Comparison of eight published lumbar spine finite element models

Due to its ability to represent intricate systems with material nonlinearities as well as irregular loading, boundary, geometrical and material domains, the finite element (FE) method has been recognized as an important computational tool in spinal biomechanics. Current FE models generally account for a single distinct spinal geometry with one set of material properties despite inherently large inter-subject variability. The uncertainty and high variability in tissue material properties, geometry, loading and boundary conditions has cast doubt on the reliability of their predictions and comparability with reported in vitro and in vivo values. A multicenter study was undertaken to compare the results of eight well-established models of the lumbar spine that have been developed, validated and applied for many years. Models were subjected to pure and combined loading modes and their predictions were compared to in vitro and in vivo measurements for intervertebral rotations, disc pressures and facet joint forces. Under pure moment loading, the predicted L1-5 rotations of almost all models fell within the reported in vitro ranges; their median values differed on average by only 2° for flexion-extension, 1° for lateral bending and 5° for axial rotation. Predicted median facet joint forces and disc pressures were also in good agreement with previously published median in vitro values. However, the ranges of predictions were larger and exceeded the in vitro ranges, especially for facet joint forces. For all combined loading modes, except for flexion, predicted median segmental intervertebral rotations and disc pressures were in good agreement with in vivo values. The simulations yielded median facet joint forces of 0 N in flexion, 38 N in extension, 14 N in lateral bending and 60 N in axial rotation that could not be validated due to the paucity of in vivo facet joint forces. In light of high inter-subject variability, one must be cautious when generalizing predictions obtained from one deterministic model. This study demonstrates however that the predictive power increases when FE models are combined together. The median of individual numerical results can hence be used as an improved tool in order to estimate the response of the lumbar spine.

Privacy, modesty, hospitality, and the design of Muslim homes: A literature review

Traditional Islamic teachings and traditions involve guidelines that have direct applications in the domestic sphere. The principles of privacy, modesty, and hospitality are central to these guidelines; each principle has a significant effect on the design of Muslim homes, as well as on the organization of space and domestic behaviors within each home. This paper reviews literature on the privacy, modesty, and hospitality within Muslim homes. Nineteen publications from 1986 to 2013 were selected and analyzed for content related to the meaning of privacy, modesty, and hospitality in Islam and the design of Muslim homes. Despite the commonly shared guidelines for observing privacy, modesty, and hospitality within each home, Muslims living in different countries are influenced by cultural factors that operate within their country of residence. These factors help to shape the architectural styles and use of space within Muslim homes in different ways. Awareness of the multifactorial nature of the influences on the Muslim perception of home and the use of space is necessary for architects, building designers, engineers, and builders to be properly equipped to meet the needs of clients.

Are Australian homes liveable and adaptable for Muslim families? - Six case studies in Brisbane

This paper investigates how Muslims living in Brisbane live within their current Australian homes and the liveability and adaptability of these homes from the perspective of home dwellers with respect to their Islamic faiths, cultural traditions and lifestyle. A qualitative case study approach was used to gather information about Muslims’ use of domestic spaces through their lived experiences, within an Australian context. Six participants were interviewed, including: a) three Muslim families residing in one suburb of Brisbane, and; b) three international Muslim students living in three different Brisbane suburbs. These cases indicate that apart from minor difficulties, case study participants were able to perform their daily activities within their current homes through various adaptations made to ensure their respective domestic domains provided their families with privacy and a sense of security and safety. Insight gained from these cases suggest the need for more research into the homes of Muslims homes within an Australian context and the development of culturally adaptable housing as a means of meeting the diverse needs of modern Australian multicultural society.

Load applied on a bone-anchored transfemoral prosthesis: characterisation of a prosthesis : a pilot study

The objectives of this study were (A) to record the inner prosthesis loading during activities of daily living (ADL), (B) to present a set of variables comparing loading data, and (C) to provide an example of characterisation of two prostheses. The load was measured at 200 Hz using a multi-axial transducer mounted between the residuum and the knee of an individual with unilateral transfemoral amputation fitted with a bone-anchored prosthesis. The load was measured while using two different prostheses including a mechanically (PRO1) and a microprocessor controlled (PRO2) knee during six ADL. The characterisation of prosthesis was achieved using a set of variables split into four categories, including temporal characteristics, maximum loading, loading slopes and impulse. Approximately 360 gait cycles were analysed for each prosthesis. PRO1 showed a cadence improved by 19% and 7%, a maximum force on the long axis reduced by 11% and 19%, as well as an impulse reduced by 32% and 15% during descent of incline and stairs compared to PRO2, respectively. This work confirmed that the proposed apparatus and characterisation can reveal how changes of prosthetic components are translated into inner loading.

Translating biomechanics research into clinical practice

There is a large amount of research conducted each year examining every aspect of the mechanics of the human body and its interaction with medical devices and the environment; from the cellular level through to the whole body. While, as researchers, we obtain great pleasure from conducting studies and creating new knowledge we need to keep in mind that while this is a good thing it is even better if this new knowledge can lead to improvement in the quality of life for individuals suffering from biomechanical disorders. Such that while commercialisation is a good aim, not all research leads to marketable outcomes. However, it can lead to improvements in surgical techniques and clinical practice. It is important for us to identify and promote how the outcomes of research lead to improvements in quality of care, as this is perhaps the most important outcome for individual patients.

Crystal palaces: Copyright law and public architecture

This paper investigates copyright law and public architecture in the context of cultural institutions of Australia. Part 1 examines the case of the Sydney Opera House to illustrate the past position of architects in respect of copyright law. It goes onto consider the framework laid down by the Copyright Amendment (Moral Rights) Act 2000 (Cth) to resolve copyright disputes over moral rights and architecture. Part 2 considers the argument over the proposed renovations to the National Gallery of Australia between Dr Brian Kennedy and the original architect Colin Madigan. Part 3 finally deals with the allegations that Ashton Raggatt McDougall, the architects of the National Museum of Australia, plagiarised the designs of Daniel Libeskind for the Jewish Berlin Museum.