Exploring the relationship between task, teacher actions, and student learning

We are examining actions that teachers take to convert tasks into learning opportunities. In this paper, we contrast ways that three teachers convert the same task into lessons, and the way that their lessons reflect their intent. We found that the teachers did what they intended to do, that this was connected to their appreciation of the mathematics involved, and directly influenced the learning opportunities of the students. To the extent that the potential of the task was reduced, this seemed due to the lack of mathematical confidence in the case of two of the teachers

Single camera 3D planar Doppler velocity measurements using imaging fibre bundles

Two frequency planar Doppler Velocimetry (2ν-PDV) is a modification of the Planar Doppler Velocimetry (PDV) method that allows velocity measurements to be made, quickly and non intrusively, across a plane defined by a laser light sheet. In 2ν-PDV the flow is illuminated sequentially with two optical frequencies, separated by about 700MHz. A single CCD viewing through an iodine absorption cell is used to capture images under each illumination. The two images are used to find the normalised transmission through the cell, and the velocity information is encoded as a variation in the transmission Use of a single camera ensures registration of the reference and signal images and removes issues associated with the polarization sensitivity of the beam splitter, which are major problems in the conventional approach. A 2ν-PDV system has been constructed using a continuous-wave Argon ion laser combined with multiple imaging fibre bundles, to port multiple views of the measurement plane to a CCD camera, allowing the measurement of three velocity components.EPSR

Single camera 3D planar Doppler velocity measurements, using two frequency planar Doppler velocimetry (2v-PDV) and imaging fibre bundles

A modified Planar Doppler Velocimetry (PDV) technique, two frequency PDV (2v-PDV), is described that allows measurements of the velocity field over a plane defined by a laser light sheet using sequential illumination of the flow with two closely separated (&IGHz) frequencies of laser light. This allows a common-path imaging head to be used containing a single CCD camera instead of the usual camera pair. The problem of image misalignment is now avoided and the polarisation sensitivity of the beam splitter used in two camera imaging heads is also removed. Cost efficiency is improved by the simplification of the system. This paper describes the development of a 2v-PDV system using a continuous wave argon ion laser capable of making time-averaged velocity measurements. Initially a single velocity component system was constructed using acousto-optic modulators to produce the two illumination frequencies required. The system was then expanded to make 3D velocity measurements using a single CCD camera and multiple coherent imaging fibre bundles. Measurements were made on the rotating disc, in order to assess error level in the measurements, and on a seeded axisymmetric air jet. A method of improving the sensitivity of the 2v-PDV system is demonstrated by using both the rising and falling slopes of the iodine absorption line. Reductions in the error levels of velocity measurements of approximately 40% can be achieved using this increased sensitivity method

Complete eigenstates of identical qubits arranged in regular polygons

We calculate the energy eigenvalues and eigenstates corresponding to coherent single and multiple excitations of an array of N identical qubits or two-level atoms (TLA's) arranged on the vertices of a regular polygon. We assume only that the coupling occurs via an exchange interaction which depends on the separation between the qubits. We include the interactions between all pairs of qubits, and our results are valid for arbitrary distances relative to the radiation wavelength. To illustrate the usefulness of these states, we plot the distance dependence of the decay rates of the n=2 (biexciton) eigenstates of an array of 4 qubits, and tabulate the biexciton eigenvalues and eigenstates, and absorption frequencies, line widths, and relative intensities for polygons consisting of N=2,...,9 qubits in the long-wavelength limit.Comment: Added a figure showing how these results can be used to compute deviations from "equal collective decoherence" approximation

e-Mental health for mood and anxiety disorders in general practice

Familiarises general practitioners (GPs) with the range of online programs in Australia that have demonstrated efficacy and are currently available for use by patients with mental health problems. Background Australia is a world leader in the development of internetdelivered programs for the prevention and management of mood and anxiety disorders. Despite a strong evidence base of time- and cost-effectiveness, as well as clinical efficacy, the uptake of these programs in general practice remains low. Objective To familiarise general practitioners (GPs) with the range of online programs in Australia that have demonstrated efficacy and are currently available for use by patients with mental health problems. Discussion E-mental health programs provide an efficacious and accessible form of mental healthcare and have the potential to fill the gap for those for whom such care is inaccessible, unaffordable or unacceptable. Clinicians can also use it in a stepped-care manner to augment existing healthcare services. There are a number of online resources currently available to Australians who have mood or anxiety disorders. These resources have strong evidence to support their effectiveness. Online portals facilitate access to these programs. Recently the Australian Federal Government has funded an education program (eMHPrac) for GPs and mental health professionals, to outline what is available, indicate situations where recommending such resources is appropriate, and suggest ways in which they can be incorporated into general practice

The Rhetoric of Refugees: Literacy, Narrative and Identity for Somali Women

This dissertation is a project in the recovery of the subjugated voices of Somali women who are living in the United States as a result of forced migration. Using a transactional, reflective, and activist methodology, I interviewed Somali women in an effort to recognize how multiples discourses of power impact assimilation and identity formation in their lives. I hope to influence how members of dominant cultures, particularly western cultures, research and write about refugees. This study considers the aspects of being Somali, a refugee, and a woman in the United States. As a contribution to academic discourse, I hope the way I approach and present my research will offer a new appreciation for refugees and their contributions to our communities