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91.
This study examined the dimensional structure of Tomás-Sábado and Gómez-Benito's Death Anxiety Inventory and Templer, et al.'s Death Depression Scale-Revised. The responses of 244 Spanish nurses to the Spanish forms of both scales were evaluated by means of a principal axis factor analysis with direct Oblimin rotation. Five significant factors were identified: Internally Generated Death Anxiety, Death Depression, Externally Generated Death Anxiety, Death Threat, and Death Sadness, accounting for 51.6% of the variance. The distribution of the factor loadings for the items of both scales on the five factors supported the discriminant validity of the constructs specific to each of the scales and justified their use in evaluating death anxiety and death depression independently.  相似文献   
92.
In this paper we present the syntax and semantics of a temporal action language named Alan, which was designed to model interactive multimedia presentations where the Markov property does not always hold. In general, Alan allows the specification of systems where the future state of the world depends not only on the current state, but also on the past states of the world. To the best of our knowledge, Alan is the first action language which incorporates causality with temporal formulas. In the process of defining the effect of actions we define the closure with respect to a path rather than to a state, and show that the non-Markovian model is an extension of the traditional Markovian model. Finally, we establish relationship between theories of Alan and logic programs.  相似文献   
93.
The purpose of this paper is to examine the effectiveness of Reconnecting Youth, a prevention program for at-risk high school youth. Data are from a large, independently evaluated effectiveness trial in two diverse urban school districts. A total of 1,218 students participated; 50% were male; average age was 15. We tested whether positive efficacy trial effects could be replicated, and whether any negative behavioral effects occur when clustering high-risk youth. Although mixed program effects were observed at immediate post-intervention, only negative effects were found at 6-month follow-up. These effects included less optimal scores on measures of GPA, Anger, School Connectedness, Conventional Peer Bonding, and Peer High-Risk Behaviors. Overall, we found little support for the use of this social-influence—model intervention aimed at increasing school connectedness for high-risk youth. Further, this study provides evidence that clustering high-risk youth in preventive interventions has the potential for iatrogenic effects.  相似文献   
94.
Previous studies have suggested that nonnative (L2) linguistic sounds are accommodated to native language (L1) phonemic categories. However, this conclusion may be compromised by the use of explicit discrimination tests. The present study provides an implicit measure of L2 phoneme discrimination in early bilinguals (Catalan and Spanish). Participants classified the 1st syllable of disyllabic stimuli embedded in lists where the 2nd, task-irrelevant, syllable could contain a Catalan contrastive variation (/epsilon/-/e/) or no variation. Catalan dominants responded more slowly in lists where the 2nd syllable could vary from trial to trial, suggesting an indirect effect of the /epsilon/-/e/ discrimination. Spanish dominants did not suffer this interference, performing indistinguishably from Spanish monolinguals. The present findings provide implicit evidence that even proficient bilinguals categorize L2 sounds according to their L1 representations.  相似文献   
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Human infants use prosodic cues present in speech to extract language regularities, and it has been suggested that this capacity is anchored in more general mechanisms that are shared across mammals. This study explores the extent to which rats can generalize prosodic cues that have been extracted from a training corpus to new sentences and how this discrimination process is affected by the normalization of the sentences when multiple speakers are introduced. Conditions 1 and 2 show rats' abilities to use prosodic cues present in speech, allowing them to discriminate between sentences not previously heard. But this discrimination is not possible when sentences are played backward. Conditions 3 and 4 show that language discrimination by rats is also taxed by the process of speaker normalization. These findings have remarkable parallels with data from human adults, human newborns, and cotton-top tamarins. Implications for speech perception by humans are discussed.  相似文献   
98.
The authors investigated whether human listeners could categorize played-back dog (Canis familiaris) barks recorded in various situations and associate them with emotional ratings. Prerecorded barks of a Hungarian herding dog breed (Mudi) provided the sample. Human listeners were asked to rate emotionality of the vocalization and to categorize the situations on the basis of alternative situations provided on a questionnaire. The authors found almost no effect of previous experience with the given dog breed or of owning a dog. Listeners were able to categorize bark situations high above chance level. Emotionality ratings for particular bark samples correlated with peak and fundamental frequency and interbark intervals. The authors did not find a significant effect of tonality (harmonic-to-noise ratio) on either the emotionality rating or situation categorization of the human listeners. Humans' ability to recognize meaning suggests that barks could serve as an effective means of communication between dog and human.  相似文献   
99.
Research that uses simple response time tasks and neuroimaging has emphasized that attentional preparation based on temporal expectancy modulates processing at motor levels. A novel approach was taken to study whether the temporal orienting of attention can also modulate perceptual processing. A temporal-cuing paradigm was used together with a rapid serial visual presentation procedure, in order to maximize the processing demands of perceptual analysis. Signal detection theory was applied in order to examine whether temporal orienting affects processes related to perceptual sensitivity or to response criterion (indexed byďand beta measures, respectively). If temporal orienting implies perceptual preparation, we would expect to observe an increase in perceptual sensitivity (ď) when a target appeared at expected, rather than unexpected, time intervals. Indeed, our behavioral results opened the possibility that focusing attention on time intervals not only enhances motor processing, as has been shown by previous research, but also might improve perceptual processing.  相似文献   
100.
Both the acquisition and the extinction of memories leave short- and long-term mnemonic traces. Here, we show that in male Wistar rats, the short-term memory for a step-down inhibitory avoidance task (IA) is resistant to extinction, and that its expression does not influence retrieval or extinction of long-term memory. It has been known for some time that short- and long-term inhibitory avoidance memory involve separate and parallel processes. Here we show that, instead, short-term extinction of IA long-term memory is the first step towards its long-term extinction, and that this link requires functional NMDA receptors and protein synthesis in the CA1 region of the dorsal hippocampus at the time of the first CS-no US presentation.  相似文献   
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