The Use of Representations and Argumentative and Explanatory Situations

This paper discusses the use of non-verbal representations in a modelling-based science teaching context, in which argumentative and explanatory situations occur. More specifically, we analyse how the students and teacher use representations in their discourse in modelling activities, and we discuss the relationships between the functions of these representations and the demands of the explanatory and argumentative situations that exist in that classroom. The data were collected by video recording all the classes in which a teaching sequence about intermolecular interactions was used—a topic which the students had not previously studied. In the activities, the students had to create, express, test, and discuss models in order to understand the difference between intermolecular and interatomic interactions, as well as their influences on the properties of substances. Initially, we selected excerpts of the recorded classes in which a non-verbal representation was used. Then, we used criteria to identify the argumentative and explanatory situations (previously defined), and we created categories for the functions of the representations that were used in order to analyse all the identified situations. The analysis supports conclusions indicating the relevance of the use of non-verbal representations in the construction, use, and defence of explanations. As the defence of explanations was the main context in which argumentative situations occurred in this study, our conclusions also indicate the contribution that representations make towards changing the status of the students' explanations.     

The Educational Challenge of Unraveling the Fantasies of Ontological Security

In this article we address the current context of intensified racialized state securitization by tracing its roots to the naturalized colonial architectures of everyday modern life—which we present through the metaphor of “the house modernity built.” While contemporary crises are often perceived to derive from external threats to the house, we argue that in fact these crises are a product of the violent and unsustainable practices that are required in order to build and sustain the house itself. As the structural integrity of the house increasingly comes under strain, there are different possible responses, three of which we review here. We conclude by asking what kind of education might enable us to imagine and practice alternative formations of existence in a context where the house appears to be crumbling, and, indeed, has always been a fantasy.     

Engaging Students in Guided Science Inquiry Discussions: Elementary Teachers’ Oral Strategies

This study explores how elementary teachers perceive and use engaging oral strategies (i.e., manners of speaking that encourage students to participate and become engaged in science discussions). It is reported that the strategies employed as well as their frequency varied substantially depending upon on the teachers’ grade level and perceptions. While a kindergarten teacher viewed such strategies negatively and employed only a few figurative directives, fourth-grade teachers viewed them positively, frequently resorting to a variety of speech figures, parallel repetition and engaging questions. It is argued that teachers’ engaging oral strategies are multifunctional, serving important social and cognitive functions.     

Development of Pre-Service Mathematics Teachers' Professional Knowledge and Identity in Working with Information and Communication Technology

This paper describes the workundertaken in a course in communication andinformation technology in a pre-service programfor secondary school mathematics teachers. Thiscourse aimed to help pre-service teachersdevelop a positive attitude regarding ICT anduse it confidently. It focused on theexploration of educational software and of theInternet's potential as a means of research andproduction of web sites. We discuss how thepre-service mathematics teachers evaluate theirwork concerning their commitment, difficultiesthey found, learning they identified, andpersonal relationship. We also analyse theeffects of the course on the development oftheir professional knowledge and identity.     

Extending the understanding of mobile banking adoption: When UTAUT meets TTF and ITM

Mobile banking (mBanking) enables customers to carry out their banking tasks via mobile devices. We advance the extant body of knowledge about mBanking adoption by proposing a model for understanding the importance and relationship between the user perception of mBanking, initial trust in mBanking services, and the fit between the technology and mBanking task characteristics. We synergistically combine the strengths of three IS theories – task technology fit (TTF) model, unified theory of acceptance and usage of technology (UTAUT), and initial trust model (ITM). The model was tested in a study conducted in Portugal, one of the European Union (EU) countries with the highest mobile phone adoption. Based on the sample of 194 individuals we applied partial least squares (PLS) to test the conceptual model propose. The path significance levels were estimated using the bootstrapping method (500 resamples). The study found that facilitating conditions and behavioral intentions directly influence mBanking adoption. Initial trust, performance expectancy, technology characteristics, and task technology fit have total effect on behavioral intention. The paper offers valuable insights to decision-makers involved in the implementation and deployment of mBanking services. For researchers, the paper highlights the usefulness of integrating TTF, UTAUT and ITM in the development of a decision support framework to study the adoption of new technologies.     

Functional torque ratios and torque curve analysis of shoulder rotations in overhead athletes with and without impingement symptoms

In this study, we evaluated the peak torque, functional torque ratios, and torque curve profile of the shoulder rotators in overhead athletes with impingement symptoms so as to examine possible alterations in response to sports training and shoulder pain. Twenty-one overhead athletes with impingement symptoms were compared with 25 overhead athletes and 21 non-athletes, none of whom were symptomatic for impingement. The participants performed five maximal isokinetic concentric and eccentric contractions of medial and lateral shoulder rotations at 1.57 rad · s(-1) and 3.14 rad · s(-1). Isokinetic peak torque was used to calculate the eccentric lateral rotation-to-concentric medial rotation and the eccentric medial rotation-to-concentric lateral rotation ratios. An analysis of the torque curve profiles was also carried out. The eccentric lateral rotation-to-concentric medial rotation torque ratio of asymptomatic athletes was lower than that of non-athletes at both test velocities. The concentric medial rotation isokinetic peak torque of the asymptomatic athletes, at 3.14 rad · s(-1), was greater than that of the non-athletes, and the peak appeared to occur earlier in the movement for athletes than non-athletes. These findings suggest that there may be adaptations to shoulder function in response to throwing practice. The eccentric medial rotation-to-concentric lateral rotation torque ratio was altered neither by the practice of university-level overhead sports nor impingement symptoms.