10,482 research outputs found
N*(1535) electroproduction at high Q2
A covariant spectator quark model is applied to study the gamma N -> N*(1535)
reaction in the large Q2 region. Starting from the relation between the nucleon
and N*(1535) systems, the N*(1535) valence quark wave function is determined
without the addition of any parameters. The model is then used to calculate the
gamma N -> N*(1535) transition form factors. A very interesting, useful
relation between the A12 and S12 helicity amplitudes for Q2 > GeV^2, is also
derived.Comment: Contribution to the proceedings of the 8th International Workshop on
the Physics of Excited Nucleons (NSTAR2011), Jefferson Lab, Newport News, VA,
USA, May 17-20, 201
Evaluation of a collaborative photography workshop using the iPad 2 as an accessible technology for participants who are blind, visually impaired and sighted working collaboratively
A workshop using iPads to train photographers who are blind, visually impaired and sighted is evaluated using a model of inclusive technical capital. It was hypothesized that all participants would find iPad apps accessible. It was found that iPads were good introductory devices, but experienced participants who are blind and sighted still preferred specialized cameras
Perceptions of Changes and Impacts Accompanying the Introduction of Management Planning to the Woburn/Clarke's Court Bay MPA, Grenada
The continuum limit of the quark mass step scaling function in quenched lattice QCD
The renormalisation group running of the quark mass is determined
non-perturbatively for a large range of scales, by computing the step scaling
function in the Schroedinger Functional formalism of quenched lattice QCD both
with and without O(a) improvement. A one-loop perturbative calculation of the
discretisation effects has been carried out for both the Wilson and the
Clover-improved actions and for a large number of lattice resolutions. The
non-perturbative computation yields continuum results which are regularisation
independent, thus providing convincing evidence for the uniqueness of the
continuum limit. As a byproduct, the ratio of the renormalisation group
invariant quark mass to the quark mass, renormalised at a hadronic scale, is
obtained with very high accuracy.Comment: 23 pages, 3 figures; minor changes, references adde
Berry curvature and Hall viscosities in an anisotropic Dirac semimetal
We investigate parity-odd nondissipative transport in an anisotropic Dirac semimetal in two spatial dimensions. The analysis is relevant for interacting electronic systems with merging Dirac points at charge neutrality. For such systems the dispersion relation is relativistic in one direction and nonrelativistic in the other. We give a proposal of how to calculate the Berry curvature for this system and use it to derive more than one odd viscosities, in contrast to rotationally invariant systems. We observe that in such a model the odd part of viscosity tensor is parametrized by two independent transport coefficients and one that is identically zero
VVV High Proper Motion Survey
Here we present survey of proper motion stars towards the Galactic Bulge and an adjacent plane region base on VISTA-VVV data. The searching method based on cross-matching photometric Ks-band CASU catalogs. The most interesting discoveries are shown.Peer reviewe
Deletions in the neuraminidase stalk region of H2N2 and H9N2 avian influenza virus subtypes do not affect postinfluenza secondary bacterial pneumonia
We investigated the synergism between influenza virus and Streptococcus pneumoniae, particularly the role of deletions in the stalk region of the neuraminidase (NA) of H2N2 and H9N2 avian influenza viruses. Deletions in the NA stalk (ΔNA) had no effect on NA activity or on the adherence of S. pneumoniae to virus-infected human alveolar epithelial (A549) and mouse lung adenoma (LA-4) cells, although it delayed virus elution from turkey red blood cells. Sequential S. pneumoniae infection of mice previously inoculated with isogenic recombinant H2N2 and H9N2 influenza viruses displayed severe pneumonia, elevated levels of intrapulmonary proinflammatory responses, and death. No differences between the WT and ΔNA mutant viruses were detected with respect to effects on postinfluenza pneumococcal pneumonia as measured by bacterial growth, lung inflammation, morbidity, mortality, and cytokine/chemokine concentrations. Differences were observed, however, in influenza virus-infected mice that were treated with oseltamivir prior to a challenge with S. pneumoniae. Under these circumstances, mice infected with ΔNA viruses were associated with a better prognosis following a secondary bacterial challenge. These data suggest that the H2N2 and H9N2 subtypes of avian influenza A viruses can contribute to secondary bacterial pneumonia and deletions in the NA stalk may modulate its outcome in the context of antiviral therapy. © 2012, American Society for Microbiology.Fil: Chockalingam, Ashok K.. University of Maryland; Estados UnidosFil: Hickman, Danielle. University of Maryland; Estados UnidosFil: Pena, Lindomar. University of Maryland; Estados UnidosFil: Ye, Jianqiang. University of Maryland; Estados UnidosFil: Ferrero, Andrea. University of Maryland; Estados UnidosFil: Echenique, Jose Ricardo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico CĂłrdoba. Centro de Investigaciones en BioquĂmica ClĂnica e InmunologĂa; ArgentinaFil: Chen, Hongjun. University of Maryland; Estados UnidosFil: Sutton, Troy. University of Maryland; Estados UnidosFil: Perez, Daniel R.. University of Maryland; Estados Unido
High U(1) charges in type IIB models and their F-theory lift
We construct models with U(1) gauge group and matter with charges up to 6, in the context of type IIB compactifications. We show explicitly that models with charges up to 4 can be derived from corresponding models in F-theory by applying the Sen weak coupling limit. We derive which type IIB models should be the limit of charge 5 and 6 F-theory models. Explicit six dimensional type IIB models with maximal charge 5 and 6 are constructed on an algebraic K3 surface that is the double cover of \u2102\u2119 2 . By using type IIB results we are also able to rediscover the F-theory charge 4 model in a straightforward way
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