979 resultados para Independent mobility
Resumo:
The accurate experimental determination of the solubilities of antibiotics and anti-inflammatory drugs in supercritical fluids (SCFs) and correlations are essential for the development of supercritical technologies for the pharmaceuticals industry. In this work, the solubilities of penicillinG, penicillinV, flurbiprofen, ketoprofen, naproxen, ibuprofen, aspirin and diflunisal in supercritical carbon dioxide (SCCO2) were correlated using Peng-Robinson equation of state (PR EOS) with the modified Kwak and Mansoori mixing rules (mKM) and with Bartle model. The ability of mKM rules was compared against the conventional mixing rules of van der Waals in correlating the solubilities. In the present model, vapor pressure was considered as an adjustable parameter along with binary interactions parameters. In the proposed model, the constants used in the mixing rule, and vapor pressure expression coefficients are temperature independent. The optimization of these constants with experimental data gives binary interaction parameters along with vapor pressure correlations. Sublimation enthalpies were estimated with both the models compared with literature reported experimental values.
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Background Foot complications have been found to be predictors of mobility impairment and falls in community dwelling elderly patients. However, fewer studies have investigated the link between foot complications and mobility impairment in hospital in patient populations. The aim of this paper was to investigate the associations between mobility impairment and various foot complications in general inpatient populations. Methods Eligible participants were all adults admitted overnight, for any reason, into five diverse hospitals on one day; excluding maternity, mental health and cognitively impaired patients. Participants underwent a foot examination to clinically diagnose different foot complications; including foot wounds, infections, deformity, peripheral arterial disease and peripheral neuropathy. They were also surveyed on social determinant, medical history, self-care, footwear, foot complication history risk factors, and, mobility impairment defined as requiring a mobility aid for mobilisation prior to hospitalisation. Results Overall, 733 participants consented; mean(±SD) age 62(±19) years, 408 (55.8%) male, 172 (23.5%) diabetes. Mobility impairment was present in 242 (33.2%) participants; diabetes populations reported more mobility impairment than non-diabetes populations (40.7% vs 30.9%, p < 0.05). In a backwards stepwise multivariate analysis, and controlling for other risk factors, those people with mobility impairment were independently associated with increasing years of age (OR = 1.04 (95% CI) (1.02-1.05)), male gender (OR = 1.7 (1.2-2.5)), being born in Australia (OR = 1.7 (1.1-2.8), vision impairment (2.0 (1.2-3.1)), peripheral neuropathy (OR = 3.1 (2.0-4.6) and foot deformity (OR = 2.0 (1.3-3.0). Conclusions These findings support the results of other large studies investigating community dwelling elderly patients that peripheral neuropathy and foot deformity are independently associated with mobility impairment and potentially falls. Furthermore the findings suggest routine clinical diagnosis of foot complications as defined by national diabetic foot guidelines were sufficient to determine these associated foot complication risk factors for mobility impairment. Further research is required to establish if these foot complication risk factors for mobility impairment are predictors of actual falls in the inpatient environment.
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Magnetotransport measurements in pulsed fields up to 15 T have been performed on mercury cadmium telluride (Hg1-xCdxTe, x similar to 0.2) bulk as well as liquid phase epitaxially grown samples to obtain the resistivity and conductivity tensors in the temperature range 220-300 K. Mobilities and densities of various carriers participating in conduction have been extracted using both conventional multicarrier fitting (MCF) and mobility spectrum analysis. The fits to experimental data, particularly at the highest magnetic fields, were substantially improved when MCF is applied to minimize errors simultaneously on both resistivity and conductivity tensors. The semiclassical Boltzmann transport equation has been solved without using adjustable parameters by incorporating the following scattering mechanisms to fit the mobility: ionized impurity, polar and nonpolar optical phonons, acoustic deformation potential, and alloy disorder. Compared to previous estimates based on the relaxation time approximation with outscattering only, polar optical scattering and ionized impurity scattering limited mobilities are shown to be larger due to the correct incorporation of the inscattering term taking into account the overlap integrals in the valence band.
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X-ray powder diffraction along with differential thermal analysis carried out on the as-quenched samples in the 3BaO-3TiO(2)-B2O3 system confirmed their amorphous and glassy nature, respectively. The dielectric constants in the 1 kHz-1 MHz frequency range were measured as a function of temperature (323-748 K). The dielectric constant and loss were found to be frequency independent in the 323-473 K temperature range. The temperature coefficient of dielectric constant was estimated using Havinga's formula and found to be 16 ppm K-1. The electrical relaxation was rationalized using the electric modulus formalism. The dielectric constant and loss were 17 +/- 0.5 and 0.005 +/- 0.001, respectively at 323 K in the 1 kHz-1 MHz frequency range which may be of considerable interest to capacitor industry.
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People with disabilities (PWD) experience difficulties in accessing the transport system (including both infrastructure and services) to meet their needs for health care, employment and other activities. Our research shows that lack of access to the journeys needed for these purposes is a more significant barrier in low and middle income countries than in high income countries, and results in inadequate health care, rehabilitation and access to education and employment. At the same time, the existing transport system in low and middle income countries presents much higher road crash risks than in high income countries. By combining the principles and methods of Road Safety Audit and disability access, and adapting these Western approaches to a low/middle income country context, we have worked with Handicap International Cambodia to develop a Journey Access Tool (JAT) for use by disabled peoples’ organisations (DPOs), people with a disability and other key stakeholders. A key element of the approach is that it involves the participation of PWD on the journeys that they need to take, and it identifies infrastructure and service improvements that should be prioritised in order to facilitate access to these journeys. The JAT has been piloted in Cambodia with a range of PWD. This presentation will outline the design of the JAT and the results of the pilot studies. The information gained thus far strongly suggests that the JAT is a valuable and cost-effective approach that can be used by DPOs and professionals to identify barriers to access and prioritise the steps needed to address them.
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Although the importance of clathrin- and caveolin-independent endocytic pathways has recently emerged, key aspects of these routes remain unknown. Using quantitative ultrastructural approaches, we show that clathrin-independent carriers (CLICs) account for approximately three times the volume internalized by the clathrin-mediated endocytic pathway, forming the major pathway involved in uptake of fluid and bulk membrane in fibroblasts. Electron tomographic analysis of the 3D morphology of the earliest carriers shows that they are multidomain organelles that form a complex sorting station as they mature. Proteomic analysis provides direct links between CLICs, cellular adhesion turnover, and migration. Consistent with this, CLIC-mediated endocytosis of key cargo proteins, CD44 and Thy-1, is polarized at the leading edge of migrating fibroblasts, while transient ablation of CLICs impairs their ability to migrate. These studies provide the first quantitative ultrastructural analysis and molecular characterization of the major endocytic pathway in fibroblasts, a pathway that provides rapid membrane turnover at the leading edge of migrating cells.
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Taking as its starting point a remark by Turner Prize nominee Yinka Shonibare that disability arts is “the last avant garde”, this panel focuses on the role of aesthetic experimentation in disability arts and the possible rethinking of the relationship between avant-garde aesthetic strategies and inclusive arts. Points of connection between the avant-garde and disability arts include a rejection of traditional aesthetic forms, the development of aesthetic strategies appropriate to non-normative bodies, politics and populations and the implications of these ideas for the conference themes. This panel is intended as a facilitated discussion involving researchers and artists undertaking work in this area. The panel will begin with some brief provocations reflecting on the implication of Shonibare’s comment. For example, Gerard Goggin will discuss three projects by Antoni Abad with artists and activists with disability in Barcelona, Geneva and Montreal as part of Abad’s Megaphone project, a decade-long, global digital art project. Bree Hadley will speak on performative interventions in public space, performance art, live art, activism and culture hacking by artists with disabilities, such as pwd's online performances, and artist’s performative responses to the austerity agenda in the US, UK, and Australasia. Eddie, Lachlan and Sarah will discuss ideas arising from their work on the project Beyond Access: The Creative Case for Inclusive Arts, which involved research with six Melbourne-based artists/artistic companies with disability, supported by Arts Access Victoria. Chair: Dr Eddie Paterson (School of Culture and Communication, Faculty of Arts, University of Melbourne) Dr Bree Hadley (Creative Industries, QUT) Professor Gerard Goggin (Professor of Media and Communication and ARC Future Fellow, University of Sydney) Dr Lachlan MacDowall (Head, Centre for Cultural Partnerships, University of Melbourne). Sarah Austin (PhD candidate, Theatre/Centre for Cultural Partnerships, VCA and MCM) Artists (tbc, based on existing relationships with artists developed in the Beyond Access research).
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Emissions of coal combustion fly ash through real scale ElectroStatic Precipitators (ESP) were studied in different coal combustion and operation conditions. Sub-micron fly-ash aerosol emission from a power plant boiler and the ESP were determined and consequently the aerosol penetration, as based on electrical mobility measurements, thus giving thereby an indication for an estimate on the size and the maximum extent that the small particles can escape. The experimentals indicate a maximum penetration of 4% to 20 % of the small particles, as counted on number basis instead of the normally used mass basis, while simultaneously the ESP is operating at a nearly 100% collection efficiency on mass basis. Although the size range as such seems to appear independent of the coal, of the boiler or even of the device used for the emission control, the maximum penetration level on the number basis depends on the ESP operating parameters. The measured emissions were stable during stable boiler operation for a fired coal, and the emissions seemed each to be different indicating that the sub-micron size distribution of the fly-ash could be used as a specific characteristics for recognition, for instance for authenticity, provided with an indication of known stable operation. Consequently, the results on the emissions suggest an optimum particle size range for environmental monitoring in respect to the probability of finding traces from the samples. The current work embodies also an authentication system for aerosol samples for post-inspection from any macroscopic sample piece. The system can comprise newly introduced new devices, for mutually independent use, or, for use in a combination with each other, as arranged in order to promote the sampling operation length and/or the tag selection diversity. The tag for the samples can be based on naturally occurring measures and/or added measures of authenticity in a suitable combination. The method involves not only military related applications but those in civil industries as well. Alternatively to the samples, the system can be applied to ink for note printing or other monetary valued papers, but also in a filter manufacturing for marking fibrous filters.
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Among the societal and health challenges of population ageing is the continued transport mobility of older people who retain their driving licence, especially in highly car-dependent societies. While issues surrounding loss of a driving licence have been researched, less attention has been paid to variations in physical travel by mode among the growing proportion of older people who retain their driving licence. It is unclear how much they reduce their driving with age, the degree to which they replace driving with other modes of transport, and how this varies by age and gender. This paper reports research conducted in the state of Queensland, Australia, with a sample of 295 older drivers (>60 years). Time spent driving is considerably greater than time spent as a passenger or walking across age groups and genders. A decline in travel time as a driver with increasing age is not redressed by increases in travel as a passenger or pedestrian. The patterns differ by gender, most likely reflecting demographic and social factors. Given the expected considerable increase in the number of older women in particular, and their reported preference not to drive alone, there are implications for policies and programmes that are relevant to other car-dependent settings. There are also implications for the health of older drivers, since levels of walking are comparatively low.
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For achieving efficient fusion energy production, the plasma-facing wall materials of the fusion reactor should ensure long time operation. In the next step fusion device, ITER, the first wall region facing the highest heat and particle load, i.e. the divertor area, will mainly consist of tiles based on tungsten. During the reactor operation, the tungsten material is slowly but inevitably saturated with tritium. Tritium is the relatively short-lived hydrogen isotope used in the fusion reaction. The amount of tritium retained in the wall materials should be minimized and its recycling back to the plasma must be unrestrained, otherwise it cannot be used for fueling the plasma. A very expensive and thus economically not viable solution is to replace the first walls quite often. A better solution is to heat the walls to temperatures where tritium is released. Unfortunately, the exact mechanisms of hydrogen release in tungsten are not known. In this thesis both experimental and computational methods have been used for studying the release and retention of hydrogen in tungsten. The experimental work consists of hydrogen implantations into pure polycrystalline tungsten, the determination of the hydrogen concentrations using ion beam analyses (IBA) and monitoring the out-diffused hydrogen gas with thermodesorption spectrometry (TDS) as the tungsten samples are heated at elevated temperatures. Combining IBA methods with TDS, the retained amount of hydrogen is obtained as well as the temperatures needed for the hydrogen release. With computational methods the hydrogen-defect interactions and implantation-induced irradiation damage can be examined at the atomic level. The method of multiscale modelling combines the results obtained from computational methodologies applicable at different length and time scales. Electron density functional theory calculations were used for determining the energetics of the elementary processes of hydrogen in tungsten, such as diffusivity and trapping to vacancies and surfaces. Results from the energetics of pure tungsten defects were used in the development of an classical bond-order potential for describing the tungsten defects to be used in molecular dynamics simulations. The developed potential was utilized in determination of the defect clustering and annihilation properties. These results were further employed in binary collision and rate theory calculations to determine the evolution of large defect clusters that trap hydrogen in the course of implantation. The computational results for the defect and trapped hydrogen concentrations were successfully compared with the experimental results. With the aforedescribed multiscale analysis the experimental results within this thesis and found in the literature were explained both quantitatively and qualitatively.
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Aging in a country village This dissertation examines what kind of environment of aging a small country village is, who elderly villagers are and what kind of everyday life they have. The qualitative material gathered through ethnographic field work at a village situated in Southern Finland consists of a field work diary and 34 interviews of elderly villagers. The dissertation is based on social gerontology and village research. The key concepts are: the environment of aging; locality and local identity; and way of life. The village is examined as a social and physical environment of aging. Difficulties regarding mobility are the biggest challenges for elderly villagers in their everyday life. The social environment of aging is constructed by historical, cultural and local factors. The village community is formed by many small sub-communities. An elderly villager s status in a village community and her/his social competence affect the formation of her/his social network and the quality of her/his environment of aging. The dissertation examines the local identities of older villagers and their relationships to the village. The local identities can be based on the village, memories or on many places, or a place and places may not be of great importance for a person s identity. The local identity of an older villager affects her/his experiences of living in the village and her/his future plans to move away from the village. The everyday life of an older villager is constructed by rhythms, routines and repetitions. However, there are differences between how everyday lives are arranged among elderly villagers, which are explained by the concept of a way of life. Four ways of life were found. Nature and its importance are a background to all four ways of life. A traditional way of life is based on continuity and hard work, a family-oriented way of life on family members and relatives. A mobile way of life is characterized by symbolic and concrete mobility. An original way of life is marked by independent loneliness . In practice, a person s way of life is always constructed by two or many ways of life.
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The stability of scheduled multiaccess communication with random coding and independent decoding of messages is investigated. The number of messages that may be scheduled for simultaneous transmission is limited to a given maximum value, and the channels from transmitters to receiver are quasistatic, flat, and have independent fades. Requests for message transmissions are assumed to arrive according to an i.i.d. arrival process. Then, we show the following: (1) in the limit of large message alphabet size, the stability region has an interference limited information-theoretic capacity interpretation, (2) state-independent scheduling policies achieve this asymptotic stability region, and (3) in the asymptotic limit corresponding to immediate access, the stability region for non-idling scheduling policies is shown to be identical irrespective of received signal powers.
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Serum parathyroid hormone (PTH) and vitamin D are the major regulators of extracellular calcium homeostasis. The inverse association between PTH and vitamin D and the common age-related elevation of the PTH concentration are well known phenomena. However, the confounding or modifying factors of this relationship and their impact on the response of PTH levels to vitamin D supplementation need further investigation. Clinical conditions such as primary hyperparathyroidism (PHPT), renal failure and vitamin D deficiency, characterized by an elevation of the PTH concentration, have been associated with impaired long-term health outcomes. Curative treatments for these conditions have also been shown to decreases PTH concentration and attenuate some of the adverse health effects. In PHPT it has also been commonly held that hypercalcaemia, the other hallmark of the disease, is the key mediator of the adverse health outcomes. In chronic kidney disease the systemic vascular disease has been proposed to have the most important impact on general health. Some evidence also indicates that vitamin D may have significant extraskeletal actions. However, the frank elevation of PTH concentration seen in advanced PHPT and in end-stage renal failure have also been suggested to be at least partly causally related to an increased risk of death as well as cognitive dysfunction. However, the exact mechanisms have remained unclear. Furthermore, the predictive value of elevated PTH in unselected older populations has been less well studied. The studies presented in this thesis investigated the impact of age and mobility on the responses of PTH levels to vitamin D deficiency and supplementation. Furthermore, the predictive value of PTH for long-term survival and cognitive decline was addressed in an unselected population of older people. The hypothesis was that age and chronic immobility are related to a persistently blunted elevation of PTH concentration, even in the presence of chronic vitamin D deficiency, and to attenuated responses of PTH to vitamin D supplementation. It was also further hypothesized that a slightly elevated or even high-normal PTH concentration is an independent indicator of an increased risk of death and cognitive decline in the general aged population. The data of this thesis are based on three samples: a meta-analysis of published vitamin D supplementation trials, a randomized placebo controlled six-month vitamin D supplementation trial, and a longitudinal prospective cohort study on a general aged population. Based on a PubMed search, a meta-analysis of 52 clinical trials with 6 290 adult participants was performed to evaluate the impact of age and immobility on the responses of PTH to 25-OHD levels and vitamin D supplementation. A total of 218 chronically immobile, very old inpatients were also enrolled into a vitamin D supplementation trial. Mortality data for these patients was also collected after a two-year follow-up. Finally, data from the Helsinki Aging Study, which followed three random age cohorts (75, 80 and 85 years) until death in almost all subjects, was used to evaluate the predictive value of PTH for long-term survival and cognitive decline. This series of studies demonstrated that in older people without overt renal failure or severe hypercalcaemia, serum 25-OHD and PTH were closely associated, but this relationship was also affected by age and immobility. Furthermore, a substantial proportion of old chronically bedridden patients did not respond to vitamin D deficiency by elevating PTH, and the effect of a high-dose (1200 IU/d) six-month cholecalciferol supplementation on the PTH concentration was minor. This study demonstrated longitudinally for the first time that the blunted PTH also persisted over time. Even a subtle elevation of PTH to high-normal levels predicted impaired long-term health outcomes. Slightly elevated PTH concentrations indicated an increased risk of clinically significant cognitive decline and death during the last years of life in a general aged population. This association was also independent of serum ionized calcium (Ca2+) and the estimated glomerular filtration rate (GFR). A slightly elevated PTH also indicated impaired two-year survival during the terminal years of frail elderly subjects independently of Ca2+, GFR, and of 25-OHD levels. The interplay between PTH and vitamin D in the regulation of calcium homeostasis is more complex than has been generally considered. In addition to muskuloskeletal health parathyroid hormone is also related to the maintenance of other important domains of health in old age. Higher PTH concentrations, even within conventional laboratory reference ranges, seem to be an independent indicator of an increased risk of all-cause and of cardiovascular mortality, independently of established cardiovascular risk factors, disturbances in mineral metabolism, and renal failure. Limited and inconsistent evidence supports the role of vitamin D deficiency-related lack of neuroprotective effects over the causal association between PTH and impaired cognitive functions. However, the causality of these associations remains unclear. The clinical implications of the observed relationships remain to be elucidated by future studies interfering with PTH concentrations, especially by long-term interventions to reduce PTH.
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Sesbania mosaic virus (SeMV),a single-strand positive-sense RNA plant virus, belongs to the genus Sobemoviruses. Mechanism of replication in Sobemoviruses is poorly understood. In the present study, SeMV RNA-dependent RNA polymerase (RdRp) was overexpressed and purified as a thioredoxin-tagged protein. The recombinant SeMV RdRp could synthesize RNA from genomic or subgenomic RNA templates, even in the absence ofthe protein primer, VPg. Analysis of the product indicated that it was double-stranded and that the mode of initiation was de novo. Mutational analysis of the 3' UTR of subgenomic RNA revealed that a stem-loop structure at the 3' end was important. Further, analysis of this stem-loop showed that the SeMV RdRp was capable of recognizing stem-loop structures of various lengths and forms. These results demonstrate that the SeMV RdRp is capable of primer-independent RNAsynthesis in vitro. (C) 2010 Elsevier Inc. All rights reserved.