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51.
There is general consensus that physical activity is important for preserving functional capacities of older adults and positively influencing quality of life. While accelerometry is widely accepted and applied to assess physical activity in studies, several problems with this method remain (e.g., low retest reliability, measurement errors). The aim of this study was to test the intra-instrumental retest reliability of a wrist-worn accelerometer in a 3-day measurement of physical activity in older adults and to compare different estimators. A sample of 123 older adults (76.5?±?5.1?years, 59?% female) wore a uniaxial accelerometer continuously for 1?week. The data were split into two repeated measurement values (week set) of 3?days each. The sum, the 80?C99th quantiles and the 80?C99th trimmed sums were built for each week set. Retest reliability was assessed for each estimator and graphically demonstrated by Bland?CAltman plots. The intraclass correlation of the retest reliability ranged from 0.22 to 0.91. Retest reliability increases when a more robust estimator than the overall sum is used. Therefore, the trimmed sum can be recommended as a conservative estimate of the physical activity level of older adults.  相似文献   
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Previous research shows that work ability of nurses decreases with age. In our study we therefore addressed the following questions: Do successful ageing strategies at work in terms of selection, optimization, and compensation (SOC) support the work ability of nurses? Does SOC mediate the relationship between job control (i.e., decision opportunities at work) and work ability? Does the mediation differ between age-groups? 438 nurses (Age Range 21-63 years) completed a questionnaire in the course of an employee survey. Results show that SOC is positively related with work ability. The positive effect of job control on work ability is significantly mediated by SOC. There are stronger mediating effects for elder nurses than for younger nurses. Results indicate that the interplay of job control and SOC at work helps to maintain the work ability of nurses in nursing care.  相似文献   
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The raccoon is often considered a synanthropic species; however, most urban research on this species has been restricted to urban parks or green spaces. Little is known about the persistence of synanthropic characteristics in the raccoon within the urban matrix. We examined density, den selection, home range size, habitat selection, and survival for adult raccoons (Procyon lotor) during summer (June?CAugust) and autumn (September?CNovember) in two residential neighborhoods, Linthicum located inland, and Riviera Beach on a peninsula in the Potomac river, in Southern Maryland. Den site selection varied by gender (P?=?0.0002) and study site (P?=?0.052), and study site interacted with gender (P?=?0.0063), with female raccoons denning preferentially on the ground and male raccoons in human structures in Riviera Beach while in Linthicum females denned preferentially in trees and males avoided human structures. Seasonal home range size was larger for males (P?<?0.0001) than females at both sites. Habitat selection varied at different hierarchical levels, and between gender, season and site. Intersite differences in habitat selection were apparent at the second order and third order scale. Aquatic and urban habitat was ranked high and woodland consistently lowest in second order scale at Riviera Beach while urban habitat was consistently ranked lowest at Linthicum where woodland ranked highest. Between the hierarchal scales (2nd and 3rd order) a difference in habitat selection occurred at Linthicum only where urban habitats ranked lowest at 3rd order. The differences in patterns of habitat selection we observed between two urban sites at different hierarchical scales suggest that resource selection is dependent upon the specific characteristics of the site and that raccoons exhibit variable responses to changes in landscape features. Finally, male survival tended to be lower (P?=?0.079) than female survival in both study sites. Our results reveal that raccoons can continue to exhibit synanthropic characteristics within the urban matrix even in areas with little natural habitat. This ability to adjust to different levels of development allows the raccoon to occur throughout most parts of the urban landscape, which has important management implications for human-raccoon conflicts and disease management.  相似文献   
56.
The main objectives of social assistance benefits, including poverty alleviation and labor-market or social reintegration, can be seriously compromised if support is difficult to access. While recent studies point to high non-take-up rates, existing evidence does not make full use of the information recorded by benefit agencies. Most studies have to rely on interview-based data, with misreporting and measurement errors affecting the variables needed to establish both benefit receipt and benefit entitlement. In this paper, we exploit a unique combination of Finnish administrative data and eligibility simulations based on the tax-benefit calculator of the Finnish authorities, carefully investigating the measurement issues that remain. We find rates of non-take-up that are both substantial and robust: 40 to 50% of those eligible do not claim. Using repeated cross-section estimations for years 1996?C2003, we identify a set of stable determinants of claiming behavior and suggest that changes in behavior could drive the observed downward trend in take-up rates during the post-recession period. We discuss the poverty implications of our results.  相似文献   
57.
Intergenerational transmission has been successfully employed in economic research to explain the persistence of certain economic behaviors across generations. This paper evaluates the relevance of this transmission process in the formation of gender roles during childhood. In particular, we analyze the relationship between parents?? and children??s housework allocation patterns. We propose a simple theoretical model that predicts that parents with a strong adherence to gender to traditional gender norms??as proxied by their division of household labor??are more likely to allocate housework to children in a way that reflects stereotypes of men??s and women??s domestic tasks. The empirical application is carried out with data from the 2002?C2003 Spanish Time Use Survey. The sample restricts to two-parent households with at least one child aged 10?C17?years. We find a significant positive correlation between a more egalitarian parents?? allocation of housework and a less asymmetrical distribution of domestic chores between sons and daughters.  相似文献   
58.
The study shows that a structural conflict of interest in non-executive boards exists due to missing corporate governance structures and a lack of awareness for legal issues with regard to information security risks. Non-executive boards receive information on strategic security threats as a part of their oversight function to fulfill investor interest in transparency. At the same time, they act as representatives of company stakeholders and have an interest to counteract to information security risks based on the stakeholder’s risk disposition. If not properly structured by corporate governance rules, these different interests may lead to regulatory aberrations on non-executive board level. The study analyses a Deutsche Telekom AG case where non-executive board members, employees, and journalists fell victim to a spying scandal subject to the German telecommunications secrecy law in 2005–2006. The analysis demonstrates how the handling of information security on non-executive board level bears governance risks as well as legal risks that are insufficiently addressed in corporate governance research. The paper contributes to avoid a reproduction of events in the future, by suggesting the principle of a segregation of duties on non-executive boards as well as providing an overview of relevant legislative requirements that clarify tasks of non-executive board members with regard to information security. The study therefore helps protecting corporations and their stakeholders from similar consequences of missing corporate security governance.  相似文献   
59.
This paper adds to the literature on the determinants of the effects of private equity (PE) investments. Using an original dataset of 191 target firms in Italy, we study the effects on performance and governance of the stakes acquired by the PE investor. We employ a difference-in-differences approach and compare target and control firms sharing similar characteristics and performance in the years preceding the deal. We find that PE investment has a positive effect on profitability, sales, and employment; these effects are larger for minority investments. We argue that this signals effective governance that follows from complementing rather than substituting incumbent managers in minority investments.  相似文献   
60.
This study aims to identify whether a relationship exists between the controlling shareholders’ voting power and outside directors’ effectiveness in maximizing firms’ financial performance. We analyze a panel data with 3057 observations for the 2000–2012 period using a random effects model, logit and probit regressions, and the two-stage model of Heckman in the Brazilian stock market. Our findings show that firms whose controlling shareholders use dual class shares to leverage their voting power have less independence from the board and worse financial performance and market value. Further, the percentage of outside directors tends to be ineffective in increasing the firm’s value, and in changing the firm’s chief executive officer (CEO) when (1) the controlling shareholder’s voting power is leveraged, or (2) when the CEO assumes a position on the board of directors simultaneously. We interpreted that these results are in line with the arguments in favor of the existence of a new agency cost, which is related to the undue obedience of board members to authority, such as the largest controlling shareholder or the CEO in Brazilian listed firms.  相似文献   
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