6,750 research outputs found

    Ground Water Quality Effects on Domestic Water Utilization

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    The work upon which this report is based was supported in part by funds (Project A-040-ALAS) provided by the United States Department of the Interior, Office of Water Resources Research, as authorized under the Water Resources Act of 1964, as amended

    An O\u27Neill Institute Briefing Paper: Ebola, the World Health Organization, and Beyond: Toward a Framework for Global Health Security

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    The West African Ebola epidemic has demonstrated that the world remains ill-prepared to respond to infectious disease outbreaks. A host of institutions are now reviewing what went wrong, and new institutions are being considered, including an African Centers for Disease Control and Prevention and World Bank-initiated Pandemic Emergency Facility. The World Health Organization itself failed in one of its core functions by allowing a preventable infectious disease to spiral out of control in the world’s poorest region. The 68th World Health Assembly (WHA), held in May 2015, provided an opportunity for the Organization to reflect on what went wrong and reform the organization to be better able to address the next epidemic. In this Briefing Paper we lay out the present landscape, including reforms needed of the International Health Regulations, and assess the strengths and weaknesses of the outcomes of the 68th WHA, including integrating WHO’s outbreak and emergency response programs; creating a global health emergency workforce, deployable on short notice; and setting up a global health emergency contingency fund. We also consider the vital structural issues the WHA failed to effectively address, including bolstering WHO’s core funding, increasing coherence between the WHO headquarters and regional offices, and enhancing civil society engagement

    Isotopic study of oxygen diffusion in oxide coatings

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    Diffusion of oxygen in thin films of silicon dioxide was studied using oxygen isotopically enriched in oxygen of atomic mass 18 (O-18). This subject is of interest because thin films of dielectrics such as SiO2 are proposed for use as a protective coatings for solar mirrors in low Earth orbit, which is a strongly oxidizing environment. Films of this material were prepared with a direct current magnetron using reactive sputtering techniques. To produce (O-18)- enriched SiO2, a standard 3.5-in.-diameter silicon wafer was reactively sputtered using (O-18)-enriched (95 percent) oxygen as the plasma feed gas. The films were characterized using Rutherford backscattering and Secondary Ion Mass Spectrometer (SIMS) to establish stoichiometry and purity. Subsequently, the films were exposed to an air-derived oxygen plasma in a standard laboratory plasma reactor for durations of up to 10 hr. The concentration ratio of O-16 as a function of depth was determined using SIMS profiling and compared to a baseline, nonplasma exposed sample. A value for the diffusivity of oxygen near the surface of these films was obtained and found to be about 10(-15)sq cm/sec

    Cis-regulatory basis of sister cell type divergence in the vertebrate retina

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    Multicellular organisms evolved via repeated functional divergence of transcriptionally related sister cell types, but the mechanisms underlying sister cell type divergence are not well understood. Here, we study a canonical pair of sister cell types, retinal photoreceptors and bipolar cells, to identify the ke

    Improved methods for simulating nearly extremal binary black holes

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    Astrophysical black holes could be nearly extremal (that is, rotating nearly as fast as possible); therefore, nearly extremal black holes could be among the binaries that current and future gravitational-wave observatories will detect. Predicting the gravitational waves emitted by merging black holes requires numerical-relativity simulations, but these simulations are especially challenging when one or both holes have mass mm and spin SS exceeding the Bowen-York limit of S/m2=0.93S/m^2=0.93. We present improved methods that enable us to simulate merging, nearly extremal black holes more robustly and more efficiently. We use these methods to simulate an unequal-mass, precessing binary black hole coalescence, where the larger black hole has S/m2=0.99S/m^2=0.99. We also use these methods to simulate a non-precessing binary black hole coalescence, where both black holes have S/m2=0.994S/m^2=0.994, nearly reaching the Novikov-Thorne upper bound for holes spun up by thin accretion disks. We demonstrate numerical convergence and estimate the numerical errors of the waveforms; we compare numerical waveforms from our simulations with post-Newtonian and effective-one-body waveforms; we compare the evolution of the black-hole masses and spins with analytic predictions; and we explore the effect of increasing spin magnitude on the orbital dynamics (the so-called "orbital hangup" effect).Comment: 18 pages, 18 figure

    Mandatory SARS-CoV-2 Vaccinations in K-12 Schools, Colleges/Universities, and Businesses

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    The Centers for Disease Control and Prevention (CDC) recently issued guidance that fully vaccinated individuals can safely remove masks and end social distancing in most indoor settings. Educational facilities and businesses are faced with whether and how to differentiate between vaccinated and unvaccinated individuals, including requiring proof of vaccination. Mandatory vaccination has historically served as a tool to reach and sustain high immunization coverage and to prevent transmission in K-12 schools, colleges/universities, and health care facilities. Vaccine mandates could extend to workers and customers in businesses to ensure safer environments. This Viewpoint examines the epidemiologic, public health, and legal considerations for mandatory SARS-CoV-2 vaccinations in each setting

    Data Transfer to Non-volatile Memory (or Persistent Memory) During Input Power Loss

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    In a critical server losing its input voltage/power, the server goes down after 10/20ms of hold-up time. In these hold-up time the data need to be transferred from volatile memory to non-volatile memory (NVDIMM). For years this process is being done successfully, by transferring the data during this 10/20ms hold-up time. However, this process is having the disadvantage of the server going down for each and every event of input power loss using NVDIMMs platforms. To overcome this disadvantage, a new method or technique is proposed in this publication/disclosure (Fig 1). The proposed technique utilizes the signal (called bulk voltage). Whenever, the energy levels (called bulk voltage) in a power supply becomes low, the server starts transferring the data (compared to each loss of input power earlier) to non-volatile memory reducing the number of shut downs of the server. If the input power loss duration is from 10ms to 80ms depending upon the load on the server, the shutdown of the server can be avoided completely. The cost of this feature is miniscule compared to the cost of adding UPS/mega cell/Super cap in each and every server/platform
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