1,940 research outputs found

    Bose-Einstein Correlations for Mixed Neutral Mesons

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    Correlations are shown to arise in nonidentical mixed-particle pairs like KoKˉoK^o \bar K^o when observed in identical decay modes like KSKSK_S K_S in multiparticle final states containing many partial waves. No enhancement is found in any single partial wave and all partial wave analyses of the s-wave threshold resonance aoa_o and fof_o should give the same results for all decay modes. In CP violation experiments where BoBˉoB^o - \bar B^o pairs are inclusively produced and correlated decays into ψKS\psi K_S and leptonic modes are observed, the CP-violating lepton asymmetry is enhanced by a factor of two in the kinematic region where Bose enhancement occurs.Comment: 11 page

    Single - particle correlations in events with the total disintegration of nuclei

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    New experimental data on the behaviour of the single-particle two-dimensional correlation functions R versus Q (Q is the number of nucleons emitted from nuc- lei) and Ap (Ap is the mass of projectile nuclei) are presented in this paper. The interactions of protons, d, 4He and 12C nuclei with carbon nuclei (at a momentum of 4.2 A GeV/c) are considered.The values of R are obtained separately for pi minus mesons and protons.In so doing,the values of R are normalized so that -1=<R=<1.The value of R=0 corresponds to the case of the absence of corre- lations.It has been found that the Q- and Ap-dependence of R takes place only for weak correlations (R< 0.3).In the main (90 %),these correlations are con- nected with the variable pt and have a nonlinear character, that is the regi- ons with different characters of the Q-dependence of R are separated: there is a change of regimes in the Q-dependences of R.The correlations weaken with increasing Ap, and the variable R gets the least values of all the considered ones in 12CC interactions.Simultaneously with weakening the correlations in the region of large Q, the character of the Q-dependence of R changes.Comment: 17 pages, submitted to Phys. Rew.

    Relevance of baseline hard proton-proton spectra for high-energy nucleus-nucleus physics

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    We discuss three different cases of hard inclusive spectra in proton-proton collisions: high pTp_T single hadron production at s\sqrt{s}\approx 20 GeV and at s\sqrt{s} = 62.4 GeV, and direct photon production at s\sqrt{s} = 200 GeV; with regard to their relevance for the search of Quark Gluon Plasma signals in A+A collisions at SPS and RHIC energies.Comment: Proceeds. Hot Quarks 2004 Int. Workshop on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions. 26 pages. 26 figs. [minor corrs., refs. added

    Quality of dietary fat and risk of Alzheimer's disease and dementia in adults aged >= 50 years : a systematic review

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    Objective: To identify, critically appraise, and synthesize evidence on the effect of quality of dietary fat intake and different classes of fatty acids on the risk of Alzheimer's disease (AD) and dementia in adults aged >= 50 years. Methods: We searched MEDLINE, EMBASE, Cochrane Central of Controlled Trials, and Scopus for clinical trials and prospective cohort studies published until May 2021. Two reviewers independently screened retrieved literature, extracted relevant data, and performed risk of bias assessment. Classes of fatty acids included were saturated fatty acids (SFAs), trans fatty acids (TFAs), monounsaturated fatty acids (MUFAs), poly-unsaturated fatty acids (PUFAs), and their subtypes and sources. Given between-study heterogeneity, we did not perform meta-analyses but narratively described findings from the studies. Results: From 4,491 identified records, five articles (based on four prospective cohort studies) met the inclusion criteria. Three studies had an overall serious risk of bias, while one study had a moderate risk. Overall, we found no robust association between intake of any fatty acids type and the development of AD and dementia. For example, for SFA and TFA, there was contradictory associations reported on AD: one study found that each unit increase in energy-adjusted intake of SFA (risk ratio (RR) 0.83, 95%CI 0.70 0.98) and TFA (RR 0.80, 95%CI 0.65-0.97) was associated with a decreased risk of AD, but not dementia. For PUFA, one study found that higher quintile intake of marine-based n-3 PUFA was associated with a decreased risk of AD. The intake of other fatty acids was not associated with the outcomes. The certainty of the overall evidence was inconclusive. Conclusion: We found no clear association between the intake of various classes of fatty acids and the risk of AD and dementia in adults. More well-designed prospective studies are required to clarify these findings.Peer reviewe

    Dietary fiber and growth, iron status and bowel function in children 0-5 years old : a systematic review

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    Background: While dietary fiber intake is low in many children, the current trend to plant-based diets is associated with higher fiber intake in children raised on these diets. As older reports indicate that diets providing high fiber intake in children 0-5 years may affect growth, iron status and bowel function, we summarized the available evidence in this systematic review. Objective: To identify, critically appraise, and synthesize evidence on the effect of high fiber intake on growth, iron and bowel function in children 0-5 years, with relevance to the Nordic and Baltic countries. Methods: Following a pre-registered protocol, we searched MEDLINE, EMBASE, Cochrane Central of Controlled Trials, and Scopus for clinical trials and prospective cohort studies published until November 2021. Two reviewers independently screened retrieved literature, extracted relevant data, and performed risk of bias assessment. Outcomes were growth, iron metabolism and bowel function in children 0-5 years. We narratively described findings from studies that met inclusion criteria. Results: From 5,644 identified records, five articles met the inclusion criteria. Two RCTs had an overall moderate risk of bias, while the three observational studies had serious risk. Overall, we found no robust association between high intake of dietary fiber and growth. In the RCTs, higher intake of fiber had a positive effect on bowel movements and constipation. No studies on fiber intake and iron status were identified. The certainty of the overall evidence was inconclusive for growth and bowel function, while no assess-ment was made for iron status. Conclusion: We found no clear association between high intake of dietary fiber and growth or bowel func-tion in young children living in affluent countries, albeit with only a limited number of studies. There is a lack of studies investigating health effects of high fiber intake in small children.Peer reviewe

    Nuts and seeds consumption and risk of cardiovascular disease, type 2 diabetes and their risk factors : a systematic review and meta-analysis

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    Objectives: We aimed to systematically review studies and evaluate the strength of the evidence on nuts/seeds consumption and cardiometabolic diseases and their risk factors among adults. Methods: A protocol was pre-registered in PROSPERO (CRD42021270554). We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials and Scopus up to September 20, 2021 for prospec-tive cohort studies and >= 12-week randomized controlled trials (RCTs). Main outcomes were cardiovascular disease (CVD), coronary heart disease (CHD), stroke and type 2 diabetes (T2D), secondary total-/low density lipoprotein (LDL)-cholesterol, blood pressure and glycaemic markers. Data extraction and risk of bias (RoB) assessments (using RoB 2.0 and RoB-NObS) were performed in duplicate. Effect sizes were pooled using random-effects meta-analyses and expressed as relative risk (RR) or weighted mean differences with 95% confidence intervals (CI); heterogeneity quantified as I2. One-stage dose-response analyses assessed the linear and non-linear associations with CVD, CHD, stroke and T2D. The strength of evidence was classified per the World Cancer Research Fund criteria. Results: After screening 23,244 references, we included 42 papers from cohort studies (28 unique cohorts, 1,890,573 participants) and 18 RCTs (2,266 participants). In the cohorts, mainly populations with low con-sumption, high versus low total nuts/seeds consumption was inversely associated with total CVD (RR 0.81; 95% CI 0.75, 0.86; I-2 = 67%), CVD mortality (0.77; 0.72, 0.82; I-2 = 59.3%), CHD (0.82; 0.76, 0.89; I-2 = 64%), CHD mortality (0.75; 0.65, 0.87; I-2 = 66.9%) and non-fatal CHD (0.85; 0.75, 0.96; I-2 = 62.2%). According to the non-linear dose-response analyses, consumption of 30 g/day of total nuts/seeds was associated with RRs of similar magnitude. For stroke and T2D the summary RR for high versus low intake was 0.91 (95% CI 0.85, 0.97; I-2 = 24.8%) and 0.95 (0.75, 1.21; I-2 = 82.2%). Intake of nuts (median similar to 50 g/day) lowered total (-0.15 mmol/L; -0.22, -0.08; I-2 = 31.2%) and LDL-cholesterol (-0.13 mmol/L; -0.21, -0.05; I-2 = 68.6%), but not blood pressure. Findings on fasting glucose, HbA1c and insulin resistance were conflicting. The results were robust to sensitivity and subgroup analyses. We rated the associations between nuts/seeds and both CVD and CHD as probable. There was limited but suggestive evidence for no association with stroke. No conclusion could be made for T2D. Conclusion: There is a probable relationship between consumption of nuts/seeds and lower risk of CVD, mostly driven by CHD, possibly in part through effects on blood lipids. More research on stroke and T2D may affect the conclusions. The evidence of specific nuts should be further investigated.Peer reviewe

    Light Gluino And Tevatroin Dijet Angular Distributions

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    We consider the effects of a light gluino on the dijet angular distributions in p - pbar collisions at sqrt(s)=1800 GeV. We show that the slower running of alpha_s and the production q qbar, g g -> Gino Gino do not significantly alter the expected angular distributions. On the other hand, single U, D squark production q g -> Q Gino with subsequent Q -> q g results in dijets whose angular distributions are dramatically different from that in SM. The CDF data on dijet angular distributions with integrated luminosity of 106 pb^(-1) exclude U, D squarks in the mass ranges 170 < m < 650 and 190 < m < 600 GeV, We consider lower energies as well and show that in a future experimental analysis for dijet mass below 240 GeV squarks could be observed or ruled out.Comment: 10 pages, LaTeX with 2 epsf figure

    Nonlinear kT factorization for Forward Dijets in DIS off Nuclei in the Saturation Regime

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    We develop the QCD description of the breakup of photons into forward dijets in small-x deep inelastic scattering off nuclei in the saturation regime. Based on the color dipole approach, we derive a multiple scattering expansion for intranuclear distortions of the jet-jet transverse momentum spectrum. A special attention is paid to the non-Abelian aspects of the propagation of color dipoles in a nuclear medium. We report a nonlinear kk_{\perp}-factorization formula for the breakup of photons into dijets in terms of the collective Weizs\"acker-Williams (WW) glue of nuclei as defined in ref. \cite{Saturation,NSSdijet}. For hard dijets with the transverse momenta above the saturation scale the azimuthal decorrelation (acoplanarity) momentum is of the order of the nuclear saturation momentum QA. For minijets with the transverse momentum below the saturation scale the nonlinear kT-factorization predicts a complete disappearance of the jet-jet correlation. We comment on a possible relevance of the nuclear decorrelation of jets to the experimental data from the STAR-RHIC Collaboration.Comment: 40 pages, 7 figure

    Early intervention in Portugal: study of professionals’ perceptions

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    Early intervention (EI) has been characterized by considerable advances in its domain, which has had great repercussions in the implementation of the family-centered approach. These changes have had implications in the practices and in the adoption and learning of new values that should be implemented in EI. This study evaluates the professional perspectives regarding familycentered practices in EI programs in Portugal. The results highlight the importance of effective collaboration and coordination between health, education, and social services and the importance of providing child and family support in a natural context. These results reinforce the need to invest in professional training to improve the quality of services offered to families in EI.Fundação para a Ciência e a Tecnologia (FCT) no âmbito do projecto PEst-OE/CED/UI1661/2014 do CIEd
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