9,206 research outputs found
Implications for new physics from and
We have analyzed the puzzle in three kinds of
models beyond the standard model (SM). It is shown that the minimal flavor
violation (MFV) models, the minimal supersymmetric standard model (MSSM), and
the two Higgs doublet models (2HDM) I and II can not give an explanation of the
puzzle within experimental bounds and the
model III 2HDM can explain the puzzle without a conflict with other
experimental measurements. If the constraint on from is not
imposed, for all kinds of insertions considered there are regions of parameter
space, where the scalar quark mass is larger (much larger) than the gluino mass
in the case of LR or RL (LL or RR), in which the puzzle can be resolved within
experimental bounds.Comment: 7 pages, 3 eps files. Add some more explicit analysis version
appeared in PL
Dietary Blueberry and Bifidobacteria Attenuate Nonalcoholic Fatty Liver Disease in Rats by Affecting SIRT1-Mediated Signaling Pathway
NAFLD model rats were established and divided into NAFLD model (MG group), SIRT1 RNAi (SI group), blueberry juice (BJ group), blueberry juice + bifidobacteria (BJB group), blueberry juice + SIRT1 RNAi (BJSI group), and blueberry juice + bifidobacteria + SIRT1 RNAi groups (BJBSI group). A group with normal rats was a control group (CG). BJB group ameliorated NAFLD, which was better than BJ group (P<0.05). The lipid accumulation was lower in CG, BJ, and BJB groups than that in MG, SI, BJSI, and BJBSI groups (P<0.05). The levels of SIRT1 and PPAR-α were higher in CG, BJ, and BJB groups than those in MG, SI, BJSI, and BJBSI groups (P<0.05). The levels of SREBP-1c were lower in CG, BJ, and BJB groups than those in MG, SI, BJSI, and BJBSI groups (P<0.05). The biochemical indexes SOD, GSH, and HDL-c were improved from CG to BJB group (P<0.05). Inversely, the levels of AST and ALT, TG, TC, LDL-c, and MDA were decreased from CG to BJB group (P<0.05). These changes enhance antioxidative capability and biochemical index of rats. Blueberry juice and bifidobacteria improve NAFLD by activating SIRTI-mediating signaling pathway
Clinical and radiological presentations of pelvic parachordoma
Parachordoma is an extremely rare entity and there are only about 50 to 60 cases reported, in which there is only one definite pelvic parachordoma. We present a huge well-defined presacral tumor in a 48-year-old woman who has the symptoms of lower abdominal pain and difficulty in defecating. Radiological findings of the tumor on computed tomography and magnetic resonance imaging are described in detail. The reasons why we report the case are because the patient has rare clinical symptoms and because this is the second pelvic parachordoma. Then, we summarize the radiological features of parachordoma based on our study and the review of literature
Transmission resonance in a composite plasmonic structure
The design, fabrication, and optical properties of a composite plasmonic
structure, a two-dimentional array of split-ring resonators inserted into
periodic square holes of a metal film, have been reported. A new type of
transmission resonance, which makes a significant difference from the
conventional peaks, has been suggested both theoretically and experimentally.
To understand this effect, a mechanism of ring- resonance induced dipole
emission is proposed.Comment: 14 pages, 4 figure
Singlet-triplet transitions in highly correlated nanowire quantum dots
We consider a quantum dot embedded in a three-dimensional nanowire with
tunable aspect ratio a. A configuration interaction theory is developed to
calculate the energy spectra of the finite 1D quantum dot systems charged with
two electrons in the presence of magnetic fields B along the wire axis.
Fruitful singlet-triplet transition behaviors are revealed and explained in
terms of the competing exchange interaction, correlation interaction, and spin
Zeeman energy. In the high aspect ratio regime, the singlet-triplet transitions
are shown designable by tuning the parameters a and B. The transitions also
manifest the highly correlated nature of long nanowire quantum dots.Comment: 4 pages, 4 figure
Neutral Higgs boson contributions to CP asymmetry of in MSSM
We have studied the neutral Higgs boson (NHB) contributions to the pure
penguin process in MSSM with middle and large (say,
8). We show that the order hadronic matrix elements of NHB
induced operators can make sizable effects on both the branch ratio and time
dependent CP asymmetry . Under the all relevant experimental
constraints, the Higgs mediated contributions to alone can provide
a significant deviation from SM and, in particular, lead to a negative which is reported by BaBar and Belle.Comment: 7 pages and 6 figure
CP asymmetries in and in MSSM
We study the and B\to \ep K_S decays in MSSM by calculating
hadronic matrix elements of operators with QCD factorization approach and
including neutral Higgs boson (NHB) contributions. We calculate the Wilson
coefficients of operators including the new operators which are induced by NHB
penguins at LO using the MIA with double insertions. We calculate the
order hadronic matrix elements of the new operators for and . It is shown that the recent experimental
results on the time-dependent CP asymmetries in and B\to \ep
K_S, is negative and is positive, which can
not be explained in SM, can be explained in MSSM if there are flavor
non-diagonal squark mass matrix elements of 2nd and 3rd generations whose size
satisfies all relevant constraints from known experiments (, etc.). In
particular, we find that one can explain the experimental results with a flavor
non-diagonal mass insertion of any chirality when corrections of
hadronic matrix elements of operators are included, in contrast with the claim
in the literature. At the same time, the branching ratios for the two decays
can also be in agreement with experimental measurements.Comment: 21 pages, 23 figures. Some changes have been made, which include
comments on contributions to and from RR and
RL insertion and some typing error
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