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排序方式: 共有7554条查询结果,搜索用时 15 毫秒
311.
The rate of population aging is increasing in the developing world and the trend is particularly dramatic in East Asia. One consequence is sharp increases in old-age dependency ratios which have major implications for the sustainability of current public pension schemes. These trends are pushing pension policy experts in many of these countries to search for new pension models that are more suited to the increased demographic pressures they will be facing in the decades ahead. In this article we discuss five alternative public pension models with a focus on the newest of these models, the notional defined contribution (NDC) approach. We consider three countries with very different pension systems in place, two from East Asia (China and South Korea) and one from South East Asia (Singapore). The central question we address is which (if any) of the limitations in these existing models might more adequately be addressed using a variant of the NDC model. We conclude that the NDC model has the most to offer China and the least to offer Singapore.  相似文献   
312.
Many community-residing older adults in the United States report past year mistreatment; however, little is known about mental health correlates of abuse. This study investigated whether a recent history of emotional, physical, or sexual abuse is associated with self-reported emotional symptoms (e.g., anxiety, depression) among a representative sample of older adults. Results demonstrated that each abuse type increased likelihood of reporting emotional symptoms; when other known correlates were controlled, only emotional abuse remained a significant predictor. Additional study of mistreatment-related correlates of depression and anxiety is needed, with a focus on the often overlooked category of emotional mistreatment.  相似文献   
313.
314.
We study postpartum decisions about paid work and breastfeeding using a simultaneous equations model. For our sample of higher socioeconomic status mothers, we find a joint decision process for three sets of decisions modeled: work leave duration and duration of any, as well as of exclusive, breastfeeding, and daily work hours and daily breastfeedings at infant age 3 months. We find that returning to paid work 1 week earlier reduces any breastfeeding duration by about two-thirds of a week while extending breastfeeding by a week delays work participation by about one-third of a week. We find larger elasticities for decisions involving daily work hours and number of breastfeedings at 3 months than for work leave duration and any breastfeeding duration and the smallest elasticities for duration of exclusive breastfeeding and work leave. This marks the first study to find a joint decision-making process for postpartum work and breastfeeding decisions and suggests that, in addition to increased leave impacting breastfeeding behaviors, successful breastfeeding promotion policies can have nontrivial impacts on the US labor market.  相似文献   
315.
This study aimed to perform an ergonomic analysis in a fiberglass parts factory. For this purpose, was used the methodology of Ergonomic Work Analysis (EWA). At the end of the study it was possible to identify some ways to the development of improvements in order to contribute to the transformation of working conditions in the sector analyzed.  相似文献   
316.
The operating microscopes may be a significant cause of fatigue and discomfort in surgeons. The need for the microscope to be placed over the operating field forces surgeons to remain at the microscope's eyepieces at an uncomfortable posture for the entirety of the surgery. This study compared the effects on microsurgical task performance for four visualization methods: a monocular microscope, a binocular microscope, a three-dimensional (3D) flat-panel television display and a two-dimensional (2D) flat-panel television display. Eleven subjects each performed two microsurgical tasks and their performance was documented by video camera. The statistical analysis performed indicated utilization of the microscope as a visualization method increased subject performance. No significant difference in performance between the 2D and stereoscopic visualization methods.  相似文献   
317.
The problems related to the means of transport in urban Brazilians have been getting worse over the years. The increase of the fleet, to the detriment of the adequacy and extent of the road network of cities contributes to this fact. This paper presents a profile of users of cycling in the city of Juiz de Fora, and thus contributes to the study of sustainable urban mobility, providing researchers with information that can guide the search for the encouragement of the use of means of transport to meet environmental needs urban centers that contributes to social equity.  相似文献   
318.
The aim is to identify ergonomic intervention methods used for including people with disabilities (PD) in the Brazilian labor market, with emphasis on discussion of methods to analyze the fit between the worker and the workplace. Methods to evaluate the fit of the worker to the workplace identify the capabilities and limitations of PDs and the demands of work, combining these data, and comparing them, in order to obtain a detailed analysis of the fit were drawn from national and international publications. These show that the use of specific methods for PDs and others focused on the general population. Mutatis mutandis, there is a need for complementary tools to address this segment. Thus, for the Brazilian scenario, it is essential to develop specific methodological tools to assess the capabilities of a PD so that they may better interact with their job.  相似文献   
319.
The number of occupational diseases in Mexico is alarming and clearly it is important to do studies with the purpose of improving the design of workstations. The objective of this research is to determine the maximum force levels in different positions of shoulder and elbow. An experiment was conducted with 16 subjects between 18 and 28 years old: 8 male and 8 female. We considered 16 different positions, working with the right and left arm to perform the tasks of pull and push. The tasks consisted of pushing or pulling a dynamometer for a period of 3 seconds as hard as possible. The results were presented in tables. The tables show the mean, standard deviation and range of force levels in different positions.  相似文献   
320.
This study examined the bidirectional relations between authoritative parenting and adolescents’ prosocial behavior over a 1‐year time period. Data were taken from Time 2 and 3 of the Flourishing Families Project, and included reports from 319 two‐parent families with an adolescent child (M age of child at Time 2 = 12.34, SD = 1.06, 52% girls). Cross‐lag analyses supported bidirectional relations between parenting and prosocial behavior with particular emphasis on the role of the adolescents’ prosocial behavior on subsequent parenting. Results also varied as a function of the reporter. Discussion focuses on the implications for understanding the multifaceted nature of prosocial development in adolescence.  相似文献   
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