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101.
A. Letoublon T. Ishimasa M. De Boissieu M. Boudard B. Hennion M. Mori 《Philosophical Magazine Letters》2013,93(4):205-213
The stability of the F2-(Al-Pd-Mn) phase has been studied by in-situ neutron diffraction on a single quasicrystal with composition Al69.8Pd21.4Mn8.8. We find that the F2 phase is not stable and corresponds to a transient state in the process of the transformation of the icosahedral phase to the F2M phase. The icosahedral-to-F2Mphase transition occurs at around 715oC. In the F2 phase a large amount of diffuse scattering is located close to the icosahedral Bragg reflection in place of the S 1 superstructure reflections characteristic of the F2m phase. 相似文献
102.
H. Cabrera J.J. Suárez-Vargas A. López H. Núñez G. Carvalho G. Coceano 《Philosophical Magazine Letters》2013,93(11):655-663
We report an experimental determination of trapping efficiency of optical fields acting on spherical particles diluted in viscous fluids. This parameter was derived from experimentally calculated trap stiffness for micron-sized silica beads with particle radii of 1.5 and 4.8 microns, respectively. In order to obtain the trap stiffness, we used the equipartition theorem, and introduced an experimental procedure to calibrate the optical tweezers set-up. The method consists of the calculation of the trapping efficiency by using the curves of the trap stiffness vs. the incident power. Using this approach we measured the efficiency for different values of displacements of the beads in the optical trap, and compared these results with numerical and theoretical calculations reported in the literature, and an excellent agreement was found. We have shown that the ratio of efficiencies is very close to the ratio of the particle radii. 相似文献
103.
Raymond Bradley 《World Futures: Journal of General Evolution》2013,69(2-3):175-211
In drawing on my own research and collaborative work with Karl Pribram, I show that love (affective attachment) and power (social control) play a central role in psychosocial evolution. When these relations are coupled in a self-regulating system of cooperative interactions, brain growth is stimulated, mind and agency develop, and stable forms of collective social organization are generated. Focusing on the endogenous dynamics of social collectives, the article is organized in four parts. (A "social collective" is defined as a durable arrangement of relations among two or more individuals that is distinguished by shared membership and collaboration in relation to a common function or goal.) Part I summarizes evidence from developmental neuropsychology and social science to show that stable psychosocial organization, across the human life span, is associated with social interaction organized along two dimensions. One dimension involves love, positive affective attachment, and the second involves power, social regulation of the aroused affective energy. Part II draws on Piaget's theory of cooperation and Bradley and Pribrams' theory of communication to describe how mind and agency are generated, and how stable organization is produced, respectively, from the relations involved in the arousal and regulation of affective energy. Combining elements of the two theories, Part III presents a sketch of a holographic model of collective organization in which goal-directed behavior is generated by a feed-forward process involving imaging and information processing of interaction along the two dimensions. Part IV shows how the model accounts for the emergence of human agency within the context of a more general evolutionary theory, such as Laszlo's. The article concludes with a discussion of my approach for building a "fully human theory of evolution." 相似文献
104.
Khwaja Sarmad 《World Futures: Journal of General Evolution》2013,69(1-2):53-99
Any changing system both develops and evolves (individuates). The evolution of the biosphere must therefore be taken in context of the development of the earth, which appears to have followed typical developmental rules of dissipative structures. Two different perspectives are possible on dissipative structures—the classical externalist perspective, which views open systems as becoming progressively negentropic, and the newer, internalist perspective, which views them from within as becoming increasingly disorderly. A history of the universe can be traced, alternately stressing the one and the other perspective, which can form the basic structure of a modern, science‐based creation myth. 相似文献
105.
James M. Kerns 《Theology & Science》2013,11(3):251-288
AbstractGaps are a reality in neuroscience, but are also a rich metaphor toward understanding/dialog in other life aspects with points of separation. Starting with the transportation gap in London, we examine other gaps that may be illusory, along a spectrum, more serious/complex and almost defying resolution. By attending to these gaps, we can then better decide when and where dialog can occur with an appropriate action. Such collaboration, especially between neuroscience and theology, reveals the utility of a model depicting interaction/wholeness of the human brain/mind/spirit in relationship to consciousness and with social implications for better health in a gap-filled society. 相似文献
106.
Robert Baker 《The American journal of bioethics : AJOB》2013,13(2):39-41
Detection of deception and confirmation of truth telling with conventional polygraphy raised a host of technical and ethical issues. Recently, newer methods of recording electromagnetic signals from the brain show promise in permitting the detection of deception or truth telling. Some are even being promoted as more accurate than conventional polygraphy. While the new technologies raise issues of personal privacy, acceptable forensic application, and other social issues, the focus of this paper is the technical limitations of the developing technology. Those limitations include the measurement validity of the new technologies, which remains largely unknown. Another set of questions pertains to the psychological paradigms used to model or constrain the target behavior. Finally, there is little standardization in the field, and the vulnerability of the techniques to countermeasures is unknown. Premature application of these technologies outside of research settings should be resisted, and the social conversation about the appropriate parameters of its civil, forensic, and security use should begin. 相似文献
107.
Denisa Bártková Miroslav Šmíd Bohuslav Mašek Jiří Svoboda 《Philosophical Magazine Letters》2017,97(10):379-385
A nearly abrupt coarsening of grains is observed in a newly developed Fe–Al–O ultra-fine-grained nanocomposite with a significant volume fraction (4%) of alumina nano-precipitates. The microstructure of the alloy was analysed in different states (as-received and annealed) by means of scanning electron microscopy, transmission electron microscopy (TEM) and hardness. The initial grain size 150–200 nm increases up to 50 μm during annealing 1000 °C/8 h and thereafter demonstrates saturation. A linear correlation between volume fraction of coarse grains and hardness was found. It was identified by TEM that alumina nano-precipitates stabilize the dislocation microstructure against recovery very effectively and the grain coarsening is due to fast growth of very few dislocation free grains. Thus, the observed grain coarsening has the attributes of static recrystallization. 相似文献
108.
We investigated growth trajectories for classroom performance goal practices and for student behavioral engagement across grades 2 to 5 for 497 academically at-risk elementary students. This study is the first longitudinal investigation of performance goal practices in the early elementary years. On average, teacher use of performance goal practices increased and students' behavioral engagement declined across the four years. Using autoregressive latent trajectory (ALT) models, we examined the synchronous relations between teacher-reported performance goal practices and teacher-reported student behavioral engagement. As expected, as students move into classrooms with a new teacher with less emphasis on performance goal practices, they become more behaviorally engaged in school. Gender did not moderate these results. Implications for teacher professional development are discussed. 相似文献
109.
Previous studies have found that differences in brain volume among older adults predict performance in laboratory tasks of executive control, memory, and motor learning. In the present study we asked whether regional differences in brain volume as assessed by the application of a voxel-based morphometry technique on high resolution MRI would also be useful in predicting the acquisition of skill in complex tasks, such as strategy-based video games. Twenty older adults were trained for over 20 h to play Rise of Nations, a complex real-time strategy game. These adults showed substantial improvements over the training period in game performance. MRI scans obtained prior to training revealed that the volume of a number of brain regions, which have been previously associated with subsets of the trained skills, predicted a substantial amount of variance in learning on the complex game. Thus, regional differences in brain volume can predict learning in complex tasks that entail the use of a variety of perceptual, cognitive and motor processes. 相似文献
110.
Long-term unemployed young people are a ‘social concern’ in many countries. The focus for research is usually cities, but may also include rural areas. The qualitative study described in this paper focuses instead on four young people living in coastal towns in South East England. The study suggests that their experiences in education and employment markets are shaped, negatively, by their particular location and the ongoing opportunity structures. The paper outlines their views and discusses the three main themes that emerged from the analysis: opportunity structures, supported resilience and the impact of living in a coastal town. Implications for targeted youth guidance are considered, alongside a consideration of the reflexive role of the researcher in such work. 相似文献