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991.
992.
It is argued that children need to learn about civic issues intheir education because certain virtues are required for a decently organisedsociety. It is also argued that the school has wide obligations to educate theyoung in civics because it is in their best interests. This is not seen asan encroachment on the privacy of the individual. It is explained that theschool has an obligation to impart knowledge to the young. 相似文献
993.
994.
In this paper we study in details a system of two weakly coupled harmonic oscillators from the point of view of Bohm’s interpretation
of quantum mechanics. This system may be viewed as a simple model for the interaction between a photon and a photodetector.
We obtain exact solutions for the general case. We then compute approximate solutions for the case where one oscillator is
initially in its first excited state (a single photon) reaching the other oscillator in its ground state (the photodetector).
The approximate solutions represent the state of both oscillators after the interaction, which is not an eigenstate of the
individual hamiltonians for each oscillator, and therefore the energies for each oscillator do not exist in the Copenhagen
interpretation of Quantum Mechanics. We use the approximate solutions that we obtained to compute Bohmian trajectories and
to study the energy transfer between the oscillators. We conclude that, even using the Bohmian view, the energy of each individual
oscillator is not well defined, as the nonlocal quantum potential is not negligible even after the coupling is turned off. 相似文献
995.
When observers are asked to report a feature of a single target displayed in rapid serial visual presentation, they frequently make errors. Most frequently, a feature from the to-be-reported dimension pertaining to a stimulus presented near the target is reported. These migrations are so-called illusory conjunctions in the time domain. From parallel models, it is proposed that during the presentation of the series, the response features of the stimuli are extracted. If a high rate of presentation does not enable proper binding processes, the system could base its response on sophisticated guessing on the basis of the relative levels of activation of the available response features. However, the multiple extractions assumption has not received direct empirical support. We report two experiments in which the observers had to report their first and second response candidates. This double response paradigm makes it possible to test the assumption that more than one response feature is available for making a response. Furthermore, the application of the constant ratio rule (following Botella, Barriopedro, & Suero's, 2001, model) to the first responses allows predictions for the ratios between choices of the items for the second responses. The correlations between the observed and the predicted response proportions were .887 and .956 in the two experiments. This high predictive capacity indicates, first, that the observers have more than one response available, among which to choose, and second, that the choice among responses is determined largely in the same way for both, first and second responses. Nevertheless, the small errors in prediction are further reduced if a proportion of pure guesses is assumed in the second responses. These are probably due to memory losses, misidentifications of the features, and other factors impairing performance in second responses in comparison with first responses. 相似文献
996.
To assemble a calibrated set of compassion-eliciting visual stimuli, 60 clinically healthy Mexican volunteers (36 women, 24 men; M age = 27.5 yr., SD = 2.4) assessed 84 pictures selected from the International Affective Picture System catalogue using the dimensions of Valence, Arousal, and Dominance included in the Self-assessment Manikin scale and an additional dimension of Compassion. Pictures showing suffering in social contexts and expressions of sadness elicited similar responses of compassion. The highest compassion response was reported for pictures showing illness and pain. Men and women differed in the intensity but not the quality of the compassionate responses. Compassion included attributes of negative emotions such as displeasure. The quality of the emotional response was not different from that previously reported for samples in the U.S.A., Spain, and Brazil. A set of 28 pictures was selected as high-compassion-evoking images and 28 as null-compassion controls suitable for studies designed to ascertain the neural substrates of this moral emotion. 相似文献
997.
Jesús L. Megías Estrella Ryan Joaquín M. M. Vaquero Bettina Frese 《Applied cognitive psychology》2007,21(1):117-130
According to most post‐traumatic stress disorder (PTSD) theories, memory mechanisms are involved in its development and maintenance. However, the specific memory characteristics responsible for this disorder are still not well known. In the present study, 210 participants having reported at least one traumatic experience were assigned to a PTSD or to a non‐PTSD symptom profile group. Both groups rated their memories for their most traumatic and intense positive life events. We observed that the traumatic memories of PTSD profile participants were more clear, detailed and judged as significant compared with those of the non‐PTSD profile group. However, participants in the first group acknowledged having more difficulties putting their traumatic memories into words and controlling these remembrances. These differences were absent in their positive memories. Additionally, clear relationships emerged between memory ratings and PTSD symptoms measures. Results are discussed according to fragmentation and superiority views of traumatic memories in PTSD. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
998.
Humans show pronounced individual differences in circadian orientation. Transcultural comparisons are interesting since biological (or environmental) factors together with cultural ones may contribute to differences in morningness–eveningness. We compared Spanish and German undergraduates using the Composite Scale of Morningness (CSM) to assess circadian preferences. Confirmatory and multiple groups confirmatory factor analysis were used to assess factor structure and structural invariance across countries. The results showed that a three‐factor model of morningness best characterises the CSM structure of both samples. Partial factorial invariance (factor loadings) across countries was demonstrated for the factors ‘morningness’ and ‘morning alertness’. Scores of both factors were higher in German students. Potential cultural and biological explanations for the differences are discussed. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
999.
Differential effects of muscarinic receptor blockade in prelimbic cortex on acquisition and memory formation of an odor-reward task 下载免费PDF全文
Carballo-Márquez A Vale-Martínez A Guillazo-Blanch G Torras-Garcia M Boix-Trelis N Martí-Nicolovius M 《Learning & memory (Cold Spring Harbor, N.Y.)》2007,14(9):616-624
The present experiments determined the consequences of blocking muscarinic cholinergic receptors of the prelimbic (PL) cortex in the acquisition and retention of an odor-reward associative task. Rats underwent a training test (five trials) and a 24-h retention test (two retention trials and two relearning trials). In the first experiment, rats were bilaterally infused with scopolamine (20 or 5 microg/site) prior to training. Although scopolamine rats showed acquisition equivalent to PBS-injected controls, they exhibited weakened performance in the 24-h retention test measured by number of errors. In the second experiment, rats were injected with scopolamine (20 microg/site) immediately or 1 h after training and tested 24 h later. Scopolamine rats injected immediately showed severe amnesia detected in two performance measures (errors and latencies), demonstrating deficits in retention and relearning, whereas those injected 1 h later showed good 24-h test performance, similar to controls. These results suggest that muscarinic transmission in the PL cortex is essential for early memory formation, but not for acquisition, of a rapidly learned odor discrimination task. Findings corroborate the role of acetylcholine in consolidation processes and the participation of muscarinic receptors in olfactory associative tasks. 相似文献
1000.