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21.
Twelve rats made repeated choices on an adjusting-delay schedule between a smaller reinforcer (A) that was delivered immediately after a response and a larger reinforcer (B) that was delivered after a delay which increased or decreased by 20% depending on the subject's choices in successive blocks of trials. In two phases of the experiment (100 sessions and 40 sessions), reinforcer sizes were selected which enabled theoretical parameters expressing the rate of delay discounting and sensitivity to reinforcer size to be estimated from the ratio of the indifference delays obtained in the two phases. Indifference delays, calculated from adjusting delays in the last 10 sessions of each phase, were shorter when the sizes of A and B were 14 and 25 μl of a 0.6 M sucrose solution than when they were 25 and 100 μl of the same solution. The ratio of the indifference delays was significantly smaller than that predicted on the basis of an assumed linear relation between reinforcer size and instantaneous reinforcer value, consistent with a previous proposal that this relation may be hyperbolic in form. Estimates of the rate of delay discounting based on the ratio of the two indifference delays (mean, 0.08 s(-1)) were similar to values obtained previously using different intertemporal choice protocols. Estimates of the size-sensitivity parameter (mean 113 μl) were similar to estimates recently derived from performance on progressive-ratio schedules. In both phases of the experiment, adjusting delays in successive blocks of trials were analyzed using the Fourier transform. The power spectrum obtained from individual rats had a dominant frequency that corresponded to a period of oscillation of the adjusting delay between 30 and 100 trial blocks (mean, 78). Power in the dominant frequency band was highest in the early sessions of the first phase and declined with extended training. It is suggested that this experimental protocol may have utility in neurobehavioral studies of intertemporal choice.  相似文献   
22.
The literature on quantum logic emphasizes that the algebraic structures involved with orthodox quantum mechanics are non distributive. In this paper we develop a particular algebraic structure, the quasi-lattice ( \mathfrakI{\mathfrak{I}}-lattice), which can be modeled by an algebraic structure built in quasi-set theory \mathfrakQ{\mathfrak{Q}} . This structure is non distributive and involve indiscernible elements. Thus we show that in taking into account indiscernibility as a primitive concept, the quasi-lattice that ‘naturally’ arises is non distributive.  相似文献   
23.
Here, we report an investigation of the patterned movement behavior of players for a specific sub-phase of the game of futsal, namely when the goalkeeper for the attacking team is substituted with an extra outfield player. The movement trajectories of the ball and players were recorded in both lateral and longitudinal directions and investigated using relative phase analysis. Some differences in phase relations between different playing dyads were noted, indicating specificity of phase attractions, or otherwise, for certain players. In general terms, the defenders demonstrated strong in-phase attractions with the ball and with each other, whereas weaker phase attractions, indicated by increased relative phase variability, were observed for the attackers and ball, as well as between attackers themselves. These results demonstrate different coordination dynamics for the defending and attacking dyads, from which we interpret evidence for different playing sub-systems consistent with different team objectives linked together in an overarching game structure. In keeping with dynamical systems theory for complex systems, we view this sub-phase of futsal as being characterized by coordinated behavior patterns that emerge as a result of self-organizing processes. These dynamic patterns are generated within functional constraints, with players and teams exerting mutual influence on each other.  相似文献   
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This paper tests the efficacy of an intervention program in virtual format intended to train studying and self-regulation strategies in university students. The aim of this intervention is to promote a series of strategies which allow students to manage their learning processes in a more proficient and autonomous way. The program has been developed in Moodle format and hosted by the Virtual Campus of the University of Oviedo. The present study had a semi-experimental design, included an experimental group (n=167) and a control one (n=206), and used pretest and posttest measures (self-regulated learning strategies' declarative knowledge, self-regulated learning macro-strategy planning-execution-assessment, self-regulated learning strategies on text, surface and deep learning approaches, and academic achievement). Data suggest that the students enrolled in the training program, comparing with students in the control group, showed a significant improvement in their declarative knowledge, general and on text use of learning strategies, increased their deep approach to learning, decreased their use of a surface approach and, in what concerns to academic achievement, statistically significant differences have been found in favour of the experimental group.  相似文献   
26.
We present a study that investigates changes in the acquisition and development of morphological awareness in children from 5 to 7 years old. This investigation was carried out on three separate occasions over two academic years, in which morphological awareness was assessed according to two levels. The data indicate an increase in the morphological awareness development from the kindergarten to primary education, verifying the acquisition in the first instance of the morphological judgment level and secondly, of morphological production level. It also generates a pattern of acquisition of the various parameters that make up morphology.  相似文献   
27.
About 10 % of infertile/subfertile women are diagnosed with diminished ovarian reserve (DOR), of which?<?5 % will become pregnant spontaneously. Fragile X (FMR1) genetic testing may provide a reason for her early ovarian aging and/or have reproductive implications. Seven women with DOR (genetic study subset) and the male partners of six of these women were separately interviewed about the experience of being asked to undergo this unanticipated genetic test. Three interviews were conducted (before, within 1 week after, and 3 months after learning the test results). None of the participants carried the FMR1 premutation (largest FMR1 allele 27–50 CGG repeats). For women, their pregnancy-seeking journey was long and exhausting. Women understood the reproductive implications of carrying the FMR1 premutation, and hoped for a negative result. Being offered a genetic test caused women to pause and re-think their future reproductive plans. Husbands viewed the infertility journey as filled with unknowns, of which the genetic test results would be one more puzzle piece. The expense of fertility testing/treatment was mentioned by both spouses, though more notably by husbands. The introduction of a possible genetic cause of infertility, with additional potential health consequences for future biological children, caused women to re-think their quest for pregnancy. In contrast, the genetic test was viewed as an additional source of information for their husbands as opposed to raising concern regarding potential reproductive ramifications.  相似文献   
28.
Parenting practices should be assessed and taken into account at an early age, since it is well documented that they are strongly related to children’s development. This study provides data on the psychometric properties of a Spanish version of the Alabama Parenting Questionnaire for Preschool children (APQ-Pr). A community sample of 622 (310 boys and 312 girls) 3 year-old children and their parents, participated in the study. Data were obtained from parents’ reports and correspond to a semi-structured diagnostic interview and self-report questionnaires evaluating parenting and children’s psychological states. Confirmatory factor analysis supported a three-factor solution: positive parenting, inconsistent parenting and punitive parenting. These scales scores showed moderate to good internal consistence (omega values ranged from .54 to .86). Inconsistent parenting scores achieved the strongest associations with external measures of psychopathology, especially for externalizing and conduct problems, as well as for functional impairment, the poorest associations being for the positive parenting scores. Results support the validity of the Spanish APQ-Pr, which is potentially a useful measure for the study of parenting practices regarding preschool children and their relation to conduct problems.  相似文献   
29.
The assessment of varied psychiatric disorders, including obsessive–compulsive disorder (OCD), is shifting towards the use of evidence-based assessments (EBAs). This shift has fostered the development, validation and adaptation of several measures to rate obsessive–compulsive symptoms and other related problematic areas such as functional impairment or family attitudes among others. The aim of this paper is to present a systematic review of psychometric studies on pediatric OCD-specific measures to classify these according to assessment evidence-based criteria. Selection criteria that determined which studies were included in the review were: (1) analyzing an OCD measure and (2) including participants’ age being 18 years or younger. The literature search procedure was conducted in Medline, PsycINFO, PsycARTICLES, ERIC, Cochrane Library, and Scholar Google databases and enabled us to locate 42 studies which analyzed psychometric properties of 14 OCD measures studied in children and adolescents. Instruments were grouped into the following assessment areas: symptom presence and severity, functional impairment, family functioning and cognitive dimensions of OCD. Psychometric data regarding internal structure, internal consistency, reliability, validity and diagnostic precision were also reported. Further, measures were classified as well-established, approaching well-established and promising assessments in terms of reliability and validity. We concluded that the assessment of OCD in pediatric populations is a growing field that in a short-medium term could provide a wide variety of EBAs for the evaluation obsessive–compulsive symptoms and other OCD-related dimensions. The paper concludes by highlighting directions for future research.  相似文献   
30.
The survival processing paradigm has recently drawn attention to the functional aspects of memory functioning. The survival effect, characterized by better memory performance when information is processed in a survival context, as compared with a variety of controls, is now well established in healthy populations. The main goal of this study was to test this paradigm in a group of cognitively impaired older adults and elderly; their data were compared to the data obtained in a group of healthy older adults and elderly. Seventeen cognitively impaired and 17 healthy participants performed a typical survival task using a blocked within‐subject design procedure and free recall as the memory test. The healthy older adults and elderly performed better on this memory task as well as on other tests included in a neuropsychological evaluation protocol. Importantly, both groups benefited from survival processing. These results provide further support for the power of survival processing, extending this phenomenon to cognitively impaired aging participants. The data also suggest that the survival effect is not simply a form of deep processing. Potential applied considerations are presented.  相似文献   
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