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181.
Multiple types of victimization or poly‐victimization (PV) can occur simultaneously during childhood, resulting in outcomes that are detrimental and difficult to reverse. Very few studies have focused on PV in Chinese adolescents. The present study is based on information collected from a stratified cluster sample of 1,561 females and 1,594 males aged 12–18 years living in Shandong Province, China. A self‐administered questionnaire was used to assess background information, the Juvenile Victimization Questionnaire was used to measure the extent of victimization and PV, the Screen for Child Anxiety Related Emotional Disorders was used to measure anxiety levels, and a Depression Self‐rating Scale for Children was used to ascertain depression. A majority of the study sample (66.2%) had experienced at least one form of victimization over the past year. Prevalence of PV was 16.9%, and was significantly higher among males (21.1%) than females (12.5%). Younger ages, one‐child families, and lower socioeconomic status were positively associated with PV. Logistic regression analysis indicated that smoking, alcohol consumption, exposure to pornography, and anxiety‐ and depression‐like symptoms were risk factors of PV. Results of this study highlight the need for further exploration of factors related to the PV of Chinese adolescents.  相似文献   
182.
Past researches showed that empathy for pain not only triggers a resonance mechanism between other and self, but also is modulated by contextual factors. Using functional magnetic resonance imaging, the present study demonstrated that short-term media violence exposure reduced both pain ratings and also the activation of anterior insula and anterior mid-cingulate cortex to other’s pain. Thus, violence exposure modulated empathic responses to other’s pain based on a physiological desensitization.  相似文献   
183.
探讨并比较真实火灾和模拟火灾情境下小鼠是否采用直觉性逃生决策。研究包括一个预备训练和两个主实验。预备训练的目的:首先训练小鼠获得有关迷宫路线及出口的经验,然后再经过遗忘处理使它们遗忘相关经验。两个主实验均采用3(情境:真实火灾,模拟火灾,普通情境)×2(记忆:遗忘前和遗忘后)混合实验设计,因变量均为逃生决策。实验组被试为72只经过训练的小鼠,控制组为24只未经过训练的小鼠。通过考察小鼠在不同情境和不同记忆条件下的逃生时间和对逃生出口的选择探测并比较真实火灾和模拟火灾情境下小鼠的逃生决策差异。主要结果:(1)实验组在真实火灾情境下的逃生时间无论遗忘前后都明显比模拟火灾情境下短;(2)实验组在真实火灾和模拟火灾情境下的逃生时间都明显比控制组短;(3)当熟悉和陌生出口均开启同时熟悉出口处有烟雾条件下,真实火灾组在遗忘前后均倾向于选择熟悉出口逃生,其他两组则倾向于选择陌生出口离开。结论:真实火灾和模拟火灾情境下小鼠的逃生决策存在明显差异:真实火灾情境下受过训练的小鼠倾向于直觉性逃生决策;模拟火灾情境下受过训练的小鼠不倾向于直觉性逃生决策。  相似文献   
184.
ABSTRACT

The interaction between interfacial dislocations and γ/γ′ interface is critical to the high temperature creep properties of single crystal superalloys. However, only a few studies have paid attention to the detailed structure such as local interfacial morphologies and the elemental distribution around interfacial dislocations. In this paper, the interfacial protrusions and related dislocations in a single crystal superalloy after creep at high temperature – low stress have been investigated in detail. It is found that the morphology and size of the interfacial protrusions remain almost the same during the early and middle stages of high temperature creep, which indicates a local equilibrium at the interfacial protrusions. Steps at different height are formed at the γ/γ′ interface at the initial stage of high temperature creep since dislocations could move along the γ/γ′ interface, which indicates that dislocation motion at different creep stage may affect the morphology of γ/γ′ interface.  相似文献   
185.

Electrical resistivity, thermoelectric power, magnetic susceptibility and calorimetric measurements were carried out on a single crystal of CuO. In addition the two known antiferromagnetic transitions between 210K and 230K, a new phase transition around 160K was found in CuO. The experimental results show that this new transition is related to changes in the electronic state of CuO.  相似文献   
186.

The position of Dy in the unit cell of Bi2Sr2CaCu2Oy has been determined by a real-space method. This is compared with the reciprocal-space atom location by channelling-enhanced microanalysis (ALCHEMI) method.  相似文献   
187.

Contact problems between two solids are essential to interpret the loading-unloading behaviour in indentation tests. Using linear elastic theory, a general relationship between the normal stress and the surface deformation for elastic contact of two solids was derived, in which the normal stress is a function of the mean curvature of the undeformed surface.  相似文献   
188.
This paper examines whether emotional message content alters the effects of structural complexity and information density on available resources, measured by secondary task reaction times (STRTs), and message encoding, measured by audio recognition. In addition, hypotheses relating motivational activation and resource availability based on the motivational activation concepts of positivity offset (greater appetitive activation in a neutral environment) and negativity bias (faster aversive activation) influence are tested. Results replicate previous research supporting the contention that STRTs measure available resources. In addition, they show that the basic pattern of STRTs and recognition as a function of allocated and required resources is relatively consistent regardless of emotional content of the message. Emotion appears to function as a constant, increasing both resource allocation and resources required. Finally, these data provide some initial support for predicted relationships between motivational activation and resource allocation based on the constructs of positivity offset and negativity bias.  相似文献   
189.
The aim of the present study was to investigate the time course of the positive advantage in the expression classification of faces by recording event-related potentials (ERPs). Although neutral faces were classified more quickly than either happy or sad faces, a significant positive classification advantage (PCA)—that is, faster classification for happy than for sad faces—was found. For ERP data, as compared with sad faces, happy faces elicited a smaller N170 and a larger posterior N2 component. The P3 was modulated by facial expressions with higher amplitudes and shorter latencies for both happy and neutral stimuli than for sad stimuli, and the reaction times were significantly correlated with the amplitude and latency of the P3. Overall, these data showed robust PCA in expression classification, starting when the stimulus has been recognized as a face revealed by the N170 component.  相似文献   
190.
Blinks are related to several emotional states, and the present report describes a simple, reliable way to measure blinks from the video stream of an eye obtained during eyetracking, where the source of the eye video is a video camera attached to a head-mounted eyetracker. Computer vision techniques are employed to determine the moments that a blink starts and ends, for the purpose of calculating blink frequency and duration. The video is first processed to show blocks of eyelid and pupil movements, and is then analyzed for blink starts and ends. The moment of a blink start is reported when the eyelid starts to move quickly, exceeding a predetermined threshold. The end of a blink arises when the pupil size increases by less than a separate threshold. We observed several different blink patterns from different subjects, and our algorithm was designed to work for all of these patterns. We evaluated our algorithm by manually measuring the true blinks of five different subjects while they were eyetracked. To test the sensitivity and specificity of the algorithm, we employed a series of threshold values to plot the receiver operating characteristic curves. Using the best thresholds, we achieved excellent sensitivity (>90 %) and specificity (>99 %) over the five subjects. Potential applications of this research include real-time, nonintrusive, continuous and automated measurements of mental workload and other emotional states related to blink rates and durations.  相似文献   
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