Differential Scanning Calorimetry (DSC) Analyses Of Superelastic And Nonsuperelastic Nickel-Titanium Orthodontic Wires

The purpose of this study was to determine the transformation temperatures for the austenitic, martensitic, and rhombohedral (R) structure phases in representative as-received commercial nitinol (NiTi) orthodontic wire alloys, to reconcile discrepancies among recent publications. Specimens were examined by differential scanning calorimetry (DSC) over a temperature range from approximately −170° C to 100° C, with a scanning rate of 10° C per minute. Two different pathways, with the intermediate R structure either absent or present, were observed for the transformation from martensitic to austenitic NiTi, whereas the reverse transformation from austenitic to martensitic NiTi always included the R structure. The enthalpy (ΔH) for the transformation from martensite to austenite ranged from 0.3 to 35 calories per gram. The lowest ΔH value for the nonsuperelastic Nitinol wire is consistent with a largely work-hardened, stable, martensitic microstructure in this product. The DSC results indicate that the transformation processes are broadly similar in superelastic, body-temperature shape-memory, and nonsuperelastic NiTi wires. Differences in bending properties for the NiTi orthodontic wires at room temperature and 37° C are due to the relative proportions of the metallurgical phases in the microstructures

Developing Reflective Practice in Police Firearms Instruction.

This paper reports collaboration between University College Worcester and the Firearms School of West Mercia Constabulary to design, develop, implement and evaluate a national course for authorised firearms officers to become firearms instructors. The report charts its development from the time of involvement by University College Worcester and the way it has been changed to meet the needs of students. The course is based on the principles of reflective practice, encouraging firearms instructors to engage in lifelong learning as part of their continuing professional development. This central principle of reflective practice is explored in the context of the aims, delivery and outcomes of the course. Those officers who successfully complete the course are awarded the Instructors Certificate of the ACPO Firearms Committee. In addition, it is planned to award a credit accumulated transfer rated Certificate in Education to those officers who also pass the assessment set by University College Worcester. Note

Review of Australian higher education: discussion paper

The federal government\u27s review of Australia’s higher education system will examine and report on the future direction of the higher education sector, its fitness for purpose in meeting the needs of the Australian community and economy and the options for ongoing reform. This paper has been released to outline issues and invite input on the key issues identified in the review\u27s terms of reference. The paper has been structured around nine key challenges and issues for higher education in Australia over the coming decades