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151.
Abstract This Letter presents a solution of the problem of the real temperature of nanoparticles under conditions of electron microscope beam irradiation. It is shown that the average temperature of the nanoparticles (NPs) may increase to several hundred degrees depending on contact conditions with the substrate, the intensity of the beam and the size of the NPs. The temperature increases with NP size a according to the dependence: T α a2 for sufficiently small particles. 相似文献
152.
This letter presents the results of internal-friction measurements of Co 70 Fe 5 Si 15 B10 metallic glass at temperatures 400K h T h 700K and frequencies 0.01 Hz h f h 0.05Hz. It is shown that Maxwellian viscoelastic damping is predominant in this case. The nature of this damping is determined by irreversible structural relaxation. The kinetic relaxation law is derived. 相似文献
153.
Yu.B. Bolkhovityanov A.S. Deryabin A.K. Gutakovskii L.V. Sokolov 《Philosophical Magazine Letters》2013,93(7):458-464
Edge misfit dislocations (MDs) formed as result of reactions between 60° glissile threading dislocations and 60° MDs lying on an intersecting glide plane were found in strained GeSi-on-Si(001) and Ge-on-InGaAs/GaAs films. It was demonstrated that dislocations penetrating from the InGaAs buffer layer to the strained Ge film can provoke formation of not only 60° MDs, but also edge MDs on the interface even at minor mismatch of the lattice parameters of the film and the InGaAs/GaAs virtual substrate. 相似文献
154.
Empirical studies have validated that basic needs satisfaction supported by video game play predicts motivation and engagement outcomes. However, few studies specifically manipulated game features for each of the three basic needs specified in the self-determination theory (SDT) to examine how the game features impact players' need satisfaction and game experience. The current study employed an in-house developed exergame and manipulated the game features in a 2 (autonomy-supportive game features: on vs. off) × 2 (competence-supportive game features: on vs. off) experiment to predict need satisfaction, game enjoyment, motivation for future play, effort for gameplay, self-efficacy for exercise using the game, likelihood of game recommendation, and game rating. The manipulated game features led to the corresponding need satisfaction. Manipulated autonomy-supportive and competence-supportive game features had main effects on most motivation and engagement outcomes. Need satisfaction of autonomy and need satisfaction of competence were both found to be mediators for the relationships between the game features and the motivation and engagement outcomes. The findings add evidence to support the underlying mechanism postulated by SDT for media enjoyment and motivation as well as the emerging entertainment research conceptualizing enjoyment as need satisfaction. The findings also have practical implications for intervention effort that intends to capitalize the motivational pull of video games. 相似文献
155.
Linda B. Smith Chen Yu Hanako Yoshida Caitlin M. Fausey 《Journal of cognition and development》2013,14(3):407-419
Head-mounted video cameras (with and without an eye camera to track gaze direction) are being increasingly used to study infants’ and young children's visual environments and provide new and often unexpected insights about the visual world from a child's point of view. The challenge in using head cameras is principally conceptual and concerns the match between what these cameras measure and the research question. Head cameras record the scene in front of faces and thus answer questions about those head-centered scenes. In this “Tools of the Trade” article, we consider the unique contributions provided by head-centered video, the limitations and open questions that remain for head-camera methods, and the practical issues of placing head cameras on infants and analyzing the generated video. 相似文献
156.
157.
Cardiomyopathy is a genetically and clinically heterogeneous, life threatening disease which affects people of all ages. Recent guidelines provide recommendations for cardiac screening and genetic testing in at-risk relatives, but the uptake and impact of these measures in the United States is unknown. This is a single institution retrospective study that characterizes the uptake of cardiac screening and genetic testing for relatives of a cohort of 57 probands with hypertrophic (HCM) and dilated cardiomyopathy (DCM) who underwent both clinical evaluation and genetic testing. Cardiac screening was indicated for 302 relatives. One hundred and seventy-three (57 %) completed cardiac screening. Forty of the 57 probands were mutation positive and genetic testing was indicated for 213 relatives. Eighty-four (39 %) completed genetic testing. The uptake of cardiac surveillance was greater than the uptake of genetic testing (p?<?0.0001) among relatives of mutation positive probands. Within the group of at-risk, asymptomatic relatives of probands, cardiac screening and genetic testing were positive in 25 % and 40 % of cases, respectively. These data demonstrate the important role and utility of cascade cardiac screening and genetic testing in the care of patients and families with HCM or DCM. The approach to cardiac screening and genetic testing should be family-specific and requires expertise in the genetics of cardiomyopathy. 相似文献
158.
With the development of visual prostheses research from the engineering phase to clinical trials, volunteer recruitment for the early visual prosthesis trials needs to be carefully considered. In this article, we mainly discuss several issues related to volunteer recruitment that had posed serious challenges to the visual prosthesis trials, such as low rates of participants, high expectations and underlying motivations to participate in the visual prosthesis trials as well as the importance of informed consent. When recruiting volunteers for visual prosthesis implants, it is critical that the visual prosthesis researchers should not only take into account the patient’s expectations and motivations, but also make the patients fully aware of the possible benefits and risks involved with their participation, and help patients establish realistic expectations for the early phase of visual prosthesis implantation. Based on these considerations to the challenges, eligible volunteers may be recruited in the preliminary stages of visual prosthesis trials. 相似文献
159.
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
160.
采取整群抽样的方法,对成都及重庆两地591名流动儿童和272名城市儿童进行问卷调查,考察流动儿童疏离感的特点及其与应对方式和学校态度的关系。结果发现:(1)流动儿童疏离感各维度显著高于城市儿童;流动初中生的疏离感显著高于流动小学生,且男生的疏离感显著高于女生;(2)流动儿童疏离感的三个维度之间存在显著差异,其中社会疏离感最高,其次是环境疏离感,人际疏离感最低;(3)流动儿童疏离感对学校喜欢有显著的负向影响,而对学校回避有显著的正向影响;应对方式在流动儿童疏离感对学校态度的影响中起着部分中介作用。 相似文献