45 research outputs found

    Assessment of post-competition peak blood lactate in male and female master swimmers aged 40–79 years and its relationship with swimming performance

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    The main purpose of this study was to measure the postcompetition blood lactate concentration ([La]b) in master swimmers of both sexes aged between 40 and 79 years in order to relate it to age and swimming performance. One hundred and eight swimmers participating in the World Master Championships were assessed for [La]b and the average rate of lactate accumulation (La’;mmol l-1 s-1) was calculated. In addition, 77 of them were also tested for anthropometric measures. When the subjects were divided into 10-year age groups, males exhibited higher [La]b than women (factorial ANOVA, P < 0.01) and a steeper decline with ageing than female subjects. Overall, mean values (SD) of [La]b were 10.8 (2.8), 10.3 (2.0), 10.3 (1.9), 8.9 (3.2) mmol l-1 in women, and 14.2 (2.5), 12.4 (2.5), 11.0 (1.6), 8.2 (2.0) mmol l-1 in men for, respectively, 40–49, 50–59, 60–69, 70–79 years’ age groups. When, however, [La]b values were normalised for a ‘‘speed index’’, which takes into account swimming speed as a percentage of world record, these sex-related differences, although still present, were considerably attenuated. Furthermore, the differences in La’ between males and females were larger in the 40–49 age group (0.34 vs 0.20 mmol l-1 s-1 for 50-m distance) than in the 70–79 age group (0.12 vs 0.14 mmol l-1 s-1 for 50-m distance). Different physiological factors, supported by the considered anthropometric measurements, are suggested to explain the results

    A development study and randomised feasibility trial of a tailored intervention to improve activity and reduce falls in older adults with mild cognitive impairment and mild dementia

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    Background: People with dementia progressively lose abilities and are prone to falling. Exercise- and activity-based interventions hold the prospect of increasing abilities, reducing falls, and slowing decline in cognition. Current falls prevention approaches are poorly suited to people with dementia, however, and are of uncertain effectiveness. We used multiple sources, and a co-production approach, to develop a new intervention, which we will evaluate in a feasibility randomised controlled trial (RCT), with embedded adherence, process and economic analyses. Methods: We will recruit people with mild cognitive impairment or mild dementia from memory assessment clinics, and a family member or carer. We will randomise participants between a therapy programme with high intensity supervision over 12 months, a therapy programme with moderate intensity supervision over 3 months, and brief falls assessment and advice as a control intervention. The therapy programmes will be delivered at home by mental health specialist therapists and therapy assistants. We will measure activities of daily living, falls and a battery of intermediate and distal health status outcomes, including activity, balance, cognition, mood and quality of life. The main aim is to test recruitment and retention, intervention delivery, data collection and other trial processes in advance of a planned definitive RCT. We will also study motivation and adherence, and conduct a process evaluation to help understand why results occurred using mixed methods, including a qualitative interview study and scales measuring psychological, motivation and communication variables. We will undertake an economic study, including modelling of future impact and cost to end-of-life, and a social return on investment analysis. Discussion: In this study, we aim to better understand the practicalities of both intervention and research delivery, and to generate substantial new knowledge on motivation, adherence and the approach to economic analysis. This will enable us to refine a novel intervention to promote activity and safety after a diagnosis of dementia, which will be evaluated in a definitive randomised controlled trial.\ud Trial registration: ClinicalTrials.gov: NCT02874300; ISRCTN 10550694

    QCD and strongly coupled gauge theories : challenges and perspectives

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    We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe

    Is exposure to formaldehyde in air causally associated with leukemia?—A hypothesis-based weight-of-evidence analysis

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    Recent scientific debate has focused on the potential for inhaled formaldehyde to cause lymphohematopoietic cancers, particularly leukemias, in humans. The concern stems from certain epidemiology studies reporting an association, although particulars of endpoints and dosimetry are inconsistent across studies and several other studies show no such effects. Animal studies generally report neither hematotoxicity nor leukemia associated with formaldehyde inhalation, and hematotoxicity studies in humans are inconsistent. Formaldehyde's reactivity has been thought to preclude systemic exposure following inhalation, and its apparent inability to reach and affect the target tissues attacked by known leukemogens has, heretofore, led to skepticism regarding its potential to cause human lymphohematopoietic cancers. Recently, however, potential modes of action for formaldehyde leukemogenesis have been hypothesized, and it has been suggested that formaldehyde be identified as a known human leukemogen. In this article, we apply our hypothesis-based weight-of-evidence (HBWoE) approach to evaluate the large body of evidence regarding formaldehyde and leukemogenesis, attending to how human, animal, and mode-of-action results inform one another. We trace the logic of inference within and across all studies, and articulate how one could account for the suite of available observations under the various proposed hypotheses. Upon comparison of alternative proposals regarding what causal processes may have led to the array of observations as we see them, we conclude that the case fora causal association is weak and strains biological plausibility. Instead, apparent association between formaldehyde inhalation and leukemia in some human studies is better interpreted as due to chance or confounding
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