1,464 research outputs found

    Men??s circumcision status and women??s risk of HIV acquisition in Zimbabwe and Uganda

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    OBJECTIVE: To assess whether male circumcision of the primary sex partner is associated with women's risk of HIV. DESIGN: Data were analyzed from 4417 Ugandan and Zimbabwean women participating in a prospective study of hormonal contraception and HIV acquisition. Most were recruited from family planning clinics; some in Uganda were referred from higher-risk settings such as sexually transmitted disease clinics. METHODS: Using Cox proportional hazards models, time to HIV acquisition was compared for women with circumcised or uncircumcised primary partners. Possible misclassification of male circumcision was assessed using sensitivity analysis. RESULTS: At baseline, 74% reported uncircumcised primary partners, 22% had circumcised partners and 4% had partners of unknown circumcision status. Median follow-up was 23 months, during which 210 women acquired HIV (167, 34, and 9 women whose primary partners were uncircumcised, circumcised, or of unknown circumcision status, respectively). Although unadjusted analyses indicated that women with circumcised partners had lower HIV risk than those with uncircumcised partners, the protective effect disappeared after adjustment for other risk factors [hazard ratio (HR), 1.03; 95% confidence interval (CI), 0.69-1.53]. Subgroup analyses suggested a non-significant protective effect of male circumcision on HIV acquisition among Ugandan women referred from higher-risk settings: adjusted HR 0.16 (95% CI, 0.02-1.25) but little effect in Ugandans (HR, 1.33; 95% CI, 0.72-2.47) or Zimbabweans (HR, 1.12; 95% CI, 0.65-1.91) from family planning clinics. CONCLUSIONS: After adjustment, male circumcision was not significantly associated with women's HIV risk. The potential protection offered by male circumcision for women recruited from high-risk settings warrants further investigation

    Landscape Mapping of Functional Proteins in Insulin Signal Transduction and Insulin Resistance: A Network-Based Protein-Protein Interaction Analysis

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    The type 2 diabetes has increased rapidly in recent years throughout the world. The insulin signal transduction mechanism gets disrupted sometimes and it's known as insulin-resistance. It is one of the primary causes associated with type-2 diabetes. The signaling mechanisms involved several proteins that include 7 major functional proteins such as INS, INSR, IRS1, IRS2, PIK3CA, Akt2, and GLUT4. Using these 7 principal proteins, multiple sequences alignment has been created. The scores between sequences also have been developed. We have constructed a phylogenetic tree and modified it with node and distance. Besides, we have generated sequence logos and ultimately developed the protein-protein interaction network. The small insulin signal transduction protein arrangement shows complex network between the functional proteins

    Characterization of an Ionization Readout Tile for nEXO

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    A new design for the anode of a time projection chamber, consisting of a charge-detecting "tile", is investigated for use in large scale liquid xenon detectors. The tile is produced by depositing 60 orthogonal metal charge-collecting strips, 3~mm wide, on a 10~\si{\cm} ×\times 10~\si{\cm} fused-silica wafer. These charge tiles may be employed by large detectors, such as the proposed tonne-scale nEXO experiment to search for neutrinoless double-beta decay. Modular by design, an array of tiles can cover a sizable area. The width of each strip is small compared to the size of the tile, so a Frisch grid is not required. A grid-less, tiled anode design is beneficial for an experiment such as nEXO, where a wire tensioning support structure and Frisch grid might contribute radioactive backgrounds and would have to be designed to accommodate cycling to cryogenic temperatures. The segmented anode also reduces some degeneracies in signal reconstruction that arise in large-area crossed-wire time projection chambers. A prototype tile was tested in a cell containing liquid xenon. Very good agreement is achieved between the measured ionization spectrum of a 207^{207}Bi source and simulations that include the microphysics of recombination in xenon and a detailed modeling of the electrostatic field of the detector. An energy resolution σ/E\sigma/E=5.5\% is observed at 570~\si{keV}, comparable to the best intrinsic ionization-only resolution reported in literature for liquid xenon at 936~V/\si{cm}.Comment: 18 pages, 13 figures, as publishe

    Sensitivity and discovery potential of the proposed nEXO experiment to neutrinoless double beta decay

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    The next-generation Enriched Xenon Observatory (nEXO) is a proposed experiment to search for neutrinoless double beta (0νββ0\nu\beta\beta) decay in 136^{136}Xe with a target half-life sensitivity of approximately 102810^{28} years using 5×1035\times10^3 kg of isotopically enriched liquid-xenon in a time projection chamber. This improvement of two orders of magnitude in sensitivity over current limits is obtained by a significant increase of the 136^{136}Xe mass, the monolithic and homogeneous configuration of the active medium, and the multi-parameter measurements of the interactions enabled by the time projection chamber. The detector concept and anticipated performance are presented based upon demonstrated realizable background rates.Comment: v2 as publishe

    Gravitational Waves From Known Pulsars: Results From The Initial Detector Era

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    We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyAustralian Research CouncilInternational Science Linkages program of the Commonwealth of AustraliaCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Economia y CompetitividadConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsNetherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFOCUS Programme of Foundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space AdministrationOTKA of HungaryLyon Institute of Origins (LIO)National Research Foundation of KoreaIndustry CanadaProvince of Ontario through the Ministry of Economic Development and InnovationNational Science and Engineering Research Council CanadaCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationAstronom
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