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61.
This paper examines two ‘ends’ of identity online – birth and death – through the analytical lens of specific hashtags on the Instagram platform. These ends are examined in tandem in an attempt to surface commonalities in the way that individuals use visual social media when sharing information about other people. A range of emerging norms in digital discourses about birth and death are uncovered, and it is significant that in both cases the individuals being talked about cannot reply for themselves. Issues of agency in representation therefore frame the analysis. After sorting through a number of entry points, images and videos with the #ultrasound and #funeral hashtags were tracked for three months in 2014. Ultrasound images and videos on Instagram revealed a range of communication and representation strategies, most highlighting social experiences and emotional peaks. There are, however, also significant privacy issues as a significant proportion of public accounts share personally identifiable metadata about the mother and unborn child, although these issue are not apparent in relation to funeral images. Unlike other social media platforms, grief on Instagram is found to be more about personal expressions of loss rather than affording spaces of collective commemoration. A range of related practices and themes, such as commerce and humour, were also documented as a part of the spectrum of activity on the Instagram platform. Norms specific to each collection emerged from this analysis, which are then compared to document research about other social media platforms, especially Facebook.  相似文献   
62.

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   
63.
It is well known that in finance variances and covariances of asset returns move together over time. Recently, much interest has been aroused by an approach involving the use of the realized covariance (RCOV) matrix constructed from high-frequency returns as the ex-post realization of the covariance matrix of low-frequency returns. For the analysis of dynamics of RCOV matrices, we propose the generalized conditional autoregressive Wishart (GCAW) model. Both the noncentrality matrix and scale matrix of the Wishart distribution are driven by the lagged values of RCOV matrices, and represent two different sources of dynamics, respectively. The GCAW is a generalization of the existing models, and accounts for symmetry and positive definiteness of RCOV matrices without imposing any parametric restriction. Some important properties such as conditional moments, unconditional moments, and stationarity are discussed. Empirical examples including sequences of daily RCOV matrices from the New York Stock Exchange illustrate that our model outperforms the existing models in terms of model fitting and forecasting.  相似文献   
64.
Guided by Cantor’s social care model, this study identified individual, family, and social support factors that influence urban older adults’ need for home- and community-based services, including medical and rehabilitation, instrumental care and support, and psychosocial services. The data were extracted from the Sample Survey on Aged Population in Urban/Rural China conducted by the China Research Center on Aging in 2006. Results from multiple logistic regression show that older adults’ need for medical and rehabilitation services is significantly related to instrumental activities of daily living, depression, not having filial children, friend support networks, and having a confidant. Older adults’ need for instrumental care and support is related to their educational attainment, financial strain, instrumental activities of daily living, not living with children, and friend support networks. Finally, older adults’ need for psychosocial services is significantly related to educational attainment, depression, not being married, friend support networks, and having a confidant. Implications for social service development are discussed.  相似文献   
65.
In 2012, the Australian Government announced the establishment of a Royal Commission into Institutional Responses to Child Sexual Abuse. The aim of the Royal Commission is to understand how and why sexual abuse occurred within Australian institutions and to provide guidance as to how future abuse might be prevented. The Royal Commission commissioned a mixed methods study to explore what children need to be safe and to feel safe, to explore how they determine their level of safety, and their observations about how institutions act to prevent and respond to safety issues. This article reports on the findings from the first phase of the study that involved focus groups carried out with children aged 4–17 years from different types of institutions. The discussion focused particularly on how children conceptualise safety and how they make judgments about their levels of safety. Children and young people's conceptualisation of safety had multiple dimensions, which include the idea that being safe and feeling safe are two distinct, interrelated but sometimes non‐concurrent experiences; that safety is identified and experienced as a set of feelings; trusting relationships are the foundation of safety; familiarity helps children feel safe; and safe environments are those that are ordered and orderly.  相似文献   
66.
Family support policies (FSP) refer to government policies that promote the well-being of families with children (e.g. job-protected paid leave, cash transfers, childcare). We developed an initial conceptual and theoretical framework of FSP and conducted a realist-scoping review to document the state of evidence regarding the influence of FSP on three child outcomes: poverty, development, and health. Based on the contexts and mechanisms through which FSP are hypothesized to affect child outcomes, we constructed a framework to guide a search of five electronic databases (OVID, ProQuest, PubMed, Scopus, and Web of Knowledge). We analysed articles meeting our inclusion criteria (i.e. conceptualized FSP as a function of the welfare state; conceptualized child poverty, development, and health as outcomes; and conducted empirical analyses) in relation to our mechanisms and thematic concerns (context, developmental periods, and differential impacts). A total of 22 studies met our inclusion criteria, which tested 25 independent child outcomes. Our findings identified initial mechanisms that explain the relationship between FSP and child outcomes through (1) increasing parents’ basic capabilities, (2) shaping parents’ childcare options, and (3) influencing parental leave-taking and shifting beliefs about gender relationships in the home and workplace. Future work will be to test these mechanisms and framework through a realist synthesis.  相似文献   
67.
This study explored whether and how family relationships and social connections influence depressive symptoms of older migrants and older adults in transnational families using the data gathered from a cross-sectional survey in Los Angeles, California, United States, and Beijing, China. Regression results showed that the older migrants reported significantly higher levels of depression than the elders in transnational families. The findings highlight the importance of maintaining close family relations and having large friendship networks for older adults in international migrant families.  相似文献   
68.
Transportation infrastructures play an essential role in influencing population and employment change. While railroads, highways, and airports were constructed in different time periods, now they complement each other in terms of providing accessibility. This study uses county-level data to examine the impacts of the three forms of transportation infrastructure on population and employment change in the continental United States from 1970 to 2010. The findings suggest that transportation infrastructures play evolving but complementary roles in affecting population and employment change during the study period: railroads act as a distributive factor, highways take a facilitator role, and airports behave like growth poles. Diversification of the roles indicates that transportation infrastructures have evolved from a pure growth factor to an essential multifaceted development element of human society.  相似文献   
69.
70.
Why similar people have different patterns of wealth accumulation is puzzling. The behavioral life-cycle hypothesis indicates self-control is an important aspect of household saving behavior. This study investigated if household wealth creation from 1994 to 2008 could be predicted by self-control among a sample of young baby boomers using National Longitudinal Survey of Youth (NLSY79) data. Variables that significantly predicted 2008 net worth included homeownership, 1994 net worth, income, bankruptcy filing, inheritance, education level, race, marital status, children, retirement planning activities, locus of control, and self-mastery. The addition of self-control predictors to a regression model improved the model’s ability to predict net worth by 1.3 % above and beyond the human capital, financial status, and demographic predictor variables. In total, the model explained 60 % of the variance in net worth. Findings indicated that individuals who invested in their human capital, were homeowners, and had higher self-control, accumulated more wealth.  相似文献   
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