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851.
Recent research has revealed the important role of multimodal object exploration in infants' cognitive and social development. Yet, the real‐time effects of postural position on infants' object exploration have been largely ignored. In the current study, 5‐ to 7‐month‐old infants (N = 29) handled objects while placed in supported sitting, supine, and prone postures, and their spontaneous exploratory behaviors were observed. Infants produced more manual, oral, and visual exploration in sitting compared to lying supine and prone. Moreover, while sitting, infants more often coupled manual exploration with mouthing and visual examination. Infants' opportunities for learning from object exploration are embedded within a real‐time postural context that constrains the quantity and quality of exploratory behavior. 相似文献
852.
This study was designed to explore the grandparent-grandchild relationship from the perspective of South African adolescents, and to investigate whether grandparental involvement is independently associated with adolescents’ psychological well-being. Data were collected from 204 adolescents (mean age = 13.69) using a school-based survey. Results revealed high levels of contact between grandparents and grandchildren, although involvement varied depending on grandparent, grandchild, and family characteristics. Grandparental involvement was significantly associated with more adolescent prosocial behavior, independent of parental involvement. The findings suggest a unique association between grandparental involvement and prosocial behavior that is robust across different cultural contexts. 相似文献
853.
Previous studies find that some social groups are stuck in poverty traps because of network effects. However, these studies do not carefully analyze how these groups overcome low human capital investment activities. Unlike previous studies, the model in this paper includes network externalities in both the human capital investment stage and the subsequent career stages. This implies that not only the current network quality, but also the expectations about future network quality affect the current investment decision. Consequently, the coordinated expectation among the group members can play a crucial role in the determination of the final state. We define “overlap” for some initial skill ranges, whereby the economic performance of a group can be improved simply by increasing expectations of a brighter future. We also define “poverty trap” for some ranges, wherein a disadvantaged group is constrained by its history, and we explore the egalitarian policies to mobilize the group out of the trap. 相似文献
854.
The aim of this paper is to provide new evidence on the effect of partners’ wages on partners’ allocation of time. Earlier studies concluded that wage rates are an important determinant of partners’ hours of market and non-market work and also that house work may lower married women’s wage rates. However, the bulk of earlier literature in this area failed to account for the endogeneity of wages or the simultaneity of partners’ time allocation choices. Here we take a reduced form approach and specify a ten simultaneous equations model of wage rates, employment and hours of market work, house work and childcare of parents. Non-participants are included in the model. We exploit a rich time use dataset for France to estimate the model. We find that the own wage affects positively own market hours and negatively own house work and childcare hours. The wage of the father has a significantly negative effect on the mother’s market hours while her wage rate has a significantly positive effect on his house work hours. 相似文献
855.
E. Gorman H. M. Hanson P. H. Yang K. M. Khan T. Liu-Ambrose M. C. Ashe 《European review of aging and physical activity》2014,11(1):35-49
Accelerometers objectively monitor physical activity and sedentary patterns and are increasingly used in the research setting. It is important to maintain consistency in data analysis and reporting, therefore, we: (1) systematically identified studies using accelerometry (ActiGraph, Pensacola, FL, USA) to measure moderate-to-vigorous physical activity (MVPA) and sedentary time in older adults, and (2) based on the review findings, we used different cut-points obtained to analyze accelerometry data from a sample of community-dwelling older women. We identified 59 articles with cut-points ranging between 574 and 3,250 counts/min for MVPA and 50 and 500 counts/min for sedentary time. Using these cut-points and data from women (mean age, 70 years), the median MVPA minutes per day ranged between 4 and 80 min while percentage of sedentary time per day ranged between 62 % and 86 %. These data highlight (1) the importance of reporting detailed information on the analysis assumptions and (2) that results can differ greatly depending on analysis parameters. 相似文献
856.
Concerns about decreasing response rates have led to many nonresponse studies. Unfortunately, usually only a limited amount of data is available on nonrespondents. Linking administrative data makes information available on all the sampled units including nonrespondents. Statistics Netherlands has constructed a database in which several administrative records and several surveys are connected. In this explorative study we use this dataset to look for homogenous groups of respondents and nonrespondents in survey research using latent class cluster analysis. Latent class techniques can provide insight into the problem of selective nonresponse and currently under-represented societal groups. We identify four different latent classes in a recent Dutch survey and replicate the findings for the same survey conducted 4 years later. Two of the types of sampled units have above-average response rates and the other two have below-average response rates. We also evaluate various latent class models with other response outcomes to gain insight into the contact and cooperation process. 相似文献
857.
Universities, particularly research‐intensive ones, have responded to a variety of external and internal influences by retooling their missions, culture, and organizational structures to generate revenue from market opportunities. This has resulted in the marketization of higher education: organizational practices that blur the boundary between knowledge‐driven and profit‐driven institutions. This blurring has spurred debates and uncertainties over the scope and boundaries of the 21st century university. We argue that these debates spring from institutional boundary work at the intersection of the three main missions of the contemporary academy: knowledge production, student learning, and satisfying the social charter. These missions can sometimes create areas of synergy, but also tensions that are particularly acute where market logics and business‐oriented practices contradict academic values. Within knowledge production, a key dilemma is the extent to which knowledge advancement should aim for transcendence versus revenue generation. Within student learning, the dilemma involves incommensurability between the ideals of democratic citizenship and demonstrable return on investment. Within the social charter mission, the dilemma is over whether the university can serve the public welfare while also facilitating the growth of local and national economies. 相似文献
858.
Packaging and labeling play a crucial role awhile protecting medicaments and transmitting a range of crucial information to the users. Taking into account the scarcity of specific studies in this area, it was considered great the need for a comprehensive survey about customers' satisfaction when handling these containers. 相似文献
859.
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
860.
This poster intends to show how measurement, its concepts and methods are decisive to the ergonomic praxis and why their agents should be aware of how incertainty can be taken in the process in order to increase the accuracy of measurement and findings. 相似文献