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Many individuals with autism spectrum disorder (ASD) exhibit motor difficulties, but it is unknown whether manual motor skills improve, plateau, or decline in ASD in the transition from childhood into adulthood. Atypical development of manual motor skills could impact the ability to learn and perform daily activities across the life span. This study examined longitudinal grip strength and finger tapping development in individuals with ASD (= 90) compared to individuals with typical development (= 56), ages 5 to 40 years old. We further examined manual motor performance as a possible correlate of current and future daily living skills. The group with ASD demonstrated atypical motor development, characterized by similar performance during childhood but increasingly poorer performance from adolescence into adulthood. Grip strength was correlated with current adaptive daily living skills, and Time 1 grip strength predicted daily living skills eight years into the future. These results suggest that individuals with ASD may experience increasingly more pronounced motor difficulties from adolescence into adulthood and that manual motor performance in ASD is related to adaptive daily living skills.  相似文献   
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A series of experiments was designed to explore the cognitive mechanisms involved in optimal foraging models by using the behavioural controls of operant methodology. Rats were trained to press one of two levers to obtain reinforcement on a progressive variable-interval schedule, which modelled food patch depletion; the schedule was reset by pressing the other lever. Thus both duration (residence time in a patch) and rate-related (interval before and after the final reward) measures were obtained. Experiment 1, which manipulated environmental stability and quality, and Experiment 2, which varied travel time between patches, found results that supported the marginal value theorem (Charnov, 1976) and suggested that rats adjust capture rate to the environment average by monitoring the length of the interval between rewards. Experiment 3 modelled the clumping of food items and found that capture rate was now adjusted by adoption of a fixed giving-up time. Finally, Experiments 4a and 4b ruled out a time expectancy hypothesis by manipulating the number of food clumps and the series of inter-reinforcement intervals. Overall the experiments demonstrate the value of modelling foraging strategies in operant apparatus, and suggest that rats adopt rate predictive strategies when deciding to switch patches.  相似文献   
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Although dating violence is widespread among young adult homeless populations, its risk factors are poorly understood by scholars. To address this gap, this study uses a social learning theory to examine the effects of abusive parenting and caretaker arrests on dating violence among 172 homeless young adults. Results from path analyses revealed that child physical abuse and caretaker arrests were positively associated with engaging in a greater number of school fights, which, in turn, was strongly and positively correlated with participating in more deviant subsistence strategies (e.g., stealing) since being on the street. Young people who participated in a greater number of delinquent acts were more likely to report higher levels of dating violence. Study results highlight the extent of social learning within the lives of homeless young adults, which is evident prior to their leaving home and while they are on the street.  相似文献   
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Bullying involvement is a multidimensional issue and a significant concern for school-aged youth. However, research on bullying involvement within clinical samples is limited. The present study examines the psychometric properties of the University of Illinois Bully, Fighting, and Victimization Scales among children and adolescents presenting for mood symptoms at a behavioral health outpatient clinic. Patients (n = 165) with an age range of 8–18 years were included in this investigation. Item frequencies, internal consistency, and construct validity were examined while confirmatory and exploratory factor analyses were conducted. Results showed that the scales were low to moderately correlated with each other. Internal consistencies were acceptable for the Bully (α = .70), Fighting (α = .84), and Victimization (α = .88) Scales. Exploratory factor analysis revealed clean three-factor solutions with items loading on their intended factors and with few cross-loadings. Fit of the confirmatory factor analysis was good when items were treated as ordinal and two items were allowed to cross-load on more than one factor. The University of Illinois Bully, Fighting, and Victimization Scales show utility for use with clinically referred youth.  相似文献   
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Fred Dretske, Michael Tooley, and David Armstrong accept a theory of governing laws of nature according to which laws are atomic states of affairs that necessitate corresponding natural regularities. Some philosophers object to the Dretske/Tooley/Armstrong theory on the grounds that there is no illuminating account of the necessary connection between governing law and natural regularity. In response, Michael Tooley has provided a reductive account of this necessary connection in his book Causation (1987). In this essay, I discuss an improved version of his account and argue that it fails. First, the account cannot be extended to explain the necessary connection between certain sorts of laws—namely, probabilistic laws and laws relating structural universals—and their corresponding regularities. Second, Tooley’s account succeeds only by (very subtly) incorporating primitive necessity elsewhere, so the problem of avoiding primitive necessity is merely relocated.  相似文献   
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