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51.
We present an axiomatic derivation of a model proposed by Haken, Kelso, and Bunz (1985) that describes dynamical aspects of the rhythmic coordination between two limbs. Elaboration of this model has included a symmetry parameter that captures the coordination consequences of an inherent or imposed frequency difference between the limbs. We modified one of the axioms involved in the model derivation, a symmetry axiom, in order to incorporate a new symmetry parameter. This new parameter defines a shift between (a) the laboratory coordinate system, in which the behavior is observed, and (b) a second, postulated coordinate system. It is this second coordinate system, in which the relevant state dynamics is assumed to take place and in which the state dynamics evolves under the impact of an attractor. The state dynamics as described in the attractor coordinate system is then mapped by means of the new symmetry parameter to the laboratory coordinate system. We discuss analytically the bifurcation diagram of the model and determine main effects and interaction effects of manipulations related to the symmetry parameters and related to the mode of coordination (in-phase and anti-phase). The theoretical results are brought to bear on the challenging experimental observation that concurrent cognitive activity (counting, encoding, retrieving, sentence analysis) changes the location of the bimanual coordination attractor but not its strength. The theoretical results suggest that cognitive activity may have the effect it has because it shifts the attractor coordinate system relative to the laboratory coordinate system.  相似文献   
52.
We extend cross‐domain research by examining sleep, a domain within the larger nonwork domain that competes for time with work and family domains. We draw from scarcity theory and research on slack resources to contend that, because people cannot increase the amount of time they have, they borrow time from sleep in order to spend more time working and with family. Utilizing a Bureau of Labor Statistics survey of 10,741 participants, we find nonlinear and interactive effects of time spent working and time spent with family on sleep time, suggesting that the negative effects of work and family on sleep time are especially strong when demands for work and family are high. In an experience sampling field study of 122 working adults, we similarly find a nonlinear effect of work time on sleep time as well as an interaction between work time and family time in predicting time spent sleeping. Both studies indicate that as slack time resources become increasingly scarce, time spent working and time spent with family have increasingly powerful negative effects on time spent sleeping. Contrary to our expectations, we found no support for gender as a moderator of these effects.  相似文献   
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Whole genome sequencing (WGS) is being used for evaluation of individuals with undiagnosed disease of suspected genetic origin. Implementing WGS into clinical practice will place an increased burden upon care teams with regard to pre-test patient education and counseling about results. To quantitate the time needed for appropriate pre-test evaluation of participants in WGS testing, we documented the time spent by our clinical research group on various activities related to program preparation, participant screening, and consent prior to WGS. Participants were children or young adults with autism, intellectual or developmental disability, and/or congenital anomalies, who have remained undiagnosed despite previous evaluation, and their biologic parents. Results showed that significant time was spent in securing allocation of clinical research space to counsel participants and families, and in acquisition and review of participant’s medical records. Pre-enrollment chart review identified two individuals with existing diagnoses resulting in savings of $30,000 for the genome sequencing alone, as well as saving hours of personnel time for genome interpretation and communication of WGS results. New WGS programs should plan for costs associated with additional pre-test administrative planning and patient evaluation time that will be required to provide high quality care.  相似文献   
55.
To date, the majority of research on emotional labor has focused on outcomes that occur in the workplace. However, research has yet to consider the possibility that the daily effects of emotional labor spill over to life outside of work, even though a large body of literature examining the spillover from work life to home life indicates that work experiences influence employees after they leave the workplace. Accordingly, we examined the influence of day‐to‐day surface acting on 3 types of theoretically derived stress outcomes experienced at home: emotional exhaustion, work‐to‐family conflict, and insomnia. In an experience sampling field study of 78 bus drivers, we found that daily surface acting was connected to increases in each of the outcomes noted above. Moreover, surface acting had an indirect effect on emotional exhaustion and insomnia via state anxiety.  相似文献   
56.
This study sought to replicate the results of our earlier study, which were published in this Journal (Willoughby et. al 2011), that used mother-reported items from the Achenbach System of Empirically Based Assessment to develop a screening measure of callous unemotional (CU) behaviors for use with preschool-aged children. We further sought to extend those results by exploring the predictive validity of the CU measure with aggression trajectories in early-/mid- childhood. The current study involved secondary data analysis of the NICHD Study of Early Childhood and Youth Development (NICHD-SECCYD) dataset. Factor analyses included N?=?1,176 children who participated in the age 3 year assessment of the NICHD-SECCYD. Predictive models included N?=?1,081 children for whom four of the six possible teacher ratings of aggressive behavior were available from annual assessments spanning 1st–6th grades. Consistent with prior work, a three-factor confirmatory factor model, which differentiated CU from oppositional defiant (ODD) and attention deficit/hyperactive-impulsive (ADHD) behaviors, provided the best fit to the data. Among children with disorganized attachment status, the combination of high levels of mother-rated ODD behaviors and CU behaviors, was predictive of stable elevated levels of teacher-rated aggression from 1st–6th grade (predicted probability?=?0.38, compared with a base rate of 0.07). These results demonstrate that CU behaviors can be reliably measured by parent report in young children and are dissociable from more commonly assessed dimensions of disruptive behavior. Three-year-old children who exhibit elevated levels of ODD and CU behaviors, and who have disorganized attachments, are at increased risk for exhibiting elevated levels of aggression across middle childhood. Results are discussed from the perspective of early assessment and intervention.  相似文献   
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We provide an initial evaluation of the factor structure of the Impact of Event Scale-Revised (IES-R) when used with a volunteer firefighter and a similar community participant sample. A volunteer firefighter sample (n = 65) and a sample of similar community respondents (n = 103) completed a questionnaire study, including responses to the IES-R. The IES-R data from both groups were entered into a three-factor principal components analysis with direct oblimin rotation. We found further support for the validity of the IES-R when used with a community sample. However, our data suggested that when using the IES-R with a community sample, the choice between a two- and a three-factor model may depend on the composition of the participants. For volunteer firefighters, the factor-analytic structure of the IES-R appeared to be similar to that of the community sample, with more scatter in terms of item loadings. To our knowledge, there is no previous research considering the use of the IES-R with a strictly volunteer firefighter sample. In addition, despite adequate research on the factor-analytic structure of the original IES, little research has considered the factor-analytic structure of the more recent IES-R, even with community samples.  相似文献   
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The principal accepted models of posttraumatic stress disorder (PTSD) are based on both memory processing and biological/brain changes occurring when one's life or well-being is threatened. It is our thesis that these models would be greatly informed by community studies indicating that PTSD is predicted to a greater extent by earlier life experience and experiences that occur distant from the threatening event. These findings suggest posttraumatic responding is best conceptualized through the lens of the self-in-context, as opposed to imprinting that results from a given event at a given time. Moreover, studies of non-Western populations often do not express trauma as PTSD, or at least not primarily as PTSD, which argues against specific neural or memory encoding processes, but rather for a more plastic neural process that is shaped by experience and how the self develops in its cultural context, as a product of a broad array of experiences. We posit that fear and emotional conditioning as well as the ways traumas are encoded in memory are only partial explanatory mechanisms for trauma responding, and that issues of safety and harm, which are long term and developmental, are the common and principal underpinnings of the occurrence of posttraumatic distress, including PTSD.  相似文献   
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