7,000 research outputs found

    Unwind: Interactive Fish Straightening

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    The ScanAllFish project is a large-scale effort to scan all the world's 33,100 known species of fishes. It has already generated thousands of volumetric CT scans of fish species which are available on open access platforms such as the Open Science Framework. To achieve a scanning rate required for a project of this magnitude, many specimens are grouped together into a single tube and scanned all at once. The resulting data contain many fish which are often bent and twisted to fit into the scanner. Our system, Unwind, is a novel interactive visualization and processing tool which extracts, unbends, and untwists volumetric images of fish with minimal user interaction. Our approach enables scientists to interactively unwarp these volumes to remove the undesired torque and bending using a piecewise-linear skeleton extracted by averaging isosurfaces of a harmonic function connecting the head and tail of each fish. The result is a volumetric dataset of a individual, straight fish in a canonical pose defined by the marine biologist expert user. We have developed Unwind in collaboration with a team of marine biologists: Our system has been deployed in their labs, and is presently being used for dataset construction, biomechanical analysis, and the generation of figures for scientific publication

    Biomechanics of foetal movement.

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    © 2015, AO Research Institute. All rights reserved.Foetal movements commence at seven weeks of gestation, with the foetal movement repertoire including twitches, whole body movements, stretches, isolated limb movements, breathing movements, head and neck movements, jaw movements (including yawning, sucking and swallowing) and hiccups by ten weeks of gestational age. There are two key biomechanical aspects to gross foetal movements; the first being that the foetus moves in a dynamically changing constrained physical environment in which the freedom to move becomes increasingly restricted with increasing foetal size and decreasing amniotic fluid. Therefore, the mechanical environment experienced by the foetus affects its ability to move freely. Secondly, the mechanical forces induced by foetal movements are crucial for normal skeletal development, as evidenced by a number of conditions and syndromes for which reduced or abnormal foetal movements are implicated, such as developmental dysplasia of the hip, arthrogryposis and foetal akinesia deformation sequence. This review examines both the biomechanical effects of the physical environment on foetal movements through discussion of intrauterine factors, such as space, foetal positioning and volume of amniotic fluid, and the biomechanical role of gross foetal movements in human skeletal development through investigation of the effects of abnormal movement on the bones and joints. This review also highlights computational simulations of foetal movements that attempt to determine the mechanical forces acting on the foetus as it moves. Finally, avenues for future research into foetal movement biomechanics are highlighted, which have potential impact for a diverse range of fields including foetal medicine, musculoskeletal disorders and tissue engineering

    Violence indicators in Quebrada de Humahuaca, Jujuy, Argentina: The Regional Development Period from a regional perspective

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    Quebrada de Humahuaca (Jujuy, Argentina) has been extensively studied by archaeologists. Studies have been focused mainly on the Late Regional Development Period (1250 1430 AD), which has been defined as a time of social conflict. In this paper we present bioarchaeological evidence of interper-sonal violence related trauma found in populations of the region. A sample of 153 skulls from three sites of Quebrada de Humahuaca: Los Amarillos, La Huerta and Yacoraite, were analyzed, differentiating antemortem and perimortem fractures, cut marks as well as the presence of trophy skulls. The results were subjected to nonparametric statistical tests, in order to assess inter-site level differences, sex and age distribution. Bioarchaeological analysis determined a high frequency of interpersonal violence related trauma. Most registered injuries belonged to the antemortem type, demonstrating that the individuals of those events that had generated said cranial trauma had managed to survive. Interpersonal violence affected both men and women the same, registering no differences in neither sex nor age group, however evidence of trauma varied geographically from site to site. Statistical calculations reveal that the Yacoraite site is where the highest frequency of trauma was found, while La Huerta is where the highest level of trophy skulls was registered.Fil: Seldes, Verónica. Universidad de Buenos Aires. Facultad de Filosofía y Letras. Departamento de Ciencias Antropológicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Botta, Florencia Natalia. Universidad de Buenos Aires. Facultad de Filosofía y Letras; Argentin

    Embodied Interactions for Spatial Design Ideation: Symbolic, Geometric, and Tangible Approaches

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    Computer interfaces are evolving from mere aids for number crunching into active partners in creative processes such as art and design. This is, to a great extent, the result of mass availability of new interaction technology such as depth sensing, sensor integration in mobile devices, and increasing computational power. We are now witnessing the emergence of maker culture that can elevate art and design beyond the purview of enterprises and professionals such as trained engineers and artists. Materializing this transformation is not trivial; everyone has ideas but only a select few can bring them to reality. The challenge is the recognition and the subsequent interpretation of human actions into design intent

    Fast Simulation of Skin Sliding

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    Skin sliding is the phenomenon of the skin moving over underlying layers of fat, muscle and bone. Due to the complex interconnections between these separate layers and their differing elasticity properties, it is difficult to model and expensive to compute. We present a novel method to simulate this phenomenon at real--time by remeshing the surface based on a parameter space resampling. In order to evaluate the surface parametrization, we borrow a technique from structural engineering known as the force density method which solves for an energy minimizing form with a sparse linear system. Our method creates a realistic approximation of skin sliding in real--time, reducing texture distortions in the region of the deformation. In addition it is flexible, simple to use, and can be incorporated into any animation pipeline

    Fourteenth Biennial Status Report: März 2017 - February 2019

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    Senescence: An Aging based Character Simulation Framework

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    The \u27Senescence\u27 framework is a character simulation plug-in for Maya that can be used for rigging and skinning muscle deformer based humanoid characters with support for aging. The framework was developed using Python, Maya Embedded Language and PyQt. The main targeted users for this framework are the Character Technical Directors, Technical Artists, Riggers and Animators from the production pipeline of Visual Effects Studios. The characters that were simulated using \u27Senescence\u27 were studied using a survey to understand how well the intended age was perceived by the audience. The results of the survey could not reject one of our null hypotheses which means that the difference in the simulated age groups of the character is not perceived well by the participants. But, there is a difference in the perception of simulated age in the character between an Animator and a Non-Animator. Therefore, the difference in the simulated character\u27s age was perceived by an untrained audience, but the audience was unable to relate it to a specific age group
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