An open source heterogeneous 3D printed mouse phantom utilising a novel bone representative thermoplastic

The lack of rigorous quality standards in pre-clinical radiation dosimetry has renewed interest in the development of anthropomorphic phantoms. Using 3D printing customisable phantoms can be created to assess all parts of pre-clinical radiation research: planning, image guidance and treatment delivery. We present the full methodology, including material development and printing designs, for the production of a high spatial resolution, anatomically realistic heterogeneous small animal phantom. A methodology for creating and validating tissue equivalent materials is presented. The technique is demonstrated through the development of a bone-equivalent material. This material is used together with a soft-tissue mimicking ABS plastic filament to reproduce the corresponding structure geometries captured from a CT scan of a nude mouse. Air gaps are used to represent the lungs. Phantom validation was performed through comparison of the geometry and x-ray attenuation of CT images of the phantom and animal images. A 6.6% difference in the attenuation of the bone-equivalent material compared to the reference standard in softer beams (0.5 mm Cu HVL) rapidly decreases as the beam is hardened. CT imaging shows accurate (sub-millimetre) reproduction of the skeleton (Distance-To-Agreement 0.5 mm ± 0.4 mm) and body surface (0.7 mm ± 0.5 mm). Histograms of the voxel intensity profile of the phantom demonstrate suitable similarity to those of both the original mouse image and that of a different animal. We present an approach for the efficient production of an anthropomorphic phantom suitable for the quality assurance of pre-clinical radiotherapy. Our design and full methodology are provided as open source to encourage the pre-clinical radiobiology community to adopt a common QA standard

‘Blurred lines’

The recent review of the national curriculum, which places Physical Education as a compulsory subject at key stages 1–4, indicates a government commitment to the subject. However, given the contested history of Physical Education’s priorities and practices, such commitment should, perhaps, be handled with care. The main strength of Physical Education lies in its ability to develop the child holistically, through a focus on the promotion of physical literacy, but more recently the emphasis has been on its ability to support academic achievement. This suggests a dualistic view of Physical Education, whereby the mind and body are separate and physicality is viewed as a subservient function to cognition. It is argued, however, that these aspects cannot be separated, as it is the holistic development rooted in monism that enables the individual to flourish both physically and intellectually. In January 2011, the Department for Education launched a review of the national curriculum, with a ‘greater emphasis on competition’. This totally ignores the notion that competition does not suit everyone and may be catastrophic for some pupils’ self-esteem, having implications for physical activity levels. This paper concludes that a number of aspects require further consideration if the true value of Physical Education is to be realised. The pedagogical implications of a curriculum underpinned by physical literacy must be debated and a consolidated approach agreed