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891.
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   
892.
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   
893.
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   
894.

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   
895.

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   
896.
897.
Aftereffects of adaptation have revealed both independent and interactive coding of facial signals including identity and expression or gender and age. By contrast, interactive processing of non-linguistic features in voices has rarely been investigated. Here we studied bidirectional cross-categorical aftereffects of adaptation to vocal age and gender. Prolonged exposure to young (~ 20 yrs) or old (~ 70 yrs) male or female voices biased perception of subsequent test voices away from the adapting age (Exp. 1) and the adapting gender (Exp. 2). Relative to gender-congruent adaptor-test pairings, vocal age aftereffects (VAAEs) were reduced but remained significant when voice gender changed between adaptation and test. This suggests that the VAAE relies on both gender-specific and gender-independent age representations for male and female voices. By contrast, voice gender aftereffects (VGAEs) were not modulated by age-congruency of adaptor and test voices (Exp. 2). Instead, young voice adaptors generally induced larger VGAEs than old voice adaptors. This suggests that young voices are particularly efficient gender adaptors, likely reflecting more pronounced sexual dimorphism in these voices. In sum, our findings demonstrate how high-level processing of vocal age and gender is partially intertwined.  相似文献   
898.
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   
899.
Valedictory     
Contingentism, generally contrasted with law necessitarianism, is the view that the laws of nature are contingent. It is often coupled with the claim that their contingency is knowable a priori. This paper considers Bird's [2001 Bird, Alexander 2001. Necessarily, Salt Dissolves In Water, Analysis 61/4: 26774.[Crossref], [Web of Science ®] [Google Scholar], 2002 Bird, Alexander 2002. On Whether Some Laws Are Necessary, Analysis 62/3: 25770.[Crossref], [Web of Science ®] [Google Scholar], 2005 Bird, Alexander 2005. Unexpected A Posteriori Necessary Laws of Nature, Australasian Journal of Philosophy 83/4: 53348.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar], 2007 Bird, Alexander 2007. Nature's Metaphysics: Laws and Properties, Oxford: Clarendon Press.[Crossref] [Google Scholar]] arguments for the thesis that, necessarily, salt dissolves in water; and it defends his view against Beebee's [2001] and Psillos's [2002 Psillos, Stathis 2002. Salt Does Dissolve In Water, But Not Necessarily, Analysis 62/3: 2557.[Crossref], [Web of Science ®] [Google Scholar]] contingentist objections. A new contingentist objection is offered and several reasons for scepticism about its success are raised. It is concluded that certain higher-level laws describing the behaviours of molecular compounds may be necessary due to their dependence on underlying physical laws, and that the modal status of laws of nature cannot be determined a priori, as the structural features of the substances and properties they govern must first be investigated.  相似文献   
900.
Proponents of the subset account of property realization commonly make the assumption that the summing of properties entails the summing of their forward-looking causal features. This paper seeks to establish that this assumption is false. Moreover, it aims to demonstrate that without this assumption the fact that the subset account captures an entailment relation—which it must if it is to be of any use to non-reductive physicalism—becomes questionable.  相似文献   
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