6 to 7.0 mL.Kg-1]; r=0.76; n=9) and 5.5% (3.6 to 12.8; 4.5 [2.9 to 10.0 mL.Kg-1]; r=0.65; n=7) respectively. Conclusions: Blood volume and physiological measures demonstrated the least error one week apart but increased thereafter. Plasma concentrations and performance markers had the greatest error with repeat measures after one week. Therefore, for greater reliability and low measurement error measures should be taken no more than one week a part in repeated experimentation

    Simple Basic and Convex Processing Time and Power Models for Common Subtractive Manufacturing Processes

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    This technical report provides formulations of processing time and power requirement models for several common subtractive manufacturing operations, including milling, turning, facing, boring, drilling, reaming, tapping, threading, grinding, and polishing processes. Basic formulations are given using a consistent set of variables and units, as well as convex model formulations for each (if different from the basic formulation). When convex models are given, proof of convexity is provided or discussed. The purpose of these models is to provide a set of potential objective functions for various types of optimization problems in manufacturing and materials processing.Ope

    X-ray Orbital Modulations in Intermediate Polars

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    We present an analysis of 30 archival ASCA and RXTE X-ray observations of 16 intermediate polars to investigate the nature of their orbital modulation. We show that X-ray orbital modulation is widespread amongst these systems, but not ubiquitous as indicated by previous studies that included fewer objects. Only seven of the sixteen systems show a clearly statistically significant modulation depth whose amplitude decreases with increasing X-ray energy. Interpreting this as due to photoelectric absorption in material at the edge of an accretion disc would imply that such modulations are visible for all system inclination angles in excess of 60 degrees. However, it is also apparent that the presence of an X-ray orbital modulation can appear and disappear on a timescale of ~years or months in an individual system. This may be evidence for the presence of a precessing, tilted accretion disc, as inferred in some low mass X-ray binaries.Comment: Accepted for publication in Astronomy & Astrophysics. 9 pages of text, plus 5 pages of tables, plus 33 pages of figure

    Material Units, Structures/Landforms, and Stratigraphy for the Global Geologic Map of Ganymede (1:15M)

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    In the coming year a global geological map of Ganymede will be completed that represents the most recent understanding of the satellite on the basis of Galileo mission results. This contribution builds on important previous accomplishments in the study of Ganymede utilizing Voyager data and incorporates the many new discoveries that were brought about by examination of Galileo data. Material units have been defined, structural landforms have been identified, and an approximate stratigraphy has been determined utilizing a global mosaic of the surface with a nominal resolution of 1 km/pixel assembled by the USGS. This mosaic incorporates the best available Voyager and Galileo regional coverage and high resolution imagery (100-200 m/pixel) of characteristic features and terrain types obtained by the Galileo spacecraft. This map has given us a more complete understanding of: 1) the major geological processes operating on Ganymede, 2) the characteristics of the geological units making up its surface, 3) the stratigraphic relationships of geological units and structures, and 4) the geological history inferred from these relationships. A summary of these efforts is provided here

    Dynamic changes in cellular infiltrates with repeated cutaneous vaccination: a histologic and immunophenotypic analysis

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    <p>Abstract</p> <p>Background</p> <p>Melanoma vaccines have not been optimized. Adjuvants are added to activate dendritic cells (DCs) and to induce a favourable immunologic milieu, however, little is known about their cellular and molecular effects in human skin. We hypothesized that a vaccine in incomplete Freund's adjuvant (IFA) would increase dermal Th1 and Tc1-lymphocytes and mature DCs, but that repeated vaccination may increase regulatory cells.</p> <p>Methods</p> <p>During and after 6 weekly immunizations with a multipeptide vaccine, immunization sites were biopsied at weeks 0, 1, 3, 7, or 12. In 36 participants, we enumerated DCs and lymphocyte subsets by immunohistochemistry and characterized their location within skin compartments.</p> <p>Results</p> <p>Mature DCs aggregated with lymphocytes around superficial vessels, however, immature DCs were randomly distributed. Over time, there was no change in mature DCs. Increases in T and B-cells were noted. Th2 cells outnumbered Th1 lymphocytes after 1 vaccine 6.6:1. Eosinophils and FoxP3<sup>+ </sup>cells accumulated, especially after 3 vaccinations, the former cell population most abundantly in deeper layers.</p> <p>Conclusions</p> <p>A multipeptide/IFA vaccine may induce a Th2-dominant microenvironment, which is reversed with repeat vaccination. However, repeat vaccination may increase FoxP3<sup>+</sup>T-cells and eosinophils. These data suggest multiple opportunities to optimize vaccine regimens and potential endpoints for monitoring the effects of new adjuvants.</p> <p>Trail Registration</p> <p>ClinicalTrials.gov Identifier: NCT00705640</p
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