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961.
The current studies examine proximal and distal mortality salience effects on the willingness to engage in health-promoting activities and explore the roles of age and self-esteem. In Study 1, 164 participants completed a self-esteem scale, were assigned to a mortality salience or a neutral condition, and then completed a scale, tapping their willingness to engage in health promoting activities. Findings revealed that in the proximal mode, mortality salience led the young and middle-aged adults to report higher willingness to promote health behaviors, whereas older adults tended to show a lower willingness to promote their health compared to the control condition. In Study 2, a total of 251 participants completed the same series of questionnaires, including a distracting task immediately after the mortality salience manipulation. Findings revealed that, in the distal mode, whereas death reminders did not affect young adults, mortality salience led middle-aged participants to express higher willingness to conduct health-promoting behaviors than in a control condition. The mortality salience induction did not affect older adults with high self-esteem, but led low self-esteem individuals to report higher willingness to promote their health. The differences between the reactions of the different age groups in both the defense modes are discussed in view of the terror management theory.  相似文献   
962.
Abstract

Recent theoretical and empirical research has challenged the assumption of health psychologists employing social cognitive models that beliefs can confidently be inferred on the basis of questionnaire responses. It is charged that responses to questionnaires are a function of the intelligibility of the items, constructs and theoretical framework to survey participants. To investigate this contention, cognitions specified by Protection Motivation Theory (PMT) were measured with respect to intentions to use a condom and intentions to use dental floss. Three alternative formats of a questionnaire which varied the order of presentation of PMT items were distributed to student samples. Analyses showed that while questionnaire format did not affect the reliability of cognition measures, there was some variation in the significance and strength of correlations between PMT cognitions across formats. Individual differences in social desirability and salience of the target behaviour had small and predictable effects upon reliabilities and intercorrelations. Implications for the measurement of health beliefs and the status of questionnaire responses are outlined and suggestions are made for controlling bias associated with respondents' capacity to “read” a questionnaire.  相似文献   
963.
ABSTRACT

We present results for the structural, electronic, vibrational, and electron-phonon coupling properties of LaSn3 and CaSn3 adopting the simple cubic AuCu3-type structure obtained using the the generalised gradient approximation of the density functional theory and plane wave ab initio pseudopotential method. Our electronic results show that both materials display metallic character with several bands, which have mainly Sn 5p character, crossing the Fermi level. The calculated phonon spectrum of LaSn3 accords very well with reported experimental measurements. The weights of the peaks in the Eliashberg spectral function of both compounds are enhanced with the use of experimental lattice constant in our electron-phonon calculation, increasing the value of average electron phonon coupling parameter from 0.876 to 0.937 for LaSn3 (by 7%) and from 0.642 to 0.725 for CaSn3 (by 13%). The use of experimental lattice constant also improves the agreement between theoretical and experimental values of the superconducting temperature for both compounds.  相似文献   
964.

Secondary ageing, that is microstructural evolution occurring at room temperature after short heating at temperatures above the metastable phase boundary of Guinier-Preston zones, has been studied for an Al-Cu-Mg alloy with a high Cu-to-Mg ratio. Combined data from positron annihilation spectroscopy, Vickers microhardness measurements and differential scanning calorimetry show that, on secondary ageing after 5 or 7min at 190°C, firstly, hardening takes place at a rate nine to 16 times slower than natural age hardening; secondly, vacancies slowly released by Cu-rich aggregates formed during the heat treatment at 190°C promote further formation of solute aggregates, with a time-dependent chemical composition; thirdly, the thermal stability of the structures formed during secondary ageing increases with increasing dwell time at room temperature; and, fourthly, solute aggregates formed at 190°C undergo a structural reorganization and possibly a change in the composition, leading to species with a different thermal stability. The slow release of vacancies from Cu-rich aggregates is proposed as one of the limiting factors of the hardening rate.  相似文献   
965.

In a study of radiation effects in SnO we have found that electron-beam damage is observable from changes in a high-resolution electron microscopy image or electron diffraction pattern. The early stage of the damage is not accompanied by a change in composition or a loss of crystallinity. The dose required for this damage (about 600 C cm?2) is approximately independent of electron energy (between 100 and 400 keV) and specimen temperature (between 100 and 300 K). The damage is believed to start with displacement of oxygen atoms from their lattice position through a radiolytic mechanism with an efficiency of approximately 10?4.  相似文献   
966.
967.
This investigation adapts and extends the Social Cognitive Career Theory (SCCT) by integrating it with central constructs from turnover theory. The extended model proposes that domain specific self-efficacy and outcome expectations predict job satisfaction and organizational commitment — the two key job attitudes that have been established as influential predictors of turnover cognitions and behaviors. Further, we proposed that one form of organizational supports, specifically developmental opportunities at work, are sources of self efficacy and outcome expectations, and that the relationship between organizational supports and job attitudes is mediated by self-efficacy and outcome expectations. The proposed model was tested on a national sample of 2,042 women engineers. Overall, the results provided support for our newly developed model. Implications for theory, research, and practice are discussed.  相似文献   
968.
Orthodox decision theory gives no advice to agents who hold two goods to be incommensurate in value because such agents will have incomplete preferences. According to standard treatments, rationality requires complete preferences, so such agents are irrational. Experience shows, however, that incomplete preferences are ubiquitous in ordinary life. In this paper, we aim to do two things: (1) show that there is a good case for revising decision theory so as to allow it to apply non-vacuously to agents with incomplete preferences, and (2) to identify one substantive criterion that any such non-standard decision theory must obey. Our criterion, Competitiveness, is a weaker version of a dominance principle. Despite its modesty, Competitiveness is incompatible with prospectism, a recently developed decision theory for agents with incomplete preferences. We spend the final part of the paper showing why Competitiveness should be retained, and prospectism rejected.  相似文献   
969.
Stress and self‐esteem have been shown to be important risk factors for adolescent cigarette smoking, and self‐esteem has previously been implicated as a stress‐moderating and a stress‐mediating variable. This study aimed to examine the associations between stress, area‐specific self‐esteem, and adolescent smoking, and to investigate whether specific areas of self‐esteem moderate or mediate the relationship between stress and smoking. Four hundred and ninety‐five adolescents (aged 14–19) responded to a questionnaire that examined these variables. Results showed that self‐esteem in the areas of school subjects and parent relations were related to smoking. Adolescents with low self‐esteem in these areas were more likely to smoke than their high self‐esteem counterparts. Highly stressed adolescents were more likely to smoke than those with low stress. However, the relationship between stress and smoking was completely mediated by self‐esteem in the area of school subjects. No moderation was revealed. Thus, high global self‐esteem may not be sufficient to reduce the risk of smoking. To maximise benefit, prevention and intervention efforts should target self‐esteem in the areas of school subjects and parent relations. Initiatives focusing on stress are only likely to decrease smoking to the extent that they influence self‐esteem in the area of school subjects.  相似文献   
970.
The self as a psychological construct, and the self in relation to the other has been discussed in psychological and sociological literature for decades, but not much attention has been given to the psychological development of the self in relation to the social construction of prejudice. The primary aim of this article is to explore the self in prejudice and thus the psychological processes involved in the development of self within the social context. Consequently, the aim is to explore the self in the construction and expression of prejudice from both a social and psychological approach, and to explain selfhood influences at the individual, group and community levels. I use the conceptual framework of Kohut's self psychology as a lens to present the development of the self and thus the idea of the development of the self in relation to the other. In such exploration of self in prejudice, I present some of my ideas which include prejudice as an outcome of self-definition in the context of the other, as well as linking self in prejudice and group dynamics to attachment theory and the notion of “selfgroup’ in terms of overidentification with the in-group. While the social and the psychological in terms of the development of the self cannot be separated, I have therefore attempted to merge at some point the two bodies of thought in relation to the self in prejudice.  相似文献   
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