Electron Spin Resonance In Amorphous Silicon Doped With Gd

ESR experiments on Gd impurities in amorphous silicon between liquid-He and room temperatures show three resonances which could be ascribed to paramagnetic dangling bonds (g=2.00550.0005), to Gd S7/28 states (g=1.9970.005), and to a new paramagnetic center (g=2.100.05) associated with the presence of Gd atoms. For low-Gd-concentration samples the intensity of the resonance due to dangling bonds decreases as the Gd concentration increases and the intensity of the new paramagnetic center is found to increase with increasing temperature. These results indicate, as we recently found for other rare-earthelement impurities in a-Si, that a fraction of the Gd atoms act as acceptor impurities with associated loosely bound holes in the a-Si valence-band tail which are responsible for the resonance of the new paramagnetic center observed at a g value of 2.100.05. © 1989 The American Physical Society.39128398840

New Paramagnetic Center In Amorphous Silicon Doped With Rare-earth Elements

A new paramagnetic center associated with rare earths (RE) (La, Ce, Pr, Nd, Gd, Er, and Lu) in amorphous silicon is reported. It is shown that RE impurities are incorporated in a-Si and that the density of paramagnetic dangling bonds decreases as a consequence of the presence of these impurities. An interpretation in terms of RE 6s orbitals and crystal-field-split 5d orbital hybridization suggests that the RE behaves as an acceptor impurity with an associated hole in the a-Si valence-band tail, which is responsible for the observed resonance at a g value of 2.100.01. © 1989 The American Physical Society.3942860286

Evaluation of metabolic and biochemical blood parameters in lactating cows with Cystic Ovarian Disease

The aim of the study was to determine and evaluate different blood parameters associated to energetic, protein, mineral and liver metabolic processes together with productive and reproductive parameters in dairy cows of Santa Fe province (Argentina) that were diagnosed with cystic ovarian disease (COD). Lactating Argentine Holstein cows from five dairy herds with spontaneous COD (n= 80) diagnosed by ultrasound and control cows (n= 124) were included in the study. Blood samples were obtained from all cows to determine serum concentrations of: growth hormone, insulin-like growth factor (IGF-1), insulin, aspartate aminotransferase, alkalin phosphatase, gamma glutamiltransferase, albumin, total proteins, albumin: globulin ratio, total and direct bilirrubin, ?-hidroxibutirate, colesterol, glucose, urea, creatinin, calcium, phosphorus and magnesium. Serum concentrations of insulin and IGF-1 were lower (P<0.05) in COD than control cows. No significant differences among groups were observed in any other variables studied, however, the calving to conception interval was higher in cows with COD compared to controls. These results allowed us to conclude that there would be an association between blood concentrations of IGF-1 and insulin and COD that, ultimately, compromise the reproductive performance of the cow.Fil: Cattaneo, L. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Cátedra de Teriogenología. Santa Fe, ArgentinaFil: Barberis, F.C. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Cátedra de Teriogenología. Santa Fe, ArgentinaFil: Stangaferro, M.L. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Cátedra de Teriogenología. Santa Fe, ArgentinaFil: Signorini, M.L. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela. ArgentinaFil: Signorini, M.L. CONICET. ArgentinaFil: Ruiz, M.F. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Hospital de Salud Animal. Santa Fe, ArgentinaFil: Zimmermann, R. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Hospital de Salud Animal. Santa Fe, ArgentinaFil: Bo, G.A. Instituto de Reproducción Animal Córdoba (IRAC). ArgentinaFil: Hein, G.J. CONICET - Universidad Nacional del Litoral. Instituto de Ciencias Veterinarias del Litoral (ICiVet-Litoral). Esperanza, ArgentinaFil: Ortega, H.H. CONICET - Universidad Nacional del Litoral. Instituto de Ciencias Veterinarias del Litoral (ICiVet-Litoral). Esperanza, ArgentinaEl objetivo de este trabajo fue determinar y evaluar indicadores bioquímicos sanguíneos asociados a procesos metabólicos energéticos, proteicos, minerales y de funcionalidad hepática, junto con parámetros productivos y reproductivos en vacas lecheras que fueron diagnosticadas con enfermedad quística ovárica (COD) y controles. Se emplearon vacas Holando Argentino en lactancia de 5 rebaños de la provincia de Santa Fe (Argentina) que presentaban COD (n= 80) diagnosticada mediante ultrasonografía y controles clínicamente sanas (n= 124). De las vacas se obtuvo sangre coccígea para determinar las concentraciones séricas de las hormonas de crecimiento (GH), factor de crecimiento similar a la insulina-1 (IGF-1) e insulina, la actividad sérica de AST, FA, GGT y las concentraciones séricas de albúmina, proteínas totales, relación albúmina: globulinas, bilirrubina total y directa, ?-hidroxibutirato, colesterol, glucosa, urea, creatinina, calcio, fósforo y magnesio. Las concentraciones séricas de insulina e IGF-1 fueron menores (P<0,05) en las vacas con COD que en las controles. No se observaron diferencias significativas (P>0,05) entre ambos grupos en las demás variables séricas y productivas evaluadas, sin embargo, el intervalo parto-concepción fue mayor en vacas que presentaron COD. Los resultados nos permitieron concluir que habría una asociación entre los valores séricos de IGF-1 e insulina y la COD, y que ésta comprometería el futuro reproductivo de las vacas

A Study of J/psi-->gamma gamma V(rho,phi) Decays with the BESII Detector

Using a sample of $58\times 10^6$ $J/\psi$ events collected with the BESII detector, radiative decays $J/\psi\to\gamma\gamma V$, where $V=\rho$ or $\phi$, are studied. A resonance around 1420 MeV/c$^2$ (X(1424)) is observed in the $\gamma\rho$ mass spectrum. Its mass and width are measured to be $1424\pm 10(stat)\pm 11(sys)$ MeV/c$^2$ and $101.0\pm 8.8 \pm 8.8$ MeV/c$^2$, respectively, and its branching ratio $B(J/\psi\to \gamma X(1424)\to \gamma \gamma \rho)$ is determined to be $(1.07\pm0.17 \pm 0.11)\times 10^{-4}$. A search for $X(1424)\to \gamma\phi$ yields a 95% C.L. upper limit $B(J/\psi\to \gamma X(1424)\to \gamma\gamma \phi) < 0.82 \times 10^{-4}$.Comment: 10 pages, 5 figures, submitted to PL

Measurement of the View the tt production cross-section using eμ events with b-tagged jets in pp collisions at √s = 13 TeV with the ATLAS detector

This paper describes a measurement of the inclusive top quark pair production cross-section (σtt¯) with a data sample of 3.2 fb−1 of proton–proton collisions at a centre-of-mass energy of √s = 13 TeV, collected in 2015 by the ATLAS detector at the LHC. This measurement uses events with an opposite-charge electron–muon pair in the final state. Jets containing b-quarks are tagged using an algorithm based on track impact parameters and reconstructed secondary vertices. The numbers of events with exactly one and exactly two b-tagged jets are counted and used to determine simultaneously σtt¯ and the efficiency to reconstruct and b-tag a jet from a top quark decay, thereby minimising the associated systematic uncertainties. The cross-section is measured to be: σtt¯ = 818 ± 8 (stat) ± 27 (syst) ± 19 (lumi) ± 12 (beam) pb, where the four uncertainties arise from data statistics, experimental and theoretical systematic effects, the integrated luminosity and the LHC beam energy, giving a total relative uncertainty of 4.4%. The result is consistent with theoretical QCD calculations at next-to-next-to-leading order. A fiducial measurement corresponding to the experimental acceptance of the leptons is also presented

Search for TeV-scale gravity signatures in high-mass final states with leptons and jets with the ATLAS detector at sqrt [ s ] = 13TeV

A search for physics beyond the Standard Model, in final states with at least one high transverse momentum charged lepton (electron or muon) and two additional high transverse momentum leptons or jets, is performed using 3.2 fb−1 of proton–proton collision data recorded by the ATLAS detector at the Large Hadron Collider in 2015 at √s = 13 TeV. The upper end of the distribution of the scalar sum of the transverse momenta of leptons and jets is sensitive to the production of high-mass objects. No excess of events beyond Standard Model predictions is observed. Exclusion limits are set for models of microscopic black holes with two to six extra dimensions

Search for strong gravity in multijet final states produced in pp collisions at √s=13 TeV using the ATLAS detector at the LHC

A search is conducted for new physics in multijet final states using 3.6 inverse femtobarns of data from proton-proton collisions at √s = 13TeV taken at the CERN Large Hadron Collider with the ATLAS detector. Events are selected containing at least three jets with scalar sum of jet transverse momenta (HT) greater than 1TeV. No excess is seen at large HT and limits are presented on new physics: models which produce final states containing at least three jets and having cross sections larger than 1.6 fb with HT > 5.8 TeV are excluded. Limits are also given in terms of new physics models of strong gravity that hypothesize additional space-time dimensions

Operation and performance of the ATLAS semiconductor tracker

The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74±0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, δ-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations

Measurement of the correlation between flow harmonics of different order in lead-lead collisions at √sNN = 2.76 TeV with the ATLAS detector

Correlations between the elliptic or triangular flow coefficients vm (m=2 or 3) and other flow harmonics vn (n=2 to 5) are measured using √sNN=2.76 TeV Pb+Pb collision data collected in 2010 by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 7 μb−1. The vm−vn correlations are measured in midrapidity as a function of centrality, and, for events within the same centrality interval, as a function of event ellipticity or triangularity defined in a forward rapidity region. For events within the same centrality interval, v3 is found to be anticorrelated with v2 and this anticorrelation is consistent with similar anticorrelations between the corresponding eccentricities, ε2 and ε3. However, it is observed that v4 increases strongly with v2, and v5 increases strongly with both v2 and v3. The trend and strength of the vm−vn correlations for n=4 and 5 are found to disagree with εm−εn correlations predicted by initial-geometry models. Instead, these correlations are found to be consistent with the combined effects of a linear contribution to vn and a nonlinear term that is a function of v22 or of v2v3, as predicted by hydrodynamic models. A simple two-component fit is used to separate these two contributions. The extracted linear and nonlinear contributions to v4 and v5 are found to be consistent with previously measured event-plane correlations