284 research outputs found

    Infinite-dimensional representations of the rotation group and Dirac's monopole problem

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    Within the context of infinite-dimensional representations of the rotation group the Dirac monopole problem is studied in details. Irreducible infinite-dimensional representations, being realized in the indefinite metric Hilbert space, are given by linear unbounded operators in infinite-dimensional topological spaces, supplied with a weak topology and associated weak convergence. We argue that an arbitrary magnetic charge is allowed, and the Dirac quantization condition can be replaced by a generalized quantization rule yielding a new quantum number, the so-called topological spin, which is related to the weight of the Dirac string.Comment: JHEP style. Extended version of hep-th/0403146. Revised version, title and some notations are changed. References and Appendix B are adde

    Cuban creole pig in Bayamo jurisdiction

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    The former jurisdiction of Bayamo, as political colonial division began its way in the century XVI, after its foundation in 1513 as the second Cuban village. Currently the Bayamo village is integrated by 15 local districts, an extension of 835.12 km2 and a population 68690 inhabitants. In spite of have elapsed more than 470 years from the arrival of the first pigs from Spain, this region has maintained 6176 breeders of this native pig breed as direct descendant of the Mediterranean pigs. In this work is presented the racial, ecological and human factors, that they have permitted the maintenance of this population with origin in the Iberian pig.La antigua jurisdicción de Bayamo, como división política de la colonia comenzó su andadura en el siglo XVI, tras su fundación en 1513 como la segunda villa de Cuba. Actualmente el municipio de Bayamo lo integran 15 consejos populares, una superficie de 835,12 km2 y una población de 68690 habitantes. A pesar de haber transcurrido mås de 470 años desde la llegada de los primeros cerdos desde España, esta región ha mantenido 6176 reproductores de la raza cerdo Criollo como descendiente directo de los cerdos mediterråneos. En este trabajo se presenta los factores racial, ecológico y humano, que han permitido la perdurabilidad de esta raza descendiente del cerdo Ibérico

    Electron energy loss and induced photon emission in photonic crystals

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    The interaction of a fast electron with a photonic crystal is investigated by solving the Maxwell equations exactly for the external field provided by the electron in the presence of the crystal. The energy loss is obtained from the retarding force exerted on the electron by the induced electric field. The features of the energy loss spectra are shown to be related to the photonic band structure of the crystal. Two different regimes are discussed: for small lattice constants aa relative to the wavelength of the associated electron excitations λ\lambda, an effective medium theory can be used to describe the material; however, for a∌λa\sim\lambda the photonic band structure plays an important role. Special attention is paid to the frequency gap regions in the latter case.Comment: 12 pages, 7 figure

    Analysis of grass pollen concentrations in the atmosphere of several spanish sites

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    Characterization of modular deposits for urban drainage networks using CFD techniques

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    [EN] The growing urban development of population centers in much of the world joined with the significant effects of climate change are causing an increasingly important and recurring increase of the damage caused by flooding. Much of the drainage networks of cities were designed for precipitation characteristics and return periods that have proved to be insufficient with the lapse of time. Therefore, solutions need to be addressed both to reduce runoff generated flows as to control circulating ones through the rainwater drainage networks. All these flow control rain technologies are commonly known as SUDS (Sustainable Urban Drainage), term that encompasses a multitude of solutions to control runoff although many of them require significant costs that make them practically unviable. Therefore, not only should focus on reducing runoff input to the network but also in the flow control techniques development. The idea is to design strategies to reduce flow rain peaks and maximize the capacity of existing networks. The use of detention and storm tanks for flood control is a solution increasingly used as an alternative one to control increased rainfall caused by climate change [1]. Nature and execution of storm tanks can be very diverse, from conventional way based on concrete structures to the most innovative ones in which modular structures are employed to improve the construction speed if many modular units are required at the same time that minimizing urban supply disruption is achieved. Currently, a wide range of modular structures exists on the market with both, different geometries and sizes. In this study the Aquacell brand supplied by Mexichem-PAVCO in Colombia shown in Fig. 1 has been chosen for the development of this study.S849218

    Arsenic exposure, diabetes-related genes and diabetes prevalence in a general population from Spain

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    Inorganic arsenic exposure may be associated with diabetes, but the evidence at low-moderate levels is not sufficient. Polymorphisms in diabetes-related genes have been involved in diabetes risk. We evaluated the association of inorganic arsenic exposure on diabetes in the Hortega Study, a representative sample of a general population from Valladolid, Spain. Total urine arsenic was measured in 1451 adults. Urine arsenic speciation was available in 295 randomly selected participants. To account for the confounding introduced by non-toxic seafood arsenicals, we designed a multiple imputation model to predict the missing arsenobetaine levels. The prevalence of diabetes was 8.3%. The geometric mean of total arsenic was 66.0 ”g/g. The adjusted odds ratios (95% confidence interval) for diabetes comparing the highest with the lowest tertile of total arsenic were 1.76 (1.01, 3.09) and 2.14 (1.47, 3.11) before and after arsenobetaine adjustment, respectively. Polymorphisms in several genes including IL8RA, TXN, NR3C2, COX5A and GCLC showed suggestive differential associations of urine total arsenic with diabetes. The findings support the role of arsenic on diabetes and the importance of controlling for seafood arsenicals in populations with high seafood intake. Suggestive arsenic-gene interactions require confirmation in larger studies

    Quality of life in hidradenitis suppurativa : Validation of the hsqol-24

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    Altres ajuts: reports grants, personal fees, non-financial support and other from Abbvie, Almirall, Amgen, Boehringer, Celgene, Janssen-Cilag, Leo Pharma, Lilly, MSD-Schering-Plough, Novartis, Pfizer and UCB, outside the submitted work. TGC reports personal fees from Lilly and Novartis, outside the submitted work. LP reports grants and personal fees from AbbVie, Almirall, Amgen, Boehringer Ingelheim, Celgene, Janssen, Leo-Pharma, Lilly, Novartis, Pfizer, Regeneron, Roche, Sanofi, and UCB, personal fees from Baxalta, Biogen, Fresenius-Kabi, JS Biocad, Mylan, Sandoz, Samsung-Bioepis, and Bristol Myers Squibb, outside the submitted work. The other authors have no conflicts of interest to declare.To date, there are no disease-specific instruments in Spanish to assess quality of life of patients with hidra-denitis suppurativa. A multicentre study was pre-viously carried out in Spain between 2016 and 2017 to develop the Hidradenitis Suppurativa Quality of Life-24 (HSQoL-24), a disease-specific questionnaire to assess quality of life in patients with hidradenitis suppurativa. The objectives of this study are to revali-date the HSQoL-24 in Spanish with a larger sample of patients, and to present the English version. In this multi centre study in Spain, patients with hidradenitis suppurativa completed the HSQoL-24, the Dermatology Life Quality Index and the Skindex-29. The Hurley staging system was used to assess the severity of the disease. Validation of the questionnaire was carried out in 130 patients, of whom 75 (57.7%) were women. This study demonstrates adequate values of reliability and validity of the HSQoL-24, confirming the previous test re-test validation and making this questionnaire one of wide clinical validity in terms of results perceiv-ed by patients

    Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

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    Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

    Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

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    This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio
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