8 research outputs found

    Exploring pre-service teachers’ justifications for one-to-one technology use in schools: Implications for initial teacher education

    Get PDF
    peer-reviewedSet against the backdrop of a succession of educational technology policies in Ireland, influenced by international discourses, this study aimed to explore how Irish pre-service teachers justify the use of mobile technologies in schools. In order to achieve this, 23 pre service teachers were presented with a vignette that asked them to justify the use of a one-to one tablet initiative in school. The research found that pre-service teachers tended to justify the initiative, as they saw the increasing technification of schools and society as an inevitable process. In addition, they presented pragmatic reasons for using the technology rather than highlighting their educational/pedagogic value. This study points to the need to challenge pre-service teachers’ innovation-centric and techno-centric attitudes towards technology use. It also highlights the need for teacher educators, as a whole, to take a more active role in addressing this issue in teacher education programme

    The complex bet promoters of Escherichia coli: regulation by oxygen (ArcA), choline (BetI), and osmotic stress.

    No full text
    The bet regulon allows Escherichia coli to synthesize the osmoprotectant glycine betaine from choline. It comprises a regulatory gene, betI, and three structural genes: betT (choline porter), betA (choline dehydrogenase), and betB (betaine aldehyde dehydrogenase). The bet genes are regulated by oxygen, choline, and osmotic stress. Primer extension analysis identified two partially overlapping promoters which were responsible for the divergent expression of the betT and betIBA transcripts. The transcripts were initiated 61 bp apart. Regulation of the promoters was investigated by using cat (chloramphenicol acetyltransferase) and lacZ (beta-galactosidase) operon fusions. Mutation of betI on plasmid F'2 revealed that BetI is a repressor which regulates both promoters simultaneously in response to the inducer choline. Both promoters remained inducible by osmotic stress in a betI mutant background. On the basis of experiments with hns and hns rpoS mutants, we conclude that osmoregulation of the bet promoters was hns independent. The bet promoters were repressed by ArcA under anaerobic growth conditions. An 89-bp promoter fragment, as well as all larger fragments tested, which included both transcriptional start points, displayed osmotic induction and BetI-dependent choline regulation when linked with a cat reporter gene on plasmid pKK232-8. Flanking DNA, presumably on the betT side of the promoter region, appeared to be needed for ArcA-dependent regulation of both promoters
    corecore