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941.
942.
This article focuses on unintended consequences of internal-marketisation strategies on employees’ social belonging to companies. By the example of two case studies, it shows that internal marketisation may foster a fragmentation of social belonging, specifically reflected by established-outsider figurations within the workforce. Moreover, case-study results highlight the importance of “third actors”, e.?g. management, for the fragmentation of social belonging at company level. Therefore, competence building of third actors is required to prevent or effectively deal with fragmentation of social belonging at company level.  相似文献   
943.
Vanishing or decreasing attachment is an indicator for changes within a work-oriented society. This particularly affects employment and our organizational commitment as well as bonds that are established in the context of professional relationships. This text provides a comparative analysis of two attachment-theoretical approaches that have developed simultaneously but independently from one another: commitment research into organizational psychology on the one hand and attachment theory based on developmental psychology on the other. Both are to be examined for their potential, their theoretical and empirical response to current dynamics in the world of work.  相似文献   
944.
The importance of commitment from the point of view of companies or organizations is discussed controversially in recent years. On the one hand, a key competitive advantage is seen in the field of human resources. At the same time, very different forms of employment flexibilization can be observed. These different approaches are shown in this article and the versatile embedding of work such as the perception of disposition possibilities in terms of time, individual room for maneuver or even the experienced social justice. All of these dimensions have the potential to portray themselves as faultlines in organizations and thus have an impact on the binding in organizations.  相似文献   
945.

Background

Since age-related muscle strength loss cannot be explained solely by muscle atrophy, other determinants would also contribute to muscle strength in elderly. The present study aimed to clarify contribution of neuromuscular activation pattern to muscle strength in elderly group. From 88 elderlies (age: 61~?83 years), multi-channel surface electromyography (EMG) of the vastus lateralis muscle was recorded with two-dimensional 64 electrodes during isometric submaximal ramp-up knee extension to assess neuromuscular activation pattern. Correlation analysis and stepwise regression analysis were performed between muscle strength and the parameters for signal amplitude and spatial distribution pattern, i.e., root mean square (RMS), correlation coefficient, and modified entropy of multi-channel surface EMG.

Results

There was a significant correlation between muscle strength and RMS (r =?0.361, p =?0.001) in the elderly. Muscle thickness (r =?0.519, p <?0.001), RMS (r =?0.288, p?=?0.001), and normalized RMS (r =?0.177, p =?0.047) were selected as major determinants of muscle strength in stepwise regression analysis (r?=?0.664 in the selected model).

Conclusion

These results suggest that inter-individual difference in muscle strength in elderly can be partly explained by surface EMG amplitude. We concluded that neuromuscular activation pattern is also major determinants of muscle strength on elderly in addition to indicator of muscle volume.
  相似文献   
946.

Background

The increasing prevalence of obesity in sub-Saharan African women is not well understood, and black South African women in the region are particularly vulnerable. This study aimed to examine whether the relationship of socioeconomic status (SES) with changes in body mass index (BMI) and waist circumference (WC) is mediated by physical activity in ageing African women.

Methods

In a longitudinal analysis of the 518 caregivers associated with the Birth to Twenty Plus study, the role of SES associated with 10-year changes in BMI and WC was tested using structural equation modelling (SEM). The degree of mediation of moderate-vigorous physical activity (MVPA) and sitting time in this association was also assessed.

Results

The prevalence of obesity increased significantly from baseline to follow-up (p?<?0.0001). In the SEM models, baseline SES had a direct positive effect on changes in BMI (β, 95% CI, 0.02 (0.005 to 0.04), and a direct negative effect on changes in MVPA (β, 95% CI, ??3.81 (??6.92 to ??0.70). Baseline MVPA had a direct negative effect (β, 95% CI, ??0.002 (??0.003 to ??0.0003) and indirect positive effect via change in MVPA (β, 95% CI, 0.01 (0.0001 to 0.001) on change in WC.

Conclusions

Our study demonstrates the role and interaction of sociodemographic and behavioural predictors of obesity, and suggests a multifaceted approach to management of the crisis in communities of ageing urban African women.
  相似文献   
947.

Background

Physical exercise (PE), virtual reality-based exercise (VRE), and brain exercise (BE) can influence physical and cognitive conditions in older persons. However, it is not known which of the three types of exercises provide the best effects on physical and cognitive status, and which exercise is preferred by older persons. This study compared the effects of PE, VRE, and BE on balance, muscle strength, cognition, and fall concern. In addition, exercise effort perception and contentment in older persons was evaluated.

Methods

Eighty-four older persons (n?=?84) were randomly selected for PE, VRE, BE, and control groups. The exercise groups received 8-week training, whereas the control group did not. Balance was assessed by Berg Balance Scale (BBS) and Timed Up and Go test (TUG), muscle strength by 5 Times Sit to Stand (5TSTS) and left and right hand grip strength (HGS), cognition by Montreal Cognitive Assessment (MoCA) and Timed Up and Go test Cognition (TUG-cog), fall concern by Fall Efficacy Scale International (FES-I), exercise effort perception by Borg category ratio scale (Borg CR-10), and exercise contentment by a questionnaire.

Results

After exercise, PE significantly enhanced TUG and 5TSTS to a greater extent than VRE (TUG; p?=?0.004, 5TSTS; p?=?0.027) and BE (TUG; p?=?0,012, 5TSTS; p?<?0.001). VRE significantly improved MoCA (p?<?0.001) and FES-I (p?=?0.036) compared to PE, and 5TSTS (p?<?0.001) and FES-I (p?=?0.011) were improved relative to BE. MoCA was significantly enhanced by BE compared to PE (p?<?0.001) and both MoCA and TUG-cog were improved compared to VRE (p?=?0.04). PE and VRE significantly (p < 0.001) increased Borg CR-10 in all exercise sessions, whereas BE showed a significant improvement (p?< 0.001) in the first 4 sessions. Participants had a significantly greater satisfaction with BE than controls (p?=?0.006), and enjoyed VRE and BE more than PE (p?< 0.001). Subjects in all exercise groups exhibited benefits compared to the control group (p?< 0.001).

Conclusions

PE provided the best results in physical tests, VRE produced measurable improvements in physical and cognition scores, while BE enhanced cognition ability in older persons. Older persons preferred VRE and BE compared to PE. Both exercises are suggested to older persons to improve physical and cognitive conditions.
  相似文献   
948.

Background

Previous physical activity (PA) tracking studies have examined the stability of overall PA and/or PA types, but few have investigated how specific types of sport/exercise track over the life course. The aim of this study was to determine how specific sports/exercises in midlife track and predict future sport/exercise and PA in men transitioning to old age.

Methods

Seven thousand seven hundred thirty-five men (aged 40–59?years) recruited in 1978–80 were followed up after 12, 16 and 20?years. At each wave men self-reported participation in sport/exercise. Frequent sport/exercise participants (>?1/month) reported the types of sport/exercise they engaged in. Men also reported total PA, health status, lifestyle behaviours and socio-demographic characteristics. Stability of each sport/exercise was assessed using kappa statistics and intraclass correlation coefficients. Logistic regression estimated the odds of participating in sport/exercise and being active at 20-year follow up according to specific types of sport/exercise in midlife.

Results

Three thousand three hundred eighty-four men with complete data at all waves were included in analyses. Tracking of specific sports/exercises ranged from fair to substantial, with golf being the most common and most stable. Bowls was the most frequently adopted. Odds of participating in sport/exercise and being active in old age varied according to sport/exercise types in midlife. Golf and bowls in midlife were the strongest predictors of sport/exercise participation in old age. Golf, cricket and running/jogging in midlife were among the strongest predictors of being active in old age. Compared to participating in just one sport/exercise in midlife, sampling multiple sports/exercises was more strongly associated with sport/exercise participation and being active in old age.

Conclusion

The stability of sport/exercise participation from midlife to old age varies by type. Specific sports/exercises in midlife may be more likely to predict future PA than others. However, participating in a range of sports/exercises may be optimal for preserving PA into old age.
  相似文献   
949.
Criticism against quantitative methods has grown in the context of “big-data”, charging an empirical, quantitative agenda with expanding to displace qualitative and theoretical approaches indispensable to the future of sociological research. Underscoring the strong convergences between the historical development of empiricism in the scientific method and the apparent turn to quantitative empiricism in sociology, this article uses content and hierarchical clustering analyses on the textual representations of journal articles from 1950 to 2010 to open dialogue on the epistemological issues of contemporary sociological research. In doing so, I push towards the conceptualization of a social scientific method, inspired by the scientific method from the philosophy of science and borne out of growing constructions of a systematically empirical representation among sociology articles. I articulate how this social scientific method is defined by three dimensions – empiricism, and theoretical and discursive compartmentalization –, and how, contrary to popular expectations, knowledge production consequently becomes independent of choice of research method, bound up instead in social constructions that divide its epistemological occurrence into two levels: (i) the way in which social reality is broken down into data, collected and analyzed, and (ii) the way in which this data is framed and made to recursively influence future sociological knowledge production. In this way, empiricism both mediates and is mediated by knowledge production not through the direct manipulation of method or theory use, but by redefining the ways in which methods are being labeled and knowledge framed, remembered, and interpreted.  相似文献   
950.
The article reexamines the prevailing perception of traditional economics as the science of rational choice among contemporary economists and sociologists, especially rational choice theorists. It proposes that conventional economics is not exclusively the theory of rational choice but also one of irrational choices in the economy. The article aims to contribute toward a fuller understanding and appreciation of classical and neoclassical economics, especially among sociologists, as composite rational choice-irrational choice theory and in that sense a multi- rather than single-paradigm science, thus no different from sociology and other social (and physical) sciences. This may be relevant or interesting to sociologists given that their rational choice colleagues, like economists, extol the “virtues" of conventional and modern economics as a single-paradigm, theoretically unified science around “rational choice” and criticize the “vices” of sociology as plagued by competing paradigms and theoretical disunity. The article supports many economic sociologists’ view or intuition of conventional economics as complex rational-irrational choice theory and multi-paradigm science, and disconfirms rational choice theorists’ interpretation and generalization of it as “rational choice theory” only and single-paradigm unified science.  相似文献   
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