Electron-Ion Collider: The next QCD frontier Accardi, A; Albacete, J L; Anselmino, M ...
European physical journal. A, Hadrons and nuclei,
09/2016, Letnik:
52, Številka:
9
Journal Article
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This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader ...nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics over the past decades and, in particular, the focused ten-week program on “Gluons and quark sea at high energies” at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them. It has been benefited profoundly from inputs by the users’ communities of BNL and JLab. This White Paper offers the promise to propel the QCD science program in the US, established with the CEBAF accelerator at JLab and the RHIC collider at BNL, to the next QCD frontier.
The quantitative knowledge of heavy nuclei’s partonic structure is currently limited to rather large values of momentum fraction x-robust experimental constraints below x∼10−2 at low resolution scale ...Q2 are particularly scarce. This is in sharp contrast to the free proton’s structure which has been probed in Deep Inelastic Scattering (DIS) measurements down to x∼10−5 at perturbative resolution scales. The construction of an electron-ion collider (EIC) with a possibility to operate with a wide variety of nuclei, will allow one to explore the low-x region in much greater detail. In the present paper we simulate the extraction of the nuclear structure functions from measurements of inclusive and charm reduced cross sections at an EIC. The potential constraints are studied by analyzing simulated data directly in a next-to-leading order global fit of nuclear Parton Distribution Functions based on the recent EPPS16 analysis. A special emphasis is placed on studying the impact an EIC would have on extracting the nuclear gluon parton distribution function, the partonic component most prone to nonlinear effects at low Q2. In comparison to the current knowledge, we find that the gluon parton distribution function can be measured at an EIC with significantly reduced uncertainties.
We present the EpIC Monte Carlo event generator for exclusive processes based on generalised parton distributions. EpIC utilises the PARTONS framework, which provides a flexible software architecture ...and a variety of modelling options for the partonic description of the nucleon. The generator offers a comprehensive set of features, including simulation of a variety of exclusive processes and radiative corrections. It may be used both in the analysis of experimental data, as well as for impact studies, especially for the future electron-ion colliders.
This literature review focuses on the neonatal context. It provides an update of knowledge on the psychosocial consequences and communication needs expressed by parents. It highlights the obstacles ...to communication and proposes lines of thought for the development of new training systems to improve the communication practices of caregivers.
This review aims to assess and categorize the specific needs and expectations of families in terms of communication within the neonatal intensive care unit (NICU).
A bibliographic search was carried out on the Web of Sciences, PubMed and PsycArticles databases with the following keywords: “neonat* AND new* AND communication AND parent*”.
In total, 16 papers were selected showing that information and communication are particular needs for parents in NICUs. They are confronted with a stressful situation and have to deal with the fear and anticipation of the situation in a context of uncertainty. Parents are satisfied with the caregiver–parent relationship when the type of communication is adapted to the context and to their changing needs. Conversely, they feel excluded when they cannot be involved as they would like to be in the care or in the decision-making process.
The development of new communication training methods and tools such as simulation would allow healthcare workers to acquire new communication skills focused on the needs of families.
Abstract Background and aims Diet may play an important role in the development of hyperuricemia and gout. However, the association between dietary factors and hyperuricemia remains unclear, and few ...studies have investigated direct links between food intake and hyperuricemia. The aim of this study was to investigate associations between high purine-content foods and protein intake with the prevalence of hyperuricemia by using data from a cross-sectional study of 3978 men aged 40–74 yrs living in Shanghai, China. Methods and Results Hyperuricemia was defined as blood uric acid level >7.0 mg/dl. One quarter of this population had hyperuricemia. Dietary information was collected by using a food frequency questionnaire. We collected information on anthropometric measurements and lifestyle factors and other potential confounding factors and disease history via interviews. Total protein consumption was not associated with hyperuricemia. We found a positive association between protein from animal sources and prevalence of hyperuricemia and an inverse association between protein from plant sources and hyperuricemia. However, these associations failed to reach significance in mutually adjusted analysis. Seafood intake was associated with higher prevalence of hyperuricemia. The ORs for quintiles of seafood intake (including fish and shellfish) were 1.00, 1.49, 1.35, 1.34, and 1.56 (p for trend: 0.01). An inverse association approaching significance between soy food consumption and hyperuricemia was observed (ORs: 1.00, 0.90, 0.70, 0.89, and 0.77 for quintiles of intake; p for trend: 0.07). No associations between consumption of purine-rich vegetables or meat and prevalence of hyperuricemia were observed. Conclusions Our data suggest a direct association between seafood consumption and hyperuricemia and an inverse association between consumption of soy food and hyperuricemia among middle-aged, Chinese men.
Abstract Background and aims Some nutraceuticals are prescribed as lipid-lowering substances. However, doubts remain about their efficacy. We evaluated the effects of a nutraceutical combination ...(NC), consisting of 500 mg berberine, 200 mg red yeast rice and 10 mg policosanols, on cholesterol levels and endothelial function in patients with hypercholesterolemia. Methods and results In this single centre, randomized, double-blind, placebo-controlled study, 50 hypercholesterolemic patients (26 males and 24 females, mean age 55 ± 7 years, total cholesterol 6.55 ± 0.75 mmol/l, BMI 28 ± 3.5) were randomized to 6 weeks of treatment with a daily oral dose of NC (25 patients) or placebo (25 patients). In a subsequent open-label extension of 4 weeks, the whole sample received NC. The main outcome measure was decrease total cholesterol (C) levels in the NC arm. Secondary outcome measures were decreased low-density lipoprotein cholesterol (LDL-C) and triglyceride levels, and improved endothelial-dependent flow-mediated dilation (FMD) and insulin sensitivity in relation to NC. Evaluation of absolute changes from baseline showed significant reductions in NC versus placebo for C and LDL-C (C: −1.14 ± 0.88 and −0.03 ± 0.78 mmol/l, p < 0.001; LDL-C: −1.06 ± 0.75 and −00.4 ± 0.54 mmol/l, p < 0.001), and a significant improvement of FMD (3 ± 4% and 0 ± 3% respectively, p < 0.05). After the extension phase, triglyceride levels decreased significantly from 1.57 ± 0.77 to 1.26 ± 0.63 mmol/l, p < 0.05 and insulin sensitivity improved in a patient subgroup with insulin resistance at baseline (HOMA: from 3.3 ± 0.4 to 2.5 ± 1.3, p < 0.05). No adverse effect was reported. Conclusions This NC reduces cholesterol levels. The reduction is associated with improved endothelial function and insulin sensitivity.
A
bstract
Several observables for the deeply virtual Compton scattering process have been simulated in the kinematic regime of a proposed Electron-Ion Collider to explore the possible impact of such ...measurements for the phenomenological access of generalized parton distributions. In particular, emphasis is given to the transverse distribution of sea quarks and gluons and how such measurements can provide information on the angular momentum sum rule. The exact lepton energy loss dependence for the unpolarized
t
-differential electroproduction cross section, needed for a Rosenbluth separation, is also reported.
The oxidation hypothesis of atherogenesis has been the focus of much research over the past 2 decades. However, randomized placebo-controlled trials evaluating the efficacy of vitamin E in preventing ...cardiovascular events in aggregate have failed to show a beneficial effect. Implicit in these trials is that the dose of vitamin E tested effectively suppressed oxidative stress status but this was never determined. We defined the dose-dependent effects of vitamin E (
RRR-α-tocopherol) to suppress plasma concentrations of F
2-isoprostanes, a biomarker of free radical-mediated lipid peroxidation, in participants with polygenic hypercholesterolemia and enhanced oxidative stress, a population at risk for cardiovascular events. A time-course study was first performed in participants supplemented with 3200 IU/day of vitamin E for 20 weeks. A dose-ranging study was then performed in participants supplemented with 0, 100, 200, 400, 800, 1600, or 3200 IU/day of vitamin E for 16 weeks. In the time-course study, maximum suppression of plasma F
2-isoprostane concentrations did not occur until 16 weeks of supplementation. In the dose-ranging study there was a linear trend between the dosage of vitamin E and percentage reduction in plasma F
2-isoprostane concentrations which reached significance at doses of 1600 IU (35
±
2%,
p
<
0.035) and 3200 IU (49
±
10%,
p
<
0.005). This study provides information on the dosage of vitamin E that decreases systemic oxidant stress in vivo in humans and informs the planning and evaluation of clinical studies that assess the efficacy of vitamin E to mitigate disease.
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