2,378 research outputs found

    The Disdrometer Verification Network (DiVeN): a UK network of laser precipitation instruments

    Get PDF
    Starting in February 2017, a network of 14 Thies laser precipitation monitors (LPMs) were installed at various locations around the United Kingdom to create the Disdrometer Verification Network (DiVeN). The instruments were installed for verification of radar hydrometeor classification algorithms but are valuable for much wider use in the scientific and operational meteorological community. Every Thies LPM is able to designate each observed hydrometeor into one of 20 diameter bins from ≥0.125 to >8 mm and one of 22 speed bins from >0.0 to >20.0 m s−1. Using empirically derived relationships, the instrument classifies precipitation into one of 11 possible hydrometeor classes in the form of a present weather code, with an associated indicator of uncertainty. To provide immediate feedback to data users, the observations are plotted in near-real time (NRT) and made publicly available on a website within 7 min. Here we describe the Disdrometer Verification Network and present specific cases from the first year of observations. Cases shown here suggest that the Thies LPM performs well at identifying transitions between rain and snow, but struggles with detection of graupel and pristine ice crystals (which occur infrequently in the United Kingdom) inherently, due to internal processing. The present weather code quality index is shown to have some skill without the supplementary sensors recommended by the manufacturer. Overall the Thies LPM is a useful tool for detecting hydrometeor type at the surface and DiVeN provides a novel dataset not previously observed for the United Kingdom

    Avoid, Delay, Shorten. Results of Radiation Oncology’s COVID19 Patient Exposure Risk Mitigation Guidelines

    Get PDF
    We implemented evidence-based COVID19 guidelines on 3/16/20 to minimize patient exposure risks by avoiding, delaying, and shortening patient treatments when possible. We analyzed the effectiveness of our COVID guidelines by comparing the number of new patient starts and number of treatments before and after implementation. Our department successfully decreased patient exposure risk by reducing new prescription starts, rates of longer treatment courses, and overall number of treatment encounters in an evidence-based approach

    Fragile charge order in the nonsuperconducting ground state of the underdoped high-temperature superconductors.

    Get PDF
    The normal state in the hole underdoped copper oxide superconductors has proven to be a source of mystery for decades. The measurement of a small Fermi surface by quantum oscillations on suppression of superconductivity by high applied magnetic fields, together with complementary spectroscopic measurements in the hole underdoped copper oxide superconductors, point to a nodal electron pocket from charge order in YBa2Cu3(6+δ). Here, we report quantum oscillation measurements in the closely related stoichiometric material YBa2Cu4O8, which reveals similar Fermi surface properties to YBa2Cu3(6+δ), despite the nonobservation of charge order signatures in the same spectroscopic techniques, such as X-ray diffraction, that revealed signatures of charge order in YBa2Cu3(6+δ). Fermi surface reconstruction in YBa2Cu4O8 is suggested to occur from magnetic field enhancement of charge order that is rendered fragile in zero magnetic fields because of its potential unconventional nature and/or its occurrence as a subsidiary to more robust underlying electronic correlations.B.T., A.S, and S.E.S. acknowledge support from the Royal Society, the Winton Programme for the Physics of Sustainability, and the European Research Council under the European Unions Seventh Framework Programme (grant number FP/2007-2013)/ ERC Grant Agreement number 337425. N.H., Z.Z., F.F.B., and B.J.R. acknowl- edge support for high-magnetic-field experiments from the US Department of Energy, Office of Science, BES- MSE `Science of 100 Tesla' programme. G.G.L. acknowl- edges support from EPSRC grant EP/K012894/1. Work at NIU was supported by The Institute for Nanoscience, Engineering, and Technology - InSET. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by NSF co-operative agreement number DMR-0654118, the state of Florida, and the DOE. We are grateful for the experimental assis- tance provided by National High Magnetic Field Labora- tory personnel, including J. B. Betts, Y. Coulter, M. Gor- don, C. H. Mielke, A. Parish, R. McDonald, D. Rickel, and D. Roybal.This is the author accepted manuscript. The final version is available from the National Academy of Sciences via http://dx.doi.org/10.1073/pnas.150416411

    Postoperative phlegmasia caerulea dolens: a case report and consideration of potential iatrogenic factors

    Get PDF
    While the haemorrhagic consequences of anti-coagulants are well and frequently described in the surgical literature, the paradoxical prothrombotic tendencies of these drugs tend to be under-recognised due, perhaps, to their clinical infrequency. However, when these effects pertain, their consequences can be devastating. Here, we present a postoperative oncology patient who suffered a massive recrudescence of his lower limb venous thrombosis immediately after discontinuation of his heparin infusion, despite seemingly being adequately anticoagulated by warfarin therapy (INR > 2.0). We intend this case to graphically illustrate the theoretical considerations that must govern the perioperative use of these drugs in high-risk patients

    Estimated HIV Incidence in the United States, 2006–2009

    Get PDF
    Background The estimated number of new HIV infections in the United States reflects the leading edge of the epidemic. Previously, CDC estimated HIV incidence in the United States in 2006 as 56,300 (95% CI: 48,200–64,500). We updated the 2006 estimate and calculated incidence for 2007–2009 using improved methodology. Methodology We estimated incidence using incidence surveillance data from 16 states and 2 cities and a modification of our previously described stratified extrapolation method based on a sample survey approach with multiple imputation, stratification, and extrapolation to account for missing data and heterogeneity of HIV testing behavior among population groups. Principal Findings Estimated HIV incidence among persons aged 13 years and older was 48,600 (95% CI: 42,400–54,700) in 2006, 56,000 (95% CI: 49,100–62,900) in 2007, 47,800 (95% CI: 41,800–53,800) in 2008 and 48,100 (95% CI: 42,200–54,000) in 2009. From 2006 to 2009 incidence did not change significantly overall or among specific race/ethnicity or risk groups. However, there was a 21% (95% CI:1.9%–39.8%; p = 0.017) increase in incidence for people aged 13–29 years, driven by a 34% (95% CI: 8.4%–60.4%) increase in young men who have sex with men (MSM). There was a 48% increase among young black/African American MSM (12.3%–83.0%; p<0.001). Among people aged 13–29, only MSM experienced significant increases in incidence, and among 13–29 year-old MSM, incidence increased significantly among young, black/African American MSM. In 2009, MSM accounted for 61% of new infections, heterosexual contact 27%, injection drug use (IDU) 9%, and MSM/IDU 3%. Conclusions/Significance Overall, HIV incidence in the United States was relatively stable 2006–2009; however, among young MSM, particularly black/African American MSM, incidence increased. HIV continues to be a major public health burden, disproportionately affecting several populations in the United States, especially MSM and racial and ethnic minorities. Expanded, improved, and targeted prevention is necessary to reduce HIV incidence

    Intracranial V. cholerae Sialidase Protects against Excitotoxic Neurodegeneration

    Get PDF
    Converging evidence shows that GD3 ganglioside is a critical effector in a number of apoptotic pathways, and GM1 ganglioside has neuroprotective and noötropic properties. Targeted deletion of GD3 synthase (GD3S) eliminates GD3 and increases GM1 levels. Primary neurons from GD3S−/− mice are resistant to neurotoxicity induced by amyloid-β or hyperhomocysteinemia, and when GD3S is eliminated in the APP/PSEN1 double-transgenic model of Alzheimer's disease the plaque-associated oxidative stress and inflammatory response are absent. To date, no small-molecule inhibitor of GD3S exists. In the present study we used sialidase from Vibrio cholerae (VCS) to produce a brain ganglioside profile that approximates that of GD3S deletion. VCS hydrolyzes GD1a and complex b-series gangliosides to GM1, and the apoptogenic GD3 is degraded. VCS was infused by osmotic minipump into the dorsal third ventricle in mice over a 4-week period. Sensorimotor behaviors, anxiety, and cognition were unaffected in VCS-treated mice. To determine whether VCS was neuroprotective in vivo, we injected kainic acid on the 25th day of infusion to induce status epilepticus. Kainic acid induced a robust lesion of the CA3 hippocampal subfield in aCSF-treated controls. In contrast, all hippocampal regions in VCS-treated mice were largely intact. VCS did not protect against seizures. These results demonstrate that strategic degradation of complex gangliosides and GD3 can be used to achieve neuroprotection without adversely affecting behavior
    • …
    corecore