53 resultados para Physical environment and pipelines


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We present new optical and near-infrared (NIR) photometry and spectroscopy of the Type IIP supernova (SN), SN 2004et. In combination with already published data, this provides one of the most complete studies of optical and NIR data for any Type IIP SN from just after explosion to +500 d. The contribution of the NIR flux to the bolometric light curve is estimated to increase from 15 per cent at explosion to around 50 per cent at the end of the plateau and then declines to 40 per cent at 300 d. SN 2004et is one of the most luminous IIP SNe which has been well studied and characterized, and with a luminosity of log L = 42.3 erg s-1 and a 56Ni mass of 0.06 +/- 0.04 M-circle dot, it is two times brighter than SN 1999em. We provide parametrized bolometric corrections as a function of time since explosion for SN 2004et and three other IIP SNe that have extensive optical and NIR data. These can be used as templates for future events in optical and NIR surveys without full wavelength coverage. We compare the physical parameters of SN 2004et with those of other well-studied IIP SNe and find that the kinetic energies span a range of 1050-1051 erg. We compare the ejected masses calculated from hydrodynamic models with the progenitor masses and limits derived from pre-discovery images. Some of the ejected mass estimates are significantly higher than the progenitor mass estimates, with SN 2004et showing perhaps the most serious mass discrepancy. With the current models, it appears difficult to reconcile 100 d plateau lengths and high expansion velocities with the low ejected masses of 5-6 M-circle dot implied from 7-8 M-circle dot progenitors. The nebular phase is studied using very late-time Hubble Space Telescope photometry, along with optical and NIR spectroscopy. The light curve shows a clear flattening at 600 d in the optical and the NIR, which is likely due to the ejecta impacting on circumstellar material. We further show that the [O i] 6300, 6364 A line strengths in the nebular spectra of four Type IIP SNe imply ejected oxygen masses of 0.5-1.5 M-circle dot.

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Public participation in the planning system is well established in both academic and practice based research. The failure to engage the 'public' effectively has resulted in costly and unpopular decisions and produced a debate about how, when and with whom to participate. Children have tended to be marginal or ignored in land use planning but this paper suggests that, given the right techniques, they can be articulate, reasonable and clear thinkers about the type of environment they live in and how it should change. It draws on Mental Mapping and Environmental Affordance methodologies to show how eleven year old children can read their neighbourhood, identify barriers and highlight the benefits they extract from a deeper cognitive understating of their place. The paper concludes by suggesting that these techniques are transferable globally, especially where literacy and numeracy is weak and where planners reliance on formalised consultations reflect the interests of state and economic elites rather than the wider population.

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The unique properties of nanomaterials, in particular gold nanoparticles (GNPs) have applications for a wide range of biomedical applications. GNPs have been proposed as novel radiosensitizing agents due to their strong photoelectric absorption coefficient. Experimental evidence supporting the application of GNPs as radiosensitizing agents has been provided from extensive in vitro investigation and a relatively limited number of in vivo studies. Whilst these studies provide experimental evidence for the use of GNPs in combination with ionising radiation, there is an apparent disparity between the observed experimental findings and the level of radiosensitization predicted by mass energy absorption and GNP concentration. This review summarises experimental findings and attempts to highlight potential underlying biological mechanisms of response in GNP radiosensitization.

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Despite several decades of decline, cardiovascular diseases are still the most common causes of death in Western societies. Sedentary living and high fat diets contribute to the prevalence of cardiovascular diseases. This paper analyses the trade-offs between lifestyle choices defined in terms of diet, physical activity, cost, and risk of cardiovascular disease that a representative sample of the population of Northern Ireland aged 40-65 are willing to make. Using computer assisted personal interviews, we survey 493 individuals at their homes using a Discrete Choice Experiment (DCE) questionnaire administered between February and July 2011 in Northern Ireland. Unlike most DCE studies for valuing public health programs, this questionnaire uses a tailored exercise, based on the individuals’ baseline choices. A “fat screener” module in the questionnaire links personal cardiovascular disease risk to each specific choice set in terms of dietary constituents. Individuals are informed about their real status quo risk of a fatal cardiovascular event, based on an initial set of health questions. Thus, actual risks, real diet and exercise choices are the elements that constitute the choice task. Our results show that our respondents are willing to pay for reducing mortality risk and, more importantly, are willing to change physical exercise and dietary behaviours. In particular, we find that to improve their lifestyles, overweight and obese people would be more likely to do more physical activity than to change their diets. Therefore, public policies aimed to target obesity and its related illnesses in Northern Ireland should invest public money in promoting physical activity rather than healthier diets.

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Poly(vinyl alcohol)-tetrahydroxyborate (PVA-THB) hydrogels are dilatant formulations with potential for topical wound management. To support this contention, the physical properties, rheological behaviour and component release of candidate formulations were investigated. Oscillatory rheometry and texture profile analysis were used at room temperature and 37 °C. Results showed that it was possible to control the rheological and textural properties by altering component concentration and modifying the type of PVA polymer used. Hydrogels made using PVA grades with higher degrees of hydrolysis displayed favourable characteristics from a wound healing perspective. In vitro release of borate and PVA were assessed in order to evaluate potential clinical dosing of free species originating from the hydrogel structure. Component diffusion was influenced by both concentration and molecular weight, where relevant, with up to 5% free PVA cumulative release observed after 30 min. The results of this study demonstrated the importance of poly(vinyl alcohol) selection for ensuring appropriate gel formation in PVA-THB hydrogels. The benefits of higher degrees of hydrolysis, in particular, included lower excipient release and reduced bioadhesion. The unique physical characteristics of these hydrogels make them an appealing delivery vehicle for chronic and acute wound management purposes.

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Fruit and vegetable (FV) intake, which is often low in older people, may be associated with improved muscle strength and physical function. However, there is a shortage of intervention trial evidence to support this. The current study examined the effect of increased FV consumption on measures of muscle strength and physical function among healthy, free-living older adults. A randomized controlled intervention study was undertaken. Eighty-three participants aged 65-85 years, habitually consuming =2 portions of FV/day, were randomised to continue their normal diet (=2 portions/day), or to consume =5 portions of FV/day for 16 weeks. FV were delivered to all participants each week, free of charge. Compliance was monitored at baseline, 6, 12 and 16 weeks by diet history and by measuring biomarkers of micronutrient status. Grip strength was measured by a hand-held dynamometer, while lower-extremity physical function was assessed by performance-based measures. Eighty-two participants completed the intervention. The 5 portions/day group showed greater change in daily FV consumption compared to the 2 portions/day group (P?

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Background: Physical activity appears important contributor for healthy aging, including cognitive function. However, it is unclear whether late life physical activity alone is beneficial to cognitive function. We performed a systematic review to examine the effect of late life physical activity in maintaining cognitive function in older persons.
Methods: Search Strategy and Selection criteria: The search sources consisted of PubMed, MEDLINE, CINAHL, Cochrane Controlled Trials Register (CENTRAL), and the University of Washington Medical School Library Database between July 15, 2011 and August 15, 2012 with language restricted to English. Studies that were published in journals on or after January 2000 with participants older than 60 years of age were reviewed. Randomized controlled trials including at least 30 participants and lasting for at least 6 months and all observational studies of at least 100 participants and lasting at least 1 year in duration were eligible for inclusion Two reviewers assessed the applicability and results of these studies.
Results: Twenty-six studies fulfilling the inclusion criteria are included. Twenty-one studies reported that late life physical activity resulted in maintenance or enhancement of cognitive function. Three studies reported a dose-response relationship between physical activity and cognition.
Conclusions: Late life physical activity is beneficial for cognitive function in the elderly. However, the majority of the evidence is of medium quality with moderate risk of bias. Larger, randomized controlled trials are needed to better define the association between late life physical activity and cognitive function. Further research is required to determine which types of exercise have the greatest benefits on specific cognitive domains. Despite these caveats, current data are sufficient to recommend that moderate level, late life physical activity may be an effective method to improve cognitive function and delay the onset and progression of cognitive disease in the elderly.

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It is now recognised that inactive lifestyles underpin much of the disease burden evident in the richer nations of the world. Indeed, the WHO has identified physical inactivity as a 'global public health problem' and has established minimum physical activity (PA) targets for people at different stages of the life-course. Yet, according to WHO, just under 1/3 of working age adults across the globe meet those targets and it is not at all clear how the disjunction between the recommendations of policy makers and the behaviour of ordinary people might be surmounted. Using an opportunity to examine the impact of an urban regeneration project on community residents in East Belfast (Northern Ireland) this paper examines the views of some 113 people on how to increase rates of PA in an area of multiple deprivation. The results of the analysis suggest that lay people rarely consider PA as a discrete issue, or one that centres on individuals and their motivation, but rather as one component in a complex web of concerns, processes and events that include such things as the actions of neighbours and relatives, material and political environments, vandalism, violence, and the weather. We explore and unravel the nature of those concerns using novel methods of content analysis that generate 'issue webs'. Particular attention is paid to the ways in which lay people conceptualize 'activity' and to the manner in which they point to ways of encouraging activity that are rooted in everyday life rather than in the corpocentric, agent-centred and often sport dominated strategies favoured by local policy makers. Our results support those who argue that interventions to increase rates of PA need to move beyond behavioural approaches that focus on individuals and consider the social, political and material contexts in which 'activity' occurs.