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161.
目前临床对抑郁症的诊断仍普遍存在概念不清的现象,甚至抑郁症的诊断有逐渐被泛化的倾向,本文从抑郁症研究历史的角度,通过对抑郁症的概念及分类历史进行回顾,以期能廓清抑郁症相关的一些概念,从而为进一步统一标准、细化抑郁症的研究提供一些启示。  相似文献   
162.
The present study examined the principles underlying inter and intralimb coordination constraints during performance of bimanual elbow–wrist movements at different cycling frequencies (from 0.75 Hz to 2.50 Hz). Participants performed eight coordination tasks that consisted of a combination of in-phase (IN) and/or anti-phase (AN) coordination modes between both elbows and wrists (interlimb), with isodirectional (Iso) or non-isodirectional (NonI) coordination modes within each limb (intralimb). As expected, the principle of muscle homology (in-phase coordination), giving rise to mirror symmetrical movements with respect to the mid-sagittal plane, had a powerful influence on the quality of global coordinative behavior both between and within limbs. When this principle was violated (i.e., when the anti-phase mode was introduced in one or both joint pairs), the non-isodirectional intralimb mode exhibited a (de)stabilizing role in coordination, which became more pronounced at higher cycling frequencies. However, pattern loss with increasing cycling frequency resulted not only in convergence toward the more stable in-phase patterns with the elbows and wrists but also to the anti-phase patterns (which were associated with directional compatibility of within-limb motions). Moreover, participants generally preserved their initial mode of coordination (either in-phase or anti-phase) in the proximal joints (i.e., elbows) while shifting from anti-phase to in-phase (or vice versa) with their distal joint pair (i.e., wrists). Taken together, these findings reflect the impact of two immanent types of symmetry in bimanual coordination: mirror-image and translational symmetry.  相似文献   
163.
Effects of environmental variables on performance may be mediated by individual stress states. In this study the effects of jet-aircraft engine noise and signal salience on vigilance performance and self-reported stress state were examined. One hundred and ninety-two (96 female and 96 male) participants were randomly assigned to four experimental conditions consisting of 48 participants each resulting from the factorial combination of signal salience (high and low salience signals) and noise (95 dBA intermittent aircraft noise or quiet). Performance metrics and self-reported stress state (Task Engagement, Distress, and Worry) were collected. Performance in the noise conditions was significantly better than in the quiet conditions. Performance in the high salience conditions was significantly better than the low salience conditions. Noise elevated Task Engagement and low signal salience elevated Distress. Moreover, structural equation model analyses were used to examine stress state mediation between the experimental variables and performance. These analyses indicated Engagement mediates between noise and vigilance performance.  相似文献   
164.
Two experiments are performed to investigate how luminance change contributes to prioritized selection of new over old elements. Experiment 1 demonstrates that observers prioritize items that undergo a luminance change irrespective of the direction of that change. Experiment 2 shows that foreknowledge concerning the direction of luminance change signaling the target does not allow observers to prioritize the selection of luminance onsets over offsets and vice versa. The results suggest that prioritized selection of new over old elements is mediated by a general mechanism that is sensitive to luminance change, irrespective of its direction.  相似文献   
165.
Previous research in the West has established major socio-demographic correlates of fear of crime. The interpretation of these correlates is typically based on the concept of physical or social vulnerability of individuals. These correlates are implicitly regarded as invariant to social or community contexts, reflecting universal human behavioral patterns. The present study argues that social change may alter patterns of perceptions associated with fear among socio-demographic groups, thus affecting socio-demographic correlates of fear of crime. We explore how social changes in China have created a generational gap that influences the effects of age and education on fear of crime. The study finds that, in contrast with the well-established patterns in Western communities, the young and educated exhibit a higher level of fear of crime in urban China than their counterparts. The study also finds that consistent with Western literature, females are fearful and that personal victimization experience increases the level of fear. We discuss the social and community processes that produce these interesting patterns.  相似文献   
166.

非法植入基因编辑、克隆胚胎罪设立后,学界存有部分反对观点认为本罪分则位置及实行行为的规定存在问题。基于解释论的立场,本罪保护法益为基因库安全、人性尊严以及公共卫生管理秩序,立法通过对形式法益的保护一并实现了对实质法益的保护,且公共卫生管理秩序是主要法益,故本罪在刑法分则中的体系位置无可厚非。因为“植入人或动物子宫”的行为是实现生殖系基因编辑或生殖性克隆目的的必经阶段,所以本罪实行行为的规定在技术层面上彻底断绝了被基因编辑、克隆的细胞发育成存活个体的机会,从而达到了对该犯罪行为规制的立法目的。

  相似文献   
167.
The role of intrinsic and extrinsic information feedback in learning a new bimanual coordination pattern was investigated. The pattern required continuous flexion-extension movements of the upper limbs with a 90 ° phase offset. Separate groups practiced the task under one of the following visual feedback conditions: (a) blindfolded (reduced FB group), (b) with normal vision (normal FB group), or (c) with concurrent relative motion information (enhanced FB group). All groups were subjected to three different transfer test conditions at regular intervals during practice. These tests included reduced, normal vision, and enhanced vision conditions. Experiment 1 showed that the group receiving augmented information feedback about its relative motions in real-time produced the required coordination pattern more successfully than the remaining two groups, irrespective of the transfer conditions under which performance was evaluated. Experiment 2 replicated and extended the superiority of the enhanced feedback group during acquisition and retention. Experiment 3 demonstrated that successful transfer to various transfer test conditions was not a result of test-trial effects. Overall, the data suggest that the conditions that optimized performance of the coordination pattern during acquisition also optimized transfer performance.  相似文献   
168.
Expressions involving optimal sign vectors are derived so as to yield two new applications. First, coefficient alpha for the sign-weighted composite is maximized in analogy to Lord's scale-independent solution with differential weights. Second, optimal sign vectors are used to define two groups of objects that are maximally distinct in terms of a function of the squared euclidean distances between groups. An efficient computing algorithm is described along with several examples.This research was supported in part by a research grant (DA 01070) from the U. S. Public Health Service.  相似文献   
169.
This study tested whether or not cross-cultural differences in attachment classification distributions result from systematic differences in coding practices. First, we investigated whether or not the interactive scales have been scored consistently in several different cross-cultural samples. Second, the Richters, Waters, and Vaughn (1988) functions were applied to address the question of whether or not attachment classifications were consistently based upon the same pattern of interactive behaviors. Third, cross-cultural coding differences were described from a multivariate perspective. Data sets from seven investigators in six countries were available for analysis. Analyses on this “multinational data set” revealed that except for distance interaction, the interactive scales in the two reunion episodes were scored in accordance with the original coding rules. Furthermore, a good to reasonable agreement appeared to exist between the original classifications and those computed by the functions, except for infants older than 20 months of age. The multivariate principal component analysis showed that classification groups across cultures were more alike than cultures across classification groups. Our data showed, therefore, that attachment classifications have been consistently coded across cultures.  相似文献   
170.
We investigated changes in bias (preference for one response alternative) in signal detection when relative reinforcer frequency for correct responses varied across sessions. In Experiment 1, 4 rats responded in a two-stimulus, two-response identification procedure employing temporal stimuli (short vs. long houselight presentations). Relative reinforcer frequency varied according to a 31-step pseudorandom binary sequence and stimulus duration difference varied over two values across conditions. In Experiment 2, 3 rats responded in a five-stimulus, two-response classification procedure employing temporal stimuli. Relative reinforcer frequency was varied according to a 36-step pseudorandom ternary sequence. Results of both experiments were analyzed according to a behavioral model of detection. The model was extended to incorporate the effects of current and previous session reinforcer frequency ratios on current-session performance. Similar to findings with concurrent schedules, effects on bias of relative reinforcer frequency were highest for the current session. However, carryover from reinforcer ratios of previous sessions was evident. Generally, the results indicate that bias can come under control of frequent changes in relative reinforcer frequency in both identification and classification procedures.  相似文献   
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