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31.
Consider two standard quantified modal languages \(\textbf{\textsf{A}}\) and \(\textbf{\textsf{P}}\) whose vocabularies comprise the identity predicate and the existence predicate, each endowed with a standard S5 Kripke semantics where the models have a distinguished actual world, which differ only in that the quantifiers of \(\textbf{\textsf{A}}\) are actualist while those of \(\textbf{\textsf{P}}\) are possibilist. Is it possible to enrich these languages in the same manner, in a non-trivial way, so that the two resulting languages are equally expressive—i.e., so that for each sentence of one language there is a sentence of the other language such that given any model, the former sentence is true at the actual world of the model iff the latter is? Forbes (1989) shows that this can be done by adding to both languages a pair of sentential operators called Vlach-operators, and imposing a syntactic restriction on their occurrences in formulas. As Forbes himself recognizes, this restriction is somewhat artificial. The first result I establish in this paper is that one gets sameness of expressivity by introducing infinitely many distinct pairs of indexed Vlach-operators. I then study the effect of adding to our enriched modal languages a rigid actuality operator. Finally, I discuss another means of enriching both languages which makes them expressively equivalent, one that exploits devices introduced in Peacocke (1978). Forbes himself mentions that option but does not prove that the resulting languages are equally expressive. I do, and I also compare the Peacockian and the Vlachian methods. In due course, I introduce an alternative notion of expressivity and I compare the Peacockian and the Vlachian languages in terms of that other notion.  相似文献   
32.
The neurosteroid dehydroepiandrosterone (DHEA) is a powerful inhibitor of aggression in murine models when given for 15 days and potentially may be useful in the management of inappropriate human aggression. Although the biosynthesis and metabolism of DHEA have been described, little is known about the potential effect of the steroidal environment during sexual differentiation on the subsequent response to DHEA. Whether prenatal androgen exposure influences the subsequent response to DHEA was assessed by comparing the effect of DHEA (80 μg/d) on aggression in female offspring where dams were treated with 1, 10, or 100 μg of testosterone (T) on days 15 to 18 of gestation (Experiment I) or that developed in different uterine positions (Experiment II). The results showed that DHEA decreased attack behavior in general and that the 100‐μg prenatal T treatments enhanced the antiaggressive effect of this neurosteroid. Neither the lower doses of exogenously administered T nor the uterine position led to an enhanced response to DHEA. In addition, whether DHEA produced changes in social and nonsocial activities was examined. In the 100‐μg T females, DHEA increased the duration of the former and decreased the frequency and duration of the latter, indicating that it was not a general decrement in behavioral expression that mediated the enhanced response to the antiaggressive effect of DHEA. In the second experiment, DHEA treatment led to increased frequencies of social nonaggressive and nonsocial activities. However, the uterine positions × treatment interactions were not significant, demonstrating that contiguity to male fetuses did not differentially affect the response to DHEA. Aggr. Behav. 27:130–138, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
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Latencies for intrusion upon same- and different-sex dyads in a university dining hall were Investigated. Latencies were longer for different-sex dyads than for either of the male-male and female-female dyads. No significant differences were revealed between the two types of same-sex dyads. The results were explained by the assumption of greater affective interdependence for mixed-sex than same-sex dyads.  相似文献   
35.
The use of Intelligent Assistive Technology (IAT) in dementia care opens the prospects of reducing the global burden of dementia and enabling novel opportunities to improve the lives of dementia patients. However, with current adoption rates being reportedly low, the potential of IATs might remain under-expressed as long as the reasons for suboptimal adoption remain unaddressed. Among these, ethical and social considerations are critical. This article reviews the spectrum of IATs for dementia and investigates the prevalence of ethical considerations in the design of current IATs. Our screening shows that a significant portion of current IATs is designed in the absence of explicit ethical considerations. These results suggest that the lack of ethical consideration might be a codeterminant of current structural limitations in the translation of IATs from designing labs to bedside. Based on these data, we call for a coordinated effort to proactively incorporate ethical considerations early in the design and development of new products.  相似文献   
36.
The main objective of this study is to settle a rigorous field of decision analysis for rubber tree clones selection. Nowadays, there does not exist any process based upon a rigorous method to select the best clone to be plant in order to get the highest return on investment. The only known selection method is to use the experience of different protagonists acting in the plantation. So, we need a tool that takes into account very important criteria in order to achieve the main objective. This goal is achieved by using multicriterion analysis methods to the clone selection. The ranking procedure uses Elimination and Choice Expressing the Reality (ELECTRE III). For each criterion, indifference and preference thresholds are determined after establishing the relative importance of each criterion including rubber tapping, cumulative production during 15 years, cumulative production between 15 and 25 years, wind resistance, disease resistance, physiological resistance, grafting and quality of the rubber. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
37.
This study examined the role of stimulus characteristics in a visuospatial order reconstruction task in which participants were required to recall the order of sequences of spatial locations. The complexity of the to-be-remembered sequences, as measured by path crossing, path length, and angles, was found to affect serial memory, in terms of both recall accuracy and response times. The results demonstrate that not all sequences are remembered equally and that spatial characteristics of the sequences constitute an important variable in the understanding of visuospatial serial memory. More important, the data suggest that spatial path represents transitional information and that, as is the case in verbal serial memory, transitional information is of critical importance in serial memory.  相似文献   
38.
The influence of a family history of suicide on suicide attempt rate and characteristics in depression, schizophrenia, and opioid dependence was examined. One hundred sixty inpatients with unipolar depression, 160 inpatients with schizophrenia, and 160 opioid-dependent patients were interviewed. Overall, a family history of suicide was associated with a higher risk for suicide attempt, with high-lethality method, with repeated attempts, and with number of attempts, while the interaction between family history and diagnostic group was not significant. Thus, a positive family history of suicide was a risk factor for several suicide attempt characteristics independent of psychiatric diagnosis.  相似文献   
39.
The extent to which young children monitor and use the truth of assertions to gauge the reliability of subsequent testimony was examined. Three- and 4-year-old children were presented with two informants, an accurate labeler and an inaccurate labeler. They were then invited to learn names for novel objects from these informants. The children correctly monitored and identified the informants on the basis of the truth of their prior labeling. Furthermore, children who explicitly identified the unreliable or reliable informant across two tasks went on to demonstrate selective trust in the novel information provided by the previously reliable informant. Children who did not consistently identify the unreliable or reliable informant proved indiscriminate.  相似文献   
40.
Grouping effects in serial recall have been widely studied with verbal stimuli, but hardly ever with spatial stimuli and not at all with auditory spatial stimuli. In Experiment 1, we examined the influence of combined temporal and pitch grouping on recall of the locations from which bursts of white noise were presented. Similar to findings in verbal studies, effects of the grouping manipulation were found in performance accuracy, in the nature of order errors, and in the timing of responses. Experiment 2 was designed to distinguish the role played by pitch grouping from that played by temporal grouping, through independent manipulation of the presence of a shift in pitch and that of a temporal gap. The results showed that the temporal grouping manipulation determined performance and the pitch grouping manipulation did not. Similarities between our findings and those of verbal studies, and implications for the understanding of serial memory are discussed.  相似文献   
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