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31.
Won Seok Chang Sun-Ah Song Yun Hwangbo Jae-Hyun Kim Hak-Joo Lee 《Philosophical Magazine Letters》2013,93(8):391-398
Carbon nanotubes have been intensively studied owing to their great potential in nanoelectronics and nanomechanical devices. Recently, experimental results have shown that single-walled carbon nanotubes (SWCNTs) change their electronic properties when subjected to strain. In this study, the electromechanical characteristics of SWCNT networks were investigated for the application of printable strain sensors on flexible substrates. SWCNT films were formed on plastic substrates of poly(ethylene terephthalate) using a spray process. In this manner, we were able to control the transparency and obtain uniform electrical properties of the films. The films are isotropic on account of the random orientation of bundles of SWCNTs. Experimental results showed a nearly linear change in the resistance across a film when it was subjected to tensile strain, even in the inelastic range of the flexible substrate. The results demonstrate the potential use of SWCNT films for highly sensitive printable strain sensors on a macroscale. 相似文献
32.
心理负荷的评估正经历着从传统工效学向神经人因学的变革.EEG、ERPs、fMRI、fNIRS和TCD等神经科学研究技术为这场变革提供了有力的工具.研究发现:在单任务情境下,随着操作者心理负荷的增加,脑电α波活动减弱,θ波活动增强,并且前额皮层血流、左侧额下回血液氧合血红蛋白浓度变化均增加,大脑动脉血流速度也增快;在双任务情境下,随着操作者主任务心理负荷的增加,次任务的N1、新异P3和P3b等ERPs成分波幅降低.依据这些研究成果,学者们利用人工神经网络、支持向量机等模式分类算法实现了对心理负荷的实时在线评估.但是,各种研究技术在敏感性、诊断力、主任务干扰、实施需求、可接受性和信度等方面各有优势与不足.在未来研究中,要注意促进相关技术的融合、提高其可接受性,并充分利用模式识别算法提高其诊断力和敏感性. 相似文献
33.
选取大学本科生33名,采用情绪启动范式与再认范式相结合,要求被试依次完成情绪词识记、目标面孔性别判断及情绪词再认任务,探讨保存于工作记忆中的情绪性刺激对面孔性别判断任务的影响。结果显示:(1)在中性和恐惧情绪启动刺激条件下,被试对目标面孔性别判断的反应时要显著长于悲伤条件。(2)在愉悦情绪启动词条件下,线索提示有效性差异显著;在无效线索提示条件下,启动刺激的不同情绪效价差异显著。(3)对情绪面孔性别与被试性别一致性/非一致性两种条件下反应时对比发现,男、女被试在情绪面孔性别判断任务中均表现出异性相吸效应。综上所述,保存在工作记忆中情绪刺激会对面孔性别的识别产生自上而下的影响。 相似文献
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36.
随着移植免疫学研究的不断深入发展,诱导免疫耐受克服移植排斥反应已成为器官移植的主要研究目标。Starzl提出“双向移植排斥理论”并阐述临床使用免疫抑制药物下移植排斥反应的特点,突破了原有单向移植排斥理论的框架。“双向移植排斥理论”及理论内存在的问题给予我们众多有益的思考,在移植免疫学研究中,只有坚持用系统原则动态的看待事物间的联系与矛盾,进行科学实践,才能获得正确的理论,从而进一步推动移植免疫学的发展。 相似文献
37.
Seyed Ebrahim Mousavi Wah Yun Low Aili Hanim Hashim 《Journal of child and family studies》2016,25(7):2102-2110
A growing body of literature links particular parenting practices with negative child outcomes including greater anxiety symptoms among western societies. However, the effects of cultural differences on such linkages have not been adequately addressed in the anxiety literature. This study therefore aimed to examine the relationship between perceived parenting style and anxiety among Malay, Chinese, Indian, Arab and European/American (Caucasian) origins adolescents and the possible cultural group influences on this relationship was studied. Using multiple cluster sampling, a total of 227 students (122 boys and 105 girls) aged 13–18 years was selected. They completed questionnaires measuring parental rearing behaviors (EMBU-C) and anxiety symptoms scale (SCAS). Results indicated that in comparison to the European/American; Asian samples reported greater anxiety symptoms on all subscales of anxiety. Parental rejection, anxious rearing and control/over protection were correlated to higher anxiety independent of cultural group but these associations were stronger for Caucasians. Parenting styles as predictor of anxiety were found to be cross culturally different. Although European/American adolescents rated their parents as least over controlling, it was significant predictor of anxiety. This study provides evidence for the notion that relationship between parenting factors and anxiety were different across cultural contexts. 相似文献
38.
人脑对反馈的评估依赖于其所处背景。但是只能依赖整体背景(整个组块的结果范围), 还是可以依赖局部背景(单个试次的结果范围)进行评估, 目前并不清楚。本研究通过获益/损失线索操纵所在试次的反馈背景, 探讨反馈评估仅依赖整体背景, 还是可延伸到局部水平。25名被试参与实验。结果发现, 背景试次间变化时, 在获益背景下, ¥0 (负反馈)比+ ¥4 (正反馈)引发更负的FRN (feedback-related negativity); 在损失背景下, - ¥4 (负反馈)比¥0 (正反馈)引发更负的FRN。这一结果说明反馈评估以某线索背景中可能的结果为参考对象, FRN的背景依赖可以延伸到局部水平。结合前人研究, 推测任务类型和反馈真实性会调节背景依赖水平。在含真实反馈的主动性任务中, FRN的背景依赖效应可延伸至局部水平。 相似文献
39.
婴儿面孔图式效应是促进早期亲子关系形成的一种先天本能反应, 该效应一直被认为主要是受婴儿面孔结构的影响。但近年来表情对该效应的影响开始得到关注, 在以成人面孔为基线的条件下, 婴儿面孔图式效应量会因表情不同而有所变化, 表现出中性婴儿面孔图式效应最强的现象。鉴于目前对该现象的成因及其神经机制知之甚少, 所以本项目拟先建立一套婴儿与成人同面孔多表情图片系统; 然后以此为基础, 分别考察面孔表情不确定性是否会调节成人对不同表情婴儿面孔的偏好和注意偏向, 并探究其相应神经机制, 促进养育脑研究在我国的开展。 相似文献
40.
Miwa Yasui Kathleen J. Pottick Yun Chen 《Clinical child and family psychology review》2017,20(3):250-332
Despite the central role culture plays in racial and ethnic disparities in mental health among ethnic minority and immigrant children and families, existing measures of engagement in mental health services have failed to integrate culturally specific factors that shape these families’ engagement with mental health services. To illustrate this gap, the authors systematically review 119 existing instruments that measure the multi-dimensional and developmental process of engagement for ethnic minority and immigrant children and families. The review is anchored in a new integrated conceptualization of engagement, the culturally infused engagement model. The review assesses culturally relevant cognitive, attitudinal, and behavioral mechanisms of engagement from the stages of problem recognition and help seeking to treatment participation that can help illuminate the gaps. Existing measures examined four central domains pertinent to the process of engagement for ethnic minority and immigrant children and families: (a) expressions of mental distress and illness, (b) causal explanations of mental distress and illness, (c) beliefs about mental distress and illness, and (d) beliefs and experiences of seeking help. The findings highlight the variety of tools that are used to measure behavioral and attitudinal dimensions of engagement, showing the limitations of their application for ethnic minority and immigrant children and families. The review proposes directions for promising research methodologies to help intervention scientists and clinicians improve engagement and service delivery and reduce disparities among ethnic minority and immigrant children and families at large, and recommends practical applications for training, program planning, and policymaking. 相似文献