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951.
The noise caused by the movement of users on their chairs in the work environment may indicate structural weaknesses and risk, and still significantly reduce productivity by increasing employees stress level. By understanding the activities to be developed in a work place one may understand what should be necessary to a good development, thereafter a search for improvement of labor activity with the aim of better use of resources in the operation of product use may be done. The analysis of the incremental variation of noise in professional chairs aims to identify its origin and the time the emission of noise starts during the period of use, its development and the major causative agents. Determining the characteristics of the sound of different materials and adjustments mechanisms of the chair can determine how different materials interact with each other. The measurement of these noises in an acoustic isolated room using directional microphones, if recorded and analyzed properly makes it possible to investigate and orientate to suspect elements in order to propose solutions and identify the quality of other similar chairs. Based on the results recommendations can be established for the orientation of users, managers and people responsible for the acquisition of the products, inducing them to review the employment of materials and the choice of the processes of production. These aspects are not covered in the Brazilian ergonomics norms and standards in the use of chairs.  相似文献   
952.
Urbanization is a pervasive and growing threat to amphibian populations globally. Although the number of studies is increasing, many aspects of basic amphibian biology have not been investigated in urban settings. We reviewed 32 urban studies from North America and quantified the number of species studied and their response to urbanization. We examined existing research on breeding habitats, life-history stages, movement patterns, and habitat use relative to urbanization. We found amphibians as a whole respond negatively to urbanization (69 reported responses were negative, 6 were positive and 35 showed no effect). We caution, however, that many North American species still lack or are associated with conflicting information regarding species-specific responses (e.g., 89 potential responses were unknown). Approximately 40% of all anuran and 14% of caudate species in North America were investigated in the literature; however, the most diverse genera (e.g., Plethodon and Eurycea) were the most understudied likely due to their cryptic terrestrial lifestyles and biases in sampling protocols that assess wetland habitats via call surveys. Research on movement and small scale habitat use was deficient. Adult, juvenile, tadpole, and egg mass life-history stages commonly served as direct measures of species presence and abundance; however, such data do not accurately reflect recruitment into subsequent age classes and population persistence. The lack of data on many North American species may be contributing to poor management of urban amphibian populations and their habitats.  相似文献   
953.
This article considers the challenge of extending conventional models of flexibility to hourly jobs that are often structured quite differently than the salaried, professional positions for which flexibility options were originally designed. We argue that the assumptions of job rigidity and overwork motivating existing flexibility options may not be broadly applicable across jobs in the US labor market. We focus specifically on two types of flexibility: (1) working reduced hours and (2) varying work timing. We first review central aspects of the US business and policy contexts that inspire our concerns, and then draw on original analyses from US census data and several examples from our comparative case-study research to explain how conventional flexibility options do not always map well onto hourly jobs, and in certain instances may disadvantage workers by undermining their ability to earn an adequate living. We conclude with a discussion of alternative approaches to implementing flexibility in hourly jobs when hours are scarce and fluctuating rather than long and rigid.  相似文献   
954.
In this article, we attempt to conceptualize the historical development and the governance structure of the transnational organic cotton network from Benin. We aim to discover how the organic cotton production‐consumption network is governed locally and internationally. Existing bodies of literature on international agricultural production networks, in particular the Global Value Chains (GVC) perspective, focus on economic dimensions, but find it difficult to incorporate the sustainability dimension. We favour widening the concept of GVCs beyond economics by acknowledging and including environmental rationalities and the representatives of their interests, not as external elements, but rather as co‐governing or co‐structuring factors (or actors) of sustainable value chains. Our findings reveal that beyond the traditional producer versus buyer dualism, intermediate stakeholders, namely transnational and local environmental NGO networks, are instrumental in the construction, maintenance and transformation of the organic cotton network. It is also apparent that farmers' leaders play an important role in mediating and (re)building trust among organic farmers, though they exert insufficient vertical power in the organic cotton network to control it.  相似文献   
955.
956.
This study of 2,163 adult chronic, non-cancer-pain, long-term opioid therapy patients examines the relationship of depression to functional disability by measuring average pain interference, activity limitation days, and employment status. Those with more depression symptoms compared to those with fewer were more likely to have worse disability on all 3 measures (average pain interference score >5, OR = 5.36, p < .0001; activity limitation days ≥ 30, OR = 4.05, p < .0001; unemployed due to health reasons, OR = 4.06, p < .0001). Depression might play a crucial role in the lives of these patients; identifying and treating depression symptoms in chronic pain patients should be a priority.  相似文献   
957.
This study examined biological sex differences in the development of mild cognitive impairment (MCI) and probable Alzheimer’s disease (AD) development as predicted by changes in the hippocampus or white matter hyperintensities. A secondary data analysis of the National Alzheimer’s Coordinating Center Uniform Data Set was conducted. We selected samples of participants with normal cognition at baseline who progressed to MCI (n = 483) and those who progressed to probable AD (n = 211) to determine if hippocampal volume or white matter hyperintensities (WMH) at baseline predicted progression to probable AD or MCI and whether the rate of progression differed between men and women. The survival analyses indicated that changes in hippocampal volumes affected the progression to probable AD (HR = 0.535, 95% CI [0.300–0.953]) only among women. White men had an increased rate of progression to AD (HR = 4.396, CI [1.012–19.08]; HR = 4.665, 95% CI [1.072–20.29]) compared to men in other race and ethnic groups. Among women, increases in hippocampal volume ratio led to decreased rates of progressing to MCI (HR = 0.386, 95% CI [0.166–0.901]). Increased WMH among men led to faster progression to MCI (HR = 1.048. 95% CI [1.011–1.086]). Women and men who were older at baseline were more likely to progress to MCI. In addition, results from longitudinal analyses showed that women with a higher CDR global score, older age at baseline, or more disinhibition symptoms experienced higher odds of MCI development. Changes in hippocampal volumes affect the progression to or odds of probable AD (and MCI) more so among women than men, while changes in WMH affected the progression to MCI only among men.  相似文献   
958.
Retirement is a complex life transition. Women’s retirement, like their work lives, may be further complicated, for example, by family or financial obligations; they may feel forced to retire or to continue working or feel they have the choice to do so. This study examines the role of voluntary versus involuntary retirement or continued work participation among retirement-age women; specifically, the relationships between choice, work status, and well-being. Compared to women forced to retire, women who chose retirement or continuing to work had higher levels of life satisfaction. Findings highlight the importance of examining retirement within the life course context.  相似文献   
959.
960.
In this paper, we use longitudinal data to investigate how parental death and divorce influence young women’s own experience of divorce in Malawi, a setting where women marry relatively early and unions are fragile. We find that maternal death and parental divorce are positively associated with divorce for young women but, after controlling for socio-demographic and marital characteristics, only the association with maternal death remains statistically significant. Maternal and paternal death are both strongly associated with women’s post-divorce living arrangements, which in turn affects their material well-being. This finding suggests that divorcing at a young age shapes the subsequent life chances of women; although some women return to their parental home and may have the opportunity to reset the transition to adulthood, other women begin their 20s as head of their own household and with considerable material disadvantage.  相似文献   
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