303 research outputs found

    Effects of Acetate on Cation Exchange Capacity of a Zn-Containing Montmorillonite:Physicochemical Significance and Metal Uptake

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    Fundamental properties such as cation exchange capacity (CEC), permanent charge, pH(PZC), and metal uptake of a Zn-containing montmorillonite are modified, in a predictable manner, by a mild chemical treatment using acetate. Acetate treatment allows a controllable increase of the CEC of montmorillonite up to 180 mequiv/100 g. The CEC of the clay is increasing for decreasing Zn content, with a slope of Delta[Zn/Delta[CEC] approximate to -2. X-ray powder diffraction analysis shows that the lamellar structure of the clay remains unaltered by the acetate treatment, while XPS substantiates the removal of Zn. H(+) uptake data show that the intrinsic protonation pK values and concentration of the variable charge sites ( SOH) are not modified by the acetate treatment. In contrast, the concentration of the permanent charge sites ( X(-)) increased linearly with Zn removal by acetate, leading to a significant H(+) and Cd(2+) uptake enhancement. A physical model is suggested where acetate removes Zn ions strongly bound in the clay, and this in turn modulates the permanent charge and the CEC of the clay

    Objectively assessed physical activity and subsequent health service use of UK adults aged 70 and over:a four to five year follow up study

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    OBJECTIVES: To examine the associations between volume and intensity of older peoples' physical activity, with their subsequent health service usage over the following four to five years.STUDY DESIGN: A prospective cohort design using baseline participant characteristics, objectively assessed physical activity and lower limb function provided by Project OPAL (Older People and Active Living). OPAL-PLUS provided data on numbers of primary care consultations, prescriptions, unplanned hospital admissions, and secondary care referrals, extracted from medical records for up to five years following the baseline OPAL data collection.PARTICIPANTS AND DATA COLLECTION: OPAL participants were a diverse sample of 240 older adults with a mean age of 78 years. They were recruited from 12 General Practitioner surgeries from low, middle, and high areas of deprivation in a city in the West of England. Primary care consultations, secondary care referrals, unplanned hospital admissions, number of prescriptions and new disease diagnoses were assessed for 213 (104 females) of the original 240 OPAL participants who had either consented to participate in OPAL-PLUS or already died during the follow-up period.RESULTS: In regression modelling, adjusted for socio-economic variables, existing disease, weight status, minutes of moderate-to-vigorous physical activity (MVPA) per day predicted subsequent numbers of prescriptions. Steps taken per day and MVPA also predicted unplanned hospital admissions, although the strength of the effect was reduced when further adjustment was made for lower limb function.CONCLUSIONS: Community-based programs are needed which are successful in engaging older adults in their late 70s and 80s in more walking, MVPA and activity that helps them avoid loss of physical function. There is a potential for cost savings to health services through reduced reliance on prescriptions and fewer unplanned hospital admissions.</p

    Gender perspectives on views and preferences of older people on exercise to prevent falls: a systematic mixed studies review

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    Background: To offer fall prevention exercise programs that attract older people of both sexes there is a need to understand both womens and mens views and preferences regarding these programs. This paper aims to systematically review the literature to explore any underlying gender perspectives or gender interpretations on older peoples views or preferences regarding uptake and adherence to exercise to prevent falls. Methods: A review of the literature was carried out using a convergent qualitative design based on systematic searches of seven electronic databases (PubMed, CINAHL, Amed, PsycINFO, Scopus, PEDro, and OTseeker). Two investigators identified eligible studies. Each included article was read by at least two authors independently to extract data into tables. Views and preferences reported were coded and summarized in themes of facilitators and barriers using a thematic analysis approach. Results: Nine hundred and nine unique studies were identified. Twenty five studies met the criteria for inclusion. Only five of these contained a gender analysis of mens and womens views on fall prevention exercises. The results suggests that both women and men see women as more receptive to and in more need of fall prevention messages. The synthesis from all 25 studies identified six themes illustrating facilitators and six themes describing barriers for older people either starting or adhering to fall prevention exercise. The facilitators were: support from professionals or family; social interaction; perceived benefits; a supportive exercise context; feelings of commitment; and having fun. Barriers were: practical issues; concerns about exercise; unawareness; reduced health status; lack of support; and lack of interest. Considerably more women than men were included in the studies. Conclusion: Although there is plenty of information on the facilitators and barriers to falls prevention exercise in older people, there is a distinct lack of studies investigating differences or similarities in older womens and mens views regarding fall prevention exercise. In order to ensure that fall prevention exercise is appealing to both sexes and that the inclusion of both men and women are encouraged, more research is needed to find out whether gender differences exists and whether practitioners need to offer a range of opportunities and support strategies to attract both women and men to falls prevention exercise.Funding Agencies|Swedish Research Council [2015-03481]; Strategic Research Programme in Care Sciences, Umea University; Karolinska Institute, Sweden; Umea University</p

    Loneliness, Social Isolation, and Objectively Measured Physical Activity in Rural-Living Older Adults

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    This cross-sectional, observational study examined whether objectively measured physical activity (PA) and specific activities are associated with loneliness and social isolation (SI) in rural-living older adults. A total of 112 participants (Mage = 72.8 [SD = 6.6], 51.8% female) from 23 villages in Wiltshire, United Kingdom, completed questionnaires, 7-day accelerometry, and activity diaries. Regression analysis was used to test associations between objectively measured light PA, moderate to vigorous PA, and total PA; loneliness; and SI from family, neighbors, or friends and to explore these associations using specific activities. Daily mean light, moderate to vigorous, and total PA were not associated with loneliness or SI. Volunteering, accompanying others, and sports/exercise were associated with lower SI from neighbors (odds ratio = 0.23, 95% CI [0.06, 0.91]), family (odds ratio = 0.39, 95% CI [0.22, 0.68]), and friends (odds ratio = 0.56, 95% CI [0.33, 0.97]), respectively. There were no associations between loneliness, SI, and objectively measured PA. The contribution of PA to loneliness and SI needs to be further investigated with larger and diverse samples of rural-living older adults

    Towards fast simulation of environmental fluid mechanics with multi-scale graph neural networks

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    Numerical simulators are essential tools in the study of natural fluid-systems, but their performance often limits application in practice. Recent machine-learning approaches have demonstrated their ability to accelerate spatio-temporal predictions, although, with only moderate accuracy in comparison. Here we introduce MultiScaleGNN, a novel multi-scale graph neural network model for learning to infer unsteady continuum mechanics in problems encompassing a range of length scales and complex boundary geometries. We demonstrate this method on advection problems and incompressible fluid dynamics, both fundamental phenomena in oceanic and atmospheric processes. Our results show good extrapolation to new domain geometries and parameters for long-term temporal simulations. Simulations obtained with MultiScaleGNN are between two and four orders of magnitude faster than those on which it was trained

    Quality of life in the fourth age: Exercise experiences of nursing home residents

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    Life in the Fourth Age has been typified as a time of continued functional decline and reduced quality of life. Exercise might positively affect this experience. This study explored the exercise experiences of nursing home residents age 86–99 years who participated in a 6-month exercise intervention. An interpretive phenomeno-logical approach was adopted. Twenty-one interviews were held with 14 residents at baseline and 7 residents at follow-up. Although their expectations were initially conservative, by the end of the intervention participants noted improved quality of life through better mobility, decreased fear of falling, and feelings of achievement and success. They valued the program as an opportunity to do something for themselves, to add something to their weekly routine, to meet other people, and to be more active generally. The professionalism of the exercise instructor appears to have been critical, balancing principles of safe and effective practice with the need to ensure that participants had fun in a supportive environment.</jats:p

    Exercise, Service and Support: Client Experiences of Physical Activity Referral Schemes(PARS)

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    Physical activity referral schemes (PARS) represent one of the most prevalent interventions in the fight against chronic illness such as coronary heart disease and obesity. Despite this, issues surrounding low retention and adherence continue to hinder the potential effectiveness of such schemes on public health. This article reports on the second stage of a larger investigation into client experiences of PARS focusing specifically on findings from five client-based focus groups and interviews with five Scheme Organisers. The resulting analysis reveals three main factors impacting participant perceptions of the quality of service and support received: the organisation of PARS provision, client engagement with the PARS community and the nature and extent of client support networks. The article demonstrates that staff have a considerable role to play in engaging clients in the PARS system and that Scheme Organisers should give serious thought to ensuring that clients have valuable and sustainable networks of support. Furthermore, it is suggested that Scheme Organisers need to facilitate a system in which staff are genuinely engaged with the needs of clients and are able to provide individualised programmes of physical activity
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