Exploration of Year 10 students' conceptual change during instruction

This article reports on a classroom-based case study of a group of six Year 10 students, within a class of 23 students. The study implemented constructivist-informed teaching and learning approaches within a classroom setting in the topic of optics and documented any changes in the conceptual understanding students had about seven central concepts of geometrical optics over a teaching sequence lasting nine weeks.

Secondary students` perceptions of a constructivist-informed teaching and learning environment for geometric optics

This article describes an exploration of a class of secondary school students perceptions of a constructivist informed teaching and learning environment for geometric optics. The students perceived the environment as one where they could freely express their ideas and be involved in activities. What was also apparent in this exploration was the students' preference for a classroom that involved small group discussions to whole class discussions that reflected a need for time to think about issues. They also have a preference for relevant, practical work that tests their ideas and a preference to have fewer notes that they construct themselves rather than notes dictated by the teacher.

NT: Refereed article. Includes bibliographical references.

Agricultural intensification and loss of matrix habitat over 23 years in the West Wimmera, south-eastern Australia

The global trend toward more intensive forms of agriculture is changing the nature of matrix habitat in agricultural areas. Removal of components of matrix habitat can affect native biota at the paddock and the landscape scale, particularly where intensification occurs over large areas. We identify the loss of paddock trees due to the proliferation of centre pivot irrigation in dryland farming areas as a potentially serious threat to the remnant biota of these areas. We used a region of south-eastern Australia as a case study to quantify land use change from grazing and dryland cropping to centre pivot irrigation over a 23-year period. We also estimated rates of paddock tree loss in 5 representative landscapes within the region over the same period. The total area affected by centre pivots increased from 0 ha in 1980 to nearly 9000 ha by 2005. Pivots were more likely to be established in areas which had originally been plains savannah and woodlands containing buloke (Allocasuarina luehmannii), a food source for an endangered bird. On average, 42% of paddock buloke trees present in 1982 were lost by 2005. In the two landscapes containing several centre pivots, the loss was 54% and 70%. This accelerated loss of important components of matrix habitat is likely to result in species declines and local extinctions. We recommend that measures to alleviate the likely negative impacts of matrix habitat loss on native biota be considered as part of regional planning strategies.

Recovery following laparoscopic cholecystectomy in either a 23 hour or an 8 hour facility

Research confirms that laparoscopic cholecystectomy (LC) results in shorter lengths of hospital stay and earlier return to usual activity than the traditional cholecystectomy procedure. Research in this area, however, focuses more on the medical aspects of patient recovery, but very few studies have evaluated how these patients manage their recovery at home or what types of problems they encounter. A total of 28 LC patients were randomly assigned to two groups: (1) 23 h stay (overnight) in a general surgical ward or (2) day procedure unit (DPU) stay. Data was collected by a self-administered Postoperative Symptoms Diary and telephone interview. Results showed no significant difference between the two groups of patients recovery symptoms scores. Problems with mobility, pain and elimination recorded the highest mean scores for both groups of patients. Overnight patients also experienced problems with tiredness and eating. All DPU patients were able to manage their postoperative symptoms, compared to only 44% of patients who had stayed in overnight. Carer assistance was needed with regard to activities of daily living, child care and reassurance. Results showed that with careful selection of patients, LC cases performed as day procedures did not impact at all on the patients' recovery trajectory.

Skew arcs and Wagner's [23, 14, 5] code

In 1966, Wagner used computational search methods to construct a  [23,14,5] code. This code has been examined with much interest since that time, in hopes of finding a geometric construction and possible code extensions. In this article, we give a simple geometric construction for Wagner's code and consider extensions of this construction.