62 research outputs found

    Evidences for Rapid Formation and Failure of Pleistocene Lava Dams of the Western Grand Canyon, AZ.

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    Over 200 isolated outcrops of horizontally stratified, basaltic lava flows within the inner gorge of western Grand Canyon indicate that several natural lava dams blocked the flow of the Colorado River during the Pleistocene, resulting in the formation of several lakes within the canyon. The largest lake was 90 m above the high water level of present-day Lake Powell and backed up a distance of over 480 km to Moab, Utah . Although early studies indicated that three or less dams once blocked the inner gorge, work completed in 1994 indicated that at least 13 distinct lava dams may have blocked the Colorado River. Comparison with modern erosion rates of cliff retreat (Niagara Falls) indicate that the 13 dams would have required a minimum of 250,000 years to erode during the Pleistocene. However, geologic features and relationships not previously considered indicate that the dams formed rapidly (hours, days, or months) and failed catastrophically soon after formation. Excess radiogenic argon is contain within many basalts of Grand Canyon. This initial argon invalidates K-Ar model ages which are assumed by many geologists to require an age of more than one million years for the oldest lava dams. We envision that the entire episode of the lava darns can easily be reconciled within a time-frame of less than two thousand years. Our observations and interpretations reveal serious flaws in the current long-age timescale of the Pleistocene Epoch

    Preventing Cardiovascular Disease in Kentucky: Epidemiology, Trends, and Strategies for the Future

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    Cardiovascular disease (CVD) is the leading cause of death in the United States despite dramatic improvements in the treatment of heart disease in recent years. Kentucky leads the nation in the prevalence of several individual risk factors for cardiovascular disease, the prevalence of multiple risk factors, and in cardiovascular mortality. While trends in the prevalence of some of these cardiac risk factors have shown improvement, others have remained unchanged or have worsened. The increased prevalence of obesity and diabetes, especially among young persons, is one of the most worrisome trends. The prevalence of smoking in Kentucky remains high, and has not declined substantially in the past fifteen years. As a consequence of poverty, low educational levels, a high unemployment rate, and often limited access to medical care, select populations in the Appalachian region of the state have among the highest rates of cardiovascular disease in the developed world. In the 2004 Behavioral Risk Factor Surveillance System (BRFSS) report of the Centers for Disease Control and Prevention, Kentucky had met none of the stated objectives related to cardiovascular risk for Healthy Kentuckians 2010. Public health initiatives and interventions directed toward the prevention of CVD in Kentucky must address Kentucky\u27s unique challenges if progress is to be made

    A Vision for Science Gateways: Bridging the Gap and Broadening the Outreach

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    The future for science gateways warrants exploration as we consider the possibilities that extend well beyond science and high performance computing into new interfaces, applications and user communities. In this paper, we look retrospectively at the successes of representative gateways thus far. This serves to highlight existing gaps gateways need to overcome in areas such as accessibility, usability and interoperability, and in the need for broader outreach by drawing insights from technology adoption research. We explore two particularly promising opportunities for gateways - computational social sciences and virtual reality – and make the case for the gateway community to be more intentional in engaging with users to encourage adoption and implementation, especially in the area of educational usage. We conclude with a call for focused attention on legal hurdles in order to realize the full future potential of science gateways. This paper serves as a roadmap for a vision of science gateways in the next ten years

    Long-Range Enhancer Interactions Are Prevalent in Mouse Embryonic Stem Cells and Are Reorganized upon Pluripotent State Transition.

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    Transcriptional enhancers, including super-enhancers (SEs), form physical interactions with promoters to regulate cell-type-specific gene expression. SEs are characterized by high transcription factor occupancy and large domains of active chromatin, and they are commonly assigned to target promoters using computational predictions. How promoter-SE interactions change upon cell state transitions, and whether transcription factors maintain SE interactions, have not been reported. Here, we used promoter-capture Hi-C to identify promoters that interact with SEs in mouse embryonic stem cells (ESCs). We found that SEs form complex, spatial networks in which individual SEs contact multiple promoters, and a rewiring of promoter-SE interactions occurs between pluripotent states. We also show that long-range promoter-SE interactions are more prevalent in ESCs than in epiblast stem cells (EpiSCs) or Nanog-deficient ESCs. We conclude that SEs form cell-type-specific interaction networks that are partly dependent on core transcription factors, thereby providing insights into the gene regulatory organization of pluripotent cells.P.J.R.-G. is supported by the Wellcome Trust (WT093736), Biotechnology and Biological Sciences Research Council (BB/M022285/1 and BB/P013406/1), and the European Commission Network of Excellence EpiGeneSys (HEALTH-F4-2010-257082). This work was also supported by the following grants to P.F.: Medical Research Council (MR/L007150/1, MC_UP_1302/1, MC_UP_1302/3, MC_UP_1302/5), and Biotechnology and Biological Sciences Research Council (BB/J004480/1)

    A Vision for Science Gateways: Bridging the Gap and Broadening the Outreach

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    The future for science gateways warrants exploration as we consider the possibilities that extend well beyond science and high performance computing into new interfaces, applications and user communities. In this paper, we look retrospectively at the successes of representative gateways thus far. This serves to highlight existing gaps gateways need to overcome in areas such as accessibility, usability and interoperability, and in the need for broader outreach by drawing insights from technology adoption research. We explore two particularly promising opportunities for gateways - computational social sciences and virtual reality – and make the case for the gateway community to be more intentional in engaging with users to encourage adoption and implementation, especially in the area of educational usage. We conclude with a call for focused attention on legal hurdles in order to realize the full future potential of science gateways. This paper serves as a roadmap for a vision of science gateways in the next ten years

    Data Assimilation Enhancements to Air Force Weathers Land Information System

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    The United States Air Force (USAF) has a proud and storied tradition of enabling significant advancements in the area of characterizing and modeling land state information. 557th Weather Wing (557 WW; DoDs Executive Agent for Land Information) provides routine geospatial intelligence information to warfighters, planners, and decision makers at all echelons and services of the U.S. military, government and intelligence community. 557 WW and its predecessors have been home to the DoDs only operational regional and global land data analysis systems since January 1958. As a trusted partner since 2005, Air Force Weather (AFW) has relied on the Hydrological Sciences Laboratory at NASA/GSFC to lead the interagency scientific collaboration known as the Land Information System (LIS). LIS is an advanced software framework for high performance land surface modeling and data assimilation of geospatial intelligence (GEOINT) information

    Author Correction: Promoter interactome of human embryonic stem cell-derived cardiomyocytes connects GWAS regions to cardiac gene networks (Nature Communications, (2018), 9, 1, (2526), 10.1038/s41467-018-04931-0)

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    In the original version of the Article, the gene symbol for tissue factor pathway inhibitor was inadvertently given as ‘TFP1’ instead of ‘TFPI’. This has now been corrected in both the PDF and HTML versions of the Article

    Common risk factor approach to address socioeconomic inequality in the oral health of preschool children – a prospective cohort study

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    Background: Dental caries remains the most prevalent chronic condition in children and a major contributor to poor general health. There is ample evidence of a skewed distribution of oral health, with a small proportion of children in the population bearing the majority of the burden of the disease. This minority group is comprised disproportionately of socioeconomically disadvantaged children. An in-depth longitudinal study is needed to better understand the determinants of child oral health, in order to support effective evidence-based policies and interventions in improving child oral health. The aim of the Study of Mothers’ and Infants’ Life Events Affecting Oral Health (SMILE) project is to identify and evaluate the relative importance and timing of critical factors that shape the oral health of young children and then to seek to evaluate those factors in their inter-relationship with socioeconomic influences.Methods/Design: This investigation will apply an observational prospective study design to a cohort ofsocioeconomically-diverse South Australian newborns and their mothers, intensively following these dyads as the children grow to toddler age. Mothers of newborn children will be invited to participate in the study in the early post-partum period. At enrolment, data will be collected on parental socioeconomic status, mothers’ general and dental health conditions, details of the pregnancy, infant feeding practice and parental health behaviours and practices. Data on diet and feeding practices, oral health behaviours and practices, and dental visiting patterns will be collected at 3, 6, 12 and 24 months of age. When children turn 24-30 months, the children and their mothers/primary care givers will be invited to an oral examination to record oral health status. Anthropometric assessment will also be conducted.Discussion: This prospective cohort study will examine a wide range of determinants influencing child oral health and related general conditions such as overweight. It will lead to the evaluation of the inter-relationship among main influences and their relative effect on child oral health. The study findings will provide high level evidence of pathways through which socio-environmental factors impact child oral health. It will also provide an opportunity to examine the relationship between oral health and childhood overweight.Discussion: This prospective cohort study will examine a wide range of determinants influencing child oral health and related general conditions such as overweight. It will lead to the evaluation of the inter-relationship among main influences and their relative effect on child oral health. The study findings will provide high level evidence of pathways through which socio-environmental factors impact child oral health. It will also provide an to examine the relationship between oral health and childhood overweight

    In vivo MRI signatures of hippocampal subfield pathology in intractable epilepsy.

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    OBJECTIVES: Our aim is to assess the subfield-specific histopathological correlates of hippocampal volume and intensity changes (T1, T2) as well as diff!usion MRI markers in TLE, and investigate the efficacy of quantitative MRI measures in predicting histopathology in vivo. EXPERIMENTAL DESIGN: We correlated in vivo volumetry, T2 signal, quantitative T1 mapping, as well as diffusion MRI parameters with histological features of hippocampal sclerosis in a subfield-specific manner. We made use of on an advanced co-registration pipeline that provided a seamless integration of preoperative 3 T MRI with postoperative histopathological data, on which metrics of cell loss and gliosis were quantitatively assessed in CA1, CA2/3, and CA4/DG. PRINCIPAL OBSERVATIONS: MRI volumes across all subfields were positively correlated with neuronal density and size. Higher T2 intensity related to increased GFAP fraction in CA1, while quantitative T1 and diffusion MRI parameters showed negative correlations with neuronal density in CA4 and DG. Multiple linear regression analysis revealed that in vivo multiparametric MRI can predict neuronal loss in all the analyzed subfields with up to 90% accuracy. CONCLUSION: Our results, based on an accurate co-registration pipeline and a subfield-specific analysis of MRI and histology, demonstrate the potential of MRI volumetry, diffusion, and quantitative T1 as accurate in vivo biomarkers of hippocampal pathology
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