229 research outputs found

    Polarized and Unpolarized Lepton Pair Forward-backward Asymmetries in BK0(1430)+\overline{B}\rightarrow \overline{K}_{0}^{*}(1430) \ell^+\ell^- and BK+\overline{B}\rightarrow \overline{K} \ell^+\ell^- Decays in Two Higgs Doublet Model

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    In this paper we shall focus on the effects of concrete models such as SM and Model III of 2HDM on the polarized and unpolarized forward-backward asymmetries of BK0(1430)+\overline{B}\rightarrow \overline{K}_0^{*}(1430) \ell^+\ell^- and BK+\overline{B}\rightarrow \overline{K} \ell^+\ell^- decays. The obtained results of these decay modes are compared to each other. Also, we obtain the minimum required number of events for detecting each asymmetry and compare them with the number of produced BBˉB\bar{B} pairs at the LHC or supposed to be produced at the Super-LHC. At the end, we conclude that the study of these asymmetries for BK0(1430)+\overline{B}\rightarrow \overline{K}_0^*(1430) \ell^+\ell^- and BK+\overline{B}\rightarrow \overline{K} \ell^+\ell^- processes are very effective tools for establishing new physics in the future B-physics experiments

    Interaction between ketoconazole, amphotericin B and terbinafin and three diazenumdiolates in concomitant uses against some fugal species

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    A checkerboard broth microdilution method was performed to investigate the in vitro antifungal activities of three diazeniumdiolates derivatives (DETA/NO, DPTA/NO, DEA/NO) alone and in combination with ketoconazole, amphotricin B or terbinafine against five Candida species, Cryptococcus neoformance and four dermatophyte strains. MICs and MLCs were recorded, and synergy was calculated by using fractional inhibitory and fractional lethal concentration index. DETA/NO with a half-life of 57h at 25°C showed antifungal activity against all tested dermatophyte species (MIC 0.150 to 2.5mg/ml), DPTA/NO with a half life of 3h at 37°C showed antifungal activity against five species of Candida and Cryptococcus neoformans, and DEA/NO with a half life of 2 min at 37°C and 16 min at 25° C did not show antifungal activity against tested strains. Combinations of DPTA-NO with either ketoconazole or amphotericin B were either synergistic or indifferent for all tested strain of Candida and Cryptococcus neoformance. DETA/NO was unable to enhance the antifungal activity of terbinafine against dermatophyte strains. Even where no synergistic activity was achieved, there was still a decrease in the MIC of one or both drugs which were used in combination. Antagonism was observed between terbinafine and DETA-NO against Trichophyton rubrum. Our result suggests that DETA/NO and DPTA/NO may be useful for development of new therapeutic strategies for treatment of dermatophyte and Candida infections. Clinical studies are warranted to elucidate the potential utility of these combination therapies

    Analysis of the BqDq(Dq)PB_q\to D_q(D_q^*) P and BqDq(Dq)VB_q\to D_q(D_q^*) V decays within the factorization approach in QCD

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    Using the factorization approach and considering the contributions of the current-current, QCD penguin and electroweak penguin operators at the leading approximation, the decay amplitudes and decay widths of BqDq(Dq)PB_q\to D_q(D_q^*) P and BqDq(Dq)VB_q\to D_q(D_q^*) V transitions, where q=u,d,sq=u,d,s and P and V are pseudoscalar and vector mesons, are calculated in terms of the transition form factors of the BqDqB_q\to D_{q} and BqDqB_q\to D^{*}_{q}. Having computed those form factors in three-point QCD sum rules, the branching fraction for these decays are also evaluated. A comparison of our results with the predictions of the perturbative QCD as well as the existing experimental data is presented.Comment: 18 Pages and 9 Table

    Analysis of the Rare BcDs,dl+lB_c \to D_{s,d}^{*} l^+ l^- Decays in QCD

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    The rare BcDs,dl+lB_c \to D_{s,d}^{*} l^+ l^- decays are investigated in the framework of the three point QCD sum rules approach. Considering the gluon condensate corrections to the correlation function, the form factors relevant to these transitions are calculated. The total decay width and branching ratio for these decays are also evaluated. The results for the branching ratios are in good agreement with the quark models.Comment: 20 Pages, 2 Figures and 5 Table

    Expression of efflux pumps and fatty acid activator one genes in azole resistant Candida glabrata isolated from immunocompromised patients

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    Acquired azole resistance in opportunistic fungi causes severe clinical problems in immunosuppressed individuals. This study investigated the molecular mechanisms of azole resistance in clinical isolates of Candida glabrata. Six unmatched strains were obtained from an epidemiological survey of candidiasis in immunocompromised hosts that included azole and amphotericin B susceptible and azole resistant clinical isolates. Candida glabrata CBS 138 was used as reference strain. Antifungal susceptibility testing of clinical isolates was evaluated using Clinical and Laboratory Standards Institute (CLSI) methods. Complementary DNA-Amplified Fragment Length Polymorphism (cDNA-AFLP) technology, semiquantitative RT-PCR, and sequencing were employed for identification of potential genes involved in azole resistance. Candida glabrata Candida drug resistance 1 (CgCDR1) and Candida glabrata Candida drug resistance 2 (CgCDR2) genes, which encode for multidrug transporters, were found to be upregulated in azole-resistant isolates (�2-fold). Fatty acid activator 1 (FAA1) gene, belonging to Acyl-CoA synthetases, showed expression in resistant isolates �2-fold that of the susceptible isolates and the reference strain. This study revealed overexpression of the CgCDR1, CgCDR2, and FAA1 genes affecting biological pathways, small hydrophobic compounds transport, and lipid metabolism in the resistant clinical C.glabrata isolates. © 2016 Tehran University of Medical Sciences. All rights reserved

    Investigation of the Ds1D_{s1} structure via BcB_c to Ds1l+l/ννˉD_{s1} l^+l^-/\nu\bar\nu transitions in QCD

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    We investigate the structure of the Ds1(2460,2536)(JP=1+)D_{s1}(2460,2536) (J^P=1^+) mesons via analyzing the semileptonic BcDs1l+lB_{c}\to D_{s1}l^+l^-, l=τ,μ,el=\tau, \mu, e and BcDs1ννˉB_{c}\to D_{s1}\nu\bar{\nu} transitions in the framework of the three--point QCD sum rules. We consider the Ds1D_{s1} meson in two ways, the pure csˉ>|c\bar{s}> state and then as a mixture of two 3P1>|^3P_1> and 1P1>|^1P_1> states. Such type rare transitions take place at loop level by electroweak penguin and weak box diagrams in the standard model via the flavor changing neutral current transition of bsb \to s. The relevant form factors are calculated taking into account the gluon condensate contributions. These form factors are numerically obtained for csˉ>|c\bar s> case and plotted in terms of the unknown mixing angle θs\theta_s, when the Ds1D_{s1} meson are considered as mixture of two 3P1>|^3P_1> and 1P1>|^1P_1> states. The obtained results for the form factors are used to evaluate the decay rates and branching ratios. Any future experimental measurement on these form factors as well as decay rates and branching fractions and their comparison with the obtained results in the present work can give considerable information about the structure of this meson and the mixing angle θs\theta_s.Comment: 33 Pages, 11 Figures and 5 Table
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