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1.
2-Deoxy-d-galactose (do-gal) hinders glycoprotein fucosylation. This compound was intracerebroventricularly administered to male adult Wistar rats in order to assess whether it could exert amnesic effects on a passive avoidance response (PAR) to be learned in the light–dark box apparatus. Three experiments were performed. In the first, do-gal was administered immediately after the acquisition trials at three dosages (2, 4, and 8 μmol). It was found that only the 4-μmol dosage was followed by PAR disruption. In the second, do-gal was administered at the adequate dosage (4 μmol) either 30 min before the acquisition trial or 30 min before retrieval testing. It was found that only the preretrieval administration was followed by PAR impairment. In the third, do-gal (4 μmol) was administered in postacquisition, at increasing postacquisition delays (0.25, 1.5, 4, and 6 h). It was found that there was PAR disruption only after do-gal administration at the shortest (0.25 h) delay. The results confirm that in the rat, glycoprotein fucosylation is involved in some of the phases of memory trace processing, and they are discussed in relation to other findings in the rat and the chick.  相似文献   
2.
Contemporary optimization models suggest that animals optimize benefits of foraging and minimize its costs. For wild bearded capuchins (Sapajus libidinosus), nut-cracking entails cost related to lifting the heavy stone and striking the nut and additional cost to transport the stone if it is not already on the anvil. To assess the role of stone mass and transport distance in capuchins’ tool selection, we carried out three field experiments. In Experiment 1, we investigated whether transport distance affected choice of a tool by positioning two stones of the same mass close and far from the anvil. Capuchins consistently selected the closer stone, effectively reducing transport costs. In Experiment 2, we examined the trade-off between the cost of transport and the effectiveness in cracking by positioning two stones of different mass close and far from the anvil. Most subjects significantly preferred the closer stone, regardless of mass, whereas others preferred the heavier stone regardless of transport distance. In Experiment 3, we changed transport distance of both stones while maintaining the same distance ratios as in Experiment 2. Capuchins maintained the preferences expressed in Experiment 2, with the exception of one subject. Overall, our findings indicate that (1) individuals vary in their sensitivity to distance of transport, (2) a few meters are perceived as a substantive cost by some monkeys, and (3) monkeys’ body mass affects their decisions. We also developed a non-dimensional Preference index (P) defined as a function of the stone mass and the transport distance to describe monkey’s choice.  相似文献   
3.
We examined whether eight capuchins and eight chimpanzees were able to retrieve a reward placed inside a tube, of varying length, by selecting the correct stick from different sets of three sticks differing in length (functional feature) and handle (non-functional feature). Moreover, to investigate whether seeing the stick inside the tube (visual feedback) improves performance, half of the subjects were tested with a transparent apparatus and the other half with an opaque apparatus. Phase 1 included (a) Training 1 in which each stick had a different handle and (b) Transfer 1 in which the handles were switched among sticks, so that the functional tool had the same length but a different handle than before. The seven chimpanzees and one capuchin that passed Transfer 1 received Transfer 2. The other subjects received (a) Training 2, which used the same sticks from Phase 1 with handles switched in every trial, and (b) Transfer 2 in which the tube was longer, all sticks had the same new handle, and the formerly longest tool became intermediate in length. Eight chimpanzees and three capuchins passed Transfer 2. Results showed that (1) chimpanzees applied relational structures in tool using tasks more quickly than capuchins and (2) capuchins required more varied experience to attend to the functional feature of the tool. Interestingly, visual feedback did not improve performance in either species.  相似文献   
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5.
Peaceful third‐party interventions usually occur after an aggressive encounter and can be directed toward the victim or the aggressor. Macaca tonkeana, a cercopithecine species characterized by high levels of tolerance, frequently engage in consolatory contacts, which both calm the victim and reduce the probability of further attacks against him/her. Other post‐conflict affiliative interventions such as reconciliation and quadratic affiliation are also common in this species. However, little attention has been given to contacts directed toward the aggressor. Here, we explore the role of bystander affiliative interventions toward the aggressor in influencing the affective state of the aggressor and the consequences of triadic interventions at group level. We found that triadic post‐conflict affiliation occurred independently from the intensity of the conflict and that it was more frequent in absence of the conciliatory contact between the opponents (reconciliation). Bystanders showed a higher amount of post‐conflict affiliation toward low ranking aggressors. Post‐conflict triadic affiliation functioned as a tension reduction mechanism by lowering the arousal of the aggressor, which less frequently engaged in renewed aggression. All these findings suggest that post‐conflict triadic contacts in Tonkean macaques can be considered as a strategic mechanism to calm the aggressor and reduce the risk of retaliatory aggression.
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6.
Abstract

This study examines the relation between educational and vocational identity in Romanian adolescents. Access to work-relevant experiences is very limited among Romanian adolescents, and most encounters with career constructs are confined to educational settings. Hence, to gain a better understanding of how identity processes in the educational and vocational domains support or inhibit each other, we aimed at investigating: (a) educational and vocational identity statuses through cluster analysis and (b) associations between identity statuses in these life domains. Participants were 1551 Romanian youth, aged 14–20 (39.3% girls), who completed measures of educational and vocational identity. Results indicated that, in the Romanian context, educational and vocational identities are closely linked, as adolescents draw information for future career development mostly from their educational experiences. Implications for youth policies and for applied interventions sensitive to socioeconomic and cultural realities are discussed.  相似文献   
7.
We studied economic choice behavior in capuchin monkeys by offering them to choose between two different foods available in variable amounts. When monkeys selected between familiar foods, their choice patterns were well-described in terms of relative value of the two foods. A leading view in economics and biology is that such behavior results from stimulus-response associations acquired through experience. According to this view, values are not psychologically real; they can only be defined a posteriori. One prediction of this associative model is that animals faced for the first time with a new pair of foods learn to choose between them gradually. We tested this prediction. Surprisingly, we find that monkeys choose as effectively between new pairs of foods as they choose between familiar pairs of foods. We therefore, propose a cognitive model in which economic choice results from a two-stage mental process of value-assignment and decision-making. In a follow-up experiment, we find that the relative value assigned to three foods in sessions in which we tested them against each other combine according to transitivity.  相似文献   
8.
Lalumera  Elisabetta  Fanti  Stefano 《Topoi》2019,38(2):395-400
Topoi - We raise a problem of applicability of RCTs to validate nuclear diagnostic imaging tests. In spite of the wide application of PET and other similar techniques that use radiopharmaceuticals...  相似文献   
9.
As the impact of breast cancer (BC) risk assessment in asymptomatic women with a family history of BC had never been explored in Italy, we performed a study on a retrospective series of women who had undergone BC risk assessment. To this aim, a semi-structured telephone interview was administered to 82 women. Most participants considered the information received as clear (96.2 %) and helpful (76.8 %). Thirty-eight (46.3 %) stated that their perceived risk of BC had changed after the counseling: for 40.2 % it had decreased, for 6.1 % increased; however, women highly overestimating their risk at the baseline (≥4-fold) failed to show improvements in risk perception accuracy. Sixty-six women (80.5 %) stated they had followed the recommended surveillance, while 19.5 % had not, mainly due to difficulties in arranging examinations. Most women (89.0 %) had shared the information with their relatives, with 57.3 % reporting other family members had undertaken the recommended surveillance. BC risk assessment was associated with high rates of satisfaction and had a favorable impact on risk perception in a subgroup of women. The impact on surveillance adhesion extended to relatives. Organized programs for identification and surveillance may help identify a larger fraction of at-risk women and overcome the reported difficulties in arranging surveillance.  相似文献   
10.
Background and Objectives: Social anxiety symptoms and delinquency are two prevalent manifestations of problem behavior during adolescence and both are related to negative interpersonal relationships in adolescence and emerging adulthood. This study examined the relation between social anxiety and delinquency in adolescence and the interplay between adolescent social anxiety and delinquency on perceived relationship quality in emerging adulthood. Design and Methods: In a 10-year long prospective study (T1, n = 923; T2, n = 727; Mage T1 = 12; 49% female), we examined competing hypotheses using regression analyses: the protective perspective, which suggests social anxiety protects against delinquency; and the co-occurring perspective, which suggests social anxiety and delinquency co-occur leading to increased negative interpersonal outcomes. Results: In adolescence, the relation between social anxiety and delinquency was consistent with the protective perspective. In emerging adulthood, consistent with the co-occurring perspective, ever-delinquents (but not delinquency abstainers) with higher social anxiety reported less perceived best friend, mother, and father support compared to delinquents with lower social anxiety. There was no interaction between anxiety and delinquency in predicting perceived conflict. Conclusion: This study highlights the importance of examining the relation between social anxiety and delinquency with regards to different interpersonal outcomes.  相似文献   
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