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161.
The concept of capacity has become increasingly important in discussions of working memory (WM), in so far as most models of WM conceptualize it as a limited-capacity mechanism for maintaining information in an active state, and as capacity estimates from at least one type of WM task—complex span—are valid predictors of real-world cognitive performance. However, the term capacity is also often used in the context of a distinct set of WM tasks, change detection, and may or may not refer to the same cognitive capability. We here develop maximum-likelihood models of capacity from each of these tasks—as well as from a third WM task that places heavy demands on cognitive control, the self-ordered WM task (SOT)—and show that the capacity estimates from change detection and complex span tasks are not correlated with each other, although capacity estimates from change detection tasks do correlate with those from the SOT. Furthermore, exploratory factor analysis confirmed that performance on the SOT and change detection load on the same factor, with performance on our complex span task loading on its own factor. These findings suggest that at least two distinct cognitive capabilities underlie the concept of WM capacity as it applies to each of these three tasks.  相似文献   
162.
A comprehensive family history is essential to identify patients at risk for hereditary cancer who could benefit from genetic counseling (GC). In a previous study, we observed a low occurrence of family history record (FHR) collection rate and GC referral among oncologists at our institution. The present work analyzes whether the implementation of a heredofamilial cancer unit (HFCU) would improve these parameters. We retrospectively compared the FHR rate in clinical records, National Cancer Institute (NCI) general criteria for hereditary cancer suspicion, GC referrals and FHR quality in two cohorts: cohort 1 (patients diagnosed before HFCU creation) and cohort 2 (after HFCU creation). Of 1,175 patients (590 cohort 1 and 585 cohort 2), FHRs were consigned in 27.3 % and 52.5 % of patients, respectively (p?<?0.001). The GC referral of patients with any NCI criterion was 13.6 % xin cohort 1 vs. 40.5 % in cohort 2 (p?<?0.001). FHR quality improved in terms of the total number of relatives (164 vs. 314, p?=?0.1, N.S.) and number of healthy relatives consigned (80 vs. 191, p?<?0.01). Nine mutations (6 BRCA, 1 MEN1, 2 Lynch), 4 unknown significance variants (all in BRCA) and 2 with no mutation were identified among patients referred from cohort 2. We conclude that the creation of a heredofamilial cancer unit has changed both FHR and GC referrals among oncologists at our institution, although continuous educational efforts are required.  相似文献   
163.
Microstructure and deformation mechanisms at a nanoindentation in the lamellar colony of high Nb containing TiAl alloy have been studied using the focused ion beam and the transmission electron microscopy. Considerable deformation twins are observed around the nanoindentation, and a strain gradient is generated. A continuous change in the bending angle of the lamellar structure can be derived, and a strain-induced grain refinement process is observed as various active deformations split the γ grains into subgrains. In addition to all possible deformation mechanisms (ordinary dislocation, super-dislocation and deformation twining) activated due to the heavy plastic deformation, a 6-layer hexagonal (6H) long-period stacking ordered structure is identified for the first time near the contact zone and is thought to be closely related to the glide of partial dislocations.  相似文献   
164.
The plastic stability of bimetals composed of a Ti-based metallic glass composite (MGC) and a pure titanium (PT) under tension has been investigated. The results reveal that the plastic stability of the MGC/PT bimetal is strongly dependent on the thickness fraction of the MGC: when the thickness fraction of the MGC decreases to a critical value, a homogeneous plastic deformation occurs in the MGC/PT bimetals, i.e. the strain localization and necking of the MGC is effectively suppressed. This unique phenomenon is explained using the normalized strain-hardening rate, and the quantitative relationship between the normalized strain-hardening rate of the MGC/PT bimetals and the thickness fraction of the MGC is thereby established.  相似文献   
165.
166.
ABSTRACT. The objective of the current study is to analyze the role of professional self-efficacy as a predictor of psychosocial well-being (i.e., burnout and engagement) following the Social Cognitive Theory of Albert Bandura (1997). Structural Equation Modeling was performed in a sample of secondary school teachers (n = 460) and users of Information and Communication Technology (n = 596). Results show empirical support for the predicting role that professional self-efficacy plays in the perception of challenge (i.e., mental overload) and hindrance demands (i.e., role conflict, lack of control, and lack of social support), which are in turn related to burnout (i.e., erosion process) and engagement (i.e., motivational process). Specifically, employees with more professional self-efficacy will perceive more challenge demands and fewer hindrance demands, and this will in turn relate to more engagement and less burnout. A multi-group analysis showed that the research model was invariant across both samples. Theoretical and practical implications are discussed.  相似文献   
167.
This article concerns the construct of lay situationism—an individual’s belief in the importance of a behavior’s context. Study 1 identified a 13-item Situationism Scale, which demonstrated good reliability and validity. In particular, higher situationism was associated with greater situation-control (strategies to manipulate the environment in order to avoid temptation). Subsequent laboratory studies indicated that people higher on the situationism subscales used greater situation-control by sitting farther from junk food (Study 2) and choosing to drink non-alcoholic beverages before a cognitive task (Study 3). Overall, findings provide preliminary support for the psychometric validity and predictive utility of the Situationism Scale and offer this individual difference construct as a means to expand self-regulation theory.  相似文献   
168.
169.
Journal of Behavioral Education - The time students spend actively engaged with instruction is positively correlated with their academic achievement (Dotterer and Lowe in J Youth Adolesc...  相似文献   
170.
The Body Esteem Scale (BES; Franzoi and Shields 1984) has been a primary research tool for over 30 years, yet its factor structure has not been fully assessed since its creation, so a two-study design examined whether the BES needed revision. In Study 1, a series of principal components analyses (PCAs) was conducted using the BES responses of 798 undergraduate students, with results indicating that changes were necessary to improve the scale’s accuracy. In Study 2, 1237 undergraduate students evaluated each BES item, along with a select set of new body items, while also rating each item’s importance to their own body esteem. Body items meeting minimum importance criteria were then utilized in a series of PCAs to develop a revised scale that has strong internal consistency and good convergent and discriminant validity. As with the original BES, the revised BES (BES-R) conceives of body esteem as both gender-specific and multidimensional. Given that the accurate assessment of body esteem is essential in better understanding the link between this construct and mental health, the BES-R can now be used in research to illuminate this link, as well as in prevention and treatment programs for body-image issues. Further implications are discussed.  相似文献   
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