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71.
Behavior analysis has been at the forefront in establishing effective treatments for children and adults with chronic tic disorders. As is customary in behavior analysis, the efficacy of these treatments has been established using direct-observation assessment methods. Although behavior-analytic treatments have enjoyed acceptance and integration into mainstream health care practices for tic disorders (e.g., psychiatry and neurology), the use of direct observation as a primary assessment tool has been neglected in favor of less objective methods. Hesitation to use direct observation appears to stem largely from concerns about the generalizability of clinic observations to other settings (e.g., home) and a lack of consensus regarding the most appropriate and feasible techniques for conducting and scoring direct observation. The purpose of the current study was to evaluate and establish a reliable, valid, and feasible direct-observation protocol capable of being transported to research and clinical settings. A total of 43 children with tic disorders, collected from two outpatient specialty clinics, were assessed using direct (videotape samples) and indirect (Yale Global Tic Severity Scale; YGTSS) methods. Videotaped observation samples were collected across 3 consecutive weeks and two different settings (clinic and home), were scored using both exact frequency counts and partial-interval coding, and were compared to data from a common indirect measure of tic severity (the YGTSS). In addition, various lengths of videotaped segments were scored to determine the optimal observation length. Results show that (a) clinic-based observations correspond well to home-based observations, (b) brief direct-observation segments scored with time-sampling methods reliably quantified tics, and (c) indirect methods did not consistently correspond with the direct methods.  相似文献   
72.
Early locomotor behavior has been the focus of considerable attention by developmentalists over several decades. Few studies have addressed explicitly patterns of muscle activity that underlie this coordination pattern. Our purposes were to illustrate a method to determine objectively the onset and offset of muscle firings during early walking and to investigate the emergence of patterns of activation of the core locomotor muscles. We tested eight toddlers as they walked overground at walking onset (max. of 3-6 independent steps) and after three months of walking experience. Surface electrodes monitored activity of the gastrocnemius, tibialis anterior, quadriceps, and hamstrings. We reduced EMG signals to a frame-by-frame designation of "on-off," followed by muscle state and co-contraction analyses, and probability distributions for each muscle's activity across multiple cycles. Our results clearly show that at walking onset muscle activity was highly variable with few, if any, muscles showing recurring patterns of behavior, within or among toddlers. Variability and co-activation decreased with walking experience but remained inconsistent, in contrast to the significant increase in stability shown for joint coordination and endpoint (foot placement) parameters. We propose this trend emerges because of the high number of options (muscle combinations) available. Toddlers learn first to marshal sufficient force to balance and make forward progress but slowly discover how to optimize these resources.  相似文献   
73.
Previous research has emphasized the role of within-match similarity in children's comparisons. The current study investigated another potentially important contributing factor, namely the distinctiveness of the matching items relative to other items in the scene. Using a well-known relational mapping task, we found that 3- and 4-year-olds made more correct matches between identical objects when those objects were maximally distinctive from the foils. In a cross-mapping experiment, where same relative size was pitted against object similarity, 3-year-olds made more incorrect object matches when the objects were both similar to each other and distinctive from the foils. Furthermore, 3- and 4-year-olds performed the same, regardless of within-match similarity, so long as the ratios of within-match and nonmatch similarity were roughly equal. These findings suggest that children's comparisons are guided by a ratio consisting of many pairwise similarity relations, including (but not limited to) the degree of within-match similarity.  相似文献   
74.
This paper considers a family of inductive problems where reasoners must identify familiar categories or features on the basis of limited information. Problems of this kind are encountered, for example, when word learners acquire novel labels for pre-existing concepts. We develop a probabilistic model of identification and evaluate it in three experiments. Our first two experiments explore problems where a single category or feature must be identified, and our third experiment explores cases where participants must combine several pieces of information in order to simultaneously identify a category and a feature. Humans readily solve all of these problems, and we show that our model accounts for human inferences better than several alternative approaches.  相似文献   
75.
The current study applies semantic differential to explore the semantic perception of emergency signs, in an attempt to analyze the meanings of emergency signs in regard to the psychological exigencies of the general public. The results indicate that problems concerning recognition accuracy have been observed, but also that the evaluation of the semantic meaning of the signs is positive. However, a number of emotional factors also emerge, indicating that if improvements should be made to the existing emergency signs, it would better facilitate evacuation in the event of an emergency. As for the design guidelines, the emergency signs should be readily recognizable and have a single meaning. Multiple symbolic meanings should be eliminated. Concrete design guidelines include: (a) safety movement, (b) clarity, and (c) safety. To avoid confusion in sign recognition, in addition to the improvements made based on the abovementioned guidelines, educational promotional activities carried out by the government would also prove very beneficial.  相似文献   
76.
An enhancement of the UV-visible optical absorption spectra of Ag nanoparticles (NPs) deposited on indium tin oxide (ITO) surfaces of different resistance by a seed-mediated growth technique is presented. A bicolour coherent beam, obtained from a pulsed Nd:YAG laser providing a 1060-nm fundamental wavelength and a double-frequency one at 530?nm, was used. A significant change in the optical density is observed for Ag NPs on low-resistance ITO surfaces (≈4?Ω/square), while almost nothing occurs with high-resistance (≈50?Ω/square surfaces). The spectral position of the maximal absorption at 440?nm is almost preserved in both cases. This result is explained in terms of a local photoinduced static field and surface-plasmon polaritons interacting with photoexcited phonons. A grating effect, arising from the coherent bicolour light forming a superstructure as for quantum crystals, could be another contribution.  相似文献   
77.
78.
Past research has attempted to delineate personality differences between insomniacs and good sleepers but has failed to control for type of insomnia or severity of the disorder. The purpose of this study was to compare MMPI scores of mild and severe sleep onset insomniacs with a control group of noninsomniacs. Results demonstrated that sleep onset insomniacs, regardless of degree of severity, differed significantly from noninsomniacs; and that mild and severe insomniacs differed from each other on only one MMPI scale.  相似文献   
79.
This study surveyed 1,156 practicing US physicians to examine the relationship between physicians’ religious characteristics and their approaches to artificial nutrition and hydration (ANH). Forty percent of physicians believed that unless a patient is imminently dying, the patient should always receive nutrition and fluids; 75 % believed that it is ethically permissible for doctors to withdraw ANH. The least religious physicians were less likely to oppose withholding or withdrawing ANH. Compared to non-evangelical Protestant physicians, Jews and Muslims were significantly more likely to oppose withholding ANH, and Muslims were significantly more likely to oppose withdrawing ANH.  相似文献   
80.
We tested the effects of team strategic orientation on team member perceptions, work strategy and information search. In Experiment 1, 80 teams worked on a hidden profile decision-making task. A defensive team strategic orientation increased members’ perceptions of the problem’s scope, leading to a more process-focused work strategy and broader information search compared to an offensive team strategic orientation. When teams needed critical information from the environment, defensive teams outperformed offensive teams; offensive teams performed better when critical information resided within the team. In Experiment 2, these findings were replicated with 92 teams performing a different decision task. When making a second decision, half of the teams were led to change their strategic orientation; teams shifting from offense to defense altered their information search behavior more readily than did teams shifting in the opposite direction, suggesting an asymmetric adaptation effect.  相似文献   
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