The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform

Tetsuya Ishikawa - One of the best experts on this subject based on the ideXlab platform.

  • Determination of the dynamic Deformation Tensor by time‐resolved triple‐crystal diffractometry
    Journal of Synchrotron Radiation, 2005
    Co-Authors: Yujiro Hayashi, Noboru Tsukuda, Eiichi Kuramoto, Yoshihito Tanaka, Tetsuya Ishikawa
    Abstract:

    : Triple-crystal X-ray diffractometry has been combined with time-resolved measurement techniques. A simple time-resolved technique was employed by using a digital storage oscilloscope and a fast X-ray detector. The time dependence of the Deformation Tensor was determined for a gallium arsenide wafer after a flash of a 130 fs laser pulse. The laser pulse produced instantaneous expansion resulting in a localized convex surface. Time-resolved measurements showed that a flexural standing wave, explained well by the classical elasticity theory for thin plates, appeared in the relaxation process.

  • Determination of the dynamic Deformation Tensor by time-resolved triple-crystal diffractometry.
    Journal of synchrotron radiation, 2005
    Co-Authors: Yujiro Hayashi, Noboru Tsukuda, Eiichi Kuramoto, Yoshihito Tanaka, Tetsuya Ishikawa
    Abstract:

    Triple-crystal X-ray diffractometry has been combined with time-resolved measurement techniques. A simple time-resolved technique was employed by using a digital storage oscilloscope and a fast X-ray detector. The time dependence of the Deformation Tensor was determined for a gallium arsenide wafer after a flash of a 130 fs laser pulse. The laser pulse produced instantaneous expansion resulting in a localized convex surface. Time-resolved measurements showed that a flexural standing wave, explained well by the classical elasticity theory for thin plates, appeared in the relaxation process.

Yujiro Hayashi - One of the best experts on this subject based on the ideXlab platform.

  • Determination of the dynamic Deformation Tensor by time‐resolved triple‐crystal diffractometry
    Journal of Synchrotron Radiation, 2005
    Co-Authors: Yujiro Hayashi, Noboru Tsukuda, Eiichi Kuramoto, Yoshihito Tanaka, Tetsuya Ishikawa
    Abstract:

    : Triple-crystal X-ray diffractometry has been combined with time-resolved measurement techniques. A simple time-resolved technique was employed by using a digital storage oscilloscope and a fast X-ray detector. The time dependence of the Deformation Tensor was determined for a gallium arsenide wafer after a flash of a 130 fs laser pulse. The laser pulse produced instantaneous expansion resulting in a localized convex surface. Time-resolved measurements showed that a flexural standing wave, explained well by the classical elasticity theory for thin plates, appeared in the relaxation process.

  • Determination of the dynamic Deformation Tensor by time-resolved triple-crystal diffractometry.
    Journal of synchrotron radiation, 2005
    Co-Authors: Yujiro Hayashi, Noboru Tsukuda, Eiichi Kuramoto, Yoshihito Tanaka, Tetsuya Ishikawa
    Abstract:

    Triple-crystal X-ray diffractometry has been combined with time-resolved measurement techniques. A simple time-resolved technique was employed by using a digital storage oscilloscope and a fast X-ray detector. The time dependence of the Deformation Tensor was determined for a gallium arsenide wafer after a flash of a 130 fs laser pulse. The laser pulse produced instantaneous expansion resulting in a localized convex surface. Time-resolved measurements showed that a flexural standing wave, explained well by the classical elasticity theory for thin plates, appeared in the relaxation process.

Colin Studholme - One of the best experts on this subject based on the ideXlab platform.

  • population based analysis of directional information in serial Deformation Tensor morphometry
    Medical Image Computing and Computer-Assisted Intervention, 2007
    Co-Authors: Colin Studholme, Valerie A Cardenas
    Abstract:

    Deformation morphometry provides a sensitive approach to detecting and mapping subtle volume changes in the brain. Population based analyses of this data have been used successfully to detect characteristic changes in different neurodegenerative conditions. However, most studies have been limited to statistical mapping of the scalar volume change at each point in the brain, by evaluating the determinant of the Jacobian of the Deformation field. In this paper we describe an approach to spatial normalisation and analysis of the full Deformation Tensor. The approach employs a spatial relocation and reorientation of Tensors of each subject. Using the assumption of small changes, we use a linear modeling of effects of clinical variables on each Deformation Tensor component across a population. We illustrate the use of this approach by examining the pattern of significance and orientation of the volume change effects in recovery from alcohol abuse. Results show new local structure which was not apparent in the analysis of scalar volume changes.

  • incorporating dti data as a constraint in Deformation Tensor morphometry between t1 mr images
    Information Processing in Medical Imaging, 2007
    Co-Authors: Colin Studholme
    Abstract:

    Deformation Tensor morphometry provides a sensitive approach to detecting and mapping subtle volume changes in the brain from conventional high resolution T1W MRI data. However, it is limited in its ability to localize volume changes within sub-regions of uniform white matter in T1W MRI. In contrast, lower resolution DTI data provides valuable complementary microstructural information within white matter. An approach to incorporating information from DTI data into Deformation Tensor morphometry of conventional high resolution T1W imaging is described. A novel mutual information (MI) derived criteria is proposed, termed diffusion paired MI, using an approximation to collective many-channel MI between all images. This approximation avoids the evaluation of high dimensional joint probability distributions, but allows a combination of conventional and diffusion data in a single registration criteria. The local gradient of this measure is used to drive a viscous fluid registration between repeated DTI-MRI imaging studies. Results on example data from clinical studies of Alzheimer's disease illustrate the improved localization of tissue loss patterns within regions of white matter.

  • MICCAI (2) - Population based analysis of directional information in serial Deformation Tensor morphometry
    Medical image computing and computer-assisted intervention : MICCAI ... International Conference on Medical Image Computing and Computer-Assisted Inte, 2007
    Co-Authors: Colin Studholme, Valerie A Cardenas
    Abstract:

    Deformation morphometry provides a sensitive approach to detecting and mapping subtle volume changes in the brain. Population based analyses of this data have been used successfully to detect characteristic changes in different neurodegenerative conditions. However, most studies have been limited to statistical mapping of the scalar volume change at each point in the brain, by evaluating the determinant of the Jacobian of the Deformation field. In this paper we describe an approach to spatial normalisation and analysis of the full Deformation Tensor. The approach employs a spatial relocation and reorientation of Tensors of each subject. Using the assumption of small changes, we use a linear modeling of effects of clinical variables on each Deformation Tensor component across a population. We illustrate the use of this approach by examining the pattern of significance and orientation of the volume change effects in recovery from alcohol abuse. Results show new local structure which was not apparent in the analysis of scalar volume changes.

  • IPMI - Incorporating DTI data as a constraint in Deformation Tensor morphometry between T1 MR Images
    Information processing in medical imaging : proceedings of the ... conference, 2007
    Co-Authors: Colin Studholme
    Abstract:

    Deformation Tensor morphometry provides a sensitive approach to detecting and mapping subtle volume changes in the brain from conventional high resolution T1W MRI data. However, it is limited in its ability to localize volume changes within sub-regions of uniform white matter in T1W MRI. In contrast, lower resolution DTI data provides valuable complementary microstructural information within white matter. An approach to incorporating information from DTI data into Deformation Tensor morphometry of conventional high resolution T1W imaging is described. A novel mutual information (MI) derived criteria is proposed, termed diffusion paired MI, using an approximation to collective many-channel MI between all images. This approximation avoids the evaluation of high dimensional joint probability distributions, but allows a combination of conventional and diffusion data in a single registration criteria. The local gradient of this measure is used to drive a viscous fluid registration between repeated DTI-MRI imaging studies. Results on example data from clinical studies of Alzheimer's disease illustrate the improved localization of tissue loss patterns within regions of white matter.

  • Deformation Tensor morphometry of semantic dementia with quantitative validation
    NeuroImage, 2004
    Co-Authors: Colin Studholme, Valerie A Cardenas, Robert S. Blumenfeld, Norbert Schuff, Howard J. Rosen, Bruce L. Miller, Michael W. Weiner
    Abstract:

    High-resolution structural MRI scans of 20 subjects diagnosed with semantic dementia were compared against scans of 20 cognitively normal control subjects using whole brain Deformation Tensor morphometry to study spatially consistent differences in local anatomical size. A fine lattice free-form volume registration algorithm was used to estimate a continuous mapping from a reference MRI to each individual subject MRI. The Jacobian of these transformations at each voxel were used to quantitatively map relative anatomical size in each individual brain. Intensity consistent filtering was applied to the determinant of these Jacobians. A careful validation using manually traced gyral anatomy was carried out and used to select an optimal Deformation Tensor filter scale at which to examine the anatomical size maps. General linear modeling at each voxel was used to decompose the influence of age and head size from the primary diagnosis. Maps of the T statistic of the diagnosis across the 40 subjects highlighted significant (P < 0.01 Bonferroni corrected) focal tissue contraction effects related to dementia diagnosis in the left temporal pole extending into the hippocampus, occipitotemporal gyrus and parahippocampal gyrus. Some evidence of greater focal contraction in gray over white matter was also apparent. Contraction effects were also seen, but with reduced significance in the right temporal anatomy, focused toward the temporal pole and hippocampal regions. Additional lower significance findings (P < 0.05 permutation corrected) were detected in the left superior frontal gyrus, left orbital gyrus and left parietal lobe.

Noboru Tsukuda - One of the best experts on this subject based on the ideXlab platform.

  • Determination of the dynamic Deformation Tensor by time‐resolved triple‐crystal diffractometry
    Journal of Synchrotron Radiation, 2005
    Co-Authors: Yujiro Hayashi, Noboru Tsukuda, Eiichi Kuramoto, Yoshihito Tanaka, Tetsuya Ishikawa
    Abstract:

    : Triple-crystal X-ray diffractometry has been combined with time-resolved measurement techniques. A simple time-resolved technique was employed by using a digital storage oscilloscope and a fast X-ray detector. The time dependence of the Deformation Tensor was determined for a gallium arsenide wafer after a flash of a 130 fs laser pulse. The laser pulse produced instantaneous expansion resulting in a localized convex surface. Time-resolved measurements showed that a flexural standing wave, explained well by the classical elasticity theory for thin plates, appeared in the relaxation process.

  • Determination of the dynamic Deformation Tensor by time-resolved triple-crystal diffractometry.
    Journal of synchrotron radiation, 2005
    Co-Authors: Yujiro Hayashi, Noboru Tsukuda, Eiichi Kuramoto, Yoshihito Tanaka, Tetsuya Ishikawa
    Abstract:

    Triple-crystal X-ray diffractometry has been combined with time-resolved measurement techniques. A simple time-resolved technique was employed by using a digital storage oscilloscope and a fast X-ray detector. The time dependence of the Deformation Tensor was determined for a gallium arsenide wafer after a flash of a 130 fs laser pulse. The laser pulse produced instantaneous expansion resulting in a localized convex surface. Time-resolved measurements showed that a flexural standing wave, explained well by the classical elasticity theory for thin plates, appeared in the relaxation process.

Eiichi Kuramoto - One of the best experts on this subject based on the ideXlab platform.

  • Determination of the dynamic Deformation Tensor by time‐resolved triple‐crystal diffractometry
    Journal of Synchrotron Radiation, 2005
    Co-Authors: Yujiro Hayashi, Noboru Tsukuda, Eiichi Kuramoto, Yoshihito Tanaka, Tetsuya Ishikawa
    Abstract:

    : Triple-crystal X-ray diffractometry has been combined with time-resolved measurement techniques. A simple time-resolved technique was employed by using a digital storage oscilloscope and a fast X-ray detector. The time dependence of the Deformation Tensor was determined for a gallium arsenide wafer after a flash of a 130 fs laser pulse. The laser pulse produced instantaneous expansion resulting in a localized convex surface. Time-resolved measurements showed that a flexural standing wave, explained well by the classical elasticity theory for thin plates, appeared in the relaxation process.

  • Determination of the dynamic Deformation Tensor by time-resolved triple-crystal diffractometry.
    Journal of synchrotron radiation, 2005
    Co-Authors: Yujiro Hayashi, Noboru Tsukuda, Eiichi Kuramoto, Yoshihito Tanaka, Tetsuya Ishikawa
    Abstract:

    Triple-crystal X-ray diffractometry has been combined with time-resolved measurement techniques. A simple time-resolved technique was employed by using a digital storage oscilloscope and a fast X-ray detector. The time dependence of the Deformation Tensor was determined for a gallium arsenide wafer after a flash of a 130 fs laser pulse. The laser pulse produced instantaneous expansion resulting in a localized convex surface. Time-resolved measurements showed that a flexural standing wave, explained well by the classical elasticity theory for thin plates, appeared in the relaxation process.