229 research outputs found
Polarized and Unpolarized Lepton Pair Forward-backward Asymmetries in and Decays in Two Higgs Doublet Model
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 and
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 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
and 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
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 and decays within the factorization approach in QCD
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
and transitions, where and P and V are
pseudoscalar and vector mesons, are calculated in terms of the transition form
factors of the and . 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 Decays in QCD
The rare 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
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 structure via to transitions in QCD
We investigate the structure of the mesons via
analyzing the semileptonic , and
transitions in the framework of the three--point
QCD sum rules. We consider the meson in two ways, the pure
state and then as a mixture of two and 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 . The relevant form factors are calculated taking into
account the gluon condensate contributions. These form factors are numerically
obtained for case and plotted in terms of the unknown mixing angle
, when the meson are considered as mixture of two
and 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 .Comment: 33 Pages, 11 Figures and 5 Table
- …