450 research outputs found

    Vortex Multiplication in Applied Flow: the Precursor to Superfluid Turbulence

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    The dynamics of quantized vortices in rotating 3^3He-B is investigated in the low density (single-vortex) regime as a function of temperature. An abrupt transition is observed at 0.5Tc0.5 T_{\rm c}. Above this temperature the number of vortex lines remains constant, as they evolve to their equilibrium positions. Below this temperature the number of vortices increases linearly in time until the vortex density has grown sufficiently for turbulence to switch on. On the basis of numerical calculations we suggest a mechanism responsible for vortex formation at low temperatures and identify the mutual friction parameter which governs its abrupt temperature dependence.Comment: 5 pages, 4 figures; version submitted to Phys. Rev. Let

    Home care needs of extremely obese elderly european women

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    Objective: To examine the health and needs of extremely obese women aged over 65 years receiving home care in Europe. Study design: A cross-sectional assessment study based on the Aged in Home Care (AdHOC) project recruited 2974 women aged 65 or over who were receiving home care at 11 sites in European countries. Extreme obesity was defined as ‘Obesity of such a degree as to interfere with normal activities, including respiration’. Main outcome measures: Resident Assessment Instrument for Home Care (RAI-HC version 2.0); Activity of Daily Living Scale; Instrumental Activity of Daily Living Scale; the Minimum Data Set Cognitive Performance Scale; and a health profile. Results: One hundred and twenty women (4.0%) were extremely obese. They were younger than their thinner counterparts, with a median age of 78.3 versus 83.3 years, and they more often had multiple health complaints and needed more help with mobility outside the home. The extremely obese had received home care longer than the non-extremely obese (median 28.7 versus 36.6 months). Extremely obese women also needed more help with personal care than the other group and, due to lower age, they were less cognitively impaired. Conclusions: Extreme obesity is a problem that increasingly affects home care of elderly women

    Effect of Protein Supplementation on Physical Performance in Older People With Sarcopenia-A Randomized Controlled Trial

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    Objectives: To test the long-term effects of whey-enriched protein supplementation on muscle and physical performance. Design: A 12-month randomized controlled double blind trial with a 43-month of post-trial follow-up. Setting: Porvoo, Finland. Participants: A total of 218 older (>74 years of age) community-dwelling people with sarcopenia. Intervention: (1) Control with no supplementation; (2) isocaloric placebo; and (3) 20 g x 2 whey-enriched protein supplementation. All participants were given instructions on home-based exercise, dietary protein, and vitamin D supplementation of 20 mu g/d. Measurements: Physical performance was assessed by short physical performance battery and continuous summary physical performance scores. Hand grip strength and calf intracellular resistance based skeletal muscle index were measured by bioimpedance spectroscopy. The measurements were performed at 0, 6, and 12 months. The post-trial follow-up was performed by a postal questionnaire and national census record data. Results: The participants were older (75-96 years of age) and mostly women (68%). The test supplements had no significant effects on physical performance; the 12-month changes for short physical performance battery were -0.55, -.05, and 0.03 points in control, isocaloric, and protein groups (P = .17), respectively. The changes in continuous summary physical performance scores were similar between the intervention groups (P = .76). The hand grip strength decreased significantly in all intervention groups, and the 12-month changes in calf intracellular resistance-based skeletal muscle index were minor and there were no differences between the intervention groups. One-half of the patients (56%) in both supplement groups reported mild gastrointestinal adverse effects. Differences were found neither in the all-cause mortality nor physical functioning in the post-trial follow-up. Conclusions: The whey-enriched protein supplementation in combination with low intensity home-based physical exercise did not attenuate the deterioration of muscle and physical performance in community-dwelling older people with sarcopenia. (C) 2019 AMDA - The Society for Post-Acute and Long-Term Care Medicine.Peer reviewe

    Flow Phase Diagram for the Helium Superfluids

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    The flow phase diagram for He II and 3^3He-B is established and discussed based on available experimental data and the theory of Volovik [JETP Letters {\bf{78}} (2003) 553]. The effective temperature - dependent but scale - independent Reynolds number Reeff=1/q=(1+α)/αRe_{eff}=1/q=(1+\alpha')/\alpha, where α\alpha and α\alpha' are the mutual friction parameters and the superfluid Reynolds number characterizing the circulation of the superfluid component in units of the circulation quantum are used as the dynamic parameters. In particular, the flow diagram allows identification of experimentally observed turbulent states I and II in counterflowing He II with the turbulent regimes suggested by Volovik.Comment: 2 figure

    Insulin-like growth factor-I and prostate cancer: a meta-analysis

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    Some, but not all, epidemiological found have shown that high circulating levels of insulin-like growth factor-I (IGF-I) are associated with an increased risk of prostate cancer. We performed a meta-analysis on all the studies reported so far to evaluate this association. In our Medline search, 14 case–control studies were identified. A standard protocol abstracted information for each study. Hedges' standardized mean difference (HSMD) and odds ratio (OR) were used to estimate the effect of IGF-I and IGF-binding proteins (IGFBP-3). The combined data showed that circulating levels of IGF-I were significantly higher in prostate cancer patients (HSMD = 0.194). The OR for prostate cancer was 1.47 (95% confidence interval (CI) 1.23–1.77) among men with high IGF-I compared to those with low IGF-I. The OR was 1.26 (95% CI 1.03–1.54) for IGFBP-3. Circulating levels of IGF-I and IGFBP-3 are likely to be higher in prostate cancer patients than in the controls. These findings support the suggestion that high IGF-I and IGFBP-3 are associated with an increased risk of prostate cancer. © 2001 Cancer Research Campaignhttp://www.bjcancer.co

    Effect of comorbidities on survival in patients > 80 years of age at onset of renal replacement therapy: data from the ERA-EDTA Registry

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    Background. The number of elderly patients on renal replacement therapy (RRT) is increasing. The survival and quality of life of these patients may be lower if they have multiple comorbidities at the onset of RRT. The aim of this study was to explore whether the effect of comorbidities on survival is similar in elderly RRT patients compared with younger ones. Methods. Included were 9333 patients >= 80years of age and 48352 patients 20-79 years of age starting RRT between 2010 and 2015 from 15 national or regional registries submitting data to the European Renal Association-European Dialysis and Transplantation Association Registry. Patients were followed until death or the end of 2016. Survival was assessed by Kaplan-Meier curves and the relative risk of death associated with comorbidities was assessed by Cox regression analysis. Results. Patients >= 80years of age had a greater comorbidity burden than younger patients. However, relative risks of death associated with all studied comorbidities (diabetes, ischaemic heart disease, chronic heart failure, cerebrovascular disease, peripheral vascular disease and malignancy) were significantly lower in elderly patients compared with younger patients. Also, the increase in absolute mortality rates associated with an increasing number of comorbidities was smaller in elderly patients. Conclusions. Comorbidities are common in elderly patients who enter RRT, but the risk of death associated with comorbidities is less than in younger patients. This should be taken into account when assessing the prognosis of elderly RRT patients.Peer reviewe

    The sensitivity of the vortex filament method to different reconnection models

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    We present a detailed analysis on the effect of using different algorithms to model the reconnection of vortices in quantum turbulence, using the thin-filament approach. We examine differences between four main algorithms for the case of turbulence driven by a counterflow. In calculating the velocity field we use both the local induction approximation (LIA) and the full Biot-Savart integral. We show that results of Biot-Savart simulations are not sensitive to the particular reconnection method used, but LIA results are.Comment: 9 pages, 9 figure
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