908 resultados para balance energía


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Balance maintenance relies on a complex interplay between many different sensory modalities. Although optimal multisensory processing is thought to decline with ageing, inefficient integration is particularly associated with falls in older adults. We investigated whether improved balance control, following a novel balance training intervention, was associated with more efficient multisensory integration in older adults, particularly those who have fallen in the past. Specifically, 76 healthy and fall-prone older adults were allocated to either a balance training programme conducted over 5 weeks or to a passive control condition. Balance training involved a VR display in which the on-screen position of a target object was controlled by shifts in postural balance on a Wii balance board. Susceptibility to the sound-induced flash illusion, before and after the intervention (or control condition), was used as a measure of multisensory function. Whilst balance and postural control improved for all participants assigned to the Intervention group, improved functional balance was correlated with more efficient multisensory processing in the fall-prone older adults only. Our findings add to growing evidence suggesting important links between balance control and multisensory interactions in the ageing brain and have implications for the development of interventions designed to reduce the risk of falls.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This work proposes a novel approach to compute transonic limit-cycle oscillations using high-fidelity analysis. Computational-Fluid-Dynamics based harmonic balance methods have proven to be efficient tools to predict periodic phenomena. This paper’s contribution is to present a new methodology to determine the unknown frequency of oscillations, enabling harmonic balance methods to accurately capture limit-cycle oscillations; this is achieved by defining a frequency-updating procedure based on a coupled computational-fluid-dynamics/computational-structural-dynamics harmonic balance formulation to find the limit-cycle oscillation condition. A pitch/plunge airfoil and delta wing aerodynamic and respective linear structural models are used to validate the new method against conventional time-domain simulations. Results show consistent agreement between the proposed and time-marching methods for both limit-cycle oscillation amplitude and frequency while producing at least a one-order-of-magnitude reduction in computational time.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

African evangelical/Pentecostal/charismatic (EPC) Christians-previously dismissed by scholars as apolitical-are becoming increasingly active socially and politically. This chapter presents a case study of an EPC congregation in Harare. It demonstrates how the congregation provides short-term human security by responding to the needs of the poor, while at the same time creating space where people can develop the "self-expression values" necessary for long-term human security. The case study also demonstrates that even under authoritarian states, religious actors can actively choose to balance the immediate demands of short-term human security with the sometimes competing demands of long-term human security. Policymakers can benefit from a greater understanding of how religious actors strike this balance and from a greater appreciation of the variability, flexibility, and religious resources of EPC Christians in such contexts.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Introduction: In this cohort study, we explored the relationship between fluid balance, intradialytic hypotension and outcomes in critically ill patients with acute kidney injury (AKI) who received renal replacement therapy (RRT).

Methods: We analysed prospectively collected registry data on patients older than 16 years who received RRT for at least two days in an intensive care unit at two university-affiliated hospitals. We used multivariable logistic regression to determine the relationship between mean daily fluid balance and intradialytic hypotension, both over seven days following RRT initiation, and the outcomes of hospital mortality and RRT dependence in survivors.

Results: In total, 492 patients were included (299 male (60.8%), mean (standard deviation (SD)) age 62.9 (16.3) years); 251 (51.0%) died in hospital. Independent risk factors for mortality were mean daily fluid balance (odds ratio (OR) 1.36 per 1000 mL positive (95% confidence interval (CI) 1.18 to 1.57), intradialytic hypotension (OR 1.14 per 10% increase in days with intradialytic hypotension (95% CI 1.06 to 1.23)), age (OR 1.15 per five-year increase (95% CI 1.07 to 1.25)), maximum sequential organ failure assessment score on days 1 to 7 (OR 1.21 (95% CI 1.13 to 1.29)), and Charlson comorbidity index (OR 1.28 (95% CI 1.14 to 1.44)); higher baseline creatinine (OR 0.98 per 10 mu mol/L (95% CI 0.97 to 0.996)) was associated with lower risk of death. Of 241 hospital survivors, 61 (25.3%) were RRT dependent at discharge. The only independent risk factor for RRT dependence was pre-existing heart failure (OR 3.13 (95% CI 1.46 to 6.74)). Neither mean daily fluid balance nor intradialytic hypotension was associated with RRT dependence in survivors. Associations between these exposures and mortality were similar in sensitivity analyses accounting for immortal time bias and dichotomising mean daily fluid balance as positive or negative. In the subgroup of patients with data on pre-RRT fluid balance, fluid overload at RRT initiation did not modify the association of mean daily fluid balance with mortality.

Conclusions: In this cohort of patients with AKI requiring RRT, a more positive mean daily fluid balance and intradialytic hypotension were associated with hospital mortality but not with RRT dependence at hospital discharge in survivors.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Over 1 million km2 of seafloor experience permanent low-oxygen conditions within oxygen minimum zones (OMZs). OMZs are predicted to grow as a consequence of climate change, potentially affecting oceanic biogeochemical cycles. The Arabian Sea OMZ impinges upon the western Indian continental margin at bathyal depths (150 - 1500 m) producing a strong depth dependent oxygen gradient at the sea floor. The influence of the OMZ upon the short term processing of organic matter by sediment ecosystems was investigated using in situ stable isotope pulse chase experiments. These deployed doses of 13C:15N labeled organic matter onto the sediment surface at four stations from across the OMZ (water depth 540 - 1100 m; [O2] = 0.35 - 15 μM). In order to prevent experimentally anoxia, the mesocosms were not sealed. 13C and 15N labels were traced into sediment, bacteria, fauna and 13C into sediment porewater DIC and DOC. However, the DIC and DOC flux to the water column could not be measured, limiting our capacity to obtain mass-balance for C in each experimental mesocosm. Linear Inverse Modeling (LIM) provides a method to obtain a mass-balanced model of carbon flow that integrates stable-isotope tracer data with community biomass and biogeochemical flux data from a range of sources. Here we present an adaptation of the LIM methodology used to investigate how ecosystem structure influenced carbon flow across the Indian margin OMZ. We demonstrate how oxygen conditions affect food-web complexity, affecting the linkages between the bacteria, foraminifera and metazoan fauna, and their contributions to benthic respiration. The food-web models demonstrate how changes in ecosystem complexity are associated with oxygen availability across the OMZ and allow us to obtain a complete carbon budget for the stationa where stable-isotope labelling experiments were conducted.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: Falls and fall-related injuries are symptomatic of an aging population. This study aimed to design, develop, and deliver a novel method of balance training, using an interactive game-based system to promote engagement, with the inclusion of older adults at both high and low risk of experiencing a fall.

STUDY DESIGN: Eighty-two older adults (65 years of age and older) were recruited from sheltered accommodation and local activity groups. Forty volunteers were randomly selected and received 5 weeks of balance game training (5 males, 35 females; mean, 77.18 ± 6.59 years), whereas the remaining control participants recorded levels of physical activity (20 males, 22 females; mean, 76.62 ± 7.28 years). The effect of balance game training was measured on levels of functional balance and balance confidence in individuals with and without quantifiable balance impairments.

RESULTS: Balance game training had a significant effect on levels of functional balance and balance confidence (P < 0.05). This was further demonstrated in participants who were deemed at high risk of falls. The overall pattern of results suggests the training program is effective and suitable for individuals at all levels of ability and may therefore play a role in reducing the risk of falls.

CONCLUSIONS: Commercial hardware can be modified to deliver engaging methods of effective balance assessment and training for the older population.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article combines practitioner insight and research evidence to chart how principles of partnership and paramountcy have led to birth family contact becoming the expected norm following contested adoption from care in Northern Ireland. The article highlights how practice has adapted to the delay in proposed reforms to adoption legislation resulting in the evolution of increasingly open adoption practices. Adoption represents an irrevocable transfer of parental responsibility from birth to adoptive parents and achieves permanence and legal security for children in care who cannot return to their birth family. Its enduring effect, however, makes public adoption a contentious field of child welfare practice, particularly when contested by birth parents. This article explores how post-adoption contact may be viewed as reconciling the uneasy interface between paramountcy principles and parental rights to respect for family life. The article highlights the complexity of adoptive kinship relationships following contested adoption from care, and how contact presents unique challenges that mitigate against meaningful and sustainable connections between the child and their birth relatives. In conclusion, a call is made for sensitive negotiation and support of contact arrangements, and the development of practice models that are informed by an understanding of the workings of adoptive kinship.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Positive psychology, an emergent branch of scholarship concerned with wellbeing and flourishing, initially defined itself by a focus on “positive” emotions and qualities. However, critics soon pointed out that this binary logic—classifying phenomena as either positive or negative, and valorising the former while disparaging the latter—could be problematic. For example, apparently positive qualities can be harmful to wellbeing in certain circumstances, while ostensibly dysphoric emotional states may on occasion promote flourishing. Responding to these criticisms, over recent years a more nuanced “second wave” of positive psychology has been developing, in which wellbeing is recognized as involving a dialectical balance of light and dark aspects of life. This article introduces this emergent second wave, arguing that it is characterized by four dialectical principles. First, the principle of appraisal states that it is difficult to categorically identify phenomena as either positive or negative, since such appraisals are fundamentally contextually dependent. Second, the principle of co-valence holds that many states and qualities at the heart of flourishing, such as love, are actually a complex blend of light and dark elements. Third, the principle of complementarity posits that not only are such phenomena co-valenced, but that their dichotomous elements are in fact co-creating, two intertwined sides of the same coin. Finally, the principle of evolution allows us to understand second-wave positive psychology as itself being an example of a dialectical process. This article is published as part of a collection entitled “On balance: lifestyle, mental health and wellbeing”.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Dissertação mest., Gestão da água e da costa, Universidade do Algarve, 2007

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aims of this work were to deepen the knowledge on the physiology of bract abscission in Bougainvillea spectabilis ‘Killie Campbell’ plants, in what relates to respiration and carbon balance. Using the effects induced by Silver Thiosulphate (STS) and/or Naphtalene Acetic Acid (NAA, at high concentration: 500 mg.l-1) on bract abscission under interior conditions, the relationship between bract survival time (longevity) and, respiration rate or carbohydrate levels, was investigated. Treatments that included NAA were the ones that reduced significantly bract abscission. Unexpectedly, the higher the levels of bract soluble and total carbohydrates, measured at day 10 postproduction (PP), the higher the abscission of bracts. These results show, for the first time, that abscission can positively correlate with non structural carbohydrates levels in the organ that abscise. Bract respiration rate was significantly affected by treatment and postproduction day (PP). Treatments that had higher bract respiration rates (WATER and STS) also had higher levels of non structural carbohydrates in the bracts. Bract respiration rate decreased from day 10 to day 17 PP by approximately 50% (on average of all treatments) and was negatively correlated with bract survival time. In the carbon balance per gram of bract dry weight, the treatments WATER and STS, showed the largest decrease in the content of total carbohydrates and had the highest consumption of carbohydrates through respiration. So, these were the bracts that needed to import a higher amount of carbohydrates per gram of bract dry weight. In the carbon balance for the whole mass of bracts and adjacent stems in an average plant, the treatments WATER and STS continued to allow for the largest decreases in total carbohydrate during postproduction. However, and contradicting the results per gram of bract dry weight, the highest total consumption of carbohydrates by respiration was obtained for the NAA and STS+NAA treatments. It makes sense that bracts that last longer have lower individual carbon consumption while, at the plant level, the increased number of remaining bracts causes a higher overall expenditure. Respiration rate has been used as an indicator of flower longevity, this correlation is here extended for the flower+bract system. Plants that had higher bract respiration rates, most probably, had a higher flow of carbohydrates through the bracts (and flowers), which, in the end, was sensed as a higher carbohydrate level.