1,004 research outputs found

    A Geospatial Analysis of CDC-funded HIV Prevention Programs for African Americans in the United States

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    Given the increase in HIV/AIDS infection rates among racial and ethnic minorities, particularly African Americans, this study was undertaken as part of a larger research effort to examine the distribution of HIV prevention services focusing on African American populations within the United States. Data were gathered via a national survey of community-based organizations (CBOs) funded by the Centers for Disease Control and Prevention (CDC). A geocoded national database was constructed to identify, locate, and map these HIV prevention programs. A total of 1,020 CBOs responded to the survey, yielding a response rate of 70.3%. These CBOs administered a total of 3,028 HIV prevention programs. Data describing intervention types and persons served, combined with the address and service area of responding CBOs, were integrated with census data (2000) and analyzed by using a geographic information system (GIS). The results of our national level analysis show that HIV prevention services for African Americans have fair coverage where African Americans comprise a substantial proportion of the population in urban areas in northeastern states, but that HIV prevention services for African Americans are inadequately distributed in the southeastern states. A local-level analysis was conducted for Alabama, where 68% of HIV/AIDS cases are among African Americans. Specific interventions such as street and community outreach, health communications, and public information are fairly well provided to African Americans in more urban cities in Alabama, however, individual- and group-level interventions have poor coverage in rural areas where a large percentage of African-Americans live. Overall, our study illustrates that the use of GIS adds value when used with other data sources to provide prevention services that are accessible to the populations most in need

    Precision determination of absolute neutron flux

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    A technique for establishing the total neutron rate of a highly-collimated monochromatic cold neutron beam was demonstrated using a method of an alpha-gamma counter. The method involves only the counting of measured rates and is independent of neutron cross sections, decay chain branching ratios, and neutron beam energy. For the measurement, a target of 10B-enriched boron carbide totally absorbed the neutrons in a monochromatic beam, and the rate of absorbed neutrons was determined by counting 478keV gamma rays from neutron capture on 10B with calibrated high-purity germanium detectors. A second measurement based on Bragg diffraction from a perfect silicon crystal was performed to determine the mean de Broglie wavelength of the beam to a precision of 0.024 %. With these measurements, the detection efficiency of a neutron monitor based on neutron absorption on 6Li was determined to an overall uncertainty of 0.058 %. We discuss the principle of the alpha-gamma method and present details of how the measurement was performed including the systematic effects. We also describe how this method may be used for applications in neutron dosimetry and metrology, fundamental neutron physics, and neutron cross section measurements.Comment: 44 page

    The Effect of Substituting High Oil Corn as a Replacement for Normal Corn in Nursery Pig Diets

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    The objective of this study was to determine the production and monetary effects of using High Oil Corn (HOC) in a nursery phase feeding program and monitor growth performance differences through marketing. Two groups of weaned crossbred pigs (n = 293 trial 1; n = 265 trial 2) were segregated by sex and weight into small, medium and heavy groups and allotted to 12 nursery pens. Pigs received one of two dietary treatments which included; a transitional phase I diet for 7 days; a commercial corn soy based phase II diet (NCII) for 14 days and a phase III diet (NCIII) for 7 days; a HOC soy based phase II diet for 21 days and the NCIII diet for 7 days. Body weight, Average daily feed intake and Gain/Feed (G/F) ratios were measured weekly during the nursery period. Pigs were transferred to a grow/finish barn on d 28 post-weaning. Body weight, Backfat (BF) and Longissimus Muscle Area (LMA) at the 10th and last ribs were ultrasonically evaluated 4 times prior to market. Average daily gain of nursery pigs on the three-phase NC diet was greater than pigs fed the HOC two-phase diet at d 21 post-weaning (p = .0034) and 28 post-weaning (p = .0128). ADG for heavy pigs was greater (p = .0001) than that of medium and lightweight pigs and no treatment�weight group interactions were observed (p = .2043). Pigs fed the three-phase diet had greater G/F ratios than pigs fed the HOC two-phase diet at d 21 (p = .0137) and 28 (p = .0134). LEA for pigs fed the three-phase diet was greater than pigs fed the HOC two-phase diet when measured on d 28 at the 10th (p = .0565) and last rib (p = .0370). Even though pigs were fed alike in the grow-finish period, ADG of pigs fed the three-phase nursery diet was greater (p = .0106) than that of pigs fed the HOC two-phase nursery diet. There were no differences in the predicted 114 kg weight (p = .2658). However, economic differences were noted for the two treatments with the HOC two-phase diet lowering the cost of production of marketed animals. There were no treatment differences for average daily lean growth per day (p = .8611) or percentage lean of carcasses (p = .2865). The results did not support removal of the transitional phase I diet and the substitution of HOC for NC in a phase II diet fed to nursery pigs for maximal nursery growth, nor was carcass composition of pigs at marketing adversely affected

    Phototesting and photoprotection in LE

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    Photosensitivity and induction of skin lesions following UV radiation is a common problem of patients with cutaneous and systemic forms of lupus erythematosus. The detrimental effect of UV radiation to patients with lupus erythematosus was already recognized in the last century. Skin lesions can now be provoked under standardized conditions allowing the diagnosis and classification of patients with photosensitive disorders. The aim of this review is to give an overview on the history, test procedure and test results in patients with lupus erythematosus

    WRF-CMAQ two-way coupled system with aerosol feedback: software development and preliminary results

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    Air quality models such as the EPA Community Multiscale Air Quality (CMAQ) require meteorological data as part of the input to drive the chemistry and transport simulation. The Meteorology-Chemistry Interface Processor (MCIP) is used to convert meteorological data into CMAQ-ready input. Key shortcoming of such one-way coupling include: excessive temporal interpolation of coarsely saved meteorological input and lack of feedback of atmospheric pollutant loading on simulated dynamics. We have developed a two-way coupled system to address these issues. A single source code principle was used to construct this two-way coupling system so that CMAQ can be consistently executed as a stand-alone model or part of the coupled system without any code changes; this approach eliminates maintenance of separate code versions for the coupled and uncoupled systems. The design also provides the flexibility to permit users: (1) to adjust the call frequency of WRF and CMAQ to balance the accuracy of the simulation versus computational intensity of the system, and (2) to execute the two-way coupling system with feedbacks to study the effect of gases and aerosols on short wave radiation and subsequent simulated dynamics. Details on the development and implementation of this two-way coupled system are provided. When the coupled system is executed without radiative feedback, computational time is virtually identical when using the Community Atmospheric Model (CAM) radiation option and a slightly increased (~8.5 %) when using the Rapid Radiative Transfer Model for GCMs (RRTMG) radiation option in the coupled system compared to the offline WRF-CMAQ system. Once the feedback mechanism is turned on, the execution time increases only slightly with CAM but increases about 60 % with RRTMG due to the use of a more detailed Mie calculation in this implementation of feedback mechanism. This two-way model with radiative feedback shows noticeably reduced bias in simulated surface shortwave radiation and 2 m temperatures as well improved correlation of simulated ambient ozone and PM<sub>2.5</sub> relative to observed values for a test case with significant tropospheric aerosol loading from California wildfires

    Uric Acid-Induced Adipocyte Dysfunction Is Attenuated by HO-1 Upregulation: Potential Role of Antioxidant Therapy to Target Obesity

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    Increased uric acid levels have been implicated in the pathogenesis of metabolic syndrome. To examine the mechanisms by which this occurs, we hypothesized that an increase in heme oxygenase 1, a potent antioxidant gene, will decrease uric acid levels and adipocyte dysfunction via suppression of ROS and xanthine oxidase (XO) levels. We examined the effect of uric acid on adipogenesis in human mesenchymal stem cells (MSCs) in the presence and absence of cobalt protoporphyrin (CoPP), an HO-1 inducer, and tin mesoporphyrin (SnMP), an HO activity inhibitor. Uric acid increased adipogenesis by increasing NADPH oxidase expression and elevation in the adipogenesis markers C/EBPα, PPARγ, and Mest, while decreasing small lipid droplets and Wnt10b levels. We treated MSCs with fructose, a fuel source that increases uric acid levels. Our results showed that fructose increased XO expression as compared to the control and concomitant treatment with CoPP significantly decreased XO expression and uric acid levels. These beneficial effects of CoPP were reversed by SnMP, supporting a role for HO activity in mediating these effects. These findings demonstrate that increased levels of HO-1 appear crucial in modulating the phenotype of adipocytes exposed to uric acid and in downregulating XO and NADPH oxidase levels

    Measurement of the Neutron Lifetime by Counting Trapped Protons in a Cold Neutron Beam

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    A measurement of the neutron lifetime τn\tau_{n} performed by the absolute counting of in-beam neutrons and their decay protons has been completed. Protons confined in a quasi-Penning trap were accelerated onto a silicon detector held at a high potential and counted with nearly unit efficiency. The neutrons were counted by a device with an efficiency inversely proportional to neutron velocity, which cancels the dwell time of the neutron beam in the trap. The result is τn=(886.6±1.2[stat]±3.2[sys])\tau_{n} = (886.6\pm1.2{\rm [stat]}\pm3.2{\rm [sys]}) s, which is the most precise measurement of the lifetime using an in-beam method. The systematic uncertainty is dominated by neutron counting, in particular the mass of the deposit and the 6^{6}Li({\it{n,t}}) cross section. The measurement technique and apparatus, data analysis, and investigation of systematic uncertainties are discussed in detail.Comment: 71 pages, 20 figures, 9 tables; submitted to PR
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