Optofluidic characterization of marine algae using a microflow cytometer

The effects of global warming, pollution in river effluents, and changing ocean currents can be studied by characterizing variations in phytoplankton populations. We demonstrate the design and fabrication of a Microflow Cytometer for characterization of phytoplankton. Guided by chevron-shaped grooves on the top and bottom of a microfluidic channel, two symmetric sheath streams wrap around a central sample stream and hydrodynamically focus it in the center of the channel. The lasers are carefully chosen to provide excitation light close to the maximum absorbance wavelengths for the intrinsic fluorophores chlorophyll and phycoerythrin, and the excitation light is coupled to the flow cytometer through the use of an optical fiber. Fluorescence and light scatter are collected using two multimode optical fibers placed at 90-degree angles with respect to the excitation fiber. Light emerging from these collection fibers is directed through optical bandpass filters into photomultiplier tubes. The cytometer measured the optical and side scatter properties of Karenia b., Synechococcus sp., Pseudo-Nitzchia, and Alexandrium. The effect of the sheath-to-sample flow-rate ratio on the light scatter and fluorescence of these marine microorganisms was investigated. Reducing the sample flow rate from 200 μL/min to 10 μL/min produced a more tightly focused sample stream and less heterogeneous signals.     

The impact of preprimary school on primary school achievement in Bangladesh

Evidence was collected regarding changes over 3 years in the quality of a preprimary program in rural Bangladesh and differences in school achievement of children who did and did not attend. The quality of 30 preprimary schools was evaluated using the ECERS-R (Early Childhood Environment Rating Scale - Revised) and ECERS-E (- Extension). Results indicated that the quality improved overall from 3.50 in 2006 to 5.24 in 2008. Samples of 180 graduates of these schools were annually followed into first and second grades and tested for five competencies: speaking, writing, reading, oral mathematics and written mathematics. Their achievement scores were compared with students in their classrooms and students in neighboring schools who did not have the opportunity to attend preprimary schools. First graders in 2008 performed significantly better than comparisons in all competencies, and better than earlier graduates. Second graders performed significantly better than comparisons on all but Reading. Qualities of the math preprimary program correlated with math achievement in Grade 1 only. Consequently the quality of the preprimary program improved over time along with higher achievement for its graduates. The findings support efforts to expand high-quality programs in developing countries to help children succeed in the early primary grades.     

Schooling citizens: policy in practice in South Africa

The notion of ‘student citizen’ is implicit in a range of national and provincial policy documents in South Africa, with citizenship promoted as both an expected outcome of schooling and an encouraged practice within schools. This paper provides an account of how policy on student citizenship was translated differently into practice in four secondary schools in Cape Town, each with a different former racial categorisation under apartheid. It argues that student engagement with citizenship varied considerably between the schools and in many cases was significantly different from the policy framework. Influencing factors included staff–student relations, socio‐historical contexts and how diversity was played out in the schools.     

Dark matter: the ‘gravitational pull’ of maternalist discourses on politicians’ decision making for early childhood policy in Australia

The article reports on a study investigating influences on Australian politicians’ decision making for early childhood education and care (ECEC) policy. The astronomical concept of dark matter is utilised as a metaphor for considering normalising, and therefore frequently difficult to detect and disrupt, influences implicated in politicians’ decision making for ECEC policy. The concept of dark matter connects with and extends Foucauldian conceptualisations of knowledge, power and discourse. The paper argues that maternalist discourses continue to shape the policy landscape for ECEC, though these are largely unacknowledged.     

Our Practice, Their Readiness: Teacher Educators Collaborate to Explore and Improve Preservice Teacher Readiness for Science and Math Instruction

Since many preservice teachers (PTs) display anxiety over teaching math and science, four PT educators collaborated to better understand the PTs’ background experiences and attitudes toward those subjects. The research project provided two avenues for professional learning: the data collected from the PTs and the opportunity for collaborative action research. The mixed method study focused on: the relationship between gender and undergraduate major (science versus non-science) with respect to previous and current engagement in science and math, understanding the processes of inquiry, and learning outside the classroom. A field trip to a science center provided the setting for the data collection. From a sample of 132 PTs, a multivariate analysis showed that the science major of PTs explained most of the gender differences with respect to the PTs’ attitudes toward science and mathematics. The process of inquiry is generally poorly interpreted by PTs, and non-science majors prefer a more social approach in their learning to teach science and math. The four educators/collaborators reflect on the impacts of the research on their individual practices, for example, the need to: include place-based learning, attend to the different learning strategies taken by non-science majors, emphasize social and environmental contexts for learning science and math, be more explicit regarding the processes of science inquiry, and provide out-of-classroom experiences for PTs. They conclude that the collaboration, though difficult at times, provided powerful opportunities for examining individual praxis.     

Transition to the School as Workplace: Challenges of second career teachers

This article details the transition of second career teachers to the workplace called ‘school’. Post‐baccalaureate students at a mid‐size comprehensive state university completed surveys pre‐ and post‐student teaching. Participants responded to the personal and professional challenges in changing careers. Issues faced by the non‐traditional students emerged. An increasing number of adults are changing careers and entering teacher certification programs. The study was conducted to discover the special challenges graduate teacher certification students encountered when leaving a career field and becoming novice teachers. Forty graduate students in the study completed an extensive certification program of courses related to the art and science of teaching. Open‐ended surveys were used for the students to reflect on personal and professional expectations prior to and following the student teaching semester. Teacher educators who address the needs of second career teachers, such as increasing field experiences, providing classroom management and time management strategies, may lead second career teachers to use the unique competencies they bring to the teaching–learning setting.     

The meaning of play: A cross‐cultural study of American and Japanese teachers’ perspectives on play

Abstract

Early childhood teachers’ understandings of play were examined in a qualitative comparative study of 41 Japanese and 41 American participants. Qualitative analysis of the data yielded five themes: the power of living, the opportunity to learn and to develop, fun activities, child's work, and the opportunity to explore nature. Two themes emerged in regard to the meaning of play for adults: enjoyable and voluntary activities and child's play. Finally, we identified two themes regarding playfulness: state of heart and fun feelings. Teachers in both nations used rhetoric that is congruent with the current Zeitgeist of developmentally appropriate early education. One theme that differentiated the groups was the notion that play is children's work. While several Americans mentioned this slogan, this was not the case for the Japanese participants. In contrast, the theme of play as the power of living was more representative of Japanese teachers’ understandings of play, and this reflects the philosophy set forth by the Japanese Ministry of Education, Culture, Sports, Science, and Technology.     

Changing schools: still trying after all these years

The present study focuses on the way novice teachers, who are part of a one-year postgraduate diploma in post-primary teaching, have opted to negotiate their status as school teachers. In particular, it asks why novice teachers prefer to hide as they scramble to learn how to teach. On the basis of three separate interviews spaced out though the teaching year 2009 (January, March, May), a team of university-based tutors probed for student reactions to competence-based issues. Adopting a sociocultural perspective, this study drew upon roughly 10% of the pre-service student cohort (n?=?17), each in a different placement location. The study looked, in particular, at their negotiating power, particularly the effect of school supports for their reality as learners. Findings suggest that without quality mentoring support, our pre-service teachers prefer to become ‘invisible’ as learners. Three pre-professional stances are identified: fragile, robust and competitive. The key finding is that none of these pre-professional stances mitigate pre-service students’ lack of negotiating power. On the other hand, informal school-based supports can help students considerably.