447 research outputs found

    Rurality or distance to care and the risk of homelessness among Afghanistan and Iraq veterans

    Full text link
    INTRODUCTION: To date, no studies have examined the relationship of rurality and distance to nearest VA facility to risk of homelessness. METHODS: We examined differences in the rate of homelessness within a year of a Veteran's first encounter with the VA following last military separation based on rurality and distance to the nearest VA facility using multivariable log-binomial regressions. RESULTS: In our cohort of 708,120 Veterans, 73% were determined to have a forwarding address in urban areas, 59.2% and 86.7% lived within 40 miles of the nearest VA medical center (VAMC), respectively. Veterans living in a rural area and those living between 20+ miles away from the nearest VAMC were at a lower risk for homelessness. CONCLUSIONS: Our unique dataset allowed us to explore the relationship between geography and homelessness. These results are important to policy makers in understanding the risk factors for homelessness among Veterans and planning interventions

    Interaction of graphene-related materials with human intestinal cells: an in vitro approach

    Get PDF
    Graphene-related materials (GRM) inherit unique combinations of physicochemical properties which offer a high potential for technological as well as biomedical applications. It is not clear which physicochemical properties are the most relevant factors influencing the behavior of GRM in complex biological environments. In this study we have focused on the interaction of GRM, especially graphene oxide (GO),and Caco-2 cells in vitro. We mimiked stomach transition by acid-treatment of two representative GRM followed by analysis of their physicochemical properties. No significant changes in the material properties or cell viability of exposed Caco-2 cells in respect to untreated GRM could be detected. Furthermore, we explored the interaction of four different GO and Caco-2 cells to identify relevant physicochemical properties for the establishment of a material property–biological response relationship. Despite close interaction with the cell surface and the formation of reactive oxygen species (ROS), no acute toxicity was found for any of the applied GO (concentration range 0–80 μg ml−1) after 24 h and 48 h exposure. Graphene nanoplatelet aggregates led to low acute toxicity at high concentrations, indicating that aggregation, the number of layers or the C/O ratio have a more pronounced effect on the cell viability than the lateral size alone

    Evaluation of Hexagon Imagery for Regional Mass Balance Study in the Bhutan Himalayas

    Get PDF
    There is much uncertainty regarding the present and future state of Himalayan glaciers, which supply meltwater for river systems vital to more than 1.4 billion people living throughout Asia. Previous assessments of regional glacier mass balance in the Himalayas using various remote sensing and field-based methods give inconsistent results. In this study, declassified Hexagon stereo imagery is processed to generate a digital elevation model (DEM) in the Bhutan Himalayas. Results indicate that the Hexagon imagery database represents a largely untapped resource for understanding decadal scale patterns of mass balance in the region. Future research will utilize the imagery and DEMs to quantify changes in volume and extent of glaciers in the Bhutan Himalayas by comparing the historical imagery to more recent data and calculating changes in ice volume over an approximately 40 year period

    Characterizing the Statistical Properties and Global Distribution of Dansgaard-Oeschger Events

    Get PDF
    Ice core records from Greenland have shown times of rapid warming during the most recent glacial period, called Dansgaard-Oeschger (D-O) events. D-O events are important to our understanding of both past climate systems and modern climate volatility. In this paper, we present new approaches for sta- tistically evaluating the existence of cyclicity in D-O events and the possible lagged correlation between the Greenland and Antarctica temperature records. Speci cally, we consider permutation testing and bootstrapping methodologies for assessing the cyclicity of D-O events and the correlation between the Green- land and Antarctica records. We nd that there is not enough evidence to conclude that D-O events are cyclical; however, the Antarctica record leads the Greenland record by 545 years with a statistically signi cant correlation of 0.455

    Stable Isotope Records from Mount Logan, Eclipse Ice Cores and Nearby Jellybean Lake. Water Cycle of the North Pacific Over 2000 Years and Over Five Vertical Kilometres: Sudden Shifts and Tropical Connections

    Get PDF
    Three ice cores recovered on or near Mount Logan, together with a nearby lake record (Jellybean Lake), cover variously 500 to 30 000 years. This suite of records offers a unique view of the lapse rate in stable isotopes from the lower to upper troposphere. The region is climatologically important, being beside the Cordilleran pinning-point of the Rossby Wave system and the Aleutian Low. Comparison of stable isotope series over the last 2000 years and model simulations suggest sudden and persistent shifts between modern (mixed) and zonal flow regimes of water vapour transport to the Pacific Northwest. The last such shift was in A.D. 1840. Model simulations for modern and “pure” zonal flow suggest that these shifts are consistent regime changes between these flow types, with predominantly zonal flow prior to ca. A.D. 1840 and modern thereafter. The 5.4 and 0.8 km asl records show a shift at A.D. 1840 and another at A.D. 800. It is speculated that the A.D. 1840 regime shift coincided with the end of the Little Ice Age and the A.D. 800 shift with the beginning of the European Medieval Warm Period. The shifts are very abrupt, taking only a few years at most.Trois carottes de glace prélevées à proximité du mont Logan, combinées à une coupe stratigraphique du lac Jellybean, couvrent une période comprise entre 500 et 30 000 ans. Elles renseignent sur les taux de changement de la composition isotopique de la troposphère. La région étudiée est importante au niveau climatologique puisqu’elle est au point de convergence des ondes de Rossby et de la dépression des Aléoutiennes. La comparaison entre la composition isotopique depuis 2000 ans et les résultats des simulations suggère des changements brusques et persistants entre les régimes de transport de vapeur d’eau modernes et zonaux dans le nord-est du Pacifique, où le dernier changement s’est produit en 1840 de notre ère. Les simulations indiquent que les changements de flux correspondent aux changements de régime, avec un flux zonal avant ca 1840 pour passer au type moderne ensuite. Les forages à 5,4 et 0,8 km d’altitude montrent un changement en A.D. 1840 et un autre en l’an 800. On présume que ces changements de régime coïncident respectivement avec la fin du Petit Âge Glaciaire et le début de la période médiévale chaude, ces changements s’étant produits en quelques années seulement

    Self-Reported Delays in Care Do not Predict Increased Mortality in a Cohort of Community-Dwelling Elders

    Get PDF
    Background: Self-reporting of delayed care is a common measure of access to healthcare. The relationship of such reports to worsened health outcomes is often assumed, but few studies have tested this longitudinal connection. Objective: To determine whether self-reports of delayed care predict increased mortality among community-dwelling elderly. Design: 3-year longitudinal retrospective cohort study. Setting: A five county area of North Carolina. Participants: 4,162 randomly sampled individuals age 65 and older. Measurements: The outcome was the proportional hazard ratio (HR) for death stratified by the factor of interest, baseline self-reports of delayed or foregone care. Control variables included predisposing, enabling, and need factors influencing care seeking and/or mortality. Results: Of 3,964 eligible participants reporting, 61% never, 27% once in awhile, and 12% quite often delayed care. 13% of participants died during the study period. Older age, male gender, lower income, less education, lack of supplemental insurance, less social support, more depression, more severe chronic disease, smoking, and worse self-rated health predict increased mortality (pvalues<.0l). Of these, age, lower income, less education, lack of supplemental insurance, less social support, worse self-rated health, and more depression were significantly associated with more self-reported delays in care. In both an unadjusted and fully adjusted survival model, 3-year mortality rates did not differ among cohorts reporting varying degrees of delayed care. Conclusion: Among community dwelling elders, self-reports of delayed care did not predict increased 3-year mortality rates. These results raise questions about self-reporting of delayed or foregone care as a measure of access to the healthcare system.Master of Public Healt
    corecore