j_psi Suppression and the Quark-Gluon Plasma

All measured Feynman x_f distributions of the ratio, R, of j_psi production in nuclei relative to production on protons fall off with x_f. They show [2] that absorption of charmonium cannot be the only source of j_psi suppression and that energy loss of the constituents of the incident proton prior to the j_psi production, because of the exponential sqrt(s) dependence of the charmonium cross section, should not be neglected. Including the effects of initial state energy loss we find that the latest measured Pb-Pb j_psi cross sections do not provide any evidence for deconfinement.Comment: 9 pages, 2 figures, additional material, accepted by Physics Letter

Very Long Baseline Neutrino Oscillation Experiment for Precise Measurements of Mixing Parameters and CP Violating Effects

We analyze the prospects of a feasible, Brookhaven National Laboratory based, very long baseline (BVLB) neutrino oscillation experiment consisting of a conventional horn produced low energy wide band beam and a detector of 500 kT fiducial mass with modest requirements on event recognition and resolution. Such an experiment is intended primarily to determine CP violating effects in the neutrino sector for 3-generation mixing. We analyze the sensitivity of such an experiment. We conclude that this experiment will allow determination of the CP phase $\delta_{CP}$ and the currently unknown mixing parameter $\theta_{13}$, if $\sin ^2 2 \theta_{13} \geq 0.01$, a value $\sim 15$ times lower than the present experimental upper limit. In addition to $\theta_{13}$ and $\delta_{CP}$, the experiment has great potential for precise measurements of most other parameters in the neutrino mixing matrix including $\Delta m^2_{32}$, $\sin^2 2\theta_{23}$, $\Delta m^2_{21}\times \sin 2 \theta_{12}$, and the mass ordering of neutrinos through the observation of the matter effect in the $\nu_\mu \to \nu_e$ appearance channel.Comment: 12 pages, 10 figure

Different techniques of surgical left atrial appendage closure and their efficacy. a systematic review

Background: Atrial fibrillation has been identified as an independent risk factor for thromboembolic events. Since 1948 different surgical techniques have described the feasibility and the rationale of left atrial surgical appendage closure. The aim of this systematic review is to evaluate the reported patency rates of different surgical techniques. Methods: This systematic review was conducted according to preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Two independent investigators searched the PubMed, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, and OVID & REG; (Wolters Kluwer, Alphen aan den Rijn, Netherlands) to identify relevant studies. Consecutively, a PICO (Population, Intervention, Comparison and Outcomes) strategy assessment of literature was performed to search eventual other relevant studies that may have been ignored. Results: A total of 42 studies were included in our analysis. The total number of patients who underwent surgical left atrial appendage closure was 5671, and in 61.2% an imaging follow up was performed, mostly with transesophageal echocardiographic evaluation. Success rate for the different techniques was: Clip deployment 98%; Lariat procedure 88%; Surgical amputation 91%; Endocardial suture 74.3%, Epicardial suture 65%; Left atrial appendage closure (LAAC) ligation 60.9%; Stapler technique with excision of left atrial appendage (LAA) 100%; Stapler without excision 70%. Conclusions: To date, data on surgical left atrial appendage closure are poor and not standardized, even if reported rates are acceptable and comparable to transcatheter procedures. If validated on large-scale non-retrospective and multicentric studies, these promising developments may offer a valuable alternative for patients with atrial fibrillation (AF) and ineligible for oral anticoagulation therapy

A Dependence of Hadron Production in Inelastic Muon Scattering and Dimuon Production by Protons

The A dependence of the production of hadrons in inelastic muon scattering and of the production of dimuons in high $Q^2$ proton interactions are simply related. Feynman x distributions and z scaling distributions in nuclei are compared with energy loss models. Suggestions for new data analyses are presented.Comment: 14pp +13 figures, UPR report 607T (available from ftp://dept.physics.upenn.edu/muhad

Atmospheric neutrino flux from 3-dimensional simulation

The atmospheric muon and neutrino flux have been simulated using the same approach which successfully accounted for the recent secondary proton, electron and positron flux measurements in orbit by the AMS experiment. For the muon flux, a good agreement is obtained with the CAPRICE and HEAT data for altitudes ranging from sea level up to about 38 km. The general features of the calculated atmospheric neutrino flux are reported and discussed. The flux obtained at the Super-Kamiokande experiment location are reported and compared with other calculations. For low neutrino energies the flux obtained is significantly smaller than that used in the data analysis of underground experiment. The simulation results for the SOUDAN experiment site are also reported.Comment: 33 pages, 27 figures, 12 tables, final version for Phys. Rev.

Constraints on Three-Neutrino Mixing from Atmospheric and Reactor Data

Observations of atmospheric neutrinos are usually analyzed using the simplifying approximation that either $\nu_\mu \leftrightarrow \nu_\tau$ or $\nu_e \leftrightarrow \nu_\mu$ two-flavor mixing is relevant. Here we instead consider the data using the simplifying approximation that only one neutrino mass scale is relevant. This approximation is the minimal three-flavor notation that includes the two relevant two-flavor approximations. The constraints in the parameter space orthogonal to the usual, two-flavor analyses are studied.Comment: 15 pages, preprint IUHET-26

Cardiac dysfunction in pauci symptomatic human immunodeficiency virus patients: a meta-analysis in the highly active antiretroviral therapy era

Human immunodeficiency virus infection (HIV) has been associated with cardiac dysfunction that, if present, can negatively affect morbidity and mortality of HIV-infected patients. Unfortunately, many of the studies on this topic were performed before the highly active antiretroviral therapy (HAART) was established. Thus, we performed a comprehensive meta-analysis to critically appraise the incidence of cardiac dysfunction in HIV-infected pauci symptomatic patients. Medline, Cochrane Library, and Biomed Central were systematically screened for studies reporting on systolic and/or diastolic dysfunctions in HIV pauci-symptomatic patients. Baseline treatment and cardiac imaging data were appraised and pooled with random effect methods computing summary. At pooled analysis, including a total of 2242 patients from 11 studies, an overall average incidence of traditional cardiovascular risk factors was observed, while a low rate of previous coronary artery disease was reported. Incidence of systolic and diastolic left ventricular dysfunction was 8.33 (95 CI: 2.2014.25) and 43.38 (95 CI: 31.7355.03), respectively. Diastolic dysfunction was graded as first [31.85 (95 CI: 24.8543.73)], second [8.53 (95 CI: 2.1214.93)], and third degree [3.02 (95 CI: 1.784.27)]. At multivariate analysis, a high sensitivity C-reactive protein level 5 mg/L, active tobacco smoking and previous history of myocardial infarction were predictors of left ventricular systolic dysfunction [odd ratio 1.70 (95 CI: 1.032.77); 1.57 (95 CI: 1.032.34); and 15.90 (95 CI: 1.94329.00), respectively]. Hypertension (OR 2.30; 95 CI: 1.204.50) and older age (OR 2.50 per 10 years increase; 95 CI: 1.703.60) were predictors of left ventricular diastolic dysfunction (Figure 3). Systolic and diastolic dysfunction represent a common finding in pauci symptomatic HIV-infected patients, regardless to HAART