1,042 research outputs found
Exclusive tensor meson photoproduction
We study tensor meson photoproduction outside of the resonance region, at
beam energies of few GeVs. We build a model based on Regge theory that includes
the leading vector and axial exchanges. We consider two determinations of the
unknown helicity couplings, and fit to the recent a2 photoproduction data from
CLAS. Both choices give a similar description of the a2 cross section, but
result in different predictions for the parity asymmetries and the f2
photoproduction cross section. We conclude that new measurements of f2
photoproduction in the forward region are needed to pin down the correct
production mechanism. We also extend our predictions to the 8.5 GeV beam
energy, where current experiments are running.Comment: 13 pages, 7 figures, 3 tables. Version accepted for publication on
Phys.Rev.
Low-field Instabilities in NbSn Multifilamentary Wires: the Possible Role of Unreacted Nb
We report an experimental study aiming to demonstrate the not negligible role of unreacted Nb on the magnetic instabilities in superconducting NbSn multifilamentary wires, observable through partial flux jumps at magnetic field values below 0.5 T. The analysed wires were recently developed for use as dipoles required in future high-energy proton accelerators and are based on powder-in-tube technology. We studied both unreacted (only involving Nb filaments) and reacted wires, finding flux jump instabilities in both cases when performing magnetic measurements. The results can be interpreted on the basis of the critical state model and are coherent with the intrinsic stability criterion
ASSESSMENT OF PHYSICAL ACTIVITY IN AN OUTPATIENT OBESITY CLINIC IN SOUTHERN ITALY: RESULTS FROM A STANDARDIZED QUESTIONNAIRE.
PDE-5i Management of Erectile Dysfunction After Rectal Surgery: A Systematic Review Focusing on Treatment Efficacy
Erectile dysfunction (ED) is one of the main functional complications of surgical resections of the rectum due to rectal cancers or inflammatory bowel disease (IBD). The present systematic review aimed at revising ED management strategies applied after rectal resections and their efficacy in terms of improvement of the International Index of Erectile Function (IIEF) score. A literature search was conducted on Medline, EMBASE, Scopus, and Cochrane databases by two independent reviewers following the PRISMA guidelines. Randomized and nonrandomized controlled trials (RCTs, NRCTs), case-control studies, and case series evaluating medical or surgical therapies for ED diagnosed after rectal surgery for both benign and malignant pathologies were eligible for inclusion. Out of 1028 articles initially identified, only five met the inclusion criteria: two RCTs comparing oral phosphodiesterase type-5 inhibitor (PDE-5i) versus placebo; one NRCT comparing PDE-5i versus PDE-5i + vacuum erection devices (VEDs) versus control; and two before-after studies on PDE-5i. A total of 253 (82.7%) rectal cancer patients and 53 (17.3%) IBD patients were included. Based on two RCTs, PDE-5i significantly improved IIEF compared to placebo at 3 months (SMD = 1.07; 95% CI [0.65, 1.48]; p <.00001; I2 = 39%). Improved IIEF was also reported with PDE-5i + VED at 12 months. There is a paucity of articles in the literature that specifically assess efficacy of ED treatments after rectal surgery. Many alternative treatment strategies to PDE-5is remain to be investigated. Future studies should implement standardized preoperative, postoperative, and follow-up sexual function assessment in patients undergoing rectal resections
Mass-dependent cuts in longitudinal phase space
Longitudinal phase space analyses as introduced by van Hove provided a
simplified method of separating different reaction production mechanisms. Cuts
in the longitudinal phase space can help to select specific reaction kinematics
but also induce nonflat acceptance effects in angular distributions. We show
that in photoproduction reactions dominated by t-channel exchanges, selection
of meson or baryon production over a large mass range can be optimized through
calculating mass-dependent cut limits compared to cuts on a van Hove plot
sector alone. A cut is presented that improves this selection of one type of
hadron production by rejecting another. In addition we demonstrate that using
cuts in longitudinal phase space preserves sufficient information to reliably
extract observables from the angular distribution of the final state particles.Comment: 9 pages, 9 figures, copyright AP
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