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991.
This paper investigates the noticing of six Chinese mathematics prospective teachers (PSTs) when looking at a procedural error and responding to three specific tasks related to that error. Using video clips of one student’s procedural error consisting of exchanging the order of coordinates when applying the distance formula, some variation was found in how PSTs attended to, interpreted, and responded to this error. A more important finding is represented by the inconsistent responses that individual PSTs provided to the three related tasks. This finding suggests that, to some extent, prior learning experience, beliefs, and orientations inform what PSTs notice. But the finding also suggests the centrality of selecting tasks that provide accurate representations of PSTs’ emerging professional noticing. Implications for teacher educators are discussed.  相似文献   
992.
This study reports the development and evaluation of a Turkish-language version of three positive psychology assessments for use in clinical, education and research settings with Turkish-speaking individuals. A multistage translation of the Brief Resilience Scale (BRS; Smith et al. in International Journal of Behavioral Medicine, 15, 194–200, 2008), the General Mattering Scale (GMS; Marcus 1991) and the Short Grit Scale (GS; Duckworth & Quinn in Journal of Personality Assessment, 91, 166–174. doi:10.1080/00223890802634290, 2009) is detailed, as well as the procedure used to evaluate the internal structure of the translated assessments. The results yielded from data of 268 participants indicated factor structures ranging from acceptable to robust model fit for the BRS, GMS, and GS. Implications for counseling practice and future research are discussed.  相似文献   
993.
The aim of this study was to research the changes in cytotoxicity and antibacterial properties after silver nanoparticles (AgNPs) were incorporated into the surface coating of dental alloys. AgNPs were attached to cobalt chromium alloys and pure titanium using a hydrothermal method, according to the reaction: AgNO3+NaBH4→ Ag+1/2H2+1/2B2H6+NaNO3. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to evaluate the cytotoxicity of the alloys when in contact with osteogenic precursor cells (MC3T3-E1) from mice and mesenchymal stem cells (BMSC) from rats. The antibacterial properties of dental alloys incorporating three different concentrations (10, 4, and 2 μmol/L) of AgNPs were tested on Staphylococcus aureus (SA) and Streptococcus mutans (MS). High cytotoxicity values were observed for all dental alloys that contained 0% of AgNPs (the control groups). The incorporation of AgNPs reduced cytotoxicity values. No significant difference was observed for antibacterial performance when comparing dental alloys containing AgNPs to the respective control groups. The results demonstrated that the cobalt chromium alloys and pure titanium all had cytotoxicity to MC3T3-E1 and BMSC and that the incorporation of AgNPs could reduce this cytotoxicity. The concentrations of AgNPs adopted in this study were found to have no antibacterial action against SA or MS.  相似文献   
994.
This meta-analysis examined research on the effects of self-regulated learning scaffolds on academic performance in computer-based learning environments from 2004 to 2015. A total of 29 articles met inclusion criteria and were included in the final analysis with a total sample size of 2648 students. Moderator analyses were performed using a random effects model that focused on the three main areas of scaffold characteristics (including the mechanism, functions, delivery forms, mode, and number of scaffolds; how to promote self-regulated learning by scaffolds); demographics of the selected studies (including sample groups, sample size, learning domain, research settings, and types of computer-based learning environments); and research methodological features (including research methods, types of research design, types of organization for treatment, and duration of treatment). Findings revealed that self-regulated learning scaffolds in computer-based learning environments generally produced a significantly positive effect on academic performance (ES = 0.438). It is also suggested that both domain-general and domain-specific scaffolds can support the entire process of self-regulated learning since they demonstrated substantial effects on academic performance. Different impacts of various studies and their methodological features are presented and discussed.  相似文献   
995.
Inclusive schooling policy: An educational detective story?   总被引:1,自引:0,他引:1  
Since the publication of the Salamanca statement (UNESCO 1994), inclusive schooling has formed a growing part of the deliberations of the special education community. Inclusive schooling research in Australia in the main continues to reproduce traditions of the special education field, emphasising the dominant psychological perspectives that have been superimposed on inclusive education discourses. At the fifth International Congress of Special Education (ISEC 2000) held in Manchester, ‘the death knell of the concept of special education’ (ISEC 2000) was announced. The concept proposed by Mike Oliver, Professor of Disability Studies at the University of Greenwich, asserts an end to understandings of diversity dependent on medical, psychological and charity-based discourses. From a recent study of inclusive schooling policy, and drawing from poststructuralist methodology, I suggest an approach to research, policy development and practice that questions traditionalist theorising in the special education field. Reflecting on the implementation of the Inclusion of Students with Disabilities Policy (DECCD 1995) in the Tasmanian government school system, I outline my alignment with Oliver’s view and highlight how questions of epistemology and reconstructions of research methodologies are central to rethinking understandings of difference. I also illustrate a methodological orientation that offers possibilities for a different science to take place, thereby understanding diversity as multiple and contradictory — and beyond the single ‘detective story’ (Gough 1998) of the medical, psychological and charity-based discourses that circulate in schools as the populist conceptions of ‘inclusion’.  相似文献   
996.
Writing is a task that entails high cognitive and linguistic efforts, especially when producing academic texts. Academic language might be one of the factors influencing the quality of written texts, given that prior research has shown its impact on reading comprehension. The purpose of this study is to examine the contribution of Spanish Core Academic Language Skills (S-CALS) and academic vocabulary to the quality of written argumentation and explanation. For this study, 126 Chilean 8th grade students produced an argumentative text and an explanatory text about the same topic. In addition, their academic vocabulary was assessed with the S-AVoc-T test and their CALS with the S-CALS-I test. Results show that both CALS and academic vocabulary are significantly and positively correlated with both writing tasks. Even though these instruments make different contributions to the predictive models in each discursive genre, a Principal Component Analysis revealed that the model that best explains writing quality are those which combine both language variables, namely Spanish Core Academic Language and Vocabulary Skills (S-CALVS). In argumentation, the S-CALVS model explains 29% of the variance, after controlling by gender. In contrast, in explanation, S-CALVS explains 35% of the variance. It is concluded that it is relevant to develop situated writing in each discursive genre and, upon that basis, to work with both CALS and academic vocabulary, because they have a specific impact on academic texts writing.  相似文献   
997.
Based on five scheduling types and their QoS requirements defined in IEEE 802.16e specification, this paper proposes a new scheduring algorithm for non-real-time or real-time multimedia services. Taking the performances of efficiency, fairness and complexity into consideration, the proposed algorithm enhances the efficiency of air interface resource at the expense of the short-time unfairness, but ensures the long-time fairness. Moreover, the proposed algorithm introduces an efficient QoS assurance mechanism, which implements the functions of congestion control, queuing management and traffic management. The simulation results based on a simplified traffic model show that the proposed algorithm guarantees better performances of efficiency and fairness than conventional algorithms, without increasing the algorithm complexity. Especially on the occasion of heavy-traffic requirement, the performance of efficiency and fairness can be improved by 50% at most.  相似文献   
998.
Reinforced concrete (RC) columns lacking adequately detailed transverse reinforcement do not possess the necessary ductility to dissipate seismic energy during a major earthquake without severe strength degradation. In this paper, a new retrofit method, which utilized fiber-reinforced plastics (FRP) confinement mechanism and anchorage of embedded bars, was developed aiming to retrofit non-ductile large RC rectangular columns to prevent the damage of the plastic hinges. Carbon FRP (CFRP) sheets and glass FRP (GFRP) bars were used in this test, and five scaled RC columns were tested to examine the function of this new method for improving the ductility of columns. Responses of columns were examined before and after being retrofitted. Test results indicate that this new composite method can be very effective to improve the anti-seismic behavior of non-ductile RC columns compared with normal CFRP sheets retrofitted column.  相似文献   
999.
Hamiltonian system for the problem on clamped Mindlin plate bending was established by introducing the dual variables for the generalized displacements in this letter. By separation of variables, the transverse eigen-problem was derived based on the sympletic geometry method. With the solved sympletic eigen-values, the generalized sympletic eigen-solution was derived through eigenfunction expansion. An example of plate with all edges clamped was given. The sympletic solution system was worked out directly from the Hamiltonian system. It breaks the limitation of traditional analytic methods which need to select basis functions in advance. The results indicate that the sympletic solution method could find its more extensive applications.  相似文献   
1000.
Oral Cancer is one of the five leading sites of cancer in Indian population. The circulating immune complexes were investigated in 100 serum samples of 60 oral cancer patients having different grades of the disease and 40 patients with precancerous lesions obtained from Nair Hospital Dental collage, Mumbai. The results obtained were compared with those of group of 40 healthy blood donors. Elevated levels of Circulating Immune Complexes were observed in oral cancer patients and patients with oral precancerous lesions. 92% positive samples were observed in well differentiated squamous cell carcinoma whereas 100% positive samples were observed in both moderately and poorly differentiated squamous cell carcinoma. Oral leukoplakia and oral submucous fibrosis showed 15% and 90% positivity respectively. Increased level of Circulating Immune complexes in high grade tumor suggest that Circulating Immune complexes is likely to contribute in evaluating the degree of malignancy, but follow up study is needed to draw any conclusion regarding it's prognostic role  相似文献   
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