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671.
Much research shows that breastfeeding provides short- and long-term health benefits for both mothers and their children. However, few studies have yet investigated the factors which may promote or inhibit breastfeeding practices in Japan. To fill this research gap, this paper uses data newly gathered in 2012 on breastfeeding initiation and duration for each child of each mother, which enable us to estimate mother fixed-effects models that control for unobserved differences among mothers. Compared to mothers who leave their jobs after childbirth, mothers who return to work within a year after childbirth do not significantly differ in breastfeeding initiation but have a breastfeeding duration which is shorter by 1.654 months. On the other hand, when fathers work under a flextime system after childbirth, breastfeeding initiation is higher, and the duration is longer by 4.418 months. Therefore, letting fathers work under a flextime system would help promote breastfeeding practices in Japan.  相似文献   
672.
We investigate whether the adoption of joint-custody laws affects the amount of time that married mothers and fathers devote to market and household work. Our findings suggest that custody reform induces a reallocation of time within marriage, with mothers working more in the market and fathers working more in the home. However, fathers lower their labor-force-participation rates in response to custody reform. The patterns in the data are most easily reconciled with models that emphasize shifts in bargaining power to one household member, which is likely the father in the case of joint-custody reform.  相似文献   
673.
The Spanish Roma population have co-existed with the broader population of Spain, under the same laws and regulations for more than 500 years, but they exhibit very different fertility patterns. The aim of this paper is to determine whether there are factors other than income or education that can explain the larger number of children in Spanish Roma families. Our analysis reveals that the existence of a family business, which is highly labor-demanding, appears to be associated with parental decisions concerning the number of children. Since parental authority, in Roma families, holds sway over children even after their own marriage, the future labor contributions of children are particularly beneficial to the family business.  相似文献   
674.
This article of the magazine Gruppe, Interaktion, Organisation (GIO) covers the role of talent management regarding the digitisation of enterprises. Talent Management contributes to this process by identifying, developing and placing talent for the digitisation of enterprises. Deutsche Bahn utilizes a variety of approaches to digitize talent management.  相似文献   
675.
676.

Background

Centenarians are a growing population in Europe and present significant variability in motor and cognitive functions. The aim of our study was to characterize health status, as well as cognitive and motor functions in a group of Portuguese centenarians. In addition, our study also aimed at analyzing the relationship between cognitive functions and the burden of diseases affecting the elderly.

Methods

Fifty-two centenarians were evaluated using the Mini-Mental State Examination, short version. Walking-related parameters (velocity and time spent in the 3 m walk test), grip strength and number of age-related illnesses were also measured. The relationship between cognitive scores and time spent in the three metre walk test, velocity, grip strength and number of diseases was analysed.

Results

Cognitive scores showed a positive correlation with both handgrip strength and time spent in the three metre walk. In contrast, no association was found between cognitive scores and the presence/absence of disease, walking velocity or number of diseases present.

Conclusions

These results suggest that in centenarians, cognitive functions may be related with motor functions.
  相似文献   
677.

Background

A low urine pH is a characteristic metabolic feature of metabolic syndrome and type 2 diabetes. The purpose of the current study was to investigate the effects of a 12-week home-based bench step exercise on the urine pH status of elderly female subjects.

Methods

The current study is a secondary analysis of a randomized controlled trial (RCT) in which 59 postmenopausal female subjects were randomized to either the exercise group (n?=?29) or the control group (n?=?30). The subjects in the exercise group were instructed to perform home-based exercises using a bench step at the anaerobic threshold (AT), with a goal of performing ≥140 min/week at home for 12 weeks. The subjects in the control group were instructed to not change their normal lifestyle. Urine was collected after overnight fasting, and the urine pH was measured using a urinary test strip. The inter-group-differences at baseline and the pre-post changes within groups were assessed using the Mann-Whitney U test and Wilcoxon’s signed-rank test, respectively. Additionally, the difference in the post-intervention urine pH levels of the two groups, adjusted for the pre-intervention values (the estimated effect size) and the precision (95% confidence intervals) were investigated using an analysis of covariance.

Results

The pre-post comparison of the urine pH data using Wilcoxon’s signed-rank test showed a significant increase in the urine pH levels of the exercise group (p?<?0.05); there was no significant change in the urine pH levels of the control group. However, the estimated effect size (0.15) was small and the confidence interval straddled 0 (?0.25–0.55).

Conclusions

Based on the results of the current secondary analysis of an RCT, we could not clearly conclude that exercise has a beneficial effect on the urine pH. Further well-designed RCTs should be conducted to determine whether aerobic exercise is truly able to ameliorate urine acidification.

Trial registration

The study was retrospectively registered in the University Hospital Medical Information Network (UMIN) as “Effect of step exercise on aerobic fitness and progression of atherosclerosis in the elderly” under the registration number UMIN 000026743 (the date of registration: March 28, 2017).
  相似文献   
678.
Research has examined various elements of Twitter; however, no scholarship has explored how sociologists currently use the platform. This empirically driven paper explores how individuals that self-identify as sociologists on Twitter use the popular micro-blogging social media site. A total of 152,977 tweets from Twitter profiles of 130 sociologists were collected and examined using qualitative media analysis. The potential use of Twitter allows the sociologist to become both the generator and interlocutor of dialogue with publics. We frame our data analysis and discussion around the core theme of expertise - namely, the role that expertise plays in the use of Twitter by sociologists. Our findings indicate that when sociologists used Twitter as sociologists (i.e., drawing upon their stated research expertise) little direct engagement with publics occurred. Thus, while sociologists appear to be using Twitter as a space for public sociology, the use of this interactive platform is mostly limited to the generation of content, a finding consistent with Burawoy’s traditional form of public sociology. Suggestions for future research are noted.  相似文献   
679.
In response to the system for regulating research with human subjects, researchers have raised two apparently contradictory concerns: that IRBs are excessively inconsistent (often raised by biomedical researchers), and that they are excessively standardizing (often raised by qualitative interview researchers). Why does standardization appear as the dominant theme in qualitative researchers’ experiences with their IRBs? And how do qualitative researchers experience standardization in their IRB encounters? We focus on IRBs role as regulatory bureaucracies, which typically rely heavily on standardized communication and decisions to process information and make large numbers of decisions in a timely manner. We explore the role of standardization in IRB regulation of qualitative research in an analysis of semi-structured interviews with 26 qualitative sociologists from six research universities and three liberal arts colleges in the Northeastern United States. In a regulatory regime oriented toward the norms of experimental research, these frictions resulted partly from a lack of appropriate standardized language and decision-templates, but also from the inherent difficulties of applying standardized decisions to work that is unpredictable, unique, and difficult to routinize.  相似文献   
680.
While cognitive sociology is a relatively new area in U.S. sociology, the subfield has a lengthy history in French sociology. Developing a typology based upon the existing literature, we identify three branches of cognitive sociology in France. The first was initiated by Raymond Boudon, one of the scholars most responsible for popularizing the area, who envisioned cognitive sociology as helping delineate the role of beliefs in rational action. Second, another group of researchers seeks to found sociology upon a naturalistic basis, thus drawing upon the disciplines constitutive of cognitive science (e.g., psychology, cognitive neuroscience, and cognitive anthropology). Finally, the third approach to cognitive sociology in France takes inspiration from linguistics as a foundation for sociological investigations. We conclude the paper by discussing the relationship between these three sub-fields and by examining the relationship between French and American cognitive sociologies in order to identify fruitful directions for future research.  相似文献   
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