3,895 research outputs found
Essential role for proteinase-activated receptor-2 in arthritis
Using physiological, pharmacological, and gene disruption approaches, we demonstrate that proteinase-activated receptor-2 (PAR-2) plays a pivotal role in mediating chronic inflammation. Using an adjuvant monoarthritis model of chronic inflammation, joint swelling was substantially inhibited in PAR-2-deficient mice, being reduced by more than fourfold compared with wild-type mice, with virtually no histological evidence of joint damage. Mice heterozygous for PAR-2 gene disruption showed an intermediate phenotype. PAR-2 expression, normally limited to endothelial cells in small arterioles, was substantially upregulated 2 weeks after induction of inflammation, both in synovium and in other periarticular tissues. PAR-2 agonists showed potent proinflammatory effects as intra-articular injection of ASKH95, a novel synthetic PAR-2 agonist, induced prolonged joint swelling and synovial hyperemia. Given the absence of the chronic inflammatory response in the PAR-2-deficient mice, our findings demonstrate a key role for PAR-2 in mediating chronic inflammation, thereby identifying a novel and important therapeutic target for the management of chronic inflammatory diseases such as rheumatoid arthritis
Study of the Gauge Mediation Signal with Non-pointing Photons at the CERN LHC
In this paper we study the gauge mediation signal with the ATLAS detector at
the CERN LHC. We focus on the case where the NLSP is the long-lived lightest
neutralino () which decays dominantly into a photon
() and a gravitino (). A non-pointing photon from the
neutralino decay can be detected with good position and time resolutions by the
electormagnetic calorimeter (ECAL), while the photon momentum would be
precisely measured if the photon is converted inside the inner tracking
detector before reaching the ECAL. A new technique is developed to determine
the masses of the slepton () and the neutralino from events with
a lepton and a converted non-pointing photon arising from the cascade decay
. A Monte Carlo
simulation at a sample point shows that the masses would be measured with an
error of 3% for (100) selected pairs. Once the sparticle
masses are determined by this method, the decay time and momentum of the
neutralino are solved using the ECAL data and the lepton momentum only, for all
pairs without the photon conversion. We estimate the sensitivity
to the neutralino lifetime for cm to (10) m.Comment: 19 page, 7 figures, revte
Towards a Pervasive Access Control within Video Surveillance Systems
Part 1: Cross-Domain Conference and Workshop on Multidisciplinary Research and Practice for Information Systems (CD-ARES 2013)International audienceThis paper addresses two emerging challenges that multimedia distributed systems have to deal with: the user’s constant mobility and the information’s sensitivity. The systems have to adapt, in real time, to the user’s context and situation in order to provide him with relevant results without breaking the security and privacy policies. Distributed multimedia systems, such as the oneproposed by the LINDO project, do not generally consider both issues. In this paper, we apply an access control layer on top of the LINDO architecture that takes into consideration the user’s context and situation and recommends alternative resources to the user when he is facing an important situation. The proposed solution was implemented and tested in a video surveillance use case
Squark and Gluino Production with Jets
We present cross section predictions for squark and gluino production at the
LHC, in association with up to two additional hard jets. These cross sections
can be very large in comparison to the inclusive Born rates. Because hadron
collider experiments utilize hard jets in the reconstruction of cascade decays
or as a way to separate squark and gluino production, the understanding of
these processes is crucial. We show to what degree hard jet radiation can be
described by shower algorithms and point out how tuning these showers, for
example to top quark pair production, could help reduce theoretical
uncertainties for new physics searches at the LHC.Comment: 5 p, 2 fig, 1 tab; version to appear in PLB; added comments on
uncertainty estimate
Supersymmetric particle mass measurement with the boost-corrected contransverse mass
A modification to the contransverse mass (MCT) technique for measuring the
masses of pair-produced semi-invisibly decaying heavy particles is proposed in
which MCT is corrected for non-zero boosts of the centre-of-momentum (CoM)
frame of the heavy states in the laboratory transverse plane. Lack of knowledge
of the mass of the CoM frame prevents exact correction for this boost, however
it is shown that a conservative correction can nevertheless be derived which
always generates an MCT value which is less than or equal to the true value of
MCT in the CoM frame. The new technique is demonstrated with case studies of
mass measurement with fully leptonic ttbar events and with SUSY events
possessing a similar final state.Comment: 33 pages, 33 .eps figures, JHEP3 styl
Prospects of Searches for Gauge Mediated Supersymmetry with h^0 -> {\chi}_1^0 {\chi}_1^0 production in the Time-Delayed Photon + MET Final State at the Tevatron
We propose a search for direct production and decay of the lightest
supersymmetric Higgs boson to two neutralinos in gauge mediated models at the
Fermilab Tevatron. We focus on the final state where each neutralino decays to
photon and light gravitino with a lifetime of order O(ns). In the detector this
will show up as a photon with a time-delayed signature and missing E_T. We
estimate that using the photon timing system at CDF, and the full 10/fb data
sample, that the sensitivity can be within a factor of three in some regions of
parameter space for direct production of the Higgs.Comment: 15 pages, 5 figures, 1 tabl
Physics at the e+ e- Linear Collider
A comprehensive review of physics at an e+e- Linear Collider in the energy
range of sqrt{s}=92 GeV--3 TeV is presented in view of recent and expected LHC
results, experiments from low energy as well as astroparticle physics.The
report focuses in particular on Higgs boson, Top quark and electroweak
precision physics, but also discusses several models of beyond the Standard
Model physics such as Supersymmetry, little Higgs models and extra gauge
bosons. The connection to cosmology has been analyzed as well.Comment: 179 pages, plots and references updated, version to be published at
EPJ
Les Houches "Physics at TeV Colliders 2003" Beyond the Standard Model Working Group: Summary Report
The work contained herein constitutes a report of the ``Beyond the Standard
Model'' working group for the Workshop "Physics at TeV Colliders", Les Houches,
France, 26 May--6 June, 2003. The research presented is original, and was
performed specifically for the workshop. Tools for calculations in the minimal
supersymmetric standard model are presented, including a comparison of the dark
matter relic density predicted by public codes. Reconstruction of
supersymmetric particle masses at the LHC and a future linear collider facility
is examined. Less orthodox supersymmetric signals such as non-pointing photons
and R-parity violating signals are studied. Features of extra dimensional
models are examined next, including measurement strategies for radions and
Higgs', as well as the virtual effects of Kaluza Klein modes of gluons. An LHC
search strategy for a heavy top found in many little Higgs model is presented
and finally, there is an update on LHC studies.Comment: 113 pages, ed B.C. Allanach, v5 has changes to part XV
Hadronic production of bottom-squark pairs with electroweak contributions
We present the complete computation of the tree-level and the next-to-leading
order electroweak contributions to bottom-squark pair production at the LHC.
The computation is performed within the minimal supersymmetric extension of the
Standard Model. We discuss the numerical impact of these contributions in
several supersymmetric scenarios.Comment: 33 pages, v2: preprint numbers correcte
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