2,933 research outputs found

    Resummation Methods at Finite Temperature: The Tadpole Way

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    We examine several resummation methods for computing higher order corrections to the finite temperature effective potential, in the context of a scalar Ď•4\phi^4 theory. We show by explicit calculation to four loops that dressing the propagator, not the vertex, of the one-loop tadpole correctly counts ``daisy'' and ``super-daisy'' diagrams.Comment: 18 pages, LaTeX, CALT-68-1858, HUTP-93-A011, EFI-93-2

    Analysis of influenza vaccination coverage among the elderly in Genoa (Italy) based on a deprivation index, 2009-2013

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    Introduction. The elderly suffer the most influenza-related complications, and 90%of deaths due to influenza occur in older subjects. Consequently, the elderly are among the main targets of influenza vaccination campaigns. The use of deprivation indexes can help to identify subgroups with lower vaccination uptake. This study analyzed influenza vaccination coverage in elderly persons living in Genoa (Italy) in relation to a local Index of Socio-Economic and Health Deprivation (SEHDI) in order to identify population subgroups needing specific intervention to improve vaccination coverage. Methods. The study targeted subjects aged 65 65 years living in Genoa in the period 2009-2013. Information on vaccination coverage was provided by general practitioners and Local Health Units. A combination of linear regression, factor analysis and cluster analysis was used to construct the SEHDI at Census Tract (CT) level, on the basis of data from the 2011 Italian census. Results. In 2011, people aged 65 65 years accounted for the 27.7%of the population of Genoa. Most elderly subjects were assigned to either the medium (45.3%) or medium-high (32%) deprivation groups, while the percentages in the extreme tails were low (3.6%high deprivation; 1.3%low deprivation). Significant, nonlinear (p < 0.05 NL) relationships were observed in both sexes with regard to mortality due to all respiratory diseases (RD) and chronic obstructive pulmonary disease (COPD), with the highest Standardized Mortality Ratio (SMR) values in women in the high deprivation group of women (1.81, p < 0.05 RD; 1.79, p < 0.05 COPD). The SMRs for influenza and pneumonia showed a positive linear trend in women (p < 0.05) with the highest value in the high deprivation group (1.97, p < 0.05), while in men the trend was NL (p < 0.05). A positive linear trend (p < 0.05) was found with regard to vaccination coverage, which grew weakly as deprivation increased, up to the medium-high deprived group (from 34.6%to 44.4%). However, the high deprivation group showed the lowest value (33.3%). Conclusions. The results revealed a relationship between deprivation and influenza vaccination coverage in the elderly. This finding should be taken into account in the organization of vaccination campaigns and should prompt differentiated intervention in each local area

    HEP Applications Evaluation of the EDG Testbed and Middleware

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    Workpackage 8 of the European Datagrid project was formed in January 2001 with representatives from the four LHC experiments, and with experiment independent people from five of the six main EDG partners. In September 2002 WP8 was strengthened by the addition of effort from BaBar and D0. The original mandate of WP8 was, following the definition of short- and long-term requirements, to port experiment software to the EDG middleware and testbed environment. A major additional activity has been testing the basic functionality and performance of this environment. This paper reviews experiences and evaluations in the areas of job submission, data management, mass storage handling, information systems and monitoring. It also comments on the problems of remote debugging, the portability of code, and scaling problems with increasing numbers of jobs, sites and nodes. Reference is made to the pioneeering work of Atlas and CMS in integrating the use of the EDG Testbed into their data challenges. A forward look is made to essential software developments within EDG and to the necessary cooperation between EDG and LCG for the LCG prototype due in mid 2003.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics Conference (CHEP03), La Jolla, CA, USA, March 2003, 7 pages. PSN THCT00

    Interference Study of the chi_c0 (1^3P_0) in the Reaction Proton-Antiproton -> pi^0 pi^0

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    Fermilab experiment E835 has observed proton-antiproton annihilation production of the charmonium state chi_c0 and its subsequent decay into pi^0 pi^0. Although the resonant amplitude is an order of magnitude smaller than that of the non-resonant continuum production of pi^0 pi^0, an enhanced interference signal is evident. A partial wave expansion is used to extract physics parameters. The amplitudes J=0 and 2, of comparable strength, dominate the expansion. Both are accessed by L=1 in the entrance proton-antiproton channel. The product of the input and output branching fractions is determined to be B(pbar p -> chi_c0) x B(chi_c0 -> pi^0 pi^0)= (5.09 +- 0.81 +- 0.25) x 10^-7.Comment: 4 pages, 4 figures, Accepted by PRL (July 2003

    Subcritical Fluctuations at the Electroweak Phase Transition

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    We study the importance of thermal fluctuations during the electroweak phase transition. We evaluate in detail the equilibrium number density of large amplitude subcritical fluctuations and discuss the importance of phase mixing to the dynamics of the phase transition. Our results show that, for realistic Higgs masses, the phase transition can be completed by the percolation of the true vacuum, induced by the presence of subcritical fluctuations.Comment: RevTeX, 4 eps figs (uses epsf.sty), 26 pages, to be published in Phys. Rev.

    Gamma Lines without a Continuum: Thermal Models for the Fermi-LAT 130 GeV Gamma Line

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    Recent claims of a line in the Fermi-LAT photon spectrum at 130 GeV are suggestive of dark matter annihilation in the galactic center and other dark matter-dominated regions. If the Fermi feature is indeed due to dark matter annihilation, the best-fit line cross-section, together with the lack of any corresponding excess in continuum photons, poses an interesting puzzle for models of thermal dark matter: the line cross-section is too large to be generated radiatively from open Standard Model annihilation modes, and too small to provide efficient dark matter annihilation in the early universe. We discuss two mechanisms to solve this puzzle and illustrate each with a simple reference model in which the dominant dark matter annihilation channel is photonic final states. The first mechanism we employ is resonant annihilation, which enhances the annihilation cross-section during freezeout and allows for a sufficiently large present-day annihilation cross section. Second, we consider cascade annihilation, with a hierarchy between p-wave and s-wave processes. Both mechanisms require mass near-degeneracies and predict states with masses closely related to the dark matter mass; resonant freezeout in addition requires new charged particles at the TeV scale.Comment: 17 pages, 8 figure

    Efficacy and safety of honeybee and wasp tyrosine-adsorbed venom immunotherapy

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    It is acknowledged that any claim of efficacy of allergen immunotherapy must be done for each specific product, and this remains true also for venom immunotherapy (VIT). Thus, we evaluated the efficacy and safety of a specific tyrosine-adsorbed VIT for vespula spp. and honeybee in real-life

    Assessment of knowledge, attitudes, and propensity towards HPV vaccine of young adult students in Italy

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    Background: Human Papillomavirus (HPV) is a common sexually transmitted infection (STI), representing the main cause of genital warts and cervical cancer. This cross-sectional study evaluated knowledge and attitudes about HPV infection, related diseases, and prevention and propensity towards HPV vaccine among undergraduate students. Methods: An online and written survey about HPV and its prevention, targeted to young adults of both genders, was addressed to students attending health sciences and other schools at Universities of Genoa and Bari. Results: The overall median knowledge and attitude scores were 56.3% (25\u201375 p = 40\u201368.8%) and four out of five (25\u201375 p = 4\u20135), respectively. In the multivariate analysis, attending a health sciences university, using social networks 642 h a day, a history of STI, having heard about HPV and HPV vaccine previously resulted as predictors of higher knowledge scores. Having heard about HPV previously also predicted a high attitude score, together with a perceived economic status as good. Having Italian and healthcare worker parents, being employed, and following a specific diet, instead, predicted lower attitude score. Conclusions: Poor knowledge and good attitudes were found among undergraduates about HPV. In order to increase HPV vaccine compliance and the counselling skills of future healthcare workers, the improvement of training on HPV is needed
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