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271.
Studies have suggested that proper postural control is essential for the development of reaching. However, little research has examined the development of the coordination between posture and manual control throughout childhood. We investigated the coordination between posture and manual control in children (7- and 10-year-olds) and adults during a precision fitting task as task constraints became more difficult. Participants fit a block through an opening as arm kinematics, trunk kinematics, and center of pressure data were collected. During the fitting task, the precision, postural, and visual constraints of the task were manipulated. Young children adopted a strategy where they first move their trunk toward the opening and then stabilize their trunk (freeze degrees of freedom) as the precision manual task is being performed. In contrast, adults and older children make compensatory trunk movements as the task is being performed. The 10-year-olds were similar to adults under the less constrained task conditions, but they resembled the 7-year-olds under the more challenging tasks. The ability to either suppress or allow postural fluctuations based on the constraints of a suprapostural task begins to develop at around 10 years of age. This ability, once developed, allows children to learn specific segmental movements required to complete a task within an environmental context.  相似文献   
272.
One aim of this study was to apply information theoretical analyses to understanding the structural complexity of chick-a-dee calls of Carolina chickadees, Poecile carolinensis. A second aim of this study was to compare this structural complexity to that of the calls of black-capped chickadees, P. atricapillus, described in an earlier published report (Hailman, Ficken, & Ficken, 1985). Chick-a-dee calls were recorded from Carolina chickadees in a naturalistic observation study in eastern Tennessee. Calls were analyzed using approaches from information theory, including transition probability matrices, Zipf's rules, entropies, and information coding capacities of calls and notes of calls. As described for black-capped chickadees, calls of Carolina chickadees exhibited considerable structural complexity. Most results suggested that the call of Carolina chickadees is more structurally complex than that of black-capped chickadees. These findings add support to the growing literature on the complexity of this call system in Paridae species. Furthermore, these results point to the feasibility of detailed cross-species comparative analyses that may allow strong testing of hypotheses regarding signal evolution.  相似文献   
273.
Little empirical knowledge about unemployed adults exists during a time when this group needs substantial career assistance. Because there is greater empirical understanding of college student career development compared with what is known about unemployed adults, a chi square and analyses of covariance were used to compare the career thinking, self‐efficacy, and interests of 169 unemployed adults seeking public job center assistance with that of 200 college students. Additionally, a diverse sample of 2,444 unemployed adults is demographically reviewed. Unemployed adults reported a higher level of Realistic interests and similar levels of negative career thinking and career decision‐making self‐efficacy compared with college students.  相似文献   
274.
Instructors of the visually impaired need efficient braille‐training methods. This study conducted a preliminary evaluation of a computer‐based program intended to teach the relation between braille characters and English letters using a matching‐to‐sample format with 4 sighted college students. Each participant mastered matching visual depictions of the braille alphabet to their printed‐word counterparts. Further, each participant increased the number of words they read in a braille passage following this training. These gains were maintained at variable levels on a maintenance probe conducted 2 to 4 weeks after training.  相似文献   
275.
When forming impressions about other people, stereotypes about the individual's social group often influence the resulting impression. At least 2 distinguishable processes underlie stereotypic impression formation: stereotype activation and stereotype application. Most previous research has used implicit measures to assess stereotype activation and explicit measures to assess stereotype application, which has several disadvantages. The authors propose a measure of stereotypic impression formation, the stereotype misperception task (SMT), together with a multinomial model that quantitatively disentangles the contributions of stereotype activation and application to responses in the SMT. The validity of the SMT and of the multinomial model was confirmed in 5 studies. The authors hope to advance research on stereotyping by providing a measurement tool that separates multiple processes underlying impression formation.  相似文献   
276.
This article argues for two related theses. First, it defends a general thesis: any kind of necessity, including metaphysical necessity, can only be known a priori. Second, however, it also argues that the sort of a priori involved in modal metaphysical knowledge is not related to imagination or any sort of so‐called epistemic possibility. Imagination is neither a proof of possibility nor a limit to necessity. Rather, modal metaphysical knowledge is built on intuition of philosophical categories and the structures they form.  相似文献   
277.
This longitudinal study among ethnic migrants from Russia to Finland (N = 127) examined the relationships between anticipated and perceived discrimination, ethnic and national identities, and outgroup attitudes towards the national majority group. The study included one pre‐migration and two post‐migration assessments. First, associations between the variables studied were tested using a conventional autoregressive sample‐level modelling approach. Second, individual trajectories and the associations between the individual‐level changes in the variables included in the models were tested. Although there were no sample‐level effects over time, there were significant relationships between changes in discrimination and changes in identification and outgroup attitudes at the individual level. The results indicated that changes in perceived discrimination were not reflected in increased ethnic identification. However, participants who perceived higher levels of discrimination after migration than they anticipated before migration were, in the post‐migration stage, more likely to disidentify from and to increasingly show negative attitudes towards the national majority group. The study complements previous research by examining the identity and attitudinal reactions to perceived ethnic discrimination starting from the pre‐migration stage and highlights the value of incorporating both group and individual perspectives to the research on perceived discrimination. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
278.
A principal challenge for a deflationary theory is to explain the value of truth: why we aim for true beliefs, abhor dishonesty, and so on. The problem arises because deflationism sees truth as a mere logical property and the truth predicate as serving primarily as a device of generalization. Paul Horwich, attempts to show how deflationism can account for the value of truth. Drawing on the work of J. L. Austin, I argue that his account, which focuses on belief, cannot adequately accommodate the complex role that truth plays in the norms governing assertion and similar speech acts.  相似文献   
279.
Although children born preterm or low birth weight (PT LBW) are more likely to exhibit behavior problems compared to children born at term, developmental and family processes associated with these problems are unclear. We examined trajectories of maternal depressive symptoms in relation to toddler compliance and behavior problems in families with PT LBW infants. A total of 177 infants (93 boys, 84 girls) and their mothers enrolled in the study during the infant's NICU stay. Data were collected at five time points across 2 years. Assessments of maternal depressive symptoms were conducted at all time points, and toddler compliance and opposition to maternal requests and behavior problems were assessed at 2 years. Toddlers born earlier with more health problems to mothers whose depressive symptoms increased over time exhibited the most opposition to maternal requests during a cleanup task at 24 months, consistent with multiple risk models. Mothers with elevated depression symptoms reported more behavior problems in their toddlers. The study has implications for family‐based early intervention programs seeking to identify PT LBW infants at highest risk for problem behaviors.  相似文献   
280.
Socially disinhibited or indiscriminate behavior (IB) has traditionally been investigated using caregiver reports. More recently, an observational measure based on the Strange Situation Procedure (M. Ainsworth, M. Blehar, E. Waters, & S. Wall, 1978), the Rating of Infant and Stranger Engagement (RISE; C. Riley, A. Atlas‐Corbett, & K. Lyons‐Ruth, 2005), was validated in home‐reared at‐risk children. The present study aimed to validate the RISE in an institutionally reared sample using the caregiver report, to assess whether IB assessed with the RISE was elevated among the institutionalized children, and to explore potential risk factors associated with IB. The study was conducted among 74 institutionalized toddlers aged 11 to 30 months. Sociodemographic questionnaires were used to assess pre‐admission experiences, and aspects of institutional placement were coded from the children's files in the institution and staff's report. Institutionalized children displayed high frequencies of IB as assessed on the RISE, and this instrument was validated against caregiver report. Pre‐admission experiences of the institutionalized children in their biological families—namely, prenatal risk and maternal emotional neglect risk—predicted IB. Results suggest that the RISE is adequate to use among institutionally reared toddlers and point to aspects of the early familial environment that may be implicated in IB.  相似文献   
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