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991.
The diffusion kinetics in a concentrated fcc alloy are described by means of divacancies. The model chosen is the random alloy model with bound divacancies. We show that for the fcc structure the Manning formalism developed originally for monovacancies can be used intact to describe diffusion via divacancies. Monte Carlo simulation results for both tracer and collective correlation factors are in good agreement with the results of the formalism for a wide range of the component atom exchange frequencies with the divacancy except for the slower-moving component. 相似文献
992.
M.E. Manley R.J. McQueeney J.L. Robertson B. Fultz D.A. Neumann 《Philosophical Magazine Letters》2013,93(8):591-596
Time-of-flight inelastic neutron scattering spectra were measured on cerium metal at temperatures near the fcc (gamma)-to-bcc (delta) transition temperature. Phonon density-of-states (DOS) curves were extracted from data acquired over a wide range of momentum transfers. A large softening of the phonon DOS was found in going from gamma-cerium to delta-cerium, and this accounts for an increase in vibrational entropy of (0.71 +/- 0.05)k B/atom. To be consistent with the latent heat of the gamma-delta transition, this increase in vibrational entropy must be accompanied by a large decrease in electronic entropy. The results not only confirm the recent discovery of a significant electronic contribution to the gamma-delta transition but also suggest that it may be twice that previously reported. 相似文献
993.
994.
Genetic and environmental correlation matrices among 7 personality scales were estimated, using samples of adult and young adult twins from Australia (2081 and 1178 pairs, respectively). A general factor of personality and two supplemental factors were obtained in each. The supplemental factors were tentatively identified as Social conformity and Other-dependence. Factors from the genetic and environmental correlations replicated well across samples, and they were similar in both the genetic and environmental covariation. It was concluded that the structure of personality is inherent in the evolved phenotype, and is not the immediate consequence of either genetic or environmental organizing factors. 相似文献
995.
ASHOK K. GANGADEAN 《World Futures: Journal of General Evolution》2013,69(1-2):56-74
This article suggests that we are in the midst of a profound dimensional shift in our rational capacity to process reality, and seeks to articulate the implications of this evolutionary shift to global reason for our scientific enterprise. As we enter the 21st century it is unmistakably clear that we are in the midst of an unprecedented shift in the human condition—a global renaissance that affects every aspect of our cultural lives, our self-understanding, and, of course, our rational enterprise. This evolutionary transformation, when seen through the expanded global lens, has been emerging through the ages on a global scale. In this brief reflection I suggest that this advance in our technology of mind is of an order of magnitude that is so radical and comprehensive that the very concept of a person, of what it means to be human, of our encounter with Reality and all our hermeneutical arts, including the sciences, are likewise taken to a higher global dimension. I suggest that the diverse voices included in this special edition are best situated in the context of this global awakening of reason, scientific knowing, and the holistic worldview. 相似文献
996.
There are very significant conceptual links between theories of social macroevolution and theories of the World System development. It is shown that the growth of the World System complexity and integrity can be traced through a system of phase transitions of macroevolution. The first set of phase transition is connected with the agrarian, industrial, and information-scientific revolutions (that are interpreted as changes of “production principles”). The second set consists of phase transitions within one production principle. These phase transitions are analyzed on the basis of the World System urbanization dynamics, but they can be traced with respect to the other (cultural, economic, technological, demographic, political, etc.) dimensions of the World System development. 相似文献
997.
998.
Humans are extremely good at detecting anomalies in sensory input. For example, while listening to a piece of Western-style music, an anomalous key change or an out-of-key pitch is readily apparent, even to the non-musician. In this paper we investigate differences between musical experts and non-experts during musical anomaly detection. Specifically, we analyzed the electroencephalograms (EEG) of five expert cello players and five non-musicians while they listened to excerpts of J.S. Bach’s Prelude from Cello Suite No. 1. All subjects were familiar with the piece, though experts also had extensive experience playing the piece. Subjects were told that anomalous musical events (AMEs) could occur at random within the excerpts of the piece and were told to report the number of AMEs after each excerpt. Furthermore, subjects were instructed to remain still while listening to the excerpts and their lack of movement was verified via visual and EEG monitoring. Experts had significantly better behavioral performance (i.e. correctly reporting AME counts) than non-experts, though both groups had mean accuracies greater than 80%. These group differences were also reflected in the EEG correlates of key-change detection post-stimulus, with experts showing more significant, greater magnitude, longer periods of, and earlier peaks in condition-discriminating EEG activity than novices. Using the timing of the maximum discriminating neural correlates, we performed source reconstruction and compared significant differences between cellists and non-musicians. We found significant differences that included a slightly right lateralized motor and frontal source distribution. The right lateralized motor activation is consistent with the cortical representation of the left hand – i.e. the hand a cellist would use, while playing, to generate the anomalous key-changes. In general, these results suggest that sensory anomalies detected by experts may in fact be partially a result of an embodied cognition, with a model of the action for generating the anomaly playing a role in its detection. 相似文献
999.
返回抑制(IOR)是指注意过程中个体对已搜索过的位置进行抑制, 从而在随后该位置上出现目标时发生注意重新定向或反应变慢的过程。本研究使用ERPs技术, 采用线索-靶子范式, 考察了情绪目标辨别任务中IOR的发生过程及二者的神经机制。结果发现, 与无效线索相比, 有效线索下的P1波幅更小, N1波幅更大, 正性、负性面孔N170的波幅比中性面孔大。表明当要求被试做情绪辨别任务时, IOR与对情绪信息的反应之间发生了分离, 表现出情绪加工的优先。这说明IOR和情绪偏向是发生在两种不同神经通路上的适应机制, 也为进一步探究注意与情绪的关系问题提供了来自神经电生理学的证据。 相似文献
1000.
Current research distinguishes between self, directive and social function of autobiographical memories (AMs). To date, only few studies have investigated these functions across adulthood. The comparison of different age groups requires that the functions of AM are measured in the same way across groups (measurement invariance, MI). Additionally to the average use of AM, the factor variances and factor covariances among the three functions were examined across adulthood. In the present study, 1290 adults (aged between 17 and 93 years) completed the Thinking about Life Experiences Questionnaire (TALE), which measures the overall use of AMs for self, directive and social purposes. The sample was divided into five age groups and partial strong MI was established using multigroup confirmatory factor analysis. The results showed an increase in the factor associations as well as a decrease in the factor mean levels of all three functions across age groups. Both findings could be adequately described by linear functions of age. The factor variances were on most parts equal across age groups. These results strengthen the assumption that—from a lifespan developmental perspective—the use of AM may be aligned with relatively normative developmental tasks in a given society. 相似文献