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Three-dimensional (3D) printing is increasingly used to produce orthopaedic components for hip arthroplasty, such as acetabular cups, which show complex lattice porous structures and shapes. However, limitations on the quality of the final implants are present; thus, investigations are needed to ensure adequate quality and patients safety. X-ray microcomputed tomography (micro-CT) has been recognised to be the most suitable method to evaluate the complexity of 3D-printed parts. The purpose of this study was to assess the reliability of a micro-CT analysis method comparing it with reference systems, such as coordinate measuring machine and electron microscopy.

3D-printed acetabular components for hip arthroplasty (n = 2) were investigated. Dimensions related to the dense and porous regions of the samples were measured. The micro-CT scanning parameters (voltage – kV, current – µA) were optimised selecting six combinations of beam voltage and current.

Micro-CT showed good correlation and agreement with both coordinate measuring machine and scanning electron microscopy when optimal scanning parameters were selected (130 kV – 100 µA to 180 kV – 80 µA). Mean discrepancies of 50 µm (± 300) and 20 µm (± 60) were found between the techniques for dense and porous dimensions. Investigation method such as micro-CT imaging may help to better understand the impact of 3D printing manufacturing technology on the properties of orthopaedic implants.

The optimisation of the scanning parameters and the validation of this method with reference techniques may guide further analysis of similar orthopaedic components.

This chapter provides a brief overview of community sanctions in Australia and examines the extent to which McNeill’s analysis in Pervasive Punishment (2019) is applicable in the Australian context. Two key issues in the Australian context are, firstly, state and territory-level variations within a federal political structure, and secondly, disproportionate Indigenous imprisonment and community sanction rates and the generally destructive impact of the criminal legal system on Indigenous communities and peoples. The chapter argues that developing a better agonistic politics around community sanctions requires descending from the broad level of historical and sociological analysis to examine state and territory-level variations in judicial and correctional structures, histories and cultures. Further, that Australian community sanctions cannot be understood without a primary focus on the differences between Indigenous and non-Indigenous rates, experiences and meaning. The key to addressing the destructive impact of criminal legal processes and practices on Indigenous peoples lies in developing Indigenous governance, empowerment, self-determination, sovereignty and nation-building. Two recent developments promoting Indigenous governance are examined: the Uluru Statement from the Heart and Justice Reinvestment projects initiated by First Nations communities, highlighting the importance of activism, contest and struggle by community organisations.

THE announcement that Mr. James Wilkie, M.A., will be President of the Library Association for 1951 is gratifying, He has been for some years the honoured Secretary of the Carnegie Trust and before that was the officer at the Ministry of Education most nearly concerned with the public library. For many years now he has been a familiar figure at library conferences, and his geniality, Strong sense of humour and excellent speaking, have won him the esteem of librarians and others concerned with libraries. He almost invariably attends the meetings of the National Central Library. It is, therefore, appropriate that he should preside over the Library Association, which owes so much to him and the Trust he serves and in many activities represents. We wish him a pleasant year of office and can surely promise him the loyalty of librarians.