405 resultados para Chamoiseau, Patrick
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The Australian Bone Marrow Donor Registry (ABMDR) is a publicly funded company that is part of an international network that facilitates unrelated bone marrow transplantation. This role means that the ABMDR has access to a large biospecimen repository, therefore making it a highly valuable research resource. Recognising the potential value of these biospecimens for research purposes, the ABMDR is in the process of determining whether, and how, to share its biospecimens with other biobanks. While this would undoubtedly be of value to the scientific community, and ultimately to the wider community, it would also inevitably transform the role of an institution whose primary role is therapeutic, and would compromise the degree of control that a custodian has over donated material. This article describe the challenges confronting the ABMDR, and organisations like it, in balancing their duties to donors, patients, researchers and the general public. These problems have led inevitably to the use of "property" rights language in the discussion of these issues but notions of gift, ownership, trusteeship and transfer might also be considered.
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Achieving energy efficient legged locomotion is an important goal for the future of robot mobility. This paper presents a novel joint for legged locomotion that is energy efficient for two reasons. The first reason is the configuration of the elastic elements and actuator which we show analytically has lower energy losses than the typical arrangement. The second is that the joint stiffness, and hence stance duration, is controllable without requiring any energy from the actuator. Further, the joint stiffness can be changed significantly during the flight phase, from zero to highly rigid. Results obtained from a prototype hopper, demonstrate that the joint allows continuous and peak hopping via torque control. The results also demonstrate that the hopping frequency can be varied between 2.2Hz and 4.6Hz with associated stance duration of between 0.35 and 0.15 seconds.
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Due to the demand for better and deeper analysis in sports, organizations (both professional teams and broadcasters) are looking to use spatiotemporal data in the form of player tracking information to obtain an advantage over their competitors. However, due to the large volume of data, its unstructured nature, and lack of associated team activity labels (e.g. strategic/tactical), effective and efficient strategies to deal with such data have yet to be deployed. A bottleneck restricting such solutions is the lack of a suitable representation (i.e. ordering of players) which is immune to the potentially infinite number of possible permutations of player orderings, in addition to the high dimensionality of temporal signal (e.g. a game of soccer last for 90 mins). Leveraging a recent method which utilizes a "role-representation", as well as a feature reduction strategy that uses a spatiotemporal bilinear basis model to form a compact spatiotemporal representation. Using this representation, we find the most likely formation patterns of a team associated with match events across nearly 14 hours of continuous player and ball tracking data in soccer. Additionally, we show that we can accurately segment a match into distinct game phases and detect highlights. (i.e. shots, corners, free-kicks, etc) completely automatically using a decision-tree formulation.
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Over the past decade, vision-based tracking systems have been successfully deployed in professional sports such as tennis and cricket for enhanced broadcast visualizations as well as aiding umpiring decisions. Despite the high-level of accuracy of the tracking systems and the sheer volume of spatiotemporal data they generate, the use of this high quality data for quantitative player performance and prediction has been lacking. In this paper, we present a method which predicts the location of a future shot based on the spatiotemporal parameters of the incoming shots (i.e. shot speed, location, angle and feet location) from such a vision system. Having the ability to accurately predict future short-term events has enormous implications in the area of automatic sports broadcasting in addition to coaching and commentary domains. Using Hawk-Eye data from the 2012 Australian Open Men's draw, we utilize a Dynamic Bayesian Network to model player behaviors and use an online model adaptation method to match the player's behavior to enhance shot predictability. To show the utility of our approach, we analyze the shot predictability of the top 3 players seeds in the tournament (Djokovic, Federer and Nadal) as they played the most amounts of games.
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At the highest level of competitive sport, nearly all performances of athletes (both training and competitive) are chronicled using video. Video is then often viewed by expert coaches/analysts who then manually label important performance indicators to gauge performance. Stroke-rate and pacing are important performance measures in swimming, and these are previously digitised manually by a human. This is problematic as annotating large volumes of video can be costly, and time-consuming. Further, since it is difficult to accurately estimate the position of the swimmer at each frame, measures such as stroke rate are generally aggregated over an entire swimming lap. Vision-based techniques which can automatically, objectively and reliably track the swimmer and their location can potentially solve these issues and allow for large-scale analysis of a swimmer across many videos. However, the aquatic environment is challenging due to fluctuations in scene from splashes, reflections and because swimmers are frequently submerged at different points in a race. In this paper, we temporally segment races into distinct and sequential states, and propose a multimodal approach which employs individual detectors tuned to each race state. Our approach allows the swimmer to be located and tracked smoothly in each frame despite a diverse range of constraints. We test our approach on a video dataset compiled at the 2012 Australian Short Course Swimming Championships.
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Robust descriptor matching across varying lighting conditions is important for vision-based robotics. We present a novel strategy for quantifying the lighting variance of descriptors. The strategy works by utilising recovered low dimensional mappings from Isomap and our measure of the lighting variance of each of these mappings. The resultant metric allows different descriptors to be compared given a dataset and a set of keypoints. We demonstrate that the SIFT descriptor typically has lower lighting variance than other descriptors, although the result depends on semantic class and lighting conditions.
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This paper presents a pose estimation approach that is resilient to typical sensor failure and suitable for low cost agricultural robots. Guiding large agricultural machinery with highly accurate GPS/INS systems has become standard practice, however these systems are inappropriate for smaller, lower-cost robots. Our positioning system estimates pose by fusing data from a low-cost global positioning sensor, low-cost inertial sensors and a new technique for vision-based row tracking. The results first demonstrate that our positioning system will accurately guide a robot to perform a coverage task across a 6 hectare field. The results then demonstrate that our vision-based row tracking algorithm improves the performance of the positioning system despite long periods of precision correction signal dropout and intermittent dropouts of the entire GPS sensor.
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Introduction The clinically known importance of patient sex as a major risk factor for compromised bone healing is poorly reflected in animal models. Consequently, the underlying cellular mechanisms remain elusive. Because mesenchymal stem cells (MSCs) are postulated to regulate tissue regeneration and give rise to essential differentiated cell types, they may contribute to sex-specific differences in bone healing outcomes. Methods We investigated sex-specific variations in bone healing and associated differences in MSC populations. A 1.5 mm osteotomy gap in the femora of 8 male and 8 female 12-month-old Sprague-Dawley rats was stabilized by an external fixator. Healing was analyzed in terms of biomechanical testing, bridging and callus size over time (radiography at 2, 4, and 6 weeks after surgery), and callus volume and geometry by μCT at final follow-up. MSCs were obtained from bone marrow samples of an age-matched group of 12 animals (6 per gender) and analyzed for numbers of colony-forming units (CFUs) and their capacity to differentiate and proliferate. The proportion of senescent cells was determined by β-galactosidase staining. Results Sex-specific differences were indicated by a compromised mechanical competence of the callus in females compared with males (maximum torque at failure, p = 0.028). Throughout the follow-up, the cross-sectional area of callus relative to bone was reduced in females (p ≤ 0.01), and the bridging of callus was delayed (p 2weeks = 0.041). μCT revealed a reduced callus size (p = 0.003), mineralization (p = 0.003) and polar moment of inertia (p = 0.003) in female animals. The female bone marrow contained significantly fewer MSCs, represented by low CFU numbers in both femora and tibiae (p femur = 0.017, p tibia = 0.010). Functional characteristics of male and female MSCs were similar. Conclusion Biomechanically compromised and radiographically delayed bone formation were distinctive in female rats. These differences were concomitant with a reduced number of MSCs, which may be causative for the suboptimal bone healing.
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Integrated psychological treatment addressing co-existing alcohol misuse and depression has not been compared with single-focused treatment. This trial evaluates changes over 36 months following randomization of 284 outpatients to one of four motivational interviewing and cognitive-behavior therapy (MICBT) based interventions: (1) brief integrated intervention (BI); or BI plus 9 further sessions with (2) an integrated-, (3) alcohol-, or (4) depression-focus. Outcome measures included changes in alcohol consumption, depression (BDI-II: Beck Depression Inventory) and functioning (GAF: Global Assessment of Functioning), with average improvements from baseline of 21.8 drinks per week, 12.6 BDI-II units and 8.2 GAF units. Longer interventions tended to be more effective in reducing depression and improving functioning in the long-term, and in improving alcohol consumption in the short-term. Integrated treatment was at least as good as single-focused MICBT. Alcohol-focused treatment was as effective as depression-focused treatment at reducing depression and more effective in reducing alcohol misuse. The best approach seems to be an initial focus on both conditions followed by additional integrated- or alcohol-focused sessions.
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This thesis examined the relationship between firms' corporate reputation and their future financial performance. Corporate reputation was represented by measuring the level of senior executives' attention to a number of intangible firm' resources (e.g. financial reputation, service culture) within firms' annual reports over a 17 year period. Initial findings suggested there was only a small relationship between reputation and future performance which lead to a reformulation of the problem. Reputation was posited to be a source of corporate resilience that helped firms with stronger reputations to sustain superior financial performance in times of difficulty, as well as allowing them to rebound more quickly from performance decline. Results suggest this interpretation of corporate reputation as well as indicating that industry sectors operate in different reputational 'domains' in which the relative importance of financial versus stakeholder aspects of corporate reputation varies.
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Changes in dendritic spine number and shape are believed to reflect structural plasticity consequent to learning. Previous studies have strongly suggested that the dorsal subnucleus of the lateral amygdala is an important site of physiological plasticity in Pavlovian fear conditioning. In the present study, we examined the effect of auditory fear conditioning on dendritic spine numbers in the dorsal subnucleus of the lateral amygdala using an immunolabelling procedure to visualize the spine-associated protein spinophilin. Associatively conditioned rats that received paired tone and shock presentations had 35% more total spinophilin-immunoreactive spines than animals that had unpaired stimulation, consistent with the idea that changes in the number of dendritic spines occur during learning and account in part for memory.
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Synapses onto dendritic spines in the lateral amygdala formed by afferents from the auditory thalamus represent a site of plasticity in Pavlovian fear conditioning. Previous work has demonstrated that thalamic afferents synapse onto LA spines expressing glutamate receptor (GluR) subunits, but the GluR subunit distribution at the synapse and within the cytoplasm has not been characterized. Therefore, we performed a quantitative analysis for α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptor subunits GluR2 and GluR3 and N-methyl-D-aspartate (NMDA) receptor subunits NR1 and NR2B by combining anterograde labeling of thalamo-amygdaloid afferents with postembedding immunoelectron microscopy for the GluRs in adult rats. A high percentage of thalamo- amygdaloid spines was immunoreactive for GluR2 (80%), GluR3 (83%), and NR1 (83%), while a smaller proportion of spines expressed NR2B (59%). To compare across the various subunits, the cytoplasmic to synaptic ratios of GluRs were measured within thalamo-amygdaloid spines. Analyses revealed that the cytoplasmic pool of GluR2 receptors was twice as large compared to the GluR3, NR1, and NR2B subunits. Our data also show that in the adult brain, the NR2B subunit is expressed in the majority of in thalamo-amygdaloid spines and that within these spines, the various GluRs are differentially distributed between synaptic and non-synaptic sites. The prevalence of the NR2B subunit in thalamo-amygdaloid spines provides morphological evidence supporting its role in the fear conditioning circuit while the differential distribution of the GluR subtypes may reflect distinct roles for their involvement in this circuitry and synaptic plasticity.
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The molecular mechanisms involved in non‑small cell lung cancer tumourigenesis are largely unknown; however, recent studies have suggested that long non-coding RNAs (lncRNAs) are likely to play a role. In this study, we used public databases to identify an mRNA-like, candidate long non-coding RNA, GHSROS (GHSR opposite strand), transcribed from the antisense strand of the ghrelin receptor gene, growth hormone secretagogue receptor (GHSR). Quantitative real-time RT-PCR revealed higher expression of GHSROS in lung cancer tissue compared to adjacent, non-tumour lung tissue. In common with many long non-coding RNAs, GHSROS is 5' capped and 3' polyadenylated (mRNA-like), lacks an extensive open reading frame and harbours a transposable element. Engineered overexpression of GHSROS stimulated cell migration in the A549 and NCI-H1299 non-small cell lung cancer cell lines, but suppressed cell migration in the Beas-2B normal lung-derived bronchoepithelial cell line. This suggests that GHSROS function may be dependent on the oncogenic context. The identification of GHSROS, which is expressed in lung cancer and stimulates cell migration in lung cancer cell lines, contributes to the growing number of non-coding RNAs that play a role in the regulation of tumourigenesis and metastatic cancer progression.
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Surveying 1,700 journalists from seventeen countries, this study investigates perceived influences on news work. Analysis reveals a dimensional structure of six distinct domains—political, economic, organizational, professional, and procedural influences, as well as reference groups. Across countries, these six dimensions build up a hierarchical structure where organizational, professional, and procedural influences are perceived as more powerful limits to journalists' work than political and economic influences.