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901.
The social class worldviews (social class beliefs, attitudes, and values) of 14 first-generation college students were investigated with qualitative interviews. Consensual qualitative research analysis revealed first-generation students’ perspectives on the development of their social class worldviews, the effect of these worldviews on their transitions to college, and vice versa. The students’ pre-college beliefs and values promoted hard work and college attendance as a means of financial success. The transition to college created disequilibrium in the social class worldviews of the students interviewed, who in turn responded by attempting to adapt to the new culture, emphasizing their social class background, or downplaying the role of social class in their lives altogether. College professionals working with first-generation students are encouraged to facilitate dialogues with first-generation students about their social class worldview and its impact on students’ engagement with the college community.  相似文献   
902.
We report a theoretical investigation on the control of wave-vector filtering (WVF) in a two-dimensional electron gas modulated by realistic magnetic barriers and δ-doping, which can be experimentally realised by depositing a ferromagnetic stripe on the surface of a GaAs/AlxGa1?xAs heterostructure and using atomic layer doping. Theoretical analysis demonstrates that a sizeable WVF effect still exists even if δ-doping is introduced into the device. Numerical calculation reveals that the WVF efficiency is related closely to the δ-doping. Thus, the WVF effect in a magnetic nanostructure can be conveniently manipulated by properly adjusting the weight and/or the position of the δ-doping, giving rise to a tunable momentum filter for nanoelectronics applications.  相似文献   
903.
In a 1-hour teaching interview, 20 children (aged 7 to 11) discovered how to tell whether objects might be made of the same material by using ratios of measures of weight and size. We examine progress in the children's reasoning about measurement and proportional relations, as well as design features of instruments, materials, and tasks crafted to enable such progress. Findings are discussed in light of theories and research about cognitive development and learning.  相似文献   
904.
Rare-earth (RE) elements are helpful in improving the mechanical properties of cemented carbides. In this work, the formation of Y2O3 in functionally graded cemented carbides is investigated using transmission electron microscopy. The results indicate that Y2O3 can stabilize the Co phase with the face-centred cubic structure (α-Co), since it has a cubic structure similar to the high-temperature Co phase. The α-Co phase has a higher plasticity than ε-Co, and this suggests a possible mechanism for the role of RE elements in toughening cemented carbides.  相似文献   
905.
关于内隐学习能否获得底层的抽象规则,研究一直存在争议。该研究通过有效地控制组块和重复结构等表面特征,并操纵规则所在背景的变异性大小,考察了两种汉语声调对称规则——逆行和倒映的内隐学习。结果发现,只有在背景变异较大时,被试才能够超越组块等表面特征,进而无意识地获得汉语声调对称规则的结构知识。该研究证明内隐学习能够获得抽象规则,并从背景变异性效应的角度为考察该问题提供了新的视角。  相似文献   
906.
The purpose of the current study was to examine the influence proactive personality on innovative work behavior in teaching profession and investigate the potential mediating effects of affective states and creative self-efficacy on this relationship. Proactive Personality Scale, Positive and Negative Affect Schedule, Creative self-efficacy Scale and Teachers’ Innovative Work Behavior Scale were administered to 352 primary and middle school teachers in China. Results showed that proactive personality was significantly positively associated with teachers’ innovative work behavior. Furthermore, mediation analyses revealed that the impact of proactive personality on teachers’ innovative work behavior were simply mediated by positive affect and creative self-efficacy and sequential mediated by positive affect–creative self-efficacy and negative affect–creative self-efficacy. These findings provide a new perspective in understanding the intervening mechanisms underlying proactive personality on innovative work behavior. The possible explanations and limitations are discussed.  相似文献   
907.
Liu D  Wang Y  Zhou X 《Acta psychologica》2011,138(3):397-404
Previous studies demonstrate that attentional selection can be object-based, in which the object is defined in terms of Gestalt principles or lexical organizations. Here we investigate how attentional selection functions when the two types of objects are manipulated jointly. Experiment 1 replicated Li and Logan (2008) by showing that attentional shift between two Chinese characters is more efficient when they form a compound word than when they form a nonword. Experiment 2A presented characters either alone or within rectangles (Egly, Driver, & Rafal, 1994) and the characters in a rectangle formed either a word or a nonword. Experiment 2B differed from Experiment 2A in that the two characters forming a word were in different rectangles. Experiment 3A presented the two characters of a word either within a rectangle or in different rectangles. Experiment 3B used the same design as Experiment 3A but presented stimuli of different types in random orders, rather than in blocks as in Experiments 2A, 2B and 3A. In blocked presentation, detection responses to the target color on a character were faster when this character and the cue character formed a word than when they did not, and the size of this lexical-based object effect did not vary according to whether the two characters were presented alone or within or between rectangles. In random presentation, however, the lexical-based object effect was diminished when the two characters of a word were presented in different rectangles. Overall, these findings suggest that the processes that constrain attention deployment over conjoined objects can be strategically adjusted.  相似文献   
908.
The present research examined the effectiveness of a cognitive-behavioral therapy (CBT) based intervention program, FRIENDS, for children from grades 4 to 6, using random assignment at the school-level and an attention-control design in two longitudinal studies. The first study targeted children with anxiety symptoms (N = 191, mean age = 10.1) as screened with self, parent, and teacher-reports; the second study took a universal approach with full classrooms of children participating (N = 253, mean age = 9.8). The results showed no intervention effect in both studies, with children’s anxiety symptoms decreasing over time regardless of whether they were in the story-reading (attention control) or FRIENDS condition. The findings also indicated that girls reported a higher level of anxiety than boys and children in higher grades reported lower anxiety relative to younger children in both studies. In addition, similar patterns were found using a subgroup of children with high-anxiety symptoms from both studies.  相似文献   
909.
The use of covariates is commonly believed to reduce the unexplained error variance and the standard error for the comparison of treatment means, but the reduction in the standard error is neither guaranteed nor uniform over different sample sizes. The covariate mean differences between the treatment conditions can inflate the standard error of the covariate‐adjusted mean difference and can actually produce a larger standard error for the adjusted mean difference than that for the unadjusted mean difference. When the covariate observations are conceived of as randomly varying from one study to another, the covariate mean differences can be related to a Hotelling's T2. Using this Hotelling's T2 statistic, one can always find a minimum sample size to achieve a high probability of reducing the standard error and confidence interval width for the adjusted mean difference.  相似文献   
910.
Background. Methods for teaching thinking may be described as out‐of‐context or infusion. Both approaches have potential to raise students’ general cognitive processing ability and so raise academic achievement, but each has disadvantages. Aims. To describe and evaluate a theory‐based learn to think (LTT) curriculum for primary school students, which draws on the strengths of both out‐of‐context and infusion approaches. Sample. One‐hundred and sixty‐six students in three classes of Grade 1 (6+ years old), Grade 2 (7+ years old), and Grade 3 (8+ years old) in a primary school in Shanxi province, China, randomly ascribed to experimental (90) and control (76) groups. Methods. All students were pre‐tested for non‐verbal intelligence and academic achievement. Experimental students followed the LTT curriculum (one activity every 2 weeks) for 4 school years. All were post‐tested on three occasions for thinking ability and four times for academic achievement. Results. Grade 1 and Grade 2 students showed effects of LTT from 1 year after their start and increasing: on thinking ability d= .78–1.45; on Chinese d= .68–1.07; on maths .58–.87. Grade 3 students showed effects from 6 months after their start: on thinking ability .90–1.37; Chinese .77–1.32; maths .65–1.29. The effects were concentrated in students in the middle band of initial ability. Conclusions. A curriculum for teaching thinking based on a structured theoretical model that combines elements of out‐of‐context and infusion methods has been shown to have long‐term far transfer effects on students’ thinking ability and academic achievement. More work is needed to meet the needs of a wider range of abilities.  相似文献   
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