62 research outputs found

    PLIKS: A Pseudo-Linear Inverse Kinematic Solver for 3D Human Body Estimation

    Full text link
    We consider the problem of reconstructing a 3D mesh of the human body from a single 2D image as a model-in-the-loop optimization problem. Existing approaches often regress the shape, pose, and translation parameters of a parametric statistical model assuming a weak-perspective camera. In contrast, we first estimate 2D pixel-aligned vertices in image space and propose PLIKS (Pseudo-Linear Inverse Kinematic Solver) to regress the model parameters by minimizing a linear least squares problem. PLIKS is a linearized formulation of the parametric SMPL model, which provides an optimal pose and shape solution from an adequate initialization. Our method is based on analytically calculating an initial pose estimate from the network predicted 3D mesh followed by PLIKS to obtain an optimal solution for the given constraints. As our framework makes use of 2D pixel-aligned maps, it is inherently robust to partial occlusion. To demonstrate the performance of the proposed approach, we present quantitative evaluations which confirm that PLIKS achieves more accurate reconstruction with greater than 10% improvement compared to other state-of-the-art methods with respect to the standard 3D human pose and shape benchmarks while also obtaining a reconstruction error improvement of 12.9 mm on the newer AGORA dataset

    Fully-automatic CT data preparation for interventional X-ray skin dose simulation

    Full text link
    Recently, deep learning (DL) found its way to interventional X-ray skin dose estimation. While its performance was found to be acceptable, even more accurate results could be achieved if more data sets were available for training. One possibility is to turn to computed tomography (CT) data sets. Typically, computed tomography (CT) scans can be mapped to tissue labels and mass densities to obtain training data. However, care has to be taken to make sure that the different clinical settings are properly accounted for. First, the interventional environment is characterized by wide variety of table setups that are significantly different from the typical patient tables used in conventional CT. This cannot be ignored, since tables play a crucial role in sound skin dose estimation in an interventional setup, e. g., when the X-ray source is directly underneath a patient (posterior-anterior view). Second, due to interpolation errors, most CT scans do not facilitate a clean segmentation of the skin border. As a solution to these problems, we applied connected component labeling (CCL) and Canny edge detection to (a) robustly separate the patient from the table and (b) to identify the outermost skin layer. Our results show that these extensions enable fully-automatic, generalized pre-processing of CT scans for further simulation of both skin dose and corresponding X-ray projections.Comment: 6 pages, 4 figures, Bildverarbeitung f\"ur die Medizin 2020, code will be accessible soon (url

    Vitamin D3 and 25-Hydroxyvitamin D3 Content of Retail White Fish and Eggs in Australia

    Get PDF
    Dietary vitamin D may compensate for inadequate sun exposure; however, there have been few investigations into the vitamin D content of Australian foods. We measured vitamin D3 and 25-hydroxyvitamin D3 (25(OH)D3) in four species of white fish (barramundi, basa, hoki and king dory), and chicken eggs (cage and free-range), purchased from five Australian cities. Samples included local, imported and wild-caught fish, and eggs of varying size from producers with a range of hen stocking densities. Raw and cooked samples were analysed using high performance liquid chromatography with photodiode array. Limits of reporting were 0.2 and 0.1 µg/100 g for vitamin D3 and 25(OH)D3, respectively. The vitamin D3 content of cooked white fish ranged from <0.1 to 2.3 µg/100 g, and the 25(OH)D3 content ranged from 0.3 to 0.7 µg/100 g. The vitamin D3 content of cooked cage eggs ranged from 0.4 to 0.8 µg/100 g, and the 25(OH)D3 content ranged from 0.4 to 1.2 µg/100 g. The vitamin D3 content of cooked free-range eggs ranged from 0.3 to 2.2 µg/100 g, and the 25(OH)D3 content ranged from 0.5 to 0.8 µg/100 g. If, as has been suggested, 25(OH)D3 has five times greater bioactivity than vitamin D3, one cooked serve (100 g) of white fish, and one cooked serve of cage or free-range eggs (120 g) may provide 50% or 100%, respectively, of the current guidelines for the adequate intake of vitamin D (5 µg) for Australians aged 1-50 years

    The mechanism of intramolecular energy transfer in terminally substituted polyene molecules

    Get PDF
    Absorption, fluorescence and excitation spectra of different terminally substituted polyenes have been recorded in the UV-Vis region. The observed intramolecular unidirectional energy transfer from a donor substituent to an acceptor at the other end of the chain is influenced but not inhibited by incorporation of a spacer into the polyene chain. In molecules without a spacer, internal conversion within the supermolecule can explain the observed transfer of energy. In molecules with a spacer interrupting the polyene chain the observed intramolecular energy transfer can be explained in terms of Förster transfer

    Holocene Temperature Variations in Semi-Arid Central Mongolia—A Chronological and Sedimentological Perspective From a 7400-year Lake Sediment Record From the Khangai Mountains

    Get PDF
    Semi-arid Mongolia is a highly sensitive region to climate changes, but the region’s Holocene paleoclimatic evolution and its underlying forcing mechanisms have been the subject of much recent debate. Here we present a continuous 7.4 ka sediment record from the high-altitude Shireet Naiman Nuur (Nuur = lake) in the central Mongolian Khangai Mountains. We extensively dated the sediments and analyzed elemental composition and bulk isotopes for lake sediment characterization. Our results show that 14C-dating of bulk organic carbon and terrestrial macrofossils provide a robust and precise chronology for the past 7.4 ± 0.3 cal ka BP at Shireet Naiman Nuur and 14C-ages are mostly in stratigraphic order. The 14C-based chronology is confirmed by paleomagnetic secular variations, which resemble the predictions of spherical harmonic geomagnetic field models. The very good chronological control makes paleomagnetic secular variation stratigraphy a powerful tool for evaluating and refining regional 14C-chronologies when compared to the record presented here. The lake sediment proxies TOC, N, log (Ca/Ti) and log (Si/Ti) reveal increased lake primary productivity and high growing season temperatures from 7.4 ± 0.3 to 4.3 ± 0.2 cal ka BP, which is likely the result of stronger summer insolation and pronounced warming. Reduced summer insolation thereafter results in decreased productivity and low growing season temperatures at Shireet Naiman Nuur from 4.3 ± 0.3 cal ka BP until present day. The globally acknowledged 4.2 ka event also appears as a pronounced cooling event at Shireet Naiman Nuur, and additional abrupt cooling events occurred during minima in total solar irradiance at ~3.4, 2.8 and 2.4 ka BP. Low lake primary productivity and growing season temperatures are likely the result of longer ice cover periods at the high-altitude (2,429m a.s.l.) Shireet Naiman Nuur. This leads to shorter mixing periods of the lake water which is supported by more positive δ13CTOC because of increased incorporation of dissolved HCO3− by aquatic producers during periods of longer ice cover

    Vitamin D3 and 25-hydroxyvitamin D3 content of retail white fish and eggs in Australia

    Get PDF
    Dietary vitamin D may compensate for inadequate sun exposure; however, there have been few investigations into the vitamin D content of Australian foods. We measured vitamin D3 and 25-hydroxyvitamin D3 (25(OH)D3) in four species of white fish (barramundi, basa, hoki and king dory), and chicken eggs (cage and free-range), purchased from five Australian cities. Samples included local, imported and wild-caught fish, and eggs of varying size from producers with a range of hen stocking densities. Raw and cooked samples were analysed using high performance liquid chromatography with photodiode array. Limits of reporting were 0.2 and 0.1 μg/100 g for vitamin D3 and 25(OH)D3, respectively. The vitamin D3 content of cooked white fish ranged from <0.1 to 2.3 μg/100 g, and the 25(OH)D3 content ranged from 0.3 to 0.7 μg/100 g. The vitamin D3 content of cooked cage eggs ranged from 0.4 to 0.8 μg/100 g, and the 25(OH)D3 content ranged from 0.4 to 1.2 μg/100 g. The vitamin D3 content of cooked free-range eggs ranged from 0.3 to 2.2 μg/100 g, and the 25(OH)D3 content ranged from 0.5 to 0.8 μg/100 g. If, as has been suggested, 25(OH)D3 has five times greater bioactivity than vitamin D3, one cooked serve (100 g) of white fish, and one cooked serve of cage or free-range eggs (120 g) may provide 50% or 100%, respectively, of the current guidelines for the adequate intake of vitamin D (5 µg) for Australians aged 1–50 years. View Full-Text Keywords: food composition data; vitamin D3; 25-hydroxyvitamin D3; fish; eggsSample purchase, preparation and analysis was funded by the Western Australia Department of Health. L.J.B is funded by a Curtin University Research Fellowship; R.M.L is funded by a NHMRC Senior Research Fellowship
    • …
    corecore