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181.
Early Childhood Education Journal - Young children’s ideas of fairness have been studied in a range of laboratory settings with findings that children see fairness as equal distribution of...  相似文献   
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Instructional design (ID) models have been developed to promote understandings of ID reality and guide ID performance. As the number and diversity of ID practices grows, implicit doubts regarding the reliability, validity, and usefulness of ID models suggest the need for methodological guidance that would help to generate ID models that are relevant and appropriate to the ever-changing design challenges in our world. Because the construction of an ID model involves an intricate externalization of unique sets of design experiences as well as a logical synthesis of relevant research, the purpose of this study was to formulate a methodological framework for ID model development. Through the analysis of 20 selected studies, four critical dimensions and ten synthesized procedures for constructing ID models were formulated. The resulting framework is intended to provide a useful theoretical and practical contribution to the field of ID.  相似文献   
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In two dimensions (2D), representations associated with slopes are seen in numerous forms before representations associated with derivatives are presented. These include the slope between two points and the constant slope of a linear function of a single variable. In almost all multivariable calculus textbooks, however, the first discussion of slopes in three dimensions (3D) is seen with the introduction of partial derivatives. The nature of the discussions indicates that authors seem to assume that students are able to naturally extend the concept of a 2D slope to 3D and correspondingly it is not necessary to explicitly present slopes in 3D. This article presents results comparing students that do not explicitly discuss slopes in 3D with students that explicitly discuss slopes in 3D as a precursor to discussing derivatives in 3D. The results indicate that students may, in fact, have significant difficulty extending the concept of a 2D slope to a 3D slope. And that the explicit presentation of slopes in 3D as a precursor to the presentation of derivatives in 3D may significantly improve student comprehension of topics of differentiation in multivariable calculus.

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This study examines key school reform policies and outcomes of the USA and Korea over the past three decades from comparative perspectives. Since the two nations’ unique educational problems brought divergent educational reform paths—standardization versus differentiation, high-stakes testing versus individualized assessment, and centralization versus decentralization—the study tracks international policy benchmarking efforts and potential impact on educational convergence. The study employs mixed methods, including the content analysis of research and media documents and the trend analysis of TIMSS and PISA datasets. The results indicate that, despite significant changes in policy discourse, the gaps between Korea and the USA in student math achievement and school climates did not narrow. The policy lessons from these cases and the issues of international education benchmarking are discussed.  相似文献   
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Majority opinions are often observed in the process of social interaction in online communities, but few studies have addressed this issue with empirical data. To identify an appropriate theoretical lens for explaining majority opinions in online environments, this study investigates the skewness statistic, which indicates how many “Likes” are skewed to major comments on a Facebook post; 3489 posts are gathered from the New York Times Facebook page for 100 days. Results show that time is not an influential factor for skewness increase, but the number of comments has a logarithmic relation to skewness increase. Regression models and Chow tests show that this relationship differs depending on topic contents, but majority opinions are significant in overall. These results suggest that the bandwagon effect due to social affordance can be a suitable mechanism for explaining majority opinion formation in an online environment and that majority opinions in online communities can be misperceived due to overestimation.  相似文献   
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ObjectivePrimary tumor treatment through surgical resection and adjuvant therapy has been extensively studied, but there is a lack of effective strategies and drugs for the treatment of tumor metastases. Here, we describe a functional product based on a combination of compounds, which can be used as an adjuvant therapy and has well-known mechanisms for inhibiting cancer metastases, improving anti-cancer treatment, and enhancing immunity and antioxidant capacity. Our designed combination, named MVBL, consists of four inexpensive compounds: L-selenium-methylselenocysteine (MSC), D-‍α‍-tocopheryl succinic acid (VES), β‍-carotene (β‍-Ca), and L-lysine (Lys).MethodsThe effects of MVBL on cell viability, cell cycle, cell apoptosis, cell migration, cell invasion, reactive oxygen species (ROS), and paclitaxel (PTX)-combined treatment were studied in vitro. The inhibition of tumor metastasis, antioxidation, and immune enhancement capacity of MVBL were determined in vivo.ResultsMVBL exhibited higher toxicity to tumor cells than to normal cells. It did not significantly affect the cell cycle of cancer cells, but increased their apoptosis. Wound healing, adhesion, and transwell assays showed that MVBL significantly inhibited tumor cell migration, adhesion, and invasion. MVBL sensitized MDA-MB-231 breast cancer cells to PTX, indicating that it can be used as an adjuvant to enhance the therapeutic effect of chemotherapy drugs. In mice, experimental data showed that MVBL inhibited tumor metastasis, prolonged their survival time, and enhanced their antioxidant capacity and immune function.ConclusionsThis study revealed the roles of MVBL in improving immunity and antioxidation, preventing tumor growth, and inhibiting metastasis in vitro and in vivo. MVBL may be used as an adjuvant drug in cancer therapy for improving the survival and quality of life of cancer patients.  相似文献   
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ABSTRACT

Objective: Memory loss affects a large proportion of older adults. Research indicates a positive association between memory training and better memory performance as people age. However, studies on specific memory training using an experimental design are limited. This study explored whether memory training has improved memory performance in a group of older adults.

Method: A convenience sample of 48 participants was recruited from two communities. Disregarding dropouts, this left 23 experimental (mean age = 65.4 ± 6.0, range = 56–80) and 19 control participants (mean age = 64.5 ± 4.9, range: 57–72). The intervention consisted of 60-min classes held on a weekly basis continuing for 8 weeks. The class session was held after a 1-h exercise class and before a 1-h session of cognitive games. The pre–post objective memory performances, including associative, list, text, place, grocery learning, and transfer-effect of daily event memory (ecology validity), were examined to determine whether the intervention was effective.

Results: Intragroup: With Wilcoxon test, the findings showed that the intervention of both the list and place learning had significant differences for the experimental group, but not for the control group. Intergroup: The main effects were found for the associative and text learning. The mixed design ANOVA indicated that there is an interaction (time x group) on the dependent variable of the place learning test. Daily events memory: We found within group that the pre–post differences were significant for the experimental group but not for the control group.

Conclusion: The study showed that memory training can help older adults to ameliorate memory loss problems and these findings deserve more attention.  相似文献   
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