Milk lactate determination with a rotating bioreactor based on an electron transfer mediated by osmium complexes incorporating a continuous-flow/stopped-flow system

The high sensitivity that can be attained using a bienzymatic system and mediated by the redox polymer [Os(bpy)₂ClPyCH₂NHpoly(allylamine)] (Os-PAA), has been verified by on-line interfacing of a rotating bioreactor and continuous-flow/stopped-flow/continuous-flow processing. When the hydrogen peroxide formed by LO_x layer reaches the inner layer, the electronic flow between the immobilized peroxidase and the electrode surface produces a current, proportional to lactate concentration. The determination of lactate was possible with a limit of detection of 5 nmol l⁻¹ in the processing of as many as 30 samples per hour. This arrangement allows working in undiluted milk samples with a good stability and reproducibility. Horseradish peroxidase [EC 1.11.1.7] and Os-PAA were covalently immobilized on the glassy carbon electrode surface (upper cell body), lactate oxidase [EC 1.1.3.x] was immobilized on a disk that can be rotated.

How do early childhood teachers understand and support the needs of young English language Learners

In Australia, over one third of all children in Early Childhood programs speak a first language other than English. Despite considerable work into teachers' beliefs on cultural diversity, attention to aspects of second language acquisition in the Early Years has been limited within the Early Childhood field. This paper reports on a small study investigating how four early childhood educators understand theory of Second Language Acquisition (SLA) and bilingualism, and how they cater for language-minority students in their programs. The findings revealed a complex interplay between the way participants interpret and support the needs of these children, their experience in the field, and professional education. The teachers in the study reveal various perspectives on how SLA and bilingualism manifest during the early years, and how they affect the learning of children with a Language Background other than English (LBOTE). The teachers also seemed to rely on experiential and intuitive approaches in planning and teaching English Language Learners (ELLs). This study brings new perspectives to understanding the nature of teachers' beliefs and practice regarding English language learners.