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61.
One dimension of reading literacy involves the tracking of agents associated with the text. In a literary short story, there is a society of character agents and pragmatic agents. This study investigated the relative salience of different classes of agents in memory. Two experiments measured source memory as an index of agent salience in long-term memory. Patterns of source memory scores supported an invisible third-person narrator hypothesis and an agent amalgamation hypothesis, but not a structural prominence hypothesis: First-person narrator > nonnarrator character > third-person narrator > 0. Statement detection parameters did not significantly differ among the 3 classes of agents, so differences in source memory could not be explained by differences in the content of the speech acts. Source memory scores also could not be explained by surface features of the text, differences among readers, and sophisticated guessing on the basis of a story abstract. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Data from the Victoria Longitudinal Study were used to examine the hypothesis that maintaining intellectual engagement through participation in everyday activities buffers individuals against cognitive decline in later life. The sample consisted of 250 middle-aged and older adults tested 3 times over 6 years. Structural equation modeling techniques were used to examine the relationships among changes in lifestyle variables and an array of cognitive variables. There was a relationship between changes in intellectually related activities and changes in cognitive functioning. These results are consistent with the hypothesis that intellectually engaging activities serve to buffer individuals against decline. However, an alternative model suggested the findings were also consistent with the hypothesis that high-ability individuals lead intellectually active lives until cognitive decline in old age limits their activities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
63.
R. Elliott and M. M. Wexler (see record 1994-27938-001) have introduced the Session Impacts Scale (SIS), and W. B. Stiles et al (see record 1994-27969-001) have undertaken a new factor analysis of the Session Evaluation Questionnaire (SEQ) with a British sample of clients. These 2 measures of session-level psychotherapy effects have great potential as research tools. In this comment on the 2 articles, issues of retest reliability, the connection of session-level measures to research strategies based on other units of analyses, and suggested uses of the SIS and the SEQ are discussed. The importance of context-sensitive session impact research and of a comprehensive theory relating session impacts to therapy outcome is also stressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
64.
The chicken lysozyme silencer F2 (F2) thyroid hormone response element (TRE) contains an unusual everted palindromic arrangement, has a high affinity for thyroid hormone receptor (TR) homodimers, and is especially sensitive to dominant negative inhibition by, the T3 resistance (RTH) mutant TR beta P453H. We used various TREs and TR mutations to determine the mechanisms for this sensitivity. Changing the F2 orientation from an everted palindrome to a direct repeat with a 4-bp gap (DR+4) (F2-DR) decreased the sensitivity to inhibition at high T3 concentrations, while a loss of this sensitivity occurred with a palindromic arrangement of these same half-sites. F2 contains the dinucleotide TG 5' to each consensus half-site conforming to the optimal TR-binding octamer, YRRGGTCA. A T to A change in position 1 of both F2 half-sites markedly reduced T3-induction, yet only slightly reduced TR homodimer or TR-retinoid X receptor (RXR) heterodimer binding. The TR beta ninth heptad mutation, L428R, prevents TR heterodimerization with RXR and eliminates the inhibitory effect of the P453H mutant TR on the F2-DR, but not the F2 element. Structural features of a TRE that favor strong TR binding of both TR homodimers and TR-RXR heterodimers containing the mutant TR, such as the everted palindromic conformation or the optimal TR-binding consensus octamer, enhance the sensitivity of a TRE to inhibition by the mutant TR. Thus, both half-site orientation and sequence contribute to the sensitivity of a given TRE to dominant negative inhibition by a mutant TR.  相似文献   
65.
Hexavalent chromium (Cr(VI)) contamination of soil and groundwater is a major environmental concern for some industrial sites and most of the U.S. Department of Energy sites. Cr(VI) is toxic and fairly mobile in groundwater. Bioreduction of Cr(VI) to less toxic and less mobile Cr(III) is considered to be a feasible option. Among the Cr(VI) reducing bacteria, Shewanella oneidensis MR-1 (MR-1) has been shown to be effective in metal reduction under anaerobic conditions. Data on bioreduction of Cr(VI) by MR-1 in a flow-through soil column that better approximates the subsurface condition are not available. The objective of this research project was to study the bioreduction of Cr(VI) by MR-1 in a continuous-flow quartz sand column system. MR-1 was found to be very effective in reducing Cr(VI) to Cr(III) for concentrations ranging from 0.055 mM (2.85?mg/L) to 0.006 mM (0.31?mg/L). The amount of Cr(VI) reduced prior to its breakthrough was found to be inversely proportional to its concentration in the feed due to increased inhibition of microbial activity and a residual reduction of 20–45% of Cr(VI) was observed even after its breakthrough.  相似文献   
66.
Routine inspection is the most common form of highway bridge inspection to satisfy the requirements of the National Bridge Inspection Standards. The accuracy and reliability of documentation generated during these inspections are critical to the allocation of Department of Transportation construction, maintenance, and rehabilitation resources. Routine inspections are typically completed using only the visual inspection technique and rely heavily on subjective assessments made by bridge inspectors. In light of this, and given the fact that visual inspection may have other limitations that influence its reliability, the Federal Highway Administration initiated an investigation to examine the reliability of visual inspection as it is currently applied to bridges in the United States. This paper will summarize results from this study related to the accuracy and reliability of routine inspection documentation. A number of important conclusions were developed from the experimental study. Generally, it was found that all structural condition documentation is collected with significant variability. Specifically, 95% of primary element condition ratings for individual bridge components will vary within two rating points of the average and only 68% will vary within one point. Documentation generally collected to support condition ratings also has significant variability as exemplified by the number and types of field notes and photographs taken by inspectors. With respect to the use of element-level inspections, it was found that element usage was generally consistent with the Commonly Recognized Element Guide. However, there is significant variability in the condition state assignments of those elements and in some cases the condition states are not applied correctly to particular elements.  相似文献   
67.
Objective: A randomized trial assessed the effectiveness of a 2-level strategy for implementing evidence-based mental health treatments for delinquent youth. Method: A 2 × 2 design encompassing 14 rural Appalachian counties included 2 factors: (a) the random assignment of delinquent youth within each county to a multisystemic therapy (MST) program or usual services and (b) the random assignment of counties to the ARC (for availability, responsiveness, and continuity) organizational intervention for implementing effective community-based mental health services. The design created 4 treatment conditions (MST plus ARC, MST only, ARC only, control). Outcome measures for 615 youth who were 69% male, 91% Caucasian, and aged 9–17 years included the Child Behavior Checklist and out-of-home placements. Results: A multilevel, mixed-effects, regression analysis of 6-month treatment outcomes found that youth total problem behavior in the MST plus ARC condition was at a nonclinical level and significantly lower than in other conditions. Total problem behavior was equivalent and at nonclinical levels in all conditions by the 18-month follow-up, but youth in the MST plus ARC condition entered out-of-home placements at a significantly lower rate (16%) than youth in the control condition (34%). Conclusions: Two-level strategies that combine an organizational intervention such as ARC and an evidence-based treatment such as MST are promising approaches to implementing effective community-based mental health services. More research is needed to understand how such strategies can be used effectively in a variety of organizational contexts and with other types of evidence-based treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
68.
The current study evaluated the associations between externalizing psychopathology and marital adjustment in a combined sample of 1,805 married couples. We further considered the role of personality in these associations, as personality has been found to predict both the development of externalizing psychopathology as well as marital distress and instability. Diagnostic interviews assessed conduct disorder, adult symptoms of antisocial personality disorder, and alcohol dependence. Personality was assessed using the Multidimensional Personality Questionnaire. The Dyadic Adjustment Scale was used to measure marital adjustment. Results indicate that more externalizing psychopathology, greater negative emotionality, and lower communal positive emotionality were associated with reduced marital adjustment in both individuals and their spouses. Low constraint was associated with reduced marital adjustment for individuals but not for their spouses. Multivariate analyses indicated externalizing psychopathology continued to predict marital adjustment even when accounting for overlap with personality. These results highlight the importance of examining the presence of externalizing psychopathology and the personality attributes of both members of a dyad when considering psychological predictors of marital adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
69.
Childhood attachment, family environment, and adult social competencies were examined to explain the association between sexual abuse and eating disorders (EDs). Female college students (n?=?102) and female clients sexually abused in childhood (n?=?52) completed surveys retrospectively that assessed parental bonds, family environment, and sexual abuse, as well as current self-efficacy, social support, intimacy, adult attachment style, and ED symptoms. Client incest survivors had a higher ED rate (47%) than did sexually abused clients (22%), student incest survivors (24%), or nonabused students (17%). Significant associations were found between family environment, incest, social competencies, and eating disorders. Incest survivors had more dysfunctional families and lower social competencies than did nonabused women. Among incest survivors, those with the lowest levels of social competencies and poorest bonds with their mothers had more ED symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.

A dissimilar metal weldment consisting of SA508-309L-308L-304L is widely used in light-water nuclear reactors. These weldments demonstrate dissimilar susceptibility to stress corrosion cracking that are related to the microstructure, properties, and residual stress. In this work, microstructures, hardness, and the residual stress distribution of the dissimilar metal weldments were investigated, with the correlation of increased hardness in the heat-affected zone (HAZ) to the microstructure. 304L HAZ demonstrated similar grain morphology as the base material, and the increase in hardness was primarily attributed to the increased dislocation density. SA508 HAZ demonstrated a change of grain morphology resulting from the different peak temperatures and cooling rates. The increased hardness in the SA508 HAZ was attributed to the refined grain morphology, higher dislocation density, and higher number density of precipitates. A ~ 20–30-μm-wide martensitic zone formed at the fusion boundary of SA508-309L, where Cr-rich carbide precipitates were observed, with the average size and the number density of 44.1 ± 16.9 nm and 1.5 × 1021 m−3, respectively. Residual stress results demonstrated the largest tensile stress at 309L butter, indicating its high cracking susceptibility.

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