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A first step towards the improvement of daily dietary behaviors is forming an intention to change one's nutrition. However, an intention by itself is not sufficient for successful action. Rather, to translate intentions into behavior, careful planning is recommended. Thus, planning constitutes a mediator between the intention and the behavior. However, if a person lacks self-efficacy, this mediation might fail. Previous research in Costa Rica and South Korea has identified perceived self-efficacy as a moderator of the intention-planning-behavior relationship. To examine further the moderator role of self-efficacy, two additional studies were designed in Thailand and Germany. Study 1 surveyed 1718 Thai university students in terms of a low-fat diet; Study 2 surveyed 1140 German internet users in terms of their fruit and vegetable consumption at two measurement points in time, 6 months apart. Intentions served as predictor, planning as mediator, self-efficacy as moderator, and behaviors as outcomes. First, intentions were translated into nutrition behaviors by planning. Second, self-efficacy moderated this mediation in both studies: The strength of the mediated effect increased along with levels of self-efficacy, even when accounting for baseline behaviors. For planning to mediate the intention-behavior relation, people must not harbor self-doubts. If they lack self-efficacy, intentions are not well translated into nutrition behavior through planning.  相似文献   
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It is known that the binary Cu–2?wt.% Be alloy can be strengthened by ageing its supersaturated solution at 523?K. The increase in the strength arising from ageing is because of the formation of GP zones. The same level of strength is achieved by ageing the supersaturated solid solution of a dilute binary Cu–4?wt.% Ti alloy at 723?K. In contrast to Cu–2?wt.% Be alloy, the increase in strength in this alloy occurs on account of spinodal decomposition of the as-quenched microstructure through the mechanism of clustering and ordering. In the present study, decomposition of a supersaturated solid solution of the ternary Cu–4?wt.% Ti–2?wt.% Be alloy was studied. Whereas ageing of this alloy at 523?K resulted in the formation of GP zones like in a Cu–2?wt.% Be alloy, ageing at 723?K resulted in a spinodally decomposed microstructure as in a Cu–4?wt.% Ti alloy. The decomposition of the ternary alloy at the two temperatures by two different mechanisms indicates that Be and Ti in solution in Cu act, more or less, independently of each other during ageing.  相似文献   
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What distinguishes photography from other visual mediums? This deceptively simple but fundamental question has been at the centre of both past and current debates on the aesthetics of photography for quite some time. In this article, I will first address the premise that this question is intrinsically ontological and unfolded in pioneering debates as a sequence of implications about photographic indexicality. I will then argue that the ontological implications of photographic indexicality have been largely overlooked in subsequent research due to scholars’ concerns with how photography appears to us rather than what photography is in itself. To this end, I will specifically examine Kendall Walton's highly contested transparency thesis and some of its rebuttals, which have exerted a sprawling influence on debates on the aesthetics of photography. I will also argue that, having been exceedingly implicit in his account, what appears as indexicality to Walton and the implications thereof with respect to the transparency argument has operated on a phenomenological level; thus, the thesis itself has failed in instances in which the problem of representation and the very existence of the medium come into play. Finally, I will suggest that indexicality can be regarded as a distinctive feature of photography only when it is considered a predicate of transparency as an interstice of ‘unconcealment’ in the Heideggerian sense that would call into question the very existence of the representation and the photographic medium.  相似文献   
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Intertemporal tradeoffs are ubiquitous in decision making, yet preferences for current versus future losses are rarely explored in empirical research. Whereas rational‐economic theory posits that neither outcome sign (gains vs. losses) nor outcome magnitude (small vs. large) should affect delay discount rates, both do, and moreover, they interact: in three studies, we show that whereas large gains are discounted less than small gains, large losses are discounted more than small losses. This interaction can be understood through a reconceptualization of fixed‐cost present bias, which has traditionally described a psychological preference for immediate rewards. First, our results establish present bias for losses—a psychological preference to have losses over with now. Present bias thus predicts increased discounting of future gains but decreased (or even negative) discounting of future losses. Second, because present bias preferences do not scale with the magnitude of possible gains or losses, they play a larger role, relative to other motivations for discounting, for small magnitude intertemporal decisions than for large magnitude intertemporal decisions. Present bias thus predicts less discounting of large gains than small gains but more discounting of large losses than small losses. The present research is the first to demonstrate that the effect of outcome magnitude on discount rates may be opposite for gains and losses and also the first to offer a theory (an extension of present bias) and process data to explain this interaction. The results suggest that policy efforts to encourage future‐oriented choices should frame outcomes as large gains or small losses. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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We have fabricated a molecular organic light-emitting device comprising indium–tin oxide/a molecular organic layer/aluminum in which the organic layer is a green fluorescent protein. The device exhibits peak external quantum and power efficiencies of 8?±?0.2% and 13?±?0.7?lm?W???1 at a current of J?=?1.5?A?m?2, respectively. In addition, the turn-on voltage is 2.5?V for 1?cd?m?2 and the maximum luminance achieved is 1275?cd?m?2. This good performance can be explained by the presence of singlet-excited states, leading to a high internal efficiency.  相似文献   
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