167,425 research outputs found
Semileptonic Decays to and in Bethe-Salpeter Method
Using the relativistic Bethe-Salpeter method, the electron energy spectrum
and the semileptonic decay widths of and
are calculated. We obtained large branching
ratios, and , which can be easily detected in the future
experiment.Comment: 3 pages, 3 figures
Electric and Magnetic Excitation of Coherent Magnetic Plasmon Waves in a One-dimensional Meta-chain
A one-dimensional diatomic meta-chain with equal-size holes and
different-length slits is designed. Broadband coherent magnetic plasmon waves
(MPW) are formed in such a system, excited by both the electric resonance in
the slits and the magnetic resonance in the holes in a wide range of incidence
angles (00-400) and broad frequency bands (200-230 THz). The dispersion
properties of the MPW measured in our experiments agree with the theoretical
calculation based on the Lagrange model. The coherent MPWs reported in this
paper may have applications in subwavelength integrated nanocircuits
Stability of BTZ black strings
We study the dynamical stability of the BTZ black string against fermonic and
gravitational perturbations. The BTZ black string is not always stable against
these perturbations. There exist threshold values for related to the
compactification of the extra dimension for fermonic perturbation, scalar part
of the gravitational perturbation and the tensor perturbation, respectively.
Above the threshold values, perturbations are stable; while below these
thresholds, perturbations can be unstable. We find that this non-trivial
stability behavior qualitatively agrees with that predicted by a
thermodynamical argument, showing that the BTZ black string phase is not the
privileged stable phase.Comment: 9 pages, revised version to appear in Phys. Rev.
The transcription factors Egr2 and Egr3 are essential for the control of inflammation and antigen-induced proliferation of B and T cells
This article is available open access under a Creative Commons license (http://creativecommons.org/licenses/by-nc-nd/3.0/). Copyright @ 2012 Elsevier Inc.Lymphocytes provide optimal responses against pathogens with minimal inflammatory pathology. However, the intrinsic mechanisms regulating these responses are unknown. Here, we report that deletion of both transcription factors Egr2 and Egr3 in lymphocytes resulted in a lethal autoimmune syndrome with excessive serum proinflammatory cytokines but also impaired antigen receptor-induced proliferation of B and T cells. Egr2- and Egr3-defective B and T cells had hyperactive signal transducer and activator of transcription-1 (STAT1) and STAT3 while antigen receptor-induced activation of transcription factor AP-1 was severely impaired. We discovered that Egr2 and/or Egr3 directly induced expression of suppressor of cytokine signaling-1 (SOCS1) and SOCS3, inhibitors of STAT1 and STAT3, and also blocked the function of Batf, an AP-1 inhibitor, in B and T cells. Thus, Egr2 and Egr3 regulate B and T cell function in adaptive immune responses and homeostasis by promoting antigen receptor signaling and controlling inflammation.Arthritis Research U
Identification of the white dwarf companion to millisecond pulsar J2317+1439
We report identification of the optical counterpart to the companion of the
millisecond pulsar J2317+1439. At the timing position of the pulsar, we find an
object with , and . The
magnitudes and colors of the object are consistent with it being a white dwarf.
By comparing with white dwarf cooling models, we estimate that it has a mass of
M, an effective temperature of
K and a cooling age of Gyr. Combining our
results with published constraints on the orbital parameters obtained through
pulsar timing, we estimate the pulsar mass to be
M. Although the constraint on the pulsar mass is still weak, there is
a significant possibility that the pulsar could be more massive than two solar
mass.Comment: 7 pages, 6 figures, accepted for publication in Ap
Coherent magnetic plasmon modes in a contacting gold nano-sphere chain on a gold Slab
A coupled magnetic resonator waveguide, composed of a contacting gold
nanosphere chain on a gold slab, is proposed and investigated. A broadband
coherent magnetic plasmon mode can be excited in this one dimensional
nanostructure. By employing the Lagrangian formalism and the Fourier transform
method, the dispersion properties of the wave vector and group velocity of the
magnetic plasmon mode are investigated. Small group velocity can be obtained
from this system which can be applied as subwavelength slow wave waveguides.Comment: 11pages, 5 figures, This work is published at Optics Express 19,
23782 (2011
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