7,092 research outputs found
Results in Kalb-Ramond field localization and resonances on deformed branes
We make an analysis about several aspects of localization of the Kalb-Ramond
gauge field in a specific four dimensional AdS membrane embedded in a five
dimensional space-time. The membrane is generated from a deformation of the
potential and belongs to a new class of defect solutions. In
this context we find resonance structures in the analysis of massive modes. The
study of deformed defects is important because they contain internal structures
and these may have implications to the way the background space-time is
constructed and the way its curvature behaves. The main objective here is to
observe the contributions of the deformation procedure to the resonances and
the well known field localization methods.Comment: 6 pages, 7 figures, Latex with EPL macr
Fermion localization on asymmetric two-field thick branes
In this paper we investigate the localization of fermions on asymmetric thick
branes generated by two scalars and . In order to trap fermions on
the asymmetric branes with kink-like warp factors, the couplings with the
background scalars are introduced, where
is a function of and . We find that the coupling
do not support the localization of 4-dimensional
fermions on the branes. While, for the case
, which is the kink-fermion
coupling corresponding to one-scalar-generated brane scenarios, the zero mode
of left-handed fermions could be trapped on the branes under some conditions.Comment: v2: 11 pages, 4 figures, accepted by CQ
Location Based Indoor and Outdoor Lightweight Activity Recognition System
In intelligent environments one of the most relevant information that can be gathered about users is their location. Their position can be easily captured without the need for a large infrastructure through devices such as smartphones or smartwatches that we easily carry around in our daily life, providing new opportunities and services in the field of pervasive computing and sensing. Location data can be very useful to infer additional information in some cases such as elderly or sick care, where inferring additional information such as the activities or types of activities they perform can provide daily indicators about their behavior and habits. To do so, we present a system able to infer user activities in indoor and outdoor environments using Global Positioning System (GPS) data together with open data sources such as OpenStreetMaps (OSM) to analyse the user’s daily activities, requiring a minimal infrastructure
Scalar-Kinetic Branes
This work tries to find out thick brane solutions in braneworld scenarios
described by a real scalar field in the presence of a scalar-kinetic term
with a single extra dimension, where
stands for the standard kinetic term and
. We mainly consider bent branes, namely de Sitter and Anti-de
Sitter four-dimensional slices. The solutions of a flat brane are obtained when
taking the four-dimensional cosmological constant .
When the parameter , these solutions turn to those of the standard
scenario. The localization and spectrum of graviton on these branes are also
analyzed.Comment: 10 pages, no figures, accepted by EP
Pair production of the heavy leptons in future high energy linear e^{+}e^{-} colliders
The littlest Higgs model with T-parity predicts the existence of the T-odd
particles, which can only be produced in pair. We consider pair production of
the T-odd leptons in future high energy linear collider ().
Our numerical results show that, as long as the T-odd leptons are not too
heavy, they can be copiously produced and their possible signals might be
detected via the processes in future
experiments.Comment: Discussions added, typos and references correcte
Probing the lightest new gauge boson in the littlest Higgs model via the processes at the ILC
The neutral gauge boson with the mass of hundreds GeV, is the lightest
particle predicted by the littlest Higgs(LH) model, and such particle should be
the first signal of the LH model at the planed ILC if it exists indeed. In this
paper, we study some processes of the production associated with the
fermion pair at the ILC, i.e., . The studies
show that the most promising processes to detect among are , and they can
produce the sufficient signals in most parameter space preferred by the
electroweak precision data at the ILC. On the other hand, the signal produced
via the certain decay modes is typical and such signal can be easily
identified from the SM background. Therefore, , the lightest gauge boson
in the LH model would be detectable at the photon collider realized at the ILC.Comment: 12 pages, 4 figure
LD Motif Recognition by Talin: Structure of the Talin-DLC1 Complex
Cell migration requires coordination between integrin-mediated cell adhesion to the extracellular matrix and force applied to adhesion sites. Talin plays a key role in coupling integrin receptors to the actomyosin contractile machinery, while deleted in liver cancer 1 (DLC1) is a Rho GAP that binds talin and regulates Rho, and therefore actomyosin contractility. We show that the LD motif of DLC1 forms a helix that binds to the four-helix bundle of the talin R8 domain in a canonical triple-helix arrangement. We demonstrate that the same R8 surface interacts with the paxillin LD1 and LD2 motifs. We identify key charged residues that stabilize the R8 interactions with LD motifs and demonstrate their importance in vitro and in cells. Our results suggest a network of competitive interactions in adhesion complexes that involve LD motifs, and identify mutations that can be used to analyze the biological roles of specific protein-protein interactions in cell migration
Chandra High Energy Grating Observations of the Fe Ka Line Core in Type 2 Seyfert Galaxies: A Comparison with Type 1 Nuclei
We present a study of the core of the Fe Ka emission line at ~6.4 keV in a
sample of type II Seyfert galaxies observed by the Chandra High Energy Grating
(HEG). The sample consists of 29 observations of 10 unique sources. We present
measurements of the Fe Ka line parameters with the highest spectral resolution
currently available. In particular, we derive the most robust intrinsic line
widths for some of the sources in the sample to date. We obtained a weighted
mean FWHM of 2000 \pm 160 km/s for 8 out of 10 sources (the remaining sources
had insufficient signal-to-noise). From a comparison with the optical
emission-line widths obtained from spectropolarimetric observations, we found
that the location of Fe Ka line-emitting material is a factor of ~0.7-11 times
the size of the optical BLR. Furthermore, compared to 13 type I AGNs for which
the best Fe Ka line FWHM constraints were obtained, we found no difference in
the FWHM distribution or the mean FWHM, and this conclusion is independent of
the central black hole mass. This result suggests that the bulk of the Fe Ka
line emission may originate from a universal region at the same radius with
respect to the gravitational radius, ~30,000 Rg on average. By examining the
correlation between the Fe Ka luminosity and the [O IV] line luminosity, we
found a marginal difference in the Fe K line flux between type I and type II
AGNs, but the spread in the ratio of L(Fe) to L([O IV]) is about two orders of
magnitude. Our results confirm the theoretical expectation that the Fe Ka
emission-line luminosity cannot trivially be used as a proxy of the intrinsic
AGN luminosity, unless a detailed comparison of the data with proper models is
applied.Comment: 16 pages, 6 figures, and 2 tables, accepted for publication in Ap
Information loss in local dissipation environments
The sensitivity of entanglement to the thermal and squeezed reservoirs'
parameters is investigated regarding entanglement decay and what is called
sudden-death of entanglement, ESD, for a system of two qubit pairs. The
dynamics of information is investigated by means of the information disturbance
and exchange information. We show that for squeezed reservoir, we can keep both
of the entanglement and information survival for a long time. The sudden death
of information is seen in the case of thermal reservoir
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