10,927 research outputs found
Low-scale Supersymmetry from Inflation
We investigate an inflation model with the inflaton being identified with a
Higgs boson responsible for the breaking of U(1)B-L symmetry. We show that
supersymmetry must remain a good symmetry at scales one order of magnitude
below the inflation scale, in order for the inflation model to solve the
horizon and flatness problems, as well as to account for the observed density
perturbation. The upper bound on the soft supersymmetry breaking mass lies
between 1TeV and 10^3TeV. Interestingly, our finding opens up a possibility
that universes with the low-scale supersymmetry are realized by the
inflationary selection. Our inflation model has rich implications; non-thermal
leptogenesis naturally works, and the gravitino and moduli problems as well as
the moduli destabilization problem can be solved or ameliorated; the
standard-model higgs boson receives a sizable radiative correction if the
supersymmertry breaking takes a value on the high side ~10^3TeV.Comment: 23pages, 3 figures. v2: references adde
Pion photoproduction in a dynamical coupled-channel model
Pion photoproduction reactions are investigated in a dynamical
coupled-channel approach based on the Juelich pi-N model, which presently
includes the hadronic pi-N and eta-N stable channels as well as the pi-Delta,
sigma-N and rho-N effective channels. This model has been quite successful in
the description of pi-N to pi-N scattering for center-of-mass energies up to
1.9 GeV. The full pion photoproduction amplitude is constructed to satisfy the
generalized Ward-Takahashi identity and hence, it is fully gauge invariant. The
calculated differential cross sections and photon spin asymmetries up to 1.65
GeV center-of-mass energy for the reactions gamma p to pi+ n, gamma p to pi0 p
and gamma n to pi- p are in good agreement with the experimental data.Comment: Invited talk given at 12th International Conference on Meson-Nucleon
Physics and the Structure of the Nucleon (MENU2010), Williamsburg, USA, May
31-June 4 201
The phase and pole structure of the N*(1535) in piN-->piN and gammaN-->piN
The nature of some baryonic resonances is still an unresolved issue. The case
of the N*(1535) is particularly interesting in this respect due to the nearby
etaN threshold and interference with the N*(1650). The N*(1535) has been
described as a threshold effect, as a genuine 3-quark resonance, or as
dynamically generated from the interaction of the octet of baryons with the
octet of mesons. In the scheme of dynamical generation, predictions for the
interaction of the N*(1535) with the photon can be made. In this study, we
simultaneously analyze the role of the N*(1535) in the piN-->piN and
gammaN-->piN reactions and compare to the respective amplitudes from partial
wave analyses. This test is very sensitive to the meson-baryon components of
the N*(1535).Comment: 22 pages, 16 figures; updated to revised version accepted by EPJ
Smectic layer rotation by dc field in ferroelectric liquid crystal
This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in K. Nakayama, M. Ozaki, and K. Yoshino, Appl. Phys. Lett. 70, 2117 (1997) and may be found at https://doi.org/10.1063/1.118966
KRAS or BRAF mutation status is a useful predictor of sensitivity to MEK inhibition in ovarian cancer
This study examined the status of KRAS and BRAF mutations, in relation to extracellular signal-regulated protein kinase (ERK) activation in 58 ovarian carcinomas to clarify the clinicopathological and prognostic significance of KRAS/BRAF mutations. Somatic mutations of either KRAS or BRAF were identified in 12 (20.6%) out of 58 ovarian carcinomas. The frequency of KRAS/BRAF mutations in conventional serous high-grade carcinomas (4.0% : 1/25) was significantly lower than that in the other histological type (32.3% : 10/31). Phosphorylated ERK1/2 (p-ERK1/2) expression was identified in 18 (38.2%) out of 45 ovarian carcinomas. KRAS/BRAF mutation was significantly correlated with International Federation of Gynecology and Obstetrics (FIGO) stage I, II (P<0.001), and p-ERK1/2 (P<0.001). No significant correlations between KRAS/BRAF mutations or p-ERK1/2 expression and overall survival were found in patients with ovarian carcinoma treated with platinum and taxane chemotherapy (P=0.2460, P=0.9339, respectively). Next, to clarify the roles of ERK1/2 activation in ovarian cancers harbouring KRAS or BRAF mutations, we inactivated ERK1/2 in ovarian cancer cells using CI-1040. Cl-1040 is a compound that selectively inhibits MAP kinase kinase (MEK), an upstream regulator of ERK1/2, and thus prevents ERK1/2 activation. Profound growth inhibition and apoptosis were observed in CI-1040-treated cancer cells with mutations in either KRAS or BRAF in comparison with the ovarian cancer cells containing wild-type sequences. This was evident in both in vitro and in vivo studies. The findings in this study indicate that an activated ERK1/2 pathway is critical to tumour growth and survival of ovarian cancers with KRAS or BRAF mutations. Furthermore, they suggest that the CI-1040-induced phenotypes depend on the mutational status of KRAS and BRAF in ovarian cancers. Therefore, ovarian cancer patients with KRAS or BRAF mutations may benefit from CI-1040 treatment
Superfield Formulation for Non-Relativistic Chern-Simons-Matter Theory
We construct a superfield formulation for non-relativistic
Chern-Simons-Matter theories with manifest dynamical supersymmetry. By
eliminating all the auxiliary fields, we show that the simple action reduces to
the one obtained by taking non-relativistic limit from the relativistic
Chern-Simons-Matter theory proposed in the literature. As a further
application, we give a manifestly supersymmetric derivation of the
non-relativistic ABJM theory.Comment: 18 page
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