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2008年11月,团购网站Groupon在美国成立——其命名由团体(group)和优惠券(coupon)合并而来——网上团购风马上席卷全美,而今更在全世界遍地开花。团购是继偷菜和微博之后又一个成为国人现实生活一部分的网络新生事物,在繁荣发展之余也产生了不少消费纠纷。3·15临近,小编提醒各位团友:团购有风险,点击要谨慎!     

An Embedded and Embodied Cognition Review of Instructional Manipulatives

Recent literature on learning with instructional manipulatives seems to call for a moderate view on the effects of perceptual and interactive richness of instructional manipulatives on learning. This “moderate view” holds that manipulatives’ perceptual and interactive richness may compromise learning in two ways: (1) by imposing a very high cognitive load on the learner, and (2) by hindering drawing of symbolic inferences that are supposed to play a key role in transfer (i.e., application of knowledge to new situations in the absence of instructional manipulatives). This paper presents a contrasting view. Drawing on recent insights from Embedded Embodied perspectives on cognition, it is argued that (1) perceptual and interactive richness may provide opportunities for alleviating cognitive load (Embedded Cognition), and (2) transfer of learning is not reliant on decontextualized knowledge but may draw on previous sensorimotor experiences of the kind afforded by perceptual and interactive richness of manipulatives (Embodied Cognition). By negotiating the Embedded Embodied Cognition view with the moderate view, implications for research are derived.     

How do teachers perceive cheating students? Beliefs about cues to deception and detection accuracy in the educational field

The present study explores how well teacher trainees can detect liars. Moreover, a new method was applied to investigate beliefs that teacher trainees hold about liars. The results indicate that, overall, teacher trainees were not better than chance in detecting true and invented stories. Generally, participants reported to have used only a few cues for their credibility judgment, where most of these self-reported cues are stereotypical and invalid deception cues (e.g., gaze aversion). Further analyses with a Brunswikian lens model showed that the self-reported cues were good predictors of their credibility judgment but only poorly predictive for the objective truth/lie status of the statement. Practical implications of the results are discussed.     

Improved Feistel-based ciphers for wireless sensor network security

Wireless sensor networks （WSNs） are exposed to a variety of attacks. The quality and complexity of attacks are rising day by day. The proposed work aims at showing how the complexity of modern attacks is growing accordingly, leading to a similar rise in methods of resistance. Limitations in computational and battery power in sensor nodes are constraints on the diversity of security mechanisms. We must apply only suitable mechanisms to WSN where our approach was motivated by the application of an improved Feistel scheme. The modified accelerated-cipher design uses data-dependent permutations, and can be used for fast hardware, firmware, software and WSN encryption systems. The approach presented showed that ciphers using this approach are less likely to suffer intrusion of differential cryptanalysis than currently used popular WSN ciphers like DES, Camellia and so on.     

Students’ Views of Design in an Engineering Design-Based Science Curricular Unit

Recent reforms in science education have supported the inclusion of engineering and their practices in K-12 curricula. To this end, many classrooms have incorporated engineering units that include design challenges. Design is an integral part of engineering and can help students think in creative and interdisciplinary ways. In this study, we examined students’ conceptions of design during and after participation in a design-based science curriculum unit. Our study was guided by the following research question: What are students’ views of design after participation in an engineering design-based science curriculum unit and how are these views reflected in their enactment throughout the unit? Using a qualitative approach, we examined students’ conversations throughout the enactment of the curriculum and interviews conducted after the completion of the unit. We found that students had complex and diverse views of design, and these views were reflected in their group discussions throughout the curriculum and design challenge. Students most frequently expressed design as learning and as a process of integration into a coherent whole. These aspects of design were also frequently observed in students’ conversations during the unit. Interestingly, we found evidence of students demonstrating several aspects of design throughout the curriculum that were not explicitly expressed during the student interviews. Taken together, these findings support the complex nature of design as seen at the middle school level.

     

The connection between phonological,syntactic and semantic skills and children’s reading and spelling

In recent years two radically different views have dominated discussions about the way in which children learn to read and write. The first view is that the crucial hurdle in learning to read is the discovery of how to do the correct phonological analysis. The second view is that the crucial factor is the use of context, and that children use what they know about the meaning — and particularly the semantics and the syntax — of the passages that they are reading to help them decipher and learn about difficult written words. Learning to read is ‘a psycholinguistic guessing game’ according to this view and children set about it in much the same way as they set about learning to speak. Thus according to the first view children’s semantic and syntactic skills will determine their progress in reading and according to the second it will be their phonological skills. We present longitudinal evidence about a group of children in their first year at school which shows that both kinds of skill do play a part, but that they make entirely different contributions. Semantic and syntactic skills determine how well children make use of the context of what they are reading. Phonological skills affect their use of letter-sound relationships.     

Experiences of mentorship with academic staff doctoral candidates at a south african university

Given the growing emphasis on academic research output and the challenges encountered in expediting completion of doctoral studies especially, mentorship is increasingly being utilised as a capacity development strategy for supporting scholars to complete post-graduate studies. This article reports on a mentorship project aimed at academic staff enrolled for doctoral studies in a health sciences faculty at a South African university, based on reflections drawn from annual feedback from the mentees and the annual report of the mentor, as well as a focus group conducted with mentees by an independent researcher. Participants found the mentorship, with its combination of individual and group meetings, as well as regular residential writing retreats, to be extremely helpful. A number of key features that enable the mentorship process emerged, and issues relating to supervision and mentorship were highlighted, especially regarding power dynamics.     

The effects of constructivist learning environments: a commentary

This special issue on the effects of constructivist learning environments is based on a symposium organized during the last annual meeting of the American Educational Research Association in Chicago. The studies in this issue not only provide an overview of the multitude of forms a constructivist learning environment can take, they also provide the reader with an overview of recent advances in this domain of research. The present discussion article provides a critical reflection on the studies in this special issue and tries to identify their prospects and limitations.     

Using critical race theory to analyze science teachers culturally responsive practices

Culturally responsive science teaching is using knowledge about the culture and life experiences of students to structure learning that is conducive to their needs. Understanding what teachers need to prepare them to be culturally responsive is a matter of continuous debate. As the focus of multicultural education ventures farther away from its roots, advocating the civil rights of historically oppressed groups, concerns about the gravity of racial inequity on schooling continues. How will this shift in focus influence teachers’ capacity to accommodate students’ needs resulting from racial inequities in this society, particularly African American students? What knowledge is essential to their effectiveness? This qualitative study examined the instructional practices of two effective middle school science teachers deemed culturally responsive by their administrator on the basis of classroom observations, students’ responses and standardized assessment results. Both teachers’ classrooms consisted primarily of African American students. Grounded theory was used to analyze the teachers’ beliefs and practices in order to identify existing commonalties. Critical race theory was used to identify whether there was any influence of the students’ racial identities on the teachers’ beliefs and practices. The analysis reveals that the teachers’ beliefs and practices were informed by their critical awareness of social constraints imposed upon their African American students’ identities. These findings communicate the significance of sociocultural awareness to informing the teachers’ instruction, as well as their strategies for managing the varying dynamics occurring in their classrooms. It can be deduced from the findings that an understanding of racial inequities is crucial to the development of sociocultural awareness, and is the foundation for the culturally responsive dispositions and practices of these middle school science teachers.