3,656 research outputs found
Higgs Boson Discovery and Properties
We outline issues examined and progress made by the Light Higgs Snowmass 1996
working group regarding discovering Higgs bosons and measuring their detailed
properties. We focused primarily on what could be learned at LEP2, the Tevatron
(after upgrade), the LHC, a next linear \epem collider and a \mupmum
collider.Comment: 47 pages, full postscript file also available via anonymous ftp at
ftp://ucdhep.ucdavis.edu/gunion/summary_snowmass96.ps To appear in
``Proceedings of the 1996 DPF/DPB Summer Study on New Directions for High
Energy Physics''. Minor revisions of references and wording have been made in
a few place
Assessment of Identity Disturbance: Factor Structure and Validation of the Personality Structure Questionnaire in an Italian Sample
here are few brief measures of identity disturbance for use in clinical
practice
that have
been subject to any cross
-
culturally validation
. This study investigated the construct
validity of the Personality Structure Questionnaire (PSQ)
in Italian
clinical (N=237) and
community (
N=296) samples
. Confirmatory factor analysis was conducted to
investigate the internal structure of the PSQ. A three
–
factor structure (i.e., differing self
-
states, mood variability and behavioral loss of control) including
a second
-
order factor
provided the best fit to the data
. This structure was
demonstrated to be invariant across
sex
and
clinical
diagnosis
, with clinical diagnosis significantly predicting increased
PSQ
scores
.
A g
lobal
PSQ score
of
between 26
-
28 was found to be an appropriate cut-off for
assisting in diagnostic processes. Implications for the assessment and treatment of
psychological disorders with a marked identity disturbance component are discussed
A large deviation theory perspective on nanoscale transport phenomena
Understanding transport processes in complex nanoscale systems, like ionic
conductivities in nanofluidic devices or heat conduction in low dimensional
solids, poses the problem of examining fluctuations of currents within
nonequilibrium steady states and relating those fluctuations to nonlinear or
anomalous responses. We have developed a systematic framework for computing
distributions of time integrated currents in molecular models and relating
cumulants of those distributions to nonlinear transport coefficients. The
approach elaborated upon in this perspective follows from the theory of
dynamical large deviations, benefits from substantial previous formal
development, and has been illustrated in several applications. The framework
provides a microscopic basis for going beyond traditional hydrodynamics in
instances where local equilibrium assumptions break down, which are ubiquitous
at the nanoscale.Comment: Small revisions for clarit
Renal Stone Formation in Patients with Inflammatory Bowel Disease
Kidney stones are more common in patients with inflammatory bowel disease (IBD) than in the general population. The main lithogenetic risk factors were evaluated in patients affected by Crohn\u27s disease and ulcerative colitis. Our results show the presence of several factors, besides hyperoxaluria, in patients with IBD although their behaviour appears different in Crohn\u27s disease and ulcerative colitis at pre- and post-operative stages. Before surgery in patients with Crohn\u27s disease we found a decreased citrate (p \u3c 0.001) and magnesium (p \u3c 0.005) excretion together with a low urinary volume (p \u3c 0.001) and pH (p \u3c 0.005). After surgery patients with Crohn\u27s disease showed a further reduction of magnesium and citrate. Patients with ulcerative colitis before surgery showed a reduced citrate excretion (p \u3c 0.05) and a more acidic pH (p \u3c 0.05) than healthy subjects. Surgical treatment of proctocolectomy with ileal pouch-anal anastomosis seems to increase the risk of stone formation; in fact, after surgery we observed a relevant decrease of urinary volume (p \u3c 0.001), pH (p \u3c 0.0001) and urinary excretion of citrate (p \u3c0.0001) as well as magnesium (p \u3c 0.005). Patients with IBD seem to be at greater risk of stone formation than patients with idiopathic calcium lithiasis; in fact, they show a lower excretion of citrate (p \u3c 0.001) and magnesium (p \u3c 0.001) together with a low urinary pH (p \u3c 0.001) and volume (p \u3c 0.001). Urinary volume reduction is probably one of the major risk factors together with the decrease of small molecular weight inhibitors that is a constant finding in all patients with IBD
Combined carriership of TLR9-1237C and CD14-260T alleles enhances the risk of developing chronic relapsing pouchitis
AIM: To investigate the single nucleotide polymorphisms (SNPs) in genes involved in bacterial recognition and the susceptibility to pouchitis or pouchitis severity. METHODS: Analyses of CD14 -260C>T, CARD15/NOD2 3020insC, Toll-like receptor (TLR)4 +896A>G, TLR9 -1237T>C, TLR9+2848G>A, and IRAKM + 22148G>A SNPs were performed in 157 ileal-pouch anal anastomosis (IPAA) patients (79 patients who did not develop pouchitis, 43 infrequent pouchitis patients, 35 chronic relapsing pouchitis patients) and 224 Italian Caucasian healthy controls. RESULTS: No significant differences were found in SNP frequencies between controls and IPAA patients. However, a significant difference in carriership frequency of the TLR9-1237C allele was found between the infrequent pouchitis and chronic relapsing pouchitis groups [P = 0.028, oddos ratio (OR) = 3.2, 95%CI = 1.2-8.6]. This allele uniquely represented a 4-locus TLR9 haplotype comprising both studied TLR9 SNPs in Caucasians. Carrier trait analysis revealed an enhanced combined carriership of the alleles TLR9 -1237C and CD14 -260T in the chronic relapsing pouchitis and infrequent pouchitis group (P = 0.018, OR = 4.1, 95%CI = 1.4 -12.3). CONCLUSION: There is no evidence that the SNPs predispose to the need for IPAA surgery. The significant increase of the combined carriership of the CD14 -260T and TLR9 -1237C alleles in the chronic relapsing pouchitis group suggests that these markers identify a subgroup of IPAA patients with a risk of developing chronic or refractory pouchitis
Weakly-Coupled Higgs Bosons and Precision Electroweak Physics
We examine the prospects for discovering and elucidating the weakly-coupled Higgs sector at future collider experiments. The Higgs search consists of three phases: (i) discovery of a Higgs candidate, (ii) verification of the Higgs interpretation of the signal, and (iii) precision measurements of Higgs sector properties. The discovery of one Higgs boson with Standard Model properties is not sufficient to expose the underlying structure of the electroweak symmetry breaking dynamics. It is critical to search for evidence for a non-minimal Higgs sector and/or new physics associated with electroweak symmetry breaking dynamics. An improvement in precision electroweak data at future colliders can play a useful role in confirming the theoretical interpretation of the Higgs search results
Energy Linearity and Resolution of the ATLAS Electromagnetic Barrel Calorimeter in an Electron Test-Beam
A module of the ATLAS electromagnetic barrel liquid argon calorimeter was
exposed to the CERN electron test-beam at the H8 beam line upgraded for
precision momentum measurement. The available energies of the electron beam
ranged from 10 to 245 GeV. The electron beam impinged at one point
corresponding to a pseudo-rapidity of eta=0.687 and an azimuthal angle of
phi=0.28 in the ATLAS coordinate system. A detailed study of several effects
biasing the electron energy measurement allowed an energy reconstruction
procedure to be developed that ensures a good linearity and a good resolution.
Use is made of detailed Monte Carlo simulations based on Geant which describe
the longitudinal and transverse shower profiles as well as the energy
distributions. For electron energies between 15 GeV and 180 GeV the deviation
of the measured incident electron energy over the beam energy is within 0.1%.
The systematic uncertainty of the measurement is about 0.1% at low energies and
negligible at high energies. The energy resolution is found to be about 10%
sqrt(E) for the sampling term and about 0.2% for the local constant term
- …