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61.
We were concerned with the effects of item repetition, list length, and class of item on free recall in elderly as compared with young adults. In Experiment 1, samples of young and elderly adults recalled a list of 27 words and a list of 27 action events (minitasks performed by the subjects). Some items were presented once and some twice. Although the younger subjects showed better recall on both types of lists, the older sample benefited from item repetition as much as did the younger sample. This finding was replicated in Experiment 2. A second finding in Experiment 2 was a significant aging effect in the recall of long but not of short lists of both words and action events. The absence of an Age?×?Repetition Effect interaction was ascribed to the strength nature of the repetition manipulation. The age effects in the recall of the long lists were attributed to possible deficits in retrieval proficiency. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Four intervention models that aim to reduce problematic caregiver–infant relationships are reviewed within the context of attachment theory. These models include support, guidance, psychotherapy, and infant-led psychotherapy. All of the models are consistent with attachment theory in that they aim to enhance maternal sensitivity and responsiveness. Only infant-led psychotherapy focuses primarily on the mother–infant relationship and directly includes the infant in treatment instead of focusing and working primarily with the more verbal partner, the caregiver. Thus, of the 4 interventions, infant-led psychotherapy is most consistent with the current empirical and theoretical understanding of infants as active contributors to their relationships and development. However, there is little empirical research on this intervention; the bulk of studies evaluate support and guidance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
Add-drop filters are demonstrated using silica-on-silicon optical waveguide technology. This device consists of a full directional coupler subdivided by Mach-Zehnder sections. Tapering of the coupling coefficients is experimentally shown to dramatically reduce the filters' sidelobes. Only one photolithographic step is required using the silica planar waveguide technology, yielding accurate wavelength control of the filters. Excellent agreement between measurement and design was achieved 相似文献
64.
SD Walter SE Birnie LD Marrett SM Taylor D Reynolds J Davies JJ Drake M Hayes 《Canadian Metallurgical Quarterly》1994,84(3):367-376
OBJECTIVES: Our objectives were (1) to describe an analysis of the spatial pattern of cancer incidence in Ontario and (2) to discuss the quality of data in the Ontario Cancer Registry with respect to the accuracy of local cancer rates. METHODS: Cancer incidence rates were calculated for 22 cancer sites in 49 counties of Ontario during 1976 to 1986. Capture-recapture methods were used to estimate completeness of case registration, and completeness of residence information was also assessed. Spatial autocorrelation was used in measuring the geographic pattern of incidence rates. Comparisons were also made between sexes and with earlier data from 1966 to 1975. RESULTS: The quality of the geographic data in the registry appeared good, and corrections for incomplete or inaccurate registration had little impact. About one third of the sex-site combinations showed some evidence of spatial patterning in the cancer rate. Particularly strong regional variation was noted for cancers of the stomach, lung, uterus, and prostate. CONCLUSIONS: The analysis revealed a number of cancers with significant spatial patterning of risk. Further work is needed to relate the cancer data to other information on potential life-style and environmental factors. 相似文献
65.
High spatial order finite element method to solve Maxwell's equations in time domain 总被引:2,自引:0,他引:2
Pernet S. Ferrieres X. Cohen G. 《Antennas and Propagation, IEEE Transactions on》2005,53(9):2889-2899
This paper presents a finite element method with high spatial order for solving the Maxwell equations in the time domain. In the first part, we provide the mathematical background of the method. Then, we discuss the advantages of the new scheme compared to a classical finite-difference time-domain (FDTD) method. Several examples show the advantages of using the new method for different kinds of problems. Comparisons in terms of accuracy and CPU time between this method, the FDTD and the finite-volume time-domain methods are given as well. 相似文献
66.
Y. Cohen K. Landskron N. Ttreault S. Fournier‐Bidoz B. Hatton G.A. Ozin 《Advanced functional materials》2005,15(4):593-602
The synthesis and characterization of a novel silicon–silica nanocomposite material are reported. A self‐assembly method allows the encapsulation of silicon nanoclusters within the channels of a periodic mesoporous silica thin film. The result is the formation of a silicon–silica nanocomposite film with bright, room‐temperature photoluminescence in the visible range, and a nanosecond luminescence lifetime. The properties of the nanocomposite material have been studied by several analytical techniques, which collectively show the existence within the channels of non‐diamondoid‐structure‐type silicon nanoclusters with various hydrogenated silicon sites. It is estimated that the silicon nanoclusters in the silica mesoporous films occupy up to 39 % of the accessible pore volume. The nanocomposite film shows improved resistance to air oxidation compared to crystalline silicon. The high loading and chemical stability to oxidation under ambient conditions are important advantages in terms of the development of silicon‐based light‐emitting diodes from this class of materials. 相似文献
67.
Cohen Lawrence H.; Burt Charles E.; Bjorck Jeffrey P. 《Canadian Metallurgical Quarterly》1987,23(4):583
A longitudinal design was used to test the effects of life events experienced by young adolescents and their parents. The criteria were the adolescents' depression, anxiety, and self-esteem. The longitudinal analysis revealed a significant effect for the adolescents' controllable, but not uncontrollable, negative events. However, causal analyses revealed that this effect was the result of the significant relation between initial adjustment and the subsequent occurrence of controllable life stress (e.g., school suspension). The longitudinal analysis also revealed the stress-protective role of positive events, but only with respect to girls' self-esteem. There was no longitudinal support for the role of the parents' negative life events. These findings do not support the etiological importance of an accumulation of relatively discrete negative events experienced by early adolescents and their parents, but they do suggest the need (a) to conceptualize (controllable) life stress as a dependent variable in future research on developmental psychopathology; (b) to examine gender differences in early adolescent life stress; and (c) to develop more sophisticated measures of family life stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
69.
Two studies explored how domestic violence may be implicitly or explicitly sanctioned and reinforced in cultures where honor is a salient organizing theme. Three general predictions were supported: (a) female infidelity damages a man's reputation, particularly in honor cultures; (b) this reputation can be partially restored through the use of violence; and (c) women in honor cultures are expected to remain loyal in the face of jealousy-related violence. Study 1 involved participants from Brazil (an honor culture) and the United States responding to written vignettes involving infidelity and violence in response to infidelity. Study 2 involved southern Anglo, Latino, and northern Anglo participants witnessing a "live" incident of aggression against a woman (actually a confederate) and subsequently interacting with her. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
N Goupil-Feuillerat M Cocaign-Bousquet JJ Godon SD Ehrlich P Renault 《Canadian Metallurgical Quarterly》1997,179(20):6285-6293
The alpha-acetolactate decarboxylase gene aldB is clustered with the genes for the branched-chain amino acids (BCAA) in Lactococcus lactis subsp. lactis. It can be transcribed with BCAA genes under isoleucine regulation or independently of BCAA synthesis under the control of its own promoter. The product of aldB is responsible for leucine sensibility under valine starvation. In the presence of more than 10 microM leucine, the alpha-acetolactate produced by the biosynthetic acetohydroxy acid synthase IlvBN is transformed to acetoin by AldB and, consequently, is not available for valine synthesis. AldB is also involved in acetoin formation in the 2,3-butanediol pathway, initiated by the catabolic acetolactate synthase, AlsS. The differences in the genetic organization, the expression, and the kinetics parameters of these enzymes between L. lactis and Klebsiella terrigena, Bacillus subtilis, or Leuconostoc oenos suggest that this pathway plays a different role in the metabolism in these bacteria. Thus, the alpha-acetolactate decarboxylase from L. lactis plays a dual role in the cell: (i) as key regulator of valine and leucine biosynthesis, by controlling the acetolactate flux by a shift to catabolism; and (ii) as an enzyme catalyzing the second step of the 2,3-butanediol pathway. 相似文献