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1.
    
Federal and other regulatory agencies often use or claim to use a weight of evidence (WoE) approach in chemical evaluation. Their approaches to the use of WoE, however, differ significantly, rely heavily on subjective professional judgment, and merit improvement. We review uses of WoE approaches in key articles in the peer‐reviewed scientific literature, and find significant variations. We find that a hypothesis‐based WoE approach, developed by Lorenz Rhomberg et al., can provide a stronger scientific basis for chemical assessment while improving transparency and preserving the appropriate scope of professional judgment. Their approach, while still evolving, relies on the explicit specification of the hypothesized basis for using the information at hand to infer the ability of an agent to cause human health impacts or, more broadly, affect other endpoints of concern. We describe and endorse such a hypothesis‐based WoE approach to chemical evaluation.  相似文献   
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A common assumption in meta‐analysis is that effect sizes are independent. When correlated effect sizes are analyzed using traditional univariate techniques, this assumption is violated. This research assesses the impact of dependence arising from treatment‐control studies with multiple endpoints on homogeneity measures Q and I2 in scenarios using the unbiased standardized‐mean‐difference effect size. Univariate and multivariate meta‐analysis methods are examined. Conditions included different overall outcome effects, study sample sizes, numbers of studies, between‐outcomes correlations, dependency structures, and ways of computing the correlation. The univariate approach used typical fixed‐effects analyses whereas the multivariate approach used generalized least‐squares (GLS) estimates of a fixed‐effects model, weighted by the inverse variance–covariance matrix. Increased dependence among effect sizes led to increased Type I error rates from univariate models. When effect sizes were strongly dependent, error rates were drastically higher than nominal levels regardless of study sample size and number of studies. In contrast, using GLS estimation to account for multiple‐endpoint dependency maintained error rates within nominal levels. Conversely, mean I2 values were not greatly affected by increased amounts of dependency. Last, we point out that the between‐outcomes correlation should be estimated as a pooled within‐groups correlation rather than using a full‐sample estimator that does not consider treatment/control group membership. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
3.
    
It has been suggested that the motivation to spend effort is decreased in burnout patients, resulting in reduced cognitive performance. A question that remains is whether this decreased motivation can be reversed by motivational interventions. We investigated this by examining the effect of a motivational intervention on cognitive performance. We presented 40 burnout patients in The Netherlands and 40 matched healthy controls with a complex attention task. As expected, in a first block of trials the performance of the burnout patients was poorer than that of healthy controls. Subsequently, we provided the participants with fake positive feedback about their performance and announced that we would financially reward those who performed best in a subsequent block of trials. Contrary to the healthy controls, the burnout patients did not improve their performance and experienced more aversion to spend effort. The study demonstrated that impaired cognitive performance in burnout patients could not be reversed by motivational interventions, which is in line with contemporary theories on burnout that state that physiological changes in burnout may underlie a relatively long-term decrease in motivation. The implication of these results is that in practice employers and therapists might need to accept that there could be a reduction in cognitive performance in employees with burnout.  相似文献   
4.
    
Absorptive capacity is frequently highlighted as a key determinant of knowledge transfer within multinational enterprises. But how individual behaviour translates into absorptive capacity at the subsidiary level, and how this is contingent on subsidiaries' social context, remains under‐addressed. This not only limits our understanding of the relationship between individual‐ and organizational‐level absorptive capacity, but also hampers further research on potentially relevant managerial and organizational antecedents, and limits the implications we can draw for practitioners who seek to increase their organization's capacity to put new knowledge to use. To address this shortcoming we conduct an in‐depth comparative case study of a headquarters‐initiated knowledge transfer at two subsidiaries of the same multinational enterprise. The findings demonstrate that social interaction is a prerequisite for subsidiary absorptive capacity as it enables employees to participate in the transformation of new knowledge to the local context and the development of local applications. The findings also illustrate how organizational conditions at the subsidiary level can impact subsidiary absorptive capacity by enabling or constraining local interaction patterns. These insights contribute to the absorptive capacity literature by demonstrating the scale and scope of social interaction as a key link between individual‐ and organizational‐level absorptive capacity.  相似文献   
5.

Background

Real-world fall events objectively measured by body-worn sensors can improve the understanding of fall events in older people. However, these events are rare and hence challenging to capture. Therefore, the FARSEEING (FAll Repository for the design of Smart and sElf-adaptive Environments prolonging Independent livinG) consortium and associated partners started to build up a meta-database of real-world falls.

Results

Between January 2012 and December 2015 more than 300 real-world fall events have been recorded. This is currently the largest collection of real-world fall data recorded with inertial sensors. A signal processing and fall verification procedure has been developed and applied to the data. Since the end of 2015, 208 verified real-world fall events are available for analyses. The fall events have been recorded within several studies, with different methods, and in different populations. All sensor signals include at least accelerometer measurements and 58 % additionally include gyroscope and magnetometer measurements. The collection of data is ongoing and open to further partners contributing with fall signals. The FARSEEING consortium also aims to share the collected real-world falls data with other researchers on request.

Conclusions

The FARSEEING meta-database will help to improve the understanding of falls and enable new approaches in fall risk assessment, fall prevention, and fall detection in both aging and disease.
  相似文献   
6.
Becker  Marina  Buchholz  Sascha 《Urban Ecosystems》2016,19(1):361-372
Urban Ecosystems - Urbanisation can be dangerous to biological diversity, but on the other hand cities can enhance local and regional biodiversity by providing habitat analogues for many –...  相似文献   
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8.
The present contribution shows conceptual and methodological approaches for the study of social context effects within families. Family members mutually constitute the social context in which family behavior and personality development take place. Social influence in families becomes evident empirically in family members’ significant similarity concerning a wide variety of characteristics. The present study focuses on intrafamily convergence with regard to religiousness. In an empirical illustration, both (a) horizontal intracouple alignment and (b) vertical intergenerational transmission processes are examined. Besides the finding that experiences during religious socialization in the parental home have a stronger impact than partner influences in adulthood, our analyses show that social context effects are more pronounced the stronger the cohesion of the respective interaction dyad is (e.g., according to measures of relationship quality).  相似文献   
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10.
Increased physical activity is positively associated with better health in community-dwelling older persons. It is unclear whether physical activity also influences success of inpatient rehabilitation. For the assessment of physical activity in inpatient rehabilitation the Physical Activity in Inpatient Rehabilitation Assessment (PAIR), a short questionnaire based on five questions, was developed and preliminary validated. In this study, the PAIR was validated against a sensor-based physical activity measurement. Seventy functionally impaired and cognitively mostly intact patients of a German geriatric inpatient rehabilitation clinic who had undergone hip surgery (n?=?62 women, median age?=?83 years) participated. Physical activity was measured using the PAIR and a sensor-based activity monitor (Physilog ®; BioAGM, CH). Assessments were conducted at admission (T1) and 2 weeks later (T2) during the rehabilitation process. To assess concurrent and predictive validity, Spearman correlations and linear regression models were calculated using sensor-based walking activity and uptime activity (walking and standing time) as dependent variables. Criterion-related concurrent validity using physical activity sensors was weak to moderate. Correlations were slightly higher at T2 (r?=?0.45-0.53) than at T1 (r?=?0.44-0.46). The objectively measured variance of physical activity, explained by the PAIR, ranged from 25 to 43 %. PAIR activity scores and sensor-based walking or total activity increased in a dose-dependent manner, confirming the scoring system of the PAIR. The application time was usually less than 2 min. The validity of the PAIR is weak to moderate when compared to a sensor-based activity monitor and comparable to existing physical activity assessments for community-dwelling older adults.  相似文献   
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