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81.
Abstract

A quasicrystalline Al-Fe phase has been formed by room-temperature ion mixing of AI-Fe multiple layers with no additional postannealing. The quasicrystalline phase was dispersed as grain in an amorphous matrix. The size of the grains was about 10-30nm, and the composition was determined to be Al80Fe20. The structure of the quasicrystalline phase was identified by calculating some 20 sharp diffraction rings in the selected-area diffraction pattern and found to be similar to that of the rapidly quenched AI-Mn quasicrystalline phase.  相似文献   
82.
随着社会老龄化的加剧,盆底功能障碍性疾病的发病率日益上升.之前热门的盆底重建术随着时间的推移,并发症相继出现.美国食品药品管理局(FDA)连续两次发布了关于经阴道网片的警告,使专家们认识到了问题的严重性.经过30余年的发展,腹腔镜技术已经被广泛地应用于各类妇科手术中.腹腔镜在女性盆底修复术中的应用重新得到了关注.自1991年腹腔镜技术首次应用于女性盆底修复手术中以来,国内外不断有新的腹腔镜下盆底修复术式的报道.现就各种腹腔镜下盆底修复手术做一综述.  相似文献   
83.
该研究探索元认知在线监控和离线监控与一般元认知能力之间的关系,采用跟踪击键任务、学习判断任务和大学生元认知能力量表,对40名大学生进行研究。结果表明:(1)元认知离线监控对一般元认知能力各个子成分的预测作用受元认知在线监控的影响;(2)元认知在线、离线监控对一般元认知能力的预测作用是彼此独立的。  相似文献   
84.
This article introduces the concept of law-encoding diagrams (LEDs) and presents the argument that they have had a role in scientific discovery that has not been previously recognized. An LED is a representation that correctly encodes the underlying relations of a law, or a system of simultaneous laws, in the structure of a diagram by the means of geometric, topological, and spatial constraints, such that the instantiation of a particular diagram represents a single instance of the phenomena or a particular case of the law(s). Examples of LEDs in the history of science are discussed, and the benefits of using LEDs in discovery are considered. LEDs are distinguished from other forms of diagrammatic representation. Previous work on the computational modeling of diagrammatic law induction is reinterpreted in terms of the search for diagrammatic constraints of LEDs. A general characterization of the role of LEDs in discovery is considered, and a framework for classifying processes of discovery based on LEDs is proposed.  相似文献   
85.
The influence of vehicular control on motion sickness has implications for theories of motion sickness etiology. We asked whether motion sickness susceptibility might also be related to the control of non-vehicular locomotion. Participants were exposed to a console video game that featured ambulatory locomotion of a virtual avatar. In a yoked control design, individuals either played the game (players) or watched another participant's recorded game play (viewers). Viewers were more likely than players to report motion sickness. During exposure to the video game players moved more than viewers, and the movement of players was more predictable or self-similar than the movement of viewers. Coupling of movement within player-viewer pairs was greater for pairs in which the viewer later reported motion sickness than for pairs in which both participants stated that they were not motion sick. The results reveal that motion sickness incidence can be influenced by the control of stimulus motion, in general, and is not limited to control of vehicular motion. We discuss implications of these findings for theories of motion sickness etiology.  相似文献   
86.
Jesse Bering (2002) investigated how American university students in an interview task conceived of dead persons' mentality immediately after death. He found that different categories of mental states or capacities were conceived differently: psychobiological and perceptual states ceased, whereas emotional, desire, and epistemic states continued. Our Study 1 was a replication of Bering's experiment in a different cultural setting, in which the subjects were Chinese undergraduate students. A similar pattern of results was found. In Study 2, instead of being asked about a dead person's various mental states immediately following the death, participants were asked to judge a dead person's mental states after the person had been dead for 2 days. The overall pattern of participants' responses was not affected by this manipulation, but they did show an increase in attributions of certain mental states to dead agnostics. In addition, a more refined breakdown of responses revealed that individuals tended to judge that, upon death, visual and auditory perception continued, whereas olfactory and gustatory sensation ceased.  相似文献   
87.
Most impulse purchasing research investigates individual‐level factors. This paper, however, examines the influence of shopping companion gender on impulse purchasing. The results of the three studies show that shoppers were more likely to exhibit impulse purchase behavior when shopping with an opposite gender companion. In addition, shoppers who were in the low‐cohesive condition and who shopped with an opposite gender companion were more likely to exhibit impulse purchase behavior than those who shopped with the same gender companion, and those who were susceptible to interpersonal influence were also more likely to exhibit impulse purchase behavior when shopping with an opposite gender companion. For shoppers who were not as susceptible to interpersonal influence, the influence of their companion's gender appeared to diminish on impulsive purchasing.  相似文献   
88.
This review examines the phenomenon of hate crimes in the United States. Findings derived from the FBI data for the period 1996–2008 revealed that the incidence of anti‐racial hate crimes varied among different racial groups, that antireligious hate crimes were committed toward Jews and Muslims more than toward others, and that antisexual orientation hate crimes focused on male homosexuals more than others. Antireligious hate crimes were more likely to be directed against property, whereas anti‐racial and antisexual orientation hate crimes were more likely to be directed against people. We discuss these findings in the light of some relevant theoretical perspectives from social psychology. Potential solutions to hate crimes could be developed by focusing on the most relevant predictive factors.  相似文献   
89.
Racial conflict between African Americans and Whites has been observed to occur most frequently at two critical points: when African Americans make up approximately 30% of a given group or when African Americans make up approximately 50% of a given group. These two critical ratios are referred to as the J and (inverted) U patterns of racial conflict, respectively. To date, most of the data supporting either the J or U models have been derived from large demographic studies that do not directly assess individual perceptions. Thus, little is known about the individual reactions of members from either racial group to varying percentages of group racial composition. This small-group experiment examined the responses of African-American and White subjects to their inclusion in four-person groups of varying racial compositions. Three racial configurations were created and included the following percentages of African Americans: 25%, 50%, and 75%. The results support the U model of racial conflict. Moreover, the U model fit the data equally well for African Americans and Whites.  相似文献   
90.
Event-related potentials (ERPs) were obtained from 15 electrode sites in six average and six impaired reading children, 12 years of age, during visual letter discrimination tasks. Subjects responded to target letters with an enclosed area in the form task and to letters that rhymed with “e” in the rhyme task. Response accuracy was similar between the groups. Reaction time was relatively longer for the impaired group during the rhyme task. At lateral sites, condition differences were evident as greater negative shifts in the rhyme task than the form at 170 and 470 ms as well as a delayed late positivity for the rhyme. In terms of reading ability, the average readers’ ERPs were more negative than those of the impaired group at 270 and 450 ms. Interhemispheric variations were also seen between the groups, with the average readers more negative than the impaired readers at right hemisphere sites. Contrary to expectations, group differences in the ERP did not vary substantially as a function of condition, and task demands were evaluated in view of these findings.  相似文献   
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