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911.
Global guidelines for physical activity are not being met by most of the world’s youths, adults, and older adults. Family and friends who engage in physical activity across generations derive emotional, social, cognitive, and physical benefits from their interaction. Youths depend on adult assistance to travel long distances, adults are encumbered with obligations to work, and older adults often live more than 200 miles from their extended families. Intergenerational physical activity is difficult because generations are distant and lead busy lifestyles. Remotely played exergames can connect family and friends for intergenerational physical activity. Internet exergaming can help to make physical activity convenient and enjoyable as well as eliminate the effect of distance on playing with family and friends.  相似文献   
912.
913.
Grassroots groups often find that they need to manage issues of diversity along racial/ethnic, class, gender, religious, and/or citizenship lines, among several other axes of difference. There are strong reasons to expect that diversity is a benefit to such groups, especially in terms of coalition breadth and the widely held expectation that internal heterogeneity helps organizations to resolve collective action dilemmas. Nonetheless, a long tradition within sociological research sets out the expectation that group heterogeneity thwarts the formation of collective identities and group solidarity, and therefore limits the potential for effective organizing. With a particular emphasis on groups active in local community‐based organizing since the 1970s, we review studies on a variety of features of group diversity and their effects on mobilizing processes. We find that although researchers remain somewhat divided on these critical issues, the preponderance of evidence suggests that managing diversity poses significant challenges for grassroots organizing efforts. While these challenges may not easily be overcome, we point to a variety of cases in which group differences offered a significant asset to social change efforts.  相似文献   
914.
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   
915.
916.
917.
Non-hormonal approaches to premenstrual syndrome (PMS) treatment such as selective serotonin reuptake inhibitors are by no means effective for all women and frequently we must resort to endocrine therapy. During many of the hormonal approaches, PMS-like symptoms can be introduced or re-introduced during the necessary cyclical or continuous progestogen component of the therapy. This is seen with combined oral contraception, progestogen only contraception, progestogen therapy for heavy menstrual bleeding and endometriosis, sequential hormone replacement therapy and any therapeutic strategy for premenstrual syndrome where it is necessary to provide endometrial protection, including estrogen suppression of ovulation or add-back during gonadotrophin releasing hormone suppression. The link to progestogen is very often missed by health professionals. When the pattern of symptoms mimics the cyclicity of PMS, it is termed progestogen-induced premenstrual disorder. The need to use progestogen to protect the endometrium from the proliferative actions of estrogen can pose insurmountable difficulties in managing premenstrual disorders. In the absence of any really useful evidence, nearly all practice in this area depends on clinician experience. We cannot afford to wait for adequate research evidence to be produced - it never will - and so we must rely on empirical findings, clinical experience, theoretical strategies and common sense.  相似文献   
918.
In some occupations pushing forces are frequent when performed on horizontal ground and are standardized (ISO 2002). In special cases employees are obliged to grow container on slopes and the strains are poorly investigated. The objective of this work is to measure forces required to push garbage container on horizontal and inclined at 0, 4, 11 and 16 % grounds. Sudden and significant increases in heart rate reflect the possible risk of heart overload in long displacements. This study proposes realistic limits and provides a simple and protective tool for a group of employees without distinction of age or gender. These limits can even be reduced to a quasi-linear model where push 200 kg is the maximum for 0% slope and 60 kg for 10% slope.  相似文献   
919.
In order to implement preventive programs to prevent back pain in nurses, assessments of the degree of passivity and mobility of patients is imperative. After all, the load in health care ergonomics, is often the patient. The degree of cooperation or resistance determines the load on the back for the nurses and the necessity of the use of lifting devices like patient lifters or sliding sheets. These assessments must be done in both a practical and a reliable way. For this purpose a 3-category and a 5- category system to assess the degree of patient mobility and passivity was developed and tested. The results are presented on the poster.  相似文献   
920.
In hospitals many horizontal transfers (from stretcher to bed etc.) are performed from the moment a patient is admitted (f.e. with an ambulance) through examination departments all the way to the wards. These transfers can be very strenuous and solutions may be to use a special lifting device that accompanies the patient on this route: a stretcher sling This is a specially designed disposable lifting sling for horizontal transfers and repositioning, the sling can easily be connected to a ceiling or mobile lift. The ambulance service, two hospitals and a manufacturer decided to study the effects. The stretcher sling travels with the patient. Does this provide an ergonomically sound solution and is this an effective and efficient solution? The results were positive, but a behavioral change was also necessary.  相似文献   
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