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901.
Tropical forests have a high diversity of tree species which have very low densities and vary across time in their seasons of peak fruiting and maturation rates. As evidence of the ability of primates to track or anticipate changes in fruit production at individual trees, researchers have used the increased speed of primate groups toward more rewarding food patches. We analyzed the speed of approach to natural trees of wild capuchin monkeys under the effect of scramble competition, after excluding any plausible visual, olfactory and auditory cues. We conducted all-day group follows of three habituated capuchin groups at Iguazú National Park, Argentina, collecting data on ranging behavior and patterns of visits to fruit trees in relation with their location and fruit availability. Travel speed varied according to the expected reward at a feeding tree, increasing as rewards increased from low values, but decreasing again at very high values. Also, travel speed varied with time of day, decreasing from the time of first activity as the monkeys became less hungry, and increasing again toward late afternoon. Measures of unripe fruit cover did not explain variation in travel speed at any distance from a focal tree. Our data imply that, after excluding sensory cues, capuchins appear to anticipate time-varying ripe fruit quantity of natural resources, suggesting that they use memory of tree location and anticipation of fruit maturation. We also confirm that speed is a good measure about expectations of resources, as has been shown in previous studies.  相似文献   
902.
Two sources of information most relevant to guide social decision making are the cooperative tendencies associated with different people and their facial emotional displays. This electrophysiological experiment aimed to study how the use of personal identity and emotional expressions as cues impacts different stages of face processing and their potential isolated or interactive processing. Participants played a modified trust game with 8 different alleged partners, and in separate blocks either the identity or the emotions carried information regarding potential trial outcomes (win or loss). Behaviorally, participants were faster to make decisions based on identity compared to emotional expressions. Also, ignored (nonpredictive) emotions interfered with decisions based on identity in trials where these sources of information conflicted. Electrophysiological results showed that expectations based on emotions modulated processing earlier in time than those based on identity. Whereas emotion modulated the central N1 and VPP potentials, identity judgments heightened the amplitude of the N2 and P3b. In addition, the conflict that ignored emotions generated was reflected on the N170 and P3b potentials. Overall, our results indicate that using identity or emotional cues to predict cooperation tendencies recruits dissociable neural circuits from an early point in time, and that both sources of information generate early and late interactive patterns.  相似文献   
903.
Previous research has shown the impact of the emotional dimension of nouns (i.e., valence and arousal) on the completion of relative clauses (RC) that are preceded by a double antecedent [e.g.,: Someone shot the servant (the first noun phrase, NP1) of the actress (the second noun phrase, NP2) who was on the balcony] (Fraga et al. in Q J Exp Psychol 65:1740–1759, 2012). The present study explored for the first time the role of emotional valence, specifically emotional positive nouns, on RC disambiguation in a self-paced reading experiment. Two types of NP1–NP2 relationships were compared: emotional–neutral vs. neutral–emotional. Results showed NP1 preferences in the emotional–neutral condition, whereas no preferences were found in the neutral–emotional condition. We conclude that during reading, the emotional properties of nouns play a role in disambiguation preferences: RC attachment preferences can be neutralized when emotional factors are manipulated. The results are discussed within the framework of current models of sentence processing and with reference to the controversial differences between comprehension and production.  相似文献   
904.
Background/Objectives: Motivational Enhancement Treatment in Spanish (METS) is a brief intervention aimed at resolving patient ambivalence towards behavior change that has demonstrated efficacy in substance use disorder treatment to reduce use and increase treatment engagement in different populations. In order to have evidence for its implementation in Mexico, a multi-site, randomized, two-arm, controlled clinical trial was conducted at three outpatient addiction treatment centers in the country to compare the effect of METS with Counseling as Usual (CAU). Method: One hundred and twenty patients were randomized to receive three sessions of METS (n = 54) or CAU (n = 66) during the first four weeks of treatment and were assessed during the following 12 weeks. Primary outcome measures were self-reported days of substance use and of treatment services utilization, which were tested using Generalized Estimating Equations. Results: Results associated both conditions with significant changes in substance use over, whereas there were no differences between conditions in substance use or in service utilization. Conclusions: Findings do not support the hypothesis that METS is more effective than CAU, but suggest that brief interventions at treatment initiation may improve patient outcomes.  相似文献   
905.

Background/Objective

Despite the growing interest in the study of dating violence, relatively few psychometrically sound instruments are available to researchers. To provide an instrument to researchers and professionals to assess victimization in dating relationships, with adequate psychometric properties. Method: Participants were 6,138 adolescents drawn from the general population, 25% of which were university students. Participants responded to the original Dating Violence Questionnaire (DVQ). Results: Confirmatory analyses results provided evidence of a clear factorial structure that was invariant through sex groups. The DVQ-R measures with 20 items five dimensions of abuse in affective interpersonal relationships of adolescents and youth: Detachment, Humiliation, Coercion, Physical and Sexual violence. Internal consistency indexes were adequate for both each one of the five dimensions as well as for the general scale. Conclusions: The DVQ-R is an useful assessment to be applied in adolescents and youth. Implications for research and intervention are discussed in light of the results obtained.  相似文献   
906.
907.
The present research evaluates how people integrate factual ‘if then’ and semifactual ‘even if’ conditional premises in an inference task. The theory of mental models establishes that semifactual statements are represented by two mental models with different epistemic status: ‘A & B’ is conjectured and ‘not-A & B’ is presupposed. However, following the principle of cognitive economy in tasks with a high working memory load such as reasoning with multiple conditionals, people could simplify the deduction process in two ways, by discarding: (a) the presupposed case and/or (b) the epistemic status information. In Experiment 1 and Experiment 2, we evaluated each of these hypotheses. In Experiment 1, participants make inferences from two conditionals: two factual conditionals or one factual and one semifactual, with different representations. In Experiment 2, participants make inferences with a factual conditional followed by two different semifactual conditionals that share the same representations but differ in their epistemic status. Accuracy and latency data suggest that people think of both the conjectured and the presupposed situations, but do not codify the epistemic status of either when the task does not require it. The results are discussed through theoretical predictions about how people make inferences from different connected conditionals.  相似文献   
908.
The aim of this study was to develop and validate the Satisfaction in Couple Relationship Scale (SCR) in order to provide a tool that is clear and useful for research and professional practice with couples. The sample was made up of 620 participants in a couple relationship (57.7% women and 42.3% men). Most of participants were aged 32 or older (51.6%), were not married (54%), lived with their partner (66.1%) and did not have children (57.9%). The sample was randomly divided in two subsamples in order to study the factor structure or construct validity; a cross-validation strategy was used consisting of an exploratory factor analysis (EFA) on the first one, and a confirmatory factor analysis (CFA) on the second one. Findings resulted in a 10-items scale made up of a single factor that explained 54.14% of the variance, and had excellent internal consistency reliability (α?=?0.93).  相似文献   
909.
910.
A nearly abrupt coarsening of grains is observed in a newly developed FeAlO ultra-fine-grained nanocomposite with a significant volume fraction (4%) of alumina nano-precipitates. The microstructure of the alloy was analysed in different states (as-received and annealed) by means of scanning electron microscopy, transmission electron microscopy (TEM) and hardness. The initial grain size 150–200 nm increases up to 50 μm during annealing 1000 °C/8 h and thereafter demonstrates saturation. A linear correlation between volume fraction of coarse grains and hardness was found. It was identified by TEM that alumina nano-precipitates stabilize the dislocation microstructure against recovery very effectively and the grain coarsening is due to fast growth of very few dislocation free grains. Thus, the observed grain coarsening has the attributes of static recrystallization.  相似文献   
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