Improving Teaching and Learning in Introductory Physics

This thesis describes three studies designed to help students learn physics better and instructors teach physics more effectively in local circumstances. The first study investigated the effects of teaching approaches consisting of interactive engagement activities in two institutions. The teaching elements in the experimental classes were reading quizzes, interactive lecture demonstrations and student discussions. The control classes were taught in traditional style dominated by an instructor lecturing on concepts and problem solving examples. The cognitive improvement was measured by a standardized test and exam grades. The students in the experimental classes showed significant improvement in conceptual understanding and problem solving skills compared to the students in the control classes. While the experimental groups welcomed the modified instruction, they still held the view that the lecturer should play the dominant role of presenting the material. In the second study interviews with lecturers, teaching assistants and students revealed their perceptions of the utility of real-life materials in instruction. The students asserted that activities using real-life materials were interesting and useful. However, they still considered that elements of traditional instruction were very important in good teaching. The lack of knowledge of innovative teaching approaches may explain why the instructors were sceptical about the effectiveness of real-life materials in improving their students' understanding. To raise the instructors' awareness of issues in learning physics and to improve their knowledge of effective instruction, the third study discussed a department-based professional development course. The course incorporated interactive engagement activities and made connections to teaching and learning experiences. The course evaluation suggested that the participants became more open to new ideas and intended to implement what they had learned in the present and future academic career. The studies in this thesis have impacted on first year courses and raised the instructors' awareness of physics education issues. The emphasis of educational enterprises should be shifted from classroom changes to educating the instructors. Instead of simply modifying teaching practice, instructors should also undergo a transformation in beliefs and knowledge in pedagogy. It is only when all instructors are willing to undergo such a transformation that a significant achievement in teaching and learning will be realized

Differential gene expression between human schwannoma and control Schwann cells

The NF2 gene encodes the tumour suppressor protein merlin. The mutation of a single allele of this gene causes the autosomal dominantly inherited disease neurofibromatosis type 2 (NF2), which is characterized mainly by vestibular schwannoma carrying a second hit mutation. Complete lack of merlin is also found in spontaneous schwannomas and meningiomas. As the events leading to schwannoma development are largely unknown we investigated the differences in gene expression between schwannoma cells from NF2 patients and normal human primary Schwann cells by cDNA array analysis. We identified 41 genes whose expression levels differed by more than factor 2. Most of these clones were corroborated by real-time reverse transcription polymerase chain reaction analysis. By this method a total of seven genes with increased and seven genes with decreased mRNA levels in schwannoma compared with normal Schwann cells could be identified. Regulated clones, some of which not been described in Schwann cells earlier, included matrix metalloproteinase's, growth factors, growth factor receptors and tyrosine kinases