87 research outputs found

    What Have We Learned from RHIC?

    Full text link
    In this talk, I present what I believe we have learned from the recent RHIC heavy ion experiments. The goal of these experiments is to make and study matter at very high energy densities, greater than an order of magnitude larger than that of nuclear matter. Have we made such matter? What have we learned about the properties of this matter? What do we hope and expect to learn in the future?Comment: 34 figure

    The James Webb Space Telescope Mission

    Full text link
    Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4m4m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5m6.5m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

    Finishing the euchromatic sequence of the human genome

    Get PDF
    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Understanding Behavioral Antitrust

    Full text link

    Diffusion Tensor Imaging of Normal-Appearing White Matter as Biomarker for Radiation-Induced Late Delayed Cognitive Decline

    No full text
    Purpose: To determine whether early assessment of cerebral white matter degradation can predict late delayed cognitive decline after radiotherapy (RT). Methods and Materials: Ten patients undergoing conformal fractionated brain RT participated in a prospective diffusion tensor magnetic resonance imaging study. Magnetic resonance imaging studies were acquired before RT, at 3 and 6 weeks during RT, and 10, 30, and 78 weeks after starting RT. The diffusivity variables in the parahippocampal cingulum bundle and temporal lobe white matter were computed. A quality-of-life survey and neuro-cognitive function tests were administered before and after RT at the magnetic resonance imaging follow-up visits. Results: In both structures, longitudinal diffusivity (lambda(parallel to)) decreased and perpendicular diffusivity (lambda(perpendicular to)) increased after RT, with early changes correlating to later changes (p 50% of cingula volume receiving >12 Gy had a greater increase in lambda(perpendicular to) at 3 and 6 weeks (p < .05). The post-RT changes in verbal recall scores correlated linearly with the late changes in cingulum lambda(parallel to) (30 weeks, p < .02). Using receiver operating characteristic curves, early cingulum lambda(parallel to) changes predicted for post-RT changes in verbal recall scores (3 and 6 weeks, p < .05). The neurocognitive test scores correlated significantly with the quality-of-life survey results. Conclusions: The correlation between early diffusivity changes in the parahippocampal cingulum and the late decline in verbal recall suggests that diffusion tensor imaging might be useful as a biomarker for predicting late delayed cognitive decline. (C) 2012 Elsevier Inc

    Coal mining is associated with lung cancer risk in Xuanwei, China

    Get PDF
    Background: Xuanwei, China, experiences some of the highest rates of lung cancer in China. While lung cancer risk has been linked to the household use of bituminous coal, no study has comprehensively evaluated the risk of lung cancer associated with the mining of this coal in Xuanwei. In Xuanwei, coal is typically extracted from underground mines, without ventilation, and transported to the surface using carts powered by manpower or electricity. Methods: We evaluated the risk of lung cancer and working as a coal miner, in the absence of diesel exhaust exposure, in a population-based case-control study of 260 male lung cancer cases and 260 age-matched male controls with information on occupational histories. Odds ratios (ORs) and 95% confidence intervals (CIs) for working as a coal miner and years of working as a coal miner were calculated by conditional logistic regression, adjusting for potential confounders, such as smoking and household coal use. Results: We observed an increased risk of lung cancer among coal miners (OR=2.7; 95%CI=1.3-5.6) compared to noncoal miners. Further, a dose-response relationship was observed for the risk of lung cancer and the number of years working as a coal miner (P trend=0.02), with those working as miners for more than 10 years experiencing an almost fourfold increased risk (OR=3.8; 95%CI=1.4-10.3) compared to noncoal miners. Conclusions: These findings suggest that coal mining in Xuanwei may be a risk factor for lung cancer. © 2011 Wiley Periodicals, Inc.link_to_subscribed_fulltex
    corecore