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221.
健康的贫富差距是指不同社会经济地位的群体在各种健康指标上的系统差异。在过去30余年间, 国外研究揭示了社会经济地位与各种健康指标的负向关系, 并从环境特征和个人特征两个层面对健康的贫富差距做出了解释。以实证证据为基础, 研究者提出了社会文化自我模型、储备能力模型和生物−心理−社会整合模型等理论模型, 尝试从综合的视角理解健康的贫富差距。未来研究应该从多学科跨领域的视角, 使用多样化的研究方法和统计技术深化对健康的贫富差距内在机制的理解, 充分考虑社会文化背景的影响和个体差异的存在, 为促进我国的健康公平实践工作提供切实有效的理论指导。  相似文献   
222.
The typical empirical approach to studying consciousness holds that we can only observe the neural correlates of experiences, not the experiences themselves. In this paper we argue, in contrast, that experiences are concrete physical phenomena that can causally interact with other phenomena, including observers. Hence, experiences can be observed and scientifically modelled. We propose that the epistemic gap between an experience and a scientific model of its neural mechanisms stems from the fact that the model is merely a theoretical construct based on observations, and distinct from the concrete phenomenon it models, namely the experience itself. In this sense, there is a gap between any natural phenomenon and its scientific model. On this approach, a neuroscientific theory of the constitutive mechanisms of an experience is literally a model of the subjective experience itself. We argue that this metatheoretical framework provides a solid basis for the empirical study of consciousness.  相似文献   
223.
Behavioral pharmacology has become increasingly independent of the experimental analysis of behavior. At its beginning, behavioral pharmacology was closely related to the experimental analysis of behavior, with developments in each field aiding the other. Early attempts to systematize data in behavioral pharmacology culminated with the development of the rate-dependency concept, but as this principle was found to have more limited generality than originally was hoped, a theoretical void developed. This circumstance was followed by increased reliance on pharmacological theory as a basis for experimentation and interpretation, with an attendant decrease in emphasis on environmental variables and behavioral interpretations. Lack of interplay between behavioral pharmacology and the experimental analysis of behavior is detrimental to both disciplines because each could contribute significantly to the other. The current trend might be reversed if more research were directed at elucidating behavioral mechanisms of drug action.  相似文献   
224.
The role of parenting styles in the development of young adult narcissism is investigated with individuals from the Block and Block (1980) longitudinal study. At age 3, participants were assessed for the presence of narcissism precursors, and mothers and fathers provided information about their parenting styles. At age 23, the presence of both healthy and maladaptive narcissism was assessed, along with the use of denial. The results showed that parenting styles had a direct effect on the development of healthy narcissism, but the effect on the development of maladaptive narcissism depended on the child’s initial proclivity towards narcissism. Also, the use of denial was positively associated with the presence of maladaptive narcissism, but not with healthy narcissism.  相似文献   
225.
In this study we analyzed 65 fragments of session recordings in which a cognitive behavioral therapist employed the Socratic method with her patients. Specialized coding instruments were used to categorize the verbal behavior of the psychologist and the patients. First the fragments were classified as more or less successful depending on the overall degree of concordance between the patient’s verbal behavior and the therapeutic objectives. Then the fragments were submitted to sequential analysis so as to discover regularities linking the patient’s verbal behavior and the therapist’s responses to it. Important differences between the more and the less successful fragments involved the therapist's approval or disapproval of verbalizations that approximated therapeutic goals. These approvals and disapprovals were associated with increases and decreases, respectively, in the patient’s behavior. These results are consistent with the existence, in this particular case, of a process of shaping through which the therapist modifies the patient’s verbal behavior in the overall direction of his or her chosen therapeutic objectives.  相似文献   
226.
情绪性注意是一种对具有情绪意义的刺激进行选择和加工的注意.由于刺激的情绪效价能调制人脑的感知和注意系统,因而,与对中性刺激的注意相比,情绪性注意的神经机制更加复杂.较早的研究显示,杏仁核对感知皮层的调制对情绪性注意起关键作用.近期的证据表明,杏仁核对注意功能网络的调制可能是其重要的神经机制.本文梳理了相关领域的研究证据,主要强调情绪性刺激对注意的警觉、定向和执行控制网络的调制,发现情绪性注意加工的认知神经机制可能涉及一个以杏仁核为核心的多重功能网络.  相似文献   
227.
In this paper we examine young Germans’ occupational aspirations and the significance of neighborhoods and schools in explaining these aspirations. We aim to show (i) which of the two contexts is more significant in this regard and (ii) by which mechanisms characteristics of these contexts become relevant for youths’ actions or, more precisely, anticipated actions. We conduct our analyses by means of multilevel models. Merging data from Germany’s National Educational Panel Study on 9th grade students with micro-geographic data on residential quarters allows us to consider characteristics of the micro- as well as the meso- and macro-levels. The results show that the school context is considerably more influential on young people’s aspirations than the neighborhoods where they live. This probably reflects the selection of young people into different school types that is characteristic of Germany, a country with a highly stratified school system. Schools do not only shape youths’ career expectations; they are also important places of secondary socialization in that they have an impact on youths’ preferences for particular occupations. Furthermore, we found evidence that the social pressure to aspire high status occupations varies by social composition of the school as well as of the neighborhood context; the effect of neighborhoods, however, is rather weak.  相似文献   
228.
ABSTRACT

The variant selection criteria during β to α phase transformations in a metastable β-titanium alloy (Ti-5553) in the presence of deformation are examined. Two distinct metallurgical states in the β matrix, heavily deformed and fully recrystallized, were obtained from a 90% cold-rolled alloy. The deformed and recrystallized samples were subjected to aging heat treatment for a short time to allow the precipitation of an intragranular α phase. Electron backscattered diffraction was used to assess the α crystallographic variant occurrence in the deformed as well as in the recrystallized β grains. A discrete pole figure analysis revealed that a limited number of variants were evolved in the deformed β grains while there was no variant selection in the recrystallized β matrix. The results suggest that activation of {112}<111>β slip systems determines a strong variant selection in the plastically deformed β matrix.  相似文献   
229.
ABSTRACT

This paper considers the characteristics of severe plastic deformation (SPD) to estimate its efficacy and to compare different processing techniques. In contrast to effective strains by von Mises and Hencky, the rotation component of the strain rate is included in the analysis as a mode of deformation, which ranges from simple shear to pure shear. Distortions of material elements during a uniform plane plastic flow are calculated using a kinematic approach. For the fixed deformation mode, the current state is defined by the accumulated shears that are identical to the von Mises effective shear strains. In specific cases of pure shear and simple shear, the accumulated shears match the specific distortions of round or square elements prescribed by Hencky or von Mises approach, respectively. The mode of deformation is important to the structural effects of SPD. In general, two separated characteristics, accumulated shear and the coefficient of deformation mode, are necessary to describe strains during SPD.  相似文献   
230.
Molecular dynamics simulations are used to show that cyclic mechanical loading can relax the non-equilibrium grain boundary (GB) structures of nanocrystalline metals by dissipating energy and reducing the average atomic energy of the system, leading to higher strengths. The GB processes that dominate deformation in these materials allow low-energy boundary configurations to be found through kinematically irreversible structural changes during cycling, which increases the subsequent resistance to plastic deformation.  相似文献   
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