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排序方式: 共有347条查询结果,搜索用时 15 毫秒
41.
Unitary events in multiple single-neuron spiking activity: I. Detection and significance. 总被引:1,自引:0,他引:1
It has been proposed that cortical neurons organize dynamically into functional groups (cell assemblies) by the temporal structure of their joint spiking activity. Here, we describe a novel method to detect conspicuous patterns of coincident joint spike activity among simultaneously recorded single neurons. The statistical significance of these unitary events of coincident joint spike activity is evaluated by the joint-surprise. The method is tested and calibrated on the basis of simulated, stationary spike trains of independently firing neurons, into which coincident joint spike events were inserted under controlled conditions. The sensitivity and specificity of the method are investigated for their dependence on physiological parameters (firing rate, coincidence precision, coincidence pattern complexity) and temporal resolution of the analysis. In the companion article in this issue, we describe an extension of the method, designed to deal with nonstationary firing rates. 相似文献
42.
Huver Rose M. E.; Engels Rutger C. M. E.; Vermulst Ad A.; de Vries Hein 《Canadian Metallurgical Quarterly》2007,26(6):762
Objective: Parenting is generally regarded a determinant of adolescent behavior, whereas the reverse is seldom considered. Reported effects of anti-smoking parenting practices on adolescent smoking are inconsistent. Cross-sectional results may have been misinterpreted and child effects have been overlooked. The main goal of this study was to explain previous inconsistent effects of anti-smoking parenting practices, by examining bi-directional relations between parenting and adolescent smoking. Design and Main Outcome Measures: Bi-directional relations were studied using a cross-lagged model where anti-smoking house rules, communication about smoking, and adolescent smoking were assessed at three subsequent years. Results: The most prominent finding was that adolescent smoking behavior was a stronger predictor of parenting than vice versa. Anti-smoking house rules decreased as a result of adolescent smoking behavior, while communication increased. The reduction in house rules was more pronounced if parents smoked, while the increase in communication was greater for non-smoking parents. Results were independent of adolescent sex. Conclusion: Further research is needed to establish which aspects of parenting can be effective in deterring adolescent smoking. This study emphasizes the need for caution in interpreting cross-sectional research findings relating parenting to adolescent smoking. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Memory Fault Modeling Trends: A Case Study 总被引:1,自引:1,他引:0
Said Hamdioui Rob Wadsworth John Delos Reyes Ad J. van de Goor 《Journal of Electronic Testing》2004,20(3):245-255
In recent years, embedded memories are the fastest growing segment of system on chip. They therefore have a major impact on the overall Defect per Million (DPM). Further, the shrinking technologies and processes introduce new defects that cause previously unknown faults; such faults have to be understood and modeled in order to design appropriate test techniques that can reduce the DPM level. This paper discusses a new memory fault class, namely dynamic faults, based on industrial test results; it defines the concept of dynamic faults based on the fault primitive concept. It further shows the importance of dynamic faults for the new memory technologies and introduces a systematic way for modeling them. It concludes that current and future SRAM products need to consider testability for dynamic faults or leave substantial DPM on the table, and sets a direction for further research. 相似文献
44.
van den Eijnden Regina J. J. M.; Meerkerk Gert-Jan; Vermulst Ad A.; Spijkerman Renske; Engels Rutger C. M. E. 《Canadian Metallurgical Quarterly》2008,44(3):655
The present study investigated the relationships between adolescents' online communication and compulsive Internet use, depression, and loneliness. The study had a 2-wave longitudinal design with an interval of 6 months. The sample consisted of 663 students, 318 male and 345 female, ages 12 to 15 years. Questionnaires were administered in a classroom setting. The results showed that instant messenger use and chatting in chat rooms were positively related to compulsive Internet use 6 months later. Moreover, in agreement with the well-known HomeNet study (R. Kraut et al., 1998), instant messenger use was positively associated with depression 6 months later. Finally, loneliness was negatively related to instant messenger use 6 months later. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Ohne Zusammenfassung 相似文献
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The oxidation of formaldehyde in sodium hydroxide solution has been studied on platinum and gold single crystal electrodes with the (111), (110) and (100) orientations. There is apparently no structural sensitivity of this reaction, since minor differences have been found between the three low index faces. This is valid for both platinum and gold electrodes. The hydrogen adsorption on platinum and the AuOH formation on gold electrodes exhibit structural sensitivity in the same solution. Similar activity of platinum and gold electrodes is noteworthy. A weak adsorption of gem-diol, formed in the interaction of formaldehyde with H2O or OH? appears as the origin of the structural insensitivity of this reaction. 相似文献
48.
Rhode Heyns G. Weiss Schwaibold Steingroever Hans Müller Kanitz H. J. Steinbeck K. Felix K. Höll P. de Fremery Edward Hofmann Konrad Lang O. Windhausen Trendtel W. Leithe W. Schulze Ilse Gaede v. Noël Jesser H. Elsner Pieper W. Schreiber Rudolf Abderhalden Renate Teske Hanson I. Stahn Krzywanek Fr. Bartschat Lars Erlandsen Ad. Hanak W. Bartels Kluge E. -E. Bauke Karl Bernhard G. Steinhoff W. Hämmerle C. I. Kruisheer Brüning Reichard K. J. Demeter M. Gordienko Flössner Jahr Diemair H. Mohler 《European Food Research and Technology》1939,78(1):48-112
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