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51.
Visually perceiving an action may activate corresponding motor programs. This automatic motor activation can occur both for higher level (i.e., the goal of an action) and for lower level (i.e., the specific effector with which it is executed) aspects of an action. The authors used a tool-use action paradigm to experimentally dissociate priming effects for observing the target, the movement, or the target-to-movement mapping of a tool-use action. In 3 experiments, participants took turns in acting, observing the tool-use action of another person in trial n-1, and executing an action in trial n. Trial transitions from n-1 to n were manipulated in 4 conditions with (a) mapping repeated and movement and target changed, (b) target repeated and movement and mapping changed, (c) movement repeated and target and mapping changed, or (d) all components repeated. Results indicate priming effects for repeating the target-to-movement mapping (i.e., the action rule) of a tool-use action and suggest that a rather abstract action schema is activated during action observation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
R.A. Forrest 《Fusion Engineering and Design》2006,81(18):2143-2156
Existing neutron cross section libraries such as EAF-2003 contain a large number of reactions. Of these only a small proportion are significant in the production of the nuclides that dominate activation quantities such as activity or γ-dose rate at various decay times. These reactions were identified in a recent extensive set of calculations on all the elements and reported in the ‘Activation Handbook’. These 1340 reactions are considered here and the set of reactions with no differential or integral data are listed and prioritised. A set of 339 reactions with very limited possibility of measurement are given; these require further study by theoretical calculations. A set of 100 reactions with either discrepant or no data, that might be measurable are listed and are recommended to be the subject of future experimental work. 相似文献
53.
T. LUNDGREN E. U. ENGSTR
M R. LEVI-SETTI A. LINDE J. G. NORN 《Journal of microscopy》1994,173(2):149-154
The incorporation into rat incisor dentin of two calcium isotopes, the stable 44Ca and the radioactive 45Ca, was studied using secondary ion mass spectrometry (SIMS) stepscanning and imaging, and autoradiography, respectively. The results demonstrated a time-dependent incorporation of the calcium isotopes into the mineral phase of dentin. With the SIMS step-scanning, detecting 44Ca, the ion yield was high in the odontoblasts 2 min after intravenous injection. After 10 min a marked increase in signal intensity was found at the dentin mineralization front. This result was consistent with those obtained by 45Ca autoradiography; a peak of incorporation occurred 10 min after injection of the isotope. Likewise, localization of 44Ca to the mineralization front could be demonstrated 10 min after injection by SIMS imaging. In images obtained at earlier intervals, no such increase in ion yield could be detected. The results show that the nonradioactive, stable isotope 44Ca can be used as a marker for biomineralization in a similar way to radioactive 45Ca. 相似文献
54.
布尔函数的对偶性和线性点 总被引:5,自引:1,他引:4
本文主要讨论了部分自对偶和部分反自对偶函数、部分线性函数以及具有线性点的函数的性质。 相似文献
55.
钛酸酯催化环氧树脂固化动力学研究 总被引:6,自引:2,他引:4
用FTIR“原位”技术,研究了钛酸酯(Tc-114)偶联剂对环氧E-44和二氨基二苯基甲烷(DDM)固化反应的催化作用,得出固化程度与时间的关系曲线。又根据DSC曲线,分别算出加有Tc-114和不加Tc-114的两个固化体系的反应表观活化能和反应级数。结果表明,Tc-114的存在使环氧固化反应活化能降低,催化作用明显。 相似文献
56.
This article identifies the key issues involved in the debate about affirmative action. The June 2003 Supreme Court decisions allowing consideration of race to ensure that there is a "critical mass" of African American, Latino/Latina, and Native American applicants to higher education are addressed. Social psychologists have identified key myths and provided clarifications about the need for and consequences of strategies used to promote equal opportunity for persons of color and women. A brief history of affirmative action and of the problems it was designed to solve is provided. The accomplishments, benefits, and compelling interest of diversity and affirmative action are described, as well as the concerns and counterpoints. The lack of a substantial applicant pool in psychology hinders progress toward diversity. Alternative strategies for remedying this lack beyond affirmative admissions policies in psychology are briefly discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
在压水堆核电站应急计划和应急响应中,堆底熔穿事故占有重要位置。本文用法国核电厂事故源项S3(对应于堆底熔穿事故)计算了在典型气象条件下的场外放射学的后果,根据一般防护决策原则和我国颁布的干预水平,提出了保护公众的应急防护措施的建议。 相似文献
58.
用反应谱理论对三峡左厂房坝导墙3种典型设计断面型式进行了抗震计算分析比较,得出了其自振特性及地震动位移、动应力响应。对选定的设计断面型式Ⅲ进行了抗拉应力强度安全性评价。 相似文献
59.
We present a methodology for compiler synthesis based on Mosses-Watt's action semantics. Each action in action semantics notation is assigned specific “analysis functions”, such as a typing function and a binding-time function. When a language is given an action semantics, the typing and binding-time functions for the individual actions compose into typing and binding-time analyses for the language; these are implemented as the type checker and static semantics processor, respectively, in the synthesized compiler. Other analyses can be similarly formalized and implemented. We show a sample language semantics and its synthesized compiler, and we describe the compiler synthesizer that we have developed. 相似文献
60.
详细介绍了在改进红外焊缝检测仪的过程中实时信号的一种抗干扰方法--自相关方法。重点离自相关方法的数学模型,软件框图及设计思想,并给出了实验结果。 相似文献