Redefining professional identity: the voice of a language teacher in a context of collaborative learning

Following a narrative and biographic approach, in this study, we present the case of an in-service language teacher and her professional learning trajectory in the context of the project ‘Languages and education: constructing and sharing training’. This project aimed at the construction of a collaborative teacher education context for learning and transformation of experiences, views and practices in language education, and involved teachers, teacher educators and researchers. Based on a single case study, the analysis tries to disclose the teacher’s discursive displacements as hints of professional transformation while she reinterprets the learning taking place in the collaborative education process. The signs of change are visible in the way she constructs meanings regarding her professional identity, re-identifies her mission as a language teacher and reconsiders her professional identity. Finally, we reflect upon how collaborative teacher education scenarios may foster teachers’ personal professional learning and renewed self-images.     

Numerical study of dc-biased ac-electrokinetic flow over symmetrical electrodes

This paper presents a numerical study of DC-biased AC-electrokinetic (DC-biased ACEK) flow over a pair of symmetrical electrodes. The flow mechanism is based on a transverse conductivity gradient created through incipient Faradaic reactions occurring at the electrodes when a DC-bias is applied. The DC biased AC electric field acting on this gradient generates a fluid flow in the form of vortexes. To understand more in depth the DC-biased ACEK flow mechanism, a phenomenological model is developed to study the effects of voltage, conductivity ratio, channel width, depth, and aspect ratio on the induced flow characteristics. It was found that flow velocity on the order of mm/s can be produced at higher voltage and conductivity ratio. Such rapid flow velocity is one of the highest reported in microsystems technology using electrokinetics.     

Detection of Misconceptions about Colour and an Experimentally Tested Proposal to Combat them

We study the misconceptions about colour that most people hold, determining the general phenomenological laws that govern them. Concept mapping was used to combat the misconceptions which were found in the application of a test specifically designed to determine these misconceptions, while avoiding the possible misleading inductions that could have arisen from the use of everyday language. In particular, care was taken to avoid the distorting effect that the use of the verb ‘to be’ applied to coloured objects could have on the responses. The misconceptions found were shown to have an internal consistency in the form of authentic mini-theories (implicit theories). We compared experimentally the results of two different teaching methods applied to combat these misconceptions. This study was conducted with 470 undergraduates of the University of Extremadura. We analysed the persistence over time of their learning made to overcome those misconceptions. The students were divided randomly into an experimental group (EG) and a control group (CG). To combat their misconceptions, EG were taught following a method based on the use of concept maps, and CG were taught following traditional teaching methods. The results of a pre-test and a post-test were compared for the two groups, finding statistically significant differences. The results allowed the principal working hypothesis to be accepted—concept maps are learning tools which foster conceptual change and allow misconceptions to be eradicated via meaningful learning maintained over time, i.e. EG acquired a relative long-lasting gain in learning that was superior to that acquired by CG.     

Teaching to write collaborative argumentative syntheses in higher education

Reading and Writing - Writing argumentative syntheses based on multiple sources implies integrating ideas from different, often conflicting, positions. This can promote more constructive learning,...