Separable spatiotemporal priors for convex reconstruction of time-varying 3D point clouds

Reconstructing 3D motion data is highly under-constrained due to several common sources of data loss during measurement, such as projection, occlusion, or miscorrespondence. We present a statistical model of 3D motion data, based on the Kronecker structure of the spatiotemporal covariance of natural motion, as a prior on 3D motion. This prior is expressed as a matrix normal distribution, composed of separable and compact row and column covariances. We relate the marginals of the distribution to the shape, trajectory, and shape-trajectory models of prior art. When the marginal shape distribution is not available from training data, we show how placing a hierarchical prior over shapes results in a convex MAP solution in terms of the trace-norm. The matrix normal distribution, fit to a single sequence, outperforms state-of-the-art methods at reconstructing 3D motion data in the presence of significant data loss, while providing covariance estimates of the imputed points.

Biceps femoris architecture and strength in athletes with a prior ACL reconstruction

Purpose To determine if limbs with a history of anterior cruciate ligament (ACL) injury reconstructed from the semitendinosus (ST) display different biceps femoris long head (BFlh) architecture and eccentric strength, assessed during the Nordic hamstring exercise, compared to the contralateral uninjured limb. Methods The architectural characteristics of the BFlh were assessed at rest and at 25% of a maximal voluntary isometric contraction (MVIC) in the control (n=52) and previous ACL injury group (n=15) using two-dimensional ultrasonography. Eccentric knee-flexor strength was assessed during the Nordic hamstring exercise. Results Fascicle length was shorter (p=0.001; d range: 0.90 to 1.31) and pennation angle (p range: 0.001 to 0.006: d range: 0.87 to 0.93) was greater in the BFlh of the ACL injured limb when compared to the contralateral uninjured limb at rest and during 25% of MVIC. Eccentric strength was significantly lower in the ACL injured limb than the contralateral uninjured limb (-13.7%; -42.9N; 95% CI = -78.7 to -7.2; p=0.021; d=0.51). Fascicle length, MVIC and eccentric strength were not different between the left and right limb in the control group. Conclusions Limbs with a history of ACL injury reconstructed from the ST have shorter fascicles and greater pennation angles in the BFlh compared to the contralateral uninjured side. Eccentric strength during the Nordic hamstring exercise of the ACL injured limb is significantly lower than the contralateral side. These findings have implications for ACL rehabilitation and hamstring injury prevention practices which should consider altered architectural characteristics.

Pain location, distribution and intensity after cardiac surgery

Research Review on: Mueller X, Tinguely F, Tevaearai H, Revelly J, Chiolero R & Von Segess L. Pain location, distribution and intensity after cardiac surgery. Chest 2000; 118(2):391.396.

A qualitative study of the spouse's experience following coronary artery bypass surgery: Implications for Nursing Practice

Findings from numerous quantitative studies suggest that spouses of patients undergoing Coronary Artery Bypass (CAB) surgery experience both physical and emotional stress before and after their partner's surgery. Such studies have contributed to our understanding of the spouses' experiences, however they have largely failed to capture the qualitative experience of what it is like to be a spouse of a partner who has undergone CAB surgery. The objective of this study was to describe the experience of spouses of patients who had recently undergone CAB surgery. This study was guided by Husserl's phenomenological approach to qualitative research. In accordance with the nature of phenomenological research the number of participants necessarily needs to be small because phenomenology values the unique experience of individuals. Therefore this study gathered data from four participants utilising open ended indepth interviews. The method of analysis was adapted from Amedeo Giorgi's five step empirical phenomenological process which brackets preconceived notions, reducing participants' accounts to the essential essence or meanings. Numerous themes common to each of the spouses emerged. These included: seeking information; the necessity for rapid decision making; playing guardian; a desire to debrief with their partner and lastly, uncertainty of their future role. This study has attempted to understand the phenomena of the spouse's experience and in doing so, believe that we now have a better understanding and insight into the needs of spouses of CAB surgery patients. This has added another dimension to our existing body of knowledge and further facilitates holistic patient care.

Study of reproducibility of human arterial plaque reconstruction and its effects on stress analysis based on multispectral in vivo magnetic resonance imaging

Purpose: To quantify the uncertainties of carotid plaque morphology reconstruction based on patient-specific multispectral in vivo magnetic resonance imaging (MRI) and their impacts on the plaque stress analysis. Materials and Methods: In this study, three independent investigators were invited to reconstruct the carotid bifurcation with plaque based on MR images from two subjects to study the geometry reconstruction reproducibility. Finite element stress analyses were performed on the carotid bifurcations, as well as the models with artificially modified plaque geometries to mimic the image segmentation uncertainties, to study the impacts of the uncertainties to the stress prediction. Results: Plaque reconstruction reproducibility was generally high in the study. The uncertainties among interobservers are around one or the subpixel level. It also shows that the predicted stress is relatively less sensitive to the arterial wall segmentation uncertainties, and more affected by the accuracy of lipid region definition. For a model with lipid core region artificially increased by adding one pixel on the lipid region boundary, it will significantly increase the maximum Von Mises Stress in fibrous cap (>100%) compared with the baseline model for all subjects. Conclusion: The current in vivo MRI in the carotid plaque could provide useful and reliable information for plaque morphology. The accuracy of stress analysis based on plaque geometry is subject to MRI quality. The improved resolution/quality in plaque imaging with newly developed MRI protocols would generate more realistic stress predictions.

Closed-form solutions for low-rank non-rigid reconstruction

Recovering the motion of a non-rigid body from a set of monocular images permits the analysis of dynamic scenes in uncontrolled environments. However, the extension of factorisation algorithms for rigid structure from motion to the low-rank non-rigid case has proved challenging. This stems from the comparatively hard problem of finding a linear “corrective transform” which recovers the projection and structure matrices from an ambiguous factorisation. We elucidate that this greater difficulty is due to the need to find multiple solutions to a non-trivial problem, casting a number of previous approaches as alleviating this issue by either a) introducing constraints on the basis, making the problems nonidentical, or b) incorporating heuristics to encourage a diverse set of solutions, making the problems inter-dependent. While it has previously been recognised that finding a single solution to this problem is sufficient to estimate cameras, we show that it is possible to bootstrap this partial solution to find the complete transform in closed-form. However, we acknowledge that our method minimises an algebraic error and is thus inherently sensitive to deviation from the low-rank model. We compare our closed-form solution for non-rigid structure with known cameras to the closed-form solution of Dai et al. [1], which we find to produce only coplanar reconstructions. We therefore make the recommendation that 3D reconstruction error always be measured relative to a trivial reconstruction such as a planar one.

Improving the outcomes of foot and ankle surgery. Professional impact of the Australasian College of Podiatric Surgeons' audit tool

Background Surgery is an example of expanded practice scope that enhances podiatry and incorporates inter-professional collaboration. By 2050 demand for foot and ankle procedures is predicted to rise nationally by 61.9%. Performance management of this increase motivated the development of an online audit tool. Developed in collaboration with the Australasian College of Podiatric Surgeons (ACPS), the ACPS audit tool provides real-time data capture and reporting. It is the first audit tool designed in Australia to support and improve the outcomes of foot and ankle surgery. Methods Audit activity in general, orthopaedic, plastic and podiatric surgery was examined using a case study design. Audit participation enablers and barriers were explored. Case study results guided a Delphi survey of international experts experienced or associated with foot and ankle surgery. Delphi survey-derived consensus informed modification of a generic data set from the Royal Australasian College of Surgeons (RACS). Based on the Delphi survey findings the ACPS online audit tool was developed and piloted. Reliability and validity of data entry and usability of this new tool was then assessed with an online survey. Results The case study found surgeon attitudes and behaviours positively impacted audit participation, and also indicated that audit data should be: (1) available in real time, (2) identify practice change, (3) applicable for safety and quality management, and; (4) useful for peer review discussion. The Delphi process established consensus on audit variables to be captured, including the modified RACS generic data set. 382 cases of foot and ankle surgery were captured across 3 months using the new tool. Data entry was found to be valid and reliable. Real-time outcome reporting and practice change identification impacted positively on safety and quality management and assisted peer review discussion. An online survey showed high levels of usability. Conclusions Surgeon contribution to audit tool development resulted in 100% audit participation. The data from the ACPS audit tool supported the ACPS submission to the Medical Services Advisory Committee to list podiatric surgery under Medicare, an outcome noted by the Federal Minister of Health.

Diabetic charcot neuroarthropathy of the knee: Conservative treatment options as alternatives to surgery

In contrast to the well-known Charcot neuroarthropathy (CN) of the foot, CN of the knee is hardly recognized. In a literature search, we only found five articles on total knee arthroplasty for Charcot joints (1–5). We did not find a single article dealing with alternative treatment options or the general clinical course of this disease. We started our study

"Why are you crying? You got what you wanted!": Psychosocial experiences of sex reassignment surgery

Little is known about the psychosocial needs of trans individuals as they make the surgical transition to their preferred gender. This qualitative study explored the lived experiences of 14 Australian trans men and women, aged between 25 and 78 who had undergone sex reassignment surgery to determine if their needs were met. The key findings suggest that while the surgery met their personal needs, there are inconsistencies in the level of care and support provided at the medical level throughout the transition process. In legal terms, the complex legislative framework does little but increase the psychosocial burden of Australian trans people.

Structural-stratigraphic reconstruction of the lower Whakataki formation, north island, New Zealand

This thesis details a Miocene aged sedimentary rock formation located in north island New Zealand. Mapping, stratigraphic logging and petrographic analysis of the rock formation ascertained that it was deposited in a deep-marine, tectonically active region. The work details the make-up of the sedimentary rocks using geochemistry and microscopy to define their origin. This definition was used to interpret the depositional model of the sediments detailing how they were transported and how they were emplaced.

Reconstruction of the ocular surface using biomaterial templates

This chapter discusses the effect on vision of a large group of pathological conditions, known as ocular surface disorders (OSDs), and presents the therapeutic strategies to reconstruct the abnormal ocular surface. If left untreated, most of the OSDs will lead to partial or total loss of eyesight, especially when limbal stem cell deficiency is involved. An overview of various treatment strategies is presented, with the emphasis on the development of the ex vivo expansion of corneal limbal epithelial cells (presumed to be progenitor or stem cells) and the creation of transplantable epithelial constructs. The use of naturally derived biomaterials (collagen, fibrin, amnion, etc.) or synthetic polymers (polylactides, thermoresponsive polymers, etc.) as substrata in these constructs is critically analyzed. Emphasis is placed on the templates from silk proteins, which are being developed by the authors.

La norme du corps hybride : Une éthique de la reconstruction et de l'amélioration du corps humain en chirurgie

Aujourd'hui, techniques et technologies interagissent avec le corps humain et donnent aux personnes la possibilité de reconstruire leur corps, mais aussi de l'améliorer et de l'augmenter. L'hybridation est un processus technologique visant à compenser les défaillances humaines. L'augmentation de la puissance d'être est exaltée (santé, sexualité, performance, jeunesse), pourtant son accès n'est pas pour tous. Ce livre propose de démêler les différentes représentations du corps hybride et les projets qui les sous-tendent.

Investigating the effect of Eye Movement Desensitization and Reprocessing (EMDR) on postoperative pain intensity in adolescents undergoing surgery: A randomized controlled trial

Aim To investigate the efficacy of Eye Movement Desensitization and Reprocessing for postoperative pain management in adolescents. Background Eye Movement Desensitization and Reprocessing is an inexpensive, non-pharmacological intervention that has successfully been used to treat chronic pain. It holds promise in the treatment of acute, postsurgical pain based on its purported effects on the brain and nervous system. Design A randomized controlled trial was used. Methods Fifty-six adolescent surgical patients aged between 12-18 years were allocated to gender-balanced Eye Movement Desensitization and Reprocessing (treatment) or non-Eye Movement Desensitization and Reprocessing (control) groups. Pain was measured using the Wong-Baker FACES® Pain Rating Scale (WBFS) before and after the intervention (or non-intervention for the control group). Findings A Wilcoxon signed-rank test demonstrated that the Eye Movement Desensitization and Reprocessing group experienced a significant reduction in pain intensity after treatment intervention, whereas the control group did not. Additionally, a Mann–Whitney U-test showed that, while there was no significant difference between the two groups at time 1, there was a significant difference in pain intensity between the two groups at time 2, with the Eye Movement Desensitization and Reprocessing group experiencing lower levels of pain. Conclusion These results suggest that Eye Movement Desensitization and Reprocessing may be an effective treatment modality for postoperative pain.