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41.
42.
The process by which metamemory and academic causal attributions relate to recall was examined with hierarchical multiple regression analyses. Several alternative conceptualizations of metamemory were used: general metamemory unrelated to the specific task; task-specific metamemory; memory monitoring; and both general and task-specific attributions. In order to examine the additive benefits of strategy and monitoring instructions, 81 4th graders were assigned to 1 of 4 instructional conditions: Strategy Only, Process Monitoring Only, Strategy Plus Process Monitoring, or Practice-Control group. Regression analyses indicated that the relationships between metamemory and recall depended on how metamemory was assessed and on the timing of the child's engagement with the recall task. Whereas general metamemory was significantly related to recall on the posttest and near-transfer tasks, task-specific metamemory became more relevant for transfer. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
Hypothesized that college women's locus of control orientations would be related to their role expectations, with women with an external locus of control having lower aspirations, more conservative sex-role ideologies, and less involvement in career planning than women with an internal locus of control. 116 female college juniors and seniors completed a career expectation scale, the Adult Nowicki-Strickland Internal-External Control Scale (ANSIE), and an index of sympathy for women's liberation ideology. Regression analyses using ANSIE scores as the predictor variable supported the hypotheses. Compared to Ss with internal orientations, Ss with external orientations expected to have less commitment to their careers, to work for a smaller portion of their lives, and to feel more discomfort due to violating sex-role stereotypes. In addition, Ss with a more external orientation reported less career planning activity, less positive feelings about their future careers, and more conservative views on women's liberation ideology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
44.
Indirect evidence has suggested that lipid peroxidation is associated with iron overload in vivo. As a measure of lipid peroxidation, pentane expired in the breath of rats loaded with an accumulated dose of either 100 mg or 186–200 mg of iron injected intraperitoneally as iron dextran was measured over a 7 to 8 week period, and the effect on pentane production of feeding antioxidant-supplemented diets was determined. By the seventh week of feeding the diets, rats fed 0.3% L-ascorbic acid produced 17% less (P=0.03) pentane than did rats fed the basal antioxidant-deficient diet, whereas rats fed 0.004% dl-α-tocopherol acetate produced 92% less (P<0.001). After being fed the basal diet for 7 weeks, iron-loaded rats produced 76±9 pmol pentane/100 g body wt/min. When synthetic antioxidants were added to the diet at a concentration of 0.25%, the order of effectiveness in decreasing pentane production after 1 week was: N,N′-diphenyl-p-phenylenediamine > ethoxyquin > butylated hydroxyanisole > butylated hydroxytoluene > propyl gallate ∼ no antioxidant. After removal of either ethoxyquin or N,N′-diphenyl-p-phenylenediamine from the diets for 1 week, pentane production increased to a high level. The total amount of lipid soluble fluorophores in individual spleens of rats fed N,N′-diphenyl-p-phenylenediamine, ethoxyquin, dl-α-tocopherol acetate, ascorbic acid and no antioxidant were correlated significantly with the corresponding total integrated amount of pentane produced by the individual rats over the 7 to 8 week period. This study has provided some of the most direct evidence to date that lipid peroxidation is associated with iron overload in vivo.  相似文献   
45.
The last decade has witnessed an extraordinary shift in housing policy in Canada. Responsibility for social housing has been devoluted from the federal government to theprovincial and territorial governments, who in turn shift administration and manangement to regional and municipal agencies. And while the proportion of needy families is increasing, the deficit-minded Federal government only maintains its financial commitments to existing projects with no new funds presently available. Market solutions are being promoted by both the public and private sectors through a wide range of activities. The result is no single housing policy, but a patchwork of provincial and local initiatives.  相似文献   
46.
A 28-day accumulation study demonstrated the use of mussel uptake, passive samplers, and biodynamic modeling to measure the reduction of dichlorodiphenyltrichloroethane (DDT) availability in the water column after the addition of activated carbon to contaminated sediment. Sediment collected from Lauritzen Channel, Richmond, California (16.5 mg total DDT/kg) was mixed with either virgin activated carbon or a reactivated carbon for one month, after which a 28-day laboratory exposure study was completed. Mussels (Mytilus edulis) suspended above activated carbon-treated sediment accumulated significantly less total DDT in soft tissue, 91% and 84% for virgin and reactivated carbon, respectively, as compared to untreated sediment. Mussel tissue concentrations correlated to concentrations in semipermeable membrane devices (SPMDs) and polyethylene devices (PEDs) suspended over the same sediments. A biodynamic model that incorporated DDT water concentrations, either analytically measured or estimated from PED uptake, described mussel accumulation over time. Thus, passive samplers in combination with biodynamic modeling may provide an important screening tool for assessment of filter-feeding uptake and ecological risk to water-dwelling organisms exposed to aqueous phase hydrophobic organic contaminants.  相似文献   
47.
We demonstrate two-dimensional multiplexed real-time, label-free antibody-antigen binding assays by optically detecting nanoscale motions of two-dimensional arrays of microcantilever beams. Prostate specific antigen (PSA) was assayed using antibodies covalently bound to one surface of the cantilevers by two different surface chemistries, while the nonreaction surfaces were passivated by poly(ethylene glycol)-silane. PSA as low as 1 ng/mL was detected while 2 mg/microl of bovine serum albumin induced only negligible deflection on the cantilevers.  相似文献   
48.
The purpose of our analysis was to determine if older adults show sleep inertia effects on performance at scheduled wake time, and whether these effects depend on circadian phase or sleep stage at awakening. Using the Digit Symbol Substitution Test, effects of sleep inertia on performance were assessed over the first 30 min after wake time on baseline days and when sleep was scheduled at different circadian phases. Mixed model analyses revealed that performance improved as time awake increased; that beginning levels of performance were poorest when wake time was scheduled to occur during the biological night; and that effects of sleep inertia on performance during the biological night were greater when awaking from non-REM (NREM) sleep than from REM sleep. Based on our current understanding of sleep inertia effects in young subjects, and previous reports that older subjects awaken at an earlier circadian phase and are more likely to have their final awakening from NREM sleep than younger adults, our findings suggest older adults may be more vulnerable to sleep inertia effects than young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
The hydrothermal deep-sea vent fauna is naturally exposed to a highly specific environment enriched in potentially toxic species such as sulfides, metals and natural radionuclides due to the convective seawater circulation inside the oceanic crust and its interaction with basaltic or ultramafic host rocks. However, data on radionuclides in biota from such environment are very limited. An investigation was carried out on tissue partitioning of 210Po and 210Pb, two natural radionuclides within the 238U decay chain, in Bathymodiolus azoricus specimens from the Mid-Atlantic Ridge (Menez Gwen field). These two elements showed different distributions with high 210Pb levels in gills and high 210Po levels in both gills and especially in the remaining parts of the body tissue (including the digestive gland). Various factors that may explain such partitioning are discussed. However, 210Po levels encountered in B. azoricus were not exceptionally high, leading to weighted internal dose rate in the range 3 to 4 μGy h− 1. These levels are slightly higher than levels characterizing coastal mussels (~ 1 μGy h− 1).  相似文献   
50.
Predictions made by models of water-level acquisition were tested to understand better the sensory factors, cognitive factors, or both, that differentiate people who fail the test (low scorers) from people who pass (high scorers). Experiments 1 and 2 showed that in a horizontal-edge detection task, low scorers were less likely than high scorers to "see" liquid edges in tilted containers as horizontal. Experiment 3 showed that water-level type displays belong to a class of tilt illusions that arise from early visual processes for both low and high scorers, but only high scorers spontaneously use cognitive schemes to minimize illusory tilt. In Experiment 4, high scorers, but not low scorers, overrode the orientation illusion in a production task. The findings suggest bottom-up processes cause embedded lines to be misperceived for both groups, but high scorers are more likely to use cognitive schemes spontaneously to overcome the orientation illusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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