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881.
The present study investigated the relative extent to which patients' adjustment to chronic low back pain (CLBP) was influenced by their fear-avoidance beliefs, their tendency to catastrophize, and their appraisals of control. Eighty-three CLBP patients completed a series of self-report measures before participating in a physical therapist-led intervention. Hierarchical multiple regression analyses revealed that patients' perceptions of their ability to decrease pain explained a small, but statistically significant, proportion of the variance in pain intensity. In addition, patients' levels of catastrophizing, as well as their fear-avoidance beliefs about both work and physical activity, were independently associated with levels of disability. Interestingly, however, when exploring the relative predictive utility of these three psychological factors, it became evident that fear-avoidance beliefs about physical activity (FABs-PA) were the only significant predictor of patients' disability. Specifically, those patients who exhibited higher levels of FABs-PA tended to report greater levels of disability, even after adjusting for age, sex and pain intensity.  相似文献   
882.
Erik H. Erikson's life cycle schema consists of eight stages. Three are located in infancy and early childhood (ages 1–5), one in childhood (5–12), one in adolescence, and three in adulthood. This essay proposes a relocation of the stages in terms of decades. The eight psychosocial crises in Erikson's model are retained, but each crisis and its resolution is the central theme of a decade of life. This relocation of Erikson's stages orients the life cycle schema more toward adulthood than to early childhood, as six of the stages now occur in the adult years. It also reflects Erikson's theoretical shift in emphasis from the ego to the sense of I in his later writings. A proposal for how the ninth and tenth decades fit into the schema is also offered.  相似文献   
883.
Algebras of Intervals and a Logic of Conditional Assertions   总被引:1,自引:0,他引:1  
Intervals in boolean algebras enter into the study of conditional assertions (or events) in two ways: directly, either from intuitive arguments or from Goodman, Nguyen and Walker's representation theorem, as suitable mathematical entities to bear conditional probabilities, or indirectly, via a representation theorem for the family of algebras associated with de Finetti's three-valued logic of conditional assertions/events. Further representation theorems forge a connection with rough sets. The representation theorems and an equivalent of the boolean prime ideal theorem yield an algebraic completeness theorem for the three-valued logic. This in turn leads to a Henkin-style completeness theorem. Adequacy with respect to a family of Kripke models for de Finetti's logic, ukasiewicz's three-valued logic and Priest's Logic of Paradox is demonstrated. The extension to first-order yields a short proof of adequacy for Körner's logic of inexact predicates.  相似文献   
884.
Subjects in a darkroom saw an array of five phosphorescent objects on a circular table and, after a short delay, indicated which object had been moved. During the delay the subject, the table or a phosphorescent landmark external to the array was moved (a rotation about the centre of the table) either alone or together. The subject then had to indicate which one of the five objects had been moved. A fully factorial design was used to detect the use of three types of representations of object location: (i) visual snapshots; (ii) egocentric representations updated by self-motion; and (iii) representations relative to the external cue. Improved performance was seen whenever the test array was oriented consistently with any of these stored representations. The influence of representations (i) and (ii) replicates previous work. The influence of representation (iii) is a novel finding which implies that allocentric representations play a role in spatial memory, even over short distances and times. The effect of the external cue was greater when initially experienced as stable. Females out-performed males except when the array was consistent with self-motion but not visual snapshots. These results enable a simple egocentric model of spatial memory to be extended to address large-scale navigation, including the effects of allocentric knowledge, landmark stability and gender.  相似文献   
885.
The latent structure of the Penn State Worry Questionnaire (PSWQ) was evaluated with confirmatory factor analyses (CFAs) in 1200 outpatients with DSM-IV anxiety and mood disorders. Of particular interest was the comparative fit and interpretability of a two-factor solution (cf. Behaviour Research and Therapy 40 (2002) 313) vs. a one-factor model that specified method effects arising from five reverse-worded items. Consistent with prediction, the superiority of the one-factor model was demonstrated in split-sample CFA replications (ns=600). Multiple-group CFAs indicated that the measurement properties of the PSWQ were invariant in male and female patients. In addition to their direct relevance to the psychometrics of the PSWQ, the results are discussed in regard to methodological considerations for using factor analytic methods in the evaluation of psychological tests.  相似文献   
886.
The study of unconscious processes leads to the hypothesis of the limit of consciousness, which involves two main kinds of psychic activity. The first represents psychic contents which are subliminal for their low energy, the second subliminal contents which are inaccessible to consciousness because they are dissociated in the subliminal region. Dissociation is a concept introduced by Pierre Janet for splitting consciousness due to traumatic events or during hypnosis. It takes a more general form in Hilgard's neo-dissociation theory of hypnotic phenomena and also in Jung's theory of the collective unconscious. Further generalization links it to the modern findings of explicit and implicit perception, leading to a shift in dissociation from hypothesis to clinical, experimental and theoretical reality. Studies in hypnosis also point to the existence of an integrative psychic entity, that comprises the conscious 'I'. Hilgard called this the hidden observer, and his findings represent empirical confirmation of Jung's term for the Self as mirror 'I', which leads to many important consequences for self-discovery and the meaning of life.  相似文献   
887.
This paper forms an introduction to this issue, the contents of which arose directly or indirectly from a conference in May 2001 on Corruption of scientific integrity? — The commercialisation of academic science. The introduction, in recent decades, of business culture and values into universities and research institutions is incompatible with the openness which scientific and all academic pursuit traditionally require. It has given rise to a web of problems over intellectual property and conflict of interest which has even led to corporate sponsors’ suppressing unfavourable results of clinical trials, to the detriment of patients’ health. Although there are those who see the norms of science developing to recognise the importance of instrumental science aiming at specific goals and of knowledge judged by its value in a context of application, none justifies the covert manipulation of results by vested interest.Public awareness of these problems is growing and creating a climate of opinion where they may be addressed. We suggest a way forward by the introduction of nationally and internationally-accepted guidelines for industrial collaboration which contain proper protections of the core purposes of universities and of the independence of their research. Some codes suggested for this purpose are discussed. We note that some universities are moving to adopt such codes of conduct, but argue the need for strong support from the government through its funding bodies.  相似文献   
888.
A survey on ethical issues in engineering was administered over a five-year period to Stanford engineering students and practicing engineers. Analysis of its results strongly suggests that important disconnects exist between the education of engineering students regarding ethical issues in engineering on the one hand, and the realities of contemporary engineering practice on the other. Two noteworthy consequences of these gaps are that the views of engineering students differ substantially over what makes an issue an ethical issue, while practicing engineers exhibit significant disagreement over what is the most important non-technical aspect of being a responsible engineering professional in contemporary society. These divergences impede the recognition of ethical issues and of specific moral responsibilities of engineers in concrete professional practice. It is argued that the use of suitably refined and probing surveys of engineering students and practicing engineers about ethical issues in engineering is an important although neglected empirical approach to the study of engineering ethics. Such an approach can enhance the prevailing case study method and combat over-tidy theoretical-analytical approaches to the subject. When a train arrives at a station in the London Underground, a public announcement cautions passengers to “mind the gap”, i.e. heed the space between the station platform and the carriage while entering or exiting. An early draft of this paper was presented at the International Conference on Ethics in Engineering and Computer Science, Case Western Reserve University, Cleveland, Ohio, March 21–23, 1999.  相似文献   
889.
This article focuses mainly on (1) the policy of Delft University of Technology since 1992 as regards the university-wide introduction of a compulsory course on ethics and engineering, and (2) the ideal structure of such a course, including the educational goals of the course. Dr. G. J. Scheurwater is Senior policy-advisor to the Board of Delft University of Technology. Prof. S. J. Doorman is Chairman of the Advisory Committee on Ethics of Delft University of Technology.  相似文献   
890.
Environmentalists have advocated the Precautionary Principle (PP) to help guide public and private decisions about the environment. By contrast, industry and its spokesmen have opposed this. There is not one principle, but many that have been recommended for this purpose. Despite the attractiveness of a core idea in all versions of the principle—that decision-makers should take some precautionary steps to ensure that threats of serious and irreversible damage to the environment and public health do not materialize into harm—even one of the most widely endorsed principles needs considerable specification and refinement before it can be used. Moreover, the PP is an approach or guide to utilizing scientific evidence in social or legal decision-making contexts. In this it does not differ in kind from other approaches to using factual information such as in the law. The law provides some models for different strategies to guide decision-making under uncertainty when factual issues cannot be resolved with certainty. These in turn can help guide the formulation of different versions of PP and help clarify some presuppositions of the principle. Once some plausible versions of PP are articulated, I suggest some applications to existing environmental problems.  相似文献   
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