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61.
This paper defines a Sahlqvist fragment for relevant logic and establishes that each class of frames in the Routley-Meyer semantics which is definable by a Sahlqvist formula is also elementary, that is, it coincides with the class of structures satisfying a given first order property calculable by a Sahlqvist-van Benthem algorithm. Furthermore, we show that some classes of Routley-Meyer frames definable by a relevant formula are not elementary.  相似文献   
62.
The presence of nanotechnologies grew and spread throughout Latin America during the first decade of the 21st century. Science and Technology policies have played an important role in the performance of these new technologies. Various international institutions, such as the World Bank, the Organization for Economic Co-operation and Development, and the Organization of American States promoted similar Science and Technology policies, and included nanotechnology as a priority area. This article shows the role of these Science and Technology policies in the promotion of specific objectives and the gap that was left due to the failure to incorporate an examination of the potential risks to health and environment, not to mention other labor-related effects. The omission of matters relevant to workers and consumers by these institutions led to a distancing from organized civil society.  相似文献   
63.
This paper offers an exposition of Husserl's mature philosophy of mathematics, expounded for the first time in Logische Untersuchungen and maintained without any essential change throughout the rest of his life. It is shown that Husserl's views on mathematics were strongly influenced by Riemann, and had clear affinities with the much later Bourbaki school.
Guillermo E. Rosado HaddockEmail:
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64.
The present research focuses on the design and testing of a training program in learning strategies for Mathematics in Higher Education students. This research displays a quasiexperimental-sequential design with a non-equivalent control group. The research aims at revealing the effect of this training program both on the student's competence in learning strategies and on academic performance in this curricular area. There have been 176 students taking part in this research (74 students forming the experimental group and 72 forming the control group). The obtained results permit to assess the program efficiency as regards both trained strategies handling and specific performance improvement.  相似文献   
65.
Vallejo G  Lozano LM 《Psicothema》2006,18(2):293-299
In the social, behavioral, and health researches it is a common strategy to collect data along time on more than one group of participants on multiple dependent variables. To analyse this kind of data is very complicated due to the correlations between the measures taken in different points of the time, and between the answers. Usually to analyse these data the multivariate mixed model, or the doubly multivariate model, are the most frequent approaches. Both of them require combined multivariate normality, equal covariance matrices, independence between the observations of different participants, complete measurements on all subjects, and time-independent covariates. When one ore more of these assumptions are not accomplished these approaches do not control in the correct way the Type I error, and this affects the validity and the accuracy of the inferences. In this paper some solutions that solve the problems with the error Type I will be shown. Several programs for a correct realization of the analyses through the SAS Proc Mixed procedure are presented.  相似文献   
66.
The authors assessed the joint perceptions of the employee and his or her employer to examine mutuality and reciprocity in the employment relationship. Paired psychological contract reports were obtained from 80 employee-employer dyads in 16 university-based research centers. On the basis of in-depth study of the research setting, research directors were identified as primary agents for the university (employer) in shaping the terms of employment of staff scientists (employees). By assessing the extent of consistency between employee and employer beliefs regarding their exchange agreement, the present study mapped the variation and consequences of mutuality and reciprocity in psychological contracts. Results indicate that both mutuality and reciprocity are positively related to archival indicators of research productivity and career advancement, in addition to self-reported measures of Met Expectations and intention to continue working with the employer. Implications for psychological contract theory are presented.  相似文献   
67.
Featural representations of similarity data assume that people represent stimuli in terms of a set of discrete properties. In this article, we consider the differences in featural representations that arise from making four different assumptions about how similarity is measured. Three of these similarity models— the common features model, the distinctive features model, and Tversky’s seminal contrast model—have been considered previously. The other model is new and modifies the contrast model by assuming that each individual feature only ever acts as a common or distinctive feature. Each of the four models is tested on previously examined similarity data, relating to kinship terms, and on a new data set, relating to faces. In fitting the models, we have used the geometric complexity criterion to balance the competing demands of data-fit and model complexity. The results show that both common and distinctive features are important for stimulus representation, and we argue that the modified contrast model combines these two components in a more effective and interpretable way than Tversky’s original formulation.  相似文献   
68.
Resilience refers to the process by which individuals use the ability to cope with challenges to successfully adapt to adverse situations, inclining towards the future and hope. The main aim of this study was to analyze the relation between resilience, personality traits, and hopelessness. Furthermore, we conducted comparisons between two age groups: young and older adults. The sample comprised 439 Spanish participants (66.7% women; M = 43.73, SD = 26.41; age range = 18–98 years). The Connor–Davidson Resilience Scale, NEO-Five Factor Inventory, and Beck Hopelessness Scale were used to measure the main study variables. The results revealed a negative relation between resilience and neuroticism, and a positive association with the other personality traits. Additionally, levels of resilience were found to be negatively related to hopelessness. The group of older adults showed significantly lower resilience levels than the young adults, although age was not a significant predictor of resilience. Neuroticism, extraversion, openness, and hopelessness were the only predictors of resilience for the current study. This work contributes to the study of resilience and related factors, by attempting to understand the role of resilience and resistance to risk and how individuals tackle challenges over time, with important implications for mental health.  相似文献   
69.
Amisulpride is a substituted benzamide derivative that acts as a selective dopamine D2/D3 receptor antagonist. Although the anti‐aggressive properties of neuroleptic drugs are well known, the effects of amisulpride on agonistic interactions have not been explored, and there are no studies comparing acute and subchronic effects of this compound on aggression in rodents. In this study, we examined the action of amisulpride (5–25 mg/kg, i.p), administered acutely or subchronically for 10 days, on agonistic behavior elicited by isolation in male mice. Individually housed mice were exposed to anosmic "standard opponents" 30 min after drug administration, and the encounters were videotaped and evaluated using an ethologically based analysis. After acute treatment, amisulpride (5–20 mg/kg) exhibited an ethopharmacological profile characterized by a marked decrease of offensive behaviors (threat and attack) without an impairment of motor activity. By contrast, the anti‐aggressive action of the highest dose used (25 mg/kg) was accompanied by a weak increase of immobility. Body care was also significantly enhanced after treatment with the drug (20 and 25 mg/kg), emphasizing the involvement of dopaminergic receptors in this behavior. After subchronic treatment, no tolerance to amisulpride anti‐aggressive activity was observed. Overall, this behavioral profile is similar to that observed by other atypical neuroleptics. Aggr. Behav. 25:225–232, 1999. © 1999 Wiley‐Liss, Inc.  相似文献   
70.
This study analyzed the validity of the Sherer, et al. Self-efficacy Scale for a Spanish sample of 555 subjects, 257 men and 298 women. 415 were from the general population; 34 schizophrenics and 45 with eating disorders were from a clinic, plus 61 drug addicts from two centers. All met DSM-IV-R criteria. The Eysenck Personality Questionnaire, State-Trait Anxiety Inventory, Assertiveness Inventory, and the Self-control Questionnaire were administered. The reliability for total scores, general factor were high even when social self-efficacy was low. A bidimensional factor structure seemed more acceptable. The Self-efficacy scale scores correlated with those on the Self-control Questionnaire and the Assertiveness Inventory. Extraversion scores on the Sincerity dimension of the Eysenck Personality Questionnaire correlated with scores on the State-Trait Anxiety Inventory and Eysenck's Neuroticism and Psychoticism scales. Significant mean differences appeared between the general population group and the three clinical groups. These analyses support the usefulness of the scale for clinical practice and research with Spanish samples.  相似文献   
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