| 1. |
- Abelev, Betty, et al.
(författare)
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Underlying Event measurements in pp collisions at root s=0.9 and 7 TeV with the ALICE experiment at the LHC
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :7
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Tidskriftsartikel (refereegranskat)abstract
- We present measurements of Underlying Event observables in pp collisions at root s = 0 : 9 and 7 TeV. The analysis is performed as a function of the highest charged-particle transverse momentum p(T),L-T in the event. Different regions are defined with respect to the azimuthal direction of the leading (highest transverse momentum) track: Toward, Transverse and Away. The Toward and Away regions collect the fragmentation products of the hardest partonic interaction. The Transverse region is expected to be most sensitive to the Underlying Event activity. The study is performed with charged particles above three different p(T) thresholds: 0.15, 0.5 and 1.0 GeV/c. In the Transverse region we observe an increase in the multiplicity of a factor 2-3 between the lower and higher collision energies, depending on the track p(T) threshold considered. Data are compared to PYTHIA 6.4, PYTHIA 8.1 and PHOJET. On average, all models considered underestimate the multiplicity and summed p(T) in the Transverse region by about 10-30%.
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| 2. |
- Abelev, Betty, et al.
(författare)
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Long-range angular correlations on the near and away side in p-Pb collisions at root S-NN=5.02 TeV
- 2013
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Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 719:1-3, s. 29-41
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Tidskriftsartikel (refereegranskat)abstract
- Angular correlations between charged trigger and associated particles are measured by the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV for transverse momentum ranges within 0.5 < P-T,P-assoc < P-T,P-trig < 4 GeV/c. The correlations are measured over two units of pseudorapidity and full azimuthal angle in different intervals of event multiplicity, and expressed as associated yield per trigger particle. Two long-range ridge-like structures, one on the near side and one on the away side, are observed when the per-trigger yield obtained in low-multiplicity events is subtracted from the one in high-multiplicity events. The excess on the near-side is qualitatively similar to that recently reported by the CMS Collaboration, while the excess on the away-side is reported for the first time. The two-ridge structure projected onto azimuthal angle is quantified with the second and third Fourier coefficients as well as by near-side and away-side yields and widths. The yields on the near side and on the away side are equal within the uncertainties for all studied event multiplicity and p(T) bins, and the widths show no significant evolution with event multiplicity or p(T). These findings suggest that the near-side ridge is accompanied by an essentially identical away-side ridge. (c) 2013 CERN. Published by Elsevier B.V. All rights reserved.
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| 3. |
- Abelev, Betty, et al.
(författare)
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Measurement of prompt J/psi and beauty hadron production cross sections at mid-rapidity in pp collisions at root s=7 TeV
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :11
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Tidskriftsartikel (refereegranskat)abstract
- The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at root s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L-int = 5.6 nb(-1). The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p(t) > 1,3 GeV/c and rapidity vertical bar y vertical bar < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the psi(2S) and chi(c) resonances, is sigma(prompt J/psi) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 8.3 +/- 0.8(stat.) +/- 1.1 (syst.)(-1.4)(+1.5) (syst. pol.) mu b. The cross section for the production of b-hadrons decaying to J/psi with p(t) > 1.3 GeV/c and vertical bar y vertical bar < 0.9 is a sigma(J/psi <- hB) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 1.46 +/- 0.38 (stat.)(-0.32)(+0.26) (syst.) mu b. The results are compared to QCD model predictions. The shape of the p(t) and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b (b) over bar pair total cross section and d sigma/dy at mid-rapidity.
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| 4. |
- Cruz-Jentoft, Alfonso J, et al.
(författare)
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Prevalence of and interventions for sarcopenia in ageing adults : a systematic review : Report of the International Sarcopenia Initiative (EWGSOP and IWGS)
- 2014
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Ingår i: Age and Ageing. - : Oxford University Press (OUP). - 0002-0729 .- 1468-2834. ; 43:6, s. 748-759
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Forskningsöversikt (refereegranskat)abstract
- OBJECTIVE: to examine the clinical evidence reporting the prevalence of sarcopenia and the effect of nutrition and exercise interventions from studies using the consensus definition of sarcopenia proposed by the European Working Group on Sarcopenia in Older People (EWGSOP).METHODS: PubMed and Dialog databases were searched (January 2000-October 2013) using pre-defined search terms. Prevalence studies and intervention studies investigating muscle mass plus strength or function outcome measures using the EWGSOP definition of sarcopenia, in well-defined populations of adults aged ≥50 years were selected.RESULTS: prevalence of sarcopenia was, with regional and age-related variations, 1-29% in community-dwelling populations, 14-33% in long-term care populations and 10% in the only acute hospital-care population examined. Moderate quality evidence suggests that exercise interventions improve muscle strength and physical performance. The results of nutrition interventions are equivocal due to the low number of studies and heterogeneous study design. Essential amino acid (EAA) supplements, including ∼2.5 g of leucine, and β-hydroxy β-methylbutyric acid (HMB) supplements, show some effects in improving muscle mass and function parameters. Protein supplements have not shown consistent benefits on muscle mass and function.CONCLUSION: prevalence of sarcopenia is substantial in most geriatric settings. Well-designed, standardised studies evaluating exercise or nutrition interventions are needed before treatment guidelines can be developed. Physicians should screen for sarcopenia in both community and geriatric settings, with diagnosis based on muscle mass and function. Supervised resistance exercise is recommended for individuals with sarcopenia. EAA (with leucine) and HMB may improve muscle outcomes.
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| 5. |
- Warlick, Erica, et al.
(författare)
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Reduced intensity conditioning is superior to nonmyeloablative conditioning for older chronic myelogenous leukemia patients undergoing hematopoietic cell transplant during the tyrosine kinase inhibitor era
- 2012
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 119:17, s. 4083-4090
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Tidskriftsartikel (refereegranskat)abstract
- Tyrosine kinase inhibitors (TKIs) and reduced intensity conditioning (RIC)/nonmyeloablative (NMA) conditioning hematopoietic cell transplants (HCTs) have changed the therapeutic strategy for chronic myelogenous leukemia (CML) patients. We analyzed post-HCT outcomes of 306 CML patients reported to the Center for International Blood and Marrow Transplant Research aged 40 years and older undergoing RIC/NMA HCT from 2001 to 2007: 117 (38%) aged 40 to 49 years, 119 (39%) 50 to 59 years, and 70 (23%) 60 years or older. The majority (74%) had treatment with imatinib before HCT. At HCT, most patients aged 40 to 49 years were in chronic phase (CP) 1 (74%), compared with 31% aged 60 years or older. Siblings were donors for 56% aged 40 to 49 years; older cohorts had more unrelated donors. The majority received peripheral blood grafts and RIC across all age groups. 3 year overall survival (54%, 52%, and 41%), day + 100 grade II-IV acute GVHD (26%, 32%, and 32%), chronic GVHD (58%, 51%, and 43%), and 1-year treatment-related mortality (18%, 20%, and 13%) were similar across ages. The 3-year relapse incidence (36%, 43%, and 66%) and disease-free survival (35%, 32%, and 16%) were inferior in the oldest cohort. Importantly, for CP1 patients, relapse and disease-free survival were similar across age cohorts. Allogeneic RIC HCT for older patients with CML can control relapse with acceptable toxicity and survival in TKI-exposed CML, especially if still in CP1.
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| 6. |
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| 7. |
- Chan, Ruth, et al.
(författare)
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Association between serum 25-hydroxyvitamin D and psychological health in older Chinese men in a cohort study.
- 2011
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Ingår i: Journal of affective disorders. - : Elsevier BV. - 1573-2517 .- 0165-0327. ; 130:1-2, s. 251-259
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Few studies evaluated the association between vitamin D and psychological health in Chinese. This study examined these associations in Chinese older men in Hong Kong. METHODS: Baseline serum 25-hydroxyvitamin D (25OHD), depression and cognitive function were assessed in 939 community-dwelling Chinese men aged >65. Data on depression status at 4-year follow up was available in 629 men. Data were collected for confounding factors: demographics, number of diseases, smoking, alcohol use, body mass index, physical activity, mobility limitations, dietary intake, season of blood measurement, and serum parathyroid hormone level. Multivariate logistic regression analyses were performed with adjustments for confounding factors. RESULTS: An inverse association between serum 25OHD and baseline depression was observed. Men in the highest (>=92nmol/L) compared with lowest (<=63nmol/L) quartile of serum 25OHD had an adjusted odds ratio for depression of 0.46 (95% CI: 0.22-0.98, P(trend)=0.004). The association was more pronounced in low vitamin D season than in high vitamin D season. No association was observed between serum 25OHD and incident depression at 4years. Baseline cognitive impairment was not associated with serum 25OHD in all models. LIMITATIONS: Self-reported measure of depression and cognitive performance, the small number of incident depression at 4-year follow up and selection bias may affect the study validity. CONCLUSIONS: Serum 25OHD was inversely associated with depression at baseline and was not linked to baseline cognitive impairment and 4-year incident depression in Chinese older men. Future studies are warranted to evaluate these associations in populations with higher prevalence of vitamin D deficiency.
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| 8. |
- Chan, Ruth, et al.
(författare)
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Not All Elderly People Benefit From Vitamin D Supplementation with Respect to Physical Function: Results From the Osteoporotic Fractures in Men Study, Hong Kong.
- 2012
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Ingår i: Journal of the American Geriatrics Society. - : Wiley. - 1532-5415 .- 0002-8614. ; 60:2, s. 290-295
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To examine vitamin D status and its association with physical performance and muscle mass in older Chinese men. DESIGN: Cross-sectional and prospective cohort study design. SETTING: Hong Kong, People's of Republic of China. PARTICIPANTS: Nine hundred thirty-nine community-dwelling men aged 65 and older for cross-sectional analysis and 714 for longitudinal analysis. MEASUREMENTS: Baseline serum 25-hydroxyvitamin D (25OHD) was measured using a competitive radioimmunoassay kit. Baseline and 4-year physical performance measures (grip strength, 6-m walking speed, step length in a 6-m walk, time to complete five chair stands) were measured, and appendicular skeletal muscle mass (ASM) was assessed using dual-energy X-ray absorptiometry. Data were collected for confounding factors: demographic, number of diseases, smoking, alcohol use, body mass index, physical activity, diet, season of blood sampling, and serum parathyroid hormone (PTH) level. Multivariate regression analyses were performed with adjustments for confounding factors. RESULTS: Mean±standard deviation serum 25OHD level of this sample of Chinese community-dwelling older men who had a high level of baseline physical function was 77.9±20.5nmol/L; 94.1% of participants had serum 25OHD levels of 50nmol/L or greater. Median (interquartile range) serum PTH level was 4.1pmol/L (3.1-5.5pmol/L). After adjustment for potential confounding factors, serum 25OHD levels were not associated with baseline or 4-year change in physical performance measures and ASM. CONCLUSION: In Chinese older men who are vitamin D replete and have a high level of baseline physical function, vitamin D may not have an important role in physical function and muscle mass.
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| 9. |
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| 10. |
- Cho, Jeong-woo, 1978-, et al.
(författare)
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On the Asymptotic Validity of the Decoupling Assumption for Analyzing 802.11 MAC Protocol
- 2012
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Ingår i: IEEE Transactions on Information Theory. - : IEEE Press. - 0018-9448 .- 1557-9654. ; 58:11, s. 6879-6893
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Tidskriftsartikel (refereegranskat)abstract
- Performance evaluation of the 802.11 MAC protocol is classically based on the decoupling assumption, which hypothesizes that the backoff processes at different nodes are independent. This decoupling assumption results from mean field convergence and is generally true in transient regime in the asymptotic sense (when the number of wireless nodes tends to infinity), but, contrary to widespread belief, may not necessarily hold in stationary regime. The issue is often related with the existence and uniqueness of a solution to a fixed point equation; however, it was also recently shown that this condition is not sufficient; in contrast, a sufficient condition is a global stability property of the associated ordinary differential equation. In this paper, we give a simple condition that establishes the asymptotic validity of the decoupling assumption for the homogeneous case (all nodes have the same parameters). We also discuss the heterogeneous and the differentiated service cases and formulate a new ordinary differential equation. We show that the uniqueness of a solution to the associated fixed point equation is not sufficient; we exhibit one case where the fixed point equation has a unique solution but the decoupling assumption is not valid in the asymptotic sense in stationary regime.
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