36,721 research outputs found

    Inclusive and effective bulk viscosities in the hadron gas

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    We estimate the temperature dependence of the bulk viscosity in a relativistic hadron gas. Employing the Green-Kubo formalism in the SMASH (Simulating Many Accelerated Strongly-interacting Hadrons) transport approach, we study different hadronic systems in increasing order of complexity. We analyze the (in)validity of the single exponential relaxation ansatz for the bulk-channel correlation function and the strong influence of the resonances and their lifetimes. We discuss the difference between the inclusive bulk viscosity of an equilibrated, long-lived system, and the effective bulk viscosity of a short-lived mixture like the hadronic phase of relativistic heavy-ion collisions, where the processes whose inverse relaxation rate are larger than the fireball duration are excluded from the analysis. This clarifies the differences between previous approaches which computed the bulk viscosity including/excluding the very slow processes in the hadron gas. We compare our final results with previous hadron gas calculations and confirm a decreasing trend of the inclusive bulk viscosity over entropy density as temperature increases, whereas the effective bulk viscosity to entropy ratio, while being lower than the inclusive one, shows no strong dependence to temperature.Comment: 23 pages, 13 figure

    Margins within margins?: voices Speaking through a study of the provision of an educational program for the children of one Australian show circuit

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    This paper examines the tactics used by the Showmen's Guild of Australasia in successfully lobbying for the development of a distance education program for their children. The Guild is considered to be a 'marginalized' group, meaning members have less access to wealth, power, and status. Since 1930, members of the Showmen's Guild and their families have traveled from town to town providing agricultural and equestrian shows. Despite the diversity of backgrounds and experiences among people connected with the show circuit, the Guild is highly organized and has been politically active. Informal sanctions have been effective in enforcing group discipline and in presenting the image of a single body of opinion. In addition, investment in sophisticated machinery and technology has resulted in show people having the financial resources to buy homes and have a political voice via more 'normalized channels'. Although members learn early that they are a marginalized group and are perceived as different from the mainstream, the group maintains close ties and often celebrates its difference. Implications for educational program development center on the goals of educational programs designed for disadvantaged groups, and the status of other marginalized groups and their efforts to contest their marginalized status. (LP

    Hydrogen Generation Catalyzed by Fluorinated Diglyoxime−Iron Complexes at Low Overpotentials

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    Fe^(II) complexes containing the fluorinated ligand 1,2-bis(perfluorophenyl)ethane-1,2-dionedioxime (dAr^FgH_2; H = dissociable proton) exhibit relatively positive Fe^(II/I) reduction potentials. The air-stable difluoroborated species [(dAr^FgBF_2)_2Fe(py)_2] (2) electrocatalyzes H_2 generation at −0.9 V vs SCE with i_(cat)/i_p ≈ 4, corresponding to a turnover frequency (TOF) of ~ 20 s^(–1) [Faradaic yield (FY) = 82 ± 13%]. The corresponding monofluoroborated, proton-bridged complex [(dArFg2H-BF2)Fe(py)2] (3) exhibits an improved TOF of ~ 200 s^(–1) (i_(cat)/i_p ≈ 8; FY = 68 ± 14%) at −0.8 V with an overpotential of 300 mV. Simulations of the electrocatalytic cyclic voltammograms of 2 suggest rate-limiting protonation of an Fe“0” intermediate (k_(RLS) ≈ 200 M^(–1) s^(–1)) that undergoes hydride protonation to form H_2. Complex 3 likely reacts via protonation of an Fe^I intermediate that subsequently forms H_2 via a bimetallic mechanism (k_(RLS) ≈ 2000 M^(–1) s^(–1)). 3 catalyzes production at relatively positive potentials compared with other iron complexes

    Economic Value of the Oil and Gas Resources on the Outer Continential Shelf

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    A theoretical framework for estimating the economic value of the federal government's offshore oil and gas resources is developed. This framework is then applied to geological and economic data generated by the Minerals Management Service in support of their five-year leasing plan. With an 8 percent real discount rate and a 1 percent real price growth rate, the remaining economic rent as of 1987 on the reserves plus the undiscovered offshore oil and gas resources is estimated at 118.6billion(1987dollars).Thepresentvalueofthegovernmentâ€Čsreceiptsfromcashbonusandroyaltypaymentsonthesedepositsisestimatedat118.6 billion (1987 dollars). The present value of the government's receipts from cash bonus and royalty payments on these deposits is estimated at 37.2 billion. Over 80 percent of the remaining economic rent is derived from developed reserve deposits located in the Gulf of Mexico. The private sector has previously paid cash bonuses for the leases located on those deposits and financed the installation of the development platforms. Because of this, the government will collect only a small portion, approximately 22 percent, of the rent remaining on those reserves.Environmental Economics and Policy, Resource /Energy Economics and Policy,

    Human Papillomavirus (HPV) Vaccination Status Among University Freshmen in Hawai‘i

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    Purpose/Background: The HPV vaccine provides immunity against nine HPV strains that cause cancer and genital warts. It is recommended for 11 to 12 year olds, and catch-up immunization is recommended for females 13 to 26 years old and males 13 to 21 years old. College students represent an important population for HPV vaccination due to their increased risk for HPV infection. Despite the benefits of the HPV vaccine, its coverage rates are low in Hawaii. Hawai‘i is the home of two large universities on two islands that are representative of Hawai‘i’s populations, including Native Hawaiians, Filipinos, and Pacific Islanders. The purpose of this study was to assess the current HPV and HPV vaccine knowledge, barriers and beliefs among incoming Freshmen university students at University of Hawai‘i at Mānoa and University of Hawai‘i at Hilo. Materials & Methods: In 2016, 200 University of Hawai‘i at Mānoa (UHM) and University of Hawai‘i at Hilo (UHH) Freshmen students responded to a survey that assessed their knowledge and awareness of HPV, the HPV vaccine, their current vaccination status, and barriers and motivators to vaccination. Descriptive statistics were used to summarize each survey variable first for all students and then separately for each campus. Results: Overall 76% of Freshmen from both campuses heard of the HPV vaccine and 54% reported hearing it from their health care provider. Only 28% UHM and 23% UHH Freshmen students have received partial (1-2 shots) or completed doses of the HPV vaccine. For those who received the vaccine, 45% reported that they were told by their parent and 43% were told by their doctor. For the 147 students who did not receive the vaccine, 28% reported that they are still not sure to get it and 20% need more information. Their main reasons for not receiving the HPV vaccine were: their doctor did not mention the vaccine to him/her (44%), he/she never knew about the vaccine (18%), and they don\u27t know enough about the vaccine (17%). Discussion/Conclusion: Although the HPV vaccine has been available for 13 years, young adults remain unvaccinated. Freshmen students reported that they are informed about the vaccine, but were not vaccinated because of the lack of parental and/or healthcare provider recommendation. With no active education campaigns in Hawaii promoting the HPV vaccine at college campuses, a first step to increasing vaccination rates is to develop a health education campaign to inform students of the HPV vaccine and its availability at campus clinics and neighboring pharmacies

    Addressing spin transitions on 209Bi donors in silicon using circularly-polarized microwaves

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    Over the past decade donor spin qubits in isotopically enriched 28^{28}Si have been intensely studied due to their exceptionally long coherence times. More recently bismuth donor electron spins have become popular because Bi has a large nuclear spin which gives rise to clock transitions (first-order insensitive to magnetic field noise). At every clock transition there are two nearly degenerate transitions between four distinct states which can be used as a pair of qubits. Here it is experimentally demonstrated that these transitions are excited by microwaves of opposite helicity such that they can be selectively driven by varying microwave polarization. This work uses a combination of a superconducting coplanar waveguide (CPW) microresonator and a dielectric resonator to flexibly generate arbitrary elliptical polarizations while retaining the high sensitivity of the CPW

    Screening of a HUVEC cDNA library with transplant-associated coronary artery disease sera identifies RPL7 as a candidate autoantigen associated with this disease.

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    A HUVEC cDNA library was screened with sera from two patients who had developed transplant-associated coronary artery disease (TxCAD) following cardiac transplantation. A total of six positive clones were isolated from a primary screen of 40 000 genes. Subsequent DNA sequence analysis identified these to be lysyl tRNA synthetase, ribosomal protein L7, ribosomal protein L9, beta transducin and TANK. Another gene whose product could not be identified showed homology to a human cDNA clone (DKFZp566M063) derived from fetal kidney. Full-length constructs of selected genes were expressed as his-tag recombinant fusion proteins and used to screen a wider patient base by ELISA to determine prevalence and association with TxCAD. Of these ribosomal protein L7 showed the highest prevalence (55.6%) with TxCAD sera compared to 10% non-CAD
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