Formation of embryoid bodies using dielectrophoresis

Embryoid body (EB) formation forms an important step in embryonic stem cell differentiation invivo. In murine embryonic stem cell (mESC) cultures EB formation is inhibited by the inclusion of leukaemic inhibitory factor (LIF) in the medium. Assembly of mESCs into aggregates by positive dielectrophoresis (DEP) in high field regions between interdigitated oppositely castellated electrodes was found to initiate EB formation. Embryoid body formation in aggregates formed with DEP occurred at a more rapid rate-in fact faster compared to conventional methods-in medium without LIF. However, EB formation also occurred in medium in which LIF was present when the cells were aggregated with DEP. The optimum characteristic size for the electrodes for EB formation with DEP was found to be 75-100 microns; aggregates smaller than this tended to merge, whilst aggregates larger than this tended to split to form multiple EBs. Experiments with ESCs in which green fluorescent protein (GFP) production was targeted to the mesodermal gene brachyury indicated that differentiation within embryoid bodies of this size may preferentially occur along the mesoderm lineage. As hematopoietic lineages during normal development derive from mesoderm, the finding points to a possible application of DEP formed EBs in the production of blood-based products from ESCs.     

The problematic relationship between child development theory and teacher preparation

Abstract

This article addresses questions raised in the past decade regarding the role of child development knowledge for teaching and teacher preparation. Missing from the dialogue on this issue have been the voices of the students enrolled in teacher preparation programs. Accordingly, 77 preservice teachers were surveyed at the conclusion of a child development theory course. The results were examined for themes regarding how preservice teachers come to understand the changing nature of child development, the strengths and limitations of generalized theories of development, and the applicability of child development theory to their future practice.     

Automated Scoring of Constructed‐Response Science Items: Prospects and Obstacles

Content‐based automated scoring has been applied in a variety of science domains. However, many prior applications involved simplified scoring rubrics without considering rubrics representing multiple levels of understanding. This study tested a concept‐based scoring tool for content‐based scoring, c‐rater?, for four science items with rubrics aiming to differentiate among multiple levels of understanding. The items showed moderate to good agreement with human scores. The findings suggest that automated scoring has the potential to score constructed‐response items with complex scoring rubrics, but in its current design cannot replace human raters. This article discusses sources of disagreement and factors that could potentially improve the accuracy of concept‐based automated scoring.     

Play — Use — Generalize! Three-stage activities for developing math readiness

Children can be encouraged to demonstrate academic learning that they have mastered. Demonstrating academic learning to adults can be similar to auditioning for a drama or an artistic recital. Teachers and professional caregivers are accustomed to such auditions. Typically, it is the parents who initiate the audition: “My child can count to 10. Bonnie, count to 10 for this person.” Sometimes the auditioning child will ignore the parent: “Bonnie, count to 10 for this nice man.” Bonnie continues to disregard her parent. “Bonnie, count to 10. You know how to do it. One, two, three, ... What comes after three?” Bonnie still does not respond. “Honey, say your numbers. One, two, thr... What comes after two?”     

We Are All Teachers: A Collaborative Approach to Digital Collection Development

ABSTRACT

In libraries and archives, efforts to document underrepresented communities and diversify collections can be fraught with political tension. We explore an interdepartmental collaboration to create and preserve a digital collection documenting the Urban Native Relocation Program of the mid- to late-twentieth century in Grand Rapids, Michigan. Involving the Grand Valley State University Libraries, the Kutsche Office of Local History, and the university's Native American Advisory Board, the project serves as a model not just for collaborative collection development but also for community engagement and outreach. We find that process is as important as product in developing collaborative digital collections.     

Principal Leadership for Technology-enhanced Learning in Science

Reforms such as technology-enhanced instruction require principal leadership. Yet, many principals report that they need help to guide implementation of science and technology reforms. We identify strategies for helping principals provide this leadership. A two-phase design is employed. In the first phase we elicit principals’ varied ideas about the Technology-enhanced Learning in Science (TELS) curriculum materials being implemented by teachers in their schools, and in the second phase we engage principals in a leadership workshop designed based on the ideas they generated. Analysis uses an emergent coding scheme to categorize principals’ ideas, and a knowledge integration framework to capture the development of these ideas. The analysis suggests that principals frame their thinking about the implementation of TELS in terms of: principal leadership, curriculum, educational policy, teacher learning, student outcomes and financial resources. They seek to improve their own knowledge to support this reform. The principals organize their ideas around individual school goals and current political issues. Principals prefer professional development activities that engage them in reviewing curricula and student work with other principals. Based on the analysis, this study offers guidelines for creating learning opportunities that enhance principals’ leadership abilities in technology and science reform.     

Effects of implementing flipped classroom elements and dynamic in‐class discussion on student performance

In a Food Processing–Unit Operations course, students learn the basic equipment that comprises unit operations and techniques commonly used in the food industry to prepare, process, and preserve a variety of food products. Due to the complexity of these operations, students frequently struggle with applying food processing principles to predict how unit operations influence the physical, biochemical, sensory, and nutritional properties of foods. This study is designed to evaluate how pre‐class readings and in‐class group activities improve the students’ learning in a Food Processing course. The survey after the exams shows that 48 and 60% of students agree that reading assignments and in‐class group activities help them understand the course material better, respectively. The mean value of exam scores shows that the students in the intervention section (Spring 2018) had significantly higher scores (88.4%) than that of the two previous sections without intervention (77.6%, Spring 2016 and 82.8%, Spring 2017) (P < .05). It is concluded that using a flipped class element like providing reading assignments and quizzes before the lecture can be an effective preparation technique for students as well as providing the instructors with critical insight into the students’ level of understanding before the lecture. This allows the instructor to focus time spent in class on areas in which students struggle the most.     

Communicative Foreign Language Teaching and how it Reflects on the Training of Modern Foreign Language Teachers

If acquiring a foreign language is a highly individual process—part cognitive part affective, part information based part discovery based—the methodology of creating teaching/learning situations must take (next to linguistic issues) the individual into account: his learning style, his needs, interests, etc.

The article has two distinct emphases: (I) a cognitive, applied linguistics emphasis and (II) an affective, learner‐centred emphasis. By way of conclusion the implications of (I) and (II) for teacher training are involved.     

PROBLEM FINDING: DISCOVERING AND FORMULATING PROBLEMS

Research and theory on problem finding are scarce. This can be ascribed to difficulties in the operationalisation of the concept and to neglect of the importance of this essential link in the problem solving cycle. A similar lacuna, however, is not found in early research in the field of problem solving. In problem solving four components can be distinguished: cognitive (sensitivity to problems and formulating the problem), motivational (effectance motivation and curiosity), emotional (wonder and surprise) and, finally, personality components (tolerance for ambiguity, stimulus reduction and self‐confidence). Selective encoding, combining and comparing can be regarded as essential elements of the cognitive component. With respect to the developmental aspects of problem finding, emphasis is laid on the importance of competence motivation and the quality of attachment as determinants. The educational implications are unequivocal: problem solving and problem finding must have equal positions in curricula. For the time being this means that education will have to pay more attention to problem finding.     

Disruption of chickens’ color aversions when training and test mediums are different

Learning & Behavior - In the present experiments, the conditions under which chickens would avoid colored and flavored substances that they had associated with toxicosis were examined. It was...