Scalar and vector meson exchange in V->P0P0gamma decays

The scalar contributions to the radiative decays of light vector mesons into a pair of neutral pseudoscalars, $V\to P^0P^0\gamma$, are studied within the framework of the Linear Sigma Model. This model has the advantage of incorporating not only the scalar resonances in an explicit way but also the constraints required by chiral symmetry. The experimental data on $\phi\to\pi^0\pi^0\gamma$, $\phi\to\pi^0\eta\gamma$, $\rho\to\pi^0\pi^0\gamma$ and $\omega\to\pi^0\pi^0\gamma$ are satisfactorily accommodated in our framework. Theoretical predictions for $\phi\to K^0\bar K^0\gamma$, $\rho\to\pi^0\eta\gamma$, $\omega\to\pi^0\eta\gamma$ and the ratio $\phi\to f_0\gamma/a_0\gamma$ are also given.Comment: 42 pages, 11 figures. A new paragraph explaining the seminal contribution of Ref. [19] is adde

What will the first year of SNO show?

The ratio of the measured to the predicted standard model CC event rates in SNO will be 0.47 if no oscillations occur. The best-fit active oscillation predictions for the CC ratio are: 0.35-39 (MSW) and 0.38-42 (vacuum) (all for a 5 MeV energy threshold), typically about 20% less than the no-oscillation expectation. We calculate the predicted ratios for six active and sterile neutrino oscillation solutions allowed at 99% CL and determine the dependence of the ratios on energy threshold. If the high-energy anomaly observed by SuperKamiokande is due to an enhanced hep flux, MSW active solutions predict that out of a total of 5000 CC events above 5 MeV in SNO between 49 and 54 events will be observed above 13 MeV whereas only 19 events are expected for no-oscillations and a nominal standard hep flux.Comment: Phys Lett accepted. Editorial corrections. Related material and viewgraphs at http://www.sns.ias.edu/~jn

Actualización en radiología dental: Radiología convencional Vs digital

Desde su incorporación a la práctica odontológica la radiología digital ha experimentado un importante desarrollo. El continuo avance de las tecnologías en las que se sustenta ha dotado a estos sistemas de interesantes prestaciones que pueden facilitar el diagnóstico y manejo de imágenes radiográficas. Con estos avances la radiología digital ha despertado un interés creciente entre los profesionales de la odontología, especialmente durante los últimos años, en los que ha aumentado notoriamente tanto la cantidad de sistemas comercializados como el número de odontólogos que han decidido sustituir la radiología convencional por un sistema digital en sus clínicas. En esta revisión de la literatura se tratará de ofrecer una visión actualizada de los distintos sistemas disponibles en la actualidad, así como una comparativa entre ellos basada en estudios publicados recientemente. Since its appearance in dentistry, digital radiology has experienced a notorious development. A constant advance in the corresponding technologies has enhanced these digital systems with interesting features which may facilitate radiological diagnosis and image management. Due to these advances digital radiology has elicited a growing interest in dentistry. Specially during the last years there has been an increase both in the amount of available systems and in the number of dentists who have incorporated a digital system in their offices. This literature review aims to offer an updated view of the available systems and a comparison of them based in recent studies

Game of tops: trends in GBIFs community of users

Building on the development of Biodiversity Informatics, the Global Biodiversity Information Facility (GBIF) undertook the task of enabling access to the world¿s wealth of biodiversity data via the Internet. To date, GBIF has become, in many respects, the most extensive biodiversity information exchange infrastructure in the world, opening up a full range of possibilities for science

High energy solar neutrinos and p-wave contributions to ^3He(p,\nue^+)^4He

High energy solar neutrinos can come from the hep reaction ^3He(p,\nue^+)^4He with a large end point energy of 18.8 MeV. Understanding the hep reaction may be important for interpreting solar neutrino spectra. We calculate the contribution of the axial charge transition $^3P_0\to ^1S_0$ to the hep thermonuclear S factor using a one-body reaction model involving a nucleon moving in optical potentials. Our result is comparable to or larger than previous calculations of the s-wave Gamow Teller contribution. This indicates that the hep reaction may have p-wave strength leading to an enhancement of the S factor.Comment: 4 pages, 1 ps figure, very minor changes, Phys. Rev. C in pres

Recombinant monovalent llama-derived antibody fragments (VHH) to rotavirus VP6 protect neonatal gnotobiotic piglets against human rotavirus-induced diarrhea

Group A Rotavirus (RVA) is the leading cause of severe diarrhea in children. The aims of the present study were to determine the neutralizing activity of VP6-specific llama-derived single domain nanoantibodies (VHH nanoAbs) against different RVA strains in vitro and to evaluate the ability of G6P[1] VP6-specific llama-derived single domain nanoantibodies (VHH) to protect against human rotavirus in gnotobiotic (Gn) piglets experimentally inoculated with virulent Wa G1P[8] rotavirus. Supplementation of the daily milk diet with 3B2 VHH clone produced using a baculovirus vector expression system (final ELISA antibody -Ab- titer of 4096; virus neutralization -VN- titer of 256) for 9 days conferred full protection against rotavirus associated diarrhea and significantly reduced virus shedding. The administration of comparable levels of porcine IgG Abs only protected 4 out of 6 of the animals from human RVA diarrhea but significantly reduced virus shedding. In contrast, G6P[1]-VP6 rotavirus-specific IgY Abs purified from eggs of hyperimmunized hens failed to protect piglets against human RVA-induced diarrhea or virus shedding when administering similar quantities of Abs. The oral administration of VHH nanoAb neither interfered with the host's isotype profiles of the Ab secreting cell responses to rotavirus, nor induced detectable host Ab responses to the treatment in serum or intestinal contents. This study shows that the oral administration of rotavirus VP6-VHH nanoAb is a broadly reactive and effective treatment against rotavirus-induced diarrhea in neonatal pigs. Our findings highlight the potential value of a broad neutralizing VP6-specific VHH nanoAb as a treatment that can complement or be used as an alternative to the current strain-specific RVA vaccines. Nanobodies could also be scaled-up to develop pediatric medication or functional food like infant milk formulas that might help treat RVA diarrhea.Fil: Vega, Celina Guadalupe. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bok, Marina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vlasova, Anastasia N.. Ohio State University; Estados UnidosFil: Chattha, Kuldeep S.. Ohio State University; Estados UnidosFil: Gómez Sebastián, Silvia. Universidad Politécnica de Madrid; EspañaFil: Nuñez, Carmen. Universidad Politécnica de Madrid; EspañaFil: Alvarado, Carmen. Universidad Politécnica de Madrid; EspañaFil: Lasa, Rodrigo. Universidad Politécnica de Madrid; EspañaFil: Escribano, José M.. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. Departamento Mejora Genética y Biotecnología; EspañaFil: Garaicoechea, Lorena Laura. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fernández, Fernando. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; ArgentinaFil: Bok, Karin. National Institutes of Health; Estados UnidosFil: Wigdorovitz, Andrés. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Saif, Linda J.. Ohio State University; Estados UnidosFil: Parreño, Gladys Viviana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Limits on the Dipole Moments of the τ\tau-Lepton via the Process $e^{+}e^{-}\to \tau^+ \tau^- \gamma in a Left-Right Symmetric Model

Limits on the anomalous magnetic moment and the electric dipole moment of the $\tau$ lepton are calculated through the reaction $e^{+}e^{-}\to \tau^+ \tau^- \gamma$ at the $Z_1$-pole and in the framework of a left-right symmetric model. The results are based on the recent data reported by the L3 Collaboration at CERN LEP. Due to the stringent limit of the model mixing angle $\phi$, the effect of this angle on the dipole moments is quite small.Comment: 15 pages, 3 figure

Searching for Anomalous Weak Couplings of Heavy Flavors at the SLC and LEP

The existence of anomalous electric($\tilde \kappa$) and/or magnetic($\kappa$) dipole moment couplings between the heavy flavor fermions ($c,b,\tau$) and the $Z$ boson can cause significant shifts in the values of several electroweak observables currently being probed at both the SLC and LEP. Using the good agreement between existing data and the predictions of the Standard Model we obtain strict bounds on the possible strength of these new interactions for all of the heavy flavors. The decay $Z\rightarrow b\bar b$, however, provides some possible hint of new physics. The corresponding anomalous couplings of $\tau$'s to photons is briefly examined.Comment: 21 pages, 14 figs(available on request), LaTex, SLAC-PUB-667