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171.
In the present paper the role of the state of the psychological contract to predict psychological health results is studied in a sample of 385 employees of different Spanish companies. Results indicate that the state of the psychological contract significantly predicts life satisfaction, work-family conflict and well-being beyond the prediction produced by the content of the psychological contract. In addition, trust and fairness, two dimensions of the state of psychological contract, all together contribute to explain these psychological health variables adding value to the role as predictor of fulfillment of the psychological contract. The results support the approach argued by Guest and colleagues.  相似文献   
172.
We describe the design and evaluation of an electronic system for the automatic recording of motor activity in rats. The device continually locates the position of a rat inside a transparent acrylic cube (50 cm/side) with infrared sensors arranged on its walls so as to correspond to the x-, y-, and z-axes. The system is governed by two microcontrollers. The raw data are saved in a text file within a secure digital memory card, and offline analyses are performed with a library of programs that automatically compute several parameters based on the sequence of coordinates and the time of occurrence of each movement. Four analyses can be made at specified time intervals: traveled distance (cm), movement speed (cm/s), time spent in vertical exploration (s), and thigmotaxis (%). In addition, three analyses are made for the total duration of the experiment: time spent at each xy coordinate pair (min), time spent on vertical exploration at each xy coordinate pair (s), and frequency distribution of vertical exploration episodes of distinct durations. User profiles of frequently analyzed parameters may be created and saved for future experimental analyses, thus obtaining a full set of analyses for a group of rats in a short time. The performance of the developed system was assessed by recording the spontaneous motor activity of six rats, while their behaviors were simultaneously videotaped for manual analysis by two trained observers. A high and significant correlation was found between the values measured by the electronic system and by the observers.  相似文献   
173.
In Higher Education, performance and Teaching-Learning (T-L) contexts are highly current concerns. Based on the DEDEPRO model, interdependence can be established between instructional contexts and levels of performance as they relate to the T-L process. Partitipants were 2020 pupils from two Spanish universities. Measurements of both variables were used in a quasi-experimental and correlational design. The univariate and causal analyses showed the effect of context on the T-L process and on performance; thus, the interdependent relationships between the latter and perception of the T-L process. Partial interaction effects also appeared, as well as a causal model of academic performance. Results are discussed and implications for the ECTS (European Credit Transfer System) are analyzed.  相似文献   
174.
The most acknowledged strategies for the treatment of disruptive behaviours are those that are based on direct contingency management. Other procedures allow the therapist, or educational agent, not to be present in the context in which the behavioural change has to take place: the say-do correspondence training procedures, which have proven effective across behaviours and populations. Nevertheless, there is surprisingly little evidence of the effectiveness of such procedures with populations presenting developmental disabilities. This study describes the implementation of say-do correspondence training to modify 5 disruptive behaviours present in 5 adult subjects diagnosed with Down's syndrome, showing very positive results. The advantages of using say-do correspondence training procedures in developmental disabilities are discussed.  相似文献   
175.
We discuss Kunen’s algorithmic implementation of a proof for the Paris–Harrington theorem, and the author’s and da Costa’s proposed “exotic” formulation for the P = NP hypothesis. Out of those two examples we ponder the relation between mathematics within an axiomatic framework, and intuitive or informal mathematics. The author is Visiting Researcher at IEA/USP, Professor of Communications, Emeritus, at the Federal University in Rio de Janeiro, and a full member of the Brazilian Academy of Philosophy.  相似文献   
176.
Several findings relate the hippocampal formation to the behavioural consequences of stress. It contains a high concentration of corticoid receptors and undergoes plastic modifications, including decreased neurogenesis and cellular remodelling, following stress exposure. Various major neurotransmitter systems in the hippocampus are involved in these effects. Serotonin (5-HT) seems to exert a protective role in the hippocampus and attenuates the behavioural consequences of stress by activating 5-HT1A receptors in this structure. These effects may mediate the therapeutic actions of several antidepressants. The role of noradrenaline is less clear and possibly depends on the specific hippocampal region (dorsal vs. ventral). The deleterious modifications induced in the hippocampus by stress might involve a decrease in neurotrophic factors such as brain derived neurotrophic factor (BDNF) following glutamate N-methyl-D-aspartate (NMDA) receptor activation. In addition to glutamate, nitric oxide (NO) could also be related to these effects. Systemic and intra-hippocampal administration of nitric oxide synthase (NOS) inhibitors attenuates stress-induced behavioural consequences. The challenge for the future will be to integrate results related to these different neurotransmitter systems in a unifying theory about the role of the hippocampus in mood regulation, depressive disorder and antidepressant effects.  相似文献   
177.
Three experiments with rats used conditioned suppression of barpress to test predictions of the extended comparator hypothesis, which assumes that the effectiveness of (first-order) comparator stimuli in modulating responding to a target conditioned stimulus (CS) is itself modulated by other (second-order) comparator stimuli. Experiment 1 demonstrated that both pretraining exposure to the target CS alone (i.e., CS-preexposure effect, also known as latent inhibition) and pretraining exposure to a compound of the target CS and nontarget CS (i.e., compound-CS-preexposure effect) counteract overshadowing, and that posttraining deflation (i.e., extinction) of the overshadowing stimulus attenuates responding to the target CS when overshadowing is preceded by a CS-preexposure treatment (i.e., yields a CS-preexposure effect), but not when overshadowing is preceded by a compound-CS-preexposure treatment. Experiment 2 examined the consequences of posttraining associative inflation of the overshadowing stimulus or the preexposure companion stimulus following conjoint compound-CS-preexposure and overshadowing treatment. Experiment 3 examined the consequences of posttraining inflation of the overshadowing stimulus or the context following conjoint CS-alone preexposure and overshadowing treatment. The results support the expression-focused comparator view in contrast to recent acquisition-focused models of retrospective revaluation.  相似文献   
178.
In clinical practice, older people with cognitive impairment may have difficulties to understand the instructions of the Timed Up-and-Go (TUGT) test and present a bad performance. The purpose of this study was to identify differences in the TUGT performance, in an adapted version, between older adults with preserved cognition (PC), mild cognitive impairment (MCI) and Alzheimer's disease (AD), and to identify the association between the adapted TUGT performance and cognition among groups. A cross-sectional study was conducted with 118 community-dwelling older adults divided in three groups: PC (n?=?40), MCI (n?=?40) and AD (n?=?38). The evaluation was composed by the adapted TUGT and cognitive assessment (Addenbrooke's Cognitive Examination and Frontal Assessment Battery). Only the cadence of TUGT presented significant difference between groups, specifically between AD versus MCI and PC groups. The main correlations were found between time of TUGT with fluency domain and global cognitive function, especially in the AD Group. The findings contribute to the understanding of how cognition interferes on functional mobility in older people with MCI and AD. The adapted TUGT is easy to perform in clinical practice and can be useful when assessing mobility in people with cognitive impairment.  相似文献   
179.
A substantial body of research has established that emotion understanding develops throughout early childhood and has identified three hierarchical developmental phases: external, mental, and reflexive. The authors analyzed nonverbal intelligence and its effect on children's improvement of emotion understanding and hypothesized that cognitive level is a consistent predictor of emotion comprehension. In all, 366 children (182 girls, 184 boys) between the ages of 3 and 10 years were tested using the Test of Emotion Comprehension and the Coloured Progressive Matrices. The data obtained by using the path analysis model revealed that nonverbal intelligence was statistically associated with the ability to recognize emotions in the 3 developmental phases. The use of this model showed the significant effect that cognitive aspect plays on the reflexive phase. The authors aim to contribute to the debate about the influence of cognitive factors on emotion understanding.  相似文献   
180.
Interpretations of Einstein’s equation differ primarily concerning whether E = mc2 entails that mass and energy are the same property of physical systems, and hence whether there is any sense in which mass is ever ‘converted’ into energy (or vice versa). In this paper, I examine six interpretations of Einstein’s equation and argue that all but one fail to satisfy a minimal set of conditions that all interpretations of physical theories ought to satisfy. I argue that we should prefer the interpretation of Einstein’s equation that holds that mass and energy are distinct properties of physical systems. This interpretation also carries along the view that while most cases of ‘conversion’ are not genuine examples of mass being ‘converted’ into energy (or vice versa), it is possible that the there are such ‘conversions’ in the sense that a certain amount of energy ‘appears’ and an equivalent of mass ‘disappears’. Finally, I suggest that the interpretation I defend is the only one that does not blur the distinction between what Einstein called ‘principle’ and ‘constructive’ theories. This is philosophically significant because it emphasizes that explanations of Einstein’s equation and the ‘conversion’ of mass and energy must be top‐down explanations.  相似文献   
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