Poly(vinyl alcohol)-heparin biosynthetic microspheres produced by microfluidics and ultraviolet photopolymerisation

Biosynthetic microspheres have the potential to address some of the limitations in cell microencapsulation; however, the generation of biosynthetic hydrogel microspheres has not been investigated or applied to cell encapsulation. Droplet microfluidics has the potential to produce more uniform microspheres under conditions compatible with cell encapsulation. Therefore, the aim of this study was to understand the effect of process parameters on biosynthetic microsphere formation, size, and morphology with a co-flow microfluidic method. Poly(vinyl alcohol) (PVA), a synthetic hydrogel and heparin, a glycosaminoglycan were chosen as the hydrogels for this study. A capillary-based microfluidic droplet generation device was used, and by varying the flow rates of both the polymer and oil phases, the viscosity of the continuous oil phase, and the interfacial surface tension, monodisperse spheres were produced from ∼200 to 800 μm. The size and morphology were unaffected by the addition of heparin. The modulus of spheres was 397 and 335 kPa for PVA and PVA/heparin, respectively, and this was not different from the bulk gel modulus (312 and 365 for PVA and PVA/heparin, respectively). Mammalian cells encapsulated in the spheres had over 90% viability after 24 h in both PVA and PVA/heparin microspheres. After 28 days, viability was still over 90% for PVA-heparin spheres and was significantly higher than in PVA only spheres. The use of biosynthetic hydrogels with microfluidic and UV polymerisation methods offers an improved approach to long-term cell encapsulation.     

Structural and convergent validity of the homework performance questionnaire

Homework is a requirement for most school-age children, but research on the benefits and drawbacks of homework is limited by lack of psychometrically sound measurement of homework performance. This study examined the structural and convergent validity of scores from the newly developed Homework Performance Questionnaire – Teacher Scale (HPQ-T). Participants were 112 teachers of 224 students in six Illinois school districts. Common factor analysis with principal axis extraction and promax rotation was used for data analysis. Results revealed three salient factors: Parent support, student competence and homework completion. Subsequently, convergent validity of HPQ-T subscale scores with subscale scores from the Learning Behaviours Scale was examined. Findings suggest that the HPQ-T may potentially be a useful tool for improving research on homework and identifying strengths and weaknesses in student homework performance. However, modifications are recommended to optimise the utility of the scores.     

Developing a student-led school mental health strategy

Although there is increasing interest in promoting mental health and wellbeing within education, to date, the voices of young people appear to have been almost completely overlooked in the development of school-based mental health practices. This is despite increasing focus on young people’s participation; and the fact that young people may be best positioned to understand the pressures of contemporary society. This paper, co-authored by educational psychologists (EPs), school students and the school vice-principal, documents the development of a student-led mental health initiative within a high-achieving girls’ grammar school, led by students aged 12–18. Following EP input, the students devised a whole-school, student-friendly mental health strategy with the support of the EPs and senior school staff. As the project progressed, it became evident that applying even carefully selected adult mental health models to school contexts might not be appropriate; instead the students advocated for young person-friendly, innovative, contemporary and creative ways of communicating information about mental health, which avoided stigma. The students involved were well-placed to identify environmental stressors and to disseminate their strategy. The authors conclude that mental health planning in schools should encourage greater student participation, show caution over applying adult mental health models and promote greater use of technology or visual resources.     

TRANSITION TO SCHOOL: THE EXPERIENCES OF CANADIAN AND IMMIGRANT FAMILIES OF CHILDREN WITH AUTISM SPECTRUM DISORDERS

Transition to school for children with autism spectrum disorders (ASDs) places demands on children, parents, and school settings. The unique experiences of parents from diverse backgrounds have not been studied extensively. This qualitative study explored the experiences of 5 Canadian and 5 immigrant families during the transition to school for their children with ASDs. Parent perceptions of support systems during this transition and their experiences with preschool and elementary school staff were analyzed to understand their experiences. Thematic analyses of parent interviews revealed that parents perceived the quality of care during preschool as more supportive than the care received in elementary school. A variety of resources, such as familial, educational, and community support, seemed to help some Canadian and immigrant families in different ways. The transition to school experiences of parents of children with ASDs has important implications for school psychologists who facilitate and mediate parent–school partnerships and interagency collaboration.     

反季节冬春蔬菜种植农民收益的初步分析——保山市隆阳区潞江坝的实证研究

本文初步对保山市反季节蔬菜进行分析,纵向从蔬菜种子的来源、蔬菜的栽培、蔬菜的收集销售、贮藏和运输这一商品链出发,逐级分析菜农、蔬菜收集人、菜老板的收益分析,从而在整体上揭示菜农在这条商品链上的收益地位;横向同种植其他经济作物,如香烟和甘蔗的收益作对比分析。说明了西部民族山区的广大农户主要收入来源于种植业的现实,农户如何选择种植的经济作物对提高收入有直接的影响,决定农户种植收益除了市场的因素以外各级政府的行政行为则也起到一定的作用。     

A Dialogic Path to Evidence-Based Argumentive Writing

Central to argument are evidence-based claims, requiring coordination of a claim with evidence bearing on it. We advocate a dialogic approach to developing argument skills and in the work reported here examine the further scaffold of prompts that exemplify functions of evidence in relation to a claim. This scaffold was successful in accelerating the prevalence of evidence-based claims in essays of low-performing middle schoolers compared to participants in the same year-long dialog-based intervention who received no or a limited form of evidence prompts and compared to previous samples engaged in a nondialogic curriculum. An experimental group achieved a proportion of evidence-based claims above 50% by the end of the year, transferring their newly developing skill from one topic to another. The use of different types of evidence emerged in a sequence corresponding to the cognitive demands they posed. Students first used support-own evidence. They used weaken-other evidence increasingly over time, but the two evidence types inconsistent with their position (support-other and weaken-own) showed lesser and later gains. Supporting a dialogic approach, qualitative data showed that evidence use occurred most readily in dialogs; then in individual writing on the same topic; and to a more limited extent in essays on a new, unstudied topic.     

Examining Reasoning Practices and Epistemic Actions to Explore Students’ Understanding of Genetics and Evolution

Science & Education - This article focuses on students’ discursive moves and reasoning practices while engaged in a task that requires making explanatory links between sickle cell disease...