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41.
The aim of this study was to analyze differences in biomechanical parameters between elderly and control participants when stepping up, to evaluate control of balance. Eleven control and 14 elderly participants performed a step from an initial static posture onto a 7-cm-high force plate. For the spontaneous-velocity condition, elderly participants performed a slower progression velocity than control participants. Elderly participants spent proportionally more time in stance phase, with a corresponding decrease in swing phase, than the control participants, irrespective of movement velocity. In contrast, at spontaneous velocity the parameters related to ground-reaction force (GRF) showed that anteroposterior and mediolateral forces at toe-off of the support limb and the slope of vertical force during weight transfer were significantly smaller for the elderly than for control participants. These GRF parameters depended on the stepping-up velocity. The elderly develop a spatiotemporal strategy and reduced movement velocity to control support balance.  相似文献   
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Until the end of the 1990s, mortality patterns and trends in Estonia, Latvia and Lithuania were remarkably similar. However, from the year 2000 onwards, life expectancy trends in the three countries started to diverge. In particular, sustainable progress in Estonia over the period 2000–2007 contrasts with stagnation in Latvia, and even worsening trends in Lithuania. These contradictory changes seem to be mainly explained by contrasting dynamics in mortality from cardiovascular diseases, external causes of death and digestive system diseases. Whereas cardiovascular and external-cause mortality declined in Estonia and Latvia, worsening or stagnation of mortality from these causes of death was observed in Lithuania. The negative mortality changes in Lithuania were also reinforced by a striking increase in mortality from alcohol-related digestive system diseases. The findings suggest that the divergence in health trends between the three countries may be attributable to their varying degrees of success in implementing structural health care reforms and specific health policy measures. By contrast, the very recent improvement (since 2008) is parallel in the three countries and is largely because of the introduction of rather similar anti-alcohol measures.  相似文献   
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Urban Ecosystems - Urban green recreational spaces may provide habitat for animals and plants. We investigated the importance of urban public parks in the city of Rio de Janeiro with regard to the...  相似文献   
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A new measure is developed for the distance between relative price vectors. It is shown to be related to Gini’s Index of Concentration and is applied to cross-country data for the year 1975.  相似文献   
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Users of multistate life tables and projections have recognized that the Markovian assumptions underlying such models are unduly restrictive and should be relaxed whenever data permit. Efforts to include the influences of previous occupancies have included the incorporation of place‐of‐birth dependence. This paper addresses the stable growth properties of such generalized multistate models. It shows how place‐of‐birth‐specific stable growth measures can be calculated without projection simply by solving the characteristic equation. An example using Canadian data illustrates the argument.  相似文献   
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Review of Economics of the Household - We apply diversity indices, such as the Gini-Simpson index and entropy related indices, to the study of the distribution of individual asset holdings in the...  相似文献   
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