1,021 research outputs found

    The 2004 UTfit Collaboration Report on the Status of the Unitarity Triangle in the Standard Model

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    Using the latest determinations of several theoretical and experimental parameters, we update the Unitarity Triangle analysis in the Standard Model. The basic experimental constraints come from the measurements of |V_ub/V_cb|, Delta M_d, the lower limit on Delta M_s, epsilon_k, and the measurement of the phase of the B_d - anti B_d mixing amplitude through the time-dependent CP asymmetry in B^0 to J/psi K^0 decays. In addition, we consider the direct determination of alpha, gamma, 2 beta + gamma and cos(2 beta) from the measurements of new CP-violating quantities, recently performed at the B factories. We also discuss the opportunities offered by improving the precision of the various physical quantities entering in the determination of the Unitarity Triangle parameters. The results and the plots presented in this paper can also be found at http://www.utfit.org, where they are continuously updated with the newest experimental and theoretical results.Comment: 32 pages, 17 figures. High resolution figures and updates can be found at http://www.utfit.org v2: misprints correcte

    COLOROMETRIC DETERMINATION OF RANTIDINE HYDROCHLORIDE

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    A simple, precise and cost effective colorometric method have been developed for the estimation of Rantidine hydrochloride in its pharmaceutical formulations. RNH shows λmax at 520.0 nm. The drug follows the Beer-Lambert’s law. The method validated by following the analytical performance parameters suggested by the International Conference on Harmonization. All validation parameters were within the acceptable range. The developed methods were successfully applied to estimate the amount of RNH in pharmaceutical dosage form

    Flavor SU(3) analysis of charmless B meson decays to two pseudoscalar mesons

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    Global fits to charmless B --> PP decays in the framework of flavor SU(3) symmetry are updated and improved without reference to the \sin2\beta measured from the charmonium decay modes. Fit results directly constrain the (\bar\rho,\bar\eta) vertex of the unitarity triangle, and are used to predict the branching ratios and CP asymmetries of all decay modes, including those of the B_s system. Different schemes of SU(3) breaking in decay amplitude sizes are analyzed. The major breaking effect between strangeness-conserving and strangeness-changing decays can be accounted for by including a ratio of decay constants in tree and color-suppressed amplitudes. The possibility of having a new physics contribution to K \pi decays is also examined from the data fitting point of view.Comment: 22 pages and 2 figures; some comments and references added; more references added, version to appear in journa

    Forward-backward and isospin asymmetry for B -> K* l+ l- decay in the standard model and in supersymmetry

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    We discuss two dedicated observables in exclusive B -> K* l+ l- decay that can be used to study effects of physics beyond the standard model, namely the forward-backward asymmetry in the lepton spectrum and the isospin-asymmetry between decays of charged and neutral B mesons. We consider the region of large recoil-energy (i.e. small invariant mass of the lepton pair), and employ the QCD factorization approach to exclusive B meson decays. Sub-leading effects in the heavy quark mass expansion have been taken into account for the calculation of the isospin-asymmetry. We give predictions for decay asymmetries in the standard model, and its supersymmetric extension with minimal flavor violation, using parameter values allowed by current experimental constraints on B->X_s gamma decay.Comment: 21 pages, LaTeX with 6 figures, added reference

    APC-β-catenin-TCF signaling silences the intestinal guanylin-GUCY2C tumor suppressor axis.

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    Sporadic colorectal cancer initiates with mutations in APC or its degradation target β-catenin, producing TCF-dependent nuclear transcription driving tumorigenesis. The intestinal epithelial receptor, GUCY2C, with its canonical paracrine hormone guanylin, regulates homeostatic signaling along the crypt-surface axis opposing tumorigenesis. Here, we reveal that expression of the guanylin hormone, but not the GUCY2C receptor, is lost at the earliest stages of transformation in APC-dependent tumors in humans and mice. Hormone loss, which silences GUCY2C signaling, reflects transcriptional repression mediated by mutant APC-β-catenin-TCF programs in the nucleus. These studies support a pathophysiological model of intestinal tumorigenesis in which mutant APC-β-catenin-TCF transcriptional regulation eliminates guanylin expression at tumor initiation, silencing GUCY2C signaling which, in turn, dysregulates intestinal homeostatic mechanisms contributing to tumor progression. They expand the mechanistic paradigm for colorectal cancer from a disease of irreversible mutations in APC and β-catenin to one of guanylin hormone loss whose replacement, and reconstitution of GUCY2C signaling, could prevent tumorigenesis

    Direct CP Violation, Branching Ratios and Form Factors BπB \to \pi, BKB \to K in BB Decays

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    The BπB \to \pi and BKB \to K transitions involved in hadronic B decays are investigated in a phenomenological way through the framework of QCD factorization. By comparing our results with experimental branching ratios from the BELLE, BABAR and CLEO Collaborations for all the B decays including either a pion or a kaon, we propose boundaries for the transition form factors BπB \to \pi and BKB \to K depending on the CKM matrix element parameters ρ\rho and η\eta. From this analysis, the form factors required to reproduce the experimental data for branching ratios are FBπ=0.31±0.12F^{B \to \pi}= 0.31 \pm 0.12 and FBK=0.37±0.13F^{B \to K}= 0.37\pm 0.13. We calculate the direct CP violating asymmetry parameter, aCPa_{CP}, for Bπ+ππB \to \pi^{+} \pi^{-} \pi and Bπ+πKB \to \pi^{+} \pi^{-} K decays, in the case where ρω\rho-\omega mixing effects are taken into account. Based on these results, we find that the direct CP asymmetry for Bπ+ππB^{-} \to \pi^{+} \pi^{-} \pi^{-}, Bˉ0π+ππ0\bar{B}^{0} \to \pi^{+} \pi^{-} \pi^{0}, Bπ+πKB^{-} \to \pi^{+} \pi^{-} K^{-}, and Bˉ0π+πKˉ0\bar{B}^{0} \to \pi^{+} \pi^{-} \bar{K}^{0}, reaches its maximum when the invariant mass π+π\pi^{+} \pi^{-} is in the vicinity of the ω\omega meson mass. The inclusion of ρω\rho-\omega mixing provides an opportunity to erase, without ambiguity, the phase uncertainty mod(π)(\pi) in the determination of the CKM angles α\alpha in case of bub\to u and γ\gamma in case of bsb \to s.Comment: 74 pages, 15 figures, 8 tables. A few misprints corrected, two references adde

    Architecting in global software engineering

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    Cataloged from PDF version of article.This paper summarizes the results of the First Workshop on Architecting in Global Software Engineering (GSE), which was organized in conjunction with the 6th International Conference on Global Software Engineering (ICGSE 2011). The workshop aimed to bring together researchers and practitioners for defining and advancing the state-of-the-art and state-of-the practice in architecture design of global software development systems
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