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931.
Amanda Brown Cross Denise C. Gottfredson Denise M. Wilson Melissa Rorie Nadine Connell 《American journal of community psychology》2010,45(3-4):370-380
Data collected during an evaluation of a multi-site trial of an enhanced after-school program were used to relate quality of program implementation to student experiences after school. The enhanced after-school program incorporated a drug use and violence prevention component that was shown to be effective in previous research. Building on Durlak and Dupre’s (Am J Community Psychol 41:327–350, 2008) dimensions of implementation, we assessed the level of dosage, quality of management and climate, participant responsiveness, and staffing quality achieved at the five program sites. We evaluated how these characteristics co-varied with self-reported positive experiences after-school. The study illustrates how multiple dimensions of program implementation can be measured, and shows that some but not all dimensions of implementation are related to the quality of student after-school experiences. Measures of quality of management and climate, participant responsiveness, and staffing stability were most clearly associated with youth experiences. The importance of measuring multiple dimensions of program implementation in intervention research is discussed. 相似文献
932.
Recent temporal distinctiveness models of memory predict that temporally isolated items will be recalled better than temporally
crowded items. The effect has been found in some tasks (free recall, memory for serial order when report order is unconstrained,
running memory span) but not in others (forward serial recall). Such results suggest that the attentional weighting given
to a temporal dimension in memory may vary with task demands. Here, we find robust temporal isolation effects in recognition
memory (Experiment 1) and a smaller isolation effect in forward serial recall when an open pool of items is used (Experiment
2). Analysis of 26 temporal isolation effects suggests that the phenomenon occurs in a range of tasks but is larger when it
is useful to attend to a temporal dimension in memory. The overall pattern of results is taken to favor memory models that
rely on multiple weighted dimensions in memory, one of which is temporal. 相似文献
933.
Abstract Experimental results for two-dimensional grain growth are compared with the results obtained from computer-generated random threefold vertex networks with a fixed one-particle distribution function. A considerable discrepancy in the two-particle distributions implies some kind of short-range order. New results in the computer simulation of normal grain growth are reported, demonstrating a similar kind of ordering. A simple relation is suggested for the quantity m n, introduced by Aboav and the second moment of the one-particle distribution μ2 相似文献
934.
This paper is concerned with the implications of vacancy-pair mechanisms on chemical diffusion in intermetallic compounds with the B2 structure. The discussion specifically includes the so-called triple-defect mechanism. It is shown that the vacancy-pair mechanism cannot contribute to chemical diffusion in the intermetallic compound at the stoichiometric composition AB. Focusing on the triple-defect mechanism we extend it to non-stoichiometric compositions by including isolated antistructural atoms. By means of Monte Carlo simulation we show that the efficiency of the triple-defect mechanism in providing for chemical diffusion increases linearly with increasing antistructural atom composition but the efficiency remains relatively low unless the composition is highly non-stoichiometric. 相似文献
935.
An enhancement of the UV-visible optical absorption spectra of Ag nanoparticles (NPs) deposited on indium tin oxide (ITO) surfaces of different resistance by a seed-mediated growth technique is presented. A bicolour coherent beam, obtained from a pulsed Nd:YAG laser providing a 1060-nm fundamental wavelength and a double-frequency one at 530?nm, was used. A significant change in the optical density is observed for Ag NPs on low-resistance ITO surfaces (≈4?Ω/square), while almost nothing occurs with high-resistance (≈50?Ω/square surfaces). The spectral position of the maximal absorption at 440?nm is almost preserved in both cases. This result is explained in terms of a local photoinduced static field and surface-plasmon polaritons interacting with photoexcited phonons. A grating effect, arising from the coherent bicolour light forming a superstructure as for quantum crystals, could be another contribution. 相似文献
936.
937.
Gordon D. A. Brown Marie Poirier Claudette Fortin Ian Neath 《Memory (Hove, England)》2013,21(3-4):225-235
Abstract The role of current personal experience in understanding of word meaning was investigated in a patient, WM, who suffers from semantic dementia. The study was prompted by the observation that WM, despite being severely impaired on formal tests of word comprehension and naming, retained a range of vocabulary pertaining to her daily life. If autobiographical experience has a general facilitatory effect, then this should affect which concepts are retained and which lost, but not influence the quality of that conceptual knowledge. Conversely, if personal autobiography has a direct role in investing concepts with meaning, then WM's understanding of nominal terms that she uses spontaneously in conversation ought not to be normal, but should be constrained by the autobiographical context in which she uses those terms. WM could define nouns and noun phrases drawn from her conversational vocabulary, but her definitions had a markedly autobiographical quality. Moreover, WM was extremely impaired in her ability to define new noun phrases, constructed by combining words from her conversational vocabulary (e.g. “dog licence”, constructed from “driving licence” and “dog” “oil field” constructed from “oil” and “field”). It was concluded that WM does not have normal conceptual understanding of nouns and noun phrases that she uses appropriately in conversation. Her understanding is narrow and autobiographically constrained. The findings, which suggest an interactive relationship between autobiographical and semantic memory, have implications for understanding of the progressive breakdown of semantic knowledge. 相似文献
938.
Alan S. Brown 《Memory (Hove, England)》2013,21(2):159-174
Using a picture naming task, we compared the magnitude of repetition priming after one prior study episode (single test priming) versus multiple prior study presentations (multiple test priming). Pictures were repeated either one, two, or three times, and the interval between tests was either several minutes (blocked test) or one week (spaced test). Priming increased with additional prior presentations (beyond one) in the multiple test format. In addition, single test priming decreased within one hour after initial exposure, with little change from one hour to two weeks. Priming was unaffected by a simultaneous recognition task, suggesting that picture naming is an implicit task relatively immune from explicit memory contamination. 相似文献
939.
E.V. Subbotsky 《Memory (Hove, England)》2013,21(2):199-224
In three experiments, adult subjects' explanations of the observed nonpermanence of a physical object and their recollections of the order of the events during the experiment were obtained and analysed. The data showed that in order to conserve their strong beliefs in object permanence subjects systematically distorted the real temporal succession of events preceding the phenomenon. The frequency of the distortions depended on the salience of the nonpermanence phenomenon (“disappearance” versus “appearance” of the physical object) and on the time interval between the events whose temporal order was reversed, but not on subjects' nationality (English versus German), gender, type of reproduction (immediate versus delayed), role in the experiment (subject versus observer), and degree of prompting in questioning. 相似文献
940.
Abstract Two experiments studied memory for the appearance of a Danish 20 kroner coin. The coin bears the portrait of Queen Margrethe II in profile, facing to the right. Previous studies have examined memory for British coins, which similarly bear a right-facing portrait of Queen Elizabeth II. They have revealed the occurrence of a mnemonic illusion, in that British people tend to believe the portrait faces left. This finding has been attributed to the occurrence of a joint coin-stamp schema. British stamps bear a left-facing profile of the Queen, and it is possible that information from the stamp predominates in the formation of the schema. In the case of Denmark, however, stamps bear a full-face portrait of the Queen. Nevertheless, the present experiments showed that the Coin Head Illusion is also found in Denmark. That is, the number of participants recalling the Queen's head as facing to the right was significantly below even the chance level of 50%. Further, this result occurred both for residents of Denmark and for visitors to Denmark. These findings suggest that the bias underlying the Coin Head Illusion may be a more general one than that envisaged by the joint coin-stamp schema hypothesis. 相似文献