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161.
The effects of fixed-time (FT) reinforcement schedules on the disruptive behavior of 4 students in special education classrooms were studied. Attention provided on FT schedules in the context of a multiple-baseline design across participants substantially decreased all students’ challenging behavior. Disruptive behavior was maintained at levels lower than baseline throughout reinforcement thinning and follow-up phases. The results extend existing literature on the use of FT schedules of reinforcement and provide evidence that FT schedules of reinforcement can be practical to implement in special educational classroom settings.  相似文献   
162.
Few programs exist for after school care designed to support children with Autism Spectrum Disorder (ASD). Not only do parents often depend on after school care, but also children with ASD are likely to benefit from opportunities to generalize skills in an authentic setting and interact with typically developing peers. This lack of support occurs at a time during which there is increasing research and community awareness regarding the need for high quality after school programs to support typically developing children. This study investigates reported experiences with and needs for after school care by parents of children with ASD. Survey results (N = 54) revealed that the majority of parents surveyed desired after school programs within their child’s school but are often denied access to such services or received low quality care for their child in after school programs. Recommendations are provided for future research and program development.  相似文献   
163.
With increasing popularity, growth curve modeling is more and more often considered as the 1st choice for analyzing longitudinal data. Although the growth curve approach is often a good choice, other modeling strategies may more directly answer questions of interest. It is common to see researchers fit growth curve models without considering alterative modeling strategies. In this article we compare 3 approaches for analyzing longitudinal data: repeated measures analysis of variance, covariance pattern models, and growth curve models. As all are members of the general linear mixed model family, they represent somewhat different assumptions about the way individuals change. These assumptions result in different patterns of covariation among the residuals around the fixed effects. In this article, we first indicate the kinds of data that are appropriately modeled by each and use real data examples to demonstrate possible problems associated with the blanket selection of the growth curve model. We then present a simulation that indicates the utility of Akaike information criterion and Bayesian information criterion in the selection of a proper residual covariance structure. The results cast doubt on the popular practice of automatically using growth curve modeling for longitudinal data without comparing the fit of different models. Finally, we provide some practical advice for assessing mean changes in the presence of correlated data.  相似文献   
164.
165.
Bio-technology has become a new impeller to the development of the world economy since the 1970's. The development of bio-economy has two sides for mankind which calls for intervention by law. During the legislation of bioeconomy, some special principles should be esteemed and observed by legislators. It is necessary for the healthy development of bio-economy.  相似文献   
166.
Contemporary optimization models suggest that animals optimize benefits of foraging and minimize its costs. For wild bearded capuchins (Sapajus libidinosus), nut-cracking entails cost related to lifting the heavy stone and striking the nut and additional cost to transport the stone if it is not already on the anvil. To assess the role of stone mass and transport distance in capuchins’ tool selection, we carried out three field experiments. In Experiment 1, we investigated whether transport distance affected choice of a tool by positioning two stones of the same mass close and far from the anvil. Capuchins consistently selected the closer stone, effectively reducing transport costs. In Experiment 2, we examined the trade-off between the cost of transport and the effectiveness in cracking by positioning two stones of different mass close and far from the anvil. Most subjects significantly preferred the closer stone, regardless of mass, whereas others preferred the heavier stone regardless of transport distance. In Experiment 3, we changed transport distance of both stones while maintaining the same distance ratios as in Experiment 2. Capuchins maintained the preferences expressed in Experiment 2, with the exception of one subject. Overall, our findings indicate that (1) individuals vary in their sensitivity to distance of transport, (2) a few meters are perceived as a substantive cost by some monkeys, and (3) monkeys’ body mass affects their decisions. We also developed a non-dimensional Preference index (P) defined as a function of the stone mass and the transport distance to describe monkey’s choice.  相似文献   
167.
Recalling positive autobiographical memories is a powerful emotion regulation strategy that can be used to repair low mood and alleviate negative affect. Unlike healthy individuals, those with current or past depression do not experience an improvement in mood as a consequence of recalling positive memories. We tested whether differences in processing mode might account for this impairment. Following mood induction procedures designed to ensure equivalence of mood state, depressed (n = 35) and recovered depressed (n = 33) participants were instructed to recall a positive memory and focus on it while adopting either an abstract or a concrete mode of processing. Participants in the abstract processing condition experienced no change in mood, while those in the concrete processing condition showed improved mood after memory recall. This research illustrates that the process by which positive autobiographical memories are recalled is important in determining their emotional impact and suggests that psychological interventions for depression may be improved by explicitly targeting processing mode.  相似文献   
168.
Elevated internalized stigma is common and is linked to subjective and objective outcomes for severe mental illness. The authors developed a manualized group-based intervention (Narrative Enhancement/Cognitive Therapy; NECT) to address internalized stigma in severe mental illness. The purpose of the present study was to evaluate the feasibility and effectiveness of NECT. In total, 144 individuals were screened at two sites to evaluate if they met criteria for "elevated" internalized stigma; 39 and were eligible were randomized to NECT or to treatment as usual (TAU) and were assessed at baseline, posttreatment, and 3-month follow-up. Fifteen of the 21 individuals assigned to NECT were classified as "exposed" to treatment. Intent-to-treat analyses found no significant difference between the NECT and TAU groups. A comparison of exposed versus unexposed participants noted trends for exposed participants to have improved more in two aspects of self-stigma as well as insight. We conclude that NECT is feasible and tolerable, but findings did not support the hypothesis that NECT was more effective than TAU, although small sample size and significant dropout may have restricted the ability to detect an effect.  相似文献   
169.
The current study evaluated the degree to which startle reflexes (SRs) in safe conditions versus danger conditions were predictive of the onset of anxiety disorders. Specificity of these effects to anxiety disorders was evaluated in comparison to unipolar depressive disorders and with consideration of level of neuroticism. A startle paradigm was administered at baseline to 132 nondisordered adolescents as part of a longitudinal study examining risk factors for emotional disorders. Participants underwent a repetition of eight safe-danger sequences and were told that delivery of an aversive stimulus leading to a muscle contraction of the arm would occur only in the late part of danger conditions. One aversive stimulus occurred midway in the safe-danger sequences. Participants were assessed for the onset of anxiety and unipolar depressive disorders annually over the next 3 to 4 years. Larger SR magnitude during safe conditions following delivery of the aversive stimulus predicted the subsequent first onset of anxiety disorders. Moreover, prediction of the onset of anxiety disorders remained significant above and beyond the effects of comorbid unipolar depression, neuroticism, and subjective ratings of intensity of the aversive stimulus. In sum, elevated responding to safe conditions following an aversive stimulus appears to be a specific, prospective risk factor for the first onset of anxiety disorders.  相似文献   
170.
A prospective, behavioral high-risk design provided a theoretically guided examination of vulnerability to first onset of bipolar spectrum disorder based on the Behavioral Approach System (BAS) model. Adolescents (ages 14-19) at an "age of risk" for bipolar disorder onset were screened on BAS sensitivity by interviewers blind to current symptoms, lifetime history, and family history of psychopathology. Participants were selected with high versus moderate levels of BAS sensitivity and administered a lifetime diagnostic interview. Those with a bipolar spectrum disorder, psychosis, or hypomanic episode with onset prior to the BAS sensitivity assessment were excluded. High BAS (n = 171) and moderate BAS (n = 119) sensitivity participants in the final sample completed baseline measures of symptoms, goal-setting, and reward responsiveness and were followed prospectively with semistructured diagnostic interviews every 6 months. Consistent with the vulnerability hypothesis of the BAS model of bipolar disorder, high BAS participants had a greater likelihood, and shorter time to onset, of bipolar spectrum disorder than moderate BAS participants across an average of 12.8 months of follow-up (12.9% vs. 4.2%), controlling for baseline depressive and hypomanic symptoms, and family history of bipolar disorder. High reward responsiveness on a behavioral task and ambitious goal-striving for popular fame and financial success (but not impulsivity) also predicted first onset of bipolar spectrum disorder controlling for the covariates and BAS risk group, and ambitious goal-striving partially mediated the BAS risk group effect. We discuss implications of the findings for the BAS model of bipolar disorder and early intervention efforts.  相似文献   
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