Literatura científica selecionada sobre o tema "Whole-body rotations"
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Artigos de revistas sobre o assunto "Whole-body rotations"
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Blouin, J., J. L. Vercher, G. M. Gauthier, J. Paillard, C. Bard e Y. Lamarre. "Perception of passive whole-body rotations in the absence of neck and body proprioception". Journal of Neurophysiology 74, n.º 5 (1 de novembro de 1995): 2216–19. http://dx.doi.org/10.1152/jn.1995.74.5.2216.
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1. This study investigated whether accurate perception of body rotation after passive horizontal whole-body rotations in the dark requires the integration of both vestibular and neck-body proprioceptive signals. 2. In the first experiment, the gain of the vestibuloocular reflex (VOR) of normal subjects ("controls") and of a patient without proprioception of the neck and body muscles was assessed by the use of pulse and sinusoidal stimulation. In the second experiment, the subjects reported verbally the magnitude of the body rotations. Finally, in the third experiment, they shifted gaze to the position fixated before the rotation ("vestibular memory-contingent saccades" paradigm). 3. The VOR gain of the patient was similar to that of controls, although the body rotations of the patient were largely overestimated, regardless of whether the patient reported the perceived magnitude verbally or through a gaze shift toward the position gazed at before the rotation. 4. These results suggest that neck muscle proprioception contributes to the vestibular signal calibration at the perceptual level necessary for determining body orientation accurately after rotations in the dark.
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Lopez, Christophe, Dominique Vibert e Fred W. Mast. "Can imagined whole-body rotations improve vestibular compensation?" Medical Hypotheses 76, n.º 6 (junho de 2011): 816–19. http://dx.doi.org/10.1016/j.mehy.2011.02.026.
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Bockisch, Christopher J., Dominik Straumann e Thomas Haslwanter. "Eye Movements During Multi-Axis Whole-Body Rotations". Journal of Neurophysiology 89, n.º 1 (1 de janeiro de 2003): 355–66. http://dx.doi.org/10.1152/jn.00058.2002.
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The semi-circular canals and the otolith organs both contribute to gaze stabilization during head movement. We investigated how these sensory signals interact when they provide conflicting information about head orientation in space. Human subjects were reoriented 90° in pitch or roll during long-duration, constant-velocity rotation about the earth-vertical axis while we measured three-dimensional eye movements. After the reorientation, the otoliths correctly indicated the static orientation of the subject with respect to gravity, while the semicircular canals provided a strong signal of rotation. This rotation signal from the canals could only be consistent with a static orientation with respect to gravity if the rotation-axis indicated by the canals was exactly parallel to gravity. This was not true, so a cue-conflict existed. These conflicting stimuli elicited motion sickness and a complex tumbling sensation. Strong horizontal, vertical, and/or torsional eye movements were also induced, allowing us to study the influence of the conflict between the otoliths and the canals on all three eye-movement components. We found a shortening of the horizontal and vertical time constants of the decay of nystagmus and a trend for an increase in peak velocity following reorientation. The dumping of the velocity storage occurred regardless of whether eye velocity along that axis was compensatory to the head rotation or not. We found a trend for the axis of eye velocity to reorient to make the head-velocity signal from the canals consistent with the head-orientation signal from the otoliths, but this reorientation was small and only observed when subjects were tilted to upright. Previous models of canal-otolith interaction could not fully account for our data, particularly the decreased time constant of the decay of nystagmus. We present a model with a mechanism that reduces the velocity-storage component in the presence of a strong cue-conflict. Our study, supported by other experiments, also indicates that static otolith signals exhibit considerably smaller effects on eye movements in humans than in monkeys.
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Klier, Eliana M., Dora E. Angelaki e Bernhard J. M. Hess. "Human Visuospatial Updating After Noncommutative Rotations". Journal of Neurophysiology 98, n.º 1 (julho de 2007): 537–41. http://dx.doi.org/10.1152/jn.01229.2006.
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As we move our bodies in space, we often undergo head and body rotations about different axes—yaw, pitch, and roll. The order in which we rotate about these axes is an important factor in determining the final position of our bodies in space because rotations, unlike translations, do not commute. Does our brain keep track of the noncommutativity of rotations when computing changes in head and body orientation and then use this information when planning subsequent motor commands? We used a visuospatial updating task to investigate whether saccades to remembered visual targets are accurate after intervening, whole-body rotational sequences. The sequences were reversed, either yaw then roll or roll then yaw, such that the final required eye movements to reach the same space-fixed target were different in each case. While each subject performed consistently irrespective of target location and rotational combination, we found great intersubject variability in their capacity to update. The distance between the noncommutative endpoints was, on average, half of that predicted by perfect noncommutativity. Nevertheless, most subjects did make eye movements to distinct final endpoint locations and not to one unique location in space as predicted by a commutative model. In addition, their noncommutative performance significantly improved when their less than ideal updating performance was taken into account. Thus the brain can produce movements that are consistent with the processing of noncommutative rotations, although it is often poor in using internal estimates of rotation for updating.
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Van Pelt, S., J. A. M. Van Gisbergen e W. P. Medendorp. "Visuospatial Memory Computations During Whole-Body Rotations in Roll". Journal of Neurophysiology 94, n.º 2 (agosto de 2005): 1432–42. http://dx.doi.org/10.1152/jn.00018.2005.
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We used a memory-saccade task to test whether the location of a target, briefly presented before a whole-body rotation in roll, is stored in egocentric or in allocentric coordinates. To make this distinction, we exploited the fact that subjects, when tilted sideways in darkness, make systematic errors when indicating the direction of gravity (an allocentric task) even though they have a veridical percept of their self-orientation in space. We hypothesized that if spatial memory is coded allocentrically, these distortions affect the coding of remembered targets and their readout after a body rotation. Alternatively, if coding is egocentric, updating for body rotation becomes essential and errors in performance should be related to the amount of intervening rotation. Subjects ( n = 6) were tested making saccades to remembered world-fixed targets after passive body tilts. Initial and final tilt angle ranged between −120° CCW and 120° CW. The results showed that subjects made large systematic directional errors in their saccades (up to 90°). These errors did not occur in the absence of intervening body rotation, ruling out a memory degradation effect. Regression analysis showed that the errors were closely related to the amount of subjective allocentric distortion at both the initial and final tilt angle, rather than to the amount of intervening rotation. We conclude that the brain uses an allocentric reference frame, possibly gravity-based, to code visuospatial memories during whole-body tilts. This supports the notion that the brain can define information in multiple frames of reference, depending on sensory inputs and task demands.
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Dumontheil, Iroise, Panagiota Panagiotaki e Alain Berthoz. "Dual adaptation to sensory conflicts during whole-body rotations". Brain Research 1072, n.º 1 (fevereiro de 2006): 119–32. http://dx.doi.org/10.1016/j.brainres.2005.11.091.
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Falconer, Caroline J., e Fred W. Mast. "Balancing the Mind". Experimental Psychology 59, n.º 6 (1 de janeiro de 2012): 332–39. http://dx.doi.org/10.1027/1618-3169/a000161.
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The body schema is a key component in accomplishing egocentric mental transformations, which rely on bodily reference frames. These reference frames are based on a plurality of different cognitive and sensory cues among which the vestibular system plays a prominent role. We investigated whether a bottom-up influence of vestibular stimulation modulates the ability to perform egocentric mental transformations. Participants were significantly faster to make correct spatial judgments during vestibular stimulation as compared to sham stimulation. Interestingly, no such effects were found for mental transformation of hand stimuli or during mental transformations of letters, thus showing a selective influence of vestibular stimulation on the rotation of whole-body reference frames. Furthermore, we found an interaction with the angle of rotation and vestibular stimulation demonstrating an increase in facilitation during mental body rotations in a direction congruent with rightward vestibular afferents. We propose that facilitation reflects a convergence in shared brain areas that process bottom-up vestibular signals and top-down imagined whole-body rotations, including the precuneus and tempero-parietal junction. Ultimately, our results show that vestibular information can influence higher-order cognitive processes, such as the body schema and mental imagery.
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Glasauer, Stefan, e Thomas Brandt. "Noncommutative Updating of Perceived Self-Orientation in Three Dimensions". Journal of Neurophysiology 97, n.º 4 (abril de 2007): 2958–64. http://dx.doi.org/10.1152/jn.00655.2006.
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After whole body rotations around an earth-vertical axis in darkness, subjects can indicate their orientation in space with respect to their initial orientation reasonably well. This is possible because the brain is able to mathematically integrate self-velocity information provided by the vestibular system to obtain self-orientation, a process called path integration. For rotations around multiple axes, however, computations are more demanding to accurately update self-orientation with respect to space. In such a case, simple integration is no longer sufficient because of the noncommutativity of rotations. We investigated whether such updating is possible after three-dimensional whole body rotations and whether the noncommutativity of three-dimensional rotations is taken into account. The ability of ten subjects to indicate their spatial orientation in the earth-horizontal plane was tested after different rotational paths from upright to supine positions. Initial and final orientations of the subjects were the same in all cases, but the paths taken were different, and so were the angular velocities sensed by the vestibular system. The results show that seven of the ten subjects could consistently indicate their final orientation within the earth-horizontal plane. Thus perceived final orientation was independent of the path taken, i.e., the noncommutativity of rotations was taken into account.
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Reynolds, J. S., e G. T. Gdowski. "Head Movements Produced During Whole Body Rotations and Their Sensitivity to Changes in Head Inertia in Squirrel Monkeys". Journal of Neurophysiology 99, n.º 5 (maio de 2008): 2369–82. http://dx.doi.org/10.1152/jn.00320.2007.
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The head's inertia produces forces on the neck when the body moves. One collective function of the vestibulocollic and cervicocollic reflexes (VCR and CCR) is thought to be to stabilize the head with respect to the trunk during whole body movements. Little is known as to whether their head-movement kinematics produced by squirrel monkeys during whole body rotations are similar to those of cats and humans. Prior experiments with cats and human subjects have shown that yaw head-movement kinematics are unaffected by changes in the head's inertia when the whole body is rotated. These observations have led to the hypothesis that the combined actions of the VCR and CCR accommodate for changes in the head's inertia. To test this hypothesis in squirrel monkeys, it was imperative to first characterize the behavior of head movements produced during whole body rotation and then investigate their sensitivity to changes in the head's inertia. Our behavioral studies show that squirrel monkeys produce only small head movements with respect to the trunk during whole body rotations over a wide range of stimulus frequencies and velocities (0.5–4.0 Hz; 0–100°/s). Similar head movements were produced when only small additional changes in the head's inertia occurred. Electromyographic recordings from the splenius muscle revealed that an active process was utilized such that increases in muscle activation occurred when the inertia of the head was increased. These results are consistent with prior cat and human studies, suggesting that squirrel monkeys have a similar horizontal VCR and CCR.
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Huterer, Marko, e Kathleen E. Cullen. "Vestibuloocular Reflex Dynamics During High-Frequency and High-Acceleration Rotations of the Head on Body in Rhesus Monkey". Journal of Neurophysiology 88, n.º 1 (1 de julho de 2002): 13–28. http://dx.doi.org/10.1152/jn.2002.88.1.13.
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For frequencies >10 Hz, the vestibuloocular reflex (VOR) has been primarily investigated during passive rotations of the head on the body in humans. These prior studies suggest that eye movements lag head movements, as predicted by a 7-ms delay in the VOR reflex pathways. However, Minor and colleagues recently applied whole-body rotations of frequencies ≤15 Hz in monkeys and found that eye movements were nearly in phase with head motion across all frequencies. The goal of the present study was to determine whether VOR response dynamics actually differ significantly for whole-body versus head-on-body rotations. To address this question, we evaluated the gain and phase of the VOR induced by high-frequency oscillations of the head on the body in monkeys by directly measuring both head and eye movements using the magnetic search coil technique. A torque motor was used to rotate the heads of three Rhesus monkeys over the frequency range 5–25 Hz. Peak head velocity was held constant, first at ±50°/s and then ±100°/s. The VOR was found to be essentially compensatory across all frequencies; gains were near unity (1.1 at 5 Hz vs. 1.2 at 25 Hz), and phase lag increased only slightly with frequency (from 2° at 5 Hz to 11° at 25 Hz, a marked contrast to the 63° lag at 25 Hz predicted by a 7-ms VOR latency). Furthermore, VOR response dynamics were comparable in darkness and when viewing a target and did not vary with peak velocity. Although monkeys offered less resistance to the initial cycles of applied head motion, the gain and phase of the VOR did not vary for early versus late cycles, suggesting that an efference copy of the motor command to the neck musculature did not alter VOR response dynamics. In addition, VOR dynamics were also probed by applying transient head perturbations with much greater accelerations (peak acceleration >15,000°/s2) than have been previously employed. The VOR latency was between 5 and 6 ms, and mean gain was close to unity for two of the three animals tested. A simple linear model well described the VOR responses elicited by sinusoidal and transient head on body rotations. We conclude that the VOR is compensatory over a wide frequency range in monkeys and has similar response dynamics during passive rotation of the head on body as during passive rotation of the whole body in space.
Teses / dissertações sobre o assunto "Whole-body rotations"
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Navarro, Morales Deborah. "Τhe influence οf the vestibular system οn time perceptiοn". Electronic Thesis or Diss., Normandie, 2025. https://theses.hal.science/tel-05000089.
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Au niveau perceptif, le temps n’est pas une métrique constante régie par le tic-tac d’une horloge. Les distorsions temporelles surviennent en raison de divers facteurs comme le manque d’attention, les émotions, le manque de sommeil, l’excitation, le mouvement, entre autres. Cette thèse vise à explorer comment le système vestibulaire influence la perception du temps. Dans le premier axe de cette thèse deux études ont été réalisées lors des missions spatiales de longue durée. Nous avons trouvé que les astronautes à bord de la Station Spatiale Internationale estiment correctement les intervalles de temps dans l’échelle de jours, ils surestiment le temps dans les durées de secondes à minutes et sous-estiment le temps dans l’échelle des heures. Etant donné que les distorsions temporelles dans l’espace peuvent provenir de plusieurs sources, nous avons décidé de mener une tâche spécifique du système vestibulaire. Le deuxième axe comprend deux études sur la perception du temps lors de stimulations vestibulaires, en se concentrant sur les rotations corporelles. Dans la première étude, nous avons constaté que le temps perçu durant les rotations est sous-estimé par rapport aux conditions statiques chez les sujets en bonne santé. Dans la deuxième étude, nous avons confirmé que cet effet est vestibulaire, car il est absent chez les patients atteints de vestibulopathie bilatérale. Nos résultats suggèrent que la perception du temps dépend des entrées vestibulaires : lorsque ces entrées diminuent, le temps perçu est surestimé ; lorsque ces entrées augmentent (stimulées), le temps perçu est sous-estiméAt the perceptual level, time is not a constant metric defined by the ticks of a clock. Distortions in time perception occur due to various factors, including attention deficits, emotions, sleep deprivation, arousal, motion, and others. This thesis explores how the vestibular system influences time perception. In the first part of the thesis, two studies were conducted during long-term space missions. We found that astronauts aboard the International Space Station accurately estimate short time delays over days. However, they tend to overestimate durations ranging from seconds to minutes and underestimate durations on the scale of hours. Given that time distortions in space can arise from multiple sources, we conducted a specific vestibular task to isolate the vestibular contribution. The second part of the thesis includes two studies on time perception during vestibular stimulation, focusing on whole-body rotations. In the first study, we found that time during rotations is underestimated compared to static conditions in healthy subjects. In the second study, we confirmed that this time underestimation was vestibular, as it was absent in Bilateral Vestibulopathy patients. Our findings suggest that time perception depends on vestibular inputs: when vestibular inputs are decreased, perceived time is overestimated; when vestibular inputs are increased (stimulated), perceived time is underestimated
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Morgan, Lauren Jayne. "The influence of whole-body vibration and axial rotation on musculoskeletal discomfort of the neck and trunk". Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/9138.
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Elements of an individuals occupational exposure, such as their posture can affect their comfort during work, and also their long term musculoskeletal health. Knowledge as to the extent of the influence of particular aspects of the exposures can help in providing guidance on risk evaluation, and direct future technical design focus. In many situations the exposures interact, and even if the effects of individual exposures are understood, the interactions are often less so. This is certainly the case with off-road driving exposures. Specific investigations have focussed on the effects of vibration exposure, resulting in the development of international standards and guidelines on measurement and evaluation of exposure. Consideration of the posture of the operator can be accomplished through postural assessment tools, although none of the currently available methods are developed specifically for use within a vehicle environment. The issues of both the posture of the operator and the seated vibration exposure are particularly apparent in off-road agricultural driving environments, where the driving task dictates that operator is often required to maintain specific postures whilst also exposed to whole-body vibration. In agriculture, many of the tasks require the operator to maintain axially rotated postures to complete the task effectively. The analysis of the combined effects of the axial rotation of the operator and the whole-body vibration exposure has been limited to a few studies within the literature, and is currently poorly understood. The overall aim of the thesis was to assess the influence of axial rotation and whole-body vibration on the musculoskeletal discomfort of the neck and trunk, in order that the true extent of the exposure risk may be evaluated. A field study was conducted to determine the common characteristics of some typical exposures, to provide a basis for the laboratory studies. A survey of expert opinion was conducted, examining the knowledge and experience of experts in assessing the relative influence of axial rotation and whole-body vibration on operators musculoskeletal health. The main investigations of the thesis are focussed in the laboratory, where the objective and subjective effects of axial rotation (static and dynamic) and whole-body vibration were investigated. Objective measures included the investigation of muscular fatigue in response to exposures. The tasks investigated in the field study indicated that the exposures often exceed the EU Physical Agents Exposure Limit Value, and that the axial rotation is a large component of the postures required. The survey of expert opinion concluded that combined exposure to axial rotation and whole-body vibration would increase the risks of lower back pain, and that acknowledgement of combined exposures should be included when assessing for risk. The results of the laboratory studies indicated that the greatest discomfort was present when subjects were exposed to axial rotation in the neck and shoulders. Out of the 8 muscles investigated, at most 6 of the 8 indicated fatigue during an experimental exposure. The muscle group which was affected most by the exposures was the m. trapezius pars decendens. Findings demonstrated that when subjects were exposed to axial rotation and whole-body vibration they indicated discomfort and their muscles fatigued. However, there was poor correlation between the sites of discomfort and the location of muscular fatigue. The discomfort findings suggest that there is an increased risk of discomfort from experiencing axial rotation together with whole-body vibration. Investigations of muscular fatigue do not substantiate this finding.
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Lai, Szuyu, e 賴思妤. "Dynamic Visual Fitness Performing of Gymnastic Athletes during Whole Body Rotation Movement". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/11303004177225516107.
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碩士臺北巿立體育學院
運動器材研究所
100
The purpose of this study was to investigate characteristics of dynamic visual acuity (DVA) and dynamic Visual Reaction (DVR) index during whole body rotation of athletes. Twenty subjects participated in the study. Multiaxial trainer training program and Lab View program were used to collect the DVA and DVR data. These data were calculated to get the index by Vestibular ocular reflex gain. All the results showed that : (1) For the Gymnastic athletes , the range of DVA index is -3.333 to 5.263. (2) For the Gym astic athletes , the range of DVR is -0.136~0.146. (3) There is relationship between training years and dynamic visual acuity. The study is mainly focused on probing the character of athlete sensing moving vision under receiving stimuli from Vestibular. Based on the principle of study, we can pick up suitable athlete and provide more professional and efficient training for them to enable sensing moving picture, which will then be given to their coach and themselves as a reference.
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Ko, I.-Chun, e 柯毅君. "Dynamic Visual Fitness Influence of the dancers during Whole Body Rotation Movement". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/97710750872756520532.
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碩士臺北巿立體育學院
運動器材研究所
100
The purpose of this study was to investigate characteristics of dynamic visual acuity (DVA) and dynamic visual reaction (DVR) index during whole body rotation. As humans exercise, the body is affected by the vestibular and visual senses; in fast paced sports events, the sharpness of an athlete’s dynamic visual ability of motion is a deciding factor to the athlete’s overall performance. During this study, thirty-eight dancers of various styles were chosen to participate. The participants were asked to perform on the Multi-axial trainer, while a Lab View program gathers data. The dancers were tested for their DVA and DVR while performing of the vertical axis exercise, and observed for the characteristics of their dynamic visual ability. The data were then processed to get the indices by calculating the vestibular ocular reflex gain. If the DVA value is greater, it means that the DVA is better and the DVR value is smaller, it means that the DVR is better. The results showed that DVA index ranges from -3.33 to 9.09 with an average of 1.398, and DVR ranges from -0.008 to 0.674 with an average of 0.249. In the test, ballet dancers has better DVA rating than both the modern dancers and the Chinese dancers, while Chinese dancers has the best DVR rating, followed by ballet dancers, with modern dancers in the last place. Application of this experiment will allow us to pick suitable athletes and provide them with professional trainings to enhance their dynamic visual senses, which would in turn improve the performance of the dancers.
Capítulos de livros sobre o assunto "Whole-body rotations"
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Mårtensson-Pendrill, Ann-Marie. "Rotation". In Physics for the Whole Body in Playgrounds and Amusement Parks, 1–18. AIP Publishing, 2021. http://dx.doi.org/10.1063/9780735423503_004.
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D'amico M., D'amico G., Frascarello M., Paniccia M., Roncoletta P. e Vallasciani M. "A 3-D Skeleton Model & SEMG Approach For Integrated Neck And Low Back Pain Analysis Test Batteries". In Studies in Health Technology and Informatics. IOS Press, 2008. https://doi.org/10.3233/978-1-58603-888-5-79.
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Since several years our group is working on a project to merge into a full 3D reliable and detailed human skeleton representation various segmental biomechanical models presented in literature. The obtained 3D skeleton model is fully parametric and can be fitted to each subject anthropometric characteristics. A non-ionising approach based on 3D opto-electronic measurements of body landmarks labelled by passive markers has been chosen to build the 3D parametric biomechanical skeleton model. A special focus has been devoted to identify and model the spine with a correct degree of accuracy and reliability. In spine pain related pathologies is of major importance the evaluation of functional limitations associated. This requires to integrate morphological characteristics with information deriving from other measurements devices as force platform data, surface EMG, foot pressure maps. The aim of this study is to present a multi-factorial approach which integrates rachis morphological characteristics with full skeleton kinematic, dynamic and SEMG measurements to quantify spine function and mobility in particular for neck and low back pain. A set of clinical-biomechanical tests have been implemented. Static posture characteristics are first evaluated. After that, patient is asked to perform specific motion test batteries in order to fully measure the whole ROMs (spine angles ranges and spine shape modifications) for Axial rotations, forward-backward flexion-extension, lateral bendings per each spine functional units (Skull and neck, thoracic and lumbar districts). During forward bending also a digital Schober test is performed. Such data are correlated to simultaneous SEMG muscle activities recording to investigate motor co-ordination/dysfunction as well as the presence absence of flexion-relaxation phenomena associated to pain.
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Rigo M. "Pelvis Asymmetry in Idiopathic Scoliosis. Evidence of Whole Torsional Body Deformity?" In Studies in Health Technology and Informatics. IOS Press, 1997. https://doi.org/10.3233/978-1-60750-881-6-63.
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The purpose of this study was to asses the relationship between iliac rotational asymmetry and the magnitude and pattern of the lumbar curve in patients with idiopathic scoliosis. We used the bisacro-iliac-ischial angle to differenciate between IRA and intra-pelvic torsional deformity. The results of this study supports the concept that the pelvis may be involved in the pathogenesis of idiopathic scoliosis.
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Chandrasekhar, S. "The precession of the equinoxes". In Newton’s Principia for the Common Reader, 455–76. Oxford University PressOxford, 1995. http://dx.doi.org/10.1093/oso/9780198517443.003.0023.
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Abstract Lemmas I, II, and III, culminating in Proposition XXXIX ‘to find the precession of the equinoxes’ is one of those sections, interspersed throughout the Principia, in which new ideas are formulated in the context of new problems that are constantly arising. In Lemmas I, II, and III, Newton introduces, for the first time, notions that are relevant to the dynamics of rigid bodies: the moment of inertia (which determines the ‘efficacy to wheel [a body] with circular motion about a centre’); the moment of momentum (which measures the ‘motions of the whole [body] about its axis of rotation’) and the torque-’the power to wheel about’--exerted by an external force on a non-spherical body; and, indeed, the principles underlying gyroscopic motion. All these notions are defined in the context of a dynamical theory of the precession of the equinoxes which derives from the oblateness of the Earth and the inclination of its axis of rotation to the plane of the ecliptic.
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Palla, A., M. Tatalias e D. Straumann. "Hysteresis effects of the subjective visual vertical during continuous quasi-static whole-body roll rotation". In Progress in Brain Research, 271–75. Elsevier, 2008. http://dx.doi.org/10.1016/s0079-6123(08)00638-9.
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Wilson, Margaret. "Covert Imitation:How the Body Schema Acts as a Prediction Device". In Human Body Perception From The Inside Out, 211–28. Oxford University PressNew York, NY, 2005. http://dx.doi.org/10.1093/oso/9780195178371.003.0010.
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Abstract The body schema can interact with perception, cognition, and behavior in a variety of ways. In some cases, the body schema is used as a representational device in service of higher cognitive functions. Examples include covert articulation in working memory, mentally counting on one’s fingers to assist with internal calculations, and mentally rotating one’s hand or one’s whole body during a spatial reasoning task. In other cases, the body schema provides a bridge between perception and action, treating perceived objects as things to be manipulated with the body. This has been explored in the literatures on perception-for-action and the “how” system of visual processing. In still other cases, the body schema again interfaces with perception, but does something rather different with the input. Instead of planning interactive or manipulative behaviors, the body schema may encode the stimulus essentially by copying it. This may occur in particular with stimuli that, in some relevant way, match our own bodies. When we see other people sitting, standing, and moving, we are perceiving a stimulus that is isomorphic to the body that we ourselves inhabit and cause to move.
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Makikawa Masaaki, Kurata Satoshi, Higa Yoshiki, Araki Yoshiyasu e Tokue Rinzo. "Ambulatory Monitoring of Behavior in Daily Life by Accelerometers Set at Both-Near-Sides of the Joint". In Studies in Health Technology and Informatics. IOS Press, 2001. https://doi.org/10.3233/978-1-60750-928-8-840.
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In this paper we examined a new joint motion monitoring method by use of accelerometers to monitor subjects’ detailed motion in daily activities. In this method two accelerometers are set at as near points of both sides around the joint as possible. The difference between these two sensors' outputs mainly depend on the joint angle because the centrifugal and the turning acceleration occurred by the rotation around the joint can be neglected. In the experiments we tried to monitor various subject's behaviors of his upper and lower extremities and whole body motion, and could show this method is useful for the ambulatory monitoring of behavior in daily life.
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Kirby, Margaret Loewy. "Molecular Control of Looping". In Cardiac Development, 87–101. Oxford University PressNew York, NY, 2007. http://dx.doi.org/10.1093/oso/9780195178197.003.0007.
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Abstract Even though the right–left axis of the body is established during early gastrulation, cardiac looping is the first visible sign of right–left ASYMMETRY during embryonic development. In vertebrates the heart always loops to the right. Looping directionality correlates with asymmetric expression of several molecular markers, but how these molecules are translated into biomechanical forces that drive looping remains obscure. The looping process itself is important to bring the initially sequentially ordered regions of the heart tube with serial circulation into the correct conformation for chamber specification and septation to create two parallel circulations. During the looping process, the initially midline heart tube undergoes a coordinated progression of bending, rotation, and torsion (Fig. 7.1). The initial steps result in a C-shaped loop whose convexity is directed toward the right side of the body (DeHaan, 1965; Garcia-Pelaez and Arteage, 1993; Icardo, 1996; Stalsberg, 1970). The heart tube goes through two major alterations in shape to achieve the C-shaped loop: ventral bending and rightward rotation (Manner, 2000). However, because the dorsal mesocardium is still intact during C-looping (Fig. 7.1A), little movement is possible except by shape changes at the ventral midline or outer curvature which becomes the right border during C-looping. Thus, the ventral bending is actually ballooning of the newly formed ventral wall rather than bending of the whole tube. In the second part of this movement, the heart tube rotates around its craniocaudal axis, bringing the ventral midline (outer curvature) to the right and the initially left surface of the myocardial tube to form the ventral surface of the C-shaped loop (Manner, 2000). An inner curvature is formed from the dorsal midline on the left side (Fig. 7.1). This is referred to as dextral or D-looping.
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Sklavos, S., D. Anastasopoulos, N. Ziavra, M. A. Hollands e A. M. Bronstein. "Foot rotation contribution to trunk and gaze stability during whole-body mediated gaze shifts: a principal component analysis study". In Progress in Brain Research, 347–51. Elsevier, 2008. http://dx.doi.org/10.1016/s0079-6123(08)00651-1.
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"A summary of current knowledge on effects of simultaneous whole-body vibration and trunk rotation on off-road driving tasks". In Contemporary Ergonomics and Human Factors 2011, 450–60. CRC Press, 2017. http://dx.doi.org/10.1201/b11337-63.
Texto completo da fonteTrabalhos de conferências sobre o assunto "Whole-body rotations"
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Aoki, Kei, Katsuaki Kawachi, Makiko Kouchi e Masaaki Mochimaru. "Functional Joint Rotation Centers for Whole Body Digital Manikin". In Digital Human Modeling for Design and Engineering Symposium. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2008. http://dx.doi.org/10.4271/2008-01-1859.
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Druyts, Hans, Wim De Craecker, Herman Ramon, Bart Haex e Esmeralda Forausbergher. "Pelvis Rotation during Whole-Body Vibration: Modeling & amp; Validation Experiments". In 2005 Digital Human Modeling for Design and Engineering Symposium. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2005. http://dx.doi.org/10.4271/2005-01-2714.
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Gao, Mingchen, Yiqiang Zhan, Gerardo Hermosillo, Yoshihisa Shinagawa, Dimitris Metaxas e Xiang Sean Zhou. "Saliency-based rotation invariant descriptor for wrist detection in whole body CT images". In 2014 IEEE 11th International Symposium on Biomedical Imaging (ISBI 2014). IEEE, 2014. http://dx.doi.org/10.1109/isbi.2014.6867823.
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Berger, Daniel, Cengiz Terzibas, Karl Beykirch e Heinrich Bülthoff. "The Role of Visual Cues and Whole-Body Rotation in Helicopter Hovering Control". In AIAA Modeling and Simulation Technologies Conference and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2007. http://dx.doi.org/10.2514/6.2007-6798.
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Aoki, Kei, Makiko Kouchi e Masaaki Mochimaru. "Arrangement of Functional Joint Rotation Centers for the Whole Body Digital Manikin in Proportion to a Set of Body Dimensions". In Digital Human Modeling for Design and Engineering Conference and Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2009. http://dx.doi.org/10.4271/2009-01-2300.
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Abraham, P. M., e S. E. Wilson. "Effects of a Lumbar Belt on Neuromotor Transmission of Whole Body Vibration". In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-42358.
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Whole body vibration (WBV) has been identified as a risk factor for low back musculoskeletal disorders and injuries. One potential mechanism by which WBV may lead to low back injury is through stimulation of muscle spindle organs and repetitive activation of the stretch-reflex neuromotor response. Such repetitive activation could lead to muscular fatigue and/or neuromotor adaptation. Understanding mechanical transmission of vibration to the neuromotor system and the resulting neuromotor activation is critical to understanding these mechanisms. In this study, it was theorized that activation of the extensor musculature of the low back is a response to the lengthening and shortening of the extensor musculature. This lengthening and shortening of the extensor musculature may be the result of flexion-extension rotation in the lumbar spine. By measuring lumbar flexion and extension, the amplitude and phase of this lengthening and shortening were assessed. Using electromyographic data from the erector spinae muscle groups at the L2/L3 lumbar level, the cyclic activation of the extensor musculature was also measured. Neuromotor transmission was observed over a frequency range of 3–20 Hz and vibration magnitudes of 1 and 2 m/s^2 RMS. Resonance peaks in lumbar flexion-extension and the integrated electromyographic data were observed at 4 Hz and 10–12 Hz. A lumbar belt was used to reduce transmission of axial seat-pan vibration to lumbar flexion-extension and to observe the changes in cyclic electromyographic activity. The lumbar belt was found to decrease both lumbar flexion-extension and paraspinal muscle activity demonstrating a link between axial seatpan vibration, lumbar flexion-extension and the cyclic activation of the neuromotor system. These results provide information on the neuromotor effects of WBV and may be used to design better low back injury prevention methods.
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Park, Beomyeong, Myeong-Ju Kim, Eunho Sung, Junhyung Kim e Jaeheung Park. "Whole-body walking pattern using pelvis-rotation for long stride and arm swing for yaw angular momentum compensation". In 2020 IEEE-RAS 20th International Conference on Humanoid Robots (Humanoids). IEEE, 2021. http://dx.doi.org/10.1109/humanoids47582.2021.9555794.
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Bhagwan Kumbhar, Prasad, Peijun Xu e Jingzhou (James) Yang. "A Literature Survey of Biodynamic Models for Whole Body Vibration and Vehicle Ride Comfort". In ASME 2012 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/detc2012-71061.
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Vehicle ride comfort plays an important role in the vehicle design. Human body is very sensitive to whole body vibration. Vehicle ride comfort has brought lots of concerns in recent years due to requirement of better ride comfort performance for newly developed vehicles. Vehicle ride comfort has a direct effect on driver’s performance and will result in overall customer satisfaction. Various papers have reported vehicle ride comfort and various biodynamic models have been built in the literature. However, there is a lack of a comprehensive literature survey to summarize all biodynamic models for whole body vibration and vehicle ride comfort. The purpose of this paper is to have a literature review of biodynamic models. So this paper initially focuses on various health issues due to whole body vibrations. Whole body vibration transfers environmental vibration to human body through a large contact area. Vibration evaluation methods such as weighted root mean square (r.m.s.) acceleration method, fourth power VDV method are discussed. Along with that the paper will focus on various biodynamic response functions. Human models in the literature are divided into three main groups: lumped parameter (LP), finite element model (FE), and multibody model (MB). In the LP model, human body is represented by several concentrated masses which are connected by springs and dampers. The FE model considers that human body consists of numerous finite elements. And in MB model, human body is made of several rigid bodies connected by bushing element for both translational and rotational motion. So this paper thoroughly summarizes various models developed to reduce human body vibration. At the end, four different approaches of assessing ride comfort are summarized. These four approaches are ride measurement in vehicles, ride simulator test, shaker table test and subjective ride measurement.
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Seipel, Justin E. "Analytic-Holistic Two-Segment Model of Quadruped Back-Bending in the Sagittal Plane". In ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/detc2011-48853.
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Back-bending in the sagittal plane is common in many animals during legged locomotion and could be useful for robots. However, to our knowledge, there exists no analytical mechanistic model of sagittal-plane back bending legged locomotion of quadrupeds. Such a mechanistic model and knowledge derived from it is expected to enable direct analysis and insight into back bending locomotion and can be applied to the study of biomechanics or the design of robots. Here a whole-body mechanistic model is developed and governing equations of motion are derived to provide insight into the mathematical structure of the system dynamics. The model is energy conserving, consisting of massless elastic legs pinned to two body segments. The two body segments are pin-joined together with a rotational spring. The massless legs are returned to a resting angle relative to the body during swing phase. We discover: 1) Whole-body configuration variables simplify the resulting equations of motion. 2) The sagittal-plane back-bending two-segment model of legged locomotion yields stable periodic gaits.
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Georgiou, Ioannis T. "Experimental Investigation With Wireless Sensors of the Nonlinear Interaction Between Rotational Motions and Torsional Vibrations in a Coupled Rigid Rotor-Flexible Rotor System". In ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/detc2013-12813.
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This work presents an experimental study focused on a challenging signal interpretation issue arising in using wireless tri-axial sensors to measure acceleration components in rotating flexible rotor systems. Experiments with state of-the-art (modern technology microsystems) wireless accelerometers reveal that the dynamics of a rotating and-at the same time torsionally vibrating-flexible rotor system is perceived by the rotating sensor as a fast amplitude modulation of a slowly varying vibration. It is observed that the typical signal furnished by the rotating sensor consists of two distinct zones of harmonics: one is a broad band low frequency zone and is associated with the rigid body rotational motion, whereas the other zone contains distinct higher frequencies associated with torsional vibrations. The interesting result is the fact that in the frequency domain the fast torsional vibrations can be extracted sharply from the overall sensor signal. This is due to fact that the dynamics of the sensor output are characterized by slow and fast time scales. It turns out that the high harmonics of the rotating-and-vibrating system (generic motion) are very close to those of the non-rotating-but-torsionally vibrating system. A definite answer to a physics interpretation of the typical output of a rotating accelerometer (oscillator-based) is established by modeling the whole flexible rotor-sensor system as a singular perturbation coupled oscillators problem. This geometric mechanics modeling-analysis approach presents a global picture of the acceleration sensing property of stiff linear oscillators attached on rotating structures.