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1.
The internal length is the governing parameter in strain gradient theories which among other things have been used successfully to interpret size effects at the microscale. Physically, the internal length is supposed to be related with the microstructure of the material and evolves during the deformation. Based on Taylor hardening law, we propose a power-law relationship to describe the evolution of the variable internal length with strain. Then, the classical Fleck–Hutchinson strain gradient theory is extended with a strain-dependent internal length, and the generalized Fleck–Hutchinson theory is confirmed here, by comparing our model predictions to recent experimental data on tension and torsion of thin wires with varying diameter and grain size. Our work suggests that the internal length is a configuration-dependent parameter, closely related to dislocation characteristics and grain size, as well as sample geometry when this affects either the underlying microstructure or the ductility of the material.  相似文献   

2.
The historic importance of Freud's analysis of the Schreber case is acknowledged, even though the theory it expounds is largely disavowed. The theory ascribes the cause of paranoid delusion to homosexual impulses unresolved in infancy or early childhood. This paper summarizes Freud's monograph on Schreber and contrasts his theory with the views of various revisionists. The writers focus on the Freudian concept of projection, which is intended to explain how much meaning can become reversed under the impetus of stress, and the reversal lead to delusional thinking. Based on their work in family therapy, where they observed one form of pathogenic relating termed learning to be possessed, the writers concluded that this form was also based on a type of projection which could culminate in delusional ideation. A relationship between learning to be possessed and H. S. Sullivan's theory of paranoid transformation is described. A learning factor is present in several of the psychological theories advanced to explain delusion, and the factor is akin to if not identical with Freud's concept of projection.Gerald Zuk, PhD, is in private practice at 25316 Pacy Street, Santa Clarita, California 91321-3343. Carmen Zuk, MD, is a child psychiatrist-partner affiliated with the Southern California Permanente Medical Group at its psychiatric clinic in Van Nuys, California. Both may be reached by telephone at (805) 252-7702.  相似文献   

3.
Twenty-two pairs of typically developing toddlers (M = 24.32 months) and their mothers were observed in a play-room solving puzzles during 30 min. The target of the observations was hand-taking gesture. Researchers have thought that this gesture is rare among typically developing children and is more frequent among autistic children. Ten in 22 children showed this gesture in only 30 min. They should know “I can not do it by myself, but my mother can do it.” When we can assume that children know others’ mental mechanism, it might be the origins of a theory of mind.  相似文献   

4.
The formation of two misfit edge dislocations is theoretically investigated in the interfaces of a layer embedded in a semi-infinite matrix. Assuming the matrix–layer interfaces are partially coherent, the energy variation resulting from the formation of the dislocations from the lateral free surface of the structure has been determined in the shearing stress field due to the partial misfit. The mechanical stability of the structure is analysed with respect to the dislocation formation as a function of the size of the coherent region of the interface and the misfit strain.  相似文献   

5.
This article explains how the meta‐theoretical framework of critical realism addresses methodological issues of concern to social psychologists and social scientists. The article outlines key tenets of critical realism – its notion of the stratified nature of reality and generative mechanisms as powers in natural and social objects that cause things; its notion of knowledge of reality as stratified rather than only empirical; its acceptance of epistemological but not judgmental relativism; and its monist ontology. The article then introduces realist social theory to provide a framework for understanding the society–person connection. It explains how issues relating to culture, context, and society raised in the indigenous psychology English literature might be addressed from a critical realist perspective. Some implications arising from adopting a critical realist perspective in research practice are outlined and social psychologists and social scientists are encouraged to explore the potential of critical realism as a meta‐theoretical framework and new paradigm.  相似文献   

6.
Since its formal definition over sixty years ago, category theory has been increasingly recognized as having a foundational role in mathematics. It provides the conceptual lens to isolate and characterize the structures with importance and universality in mathematics. The notion of an adjunction (a pair of adjoint functors) has moved to center-stage as the principal lens. The central feature of an adjunction is what might be called “determination through universals” based on universal mapping properties. A recently developed “heteromorphic” theory about adjoints suggests a conceptual structure, albeit abstract and atemporal, for how new relatively autonomous behavior can emerge within a system obeying certain laws. The focus here is on applications in the life sciences (e.g., selectionist mechanisms) and human sciences (e.g., the generative grammar view of language).
David EllermanEmail:
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7.
The role of activation (arousal and subjective significance) was investigated for word processing in an explicit emotional judgement task using a 3?×?3 manipulation. We expected to find dissociative effects for both factors. The behavioural results showed that the fraction of words perceived as emotional increases with increasing arousal or subjective significance. The electrophysiological (EEG) results showed that both factors influence ERP amplitudes. General effects of subjective significance were found for early (60–120?ms and 120–250?ms, low subjective significant stimuli evoked higher amplitude than other conditions) and late (350–490?ms, high subjective significant stimuli evoked higher amplitude than other conditions) time ranges. Localised arousal effects were found in 250–350?ms and 350–490?ms time ranges at posterior (amplitude for high arousing stimuli was less positive than for other conditions) and left frontal ROIs (diverse pattern). Localised subjective significance effects were found for the 350–490?ms time range at the posterior ROIs (amplitude for high subjective significant stimuli was more positive than for other conditions). The results of this study suggest that the effects of arousal reported in earlier studies might account for a more complex form of activation that was recently postulated, namely subjective significance.  相似文献   

8.
The paper outlines a conceptual framework for the critical assessment of argumentation which differs in some of its core characteristics from conventional approaches: it is resolutely semantic rather than formal in its method; it centers on obligations rather than beliefs; and its analytical focus is on the contingent necessity of conclusions, rather than on their persuasiveness or formal validity. The paper briefly illustrates the applications of this conceptual framework by reanalyzing a couple of examples taken from the argumentation analysis literature.  相似文献   

9.
Objective: To synthesise theory of planned behaviour (TPB) relationships, using meta-analysis, and test the predictive utility of the model for sun protection behaviour.

Design: Thirty-eight samples were identified via database/manual searches and academic society posts based on the criteria: measuring sun-protective intentions and/or prospective behaviour; using the TPB/theory of reasoned action as a basis of measurement; and providing bivariate correlations for at least one relevant TPB association.

Main outcome measures: Sun-protective intentions and behaviours.

Results: The sample-weighted average effects were moderate-to-strong with attitudes showing the strongest association with intention (r+ = 0.494), followed by perceived behavioural control (PBC; r+ = 0.451), and subjective norm (r+ = 0.419). Intentions showed a stronger association with prospective behaviour (r+ = 0.486) compared to PBC (r+ = 0.314). A total of 39% of variance in intentions and 25% of variance in behaviour were explained. Publication bias was not evident. Moderator analyses showed that TPB associations were stronger when measures specified the Target, Action, Context and Time; in non-student samples; and when follow-up exceeded two weeks.

Conclusion: Despite recent criticism, this review shows that the TPB explains a large amount of variance in sun protection and that TPB associations are robust across different populations.  相似文献   


10.
The pace of change in the world is accelerating, yet educational institutions have not kept pace. Indeed, schools have historically been the most static of social institutions, uncritically passing down from generation to generation outmoded didactic, lecture-and-drill-based, models of instruction. Predictable results follow. Students, on the whole, do not learn how to work by, or think for, themselves. They do not learn how to gather, analyze, synthesize and assess information. They do not learn how to analyze the diverse logic of the questions and problems they face and hence how to adjust their thinking to those problems. They do not learn how to enter sympathetically into the thinking of others, nor how to deal rationally with conflicting points of view. They do not learn to become critical readers, writers, speakers and listeners. They do not learn how to use their native languages clearly, precisely, or persuasively. They do not, therefore, become literate, in the proper sense of the word. Neither do they gain much in the way of genuine knowledge since, for the most part, they could not explain the basis for what they believe. They would be hard pressed to explain, for example, which of their beliefs were based on rational assent and which on simple conformity to what they have been told. They have little sense as to how they might critically analyze their own experience, or identify national or group bias in their own thinking. They are much more apt to learn on the basis of irrational than rational modes of thought. They lack the traits of mind of a genuinely educated person: intellectual humility, courage, integrity, perseverance, and faith in reason.Happily, there is a movement in education today striving to address these problems in a global way, with strategies and materials for the modification of instruction at all levels of education. At its foundation is an emerging new theory of knowledge, learning, and literacy, one which recognizes the centrality of independent critical thinking to all substantial learning, one which recognizes that higher-order, multilogical thinking is as important to childhood as to adult learning, and as important to foundational learning in monological as in multilogical disciplines. This educational reform movement is not proposing an educational miracle cure, for its leading proponents recognize that many social and historical forces must come together before the ideals of the critical thinking movement will become a full academic reality. Schools do not exist in a social vacuum. To the extent that the broader society is uncritical so, on the whole, will be society's schools. Nevertheless, the social conditions necessary for fundamental changes in schooling are increasingly apparent. The pressure for fundamental change is growing. Whether and to what extent these needed basic changes will be delayed or side-tracked, thus requiring new periodic resurgences of this movement, with new, more elaborate articulations of its ideals, goals, and methods — only time will tell.  相似文献   

11.
Abstract

This paper reports on a study carried out to identify predictors of uptake of cervical screening among 142 women (59% response rate) in inner London. Two social cognition models were used: The Health Belief Model (HBM; Becker, 1974) and the Theory of Planned Behaviour (TPB; Ajzen, 1991) and in addition anticipated affect following non-attendance for screening was assessed. The TPB emerged as by far the superior model for predicting screening intentions, explaining 51% of the variance in comparison with only 4% explained by the HBM variables. However, neither model was able to predict a significant amount of variance in uptake of screening three months later. Possible reasons for the poor prediction of this type of behaviour are discussed.  相似文献   

12.
Self-projection is the ability to orient the self in different places in time and space. Episodic memory, prospection, and theory of mind (ToM) are all cognitive abilities that share an element of self-projection. Previous research has posited that each of these abilities stems from the same neural network. The current study compared performance of cognitively healthy older adults and younger adults on several self-projection tasks to examine the relatedness of these constructs behaviorally. Episodic memory and prospection were measured using an episodic interview task where the participants were asked to remember or imagine events that either had happened in the past or could happen in the future and then gave ratings describing the extent to which they were mentally experiencing the event and from what perspective they viewed it. ToM was measured by asking participants to make judgments regarding the intentions of characters described in stories that involved cognitive, affective, or ironic components. Our results demonstrate that aging influences episodic memory, prospection, and ToM similarly: older adult participants showed declines on each of these measures compared to younger adults. Further, we observed correlations between performance on the measures of episodic memory and prospection as well as between episodic memory and ToM, although no correlation between prospection and ToM was observed after controlling for chronological age. We discuss these results in the light of theories suggesting that each of these abilities is governed by a common brain system.  相似文献   

13.
Abstract

The present study examined the relationships among the theory of planned behavior (TPB), stages of change, and exercise behavior in 131 older persons over a three year period. Participants completed a baseline questionnaire by mail that assessed attitude, perceived control, subjective norm, intention, and stage and then received a telephone call three years later in which current exercise stage and behavior were assessed. Path analyses showed that (a) TPB constructs were significant predictors of exercise stage, (b) intention mediated the effects of TPB constructs on exercise stage, and (c) exercise behavior was best predicted by intention rather than stage. Results were interpreted as providing evidence for the long term predictive validity of TPB in the exercise domain and as questioning the necessity of combining both intention and stage in a single predictive model.  相似文献   

14.
Given the increasing importance of heterosexual HIV-transmission in Europe and Switzerland, the present study tested the theory of planned behaviour (TPB) in a prospective study on the HIV-protection behaviour in a community sample of heterosexual men. The study focused on condom use in sexual encounters with new partners. Participants were 982 Swiss men between the ages of 25 and 65 who were surveyed using standardised questionnaires in two computer-assisted telephone interviews that took place in autumn 2002 and spring 2003. The TPB was able to predict condom use in sexual encounters with new and casual partners. In accordance with the theory, condom use was predicted by intention. Perceived behavioural control and attitude were significant predictors of intention, whereas subjective norm was not. Thus, in line with other studies, the present study highlighted the somewhat limited explanatory power of the theory. Further theoretical and empirical work is needed to develop extensions to the theory.  相似文献   

15.
The author views Isaacs's (1952) paper, The nature and function of phantasy, as making an important contribution to the development of a radically revised psychoanalytic theory of thinking. Perhaps Isaacs's most important contribution is the notion that phantasy is the process that creates meaning, and that phantasy is the form in which all meanings - including feelings, defense 'mechanisms,' impulses, bodily experiences, and so on - exist in unconscious mental life. The author discusses both explicit formulations offered by Isaacs as well as his own extensions of her ideas. The latter include (1) the idea that phantasying generates not only unconscious psychic content, but also constitutes the entirety of unconscious thinking; (2) the notion that transference is a form of phantasying that serves as a way of thinking for the first time (in relation to the analyst) emotional events that occurred in the past, but were too disturbing to be experienced at the time they occurred and (3) a principal aim and function of phantasy is that of fulfilling the human need to get to know and understand the truth of one's experience. The author concludes by discussing the relationship between Isaacs's concept of phantasy and Bion's concepts of alpha function and the human need for the truth, as well as the differences between Fairbairn's and Isaacs's conceptions of the nature of unconscious internal object relationships.  相似文献   

16.
17.
Abstract

The purposes of the study were threefold. First, to test the validity of Ajzen's (1991) theory of planned behavior (TPB) in predicting intended contraception in the Ethiopian cultural setting. Second, to examine the additional predictive roles of past behavior and perceived pregnancy risk in the TPB model. Third, to identify the salient contraceptive beliefs influencing intended contraception. Data stemmed from a community sample of 354 sexually active female adolescents aged 15 to 19 years. The findings of the study supported TPB as a robust model in Ethiopian cultural setting, with subjective norm being the strongest predictor of intended contraception. In addition, both past contraceptive behavior and perceived pregnancy risk demonstrated to have significant contributions in predicting intention over and above that explained by attitude, subjective norm and perceived behavioral control elements of the TPB. Moreover, the study also identified salient and important contraceptive beliefs that need to be addressed in family life education and counseling programs designed for adolescents and the youth.  相似文献   

18.
Eight human subjects pressed a lever on a range of variable-interval schedules for 0.25¢ to 35.0¢ per reinforcement. Herrnstein's hyperbola described seven of the eight subjects' response-rate data well. For all subjects, the y-asymptote of the hyperbola increased with increasing reinforcer magnitude and its reciprocal was a linear function of the reciprocal of reinforcer magnitude. These results confirm predictions made by linear system theory; they contradict formal properties of Herrnstein's account and of six other mathematical accounts of single-alternative responding.  相似文献   

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