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51.
Blotcky Alan D.; Cohen Debra G.; Conatser Cheryl; Klopovich Patricia 《Canadian Metallurgical Quarterly》1985,53(5):729
Examined psychosocial variables by comparing 10 13–17 yr old adolescents (and their mothers) who had refused cancer treatment with a group of 10 consenting adolescents who were matched on age and demographic and illness variables. Adolescents completed the State-Trait Anxiety Inventory for Children and measures of family characteristics, locus of control, religion, hopelessness, impact of event, and satisfaction with physician. Mothers completed the State-Trait Anxiety Inventory and measures of coping and religion. Adolescent refusers scored lower on state anxiety and subjective distress but scored higher on trait anxiety, religiosity, and external locus of control. Their mothers also scored higher than did the consenting-group mothers on religiosity and trait anxiety. It is suggested that refusers are prone to anxiety and cope with their present distress by maintaining the belief that their lives are determined by fate or religious convictions. An intervention approach that fosters mastery over the cancer experience is advocated. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A systematic study of wall effects on the shear viscosity of short glass fiber-filled polypropylene and polystyrene is presented. The dependence of these effects on capillary radius, shear rate, temperature, and polymer matrix is examined. The “true” viscosity curves of these materials (free from wall effects) can be obtained by an extrapolation procedure. Breakage of glass fibers in the high shear-rate processes of extrusion and injection molding lead to an appreciable reduction of the viscosity of these materials and is probably the more important effect to take into account in these processes. 相似文献
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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
57.
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
58.
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
59.
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
60.
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