WorldWideScience

Sample records for automated simplified voxel-based

  1. Evaluation of absorbed doses in voxel-based and simplified models for small animals

    International Nuclear Information System (INIS)

    Internal dosimetry in non-human biota is desirable from the viewpoint of radiation protection of the environment. The International Commission on Radiological Protection (ICRP) proposed Reference Animals and Plants using simplified models, such as ellipsoids and spheres and calculated absorbed fractions (AFs) for whole bodies. In this study, photon and electron AFs in whole bodies of voxel-based rat and frog models have been calculated and compared with AFs in the reference models. It was found that the voxel-based and the reference frog (or rat) models can be consistent for the whole-body AFs within a discrepancy of 25 %, as the source was uniformly distributed in the whole body. The specific absorbed fractions (SAFs) and S values were also evaluated in whole bodies and all organs of the voxel-based frog and rat models as the source was distributed in the whole body or skeleton. The results demonstrated that the whole-body SAFs reflect SAFs of all individual organs as the source was uniformly distributed per mass within the whole body by about 30 % uncertainties with exceptions for body contour (up to -40 %) for both electrons and photons due to enhanced radiation leakages, and for the skeleton for photons only (up to +185 %) due to differences in the mass attenuation coefficients. For nuclides such as 90Y and 90Sr, which were concentrated in the skeleton, there were large differences between S values in the whole body and those in individual organs, however the whole-body S values for the reference models with the whole body as the source were remarkably similar to those for the voxel-based models with the skeleton as the source, within about 4 and 0.3 %, respectively. It can be stated that whole-body SAFs or S values in simplified models without internal organs are not sufficient for accurate internal dosimetry because they do not reflect SAFs or S values of all individual organs as the source was not distributed uniformly in whole body. Thus, voxel-based models

  2. Comparison of photon and electron absorbed fractions in voxel-based and simplified phantoms for small animals

    International Nuclear Information System (INIS)

    Internal dosimetry on non-human biota is getting more important from the view point of radiation protection of environment. The International Commission on Radiological Protection (ICRP) proposed the Reference Animals and Plants using simplified phantoms, such as ellipsoids and spheres, and assessed absorbed fractions (AFs) for the whole bodies. In this study, photon and electron AFs in whole body of voxel-based frog and mouse phantoms were evaluated and compared with AFs in simplified phantoms. The evaluations were done by Monte Carlo methods for voxel-based and simplified phantoms. The monoenergetic photon or electron source was considered to be distributed uniformly in whole body. There were very small differences (less than 2%) between whole-body AFs in voxel-based and simplified mouse phantoms however the differences were up to 24% for the voxel-based and the Reference Frog phantoms. Whole-body AFs in voxel-based and simplified phantoms demonstrated that not only mass but also shape of whole body effected on AFs significantly. The results of this study suggest the replacement of the Reference Animal phantoms by voxel-based animal phantoms to improve the accuracy of the whole-body AFs. (author)

  3. Fully Automated Treatment Planning for Head and Neck Radiotherapy using a Voxel-Based Dose Prediction and Dose Mimicking Method

    CERN Document Server

    McIntosh, Chris; McNiven, Andrea; Jaffray, David A; Purdie, Thomas G

    2016-01-01

    Recent works in automated radiotherapy treatment planning have used machine learning based on historical treatment plans to infer the spatial dose distribution for a novel patient directly from the planning image. We present an atlas-based approach which learns a dose prediction model for each patient (atlas) in a training database, and then learns to match novel patients to the most relevant atlases. The method creates a spatial dose objective, which specifies the desired dose-per-voxel, and therefore replaces any requirement for specifying dose-volume objectives for conveying the goals of treatment planning. A probabilistic dose distribution is inferred from the most relevant atlases, and is scalarized using a conditional random field to determine the most likely spatial distribution of dose to yield a specific dose prior (histogram) for relevant regions of interest. Voxel-based dose mimicking then converts the predicted dose distribution to a deliverable treatment plan dose distribution. In this study, we ...

  4. Voxel-Based Dose Prediction with Multi-Patient Atlas Selection for Automated Radiotherapy Treatment Planning

    CERN Document Server

    McIntosh, Chris

    2016-01-01

    Automating the radiotherapy treatment planning process is a technically challenging problem. The majority of automated approaches have focused on customizing and inferring dose volume objectives to used in plan optimization. In this work we outline a multi-patient atlas-based dose prediction approach that learns to predict the dose-per-voxel for a novel patient directly from the computed tomography (CT) planning scan without the requirement of specifying any objectives. Our method learns to automatically select the most effective atlases for a novel patient, and then map the dose from those atlases onto the novel patient. We extend our previous work to include a conditional random field for the optimization of a joint distribution prior that matches the complementary goals of an accurately spatially distributed dose distribution while still adhering to the desired dose volume histograms. The resulting distribution can then be used for inverse-planning with a new spatial dose objective, or to create typical do...

  5. Voxel-based morphometry and epilepsy.

    Science.gov (United States)

    Yasuda, Clarissa Lin; Betting, Luiz Eduardo; Cendes, Fernando

    2010-06-01

    Voxel-based morphometry is an automated technique for MRI analyses, developed to study differences in brain morphology and frequently used to study patients with diverse disorders. In epilepsy, it has been used to investigate areas with reduction or increase of gray and white matter, in different syndromes (i.e., temporal lobe epilepsy, focal cortical dysplasia and generalized epilepsies). In temporal lobe epilepsy, voxel-based morphometry showed gray/white matter atrophy extending beyond the atrophic hippocampus. These widespread abnormalities have been associated with seizure frequency, epilepsy duration, incidence of precipitating factors, cognitive dysfunction and surgical outcome. In generalized epilepsies, gray matter abnormalities were identified mainly in the thalamus and frontal cortex, reinforcing the role of the thalamocortical network in the mechanisms of generalized seizures. PMID:20518612

  6. Automated Voxel-Based Analysis of Volumetric Dynamic Contrast-Enhanced CT Data Improves Measurement of Serial Changes in Tumor Vascular Biomarkers

    International Nuclear Information System (INIS)

    Objectives: Development of perfusion imaging as a biomarker requires more robust methodologies for quantification of tumor physiology that allow assessment of volumetric tumor heterogeneity over time. This study proposes a parametric method for automatically analyzing perfused tissue from volumetric dynamic contrast-enhanced (DCE) computed tomography (CT) scans and assesses whether this 4-dimensional (4D) DCE approach is more robust and accurate than conventional, region-of-interest (ROI)-based CT methods in quantifying tumor perfusion with preliminary evaluation in metastatic brain cancer. Methods and Materials: Functional parameter reproducibility and analysis of sensitivity to imaging resolution and arterial input function were evaluated in image sets acquired from a 320-slice CT with a controlled flow phantom and patients with brain metastases, whose treatments were planned for stereotactic radiation surgery and who consented to a research ethics board-approved prospective imaging biomarker study. A voxel-based temporal dynamic analysis (TDA) methodology was used at baseline, at day 7, and at day 20 after treatment. The ability to detect changes in kinetic parameter maps in clinical data sets was investigated for both 4D TDA and conventional 2D ROI-based analysis methods. Results: A total of 7 brain metastases in 3 patients were evaluated over the 3 time points. The 4D TDA method showed improved spatial efficacy and accuracy of perfusion parameters compared to ROI-based DCE analysis (P<.005), with a reproducibility error of less than 2% when tested with DCE phantom data. Clinically, changes in transfer constant from the blood plasma into the extracellular extravascular space (Ktrans) were seen when using TDA, with substantially smaller errors than the 2D method on both day 7 post radiation surgery (±13%; P<.05) and by day 20 (±12%; P<.04). Standard methods showed a decrease in Ktrans but with large uncertainty (111.6 ± 150.5) %. Conclusions: Parametric

  7. Automated Voxel-Based Analysis of Volumetric Dynamic Contrast-Enhanced CT Data Improves Measurement of Serial Changes in Tumor Vascular Biomarkers

    Energy Technology Data Exchange (ETDEWEB)

    Coolens, Catherine, E-mail: catherine.coolens@rmp.uhn.on.ca [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario (Canada); Driscoll, Brandon [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Chung, Caroline [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Shek, Tina; Gorjizadeh, Alborz [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Ménard, Cynthia [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Jaffray, David [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario (Canada)

    2015-01-01

    Objectives: Development of perfusion imaging as a biomarker requires more robust methodologies for quantification of tumor physiology that allow assessment of volumetric tumor heterogeneity over time. This study proposes a parametric method for automatically analyzing perfused tissue from volumetric dynamic contrast-enhanced (DCE) computed tomography (CT) scans and assesses whether this 4-dimensional (4D) DCE approach is more robust and accurate than conventional, region-of-interest (ROI)-based CT methods in quantifying tumor perfusion with preliminary evaluation in metastatic brain cancer. Methods and Materials: Functional parameter reproducibility and analysis of sensitivity to imaging resolution and arterial input function were evaluated in image sets acquired from a 320-slice CT with a controlled flow phantom and patients with brain metastases, whose treatments were planned for stereotactic radiation surgery and who consented to a research ethics board-approved prospective imaging biomarker study. A voxel-based temporal dynamic analysis (TDA) methodology was used at baseline, at day 7, and at day 20 after treatment. The ability to detect changes in kinetic parameter maps in clinical data sets was investigated for both 4D TDA and conventional 2D ROI-based analysis methods. Results: A total of 7 brain metastases in 3 patients were evaluated over the 3 time points. The 4D TDA method showed improved spatial efficacy and accuracy of perfusion parameters compared to ROI-based DCE analysis (P<.005), with a reproducibility error of less than 2% when tested with DCE phantom data. Clinically, changes in transfer constant from the blood plasma into the extracellular extravascular space (K{sub trans}) were seen when using TDA, with substantially smaller errors than the 2D method on both day 7 post radiation surgery (±13%; P<.05) and by day 20 (±12%; P<.04). Standard methods showed a decrease in K{sub trans} but with large uncertainty (111.6 ± 150.5) %. Conclusions

  8. A Voxel-Based Method for Automated Identification and Morphological Parameters Estimation of Individual Street Trees from Mobile Laser Scanning Data

    Directory of Open Access Journals (Sweden)

    Hongxing Liu

    2013-01-01

    Full Text Available As an important component of urban vegetation, street trees play an important role in maintenance of environmental quality, aesthetic beauty of urban landscape, and social service for inhabitants. Acquiring accurate and up-to-date inventory information for street trees is required for urban horticultural planning, and municipal urban forest management. This paper presents a new Voxel-based Marked Neighborhood Searching (VMNS method for efficiently identifying street trees and deriving their morphological parameters from Mobile Laser Scanning (MLS point cloud data. The VMNS method consists of six technical components: voxelization, calculating values of voxels, searching and marking neighborhoods, extracting potential trees, deriving morphological parameters, and eliminating pole-like objects other than trees. The method is validated and evaluated through two case studies. The evaluation results show that the completeness and correctness of our method for street tree detection are over 98%. The derived morphological parameters, including tree height, crown diameter, diameter at breast height (DBH, and crown base height (CBH, are in a good agreement with the field measurements. Our method provides an effective tool for extracting various morphological parameters for individual street trees from MLS point cloud data.

  9. Voxel-based model construction from colored tomographic images

    International Nuclear Information System (INIS)

    This work presents a new approach in the construction of voxel-based phantoms that was implemented to simplify the segmentation process of organs and tissues reducing the time used in this procedure. The segmentation process is performed by painting tomographic images and attributing a different color for each organ or tissue. A voxel-based head and neck phantom was built using this new approach. The way as the data are stored allows an increasing in the performance of the radiation transport code. The program that calculates the radiation transport also works with image files. This capability allows image reconstruction showing isodose areas, under several points of view, increasing the information to the user. Virtual X-ray photographs can also be obtained allowing that studies could be accomplished looking for the radiographic techniques optimization assessing, at the same time, the doses in organs and tissues. The accuracy of the program here presented, called MCvoxEL, that implements this new approach, was tested by comparison to results from two modern and well-supported Monte Carlo codes. Dose conversion factors for parallel X-ray exposure were also calculated. (author)

  10. Voxel-Based LIDAR Analysis and Applications

    Science.gov (United States)

    Hagstrom, Shea T.

    One of the greatest recent changes in the field of remote sensing is the addition of high-quality Light Detection and Ranging (LIDAR) instruments. In particular, the past few decades have been greatly beneficial to these systems because of increases in data collection speed and accuracy, as well as a reduction in the costs of components. These improvements allow modern airborne instruments to resolve sub-meter details, making them ideal for a wide variety of applications. Because LIDAR uses active illumination to capture 3D information, its output is fundamentally different from other modalities. Despite this difference, LIDAR datasets are often processed using methods appropriate for 2D images and that do not take advantage of its primary virtue of 3-dimensional data. It is this problem we explore by using volumetric voxel modeling. Voxel-based analysis has been used in many applications, especially medical imaging, but rarely in traditional remote sensing. In part this is because the memory requirements are substantial when handling large areas, but with modern computing and storage this is no longer a significant impediment. Our reason for using voxels to model scenes from LIDAR data is that there are several advantages over standard triangle-based models, including better handling of overlapping surfaces and complex shapes. We show how incorporating system position information from early in the LIDAR point cloud generation process allows radiometrically-correct transmission and other novel voxel properties to be recovered. This voxelization technique is validated on simulated data using the Digital Imaging and Remote Sensing Image Generation (DIRSIG) software, a first-principles based ray-tracer developed at the Rochester Institute of Technology. Voxel-based modeling of LIDAR can be useful on its own, but we believe its primary advantage is when applied to problems where simpler surface-based 3D models conflict with the requirement of realistic geometry. To

  11. Validation of voxel-based morphometry (VBM) based on MRI

    Science.gov (United States)

    Yang, Xueyu; Chen, Kewei; Guo, Xiaojuan; Yao, Li

    2007-03-01

    Voxel-based morphometry (VBM) is an automated and objective image analysis technique for detecting differences in regional concentration or volume of brain tissue composition based on structural magnetic resonance (MR) images. VBM has been used widely to evaluate brain morphometric differences between different populations, but there isn't an evaluation system for its validation until now. In this study, a quantitative and objective evaluation system was established in order to assess VBM performance. We recruited twenty normal volunteers (10 males and 10 females, age range 20-26 years, mean age 22.6 years). Firstly, several focal lesions (hippocampus, frontal lobe, anterior cingulate, back of hippocampus, back of anterior cingulate) were simulated in selected brain regions using real MRI data. Secondly, optimized VBM was performed to detect structural differences between groups. Thirdly, one-way ANOVA and post-hoc test were used to assess the accuracy and sensitivity of VBM analysis. The results revealed that VBM was a good detective tool in majority of brain regions, even in controversial brain region such as hippocampus in VBM study. Generally speaking, much more severity of focal lesion was, better VBM performance was. However size of focal lesion had little effects on VBM analysis.

  12. Whole-brain voxel-based morphometry of white matter in medial temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Yu Aihong [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, Beijing 100053 (China); Li Kuncheng [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, Beijing 100053 (China)], E-mail: Likuncheng@vip.sina.com; Li Lin; Shan Baoci [Institute of High Energy Physics, Chinese Academy of Sciences (China); Wang Yuping; Xue Sufang [Department of Neurology, Xuanwu Hospital, Capital University of Medical Sciences (China)

    2008-01-15

    Purpose: The purpose of this study was to analyze whole-brain white matter changes in medial temporal lobe epilepsy (MTLE). Materials and methods: We studied 23 patients with MTLE and 13 age- and sex-matched healthy control subjects using voxel-based morphometry (VBM) on T1-weighted 3D datasets. The seizure focus was right sided in 11 patients and left sided in 12. The data were collected on a 1.5 T MR system and analyzed by SPM 99 to generate white matter density maps. Results: Voxel-based morphometry revealed diffusively reduced white matter in MTLE prominently including bilateral frontal lobes, bilateral temporal lobes and corpus callosum. White matter reduction was also found in the bilateral cerebellar hemispheres in the left MTLE group. Conclusion: VBM is a simple and automated approach that is able to identify diffuse whole-brain white matter reduction in MTLE.

  13. Whole-brain voxel-based morphometry of white matter in medial temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Purpose: The purpose of this study was to analyze whole-brain white matter changes in medial temporal lobe epilepsy (MTLE). Materials and methods: We studied 23 patients with MTLE and 13 age- and sex-matched healthy control subjects using voxel-based morphometry (VBM) on T1-weighted 3D datasets. The seizure focus was right sided in 11 patients and left sided in 12. The data were collected on a 1.5 T MR system and analyzed by SPM 99 to generate white matter density maps. Results: Voxel-based morphometry revealed diffusively reduced white matter in MTLE prominently including bilateral frontal lobes, bilateral temporal lobes and corpus callosum. White matter reduction was also found in the bilateral cerebellar hemispheres in the left MTLE group. Conclusion: VBM is a simple and automated approach that is able to identify diffuse whole-brain white matter reduction in MTLE

  14. Voxel-based morphometry and voxel-based diffusion tensor analysis in amyotrophic lateral sclerosis

    International Nuclear Information System (INIS)

    Objective: To evaluate gray matter volume, white matter volume and FA value changes in amyatrophic lateral sclerosis (ALS) patients by voxel-based morphometry (VBM) and voxel-based diffusion tensor analysis (VBDTA). Methods: Thirty-nine definite or probable ALS patients diagnosed by El Escorial standard and 39 healthy controls were recruited and underwent conventional MR scans and the neuropsychological evaluation. The 3D FSPGR T1WI and DTI data were collected on GE Medical 3.0 T MRI system. The 3DT1 structural images were normalized, segmented and smoothed, and then VBM analysis was performed. DTI data were acquired from 76 healthy controls, and FA map template was made. FA maps generated from the DTI data of ALS patients and healthy controls were normalized to the FA map template for voxel-based analysis. ANCOVA was applied, controlling with age and total intracranial volume for VBM and age for VBDDTA. A statistical threshold of P<0.01 (uncorrected) and cluster level of more than continuous 20 voxels determined significance. Results: Statistical results showed no significant difference in the global volumes of gray matter and white matter, total intracranial volumes and gray matter fraction between ALS patients and healthy controls, but the white matter fraction of ALS patients (0.29 ± 0.02) was significantly less than that of healthy controls (0.30 ± 0.02) statistically (P=0.003). There was significant reduction of gray matter volumes in bilateral superior frontal gyri and precentral gyri, right middle frontal gyrus, right middle and inferior temporal gyrus, left superior occipital gyrus and cuneus and left insula in ALS patients when compared with healthy controls; and the regional reduction of white matter volumes in ALS patients mainly located in genu of corpus callosum, bilateral medial frontal gyri, paracentral lobule and insula, right superior and middle frontal gyrus and left postcentral gyrus. VBDTA showed decrease in FA values in bilateral

  15. Voxel-based frog phantom for internal dose evaluation

    International Nuclear Information System (INIS)

    A voxel-based frog phantom has been developed for radiation protection of the environment. The voxel-based frog phantom was applied to evaluating self-absorbed fractions (self-AFs), which are defined as the fraction of energy emitted by a radiation source that is absorbed within the source organ. The self-AFs were evaluated for both photons and electrons in the spleen, kidneys, and liver using Monte Carlo simulations. Furthermore, self-S values (μGy/MBq·s) for 18F and 90Y in the organs were calculated using the results of the self-AFs. Consequently, the voxel-based frog phantom was found to be useful for the organ dose evaluations, which have not been proposed by the International Commission on Radiological Protection (ICRP). It was also confirmed that the self-AFs and self-S values are largely dependent on the mass of the source organ. (author)

  16. Multilevel Solvers with Aggregations for Voxel Based Analysis of Geomaterials

    OpenAIRE

    Blaheta, R. (Radim); V. Sokol

    2012-01-01

    Our motivation for voxel based analysis comes from the investigation of geomaterials (geocomposites) arising from rock grouting or sealing. We use finite element analysis based on voxel data from tomography. The arising finite element systems are large scale, which motivates the use of multilevel iterative solvers or preconditioners. Among others we concentrate on multilevel Schwarz preconditioners with aggregations. The aggregations are efficient even in the case of problems with hete...

  17. Investigation of mindfulness meditation practitioners with voxel-based morphometry

    OpenAIRE

    Hölzel, Britta K.; Ott, Ulrich; Gard, Tim; Hempel, Hannes; Weygandt, Martin; Morgen, Katrin; Vaitl, Dieter

    2008-01-01

    Mindfulness meditators practice the non-judgmental observation of the ongoing stream of internal experiences as they arise. Using voxel-based morphometry, this study investigated MRI brain images of 20 mindfulness (Vipassana) meditators (mean practice 8.6 years; 2 h daily) and compared the regional gray matter concentration to that of non-meditators matched for sex, age, education and handedness. Meditators were predicted to show greater gray matter concentration in regions that are typically...

  18. Regional gray matter abnormalities in patients with schizophrenia determined with optimized voxel-based morphometry

    Science.gov (United States)

    Guo, XiaoJuan; Yao, Li; Jin, Zhen; Chen, Kewei

    2006-03-01

    This study examined regional gray matter abnormalities across the whole brain in 19 patients with schizophrenia (12 males and 7 females), comparing with 11 normal volunteers (7 males and 4 females). The customized brain templates were created in order to improve spatial normalization and segmentation. Then automated preprocessing of magnetic resonance imaging (MRI) data was conducted using optimized voxel-based morphometry (VBM). The statistical voxel based analysis was implemented in terms of two-sample t-test model. Compared with normal controls, regional gray matter concentration in patients with schizophrenia was significantly reduced in the bilateral superior temporal gyrus, bilateral middle frontal and inferior frontal gyrus, right insula, precentral and parahippocampal areas, left thalamus and hypothalamus as well as, however, significant increases in gray matter concentration were not observed across the whole brain in the patients. This study confirms and extends some earlier findings on gray matter abnormalities in schizophrenic patients. Previous behavior and fMRI researches on schizophrenia have suggested that cognitive capacity decreased and self-conscious weakened in schizophrenic patients. These regional gray matter abnormalities determined through structural MRI with optimized VBM may be potential anatomic underpinnings of schizophrenia.

  19. Multilevel Solvers with Aggregations for Voxel Based Analysis of Geomaterials

    Czech Academy of Sciences Publication Activity Database

    Blaheta, Radim; Sokol, V.

    Berlin, Heidelberg : Springer-Verlag, 2012, -, č. 7116 /2012/, s. 489-497. ISBN 978-3-642-29842-4. ISSN 0302-9743. [LSSC 2011. Sozopol (BG), 06.06.2011-10.06.2011] R&D Projects: GA ČR GA105/09/1830 Grant ostatní: GA ČR(CZ) GD103/09/H078 Institutional research plan: CEZ:AV0Z30860518 Keywords : voxel based analysis * finite element analysis * tomography Subject RIV: IN - Informatics, Computer Science http://www.springer.com/series/558?changeHeader

  20. Comparison between effective doses for voxel-based and stylized exposure models from photon and electron irradiation

    International Nuclear Information System (INIS)

    For the last two decades, the organ and tissue equivalent dose as well as effective dose conversion coefficients recommended by the International Commission on Radiological Protection (ICRP) have been determined with exposure models based on stylized MIRD5-type phantoms representing the human body with its radiosensitive organs and tissues according to the ICRP Reference Man released in Publication No. 23, on Monte Carlo codes sometimes simulating rather simplified radiation physics and on tissue compositions from different sources. Meanwhile the International Commission on Radiation Units and Measurements (ICRU) has published reference data for human tissue compositions in Publication No. 44, and the ICRP has released a new report on anatomical reference data in Publication No. 89. As a consequence many of the components of the traditional stylized exposure models used to determine the effective dose in the past have to be replaced: Monte Carlo codes, human phantoms and tissue compositions. This paper presents results of comprehensive investigations on the dosimetric consequences to be expected from the replacement of the traditional stylized exposure models by the voxel-based exposure models. Calculations have been performed with the EGS4 Monte Carlo code for external and internal exposures to photons and electrons with the stylized, gender-specific MIRD5-type phantoms ADAM and EVA on the one hand and with the recently developed tomographic or voxel-based phantoms MAX and FAX on the other hand for a variety of exposure conditions. Ratios of effective doses for the voxel-based and the stylized exposure models will be presented for external and internal exposures to photons and electrons as a function of the energy and the geometry of the radiation field. The data indicate that for the exposure conditions considered in these investigations the effective dose may change between +60% and -50% after the replacement of the traditional exposure models by the voxel-based

  1. Comparison between effective doses for voxel-based and stylized exposure models from photon and electron irradiation

    Science.gov (United States)

    Kramer, R.; Khoury, H. J.; Vieira, J. W.

    2005-11-01

    For the last two decades, the organ and tissue equivalent dose as well as effective dose conversion coefficients recommended by the International Commission on Radiological Protection (ICRP) have been determined with exposure models based on stylized MIRD5-type phantoms representing the human body with its radiosensitive organs and tissues according to the ICRP Reference Man released in Publication No. 23, on Monte Carlo codes sometimes simulating rather simplified radiation physics and on tissue compositions from different sources. Meanwhile the International Commission on Radiation Units and Measurements (ICRU) has published reference data for human tissue compositions in Publication No. 44, and the ICRP has released a new report on anatomical reference data in Publication No. 89. As a consequence many of the components of the traditional stylized exposure models used to determine the effective dose in the past have to be replaced: Monte Carlo codes, human phantoms and tissue compositions. This paper presents results of comprehensive investigations on the dosimetric consequences to be expected from the replacement of the traditional stylized exposure models by the voxel-based exposure models. Calculations have been performed with the EGS4 Monte Carlo code for external and internal exposures to photons and electrons with the stylized, gender-specific MIRD5-type phantoms ADAM and EVA on the one hand and with the recently developed tomographic or voxel-based phantoms MAX and FAX on the other hand for a variety of exposure conditions. Ratios of effective doses for the voxel-based and the stylized exposure models will be presented for external and internal exposures to photons and electrons as a function of the energy and the geometry of the radiation field. The data indicate that for the exposure conditions considered in these investigations the effective dose may change between +60% and -50% after the replacement of the traditional exposure models by the voxel-based

  2. Finding significantly connected voxels based on histograms of connection strengths

    DEFF Research Database (Denmark)

    Kasenburg, Niklas; Pedersen, Morten; Darkner, Sune

    2016-01-01

    We explore a new approach for structural connectivity based segmentations of subcortical brain regions. Connectivity based segmentations are usually based on fibre connections from a seed region to predefined target regions. We present a method for finding significantly connected voxels based on...... the distribution of connection strengths. Paths from seed voxels to all voxels in a target region are obtained from a shortest-path tractography. For each seed voxel we approximate the distribution with a histogram of path scores. We hypothesise that the majority of estimated connections are false-positives...... and that their connection strength is distributed differently from true-positive connections. Therefore, an empirical null-distribution is defined for each target region as the average normalized histogram over all voxels in the seed region. Single histograms are then tested against the corresponding...

  3. Voxel Based Morphometry in Optical Coherence Tomography: Validation & Core Findings

    Science.gov (United States)

    Antony, Bhavna J.; Chen, Min; Carass, Aaron; Jedynak, Bruno M.; Al-Louzi, Omar; Solomon, Sharon D.; Saidha, Shiv; Calabresi, Peter A.; Prince, Jerry L.

    2016-01-01

    Optical coherence tomography (OCT) of the human retina is now becoming established as an important modality for the detection and tracking of various ocular diseases. Voxel based morphometry (VBM) is a long standing neuroimaging analysis technique that allows for the exploration of the regional differences in the brain. There has been limited work done in developing registration based methods for OCT, which has hampered the advancement of VBM analyses in OCT based population studies. Following on from our recent development of an OCT registration method, we explore the potential benefits of VBM analysis in cohorts of healthy controls (HCs) and multiple sclerosis (MS) patients. Specifically, we validate the stability of VBM analysis in two pools of HCs showing no significant difference between the two populations. Additionally, we also present a retrospective study of age and sex matched HCs and relapsing remitting MS patients, demonstrating results consistent with the reported literature while providing insight into the retinal changes associated with this MS subtype.

  4. molSimplify: A toolkit for automating discovery in inorganic chemistry.

    Science.gov (United States)

    Ioannidis, Efthymios I; Gani, Terry Z H; Kulik, Heather J

    2016-08-15

    We present an automated, open source toolkit for the first-principles screening and discovery of new inorganic molecules and intermolecular complexes. Challenges remain in the automatic generation of candidate inorganic molecule structures due to the high variability in coordination and bonding, which we overcome through a divide-and-conquer tactic that flexibly combines force-field preoptimization of organic fragments with alignment to first-principles-trained metal-ligand distances. Exploration of chemical space is enabled through random generation of ligands and intermolecular complexes from large chemical databases. We validate the generated structures with the root mean squared (RMS) gradients evaluated from density functional theory (DFT), which are around 0.02 Ha/au across a large 150 molecule test set. Comparison of molSimplify results to full optimization with the universal force field reveals that RMS DFT gradients are improved by 40%. Seamless generation of input files, preparation and execution of electronic structure calculations, and post-processing for each generated structure aids interpretation of underlying chemical and energetic trends. © 2016 Wiley Periodicals, Inc. PMID:27364957

  5. Voxel-based morphometry in patients with idiopathic generalized epilepsies.

    Science.gov (United States)

    Betting, Luiz Eduardo; Mory, Susana Barreto; Li, Li Min; Lopes-Cendes, Iscia; Guerreiro, Marilisa M; Guerreiro, Carlos A M; Cendes, Fernando

    2006-08-15

    Idiopathic generalized epilepsies (IGE) are a group of frequent age-related epilepsy syndromes. IGE are clinically characterized by generalized tonic-clonic, myoclonic and absence seizures. According to predominant seizure type and age of onset, IGE are divided in subsyndromes: childhood absence and juvenile absence epilepsy (AE), juvenile myoclonic epilepsy (JME) and generalized tonic-clonic seizures on awakening (GTCS). The limits between these subsyndromes are not well defined, supporting the existence of only one major syndrome. Visual assessment of routine magnetic resonance imaging (MRI) in patients with IGE is normal. MRI voxel-based morphometry (VBM) uses automatically segmented gray and white matter for comparisons, eliminating the investigator bias. We used VBM to study 120 individuals (47 controls, 44 with JME, 24 with AE and 15 with GTCS) to investigate the presence of subtle structural abnormalities in IGE subsyndromes. VBM was performed searching for abnormalities on gray matter concentration (GMC) between patients groups and controls. Compared to controls, JME presented increased GMC in frontobasal region and AE showed increased GMC in the superior mesiofrontal region. The GTCS group did not differ from controls. There were no areas of reduced GMC with the statistical level selected. Region of interest analysis showed increased GMC in the anterior portion of the thalamus in patients with absence seizures. Our results support subtle GMC abnormalities in patients with JME and AE when compared to controls. These findings suggest the existence of different patterns of cortical abnormalities in IGE subsyndromes. PMID:16702001

  6. Neuroanatomical voxel-based profile of schizophrenia and bipolar disorder.

    Science.gov (United States)

    Maggioni, E; Bellani, M; Altamura, A C; Brambilla, P

    2016-08-01

    Although schizophrenia (SCZ) and bipolar disorder (BD) share elements of pathology (Ellison-Wright and Bullmore, 2009), the neural mechanisms underlying these disorders are still under investigation. Up until now, many neuroimaging studies investigated the brain structural differences of SCZ and BD compared with healthy controls (HC), trying to identify the possible neuroanatomical markers for the two disorders. However, just a few studies focused on the brain structural changes between the two diagnoses. The present review summarises the findings of the voxel-based grey matter (GM) comparisons between SCZ and BD, with the objective to highlight the possible consistent anatomical differences between the two disorders. While the comparisons between patients and HC highlighted overlapping areas of GM reduction in insula and anterior cingulate cortex, the SCZ-BD comparisons suggest the presence of more generalised GM deficits in SCZ compared with BD. Indeed, in a number of studies, SCZ patients showed lower GM volumes than BD patients in fronto-temporal cortex, thalamus, hippocampus and amygdala. Conversely, only a couple of studies reported GM deficits in BD compared with SCZ, both at the level of cerebellum. In summary, the two disorders exhibit both common and specific neuroanatomical characteristics, whose knowledge is mandatory to develop innovative diagnostic and treatment strategies. PMID:27095442

  7. Voxel-based texture analysis of the brain.

    Science.gov (United States)

    Maani, Rouzbeh; Yang, Yee Hong; Kalra, Sanjay

    2015-01-01

    This paper presents a novel voxel-based method for texture analysis of brain images. Texture analysis is a powerful quantitative approach for analyzing voxel intensities and their interrelationships, but has been thus far limited to analyzing regions of interest. The proposed method provides a 3D statistical map comparing texture features on a voxel-by-voxel basis. The validity of the method was examined on artificially generated effects as well as on real MRI data in Alzheimer's Disease (AD). The artificially generated effects included hyperintense and hypointense signals added to T1-weighted brain MRIs from 30 healthy subjects. The AD dataset included 30 patients with AD and 30 age/sex matched healthy control subjects. The proposed method detected artificial effects with high accuracy and revealed statistically significant differences between the AD and control groups. This paper extends the usage of texture analysis beyond the current region of interest analysis to voxel-by-voxel 3D statistical mapping and provides a hypothesis-free analysis tool to study cerebral pathology in neurological diseases. PMID:25756621

  8. Voxel-based texture analysis of the brain.

    Directory of Open Access Journals (Sweden)

    Rouzbeh Maani

    Full Text Available This paper presents a novel voxel-based method for texture analysis of brain images. Texture analysis is a powerful quantitative approach for analyzing voxel intensities and their interrelationships, but has been thus far limited to analyzing regions of interest. The proposed method provides a 3D statistical map comparing texture features on a voxel-by-voxel basis. The validity of the method was examined on artificially generated effects as well as on real MRI data in Alzheimer's Disease (AD. The artificially generated effects included hyperintense and hypointense signals added to T1-weighted brain MRIs from 30 healthy subjects. The AD dataset included 30 patients with AD and 30 age/sex matched healthy control subjects. The proposed method detected artificial effects with high accuracy and revealed statistically significant differences between the AD and control groups. This paper extends the usage of texture analysis beyond the current region of interest analysis to voxel-by-voxel 3D statistical mapping and provides a hypothesis-free analysis tool to study cerebral pathology in neurological diseases.

  9. A voxel-based MRI morphometric study of Alzheimer's disease

    International Nuclear Information System (INIS)

    Objective: To assess the diagnostic value of voxel-based Morphometry (VBM) in studying Alzheimer's disease (AD). Methods: Graymatter density were comprehensive assessed by means of VBM on T1-weighted MRI volume sets in 19 patients with AD and 15 healthy subjects of similar age and gender ratio, 15 healthy adults. The data were collected on Siemens 1.5 T Sonata MRI systems and analyzed by SPM 99 to generate gray matter density map. Results: Relative to healthy controls, significant clusters of reduced gray matter density were found to affect medial temporal lobe ( hippocampus) (P<0.001). For hippocampus, reduced gray matter density were 1529 in the right and 1281 in the left with right-sided predominance. Moreover, atrophy of right caudate head and left medial thalamus were showed. We demonstrate global asymmetrical cortical atrophy with sparing of the sensorimotor cortex, occipital lobe and cerebellum. Conclusion: The results from VBM are in perfect agreement with those of earlier neuroimaging, which confirmed its value in demonstrating neuroanatomy of AD. VBM, the simple and automatic approach providing a full-brain assessment of AD morphology, has a good clinical perspective. (authors)

  10. Investigating structural brain changes of dehydration using voxel-based morphometry.

    Directory of Open Access Journals (Sweden)

    Daniel-Paolo Streitbürger

    Full Text Available Dehydration can affect the volume of brain structures, which might imply a confound in volumetric and morphometric studies of normal or diseased brain. Six young, healthy volunteers were repeatedly investigated using three-dimensional T(1-weighted magnetic resonance imaging during states of normal hydration, hyperhydration, and dehydration to assess volume changes in gray matter (GM, white matter (WM, and cerebrospinal fluid (CSF. The datasets were analyzed using voxel-based morphometry (VBM, a widely used voxel-wise statistical analysis tool, FreeSurfer, a fully automated volumetric segmentation measure, and SIENAr a longitudinal brain-change detection algorithm. A significant decrease of GM and WM volume associated with dehydration was found in various brain regions, most prominently, in temporal and sub-gyral parietal areas, in the left inferior orbito-frontal region, and in the extra-nuclear region. Moreover, we found consistent increases in CSF, that is, an expansion of the ventricular system affecting both lateral ventricles, the third, and the fourth ventricle. Similar degrees of shrinkage in WM volume and increase of the ventricular system have been reported in studies of mild cognitive impairment or Alzheimer's disease during disease progression. Based on these findings, a potential confound in GM and WM or ventricular volume studies due to the subjects' hydration state cannot be excluded and should be appropriately addressed in morphometric studies of the brain.

  11. Investigating structural brain changes of dehydration using voxel-based morphometry.

    Science.gov (United States)

    Streitbürger, Daniel-Paolo; Möller, Harald E; Tittgemeyer, Marc; Hund-Georgiadis, Margret; Schroeter, Matthias L; Mueller, Karsten

    2012-01-01

    Dehydration can affect the volume of brain structures, which might imply a confound in volumetric and morphometric studies of normal or diseased brain. Six young, healthy volunteers were repeatedly investigated using three-dimensional T(1)-weighted magnetic resonance imaging during states of normal hydration, hyperhydration, and dehydration to assess volume changes in gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF). The datasets were analyzed using voxel-based morphometry (VBM), a widely used voxel-wise statistical analysis tool, FreeSurfer, a fully automated volumetric segmentation measure, and SIENAr a longitudinal brain-change detection algorithm. A significant decrease of GM and WM volume associated with dehydration was found in various brain regions, most prominently, in temporal and sub-gyral parietal areas, in the left inferior orbito-frontal region, and in the extra-nuclear region. Moreover, we found consistent increases in CSF, that is, an expansion of the ventricular system affecting both lateral ventricles, the third, and the fourth ventricle. Similar degrees of shrinkage in WM volume and increase of the ventricular system have been reported in studies of mild cognitive impairment or Alzheimer's disease during disease progression. Based on these findings, a potential confound in GM and WM or ventricular volume studies due to the subjects' hydration state cannot be excluded and should be appropriately addressed in morphometric studies of the brain. PMID:22952926

  12. Diffusion tensor imaging of idiopathic normal pressure hydrocephalus. A voxel-based fractional anisotropy study

    International Nuclear Information System (INIS)

    Diffusion tensor imaging (DTI) using a 3.0 tesla magnetic resonance scanner was used to investigate white matter changes caused by idiopathic normal pressure hydrocephalus (INPH) in 10 patients diagnosed by clinical symptoms (gait disturbance, dementia, and/or urinary incontinence) and Evans index >0.3, and compared with findings for 10 age-matched controls (≥60 years). Then, using a computer-automated method, fractional anisotropy (FA) brain maps were generated and finally transformed into the standard space. Voxel-based FA values within two regions of interests (ROIs), the forceps minor and corticospinal tracts, were then separately evaluated. Within each ROI, statistical comparisons of results from the INPH and control groups were performed. In addition, for INPH patients, grading scores for clinical symptoms and FA values were correlated. The forceps minor mean FA value was much smaller for the INPH group (0.504) than for the control group (0.631). The corticospinal tract mean FA value was slightly smaller for the INPH group (0.588) than for the control group (0.632). Additional analyses indicated that lower FA values within the forceps minor tended to be associated with clinical symptoms such as urinary incontinence and gait disturbance. Our findings indicate FA values decreased in the forceps minor of INPH patients. We also found that lower values were associated with severer clinical symptoms, implying that DTI techniques may be developed for more accurate diagnosis. (author)

  13. Micromechanical analysis of nanocomposites using 3D voxel based material model

    DEFF Research Database (Denmark)

    Mishnaevsky, Leon

    2012-01-01

    A computational study on the effect of nanocomposite structures on the elastic properties is carried out with the use of the 3D voxel based model of materials and the combined Voigt–Reuss method. A hierarchical voxel based model of a material reinforced by an array of exfoliated and intercalated ...... probability of glass fibers in hybrid (hierarchical) composites, using the micromechanical voxel-based model of nanocomposites, it was observed that the nanoreinforcement in the matrix leads to slightly lower fiber failure probability....

  14. Voxel Based Morphometry Alterations in Mal de Debarquement Syndrome.

    Directory of Open Access Journals (Sweden)

    Yoon-Hee Cha

    Full Text Available Mal de debarquement syndrome (MdDS is a disorder of chronic self-motion perception that occurs though entrainment to rhythmic background motion, such as from sea voyage, and involves the perception of low-frequency rocking that can last for months or years. The neural basis of this persistent sensory perception abnormality is not well understood.We investigated grey matter volume differences underlying persistent MdDS by performing voxel-based morphometry on whole brain and pre-specified ROIs in 28 individuals with MdDS and comparing them to 18 age, sex, and handedness matched controls.MdDS participants exhibited greater grey matter volume in the left inferior parietal lobule, right inferior occipital gyrus (area V3v, right temporal pole, bilateral cerebellar hemispheric lobules VIII/IX and left lobule VIIa/VIIb. Grey matter volumes were lower in bilateral inferior frontal, orbitofrontal, pregenual anterior cingulate cortex (pgACC and left superior medial gyri (t = 3.0, p<0.005uncorr. In ROI analyses, there were no volume differences in the middle occipital gyrus (region of V5/MT or parietal operculum 2 (region of the parietoinsular vestibular cortex. Illness duration was positively related to grey matter volume in bilateral inferior frontal gyrus/anterior insula (IFG/AI, right posterior insula, superior parietal lobule, left middle occipital gyrus (V5/MT, bilateral postcentral gyrus, anterior cerebellum, and left cerebellar hemisphere and vermian lobule IX. In contrast, illness duration was negatively related to volume in pgACC, posterior middle cingulate gyrus (MCC, left middle frontal gyrus (dorsolateral prefrontal cortex-DLPFC, and right cerebellar hemispheric lobule VIIIb (t = 3.0, p<0.005uncorr. The most significant differences were decreased volume in the pgACC and increased volume in the left IFG/AI with longer illness duration (qFDRcorr <0.05. Concurrent medication use did not correlate with these findings or have a relationship with

  15. Characterization of tumor dose heterogeneity for 90Y microsphere therapies using voxel- based dosimetry

    Directory of Open Access Journals (Sweden)

    Justin Mikell

    2014-03-01

    Full Text Available Purpose: Dosimetry for 90Y microsphere therapies (YMT with Standard (SM and Partition (PM models provide only uniform dose estimates to tumor and liver. Our objective is to calculate tumor dose heterogeneity, known to effect response, using voxel-based dosimetry and investigate the limitations of SM and PM.Methods: Voxel-based dosimetry was performed on 17 YMT patients using Monte Carlo DOSXYZnrc. 90Y activity and tissue/density distributions were based on quantitative 90Y bremsstrahlung SPECT/CT. Tumors (n=31, liver, and treatment lobe/segments were segmented on diagnostic CT or MR. Dose volume histograms (DVH were created for tumors and normal liver. Bland-Altman analysis compared voxel-based mean absorbed doses to tumor and liver with SM and PM. Tumor and normal liver absorbed dose heterogeneity were investigated through metrics: integral uniformity (IU, D10/D90, COV. Correlations of heterogeneity with voxel-based mean doses and volumes were evaluated.Results: Heterogeneity metrics (mean ± 1σ for tumor dose were COV = 0.48 ± 0.28, D10/D90 = 4.7 ± 3.9, and IU = 0.8 ± 0.18. Heterogeneity metrics correlated with tumor volume (r > 0.58 but not tumor mean doses (r < 0.20. Voxel-based tumor mean doses correlated with PM (r = 0.84 but not SM (r = 0.08. Both yielded poor limits of agreement with of 83 ± 174 and -28 ± 181 Gy, respectively. Normal liver heterogeneity metrics (mean ± 1σ were COV = 0.83 ± 0.29, D10/D90 = 12 ± 15, and IU = 0.97 ± 0.03. Only D10/D90 (r = 0.49 correlated with mean normal liver absorbed dose. Voxel-based normal liver/lobe mean doses correlated with PM (r = 0.96, but had poor limits of agreement (26 ± 29 Gy.Conclusion: Tumor doses have high levels of heterogeneity that increase with volume but are independent of dose. Voxel-based DVH and dose heterogeneity metrics will promote accurate characterization of tumor response following YMT.--------------------------------------Cite this article as: Mikell J, Mourtada F

  16. Structural covariance in the hallucinating brain : a voxel-based morphometry study

    NARCIS (Netherlands)

    Modinos, Gemma; Vercammen, Ans; Mechelli, Andrea; Knegtering, Henderikus; McGuire, Philip K.; Aleman, Andre

    2009-01-01

    Background: Neuroimaging studies have indicated that a number of cortical regions express altered patterns of structural covariance in schizophrenia. The relation between these alterations and specific psychotic symptoms is yet to be investigated. We used voxel-based morphometry to examine regional

  17. Anatomical specificity of vascular endothelial growth factor expression in glioblastomas: a voxel-based mapping analysis

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Xing [Capital Medical University, Department of Neurosurgery, Beijing Tiantan Hospital, Beijing (China); Wang, Yinyan [Capital Medical University, Department of Neurosurgery, Beijing Tiantan Hospital, Beijing (China); Capital Medical University, Department of Neuropathology, Beijing Neurosurgical Institute, Beijing (China); Wang, Kai; Ma, Jun; Li, Shaowu [Capital Medical University, Department of Neuroradiology, Beijing Tiantan Hospital, Beijing (China); Liu, Shuai [Chinese Academy of Medical Sciences and Peking Union Medical College, Departments of Neurosurgery, Peking Union Medical College Hospital, Beijing (China); Liu, Yong [Chinese Academy of Sciences, Brainnetome Center, Institute of Automation, Beijing (China); Jiang, Tao [Capital Medical University, Department of Neurosurgery, Beijing Tiantan Hospital, Beijing (China); Beijing Academy of Critical Illness in Brain, Department of Clinical Oncology, Beijing (China)

    2016-01-15

    The expression of vascular endothelial growth factor (VEGF) is a common genetic alteration in malignant gliomas and contributes to the angiogenesis of tumors. This study aimed to investigate the anatomical specificity of VEGF expression levels in glioblastomas using voxel-based neuroimaging analysis. Clinical information, MR scans, and immunohistochemistry stains of 209 patients with glioblastomas were reviewed. All tumor lesions were segmented manually and subsequently registered to standard brain space. Voxel-based regression analysis was performed to correlate the brain regions of tumor involvement with the level of VEGF expression. Brain regions identified as significantly associated with high or low VEGF expression were preserved following permutation correction. High VEGF expression was detected in 123 (58.9 %) of the 209 patients. Voxel-based statistical analysis demonstrated that high VEGF expression was more likely in tumors located in the left frontal lobe and the right caudate and low VEGF expression was more likely in tumors that occurred in the posterior region of the right lateral ventricle. Voxel-based neuroimaging analysis revealed the anatomic specificity of VEGF expression in glioblastoma, which may further our understanding of genetic heterogeneity during tumor origination. This finding provides primary theoretical support for potential future application of customized antiangiogenic therapy. (orig.)

  18. Anatomical specificity of vascular endothelial growth factor expression in glioblastomas: a voxel-based mapping analysis

    International Nuclear Information System (INIS)

    The expression of vascular endothelial growth factor (VEGF) is a common genetic alteration in malignant gliomas and contributes to the angiogenesis of tumors. This study aimed to investigate the anatomical specificity of VEGF expression levels in glioblastomas using voxel-based neuroimaging analysis. Clinical information, MR scans, and immunohistochemistry stains of 209 patients with glioblastomas were reviewed. All tumor lesions were segmented manually and subsequently registered to standard brain space. Voxel-based regression analysis was performed to correlate the brain regions of tumor involvement with the level of VEGF expression. Brain regions identified as significantly associated with high or low VEGF expression were preserved following permutation correction. High VEGF expression was detected in 123 (58.9 %) of the 209 patients. Voxel-based statistical analysis demonstrated that high VEGF expression was more likely in tumors located in the left frontal lobe and the right caudate and low VEGF expression was more likely in tumors that occurred in the posterior region of the right lateral ventricle. Voxel-based neuroimaging analysis revealed the anatomic specificity of VEGF expression in glioblastoma, which may further our understanding of genetic heterogeneity during tumor origination. This finding provides primary theoretical support for potential future application of customized antiangiogenic therapy. (orig.)

  19. Whole-brain voxel-based morphometry of white matter in mild cognitive impairment

    International Nuclear Information System (INIS)

    Purpose: The purpose of this study was to analyze whole-brain white matter changes in mild cognitive impairment (MCI). Materials and methods: We studied 14 patients with MCI and 14 age- and sex-matched healthy control subjects using voxel-based morphometry (VBM) on T1-weighted 3D datasets. The data were collected on a 3T MR system and analyzed by SPM2 to generate white matter volume maps. Results: Voxel-based morphometry revealed diffusively reduced white matter in MCI prominently including the bilateral temporal gyrus, the right anterior cingulate, the bilateral superior and medial frontal gyrus and right parietal angular gyrus. White matter reduction was more prominent in anterior regions than that in posterior regions. Conclusion: Whole-brain white matter reduction in MCI patients detected with VBM has special distribution which is in line with the white matter pathology of MCI.

  20. Whole-brain voxel-based morphometry of white matter in mild cognitive impairment

    Energy Technology Data Exchange (ETDEWEB)

    Wang Zhiqun [Department of Radiology, Xuanwu Hospital of Capital Medical University, 100053, Beijing (China); Guo Xiaojuan [College of Information Science and Technology, Beijing Normal University, 100875, Beijing (China); National Key Laboratory for Cognitive Neuroscience and Learning, Beijing Normal University, 100875, Beijing (China); Qi Zhigang [Department of Radiology, Xuanwu Hospital of Capital Medical University, 100053, Beijing (China); Yao Li [College of Information Science and Technology, Beijing Normal University, 100875, Beijing (China); National Key Laboratory for Cognitive Neuroscience and Learning, Beijing Normal University, 100875, Beijing (China); Li Kuncheng, E-mail: likuncheng@xwh.ccmu.edu.c [Department of Radiology, Xuanwu Hospital of Capital Medical University, 100053, Beijing (China)

    2010-08-15

    Purpose: The purpose of this study was to analyze whole-brain white matter changes in mild cognitive impairment (MCI). Materials and methods: We studied 14 patients with MCI and 14 age- and sex-matched healthy control subjects using voxel-based morphometry (VBM) on T1-weighted 3D datasets. The data were collected on a 3T MR system and analyzed by SPM2 to generate white matter volume maps. Results: Voxel-based morphometry revealed diffusively reduced white matter in MCI prominently including the bilateral temporal gyrus, the right anterior cingulate, the bilateral superior and medial frontal gyrus and right parietal angular gyrus. White matter reduction was more prominent in anterior regions than that in posterior regions. Conclusion: Whole-brain white matter reduction in MCI patients detected with VBM has special distribution which is in line with the white matter pathology of MCI.

  1. Morphometric changes of whole brain in patients with alcohol addiction: a voxel-based morphometry study

    International Nuclear Information System (INIS)

    Objective: To evaluate morphometric changes of brain in patients with alcohol addiction by voxel-based morphometry. Methods: Fifteen patients with alcohol addiction and 15 health controls were recruited and underwent fluid attenuated inversion recovery (FLAIR) and 3D fast spoiled gradient echo (FSPGR) T1-weighted sequences on a 3.0 T MRI system. 3D FSPGR T1 structure images were normalized, segmented and smoothed, and then underwent voxel-based morphometry. An ANCOVA was applied with age, body mass index (BMI), and education years as covariates because of exact sex match. A statistical threshold of P 0.05). Conclusions: Regional gray and white matter atrophy can be the initial changes in patients with alcohol addiction and the frontal region is a relative specific damaged brain region. VBM has a potential value for the detection of subtle brain atrophy in patients with alcohol addiction. (authors)

  2. Investigating Structural Brain Changes of Dehydration Using Voxel-Based Morphometry

    OpenAIRE

    Streitbürger, Daniel-Paolo; Möller, Harald E.; Tittgemeyer, Marc; Hund-Georgiadis, Margret; Matthias L Schroeter; Mueller, Karsten

    2012-01-01

    Dehydration can affect the volume of brain structures, which might imply a confound in volumetric and morphometric studies of normal or diseased brain. Six young, healthy volunteers were repeatedly investigated using three-dimensional T 1-weighted magnetic resonance imaging during states of normal hydration, hyperhydration, and dehydration to assess volume changes in gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF). The datasets were analyzed using voxel-based morphometry (V...

  3. Correlation between voxel based morphometry and manual volumetry in magnetic resonance images of the human brain

    OpenAIRE

    Ricardo R. Uchida; Cristina M. Del-Ben; David Araújo; Geraldo Busatto-Filho; Duran, Fábio L.S.; Crippa, José A. S.; Graeff, Frederico G.

    2008-01-01

    This is a comparative study between manual volumetry (MV) and voxel based morphometry (VBM) as methods of evaluating the volume of brain structures in magnetic resonance images. The volumes of the hippocampus and the amygdala of 16 panic disorder patients and 16 healthy controls measured through MV were correlated with the volumes of gray matter estimated by optimized modulated VBM. The chosen structures are composed almost exclusively of gray matter. Using a 4 mm Gaussian filter, statistical...

  4. Diffuse Decreased Gray Matter in Patients with Idiopathic Craniocervical Dystonia: A Voxel-Based Morphometry Study

    OpenAIRE

    Piccinin, Camila C.; Luiza G. Piovesana; Santos, Maria C. A.; Rachel P. Guimarães; Campos, Brunno M.; Rezende, Thiago J. R.; Campos, Lidiane S.; Torres, Fabio R.; Amato-Filho, Augusto C.; França, Marcondes C.; Lopes-Cendes, Iscia; Cendes, Fernando; D’Abreu, Anelyssa

    2015-01-01

    Background: Recent studies have addressed the role of structures other than the basal ganglia in the pathophysiology of craniocervical dystonia (CCD). Neuroimaging studies have attempted to identify structural abnormalities in CCD but a clear pattern of alteration has not been established. We performed whole-brain evaluation using voxel-based morphometry (VBM) to identify patterns of gray matter (GM) changes in CCD. Methods: We compared 27 patients with CCD matched in age and gender to 54 ...

  5. Meditation effects within the hippocampal complex revealed by voxel-based morphometry and cytoarchitectonic probabilistic mapping

    OpenAIRE

    Luders, Eileen; Kurth, Florian; Toga, Arthur W.; Narr, Katherine L.; Gaser, Christian

    2013-01-01

    Scientific studies addressing anatomical variations in meditators' brains have emerged rapidly over the last few years, where significant links are most frequently reported with respect to gray matter (GM). To advance prior work, this study examined GM characteristics in a large sample of 100 subjects (50 meditators, 50 controls), where meditators have been practicing close to 20 years, on average. A standard, whole-brain voxel-based morphometry approach was applied and revealed significant m...

  6. Meditation effects within the hippocampal complex revealed by voxel-based morphometry and cytoarchitectonic probabilistic mapping

    OpenAIRE

    Eileen eLuders; Florian eKurth; Toga, Arthur W.; Narr, Katherine L.; Christian eGaser

    2013-01-01

    Scientific studies addressing anatomical variations in meditators’ brains have emerged rapidly over the last few years, where significant links are most frequently reported with respect to gray matter (GM). To advance prior work, this study examined GM characteristics in a large sample of 100 subjects (50 meditators, 50 controls), where meditators have been practicing close to twenty years, on average. A standard, whole-brain voxel-based morphometry approach was applied and revealed significa...

  7. The Neuroanatomical Basis of Panic Disorder and Social Phobia in Schizophrenia: A Voxel Based Morphometric Study

    OpenAIRE

    Picado Rossi, Marisol; Carmona Cañabate, Susana; Hoekzema, Elseline; Pailhez Vindual, Guillem; Bergé Baquero, Daniel; Mané, Anna; Fauquet Ars, Jordi; Hilferty, Joseph; Moreno, Ana; Cortizo, Romina; Vilarroya Oliver, Óscar; Bulbena Vilarrasa, Antonio

    2015-01-01

    Objective: It is known that there is a high prevalence of certain anxiety disorders among schizophrenic patients, especially panic disorder and social phobia. However, the neural underpinnings of the comorbidity of such anxiety disorders and schizophrenia remain unclear. Our study aims to determine the neuroanatomical basis of the co-occurrence of schizophrenia with panic disorder and social phobia. Methods: Voxel-based morphometry was used in order to examine brain structure and to measure b...

  8. The neuroanatomical basis of panic disorder and social phobia in schizophrenia: a voxel based morphometric study.

    OpenAIRE

    Picado, Marisol; Carmona, Susanna; Hoekzema, Elseline; Pailhez, Guillem; Berg?? Baquero, Daniel; Man?? Santacana, Anna; Fauquet, Jordi; Hilferty, Joseph; Moreno, Ana; Cortizo Vidal, Romina; Vilarroya, ??scar; Bulbena Vilarrasa, Antonio

    2015-01-01

    OBJECTIVE: It is known that there is a high prevalence of certain anxiety disorders among schizophrenic patients, especially panic disorder and social phobia. However, the neural underpinnings of the comorbidity of such anxiety disorders and schizophrenia remain unclear. Our study aims to determine the neuroanatomical basis of the co-occurrence of schizophrenia with panic disorder and social phobia. METHODS: Voxel-based morphometry was used in order to examine brain structure and to measure b...

  9. Brain structure in post-traumatic stress disorder: A voxel-based morphometry analysis

    OpenAIRE

    Tan, Liwen; Zhang, Li; Qi, Rongfeng; Lu, Guangming; Li, Lingjiang; Liu, Jun; Li, Weihui

    2013-01-01

    This study compared the difference in brain structure in 12 mine disaster survivors with chronic post-traumatic stress disorder, 7 cases of improved post-traumatic stress disorder symptoms, and 14 controls who experienced the same mine disaster but did not suffer post-traumatic stress disorder, using the voxel-based morphometry method. The correlation between differences in brain structure and post-traumatic stress disorder symptoms was also investigated. Results showed that the gray matter v...

  10. A Large Scale (N=400) Investigation of Gray Matter Differences in Schizophrenia Using Optimized Voxel-based Morphometry

    Science.gov (United States)

    Meda, Shashwath A.; Giuliani, Nicole R.; Calhoun, Vince D.; Jagannathan, Kanchana; Schretlen, David J.; Pulver, Anne; Cascella, Nicola; Keshavan, Matcheri; Kates, Wendy; Buchanan, Robert; Sharma, Tonmoy; Pearlson, Godfrey D.

    2008-01-01

    Background Many studies have employed voxel-based morphometry (VBM) of MRI images as an automated method of investigating cortical gray matter differences in schizophrenia. However, results from these studies vary widely, likely due to different methodological or statistical approaches. Objective To use VBM to investigate gray matter differences in schizophrenia in a sample significantly larger than any published to date, and to increase statistical power sufficiently to reveal differences missed in smaller analyses. Methods Magnetic resonance whole brain images were acquired from four geographic sites, all using the same model 1.5T scanner and software version, and combined to form a sample of 200 patients with both first episode and chronic schizophrenia and 200 healthy controls, matched for age, gender and scanner location. Gray matter concentration was assessed and compared using optimized VBM. Results Compared to the healthy controls, schizophrenia patients showed significantly less gray matter concentration in multiple cortical and subcortical regions, some previously unreported. Overall, we found lower concentrations of gray matter in regions identified in prior studies, most of which reported only subsets of the affected areas. Conclusions Gray matter differences in schizophrenia are most comprehensively elucidated using a large, diverse and representative sample. PMID:18378428

  11. Voxel-based model construction from colored tomographic images; Construcao de simuladores baseados em elementos de volume a partir de imagens tomograficas coloridas

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, Eduardo Cesar de Miranda

    2002-07-01

    This work presents a new approach in the construction of voxel-based phantoms that was implemented to simplify the segmentation process of organs and tissues reducing the time used in this procedure. The segmentation process is performed by painting tomographic images and attributing a different color for each organ or tissue. A voxel-based head and neck phantom was built using this new approach. The way as the data are stored allows an increasing in the performance of the radiation transport code. The program that calculates the radiation transport also works with image files. This capability allows image reconstruction showing isodose areas, under several points of view, increasing the information to the user. Virtual X-ray photographs can also be obtained allowing that studies could be accomplished looking for the radiographic techniques optimization assessing, at the same time, the doses in organs and tissues. The accuracy of the program here presented, called MCvoxEL, that implements this new approach, was tested by comparison to results from two modern and well-supported Monte Carlo codes. Dose conversion factors for parallel X-ray exposure were also calculated. (author)

  12. Age and gender effects on normal regional cerebral blood flow studied using two different voxel-based statistical analyses

    International Nuclear Information System (INIS)

    Fully automated analysis programs have been applied more and more to aid for the reading of regional cerebral blood flow SPECT study. They are increasingly based on the comparison of the patient study with a normal database. In this study, we evaluate the ability of Three-Dimensional Stereotactic Surface Projection (3 D-S.S.P.) to isolate effects of age and gender in a previously studied normal population. The results were also compared with those obtained using Statistical Parametric Mapping (S.P.M.99). Methods Eighty-nine 99mTc-E.C.D.-SPECT studies performed in carefully screened healthy volunteers (46 females, 43 males; age 20 - 81 years) were analysed using 3 D-S.S.P.. A multivariate analysis based on the general linear model was performed with regions as intra-subject factor, gender as inter-subject factor and age as co-variate. Results Both age and gender had a significant interaction effect with regional tracer uptake. An age-related decline (p < 0.001) was found in the anterior cingulate gyrus, left frontal association cortex and left insula. Bilateral occipital association and left primary visual cortical uptake showed a significant relative increase with age (p < 0.001). Concerning the gender effect, women showed higher uptake (p < 0.01) in the parietal and right sensorimotor cortices. An age by gender interaction (p < 0.01) was only found in the left medial frontal cortex. The results were consistent with those obtained with S.P.M.99. Conclusion 3 D-S.S.P. analysis of normal r.C.B.F. variability is consistent with the literature and other automated voxel-based techniques, which highlight the effects of both age and gender. (authors)

  13. Neuroanatomy of auditory verbal hallucinations in schizophrenia : A quantitative meta-analysis of voxel-based morphometry studies

    NARCIS (Netherlands)

    Modinos, Gemma; Costafreda, Sergi G.; van Tol, Marie-Jose; McGuire, Philip K.; Aleman, Andre; Allen, Paul

    2013-01-01

    Introduction: Voxel-based morphometry (VBM) studies demonstrate grey matter volume (GMV) deficits in schizophrenia. This method is also applied for detecting associations between specific psychotic symptoms and brain structure, such as auditory verbal hallucinations (AVHs). However, due to differing

  14. Diffuse Decreased Gray Matter in Patients with Idiopathic Craniocervical Dystonia: a Voxel-Based Morphometry Study

    Directory of Open Access Journals (Sweden)

    Camila Callegari Piccinin

    2015-01-01

    Full Text Available Background: Recent studies have addressed the role of structures other than the basal ganglia in the pathophysiology of craniocervical dystonia. Neuroimaging studies have attempted to identify structural abnormalities in craniocervical dystonia but a clear pattern of alteration has not been established. We performed whole brain evaluation using voxel-based morphometry to identify patterns of gray matter changes in craniocervical dystonia.Methods: We compared 27 patients with craniocervical dystonia matched in age and gender to 54 healthy controls. Voxel-based morphometry was used to compare gray matter volumes. We created a two-sample t-test corrected for subjects’ age and we tested with a level of significance of p<0.001 and false discovery rate correction (p<0.05. Results: Voxel-based morphometry demonstrated significant reductions of gray matter using p<0.001 in the cerebellar vermis IV/V, bilaterally in the superior frontal gyrus, precuneus, anterior cingulate and paracingulate, insular cortex, lingual gyrus and calcarine fissure; in the left hemisphere in the supplemementary motor area (SMA, inferior frontal gyrus, inferior parietal gyrus, temporal pole, supramarginal gyrus, rolandic operculum , hippocampus, middle occipital gyrus, cerebellar lobules IV/V, superior and middle temporal gyri; in the right hemisphere, the middle cingulate and precentral gyrus. Our study did not report any significant result using the false discovery rate correction. We also detected correlations between gray matter volume and age, disease duration, duration of botulinum toxin treatment and the Marsden-Fahn dystonia scale scores.Conclusions: We detected large clusters of gray matter changes chiefly in structures primarily involved in sensorimotor integration, motor planning, visuospatial function and emotional processing.

  15. A voxel-based lesion study on facial emotion recognition after penetrating brain injury

    OpenAIRE

    Dal Monte, Olga; Krueger, Frank; Solomon, Jeffrey M.; Schintu, Selene; Knutson, Kristine M.; Strenziok, Maren; Pardini, Matteo; Leopold, Anne; Raymont, Vanessa; Grafman, Jordan

    2012-01-01

    The ability to read emotions in the face of another person is an important social skill that can be impaired in subjects with traumatic brain injury (TBI). To determine the brain regions that modulate facial emotion recognition, we conducted a whole-brain analysis using a well-validated facial emotion recognition task and voxel-based lesion symptom mapping (VLSM) in a large sample of patients with focal penetrating TBIs (pTBIs). Our results revealed that individuals with pTBI performed signif...

  16. Virtual radiographies and images of homogeneous dose regions taken from human voxel-based models

    International Nuclear Information System (INIS)

    Full text: This work describes the properties of the Monte Carlo program MCvoxEL, developed in a graphic environment, that calculates absorbed dose distributions in voxel-based phantoms. The segmentation of organs and tissues is performed by painting tomographic images, and by assigning a different color to each organ or tissue of interest. Two voxel-based models (head-and-neck and chest) were built using this new approach. The way the voxels are stored in the RAM allows for a fast access of these data by the Monte Carlo code MCvoxEL. The graphical capabilities of the McvoxEL code facilitate image reconstruction with a graphical output of results, like visualized regions of absorbed fractions, specific absorbed fractions, absorbed dose per emitted particle, and absorbed dose per activity, presented under different points of view, thereby increasing the information to the user. Visualized specific absorbed fractions, virtual monoenergetic X-ray radiographs, and absorbed dose conversion coefficients for photon exposure are presented. (orig.)

  17. Spatial indices for measuring three-dimensional patterns in a voxel-based space

    Science.gov (United States)

    Jjumba, Anthony; Dragićević, Suzana

    2016-07-01

    Spatial indices are used to quantitatively describe the spatial arrangements of the features within a study region. However, most of the indices used are two-dimensional in their representation of the surface characteristics, and this is insufficient to quantify the three-dimensional properties of an area or geospatial features. With the increased availability of 3D data from laser scanning and other collection methods, a voxel-based representation of space is an important methodology that allows for an intuitive visualization of geospatial features and their analysis with 3D GIS techniques. The objective of this study is to conceptualize, develop, and implement indices that can characterize three-dimensional space and can be used to analyze the structure of spatial features in a landscape. The indices for three-dimensional space that are implemented are, namely, surface area volume, fractal dimension, lacunarity, and Moran's I which are all useful in the quantification of spatial organization found in ecological landscapes. In addition to providing the quantitative descriptors, the results indicate that a voxel-based representation provides a straightforward means of characterizing the form and composition of the spatial features using 3D indices.

  18. Towards a voxel-based geographic automata for the simulation of geospatial processes

    Science.gov (United States)

    Jjumba, Anthony; Dragićević, Suzana

    2016-07-01

    Many geographic processes evolve in a three dimensional space and time continuum. However, when they are represented with the aid of geographic information systems (GIS) or geosimulation models they are modelled in a framework of two-dimensional space with an added temporal component. The objective of this study is to propose the design and implementation of voxel-based automata as a methodological approach for representing spatial processes evolving in the four-dimensional (4D) space-time domain. Similar to geographic automata models which are developed to capture and forecast geospatial processes that change in a two-dimensional spatial framework using cells (raster geospatial data), voxel automata rely on the automata theory and use three-dimensional volumetric units (voxels). Transition rules have been developed to represent various spatial processes which range from the movement of an object in 3D to the diffusion of airborne particles and landslide simulation. In addition, the proposed 4D models demonstrate that complex processes can be readily reproduced from simple transition functions without complex methodological approaches. The voxel-based automata approach provides a unique basis to model geospatial processes in 4D for the purpose of improving representation, analysis and understanding their spatiotemporal dynamics. This study contributes to the advancement of the concepts and framework of 4D GIS.

  19. Voxel Based Representation of Full-Waveform Airborne Laser Scanner Data for Forestry Applications

    Science.gov (United States)

    Stelling, N.; Richter, K.

    2016-06-01

    The advantages of using airborne full-waveform laser scanner data in forest applications, e.g. for the description of the vertical vegetation structure or accurate biomass estimation, have been emphasized in many publications. To exploit the full potential offered by airborne full-waveform laser scanning data, the development of voxel based methods for data analysis is essential. In contrast to existing approaches based on the extraction of discrete 3D points by a Gaussian decomposition, it is very promising to derive the voxel attributes from the digitised waveform directly. For this purpose, the waveform data have to be transferred into a 3D voxel representation. This requires a series of radiometric and geometric transformations of the raw full-waveform laser scanner data. Thus, the paper deals with the geometric aspects and describes a processing chain from the raw waveform data to an attenuationcorrected volumetric forest stand reconstruction. The integration of attenuation-corrected waveform data into the voxel space is realised with an efficient parametric voxel traversal method operating on an octree data structure. The voxel attributes are derived from the amplitudes of the attenuation-corrected waveforms. Additionally, a new 3D filtering approach is presented to eliminate non-object voxel. Applying these methods to real full-waveform laser scanning data, a voxel based representation of a spruce was generated combining three flight strips from different viewing directions.

  20. Brain structure in diving players on MR imaging studied with voxel-based morphometry

    Institute of Scientific and Technical Information of China (English)

    Gaoxia Wei; Jing Luo; Youfa Li

    2009-01-01

    We adopted professional diving players as a typical subject pool to explore whether structural brain differences relative to motor skill acquisition exist between highly skilled athletes and non-athletes. Based on the voxel-based morphometric (VBM) technique, structural MRIs of the brains of 12 elite diving players with professional training were analyzed and compared with those of control subjects with-out any professional physical training. Diving players showed significantly increased gray matter density in the thalamus and left pre-central gyrus than control subjects. However, future researches are needed to prove the contribution of preposition and practice. It also suggests that athletes as the subject pool could form a new subject pool to explore plastic change induced by motor skill acquisition.

  1. Shifting from region of interest (ROI) to voxel-based analysis in human brain mapping

    International Nuclear Information System (INIS)

    Current clinical studies involve multidimensional high-resolution images containing an overwhelming amount of structural and functional information. The analysis of such a wealth of information is becoming increasingly difficult yet necessary in order to improve diagnosis, treatment and healthcare. Voxel-wise analysis is a class of modern methods of image processing in the medical field with increased popularity. It has replaced manual region of interest (ROI) analysis and has provided tools to make statistical inferences at voxel level. The introduction of voxel-based analysis software in all modern commercial scanners allows clinical use of these techniques. This review will explain the main principles, advantages and disadvantages behind these methods of image analysis. (orig.)

  2. A voxel-based finite element model for the prediction of bladder deformation

    International Nuclear Information System (INIS)

    Purpose: A finite element (FE) bladder model was previously developed to predict bladder deformation caused by bladder filling change. However, two factors prevent a wide application of FE models: (1) the labor required to construct a FE model with high quality mesh and (2) long computation time needed to construct the FE model and solve the FE equations. In this work, we address these issues by constructing a low-resolution voxel-based FE bladder model directly from the binary segmentation images and compare the accuracy and computational efficiency of the voxel-based model used to simulate bladder deformation with those of a classical FE model with a tetrahedral mesh. Methods: For ten healthy volunteers, a series of MRI scans of the pelvic region was recorded at regular intervals of 10 min over 1 h. For this series of scans, the bladder volume gradually increased while rectal volume remained constant. All pelvic structures were defined from a reference image for each volunteer, including bladder wall, small bowel, prostate (male), uterus (female), rectum, pelvic bone, spine, and the rest of the body. Four separate FE models were constructed from these structures: one with a tetrahedral mesh (used in previous study), one with a uniform hexahedral mesh, one with a nonuniform hexahedral mesh, and one with a low-resolution nonuniform hexahedral mesh. Appropriate material properties were assigned to all structures and uniform pressure was applied to the inner bladder wall to simulate bladder deformation from urine inflow. Performance of the hexahedral meshes was evaluated against the performance of the standard tetrahedral mesh by comparing the accuracy of bladder shape prediction and computational efficiency. Results: FE model with a hexahedral mesh can be quickly and automatically constructed. No substantial differences were observed between the simulation results of the tetrahedral mesh and hexahedral meshes (<1% difference in mean dice similarity coefficient to

  3. Treatment plan modification using voxel-based weighting factors/dose prescription

    International Nuclear Information System (INIS)

    Under various clinical situations, it is desirable to modify the original treatment plan to better suit the clinical goals. In this work, a method to help physicians modify treatment plans based on their clinical preferences is proposed. The method uses a weighted quadratic dose objective function. The commonly used organ-/ROI-based weighting factors are expanded to a set of voxel-based weighting factors in order to obtain greater flexibility in treatment plan modification. Two different but equivalent modification schemes based on Rustem's quadratic programming algorithms -modification of a weighting matrix and modification of prescribed doses - are presented. Case studies demonstrated the effectiveness of the two methods with regard to their capability to fine-tune treatment plans

  4. Gray matter abnormalities in Internet addiction: A voxel-based morphometry study

    International Nuclear Information System (INIS)

    Background: This study aims to investigate brain gray matter density (GMD) changes in adolescents with Internet addiction (IA) using voxel-based morphometry (VBM) analysis on high-resolution T1-weighted structural magnetic resonance images. Methods: Eighteen IA adolescents and 15 age- and gender-matched healthy controls took part in this study. High-resolution T1-weighted magnetic resonance imaging scans were performed on the two groups. VBM analysis was used to compare the GMD between the two groups. Results: Compared with healthy controls, IA adolescents had lower GMD in the left anterior cingulate cortex, left posterior cingulate cortex, left insula, and left lingual gyrus. Conclusions: Our findings suggested that brain structural changes were present in IA adolescents, and this finding may provide a new insight into the pathogenesis of IA.

  5. Voxel based morphometry in optical coherence tomography: validation and core findings

    Science.gov (United States)

    Antony, Bhavna J.; Chen, Min; Carass, Aaron; Jedynak, Bruno M.; Al-Louzi, Omar; Solomon, Sharon D.; Saidha, Shiv; Calabresi, Peter A.; Prince, Jerry L.

    2016-03-01

    Optical coherence tomography (OCT) of the human retina is now becoming established as an important modality for the detection and tracking of various ocular diseases. Voxel based morphometry (VBM) is a long standing neuroimaging analysis technique that allows for the exploration of the regional differences in the brain. There has been limited work done in developing registration based methods for OCT, which has hampered the advancement of VBM analyses in OCT based population studies. Following on from our recent development of an OCT registration method, we explore the potential benefits of VBM analysis in cohorts of healthy controls (HCs) and multiple sclerosis (MS) patients. Specifically, we validate the stability of VBM analysis in two pools of HCs showing no significant difference between the two populations. Additionally, we also present a retrospective study of age and sex matched HCs and relapsing remitting MS patients, demonstrating results consistent with the reported literature while providing insight into the retinal changes associated with this MS subtype.

  6. Gray matter abnormalities in Internet addiction: A voxel-based morphometry study

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Yan, E-mail: clare1475@hotmail.com [Department of Radiology, RenJi Hospital, Jiao Tong University Medical School, Shanghai 200127 (China); Lin Fuchun, E-mail: fclin@wipm.ac.cn [State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Du Yasong, E-mail: yasongdu@yahoo.com.cn [Department of Child and Adolescent Psychiatry Shanghai Mental Health Center, Shanghai Jiao Tong University, Shanghai 200030 (China); Qin Lingdi, E-mail: flyingfool838@hotmail.com [Department of Radiology, RenJi Hospital, Jiao Tong University Medical School, Shanghai 200127 (China); Zhao Zhimin, E-mail: zmzsky@163.com [Department of Child and Adolescent Psychiatry Shanghai Mental Health Center, Shanghai Jiao Tong University, Shanghai 200030 (China); Xu Jianrong, E-mail: xujianr@hotmail.com [Department of Radiology, RenJi Hospital, Jiao Tong University Medical School, Shanghai 200127 (China); Lei Hao, E-mail: leihao@wipm.ac.cn [State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China)

    2011-07-15

    Background: This study aims to investigate brain gray matter density (GMD) changes in adolescents with Internet addiction (IA) using voxel-based morphometry (VBM) analysis on high-resolution T1-weighted structural magnetic resonance images. Methods: Eighteen IA adolescents and 15 age- and gender-matched healthy controls took part in this study. High-resolution T1-weighted magnetic resonance imaging scans were performed on the two groups. VBM analysis was used to compare the GMD between the two groups. Results: Compared with healthy controls, IA adolescents had lower GMD in the left anterior cingulate cortex, left posterior cingulate cortex, left insula, and left lingual gyrus. Conclusions: Our findings suggested that brain structural changes were present in IA adolescents, and this finding may provide a new insight into the pathogenesis of IA.

  7. The relationship between trait positive empathy and brain structure: a voxel-based morphometry study.

    Science.gov (United States)

    Yue, Tong; Pan, Weigang; Huang, Xiting

    2016-04-13

    Although studies relating to positive empathy have received increased attention in recent years, no studies have been carried out to explore the neural basis of positive empathy. Using a voxel-based morphometry analysis, this study investigates the relationship between trait positive empathy (as measured by the Positive Empathy Scale) and its association with brain structure in 86 healthy college students. The results indicate that an individual's ability to show positive empathy is positively correlated with the volume of gray matter in the right insula, left anterior cingulate cortex, dorsolateral prefrontal cortex, and medial prefrontal cortex. It may be suggested that the differences between the abilities of emotion processing and regulating play important roles in shaping an individual's positive empathy traits from the perspective of brain morphometry. PMID:26963166

  8. A voxel-based mouse for internal dose calculations using Monte Carlo simulations (MCNP)

    International Nuclear Information System (INIS)

    Murine models are useful for targeted radiotherapy pre-clinical experiments. These models can help to assess the potential interest of new radiopharmaceuticals. In this study, we developed a voxel-based mouse for dosimetric estimates. A female nude mouse (30 g) was frozen and cut into slices. High-resolution digital photographs were taken directly on the frozen block after each section. Images were segmented manually. Monoenergetic photon or electron sources were simulated using the MCNP4c2 Monte Carlo code for each source organ, in order to give tables of S-factors (in Gy Bq sup - sup 1 s sup - sup 1) for all target organs. Results obtained from monoenergetic particles were then used to generate S-factors for several radionuclides of potential interest in targeted radiotherapy. Thirteen source and 25 target regions were considered in this study. For each source region, 16 photon and 16 electron energies were simulated. Absorbed fractions, specific absorbed fractions and S-factors were calculated for 16 radionuclides of interest for targeted radiotherapy. The results obtained generally agree well with data published previously. For electron energies ranging from 0.1 to 2.5 MeV, the self-absorbed fraction varies from 0.98 to 0.376 for the liver, and from 0.89 to 0.04 for the thyroid. Electrons cannot be considered as 'non-penetrating' radiation for energies above 0.5 MeV for mouse organs. This observation can be generalized to radionuclides: for example, the beta self-absorbed fraction for the thyroid was 0.616 for I-131; absorbed fractions for Y-90 for left kidney-to-left kidney and for left kidney-to-spleen were 0.486 and 0.058, respectively. Our voxel-based mouse allowed us to generate a dosimetric database for use in preclinical targeted radiotherapy experiments. (author)

  9. Simplified Automated Image Analysis for Detection and Phenotyping of Mycobacterium tuberculosis on Porous Supports by Monitoring Growing Microcolonies

    OpenAIRE

    den Hertog, Alice L.; Dennis W Visser; Ingham, Colin J.; Frank H A G Fey; Paul R Klatser; Anthony, Richard M.

    2010-01-01

    BACKGROUND: Even with the advent of nucleic acid (NA) amplification technologies the culture of mycobacteria for diagnostic and other applications remains of critical importance. Notably microscopic observed drug susceptibility testing (MODS), as opposed to traditional culture on solid media or automated liquid culture, has shown potential to both speed up and increase the provision of mycobacterial culture in high burden settings. METHODS: Here we explore the growth of Mycobacterial tubercul...

  10. The Neural Basis of Reversible Sentence Comprehension: Evidence from Voxel-Based Lesion Symptom Mapping in Aphasia

    Science.gov (United States)

    Thothathiri, Malathi; Kimberg, Daniel Y.; Schwartz, Myrna F.

    2012-01-01

    We explored the neural basis of reversible sentence comprehension in a large group of aphasic patients (n = 79). Voxel-based lesion symptom mapping revealed a significant association between damage in temporo-parietal cortex and impaired sentence comprehension. This association remained after we controlled for phonological working memory. We…

  11. Dyslexia and Voxel-Based Morphometry: Correlations between Five Behavioural Measures of Dyslexia and Gray and White Matter Volumes

    Science.gov (United States)

    Tamboer, Peter; Scholte, H. Steven; Vorst, Harrie C. M.

    2015-01-01

    In voxel-based morphometry studies of dyslexia, the relation between causal theories of dyslexia and gray matter (GM) and white matter (WM) volume alterations is still under debate. Some alterations are consistently reported, but others failed to reach significance. We investigated GM alterations in a large sample of Dutch students (37 dyslexics…

  12. Accelerated cerebral white matter development in preterm infants: a voxel-based morphometry study with diffusion tensor MR imaging

    DEFF Research Database (Denmark)

    Giménez, Mónica; Born, A Peter; Nagy, Zoltan;

    2008-01-01

    Twenty-seven preterm infants were compared to 10 full-term infants at term equivalent age using a voxel-based analysis of diffusion tensor imaging of the brain. Preterm infants exhibited higher fractional anisotropy values, which may suggest accelerated maturation, in the location of the sagittal...

  13. Dyslexia and voxel-based morphometry: correlations between five behavioural measures of dyslexia and gray and white matter volumes

    NARCIS (Netherlands)

    P. Tamboer; H.S. Scholte; H.C.M. Vorst

    2015-01-01

    In voxel-based morphometry studies of dyslexia, the relation between causal theories of dyslexia and gray matter (GM) and white matter (WM) volume alterations is still under debate. Some alterations are consistently reported, but others failed to reach significance. We investigated GM alterations in

  14. A voxel-based multiscale model to simulate the radiation response of hypoxic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Espinoza, I., E-mail: iespinoza@fis.puc.cl [Institute of Physics, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile and Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg 69120 (Germany); Peschke, P. [Clinical Cooperation Unit Molecular Radiooncology, German Cancer Research Center (DKFZ), Heidelberg 69120 (Germany); Karger, C. P. [Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg 69120 (Germany)

    2015-01-15

    Purpose: In radiotherapy, it is important to predict the response of tumors to irradiation prior to the treatment. This is especially important for hypoxic tumors, which are known to be highly radioresistant. Mathematical modeling based on the dose distribution, biological parameters, and medical images may help to improve this prediction and to optimize the treatment plan. Methods: A voxel-based multiscale tumor response model for simulating the radiation response of hypoxic tumors was developed. It considers viable and dead tumor cells, capillary and normal cells, as well as the most relevant biological processes such as (i) proliferation of tumor cells, (ii) hypoxia-induced angiogenesis, (iii) spatial exchange of cells leading to tumor growth, (iv) oxygen-dependent cell survival after irradiation, (v) resorption of dead cells, and (vi) spatial exchange of cells leading to tumor shrinkage. Oxygenation is described on a microscopic scale using a previously published tumor oxygenation model, which calculates the oxygen distribution for each voxel using the vascular fraction as the most important input parameter. To demonstrate the capabilities of the model, the dependence of the oxygen distribution on tumor growth and radiation-induced shrinkage is investigated. In addition, the impact of three different reoxygenation processes is compared and tumor control probability (TCP) curves for a squamous cells carcinoma of the head and neck (HNSSC) are simulated under normoxic and hypoxic conditions. Results: The model describes the spatiotemporal behavior of the tumor on three different scales: (i) on the macroscopic scale, it describes tumor growth and shrinkage during radiation treatment, (ii) on a mesoscopic scale, it provides the cell density and vascular fraction for each voxel, and (iii) on the microscopic scale, the oxygen distribution may be obtained in terms of oxygen histograms. With increasing tumor size, the simulated tumors develop a hypoxic core. Within the

  15. Mapping the brain in type II diabetes: Voxel-based morphometry using DARTEL

    International Nuclear Information System (INIS)

    Purpose: To investigate the pattern of brain volume changes of the brain in patients with type II diabetes mellitus using voxel-based morphometry. Material and methods: Institutional ethics approval and informed consent were obtained. VBM based on the high resolution three-dimensional T1-weighted fast spoiled gradient recalled echo MRI images was obtained from 16 type II diabetes patients (mean age 61.2 years) and 16 normal controls (mean age 59.6 years). All images were spatially preprocessed using Diffeomorphic Anatomical Registration using Exponentiated Lie algebra (DARTEL) algorithm, and the DARTEL templates were made from 100 normal subjects. Statistical parametric mapping was generated using analysis of covariance (ANCOVA). Results: An atrophy pattern of gray matter was seen in type II diabetes patients compared with controls that involved the right superior, middle, and inferior temporal gyri, right precentral gyrus, and left rolandic operculum region. The loss of white matter volume in type II diabetes mellitus was observed in right temporal lobe and left inferior frontal triangle region. ROI analysis revealed that the gray and white matter volume of right temporal lobe were significant lower in type II diabetes mellitus than that in controls (P < 0.05). Conclusion: This work demonstrated that type II diabetes mellitus patients mainly exhibited gray and white matter atrophy in right temporal lobe, and this finding supported that type II diabetes mellitus could lead to subtle diabetic brain structural changes in patients without dementia or macrovascular complications.

  16. Structural Brain Abnormalities in Juvenile Myoclonic Epilepsy Patients: Volumetry and Voxel-Based Morphometry

    International Nuclear Information System (INIS)

    We aimed to find structural brain abnormalities in juvenile myoclonic epilepsy (JME) patients. The volumes of the cerebrum, hippocampus and frontal lobe and the area of the corpus callosum's subdivisions were all semiautomatically measured, and then optimized voxel-based morphometry (VBM) was performed in 19 JME patients and 19 age/gender matched normal controls. The rostrum and rostral body of the corpus callosum and the left hippocampus were significantly smaller than those of the normal controls, whereas the volume of the JME's left frontal lobe was significantly larger than that of the controls. The area of the rostral body had a significant positive correlation with the age of seizure onset (r=0.56, p=0.012), and the volume of the right frontal lobe had a significant negative correlation with the duration of disease (r=-0.51, p=0.025). On the VBM, the gray matter concentration of the prefrontal lobe (bilateral gyri rectus, anterior orbital gyri, left anterior middle frontal gyrus and right anterior superior frontal gyrus) was decreased in the JME group (corrected p<0.05). The JME patients showed complex structural abnormalities in the corpus callosum, frontal lobe and hippocampus, and also a decreased gray matter concentration of the prefrontal region, which all suggests there is an abnormal neural network in the JME brain

  17. Voxel-based morphometry in the parkinson variant of multiple system atrophy

    International Nuclear Information System (INIS)

    Objective: To assess patterns of the gray and white matter atrophy in patients with multiple system atrophy-P (MSA-P) variant of whole brain compared with normal controls. Methods: Three dimensional fast spoiled gradient echo (3D-FSPGR) T1WI of whole brain were obtained from 13 patients with probable MSA-P and 14 age-matched normal controls. The volume of gray matter (GM) and white matter (WM) of MSA-P patients and normal controls was analyzed with voxel-based morphometry (VBM) using statistical parametric mapping (SPM) 8. Results: Compared with the controls, the MSA-P patients showed decreased gray matter and white matter in broad areas. Gray matter loss mainly symmetrically distributed in bilateral supplementary motor area (SMA), dorsal posterior cingulate cortex (DPCC), medial frontal gyrus, superior temporal gyrus, cerebellum cortex, eta Unilateral involvement of cortices mainly located in right primary motor cortex, somatosensory association cortex (SAC), and left ventral anterior cingulate cortex (VACC). There was white matter loss in bilateral superior frontal gyrus, bilateral precuneus, bilateral sub-gyrus of frontal lobe, left superior temporal gyrus, left cingulate gyrus, right orbitofrontal area, right sub- gyrus of temporal lobe, etc. Conclusion: VBM method is an automatic and comprehensive volumetry method and can objectively detect the difference of the whole brain structure in patients with probable MSA- P comparing with normal controls. (authors)

  18. Grey matter abnormalities in untreated hyperthyroidism: A voxel-based morphometry study using the DARTEL approach

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei, E-mail: will.zhang.1111@gmail.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Department of Radiology, Sichuan Provincial Corps Hospital, Chinese People' s Armed Police Forces, Leshan 614000 (China); Song, Lingheng, E-mail: songlh1023@hotmail.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Department of Radiology, No. 324 Hospital of PLA, Chongqing 400020 (China); Yin, Xuntao, E-mail: xuntaoyin@gmail.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Zhang, Jiuquan, E-mail: jiuquanzhang@yahoo.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Liu, Chen, E-mail: cqliuchen@foxmail.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Wang, Jian, E-mail: wangjian_811@yahoo.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Zhou, Daiquan, E-mail: zhoudq77@sina.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Chen, Bing, E-mail: chenbing3@medmail.com.cn [Department of Endocrinology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Lii, Haitao, E-mail: haitaolii023@gmail.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China)

    2014-01-15

    Objective: Hyperthyroidism is frequently associated with pronounced neuropsychiatric symptoms such as impulsiveness, irritability, poor concentration, and memory impairments. Functional neuroimaging has revealed changes in cerebral metabolism in hyperthyroidism, but regional changes in cortical morphology associated with specific neurological deficits have not been studied so far. To investigate the pathophysiology underlying hyperthyroid-associated neural dysfunction, we compared grey matter volume (GMV) between adult hyperthyroid patients and matched healthy controls using voxel-based morphometry (VBM). Materials and methods: High resolution 3D T1-weighted images were acquired by 3T MRI from 51 hyperthyroid patients and 51 controls. VBM analysis was performed using SPM8. Correlations between regional GMV and both serum free thyroid hormone (TH) concentrations and disease duration were assessed by multiple regression analysis. Results: Compared to controls, GM volumes in the bilateral hippocampus, parahippocampal gyrus, calcarine, lingual gyrus, and left temporal pole were lower and bilateral supplementary motor area GMV higher in hyperthyroid patients. Serum free triiodothyronine (FT3) concentration was negatively correlated with the normalized regional volume (NRV) of the left parahippocampal gyrus and serum free thyroxine (FT4) concentration negatively correlated with the NRV of the left hippocampus and right parahippocampal gyrus. Disease duration was negatively correlated with the NRV of the left hippocampus, bilateral parahippocampal gyrus, and left temporal pole. Conclusion: Hyperthyroid patients exhibited reduced GMV in regions associated with memory, attention, emotion, vision, and motor planning. Negative correlations between GMV and both free TH and disease duration suggest that chronic TH elevation induces abnormalities in the adult cortex.

  19. Mapping the brain in type II diabetes: Voxel-based morphometry using DARTEL

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhiye [Department of Radiology, PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Li, Lin [Department of Geriatric Endocrinology, PLA General Hospital, Beijing 100853 (China); Sun, Jie [Department of Endocrinology, PLA General Hospital, Beijing 100853 (China); Ma, Lin, E-mail: cjr.malin@vip.163.com [Department of Radiology, PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China)

    2012-08-15

    Purpose: To investigate the pattern of brain volume changes of the brain in patients with type II diabetes mellitus using voxel-based morphometry. Material and methods: Institutional ethics approval and informed consent were obtained. VBM based on the high resolution three-dimensional T1-weighted fast spoiled gradient recalled echo MRI images was obtained from 16 type II diabetes patients (mean age 61.2 years) and 16 normal controls (mean age 59.6 years). All images were spatially preprocessed using Diffeomorphic Anatomical Registration using Exponentiated Lie algebra (DARTEL) algorithm, and the DARTEL templates were made from 100 normal subjects. Statistical parametric mapping was generated using analysis of covariance (ANCOVA). Results: An atrophy pattern of gray matter was seen in type II diabetes patients compared with controls that involved the right superior, middle, and inferior temporal gyri, right precentral gyrus, and left rolandic operculum region. The loss of white matter volume in type II diabetes mellitus was observed in right temporal lobe and left inferior frontal triangle region. ROI analysis revealed that the gray and white matter volume of right temporal lobe were significant lower in type II diabetes mellitus than that in controls (P < 0.05). Conclusion: This work demonstrated that type II diabetes mellitus patients mainly exhibited gray and white matter atrophy in right temporal lobe, and this finding supported that type II diabetes mellitus could lead to subtle diabetic brain structural changes in patients without dementia or macrovascular complications.

  20. Influence of regional cerebral blood volume on voxel-based morphometry.

    Science.gov (United States)

    Zheng, Lei; Cleppien, Dirk; Gass, Natalia; Falfan-Melgoza, Claudia; Vollmayr, Barbara; Hesser, Jürgen; Weber-Fahr, Wolfgang; Sartorius, Alexander

    2016-06-01

    The investigation of structural brain alterations is one focus in research of brain diseases like depression. Voxel-based morphometry (VBM) based on high-resolution 3D MRI images is a widely used non-invasive tool for such investigations. However, the result of VBM might be sensitive to local physiological parameters such as regional cerebral blood volume (rCBV) changes. In order to investigate whether rCBV changes may contribute to variation in VBM, we performed analyses in a study with the congenital learned helplessness (cLH) model for long-term findings. The 3D structural and rCBV data were acquired with T2 -weighted rapid acquisition with relaxation enhancement (RARE) pulse sequences. The group effects were determined by standard statistical parametric mapping (SPM) and biological parametric mapping (BPM) and examined further using atlas-based regions. In our genetic animal model of depression, we found co-occurrence of differences in gray matter volume and rCBV, while there was no evidence of significant interaction between both. However, the multimodal analysis showed similar gray matter differences compared with the standard VBM approach. Our data corroborate the idea that two group VBM differences might not be influenced by rCBV differences in genetically different strains. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27074152

  1. Regional White Matter Decreases in Alzheimer's Disease Using Optimized Voxel-Based Morphometry

    International Nuclear Information System (INIS)

    Background: Most studies that attempt to clarify structural abnormalities related to functional disconnection in patients with Alzheimer's disease (AD) have focused on exploring pathological changes in cortical gray matter. However, white matter fibers connecting these cerebral areas may also be abnormal. Purpose: To investigate the regional changes of white matter volume in patients with AD compared to healthy subjects. Material and Methods: White matter volume changes in whole-brain magnetic resonance images acquired from 19 patients with AD and 20 healthy subjects (control group) were observed using the optimized voxel-based morphometry (VBM) method. In addition, the corpus callosum (CC) of AD patients and the control group was investigated further by outlining manually the boundary of the CC on a midsagittal slice. Each area of the CC was then corrected by dividing each subject's intracranial area in the midsagittal plane. Results: Compared with the control group, AD patients showed significantly reduced white matter volumes in the posterior part of the CC and the temporal lobe in the left and right hemispheres. Moreover, the voxel showing peak statistical difference in the posterior of the CC was left sided. The five subdivisions of the CC were also significantly smaller among the AD patients relative to the control group. Conclusion: Our findings suggest that these abnormalities in white matter regions may contribute to the functional disconnections in AD

  2. Grey matter abnormalities in untreated hyperthyroidism: A voxel-based morphometry study using the DARTEL approach

    International Nuclear Information System (INIS)

    Objective: Hyperthyroidism is frequently associated with pronounced neuropsychiatric symptoms such as impulsiveness, irritability, poor concentration, and memory impairments. Functional neuroimaging has revealed changes in cerebral metabolism in hyperthyroidism, but regional changes in cortical morphology associated with specific neurological deficits have not been studied so far. To investigate the pathophysiology underlying hyperthyroid-associated neural dysfunction, we compared grey matter volume (GMV) between adult hyperthyroid patients and matched healthy controls using voxel-based morphometry (VBM). Materials and methods: High resolution 3D T1-weighted images were acquired by 3T MRI from 51 hyperthyroid patients and 51 controls. VBM analysis was performed using SPM8. Correlations between regional GMV and both serum free thyroid hormone (TH) concentrations and disease duration were assessed by multiple regression analysis. Results: Compared to controls, GM volumes in the bilateral hippocampus, parahippocampal gyrus, calcarine, lingual gyrus, and left temporal pole were lower and bilateral supplementary motor area GMV higher in hyperthyroid patients. Serum free triiodothyronine (FT3) concentration was negatively correlated with the normalized regional volume (NRV) of the left parahippocampal gyrus and serum free thyroxine (FT4) concentration negatively correlated with the NRV of the left hippocampus and right parahippocampal gyrus. Disease duration was negatively correlated with the NRV of the left hippocampus, bilateral parahippocampal gyrus, and left temporal pole. Conclusion: Hyperthyroid patients exhibited reduced GMV in regions associated with memory, attention, emotion, vision, and motor planning. Negative correlations between GMV and both free TH and disease duration suggest that chronic TH elevation induces abnormalities in the adult cortex

  3. Focal retrograde amnesia: voxel-based morphometry findings in a case without MRI lesions.

    Science.gov (United States)

    Sehm, Bernhard; Frisch, Stefan; Thöne-Otto, Angelika; Horstmann, Annette; Villringer, Arno; Obrig, Hellmuth

    2011-01-01

    Focal retrograde amnesia (FRA) is a rare neurocognitive disorder presenting with an isolated loss of retrograde memory. In the absence of detectable brain lesions, a differentiation of FRA from psychogenic causes is difficult. Here we report a case study of persisting FRA after an epileptic seizure. A thorough neuropsychological assessment confirmed severe retrograde memory deficits while anterograde memory abilities were completely normal. Neurological and psychiatric examination were unremarkable and high-resolution MRI showed no neuroradiologically apparent lesion. However, voxel-based morphometry (VBM)-comparing the MRI to an education-, age-and sex-matched control group (n = 20) disclosed distinct gray matter decreases in left temporopolar cortex and a region between right posterior parahippocampal and lingual cortex. Although the results of VBM-based comparisons between a single case and a healthy control group are generally susceptible to differences unrelated to the specific symptoms of the case, we believe that our data suggest a causal role of the cortical areas detected since the retrograde memory deficit is the preeminent neuropsychological difference between patient and controls. This was paralleled by grey matter differences in central nodes of the retrograde memory network. We therefore suggest that these subtle alterations represent structural correlates of the focal retrograde amnesia in our patient. Beyond the implications for the diagnosis and etiology of FRA, our results advocate the use of VBM in conditions that do not show abnormalities in clinical radiological assessment, but show distinct neuropsychological deficits. PMID:22028902

  4. The correlation between gray matter volume and perceived social support: a voxel-based morphometry study.

    Science.gov (United States)

    Che, XianWei; Wei, DongTao; Li, WenFu; Li, HaiJiang; Qiao, Lei; Qiu, Jiang; Zhang, QingLin; Liu, YiJun

    2014-01-01

    Social support refers to interpersonal exchanges that include the combinations of aid, affirmation and affection. Perceived social support is a kind of subjective judgment of one's availability of social support. In spite of the importance of perceived social support to health, however, its neural substrate remains unknown. To address this question, voxel-based morphometry was employed to investigate the neural bases of individual differences in responses to the Perceived Social Support Scale (PSSS) in healthy volunteers (144 men and 203 women; mean age = 19.9; SD = 1.33, age range : 17-27). As a result, multiple regression analysis revealed that the PSSS scores were significantly and positively correlated with gray matter volume in a cluster that mainly included areas in posterior parts of posterior cingulate cortex, bilateral lingual cortex, left occipital lobe and cuneus. Highly-supported individuals had larger gray matter volume in these brain regions, implying a relatively high level of ability to engage in self-referential processes and social cognition. Our results provide a biological basis for exploring perceived social support particularly in relationship to various health parameters and outcomes. PMID:24397344

  5. Gray matter correlates of creative potential: a latent variable voxel-based morphometry study.

    Science.gov (United States)

    Jauk, Emanuel; Neubauer, Aljoscha C; Dunst, Beate; Fink, Andreas; Benedek, Mathias

    2015-05-01

    There is increasing research interest in the structural and functional brain correlates underlying creative potential. Recent investigations found that interindividual differences in creative potential relate to volumetric differences in brain regions belonging to the default mode network, such as the precuneus. Yet, the complex interplay between creative potential, intelligence, and personality traits and their respective neural bases is still under debate. We investigated regional gray matter volume (rGMV) differences that can be associated with creative potential in a heterogeneous sample of N=135 individuals using voxel-based morphometry (VBM). By means of latent variable modeling and consideration of recent psychometric advancements in creativity research, we sought to disentangle the effects of ideational originality and fluency as two independent indicators of creative potential. Intelligence and openness to experience were considered as common covariates of creative potential. The results confirmed and extended previous research: rGMV in the precuneus was associated with ideational originality, but not with ideational fluency. In addition, we found ideational originality to be correlated with rGMV in the caudate nucleus. The results indicate that the ability to produce original ideas is tied to default-mode as well as dopaminergic structures. These structural brain correlates of ideational originality were apparent throughout the whole range of intellectual ability and thus not moderated by intelligence. In contrast, structural correlates of ideational fluency, a quantitative marker of creative potential, were observed only in lower intelligent individuals in the cuneus/lingual gyrus. PMID:25676914

  6. Creation of voxel-based models for paediatric dosimetry from automatic segmentation methods

    International Nuclear Information System (INIS)

    Full text: The first computational models representing human anatomy were mathematical phantoms, but still far from accurate representations of human body. These models have been used with radiation transport codes (Monte Carlo) to estimate organ doses from radiological procedures. Although new medical imaging techniques have recently allowed the construction of voxel-based models based on the real anatomy, few children models from individual CT or MRI data have been reported [1,3]. For pediatric dosimetry purposes, a large range of voxel models by ages is required since scaling the anatomy from existing models is not sufficiently accurate. The small number of models available arises from the small number of CT or MRI data sets of children available and the long amount of time required to segment the data sets. The existing models have been constructed by manual segmentation slice by slice and using simple thresholding techniques. In medical image segmentation, considerable difficulties appear when applying classical techniques like thresholding or simple edge detection. Until now, any evidence of more accurate or near-automatic methods used in construction of child voxel models exists. We aim to construct a range of pediatric voxel models, integrating automatic or semi-automatic 3D segmentation techniques. In this paper we present the first stage of this work using pediatric CT data.

  7. Voxel-based morphometry findings in Alzheimer's disease: neuropsychiatric symptoms and disability correlations - preliminary results

    Directory of Open Access Journals (Sweden)

    Luciano de Gois Vasconcelos

    2011-01-01

    Full Text Available INTRODUCTION: The role of structural brain changes and their correlations with neuropsychiatric symptoms and disability in Alzheimer's disease are still poorly understood. OBJECTIVE: To establish whether structural changes in grey matter volume in patients with mild Alzheimer's disease are associated with neuropsychiatric symptoms and disability METHODS: Nineteen Alzheimer's disease patients (9 females; total mean age =75.2 y old +4.7; total mean education level =8.5 y +4.9 underwent a magnetic resonance imaging (MRI examination and voxel-based morphometry analysis. T1-weighted images were spatially normalized and segmented. Grey matter images were smoothed and analyzed using a multiple regression design. The results were corrected for multiple comparisons. The Neuropsychiatric Inventory was used to evaluate the neuropsychiatric symptoms, and the Functional Activities Questionnaire and Disability Assessment for Dementia were used for functional evaluation RESULTS: A significant negative correlation was found between the bilateral middle frontal gyri, left inferior temporal gyrus, right orbitofrontal gyrus, and Neuropsychiatric Inventory scores. A negative correlation was found between bilateral middle temporal gyri, left hippocampus, bilateral fusiform gyri, and the Functional Activities Questionnaire. There was a positive correlation between the right amygdala, bilateral fusiform gyri, right anterior insula, left inferior and middle temporal gyri, right superior temporal gyrus, and Disability Assessment for Dementia scores CONCLUSIONS: The results suggest that the neuropsychiatric symptoms observed in Alzheimer's disease patients could be mainly due to frontal structural abnormalities, whereas disability could be associated with reductions in temporal structures.

  8. Regional White Matter Decreases in Alzheimer's Disease Using Optimized Voxel-Based Morphometry

    Energy Technology Data Exchange (ETDEWEB)

    Shuyu Li; Fang Pu; Feng Shi; Sheng Xie; Yinhua Wang; Tianzi Jiang (Dept. of Bioengineering, Beijing Univ. of Aeronautics and Astronautics, Beijing (China))

    2008-02-15

    Background: Most studies that attempt to clarify structural abnormalities related to functional disconnection in patients with Alzheimer's disease (AD) have focused on exploring pathological changes in cortical gray matter. However, white matter fibers connecting these cerebral areas may also be abnormal. Purpose: To investigate the regional changes of white matter volume in patients with AD compared to healthy subjects. Material and Methods: White matter volume changes in whole-brain magnetic resonance images acquired from 19 patients with AD and 20 healthy subjects (control group) were observed using the optimized voxel-based morphometry (VBM) method. In addition, the corpus callosum (CC) of AD patients and the control group was investigated further by outlining manually the boundary of the CC on a midsagittal slice. Each area of the CC was then corrected by dividing each subject's intracranial area in the midsagittal plane. Results: Compared with the control group, AD patients showed significantly reduced white matter volumes in the posterior part of the CC and the temporal lobe in the left and right hemispheres. Moreover, the voxel showing peak statistical difference in the posterior of the CC was left sided. The five subdivisions of the CC were also significantly smaller among the AD patients relative to the control group. Conclusion: Our findings suggest that these abnormalities in white matter regions may contribute to the functional disconnections in AD

  9. Regional White Matter Decreases in Alzheimer's Disease Using Optimized Voxel-Based Morphometry

    Energy Technology Data Exchange (ETDEWEB)

    Shuyu Li; Fang Pu; Feng Shi; Sheng Xie; Yinhua Wang; Tianzi Jiang [Dept. of Bioengineering, Beijing Univ. of Aeronautics and Astronautics, Beijing (China)

    2008-02-15

    Background: Most studies that attempt to clarify structural abnormalities related to functional disconnection in patients with Alzheimer's disease (AD) have focused on exploring pathological changes in cortical gray matter. However, white matter fibers connecting these cerebral areas may also be abnormal. Purpose: To investigate the regional changes of white matter volume in patients with AD compared to healthy subjects. Material and Methods: White matter volume changes in whole-brain magnetic resonance images acquired from 19 patients with AD and 20 healthy subjects (control group) were observed using the optimized voxel-based morphometry (VBM) method. In addition, the corpus callosum (CC) of AD patients and the control group was investigated further by outlining manually the boundary of the CC on a midsagittal slice. Each area of the CC was then corrected by dividing each subject's intracranial area in the midsagittal plane. Results: Compared with the control group, AD patients showed significantly reduced white matter volumes in the posterior part of the CC and the temporal lobe in the left and right hemispheres. Moreover, the voxel showing peak statistical difference in the posterior of the CC was left sided. The five subdivisions of the CC were also significantly smaller among the AD patients relative to the control group. Conclusion: Our findings suggest that these abnormalities in white matter regions may contribute to the functional disconnections in AD.

  10. Voxel-Based Morphometric Study on Chinese Blind Men's Brain Structure

    Institute of Scientific and Technical Information of China (English)

    YANG Chun-lan; PAN Wen-ju; ZHENG Lian

    2007-01-01

    Many studies have shown the functional relevance of cross-modal plasticity in blind men.In order to study the changes of their brain structure,voxel-based morphometry (VBM) methods are used.The regional gray matter (GM) and white matter (WM) concentrations of magnetic resonance (MR) images from 11 blind people and 9 sighted control subjects are compared using standard VBM.Optimized VBM is also discussed to measure the absolute local volume of GM or WM.Consistent results are achieved by statistical analysis with these methods.There are distinct differences not only in visual cortex but also the sensory area,auditory area and motor area.GM concentrations in blind men significantly decreased in Brodmann 7 and 22.While in Brodmann 18 and 19,GM concentration increased.GM volumes decreased in Brodmann 3,4,6,9 and 45.On the other hand,both WM concentration and volume increased in Brodmann 7.These results suggest that early visual deprivation can lead to changes in the brain structural anatomy which is consistent with the cortical cross-modal reorganization found by functional imaging.It may help to discover the relationship between the brain structural anatomy and the brain functional data of blind men at a macroscopic level from neuroimaging perspective.

  11. Whole-brain voxel-based morphometry study of children and adolescents with Down syndrome

    Science.gov (United States)

    Carducci, Filippo; Onorati, Paolo; Condoluci, Claudia; Di Gennaro, Giancarlo; Quarato, Pier Paolo; Pierallini, Alberto; Sarà, Marco; Miano, Silvia; Cornia, Riccardo; Albertini, Giorgio

    2013-01-01

    Summary In order to investigate alterations in brain morphology and a possible temporal pattern of neuroanatomical abnormalities in the gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF) of young patients with Down syndrome (DS), high-resolution magnetic resonance imaging (MRI) voxel-based morphometry (VBM) was performed on 21 children and adolescents with this chromosomal aberration and 27 age-matched participants as controls. In comparison with control subjects, children and adolescents with DS showed not only an overall smaller whole-brain volume, but also volume reductions of the GM in the cerebellum, frontal lobes, frontal region of the limbic lobe, parahippocampal gyri and hippocampi and of the WM in the cerebellum, frontal and parietal lobes, sub-lobar regions and brainstem. By contrast, volume preservation was observed in the GM of the parietal lobes, temporal lobe and sub-lobar regions and in the WM of the temporal lobe and temporal regions of the limbic lobe. A lower volume of CSF was also detected in the frontal lobes. This study is the first to use the high-resolution MRI VBM method to describe a whole-brain pattern of abnormalities in young DS patients falling within such a narrow age range and it provides new information on the neuroanatomically specific regional changes that occur during development in these patients. PMID:23731912

  12. Focal retrograde amnesia: voxel-based morphometry findings in a case without MRI lesions.

    Directory of Open Access Journals (Sweden)

    Bernhard Sehm

    Full Text Available Focal retrograde amnesia (FRA is a rare neurocognitive disorder presenting with an isolated loss of retrograde memory. In the absence of detectable brain lesions, a differentiation of FRA from psychogenic causes is difficult. Here we report a case study of persisting FRA after an epileptic seizure. A thorough neuropsychological assessment confirmed severe retrograde memory deficits while anterograde memory abilities were completely normal. Neurological and psychiatric examination were unremarkable and high-resolution MRI showed no neuroradiologically apparent lesion. However, voxel-based morphometry (VBM-comparing the MRI to an education-, age-and sex-matched control group (n = 20 disclosed distinct gray matter decreases in left temporopolar cortex and a region between right posterior parahippocampal and lingual cortex. Although the results of VBM-based comparisons between a single case and a healthy control group are generally susceptible to differences unrelated to the specific symptoms of the case, we believe that our data suggest a causal role of the cortical areas detected since the retrograde memory deficit is the preeminent neuropsychological difference between patient and controls. This was paralleled by grey matter differences in central nodes of the retrograde memory network. We therefore suggest that these subtle alterations represent structural correlates of the focal retrograde amnesia in our patient. Beyond the implications for the diagnosis and etiology of FRA, our results advocate the use of VBM in conditions that do not show abnormalities in clinical radiological assessment, but show distinct neuropsychological deficits.

  13. Parallel solutions for voxel-based simulations of reaction-diffusion systems.

    Science.gov (United States)

    D'Agostino, Daniele; Pasquale, Giulia; Clematis, Andrea; Maj, Carlo; Mosca, Ettore; Milanesi, Luciano; Merelli, Ivan

    2014-01-01

    There is an increasing awareness of the pivotal role of noise in biochemical processes and of the effect of molecular crowding on the dynamics of biochemical systems. This necessity has given rise to a strong need for suitable and sophisticated algorithms for the simulation of biological phenomena taking into account both spatial effects and noise. However, the high computational effort characterizing simulation approaches, coupled with the necessity to simulate the models several times to achieve statistically relevant information on the model behaviours, makes such kind of algorithms very time-consuming for studying real systems. So far, different parallelization approaches have been deployed to reduce the computational time required to simulate the temporal dynamics of biochemical systems using stochastic algorithms. In this work we discuss these aspects for the spatial TAU-leaping in crowded compartments (STAUCC) simulator, a voxel-based method for the stochastic simulation of reaction-diffusion processes which relies on the Sτ-DPP algorithm. In particular we present how the characteristics of the algorithm can be exploited for an effective parallelization on the present heterogeneous HPC architectures. PMID:25045716

  14. Parallel Solutions for Voxel-Based Simulations of Reaction-Diffusion Systems

    Directory of Open Access Journals (Sweden)

    Daniele D’Agostino

    2014-01-01

    Full Text Available There is an increasing awareness of the pivotal role of noise in biochemical processes and of the effect of molecular crowding on the dynamics of biochemical systems. This necessity has given rise to a strong need for suitable and sophisticated algorithms for the simulation of biological phenomena taking into account both spatial effects and noise. However, the high computational effort characterizing simulation approaches, coupled with the necessity to simulate the models several times to achieve statistically relevant information on the model behaviours, makes such kind of algorithms very time-consuming for studying real systems. So far, different parallelization approaches have been deployed to reduce the computational time required to simulate the temporal dynamics of biochemical systems using stochastic algorithms. In this work we discuss these aspects for the spatial TAU-leaping in crowded compartments (STAUCC simulator, a voxel-based method for the stochastic simulation of reaction-diffusion processes which relies on the Sτ-DPP algorithm. In particular we present how the characteristics of the algorithm can be exploited for an effective parallelization on the present heterogeneous HPC architectures.

  15. Voxel-Based Morphometry ALE meta-analysis of Bipolar Disorder

    Science.gov (United States)

    Magana, Omar; Laird, Robert

    2012-03-01

    A meta-analysis was performed independently to view the changes in gray matter (GM) on patients with Bipolar disorder (BP). The meta-analysis was conducted on a Talairach Space using GingerALE to determine the voxels and their permutation. In order to achieve the data acquisition, published experiments and similar research studies were uploaded onto the online Voxel-Based Morphometry database (VBM). By doing so, coordinates of activation locations were extracted from Bipolar disorder related journals utilizing Sleuth. Once the coordinates of given experiments were selected and imported to GingerALE, a Gaussian was performed on all foci points to create the concentration points of GM on BP patients. The results included volume reductions and variations of GM between Normal Healthy controls and Patients with Bipolar disorder. A significant amount of GM clusters were obtained in Normal Healthy controls over BP patients on the right precentral gyrus, right anterior cingulate, and the left inferior frontal gyrus. In future research, more published journals could be uploaded onto the database and another VBM meta-analysis could be performed including more activation coordinates or a variation of age groups.

  16. Meditation effects within the hippocampal complex revealed by voxel-based morphometry and cytoarchitectonic probabilistic mapping

    Directory of Open Access Journals (Sweden)

    Eileen eLuders

    2013-07-01

    Full Text Available Scientific studies addressing anatomical variations in meditators’ brains have emerged rapidly over the last few years, where significant links are most frequently reported with respect to gray matter (GM. To advance prior work, this study examined GM characteristics in a large sample of 100 subjects (50 meditators, 50 controls, where meditators have been practicing close to twenty years, on average. A standard, whole-brain voxel-based morphometry approach was applied and revealed significant meditation effects in the vicinity of the hippocampus, showing more GM in meditators than in controls as well as positive correlations with the number of years practiced. However, the hippocampal complex is regionally segregated by architecture, connectivity, and functional relevance. Thus, to establish differential effects within the hippocampal formation (cornu ammonis, fascia dentate, entorhinal cortex, subiculum as well as the hippocampal-amygdaloid transition area, we utilized refined cytoarchitectonic probabilistic maps of (peri- hippocampal subsections. Significant meditation effects were observed within the subiculum specifically. Since the subiculum is known to play a key role in stress regulation and meditation is an established form of stress reduction, these GM findings may reflect neuronal preservation in long-term meditators – perhaps due to an attenuated release of stress hormones and decreased neurotoxicity.

  17. Meditation effects within the hippocampal complex revealed by voxel-based morphometry and cytoarchitectonic probabilistic mapping.

    Science.gov (United States)

    Luders, Eileen; Kurth, Florian; Toga, Arthur W; Narr, Katherine L; Gaser, Christian

    2013-01-01

    Scientific studies addressing anatomical variations in meditators' brains have emerged rapidly over the last few years, where significant links are most frequently reported with respect to gray matter (GM). To advance prior work, this study examined GM characteristics in a large sample of 100 subjects (50 meditators, 50 controls), where meditators have been practicing close to 20 years, on average. A standard, whole-brain voxel-based morphometry approach was applied and revealed significant meditation effects in the vicinity of the hippocampus, showing more GM in meditators than in controls as well as positive correlations with the number of years practiced. However, the hippocampal complex is regionally segregated by architecture, connectivity, and functional relevance. Thus, to establish differential effects within the hippocampal formation (cornu ammonis, fascia dentata, entorhinal cortex, subiculum) as well as the hippocampal-amygdaloid transition area, we utilized refined cytoarchitectonic probabilistic maps of (peri-) hippocampal subsections. Significant meditation effects were observed within the subiculum specifically. Since the subiculum is known to play a key role in stress regulation and meditation is an established form of stress reduction, these GM findings may reflect neuronal preservation in long-term meditators-perhaps due to an attenuated release of stress hormones and decreased neurotoxicity. PMID:23847572

  18. The neuroanatomical basis of panic disorder and social phobia in schizophrenia: a voxel based morphometric study.

    Directory of Open Access Journals (Sweden)

    Marisol Picado

    Full Text Available It is known that there is a high prevalence of certain anxiety disorders among schizophrenic patients, especially panic disorder and social phobia. However, the neural underpinnings of the comorbidity of such anxiety disorders and schizophrenia remain unclear. Our study aims to determine the neuroanatomical basis of the co-occurrence of schizophrenia with panic disorder and social phobia.Voxel-based morphometry was used in order to examine brain structure and to measure between-group differences, comparing magnetic resonance images of 20 anxious patients, 20 schizophrenic patients, 20 schizophrenic patients with comorbid anxiety, and 20 healthy control subjects.Compared to the schizophrenic patients, we observed smaller grey-matter volume (GMV decreases in the dorsolateral prefrontal cortex and precentral gyrus in the schizophrenic-anxiety group. Additionally, the schizophrenic group showed significantly reduced GMV in the dorsolateral prefrontal cortex, precentral gyrus, orbitofrontal cortex, temporal gyrus and angular/inferior parietal gyrus when compared to the control group.Our findings suggest that the comorbidity of schizophrenia with panic disorder and social phobia might be characterized by specific neuroanatomical and clinical alterations that may be related to maladaptive emotion regulation related to anxiety. Even thought our findings need to be replicated, our study suggests that the identification of neural abnormalities involved in anxiety, schizophrenia and schizophrenia-anxiety may lead to an improved diagnosis and management of these conditions.

  19. Potential hippocampal region atrophy in diabetes mellitus type 2. A voxel-based morphometry VSRAD study

    International Nuclear Information System (INIS)

    Among diabetes mellitus type 2 (DM2) patients, the frequency of cognitive dysfunction is higher and the relative risk of Alzheimer's disease (AD) is approximately twice that of nondiabetics. Cognitive impairment symptoms of AD are induced by limbic system dysfunction, and an early-stage AD brain without dementia has the potential for atrophy in the hippocampal region. In this study, we estimated potential hippocampal region atrophy in DM2 and pursued the association between DM2 and cognitive impairment/AD. Voxel-based morphometry analysis was performed in 28 diabetics (14 men, 14 women; ages 59-79 years, mean 70.7 years) and 28 sex- and age- matched (±1 year) nondiabetics. Severity of gray matter loss in the hippocampal region and whole brain were investigated. Group analysis was performed using two-tailed unpaired t-test; significance was assumed with less than 1% (P<0.01) of the critical rate. There was a significant difference between diabetics and nondiabetics regarding the severity of hippocampal region atrophy and whole-brain atrophy. Only diabetics showed a positive correlation for severity of hippocampal region atrophy and whole-brain atrophy (rs=0.69, P<0.0001). Aged DM2 patients have the potential for hippocampal region atrophy, and its dysfunction can be related to the expression of a cognitive impairment that resembles AD. (author)

  20. Brain correlates of pro-social personality traits: a voxel-based morphometry study.

    Science.gov (United States)

    Coutinho, Joana F; Sampaio, Adriana; Ferreira, Miguel; Soares, José M; Gonçalves, Oscar F

    2013-09-01

    Of the five personality dimensions described by the Big Five Personality Model (Costa and McCrae 1992), Extraversion and Agreeableness are the traits most commonly associated with a pro-social orientation. In this study we tested whether a pro-social orientation, as expressed in terms of Extraversion and Agreeableness, is associated with a specific grey matter phenotype. Fifty-two healthy participants underwent magnetic resonance imaging (MRI) and completed the NEO-Five Factor Inventory (NEO-FFI), a self-report measure of the Big Five personality traits. Voxel-based morphometry (VBM) was used to investigate the correlation between brain structure and the personality traits of Agreeableness and Extraversion. We found that Extraversion was negatively correlated with grey matter density in the middle frontal and orbitofrontal gyri while Agreeableness was negatively correlated with grey matter density in the inferior parietal, middle occipital and posterior cingulate gyri. No positive correlations were found. These results suggest that pro-social personality traits seem to be associated with decreases in grey matter density in more frontal regions for Extraversion, and more posterior regions for Agreeableness. PMID:23512407

  1. Voxel-based analysis of diffusion tensor indices in the brain in patients with Parkinson's disease

    International Nuclear Information System (INIS)

    Purpose: To investigate the abnormal diffusion in cerebral white matter and its relationship with the olfactory dysfunction in patients with Parkinson's disease (PD) through diffusion tensor imaging (DTI). Materials and methods: Diffusion tensor imaging of the cerebrum was performed in 25 patients with Parkinson's disease and 25 control subjects matched for age and sex. Differences in fractional anisotropy (FA) and mean diffusivity (MD) between these two groups were studied by voxel-based analysis of the DTI data. Correlations between diffusion indices and the olfactory function in PD patients were evaluated using the multiple regression model after controlling for the duration of the disease, Unified Parkinson's Disease Rating Sale (UPDRS), and age. Results: The damaged white and gray matter showed decreased FA or increased MD, localized bilaterally in the cerebellar and orbitofrontal cortex. In addition, in PD patients there was a positive correlation between FA values in the white matter of the left cerebellum and the thresholds of olfactory identification (TOI) and a negative correlation between MD values in the white matter of right cerebellum and the TOI. Conclusion: In patients with PD, there was disruption in the cerebellar white matter which may play an important role in the olfactory dysfunction in patients with Parkinson's disease.

  2. Neural correlates of post-conventional moral reasoning: a voxel-based morphometry study.

    Directory of Open Access Journals (Sweden)

    Kristin Prehn

    Full Text Available Going back to Kohlberg, moral development research affirms that people progress through different stages of moral reasoning as cognitive abilities mature. Individuals at a lower level of moral reasoning judge moral issues mainly based on self-interest (personal interests schema or based on adherence to laws and rules (maintaining norms schema, whereas individuals at the post-conventional level judge moral issues based on deeper principles and shared ideals. However, the extent to which moral development is reflected in structural brain architecture remains unknown. To investigate this question, we used voxel-based morphometry and examined the brain structure in a sample of 67 Master of Business Administration (MBA students. Subjects completed the Defining Issues Test (DIT-2 which measures moral development in terms of cognitive schema preference. Results demonstrate that subjects at the post-conventional level of moral reasoning were characterized by increased gray matter volume in the ventromedial prefrontal cortex and subgenual anterior cingulate cortex, compared with subjects at a lower level of moral reasoning. Our findings support an important role for both cognitive and emotional processes in moral reasoning and provide first evidence for individual differences in brain structure according to the stages of moral reasoning first proposed by Kohlberg decades ago.

  3. Neural correlates of post-conventional moral reasoning: a voxel-based morphometry study.

    Science.gov (United States)

    Prehn, Kristin; Korczykowski, Marc; Rao, Hengyi; Fang, Zhuo; Detre, John A; Robertson, Diana C

    2015-01-01

    Going back to Kohlberg, moral development research affirms that people progress through different stages of moral reasoning as cognitive abilities mature. Individuals at a lower level of moral reasoning judge moral issues mainly based on self-interest (personal interests schema) or based on adherence to laws and rules (maintaining norms schema), whereas individuals at the post-conventional level judge moral issues based on deeper principles and shared ideals. However, the extent to which moral development is reflected in structural brain architecture remains unknown. To investigate this question, we used voxel-based morphometry and examined the brain structure in a sample of 67 Master of Business Administration (MBA) students. Subjects completed the Defining Issues Test (DIT-2) which measures moral development in terms of cognitive schema preference. Results demonstrate that subjects at the post-conventional level of moral reasoning were characterized by increased gray matter volume in the ventromedial prefrontal cortex and subgenual anterior cingulate cortex, compared with subjects at a lower level of moral reasoning. Our findings support an important role for both cognitive and emotional processes in moral reasoning and provide first evidence for individual differences in brain structure according to the stages of moral reasoning first proposed by Kohlberg decades ago. PMID:26039547

  4. Sensitivity study of voxel-based PET image comparison to image registration algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Yip, Stephen, E-mail: syip@lroc.harvard.edu; Chen, Aileen B.; Berbeco, Ross [Department of Radiation Oncology, Brigham and Women’s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States); Aerts, Hugo J. W. L. [Department of Radiation Oncology, Brigham and Women’s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 and Department of Radiology, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2014-11-01

    Purpose: Accurate deformable registration is essential for voxel-based comparison of sequential positron emission tomography (PET) images for proper adaptation of treatment plan and treatment response assessment. The comparison may be sensitive to the method of deformable registration as the optimal algorithm is unknown. This study investigated the impact of registration algorithm choice on therapy response evaluation. Methods: Sixteen patients with 20 lung tumors underwent a pre- and post-treatment computed tomography (CT) and 4D FDG-PET scans before and after chemoradiotherapy. All CT images were coregistered using a rigid and ten deformable registration algorithms. The resulting transformations were then applied to the respective PET images. Moreover, the tumor region defined by a physician on the registered PET images was classified into progressor, stable-disease, and responder subvolumes. Particularly, voxels with standardized uptake value (SUV) decreases >30% were classified as responder, while voxels with SUV increases >30% were progressor. All other voxels were considered stable-disease. The agreement of the subvolumes resulting from difference registration algorithms was assessed by Dice similarity index (DSI). Coefficient of variation (CV) was computed to assess variability of DSI between individual tumors. Root mean square difference (RMS{sub rigid}) of the rigidly registered CT images was used to measure the degree of tumor deformation. RMS{sub rigid} and DSI were correlated by Spearman correlation coefficient (R) to investigate the effect of tumor deformation on DSI. Results: Median DSI{sub rigid} was found to be 72%, 66%, and 80%, for progressor, stable-disease, and responder, respectively. Median DSI{sub deformable} was 63%–84%, 65%–81%, and 82%–89%. Variability of DSI was substantial and similar for both rigid and deformable algorithms with CV > 10% for all subvolumes. Tumor deformation had moderate to significant impact on DSI for progressor

  5. Voxel-based clustered imaging by multiparameter diffusion tensor images for glioma grading

    Directory of Open Access Journals (Sweden)

    Rika Inano

    2014-01-01

    Full Text Available Gliomas are the most common intra-axial primary brain tumour; therefore, predicting glioma grade would influence therapeutic strategies. Although several methods based on single or multiple parameters from diagnostic images exist, a definitive method for pre-operatively determining glioma grade remains unknown. We aimed to develop an unsupervised method using multiple parameters from pre-operative diffusion tensor images for obtaining a clustered image that could enable visual grading of gliomas. Fourteen patients with low-grade gliomas and 19 with high-grade gliomas underwent diffusion tensor imaging and three-dimensional T1-weighted magnetic resonance imaging before tumour resection. Seven features including diffusion-weighted imaging, fractional anisotropy, first eigenvalue, second eigenvalue, third eigenvalue, mean diffusivity and raw T2 signal with no diffusion weighting, were extracted as multiple parameters from diffusion tensor imaging. We developed a two-level clustering approach for a self-organizing map followed by the K-means algorithm to enable unsupervised clustering of a large number of input vectors with the seven features for the whole brain. The vectors were grouped by the self-organizing map as protoclusters, which were classified into the smaller number of clusters by K-means to make a voxel-based diffusion tensor-based clustered image. Furthermore, we also determined if the diffusion tensor-based clustered image was really helpful for predicting pre-operative glioma grade in a supervised manner. The ratio of each class in the diffusion tensor-based clustered images was calculated from the regions of interest manually traced on the diffusion tensor imaging space, and the common logarithmic ratio scales were calculated. We then applied support vector machine as a classifier for distinguishing between low- and high-grade gliomas. Consequently, the sensitivity, specificity, accuracy and area under the curve of receiver operating

  6. Voxel-based clustered imaging by multiparameter diffusion tensor images for glioma grading.

    Science.gov (United States)

    Inano, Rika; Oishi, Naoya; Kunieda, Takeharu; Arakawa, Yoshiki; Yamao, Yukihiro; Shibata, Sumiya; Kikuchi, Takayuki; Fukuyama, Hidenao; Miyamoto, Susumu

    2014-01-01

    Gliomas are the most common intra-axial primary brain tumour; therefore, predicting glioma grade would influence therapeutic strategies. Although several methods based on single or multiple parameters from diagnostic images exist, a definitive method for pre-operatively determining glioma grade remains unknown. We aimed to develop an unsupervised method using multiple parameters from pre-operative diffusion tensor images for obtaining a clustered image that could enable visual grading of gliomas. Fourteen patients with low-grade gliomas and 19 with high-grade gliomas underwent diffusion tensor imaging and three-dimensional T1-weighted magnetic resonance imaging before tumour resection. Seven features including diffusion-weighted imaging, fractional anisotropy, first eigenvalue, second eigenvalue, third eigenvalue, mean diffusivity and raw T2 signal with no diffusion weighting, were extracted as multiple parameters from diffusion tensor imaging. We developed a two-level clustering approach for a self-organizing map followed by the K-means algorithm to enable unsupervised clustering of a large number of input vectors with the seven features for the whole brain. The vectors were grouped by the self-organizing map as protoclusters, which were classified into the smaller number of clusters by K-means to make a voxel-based diffusion tensor-based clustered image. Furthermore, we also determined if the diffusion tensor-based clustered image was really helpful for predicting pre-operative glioma grade in a supervised manner. The ratio of each class in the diffusion tensor-based clustered images was calculated from the regions of interest manually traced on the diffusion tensor imaging space, and the common logarithmic ratio scales were calculated. We then applied support vector machine as a classifier for distinguishing between low- and high-grade gliomas. Consequently, the sensitivity, specificity, accuracy and area under the curve of receiver operating characteristic

  7. Metabolic patterns in prion diseases: an FDG PET voxel-based analysis

    International Nuclear Information System (INIS)

    Clinical diagnosis of human prion diseases can be challenging since symptoms are common to other disorders associated with rapidly progressive dementia. In this context, 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) might be a useful complementary tool. The aim of this study was to determine the metabolic pattern in human prion diseases, particularly sporadic Creutzfeldt-Jakob disease (sCJD), the new variant of Creutzfeldt-Jakob disease (vCJD) and fatal familial insomnia (FFI). We retrospectively studied 17 patients with a definitive, probable or possible prion disease who underwent FDG PET in our institution. Of these patients, 12 were diagnosed as sCJD (9 definitive, 2 probable and 1 possible), 1 was diagnosed as definitive vCJD and 4 were diagnosed as definitive FFI. The hypometabolic pattern of each individual and comparisons across the groups of subjects (control subjects, sCJD and FFI) were evaluated using a voxel-based analysis. The sCJD group exhibited a pattern of hypometabolism that affected both subcortical (bilateral caudate, thalamus) and cortical (frontal cortex) structures, while the FFI group only presented a slight hypometabolism in the thalamus. Individual analysis demonstrated a considerable variability of metabolic patterns among patients, with the thalamus and basal ganglia the most frequently affected areas, combined in some cases with frontal and temporal hypometabolism. Patients with a prion disease exhibit a characteristic pattern of brain metabolism presentation in FDG PET imaging. Consequently, in patients with rapidly progressive cognitive impairment, the detection of these patterns in the FDG PET study could orient the diagnosis to a prion disease. (orig.)

  8. Regional Grey Matter Structure Differences between Transsexuals and Healthy Controls—A Voxel Based Morphometry Study

    Science.gov (United States)

    Simon, Lajos; Kozák, Lajos R.; Simon, Viktória; Czobor, Pál; Unoka, Zsolt; Szabó, Ádám; Csukly, Gábor

    2013-01-01

    Gender identity disorder (GID) refers to transsexual individuals who feel that their assigned biological gender is incongruent with their gender identity and this cannot be explained by any physical intersex condition. There is growing scientific interest in the last decades in studying the neuroanatomy and brain functions of transsexual individuals to better understand both the neuroanatomical features of transsexualism and the background of gender identity. So far, results are inconclusive but in general, transsexualism has been associated with a distinct neuroanatomical pattern. Studies mainly focused on male to female (MTF) transsexuals and there is scarcity of data acquired on female to male (FTM) transsexuals. Thus, our aim was to analyze structural MRI data with voxel based morphometry (VBM) obtained from both FTM and MTF transsexuals (n = 17) and compare them to the data of 18 age matched healthy control subjects (both males and females). We found differences in the regional grey matter (GM) structure of transsexual compared with control subjects, independent from their biological gender, in the cerebellum, the left angular gyrus and in the left inferior parietal lobule. Additionally, our findings showed that in several brain areas, regarding their GM volume, transsexual subjects did not differ significantly from controls sharing their gender identity but were different from those sharing their biological gender (areas in the left and right precentral gyri, the left postcentral gyrus, the left posterior cingulate, precuneus and calcarinus, the right cuneus, the right fusiform, lingual, middle and inferior occipital, and inferior temporal gyri). These results support the notion that structural brain differences exist between transsexual and healthy control subjects and that majority of these structural differences are dependent on the biological gender. PMID:24391851

  9. Metabolic patterns in prion diseases: an FDG PET voxel-based analysis

    Energy Technology Data Exchange (ETDEWEB)

    Prieto, Elena; Dominguez-Prado, Ines; Jesus Ribelles, Maria; Arbizu, Javier [Clinica Universidad de Navarra, Nuclear Medicine Department, Pamplona (Spain); Riverol, Mario; Ortega-Cubero, Sara; Rosario Luquin, Maria; Castro, Purificacion de [Clinica Universidad de Navarra, Neurology Department, Pamplona (Spain)

    2015-09-15

    Clinical diagnosis of human prion diseases can be challenging since symptoms are common to other disorders associated with rapidly progressive dementia. In this context, {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET) might be a useful complementary tool. The aim of this study was to determine the metabolic pattern in human prion diseases, particularly sporadic Creutzfeldt-Jakob disease (sCJD), the new variant of Creutzfeldt-Jakob disease (vCJD) and fatal familial insomnia (FFI). We retrospectively studied 17 patients with a definitive, probable or possible prion disease who underwent FDG PET in our institution. Of these patients, 12 were diagnosed as sCJD (9 definitive, 2 probable and 1 possible), 1 was diagnosed as definitive vCJD and 4 were diagnosed as definitive FFI. The hypometabolic pattern of each individual and comparisons across the groups of subjects (control subjects, sCJD and FFI) were evaluated using a voxel-based analysis. The sCJD group exhibited a pattern of hypometabolism that affected both subcortical (bilateral caudate, thalamus) and cortical (frontal cortex) structures, while the FFI group only presented a slight hypometabolism in the thalamus. Individual analysis demonstrated a considerable variability of metabolic patterns among patients, with the thalamus and basal ganglia the most frequently affected areas, combined in some cases with frontal and temporal hypometabolism. Patients with a prion disease exhibit a characteristic pattern of brain metabolism presentation in FDG PET imaging. Consequently, in patients with rapidly progressive cognitive impairment, the detection of these patterns in the FDG PET study could orient the diagnosis to a prion disease. (orig.)

  10. Regional grey matter structure differences between transsexuals and healthy controls--a voxel based morphometry study.

    Science.gov (United States)

    Simon, Lajos; Kozák, Lajos R; Simon, Viktória; Czobor, Pál; Unoka, Zsolt; Szabó, Ádám; Csukly, Gábor

    2013-01-01

    Gender identity disorder (GID) refers to transsexual individuals who feel that their assigned biological gender is incongruent with their gender identity and this cannot be explained by any physical intersex condition. There is growing scientific interest in the last decades in studying the neuroanatomy and brain functions of transsexual individuals to better understand both the neuroanatomical features of transsexualism and the background of gender identity. So far, results are inconclusive but in general, transsexualism has been associated with a distinct neuroanatomical pattern. Studies mainly focused on male to female (MTF) transsexuals and there is scarcity of data acquired on female to male (FTM) transsexuals. Thus, our aim was to analyze structural MRI data with voxel based morphometry (VBM) obtained from both FTM and MTF transsexuals (n = 17) and compare them to the data of 18 age matched healthy control subjects (both males and females). We found differences in the regional grey matter (GM) structure of transsexual compared with control subjects, independent from their biological gender, in the cerebellum, the left angular gyrus and in the left inferior parietal lobule. Additionally, our findings showed that in several brain areas, regarding their GM volume, transsexual subjects did not differ significantly from controls sharing their gender identity but were different from those sharing their biological gender (areas in the left and right precentral gyri, the left postcentral gyrus, the left posterior cingulate, precuneus and calcarinus, the right cuneus, the right fusiform, lingual, middle and inferior occipital, and inferior temporal gyri). These results support the notion that structural brain differences exist between transsexual and healthy control subjects and that majority of these structural differences are dependent on the biological gender. PMID:24391851

  11. Brain structure in post-traumatic stress disorder: A voxel-based morphometry analysis.

    Science.gov (United States)

    Tan, Liwen; Zhang, Li; Qi, Rongfeng; Lu, Guangming; Li, Lingjiang; Liu, Jun; Li, Weihui

    2013-09-15

    This study compared the difference in brain structure in 12 mine disaster survivors with chronic post-traumatic stress disorder, 7 cases of improved post-traumatic stress disorder symptoms, and 14 controls who experienced the same mine disaster but did not suffer post-traumatic stress disorder, using the voxel-based morphometry method. The correlation between differences in brain structure and post-traumatic stress disorder symptoms was also investigated. Results showed that the gray matter volume was the highest in the trauma control group, followed by the symptoms-improved group, and the lowest in the chronic post-traumatic stress disorder group. Compared with the symptoms-improved group, the gray matter volume in the lingual gyrus of the right occipital lobe was reduced in the chronic post-traumatic stress disorder group. Compared with the trauma control group, the gray matter volume in the right middle occipital gyrus and left middle frontal gyrus was reduced in the symptoms-improved group. Compared with the trauma control group, the gray matter volume in the left superior parietal lobule and right superior frontal gyrus was reduced in the chronic post-traumatic stress disorder group. The gray matter volume in the left superior parietal lobule was significantly positively correlated with the State-Trait Anxiety Inventory subscale score in the symptoms-improved group and chronic post-traumatic stress disorder group (r = 0.477, P = 0.039). Our findings indicate that (1) chronic post-traumatic stress disorder patients have gray matter structural damage in the prefrontal lobe, occipital lobe, and parietal lobe, (2) after post-traumatic stress, the disorder symptoms are improved and gray matter structural damage is reduced, but cannot recover to the trauma-control level, and (3) the superior parietal lobule is possibly associated with chronic post-traumatic stress disorder. Post-traumatic stress disorder patients exhibit gray matter abnormalities. PMID:25206550

  12. Juggling revisited - a voxel-based morphometry study with expert jugglers.

    Science.gov (United States)

    Gerber, P; Schlaffke, L; Heba, S; Greenlee, M W; Schultz, T; Schmidt-Wilcke, T

    2014-07-15

    Juggling is a highly interesting tool to investigate neuroplasticity associated with motor-learning. Several brain-imaging studies have reported changes in regional brain morphology in visual association cortices in individuals learning how to juggle a three-ball cascade. However, to our knowledge there are no studies that investigated expert jugglers, looking for specific features in regional brain morphology related to this highly specialized skill. Using T1-weighted images and voxel-based morphometry we investigated in a cross-sectional study design 16 expert jugglers, able to juggle at least five balls and an age- and gender-matched group of non-jugglers. We hypothesized that expert jugglers would show higher gray matter density in regions involved in visual motion perception and eye-hand coordination. Images were pre-processed and analyzed using SPM8. Age was included in the analyses as covariate of no interest. As compared to controls jugglers displayed several clusters of higher, regional gray matter density in the occipital and parietal lobes including the secondary visual cortex, the hMT+/V5 area bilaterally and the intraparietal sulcus bilaterally. Within the jugglers group we also found a correlation between performance and regional gray matter density in the right hMT+/V5 area. Our study provides evidence that expert jugglers show increased gray matter density in brain regions involved in visual motion perception and eye-hand coordination, i.e. brain areas that have previously been shown to undergo dynamic changes in terms of gray matter increases in subjects learning a basic three-ball cascade. The extent to which transient increases in beginners and the differences in experts and non-experts are based on the same neurobiological correlates remains to be fully elucidated. PMID:24736178

  13. Voxel-based lesion-symptom mapping of stroke lesions underlying somatosensory deficits

    Directory of Open Access Journals (Sweden)

    Sarah Meyer

    2016-01-01

    Full Text Available The aim of this study was to investigate the relationship between stroke lesion location and the resulting somatosensory deficit. We studied exteroceptive and proprioceptive somatosensory symptoms and stroke lesions in 38 patients with first-ever acute stroke. The Erasmus modified Nottingham Sensory Assessment was used to clinically evaluate somatosensory functioning in the arm and hand within the first week after stroke onset. Additionally, more objective measures such as the perceptual threshold of touch and somatosensory evoked potentials were recorded. Non-parametric voxel-based lesion-symptom mapping was performed to investigate lesion contribution to different somatosensory deficits in the upper limb. Additionally, structural connectivity of brain areas that demonstrated the strongest association with somatosensory symptoms was determined, using probabilistic fiber tracking based on diffusion tensor imaging data from a healthy age-matched sample. Voxels with a significant association to somatosensory deficits were clustered in two core brain regions: the central parietal white matter, also referred to as the sensory component of the superior thalamic radiation, and the parietal operculum close to the insular cortex, representing the secondary somatosensory cortex. Our objective recordings confirmed findings from clinical assessments. Probabilistic tracking connected the first region to thalamus, internal capsule, brain stem, postcentral gyrus, cerebellum, and frontal pathways, while the second region demonstrated structural connections to thalamus, insular and primary somatosensory cortex. This study reveals that stroke lesions in the sensory fibers of the superior thalamocortical radiation and the parietal operculum are significantly associated with multiple exteroceptive and proprioceptive deficits in the arm and hand.

  14. Voxel-based lesion-symptom mapping of stroke lesions underlying somatosensory deficits.

    Science.gov (United States)

    Meyer, Sarah; Kessner, Simon S; Cheng, Bastian; Bönstrup, Marlene; Schulz, Robert; Hummel, Friedhelm C; De Bruyn, Nele; Peeters, Andre; Van Pesch, Vincent; Duprez, Thierry; Sunaert, Stefan; Schrooten, Maarten; Feys, Hilde; Gerloff, Christian; Thomalla, Götz; Thijs, Vincent; Verheyden, Geert

    2016-01-01

    The aim of this study was to investigate the relationship between stroke lesion location and the resulting somatosensory deficit. We studied exteroceptive and proprioceptive somatosensory symptoms and stroke lesions in 38 patients with first-ever acute stroke. The Erasmus modified Nottingham Sensory Assessment was used to clinically evaluate somatosensory functioning in the arm and hand within the first week after stroke onset. Additionally, more objective measures such as the perceptual threshold of touch and somatosensory evoked potentials were recorded. Non-parametric voxel-based lesion-symptom mapping was performed to investigate lesion contribution to different somatosensory deficits in the upper limb. Additionally, structural connectivity of brain areas that demonstrated the strongest association with somatosensory symptoms was determined, using probabilistic fiber tracking based on diffusion tensor imaging data from a healthy age-matched sample. Voxels with a significant association to somatosensory deficits were clustered in two core brain regions: the central parietal white matter, also referred to as the sensory component of the superior thalamic radiation, and the parietal operculum close to the insular cortex, representing the secondary somatosensory cortex. Our objective recordings confirmed findings from clinical assessments. Probabilistic tracking connected the first region to thalamus, internal capsule, brain stem, postcentral gyrus, cerebellum, and frontal pathways, while the second region demonstrated structural connections to thalamus, insular and primary somatosensory cortex. This study reveals that stroke lesions in the sensory fibers of the superior thalamocortical radiation and the parietal operculum are significantly associated with multiple exteroceptive and proprioceptive deficits in the arm and hand. PMID:26900565

  15. Preliminary application of voxel-based morphometry technique on brain changes in neuromyelitis

    International Nuclear Information System (INIS)

    Objective: To investigate the changes of brain volumes in neuromyelitis optica (NMO) patients using voxel-based morphometry (VBM) method, and preliminarily explore the pattern of cerebral anatomical impairment. Methods: Twenty-three clinically defined NMO patients and 15 gender and age matched healthy volunteers underwent 3-dimensional (3D) fast spoiled gradient echo (FSPGR) sequence scanning on 3.0 Tesla MR system. Raw data was processed and analyzed using statistical parametric mapping (SPM) 5. Whole brain volumes included grey matter volume (GMV), white matter volume (WMV), total intracranial volume (TIV), grey matter fraction (GMF), white matter fraction (WMF), brain tissue fraction (BTF) and regional brain volumes between the two groups were compared by independent samples t-test and an Pearson were performed to compare the regional brain volumes and the ages. Results: GMV of NMO group [(610.2±55.0) ml] was significantly decreased comparing to healthy control group [(657.2±36.3) ml] (t=-2.915, P<0.05). The age of NMO patients [(40±9) years old] showed negative correlation with GMF [(42.5±2.6) %] (r=-0.673, P<0.05). Regional brain volume analysis showed decreased GMV in left insula and bilateral posterior cingutates in NMO patients, while decreased WMV was found in left frontal and left parietal white matter. Conclusion: VBM could detect brain volume changes sensitively. Total grey matter volume in NMO patients was decreased comparing to HC group. Regional grey matter atrophy in NMO patients occurred in left insular and bilateral posterior cingutates, regional white matter atrophy occurred in left frontal and left parietal lobe. (authors)

  16. Voxel based morphometry of FLAIR MRI in children with intractable focal epilepsy: Implications for surgical intervention

    International Nuclear Information System (INIS)

    Purpose: Magnetic resonance imaging (MRI), in particular fluid-attenuated inversion-recovery (FLAIR), has transformed the delineation of structural brain pathology associated with focal epilepsy. However, to date there is no literature on voxel based morphometry (VBM) of FLAIR in children with epilepsy. The aim of this study was to explore the role of visual and VBM assessment of FLAIR in pre-operative investigation of children with intractable focal epilepsy. Methods: Children with intractable epilepsy due to focal cortical dysplasia (FCD) and children with intractable cryptogenic focal epilepsy (CFE) were investigated. FLAIR and T1-weighted MRI were acquired on a 1.5T MRI scanner (Siemens, Erlangen, Germany). VBM was performed using SPM5 (Wellcome Institute of Cognitive Neuroscience, London). Results: Eight children with FCD (M = 5, age 7.9–17.3 years) and 14 children with CFE (M = 8, 7.8–16.8 years) were enrolled. VBM of FLAIR detected 7/8 (88%) of FCD whilst VBM of T1-weighted MRI detected only 3/8 (38%) FCD. VBM of FLAIR detected abnormality in 4/14 children with CFE, in 2/14 (14%) the abnormality was concordant with other data on the epileptogenic zone and with visible abnormality on repeat visual inspection of MR data. VBM of T1-weighed MRI detected abnormality in 2/14 children with CFE, none of which correlated with visible abnormality. Discussion: This study highlights the important role that FLAIR imaging has in the pre-operative assessment of children with intractable epilepsy. VBM of FLAIR may provide important information allowing selection of children with intractable CFE who are likely to benefit from further neuroradiological or neurophysiological evaluation.

  17. Brain structure in post-traumatic stress disorder A voxel-based morphometry analysis**

    Institute of Scientific and Technical Information of China (English)

    Liwen Tan; Li Zhang; Rongfeng Qi; Guangming Lu; Lingjiang Li; Jun Liu; Weihui Li

    2013-01-01

    This study compared the difference in brain structure in 12 mine disaster survivors with chronic post-traumatic stress disorder, 7 cases of improved post-traumatic stress disorder symptoms, and 14 controls who experienced the same mine disaster but did not suffer post-traumatic stress disorder, us-ing the voxel-based morphometry method. The correlation between differences in brain structure and post-traumatic stress disorder symptoms was also investigated. Results showed that the gray matter volume was the highest in the trauma control group, fol owed by the symptoms-improved group, and the lowest in the chronic post-traumatic stress disorder group. Compared with the symptoms-improved group, the gray matter volume in the lingual gyrus of the right occipital lobe was reduced in the chronic post-traumatic stress disorder group. Compared with the trauma control group, the gray matter volume in the right middle occipital gyrus and left middle frontal gyrus was reduced in the symptoms-improved group. Compared with the trauma control group, the gray matter volume in the left superior parietal lobule and right superior frontal gyrus was reduced in the chronic post-traumatic stress disorder group. The gray matter volume in the left superior parietal lobule was significantly positively correlated with the State-Trait Anxiety Inventory subscale score in the symptoms-improved group and chronic post-traumatic stress disorder group (r = 0.477, P = 0.039). Our findings indicate that (1) chronic post-traumatic stress disorder patients have gray matter structural damage in the prefrontal lobe, occip-ital lobe, and parietal lobe, (2) after post-traumatic stress, the disorder symptoms are improved and gray matter structural damage is reduced, but cannot recover to the trauma-control level, and (3) the superior parietal lobule is possibly associated with chronic post-traumatic stress disorder. Post-traumatic stress disorder patients exhibit gray matter abnormalities.

  18. Neuroanatomical circuitry associated with exploratory eye movement in schizophrenia: a voxel-based morphometric study.

    Directory of Open Access Journals (Sweden)

    Linlin Qiu

    Full Text Available Schizophrenic patients present abnormalities in a variety of eye movement tasks. Exploratory eye movement (EEM dysfunction appears to be particularly specific to schizophrenia. However, the underlying mechanisms of EEM dysfunction in schizophrenia are not clearly understood. To assess the potential neuroanatomical substrates of EEM, we recorded EEM performance and conducted a voxel-based morphometric analysis of gray matter in 33 schizophrenic patients and 29 well matched healthy controls. In schizophrenic patients, decreased responsive search score (RSS and widespread gray matter density (GMD reductions were observed. Moreover, the RSS was positively correlated with GMD in distributed brain regions in schizophrenic patients. Furthermore, in schizophrenic patients, some brain regions with neuroanatomical deficits overlapped with some ones associated with RSS. These brain regions constituted an occipito-tempro-frontal circuitry involved in visual information processing and eye movement control, including the left calcarine cortex [Brodmann area (BA 17], the left cuneus (BA 18, the left superior occipital cortex (BA 18/19, the left superior frontal gyrus (BA 6, the left cerebellum, the right lingual cortex (BA 17/18, the right middle occipital cortex (BA19, the right inferior temporal cortex (BA 37, the right dorsolateral prefrontal cortex (BA 46 and bilateral precentral gyri (BA 6 extending to the frontal eye fields (FEF, BA 8. To our knowledge, we firstly reported empirical evidence that gray matter loss in the occipito-tempro-frontal neuroanatomical circuitry of visual processing system was associated with EEM performance in schizophrenia, which may be helpful for the future effort to reveal the underlying neural mechanisms for EEM disturbances in schizophrenia.

  19. A Voxel-Based Morphometric MRI Study in Young Adults with Borderline Personality Disorder.

    Directory of Open Access Journals (Sweden)

    Xinhu Jin

    Full Text Available Increasing evidence has documented subtle changes in brain morphology and function in patients with borderline personality disorder (BPD. However, results of magnetic resonance imaging volumetry in patients with BPD are inconsistent. In addition, few researchers using voxel-based morphometry (VBM have focused on attachment and childhood trauma in BPD. This preliminary study was performed to investigate structural brain changes and their relationships to attachment and childhood trauma in a homogenous sample of young adults with BPD.We examined 34 young adults with BPD and 34 healthy controls (HCs to assess regionally specific differences in gray matter volume (GMV and gray matter concentration (GMC. Multiple regressions between brain volumes measured by VBM and attachment style questionnaire (ASQ and childhood trauma questionnaire (CTQ scores were performed.Compared with HCs, subjects with BPD showed significant bilateral increases in GMV in the middle cingulate cortex (MCC/posterior cingulate cortex (PCC/precuneus. GMC did not differ significantly between groups. In multiple regression models, ASQ insecure attachment scores were correlated negatively with GMV in the precuneus/MCC and middle occipital gyrus in HCs, HCs with more severe insecure attachment showed smaller volumes in precuneus/MCC and middle occipital gyrus, whereas no negative correlations between insecure attachment and GMV in any region were found in BPD group. In addition, CTQ total scores were not correlated with GMV in any region in the two groups respectively.Our findings fit with those of previous reports of larger precuneus GMV in patients with BPD, and suggest that GMV in the precuneus/MCC and middle occipital gyrus is associated inversely with insecure attachment style in HCs. Our finding of increased GMV in the MCC and PCC in patients with BPD compared with HCs has not been reported in previous VBM studies.

  20. Voxel Based Analysis of Surgical Revascularization for Moyamoya Disease: Pre- and Postoperative SPECT Studies.

    Science.gov (United States)

    Fushimi, Yasutaka; Okada, Tomohisa; Takagi, Yasushi; Funaki, Takeshi; Takahashi, Jun C; Miyamoto, Susumu; Togashi, Kaori

    2016-01-01

    Moyamoya disease (MMD) is a chronic, progressive, cerebrovascular occlusive disease that causes abnormal enlargement of collateral pathways (moyamoya vessels) in the region of the basal ganglia and thalamus. Cerebral revascularization procedures remain the preferred treatment for patients with MMD, improving the compromised cerebral blood flow (CBF). However, voxel based analysis (VBA) of revascularization surgery for MMD based on data from pre- and postoperative data has not been established. The latest algorithm called as Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) has been introduced for VBA as the function of statistical parametric mapping (SPM8), and improved registration has been achieved by SPM8 with DARTEL. In this study, VBA was conducted to evaluate pre- and postoperative single photon emission computed tomography (SPECT) images for MMD by SPM8 with DARTEL algorithm, and the results were compared with those from SPM8 without DARTEL (a conventional method). Thirty-two patients with MMD who underwent superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery as the first surgery were included and all patients underwent pre- and postoperative 3D T1-weighted imaging and SPECT. Pre- and postoperative SPECT images were registered to 3D T1-weighted images, then VBA was conducted. Postoperative SPECT showed more statistically increased CBF areas in the bypassed side cerebral hemisphere by using SPM8 with DARTEL (58,989 voxels; P<0.001), and increased ratio of CBF after operation was less than 15%. Meanwhile, postoperative SPECT showed less CBF increased areas by SPM8 without DARTEL. In conclusion, VBA was conducted for patients with MMD, and SPM8 with DARTEL revealed that postoperative SPECT showed statistically significant CBF increases over a relatively large area and with at most 15% increase ratio. PMID:26867219

  1. Regional grey matter structure differences between transsexuals and healthy controls--a voxel based morphometry study.

    Directory of Open Access Journals (Sweden)

    Lajos Simon

    Full Text Available Gender identity disorder (GID refers to transsexual individuals who feel that their assigned biological gender is incongruent with their gender identity and this cannot be explained by any physical intersex condition. There is growing scientific interest in the last decades in studying the neuroanatomy and brain functions of transsexual individuals to better understand both the neuroanatomical features of transsexualism and the background of gender identity. So far, results are inconclusive but in general, transsexualism has been associated with a distinct neuroanatomical pattern. Studies mainly focused on male to female (MTF transsexuals and there is scarcity of data acquired on female to male (FTM transsexuals. Thus, our aim was to analyze structural MRI data with voxel based morphometry (VBM obtained from both FTM and MTF transsexuals (n = 17 and compare them to the data of 18 age matched healthy control subjects (both males and females. We found differences in the regional grey matter (GM structure of transsexual compared with control subjects, independent from their biological gender, in the cerebellum, the left angular gyrus and in the left inferior parietal lobule. Additionally, our findings showed that in several brain areas, regarding their GM volume, transsexual subjects did not differ significantly from controls sharing their gender identity but were different from those sharing their biological gender (areas in the left and right precentral gyri, the left postcentral gyrus, the left posterior cingulate, precuneus and calcarinus, the right cuneus, the right fusiform, lingual, middle and inferior occipital, and inferior temporal gyri. These results support the notion that structural brain differences exist between transsexual and healthy control subjects and that majority of these structural differences are dependent on the biological gender.

  2. A voxel-based investigation for MRI-only radiotherapy of the brain using ultra short echo times

    DEFF Research Database (Denmark)

    Edmund, Jens Morgenthaler; Kjer, Hans Martin; Van Leemput, Koen;

    2014-01-01

    receiving cranial irradiation, each containing a co-registered MRI and CT scan, were included. An ultra short echo time MRI sequence for bone visualization was used. Six methods were investigated for three popular types of voxel-based approaches; (1) threshold-based segmentation, (2) Bayesian segmentation...... and (3) statistical regression. Each approach contained two methods. Approach 1 used bulk density assignment of MRI voxels into air, soft tissue and bone based on logical masks and the transverse relaxation time T2 of the bone. Approach 2 used similar bulk density assignments with Bayesian statistics......, however, need to be assigned to the MRI images for dose calculation and patient setup based on digitally reconstructed radiographs (DRRs). Here, we investigate the geometric and dosimetric performance for a number of popular voxel-based methods to generate a so-called pseudo CT (pCT). Five patients...

  3. A Voxel-Based Morphometry Study of the Brain of University Students Majoring in Music and Nonmusic Disciplines

    OpenAIRE

    2015-01-01

    The brain changes flexibly due to various experiences during the developmental stages of life. Previous voxel-based morphometry (VBM) studies have shown volumetric differences between musicians and nonmusicians in several brain regions including the superior temporal gyrus, sensorimotor areas, and superior parietal cortex. However, the reported brain regions depend on the study and are not necessarily consistent. By VBM, we investigated the effect of musical training on the brain structure by...

  4. Cortical neuronal loss and hippocampal sclerosis are not detected by voxel-based morphometry in individual epilepsy surgery patients

    OpenAIRE

    Eriksson, S. H.; Thom, M; Symms, M.R.; N.K. Focke; Martinian, L.; Sisodiya, S M; Duncan, J.S.

    2009-01-01

    Voxel-based morphometry (VBM) has detected differences between brains of groups of patients with epilepsy and controls, but the sensitivity for detecting subtle pathological changes in single subjects has not been established. The aim of the study was to test the sensitivity of VBM using statistical parametric niapping (SPM5) to detect hippocampal sclerosis (HS) and cortical neuronal loss in individual patients. T1-weighted volumetric 1.5 T MR images from 13 patients with HS and laminar corti...

  5. Relationship between Personality and Gray Matter Volume in Healthy Young Adults: A Voxel-Based Morphometric Study

    OpenAIRE

    Lu, Fengmei; Huo, Yajun; Meiling LI; Chen, Heng; LIU Feng; Wang, Yifeng; Long, Zhiliang; Duan, Xujun; Zhang, Jiang; Zeng, Ling; Chen, Huafu

    2014-01-01

    This study aims to investigate the neurostructural foundations of the human personality in young adults. High-resolution structural T1-weighted MR images of 71 healthy young individuals were processed using voxel-based morphometric (VBM) approach. Multiple regression analyses were performed to identify the associations between personality traits and gray matter volume (GMV). The Eysenck Personality Questionnaire-Revised, Short Scale for Chinese was chosen to assess the personality traits. Thi...

  6. Correlation between voxel based morphometry and manual volumetry in magnetic resonance images of the human brain

    Directory of Open Access Journals (Sweden)

    Ricardo R. Uchida

    2008-03-01

    Full Text Available This is a comparative study between manual volumetry (MV and voxel based morphometry (VBM as methods of evaluating the volume of brain structures in magnetic resonance images. The volumes of the hippocampus and the amygdala of 16 panic disorder patients and 16 healthy controls measured through MV were correlated with the volumes of gray matter estimated by optimized modulated VBM. The chosen structures are composed almost exclusively of gray matter. Using a 4 mm Gaussian filter, statistically significant clusters were found bilaterally in the hippocampus and in the right amygdala in the statistical parametric map correlating with the respective manual volume. With the conventional 12 mm filter,a significant correlation was found only for the right hippocampus. Therefore,narrowfilters increase the sensitivity of the correlation procedure, especially when small brain structures are analyzed. The two techniques seem to consistently measure structural volume.Trata-se de estudo comparativo entre a volumetria manual(VM e a morfometria baseada no vóxel (MBV, como métodos de avaliação do volume de estruturas cerebrais. Os volumes do hipocampo e da amídala de 16 pacientes de pânico e 16 controles sadios medidos através da VM foram correlacionados com os volumes de matéria cinzenta estimados pela MBV.As estruturas escolhidas são constituídas quase exclusivamente de matéria cinzenta. Utilizando um filtro Gaussiano de 4 mm, encontram-se, bilateralmente, aglomerados significativos de correlação nas duas estruturas no mapa estatístico paramétrico, correspondendo ao respectivo volume manual. Com o filtro convencional de 12 mm, apenas uma correlação significativa foi encontrada no hipocampo direito. Portanto, filtros estreitos aumentam a sensibilidade do procedimento de correlação,especialmente quando estruturas pequenas são analisadas. Ambas as técnicas parecem medir consistentemente o volume estrutural.

  7. Voxel-based classification of FDG PET in dementia using inter-scanner normalization.

    Science.gov (United States)

    Thiele, Frank; Young, Stewart; Buchert, Ralph; Wenzel, Fabian

    2013-08-15

    Statistical mapping of FDG PET brain images has become a common tool in differential diagnosis of patients with dementia. We present a voxel-based classification system of neurodegenerative dementias based on partial least squares (PLS). Such a classifier relies on image databases of normal controls and dementia cases as training data. Variations in PET image characteristics can be expected between databases, for example due to differences in instrumentation, patient preparation, and image reconstruction. This study evaluates (i) the impact of databases from different scanners on classification accuracy and (ii) a method to improve inter-scanner classification. Brain FDG PET databases from three scanners (A, B, C) at two clinical sites were evaluated. Diagnostic categories included normal controls (NC, nA=26, nB=20, nC=24 for each scanner respectively), Alzheimer's disease (AD, nA=44, nB=11, nC=16), and frontotemporal dementia (FTD, nA=13, nB=13, nC=5). Spatially normalized images were classified as NC, AD, or FTD using partial least squares. Supervised learning was employed to determine classifier parameters, whereby available data is sub-divided into training and test sets. Four different database setups were evaluated: (i) "in-scanner": training and test data from the same scanner, (ii) "x-scanner": training and test data from different scanners, (iii) "train other": train on both x-scanners, and (iv) "train all": train on all scanners. In order to moderate the impact of inter-scanner variations on image evaluation, voxel-by-voxel scaling was applied based on "ratio images". Good classification accuracy of on average 94% was achieved for the in-scanner setups. Accuracy deteriorated for setups with mismatched scanners (79-91%). Ratio-image normalization improved all results with mismatched scanners (85-92%). In conclusion, automatic classification of individual FDG PET in differential diagnosis of dementia is feasible. Accuracy can vary with respect to scanner or

  8. Voxel-based morphometry in epileptic baboons: Parallels to human juvenile myoclonic epilepsy.

    Science.gov (United States)

    Szabó, C Ákos; Salinas, Felipe S

    2016-08-01

    The epileptic baboon represents a natural model for genetic generalized epilepsy (GGE), closely resembling juvenile myoclonic epilepsy (JME). Due to functional neuroimaging and pathological differences between epileptic (SZ+) and asymptomatic control (CTL) baboons, we expected structural differences in gray matter concentration (GMC) using voxel-based morphometry (VBM). Standard anatomical (MP-RAGE) MRI scans using a 3T Siemens TIM Trio (Siemens, Erlangen, Germany) were available in 107 baboons (67 females; mean age 16±6years) with documented clinical histories and scalp-electroencephalography (EEG) results. For neuroimaging, baboons were anesthetized with isoflurane 1% (1-1.5 MAC) and paralyzed with vecuronium (0.1-0.3mg/kg). Data processing and analysis were performed using FSL's VBM toolbox. GMC was compared between CTL and SZ+ baboons, epileptic baboons with interictal epileptic discharges on scalp EEG (SZ+/IED+), asymptomatic baboons with abnormal EEGs (SZ-/IED+), and IED+ baboons with (IED+/PS+) and without (IED+/PS-) photosensitivity, and the subgroups amongst themselves. Age and gender related changes in gray matter volumes were also included as confound regressors in the VBM analyses of each animal group. Significant increases in GMC were noted in the SZ+/IED+ subgroup compared to the CTL group, including bilaterally in the frontopolar, orbitofrontal and anterolateral temporal cortices, while decreases in GMC were noted in the right more than left primary visual cortices and in the specific nuclei of the thalamus, including reticular, anterior and medial dorsal nuclei. No significant differences were noted otherwise, except that SZ+/IED+ baboons demonstrated increased GMC in the globus pallidae bilaterally compared to the SZ-/IED+ group. Similar to human studies of JME, the epileptic baboons demonstrated GMC decreases in the thalami and occipital cortices, suggesting secondary injury due to chronic epilepsy. Cortical GMC, on the other hand, was increased

  9. Do we need a voxel-based approach for LiDAR data in geomorphology?

    Science.gov (United States)

    Székely, Balázs; Dorninger, Peter; Faber, Robert; Nothegger, Clemens

    2010-05-01

    to store, process and visualize the results. To reduce the amount of originally collected data for further applications, in general, continuous model surfaces are derived from the point clouds using interpolation approaches. Commonly, grid-based or triangulation models are used for that purpose. Typical models are Digital Surface Models (DSM) representing the whole topography including all natural (e.g. vegetation) and artificial (e.g. buildings) objects and Digital Terrain Models (DTM) representing the topography only. In the visual computing industry the voxel-based approach is quite common for various purposes. Although this technology is quite straightforward concerning the data reduction, it is hardly applied in the geomorphic context. An argument can be against its application that mostly we are interested in a surface, not a volume. Of course in the strict sense it is true, however, if we consider the technology itself how the data, especially the ground data are derived, it turns out that actually it is a volume with a certain accuracy that we are sampling of. The position of this "relatively thin" volume also varies, especially in mountainous areas. Here, depending on the slope angles, the accuracy also varies, especially for the integrated data set consisting of a multitude of sources, e.g. mixing conventional (first echo/last echo) and full-waveform data. These point clouds also contain attributes that otherwise could be very valuable, but during the integration, their meaning may be lost, or it cannot be integrated to the data set. A large scale application of such approaches is mainly prevented by the problems introduced by the high amount of data, making on-the-fly processing a challenging task. To overcome these restrictions and to enable taking advantage of the new possibilities provided by the waveform analysis, we propose a voxel-based data representation approach. The multichannel/multilayer design with an a priori unlimited number of layers

  10. A voxel based comparative analysis using magnetization transfer imaging and T1-weighted magnetic resonance imaging in progressive supranuclear palsy

    Directory of Open Access Journals (Sweden)

    Mangalore Sandhya

    2014-01-01

    Full Text Available Aims: In progressive supranuclear palsy (PSP tissue damage occurs in specific cortical and subcortical regions. Voxel based analysis using T1-weighted images depict quantitative gray matter (GM atrophy changes. Magnetization transfer (MT imaging depicts qualitative changes in the brain parenchyma. The purpose of our study was to investigate whether MT imaging could indicate abnormalities in PSP. Settings and Design: A total of 10 patients with PSP (9 men and 1 woman and 8 controls (5 men and 3 women were studied with T1-weighted magnetic resonance imaging (MRI and 3DMT imaging. Voxel based analysis of T1-weighted MRI was performed to investigate brain atrophy while MT was used to study qualitative abnormalities in the brain tissue. We used SPM8 to investigate group differences (with two sample t-test using the GM and white matter (WM segmented data. Results: T1-weighted imaging and MT are equally sensitive to detect changes in GM and WM in PSP. Magnetization transfer ratio images and magnetization-prepared rapid acquisition of gradient echo revealed extensive bilateral volume and qualitative changes in the orbitofrontal, prefrontal cortex and limbic lobe and sub cortical GM. The prefrontal structures involved were the rectal gyrus, medial, inferior frontal gyrus (IFG and middle frontal gyrus (MFG. The anterior cingulate, cingulate gyrus and lingual gyrus of limbic lobe and subcortical structures such as caudate, thalamus, insula and claustrum were also involved. Cerebellar involvement mainly of anterior lobe was also noted. Conclusions: The findings suggest that voxel based MT imaging permits a whole brain unbiased investigation of central nervous system structural integrity in PSP.

  11. Neurofunctional maps of the 'maternal brain' and the effects of oxytocin: a multimodal voxel-based meta-analysis.

    Science.gov (United States)

    Rocchetti, Matteo; Radua, Joaquim; Paloyelis, Yannis; Xenaki, Lida-Alkisti; Frascarelli, Marianna; Caverzasi, Edgardo; Politi, Pierluigi; Fusar-Poli, Paolo

    2014-10-01

    Several studies have tried to understand the possible neurobiological basis of mothering. The putative involvement of oxytocin, in this regard, has been deeply investigated. Performing a voxel-based meta-analysis, we aimed at testing the hypothesis of overlapping brain activation in functional magnetic resonance imaging (fMRI) studies investigating the mother-infant interaction and the oxytocin modulation of emotional stimuli in humans. We performed two systematic literature searches: fMRI studies investigating the neurofunctional correlates of the 'maternal brain' by employing mother-infant paradigms; and fMRI studies employing oxytocin during emotional tasks. A unimodal voxel-based meta-analysis was performed on each database, whereas a multimodal voxel-based meta-analytical tool was adopted to assess the hypothesis that the neurofunctional effects of oxytocin are detected in brain areas implicated in the 'maternal brain.' We found greater activation in the bilateral insula extending to the inferior frontal gyrus, basal ganglia and thalamus during mother-infant interaction and greater left insular activation associated with oxytocin administration versus placebo. Left insula extending to basal ganglia and frontotemporal gyri as well as bilateral thalamus and amygdala showed consistent activation across the two paradigms. Right insula also showed activation across the two paradigms, and dorsomedial frontal cortex activation in mothers but deactivation with oxytocin. Significant activation in areas involved in empathy, emotion regulation, motivation, social cognition and theory of mind emerged from our multimodal meta-analysis, supporting the need for further studies directly investigating the neurobiology of oxytocin in the mother-infant relationship. PMID:24734987

  12. Decreased gray matter volume is associated with the subtypes of psychotic symptoms in patients with antipsychotic-naïve mild or moderate Alzheimer's disease: A voxel-based morphometry study.

    Science.gov (United States)

    Lee, Young-Min; Chung, Young-In; Park, Je-Min; Lee, Byung-Dae; Moon, Eunsoo; Jeong, Hee-Jeong; Kim, Ji-Hoon; Kim, Hak-Jin; Mun, Chi-Woong; Kim, Tae-Hyung; Kim, Young-Hoon; Kim, Eun-Joo

    2016-03-30

    The purpose of this study was to investigate the association between brain regional gray matter volume and two subtypes of psychotic symptoms, namely paranoid and misidentification subtypes, in antipsychotic-naïve mild or moderate Alzheimer's disease (AD) patients. Forty AD patients with psychotic symptoms and 25 AD patients without psychotic symptoms were assessed for cognitive and functional impairment. Presence and subtype of psychotic symptoms were assessed by using the delusion and hallucination subscale of the Korean Neuropsychiatric Inventory (K-NPI). Structural MRI images were acquired on a 3 T scanner, and were analyzed using voxel-based morphometry (VBM) for automated analysis. The misidentification subtype is associated with more severe gray matter atrophy, and paranoid subtype is associated with less severe gray matter atrophy compared to non-psychosis group. These results suggest that the misidentification, the paranoid subtype and the non-psychosis group have a distinct neural correlation. PMID:27000306

  13. An optimized voxel-based morphometry MRI study of the brain in patients with first episode schizophrenia

    International Nuclear Information System (INIS)

    Objective: To evaluate the structural differences between patients with first episode schizophrenia and normal controls using optimized voxel-based morphometry (VBM) study. Methods: High resolution T1 weighted images were obtained using 3.0 T MR from 13 first-episode, untreated schizophrenia and 13 age, sex, handedness matched normal controls. Images were preprocessed by employing the optimized VBM and two sample t-test was used to detect differences between patients and normal controls with respect to both density and volume of gray matter in the brain. Results Patients with schizophrenia had significant lower gray matter density and gray matter volume generally distributed among bilateral hemispheres, especially in bilateral frontal and temporal lobes. However, no significant increase of gray matter density and gray matter volume was observed in these patients. Conclusions: Optimized voxel-based morphometry study is an automatic and effective method to study psychological diseases such as schizophrenia. Compared with normal controls, patients with schizophrenia had significantly lower gray matter density and gray matter volume across the bilateral hemispheres. (authors)

  14. The neuronal correlates of digits backward are revealed by voxel-based morphometry and resting-state functional connectivity analyses.

    Directory of Open Access Journals (Sweden)

    Rui Li

    Full Text Available Digits backward (DB is a widely used neuropsychological measure that is believed to be a simple and effective index of the capacity of the verbal working memory. However, its neural correlates remain elusive. The aim of this study is to investigate the neural correlates of DB in 299 healthy young adults by combining voxel-based morphometry (VBM and resting-state functional connectivity (rsFC analyses. The VBM analysis showed positive correlations between the DB scores and the gray matter volumes in the right anterior superior temporal gyrus (STG, the right posterior STG, the left inferior frontal gyrus and the left Rolandic operculum, which are four critical areas in the auditory phonological loop of the verbal working memory. Voxel-based correlation analysis was then performed between the positive rsFCs of these four clusters and the DB scores. We found that the DB scores were positively correlated with the rsFCs within the salience network (SN, that is, between the right anterior STG, the dorsal anterior cingulate cortex and the right fronto-insular cortex. We also found that the DB scores were negatively correlated with the rsFC within an anti-correlation network of the SN, between the right posterior STG and the left posterior insula. Our findings suggest that DB performance is related to the structural and functional organizations of the brain areas that are involved in the auditory phonological loop and the SN.

  15. Larger right posterior parietal volume in action video game experts: a behavioral and voxel-based morphometry (VBM study.

    Directory of Open Access Journals (Sweden)

    Satoshi Tanaka

    Full Text Available Recent studies suggest that action video game players exhibit superior performance in visuospatial cognitive tasks compared with non-game players. However, the neural basis underlying this visuospatial cognitive performance advantage remains largely unknown. The present human behavioral and imaging study compared gray matter volume in action video game experts and non-experts using structural magnetic resonance imaging and voxel-based morphometry analysis. The results revealed significantly larger gray matter volume in the right posterior parietal cortex in experts compared with non-experts. Furthermore, the larger gray matter volume in the right posterior parietal cortex significantly correlated with individual performance in a visual working memory task in experts. These results suggest that differences in brain structure may be linked to extensive video game play, leading to superior visuospatial cognitive performance in action video game experts.

  16. Voxel-based comparison of whole brain gray matter of patients with mild Alzheimer's disease with normal aging volunteers

    International Nuclear Information System (INIS)

    Objective: To detect gray matter abnormalities of whole brain in patients with mild Alzheimer's disease (AD) by voxel-based morphometry (VBM). Methods: Thirteen patients with mild Alzheimer's disease and sixteen normal aging volunteers underwent 3D SPGR scanning. For every subject, data was transferred to PC to be normalized, segmented and smoothed using SPM99. Non-dependent samples T-tests were conducted to compare gray matter' density voxel to voxel between the two groups. Results Significant reductions in gray matter density were found in the bilateral hippocampi and nucleus amygdalae, bilateral insulae, bilateral medial thalami, bilateral rectus gyri, right superior temporal gyms, right caudate nucleus, fight prefrontal lobe, right basal forebrain and portions of right occipital lobe. Conclusion: VBM reveals significant gray matter' reductions of numeral cortices in mild Alzheimer's disease. It can be a useful method to evaluate the anatomical changes in the progress of the disease. (authors)

  17. Larger right posterior parietal volume in action video game experts: a behavioral and voxel-based morphometry (VBM) study.

    Science.gov (United States)

    Tanaka, Satoshi; Ikeda, Hanako; Kasahara, Kazumi; Kato, Ryo; Tsubomi, Hiroyuki; Sugawara, Sho K; Mori, Makoto; Hanakawa, Takashi; Sadato, Norihiro; Honda, Manabu; Watanabe, Katsumi

    2013-01-01

    Recent studies suggest that action video game players exhibit superior performance in visuospatial cognitive tasks compared with non-game players. However, the neural basis underlying this visuospatial cognitive performance advantage remains largely unknown. The present human behavioral and imaging study compared gray matter volume in action video game experts and non-experts using structural magnetic resonance imaging and voxel-based morphometry analysis. The results revealed significantly larger gray matter volume in the right posterior parietal cortex in experts compared with non-experts. Furthermore, the larger gray matter volume in the right posterior parietal cortex significantly correlated with individual performance in a visual working memory task in experts. These results suggest that differences in brain structure may be linked to extensive video game play, leading to superior visuospatial cognitive performance in action video game experts. PMID:23776706

  18. Assessment of memory/attention impairment in children with primary nocturnal enuresis: A voxel-based morphometry study

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Bing, E-mail: yubing@sj-hospital.org [Department of Radiology, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Kong, Fanxing, E-mail: kongfx@sj-hospital.org [Department of Radiology, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Peng, Miao, E-mail: pengm@sj-hospital.org [Psychological Outpatient Service, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Ma, Hongwei, E-mail: mahongwei1960@hotmail.com [Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Liu, Na, E-mail: liuna.916@163.com [Department of Radiology, the People' s Hospital of Liaoning Province, Shenyang 110016 (China); Guo, Qiyong, E-mail: guoqy@sj-hospital.org [Department of Radiology, Shengjing Hospital of China Medical University, Shenyang 110004 (China)

    2012-12-15

    Aim: Assessment of memory/attention impairment and related exploration of the gray matter differential MR density variations between children with and without primary nocturnal enuresis (PNE) using voxel-based morphometry (VBM) methodology is the aim of the present study. Methods: A total of 75 right-handed PNE children (M/F = 39:36, average age 10.4 ± 1.3 years) and 72 age-matched, right-handed, healthy controls (M/F = 40:32, 10.0 ± 1.2 years) were recruited for the study. First, intelligence tests were performed using the China-Wechsler Intelligence Scale for Children (C-WISC) in both PNE and control children. The full intelligence quotient (FIQ), verbal IQ (VIQ), performance IQ (PIQ), and memory/caution (M/C) factor were measured. Voxel-based morphometry (VBM) was performed using high resolution 3 Tesla T1-weighted MR images, processed using VBM5 in the PNE and control children. Student's t-test or Mann–Whitney U test were performed to analyze the difference in the gray matter density (GMD) between the PNE and control children. Results: The FIQ, VIQ, and PIQ in the PNE group were within the normal range and did not significantly differ from the control group, though the M/C factor was statistically lower in the PNE group. Compared with normal controls, PNE children exhibited lower GMD in the right dorsolateral prefrontal cortex (DLPFC) and the left cerebellum (P < 0.001). Conclusion: Impairment in memory/attention was detected in PNE children, and the structural abnormalities of the right DLPFC and left cerebellum are likely to be implicated in these deficits.

  19. Permutation and parametric tests for effect sizes in voxel-based morphometry of gray matter volume in brain structural MRI.

    Science.gov (United States)

    Dickie, David A; Mikhael, Shadia; Job, Dominic E; Wardlaw, Joanna M; Laidlaw, David H; Bastin, Mark E

    2015-12-01

    Permutation testing has been widely implemented in voxel-based morphometry (VBM) tools. However, this type of non-parametric inference has yet to be thoroughly compared with traditional parametric inference in VBM studies of brain structure. Here we compare both types of inference and investigate what influence the number of permutations in permutation testing has on results in an exemplar study of how gray matter proportion changes with age in a group of working age adults. High resolution T1-weighted volume scans were acquired from 80 healthy adults aged 25-64years. Using a validated VBM procedure and voxel-based permutation testing for Pearson product-moment coefficient, the effect sizes of changes in gray matter proportion with age were assessed using traditional parametric and permutation testing inference with 100, 500, 1000, 5000, 10000 and 20000 permutations. The statistical significance was set at PPFDR<0.05) declines in gray matter proportion with age identified with permutation testing inference (N≈6000) were approximately twice the size of those identified with parametric inference (N=3221voxels). Permutation testing with 10000 (N=6251voxels) and 20000 (N=6233voxels) permutations produced clusters that were generally consistent with each other. However, with 1000 permutations there were approximately 20% more statistically significant voxels (N=7117voxels) than with ≥10000 permutations. Permutation testing inference may provide a more sensitive method than traditional parametric inference for identifying age-related differences in gray matter proportion. Based on the results reported here, at least 10000 permutations should be used in future univariate VBM studies investigating age related changes in gray matter to avoid potential false findings. Additional studies using permutation testing in large imaging databanks are required to address the impact of model complexity, multivariate analysis, number of observations, sampling bias and data quality

  20. Assessment of memory/attention impairment in children with primary nocturnal enuresis: A voxel-based morphometry study

    International Nuclear Information System (INIS)

    Aim: Assessment of memory/attention impairment and related exploration of the gray matter differential MR density variations between children with and without primary nocturnal enuresis (PNE) using voxel-based morphometry (VBM) methodology is the aim of the present study. Methods: A total of 75 right-handed PNE children (M/F = 39:36, average age 10.4 ± 1.3 years) and 72 age-matched, right-handed, healthy controls (M/F = 40:32, 10.0 ± 1.2 years) were recruited for the study. First, intelligence tests were performed using the China-Wechsler Intelligence Scale for Children (C-WISC) in both PNE and control children. The full intelligence quotient (FIQ), verbal IQ (VIQ), performance IQ (PIQ), and memory/caution (M/C) factor were measured. Voxel-based morphometry (VBM) was performed using high resolution 3 Tesla T1-weighted MR images, processed using VBM5 in the PNE and control children. Student's t-test or Mann–Whitney U test were performed to analyze the difference in the gray matter density (GMD) between the PNE and control children. Results: The FIQ, VIQ, and PIQ in the PNE group were within the normal range and did not significantly differ from the control group, though the M/C factor was statistically lower in the PNE group. Compared with normal controls, PNE children exhibited lower GMD in the right dorsolateral prefrontal cortex (DLPFC) and the left cerebellum (P < 0.001). Conclusion: Impairment in memory/attention was detected in PNE children, and the structural abnormalities of the right DLPFC and left cerebellum are likely to be implicated in these deficits.

  1. Simplified Boardgames

    OpenAIRE

    Kowalski, Jakub; Sutowicz, Jakub; Szykuła, Marek

    2016-01-01

    We formalize Simplified Boardgames language, which describes a subclass of arbitrary board games. The language structure is based on the regular expressions, which makes the rules easily machine-processable while keeping the rules concise and fairly human-readable.

  2. Early Gray-Matter and White-Matter Concentration in Infancy Predict Later Language Skills: A Whole Brain Voxel-Based Morphometry Study

    Science.gov (United States)

    Can, Dilara Deniz; Richards, Todd; Kuhl, Patricia K.

    2013-01-01

    Magnetic Resonance Imaging (MRI) brain scans were obtained from 19 infants at 7 months. Expressive and receptive language performance was assessed at 12 months. Voxel-based morphometry (VBM) identified brain regions where gray-matter and white-matter concentrations at 7 months correlated significantly with children's language scores at 12 months.…

  3. Topographic deformation patterns of knee cartilage after exercises with high knee flexion: an in vivo 3D MRI study using voxel-based analysis at 3T

    Energy Technology Data Exchange (ETDEWEB)

    Horng, Annie; Stockinger, M.; Notohamiprodjo, M. [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); Raya, J.G. [New York University Langone Medical Center, Center for Biomedical Imaging, New York, NY (United States); Pietschmann, M. [Ludwig-Maximilians-University Hospital Munich, Department of Orthopedic Surgery, Munich (Germany); Hoehne-Hueckstaedt, U.; Glitsch, U.; Ellegast, R. [Institute for Occupational Safety and Health of the German Social Accident Insurance (IFA), Sankt Augustin (Germany); Hering, K.G. [Miner' s Hospital, Department of Diagnostic Radiology, Dortmund (Germany); Glaser, C. [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); RZM Zentrum, Munich (Germany)

    2015-06-01

    To implement a novel voxel-based technique to identify statistically significant local cartilage deformation and analyze in-vivo topographic knee cartilage deformation patterns using a voxel-based thickness map approach for high-flexion postures. Sagittal 3T 3D-T1w-FLASH-WE-sequences of 10 healthy knees were acquired before and immediately after loading (kneeling/squatting/heel sitting/knee bends). After cartilage segmentation, 3D-reconstruction and 3D-registration, colour-coded deformation maps were generated by voxel-based subtraction of loaded from unloaded datasets to visualize cartilage thickness changes in all knee compartments. Compression areas were found bifocal at the peripheral medial/caudolateral patella, both posterior femoral condyles and both anterior/central tibiae. Local cartilage thickening were found adjacent to the compression areas. Significant local strain ranged from +13 to -15 %. Changes were most pronounced after squatting, least after knee bends. Shape and location of deformation areas varied slightly with the loading paradigm, but followed a similar pattern consistent between different individuals. Voxel-based deformation maps identify individual in-vivo load-specific and posture-associated strain distribution in the articular cartilage. The data facilitate understanding individual knee loading properties and contribute to improve biomechanical 3 models. They lay a base to investigate the relationship between cartilage degeneration patterns in common osteoarthritis and areas at risk of cartilage wear due to mechanical loading in work-related activities. (orig.)

  4. Topographic deformation patterns of knee cartilage after exercises with high knee flexion: an in vivo 3D MRI study using voxel-based analysis at 3T

    International Nuclear Information System (INIS)

    To implement a novel voxel-based technique to identify statistically significant local cartilage deformation and analyze in-vivo topographic knee cartilage deformation patterns using a voxel-based thickness map approach for high-flexion postures. Sagittal 3T 3D-T1w-FLASH-WE-sequences of 10 healthy knees were acquired before and immediately after loading (kneeling/squatting/heel sitting/knee bends). After cartilage segmentation, 3D-reconstruction and 3D-registration, colour-coded deformation maps were generated by voxel-based subtraction of loaded from unloaded datasets to visualize cartilage thickness changes in all knee compartments. Compression areas were found bifocal at the peripheral medial/caudolateral patella, both posterior femoral condyles and both anterior/central tibiae. Local cartilage thickening were found adjacent to the compression areas. Significant local strain ranged from +13 to -15 %. Changes were most pronounced after squatting, least after knee bends. Shape and location of deformation areas varied slightly with the loading paradigm, but followed a similar pattern consistent between different individuals. Voxel-based deformation maps identify individual in-vivo load-specific and posture-associated strain distribution in the articular cartilage. The data facilitate understanding individual knee loading properties and contribute to improve biomechanical 3 models. They lay a base to investigate the relationship between cartilage degeneration patterns in common osteoarthritis and areas at risk of cartilage wear due to mechanical loading in work-related activities. (orig.)

  5. A voxel-based investigation for MRI-only radiotherapy of the brain using ultra short echo times

    International Nuclear Information System (INIS)

    Radiotherapy (RT) based on magnetic resonance imaging (MRI) as the only modality, so-called MRI-only RT, would remove the systematic registration error between MR and computed tomography (CT), and provide co-registered MRI for assessment of treatment response and adaptive RT. Electron densities, however, need to be assigned to the MRI images for dose calculation and patient setup based on digitally reconstructed radiographs (DRRs). Here, we investigate the geometric and dosimetric performance for a number of popular voxel-based methods to generate a so-called pseudo CT (pCT). Five patients receiving cranial irradiation, each containing a co-registered MRI and CT scan, were included. An ultra short echo time MRI sequence for bone visualization was used. Six methods were investigated for three popular types of voxel-based approaches; (1) threshold-based segmentation, (2) Bayesian segmentation and (3) statistical regression. Each approach contained two methods. Approach 1 used bulk density assignment of MRI voxels into air, soft tissue and bone based on logical masks and the transverse relaxation time T2 of the bone. Approach 2 used similar bulk density assignments with Bayesian statistics including or excluding additional spatial information. Approach 3 used a statistical regression correlating MRI voxels with their corresponding CT voxels. A similar photon and proton treatment plan was generated for a target positioned between the nasal cavity and the brainstem for all patients. The CT agreement with the pCT of each method was quantified and compared with the other methods geometrically and dosimetrically using both a number of reported metrics and introducing some novel metrics. The best geometrical agreement with CT was obtained with the statistical regression methods which performed significantly better than the threshold and Bayesian segmentation methods (excluding spatial information). All methods agreed significantly better with CT than a reference water MRI

  6. Brain structural abnormalities in behavior therapy-resistant obsessive-compulsive disorder revealed by voxel-based morphometry

    Directory of Open Access Journals (Sweden)

    Hashimoto N

    2014-10-01

    Full Text Available Nobuhiko Hashimoto,1 Shutaro Nakaaki,2 Akiko Kawaguchi,1 Junko Sato,1 Harumasa Kasai,3 Takashi Nakamae,4 Jin Narumoto,4 Jun Miyata,5 Toshi A Furukawa,6,7 Masaru Mimura2 1Department of Psychiatry and Cognitive-Behavioral Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan; 2Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan; 3Department of Central Radiology, Nagoya City University Hospital, Nagoya, Japan; 4Department of Psychiatry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan; 5Department of Psychiatry, Graduate School of Medicine, Kyoto University, Kyoto, Japan; 6Department of Health Promotion and Human Behavior, 7Department of Clinical Epidemiology, Kyoto University Graduate School of Medicine/School of Public Health, Kyoto, Japan Background: Although several functional imaging studies have demonstrated that behavior therapy (BT modifies the neural circuits involved in the pathogenesis of obsessive-compulsive disorder (OCD, the structural abnormalities underlying BT-resistant OCD remain unknown. Methods: In this study, we examined the existence of regional structural abnormalities in both the gray matter and the white matter of patients with OCD at baseline using voxel-based morphometry in responders (n=24 and nonresponders (n=15 to subsequent BT. Three-dimensional T1-weighted magnetic resonance imaging was performed before the completion of 12 weeks of BT. Results: Relative to the responders, the nonresponders exhibited significantly smaller gray matter volumes in the right ventromedial prefrontal cortex, the right orbitofrontal cortex, the right precentral gyrus, and the left anterior cingulate cortex. In addition, relative to the responders, the nonresponders exhibited significantly smaller white matter volumes in the left cingulate bundle and the left superior frontal white matter. Conclusion: These results suggest that the brain

  7. A voxel-based investigation for MRI-only radiotherapy of the brain using ultra short echo times

    Science.gov (United States)

    Edmund, Jens M.; Kjer, Hans M.; Van Leemput, Koen; Hansen, Rasmus H.; Andersen, Jon AL; Andreasen, Daniel

    2014-12-01

    Radiotherapy (RT) based on magnetic resonance imaging (MRI) as the only modality, so-called MRI-only RT, would remove the systematic registration error between MR and computed tomography (CT), and provide co-registered MRI for assessment of treatment response and adaptive RT. Electron densities, however, need to be assigned to the MRI images for dose calculation and patient setup based on digitally reconstructed radiographs (DRRs). Here, we investigate the geometric and dosimetric performance for a number of popular voxel-based methods to generate a so-called pseudo CT (pCT). Five patients receiving cranial irradiation, each containing a co-registered MRI and CT scan, were included. An ultra short echo time MRI sequence for bone visualization was used. Six methods were investigated for three popular types of voxel-based approaches; (1) threshold-based segmentation, (2) Bayesian segmentation and (3) statistical regression. Each approach contained two methods. Approach 1 used bulk density assignment of MRI voxels into air, soft tissue and bone based on logical masks and the transverse relaxation time T2 of the bone. Approach 2 used similar bulk density assignments with Bayesian statistics including or excluding additional spatial information. Approach 3 used a statistical regression correlating MRI voxels with their corresponding CT voxels. A similar photon and proton treatment plan was generated for a target positioned between the nasal cavity and the brainstem for all patients. The CT agreement with the pCT of each method was quantified and compared with the other methods geometrically and dosimetrically using both a number of reported metrics and introducing some novel metrics. The best geometrical agreement with CT was obtained with the statistical regression methods which performed significantly better than the threshold and Bayesian segmentation methods (excluding spatial information). All methods agreed significantly better with CT than a reference water MRI

  8. Voxel-based analysis of cerebral glucose metabolism in AD and non-AD degenerative dementia using statistical parametric mapping

    International Nuclear Information System (INIS)

    Objective: It is know that Alzheimer's disease (AD) and non-AD degenerative dementia have some clinical features in common. The aim of this study was to investigate the specific patterns of regional, cerebral glucose metabolism of AD and non-AD degenerative dementia patients, using a voxel-based 18F-fluorodeoxyglucose (FDG) PET study. Methods: Twenty-three AD patients and 24 non-AD degenerative dementia patients including 9 Parkinson's disease with dementia(PDD), 7 frontal-temporal dementia (FTD), 8 dementia of Lewy bodies (DLB) patients, and 40 normal controls (NC)were included in the study. To evaluate the relative cerebral metabolic rate of glucose (rCMRglc), 18F-FDG PET imaging was performed in all subjects. Subsequently, statistical comparison of PET data with NC was performed using statistical parametric mapping (SPM). Results: The AD-associated FDG imaging pattern typically presented as focal cortical hypometabolism in bilateral parietotemporal association cortes and(or) frontal lobe and the posterior cingulate gyms. As compared with the comparative NC, FTD group demonstrated significant regional reductions in rCMRglc in bilateral frontal, parietal lobes, the cingulate gyri, insulae, left precuneus, and the subcortical structures (including right putamen, right medial dorsal nucleus and ventral anterior nucleus). The PDD group showed regional reductions in rCMRglc in bilateral frontal cortexes, parietotemporal association cortexes, and the subcortical structures (including left caudate, right putamen, the dorsomedial thalamus, lateral posterior nucleus, and pulvinar). By the voxel-by-voxel comparison between the DLB group and NC group, regional reductions in rCMRglc included bilateral occipital cortexes, precuneuses, frontal and parietal lobes, left anterior cingulate gyms, right superior temporal cortex, and the subcortical structures including putamen, caudate, lateral posterior nucleus, and pulvinar. Conclusions: The rCMRglc was found to be different

  9. Voxel-based morphometry in opera singers: Increased gray-matter volume in right somatosensory and auditory cortices.

    Science.gov (United States)

    Kleber, Boris; Veit, Ralf; Moll, Christina Valérie; Gaser, Christian; Birbaumer, Niels; Lotze, Martin

    2016-06-01

    In contrast to instrumental musicians, professional singers do not train on a specific instrument but perfect a motor system that has already been extensively trained during speech motor development. Previous functional imaging studies suggest that experience with singing is associated with enhanced somatosensory-based vocal motor control. However, experience-dependent structural plasticity in vocal musicians has rarely been studied. We investigated voxel-based morphometry (VBM) in 27 professional classical singers and compared gray matter volume in regions of the "singing-network" to an age-matched group of 28 healthy volunteers with no special singing experience. We found right hemispheric volume increases in professional singers in ventral primary somatosensory cortex (larynx S1) and adjacent rostral supramarginal gyrus (BA40), as well as in secondary somatosensory (S2) and primary auditory cortices (A1). Moreover, we found that earlier commencement with vocal training correlated with increased gray-matter volume in S1. However, in contrast to studies with instrumental musicians, this correlation only emerged in singers who began their formal training after the age of 14years, when speech motor development has reached its first plateau. Structural data thus confirm and extend previous functional reports suggesting a pivotal role of somatosensation in vocal motor control with increased experience in singing. Results furthermore indicate a sensitive period for developing additional vocal skills after speech motor coordination has matured. PMID:27034024

  10. Differences in brain structure in patients with distinct sites of chronic pain A voxel-based morphometric analysis

    Institute of Scientific and Technical Information of China (English)

    Cuiping Mao; Longxiao Wei; Qiuli Zhang; Xia Liao; Xiaoli Yang; Ming Zhang

    2013-01-01

    A reduction in gray matter volume is common in patients with chronic back pain, and different types of pain are associated with gray matter abnormalities in distinct brain regions. To examine ences in brain morphology in patients with low back pain or neck and upper back pain, we gated changes in gray matter volume in chronic back pain patients having different sites of pain using voxel-based morphometry. A reduction in cortical gray matter volume was found primarily in the left postcentral gyrus and in the left precuneus and bilateral cuneal cortex of patients with low back pain. In these patients, there was an increase in subcortical gray matter volume in the bilateral putamen and accumbens, right pal idum, right caudate nucleus, and left amygdala. In upper back pain patients, reduced cortical gray matter volume was found in the left precentral and left tral cortices. Our findings suggest that regional gray matter volume abnormalities in low back pain patients are more extensive than in upper back pain patients. Subcortical gray matter volume in-creases are found only in patients with low back pain.

  11. Voxel-based analysis of grey matter magnetization transfer ratio maps in early relapsing remitting multiple sclerosis.

    Science.gov (United States)

    Audoin, B; Davies, G; Rashid, W; Fisniku, L; Thompson, A J; Miller, D H

    2007-05-01

    Previous studies using magnetization transfer ratio (MTR) histogram analysis have demonstrated the existence of global grey matter (GM) abnormalities in patients with early relapsing-remitting multiple sclerosis (RRMS). However, MTR histogram analysis does not provide any information on the localization of the morphological changes within the GM. The aim of this study was to investigate the localization of GM injury in early RRMS, performing voxel-based analysis of GM MTR maps. Statistical mapping analysis of GM MTR maps was performed in a group of 38 patients with early RRMS and 45 healthy controls. Between-group comparisons (P<0.05, corrected for multiple comparisons) demonstrated significant GM MTR decrease in patients located in the bilateral lenticular nuclei, the bilateral insula, the left posterior cingulate cortex, and the right orbitofrontal cortex. To limit the potential confounding effect of regional GM atrophy, the percentages of GM were assessed in the regions showing significant MTR decrease, and no GM atrophy was evidenced in these regions. This study demonstrates that several GM regions are commonly affected in patients with early RRMS. Predominant involvement of these structures may be partly related to their vulnerability to anterograde or retrograde degeneration from transected axons in the white matter and/or to the predominant localization of GM demyelinating lesions in such regions. PMID:17463071

  12. Voxel-based analyses of gray/white matter volume and diffusion tensor data in major depression. Presidential award proceedings

    International Nuclear Information System (INIS)

    Previous neuroimaging studies have revealed that frontolimbic dysfunction may contribute to the pathophysiology of major depressive disorder. We used voxel-based analysis to simultaneously elucidate regional changes in gray/white matter volume, mean diffusivity (MD), and fractional anisotropy (FA) in the central nervous system of patients with unipolar major depression. We studied 21 right-handed patients and 42 age- and gender-matched right-handed normal subjects without central nervous system disorders. All image processing and statistical analyses were performed using SPM5 software. Local areas showing significant gray matter volume reduction in depressive patients compared with normal controls were observed in the right parahippocampal gyrus, hippocampus, bilateral middle frontal gyri, bilateral anterior cingulate cortices, left parietal and occipital lobes, and right superior temporal gyrus. Local areas showing increased mean diffusivity in depressive patients were observed in the bilateral parahippocampal gyri, hippocampus, pons, cerebellum, left frontal and temporal lobes, and right frontal lobe. There was no significant difference between the 2 groups for fractional anisotropy and white matter volume in the entire brain. Although there was no local area in which FA and MD were significantly correlated with disease severity, FA tended to correlate negatively with depression days (total accumulated days in depressive state) in the right anterior cingulate and the left frontal white matter (FDR-corrected P=0.055 for both areas). These results suggest that the frontolimbic neural circuit may play an important role in the neuropathology of patients with major depression. (author)

  13. Brain involvement in patients with inflammatory bowel disease: a voxel-based morphometry and diffusion tensor imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Zikou, Anastasia K.; Astrakas, Loukas G.; Tzarouchi, Loukia C.; Argyropoulou, Maria I. [University of Ioannina, Department of Radiology, Medical School, Ioannina (Greece); Kosmidou, Maria; Tsianos, Epameinondas [University of Ioannina, 1st Department of Internal Medicine (Hepato-Gastroenterology Unit), Medical School, Ioannina (Greece)

    2014-10-15

    To investigate structural brain changes in inflammatory bowel disease (IBD). Brain magnetic resonance imaging (MRI) was performed on 18 IBD patients (aged 45.16 ± 14.71 years) and 20 aged-matched control subjects. The imaging protocol consisted of a sagittal-FLAIR, a T1-weighted high-resolution three-dimensional spoiled gradient-echo sequence, and a multisession spin-echo echo-planar diffusion-weighted sequence. Differences between patients and controls in brain volume and diffusion indices were evaluated using the voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) methods, respectively. The presence of white-matter hyperintensities (WMHIs) was evaluated on FLAIR images. VBM revealed decreased grey matter (GM) volume in patients in the fusiform and the inferior temporal gyrus bilaterally, the right precentral gyrus, the right supplementary motor area, the right middle frontal gyrus and the left superior parietal gyrus (p < 0.05). TBSS showed decreased axial diffusivity (AD) in the right corticospinal tract and the right superior longitudinal fasciculus in patients compared with controls. A larger number of WMHIs was observed in patients (p < 0.05). Patients with IBD show an increase in WMHIs and GM atrophy, probably related to cerebral vasculitis and ischaemia. Decreased AD in major white matter tracts could be a secondary phenomenon, representing Wallerian degeneration. (orig.)

  14. Restraint of appetite and reduced regional brain volumes in anorexia nervosa: a voxel-based morphometric study

    Directory of Open Access Journals (Sweden)

    Brooks Samantha J

    2011-11-01

    Full Text Available Abstract Background Previous Magnetic Resonance Imaging (MRI studies of people with anorexia nervosa (AN have shown differences in brain structure. This study aimed to provide preliminary extensions of this data by examining how different levels of appetitive restraint impact on brain volume. Methods Voxel based morphometry (VBM, corrected for total intracranial volume, age, BMI, years of education in 14 women with AN (8 RAN and 6 BPAN and 21 women (HC was performed. Correlations between brain volume and dietary restraint were done using Statistical Package for the Social Sciences (SPSS. Results Increased right dorsolateral prefrontal cortex (DLPFC and reduced right anterior insular cortex, bilateral parahippocampal gyrus, left fusiform gyrus, left cerebellum and right posterior cingulate volumes in AN compared to HC. RAN compared to BPAN had reduced left orbitofrontal cortex, right anterior insular cortex, bilateral parahippocampal gyrus and left cerebellum. Age negatively correlated with right DLPFC volume in HC but not in AN; dietary restraint and BMI predicted 57% of variance in right DLPFC volume in AN. Conclusions In AN, brain volume differences were found in appetitive, somatosensory and top-down control brain regions. Differences in regional GMV may be linked to levels of appetitive restraint, but whether they are state or trait is unclear. Nevertheless, these discrete brain volume differences provide candidate brain regions for further structural and functional study in people with eating disorders.

  15. Development of an MRI rating scale for multiple brain regions: comparison with volumetrics and with voxel-based morphometry

    International Nuclear Information System (INIS)

    We aimed to devise a rating method for key frontal and temporal brain regions validated against quantitative volumetric methods and applicable to a range of dementia syndromes. Four standardised coronal MR images from 36 subjects encompassing controls and cases with Alzheimer's disease (AD) and frontotemporal dementia (FTD) were used. After initial pilot studies, 15 regions produced good intra- and inter-rater reliability. We then validated the ratings against manual volumetry and voxel-based morphometry (VBM) and compared ratings across the subject groups. Validation against both manual volumetry (for both frontal and temporal lobes), and against whole brain VBM, showed good correlation with visual ratings for the majority of the brain regions. Comparison of rating scores across disease groups showed involvement of the anterior fusiform gyrus, anterior hippocampus and temporal pole in semantic dementia, while anterior cingulate and orbitofrontal regions were involved in behavioural variant FTD. This simple visual rating can be used as an alternative to highly technical methods of quantification, and may be superior when dealing with single cases or small groups. (orig.)

  16. Relating inter-individual differences in verbal creative thinking to cerebral structures: an optimal voxel-based morphometry study.

    Directory of Open Access Journals (Sweden)

    Feifei Zhu

    Full Text Available Creativity can be defined the capacity of an individual to produce something original and useful. An important measurable component of creativity is divergent thinking. Despite existing studies on creativity-related cerebral structural basis, no study has used a large sample to investigate the relationship between individual verbal creativity and regional gray matter volumes (GMVs and white matter volumes (WMVs. In the present work, optimal voxel-based morphometry (VBM was employed to identify the structure that correlates verbal creativity (measured by the verbal form of Torrance Tests of Creative Thinking across the brain in young healthy subjects. Verbal creativity was found to be significantly positively correlated with regional GMV in the left inferior frontal gyrus (IFG, which is believed to be responsible for language production and comprehension, new semantic representation, and memory retrieval, and in the right IFG, which may involve inhibitory control and attention switching. A relationship between verbal creativity and regional WMV in the left and right IFG was also observed. Overall, a highly verbal creative individual with superior verbal skills may demonstrate a greater computational efficiency in the brain areas involved in high-level cognitive processes including language production, semantic representation and cognitive control.

  17. Surface errors without semantic impairment in acquired dyslexia: a voxel-based lesion-symptom mapping study.

    Science.gov (United States)

    Binder, Jeffrey R; Pillay, Sara B; Humphries, Colin J; Gross, William L; Graves, William W; Book, Diane S

    2016-05-01

    Patients with surface dyslexia have disproportionate difficulty pronouncing irregularly spelled words (e.g. pint), suggesting impaired use of lexical-semantic information to mediate phonological retrieval. Patients with this deficit also make characteristic 'regularization' errors, in which an irregularly spelled word is mispronounced by incorrect application of regular spelling-sound correspondences (e.g. reading plaid as 'played'), indicating over-reliance on sublexical grapheme-phoneme correspondences. We examined the neuroanatomical correlates of this specific error type in 45 patients with left hemisphere chronic stroke. Voxel-based lesion-symptom mapping showed a strong positive relationship between the rate of regularization errors and damage to the posterior half of the left middle temporal gyrus. Semantic deficits on tests of single-word comprehension were generally mild, and these deficits were not correlated with the rate of regularization errors. Furthermore, the deep occipital-temporal white matter locus associated with these mild semantic deficits was distinct from the lesion site associated with regularization errors. Thus, in contrast to patients with surface dyslexia and semantic impairment from anterior temporal lobe degeneration, surface errors in our patients were not related to a semantic deficit. We propose that these patients have an inability to link intact semantic representations with phonological representations. The data provide novel evidence for a post-semantic mechanism mediating the production of surface errors, and suggest that the posterior middle temporal gyrus may compute an intermediate representation linking semantics with phonology. PMID:26966139

  18. A Voxel-Based Morphometry Study of the Brain of University Students Majoring in Music and Nonmusic Disciplines

    Directory of Open Access Journals (Sweden)

    Kanako Sato

    2015-01-01

    Full Text Available The brain changes flexibly due to various experiences during the developmental stages of life. Previous voxel-based morphometry (VBM studies have shown volumetric differences between musicians and nonmusicians in several brain regions including the superior temporal gyrus, sensorimotor areas, and superior parietal cortex. However, the reported brain regions depend on the study and are not necessarily consistent. By VBM, we investigated the effect of musical training on the brain structure by comparing university students majoring in music with those majoring in nonmusic disciplines. All participants were right-handed healthy Japanese females. We divided the nonmusic students into two groups and therefore examined three groups: music expert (ME, music hobby (MH, and nonmusic (NM group. VBM showed that the ME group had the largest gray matter volumes in the right inferior frontal gyrus (IFG; BA 44, left middle occipital gyrus (BA 18, and bilateral lingual gyrus. These differences are considered to be caused by neuroplasticity during long and continuous musical training periods because the MH group showed intermediate volumes in these regions.

  19. A Voxel-Based Morphometry Study of the Brain of University Students Majoring in Music and Nonmusic Disciplines.

    Science.gov (United States)

    Sato, Kanako; Kirino, Eiji; Tanaka, Shoji

    2015-01-01

    The brain changes flexibly due to various experiences during the developmental stages of life. Previous voxel-based morphometry (VBM) studies have shown volumetric differences between musicians and nonmusicians in several brain regions including the superior temporal gyrus, sensorimotor areas, and superior parietal cortex. However, the reported brain regions depend on the study and are not necessarily consistent. By VBM, we investigated the effect of musical training on the brain structure by comparing university students majoring in music with those majoring in nonmusic disciplines. All participants were right-handed healthy Japanese females. We divided the nonmusic students into two groups and therefore examined three groups: music expert (ME), music hobby (MH), and nonmusic (NM) group. VBM showed that the ME group had the largest gray matter volumes in the right inferior frontal gyrus (IFG; BA 44), left middle occipital gyrus (BA 18), and bilateral lingual gyrus. These differences are considered to be caused by neuroplasticity during long and continuous musical training periods because the MH group showed intermediate volumes in these regions. PMID:26494943

  20. Relationship between personality and gray matter volume in healthy young adults: a voxel-based morphometric study.

    Directory of Open Access Journals (Sweden)

    Fengmei Lu

    Full Text Available This study aims to investigate the neurostructural foundations of the human personality in young adults. High-resolution structural T1-weighted MR images of 71 healthy young individuals were processed using voxel-based morphometric (VBM approach. Multiple regression analyses were performed to identify the associations between personality traits and gray matter volume (GMV. The Eysenck Personality Questionnaire-Revised, Short Scale for Chinese was chosen to assess the personality traits. This scale includes four dimensions, namely, extraversion, neuroticism, psychoticism, and lie. Particularly, we studied on two dimensions (extraversion and neuroticism of Eysenck's personality. Our results showed that extraversion was negatively correlated with GMV of the bilateral amygdala, the bilateral parahippocampal gyrus, the right middle temporal gyrus, and the left superior frontal gyrus, all of which are involved in emotional and social cognitive processes. These results might suggest an association between extraversion and affective processing. In addition, a positive correlation was detected between neuroticism and GMV of the right cerebellum, a key brain region for negative affect coordination. Meanwhile, a negative association was revealed between GMV of the left superior frontal gyrus and neuroticism. These results may prove that neuroticism is related to several brain regions involved in regulating negative emotions. Based on those findings, we concluded that brain regions involved in social cognition and affective process accounted for modulation and shaping of personality traits among young individuals. Results of this study may serve as a basis for elucidating the anatomical factors of personality.

  1. Investigation of the alteration of gray matter volume in children with mental retardation with the optimal voxel-based morphometry

    International Nuclear Information System (INIS)

    Objective: To detect brain structural difference between children with unexplained mental retardation and children with typically normal development. Methods: The high-resolution magnetic MR imaging were obtained from 21 children with unexplained mental retardation and 30 age-matched control children without intellectual disabilities. Voxel-based morphometry analysis with an optimization of spatial segmentation and normalization procedures were applied to compare differences of gray matter volume between the two groups. The total and regional gray matter volume were compared between the two groups with independent t test. Meanwhile, correlation was conducted to analyze the relationship between the total gray matter volume and intelligence quotient (IQ) with partial correlation test. Results: The total gray matter volume was significantly increased in the mental retardation children (1.012±0.079) × 106 mm3] in relative to the controls [(0.956±0.059)×106 mm3, t=-2.80, P0.05). Conclusions: VBM would detect the gray matter abnormalities that were not founded in routine MR scanning. The increase of gray matter volume in the frontal-thalamus network might indicate the delayed maturation of the brain development. This might be one of the causations of' mental retardation in children. (authors)

  2. Brain involvement in patients with inflammatory bowel disease: a voxel-based morphometry and diffusion tensor imaging study

    International Nuclear Information System (INIS)

    To investigate structural brain changes in inflammatory bowel disease (IBD). Brain magnetic resonance imaging (MRI) was performed on 18 IBD patients (aged 45.16 ± 14.71 years) and 20 aged-matched control subjects. The imaging protocol consisted of a sagittal-FLAIR, a T1-weighted high-resolution three-dimensional spoiled gradient-echo sequence, and a multisession spin-echo echo-planar diffusion-weighted sequence. Differences between patients and controls in brain volume and diffusion indices were evaluated using the voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) methods, respectively. The presence of white-matter hyperintensities (WMHIs) was evaluated on FLAIR images. VBM revealed decreased grey matter (GM) volume in patients in the fusiform and the inferior temporal gyrus bilaterally, the right precentral gyrus, the right supplementary motor area, the right middle frontal gyrus and the left superior parietal gyrus (p < 0.05). TBSS showed decreased axial diffusivity (AD) in the right corticospinal tract and the right superior longitudinal fasciculus in patients compared with controls. A larger number of WMHIs was observed in patients (p < 0.05). Patients with IBD show an increase in WMHIs and GM atrophy, probably related to cerebral vasculitis and ischaemia. Decreased AD in major white matter tracts could be a secondary phenomenon, representing Wallerian degeneration. (orig.)

  3. An optimized voxel-based morphometry study in the evaluation of brain structural abnormalities in anisometropic amblyopia patients

    International Nuclear Information System (INIS)

    Objective: To investigate possible neural mechanism of anisometropic amblyopia by analysing the whole brain volume changes both in grey matter and white matter using optimized voxel-based morphometry (VBM). Methods: Twelve anisometropic amblyopia patients and 12 age,gender and handedness matched healthy volunteers underwent 3-dimensional (3D) fast spoiled gradient echo (FSPGR) sequence scanning on 1.5 Tesla MR system. Raw data was processed and analyzed using statistical parametric mapping (SPM) 5. Results: Compared to healthy controls,the grey matter exhibiting significantly decreased volume in patients included right cuneus, bilateral occipital gyrus, right middle frontal gyrus, left middle temporal gyrus, right superior temporal gyrus, right precuneus,and middle part of right cingulate gyrus (clusters > 10). The grey matter showing increased volume in patients included right cerebellum,right parahippocampal gyrus, left precentral gyrus,and left superior frontal gyrus (clusters > 10). The white matter volume in bilateral optic radiation and internal capsule, especially right optic radiation, decreased significantly in patient group (clusters > 10 ). No white matter showed significantly increased volume in patient group. Conclusion: VBM can be used to investigate the changes of grey matter volume and white matter volume in the whole brain of anisometropic amblyopia children, it provides a method to illustrate the presumed neuro-mechanism from a morphologic point of view. (authors)

  4. Cerebral gray matter volume variation in female-to-male transsexuals: a voxel-based morphometric study.

    Science.gov (United States)

    Kim, Tae-Hoon; Kim, Seok-Kwun; Jeong, Gwang-Woo

    2015-12-16

    Several studies seem to support the hypothesis that brain anatomy is associated with transsexualism. However, these studies were still limited because few neuroanatomical findings have been obtained from female-to-male (FtM) transsexuals. This study compared the cerebral regional volumes of gray matter (GM) between FtM transsexuals and female controls using a voxel-based morphometry. Twelve FtM transsexuals who had undergone sex-reassignment surgery and 15 female controls participated in this study. Both groups were age matched and right-handed, with no history of neurological illness. Fifteen female controls were recruited to determine whether GM volumes in FtM transsexuals more closely resembled individuals who shared their biological sex. MRI data were processed using SPM 8 with the diffeomorphic anatomical registration through exponentiated Lie algebra (DARTEL). FtM transsexuals showed significantly larger volumes of the thalamus, hypothalamus, midbrain, gyrus rectus, head of caudate nucleus, precentral gyrus, and subcallosal area compared with the female controls. However, the female controls showed a significantly larger volume in the superior temporal gyrus including Heschl's gyrus and Rolandic operculum. These findings confirm that the volume difference in brain substructures in FtM transsexuals is likely to be associated with transsexualism and that transsexualism is probably associated with distinct cerebral structures, determining gender identity. PMID:26559725

  5. Effect of visual experience on structural organization of the human brain: A voxel based morphometric study using DARTEL

    International Nuclear Information System (INIS)

    Objective: To investigate structural reorganization in the brain with differential visual experience using Voxel-Based Morphometry with Diffeomorphic Anatomic Registration Through Exponentiated Lie algebra algorithm (DARTEL) approach. Materials and methods: High resolution structural MR images were taken in fifteen normal sighted healthy controls, thirteen totally blind subjects and six partial blind subjects. The analysis was carried out using SPM8 software on MATLAB 7.6.0 platform. Results: VBM study revealed gray matter volume atrophy in the cerebellum and left inferior parietal cortex in total blind subjects and in left inferior parietal cortex, right caudate nucleus, and left primary visual cortex in partial blind subjects as compared to controls. White matter volume loss was found in calcarine gyrus in total blind subjects and Thlamus-somatosensory region in partially blind subjects as compared to controls. Besides, an increase in Gray Matter volume was also found in left middle occipital and middle frontal gyrus and right entorhinal cortex, and an increase in White Matter volume was found in superior frontal gyrus, left middle temporal gyrus and right Heschl's gyrus in totally blind subjects as compared to controls. Comparison between total and partial blind subjects revealed a greater Gray Matter volume in left cerebellum of partial blinds and left Brodmann area 18 of total blind subjects. Conclusion: Results suggest that, loss of vision at an early age can induce significant structural reorganization on account of the loss of visual input. These plastic changes are different in early onset of total blindness as compared to partial blindness

  6. Simplifying triangulations

    OpenAIRE

    Bell, Mark C.

    2016-01-01

    We give a new algorithm to simplify a given triangulation with respect to a given curve. The simplification uses flips together with powers of Dehn twists in order to complete in polynomial time in the bit-size of the curve.

  7. Simplified Monitoring System

    CERN Document Server

    Jelinskas, Adomas

    2013-01-01

    This project can be considered as a model for a simplified grid monitoring. In particular, I was creating a specific monitoring instance, which can be easily set up on a machine and, depending on an input information, automatically start monitoring services using Nagios software application. I had to automate the set up process and configuration of the monitoring system in order for the user to use it easily. I developed a script which automatically sets up the monitoring system, configures it and starts monitoring. I put the script, files and instructions in the repository 'https://git.cern.ch/web/?p=cosmic.git;a=summary' under the sub-directory called SNCG.

  8. Simplifying Blepharoplasty.

    Science.gov (United States)

    Zoumalan, Christopher I; Roostaeian, Jason

    2016-01-01

    Blepharoplasty remains one of the most common aesthetic procedures performed today. Its popularity stems partly from the ability to consistently make significant improvements in facial aesthetics with a relatively short operation that carries an acceptable risk profile. In this article, the authors attempt to simplify the approach to both upper and lower lid blepharoplasty and provide an algorithm based on the individual findings for any given patient. The recent trend with both upper and lower lid blepharoplasty has been toward greater volume preservation and at times volume augmentation. A simplified approach to upper lid blepharoplasty focuses on removal of excess skin and judicious removal of periorbital fat. Avoidance of a hollow upper sulcus has been emphasized and the addition of volume with either fat grafting or fillers can be considered. Lower lid blepharoplasty can use a transcutaneous or a transconjunctival approach to address herniated fat pads while blending the lid-cheek junction through release of the orbitomalar ligament and volume augmentation with fat (by repositioning and/or grafting) or injectable fillers. Complications with upper lid blepharoplasty are typically minimal, particularly with conservative skin removal and volume preservation techniques. Lower lid blepharoplasty, conversely, can lead to more serious complications, including lid malposition, and therefore should be approached with great caution. Nevertheless, through an algorithmic approach that meets the needs of each individual patient, the approach to blepharoplasty may be simplified with consistent and predictable results. PMID:26710052

  9. Effect of visual experience on structural organization of the human brain: A voxel based morphometric study using DARTEL

    Energy Technology Data Exchange (ETDEWEB)

    Modi, Shilpi, E-mail: modi_shilpi@yahoo.co.in [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi (India); Bhattacharya, Manisha, E-mail: manishab10@gmail.com [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi (India); Singh, Namita, E-mail: namita23m@gmail.com [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi (India); Tripathi, Rajendra Prasad, E-mail: director@inmas.drdo.in [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi (India); Khushu, Subash, E-mail: skhushu@yahoo.com [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi (India)

    2012-10-15

    Objective: To investigate structural reorganization in the brain with differential visual experience using Voxel-Based Morphometry with Diffeomorphic Anatomic Registration Through Exponentiated Lie algebra algorithm (DARTEL) approach. Materials and methods: High resolution structural MR images were taken in fifteen normal sighted healthy controls, thirteen totally blind subjects and six partial blind subjects. The analysis was carried out using SPM8 software on MATLAB 7.6.0 platform. Results: VBM study revealed gray matter volume atrophy in the cerebellum and left inferior parietal cortex in total blind subjects and in left inferior parietal cortex, right caudate nucleus, and left primary visual cortex in partial blind subjects as compared to controls. White matter volume loss was found in calcarine gyrus in total blind subjects and Thlamus-somatosensory region in partially blind subjects as compared to controls. Besides, an increase in Gray Matter volume was also found in left middle occipital and middle frontal gyrus and right entorhinal cortex, and an increase in White Matter volume was found in superior frontal gyrus, left middle temporal gyrus and right Heschl's gyrus in totally blind subjects as compared to controls. Comparison between total and partial blind subjects revealed a greater Gray Matter volume in left cerebellum of partial blinds and left Brodmann area 18 of total blind subjects. Conclusion: Results suggest that, loss of vision at an early age can induce significant structural reorganization on account of the loss of visual input. These plastic changes are different in early onset of total blindness as compared to partial blindness.

  10. Detection of changes in cerebrospinal fluid space in idiopathic normal pressure hydrocephalus using voxel-based morphometry

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Fumio; Asada, Takashi [University of Tsukuba, Clinical Neuroscience, Medical Sciences for Control of Pathological Process, Graduate School of Comprehensive Human Sciences, Tsukuba-shi, Ibaraki-ken (Japan); Sasaki, Makoto; Kudo, Kohsuke [Iwate Medical University, Advanced Medical Research Center, Morioka (Japan); Takahashi, Satoshi; Narumi, Shinsuke; Terayama, Yasuo [Iwate Medical University, Department of Neurology, Morioka (Japan); Matsuda, Hiroshi [Saitama Medical University International Medical Center, Department of Nuclear Medicine, Saitama (Japan)

    2010-05-15

    We attempted to detect alterations in the cerebrospinal fluid (CSF) space in patients with idiopathic normal pressure hydrocephalus (iNPH) using voxel-based morphometry (VBM). We obtained sagittal volume images of the entire head by three-dimensional T1-weighted magnetic resonance imaging and compared the regional distribution of CSF in 12 patients with iNPH, 14 patients with Alzheimer's disease (AD), and 17 healthy individuals using VBM with automatically extracted CSF objects. VBM demonstrated significant widening at the lateral ventricles and Sylvian fissures and narrowing of the CSF space at the high convexity/midline areas in iNPH patients, compared to the AD patients and healthy controls (p<0.05, after correction with a false-discovery rate). In addition, the ratio of the CSF volume in the lateral ventricle/Sylvian fissure area to that in the high convexity/midline area in iNPH patients (3.9{+-}1.2) was remarkably greater than that in AD patients (1.2{+-}0.3) and controls (0.9{+-}0.3; one-way ANOVA, p <0.001; post hoc Tukey's test, p < 0.001); we could discriminate iNPH patients from those in the other two groups without any overlap, when using a cutoff level of 1.9. VBM using CSF objects can be used to delineate the characteristic alteration of the CSF space in iNPH patients, which has been evaluated by visual interpretation. (orig.)

  11. Comparison of grey matter atrophy between patients with neuromyelitis optica and multiple sclerosis: A voxel-based morphometry study

    International Nuclear Information System (INIS)

    Purpose: Previous studies have established regional grey matter (GM) loss in multiple sclerosis (MS). However, whether there is any regional GM atrophy in neuromyelitis optica (NMO) and the difference between NMO and MS is unclear. The present study addresses this issue by voxel-based morphometry (VBM). Methods: Conventional magnetic resonance imaging (MRI) and T1-weighted three-dimensional MRI were obtained from 26 NMO patients, 26 relapsing–remitting MS (RRMS) patients, and 26 normal controls. An analysis of covariance model assessed with cluster size inference was used to compare GM volume among three groups. The correlations of GM volume changes with disease duration, expanded disability status scale (EDSS) and brain T2 lesion volume (LV) were analyzed. Results: GM atrophy was found in NMO patients in several regions of frontal, temporal, parietal lobes and insula (uncorrected, p < 0.001). While extensive GM atrophy was found in RRMS patients, including most cortical regions and the deep grey matter (corrected for multiple comparisons, p < 0.01). Compared with NMO, those with RRMS had significant GM loss in bilateral thalami, caudate, left parahippocampal gyrus, right hippocampus and insula (corrected, p < 0.01). In RRMS group, regional GM loss in right caudate and bilateral thalami were strongly correlated with brain T2LV. Conclusions: Our study found the difference of GM atrophy between NMO and RRMS patients mainly in deep grey matter. The correlational results suggested axonal degeneration from lesions on T2WI may be a key pathogenesis of atrophy in deep grey matter in RRMS.

  12. Voxel-based morphometry (VBM) based assessment of gray matter loss in medial temporal lobe epilepsy; comparison with FDG PET

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hye Jin; Lee, Ho Young; Lee, Jae Sung; Kang, Eun Joo; Lee, Sang Gun; Chang, Kee Hyun; Lee, Dong Soo [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    2004-02-01

    The aims of this study were to find brain regions in which gray matter volume was reduced and to show the capability of voxel-based morphometry (VBM) analysis for lateralizing epileptogenic zones in medial temporal lobe epilepsy (mTLE). The findings were compared with fluorodeoxyglucose positron emission tomography (FDG PET). MR T1-weighted images of 12 left mTLE and 11 right mTLE patients were compared with those of 37 normal controls. Images were transformed to standard MNI space and averaged in order to create study-specific brain template. Each image was normalized to this local template and brain tissues were segmented. Modulation VBM analysis was performed in order to observe gray matter volume change. Gray matter was smoothed with a Gaussian kernel. After these preprocessing, statistical analysis was performed using statistical parametric mapping software (SPM99). FDG PET images were compared with those of 22 normal controls using SPM. Gray matter volume was significantly reduced in the left amygdala and hippocampus in left mTLE. In addition, volume of cerebellum, anterior cingulate, and fusiform gyrus in both sides and left insula was reduced. In right mTLE, volume was reduced significantly in right hippocampus. In contrast, FDG uptake was decreased in broad areas of left or right temporal lobes in left TLE and right TLE, respectively. Gray matter loss was found in the ipsilateral hippocampus by modulation VBM analysis in medial temporal lobe epilepsy. This VBM analysis might be useful in lateralizing the epileptogenic zones in medial temporal lobe epilepsy, while SPM analysis of FDG PET disclosed hypometabolic epileptogenic zones.

  13. Voxel-based morphometry (VBM) based assessment of gray matter loss in medial temporal lobe epilepsy; comparison with FDG PET

    International Nuclear Information System (INIS)

    The aims of this study were to find brain regions in which gray matter volume was reduced and to show the capability of voxel-based morphometry (VBM) analysis for lateralizing epileptogenic zones in medial temporal lobe epilepsy (mTLE). The findings were compared with fluorodeoxyglucose positron emission tomography (FDG PET). MR T1-weighted images of 12 left mTLE and 11 right mTLE patients were compared with those of 37 normal controls. Images were transformed to standard MNI space and averaged in order to create study-specific brain template. Each image was normalized to this local template and brain tissues were segmented. Modulation VBM analysis was performed in order to observe gray matter volume change. Gray matter was smoothed with a Gaussian kernel. After these preprocessing, statistical analysis was performed using statistical parametric mapping software (SPM99). FDG PET images were compared with those of 22 normal controls using SPM. Gray matter volume was significantly reduced in the left amygdala and hippocampus in left mTLE. In addition, volume of cerebellum, anterior cingulate, and fusiform gyrus in both sides and left insula was reduced. In right mTLE, volume was reduced significantly in right hippocampus. In contrast, FDG uptake was decreased in broad areas of left or right temporal lobes in left TLE and right TLE, respectively. Gray matter loss was found in the ipsilateral hippocampus by modulation VBM analysis in medial temporal lobe epilepsy. This VBM analysis might be useful in lateralizing the epileptogenic zones in medial temporal lobe epilepsy, while SPM analysis of FDG PET disclosed hypometabolic epileptogenic zones

  14. Larger mid-dorsolateral prefrontal gray matter volume in young binge drinkers revealed by voxel-based morphometry.

    Directory of Open Access Journals (Sweden)

    Sonia Doallo

    Full Text Available Binge drinking or heavy episodic drinking is a high prevalent pattern of alcohol consumption among young people in several countries. Despite increasing evidence that binge drinking is associated with impairments in executive aspects of working memory (i.e. self-ordered working memory, processes known to depend on the mid-dorsolateral prefrontal cortex (Brodmann areas 46 and 9, less is known about the impact of binge drinking on prefrontal gray matter integrity. Here, we investigated the effects of binge drinking on gray matter volume of mid- dorsolateral prefrontal cortex in youths. We used voxel-based morphometry on the structural magnetic resonance images of subjects reporting a persistent (at least three years binge drinking pattern of alcohol use (n = 11; age 22.43 ± 1.03 and control subjects (n = 21; age 22.18 ± 1.08 to measure differences in gray matter volume between both groups. In a region of interest analysis of the mid-dorsolateral prefrontal cortex, after co-varying for age and gender, we observed significantly larger gray matter volume in the left mid-dorsolateral prefrontal cortex (Brodmann areas 46 and 9 in binge drinkers in comparison with control subjects. Furthermore, there was a significant positive correlation between left mid-dorsolateral prefrontal cortex volume and Self-Ordered Pointing Test (SOPT total errors score in binge drinkers. The left mid-dorsolateral prefrontal cortex volume also correlated with the quantity and speed of alcohol intake. These findings indicate that a repeated exposure to alcohol -that does not meet criteria for alcohol dependence- throughout post-adolescent years and young adulthood is linked with structural anomalies in mid-dorsolateral prefrontal regions critically involved in executive aspects of working memory.

  15. Voxel-based registration of simulated and real patient CBCT data for accurate dental implant pose estimation

    Science.gov (United States)

    Moreira, António H. J.; Queirós, Sandro; Morais, Pedro; Rodrigues, Nuno F.; Correia, André Ricardo; Fernandes, Valter; Pinho, A. C. M.; Fonseca, Jaime C.; Vilaça, João. L.

    2015-03-01

    The success of dental implant-supported prosthesis is directly linked to the accuracy obtained during implant's pose estimation (position and orientation). Although traditional impression techniques and recent digital acquisition methods are acceptably accurate, a simultaneously fast, accurate and operator-independent methodology is still lacking. Hereto, an image-based framework is proposed to estimate the patient-specific implant's pose using cone-beam computed tomography (CBCT) and prior knowledge of implanted model. The pose estimation is accomplished in a threestep approach: (1) a region-of-interest is extracted from the CBCT data using 2 operator-defined points at the implant's main axis; (2) a simulated CBCT volume of the known implanted model is generated through Feldkamp-Davis-Kress reconstruction and coarsely aligned to the defined axis; and (3) a voxel-based rigid registration is performed to optimally align both patient and simulated CBCT data, extracting the implant's pose from the optimal transformation. Three experiments were performed to evaluate the framework: (1) an in silico study using 48 implants distributed through 12 tridimensional synthetic mandibular models; (2) an in vitro study using an artificial mandible with 2 dental implants acquired with an i-CAT system; and (3) two clinical case studies. The results shown positional errors of 67+/-34μm and 108μm, and angular misfits of 0.15+/-0.08° and 1.4°, for experiment 1 and 2, respectively. Moreover, in experiment 3, visual assessment of clinical data results shown a coherent alignment of the reference implant. Overall, a novel image-based framework for implants' pose estimation from CBCT data was proposed, showing accurate results in agreement with dental prosthesis modelling requirements.

  16. Voxel-based statistical analysis of cerebral glucose metabolism in patients with permanent vegetative state after acquired brain injury

    Institute of Scientific and Technical Information of China (English)

    Yong Wook Kim; Hyoung Seop Kim; Young-Sil An; Sang Hee Im

    2010-01-01

    Background Permanent vegetative state is defined as the impaired level of consciousness longer than 12 months after traumatic causes and 3 months after non-traumatic causes of brain injury. Although many studies assessed the cerebral metabolism in patients with acute and persistent vegetative state after brain injury, few studies investigated the cerebral metabolism in patients with permanent vegetative state. In this study, we performed the voxel-based analysis of cerebral glucose metabolism and investigated the relationship between regional cerebral glucose metabolism and the severity of impaired consciousness in patients with permanent vegetative state after acquired brain injury.Methods We compared the regional cerebral glucose metabolism as demonstrated by F-18 fluorodeoxyglucose positron emission tomography from 12 patients with permanent vegetative state after acquired brain injury with those from 12 control subjects. Additionally, covariance analysis was performed to identify regions where decreased changes in regional cerebral glucose metabolism significantly correlated with a decrease of level of consciousness measured by JFK-coma recovery scare. Statistical analysis was performed using statistical parametric mapping.Results Compared with controls, patients with permanent vegetative state demonstrated decreased cerebral glucose metabolism in the left precuneus, both posterior cingulate cortices, the left superior parietal lobule (Pcorrected <0.001), and increased cerebral glucose metabolism in the both cerebellum and the right supramarginal cortices (Pcorrected <0.001). In the covariance analysis, a decrease in the level of consciousness was significantly correlated with decreased cerebral glucose metabolism in the both posterior cingulate cortices (Puncorrected <0.005).Conclusion Our findings suggest that the posteromedial parietal cortex, which are part of neural network for consciousness, may be relevant structure for pathophysiological mechanism

  17. Brain atrophy and neuropsychological outcome after treatment of ruptured anterior cerebral artery aneurysms: a voxel-based morphometric study

    Energy Technology Data Exchange (ETDEWEB)

    Bendel, Paula; Koskenkorva, Paeivi; Vanninen, Ritva [Kuopio University Hospital and University of Kuopio, Department of Clinical Radiology, Kuopio (Finland); Koivisto, Timo; Aeikiae, Marja [Kuopio University Hospital and University of Kuopio, Department of Neurosurgery, Kuopio (Finland); Niskanen, Eini [Kuopio University Hospital and University of Kuopio, Department of Neurology, Kuopio (Finland); Kuopio University Hospital and University of Kuopio, Department of Physics, Kuopio (Finland); Koenoenen, Mervi [Kuopio University Hospital and University of Kuopio, Department of Clinical Radiology, Kuopio (Finland); Kuopio University Hospital and University of Kuopio, Department of Clinical Neurophysiology, Kuopio (Finland); Haenninen, Tuomo [Kuopio University Hospital and University of Kuopio, Department of Neurology, Kuopio (Finland)

    2009-11-15

    Cognitive impairment after aneurysmal subarachnoid hemorrhage (aSAH) is frequently detected. Here, we describe the pattern of cerebral (gray matter) atrophy and its clinical relevance after treatment of aSAH caused by a ruptured anterior cerebral artery (ACA) aneurysm. Thirty-seven aSAH patients with ACA aneurysm (17 surgical, 20 endovascular treatment) and a good or moderate clinical outcome (Glasgow Outcome Scale V or IV) and 30 controls underwent brain MRI. Voxel-based morphometric analysis was applied to compare the patients and controls. Patients also underwent a detailed neuropsychological assessment. The comparisons between controls and either all patients (n=37) or the subgroup of surgically treated patients (n=17) revealed bilateral cortical atrophy in the frontal lobes, mainly in the basal areas. The brainstem, bilateral thalamic and hypothalamic areas, and ipsilateral caudate nucleus were also involved. Small areas of atrophy were detected in temporal lobes. The hippocampus and parahippocampal gyrus showed atrophy ipsilateral to the surgical approach. In the subgroup of endovascularly treated patients (n = 15), small areas of atrophy were detected in the bilateral orbitofrontal cortex and in the thalamic region. Twenty patients (54%) showed cognitive deficits in neuropsychological assessment. Group analysis after aSAH and treatment of the ruptured ACA aneurysm revealed gray matter atrophy, principally involving the frontobasal cortical areas and hippocampus ipsilateral to the surgical approach. Areas of reduced gray matter were more pronounced after surgical than endovascular treatment. Together with possible focal cortical infarctions and brain retraction deficits in individual patients, this finding may explain the neuropsychological disturbances commonly detected after treatment of ruptured ACA aneurysms. (orig.)

  18. Brain atrophy and neuropsychological outcome after treatment of ruptured anterior cerebral artery aneurysms: a voxel-based morphometric study

    International Nuclear Information System (INIS)

    Cognitive impairment after aneurysmal subarachnoid hemorrhage (aSAH) is frequently detected. Here, we describe the pattern of cerebral (gray matter) atrophy and its clinical relevance after treatment of aSAH caused by a ruptured anterior cerebral artery (ACA) aneurysm. Thirty-seven aSAH patients with ACA aneurysm (17 surgical, 20 endovascular treatment) and a good or moderate clinical outcome (Glasgow Outcome Scale V or IV) and 30 controls underwent brain MRI. Voxel-based morphometric analysis was applied to compare the patients and controls. Patients also underwent a detailed neuropsychological assessment. The comparisons between controls and either all patients (n=37) or the subgroup of surgically treated patients (n=17) revealed bilateral cortical atrophy in the frontal lobes, mainly in the basal areas. The brainstem, bilateral thalamic and hypothalamic areas, and ipsilateral caudate nucleus were also involved. Small areas of atrophy were detected in temporal lobes. The hippocampus and parahippocampal gyrus showed atrophy ipsilateral to the surgical approach. In the subgroup of endovascularly treated patients (n = 15), small areas of atrophy were detected in the bilateral orbitofrontal cortex and in the thalamic region. Twenty patients (54%) showed cognitive deficits in neuropsychological assessment. Group analysis after aSAH and treatment of the ruptured ACA aneurysm revealed gray matter atrophy, principally involving the frontobasal cortical areas and hippocampus ipsilateral to the surgical approach. Areas of reduced gray matter were more pronounced after surgical than endovascular treatment. Together with possible focal cortical infarctions and brain retraction deficits in individual patients, this finding may explain the neuropsychological disturbances commonly detected after treatment of ruptured ACA aneurysms. (orig.)

  19. Voxel-based morphometry analysis reveals frontal brain differences in participants with ADHD and their unaffected siblings

    Science.gov (United States)

    Bralten, Janita; Greven, Corina U.; Franke, Barbara; Mennes, Maarten; Zwiers, Marcel P.; Rommelse, Nanda N.J.; Hartman, Catharina; van der Meer, Dennis; O’Dwyer, Laurence; Oosterlaan, Jaap; Hoekstra, Pieter J.; Heslenfeld, Dirk; Arias-Vasquez, Alejandro; Buitelaar, Jan K.

    2016-01-01

    Background Data on structural brain alterations in patients with attention-deficit/hyperactivity disorder (ADHD) have been inconsistent. Both ADHD and brain volumes have a strong genetic loading, but whether brain alterations in patients with ADHD are familial has been underexplored. We aimed to detect structural brain alterations in adolescents and young adults with ADHD compared with healthy controls. We examined whether these alterations were also found in their unaffected siblings, using a uniquely large sample. Methods We performed voxel-based morphometry analyses on MRI scans of patients with ADHD, their unaffected siblings and typically developing controls. We identified brain areas that differed between participants with ADHD and controls and investigated whether these areas were different in unaffected siblings. Influences of medication use, age, sex and IQ were considered. Results Our sample included 307 patients with ADHD, 169 unaffected siblings and 196 typically developing controls (mean age 17.2 [range 8–30] yr). Compared with controls, participants with ADHD had significantly smaller grey matter volume in 5 clusters located in the precentral gyrus, medial and orbitofrontal cortex, and (para)cingulate cortices. Unaffected siblings showed intermediate volumes significantly different from controls in 4 of these clusters (all except the precentral gyrus). Medication use, age, sex and IQ did not have an undue influence on the results. Limitations Our sample was heterogeneous, most participants with ADHD were taking medication, and the comparison was cross-sectional. Conclusion Brain areas involved in decision making, motivation, cognitive control and motor functioning were smaller in participants with ADHD than in controls. Investigation of unaffected siblings indicated familiality of 4 of the structural brain differences, supporting their potential in molecular genetic analyses in ADHD research. PMID:26679925

  20. An optimized voxel-based morphometry study of gray matter abnormalities in patients with obsessive-compulsive disorder

    International Nuclear Information System (INIS)

    Objective: To explore changes of gray matter volume in patients with obsessive- compulsive disorder (OCD) in Chinese Han population using optimized voxel-based morphometry (VBM), and investigate its relationship with clinical symptoms. Methods: Twenty patients with OCD and 20 age, sex and handedness matched healthy controls were scanned using 3D-T1 images on a 3.0 T MR system. The high resolution T1WI was preprocessed according to the optimized VBM protocol in Statistical Parametric Mapping (SPM5). Two-sample t test was performed to characterize the differences of the gray matter volume (GMV) between the OCD patients and healthy controls, and the correlations between the GMV and symptom severity and cumulative illness duration were examined using Pearson correlation in SPSS 16.0, respectively. Results: Compared to controls, OCD patients demonstrated increased GMV in left thalamus, right thalamus and left cerebellum after false discovery rate (FDR) correction. No areas of significantly decreased GMV was observed in OCD patients in relative to healthy controls. The mean eigenvalue ranged from 0.5782 to 0.889 representing the left thalamus volume of OCD patients was 0.6813±0.0718, and that ranged from 0.5546 to 0.9062 was 0.6869±0.0808 for right thalamus. The mean eigenvalues were positively correlated in bilateral thalamus (r=0.94, P<0.01). Conclusion: Using optimized VBM, the current research indicates that the pathophysiology of OCD is associated with GMV abnormalities not only in cortico-striato-thalamo-cortical (CSTC) circuit, but also in the cerebellum. (authors)

  1. Numerical Transcoding Proficiency in 10-Year-Old Schoolchildren is Associated with Gray Matter Inter-Individual Differences: A Voxel-Based Morphometry Study

    OpenAIRE

    Lubin, Amélie; Rossi, Sandrine; Simon, Grégory; Lanoë, Céline; Leroux, Gaëlle; Poirel, Nicolas; Pineau, Arlette; Houdé, Olivier

    2013-01-01

    Are individual differences in numerical performance sustained by variations in gray matter volume in schoolchildren? To our knowledge, this challenging question for neuroeducation has not yet been investigated in typical development. We used the Voxel-Based Morphometry method to search for possible structural brain differences between two groups of 10-year-old schoolchildren (N = 22) whose performance differed only in numerical transcoding between analog and symbolic systems. The results indi...

  2. Numerical transcoding proficiency in 10-year-old schoolchildren is associated with grey-matter interindividual differences: A voxel-based morphometry study

    OpenAIRE

    Amélie eLubin; Sandrine eRossi; Gregory eSimon; Céline eLanoë; Gaëlle eLeroux; Nicolas ePoirel; Arlette ePineau; Olivier eHoudé

    2013-01-01

    Are individual differences in numerical performance sustained by variations in grey matter volume in schoolchildren? To our knowledge, this challenging question for neuroeducation has not yet been investigated in typical development. We used the Voxel-Based Morphometry method to search for possible structural brain differences between two groups of 10-year-old schoolchildren (N=22) whose performance differed only in numerical transcoding between analog and symbolic systems. The results indica...

  3. Advances of voxel-based morphometry analysis algorithm%基于像素的形态学分析算法的研究进展

    Institute of Scientific and Technical Information of China (English)

    程传力; 赵书俊; 聂彬彬; 单保慈

    2011-01-01

    本文主要对基于像素的形态测量学算法(VBM)的发展和改进进行综述,重点讨论近年来发展起来的DARTEL算法.%The development and improvement of voxel-based morphometry (VBM) were reviewed in this paper, especially focused on the DARTEL algorithm which developed rapidly in recent years.

  4. White Matter Atrophy in Patients with Mesial Temporal Lobe Epilepsy: Voxel-Based Morphometry Analysis of T1- and T2-Weighted MR Images

    OpenAIRE

    Barbara Braga; Yasuda, Clarissa L.; Fernando Cendes

    2012-01-01

    Introduction. Mesial temporal lobe epilepsy (MTLE) associated with hippocampal sclerosis is highly refractory to clinical treatment. MRI voxel-based morphometry (VBM) of T1-weighted images has revealed a widespread pattern of gray matter (GM) and white matter (WM) atrophy in MTLE. Few studies have investigated the role of T2-weighted images in revealing WM atrophy using VBM. Objectives. To compare the results of WM atrophy between T1- and T2-weighted images through VBM. Methods. We selected 2...

  5. Brain structural changes and their correlation with vascular disease in type 2 diabetes mellitus patients: a voxel-based morphometric study

    OpenAIRE

    Wang, Chunxia; Fu, Kailiang; Liu, Huaijun; Xing, Fei; Zhang, Songyun

    2014-01-01

    Voxel-based morphometry has been used in the study of alterations in brain structure in type 1 diabetes mellitus patients. These changes are associated with clinical indices. The age at onset, pathogenesis, and treatment of type 1 diabetes mellitus are different from those for type 2 diabetes mellitus. Thus, type 1 and type 2 diabetes mellitus may have different impacts on brain structure. Only a few studies of the alterations in brain structure in type 2 diabetes mellitus patients using voxe...

  6. Immunohistochemical Ki-67/KL1 double stains increase accuracy of Ki-67 indices in breast cancer and simplify automated image analysis

    DEFF Research Database (Denmark)

    Nielsen, Patricia S; Bentzer, Nina K; Jensen, Vibeke;

    2014-01-01

    BACKGROUND: Ki-67 immunohistochemical expression is a prognostic and predictive marker in many breast cancer studies. Instead of the conventional time-consuming score of Ki-67 single stains associated with low reproducibility, Ki-67/KL1 double stains may facilitate fast, repeatable quantification...... different regions: hot spots, global tumor areas, and invasive fronts. MATERIALS AND METHODS: Paraffin-embedded, formalin-fixed tissue from 100 consecutive patients with invasive breast cancer was immunohistochemically stained for Ki-67 and Ki-67/KL1. Ki-67 was manually scored in different regions by 2...... stains, Ki-67 should be quantified on double stains to reach a higher accuracy. Automated indices correlated well with manual estimates and tumor characteristics, and they are thus possibly valuable tools in future exploration of Ki-67 in breast cancer....

  7. Volume changes of whole brain gray matter in pediatric patients with Tourette syndrome: evidence from voxel-based morphometry

    International Nuclear Information System (INIS)

    Objectives: To identify the related abnormalities of gray matter in pediatric patients with Tourette syndrome (TS) by using the optimized voxel-based morphometry (VBM). Methods: Three dimensional T1WI was acquired in 31 TS children (28 boys, 3 girts, mean age 8 years, range 4-15 years) and 50 age- and sex-matched controls on a 1.5 Tesla Philips scanner. Images were pre-processed and analyzed using a version of VBM 2 in SPM 2. The whole brain gray matter volume was compared between the study and control group by using t-test. Multivariate linear regression analysis was used for analyzing the correlation between the change of grey matter volume within each brain region (mm3) and YGTSS score and course of disease of TS patients. Statistical analyses were performed by using SPSS 13.0. Results: Using VBM, significant increases in gray matter volumes in left superior parietal lobule, right cerebellar hemisphere and left parahippocampal gyrus were detected in TS patients, and the volume changes were 4059, 2126 and 84 mm3 (t=3.93, 3.71, 3.58, P<0.05) respectively. Compared to the control group, decreased grey matter volumes were found in medulla and left pons, and the volume changes were 213 and 117 mm3 (t=3.53, 3.48, P<0.05)respectively. Tic severity was not correlated with any volume changes of gray matter in brain (P>0.05, a small volume correction, KE ≥ 10 voxel). Tic course was negatively correlated with the gray matter volume of left parahippocampal gyrus (Beta =-0.391, P=0.039). Conclusions: Using VBM technique, the gray matter abnormalities can be revealed in TS patients without obvious lesions on conventional MR imaging. The increasing volume of temporal and parietal lobes and cerebellar may be an adaptive anatomical change in response to experiential demand. The gray matter volume of the parahippocampal gyrus may be used as one potential objective index for evaluating the prognosis of TS. (authors)

  8. Construction and evaluation of F-18 FDG PET probabilistic MAP for voxel based analysis of the rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Im, K. C.; Kim, J. S.; Na, Y. S.; Moon, D. H.; Ryu, J. S. [Asan Medical Center, Seoul (Korea, Republic of)

    2007-07-01

    The purpose of this study was to develop F-18 FDG PET and MRI template for normal rat brain. Also, feasibility of SPM in detailed regional analysis of molecular changes in the rat brain was explored for F-18 FDG PET imaging of a model of traumatic brain injury (TBI). Ten normal rats were scanned with PET and MRI. The PET images were acquired with 3D mode using microPET focus 120 scanner after injection of 37 MBq F-18 FDG. T2-weighted MR images were acquired using 4.7T MRI system. A MRI-based spatial normalization was used. The PET images were coregistered to T2-weighted MR images. Maximum mutual information (MMI) registrations and affine spatial normalizations were performed using SPM2. The spatial normalization of the MRI to the standard MRI was applied to the integral images. The normalized PET images were averaged voxel wise to create PET template. Eight TBI model rats were subjected to a moderate lateral fluid percussion injury. At 2 days, 1 week, 3 weeks and 5 weeks post FPI, PET images of 8 TBI rats were acquired 4 times. TBI PET images were realigned, spatially normalized to a created PET-template and smoothed (8 mm FWHM). To assess the extent and severity of significant hypo metabolic lesions in TBI compared to normal controls were obtained by a two-sided t-test of SPM (uncorrected p < 0.001, 50 voxels). Visually acceptable PET and MRI templates were created. Registration errors were negligible when MMI procedure was used to register a translated or rotated image volume. Thirty-two PET studies of 8 TBI model subjects were obtained. SPM analysis showed injured distribution of decrease F-18 FDG uptake in TBI rats compared with normal rats. In SPM analysis, the extent and severity of significant hypo metabolic lesions were decreased according to a significant effect of time. At 5 weeks injured animals showed F-18 FDG uptake recovery using SPM analysis. These results indicate that voxel-based method will be useful for future longitudinal studies of rat brain.

  9. Comparison of Alzheimer's disease with vascular dementia and non-dementia using specific voxel-based Z score maps

    International Nuclear Information System (INIS)

    We investigated the ability to discriminate between Alzheimer's disease (AD) and vascular dementia (VaD), and between AD and non-dementia using the program ''easy Z score imaging system'' (eZIS) developed by Matsuda et al., for the diagnosis of very early AD. Of 201 patients, we investigated 12 patients with AD, 10 with VaD, and 9 with non-dementia, who underwent brain perfusion single-photon emission computed tomography by technetium-99m ethyl cysteinate dimer (99mTc-ECD) between February 2005 and September 2006. The sensitivity and specificity of the indicators of specific volume of interest (VOI) analysis, namely, severity, extent, and ratio were evaluated for the distinction of AD from VaD and non-dementia. There was a significant difference in all the criteria for severity, extent, and ratio between AD and non-dementia cases and in the ratio between AD and VaD. Between AD and non-dementia, the sensitivity and specificity of severity were 100% and 45%, respectively, using the cutoff value of 1.19. When using the cutoff value of 14.2 for extent, the sensitivity and specificity were both 100%. Using the cutoff value of 2.22 for ratio, the sensitivity of 42% and specificity of 100% were demonstrated. When comparing AD with VaD, using the cutoff value of 2.22 for ratio, the sensitivity and specificity were 42% and 100%, respectively. Using the cutoff value of 1.5 for ratio, the sensitivity and specificity between AD and VaD were 92% and 80%, respectively, thereby showing the best results. The specific VOI analysis program of AD using specific voxel-based Z score maps is not influenced by interobserver differences among radiologists and is useful to discriminate AD from VaD and non-dementia. However, the setting of the cutoff value at each institution and comparison with original and eZIS images are suggested to distinguish better AD from VaD. (author)

  10. Brain structural changes and their correlation with vascular disease in type 2 diabetes mellitus patients:a voxel-based morphometric study

    Institute of Scientific and Technical Information of China (English)

    Chunxia Wang; Kailiang Fu; Huaijun Liu; Fei Xing; Songyun Zhang

    2014-01-01

    Voxel-based morphometry has been used in the study of alterations in brain structure in type 1 diabetes mellitus patients. These changes are associated with clinical indices. The age at onset, pathogenesis, and treatment of type 1 diabetes mellitus are different from those for type 2 diabetes mellitus. Thus, type 1 and type 2 diabetes mellitus may have different impacts on brain structure. Only a few studies of the alterations in brain structure in type 2 diabetes mellitus patients using voxel-based morphometry have been conducted, with inconsistent results. We detected subtle changes in the brain structure of 23 cases of type 2 diabetes mellitus, and demonstrated that there was no signiifcant difference between the total volume of gray and white matter of the brain of type 2 diabetes mellitus patients and that in controls. Regional atrophy of gray matter mainly occurred in the right temporal and left occipital cortex, while regional atrophy of white matter involved the right temporal lobe and the right cerebellar hemisphere. The ankle-brachial index in patients with type 2 diabetes mellitus strongly correlated with the volume of brain regions in the default mode network. The ankle-brachial index, followed by the level of glycosylated hemoglobin, most strongly correlated with the volume of gray matter in the right temporal lobe. These data suggest that voxel-based morphometry could detect small structural changes in patients with type 2 diabetes mellitus. Early macrovascular atherosclerosis may play a crucial role in subtle brain atro-phy in type 2 diabetes mellitus patients, with chronic hyperglycemia playing a lesser role.

  11. Gray matter atrophy in patients with Parkinson’s disease and those with mild cognitive impairment: a voxel-based morphometry study

    OpenAIRE

    Zhang, Jing; Zhang, Yun-ting; Hu, Wei-dong; Li, Li; Liu, Guang-Yao; Bai, Yu-Ping

    2015-01-01

    Purpose: Mild cognitive impairment is common in Parkinson’s disease, but the underlying pathological mechanism has not been fully understood. To examine the gray matter changes in patients with Parkinson’s disease and those with mild cognitive impairment (MCI) using voxel based Morphometry (VBM). Methods: Magnetic resonance images were obtained from 35 patients with PD and 20 age and sex-matched healthy control subjects. In the PD group, 14 subjects had no MCI and 21 had MCI. MRI 3D structura...

  12. Strategies for improving the Voxel-based statistical analysis for animal PET studies: assessment of cerebral glucose metabolism in cat deafness model

    International Nuclear Information System (INIS)

    In imaging studies of the human brain, voxel-based statistical analysis method was widely used, since these methods were originally developed for the analysis of the human brain data, they are not optimal for the animal brain data. The aim of this study is to optimize the procedures for the 3D voxel-based statistical analysis of cat FDG PET brain images. A microPET Focus 120 scanner was used. Eight cats underwent FDG PET scans twice before and after inducing the deafness. Only the brain and adjacent regions were extracted from each data set by manual masking. Individual PET image at normal and deaf state was realigned to each other to remove the confounding effects by the different spatial normalization parameters on the results of statistical analyses. Distance between the sampling points on the reference image and kernel size of Gaussian filter applied to the images before estimating the realignment parameters were adjusted to 0.5 mm and 2 mm. Both data was then spatial normalized onto study-specific cat brain template. Spatially normalized PET data were smoothed and voxel-based paired t-test was performed. Cerebral glucose metabolism decreased significantly after the loss of hearing capability in parietal lobes, postcentral gyri, STG, MTG, lTG, and IC at both hemisphere and left SC (FDR corrected P < 0.05, k=50). Cerebral glucose metabolism in deaf cats was found to be significantly higher than in controls in the right cingulate (FDR corrected P < 0.05, k=50). The ROI analysis also showed significant reduction of glucose metabolism in the same areas as in the SPM analysis, except for some regions (P < 0.05). Method for the voxel-based analysis of cat brain PET data was optimized for analysis of cat brain PET. This result was also confirmed by ROI analysis. The results obtained demonstrated the high localization accuracy and specificity of the developed method, and were found to be useful for examining cerebral glucose metabolism in a cat cortical deafness model

  13. Strategies for improving the Voxel-based statistical analysis for animal PET studies: assessment of cerebral glucose metabolism in cat deafness model

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Su; Lee, Jae Sung; Park, Min Hyun; Kang, Hye Jin; Im, Ki Chun; Moon, Dae Hyuk; Lim, Sang Moo; Oh, Seung Ha; Lee, Dong Soo [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    In imaging studies of the human brain, voxel-based statistical analysis method was widely used, since these methods were originally developed for the analysis of the human brain data, they are not optimal for the animal brain data. The aim of this study is to optimize the procedures for the 3D voxel-based statistical analysis of cat FDG PET brain images. A microPET Focus 120 scanner was used. Eight cats underwent FDG PET scans twice before and after inducing the deafness. Only the brain and adjacent regions were extracted from each data set by manual masking. Individual PET image at normal and deaf state was realigned to each other to remove the confounding effects by the different spatial normalization parameters on the results of statistical analyses. Distance between the sampling points on the reference image and kernel size of Gaussian filter applied to the images before estimating the realignment parameters were adjusted to 0.5 mm and 2 mm. Both data was then spatial normalized onto study-specific cat brain template. Spatially normalized PET data were smoothed and voxel-based paired t-test was performed. Cerebral glucose metabolism decreased significantly after the loss of hearing capability in parietal lobes, postcentral gyri, STG, MTG, lTG, and IC at both hemisphere and left SC (FDR corrected P < 0.05, k=50). Cerebral glucose metabolism in deaf cats was found to be significantly higher than in controls in the right cingulate (FDR corrected P < 0.05, k=50). The ROI analysis also showed significant reduction of glucose metabolism in the same areas as in the SPM analysis, except for some regions (P < 0.05). Method for the voxel-based analysis of cat brain PET data was optimized for analysis of cat brain PET. This result was also confirmed by ROI analysis. The results obtained demonstrated the high localization accuracy and specificity of the developed method, and were found to be useful for examining cerebral glucose metabolism in a cat cortical deafness model.

  14. Voxel-based analysis of whole-brain effects of age and gender on dopamine transporter SPECT imaging in healthy subjects

    International Nuclear Information System (INIS)

    Several studies have shown age- and gender-related differences in striatal dopamine transporter (DaT) binding. These studies were based on a striatal region on interest approach that may have underestimated these effects and could not evaluate extrastriatal regions. Our aim was to determine the effects at the voxel level of age and gender on whole-brain DaT distribution using [123I]FP-CIT SPECT in healthy subjects. We performed a whole-brain [123I]FP-CIT SPECT voxel-based analysis using SPM8 and a standardized normalization template (p < 0.05, corrected using the false discovery rate method) in 51 healthy subjects aged from 21 to 79 years. We found an age-related DaT binding decrease in the striatum, anterior cingulate/medial frontal cortices and insulo-opercular cortices. Also DaT binding ratios were higher in women than men in the striatum and opercular cortices. This study showed both striatal and extrastriatal age-related and gender-related differences in DaT binding in healthy subjects using a whole-brain voxel-based non-a priori approach. These differences highlight the need for careful age and gender matching in DaT analyses of neuropsychiatric disorders. (orig.)

  15. Global and regional brain volumes normalization in weight-recovered adolescents with anorexia nervosa: preliminary findings of a longitudinal voxel-based morphometry study

    Directory of Open Access Journals (Sweden)

    Bomba M

    2015-03-01

    Full Text Available Monica Bomba,1,* Anna Riva,1,* Sabrina Morzenti,2 Marco Grimaldi,3 Francesca Neri,1 Renata Nacinovich1 1Child and Adolescent Mental Health Department, San Gerardo Hospital, University of Milano-Bicocca, Monza, Italy; 2Medical Physics Department, San Gerardo Hospital, Monza, Italy; 3Department of Radiology, Humanitas Research Hospital, Milan, Italy *These authors contributed equally to this work Abstract: The recent literature on anorexia nervosa (AN suggests that functional and structural abnormalities of cortico-limbic areas might play a role in the evolution of the disease. We explored global and regional brain volumes in a cross-sectional and follow-up study on adolescents affected by AN. Eleven adolescents with AN underwent a voxel-based morphometry study at time of diagnosis and immediately after weight recovery. Data were compared to volumes carried out in eight healthy, age and sex matched controls. Subjects with AN showed increased cerebrospinal fluid volumes and decreased white and gray matter volumes, when compared to controls. Moreover, significant regional gray matter decrease in insular cortex and cerebellum was found at time of diagnosis. No regional white matter decrease was found between samples and controls. Correlations between psychological evaluation and insular volumes were explored. After weight recovery gray matter volumes normalized while reduced global white matter volumes persisted. Keywords: anorexia nervosa, adolescent, gray matter, insula, voxel-based morphometry study

  16. Voxel-based analysis of whole-brain effects of age and gender on dopamine transporter SPECT imaging in healthy subjects

    Energy Technology Data Exchange (ETDEWEB)

    Eusebio, Alexandre; Azulay, Jean-Philippe [APHM, Hopital de la Timone, Service de Neurologie et Pathologie du Mouvement, Marseille (France); CNRS, Aix-Marseille Univ, Institut de Neurosciences de la Timone, Marseille (France); Ceccaldi, Mathieu [APHM, Hopital de la Timone, Service de Neurologie et de Neuropsychologie, Marseille (France); Aix-Marseille Univ, UMR Inserm 1106, Institut de Neurosciences des Systemes, Marseille (France); Girard, Nadine [APHM, Hopital de la Timone, Service de Neuroradiologie diagnostique et interventionnelle, Marseille (France); Mundler, Olivier [APHM, Hopital de la Timone, Service Central de Biophysique et Medecine Nucleaire, Marseille (France); Aix-Marseille Univ, CERIMED, Marseille (France); Guedj, Eric [CNRS, Aix-Marseille Univ, Institut de Neurosciences de la Timone, Marseille (France); APHM, Hopital de la Timone, Service Central de Biophysique et Medecine Nucleaire, Marseille (France); Aix-Marseille Univ, CERIMED, Marseille (France)

    2012-11-15

    Several studies have shown age- and gender-related differences in striatal dopamine transporter (DaT) binding. These studies were based on a striatal region on interest approach that may have underestimated these effects and could not evaluate extrastriatal regions. Our aim was to determine the effects at the voxel level of age and gender on whole-brain DaT distribution using [{sup 123}I]FP-CIT SPECT in healthy subjects. We performed a whole-brain [{sup 123}I]FP-CIT SPECT voxel-based analysis using SPM8 and a standardized normalization template (p < 0.05, corrected using the false discovery rate method) in 51 healthy subjects aged from 21 to 79 years. We found an age-related DaT binding decrease in the striatum, anterior cingulate/medial frontal cortices and insulo-opercular cortices. Also DaT binding ratios were higher in women than men in the striatum and opercular cortices. This study showed both striatal and extrastriatal age-related and gender-related differences in DaT binding in healthy subjects using a whole-brain voxel-based non-a priori approach. These differences highlight the need for careful age and gender matching in DaT analyses of neuropsychiatric disorders. (orig.)

  17. Evaluation of brain perfusion in specific Brodmann areas in Frontotemporal dementia and Alzheimer disease using automated 3-D voxel based analysis

    Science.gov (United States)

    Valotassiou, V.; Papatriantafyllou, J.; Sifakis, N.; Karageorgiou, C.; Tsougos, I.; Tzavara, C.; Zerva, C.; Georgoulias, P.

    2009-05-01

    Introduction. Brain perfusion studies with single-photon emission computed tomography (SPECT) have been applied in demented patients to provide better discrimination between frontotemporal dementia (FTD) and Alzheimer's disease (AD). Aim. To assess the perfusion of specific Brodmann (Br) areas of the brain cortex in FTD and AD patients, using NeuroGam processing program to provide 3D voxel-by-voxel cerebral SPECT analysis. Material and methods. We studied 34 consecutive patients. We used the established criteria for the diagnosis of dementia and the specific established criteria for the diagnosis of FTD and AD. All the patients had a neuropsychological evaluation with a battery of tests including the mini-mental state examination (MMSE).Twenty-six patients (16 males, 10 females, mean age 68.76±6.51 years, education 11.81±4.25 years, MMSE 16.69±9.89) received the diagnosis of FTD and 8 patients (all females, mean age 71.25±10.48 years, education 10±4.6 years, MMSE 12.5±3.89) the diagnosis of AD. All the patients underwent a brain SPECT. We applied the NeuroGam Software for the evaluation of brain perfusion in specific Br areas in the left (L) and right (R) hemispheres. Results. Statistically significant hypoperfusion in FTD compared to AD patients, was found in the following Br areas: 11L (pbrain perfusion SPECT could result in enhanced accuracy for the differential diagnosis between AD and FTD patients.

  18. Evaluation of brain perfusion in specific Brodmann areas in Frontotemporal dementia and Alzheimer disease using automated 3-D voxel based analysis

    International Nuclear Information System (INIS)

    Introduction. Brain perfusion studies with single-photon emission computed tomography (SPECT) have been applied in demented patients to provide better discrimination between frontotemporal dementia (FTD) and Alzheimer's disease (AD). Aim. To assess the perfusion of specific Brodmann (Br) areas of the brain cortex in FTD and AD patients, using NeuroGam processing program to provide 3D voxel-by-voxel cerebral SPECT analysis. Material and methods. We studied 34 consecutive patients. We used the established criteria for the diagnosis of dementia and the specific established criteria for the diagnosis of FTD and AD. All the patients had a neuropsychological evaluation with a battery of tests including the mini-mental state examination (MMSE).Twenty-six patients (16 males, 10 females, mean age 68.76±6.51 years, education 11.81±4.25 years, MMSE 16.69±9.89) received the diagnosis of FTD and 8 patients (all females, mean age 71.25±10.48 years, education 10±4.6 years, MMSE 12.5±3.89) the diagnosis of AD. All the patients underwent a brain SPECT. We applied the NeuroGam Software for the evaluation of brain perfusion in specific Br areas in the left (L) and right (R) hemispheres. Results. Statistically significant hypoperfusion in FTD compared to AD patients, was found in the following Br areas: 11L (p<0.0001), 11R, 20L, 20R, 32L, 38L, 38R, 44L (p<0.001), 32R, 36L, 36R, 45L, 45R, 47R (p<0.01), 9L, 21L, 39R, 44R, 46R, 47L (p<0.05). On the contrary, AD patients presented significant (p<0.05) hypoperfusion in 7R and 39R Br areas. Conclusion. NeuroGam processing program of brain perfusion SPECT could result in enhanced accuracy for the differential diagnosis between AD and FTD patients.

  19. MR diffusion tensor imaging voxel-based analysis of whole brain white matter in patients with amnestic-type mild cognitive impairment and mild Alzheimer disease

    International Nuclear Information System (INIS)

    Objective: To evaluate the microstructural integrity of white matter (WM) in patients with amnestic mild cognitive impairment (aMCI) and mild Alzheimer's disease (AD) using voxel-based analysis (VBA), and investigate the relationship between WM abnormalities and gray matter (GM) atrophy. Methods: Thirty-three cases with aMCI, 32 cases with mild AD and 31 normal aging volunteers as control subjects were scanned on a 3.0 T MR system using diffusion tensor imaging (DTI) and three-dimensional spoiled gradient-recalled (3DSPGR) sequences. Fractional anisotropy (FA) maps and morphological images were preprocessed by SPM5 and voxel-based comparisons between the 2 patient groups and the control group were performed by t test. Results: Relative to the control group, patients with aMCI showed significantly reduced FA value in bilateral frontal, temporal and left occipital WM, left anterior part of cingulum, left inferior parietal lobule, and the WM adjacent to the triangular part of the right lateral ventricle (k ≥ 20 voxels). In mild AD, significantly reduced FA value was found in bilateral hippocampal, inferior parietal lobular, frontal, temporal, and occipital WM, bilateral corpus callosum, anterior part of cingulums, the WM adjacent to the triangular part of the bilateral lateral ventricles, left temporal stem, left thalamus, right precuneus (k ≥ 20 voxels). Significantly reduced GM volume was found in left hippocampus, parahippocampal gyrus, lingual gyrus and superior temporal gyrus, bilateral insulae and middle temporal gyri in aMCI group when compared with control group (k ≥ 50 voxels). In mild AD, significantly reduced GM volume was found in bilateral hippocampi, parahippocampal gyri, amygdalae, thalami, temporal, parietal, frontal, occipital cortex (k ≥ 50 voxels). The pattern of areas with reduced FA differs from that of the GM volumetric reduction. No areas with significantly reduced FA was detected in aMCI compared with mild AD. There was no significant

  20. Density abnormalities in normal-appearing gray matter in the middle-aged brain with white matter hyperintense lesions: a DARTEL-enhanced voxel-based morphometry study

    Directory of Open Access Journals (Sweden)

    Peng Y

    2016-05-01

    Full Text Available Yan Peng,1,* Shenhong Li,2,* Ying Zhuang,3,* Xiaojia Liu,4 Lin Wu,2 Honghan Gong,2 Dewu Liu,1 Fuqing Zhou2 1Burn Center, 2Department of Radiology, The First Affiliated Hospital, Nanchang University, 3Department of Oncology, The Second Hospital of Nanchang, Nanchang, Jiangxi Province, 4Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, People’s Republic of China *These authors contributed equally to this work Background and purpose: Little is known about the structural alterations within gray matter (GM in middle-aged subjects with white matter hyperintense (WMH lesions. Here, we aimed to examine the anatomical changes within the GM and their relationship to WMH lesion loads in middle-aged subjects. Participants and methods: Twenty-three middle-aged subjects with WMH lesions (WMH group and 23 demographically matched healthy control subjects participated in the study. A Diffeomorphic Anatomical Registration Through Exponentiated Liealgebra-enhanced voxel-based morphometry was used to measure the GM density, and the correlations between WMH lesion volume and extracted GM values in abnormal regions were identified by voxel-based morphometry analysis. Results: Compared with the healthy control subjects, the WMH group had a significantly decreased GM density in the left middle frontal gyrus, bilateral anterior cingulate cortex, left and right premotor cortex, and left and right middle cingulate cortex and an increased GM density in the bilateral cerebellum anterior lobe, left middle temporal gyrus, right temporoparietal junction, left and right prefrontal cortex (PFC, and left inferior parietal lobule. A relationship was observed between the normalized WMH lesion volume and the decreased GM density, including the left middle frontal gyrus (ρ=-0.629, P=0.002, bilateral anterior cingulate cortex (ρ=-0.507, P=0.019, right middle cingulate cortex (ρ=-0.484, P=0.026, and

  1. Voxel-based statistical analysis of cerebral glucose metabolism in the rat cortical deafness model by 3D reconstruction of brain from autoradiographic images

    International Nuclear Information System (INIS)

    Animal models of cortical deafness are essential for investigation of the cerebral glucose metabolism in congenital or prelingual deafness. Autoradiographic imaging is mainly used to assess the cerebral glucose metabolism in rodents. In this study, procedures for the 3D voxel-based statistical analysis of autoradiographic data were established to enable investigations of the within-modal and cross-modal plasticity through entire areas of the brain of sensory-deprived animals without lumping together heterogeneous subregions within each brain structure into a large region of interest. Thirteen 2-[1-14C]-deoxy-D-glucose autoradiographic images were acquired from six deaf and seven age-matched normal rats (age 6-10 weeks). The deafness was induced by surgical ablation. For the 3D voxel-based statistical analysis, brain slices were extracted semiautomatically from the autoradiographic images, which contained the coronal sections of the brain, and were stacked into 3D volume data. Using principal axes matching and mutual information maximization algorithms, the adjacent coronal sections were co-registered using a rigid body transformation, and all sections were realigned to the first section. A study-specific template was composed and the realigned images were spatially normalized onto the template. Following count normalization, voxel-wise t tests were performed to reveal the areas with significant differences in cerebral glucose metabolism between the deaf and the control rats. Continuous and clear edges were detected in each image after registration between the coronal sections, and the internal and external landmarks extracted from the spatially normalized images were well matched, demonstrating the reliability of the spatial processing procedures. Voxel-wise t tests showed that the glucose metabolism in the bilateral auditory cortices of the deaf rats was significantly (P<0.001) lower than that in the controls. There was no significantly reduced metabolism in any

  2. Voxel-based statistical analysis of cerebral glucose metabolism in the rat cortical deafness model by 3D reconstruction of brain from autoradiographic images

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Sung; Park, Kwang Suk [Seoul National University College of Medicine, Department of Nuclear Medicine, 28 Yungun-Dong, Chongno-Ku, Seoul (Korea); Seoul National University College of Medicine, Department of Biomedical Engineering, Seoul (Korea); Ahn, Soon-Hyun; Oh, Seung Ha; Kim, Chong Sun; Chung, June-Key; Lee, Myung Chul [Seoul National University College of Medicine, Department of Otolaryngology, Head and Neck Surgery, Seoul (Korea); Lee, Dong Soo; Jeong, Jae Min [Seoul National University College of Medicine, Department of Nuclear Medicine, 28 Yungun-Dong, Chongno-Ku, Seoul (Korea)

    2005-06-01

    Animal models of cortical deafness are essential for investigation of the cerebral glucose metabolism in congenital or prelingual deafness. Autoradiographic imaging is mainly used to assess the cerebral glucose metabolism in rodents. In this study, procedures for the 3D voxel-based statistical analysis of autoradiographic data were established to enable investigations of the within-modal and cross-modal plasticity through entire areas of the brain of sensory-deprived animals without lumping together heterogeneous subregions within each brain structure into a large region of interest. Thirteen 2-[1-{sup 14}C]-deoxy-D-glucose autoradiographic images were acquired from six deaf and seven age-matched normal rats (age 6-10 weeks). The deafness was induced by surgical ablation. For the 3D voxel-based statistical analysis, brain slices were extracted semiautomatically from the autoradiographic images, which contained the coronal sections of the brain, and were stacked into 3D volume data. Using principal axes matching and mutual information maximization algorithms, the adjacent coronal sections were co-registered using a rigid body transformation, and all sections were realigned to the first section. A study-specific template was composed and the realigned images were spatially normalized onto the template. Following count normalization, voxel-wise t tests were performed to reveal the areas with significant differences in cerebral glucose metabolism between the deaf and the control rats. Continuous and clear edges were detected in each image after registration between the coronal sections, and the internal and external landmarks extracted from the spatially normalized images were well matched, demonstrating the reliability of the spatial processing procedures. Voxel-wise t tests showed that the glucose metabolism in the bilateral auditory cortices of the deaf rats was significantly (P<0.001) lower than that in the controls. There was no significantly reduced metabolism in

  3. Cerebral and cerebellar gray matter reduction in first-episode patients with major depressive disorder: A voxel-based morphometry study

    International Nuclear Information System (INIS)

    Purpose: To investigate cerebral and cerebellar gray matter abnormalities in patients with first-episode major depressive disorder (MDD). Materials and methods: We examined the structural difference in regional gray matter density (GMD) between 22 first-episode MDD patients and 30 age-, gender- and education-matched healthy controls by optimized voxel-based morphometry (VBM) based on magnetic resonance imaging. Results: Compared with healthy controls, MDD patients showed decreased GMD in the right medial and left lateral orbitofrontal cortex, right dorsolateral prefrontal cortex (DLPFC), bilateral temporal pole, right superior temporal gyrus, bilateral anterior insular cortex, left parahippocampal gyrus, and left cerebellum. In addition, in MDD patients, there was a negative correlation between GMD values of the right DLPFC and the score of the depression rating scale. Conclusions: Our findings provided additional support for the involvement of limbic-cortical circuits in the pathophysiology of MDD and preliminary evidence that a defect involving the cerebellum may also be implicated.

  4. Numerical transcoding proficiency in 10-year-old schoolchildren is associated with grey-matter interindividual differences: A voxel-based morphometry study

    Directory of Open Access Journals (Sweden)

    Amélie eLubin

    2013-04-01

    Full Text Available Are individual differences in numerical performance sustained by variations in grey matter volume in schoolchildren? To our knowledge, this challenging question for neuroeducation has not yet been investigated in typical development. We used the Voxel-Based Morphometry method to search for possible structural brain differences between two groups of 10-year-old schoolchildren (N=22 whose performance differed only in numerical transcoding between analog and symbolic systems. The results indicated that children with low numerical proficiency have less grey matter volume in the parietal (particularly in the left intraparietal sulcus and the bilateral angular gyri and occipito-temporal areas. All the identified regions have previously been shown to be functionally involved in transcoding between analog and symbolic numerical systems. Our data contribute to a better understanding of the intertwined relationships between mathematics learning and brain structure in healthy schoolchildren.

  5. Numerical Transcoding Proficiency in 10-Year-Old Schoolchildren is Associated with Gray Matter Inter-Individual Differences: A Voxel-Based Morphometry Study.

    Science.gov (United States)

    Lubin, Amélie; Rossi, Sandrine; Simon, Grégory; Lanoë, Céline; Leroux, Gaëlle; Poirel, Nicolas; Pineau, Arlette; Houdé, Olivier

    2013-01-01

    Are individual differences in numerical performance sustained by variations in gray matter volume in schoolchildren? To our knowledge, this challenging question for neuroeducation has not yet been investigated in typical development. We used the Voxel-Based Morphometry method to search for possible structural brain differences between two groups of 10-year-old schoolchildren (N = 22) whose performance differed only in numerical transcoding between analog and symbolic systems. The results indicated that children with low numerical proficiency have less gray matter volume in the parietal (particularly in the left intraparietal sulcus and the bilateral angular gyri) and occipito-temporal areas. All the identified regions have previously been shown to be functionally involved in transcoding between analog and symbolic numerical systems. Our data contribute to a better understanding of the intertwined relationships between mathematics learning and brain structure in healthy schoolchildren. PMID:23630510

  6. White matter abnormalities in young males with antisocial personality disorder Evidence from voxel-based morphometry-diffeomorphic anatomical registration using exponentiated lie algebra analysis

    Institute of Scientific and Technical Information of China (English)

    Daxing Wu; Ying Zhao; Jian Liao; Huifang Yin; Wei Wang

    2011-01-01

    Voxel-based morphometry-diffeomorphic anatomical registration using exponentiated lie algebra analysis was used to investigate the structural characteristics of white matter in young males with antisocial personality disorder (APD) and healthy controls without APD. The results revealed that APD subjects, relative to healthy subjects, exhibited increased white matter volume in the bilateral prefrontal lobe, right insula, precentral gyrus, bilateral superior temporal gyrus, right postcentral gyrus, right inferior parietal lobule, right precuneus, right middle occipital lobe, right parahippocampal gyrus and bilateral cingulate, and decreased volume in the middle temporal cortex and right cerebellum. The white matter volume in the medial frontal gyrus was significantly correlated with antisocial type scores on the Personality Diagnostic Questionnaire in APD subjects. These experimental findings indicate that white matter abnormalities in several brain areas may contribute to antisocial behaviors in APD subjects.

  7. Cerebral and cerebellar gray matter reduction in first-episode patients with major depressive disorder: A voxel-based morphometry study

    Energy Technology Data Exchange (ETDEWEB)

    Peng Jing, E-mail: ppengjjing@sina.com.cn [Department of Radiology, Xuanwu Hospital of Capital Medical University, No. 45, Chang-Chun St, Xuanwu District, Beijing 100053 (China); Liu Jiangtao, E-mail: Liujiangtao813@sina.com [Department of Radiology, Xuanwu Hospital of Capital Medical University, No. 45, Chang-Chun St, Xuanwu District, Beijing 100053 (China); Nie Binbin, E-mail: niebb@ihep.ac.cn [Institute of High Energy Physics, Chinese Academy of Sciences, PO Box 918, Yu-Quan St, Shijingshan District, Beijing 100049 (China); Li Yang, E-mail: Liyang2007428@hotmail.com [Department of Psychiatry, Anding Hospital of Capital Medical University, No. 5, An Kang Hutong, Deshengmen wai, Xicheng District, Beijing 100088 (China); Shan Baoci, E-mail: shanbc@ihep.ac.cn [Institute of High Energy Physics, Chinese Academy of Sciences, PO Box 918, Yu-Quan St, Shijingshan District, Beijing 100049 (China); Wang Gang, E-mail: gangwang@gmail.com [Department of Psychiatry, Anding Hospital of Capital Medical University, No. 5, An Kang Hutong, Deshengmen wai, Xicheng District, Beijing 100088 (China); Li Kuncheng, E-mail: likuncheng1955@yahoo.com.cn [Department of Radiology, Xuanwu Hospital of Capital Medical University, No. 45, Chang-Chun St, Xuanwu District, Beijing 100053 (China)

    2011-11-15

    Purpose: To investigate cerebral and cerebellar gray matter abnormalities in patients with first-episode major depressive disorder (MDD). Materials and methods: We examined the structural difference in regional gray matter density (GMD) between 22 first-episode MDD patients and 30 age-, gender- and education-matched healthy controls by optimized voxel-based morphometry (VBM) based on magnetic resonance imaging. Results: Compared with healthy controls, MDD patients showed decreased GMD in the right medial and left lateral orbitofrontal cortex, right dorsolateral prefrontal cortex (DLPFC), bilateral temporal pole, right superior temporal gyrus, bilateral anterior insular cortex, left parahippocampal gyrus, and left cerebellum. In addition, in MDD patients, there was a negative correlation between GMD values of the right DLPFC and the score of the depression rating scale. Conclusions: Our findings provided additional support for the involvement of limbic-cortical circuits in the pathophysiology of MDD and preliminary evidence that a defect involving the cerebellum may also be implicated.

  8. A comparison of radiation dose measured in CT dosimetry phantoms with calculations using EGS4 and voxel-based computational models

    International Nuclear Information System (INIS)

    CT is a high-dose examination and possibly the dominant contributor to dose from diagnostic radiology. Estimates of organ doses are obtained from Monte Carlo calculations and used to quantify radiation risk. To ensure the validity of using Monte Carlo calculations to estimate actual dose, measurements must be compared with calculations. We have measured doses to CT head and chest dosimetry phantoms and compared them with Monte Carlo (EGS4) calculated doses in voxel-based computational models of the phantoms. The simulation used an x-ray spectrum calculated from the specified values of the scanner's x-ray tube parameters. The scanner's beam-shaping filter was included in the modelling. Measured and calculated doses to both the head and chest phantoms agreed to within 7%. The inclusion of Rayleigh scattering in the calculations has a significant effect if only one slice is scanned but not if multiple slices are scanned. (author)

  9. Voxel based statistical analysis method for microPET studies to assess the cerebral glucose metabolism in cat deafness model: comparison to ROI based method

    International Nuclear Information System (INIS)

    Imaging research on the brain of sensory-deprived cats using small animal PET scanner has gained interest since the abundant information about the sensory system of ths animal is available and close examination of the brain is possible due to larger size of its brain than mouse or rat. In this study, we have established the procedures for 3D voxel-based statistical analysis (SPM) of FDG PET image of cat brain, and confirmed using ROI based-method. FDG PET scans of 4 normal and 4 deaf cats were acquired for 30 minutes using microPET R4 scanner. Only the brain cortices were extracted using a masking and threshold method to facilitate spatial normalization. After spatial normalization and smoothing, 3D voxel-wise and ROI based t-test were performed to identify the regions with significant different FDG uptake between the normal and deaf cats. In ROI analysis, 26 ROIs were drawn on both hemispheres, and regional mean pixel value in each ROI was normalized to the global mean of the brain. Cat brains were spatially normalized well onto the target brain due to the removal of background activity. When cerebral glucose metabolism of deaf cats were compared to the normal controls after removing the effects of the global count, the glucose metabolism in the auditory cortex, head of caudate nucleus, and thalamus in both hemispheres of the deaf cats was significantly lower than that of the controls (P<0.01). No area showed a significantly increased metabolism in the deaf cats even in higher significance level (P<0.05). ROI analysis also showed significant reduction of glucose metabolism in the same region. This study established and confirmed a method for voxel-based analysis of animal PET data of cat brain, which showed high localization accuracy and specificity and was useful for examining the cerebral glucose metabolism in a cat cortical deafness model

  10. Voxel-Based Correlation between Coregistered Single-Photon Emission Computed Tomography and Dynamic Susceptibility Contrast Magnetic Resonance Imaging in Subjects with Suspected Alzheimer Disease

    Energy Technology Data Exchange (ETDEWEB)

    Cavallin, L.; Axelsson, R.; Wahlund, L.O.; Oeksengard, A.R.; Svensson, L.; Juhlin, P.; Wiberg, M. Kristoffersen; Frank, A. [Division of Radiology, Karolinska Inst., Karolinska Univ. Hospital, Stockholm (Sweden)

    2008-12-15

    Background: Current diagnosis of Alzheimer disease is made by clinical, neuropsychologic, and neuroimaging assessments. Neuroimaging techniques such as magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) could be valuable in the differential diagnosis of Alzheimer disease, as well as in assessing prognosis. Purpose: To compare SPECT and MRI in a cohort of patients examined for suspected dementia, including patients with no objective cognitive impairment (control group), mild cognitive impairment (MCI), and Alzheimer disease (AD). Material and Methods: 24 patients, eight with AD, 10 with MCI, and six controls, were investigated with SPECT using {sup 99m}Tc-hexamethylpropyleneamine oxime (HMPAO, Ceretec; GE Healthcare Ltd., Little Chalsont UK) and dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) with a contrast-enhancing gadobutrol formula (Gadovist; Bayer Schering Pharma, Berlin, Germany). Voxel-based correlation between coregistered SPECT and DSC-MR images was calculated. Region-of-interest (ROI) analyses were then performed in 24 different brain areas using brain registration and analysis of SPECT studies (BRASS; Nuclear Diagnostics AB, Stockholm (SE)) on both SPECT and DSC-MRI. Results: Voxel-based correlation between coregistered SPECT and DSC-MR showed a high correlation, with a mean correlation coefficient of 0.94. ROI analyses of 24 regions showed significant differences between the control group and AD patients in 10 regions using SPECT and five regions in DSC-MR. Conclusion: SPECT remains superior to DSC-MRI in differentiating normal from pathological perfusion, and DSC-MRI could not replace SPECT in the diagnosis of patients with Alzheimer disease.

  11. Voxel-Based Correlation between Coregistered Single-Photon Emission Computed Tomography and Dynamic Susceptibility Contrast Magnetic Resonance Imaging in Subjects with Suspected Alzheimer Disease

    Energy Technology Data Exchange (ETDEWEB)

    Cavallin, L.; Axelsson, R.; Wahlund, L.O.; Oeksengard, A.R.; Svensson, L.; Juhlin, P.; Wiberg, M. Kristoffersen; Frank, A. (Division of Radiology, Karolinska Inst., Karolinska Univ. Hospital, Stockholm (Sweden))

    2008-12-15

    Background: Current diagnosis of Alzheimer disease is made by clinical, neuropsychologic, and neuroimaging assessments. Neuroimaging techniques such as magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) could be valuable in the differential diagnosis of Alzheimer disease, as well as in assessing prognosis. Purpose: To compare SPECT and MRI in a cohort of patients examined for suspected dementia, including patients with no objective cognitive impairment (control group), mild cognitive impairment (MCI), and Alzheimer disease (AD). Material and Methods: 24 patients, eight with AD, 10 with MCI, and six controls, were investigated with SPECT using 99mTc-hexamethylpropyleneamine oxime (HMPAO, Ceretec; GE Healthcare Ltd., Little Chalsont UK) and dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) with a contrast-enhancing gadobutrol formula (Gadovist; Bayer Schering Pharma, Berlin, Germany). Voxel-based correlation between coregistered SPECT and DSC-MR images was calculated. Region-of-interest (ROI) analyses were then performed in 24 different brain areas using brain registration and analysis of SPECT studies (BRASS; Nuclear Diagnostics AB, Stockholm (Sweden)) on both SPECT and DSC-MRI. Results: Voxel-based correlation between coregistered SPECT and DSC-MR showed a high correlation, with a mean correlation coefficient of 0.94. ROI analyses of 24 regions showed significant differences between the control group and AD patients in 10 regions using SPECT and five regions in DSC-MR. Conclusion: SPECT remains superior to DSC-MRI in differentiating normal from pathological perfusion, and DSC-MRI could not replace SPECT in the diagnosis of patients with Alzheimer disease

  12. Voxel-Based Correlation between Coregistered Single-Photon Emission Computed Tomography and Dynamic Susceptibility Contrast Magnetic Resonance Imaging in Subjects with Suspected Alzheimer Disease

    International Nuclear Information System (INIS)

    Background: Current diagnosis of Alzheimer disease is made by clinical, neuropsychologic, and neuroimaging assessments. Neuroimaging techniques such as magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) could be valuable in the differential diagnosis of Alzheimer disease, as well as in assessing prognosis. Purpose: To compare SPECT and MRI in a cohort of patients examined for suspected dementia, including patients with no objective cognitive impairment (control group), mild cognitive impairment (MCI), and Alzheimer disease (AD). Material and Methods: 24 patients, eight with AD, 10 with MCI, and six controls, were investigated with SPECT using 99mTc-hexamethylpropyleneamine oxime (HMPAO, Ceretec; GE Healthcare Ltd., Little Chalsont UK) and dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) with a contrast-enhancing gadobutrol formula (Gadovist; Bayer Schering Pharma, Berlin, Germany). Voxel-based correlation between coregistered SPECT and DSC-MR images was calculated. Region-of-interest (ROI) analyses were then performed in 24 different brain areas using brain registration and analysis of SPECT studies (BRASS; Nuclear Diagnostics AB, Stockholm (SE)) on both SPECT and DSC-MRI. Results: Voxel-based correlation between coregistered SPECT and DSC-MR showed a high correlation, with a mean correlation coefficient of 0.94. ROI analyses of 24 regions showed significant differences between the control group and AD patients in 10 regions using SPECT and five regions in DSC-MR. Conclusion: SPECT remains superior to DSC-MRI in differentiating normal from pathological perfusion, and DSC-MRI could not replace SPECT in the diagnosis of patients with Alzheimer disease

  13. Comparison of spin-echo and gradient recalled echo T1 weighted MR images for quantitative voxel-based clinical brain research

    International Nuclear Information System (INIS)

    Full text: New methods to normalise inter-subject global variations in T1-weighted MR (TI w) signal levels have permitted their use in voxel based population studies of brain dysfunction. Here we address the question of whether a spin-echo (SE) or a gradient recalled echo (GRE) TI w sequence is better for this purpose. GRE images are commonly referred to as 3D MRL SE has superior signal/noise properties to GRE but is slower to acquire so that typical slice thicknesses are 3-5 mm compared to 1-2 mm for GRE. GRE has better grey/white matter contrast which should permit better spatial normalization. However, unlike SE, GRE is affected by subject-specific magnetic field inhomogeneities that distort the images. We acquired TI brain images for 25 chronic fatigue syndrome (CFS) patients and 25 normal controls (NC) with TRITE/flip-angle of 600 ms/l5 ms/90 deg for SE and 5.76 ms/1.9 ms/9 deg for GRE. For GRE, the magnetic field inhomogeneity related signal level distortions could be corrected, but not the spatial distortions. After spatial normalization we subjected them to voxel-based statistical analysis with adjustment for global signal level using the SPM5 package. Initially, the same spatial normalization deformations were applied to both SE and GRE after coregistering them. Although the SPM regressions of SE and GRE yielded similar spatial distributions of significance, the SE regressions were consistently statistically stronger. For example, in one strong regression, the corrected cluster P value was twenty times stronger (I.Oe-5 versus I.Oe-3). TI w SE have proved better than TI GRE images in quantitative analysis in a clinical research study. (author)

  14. Voxel based statistical analysis method for microPET studies to assess the cerebral glucose metabolism in cat deafness model: comparison to ROI based method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Su; Lee, Jae Sung; Park, Min Hyun; Lee, Jong Jin; Kang, Hye Jin; Lee, Hyo Jeong; Oh, Seung Ha; Kim, Chong Sun; Jung, June Key; Lee, Myung Chul; Lee, Dong Soo [Seoul National University College of Medicine, Seoul (Korea, Republic of); Lim, Sang Moo [KIRAMS, Seoul (Korea, Republic of)

    2005-07-01

    Imaging research on the brain of sensory-deprived cats using small animal PET scanner has gained interest since the abundant information about the sensory system of ths animal is available and close examination of the brain is possible due to larger size of its brain than mouse or rat. In this study, we have established the procedures for 3D voxel-based statistical analysis (SPM) of FDG PET image of cat brain, and confirmed using ROI based-method. FDG PET scans of 4 normal and 4 deaf cats were acquired for 30 minutes using microPET R4 scanner. Only the brain cortices were extracted using a masking and threshold method to facilitate spatial normalization. After spatial normalization and smoothing, 3D voxel-wise and ROI based t-test were performed to identify the regions with significant different FDG uptake between the normal and deaf cats. In ROI analysis, 26 ROIs were drawn on both hemispheres, and regional mean pixel value in each ROI was normalized to the global mean of the brain. Cat brains were spatially normalized well onto the target brain due to the removal of background activity. When cerebral glucose metabolism of deaf cats were compared to the normal controls after removing the effects of the global count, the glucose metabolism in the auditory cortex, head of caudate nucleus, and thalamus in both hemispheres of the deaf cats was significantly lower than that of the controls (P<0.01). No area showed a significantly increased metabolism in the deaf cats even in higher significance level (P<0.05). ROI analysis also showed significant reduction of glucose metabolism in the same region. This study established and confirmed a method for voxel-based analysis of animal PET data of cat brain, which showed high localization accuracy and specificity and was useful for examining the cerebral glucose metabolism in a cat cortical deafness model.

  15. The change of cerebral blood flow after heart transplantation in congestive heart failure: a voxel-based and automatic VOl analysis of Tc-99m ECD SPECT

    International Nuclear Information System (INIS)

    To investigate the change of global and regional cerebral blood flow after heart transplantation (HT) in congestive heart failure (CHF) patients. Twenty-one patients with CHF who underwent HT (45±12 yrs, M/F=19/2) and 10 healthy volunteers (39±13 yrs, M/F = 7/3) were prospectively included. All patients underwent echocardiography and radionuclide angiography including brain and aorta with brain SPECT which was performed after iv bolus injection of Tc-99m ECD (740MBq) before (175±253 days) and after (129±82 days) HT. Patients were divided into two groups according to the interval between HT and postoperative SPECT [early follow-up (f/u): 6 mo, n=7]. Global CBF (gCBF) of bilateral hemispheres were calculated by Patlak graphical analysis. Absolute rCBF map was obtained from brain SPECT by Lassen's correction algorithm. Age-corrected voxel-based analysis using SPM2 and automatic VOl analysis were performed to assess the rCBF change. Cardiac ejection fraction of all patients improved after HT (20.8%→64.0%). gCBF was reduced compared to normal before HT (35.7±3.9 vs. 49.1±3.0 ml/100g/min; p<0.001) and improved postoperatively (46.6±5.4, p<0.001). The preoperative gCBFs of early and late f/u group were not different (34.6±3.2 vs. 38.0±4.4, p=0.149) but postoperative gCBF (43.9±3.7) of late f/u group was higher than those (52.0±4.0) of early f/u group (p<0.001). On voxel-based analysis, preoperative rCBF was reduced in entire brain but most severely in bilateral superior and inferior frontal cortex, supplementary motor area, precuneus and anterior cingulum, compared to normals (uncorrected p<0.001). After HT, rCBF of these areas improved more significantly in late f/u group than in early f/u group but still lower than normals. Global CBF was significantly reduced in CHF patients and improved after HT. rCBFs of the frontal cortex, precuneus and cingulum were most severely reduced and slowly improved after HT compared to other brain regions

  16. The change of cerebral blood flow after heart transplantation in congestive heart failure: a voxel-based and automatic VOl analysis of Tc-99m ECD SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Hong, I. K.; Kim, J. J.; Lee, C. H.; Lim, K. C.; Moon, D. H.; Rhu, J. S.; Kim, J. S. [Asan Medical Center, Seoul (Korea, Republic of)

    2007-07-01

    To investigate the change of global and regional cerebral blood flow after heart transplantation (HT) in congestive heart failure (CHF) patients. Twenty-one patients with CHF who underwent HT (45{+-}12 yrs, M/F=19/2) and 10 healthy volunteers (39{+-}13 yrs, M/F = 7/3) were prospectively included. All patients underwent echocardiography and radionuclide angiography including brain and aorta with brain SPECT which was performed after iv bolus injection of Tc-99m ECD (740MBq) before (175{+-}253 days) and after (129{+-}82 days) HT. Patients were divided into two groups according to the interval between HT and postoperative SPECT [early follow-up (f/u): <6 mo, n=14; late f/u: >6 mo, n=7]. Global CBF (gCBF) of bilateral hemispheres were calculated by Patlak graphical analysis. Absolute rCBF map was obtained from brain SPECT by Lassen's correction algorithm. Age-corrected voxel-based analysis using SPM2 and automatic VOl analysis were performed to assess the rCBF change. Cardiac ejection fraction of all patients improved after HT (20.8%{yields}64.0%). gCBF was reduced compared to normal before HT (35.7{+-}3.9 vs. 49.1{+-}3.0 ml/100g/min; p<0.001) and improved postoperatively (46.6{+-}5.4, p<0.001). The preoperative gCBFs of early and late f/u group were not different (34.6{+-}3.2 vs. 38.0{+-}4.4, p=0.149) but postoperative gCBF (43.9{+-}3.7) of late f/u group was higher than those (52.0{+-}4.0) of early f/u group (p<0.001). On voxel-based analysis, preoperative rCBF was reduced in entire brain but most severely in bilateral superior and inferior frontal cortex, supplementary motor area, precuneus and anterior cingulum, compared to normals (uncorrected p<0.001). After HT, rCBF of these areas improved more significantly in late f/u group than in early f/u group but still lower than normals. Global CBF was significantly reduced in CHF patients and improved after HT. rCBFs of the frontal cortex, precuneus and cingulum were most severely reduced and slowly improved after

  17. Structural deficits in the emotion circuit and cerebellum are associated with depression, anxiety and cognitive dysfunction in methadone maintenance patients: a voxel-based morphometric study.

    Science.gov (United States)

    Lin, Wei-Che; Chou, Kun-Hsien; Chen, Hsiu-Ling; Huang, Chu-Chung; Lu, Cheng-Hsien; Li, Shau-Hsuan; Wang, Ya-Ling; Cheng, Yu-Fan; Lin, Ching-Po; Chen, Chien-Chih

    2012-02-28

    Heroin users on methadone maintenance treatment (MMT) have elevated rates of co-morbid depression and are associated with have higher relapse rates for substance abuse. Structural abnormalities in MMT patients have been reported, but their impact on clinical performance is unknown. We investigated differences in gray matter volume (GMV) between 27 MMT patients and 23 healthy controls with voxel-based morphometry, and we correlated findings in the patients with Beck Depression Inventory scores, Beck Anxiety Inventory scores, and diminished cognitive functioning. MMT patients exhibited higher emotional deficits than healthy subjects. There was significantly smaller GMV in multiple cortices, especially in the left inferior frontal gyrus and left cerebellar vermis in the MMT group. The smaller GMV in the pre-frontal cortices, left sub-callosal cingulate gyrus, left post-central gyrus, left insula, and right cerebellar declive correlated with higher depression scores. The smaller GMV in the pre-frontal cortices, left sub-callosal cingulate gyrus, and left postcentral gyrus also correlated with higher anxiety scores, while smaller GMV in the cerebellum and bilateral insula was associated with impaired performance on tests of executive function. These results reveal that MMT patients have low GMV in brain regions that are hypothesized to influence cognition and emotion, and the GMV findings might be involved comorbid disorders in the MMT group. PMID:22386968

  18. FKBP5 is associated with amygdala volume in the human brain and mood state: A voxel-based morphometry (VBM) study.

    Science.gov (United States)

    Hirakawa, Hirofumi; Akiyoshi, Jotaro; Muronaga, Masaaki; Tanaka, Yoshihiro; Ishitobi, Yoshinobu; Inoue, Ayako; Oshita, Harumi; Aizawa, Saeko; Masuda, Koji; Higuma, Haruka; Kanehisa, Masayuki; Ninomiya, Taiga; Kawano, Yoshihisa

    2016-06-01

    The present study was to investigate the effects of 6 FK506 binding protein 51 (FKBP5) single nucleotide polymorphisms (SNPs) on brain structure using voxel-based morphometry (VBM) and the psychological tests to psychological stress. We genotyped 112 healthy controls with respect to 6 SNPs (rs) of FKBP5. We examined the Beck Depression Inventory and the State (STAI-S) and Trait (STAI-T) versions of the Spielberger Anxiety Inventory and the Profile of Mood States (POMS) to evaluate mood. The right amygdala was larger in subjects with the minor allele (C) of rs3800373 and rs992105 and the minor allele (T) of rs1360780. The right middle orbitofrontal region in those with the minor allele (C) of rs3800373 and the right inferior orbitofrontal region in those with the minor allele (T) of rs9470080 was larger. Both the amygdala volumes were associated significantly with FKBP5 SNPs. We found significant relationships between factors in POMS and the right and left amygdala and left insula. Our results suggest that FKBP5 SNPs are associated with the alternations of volumes in right amygdala and the right middle and inferior orbitofrontal region. Genetic variants of FKBP5 may be associated with depressive and anxiety state via differential effects on amygdala and orbitofrontal region. PMID:26982819

  19. Radiation-induced changes in normal-appearing gray matter in patients with nasopharyngeal carcinoma: a magnetic resonance imaging voxel-based morphometry study

    International Nuclear Information System (INIS)

    Evidence is accumulating that temporal lobe radiation necrosis in patients with nasopharyngeal carcinoma (NPC) after radiotherapy (RT) could involve gray matter (GM). The purpose of the study was to assess the radiation-induced GM volume differences between NPC patients who had and had not received RT and the effect of time after RT on GM volume differences in those patients who had received RT. We used magnetic resonance imaging voxel-based morphometry (VBM) to assess differences in GM volume between 30 NPC patients with normal-appearing whole-brain GM after RT and 15 control patients with newly diagnosed but not yet medically treated NPC. Correlation analyses were used to investigate the relationship between GM volume changes and time after RT. Patients who had received RT had GM volume decreases in the bilateral superior temporal gyrus, left middle temporal gyrus, right fusiform gyrus, right precentral gyrus, and right inferior parietal lobule (p 100 voxels). Moreover, the correlation analysis indicated that regional GM volume loss in the left superior temporal gyrus, left middle temporal gyrus, and right fusiform gyrus were negatively related to the mean dose to the ipsilateral temporal lobe, respectively. These results indicate that GM volume deficits in bilateral temporal lobes in patients who had received RT might be radiation-induced. Our findings might provide new insight into the pathogenesis of radiation-induced structural damage in normal-appearing brain tissue. Yet this is an exploratory study, whose findings should therefore be taken with caution. (orig.)

  20. The efficacy of a voxel-based morphometry on the analysis of imaging in schizophrenia, temporal lobe epilepsy, and Alzheimer's disease/mild cognitive impairment: a review

    International Nuclear Information System (INIS)

    Voxel-based morphometry (VBM) done by means of MRI have provided new insights into the neuroanatomical basis for subjects with several conditions. Recently, VBM has been applied to investigate not only regional volumetric changes but also voxel-wise maps of fractional anisotropy (FA) computed from diffusion tensor imaging (DTI). The aim of this article is to review the recent work using VBM technique in particular focusing on schizophrenia, temporal lobe epilepsy (TLE), and Alzheimer's disease (AD)/mild cognitive impairment (MCI). In patients with schizophrenia, VBM approach detects the structural brain abnormalities that appear normal on conventional MRI. Moreover, this technique also has the potential to emerge as a useful clinical tool for early detection and monitoring of disease progression and treatment response in patients with schizophrenia or AD/MCI. In TLE, VBM approach may help elucidate some unresolved important research questions such as how recurrent temporal lobe seizures affect hippocampal and extrahippocampal morphology. Thus, in the future, large cohort studies to monitor whole brain changes on a VBM basis will lead to a further understanding of the neuropathology of several conditions. (orig.)

  1. Comparison of grey matter and metabolic reductions in frontotemporal dementia using FDG-PET and voxel-based morphometric MR studies

    Energy Technology Data Exchange (ETDEWEB)

    Kanda, Tomonori; Uemura, Takafumi; Miyamoto, Naokazu; Yoshikawa, Toshiki; Kono, Atsushi K. [Hyogo Brain and Heart Center, Department of Radiology and Nuclear Medicine, Himeji, Hyogo (Japan); Ishii, Kazunari [Hyogo Brain and Heart Center, Department of Radiology and Nuclear Medicine, Himeji, Hyogo (Japan); Hyogo Institute for Aging Brain and Cognitive Disorders, Division of Neuroimaging Research, Himeji, Hyogo (Japan); Mori, Etsuro [Hyogo Institute for Aging Brain and Cognitive Disorders, Division of Clinical Neurosciences, Himeji, Hyogo (Japan); Tohoku University Graduate School of Medicine, Behavioral Neurology and Cognitive Neuroscience, Sendai, Miyagi (Japan)

    2008-12-15

    The aim of this study was to investigate the regional differences between the morphologic and functional changes in the same patients with frontotemporal dementia (FTD) using statistical parametric mapping and voxel-based morphometry (VBM). Thirteen FTD patients (mean age, 64.9 years old; mean MMSE score, 17.7), 20 sex-matched Alzheimer's disease (AD) patients (mean age, 65.0 years old; mean MMSE score, 17.5), and 20 normal volunteers (mean age, 65.2 years old; mean MMSE score, 29.0) underwent both [{sup 18}F]FDG positron emission tomography and three-dimensional spoiled gradient echo MRI. Statistical parametric mapping was used to conduct a VBM analysis of the morphologic data, which were compared voxel by voxel with the results of a similar analysis of glucose metabolic data. FTD patients showed decreased grey matter volume and decreased glucose metabolism in the frontal lobe and anterior temporal lobe. In addition, there was a clear asymmetry in grey matter volume in FTD patients by the VBM analysis while the glucose metabolic data showed little asymmetry. In AD patients, glucose metabolic reduction occurred in the bilateral posterior cingulate gyri and parietal lobules while grey matter density decreased the least in the same patients. In FTD, metabolic and morphologic changes occur in the bilateral frontal lobe and temporal lobe with a limited asymmetry whereas there was considerable discordance in the AD group. (orig.)

  2. Examining brain structures associated with the motive to achieve success and the motive to avoid failure: A voxel-based morphometry study.

    Science.gov (United States)

    Ming, Dan; Chen, Qunlin; Yang, Wenjing; Chen, Rui; Wei, Dongtao; Li, Wenfu; Qiu, Jiang; Xu, Zhan; Zhang, Qinglin

    2016-01-01

    The motive to achieve success (MAS) and motive to avoid failure (MAF) are two different but classical kinds of achievement motivation. Though many functional magnetic resonance imaging studies have explored functional activation in motivation-related conditions, research has been silent as to the brain structures associated with individual differences in achievement motivation, especially with respect to MAS and MAF. In this study, the voxel-based morphometry method was used to uncover focal differences in brain structures related to MAS and MAF measured by the Mehrabian Achieving Tendency Scale in 353 healthy young Chinese adults. The results showed that the brain structures associated with individual differences in MAS and MAF were distinct. MAS was negatively correlated with regional gray matter volume (rGMV) in the medial prefrontal cortex (mPFC)/orbitofrontal cortex while MAF was negatively correlated with rGMV in the mPFC/subgenual cingulate gyrus. After controlling for mutual influences of MAS and MAF scores, MAS scores were found to be related to rGMV in the mPFC/orbitofrontal cortex and another cluster containing the parahippocampal gyrus and precuneus. These results may predict that compared with MAF, the generation process of MAS may be more complex and rational, thus in the real world, perhaps MAS is more beneficial to personal growth and guaranteeing the quality of task performance. PMID:25895120

  3. Comparison of grey matter and metabolic reductions in frontotemporal dementia using FDG-PET and voxel-based morphometric MR studies

    International Nuclear Information System (INIS)

    The aim of this study was to investigate the regional differences between the morphologic and functional changes in the same patients with frontotemporal dementia (FTD) using statistical parametric mapping and voxel-based morphometry (VBM). Thirteen FTD patients (mean age, 64.9 years old; mean MMSE score, 17.7), 20 sex-matched Alzheimer's disease (AD) patients (mean age, 65.0 years old; mean MMSE score, 17.5), and 20 normal volunteers (mean age, 65.2 years old; mean MMSE score, 29.0) underwent both [18F]FDG positron emission tomography and three-dimensional spoiled gradient echo MRI. Statistical parametric mapping was used to conduct a VBM analysis of the morphologic data, which were compared voxel by voxel with the results of a similar analysis of glucose metabolic data. FTD patients showed decreased grey matter volume and decreased glucose metabolism in the frontal lobe and anterior temporal lobe. In addition, there was a clear asymmetry in grey matter volume in FTD patients by the VBM analysis while the glucose metabolic data showed little asymmetry. In AD patients, glucose metabolic reduction occurred in the bilateral posterior cingulate gyri and parietal lobules while grey matter density decreased the least in the same patients. In FTD, metabolic and morphologic changes occur in the bilateral frontal lobe and temporal lobe with a limited asymmetry whereas there was considerable discordance in the AD group. (orig.)

  4. Patients with Poor Response to Antipsychotics Have a More Severe Pattern of Frontal Atrophy: A Voxel-Based Morphometry Study of Treatment Resistance in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Mario Quarantelli

    2014-01-01

    Full Text Available Approximately 30% of schizophrenia patients do not respond adequately to the therapy. Previous MRI studies have suggested that drug treatment resistance is associated with brain morphological abnormalities, although region-of-interest analysis of MR studies from nonresponder and responder patients failed to demonstrate a statistically significant difference between these two schizophrenia subgroups. We have used a voxel-based analysis of segmented MR studies to assess structural cerebral differences in 20 nonresponder and 15 responder patients and 16 age-matched normal volunteers. Differences between the three groups emerged bilaterally mainly at the level of the superior and middle frontal gyri, primarily due to reduced grey matter volumes in nonresponders, as compared to both normal volunteers and responder patients. Post hoc direct comparison between the two schizophrenia subgroups demonstrated significantly reduced grey matter volumes in middle frontal gyrus bilaterally, in the dorsolateral aspects of left superior frontal gyrus extending into postcentral gyrus and in the right medial temporal cortex. Our results extend and integrate previous findings suggesting a more severe atrophy in nonresponder schizophrenia patients, compared to responder patients, mainly at the level of the superior and middle frontal gyri. Longitudinal studies in drug-naïve patients are needed to assess the role of these associations.

  5. White Matter Atrophy in Patients with Mesial Temporal Lobe Epilepsy: Voxel-Based Morphometry Analysis of T1- and T2-Weighted MR Images

    Directory of Open Access Journals (Sweden)

    Barbara Braga

    2012-01-01

    Full Text Available Introduction. Mesial temporal lobe epilepsy (MTLE associated with hippocampal sclerosis is highly refractory to clinical treatment. MRI voxel-based morphometry (VBM of T1-weighted images has revealed a widespread pattern of gray matter (GM and white matter (WM atrophy in MTLE. Few studies have investigated the role of T2-weighted images in revealing WM atrophy using VBM. Objectives. To compare the results of WM atrophy between T1- and T2-weighted images through VBM. Methods. We selected 28 patients with left and 27 with right MTLE and 60 normal controls. We analyzed T1- and T2- weighted images with SPM8, using VBM/DARTEL algorithm to extract maps of GM and WM. The second level of SPM was used to investigate areas of WM atrophy among groups. Results. Both acquisitions showed bilateral widespread WM atrophy. T1-weighted images showed higher sensibility to detect areas of WM atrophy in both groups of MTLE. T2-weighted images also showed areas of WM atrophy in a more restricted pattern, but still bilateral and with a large area of superposition with T1-weighted images. Conclusions. In MTLE, T1-weighted images are more sensitive to detect subtle WM abnormalities using VBM, compared to T2 images, although both present a good superposition of statistical maps.

  6. The gray matter volume of the amygdala is correlated with the perception of melodic intervals: a voxel-based morphometry study.

    Directory of Open Access Journals (Sweden)

    Xueting Li

    Full Text Available Music is not simply a series of organized pitches, rhythms, and timbres, it is capable of evoking emotions. In the present study, voxel-based morphometry (VBM was employed to explore the neural basis that may link music to emotion. To do this, we identified the neuroanatomical correlates of the ability to extract pitch interval size in a music segment (i.e., interval perception in a large population of healthy young adults (N = 264. Behaviorally, we found that interval perception was correlated with daily emotional experiences, indicating the intrinsic link between music and emotion. Neurally, and as expected, we found that interval perception was positively correlated with the gray matter volume (GMV of the bilateral temporal cortex. More important, a larger GMV of the bilateral amygdala was associated with better interval perception, suggesting that the amygdala, which is the neural substrate of emotional processing, is also involved in music processing. In sum, our study provides one of first neuroanatomical evidence on the association between the amygdala and music, which contributes to our understanding of exactly how music evokes emotional responses.

  7. Structural changes induced by daily music listening in the recovering brain after middle cerebral artery stroke: a voxel-based morphometry study

    Directory of Open Access Journals (Sweden)

    Teppo eSärkämö

    2014-04-01

    Full Text Available Music is a highly complex and versatile stimulus for the brain that engages many temporal, frontal, parietal, cerebellar, and subcortical areas involved in auditory, cognitive, emotional, and motor processing. Regular musical activities have been shown to effectively enhance the structure and function of many brain areas, making music a potential tool also in neurological rehabilitation. In our previous randomized controlled study, we found that listening to music on a daily basis can improve cognitive recovery and improve mood after an acute middle cerebral artery (MCA stroke. Extending this study, a voxel-based morphometry (VBM analysis utilizing cost-function masking was performed on the acute and 6-month post-stroke stage structural MRI data of the patients (n = 49 who either listened to their favourite music (music group, n = 16 or verbal material (audio book group, n = 18 or did not receive any listening material (control group, n = 15 during the 6-month recovery period. Although all groups showed significant grey matter volume (GMV increases from the acute to the 6-month stage, there was a specific network of frontal areas [left and right superior frontal gyrus (SFG, right medial SFG] and limbic areas [left ventral / subgenual anterior cingulate cortex (SACC and right ventral striatum (VS] in patients with left hemisphere damage in which the GMV increases were larger in the music group than in the audio book and control groups. Moreover, the GM reorganization in the frontal areas correlated with enhanced recovery of verbal memory, focused attention, and language skills, whereas the GM reorganization in the SACC correlated with reduced negative mood. This study adds on previous results, showing that music listening after stroke not only enhances behavioural recovery, but also induces fine-grained neuroanatomical changes in the recovering brain.

  8. Using voxel-based morphometry to examine the relationship between regional brain volumes and memory performance in amnestic mild cognitive impairment

    Directory of Open Access Journals (Sweden)

    Patric eMeyer

    2013-07-01

    Full Text Available Alzheimer’s disease (AD is a slowly progressive neurodegenerative disorder, in which morphological alterations of brain tissue develop many years before the first neuropsychological and clinical changes occur. Among the first and most prominent symptoms are deficiencies of declarative memory functions. This stage of precursory symptoms to AD has been described as amnestic mild cognitive impairment (aMCI and is discussed as a potential AD prodrome. As therapy in the later stages of AD has been shown to be of limited impact, aMCI would be the key target for early intervention. For that purpose a comprehensive neuropsychological and anatomical characterization of this group is necessary. Previous neuropsychological investigations identified tests which are highly sensitive in diagnosing aMCI and very early AD. However, the sensitivity of those neuropsychological tests to the particular structural neuropathology in aMCI remains to be specified. To this end we investigated 25 patients with single-domain aMCI. All participants underwent extensive neuropsychological testing and anatomical scanning with structural magnetic resonance imaging. Voxel-based morphometry (VBM was performed to identify brain regions that show a significant correlation between regional brain volume and behavioral measures of memory and executive functioning. We found that performance in a variety of mnemonic tests was directly related to the integrity of the medial temporal lobe cortex (MTLC. Moreover, impairment of memory subfunctions in aMCI might be detected earlier than overt structural damage. By this, these findings contribute to the identification of cerebral structures associated with memory deficits in aMCI.

  9. Detecting damaged regions of cerebral white matter in the subacute phase after carbon monoxide poisoning using voxel-based analysis with diffusion tensor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, Shunrou; Nishimoto, Hideaki; Ogasawara, Kuniaki [Iwate Medical University, Department of Neurosurgery, Morioka (Japan); Beppu, Takaaki [Iwate Medical University, Department of Neurosurgery, Morioka (Japan); Iwate Medical University, Department of Hyperbaric Medicine, Morioka (Japan); Sanjo, Katsumi; Koeda, Atsuhiko [Iwate Medical University, Department of Psychiatry, Morioka (Japan); Mori, Kiyoshi [Iwate Prefectural Critical Care and Emergency Center, Department of Neurology, Morioka (Japan); Kudo, Kohsuke; Sasaki, Makoto [Iwate Medical University, Advanced Medical Research Center, Morioka (Japan)

    2012-07-15

    The present study aimed to detect the main regions of cerebral white matter (CWM) showing damage in the subacute phase for CO-poisoned patients with chronic neurological symptoms using voxel-based analysis (VBA) with diffusion tensor imaging (DTI). Subjects comprised 22 adult CO-poisoned patients and 16 age-matched healthy volunteers as controls. Patients were classified into patients with transient acute symptoms only (group A) and patients with chronic neurological symptoms (group S). In all patients, DTI covering the whole brain was performed with a 3.0-T magnetic resonance imaging system at 2 weeks after CO exposure. As procedures for VBA, all fractional anisotropy (FA) maps obtained from DTI were spatially normalized, and FA values for all voxels in the whole CWM on normalized FA maps were statistically compared among the two patient groups and controls. Voxels with significant differences in FA were detected at various regions in comparisons between groups S and A and between group S and controls. In these comparisons, more voxels were detected in deep CWM, including the centrum semiovale, than in other regions. A few voxels were detected between group A and controls. Absolute FA values in the centrum semiovale were significantly lower in group S than in group A or controls. VBA demonstrated that CO-poisoned patients with chronic neurological symptoms had already suffered damage to various CWM regions in the subacute phase. In these regions, the centrum semiovale was suggested to be the main region damaged in the subacute phase after CO inhalation. (orig.)

  10. The common traits of the ACC and PFC in anxiety disorders in the DSM-5: meta-analysis of voxel-based morphometry studies.

    Directory of Open Access Journals (Sweden)

    Jing Shang

    Full Text Available BACKGROUND: The core domains of social anxiety disorder (SAD, generalized anxiety disorder (GAD, panic disorder (PD with and without agoraphobia (GA, and specific phobia (SP are cognitive and physical symptoms that are related to the experience of fear and anxiety. It remains unclear whether these highly comorbid conditions that constitute the anxiety disorder subgroups of the Diagnostic and Statistical Manual for Mental Disorders--Fifth Edition (DSM-5 represent distinct disorders or alternative presentations of a single underlying pathology. METHODS: A systematic search of voxel-based morphometry (VBM studies of SAD, GAD, PD, GA, and SP was performed with an effect-size signed differential mapping (ES-SDM meta-analysis to estimate the clusters of significant gray matter differences between patients and controls. RESULTS: Twenty-four studies were eligible for inclusion in the meta-analysis. Reductions in the right anterior cingulate gyrus and the left inferior frontal gyrus gray matter volumes (GMVs were noted in patients with anxiety disorders when potential confounders, such as comorbid major depressive disorder (MDD, age, and antidepressant use were controlled for. We also demonstrated increased GMVs in the right dorsolateral prefrontal cortex (DLPFC in comorbid depression-anxiety (CDA, drug-naïve and adult patients. Furthermore, we identified a reduced left middle temporal gyrus and right precentral gyrus in anxiety patients without comorbid MDD. CONCLUSION: Our findings indicate that a reduced volume of the right ventral anterior cingulate gyrus and left inferior frontal gyrus is common in anxiety disorders and is independent of comorbid depression, medication use, and age. This generic effect supports the notion that the four types of anxiety disorders have a clear degree of overlap that may reflect shared etiological mechanisms. The results are consistent with neuroanatomical DLPFC models of physiological responses, such as worry and

  11. In vivo quantitative whole-brain diffusion tensor imaging analysis of APP/PS1 transgenic mice using voxel-based and atlas-based methods

    International Nuclear Information System (INIS)

    Diffusion tensor imaging (DTI) has been applied to characterize the pathological features of Alzheimer's disease (AD) in a mouse model, although little is known about whether these features are structure specific. Voxel-based analysis (VBA) and atlas-based analysis (ABA) are good complementary tools for whole-brain DTI analysis. The purpose of this study was to identify the spatial localization of disease-related pathology in an AD mouse model. VBA and ABA quantification were used for the whole-brain DTI analysis of nine APP/PS1 mice and wild-type (WT) controls. Multiple scalar measurements, including fractional anisotropy (FA), trace, axial diffusivity (DA), and radial diffusivity (DR), were investigated to capture the various types of pathology. The accuracy of the image transformation applied for VBA and ABA was evaluated by comparing manual and atlas-based structure delineation using kappa statistics. Following the MR examination, the brains of the animals were analyzed for microscopy. Extensive anatomical alterations were identified in APP/PS1 mice, in both the gray matter areas (neocortex, hippocampus, caudate putamen, thalamus, hypothalamus, claustrum, amygdala, and piriform cortex) and the white matter areas (corpus callosum/external capsule, cingulum, septum, internal capsule, fimbria, and optic tract), evidenced by an increase in FA or DA, or both, compared to WT mice (p 0.05). The histopathological changes in the gray matter areas were confirmed by microscopy studies. DTI did, however, demonstrate significant changes in white matter areas, where the difference was not apparent by qualitative observation of a single-slice histological specimen. This study demonstrated the structure-specific nature of pathological changes in APP/PS1 mouse, and also showed the feasibility of applying whole-brain analysis methods to the investigation of an AD mouse model. (orig.)

  12. The polymorphism of YWHAE, a gene encoding 14-3-3epsilon, and brain morphology in schizophrenia: a voxel-based morphometric study.

    Directory of Open Access Journals (Sweden)

    Mikio Kido

    Full Text Available BACKGROUND: YWHAE is a possible susceptibility gene for schizophrenia that encodes 14-3-3epsilon, a Disrupted-in-Schizophrenia 1 (DISC1-interacting molecule, but the effect of variation in its genotype on brain morphology remains largely unknown. METHODS: In this voxel-based morphometric magnetic resonance imaging study, we conducted whole-brain analyses regarding the effects of YWHAE single-nucleotide polymorphisms (SNPs (rs28365859, rs11655548, and rs9393 and DISC1 SNP (rs821616 on gray matter volume in a Japanese sample of 72 schizophrenia patients and 86 healthy controls. On the basis of a previous animal study, we also examined the effect of rs28365859 genotype specifically on hippocampal volume. RESULTS: Whole-brain analyses showed no significant genotype effect of these SNPs on gray matter volume in all subjects, but we found significant genotype-by-diagnosis interaction for rs28365859 in the left insula and right putamen. The protective C allele carriers of rs28365859 had a significantly larger left insula than the G homozygotes only for schizophrenia patients, while the controls with G allele homozygosity had a significantly larger right putamen than the C allele carriers. The C allele carriers had a larger right hippocampus than the G allele homozygotes in schizophrenia patients, but not in healthy controls. No significant interaction was found between rs28365859 and DISC1 SNP on gray matter volume. CONCLUSIONS: These different effects of the YWHAE (rs28365859 genotype on brain morphology in schizophrenia and healthy controls suggest that variation in its genotype might be, at least partly, related to the abnormal neurodevelopment, including in the limbic regions, reported in schizophrenia. Our results also suggest its specific role among YWHAE SNPs in the pathophysiology of schizophrenia.

  13. White and Gray Matter Volume Changes and Correlation with Visual Evoked Potential in Patients with Optic Neuritis: A Voxel-Based Morphometry Study.

    Science.gov (United States)

    Huang, Xin; Zhang, Qiang; Hu, Pei-Hong; Zhong, Yu-Lin; Zhang, Ying; Wei, Rong; Xu, Ting-Ting; Shao, Yi; fMRI Study Group, And Oculopathy

    2016-01-01

    BACKGROUND The aim of this study was to investigate potential morphological alterations of gray and white matter in patients with optic neuritis (ON) and their relationship with behavioral performance, using voxel-based morphometry (VBM). MATERIAL AND METHODS Twelve (4 males, 8 females) patients with ON and 12 (4 males, 8 females) age-, sex-, and education-matched healthy controls (HCs) underwent magnetic resonance imaging (MRI). Imaging data were analyzed using two-sample t tests to identify group differences in gray and white matter volume (GMV, WMV). Correlation analysis was used to explore relationships between observed GMV and WMV of different areas and visual evoked potential (VEP) in ON. RESULTS Compared with HCs, ON patients had: significantly decreased GMV in the left postcentral gyrus, left inferior frontal gyrus, left anterior cingulate, left and right middle frontal gyrus, and right inferior parietal lobule; decreased WMV in the left middle frontal gyrus, right superior frontal gyrus, left precentral gyrus and right inferior parietal lobule; and increased WMV in the left fusiform gyrus and left inferior parietal lobule. VEP latency of the right eye in ON correlated positively with WMV signal value of the left fusiform gyrus (r=0.726, p=0.008), and negatively with GMV signal value of the right inferior parietal lobule (r=-0.611, p=0.035). Duration of ON correlated negatively with WMV signal value of the right superior frontal gyrus (r=-0.662, p=0.019), while best-corrected visual acuity (VA) of the right eye correlated negatively with WMV signal value of the left middle frontal gyrus (r=-0.704, p=0.011). CONCLUSIONS These results suggest significant brain involvement in ON, which may reflect the underlying pathologic mechanism. Correlational results demonstrate that VEP in ON is closely associated with WMV and GMV atrophy in many brain regions. PMID:27045330

  14. Radiation-induced changes in normal-appearing gray matter in patients with nasopharyngeal carcinoma: a magnetic resonance imaging voxel-based morphometry study

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Xiao-Fei; Zheng, Xiao-Li; Zhang, Wei-Dong; Liu, Li-Zhi; Zhang, You-Ming [State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou (China); Sun Yat-sen University Cancer Center, Department of Medical Imaging and Interventional Radiology, Guangzhou (China); Chen, Ming-Yuan [Sun Yat-sen University Cancer Center, Department of Nasopharyngeal Carcinoma, Guangzhou (China); Li, Li [Sun Yat-sen University Cancer Center, Department of Medical Imaging and Interventional Radiology, Guangzhou (China)

    2014-05-15

    Evidence is accumulating that temporal lobe radiation necrosis in patients with nasopharyngeal carcinoma (NPC) after radiotherapy (RT) could involve gray matter (GM). The purpose of the study was to assess the radiation-induced GM volume differences between NPC patients who had and had not received RT and the effect of time after RT on GM volume differences in those patients who had received RT. We used magnetic resonance imaging voxel-based morphometry (VBM) to assess differences in GM volume between 30 NPC patients with normal-appearing whole-brain GM after RT and 15 control patients with newly diagnosed but not yet medically treated NPC. Correlation analyses were used to investigate the relationship between GM volume changes and time after RT. Patients who had received RT had GM volume decreases in the bilateral superior temporal gyrus, left middle temporal gyrus, right fusiform gyrus, right precentral gyrus, and right inferior parietal lobule (p < 0.001, uncorrected, cluster size >100 voxels). Moreover, the correlation analysis indicated that regional GM volume loss in the left superior temporal gyrus, left middle temporal gyrus, and right fusiform gyrus were negatively related to the mean dose to the ipsilateral temporal lobe, respectively. These results indicate that GM volume deficits in bilateral temporal lobes in patients who had received RT might be radiation-induced. Our findings might provide new insight into the pathogenesis of radiation-induced structural damage in normal-appearing brain tissue. Yet this is an exploratory study, whose findings should therefore be taken with caution. (orig.)

  15. Clinical Study White Matter Atrophy in Patients with Mesial Temporal Lobe Epilepsy: Voxel-Based Morphometry Analysis of T1- and T2-Weighted MR Images

    International Nuclear Information System (INIS)

    Introduction. Mesial temporal lobe epilepsy (MTLE) associated with hippocampal sclerosis is highly refractory to clinical treatment. MRI voxel-based morphometry (VBM) of T1-weighted images has revealed a widespread pattern of gray matter (GM) and white matter (WM) atrophy in MTLE. Few studies have investigated the role of T2-weighted images in revealing WM atrophy using VBM. Objectives. To compare the results of WM atrophy between T1- and T2-weighted images through VBM. Methods. We selected 28 patients with left and 27 with right MTLE and 60 normal controls. We analyzed T1- and T2- weighted images with SPM8, using VBM/DARTEL algorithm to extract maps of GM and WM. The second level of SPM was used to investigate areas of WM atrophy among groups. Results. Both acquisitions showed bilateral widespread WM atrophy. T1-weighted images showed higher sensibility to detect areas of WM atrophy in both groups of MTLE. T2-weighted images also showed areas of WM atrophy in a more restricted pattern, but still bilateral and with a large area of superposition with T1-weighted images. Conclusions. In MTLE, T1-weighted images are more sensitive to detect subtle WM abnormalities using VBM, compared to T2 images, although both present a good superposition of statistical maps. 1. Introduction The mesial temporal lobe epilepsy (MTLE) is highly refractory to pharmacological treatment [1], and it is the main group of epilepsy referred to the tertiary care hospitals for surgical treatment [2]. MTLE shows a good surgical prognosis, with satisfactory seizures control in 60-80% of the patients [3]. In approximately 65%

  16. Greater intake of vitamins B6 and B12 spares gray matter in healthy elderly: a voxel-based morphometry study.

    Science.gov (United States)

    Erickson, Kirk I; Suever, Barbara L; Prakash, Ruchika Shaurya; Colcombe, Stanley J; McAuley, Edward; Kramer, Arthur F

    2008-03-14

    Previous studies have reported that high concentrations of homocysteine and lower concentrations of vitamins B6, B12, and folate increase the risk for cognitive decline and pathology in aging populations. In this cross-sectional study, high resolution magnetic resonance imaging (MRI) scans and a 3-day food diary were collected on 32 community-dwelling adults between the ages of 59 and 79. We examined the relation between vitamins B6, B12, and folate intake on cortical volume using an optimized voxel-based morphometry (VBM) method and global gray and white matter volume after correcting for age, sex, body mass index, calorie intake, and education. All participants met or surpassed the recommended daily intake for these vitamins. In the VBM analysis, we found that adults with greater vitamin B6 intake had greater gray matter volume along the medial wall, anterior cingulate cortex, medial parietal cortex, middle temporal gyrus, and superior frontal gyrus, whereas people with greater B12 intake had greater volume in the left and right superior parietal sulcus. These effects were driven by vitamin supplementation and were negated when only examining vitamin intake from diet. Folate had no effect on brain volume. Furthermore, there was no relationship between vitamins B6, B12, or folate intake on global brain volume measures, indicating that VBM methods are more sensitive for detecting localized differences in gray matter volume than global measures. These results are discussed in relation to a growing literature on vitamin intake on age-related neurocognitive deterioration. PMID:18281020

  17. Effects of Omega-3 Fatty Acid Supplementation on Cognitive Functions and Neural Substrates: A Voxel-Based Morphometry Study in Aged Mice.

    Science.gov (United States)

    Cutuli, Debora; Pagani, Marco; Caporali, Paola; Galbusera, Alberto; Laricchiuta, Daniela; Foti, Francesca; Neri, Cristina; Spalletta, Gianfranco; Caltagirone, Carlo; Petrosini, Laura; Gozzi, Alessandro

    2016-01-01

    Human and experimental studies have revealed putative neuroprotective and pro-cognitive effects of omega-3 polyunsaturated fatty acids (n-3 PUFA) in aging, evidencing positive correlations between peripheral n-3 PUFA levels and regional grey matter (GM) volume, as well as negative correlations between dietary n-3 PUFA levels and cognitive deficits. We recently showed that n-3 PUFA supplemented aged mice exhibit better hippocampal-dependent mnesic functions, along with enhanced cellular plasticity and reduced neurodegeneration, thus supporting a role of n-3 PUFA supplementation in preventing cognitive decline during aging. To corroborate these initial results and develop new evidence on the effects of n-3 PUFA supplementation on brain substrates at macro-scale level, here we expanded behavioral analyses to the emotional domain (anxiety and coping skills), and carried out a fine-grained regional GM volumetric mapping by using high-resolution MRI-based voxel-based morphometry. The behavioral effects of 8 week n-3 PUFA supplementation were measured on cognitive (discriminative, spatial and social) and emotional (anxiety and coping) abilities of aged (19 month-old at the onset of study) C57B6/J mice. n-3 PUFA supplemented mice showed better mnesic performances as well as increased active coping skills. Importantly, these effects were associated with enlarged regional hippocampal, retrosplenial and prefrontal GM volumes, and with increased post mortem n-3 PUFA brain levels. These findings indicate that increased dietary n-3 PUFA intake in normal aging can improve fronto-hippocampal GM structure and function, an effect present also when the supplementation starts at late age. Our data are consistent with a protective role of n-3 PUFA supplementation in counteracting cognitive decline, emotional dysfunctions and brain atrophy. PMID:26973513

  18. Cortico-striato-thalamo-cortical circuit abnormalities in obsessive-compulsive disorder: A voxel-based morphometric and fMRI study of the whole brain.

    Science.gov (United States)

    Tang, Wenxin; Zhu, Qifeng; Gong, Xiangyang; Zhu, Cheng; Wang, Yiquan; Chen, Shulin

    2016-10-15

    The primary aim of this study was to identify structural and functional abnormalities in the brains of obsessive-compulsive disorder (OCD) patients. Another aim was to assess the effect of serotonin selective reuptake inhibitors (SSRIs) on brain structure of OCD patients. All subjects underwent brain magnetic resonance imaging (MRI) and resting functional MRI (fMRI). High-resolution three-dimensional images were processed using the voxel-based morphometry (VBM) method. The final analysis included 18 OCD patients and 16 healthy controls. In the OCD patients there was a decrease in gray matter volume in the bilateral cingulate cortex and bilateral striatum. In some cortical structures including the cerebellar anterior lobe, left orbital frontal gyrus, right middle frontal gyrus, left middle temporal gyrus, precentral gyrus, and postcentral gyrus, there was an increase in gray matter volume. On fMRI the OCD patients had overactivation of the right cerebellum and right parietal lobe and reduced activation of the left cingulate gyrus, putamen, and caudate nucleus. Eleven OCD patients who improved during 12 weeks of drug treatment with sertraline hydrochloride had a significant increase in gray matter volume in several brain structures but no significant differences were found on resting fMRI. The results indicated a consistent trend between structural and functional images. Higher cortical structures showed increased gray matter volume and increased activation as did the cerebellum whereas subcortical structures showed decreased gray matter volume and decreased activation. And brain structure improvement consisted with symptom improvement after SSRIs treatment in OCD patients. PMID:27388149

  19. Brain Tissue Volumes and Perfusion Change with the Number of Optic Neuritis Attacks in Relapsing Neuromyelitis Optica: A Voxel-Based Correlation Study.

    Directory of Open Access Journals (Sweden)

    Carlos A Sánchez-Catasús

    Full Text Available Recent neuroimaging studies show that brain abnormalities in neuromyelitis optica (NMO are more frequent than earlier described. Yet, more research considering multiple aspects of NMO is necessary to better understand these abnormalities. A clinical feature of relapsing NMO (RNMO is that the incremental disability is attack-related. Therefore, association between the attack-related process and neuroimaging might be expected. On the other hand, the immunopathological analysis of NMO lesions has suggested that CNS microvasculature could be an early disease target, which could alter brain perfusion. Brain tissue volume changes accompanying perfusion alteration could also be expected throughout the attack-related process. The aim of this study was to investigate in RNMO patients, by voxel-based correlation analysis, the assumed associations between regional brain white (WMV and grey matter volumes (GMV and/or perfusion on one side, and the number of optic neuritis (ON attacks, myelitis attacks and/or total attacks on the other side. For this purpose, high resolution T1-weighted MRI and perfusion SPECT imaging were obtained in 15 RNMO patients. The results showed negative regional correlations of WMV, GMV and perfusion with the number of ON attacks, involving important components of the visual system, which could be relevant for the comprehension of incremental visual disability in RNMO. We also found positive regional correlation of perfusion with the number of ON attacks, mostly overlapping the brain area where the WMV showed negative correlation. This provides evidence that brain microvasculature is an early disease target and suggests that perfusion alteration could be important in the development of brain structural abnormalities in RNMO.

  20. The effect of hepatic encephalopathy, hepatic failure, and portosystemic shunt on brain volume of cirrhotic patients: a voxel-based morphometry study.

    Directory of Open Access Journals (Sweden)

    Long Jiang Zhang

    Full Text Available PURPOSE: To evaluate the effect of hepatic encephalopathy (HE, hepatic failure, and portosystemic shunt (PS on the brain volume alteration in cirrhotic patients with MRI voxel-based morphometry (VBM. METHODS: Sixty cirrhotic patients (overt HE [OHE], n = 11; minimal HE [MHE], n = 19; non HE [nHE], n = 30 including 12 with pre- and post-transjugular intrahepatic portosystemic shunt (TIPS scanning and 40 healthy controls were recruited. Neuropsychological and laboratory tests were performed in all patients. VBM was analyzed with ANOVA test among 4 groups, and t-tests for patients with different hepatic function, PS scores, and TIPS. Multiple linear regression was performed to investigate the effect of venous blood ammonia levels, Child-Pugh scores, and PS on the brain volumes in all patients. RESULTS: Cirrhotic patients exhibited decreased volume in many areas of gray matter (GM, increased volume in thalamus, and increased whiter matter (WM volume, with the extent of affected brain volume greater in HE patients than nHE patients. Hepatic failure also resulted in decreased GM volume. Patients with high PS scores and TIPS displayed decreased GM and increased WM volume in some regions. Post-TIPS patients displayed increased GM volume in the thalamus. Multiple covariate regression results suggested that Child-Pugh score was a major factor to affect GM volume, while PS mainly affected WM volume. CONCLUSION: Brain structure abnormalities appeared bilaterally symmetrical in cirrhotic patients, and the impairment was more extensive in HE patients than those without HE. Increased thalamus volume was not associated with HE progression. Hepatic failure and PS altered cirrhotic patients' brain structure.

  1. Detecting damaged regions of cerebral white matter in the subacute phase after carbon monoxide poisoning using voxel-based analysis with diffusion tensor imaging

    International Nuclear Information System (INIS)

    The present study aimed to detect the main regions of cerebral white matter (CWM) showing damage in the subacute phase for CO-poisoned patients with chronic neurological symptoms using voxel-based analysis (VBA) with diffusion tensor imaging (DTI). Subjects comprised 22 adult CO-poisoned patients and 16 age-matched healthy volunteers as controls. Patients were classified into patients with transient acute symptoms only (group A) and patients with chronic neurological symptoms (group S). In all patients, DTI covering the whole brain was performed with a 3.0-T magnetic resonance imaging system at 2 weeks after CO exposure. As procedures for VBA, all fractional anisotropy (FA) maps obtained from DTI were spatially normalized, and FA values for all voxels in the whole CWM on normalized FA maps were statistically compared among the two patient groups and controls. Voxels with significant differences in FA were detected at various regions in comparisons between groups S and A and between group S and controls. In these comparisons, more voxels were detected in deep CWM, including the centrum semiovale, than in other regions. A few voxels were detected between group A and controls. Absolute FA values in the centrum semiovale were significantly lower in group S than in group A or controls. VBA demonstrated that CO-poisoned patients with chronic neurological symptoms had already suffered damage to various CWM regions in the subacute phase. In these regions, the centrum semiovale was suggested to be the main region damaged in the subacute phase after CO inhalation. (orig.)

  2. Application of Voxel-Based Morphometry in Mild Cognitive Impairment and Alzheimer's Disease%基于体素的形态学测量技术在轻度认知障碍和Alzheimer病中的应用

    Institute of Scientific and Technical Information of China (English)

    秦锦标; 杨明华

    2008-01-01

    基于体素的形态学测量技术(VBM)是近年来发展起来的一种新型脑形态学测量技术,文章简要阐述了VBM的概念、基本原理和优缺点,同时对其在轻度认知障碍和Alzheimer病中的初步应用做了综述.%Tne voxel-based morphometry(VBM)is a newly developed technique for brain morphometry in recent years.This article briefly expounds the concept,fundamental principle, advantages and disadvantages of VBM.It also reviews the preliminary applications of voxel-based morphometry in mild cognitive impairment and Alzheimer'S disease.

  3. Correlations between FDG PET glucose uptake-MRI gray matter volume scores and apolipoprotein E ε4 gene dose in cognitively normal adults: a cross-validation study using voxel-based multi-modal partial least squares

    OpenAIRE

    Chen, Kewei; Ayutyanont, Napatkamon; Langbaum, Jessica B. S.; Fleisher, Adam S.; Reschke, Cole; Lee, Wendy; Liu, Xiaofen; Alexander, Gene E; Bandy, Dan; Caselli, Richard J.; Reiman, Eric M

    2012-01-01

    We previously introduced a voxel-based, multi-modal application of the partial least square algorithm (MMPLS) to characterize the linkage between patterns in a person’s complementary complex datasets without the need to correct for multiple regional comparisons. Here we used it to demonstrate a strong correlation between MMPLS scores to characterize the linkage between the covarying patterns of fluorodeoxyglucose positron emission tomography (FDG PET) measurements of regional glucose metaboli...

  4. Simplifying Massive Contour Maps

    DEFF Research Database (Denmark)

    Arge, Lars; Deleuran, Lasse Kosetski; Mølhave, Thomas; Revsbæk, Morten; Truelsen, Jakob

    2012-01-01

    We present a simple, efficient and practical algorithm for constructing and subsequently simplifying contour maps from massive high-resolution DEMs, under some practically realistic assumptions on the DEM and contours.......We present a simple, efficient and practical algorithm for constructing and subsequently simplifying contour maps from massive high-resolution DEMs, under some practically realistic assumptions on the DEM and contours....

  5. Design, fabrication, and implementation of voxel-based 3D printed textured phantoms for task-based image quality assessment in CT

    Science.gov (United States)

    Solomon, Justin; Ba, Alexandre; Diao, Andrew; Lo, Joseph; Bier, Elianna; Bochud, François; Gehm, Michael; Samei, Ehsan

    2016-03-01

    In x-ray computed tomography (CT), task-based image quality studies are typically performed using uniform background phantoms with low-contrast signals. Such studies may have limited clinical relevancy for modern non-linear CT systems due to possible influence of background texture on image quality. The purpose of this study was to design and implement anatomically informed textured phantoms for task-based assessment of low-contrast detection. Liver volumes were segmented from 23 abdominal CT cases. The volumes were characterized in terms of texture features from gray-level co-occurrence and run-length matrices. Using a 3D clustered lumpy background (CLB) model, a fitting technique based on a genetic optimization algorithm was used to find the CLB parameters that were most reflective of the liver textures, accounting for CT system factors of spatial blurring and noise. With the modeled background texture as a guide, a cylinder phantom (165 mm in diameter and 30 mm height) was designed, containing 20 low-contrast spherical signals (6 mm in diameter at targeted contrast levels of ~3.2, 5.2, 7.2, 10, and 14 HU, 4 repeats per signal). The phantom was voxelized and input into a commercial multi-material 3D printer (Object Connex 350), with custom software for voxel-based printing. Using principles of digital half-toning and dithering, the 3D printer was programmed to distribute two base materials (VeroWhite and TangoPlus, nominal voxel size of 42x84x30 microns) to achieve the targeted spatial distribution of x-ray attenuation properties. The phantom was used for task-based image quality assessment of a clinically available iterative reconstruction algorithm (Sinogram Affirmed Iterative Reconstruction, SAFIRE) using a channelized Hotelling observer paradigm. Images of the textured phantom and a corresponding uniform phantom were acquired at six dose levels and observer model performance was estimated for each condition (5 contrasts x 6 doses x 2 reconstructions x 2

  6. In vivo quantitative whole-brain diffusion tensor imaging analysis of APP/PS1 transgenic mice using voxel-based and atlas-based methods

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Yuan-Yuan [Huazhong University of Science and Technology, Department of Radiology, Tongji Hospital, Tongji Medical College, Wuhan (China); The Johns Hopkins University School of Medicine, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Li, Mu-Wei; Oishi, Kenichi [The Johns Hopkins University School of Medicine, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Zhang, Shun; Zhang, Yan; Zhao, Ling-Yun; Zhu, Wen-Zhen [Huazhong University of Science and Technology, Department of Radiology, Tongji Hospital, Tongji Medical College, Wuhan (China); Lei, Hao [Chinese Academy of Sciences, Wuhan Center for Magnetic Resonance, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Wuhan (China)

    2013-08-15

    Diffusion tensor imaging (DTI) has been applied to characterize the pathological features of Alzheimer's disease (AD) in a mouse model, although little is known about whether these features are structure specific. Voxel-based analysis (VBA) and atlas-based analysis (ABA) are good complementary tools for whole-brain DTI analysis. The purpose of this study was to identify the spatial localization of disease-related pathology in an AD mouse model. VBA and ABA quantification were used for the whole-brain DTI analysis of nine APP/PS1 mice and wild-type (WT) controls. Multiple scalar measurements, including fractional anisotropy (FA), trace, axial diffusivity (DA), and radial diffusivity (DR), were investigated to capture the various types of pathology. The accuracy of the image transformation applied for VBA and ABA was evaluated by comparing manual and atlas-based structure delineation using kappa statistics. Following the MR examination, the brains of the animals were analyzed for microscopy. Extensive anatomical alterations were identified in APP/PS1 mice, in both the gray matter areas (neocortex, hippocampus, caudate putamen, thalamus, hypothalamus, claustrum, amygdala, and piriform cortex) and the white matter areas (corpus callosum/external capsule, cingulum, septum, internal capsule, fimbria, and optic tract), evidenced by an increase in FA or DA, or both, compared to WT mice (p < 0.05, corrected). The average kappa value between manual and atlas-based structure delineation was approximately 0.8, and there was no significant difference between APP/PS1 and WT mice (p > 0.05). The histopathological changes in the gray matter areas were confirmed by microscopy studies. DTI did, however, demonstrate significant changes in white matter areas, where the difference was not apparent by qualitative observation of a single-slice histological specimen. This study demonstrated the structure-specific nature of pathological changes in APP/PS1 mouse, and also showed the

  7. When the Single Matters more than the Group (II): Addressing the Problem of High False Positive Rates in Single Case Voxel Based Morphometry Using Non-parametric Statistics.

    Science.gov (United States)

    Scarpazza, Cristina; Nichols, Thomas E; Seramondi, Donato; Maumet, Camille; Sartori, Giuseppe; Mechelli, Andrea

    2016-01-01

    In recent years, an increasing number of studies have used Voxel Based Morphometry (VBM) to compare a single patient with a psychiatric or neurological condition of interest against a group of healthy controls. However, the validity of this approach critically relies on the assumption that the single patient is drawn from a hypothetical population with a normal distribution and variance equal to that of the control group. In a previous investigation, we demonstrated that family-wise false positive error rate (i.e., the proportion of statistical comparisons yielding at least one false positive) in single case VBM are much higher than expected (Scarpazza et al., 2013). Here, we examine whether the use of non-parametric statistics, which does not rely on the assumptions of normal distribution and equal variance, would enable the investigation of single subjects with good control of false positive risk. We empirically estimated false positive rates (FPRs) in single case non-parametric VBM, by performing 400 statistical comparisons between a single disease-free individual and a group of 100 disease-free controls. The impact of smoothing (4, 8, and 12 mm) and type of pre-processing (Modulated, Unmodulated) was also examined, as these factors have been found to influence FPRs in previous investigations using parametric statistics. The 400 statistical comparisons were repeated using two independent, freely available data sets in order to maximize the generalizability of the results. We found that the family-wise error rate was 5% for increases and 3.6% for decreases in one data set; and 5.6% for increases and 6.3% for decreases in the other data set (5% nominal). Further, these results were not dependent on the level of smoothing and modulation. Therefore, the present study provides empirical evidence that single case VBM studies with non-parametric statistics are not susceptible to high false positive rates. The critical implication of this finding is that VBM can be used

  8. FWS Interest Simplified

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These boundaries are simplified from the U.S. Fish and Wildlife Service Real Estate Interest data layer containing polygons representing tracts of land (parcels) in...

  9. Age and gender effects on normal regional cerebral blood flow studied using two different voxel-based statistical analyses; Effets de l'age et du genre sur la perfusion cerebrale regionale etudiee par deux methodes d'analyse statistique voxel-par-voxel

    Energy Technology Data Exchange (ETDEWEB)

    Pirson, A.S.; George, J.; Krug, B.; Vander Borght, T. [Universite Catholique de Louvain, Service de Medecine Nucleaire, Cliniques Universitaires de Mont-Godinne, Yvoir (Belgium); Van Laere, K. [Leuven Univ. Hospital, Nuclear Medicine Div. (Belgium); Jamart, J. [Universite Catholique de Louvain, Dept. de Biostatistiques, Cliniques Universitaires de Mont-Godinne, Yvoir (Belgium); D' Asseler, Y. [Ghent Univ., Medical Signal and Image Processing Dept. (MEDISIP), Faculty of applied sciences (Belgium); Minoshima, S. [Washington Univ., Dept. of Radiology, Seattle (United States)

    2009-10-15

    Fully automated analysis programs have been applied more and more to aid for the reading of regional cerebral blood flow SPECT study. They are increasingly based on the comparison of the patient study with a normal database. In this study, we evaluate the ability of Three-Dimensional Stereotactic Surface Projection (3 D-S.S.P.) to isolate effects of age and gender in a previously studied normal population. The results were also compared with those obtained using Statistical Parametric Mapping (S.P.M.99). Methods Eighty-nine {sup 99m}Tc-E.C.D.-SPECT studies performed in carefully screened healthy volunteers (46 females, 43 males; age 20 - 81 years) were analysed using 3 D-S.S.P.. A multivariate analysis based on the general linear model was performed with regions as intra-subject factor, gender as inter-subject factor and age as co-variate. Results Both age and gender had a significant interaction effect with regional tracer uptake. An age-related decline (p < 0.001) was found in the anterior cingulate gyrus, left frontal association cortex and left insula. Bilateral occipital association and left primary visual cortical uptake showed a significant relative increase with age (p < 0.001). Concerning the gender effect, women showed higher uptake (p < 0.01) in the parietal and right sensorimotor cortices. An age by gender interaction (p < 0.01) was only found in the left medial frontal cortex. The results were consistent with those obtained with S.P.M.99. Conclusion 3 D-S.S.P. analysis of normal r.C.B.F. variability is consistent with the literature and other automated voxel-based techniques, which highlight the effects of both age and gender. (authors)

  10. 78 FR 44142 - Modification of Two National Customs Automation Program (NCAP) Tests Concerning Automated...

    Science.gov (United States)

    2013-07-23

    ... Automation Program (NCAP) test called the Document Image System (DIS) test. See 77 FR 20835. The DIS test... Automation Program Test of Automated Manifest Capabilities for Ocean and Rail Carriers: 76 FR 42721 (July 19... (SE test). See 76 FR 69755. The SE test established new entry capability to simplify the entry......

  11. 77 FR 48527 - National Customs Automation Program (NCAP) Test Concerning Automated Commercial Environment (ACE...

    Science.gov (United States)

    2012-08-14

    ... SECURITY U.S. Customs and Border Protection National Customs Automation Program (NCAP) Test Concerning...) National Customs Automation Program (NCAP) test concerning Automated Commercial Environment (ACE... Simplified Entry were announced in a notice published in the Federal Register on November 9, 2011 (76...

  12. Simplifying EU environmental legislation

    DEFF Research Database (Denmark)

    Anker, Helle Tegner

    2014-01-01

    The recent review of the EIA Directive was launched as part of the ‘better regulation’ agenda with the purpose to simplify procedures and reduce administrative burdens. This was combined with an attempt to further harmonise procedures in order address shortcomings in the Directive and to overcome...

  13. Simplifying gene trees for easier comprehension

    Directory of Open Access Journals (Sweden)

    Mundry Marvin

    2006-04-01

    Full Text Available Abstract Background In the genomic age, gene trees may contain large amounts of data making them hard to read and understand. Therefore, an automated simplification is important. Results We present a simplification tool for gene trees called TreeSimplifier. Based on species tree information and HUGO gene names, it summarizes "monophyla". These monophyla correspond to subtrees of the gene tree where the evolution of a gene follows species phylogeny, and they are simplified to single leaves in the gene tree. Such a simplification may fail, for example, due to genes in the gene tree that are misplaced. In this way, misplaced genes can be identified. Optionally, our tool glosses over a limited degree of "paraphyly" in a further simplification step. In both simplification steps, species can be summarized into groups and treated as equivalent. In the present study we used our tool to derive a simplified tree of 397 leaves from a tree of 1138 leaves. Comparing the simplified tree to a "cartoon tree" created manually, we note that both agree to a high degree. Conclusion Our automatic simplification tool for gene trees is fast, accurate, and effective. It yields results of similar quality as manual simplification. It should be valuable in phylogenetic studies of large protein families. The software is available at http://www.uni-muenster.de/Bioinformatics/services/treesim/.

  14. The simplified models approach to constraining supersymmetry

    Energy Technology Data Exchange (ETDEWEB)

    Perez, Genessis [Institut fuer Theoretische Physik, Karlsruher Institut fuer Technologie (KIT), Wolfgang-Gaede-Str. 1, 76131 Karlsruhe (Germany); Kulkarni, Suchita [Laboratoire de Physique Subatomique et de Cosmologie, Universite Grenoble Alpes, CNRS IN2P3, 53 Avenue des Martyrs, 38026 Grenoble (France)

    2015-07-01

    The interpretation of the experimental results at the LHC are model dependent, which implies that the searches provide limited constraints on scenarios such as supersymmetry (SUSY). The Simplified Models Spectra (SMS) framework used by ATLAS and CMS collaborations is useful to overcome this limitation. SMS framework involves a small number of parameters (all the properties are reduced to the mass spectrum, the production cross section and the branching ratio) and hence is more generic than presenting results in terms of soft parameters. In our work, the SMS framework was used to test Natural SUSY (NSUSY) scenario. To accomplish this task, two automated tools (SModelS and Fastlim) were used to decompose the NSUSY parameter space in terms of simplified models and confront the theoretical predictions against the experimental results. The achievement of both, just as the strengths and limitations, are here expressed for the NSUSY scenario.

  15. Implant success!!!.....simplified

    OpenAIRE

    Luthra Kaushal

    2009-01-01

    The endeavor towards life-like restoration has helped nurture new vistas in the art and science of implant dentistry. The protocol of “restoration-driven implant placement” ensures that the implant is an apical extension of the ideal future restoration and not the opposite. Meticulous pre-implant evaluation of soft and hard tissues, diagnostic cast and use of aesthetic wax-up and radiographic template combined with surgical template can simplify the intricate roadmap for appropriate implant t...

  16. Office 2010 Simplified

    CERN Document Server

    Shoup, Kate

    2010-01-01

    A clear, visual way to learn Office 2010 quickly and easily. If you're looking for a way to get up to speed quickly on the newest version of Microsoft Office, these 400 pages of step-by-step instructions and full-color screen shots make it easy. Office 2010 has new features and tools to master, and whether you're upgrading from an earlier version or encountering the Office applications for the first time, you'll appreciate this simplified approach. This easy-to-follow guide covers Word, Excel, PowerPoint, Outlook, and Publisher. Microsoft Office holds more than 90 percent of the market for Win

  17. Office 2013 simplified

    CERN Document Server

    Marmel, Elaine

    2013-01-01

    A basic introduction to learn Office 2013 quickly, easily, and in full color Office 2013 has new features and tools to master, and whether you're upgrading from an earlier version or using the Office applications for the first time, you'll appreciate this simplified approach. Offering a clear, visual style of learning, this book provides you with concise, step-by-step instructions and full-color screen shots that walk you through the applications in the Microsoft Office 2013 suite: Word, Excel, PowerPoint, Outlook, and Publisher.Shows you how to tackle dozens of Office 2013

  18. Windows 10 simplified

    CERN Document Server

    McFedries, Paul

    2015-01-01

    Learn Windows 10 quickly and painlessly with this beginner's guide Windows 10 Simplified is your absolute beginner's guide to the ins and outs of Windows. Fully updated to cover Windows 10, this highly visual guide covers all the new features in addition to the basics, giving you a one-stop resource for complete Windows 10 mastery. Every page features step-by-step screen shots and plain-English instructions that walk you through everything you need to know, no matter how new you are to Windows. You'll master the basics as you learn how to navigate the user interface, work with files, create

  19. Windows 8 simplified

    CERN Document Server

    McFedries, Paul

    2012-01-01

    The easiest way for visual learners to get started with Windows 8 The popular Simplified series makes visual learning easier than ever, and with more than 360,000 copies sold, previous Windows editions are among the bestselling Visual books. This guide goes straight to the point with easy-to-follow, two-page tutorials for each task. With full-color screen shots and step-by-step directions, it gets beginners up and running on the newest version of Windows right away. Learn to work with the new interface and improved Internet Explorer, manage files, share your computer, and much more. Perfect fo

  20. Simplified elastoplastic fatigue analysis

    International Nuclear Information System (INIS)

    Oligocyclic fatigue behaviour is a function of the local strain range. The design codes ASME section III, RCC-M, Code Case N47, RCC-MR, and the Guide issued by PNC propose simplified methods to evaluate the local strain range. After having briefly described these simplified methods, we tested them by comparing the results of experimental strains with those predicted by these rules. The experiments conducted for this study involved perforated plates under tensile stress, notched or reinforced beams under four-point bending stress, grooved specimens under tensile-compressive stress, and embedded grooved beams under bending stress. They display a relative conservatism depending on each case. The evaluation of the strains of rather inaccurate and sometimes lacks conservatism. So far, the proposal is to use the finite element codes with a simple model. The isotropic model with the cyclic consolidation curve offers a good representation of the real equivalent strain. There is obviously no question of representing the cycles and the entire loading history, but merely of calculating the maximum variation in elastoplastic equivalent deformations with a constant-rate loading. The results presented testify to the good prediction of the strains with this model. The maximum equivalent strain will be employed to evaluate fatigue damage

  1. Genetic Variation in the Catechol-O-Methyl Transferase Val108/158Met Is Linked to the Caudate and Posterior Cingulate Cortex Volume in Healthy Subjects: Voxel-Based Morphometry Analysis of Brain Magnetic Resonance Imaging.

    Directory of Open Access Journals (Sweden)

    Keita Watanabe

    Full Text Available The effect of the catechol-O-methyltransferase (COMT Val158Met polymorphism on brain morphology has been investigated but remains controversial. We hypothesized that a comparison between Val/Val and Val/Met individuals, which may represent the most different combinations concerning the effects of the COMT genotype, may reveal new findings. We investigated the brain morphology using 3-Tesla magnetic resonance imaging in 27 Val/Val and 22 Val/Met individuals. Voxel-based morphometry revealed that the volumes of the bilateral caudate and posterior cingulate cortex were significantly smaller in Val/Val individuals than in Val/Met individuals [right caudate: false discovery rate (FDR-corrected p = 0.048; left caudate: FDR-corrected p = 0.048; and bilateral posterior cingulate cortex: FDR-corrected p = 0.048]. This study demonstrates that interacting functional variants of COMT affect gray matter regional volumes in healthy subjects.

  2. The application of voxel-based morphometry in Alzheimer's disease%基于体素的形态测量学在阿尔茨海默病研究中的应用

    Institute of Scientific and Technical Information of China (English)

    郑东明; 王晓明

    2011-01-01

    @@ 基于体素的形态测量学(voxel-based morphometry,VBM)是一种基于像素水平对脑MR图像进行自动、全面、客观分析的技术,可以同时对整脑定量检测脑组织成分的密度,是评价脑灰、白质病变的一种新方法.该技术面世10年来,已经被广泛的应用到各种病理条件下脑结构变化的研究中,加深了人们对很多中枢神经系统疾病脑损伤的认识.

  3. Simplified fast neutron dosimeter

    Science.gov (United States)

    Sohrabi, Mehdi

    1979-01-01

    Direct fast-neutron-induced recoil and alpha particle tracks in polycarbonate films may be enlarged for direct visual observation and automated counting procedures employing electrochemical etching techniques. Electrochemical etching is, for example, carried out in a 28% KOH solution at room temperature by applying a 2000 V peak-to-peak voltage at 1 kHz frequency. Such recoil particle amplification can be used for the detection of wide neutron dose ranges from 1 mrad. to 1000 rads. or higher, if desired.

  4. 78 FR 66039 - Modification of National Customs Automation Program Test Concerning Automated Commercial...

    Science.gov (United States)

    2013-11-04

    ... concerning ACE Simplified Entry. See 76 FR 69755. The SE test established new entry capability to simplify... the SE test. See 77 FR 48527. In the notice published in the Federal Register on July 23, 2013 (78 FR... SECURITY U.S. Customs and Border Protection Modification of National Customs Automation Program...

  5. Pitfalls of voxel-based amyloid PET analyses for diagnosis of Alzheimer's disease. Artifacts due to non-specific uptake in the white matter and the skull

    International Nuclear Information System (INIS)

    Two methods are commonly used in brain image voxel-based analyses widely used for dementia work-ups: 3-dimensional stereotactic surface projections (3D-SSP) and statistical parametric mapping (SPM). The methods calculate the Z-scores of the cortical voxels that represent the significance of differences compared to a database of brain images with normal findings, and visualize them as surface brain maps. The methods are considered useful in amyloid positron emission tomography (PET) analyses to detect small amounts of amyloid-β deposits in early-stage Alzheimer's disease (AD), but are not fully validated. We analyzed the 11C-labeled 2-(2-[2-dimethylaminothiazol-5-yl]ethenyl)-6-(2-[fluoro]ethoxy)benzoxazole (BF-227) amyloid PET imaging of 56 subjects (20 individuals with mild cognitive impairment [MCl], 19 AD patients, and 17 non-demented [ND] volunteers) with 3D-SSP and the easy Z-score imaging system (eZIS) that is an SPM-based method. To clarify these methods' limitations, we visually compared Z-score maps output from the two methods and investigated the causes of discrepancies between them. Discrepancies were found in 27 subjects (9 MCl, 13 AD, and 5 ND). Relatively high white matter uptake was considered to cause higher Z-scores on 3D-SSP in 4 subjects (1 MCl and 3 ND). Meanwhile, in 17 subjects (6 MCl, 9 AD, and 2 ND), Z-score overestimation on eZIS corresponded with high skull uptake and disappeared after removing the skull uptake ('scalping'). Our results suggest that non-specific uptakes in the white matter and skull account for errors in voxel-based amyloid PET analyses. Thus, diagnoses based on 3D-SSP data require checking white matter uptake, and 'scalping' is recommended before eZIS analysis. (author)

  6. Simplified tritium permeation model

    International Nuclear Information System (INIS)

    In this model I seek to provide a simplified approach to solving permeation problems addressed by TMAP4. I will assume that there are m one-dimensional segments with thickness Li, i = 1, 2, hor-ellipsis, m, joined in series with an implantation flux, Ji, implanting at the single depth, δ, in the first segment. From material properties and heat transfer considerations, I calculate temperatures at each face of each segment, and from those temperatures I find local diffusivities and solubilities. I assume recombination coefficients Kr1 and Kr2 are known at the upstream and downstream faces, respectively, but the model will generate Baskes recombination coefficient values on demand. Here I first develop the steady-state concentration equations and then show how trapping considerations can lead to good estimates of permeation transient times

  7. Home Automation

    OpenAIRE

    Ahmed, Zeeshan

    2010-01-01

    In this paper I briefly discuss the importance of home automation system. Going in to the details I briefly present a real time designed and implemented software and hardware oriented house automation research project, capable of automating house's electricity and providing a security system to detect the presence of unexpected behavior.

  8. Voxel-based morphometry MRI study of gray matter change in patients with Parkinson's disease%帕金森病患者脑灰质变化的VBM-MRI研究

    Institute of Scientific and Technical Information of China (English)

    郭黎; 史长征; 胡艳; 彭子文; 杨柳; 徐安定

    2012-01-01

    Objective To delineate the gray matter changes of Parkinson's disease(PD) patients applied by voxel-based morphometry method (VBM) of magnetic resonance imaging (MRI). Methods of the regional gray matter volume was studied using voxel-based morphometry in 28 PD patients including 14 early stage PD (EPD) and 14 late stage PD (LPD) and 32 age- and education-matched controls. Results Compared with normal controls, PD patients had significant reductions of the gray matter volume in the frontal lobe (bilateral superior frontal gyrus, left inferior frontal gyrus), bilateral temporal lobes (superior temporal gyrus, middle temporal gyrus), right cingulated gyrus, right thalamus, bilateral caudate nucleus, and left inferior parietal lobe . Compared with EPD, LPD had significant reductions of gray matter volume in the frontal lobe(bilateral superior frontal gyrus, right inferior frontal gyrus, right orbitofrontal cortex and bilateral medial anterior frontal lobe), temporal lobe (right superior temporal gyrus, left middle temporal gyms),right parahippocampal gyrus, right caudate nucleus and right hypothalamus. Conclusions PD patients have significant reductions of the gray matter volume mainly in the frontal lobe, temporal lobe, right cingulate gyrus and subcor-tical gray matter. With the progression of PD, the reductions of gray matter volume increase in these regions and expend to the limbic system.%目的 应用核磁共振的基于体素形态学(voxel-based morphometry method of magnetic resonance imaging.VBM-MRI)技术,研究帕金森病(Parkinson disease,PD)患者大脑灰质变化的状况.方法 28例PD组与年龄、受教育年限相匹配32例健康对照组的VBM-MRI图像数据进行比较,PD组中,早期PD组(early Parkinson disease.EPD,n=14)与晚期PD组((late Parkinson disease.LPD,n=14)的VBM-MRI图像数据进行比较.结果 与健康对照组比较.VBM-MRI显示PD组患者存在下列脑区灰质体积减少:额叶(双侧额上回、左额下回)、双

  9. A simplified In Situ cosmogenic 14C extraction system

    Science.gov (United States)

    Pigati, J.S.; Lifton, N.A.; Timothy, Jull A.J.; Quade, Jay

    2010-01-01

    We describe the design, construction, and testing of a new, simplified in situ radiocarbon extraction system at the University of Arizona. Blank levels for the new system are low ((234 ?? 11) ?? 103 atoms (1 ??; n = 7)) and stable. The precision of a given measurement depends on the concentration of 14C, but is typically extraction system at Arizona, and lends itself to future automation. ?? 2010 by the Arizona Board of Regents on behalf of the University of Arizona.

  10. Comparison of 123I-MIBG myocardial scintigraphy, brain perfusion SPECT, and voxel-based MRI morphometry for distinguishing between dementia with Lewy bodies and Alzheimer's disease

    International Nuclear Information System (INIS)

    This study aimed to compare the diagnostic value of 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy, N-isopropyl-p[123I]iodoamphetamine (IMP) brain perfusion single-photon emission computed tomography (SPECT), and brain magnetic resonance imaging (MRI) voxel-based morphometry (VBM) for the differentiation of dementia with Lewy bodies (DLB) and Alzheimer's disease (AD). Thirty-five and 34 patients with probable DLB and probable AD, respectively, were enrolled. All patients underwent 123I-MIBG myocardial scintigraphy, 123I-IMP brain perfusion SPECT, and brain MRI. For 123I-MIBG imaging, we calculated early and delayed heart-to-mediastinum (H/M) uptake ratios. Three-dimensional stereotactic surface projections (3D-SSP) were used to analyze the results of 123I-IMP SPECT. VBM with statistical parametric mapping 8 plus diffeomorphic anatomical registration using exponentiated Lie algebra (DARTEL) was used to analyze the brain MRI data. The area under the receiver operating characteristic curves (AUC) for discriminating DLB and AD was highest (0.882) for the delayed H/M ratio on 123I-MIBG scintigraphy. AUC for z-score measurement in the occipital lobe was 0.818 and that for the extent of gray matter (GM) atrophy in the whole brain was 0.788. AUC for the combination of 3D-SSP and VBM analysis was 0.836. The respective sensitivities and specificities for distinguishing DLB from AD were 97.1 and 100% for the delayed H/M ratio using 123I-MIBG scintigraphy; 88.6 and 73.5% for the occipital lobe z-score using 3D-SSP analysis; 85.7 and 64.7% for the extent of whole brain GM atrophy using voxel-based MRI morphometry; and 91.4 and 76.5% for the combination of 3D-SSP analysis and VBM. 123I-MIBG myocardial scintigraphy was superior to brain perfusion SPECT and brain MRI using an advanced statistical technique to differentiate DLB and AD. (author)

  11. Analysis of the presence or absence of atrophy of the subgenual and subcallosal cingulate cortices using voxel-based morphometry on MRI is useful to select prescriptions for patients with depressive symptoms

    Directory of Open Access Journals (Sweden)

    Niida A

    2014-12-01

    Full Text Available Akira Niida,1 Richi Niida,2 Hiroshi Matsuda,3 Makoto Motomura,4 Akihiko Uechi5 1Department of Radiology, Nanbu Hospital, Itoman City, Okinawa, Japan; 2Department of Psychiatry, Nanto Clinic, Urasoe City, Okinawa, Japan; 3Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Kodaira City, Tokyo, Japan; 4Department of Human Sciences, University of the Ryukyus, Nakagami County, Okinawa, Japan; 5Cognitive Neuroscience Research Project, Kansai Gaidai University, Hirakata City, Osaka, Japan Objective: We objectively evaluated the presence or absence of atrophy of the subgenual anterior cingulate cortex (sgACC and the subcallosal anterior cingulate cortex (scACC, using new voxel-based morphometry (VBM software employing Statistical Parametric Mapping software v8 and diffeomorphic anatomic registration through an exponentiated lie algebra. We prepared a database covering young-mature adulthood and investigated the clinical usefulness of the evaluation. Subjects and methods: One hundred seven patients with major depressive disorder (MDD, 74 patients with bipolar disorder (BD, and 240 healthy control subjects underwent 1.5T magnetic resonance imaging scanning. Using new VBM software and databases covering young-mature adults and the elderly, target volumes of interest were set in the sgACC and scACC, four indicators (severity, extent, ratio, and whole-brain extent were determined, and the presence or absence of atrophy of the sgACC and scACC was evaluated on the basis of the indicators. In addition, the relationships between the presence or absence of atrophy of the sgACC and scACC and performance of diagnosing MDD and BD and therapeutic drugs were investigated. Results: It was clarified that the disease is likely to be MDD when atrophy is detected in the sgACC, and likely to be BD when no atrophy is detected in the sgACC but is detected in the scACC. Regarding the relationship with therapeutic drugs, it was clarified that, when

  12. Status of automated tensile machine

    International Nuclear Information System (INIS)

    The objective of this work is to develop the Monbusho Automated Tensile machine (MATRON) and install and operate it at the Pacific Northwest Laboratory (PNL). The machine is designed to provide rapid, automated testing of irradiated miniature tensile specimen in a vacuum at elevated temperatures. The MATRON was successfully developed and shipped to PNL for installation in a hot facility. The original installation plan was modified to simplify the current and subsequent installations, and the installation was completed. Detailed procedures governing the operation of the system were written. Testing on irradiated miniature tensile specimen should begin in the near future

  13. A METHOD OF VOXEL-BASED MORPHOMETRY AND ITS APPLICATIONS TO BRAIN IMAGE PROCESSING%基于像素的形态测量学方法及其在脑图像处理中的应用

    Institute of Scientific and Technical Information of China (English)

    郭小娟; 姚力; 金真

    2006-01-01

    基于像素的形态测量学(voxel-based morphometry,VBM)是一种基于像素对脑结构图像自动、全面、客观的分析技术,可定量检测脑组织成分的密度,从而进行不同群体间局部差异的比较.对VBM方法的提出、发展和应用做了简要的介绍,阐述了VBM的基本原理;并应用该方法对精神分裂症患者的脑结构磁共振图像进行了处理和分析,与正常人进行比较,发现了有意义的差异;并指出VBM方法的局限性以及利用该方法进行研究的意义.

  14. Research progress of voxel-based morphometry in obsessive-compulsive disorder%强迫症基于体素的形态测量学研究进展

    Institute of Scientific and Technical Information of China (English)

    陶甜美; 王国强

    2014-01-01

    T he neural imaging studies of obsessive-compulsive disorder (OCD ) indicate that OCD patients have abnormal brain structures and functions ,put forward the orbital frontal cortex-striatum "emotional"loop and the dorsolateral prefrontal cortex-striatum "executive"loop .In this paper ,we summarize voxel-based morphometry (VBM ) findings of two loop brain regions in recent years .%神经影像学的研究表明强迫症患者存在脑结构和功能异常,并提出了强迫症眶额叶-纹状体“情感”环路和背外侧前额叶-纹状体“执行”环路异常。本文对近年来这两个环路各个脑区基于体素的形态测量学研究结果进行了总结,为研究强迫症神经解剖结构的病理机制提供依据。

  15. The efficacy of a voxel-based morphometry on the analysis of imaging in schizophrenia, temporal lobe epilepsy, and Alzheimer's disease/mild cognitive impairment: a review

    Energy Technology Data Exchange (ETDEWEB)

    Kakeda, Shingo; Korogi, Yukunori [University of Occupational and Environmental Health School of Medicine, Department of Radiology, Kitakyushu (Japan)

    2010-08-15

    Voxel-based morphometry (VBM) done by means of MRI have provided new insights into the neuroanatomical basis for subjects with several conditions. Recently, VBM has been applied to investigate not only regional volumetric changes but also voxel-wise maps of fractional anisotropy (FA) computed from diffusion tensor imaging (DTI). The aim of this article is to review the recent work using VBM technique in particular focusing on schizophrenia, temporal lobe epilepsy (TLE), and Alzheimer's disease (AD)/mild cognitive impairment (MCI). In patients with schizophrenia, VBM approach detects the structural brain abnormalities that appear normal on conventional MRI. Moreover, this technique also has the potential to emerge as a useful clinical tool for early detection and monitoring of disease progression and treatment response in patients with schizophrenia or AD/MCI. In TLE, VBM approach may help elucidate some unresolved important research questions such as how recurrent temporal lobe seizures affect hippocampal and extrahippocampal morphology. Thus, in the future, large cohort studies to monitor whole brain changes on a VBM basis will lead to a further understanding of the neuropathology of several conditions. (orig.)

  16. Relationship between the catechol-O-methyl transferase Val108/158Met genotype and brain volume in treatment-naive major depressive disorder: Voxel-based morphometry analysis.

    Science.gov (United States)

    Watanabe, Keita; Kakeda, Shingo; Yoshimura, Reiji; Abe, Osamu; Ide, Satoru; Hayashi, Kenji; Katsuki, Asuka; Umene-Nakano, Wakako; Watanabe, Rieko; Nakamura, Jun; Korogi, Yukunori

    2015-09-30

    Catechol-O-methyltransferase (COMT) is a methylation enzyme engaged in the degradation of dopamine and noradrenaline by catalyzing the transfer of a methyl group from S-adenosylmethionine. An association was found between the Valine (Val) 108/158Methionine (Met) COMT polymorphism (rs4680) and major depressive disorder (MDD). The authors prospectively investigated the relationship between the Val108/158Met COMT genotype and voxel-based morphometry (VBM) findings for patients with first-episode and treatment-naïve MDD and healthy subjects (HS). Participants comprised 30 MDD patients and 48 age- and sex-matched HS who were divided according to the COMT genotype. Effects of diagnosis, COMT genotype, and the genotype-diagnosis interaction in relation to brain morphology in the Val/Met and Val/Val individuals were evaluated using a VBM analysis of high-resolution magnetic resonance imaging findings. Among the Val/Met individuals, the volume of the bilateral caudate was significantly smaller for MDD patients than for HS. In the Val/Val individuals, the caudate volume was comparable between MDD patients and HS. Significant genotype-diagnosis interaction effects on brain morphology were noted in the right caudate. PMID:26253436

  17. Simplified Universal Intelligent PID Controller

    OpenAIRE

    Mohamed I. Abu El- Sebah

    2016-01-01

    Many researches give a great attention to invent different techniques for process controller application. All of them tend to simplify the controller design algorithm and make it more intelligent, but the two goals seem to be an opposite goals. Although the artificial intelligent controller is proper, they need sometimes a complicated algorithm and parameter adaptation process. This paper presents a new idea to simplify the process controller, also to make it an intellige...

  18. Library Automation

    OpenAIRE

    Dhakne, B. N.; Giri, V. V; Waghmode, S. S.

    2010-01-01

    New technologies library provides several new materials, media and mode of storing and communicating the information. Library Automation reduces the drudgery of repeated manual efforts in library routine. By use of library automation collection, Storage, Administration, Processing, Preservation and communication etc.

  19. Process automation

    International Nuclear Information System (INIS)

    Process automation technology has been pursued in the chemical processing industries and to a very limited extent in nuclear fuel reprocessing. Its effective use has been restricted in the past by the lack of diverse and reliable process instrumentation and the unavailability of sophisticated software designed for process control. The Integrated Equipment Test (IET) facility was developed by the Consolidated Fuel Reprocessing Program (CFRP) in part to demonstrate new concepts for control of advanced nuclear fuel reprocessing plants. A demonstration of fuel reprocessing equipment automation using advanced instrumentation and a modern, microprocessor-based control system is nearing completion in the facility. This facility provides for the synergistic testing of all chemical process features of a prototypical fuel reprocessing plant that can be attained with unirradiated uranium-bearing feed materials. The unique equipment and mission of the IET facility make it an ideal test bed for automation studies. This effort will provide for the demonstration of the plant automation concept and for the development of techniques for similar applications in a full-scale plant. A set of preliminary recommendations for implementing process automation has been compiled. Some of these concepts are not generally recognized or accepted. The automation work now under way in the IET facility should be useful to others in helping avoid costly mistakes because of the underutilization or misapplication of process automation. 6 figs

  20. 基于体素的形态测量学在震颤麻痹型多系统萎缩中的应用%Voxel-based morphometry in the Parkinson variant of multiple system atrophy

    Institute of Scientific and Technical Information of China (English)

    赵彦萍; 王含; 李琢; 冯逢

    2010-01-01

    目的 评价震颤麻痹型多系统萎缩(MSA-P型)患者全脑灰、白质体积减少区域及分布特征.方法 选取13例临床拟诊为MSA-P型可能性大的患者及14名年龄匹配的正常对照者行全脑三维快速扰相梯度回波(3D fast spoiled gradient echo,3D-FSPGR)序列扫描,采用基于体素的形态测量学(voxel-based morphometry,VBM)分析方法的统计参数图软件(statistical parametric mapping,SPM)8,对MSA-P型患者及正常对照者的灰、白质体素进行分析.结果 与正常对照者相比,MSA-P患者的脑灰、白质体积均减少;脑灰质减少区多数区域呈双侧对称分布:包括双侧辅助运动区、背侧后扣带皮层、额叶内侧回、颞上回、小脑半球皮层等;少数区域仅累及单侧,如右侧初级运动皮层、体感联合皮层及左侧下前扣带皮层等.脑白质区主要累及双侧额上回、楔前叶、额叶下,左侧颞上回、扣带回及右侧额眶回、颞叶下等.结论 VBM方法具有自动、全面的特点,能客观地反映MSA-P患者组全脑结构的差异.%Objective To assess patterns of the gray and white matter atrophy in patients with multiple system atrophy-P(MSA-P)variant of whole brain compared with normal controls.Methods Three dimensional fast spoiled gradient echo(3D-FSPGR)T1WI of whole brain were obtained from 13 patients with probable MSA-P and 14 age-matched normal controls.The volume of gray matter(GM)and white matter (WM)of MSA-P patients and normal controls was analyzed with voxel-based morphometry(VBM) using statistical parametric mapping(SPM)8.Results Compared with the controls,the MSA-P patients showed decreased gray matter and white matter in bread areas. Gray matter loss mainly symmetrically distributed in bilateral supplementary motor area(SMA),dorsal posterior cingulate cortex(DPCC),medial frontal gyrus,superior temporal gyrus,cerebellum cortex,etc.Unilateral involvement of cortices mainly located in right primary motor cortex

  1. 海洛因依赖者脑灰质体积的VBM研究%Voxel Based Morphometry Study of Cerebral Gray Matter Volume in Patients With Heroin Dependence

    Institute of Scientific and Technical Information of China (English)

    朱佳; 王亚蓉; 李强; 李玮; 杨伟川; 吴宁; 常海峰; 王玮

    2012-01-01

    目的 探讨海洛因依赖对大脑灰质结构的作用,分析吸食海洛因总时间、吸食海洛因总量、每日吸食海洛因量等因素对脑灰质体积产生的影响.资料与方法 采用MRI对17例海洛因依赖者和15名健康受试者行3D 结构像扫描,所得数据用基于体素的形态学分析(voxel based morphometry,VBM)方法分析脑灰质体积,并比较两组之间的体积差异;分析脑灰质体积与吸食海洛因总时间、吸食海洛因总量、每日吸食海洛因量之间的相关关系.结果 与健康被试者相比,海洛因依赖者右侧眶额回、中央前回、左侧岛叶、扣带回、枕叶舌回灰质体积减少(P<0.005);控制年龄、受教育程度、每日吸烟量后,脑灰质体积变化与使用海洛因总时间、海洛因总量、每日吸食海洛因量之间无显著相关关系.结论 长期吸食海洛因导致脑灰质结构损害,主要涉及认知控制、情感、视觉控制等相关脑区.%Objective To investigate the effect of heroin on cerebral gray structure in patients with heroin dependence. Materials and Methods Seventeen heroin dependent patients and 15 normal volunteers performed 3D structural MR examination. The cerebral grey matter volume was measured by voxel based morphometry (VBM). The differences of cerebral grey matter volume between two groups were compared by two sample t-test. Partial correlation analysis was to measure the relativity between grey matter volume and the duration of heroin use, the total dose of heroin use as well as the everyday dose of heroin. Results Compared with the control group, the cerebral gray matter volume in heroin dependent group had a significant decrease (P <0. 005) in the right orbital frontal gyrus, right precentral gyrus, left insular, left cingulate gyrus and left lingual gyrus. Partial correlation analysis, which controlled for age, education and nicotine use factors, showed that the duration of heroin use, the total dose of

  2. Altered gray matter volume in primary trigeminal neuralgia:a voxel based morphometry MRI study%原发性三叉神经痛灰质体积变化的磁共振形态学研究

    Institute of Scientific and Technical Information of China (English)

    郭林英; 朱文珍; 田甜; 杨时骐; 覃媛媛; 汤翔宇; 王剑; 张巨

    2015-01-01

    Objective:To detect whether there is gray matter volume (GMV) alteration and further analyze the involvement of central nervous system in pain processing in trigeminal neuralgia patients. Materials and Methods:Nineteen patients diagnosed with trigeminal neuralgia and twenty-two age-matched, sex-matched normal volunteers as controls were recruited. T1-weighted 3D BRAVO sagittal images were obtained from all subjects. Voxel based morphometry(VBM) was used to identify GMV differences between patients and normal controls. The correlation between altered GMVs and disease duration as well as altered GMVs and pain intensity were also analyzed in trigeminal neuralgia patients. Results:Compared with normal controls, patients with trigeminal neuralgia had decreased GMV in left anterior cingulate as well as increased GMVs in right superior frontal gyrus, right insula, right putamen and bilateral cerebellum. Otherwise, we found a negative correlation between pain duration and altered GMV of the left anterior cingulate which is an important region for the development and maintenance of pain in trigeminal neuralgia. Conclusion:The altered GMV in central nervous system and the negative correlation between disease duration and altered GMV of the anterior cingulate may suggest that these central brain regions are extremely important for the development and maintenance of pain in trigeminal neuralgia, which reveals that exploring the central mechanisms of pain processing in trigeminal neuralgia may beneift new therapeutic methods in the future.%目的应用基于体素的形态学分析方法检测原发性三叉神经痛患者是否存在灰质体积改变,探索中枢神经系统在其疼痛处理中的作用。材料与方法对19例右侧三叉神经痛患者和22例年龄性别匹配的正常对照进行磁共振三维T1结构像扫描(3D-T1BRAVO),应用基于体素形态学分析(voxel-based morphometry,VBM)检测三叉神经痛患者全脑灰质体积的变化,探索

  3. Application of Voxel-Based Morphometry Technique in Patients with Mild Cognitive Impairment%基于体素的形态学测量技术在轻度认知障碍患者中的应用

    Institute of Scientific and Technical Information of China (English)

    卢万俊; 周红

    2008-01-01

    轻度认知障碍(MCI)指认知功能降低超出其年龄和受教育水平,但尚未影响到日常生活状态.超过半数的MCI患者会在5年内进展为痴呆.因此,MCI被认为是痴呆的危险状态,早期诊断MCI可以预防患者进展为痴呆.基于体素的形态学测量技术(VBM)能定量计算全脑和局部灰质体素的大小和信号强度,是一种完全自动化的客观脑形态分析技术.文章就VBM技术在MCI患者中的应用做了综述.%Mild cognitive impairment(MCI)refers to cognitive regression which goes beyond one'S age and education level,but does not influence the activities of daily living.More than half patients with MCI will develop dementia within five years.Therefore,MCI is considered as a risk status of dementia.Early diagnosis of MCI prevents against patients developing dementia. Voxel-based morphometry(VBM)technique quantitatively calculates the size of global and local gray matter voxel and signal intensity.It is a full automatic analysis technique of objective brain morphology.This article reviews the application of VBM technique in patient with MCI.

  4. Long operating cycle simplified BWR

    International Nuclear Information System (INIS)

    Considering next generation requirement for nuclear plants, a long cycle operating simplified BWR (LSBWR) concept is proposed. The major features of LSBWR are; 1) Long cycle operation core using uranium fuels; 2) Simplified system and component as well as passive systems; 3) Combined building concept with ship hull structure. This concept have potential to reduce construction cost and to Increase availability. Safety feature of LSBWR makes possible to attain no evacuation capability in case of a severe accident. Further research and development is underway. (author)

  5. Simplified design of filter circuits

    CERN Document Server

    Lenk, John

    1999-01-01

    Simplified Design of Filter Circuits, the eighth book in this popular series, is a step-by-step guide to designing filters using off-the-shelf ICs. The book starts with the basic operating principles of filters and common applications, then moves on to describe how to design circuits by using and modifying chips available on the market today. Lenk's emphasis is on practical, simplified approaches to solving design problems.Contains practical designs using off-the-shelf ICsStraightforward, no-nonsense approachHighly illustrated with manufacturer's data sheets

  6. Simplified High-Power Inverter

    Science.gov (United States)

    Edwards, D. B.; Rippel, W. E.

    1984-01-01

    Solid-state inverter simplified by use of single gate-turnoff device (GTO) to commutate multiple silicon controlled rectifiers (SCR's). By eliminating conventional commutation circuitry, GTO reduces cost, size and weight. GTO commutation applicable to inverters of greater than 1-kilowatt capacity. Applications include emergency power, load leveling, drives for traction and stationary polyphase motors, and photovoltaic-power conditioning.

  7. SEA - A Simplified Employee Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Busby, L

    2001-04-23

    This paper presents a proposal for modifying the current employee annual evaluation process in SCAD. It purports to simplify that process, primarily by breaking up the resultant document into a set of more or less independent components. It claims to reduce the overall time and effort required from each actor.

  8. Simplifying the Water Poverty Index

    Science.gov (United States)

    Cho, Danny I.; Ogwang, Tomson; Opio, Christopher

    2010-01-01

    In this paper, principal components methodology is used to derive simplified and cost effective indexes of water poverty. Using a well known data set for 147 countries from which an earlier five-component water poverty index comprising of "Resources," "Access," "Capacity," "Use" and "Environment" was constructed, we find that a simplified…

  9. Simplifying plasma chemistry via ILDM

    Science.gov (United States)

    Rehman, T.; Kemaneci, E.; Graef, W.; van Dijk, J.

    2016-02-01

    A plasma fluid model containing a large number of chemical species and reactions yields a high computational load. One of the methods to overcome this difficulty is to apply Chemical Reduction Techniques as used in combustion engineering. The chemical reduction technique that we study here is ILDM (Intrinsic Lower Dimensional Manifold). The ILDM method is used to simplify an argon plasma model and then a comparison is made with a CRM (Collisional Radiative Model).

  10. Simplifying Tensor Polynomials with Indices

    CERN Document Server

    Balfagón, A

    1998-01-01

    We are presenting an algorithm capable of simplifying tensor polynomials with indices when the building tensors have index symmetry properties. These properties include simple symmetry, cyclicity and those due to the presence of partial and covariant derivatives. We are also including some examples using the Riemann tensor as a paradigm. The algorithm is part of a Mathematica package called Tools of Tensor Calculus (TTC) [web address: http//baldufa.upc.es/ttc

  11. Simplified Universal Intelligent PID Controller

    Directory of Open Access Journals (Sweden)

    Mohamed I. Abu El- Sebah

    2016-01-01

    Full Text Available Many researches give a great attention to invent different techniques for process controller application. All of them tend to simplify the controller design algorithm and make it more intelligent, but the two goals seem to be an opposite goals. Although the artificial intelligent controller is proper, they need sometimes a complicated algorithm and parameter adaptation process. This paper presents a new idea to simplify the process controller, also to make it an intelligent controller. Moreover, the proposed controller is used as universal controller. The paper also contains details of the controller design and development. This Simplified Universal Intelligent PID (SUI-PID controller is designed to yield a good command tracking for different systems. The proposed controller can be designed using a very simple logic algorithm. This algorithm adapts the controller parameters automatically, therefore no need for controller adaptation. The proposed controller is simulated using Matlab Simulation software package and applied to different systems to verify the controller properties effectiveness. The simulation results illustrate an excellent performance of the proposed controller, which used as a universal controller for any system.

  12. Morphometric changes of whole brain in patients with alcohol addiction: a voxel-based morphometry study%酒精成瘾者的体素全脑形态测量学分析

    Institute of Scientific and Technical Information of China (English)

    李金锋; 陈志晔; 马林

    2011-01-01

    目的:应用基于体素的形态测量学( VBM)方法分析酒精成瘾患者脑结构的变化。方法 采用3.0T超导MR系统,对15例酒精成瘾者(患者组)和15例年龄和性别与之相匹配的正常成年志愿者(对照组)行MR脑结构像扫描,并应用VBM方法对图像进行分析,全脑体积的比较采用成组t检验。结果 酒精成瘾者局部灰质体积明显萎缩脑区为左侧额中回、额上回、楔前回、直回及右侧额上回内侧、眶回。白质萎缩的区域为双侧额上回白质。全脑体积分析显示患者组脑白质体积[ (675.14±70.62) ml]及脑实质体积[(1578.8l±199.05) ml]较对照组脑白质体积[(841.33±177.35) ml]及脑实质体积[(1722.13±117.62) ml]明显减小(t值分别为11.37、5.764,P值均<0.05),患者组全脑灰质体积[(903.67±139.87) ml]较对照组[(880.79±157.10) ml]未见减小(t =0.177,P>0.05)。结论 酒精成瘾者脑部早期变化可表现为局部脑灰质、白质结构的萎缩,额叶灰质及白质是酒精性脑损伤相对特异的脑区。VBM对于评估酒精性成瘾者脑萎缩有一定的价值。%Objective To evaluate morphometric changes of brain in patients with alcohol addiction by voxel-based morphometry. Methods Fifteen patients with alcohol addiction and 15 health controls were recruited and underwent fluid attenuated inversion recovery (FLAIR) and 3D fast spoiled gradient echo (FSPGR) T1 -weighted sequences on a 3.0 T MRI system. 3D FSPGR T1 structure images were normalized,segmented and smoothed, and then underwent voxel-based morphometry. An ANCOVA was applied with age,body mass index ( BMI ), and education years as covariates because of exact sex match. A statistical threshold of P < 0. 01 (uncorrected) and more than continuous 50 voxels were determined as significant.Results Regional results showed there was a significant reduction of gray matter volume in left middle frontal gyrus, superior frontal gyrus

  13. 78 FR 53466 - Modification of Two National Customs Automation Program (NCAP) Tests Concerning Automated...

    Science.gov (United States)

    2013-08-29

    ... capability, known as the Simplified Entry (SE) test. 78 FR 44142. That document contained an error in Section... the DIS. Correction In the Federal Register of July 23, 2013, in the document at 78 FR 44142, on page... SECURITY U.S. Customs and Border Protection Modification of Two National Customs Automation Program...

  14. Simplified design of IC amplifiers

    CERN Document Server

    Lenk, John

    1996-01-01

    Simplified Design of IC Amplifiers has something for everyone involved in electronics. No matter what skill level, this book shows how to design and experiment with IC amplifiers. For experimenters, students, and serious hobbyists, this book provides sufficient information to design and build IC amplifier circuits from 'scratch'. For working engineers who design amplifier circuits or select IC amplifiers, the book provides a variety of circuit configurations to make designing easier.Provides basics for all phases of practical design.Covers the most popular forms for amplif

  15. Windows 8.1 simplified

    CERN Document Server

    McFedries, Paul

    2013-01-01

    The easiest way for visual learners to get started with Windows 8 The popular Simplified series makes visual learning easier than ever, and with more than 400,000 copies sold, previous Windows editions are among the bestselling Visual books. Using a Visual approach, this book covers the new features of Windows 8.1 and provides step-by-step instructions for readers who are entirely new to the subject. Inside, you'll discover tasks on topics such as: Windows basics, creating movies, sharing their computer, working with and managing files, browsing the web, and new ways to customize Windows to w

  16. A simplified indirect bonding technique

    Directory of Open Access Journals (Sweden)

    Radha Katiyar

    2014-01-01

    Full Text Available With the advent of lingual orthodontics, indirect bonding technique has become an integral part of practice. It involves placement of brackets initially on the models and then their transfer to teeth with the help of transfer trays. Problems encountered with current indirect bonding techniques used are (1 the possibility of adhesive flash remaining around the base of the brackets which requires removal (2 longer time required for the adhesive to gain enough bond strength for secure tray removal. The new simplified indirect bonding technique presented here overcomes both these problems.

  17. Automation Security

    OpenAIRE

    Mirzoev, Dr. Timur

    2014-01-01

    Web-based Automated Process Control systems are a new type of applications that use the Internet to control industrial processes with the access to the real-time data. Supervisory control and data acquisition (SCADA) networks contain computers and applications that perform key functions in providing essential services and commodities (e.g., electricity, natural gas, gasoline, water, waste treatment, transportation) to all Americans. As such, they are part of the nation s critical infrastructu...

  18. A GOMS model applied to a simplified control panel design

    International Nuclear Information System (INIS)

    The design of the user interface for a new system requires many decisions to be considered. To develop sensitivity to user needs requires understanding user behavior. The how-to-do-it knowledge is a mixture of task-related and interface-related components. A conscientious analysis of these components, allows the designer to construct a model in terms of goals, operators, methods, and selection (GOMS model) rules that can be advantageously used in the design process and evaluation of a user interface. The emphasis of the present work is on describing the importance and use of a GOMS model as a formal user interface analysis tool in the development of a simplified panel for the control of a nuclear power plant. At Pennsylvania State University, a highly automated control system with a greatly simplified human interface has been proposed to improve power plant safety. Supervisory control is to be conducted with a simplified control panel with the following functions: startup, shutdown, increase power, decrease power, reset, and scram. Initial programming of the operator interface has been initiated within the framework of a U.S. Department of Energy funded university project for intelligent distributed control. A hypothesis to be tested is that this scheme can be also used to estimate mental work load content and predict human performance

  19. Simplified model for DNB analysis

    International Nuclear Information System (INIS)

    In a pressurized water nuclear reactor (PWR), the power of operation is restricted by the possibility of the occurrence of the departure from nucleate boiling called DNB (Departure from Nucleate Boiling) in the hottest channel of the core. The present work proposes a simplified model that analyses the thermal-hydraulic conditions of the coolant in the hottest channel of PWRs with the objective to evaluate BNB in this channel. For this the coupling between the hot channel and typical nominal channels assumed imposing the existence of a cross flow between these channels in a way that a uniforme pressure axial distribution results along the channels. The model is applied for Angra-I reactor and the results are compared with those of Final Safety Analysis Report (FSAR) obtained by Westinghouse through the THINC program, beeing considered satisfactory (Author)

  20. 2D SIMPLIFIED SERVO VALVE

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A novel pilot stage valve called simplified 2D valve, which utilizes both rotary and linear motions of a single spool, is presented.The rotary motion of the spool incorporating hydraulic resistance bridge, formed by a damper groove and a crescent overlap opening, is utilized as pilot to actuate linear motion of the spool.A criterion for stability is derived from the linear analysis of the valve.Special experiments are designed to acquire the mechanical stiffness, the pilot leakage and the step response.It is shown that the sectional size of the spiral groove affects the dynamic response and the stiffness contradictorily and is also very sensitive to the pilot leakage.Therefore, it is necessary to establish a balance between the static and dynamic characteristics in deciding the structural parameters.Nevertheless, it is possible to sustain the dynamic response at a fairly high level, while keeping the leakage of the pilot stage at an acceptable level.

  1. Simplified SIMPs and the LHC

    Science.gov (United States)

    Daci, N.; De Bruyn, I.; Lowette, S.; Tytgat, M. H. G.; Zaldivar, B.

    2015-11-01

    The existence of Dark Matter (DM) in the form of Strongly Interacting Massive Particles (SIMPs) may be motivated by astrophysical observations that challenge the classical Cold DM scenario. Other observations greatly constrain, but do not completely exclude, the SIMP alternative. The signature of SIMPs at the LHC may consist of neutral, hadron-like, trackless jets produced in pairs. We show that the absence of charged content can provide a very efficient tool to suppress dijet backgrounds at the LHC, thus enhancing the sensitivity to a potential SIMP signal. We illustrate this using a simplified SIMP model and present a detailed feasibility study based on simulations, including a dedicated detector response parametrization. We evaluate the expected sensitivity to various signal scenarios and tentatively consider the exclusion limits on the SIMP elastic cross section with nucleons.

  2. Simplified SIMPs and the LHC

    CERN Document Server

    Daci, Nadir; Lowette, Steven; Tytgat, Michel H G; Zaldivar, Bryan

    2015-01-01

    The existence of Dark Matter (DM) in the form of Strongly Interacting Massive Particles (SIMPs) may be motivated by astrophysical observations that challenge the classical Cold DM scenario. Other observations greatly constrain, but do not completely exclude, the SIMP alternative. The signature of SIMPs at the LHC may consist of neutral, hadron-like, trackless jets produced in pairs. We show that the absence of charged content can provide a very efficient tool to suppress dijet backgrounds at the LHC, thus enhancing the sensitivity to a potential SIMP signal. We illustrate this using a simplified SIMP model and present a detailed feasibility study based on simulations, including a dedicated detector response parametrization. We evaluate the expected sensitivity to various signal scenarios and tentatively consider the exclusion limits on the SIMP elastic cross section with nucleons.

  3. A voxel-based morphometric study on change of gray matter structures in cerebral palsy%基于体素形态测量学检测脑性瘫痪患儿脑灰质结构改变

    Institute of Scientific and Technical Information of China (English)

    王莹; 王海宝; 余永强; 徐丽艳; 陈玉萍; 吴德

    2015-01-01

    Objective To measure gray matter volume of whole brain with voxel-based morphometry (VBM) method and to study brain structures associated with gross motor function.Method Forty children with cerebral palsy were recruited in the authors' hospital from Oct.2012 to Dec.2013 (26 male,14 female cases,average age (3.6 ± 2.0) years).Gross motor function classification system (GMFCS) for children was used to obtain their motor function.The whole-brain three dimensional magnetic resonance imaging (MRI) was performed on a 3.0 T MRI scanner.The data were segmented by VBM 5,and the whole brain volumes of gray matter,white matter and cerebospinal fluid were produced.Correlation analysis was used to analyze the correlation of GMFCS with whole brain volumes using SPM 5 in Matalab 7.1.Result The volume in left meditemporal gyrus (Z =3.57) and inferior temporal gyrus (Z =3.40),right thalamus and pallidum (Z =3.36),left thalamus and pallidum (Z =2.76),left supramarginal gyrus (Z =3.14),left precuneus gyrus (Z =3.00),right dorsolateral superior frontal gyrus (Z =3.08),right superior and medial occipital gyrus (Z =2.84) significantly increased as aggravation of gross motor dysfunction.The volume of the left medial orbitofrontal lobe and anterior cingulate (Z =3.28,3.02),left medial superior frontal gyrus (Z =3.19),left caudate (Z =3.04,2.94,2.92),left cerebellum (Z =2.94),right cerebellum (Z =2.97),left parahippocampal (Z =3.94),right parahippocampal (Z =3.43,3.00),left insula (Z =3.50),right insula (Z =3.41,3.80),left lingual (Z =3.37),right lingual (Z =3.30),left post cingulum (Z =2.73),left midioccipital gyrus (Z =2.92) and right miditemporal gyrus (Z =3.05) significantly reduced as the aggravation of gross motor dysfunction (P all < 0.005).Conclusion GMFCS in children with cerebral palsy is related to abnormalities of brain gray matter structure for motor,emotion,memory and default model network when examined with VBM method.%目的 应用基于体素形态测量学(VBM)技术

  4. Software Test Automation in Practice: Empirical Study from Sri Lanka

    OpenAIRE

    S.Hushalini; R.P.A.A. Randunu; R.M.Maddumahewa; C. D. Manawadu

    2014-01-01

    In today, software projects are more complex than ever before, bugs are found before the product released and always creep in and often reappear. The Objective of the automated testing is to simplify as much of the testing effort as possible with minimum scripts. Automated software testing is the best way to increase the effectiveness, efficiency and coverage of software testing for software projects and also enables an organization to influence technology to perform tedious repetitive tasks ...

  5. Automated Budget System

    Data.gov (United States)

    Department of Transportation — The Automated Budget System (ABS) automates management and planning of the Mike Monroney Aeronautical Center (MMAC) budget by providing enhanced capability to plan,...

  6. Simplified SUSY at the ILC

    CERN Document Server

    Berggren, Mikael

    2013-01-01

    At the ILC, one has the possibility to search for SUSY in an model-independent way: The corner-stone of SUSY is that sparticles couple as particles. This is independent of the mechanism responsible for SUSY breaking. Any model will have one Lightest SUSY Particle (LSP), and one Next to Lightest SUSY Particle (NLSP). In models with conserved R-parity, the NLSP must decay solely to the LSP and the SM partner of the NLSP. Therefore, studying NLSP production and decay can be regarded as a "simplified model without simplification": Any SUSY model will have such a process. The NLSP could be any sparticle: a slepton, an electroweak-ino, or even a squark. However, since there are only a finite number of sparticles, one can systematically search for signals of all possible NLSP:s. This way, the entire space of models that have a kinematicall y reachable NLSP can be covered. For any NLSP, the "worst case" can be determined, since the SUSY principle allows to calculate the cross-section once the NLSP nature and mass are...

  7. Conceptual design of simplified PWR

    International Nuclear Information System (INIS)

    The authors believe the next generation nuclear power plant should be characterized by: (1) simplicity of design; (2) ease of operation and maintenance; (3) economic conformance with safety requirements; and (4) technologies easy to understand by the public. In a joint effort to develop a new generation nuclear power plant which is more friendly to operator and maintenance personnel and is economically competitive with alternative sources of power generation, the Japan Atomic Power Company (JAPC) supported by the other Japanese PWR Utilities, Electricite de France (EdF), Westinghouse (WH) and Mitsubishi Heavy Industry (MHI) have studied application of passive technologies at a power rating of about 1,000 MWe. The limited availability for location of nuclear power plant in Japan makes plants with higher power ratings more desirable. Using the AP-600 reference design as a basis, the authors enlarged the plant size to 3 -loops and added engineering features to conform with Japanese practice and Utilities' preference. The Simplified PWR (SPWR) program definitively confirmed the feasibility of a passive plant with an NSSS rating about 1,000 MWe and 3 loops

  8. Genetic circuit design automation.

    Science.gov (United States)

    Nielsen, Alec A K; Der, Bryan S; Shin, Jonghyeon; Vaidyanathan, Prashant; Paralanov, Vanya; Strychalski, Elizabeth A; Ross, David; Densmore, Douglas; Voigt, Christopher A

    2016-04-01

    Computation can be performed in living cells by DNA-encoded circuits that process sensory information and control biological functions. Their construction is time-intensive, requiring manual part assembly and balancing of regulator expression. We describe a design environment, Cello, in which a user writes Verilog code that is automatically transformed into a DNA sequence. Algorithms build a circuit diagram, assign and connect gates, and simulate performance. Reliable circuit design requires the insulation of gates from genetic context, so that they function identically when used in different circuits. We used Cello to design 60 circuits forEscherichia coli(880,000 base pairs of DNA), for which each DNA sequence was built as predicted by the software with no additional tuning. Of these, 45 circuits performed correctly in every output state (up to 10 regulators and 55 parts), and across all circuits 92% of the output states functioned as predicted. Design automation simplifies the incorporation of genetic circuits into biotechnology projects that require decision-making, control, sensing, or spatial organization. PMID:27034378

  9. Simplified computer codes for cask impact analysis

    International Nuclear Information System (INIS)

    In regard to the evaluation of the acceleration and deformation of casks, the simplified computer codes make analyses economical and decrease input and calculation time. The results obtained by the simplified computer codes have enough adequacy for their practical use. (J.P.N.)

  10. Simplified SUSY at the ILC

    Energy Technology Data Exchange (ETDEWEB)

    Berggren, Mikael

    2013-08-15

    At the ILC, one has the possibility to search for SUSY in an model-independent way: The corner-stone of SUSY is that sparticles couple as particles. This is independent of the mechanism responsible for SUSY breaking. Any model will have one Lightest SUSY Particle (LSP), and one Next to Lightest SUSY Particle (NLSP). In models with conserved R-parity, the NLSP must decay solely to the LSP and the SM partner of the NLSP. Therefore, studying NLSP production and decay can be regarded as a ''simplified model without simplification'': Any SUSY model will have such a process. The NLSP could be any sparticle: a slepton, an electroweak-ino, or even a squark. However, since there are only a finite number of sparticles, one can systematically search for signals of all possible NLSP:s. This way, the entire space of models that have a kinematically reachable NLSP can be covered. For any NLSP, the ''worst case'' can be determined, since the SUSY principle allows to calculate the cross-section once the NLSP nature and mass are given. The region in the LSP-NLSP mass-plane where the ''worst case'' could be discovered or excluded experimentally can be found by estimating background and efficiency at each point in the plane. From experience at LEP, it is expected that the lower signal-to background ratio will indeed be found for models with conserved R-parity. In this document, we show that at the ILC, such a program is possible, as it was at LEP. No loop-holes are left, even for difficult or non-standard cases: whatever the NLSP is it will be detectable.

  11. Simplified SUSY at the ILC

    International Nuclear Information System (INIS)

    At the ILC, one has the possibility to search for SUSY in an model-independent way: The corner-stone of SUSY is that sparticles couple as particles. This is independent of the mechanism responsible for SUSY breaking. Any model will have one Lightest SUSY Particle (LSP), and one Next to Lightest SUSY Particle (NLSP). In models with conserved R-parity, the NLSP must decay solely to the LSP and the SM partner of the NLSP. Therefore, studying NLSP production and decay can be regarded as a ''simplified model without simplification'': Any SUSY model will have such a process. The NLSP could be any sparticle: a slepton, an electroweak-ino, or even a squark. However, since there are only a finite number of sparticles, one can systematically search for signals of all possible NLSP:s. This way, the entire space of models that have a kinematically reachable NLSP can be covered. For any NLSP, the ''worst case'' can be determined, since the SUSY principle allows to calculate the cross-section once the NLSP nature and mass are given. The region in the LSP-NLSP mass-plane where the ''worst case'' could be discovered or excluded experimentally can be found by estimating background and efficiency at each point in the plane. From experience at LEP, it is expected that the lower signal-to background ratio will indeed be found for models with conserved R-parity. In this document, we show that at the ILC, such a program is possible, as it was at LEP. No loop-holes are left, even for difficult or non-standard cases: whatever the NLSP is it will be detectable.

  12. Simplified Models for LHC New Physics Searches

    CERN Document Server

    Alves, Daniele; Arora, Sanjay; Bai, Yang; Baumgart, Matthew; Berger, Joshua; Buckley, Matthew; Butler, Bart; Chang, Spencer; Cheng, Hsin-Chia; Cheung, Clifford; Chivukula, R.Sekhar; Cho, Won Sang; Cotta, Randy; D'Alfonso, Mariarosaria; El Hedri, Sonia; Essig, Rouven; Evans, Jared A.; Fitzpatrick, Liam; Fox, Patrick; Franceschini, Roberto; Freitas, Ayres; Gainer, James S.; Gershtein, Yuri; Gray, Richard; Gregoire, Thomas; Gripaios, Ben; Gunion, Jack; Han, Tao; Haas, Andy; Hansson, Per; Hewett, JoAnne; Hits, Dmitry; Hubisz, Jay; Izaguirre, Eder; Kaplan, Jared; Katz, Emanuel; Kilic, Can; Kim, Hyung-Do; Kitano, Ryuichiro; Koay, Sue Ann; Ko, Pyungwon; Krohn, David; Kuflik, Eric; Lewis, Ian; Lisanti, Mariangela; Liu, Tao; Liu, Zhen; Lu, Ran; Luty, Markus; Meade, Patrick; Morrissey, David; Mrenna, Stephen; Nojiri, Mihoko; Okui, Takemichi; Padhi, Sanjay; Papucci, Michele; Park, Michael; Park, Myeonghun; Perelstein, Maxim; Peskin, Michael; Phalen, Daniel; Rehermann, Keith; Rentala, Vikram; Roy, Tuhin; Ruderman, Joshua T.; Sanz, Veronica; Schmaltz, Martin; Schnetzer, Stephen; Schuster, Philip; Schwaller, Pedro; Schwartz, Matthew D.; Schwartzman, Ariel; Shao, Jing; Shelton, Jessie; Shih, David; Shu, Jing; Silverstein, Daniel; Simmons, Elizabeth; Somalwar, Sunil; Spannowsky, Michael; Spethmann, Christian; Strassler, Matthew; Su, Shufang; Tait, Tim; Thomas, Brooks; Thomas, Scott; Toro, Natalia; Volansky, Tomer; Wacker, Jay; Waltenberger, Wolfgang; Yavin, Itay; Yu, Felix; Zhao, Yue; Zurek, Kathryn

    2012-01-01

    This document proposes a collection of simplified models relevant to the design of new-physics searches at the LHC and the characterization of their results. Both ATLAS and CMS have already presented some results in terms of simplified models, and we encourage them to continue and expand this effort, which supplements both signature-based results and benchmark model interpretations. A simplified model is defined by an effective Lagrangian describing the interactions of a small number of new particles. Simplified models can equally well be described by a small number of masses and cross-sections. These parameters are directly related to collider physics observables, making simplified models a particularly effective framework for evaluating searches and a useful starting point for characterizing positive signals of new physics. This document serves as an official summary of the results from the "Topologies for Early LHC Searches" workshop, held at SLAC in September of 2010, the purpose of which was to develop a...

  13. Simplified Application of Material Efficiency Green Metrics to Synthesis Plans: Pedagogical Case Studies Selected from "Organic Syntheses"

    Science.gov (United States)

    Andraos, John

    2015-01-01

    This paper presents a simplified approach for the application of material efficiency metrics to linear and convergent synthesis plans encountered in organic synthesis courses. Computations are facilitated and automated using intuitively designed Microsoft Excel spreadsheets without invoking abstract mathematical formulas. The merits of this…

  14. Automated classification of norms in sources of law

    NARCIS (Netherlands)

    E. de Maat; R. Winkels

    2008-01-01

    The research described here attempts to achieve automated support for modelling sources of law for legal knowledge based systems and services. Many existing systems use models that do not reflect the entire law, and simplify parts of the text. These models are difficult to validate, maintain and re-

  15. Manufacturing and automation

    OpenAIRE

    Ernesto Córdoba Nieto

    2010-01-01

    The article presents concepts and definitions from different sources concerning automation. The work approaches automation by virtue of the author’s experience in manufacturing production; why and how automation prolects are embarked upon is considered. Technological reflection regarding the progressive advances or stages of automation in the production area is stressed. Coriat and Freyssenet’s thoughts about and approaches to the problem of automation and its current state are taken and e...

  16. Development and application of an automated analysis method for individual cerebral perfusion single photon emission tomography images

    CERN Document Server

    Cluckie, A J

    2001-01-01

    Neurological images may be analysed by performing voxel by voxel comparisons with a group of control subject images. An automated, 3D, voxel-based method has been developed for the analysis of individual single photon emission tomography (SPET) scans. Clusters of voxels are identified that represent regions of abnormal radiopharmaceutical uptake. Morphological operators are applied to reduce noise in the clusters, then quantitative estimates of the size and degree of the radiopharmaceutical uptake abnormalities are derived. Statistical inference has been performed using a Monte Carlo method that has not previously been applied to SPET scans, or for the analysis of individual images. This has been validated for group comparisons of SPET scans and for the analysis of an individual image using comparison with a group. Accurate statistical inference was obtained independent of experimental factors such as degrees of freedom, image smoothing and voxel significance level threshold. The analysis method has been eval...

  17. Use of automated image registration to generate mean brain SPECT image of Alzheimer's patients

    International Nuclear Information System (INIS)

    The purpose of this study was to compute and compare the group mean HMPAO brain SPECT images of patients with senile dementia of Alzheimer's type (SDAT) and age matched control subjects after transformation of the individual images to a standard size and shape. Ten patients with Alzheimer's disease (age 71.6±5.0 yr) and ten age matched normal subjects (age 71.0±6.1 yr) participated in this study. Tc-99m HMPAO brain SPECT and X-ray CT scans were acquired for each subject. SPECT images were normalized to an average activity of 100 counts/pixel. Individual brain images were transformed to a standard size and shape with the help of Automated Image Registration (AIR). Realigned brain SPECT images of both groups were used to generate mean and standard deviation images by arithmetic operations on voxel based numerical values. Mean images of both groups were compared by applying the unpaired t-test on a voxel by voxel basis to generate three dimensional T-maps. X-ray CT images of individual subjects were evaluated by means of a computer program for brain atrophy. A significant decrease in relative radioisotope (RI) uptake was present in the bilateral superior and inferior parietal lobules (p<0.05), bilateral inferior temporal gyri, and the bilateral superior and middle frontal gyri (p<0.001). The mean brain atrophy indices for patients and normal subjects were 0.853±0.042 and 0.933±0.017 respectively, the difference being statistically significant (p<0.001). The use of a brain image standardization procedure increases the accuracy of voxel based group comparisons. Thus, intersubject averaging enhances the capacity for detection of abnormalities in functional brain images by minimizing the influence of individual variation. (author)

  18. 3.6 simplified methods for design

    International Nuclear Information System (INIS)

    Simplified design analysis methods for elevated temperature construction are classified and reviewed. Because the major impetus for developing elevated temperature design methodology during the past ten years has been the LMFBR program, considerable emphasis is placed upon results from this source. The operating characteristics of the LMFBR are such that cycles of severe transient thermal stresses can be interspersed with normal elevated temperature operational periods of significant duration, leading to a combination of plastic and creep deformation. The various simplified methods are organized into two general categories, depending upon whether it is the material, or constitutive, model that is reduced, or the geometric modeling that is simplified. Because the elastic representation of material behavior is so prevalent, an entire section is devoted to elastic analysis methods. Finally, the validation of the simplified procedures is discussed

  19. Interactive Simplifier Tracing and Debugging in Isabelle

    OpenAIRE

    Hupel, Lars

    2014-01-01

    The Isabelle proof assistant comes equipped with a very powerful tactic for term simplification. While tremendously useful, the results of simplifying a term do not always match the user's expectation: sometimes, the resulting term is not in the form the user expected, or the simplifier fails to apply a rule. We describe a new, interactive tracing facility which offers insight into the hierarchical structure of the simplification with user-defined filtering, memoization and search. The new si...

  20. Monojet Searches for MSSM Simplified Models

    CERN Document Server

    Arbey, A; Mahmoudi, F

    2015-01-01

    We explore the implications of monojet searches at hadron colliders in the MSSM. To quantify the impact of monojet searches, we consider simplified MSSM scenarios with neutralino dark matter. The monojet results of the LHC Run 1 are reinterpreted in the context of several MSSM simplified scenarios, and the complementarity with direct SUSY search results is highlighted. We also investigate the reach of monojet searches for the Run 2, as well as for future higher energy hadron colliders.

  1. Manufacturing and automation

    Directory of Open Access Journals (Sweden)

    Ernesto Córdoba Nieto

    2010-04-01

    Full Text Available The article presents concepts and definitions from different sources concerning automation. The work approaches automation by virtue of the author’s experience in manufacturing production; why and how automation prolects are embarked upon is considered. Technological reflection regarding the progressive advances or stages of automation in the production area is stressed. Coriat and Freyssenet’s thoughts about and approaches to the problem of automation and its current state are taken and examined, especially that referring to the problem’s relationship with reconciling the level of automation with the flexibility and productivity demanded by competitive, worldwide manufacturing.

  2. Simplified Models for LHC New Physics Searches

    International Nuclear Information System (INIS)

    This document proposes a collection of simplified models relevant to the design of new-physics searches at the LHC and the characterization of their results. Both ATLAS and CMS have already presented some results in terms of simplified models, and we encourage them to continue and expand this effort, which supplements both signature-based results and benchmark model interpretations. A simplified model is defined by an effective Lagrangian describing the interactions of a small number of new particles. Simplified models can equally well be described by a small number of masses and cross-sections. These parameters are directly related to collider physics observables, making simplified models a particularly effective framework for evaluating searches and a useful starting point for characterizing positive signals of new physics. This document serves as an official summary of the results from the 'Topologies for Early LHC Searches' workshop, held at SLAC in September of 2010, the purpose of which was to develop a set of representative models that can be used to cover all relevant phase space in experimental searches. Particular emphasis is placed on searches relevant for the first ∼ 50-500 pb-1 of data and those motivated by supersymmetric models. This note largely summarizes material posted at http://lhcnewphysics.org/, which includes simplified model definitions, Monte Carlo material, and supporting contacts within the theory community. We also comment on future developments that may be useful as more data is gathered and analyzed by the experiments.

  3. Simplified Models for LHC New Physics Searches

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Daniele; /SLAC; Arkani-Hamed, Nima; /Princeton, Inst. Advanced Study; Arora, Sanjay; /Rutgers U., Piscataway; Bai, Yang; /SLAC; Baumgart, Matthew; /Johns Hopkins U.; Berger, Joshua; /Cornell U., Phys. Dept.; Buckley, Matthew; /Fermilab; Butler, Bart; /SLAC; Chang, Spencer; /Oregon U. /UC, Davis; Cheng, Hsin-Chia; /UC, Davis; Cheung, Clifford; /UC, Berkeley; Chivukula, R.Sekhar; /Michigan State U.; Cho, Won Sang; /Tokyo U.; Cotta, Randy; /SLAC; D' Alfonso, Mariarosaria; /UC, Santa Barbara; El Hedri, Sonia; /SLAC; Essig, Rouven, (ed.); /SLAC; Evans, Jared A.; /UC, Davis; Fitzpatrick, Liam; /Boston U.; Fox, Patrick; /Fermilab; Franceschini, Roberto; /LPHE, Lausanne /Pittsburgh U. /Argonne /Northwestern U. /Rutgers U., Piscataway /Rutgers U., Piscataway /Carleton U. /CERN /UC, Davis /Wisconsin U., Madison /SLAC /SLAC /SLAC /Rutgers U., Piscataway /Syracuse U. /SLAC /SLAC /Boston U. /Rutgers U., Piscataway /Seoul Natl. U. /Tohoku U. /UC, Santa Barbara /Korea Inst. Advanced Study, Seoul /Harvard U., Phys. Dept. /Michigan U. /Wisconsin U., Madison /Princeton U. /UC, Santa Barbara /Wisconsin U., Madison /Michigan U. /UC, Davis /SUNY, Stony Brook /TRIUMF; /more authors..

    2012-06-01

    This document proposes a collection of simplified models relevant to the design of new-physics searches at the LHC and the characterization of their results. Both ATLAS and CMS have already presented some results in terms of simplified models, and we encourage them to continue and expand this effort, which supplements both signature-based results and benchmark model interpretations. A simplified model is defined by an effective Lagrangian describing the interactions of a small number of new particles. Simplified models can equally well be described by a small number of masses and cross-sections. These parameters are directly related to collider physics observables, making simplified models a particularly effective framework for evaluating searches and a useful starting point for characterizing positive signals of new physics. This document serves as an official summary of the results from the 'Topologies for Early LHC Searches' workshop, held at SLAC in September of 2010, the purpose of which was to develop a set of representative models that can be used to cover all relevant phase space in experimental searches. Particular emphasis is placed on searches relevant for the first {approx} 50-500 pb{sup -1} of data and those motivated by supersymmetric models. This note largely summarizes material posted at http://lhcnewphysics.org/, which includes simplified model definitions, Monte Carlo material, and supporting contacts within the theory community. We also comment on future developments that may be useful as more data is gathered and analyzed by the experiments.

  4. An automated swimming respirometer

    DEFF Research Database (Denmark)

    STEFFENSEN, JF; JOHANSEN, K; BUSHNELL, PG

    1984-01-01

    An automated respirometer is described that can be used for computerized respirometry of trout and sharks.......An automated respirometer is described that can be used for computerized respirometry of trout and sharks....

  5. Configuration Management Automation (CMA)

    Data.gov (United States)

    Department of Transportation — Configuration Management Automation (CMA) will provide an automated, integrated enterprise solution to support CM of FAA NAS and Non-NAS assets and investments. CMA...

  6. Workflow automation architecture standard

    Energy Technology Data Exchange (ETDEWEB)

    Moshofsky, R.P.; Rohen, W.T. [Boeing Computer Services Co., Richland, WA (United States)

    1994-11-14

    This document presents an architectural standard for application of workflow automation technology. The standard includes a functional architecture, process for developing an automated workflow system for a work group, functional and collateral specifications for workflow automation, and results of a proof of concept prototype.

  7. Reload safety analysis automation tools

    International Nuclear Information System (INIS)

    Performing core physics calculations for the sake of reload safety analysis is a very demanding and time consuming process. This process generally begins with the preparation of libraries for the core physics code using a lattice code. The next step involves creating a very large set of calculations with the core physics code. Lastly, the results of the calculations must be interpreted, correctly applying uncertainties and checking whether applicable limits are satisfied. Such a procedure requires three specialized experts. One must understand the lattice code in order to correctly calculate and interpret its results. The next expert must have a good understanding of the physics code in order to create libraries from the lattice code results and to correctly define all the calculations involved. The third expert must have a deep knowledge of the power plant and the reload safety analysis procedure in order to verify, that all the necessary calculations were performed. Such a procedure involves many steps and is very time consuming. At ÚJV Řež, a.s., we have developed a set of tools which can be used to automate and simplify the whole process of performing reload safety analysis. Our application QUADRIGA automates lattice code calculations for library preparation. It removes user interaction with the lattice code and reduces his task to defining fuel pin types, enrichments, assembly maps and operational parameters all through a very nice and user-friendly GUI. The second part in reload safety analysis calculations is done by CycleKit, a code which is linked with our core physics code ANDREA. Through CycleKit large sets of calculations with complicated interdependencies can be performed using simple and convenient notation. CycleKit automates the interaction with ANDREA, organizes all the calculations, collects the results, performs limit verification and displays the output in clickable html format. Using this set of tools for reload safety analysis simplifies

  8. Simplified aerosol modeling for variational data assimilation

    Directory of Open Access Journals (Sweden)

    F. Chevallier

    2009-06-01

    Full Text Available We have developed a simplified aerosol model together with its tangent linear and adjoint versions for variational assimilation of aerosol optical depth with the aim to optimize aerosol emissions over the globe. The model was derived from the general circulation model LMDz; it groups together the 24 aerosol species simulated in LMDz into 4 species, namely gaseous precursors, fine mode aerosols, coarse mode desert dust and coarse mode sea salt. The emissions have been kept as in the original model. Modifications, however, were introduced in the computation of aerosol optical depth and in the processes of sedimentation, dry and wet deposition and sulfur chemistry to ensure consistency with the new set of species and their composition.

    The simplified model successfully manages to reproduce the main features of the aerosol distribution in LMDz. Differences between the original and simplified models are mainly associated to the new deposition and sedimentation velocities consistent with the definition of species in the simplified model and the simplification of the sulfur chemistry. Furthermore, simulated aerosol optical depth remains within the variability of AERONET observations for all aerosol types and all sites throughout most of the year.

    Sensitivity analyses with the tangent linear version show that the simplified sulfur chemistry is the dominant process responsible for the strong non-linearity of the model.

  9. SOFTWARE TEST AUTOMATION IN PRACTICE: EMPIRICAL STUDY FROM SRI LANKA

    Directory of Open Access Journals (Sweden)

    S. Hushalini

    2015-10-01

    Full Text Available In today, software projects are more complex than ever before, bugs are found before the product released and always creep in and often reappear. The Objective of the automated testing is to simplify as much of the testing effort as possible with minimum scripts. Automated software testing is the best way to increase the effectiveness, efficiency and coverage of software testing for software projects and also enables an organization to influence technology to perform tedious repetitive tasks efficiently, saving both time and cost, Along with that it gives more time to create test and increasing overall test coverage. The Current Literature suggests that nowadays it is very noticeable when considering the number of companies investing in automated testing tools due to the increased importance of Test Automation in software engineering. This paper will focus on how software test automation is in practice of today’s Sri Lankan’s software developments projects and will present the empirical observations. The objective of this empirical study is to shed light on the problems and the limitations in using the test automation tools and to figure out how test automation in Sri Lanka utilizes it significant key roles to succeed in software development projects in managing the mundane tasks. This paper can be used in future as a reference to obtain the knowledge and the findings of Test Automation use in Sri Lanka for early adopters.

  10. Software Test Automation in Practice: Empirical Study from Sri Lanka

    Directory of Open Access Journals (Sweden)

    S.Hushalini

    2014-11-01

    Full Text Available In today, software projects are more complex than ever before, bugs are found before the product released and always creep in and often reappear. The Objective of the automated testing is to simplify as much of the testing effort as possible with minimum scripts. Automated software testing is the best way to increase the effectiveness, efficiency and coverage of software testing for software projects and also enables an organization to influence technology to perform tediousrepetitive tasks efficiently, saving both time and cost, Along with that it gives more time to create test and increasing overall test coverage. The Current Literature suggests that nowadays it is very noticeable when considering the number of companies investing in automated testing tools due to the increased importance of Test Automation in software engineering. This paper will focus on how software test automation is in practice of today’s Sri Lankan’s software developments projects and will present the empirical observations. The objective of this empirical study is to shed light on the problems and the limitations in using the test automation tools and to figure out how test automation in Sri Lanka utilizes it significant key roles to succeed insoftware development projects in managing the mundane tasks. This paper can be used in future as a reference to obtain the knowledge and the findings of Test Automation use in Sri Lanka for early adopters.

  11. Shoe-String Automation

    Energy Technology Data Exchange (ETDEWEB)

    Duncan, M.L.

    2001-07-30

    Faced with a downsizing organization, serious budget reductions and retirement of key metrology personnel, maintaining capabilities to provide necessary services to our customers was becoming increasingly difficult. It appeared that the only solution was to automate some of our more personnel-intensive processes; however, it was crucial that the most personnel-intensive candidate process be automated, at the lowest price possible and with the lowest risk of failure. This discussion relates factors in the selection of the Standard Leak Calibration System for automation, the methods of automation used to provide the lowest-cost solution and the benefits realized as a result of the automation.

  12. Simplified models for exotic BSM searches

    Science.gov (United States)

    Heisig, Jan; Lessa, Andre; Quertenmont, Loic

    2015-12-01

    Simplified models are a successful way of interpreting current LHC searches for models beyond the standard model (BSM). So far simplified models have focused on topologies featuring a missing transverse energy (MET) signature. However, in some BSM theories other, more exotic, signatures occur. If a charged particle becomes long-lived on collider time scales — as it is the case in parts of the SUSY parameter space — it leads to a very distinct signature. We present an extension of the computer package SModelS which includes simplified models for heavy stable charged particles (HSCP). As a physical application we investigate the CMSSM stau co-annihilation strip containing long-lived staus, which presents a potential solution to the Lithium problem. Applying both MET and HSCP constraints we show that, for low values of tan β, all this region of parameter space either violates Dark Matter constraints or is excluded by LHC searches.

  13. Simplified Models for Exotic BSM Searches

    CERN Document Server

    Heisig, Jan; Quertenmont, Loic

    2015-01-01

    Simplified models are a successful way of interpreting current LHC searches for models beyond the standard model (BSM). So far simplified models have focused on topologies featuring a missing transverse energy (MET) signature. However, in some BSM theories other, more exotic, signatures occur. If a charged particle becomes long-lived on collider time scales - as it is the case in parts of the SUSY parameter space - it leads to a very distinct signature. We present an extension of the computer package SModelS which includes simplified models for heavy stable charged particles (HSCP). As a physical application we investigate the CMSSM stau co-annihilation strip containing long-lived staus, which presents a potential solution to the Lithium problem. Applying both MET and HSCP constraints we show that, for low values of $\\tan\\beta$, all this region of parameter space either violates Dark Matter constraints or is excluded by LHC searches.

  14. Simplified design of switching power supplies

    CERN Document Server

    Lenk, John

    1996-01-01

    Simplified Design of Switching Power Supplies is an all-inclusive, one-stop guide to switching power-supply design. Step-by-step instructions and diagrams render this book essential for the student and the experimenter, as well as the design professional.Simplified Design of Switching Power Supplies concentrates on the use of IC regulators. All popular forms of switching supplies, including DC-DC converters, inverters, buck, boost, buck-boost, pulse frequency modulation, pulse width modulation, current-mode control and pulse skipping, are described in detail. The design examples may

  15. Simplified design of switching power supplies

    CERN Document Server

    Lenk, John

    1995-01-01

    * Describes the operation of each circuit in detail * Examines a wide selection of external components that modify the IC package characteristics * Provides hands-on, essential information for designing a switching power supply Simplified Design of Switching Power Supplies is an all-inclusive, one-stop guide to switching power-supply design. Step-by-step instructions and diagrams render this book essential for the student and the experimenter, as well as the design professional. Simplified Design of Switching Power Supplies concentrates on the use of IC regulators. All popular forms of swit

  16. Simplified vibratory characterization of alluvial basins

    CERN Document Server

    Semblat, Jean-François; Duval, Anne-Marie

    2011-01-01

    For the analysis of seismic wave amplification, modal methods are interesting tools to study the modal properties of geological structures. Modal approaches mainly lead to information on such parameters as fundamental frequencies and eigenmodes of alluvial basins. For a specific alluvial deposit in Nice (France), a simplified modal approach involving the Rayleigh method is considered. This approach assumes a set of admissible shape functions for the eigenmodes and allows a fast estimation of the fundamental frequency of the basin. The agreement between modal numerical results and experimental ones is satisfactory. The simplified modal method then appears as an efficient mean for the global vibratory characterization of geological structures towards resonance.

  17. Simplified design of micropower and battery circuits

    CERN Document Server

    Lenk, John

    1995-01-01

    'Simplified Design of Micropower and Battery Circuits' provides a simplified, step-by-step approach to micropower and supply cell circuit design. No previous experience in design is required to use the techniques described, thus making the book well suited for the beginner, student, or experimenter as well as the design professional.The book concentrates on the use of commercial micropower ICs by discussing selections of external components that modify the IC-package characteristics. The basic approach is to start design problems with approximations for trial-value components in expe

  18. A simplified Capital Asset Pricing Model

    OpenAIRE

    Vovk, Vladimir

    2011-01-01

    We consider a Black-Scholes market in which a number of stocks and an index are traded. The simplified Capital Asset Pricing Model is the conjunction of the usual Capital Asset Pricing Model, or CAPM, and the statement that the appreciation rate of the index is equal to its squared volatility plus the interest rate. (The mathematical statement of the conjunction is simpler than that of the usual CAPM.) Our main result is that either we can outperform the index or the simplified CAPM holds.

  19. Heavy Flavor Simplified Models at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Essig, Rouven; /YITP, Stony Brook /Princeton, Inst. Advanced Study /SLAC; Izaguirre, Eder; /SLAC /Stanford U., Phys. Dept.; Kaplan, Jared; Wacker, Jay G.; /SLAC

    2012-04-03

    We consider a comprehensive set of simplified models that contribute to final states with top and bottom quarks at the LHC. These simplified models are used to create minimal search strategies that ensure optimal coverage of new heavy flavor physics involving the pair production of color octets and triplets. We provide a set of benchmarks that are representative of model space, which can be used by experimentalists to perform their own optimization of search strategies. For data sets larger than 1 fb{sup -1}, same-sign dilepton and 3b search regions become very powerful. Expected sensitivities from existing and optimized searches are given.

  20. Voxel-based morphometry in the detection of gray matter changes in temporal lobe epilepsy without abnormal on MRI%基于体素的形态学测量无常规MR异常的颞叶癫痫的灰质改变

    Institute of Scientific and Technical Information of China (English)

    何明颖; 杨毅; 汤丽华; 马成; 冯晨; 穆允凤; 印弘

    2011-01-01

    Objective To analyze the morphological changes of the gray matter of temporal lobe epilepsy (TLE) by the voxel-based optimized morphometryf VBM) and the individual brain atlases using SPM. Methods Thirty cases with TLE and forty healthy controls subjects age and sex matched underwent brain MR imaging by the magnetization prepared rapid gradient echo sequence. Then the images were processed and the datas were analyzed by the voxel-based morphmetry in SPM5 and the individual brain atlases using SPM. SPSS16. 0 was used in statistical analysis. Results VBM revealed that the gray matter reduce in different extent in bilateral cingulum-ant gyrus,left cingulum-mid gyrus,left thalamus,bilateral post-central-gyrus,left ant-central-gyrus,right temporal-inf and left temporal-sup. The whole gray matter in epilepsy was less than that in the control,there were significantly statistical differences! P0. 05). Conclusion VBM and IBASPM display that the whole gray matters of TLE are reduced in epilepsy and the encephalic regions where the gray matter reduced , hint the main position of the seizure foci and provide the informations for clinical precise treatment.%目的 利用基于体素的形态学分析(voxel-based optimized morphometry,VBM)及基于统计参数图的个体脑结构分析(individual brain atlases using SPM,IBASPM)软件,分析无常规MR异常的颞叶癫痫患者全脑灰质结构的改变.方法 对30例颞叶癫痫患者及40例正常健康志愿者行全脑扫描,扫描序列为磁化快速梯度回波(magnetization prepared rapid gradient echo,MPRAGE)扫描序列,获得高分辨T1WI图像,数据分析采用以SPM5(statistical parametric mapping 5)软件包为基础的VBM及IBASPM技术进行处理,利用SPSS16.0分别进行统计学分析.结果 通过比较,VBM显示颞叶癫痫患者双侧扣带前回、右侧扣带中回、左侧丘脑、双侧中央后回、左侧中央前回、左侧颞上回及右侧颞下回不同程度的灰质体素值减少,癫痫

  1. An Empirical Evaluation of Automated Theorem Provers in Software Certification

    Science.gov (United States)

    Denney, Ewen; Fischer, Bernd; Schumann, Johann

    2004-01-01

    We describe a system for the automated certification of safety properties of NASA software. The system uses Hoare-style program verification technology to generate proof obligations which are then processed by an automated first-order theorem prover (ATP). We discuss the unique requirements this application places on the ATPs, focusing on automation, proof checking, and usability. For full automation, however, the obligations must be aggressively preprocessed and simplified, and we demonstrate how the individual simplification stages, which are implemented by rewriting, influence the ability of the ATPs to solve the proof tasks. Our results are based on 13 certification experiments that lead to more than 25,000 proof tasks which have each been attempted by Vampire, Spass, e-setheo, and Otter. The proofs found by Otter have been proof-checked by IVY.

  2. 氯胺酮依赖者的额叶灰质体积研究——基于体素的形态学研究( VBM)%Volumetric abnormalities of gray matter in ketamine dependent patients: a voxel based morphometry study

    Institute of Scientific and Technical Information of China (English)

    廖艳辉; 詹劲松; 王绪轶; 谌红献; 向小军; 刘铁桥; 陈晓岗; 郝伟

    2012-01-01

    Objective Using three - dimensional magnetic resonance imaging to assess volumetric abnormalities of grey matter in chronic ketamine dependent subjects. Methods We used voxel based morphometry in conjunction with statistical parametric mapping on the structural magnetic resonance images of ketamine - dependent (n =41) and drug -naive control individuals (n = 44) to assess differences between the two groups in gray matter volume. Results We found a decrease in gray matter volume in bilateral frontal (left superior frontal and right middle frontal) cortex of ketamine patients in comparison to controls ( P < 0. 05 corrected for multiple comparisons at cluster - level) . Also, we found that the duration (months) of ketamine use was negatively correlated with gray matter volume in bilateral frontal cortex while the estimated total lifetime ketamine consumption was only negatively correlated with gray matter volume in left superior frontal cortex. Conclusions This is the first voxel - based morphometry study showing reduction of frontal gray matter volume in patients with ketamine dependence and showing the correlation of duration of ketamine use and cumulative doses of ketamine with decrease of frontal gray matter volume. Brain structural study of the affected areas in patients with ketamine dependence might better guide future research into the poorly understood condition of ketamine addiction and its correlates of schizophrenia.%目的 研究慢性氯胺酮依赖者脑灰质改变情况.方法 采用基本体素的形态学分析方法 对41名氯胺酮依赖者和44名未使用任何成瘾物质的健康志愿者进行两组之间的脑灰质体积比较.结果 与对照组相比,氯胺酮依赖组的双侧额叶区(左额上回和右额中回)灰质体积下降(P <0.05,纠正后,cluster水平);氯胺酮使用的时间(月)与双侧额叶灰质体积呈负相关,而估计的氯胺酮使用总量只和左额上回的灰质体积呈负相关.结论 本研究首次

  3. Study of Gray Matter Loss in Alzheimer's Disease Based on Automatic Voxel-based Morphometry%应用全脑逐像素形态学自动分析方法研究阿尔茨海默氏病的灰质缺失

    Institute of Scientific and Technical Information of China (English)

    闫镔; 王葳; 刘华; 李坤成; 李可; 单保慈; 唐孝威

    2006-01-01

    Objective To explore the gray matter loss of Alzheimer's disease (AD) patients by processing the magnetic resonance imaging (MRI) with computer. Method A voxel-based morphometry (VBM) method was applied in this study. Result Bilateral loss of gray matter in AD patients was found in the entorhinal/ hippocampal/parahippocampal cortex areas, amygdala, the head of the caudate nucleus, middle temporal gyrus, cingulate gyrus, inferior parietal lobule, insula and dorsolateral prefrontal cortex. Furthermore, area of right pulvinar, cortex of superior temporal gyrus and superior parietal lobule reduced significantly. On the other hand, somatosensory/motor cortex, cerebellum and occipital lobe were relatively intact. Conclusion VBM overcomes the shortcomings of region of interesting(ROI), such as time-consuming, dependence on observer, and poorly reproducible, and can analyze the gray matter loss objectively and automatically and have a good perspective for clinical applications.%目的采用计算机处理核磁共振图像(magnetic resonance imaging, MRI), 研究阿尔茨海默氏病(Alzheimer's disease, AD)患者的灰质萎缩区域.方法采用逐像素形态学(voxel-based morphometry, VBM)方法.结果和正常老年人对照组相比,AD病人的海马、海马旁回、内嗅皮层、杏仁体、尾状核头部、颞中回、扣带回、顶下小叶、岛叶和前额叶背外侧区双侧萎缩;右侧丘脑枕、颞上回、顶上小叶不同程度萎缩,而感觉运动皮层、小脑和枕叶相对保持完好.结论 VBM方法克服了以往使用人工勾画感兴趣区(ROI)方法的可重复性差,费时等缺点,可以客观、自动和全面地分析AD的灰质减少,具有良好的临床应用前景.

  4. Deep Gray Matter and Limbic Lobe Atrophy in Multiple Sclerosis:a Voxel- based Morphometry Study%多发性硬化的深部灰质核团和边缘叶萎缩:基于体素的形态学研究

    Institute of Scientific and Technical Information of China (English)

    李郁欣; 张碧云; 汤伟军; 耿道颖

    2011-01-01

    目的:采用基于体素的形态学(VBM)方法探讨多发性硬化患者的脑灰质变化.方法:应用3.0T MRI,对25例复发缓解型多发性硬化(RRMS)患者和22例正常志愿者进行3D T1WI扫描,通过基于体素的形态学分析全脑灰质和区域灰质核团的变化.结果:与正常对照组比较,多发性硬化的全脑灰质明显萎缩( 679.40±52.68mlvs629.09±54.50ml,P=0.040),其中双侧丘脑、双侧壳核、双侧苍白球、左侧尾状核、左侧海马、左侧海马旁回、双侧扣带回前部、右侧颞上回、右侧颞中回、双侧岛叶体积明显缩小(P< 0.001).结论:多发性硬化存在脑灰质萎缩,主要累及深部灰质核团和边缘叶系统.%Purpose: To analyze the gray matter volume changes in multiple sclerosis patients by means of voxel - based morphometry. Methods: Three - dimensional Ti weighted images were obtained from 25 patients with relapsing - remitting multiple sclerosis (RRMS) and 22 matched healthy controls on a 3.0T MRI machine. Voxel - based morphometry was used to analyze the atrophy of the whole and regional gray matter changes. Results: When compared with controls, the patients with MS showed the presence of significant gray matter atrophy (679.40 ± 52.68ml vs 629.09 ± 54. 50ml, P = 0.040), and the volumes of bilateral thalami,bilateral putamen nuclei, bilateral globus pallidum, left caudate nuclei, left hippocampus, left parahippocampal gyrus, bilateral anterior cingulate gyrus, right superior temporal gyms, right middle temporal gyrus and bilateral insula were significantly reduced(P< 0.001) .Conclusion: Gray matter atrophy is exist with multiple sclerosis, and mainly involves the deep gray nuclei and limbic system.

  5. 77 FR 54482 - Allocation of Costs Under the Simplified Methods

    Science.gov (United States)

    2012-09-05

    ... Internal Revenue Service 26 CFR Part 1 RIN 1545-BG07 Allocation of Costs Under the Simplified Methods... under the simplified production method or the simplified resale method. The proposed regulations provide... allocation of costs under the simplified methods of accounting under section 263A of the Internal...

  6. Heterogeneous Computing in Economics: A Simplified Approach

    OpenAIRE

    Dziubinski, Matt P.; Grassi, Stefano

    2012-01-01

    This paper shows the potential of heterogeneous computing in solving dynamic equilibrium models in economics. We illustrate the power and simplicity of the C++ Accelerated Massive Parallelism recently introduced by Microsoft. Starting from the same exercise as Aldrich et al. (2011) we document a speed gain together with a simplified programming style that naturally enables parallelization.

  7. Simplified differential equations approach for Master Integrals

    OpenAIRE

    Papadopoulos, Costas G.

    2014-01-01

    A simplified differential equations approach for Master Integrals is presented. It allows to express them, straightforwardly, in terms of Goncharov Polylogarithms. As a proof-of-concept of the proposed method, results at one and two loops are presented, including the massless one-loop pentagon with up to one off-shell leg at order epsilon.

  8. Identifying Requirements for Effective Human-Automation Teamwork

    Energy Technology Data Exchange (ETDEWEB)

    Jeffrey C. Joe; John O' Hara; Heather D. Medema; Johanna H. Oxstrand

    2014-06-01

    Previous studies have shown that poorly designed human-automation collaboration, such as poorly designed communication protocols, often leads to problems for the human operators, such as: lack of vigilance, complacency, and loss of skills. These problems often lead to suboptimal system performance. To address this situation, a considerable amount of research has been conducted to improve human-automation collaboration and to make automation function better as a “team player.” Much of this research is based on an understanding of what it means to be a good team player from the perspective of a human team. However, the research is often based on a simplified view of human teams and teamwork. In this study, we sought to better understand the capabilities and limitations of automation from the standpoint of human teams. We first examined human teams to identify the principles for effective teamwork. We next reviewed the research on integrating automation agents and human agents into mixed agent teams to identify the limitations of automation agents to conform to teamwork principles. This research resulted in insights that can lead to more effective human-automation collaboration by enabling a more realistic set of requirements to be developed based on the strengths and limitations of all agents.

  9. Automated stopcock actuator

    OpenAIRE

    Vandehey, N. T.; O'Neil, J.P.

    2015-01-01

    Introduction We have developed a low-cost stopcock valve actuator for radiochemistry automation built using a stepper motor and an Arduino, an open-source single-board microcontroller. The con-troller hardware can be programmed to run by serial communication or via two 5–24 V digital lines for simple integration into any automation control system. This valve actuator allows for automated use of a single, disposable stopcock, providing a number of advantages over stopcock manifold systems ...

  10. The Adaptive Automation Design

    OpenAIRE

    Calefato, Caterina; Montanari, Roberto; TESAURI, Francesco

    2008-01-01

    After considering the positive effects of adaptive automation implementation, this chapter focuses on two partly overlapping phenomena: on the one hand, the role of trust in automation is considered, particularly as to the effects of overtrust and mistrust in automation's reliability; on the other hand, long-term lack of exercise on specific operation may lead users to skill deterioration. As a future work, it will be interesting and challenging to explore the conjunction of adaptive automati...

  11. Service functional test automation

    OpenAIRE

    Hillah, Lom Messan; Maesano, Ariele-Paolo; Rosa, Fabio; Maesano, Libero; Lettere, Marco; Fontanelli, Riccardo

    2015-01-01

    This paper presents the automation of the functional test of services (black-box testing) and services architectures (grey-box testing) that has been developed by the MIDAS project and is accessible on the MIDAS SaaS. In particular, the paper illustrates the solutions of tough functional test automation problems such as: (i) the configuration of the automated test execution system against large and complex services architectures, (ii) the constraint-based test input generation, (iii) the spec...

  12. Automated Weather Observing System

    Data.gov (United States)

    Department of Transportation — The Automated Weather Observing System (AWOS) is a suite of sensors, which measure, collect, and disseminate weather data to help meteorologists, pilots, and flight...

  13. Laboratory Automation and Middleware.

    Science.gov (United States)

    Riben, Michael

    2015-06-01

    The practice of surgical pathology is under constant pressure to deliver the highest quality of service, reduce errors, increase throughput, and decrease turnaround time while at the same time dealing with an aging workforce, increasing financial constraints, and economic uncertainty. Although not able to implement total laboratory automation, great progress continues to be made in workstation automation in all areas of the pathology laboratory. This report highlights the benefits and challenges of pathology automation, reviews middleware and its use to facilitate automation, and reviews the progress so far in the anatomic pathology laboratory. PMID:26065792

  14. Automated cloning methods.; TOPICAL

    International Nuclear Information System (INIS)

    Argonne has developed a series of automated protocols to generate bacterial expression clones by using a robotic system designed to be used in procedures associated with molecular biology. The system provides plate storage, temperature control from 4 to 37 C at various locations, and Biomek and Multimek pipetting stations. The automated system consists of a robot that transports sources from the active station on the automation system. Protocols for the automated generation of bacterial expression clones can be grouped into three categories (Figure 1). Fragment generation protocols are initiated on day one of the expression cloning procedure and encompass those protocols involved in generating purified coding region (PCR)

  15. Do We Really Need to Calibrate All the Parameters? Variance-Based Sensitivity Analysis to Simplify Microscopic Traffic Flow Models

    OpenAIRE

    PUNZO VINCENZO; MONTANINO, Marcello; CIUFFO BIAGIO

    2014-01-01

    Automated calibration of microscopic traffic flow models is all but simple for a number of reasons, including the computational complexity of black-box optimization and the asymmetric importance of parameters in influencing model performances. The main objective of this paper is therefore to provide a robust methodology to simplify car-following models, that is, to reduce the number of parameters (to calibrate) without sensibly affecting the capability of reproducing reality. To this aim, var...

  16. An automated deformable image registration evaluation of confidence tool

    Science.gov (United States)

    Kirby, Neil; Chen, Josephine; Kim, Hojin; Morin, Olivier; Nie, Ke; Pouliot, Jean

    2016-04-01

    Deformable image registration (DIR) is a powerful tool for radiation oncology, but it can produce errors. Beyond this, DIR accuracy is not a fixed quantity and varies on a case-by-case basis. The purpose of this study is to explore the possibility of an automated program to create a patient- and voxel-specific evaluation of DIR accuracy. AUTODIRECT is a software tool that was developed to perform this evaluation for the application of a clinical DIR algorithm to a set of patient images. In brief, AUTODIRECT uses algorithms to generate deformations and applies them to these images (along with processing) to generate sets of test images, with known deformations that are similar to the actual ones and with realistic noise properties. The clinical DIR algorithm is applied to these test image sets (currently 4). From these tests, AUTODIRECT generates spatial and dose uncertainty estimates for each image voxel based on a Student’s t distribution. In this study, four commercially available DIR algorithms were used to deform a dose distribution associated with a virtual pelvic phantom image set, and AUTODIRECT was used to generate dose uncertainty estimates for each deformation. The virtual phantom image set has a known ground-truth deformation, so the true dose-warping errors of the DIR algorithms were also known. AUTODIRECT predicted error patterns that closely matched the actual error spatial distribution. On average AUTODIRECT overestimated the magnitude of the dose errors, but tuning the AUTODIRECT algorithms should improve agreement. This proof-of-principle test demonstrates the potential for the AUTODIRECT algorithm as an empirical method to predict DIR errors.

  17. Development of a simplified biofilm model

    Science.gov (United States)

    Sarkar, Sushovan; Mazumder, Debabrata

    2015-11-01

    A simplified approach for analyzing the biofilm process in deriving an easy model has been presented. This simplified biofilm model formulated correlations between substrate concentration in the influent/effluent and at biofilm-liquid interface along with substrate flux and biofilm thickness. The model essentially considered the external mass transport according to Fick's Law, steady state substrate as well as biomass balance for attached growth microorganisms. In substrate utilization, Monod growth kinetics has been followed incorporating relevant boundary conditions at the liquid-biofilm interface and at the attachment surface. The numerical solution of equations was accomplished using Runge-Kutta method and accordingly an integrated computer program was developed. The model has been successfully applied in a distinct set of trials with varying range of representative input variables. The model performance was compared with available existing methods and it was found an easy, accurate method that can be used for process design of biofilm reactor.

  18. Pattern Classification using Simplified Neural Networks

    CERN Document Server

    Kamruzzaman, S M

    2010-01-01

    In recent years, many neural network models have been proposed for pattern classification, function approximation and regression problems. This paper presents an approach for classifying patterns from simplified NNs. Although the predictive accuracy of ANNs is often higher than that of other methods or human experts, it is often said that ANNs are practically "black boxes", due to the complexity of the networks. In this paper, we have an attempted to open up these black boxes by reducing the complexity of the network. The factor makes this possible is the pruning algorithm. By eliminating redundant weights, redundant input and hidden units are identified and removed from the network. Using the pruning algorithm, we have been able to prune networks such that only a few input units, hidden units and connections left yield a simplified network. Experimental results on several benchmarks problems in neural networks show the effectiveness of the proposed approach with good generalization ability.

  19. A simplified genetic design for mammalian enamel

    OpenAIRE

    Snead, ML; Zhu, D.; Lei, YP.; Luo, W.; Bringas, P.; Sucov, H.; Rauth, RJ; Paine, ML; White, SN

    2011-01-01

    A biomimetic replacement for tooth enamel is urgently needed because dental caries is the most prevalent infectious disease to affect man. Here, design specifications for an enamel replacement material inspired by Nature are deployed for testing in an animal model. Using genetic engineering we created a simplified enamel protein matrix precursor where only one, rather than dozens of amelogenin isoforms, contributed to enamel formation. Enamel function and architecture were unaltered, but the ...

  20. Simplified dichromated gelatin hologram recording process

    Science.gov (United States)

    Georgekutty, Tharayil G.; Liu, Hua-Kuang

    1987-01-01

    A simplified method for making dichromated gelatin (DCG) holographic optical elements (HOE) has been discovered. The method is much less tedious and it requires a period of processing time comparable with that for processing a silver halide hologram. HOE characteristics including diffraction efficiency (DE), linearity, and spectral sensitivity have been quantitatively investigated. The quality of the holographic grating is very high. Ninety percent or higher diffraction efficiency has been achieved in simple plane gratings made by this process.

  1. The simplified version of the program EAVEK

    OpenAIRE

    Celarec, Daniel

    2007-01-01

    The simplified version of the program EAVEK has been developed in the MATLAB programming language. Theoretical backgrounds of the new program are based on the program EAVEK. However, some new capabilities are added in the program. Therefore, the new program automatically checks the irregularity in plan and considers accidental torsion and second-order effects according to Eurocode 8. In addition, it is also possible to add new macro-elements in the program. The algorithm, the c...

  2. Development of a simplified piping support system

    International Nuclear Information System (INIS)

    This paper presents the results of experimental and analytical studies for developing a simplified piping support system (SPSS) for nuclear power piping in place of snubbers. The basic concept of the SPSS is a passive seismic support system consisting of limit stops. Large gaps are provided to allow for free thermal expansion during normal plant operation while preventing excessive displacement during a seismic event. The results are part of a research and development program sponsored by EPRI. (orig./HP)

  3. European simplified boiling water reactor (ESBWR) plant

    International Nuclear Information System (INIS)

    This paper covers innovative ideas which made possible the redesign of the US 660-MW Simplified Boiling Water Reactor (SBWR) Reactor Island for a 1,200-MW size reactor while actually reducing the building cost. This was achieved by breaking down the Reactor Island into multiple buildings separating seismic-1 from non-seismic-1 areas, providing for better space utilization, shorter construction schedule, easier maintainability and better postaccident accessibility

  4. Simplified Linear Multivariable Control Of Robots

    Science.gov (United States)

    Seraji, Homayoun

    1989-01-01

    Simplified method developed to design control system that makes joints of robot follow reference trajectories. Generic design includes independent multivariable feedforward and feedback controllers. Feedforward controller based on inverse of linearized model of dynamics of robot and implements control law that contains only proportional and first and second derivatives of reference trajectories with respect to time. Feedback controller, which implements control law of proportional, first-derivative, and integral terms, makes tracking errors converge toward zero as time passes.

  5. A Simplified Spice Model for IGBT

    OpenAIRE

    Haddi, A.; Maouad, A.; Elmazria, O.; Hoffmann, A; Charles, J. P.

    1998-01-01

    A simplified IGBT (Insulated Gate Bipolar Transistor) SPICE macromodel, based on its equivalent circuit, is proposed. This macromodel is provided to simulate various mechanisms governing the behavior of the IGBT, and it takes into account specific phenomena limiting its SOA (Safe Operating Area), such as forward and reverse biased SOA, as well as latch-up. The validity of this model is confirmed by comparison between simulation and experimental results as well as the data sheet...

  6. Library Automation Style Guide.

    Science.gov (United States)

    Gaylord Bros., Liverpool, NY.

    This library automation style guide lists specific terms and names often used in the library automation industry. The terms and/or acronyms are listed alphabetically and each is followed by a brief definition. The guide refers to the "Chicago Manual of Style" for general rules, and a notes section is included for the convenience of individual…

  7. Automation in Warehouse Development

    NARCIS (Netherlands)

    Hamberg, R.; Verriet, J.

    2012-01-01

    The warehouses of the future will come in a variety of forms, but with a few common ingredients. Firstly, human operational handling of items in warehouses is increasingly being replaced by automated item handling. Extended warehouse automation counteracts the scarcity of human operators and support

  8. Automate functional testing

    Directory of Open Access Journals (Sweden)

    Ramesh Kalindri

    2014-06-01

    Full Text Available Currently, software engineers are increasingly turning to the option of automating functional tests, but not always have successful in this endeavor. Reasons range from low planning until over cost in the process. Some principles that can guide teams in automating these tests are described in this article.

  9. Automation in Immunohematology

    Directory of Open Access Journals (Sweden)

    Meenu Bajpai

    2012-01-01

    Full Text Available There have been rapid technological advances in blood banking in South Asian region over the past decade with an increasing emphasis on quality and safety of blood products. The conventional test tube technique has given way to newer techniques such as column agglutination technique, solid phase red cell adherence assay, and erythrocyte-magnetized technique. These new technologies are adaptable to automation and major manufacturers in this field have come up with semi and fully automated equipments for immunohematology tests in the blood bank. Automation improves the objectivity and reproducibility of tests. It reduces human errors in patient identification and transcription errors. Documentation and traceability of tests, reagents and processes and archiving of results is another major advantage of automation. Shifting from manual methods to automation is a major undertaking for any transfusion service to provide quality patient care with lesser turnaround time for their ever increasing workload. This article discusses the various issues involved in the process.

  10. Automated model building

    CERN Document Server

    Caferra, Ricardo; Peltier, Nicholas

    2004-01-01

    This is the first book on automated model building, a discipline of automated deduction that is of growing importance Although models and their construction are important per se, automated model building has appeared as a natural enrichment of automated deduction, especially in the attempt to capture the human way of reasoning The book provides an historical overview of the field of automated deduction, and presents the foundations of different existing approaches to model construction, in particular those developed by the authors Finite and infinite model building techniques are presented The main emphasis is on calculi-based methods, and relevant practical results are provided The book is of interest to researchers and graduate students in computer science, computational logic and artificial intelligence It can also be used as a textbook in advanced undergraduate courses

  11. Automation in Warehouse Development

    CERN Document Server

    Verriet, Jacques

    2012-01-01

    The warehouses of the future will come in a variety of forms, but with a few common ingredients. Firstly, human operational handling of items in warehouses is increasingly being replaced by automated item handling. Extended warehouse automation counteracts the scarcity of human operators and supports the quality of picking processes. Secondly, the development of models to simulate and analyse warehouse designs and their components facilitates the challenging task of developing warehouses that take into account each customer’s individual requirements and logistic processes. Automation in Warehouse Development addresses both types of automation from the innovative perspective of applied science. In particular, it describes the outcomes of the Falcon project, a joint endeavour by a consortium of industrial and academic partners. The results include a model-based approach to automate warehouse control design, analysis models for warehouse design, concepts for robotic item handling and computer vision, and auton...

  12. Advances in inspection automation

    Science.gov (United States)

    Weber, Walter H.; Mair, H. Douglas; Jansen, Dion; Lombardi, Luciano

    2013-01-01

    This new session at QNDE reflects the growing interest in inspection automation. Our paper describes a newly developed platform that makes the complex NDE automation possible without the need for software programmers. Inspection tasks that are tedious, error-prone or impossible for humans to perform can now be automated using a form of drag and drop visual scripting. Our work attempts to rectify the problem that NDE is not keeping pace with the rest of factory automation. Outside of NDE, robots routinely and autonomously machine parts, assemble components, weld structures and report progress to corporate databases. By contrast, components arriving in the NDT department typically require manual part handling, calibrations and analysis. The automation examples in this paper cover the development of robotic thickness gauging and the use of adaptive contour following on the NRU reactor inspection at Chalk River.

  13. Postured voxel-based human models for electromagnetic dosimetry

    International Nuclear Information System (INIS)

    High-resolution anatomically realistic whole-body voxel models have recently been developed for electromagnetic dosimetry. However, the posture of most models is similar to the standing one, which strongly limits electromagnetic dosimetry when simulating a realistic exposure scenario. In this paper, we present the development of postured models based on anatomically realistic voxel models with standing posture. Voxel models of the Japanese adult male and female were used as the original upright standing models. The Japanese models were composed of 2 mm cubic voxels, each of which was segmented into 51 different tissue types. We developed several different types of posture models using a novel posture transformation method. These posture models were smoothly transformed, while the continuity of the internal tissues and organs was maintained. In this paper, we also present our calculations of the whole-body averaged specific absorption rates (SARs) of sitting male and female models exposed to electromagnetic plane waves at very high (VHF) and ultra high frequency (UHF) bands.

  14. Schizotypy and brain structure: a voxel-based morphometry study

    NARCIS (Netherlands)

    Modinos, G.; Mechelli, A.; Ormel, J.; Groenewold, N.A.; Aleman, A.; McGuire, P.K.

    2010-01-01

    Background. Schizotypy is conceptualized as a subclinical manifestation of the same underlying biological factors that give rise to schizophrenia and other schizophrenia spectrum disorders. Individuals with psychometric schizotypy (PS) experience subthreshold psychotic signs and can be psychometrica

  15. Schizotypy and brain structure : a voxel-based morphometry study

    NARCIS (Netherlands)

    Modinos, G.; Mechelli, A.; Ormel, J.; Groenewold, N. A.; Aleman, A.; McGuire, P. K.

    2010-01-01

    Background. Schizotypy is conceptualized as a subclinical manifestation of the same underlying biological factors that give rise to schizophrenia and other schizophrenia spectrum disorders. Individuals with psychometric schizotypy (PS) experience subthreshold psychotic signs and can be psychometrica

  16. A voxel-based morphometric MRI study in psychopathic traits

    OpenAIRE

    Hiroki Fukui

    2008-01-01

    Purpose: Psychopathy is characterized by a failure to experience emotions that are necessary for appropriate social behavior, such as empathy. These characters are considered to construct a latent dimension rather than a latent taxon. Non-clinical individuals are relatively free of potentially confounding variables (e.g., severe substance use, physical abuse history) that can often complicate the interpretation of brain-imaging deficits. Our aim was to examine whether a specific association e...

  17. Voxel-based model and its application in advanced manufacturing

    Science.gov (United States)

    Wu, Xiaojun; Liu, Weijun; Wang, Tianran

    2004-03-01

    Traditionally, 3D models, even so called solid ones, can only represent the object's surface information, and the interior is regarded as homogeneous. In most applications, it is necessary to represent the interior structures and attributes of an object, such as materials, density and color, etc. Surface model is incapable of bearing this task. In this case, voxel model is a good choice. Voxelization is the process of converting a geometrically represented 3D object into a three dimensional volume of dataset. In this paper, an algorithm is proposed to voxelize the polygonal meshes ported from current CAD modeling packages into volume datasets based on the easily indexing property of Octree structure. The minimal distance to the feature voxel (or voxels) is taken as criterion to distribute different material compositions to get a new kind of material called FGM (functionally graded material), which is suitable for the interface of RPM (Rapid Prototyping Manufacturing).

  18. 运用VBM方法检测创伤后应激障碍患者发病前脑灰质容积的改变%Brain Structural Abnormalities Prior to the Onset of Post-Traumatic Stress Disorder: A Voxel-Based Morphometry Study

    Institute of Scientific and Technical Information of China (English)

    孙雅文; 王振; 周滟; 秦玲娣; 苏珊珊; 路青; 陈增爱; 许建荣

    2012-01-01

    Objective To delect the changes of gray matter volume (GMV) in patients with post-traumatic stress disor-der(PTSD) before the onset using voxel-based morphometiy( VBM). Methods All the subjects were scanned on a 3. OT MR system within 2 days after trauma exposed- The magnetic resonance imagings of the brain were acquired from 12 subjects who had PTSD in the end, as well as from 12 age-, gender- and traumatic events-matched healthy controls. Image preprocessing was carried out using VBM implemented on the Statistical Parametric Mapping (SPM5) software package. A second-level two-sample t-test was used to examine the differences of GMV between the two groups (P 35). Results Compared with controls, PTSD patients had lower GMV in the right amygdala, right parahippocampal gyrus, right anterior cingulate, right superior frontal gynis, right middle temporal gyrus, right inferior temporal gyrus, right precuneus, left inferior frontal gyrus, left superior temporal gyros, left insular, left precentral gyrus and left midbrain. No area of significantly decreased GMV was observed in controls in relative to PTSD patients. Conclusion As the changes of brain regions related to emotional control, regulation and memory functions can be identified in patients who go on to develop PTSD after recent trauma, these data could form part of the predisposition to develop PTSD.%目的 运用基于体素的形态学方法(voxel based morphometry,VBM)分析创伤后应激障碍(posttraumatic stress disorder,PTSD)患者是否于发病前即存在脑灰质容积的改变. 方法 PTSD危险人群于创伤暴露后2天内行3 T MRI全脑扫描.搜集12例最终确诊的PTSD患者及12例年龄、性别及创伤暴露与之相匹配的对照组的脑结构图像,运用基于SPM5的VBM5进行数据分析,采用双样本t检验,以P<0.001(未校正),核团体素>35视为差异有统计学意义.结果 与对照组相比,PTSD组右侧杏仁核、海马旁回、前扣带回、额上回、颞中回

  19. 应用基于体素的形态测量学方法分析原发性手震颤患者灰质体积变化%Brain gray matter changes in essential arm tremor patients:Voxel-based morphometry

    Institute of Scientific and Technical Information of China (English)

    曹红梅; 王蓉; 李贤军; 罗雪; 杨健; 屈秋民

    2015-01-01

    Objective To investigate the abnormalities of brain gray matter volume in patients with clinically-confirmed essential tremor (ET)of the hands only.Methods We analyzed brain gray matter voxel of 1 7 patients (younger than 55 years)with ET of the hands only and 1 7 healthy controls matched in age,gender and education by optimized voxel-based morphometry (VBM).Results VBM showed marked expansion of the bilateral cerebella, occipital fusiform cortices,and precentral lobes (P uncorrected < 0.005 )in ET patients compared with the controls. Atrophy was only detected in left parietal lobe.We also found volume enlargement in the thalamus,midbrain,and melluda of the left side by region of interest (ROI )analysis (P uncorrected <0.005).Conclusion Patients with arm tremor show expansion of gray matter,which might represent the adaptive reorganizational compensation through the increased demand on the visuospatial control of skilled movements in ET patients with early-stage arm tremor. These morphological changes may help to assess early stage and distinguish subtype of ET.%目的:评价单纯手震颤的原发性震颤(essential tremor,ET)患者脑内灰质体积变化。方法选取 l7例临床确诊的,年龄小于55岁的单纯手震颤 ET 患者及17名年龄、性别、教育程度匹配的正常对照者,行全脑三维快速扰相梯度回波(3D fast spoiled gradient echo,3D FSPGR)序列扫描,采用基于体素的形态测量学(voxel-based morphometry, VBM)分析方法,对 ET 患者及正常对照者的脑内灰质体素进行分析。结果与正常对照组相比,ET 患者脑内可见双侧小脑半球前叶、枕叶、颞叶及中央前回体积增大以及左侧顶叶体积缩小(P uncor ected <0.005);进一步的感兴趣区(region-of-interest,ROI)测定发现左侧丘脑、中脑及延髓体积膨大,桥脑体积缩小(P uncor ected <0.005)。结论应用VBM 方法对于单纯手震颤 ET 患者磁共振图像分析,能够客观揭示其脑内独特的灰

  20. Operator constraint principle for simplifying atmospheric dynamical equations

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Based on the qualitative theory of atmospheric dynamical equations, a new method for simplifying equations, the operator constraint principle, is presented. The general rule of the method and its mathematical strictness are discussed. Moreover, the way that how to use the method to simplify equations rationally and how to get the simplified equations with harmonious and consistent dynamics is given.

  1. Automated preliminary design of simplified wing structures to satisfy strength and flutter requirements

    Science.gov (United States)

    Stroud, W. J.; Dexter, C. B.; Stein, M.

    1972-01-01

    A simple structural model of an aircraft wing is used to show the effects of strength (stress) and flutter requirements on the design of minimum-weight aircraft-wing structures. The wing is idealized as an isotropic sandwich plate with a variable cover thickness distribution and a variable depth between covers. Plate theory is used for the structural analysis, and piston theory is used for the unsteady aerodynamics in the flutter analysis. Mathematical programming techniques are used to find the minimum-weight cover thickness distribution which satisfies flutter, strength, and minimum-gage constraints. The method of solution, some sample results, and the computer program used to obtain these results are presented. The results indicate that the cover thickness distribution obtained when designing for the strength requirement alone may be quite different from the cover thickness distribution obtained when designing for either the flutter requirement alone or for both the strength and flutter requirements concurrently. This conclusion emphasizes the need for designing for both flutter and strength from the outset.

  2. Simplified stock markets described by number operators

    Science.gov (United States)

    Bagarello, F.

    2009-06-01

    In this paper we continue our systematic analysis of the operatorial approach previously proposed in an economical context and we discuss a mixed toy model of a simplified stock market, i.e. a model in which the price of the shares is given as an input. We deduce the time evolution of the portfolio of the various traders of the market, as well as of other observable quantities. As in a previous paper, we solve the equations of motion by means of a fixed point like approximation.

  3. Appraisal of allowable loads by simplified rules

    International Nuclear Information System (INIS)

    This paper presents a simplified method of analysis of buckling of thin structures like those of L.M.F.B.R.'s. The edification of the method is very similar to methods used for buckling of beams and columns having initial geometric imperfections and buckling in the plastic range. Particular attention is paid to the stress hardening of material involved (austenitic steel) and to possible unstable post buckling of thin structures. The analysis method is based on elastic calculation and diagrams that take into account various initial geometric defects

  4. Simplified design of microprocessor-supervisory circuits

    CERN Document Server

    Lenk, John

    1998-01-01

    This is the seventh book in the popular Simplified Design series from John Lenk, which teaches engineers, technicians, and students to use and modify off-the-shelf ICs to suit their individual design needs.The first chapter of this book describes the basic operation of microprocessor supervisory circuits and how to use manufacturer data sheets to make your component selections. Later chapters describe the internal operations of various commonly-available ICs and how to select and modify them.The most common microprocessor-supervisory functions include: power-on reset, low-volta

  5. Simplified cryopreservation of porcine cloned blastocysts

    DEFF Research Database (Denmark)

    Du, Yutao; Zhang, Yunhai; Li, Juan;

    2007-01-01

    )â€"handmade cloning (HMC)â€"to establish a simplified and efficient cryopreservation system for porcine cloned embryos. In Experiment 1, zonae pellucidae of oocytes were partially digested with pronase, followed by centrifugation to polarize lipid particles. Ninety percent (173/192) oocytes were successfully......). Our results prove that porcine embryos produced from delipated oocytes by PA or HMC can be cryopreserved effectively by ultrarapid vitrification. Further experiments are required to assess the in vivo developmental competence of the cloned-vitrified embryos  ...

  6. Simplified calculation of detonation induced impulse

    International Nuclear Information System (INIS)

    Simplified methods of estimating the impulse generated by detonations propagating through gaseous fuel-oxidizer mixtures are developed. First the ground and dynamic impulse are defined. Self similar solutions are used to derive expressions for the ground and dynamic impulse of detonations confined clouds with plane, cylindrical, and spherical symmetry in terms of universal impulse functions which are independent of the detonation properties. A similar analysis is developed for clouds bounded by an inert gas which results in side relief. In this case the results are found to be in good agreement with experiment and with hydrocode calculations

  7. Simplified methodology for Angra 1 containment analysis

    International Nuclear Information System (INIS)

    A simplified methodology of analysis was developed to simulate a Large Break Loss of Coolant Accident in the Angra 1 Nuclear Power Station. Using the RELAP5/MOD1, RELAP4/MOD5 and CONTEMPT-LT Codes, the time variation of pressure and temperature in the containment was analysed. The obtained data was compared with the Angra 1 Final Safety Analysis Report, and too those calculated by a Detailed Model. The results obtained by this new methodology such as the small computational time of simulation, were satisfactory when getting the preliminary evaluation of the Angra 1 global parameters. (author)

  8. Simplified design procedure for base isolation system

    Energy Technology Data Exchange (ETDEWEB)

    Takayama, Mineo; Tada, Hideyuki [Fukuoka Univ. (Japan). Faculty of Engineering

    1995-12-01

    This paper presents a simplified design procedure which incorporates an existing response prediction method for base isolated buildings into design methods for isolation devices (rubber bearings and hysteresis dampers). The procedure enables a designer to easily identify the relationship between tile seismic behavior of base-isolated buildings and the characteristics of isolation devices. The prediction method, proposed by Prof. Akiyama, is based on energy balance between the total input seismic energy and the energy absorbed by the isolation devices. The method is very accurate. The design methods for devices were developed by authors based on experimental and finite element analysis results.

  9. A SIMPLIFIED WATER QUALITY MODEL FOR WETLANDS

    Institute of Scientific and Technical Information of China (English)

    Jan-Tai KUO; Jihn-Sung LAI; Wu-Seng LUNG; Chou-Ping YANG

    2004-01-01

    The purpose of this study is to develop a simplified mathematical model to simulate suspended solids and total phosphorus concentrations in a wetland or detention pond.Field data collected from a wet detention pond during storms were used to demonstrate the application of this model.Favorable agreements between the model results and data were achieved.The ratio of average outlet method and summary of loads method were used to quantify the removal efficiency of pollutants,reflecting the efficiencies are very close.The results of this study can be used for nonpoint source pollution control,wastewater treatment or best management practices (BMPs) through the wetland.

  10. Simplified analysis for liquid pathway studies

    International Nuclear Information System (INIS)

    The analysis of the potential contamination of surface water via groundwater contamination from severe nuclear accidents is routinely calculated during licensing reviews. This analysis is facilitated by the methods described in this report, which is codified into a BASIC language computer program, SCREENLP. This program performs simplified calculations for groundwater and surface water transport and calculates population doses to potential users for the contaminated water irrespective of possible mitigation methods. The results are then compared to similar analyses performed using data for the generic sites in NUREG-0440, Liquid Pathway Generic Study, to determine if the site being investigated would pose any unusual liquid pathway hazards

  11. Improvement of Test Automation

    OpenAIRE

    Räsänen, Timo

    2013-01-01

    The purpose for this study was to find out how to ensure that the automated testing of MME in the Network Verification will continue smooth and reliable while using the in-house developed test automation framework. The goal of this thesis was to reveal the reasons of the currently challenging situation and to find the key elements to be improved in the MME testing carried by the test automation. Also a reason for the study was to get solutions as to how to change the current procedures and wa...

  12. Chef infrastructure automation cookbook

    CERN Document Server

    Marschall, Matthias

    2013-01-01

    Chef Infrastructure Automation Cookbook contains practical recipes on everything you will need to automate your infrastructure using Chef. The book is packed with illustrated code examples to automate your server and cloud infrastructure.The book first shows you the simplest way to achieve a certain task. Then it explains every step in detail, so that you can build your knowledge about how things work. Eventually, the book shows you additional things to consider for each approach. That way, you can learn step-by-step and build profound knowledge on how to go about your configuration management

  13. Simplified models of mixed dark matter

    International Nuclear Information System (INIS)

    We explore simplified models of mixed dark matter (DM), defined here to be a stable relic composed of a singlet and an electroweak charged state. Our setup describes a broad spectrum of thermal DM candidates that can naturally accommodate the observed DM abundance but are subject to substantial constraints from current and upcoming direct detection experiments. We identify ''blind spots'' at which the DM-Higgs coupling is identically zero, thus nullifying direct detection constraints on spin independent scattering. Furthermore, we characterize the fine-tuning in mixing angles, i.e. well-tempering, required for thermal freeze-out to accommodate the observed abundance. Present and projected limits from LUX and XENON1T force many thermal relic models into blind spot tuning, well-tempering, or both. This simplified model framework generalizes bino-Higgsino DM in the MSSM, singlino-Higgsino DM in the NMSSM, and scalar DM candidates that appear in models of extended Higgs sectors

  14. Simplified models of mixed dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, Clifford; Sanford, David, E-mail: clifford.cheung@caltech.edu, E-mail: dsanford@caltech.edu [California Institute of Technology, Pasadena, CA 91125 (United States)

    2014-02-01

    We explore simplified models of mixed dark matter (DM), defined here to be a stable relic composed of a singlet and an electroweak charged state. Our setup describes a broad spectrum of thermal DM candidates that can naturally accommodate the observed DM abundance but are subject to substantial constraints from current and upcoming direct detection experiments. We identify ''blind spots'' at which the DM-Higgs coupling is identically zero, thus nullifying direct detection constraints on spin independent scattering. Furthermore, we characterize the fine-tuning in mixing angles, i.e. well-tempering, required for thermal freeze-out to accommodate the observed abundance. Present and projected limits from LUX and XENON1T force many thermal relic models into blind spot tuning, well-tempering, or both. This simplified model framework generalizes bino-Higgsino DM in the MSSM, singlino-Higgsino DM in the NMSSM, and scalar DM candidates that appear in models of extended Higgs sectors.

  15. Automated Vehicles Symposium 2014

    CERN Document Server

    Beiker, Sven; Road Vehicle Automation 2

    2015-01-01

    This paper collection is the second volume of the LNMOB series on Road Vehicle Automation. The book contains a comprehensive review of current technical, socio-economic, and legal perspectives written by experts coming from public authorities, companies and universities in the U.S., Europe and Japan. It originates from the Automated Vehicle Symposium 2014, which was jointly organized by the Association for Unmanned Vehicle Systems International (AUVSI) and the Transportation Research Board (TRB) in Burlingame, CA, in July 2014. The contributions discuss the challenges arising from the integration of highly automated and self-driving vehicles into the transportation system, with a focus on human factors and different deployment scenarios. This book is an indispensable source of information for academic researchers, industrial engineers, and policy makers interested in the topic of road vehicle automation.

  16. I-94 Automation FAQs

    Data.gov (United States)

    Department of Homeland Security — In order to increase efficiency, reduce operating costs and streamline the admissions process, U.S. Customs and Border Protection has automated Form I-94 at air and...

  17. Automated Vehicles Symposium 2015

    CERN Document Server

    Beiker, Sven

    2016-01-01

    This edited book comprises papers about the impacts, benefits and challenges of connected and automated cars. It is the third volume of the LNMOB series dealing with Road Vehicle Automation. The book comprises contributions from researchers, industry practitioners and policy makers, covering perspectives from the U.S., Europe and Japan. It is based on the Automated Vehicles Symposium 2015 which was jointly organized by the Association of Unmanned Vehicle Systems International (AUVSI) and the Transportation Research Board (TRB) in Ann Arbor, Michigan, in July 2015. The topical spectrum includes, but is not limited to, public sector activities, human factors, ethical and business aspects, energy and technological perspectives, vehicle systems and transportation infrastructure. This book is an indispensable source of information for academic researchers, industrial engineers and policy makers interested in the topic of road vehicle automation.

  18. Hydrometeorological Automated Data System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Office of Hydrologic Development of the National Weather Service operates HADS, the Hydrometeorological Automated Data System. This data set contains the last...

  19. An automated Certification Authority

    CERN Document Server

    Shamardin, L V

    2002-01-01

    This note describe an approach to building an automated Certification Authority. It is compatible with basic requirements of RFC2527. It also supports Registration Authorities and Globus Toolkit grid-cert-renew automatic certificate renewal.

  20. Disassembly automation automated systems with cognitive abilities

    CERN Document Server

    Vongbunyong, Supachai

    2015-01-01

    This book presents a number of aspects to be considered in the development of disassembly automation, including the mechanical system, vision system and intelligent planner. The implementation of cognitive robotics increases the flexibility and degree of autonomy of the disassembly system. Disassembly, as a step in the treatment of end-of-life products, can allow the recovery of embodied value left within disposed products, as well as the appropriate separation of potentially-hazardous components. In the end-of-life treatment industry, disassembly has largely been limited to manual labor, which is expensive in developed countries. Automation is one possible solution for economic feasibility. The target audience primarily comprises researchers and experts in the field, but the book may also be beneficial for graduate students.

  1. Automated security management

    CERN Document Server

    Al-Shaer, Ehab; Xie, Geoffrey

    2013-01-01

    In this contributed volume, leading international researchers explore configuration modeling and checking, vulnerability and risk assessment, configuration analysis, and diagnostics and discovery. The authors equip readers to understand automated security management systems and techniques that increase overall network assurability and usability. These constantly changing networks defend against cyber attacks by integrating hundreds of security devices such as firewalls, IPSec gateways, IDS/IPS, authentication servers, authorization/RBAC servers, and crypto systems. Automated Security Managemen

  2. Automating Supplier Selection Procedures

    OpenAIRE

    Davidrajuh, Reggie

    2001-01-01

    This dissertation describes a methodology, tools, and implementation techniques of automating supplier selection procedures of a small and medium-sized agile virtual enterprise. Firstly, a modeling approach is devised that can be used to model the supplier selection procedures of an enterprise. This modeling approach divides the supplier selection procedures broadly into three stages, the pre-selection, selection, and post-selection stages. Secondly, a methodology is presented for automating ...

  3. Taiwan Automated Telescope Network

    OpenAIRE

    Shuhrat Ehgamberdiev; Alexander Serebryanskiy; Antonio Jimenez; Li-Han Wang; Ming-Tsung Sun; Javier Fernandez Fernandez; Dean-Yi Chou

    2010-01-01

    A global network of small automated telescopes, the Taiwan Automated Telescope (TAT) network, dedicated to photometric measurements of stellar pulsations, is under construction. Two telescopes have been installed in Teide Observatory, Tenerife, Spain and Maidanak Observatory, Uzbekistan. The third telescope will be installed at Mauna Loa Observatory, Hawaii, USA. Each system uses a 9-cm Maksutov-type telescope. The effective focal length is 225 cm, corresponding to an f-ratio of 25. The field...

  4. Automated Lattice Perturbation Theory

    Energy Technology Data Exchange (ETDEWEB)

    Monahan, Christopher

    2014-11-01

    I review recent developments in automated lattice perturbation theory. Starting with an overview of lattice perturbation theory, I focus on the three automation packages currently "on the market": HiPPy/HPsrc, Pastor and PhySyCAl. I highlight some recent applications of these methods, particularly in B physics. In the final section I briefly discuss the related, but distinct, approach of numerical stochastic perturbation theory.

  5. Automated functional software testing

    OpenAIRE

    Jelnikar, Kristina

    2009-01-01

    The following work describes an approach to software test automation of functional testing. In the introductory part we are introducing what testing problems development companies are facing. The second chapter describes some testing methods, what role does testing have in software development, some approaches to software development and the meaning of testing environment. Chapter 3 is all about test automation. After a brief historical presentation, we are demonstrating through s...

  6. Instant Sikuli test automation

    CERN Document Server

    Lau, Ben

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. A concise guide written in an easy-to follow style using the Starter guide approach.This book is aimed at automation and testing professionals who want to use Sikuli to automate GUI. Some Python programming experience is assumed.

  7. Collective Tuning Initiative: automating and accelerating development and optimization of computing systems

    OpenAIRE

    Fursin, Grigori

    2009-01-01

    International audience Computing systems rarely deliver best possible performance due to ever increasing hardware and software complexity and limitations of the current optimization technology. Additional code and architecture optimizations are often required to improve execution time, size, power consumption, reliability and other important characteristics of computing systems. However, it is often a tedious, repetitive, isolated and time consuming process. In order to automate, simplify ...

  8. Aeroacoustic Analysis of a Simplified Landing Gear

    Science.gov (United States)

    Lockard, David P.; Khorrami, Mehdi, R.; Li, Fei

    2004-01-01

    A hybrid approach is used to investigate the noise generated by a simplified landing gear without small scale parts such as hydraulic lines and fasteners. The Ffowcs Williams and Hawkings equation is used to predict the noise at far-field observer locations from flow data provided by an unsteady computational fluid dynamics calculation. A simulation with 13 million grid points has been completed, and comparisons are made between calculations with different turbulence models. Results indicate that the turbulence model has a profound effect on the levels and character of the unsteadiness. Flow data on solid surfaces and a set of permeable surfaces surrounding the gear have been collected. Noise predictions using the porous surfaces appear to be contaminated by errors caused by large wake fluctuations passing through the surfaces. However, comparisons between predictions using the solid surfaces with the near-field CFD solution are in good agreement giving confidence in the far-field results.

  9. Simplified Model of Nonlinear Landau Damping

    Energy Technology Data Exchange (ETDEWEB)

    N. A. Yampolsky and N. J. Fisch

    2009-07-16

    The nonlinear interaction of a plasma wave with resonant electrons results in a plateau in the electron distribution function close to the phase velocity of the plasma wave. As a result, Landau damping of the plasma wave vanishes and the resonant frequency of the plasma wave downshifts. However, this simple picture is invalid when the external driving force changes the plasma wave fast enough so that the plateau cannot be fully developed. A new model to describe amplification of the plasma wave including the saturation of Landau damping and the nonlinear frequency shift is proposed. The proposed model takes into account the change of the plasma wave amplitude and describes saturation of the Landau damping rate in terms of a single fluid equation, which simplifies the description of the inherently kinetic nature of Landau damping. A proposed fluid model, incorporating these simplifications, is verified numerically using a kinetic Vlasov code.

  10. Michel Henon, a playfull and simplifying mind

    CERN Document Server

    Petit, Jean-Marc

    2014-01-01

    Several chapters in this book present various aspects of Michel Henon's scientific acheivements that spread over a large range of subjects, and yet managed to make deep contributions to most of them. The authors of these chapters make a much better job at demonstrating the big advancements that Michel Henon allowed in these fields than I could ever do. Here I rather present some facets of his personnality that most appealed to me. Michel Henon was a reserved person, almost shy, so it was not obvious for a young student to grasp the profoundness of his insight and what a marvelous advisor he could be. The two most prominent aspects of his mind, in my view, were his ability to simplify any scientific question to its core complexity, and to find the fun and amusing part in his everyday work, even in the tiniest details of his scientific investigations.

  11. A simplified analytical model for pool swell

    International Nuclear Information System (INIS)

    Vapour suppression pool is being used in the containment of PHWR's to limit the pressure and temperature build-up in the containment following a LOCA. The discharge of high pressure water due to LOCA flashes into steam in the drywell, causes a rapid pressure build-up and forces an air-steam mixture into the suppression pool via the vent system. The containment and the pool internal structures need to withstand the hydrodynamic loading due to jet impingement and general motion of the pool water during the water clearing phase from the vents, the loads associated with pool swell in the subsequent air-clearing phase and those due to chugging - the oscillatory condensation of steam - apart from the general thermodynamic loading due to the mass and energy releases from the LOCA. This paper presents a simplified analytical model for pool swell assuming that the bubble is spherical in shape and it migrates vertically. (orig./HP)

  12. An Approach to Simplify Reversible Logic Circuits

    Directory of Open Access Journals (Sweden)

    Pabitra Roy

    2012-09-01

    Full Text Available Energy loss is one of the major problems in traditional irreversible circuits. For every bit of information loss kTln2 joules of heat is lost. In order to reduce the energy loss the concept of reversible logic circuits are introduced. Here we have described an algorithm for simplifying the reversible logic circuit and hence reduction of circuit cost and energy. The algorithm considers sub_circuit with respect to their number of lines and contiguous gates. The resulting sub_circuits are re-synthesized with smaller equivalent implementation. The process continues until circuit cost reaches good enough for Application or until a given computation budget has been exhausted. The circuit is constructed by NOT, CNOT and Toffoli gates only. By applying the algorithm and using the equivalent implementation we will get significant reduction of circuit cost and hence energy.

  13. Combustion Safety Simplified Test Protocol Field Study

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L. [Gas Technology Inst., Des Plaines, IL (United States); Cautley, D. [Gas Technology Inst., Des Plaines, IL (United States); Bohac, D. [Gas Technology Inst., Des Plaines, IL (United States); Francisco, P. [Gas Technology Inst., Des Plaines, IL (United States); Shen, L. [Gas Technology Inst., Des Plaines, IL (United States); Gloss, S. [Gas Technology Inst., Des Plaines, IL (United States)

    2015-11-01

    Combustions safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives. A survey of state weatherization agencies on combustion safety issues, details of a field data collection instrumentation package, summary of data collected over seven months, data analysis and results are included. The project team collected field data on 11 houses in 2015.

  14. Simplifying the circuit of Josephson parametric converters

    Science.gov (United States)

    Abdo, Baleegh; Brink, Markus; Chavez-Garcia, Jose; Keefe, George

    Josephson parametric converters (JPCs) are quantum-limited three-wave mixing devices that can play various important roles in quantum information processing in the microwave domain, including amplification of quantum signals, transduction of quantum information, remote entanglement of qubits, nonreciprocal amplification, and circulation of signals. However, the input-output and biasing circuit of a state-of-the-art JPC consists of bulky components, i.e. two commercial off-chip broadband 180-degree hybrids, four phase-matched short coax cables, and one superconducting magnetic coil. Such bulky hardware significantly hinders the integration of JPCs in scalable quantum computing architectures. In my talk, I will present ideas on how to simplify the JPC circuit and show preliminary experimental results

  15. Simplified fundamental force and mass measurements

    Science.gov (United States)

    Robinson, I. A.

    2016-08-01

    The watt balance relates force or mass to the Planck constant h, the metre and the second. It enables the forthcoming redefinition of the unit of mass within the SI by measuring the Planck constant in terms of mass, length and time with an uncertainty of better than 2 parts in 108. To achieve this, existing watt balances require complex and time-consuming alignment adjustments limiting their use to a few national metrology laboratories. This paper describes a simplified construction and operating principle for a watt balance which eliminates the need for the majority of these adjustments and is readily scalable using either electromagnetic or electrostatic actuators. It is hoped that this will encourage the more widespread use of the technique for a wide range of measurements of force or mass. For example: thrust measurements for space applications which would require only measurements of electrical quantities and velocity/displacement.

  16. Analytic solution of simplified Cardan's shaft model

    Directory of Open Access Journals (Sweden)

    Zajíček M.

    2014-12-01

    Full Text Available Torsional oscillations and stability assessment of the homokinetic Cardan shaft with a small misalignment angle is described in this paper. The simplified mathematical model of this system leads to the linearized equation of the Mathieu's type. This equation with and without a stationary damping parameter is considered. The solution of the original differential equation is identical with those one of the Fredholm’s integral equation with degenerated kernel assembled by means of a periodic Green's function. The conditions of solvability of such problem enable the identification of the borders between stability and instability regions. These results are presented in the form of stability charts and they are verified using the Floquet theory. The correctness of oscillation results for the system with periodic stiffness is then validated by means of the Runge-Kutta integration method.

  17. A Simplified Database-Oriented Web Framework

    Institute of Scientific and Technical Information of China (English)

    ZHU Qiao-ming; ZHAO Lei; QIAN Pei-de

    2004-01-01

    The paper firstly analyses disadvantages in the traditional Web database systems.And then it puts forward a simplified framework called database-oriented Web framework (DOWF).In this framework, the pages and the data are all managed by database system.In order to get keywords or search a special page, which the users accessed before, users access the static pages by common script procedure (CSP), and access the dynamic pages by functional script procedure (FSP) and CSP.The article expounds the method how to implement DOWF in details.The paper also analyses the mechanism of a DOWF site by implementing a prototype system.At last, the article gives the features of DOWS in search, in security, in reuse of pages and in offline waiting, etc.

  18. Experimental study on a simplified crossflow turbine

    Directory of Open Access Journals (Sweden)

    Chiyembekezo S. Kaunda, Cuthbert Z. Kimambo, Torbjorn K. Nielsen

    2014-01-01

    Full Text Available The main aim of the study is to enhance the design of a Crossflow turbine, as an appropriate technology for small-scale power generation. This study evaluates the performance of a simplified Crossflow turbine at conditions other than the ‘best efficiency point’. It also explores the ‘reaction’ behavior of the Crossflow turbine as well as characterizes the torque transfer in the two stages of the turbine. The experiments were conducted on a physical simplified Crossflow turbine model using the test facilities in the Waterpower Laboratory at the Norwegian University of Science and Technology. The results show that the maximum turbine efficiency is 79%, achieved at a head of 5m and reduced speed of 13.4; making it a low speed turbine. This turbine efficiency compares well with some reported efficiency values. The result also show that the turbine is efficient when it operates with a degree of reaction and this is achieved at large valve openings; validating observations that the Crossflow turbine is not a pure impulse turbine. Performance evaluation outside the best efficiency point shows that the efficiency decreases with increase in head above the best efficiency head. The turbine efficiency is not sensitive to flow variations: except at a head of 3m, at all tested heads, 25% of the flow at best efficiency point still generates efficiency of above 50%. Torque characterization shows that the second stage plays a significant role in torque transfer, especially when at large valve openings. Therefore, design efforts must also look at how the flow inside the runner interior space can be controlled so that the jet enters the second stage with optimum flow angles. The use of strain gauge to characterize the torque produced using momentum principle as employed in this study presents an additional opportunity to analyze the trends in the torque transfer.

  19. Developing a simplified consent form for biobanking.

    Directory of Open Access Journals (Sweden)

    Laura M Beskow

    Full Text Available BACKGROUND: Consent forms have lengthened over time and become harder for participants to understand. We sought to demonstrate the feasibility of creating a simplified consent form for biobanking that comprises the minimum information necessary to meet ethical and regulatory requirements. We then gathered preliminary data concerning its content from hypothetical biobank participants. METHODOLOGY/PRINCIPAL FINDINGS: We followed basic principles of plain-language writing and incorporated into a 2-page form (not including the signature page those elements of information required by federal regulations and recommended by best practice guidelines for biobanking. We then recruited diabetes patients from community-based practices and randomized half (n = 56 to read the 2-page form, first on paper and then a second time on a tablet computer. Participants were encouraged to use "More information" buttons on the electronic version whenever they had questions or desired further information. These buttons led to a series of "Frequently Asked Questions" (FAQs that contained additional detailed information. Participants were asked to identify specific sentences in the FAQs they thought would be important if they were considering taking part in a biorepository. On average, participants identified 7 FAQ sentences as important (mean 6.6, SD 14.7, range: 0-71. No one sentence was highlighted by a majority of participants; further, 34 (60.7% participants did not highlight any FAQ sentences. CONCLUSIONS: Our preliminary findings suggest that our 2-page form contains the information that most prospective participants identify as important. Combining simplified forms with supplemental material for those participants who desire more information could help minimize consent form length and complexity, allowing the most substantively material information to be better highlighted and enabling potential participants to read the form and ask questions more effectively.

  20. Miniaturized photoelectric angular sensor with simplified design

    Science.gov (United States)

    Dumbravescu, Niculae; Schiaua, Silviu

    1999-09-01

    In building the movable elements of robots, peripheral devices and measuring apparata, increasing the resolution of the angular sensor systems, based on incremental rotary encoders, is essential, together with decreasing the complexity, dimensions and weight. Especially when the angular sensor is integrated in a measuring system, belonging to a programmed light airplane for surveillance, the key issue is to reduce both dimensions and weight. This can be done using a simplified design, which consists in the following solutions: replacement of the fragile Cr on glass substrate, 1.5 mm thick (normally used for the fabrication of incremental disks), with light Cr on polycarbonate substrate, with only 0.15 mm thick; the absence of collimating optics (based on microlenses, used in IR emitter-photocell receiver assembly), as a result of the good coupling efficiency (due to the possible approaching of these elements at minimum 0.45 mm); the shrinkage of the disk's diameters to only 14 mm; the use of surface mounting devices and the related surface mounting technology, enabling to reduce dimensions and weight. The maximum number of slits on a 14 mm diameter dividing disk, usually obtained in a Cr on polycarbonate version, being approx. 1000, no problem occurs in our case, for 360 slits. The requested angular resolution (only 0.5 degrees for the light airplane), using the whole classical '4x digital multiplication' is not necessary, but a lower one of only 2x, resulting in a simplified electronics. The proposed design permitted, that an original arrangement, for building a small size, lightweight, heavy-duty incremental transducer based angular sensor system, to be obtained, useful not only in avionics, but also in robotics, or other special applications. Besides, extending the number of fixed gratings (masks) allows, that many primary signals to be derived, and a further increase in resolution of even 6 angular minutes to be obtained from the initial 360 slits.

  1. The Effect of Information Analysis Automation Display Content on Human Judgment Performance in Noisy Environments

    Science.gov (United States)

    Bass, Ellen J.; Baumgart, Leigh A.; Shepley, Kathryn Klein

    2014-01-01

    Displaying both the strategy that information analysis automation employs to makes its judgments and variability in the task environment may improve human judgment performance, especially in cases where this variability impacts the judgment performance of the information analysis automation. This work investigated the contribution of providing either information analysis automation strategy information, task environment information, or both, on human judgment performance in a domain where noisy sensor data are used by both the human and the information analysis automation to make judgments. In a simplified air traffic conflict prediction experiment, 32 participants made probability of horizontal conflict judgments under different display content conditions. After being exposed to the information analysis automation, judgment achievement significantly improved for all participants as compared to judgments without any of the automation's information. Participants provided with additional display content pertaining to cue variability in the task environment had significantly higher aided judgment achievement compared to those provided with only the automation's judgment of a probability of conflict. When designing information analysis automation for environments where the automation's judgment achievement is impacted by noisy environmental data, it may be beneficial to show additional task environment information to the human judge in order to improve judgment performance. PMID:24847184

  2. 基于体素的形态测量学在阿尔茨海默病及轻度认知功能障碍研究中的应用%Voxel-based Morphometry's Application in Studies of Alzheimer's Disease and Mild Cognition Impairment

    Institute of Scientific and Technical Information of China (English)

    郭艳娥; 张熙; 周波; 王盼; 尚延昌

    2014-01-01

    阿尔茨海默病(Alzheimer's disease,AD)是发生于老年和老年前期、以进行性认知功能障碍和行为异常为特征的中枢神经系统退行性疾病,是老年痴呆中最常见类型.轻度认知功能障碍(mild cognitive impairment,MCI)是介于正常衰老和痴呆之间的一种中间状态,指有轻度的记忆或认知损伤,但尚未达到痴呆程度的一种状态,日常生活和社会功能不受影响,其中很大一部分患者最终进展为AD.临床诊断AD患者多已达中晚期,为了能早期诊断AD及预测MCI的转归,有关AD的生物学标注物的研究成为近年来的科研热点.AD患者颅脑的大体病理特征为脑萎缩,其萎缩有别于正常老龄化所致的退行性改变,有其自身特点,这种特定形式的萎缩有可能成为AD早期诊断的生物学标志物.基于体素的形态测量学(voxel-based morphometry,VBM)是一种基于像素水平对脑核磁图像进行自动、全面、客观分析的技术,可以定量分析全脑结构、刻画出局部脑区结构特征,是一种较好的脑形态分析工具,广泛用于阿尔茨海默病及轻度认知功能障碍的研究中,本文综述了近年来其研究进展,期望为临床及科研提供参考.

  3. 偏执型精神分裂症和双相情感障碍躁狂患者脑灰质体积的比较分析%A Comparative Study of Voxel-based Morphometry in Patients with Paranoid Schizophrenia and Bipolar Mania

    Institute of Scientific and Technical Information of China (English)

    崔立谦; 邓伟; 蒋莉君; 黄朝华; 陈壮飞; 李名立; 龚启勇; 李涛

    2010-01-01

    目的 采用优化的基于体素的形态学(voxel based morphometry,VBM)方法,比较偏执型精神分裂症、双相情感障碍躁狂患者脑灰质体积的差异.方法 运用3.0T磁共振扫描仪对符合美国精神障碍诊断统计手册第4版(DSM-Ⅳ)诊断标准的20例偏执型精神分裂症住院患者、20例双相情感障碍躁狂相住院患者和20例正常对照进行3D T1像扫描.在SPM2平台上,以优化的VBM方法 对高分辨T1加权图像进行处理,比较上述研究对象脑灰质体积的差异.结果 与正常对照比较,偏执型精神分裂症患者右侧颞中回、颞下回,左侧颞上回灰质体积减少,而双侧额下回、双侧屏状核灰质体积增加.双相情感障碍躁狂患者与正常对照比较出现灰质体积减少的脑区包括双侧尾状核,右侧颞叶颞上、中、下回,灰质体积增加的脑区包括左侧顶叶中央后回、双侧楔前叶、右侧额上回、左侧扣带回.偏执型精神分裂症患者与双相情感障碍躁狂患者相比左侧颞上回、左侧额下回、右侧尾状核体灰质体积增加.结论 偏执型精神分裂症患者与双相情感障碍躁狂患者既存在不同脑区的灰质体积的改变,也存在共同的右侧颞叶灰质体积改变.

  4. Automated diagnoses of attention deficit hyperactive disorder using magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Ani eEloyan

    2012-08-01

    Full Text Available Successful automated diagnoses of attention deficit hyperactive disorder (ADHD using imaging and functional biomarkers would have fundamental consequences on the public health impact of the disease. In this work, we show results on the predictability of ADHD using imaging biomarkers and discuss the scientific and diagnostic impacts of the research. We created a prediction model using the landmark ADHD 200 data set focusing on resting state functional connectivity (rs-fc and structural brain imaging. We predicted ADHD status and subtype, obtained by behavioral examination, using imaging data, intelligence quotients and other covariates. The novel contributions of this manuscript include a thorough exploration of prediction and image feature extraction methodology on this form of data, including the use of singular value decompositions, CUR decompositions, random forest, gradient boosting, bagging, voxel-based morphometry and support vector machines as well as important insights into the value, and potentially lack thereof, of imaging biomarkers of disease. The key results include the CUR-based decomposition of the rs-fc-fMRI along with gradient boosting and the prediction algorithm based on a motor network parcellation and random forest algorithm. We conjecture that the CUR decomposition is largely diagnosing common population directions of head motion. Of note, a byproduct of this research is a potential automated method for detecting subtle in-scanner motion. The final prediction algorithm, a weighted combination of several algorithms, had an external test set specificity of 94% with sensitivity of 21%. The most promising imaging biomarker was a correlation graph from a motor network parcellation. In summary, we have undertaken a large-scale statistical exploratory prediction exercise on the unique ADHD 200 data set. The exercise produced several potential leads for future scientific exploration of the neurological basis of ADHD.

  5. Automated Camera Calibration

    Science.gov (United States)

    Chen, Siqi; Cheng, Yang; Willson, Reg

    2006-01-01

    Automated Camera Calibration (ACAL) is a computer program that automates the generation of calibration data for camera models used in machine vision systems. Machine vision camera models describe the mapping between points in three-dimensional (3D) space in front of the camera and the corresponding points in two-dimensional (2D) space in the camera s image. Calibrating a camera model requires a set of calibration data containing known 3D-to-2D point correspondences for the given camera system. Generating calibration data typically involves taking images of a calibration target where the 3D locations of the target s fiducial marks are known, and then measuring the 2D locations of the fiducial marks in the images. ACAL automates the analysis of calibration target images and greatly speeds the overall calibration process.

  6. Automated telescope scheduling

    Science.gov (United States)

    Johnston, Mark D.

    1988-08-01

    With the ever increasing level of automation of astronomical telescopes the benefits and feasibility of automated planning and scheduling are becoming more apparent. Improved efficiency and increased overall telescope utilization are the most obvious goals. Automated scheduling at some level has been done for several satellite observatories, but the requirements on these systems were much less stringent than on modern ground or satellite observatories. The scheduling problem is particularly acute for Hubble Space Telescope: virtually all observations must be planned in excruciating detail weeks to months in advance. Space Telescope Science Institute has recently made significant progress on the scheduling problem by exploiting state-of-the-art artificial intelligence software technology. What is especially interesting is that this effort has already yielded software that is well suited to scheduling groundbased telescopes, including the problem of optimizing the coordinated scheduling of more than one telescope.

  7. The simplified material parameter equation for elliptical cylinder cloaks

    Institute of Scientific and Technical Information of China (English)

    Ma Hua; Qu Shao-Bo; Xu Zhuo; Zhang Jie-Qiu; Wang Jia-Fu

    2009-01-01

    We simplify the material parameter equation for elliptical cylinder cloaks under transverse-electric and transverse-magnetic modcis, respectively, and confirm these simplified equations by numerical simulations. As a result, the number of the component parameters is reduced from three to two, which simplifies the design of meta-materials and thus opens up the possibility of achieving elliptical cylinder cloaks in an easy way.

  8. Simplified Modeling of Oxidation of Hydrocarbons

    Science.gov (United States)

    Bellan, Josette; Harstad, Kenneth

    2008-01-01

    A method of simplified computational modeling of oxidation of hydrocarbons is undergoing development. This is one of several developments needed to enable accurate computational simulation of turbulent, chemically reacting flows. At present, accurate computational simulation of such flows is difficult or impossible in most cases because (1) the numbers of grid points needed for adequate spatial resolution of turbulent flows in realistically complex geometries are beyond the capabilities of typical supercomputers now in use and (2) the combustion of typical hydrocarbons proceeds through decomposition into hundreds of molecular species interacting through thousands of reactions. Hence, the combination of detailed reaction- rate models with the fundamental flow equations yields flow models that are computationally prohibitive. Hence, further, a reduction of at least an order of magnitude in the dimension of reaction kinetics is one of the prerequisites for feasibility of computational simulation of turbulent, chemically reacting flows. In the present method of simplified modeling, all molecular species involved in the oxidation of hydrocarbons are classified as either light or heavy; heavy molecules are those having 3 or more carbon atoms. The light molecules are not subject to meaningful decomposition, and the heavy molecules are considered to decompose into only 13 specified constituent radicals, a few of which are listed in the table. One constructs a reduced-order model, suitable for use in estimating the release of heat and the evolution of temperature in combustion, from a base comprising the 13 constituent radicals plus a total of 26 other species that include the light molecules and related light free radicals. Then rather than following all possible species through their reaction coordinates, one follows only the reduced set of reaction coordinates of the base. The behavior of the base was examined in test computational simulations of the combustion of

  9. Simplified Model of Brushless Synchronous Generator for Real Time Simulation

    CERN Document Server

    Lopez, M D; Rebollo, E; Blanquez, F R

    2015-01-01

    This paper presents a simplified model of brushless synchronous machine for saving hardware resources in a real time simulation system. Firstly, a brushless excitation system model is described. Thereafter, the simplified transfer function of an AC exciter and rotating diodes of the brushless excitation system is estimated. Finally, the complete system is simulated, comparing the main generator's voltage with both detailed and simplified excitation systems in several scenarios. These results show the accuracy of the simplified model against the detailed simulation model, resulting on an important hardware resources savings.

  10. Myths in test automation

    OpenAIRE

    Jazmine Francis

    2015-01-01

    Myths in automation of software testing is an issue of discussion that echoes about the areas of service in validation of software industry. Probably, the first though that appears in knowledgeable reader would be Why this old topic again? What's New to discuss the matter? But, for the first time everyone agrees that undoubtedly automation testing today is not today what it used to be ten or fifteen years ago, because it has evolved in scope and magnitude. What began as a simple linear script...

  11. Automated phantom assay system

    International Nuclear Information System (INIS)

    This paper describes an automated phantom assay system developed for assaying phantoms spiked with minute quantities of radionuclides. The system includes a computer-controlled linear-translation table that positions the phantom at exact distances from a spectrometer. A multichannel analyzer (MCA) interfaces with a computer to collect gamma spectral data. Signals transmitted between the controller and MCA synchronize data collection and phantom positioning. Measured data are then stored on disk for subsequent analysis. The automated system allows continuous unattended operation and ensures reproducible results

  12. 轻度认知损害和阿尔茨海默病的大脑灰质体积及其与记忆功能的关系%Relationship between the brain gray matter volume and memory performance in mild cognitive impairment and Alzheimer' s disease: a voxel-based morphometric study

    Institute of Scientific and Technical Information of China (English)

    何毅; 王华丽; 苏敏莹; 袁慧书; 李涛; 张美燕; 于欣

    2012-01-01

    Objective To explore the relationship between the gray matter loss measured with voxel-based morphometry (VBM) and memory performance in mild cognitive impairment (MCI) and Alzheimer's disease (AD). Methods Eighty-six subjects were recruited, including 56 patients with mild AD, 14 subjects with MCI, and 16 healthy controls. All subjects were administered the comprehensive memory tests, All 3D T1 images were analyzed by using the procedures of optimized VBM analysis. Results Compared to control group, memory performance were significantly worse in AD and MCI groups, in a pattern of AD < MCI < control. Gray matter loss was detected extensively in the temporal, frontal and parietal lobes in AD group. There was More severe atrophy in frontal and parietal lobes in AD compared to MCI group. In AD group, the 3D statistical maps showed extensive cortical areas in the temporal, frontal and parietal lobes were linked to immediate object memory performance. Score of 30-min delayed recall of objects was correlated strongly with the gray matter density in the bilateral superior frontal gyri, thalamus, right anterior cingulate, medial frontal gyri, middle temporal gyri, and paracentral lobule (P < 0.01). Composite memory score was closely correlated with the gray matter density in the left parahippocampal gyrus, middle temporal gyri, precuneus, superior frontal gyri, middle frontal gyri, cingulate gyrus, and right parahippocampal gyrus, medial frontal gyri, and inferior frontal gyri (P < 0.01). In MCI and NC groups, suprathreshold clusters were not correlated with the memory scores. Conclusion Memory impairment is strongly correlated with extensive cerebral atrophy in AD. Brain volume in MCI individuals are not significantly correlated with memory performance, suggesting that memory impairment, an early sign of MCI, may not be directly attributable to brain atrophy. Further investigations on microstructural or functional connectivity are warranted.%目的

  13. 2D DIGITAL SIMPLIFIED FLOW VALVE

    Institute of Scientific and Technical Information of China (English)

    Ruan Jian; Li Sheng; Pei Xiang; Burton R; Ukrainetz P; Bitner D

    2004-01-01

    The 2D digital simplified flow valve is composed of a pilot-operated valve designed with both rotary and linear motions of a single spool,and a stepper motor under continual control.How the structural parameters affect the static and dynamic characteristics of the valve is first clarified and a criterion for stability is presented.Experiments are designed to test the performance of the valve.It is necessary to establish a balance between the static and dynamic characteristics in deciding the structural parameters.Nevertheless,it is possible to maintain the dynamic response at a fairly high level,while keeping the leakage of the pilot stage at an acceptable level.One of the features of the digital valve is stage control.In stage control the nonlinearities,such as electromagnetic saturation and hysteresis,are greatly reduced.To a large extent the dynamic response of the valve is decided by the executing cycle of the control algorithm.

  14. Simplified environmental study on innovative bridge structure.

    Science.gov (United States)

    Bouhaya, Lina; Le Roy, Robert; Feraille-Fresnet, Adélaïde

    2009-03-15

    The aim of this paper is to present a simplified life cycle assessment on an innovative bridge structure, made of wood and ultra high performance concrete, which combines mechanical performance with minimum environmental impact. The environmental analysis was conducted from cradle to grave using the Life Cycle Assessment method. It was restricted to energy release and greenhouse gas emissions. Assumptions are detailed for each step of the analysis. For the wood end-of-life, three scenarios were proposed: dumping, burning, and recycling. Results show that the most energy needed is in the production phase, which represents 73.4% of the total amount. Analysis shows that the renewable energy is about 70% of the production energy. Wood, through its biomass CO2, contributes positively to the environmental impact. It was concluded that no scenario can be the winner on both impacts. Indeed, the end-of-life wood recycling gives the best impact on CO2 release, whereas burning wood, despite its remarkable energy impact is the worst. According to the emphasis given to each impact, designers will be able to choose one or the other. PMID:19368215

  15. Simplified Optics and Controls for Laser Communications

    Science.gov (United States)

    Chen, Chien-Chung; Hemmati, Hamid

    2006-01-01

    A document discusses an architecture of a spaceborne laser communication system that provides for a simplified control subsystem that stabilizes the line of sight in a desired direction. Heretofore, a typical design for a spaceborne laser communication system has called for a high-bandwidth control loop, a steering mirror and associated optics, and a fast steering-mirror actuator to stabilize the line of sight in the presence of vibrations. In the present architecture, the need for this fast steering-mirror subsystem is eliminated by mounting the laser-communication optics on a disturbance-free platform (DFP) that suppresses coupling of vibrations to the optics by 60 dB. Taking advantage of microgravitation, in the DFP, the optical assembly is free-flying relative to the rest of the spacecraft, and a low-spring-constant pointing control subsystem exerts small forces to regulate the position and orientation of the optics via voice coils. All steering is effected via the DFP, which can be controlled in all six degrees of freedom relative to the spacecraft. A second control loop, closed around a position sensor and the spacecraft attitude-control system, moves the spacecraft as needed to prevent mechanical contact with the optical assembly.

  16. Combustion Safety Simplified Test Protocol Field Study

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L [Gas Technology Inst., Des Plaines, IL (United States); Cautley, D. [Gas Technology Inst., Des Plaines, IL (United States); Bohac, D. [Gas Technology Inst., Des Plaines, IL (United States); Francisco, P. [Gas Technology Inst., Des Plaines, IL (United States); Shen, L. [Gas Technology Inst., Des Plaines, IL (United States); Gloss, S. [Gas Technology Inst., Des Plaines, IL (United States)

    2015-11-05

    "9Combustions safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives. A survey of state weatherization agencies on combustion safety issues, details of a field data collection instrumentation package, summary of data collected over seven months, data analysis and results are included. The project provides several key results. State weatherization agencies do not generally track combustion safety failures, the data from those that do suggest that there is little actual evidence that combustion safety failures due to spillage from non-dryer exhaust are common and that only a very small number of homes are subject to the failures. The project team collected field data on 11 houses in 2015. Of these homes, two houses that demonstrated prolonged and excessive spillage were also the only two with venting systems out of compliance with the National Fuel Gas Code. The remaining homes experienced spillage that only occasionally extended beyond the first minute of operation. Combustion zone depressurization, outdoor temperature, and operation of individual fans all provide statistically significant predictors of spillage.

  17. Interferometric phase reconstruction using simplified coherence network

    Science.gov (United States)

    Zhang, Kui; Song, Ruiqing; Wang, Hui; Wu, Di; Wang, Hua

    2016-09-01

    Interferometric time-series analysis techniques, which extend the traditional differential radar interferometry, have demonstrated a strong capability for monitoring ground surface displacement. Such techniques are able to obtain the temporal evolution of ground deformation within millimeter accuracy by using a stack of synthetic aperture radar (SAR) images. In order to minimize decorrelation between stacked SAR images, the phase reconstruction technique has been developed recently. The main idea of this technique is to reform phase observations along a SAR stack by taking advantage of a maximum likelihood estimator which is defined on the coherence matrix estimated from each target. However, the phase value of a coherence matrix element might be considerably biased when its corresponding coherence is low. In this case, it will turn to an outlying sample affecting the corresponding phase reconstruction process. In order to avoid this problem, a new approach is developed in this paper. This approach considers a coherence matrix element to be an arc in a network. A so-called simplified coherence network (SCN) is constructed to decrease the negative impact of outlying samples. Moreover, a pointed iterative strategy is designed to resolve the transformed phase reconstruction problem defined on a SCN. For validation purposes, the proposed method is applied to 29 real SAR images. The results demonstrate that the proposed method has an excellent computational efficiency and could obtain more reliable phase reconstruction solutions compared to the traditional method using phase triangulation algorithm.

  18. Face Recognition Using Simplified Fuzzy Artmap

    Directory of Open Access Journals (Sweden)

    Antu Annam Thomas

    2011-02-01

    Full Text Available Face recognition has become one of the most active research areas of pattern recognition since the early1990s. This project thesis proposes a novel face recognition method based on Simplified Fuzzy ARTMAP(SFAM. For extracting features to be used for classification, combination of Principal ComponentAnalysis (PCA and Linear Discriminant Analysis (LDA is used. This is for improving the capability ofLDA and PCA when used alone.PCA reduces the dimensionality of input face images while LDA extractsthe features that help the classifier to classify the input face images. The classifier employed was SFAM.Experiment is conducted on ORL, Yale and Indian Face Database and results demonstrate SFAM’sefficiency as a recognizer. The training time of SFAM is negligible. SFAM has the added advantage thatthe network is adaptive, that is, during testing phase if the network comes across a new face that it is nottrained for; the network identifies this to be a new face and also learns this new face. Thus SFAM can beused in applications where database needs to be updated frequently. SFAM thus proves itself to be anefficient recognizer when a speedy, accurate and adaptive Face Recognition System is required.

  19. Simplified Dynamic Analysis of Grinders Spindle Node

    Science.gov (United States)

    Demec, Peter

    2014-12-01

    The contribution deals with the simplified dynamic analysis of surface grinding machine spindle node. Dynamic analysis is based on the use of the transfer matrix method, which is essentially a matrix form of method of initial parameters. The advantage of the described method, despite the seemingly complex mathematical apparatus, is primarily, that it does not require for solve the problem of costly commercial software using finite element method. All calculations can be made for example in MS Excel, which is advantageous especially in the initial stages of constructing of spindle node for the rapid assessment of the suitability its design. After detailing the entire structure of spindle node is then also necessary to perform the refined dynamic analysis in the environment of FEM, which it requires the necessary skills and experience and it is therefore economically difficult. This work was developed within grant project KEGA No. 023TUKE-4/2012 Creation of a comprehensive educational - teaching material for the article Production technique using a combination of traditional and modern information technology and e-learning.

  20. Simplified probabilistic risk assessment in fuel reprocessing

    International Nuclear Information System (INIS)

    An evaluation was made to determine if a backup mass tracking computer would significantly reduce the probability of criticality in the fuel reprocessing of the Integral Fast Reactor. Often tradeoff studies, such as this, must be made that would greatly benefit from a Probably Risk Assessment (PRA). The major benefits of a complete PRA can often be accrued with a Simplified Probabilistic Risk Assessment (SPRA). An SPRA was performed by selecting a representative fuel reprocessing operation (moving a piece of fuel) for analysis. It showed that the benefit of adding parallel computers was small compared to the benefit which could be obtained by adding parallelism to two computer input steps and two of the weighing operations. The probability of an incorrect material moves with the basic process is estimated to be 4 out of 100 moves. The actual values of the probability numbers are considered accurate to within an order of magnitude. The most useful result of developing the fault trees accrue from the ability to determine where significant improvements in the process can be made. By including the above mentioned parallelism, the error move rate can be reduced to 1 out of 1000

  1. MDSplus automated build and distribution system

    International Nuclear Information System (INIS)

    Support of the MDSplus data handling system has been enhanced by the addition of an automated build system which does nightly builds of MDSplus for many computer platforms producing software packages which can now be downloaded using a web browser or via package repositories suitable for automatic updating. The build system was implemented using an extensible continuous integration server product called Hudson which schedules software builds on a collection of VMware based virtual machines. New releases are created based on updates via the MDSplus cvs code repository and versioning are managed using cvs tags and branches. Currently stable, beta and alpha releases of MDSplus are maintained for eleven different platforms including Windows, MacOSX, RedHat Enterprise Linux, Fedora, Ubuntu and Solaris. For some of these platforms, MDSplus packaging has been broken into functional modules so users can pick and choose which MDSplus features they want to install. An added feature to the latest Linux based platforms is the use of package dependencies. When installing MDSplus from the package repositories, any additional required packages used by MDSplus will be installed automatically greatly simplifying the installation of MDSplus. This paper will describe the MDSplus package automated build and distribution system

  2. A spectrum of applications of automated reasoning

    International Nuclear Information System (INIS)

    The likelihood of an automated reasoning program being of substantial assistance for a wide spectrum of applications rests with the nature of the options and parameters it offers on which to base needed strategies and methodologies. This article focuses on such a spectrum, featuring W. McCune's program OTTER, discussing widely varied successes in answering open questions, and touching on some of the strategies and methodologies that played a key role. The applications include finding a first proof, discovering single axioms, locating improved axiom systems, and simplifying existing proofs. The last application is directly pertinent to the recently found (by R. Thiele) Hilbert's twenty-fourth problem-which is extremely amenable to attack with the appropriate automated reasoning program, a problem concerned with proof simplification. The methodologies include those for seeking shorter proofs and for finding proofs that avoid unwanted lemmas or classes of term, a specific option for seeking proofs with smaller equational or formula complexity, and a different option to address the variable richness of a proof. The type of proof one obtains with the use of OTTER is Hilbert-style axiomatic, including details that permit one sometimes to gain new insights. We include questions still open and challenges that merit consideration

  3. Automated conflict resolution issues

    Science.gov (United States)

    Wike, Jeffrey S.

    1991-01-01

    A discussion is presented of how conflicts for Space Network resources should be resolved in the ATDRSS era. The following topics are presented: a description of how resource conflicts are currently resolved; a description of issues associated with automated conflict resolution; present conflict resolution strategies; and topics for further discussion.

  4. Protokoller til Home Automation

    DEFF Research Database (Denmark)

    Kjær, Kristian Ellebæk

    2008-01-01

    computer, der kan skifte mellem foruddefinerede indstillinger. Nogle gange kan computeren fjernstyres over internettet, så man kan se hjemmets status fra en computer eller måske endda fra en mobiltelefon. Mens nævnte anvendelser er klassiske indenfor home automation, er yderligere funktionalitet dukket op...

  5. Myths in test automation

    Directory of Open Access Journals (Sweden)

    Jazmine Francis

    2015-01-01

    Full Text Available Myths in automation of software testing is an issue of discussion that echoes about the areas of service in validation of software industry. Probably, the first though that appears in knowledgeable reader would be Why this old topic again? What's New to discuss the matter? But, for the first time everyone agrees that undoubtedly automation testing today is not today what it used to be ten or fifteen years ago, because it has evolved in scope and magnitude. What began as a simple linear scripts for web applications today has a complex architecture and a hybrid framework to facilitate the implementation of testing applications developed with various platforms and technologies. Undoubtedly automation has advanced, but so did the myths associated with it. The change in perspective and knowledge of people on automation has altered the terrain. This article reflects the points of views and experience of the author in what has to do with the transformation of the original myths in new versions, and how they are derived; also provides his thoughts on the new generation of myths.

  6. Automated data model evaluation

    International Nuclear Information System (INIS)

    Modeling process is essential phase within information systems development and implementation. This paper presents methods and techniques for analysis and evaluation of data model correctness. Recent methodologies and development results regarding automation of the process of model correctness analysis and relations with ontology tools has been presented. Key words: Database modeling, Data model correctness, Evaluation

  7. Automated solvent concentrator

    Science.gov (United States)

    Griffith, J. S.; Stuart, J. L.

    1976-01-01

    Designed for automated drug identification system (AUDRI), device increases concentration by 100. Sample is first filtered, removing particulate contaminants and reducing water content of sample. Sample is extracted from filtered residue by specific solvent. Concentrator provides input material to analysis subsystem.

  8. ELECTROPNEUMATIC AUTOMATION EDUCATIONAL LABORATORY

    OpenAIRE

    Dolgorukov, S. O.; National Aviation University; Roman, B. V.; National Aviation University

    2013-01-01

    The article reflects current situation in education regarding mechatronics learning difficulties. Com-plex of laboratory test benches on electropneumatic automation are considered as a tool in advancing through technical science. Course of laboratory works developed to meet the requirement of efficient and reliable way of practical skills acquisition is regarded the simplest way for students to learn the ba-sics of mechatronics.

  9. Automating spectral measurements

    Science.gov (United States)

    Goldstein, Fred T.

    2008-09-01

    This paper discusses the architecture of software utilized in spectroscopic measurements. As optical coatings become more sophisticated, there is mounting need to automate data acquisition (DAQ) from spectrophotometers. Such need is exacerbated when 100% inspection is required, ancillary devices are utilized, cost reduction is crucial, or security is vital. While instrument manufacturers normally provide point-and-click DAQ software, an application programming interface (API) may be missing. In such cases automation is impossible or expensive. An API is typically provided in libraries (*.dll, *.ocx) which may be embedded in user-developed applications. Users can thereby implement DAQ automation in several Windows languages. Another possibility, developed by FTG as an alternative to instrument manufacturers' software, is the ActiveX application (*.exe). ActiveX, a component of many Windows applications, provides means for programming and interoperability. This architecture permits a point-and-click program to act as automation client and server. Excel, for example, can control and be controlled by DAQ applications. Most importantly, ActiveX permits ancillary devices such as barcode readers and XY-stages to be easily and economically integrated into scanning procedures. Since an ActiveX application has its own user-interface, it can be independently tested. The ActiveX application then runs (visibly or invisibly) under DAQ software control. Automation capabilities are accessed via a built-in spectro-BASIC language with industry-standard (VBA-compatible) syntax. Supplementing ActiveX, spectro-BASIC also includes auxiliary serial port commands for interfacing programmable logic controllers (PLC). A typical application is automatic filter handling.

  10. ORIGAMI Automator Primer. Automated ORIGEN Source Terms and Spent Fuel Storage Pool Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wieselquist, William A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Thompson, Adam B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bowman, Stephen M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Peterson, Joshua L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-04-01

    Source terms and spent nuclear fuel (SNF) storage pool decay heat load analyses for operating nuclear power plants require a large number of Oak Ridge Isotope Generation and Depletion (ORIGEN) calculations. SNF source term calculations also require a significant amount of bookkeeping to track quantities such as core and assembly operating histories, spent fuel pool (SFP) residence times, heavy metal masses, and enrichments. The ORIGEN Assembly Isotopics (ORIGAMI) module in the SCALE code system provides a simple scheme for entering these data. However, given the large scope of the analysis, extensive scripting is necessary to convert formats and process data to create thousands of ORIGAMI input files (one per assembly) and to process the results into formats readily usable by follow-on analysis tools. This primer describes a project within the SCALE Fulcrum graphical user interface (GUI) called ORIGAMI Automator that was developed to automate the scripting and bookkeeping in large-scale source term analyses. The ORIGAMI Automator enables the analyst to (1) easily create, view, and edit the reactor site and assembly information, (2) automatically create and run ORIGAMI inputs, and (3) analyze the results from ORIGAMI. ORIGAMI Automator uses the standard ORIGEN binary concentrations files produced by ORIGAMI, with concentrations available at all time points in each assembly’s life. The GUI plots results such as mass, concentration, activity, and decay heat using a powerful new ORIGEN Post-Processing Utility for SCALE (OPUS) GUI component. This document includes a description and user guide for the GUI, a step-by-step tutorial for a simplified scenario, and appendices that document the file structures used.

  11. Simplified models for dark matter searches at the LHC

    NARCIS (Netherlands)

    J. Abdallah; . et al; P. de Jong; S. Liem; C. McCabe; P. Pani; D. Salek; C. Tunnell

    2015-01-01

    This document outlines a set of simplified models for dark matter and its interactions with Standard Model particles. It is intended to summarize the main characteristics that these simplified models have when applied to dark matter searches at the LHC, and to provide a number of useful expressions

  12. Communication: A simplified coupled-cluster Lagrangian for polarizable embedding.

    Science.gov (United States)

    Krause, Katharina; Klopper, Wim

    2016-01-28

    A simplified coupled-cluster Lagrangian, which is linear in the Lagrangian multipliers, is proposed for the coupled-cluster treatment of a quantum mechanical system in a polarizable environment. In the simplified approach, the amplitude equations are decoupled from the Lagrangian multipliers and the energy obtained from the projected coupled-cluster equation corresponds to a stationary point of the Lagrangian. PMID:26827193

  13. Naturally Simplified Input, Comprehension, and Second Language Acquisition.

    Science.gov (United States)

    Ellis, Rod

    This article examines the concept of simplification in second language (SL) learning, reviewing research on the simplified input that both naturalistic and classroom SL learners receive. Research indicates that simplified input, particularly if derived from naturally occurring interactions, does aid comprehension but has not been shown to…

  14. Communication: A simplified coupled-cluster Lagrangian for polarizable embedding

    International Nuclear Information System (INIS)

    A simplified coupled-cluster Lagrangian, which is linear in the Lagrangian multipliers, is proposed for the coupled-cluster treatment of a quantum mechanical system in a polarizable environment. In the simplified approach, the amplitude equations are decoupled from the Lagrangian multipliers and the energy obtained from the projected coupled-cluster equation corresponds to a stationary point of the Lagrangian

  15. 26 CFR 1.41-9 - Alternative simplified credit.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Alternative simplified credit. 1.41-9 Section 1.41-9 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY INCOME TAX INCOME TAXES Credits Against Tax § 1.41-9 Alternative simplified credit. For further guidance, see § 1.41-9T....

  16. Communication: A simplified coupled-cluster Lagrangian for polarizable embedding

    Energy Technology Data Exchange (ETDEWEB)

    Krause, Katharina; Klopper, Wim, E-mail: klopper@kit.edu [Karlsruhe Institute of Technology (KIT), Institute of Physical Chemistry, Theoretical Chemistry Group, KIT Campus South, P.O. Box 6980, 76049 Karlsruhe (Germany)

    2016-01-28

    A simplified coupled-cluster Lagrangian, which is linear in the Lagrangian multipliers, is proposed for the coupled-cluster treatment of a quantum mechanical system in a polarizable environment. In the simplified approach, the amplitude equations are decoupled from the Lagrangian multipliers and the energy obtained from the projected coupled-cluster equation corresponds to a stationary point of the Lagrangian.

  17. A Simplified HTTR Diffusion Theory Benchmark

    International Nuclear Information System (INIS)

    The Georgia Institute of Technology (GA-Tech) recently developed a transport theory benchmark based closely on the geometry and the features of the HTTR reactor that is operational in Japan. Though simplified, the benchmark retains all the principal physical features of the reactor and thus provides a realistic and challenging test for the codes. The purpose of this paper is two-fold. The first goal is an extension of the benchmark to diffusion theory applications by generating the additional data not provided in the GA-Tech prior work. The second goal is to use the benchmark on the HEXPEDITE code available to the INL. The HEXPEDITE code is a Green's function-based neutron diffusion code in 3D hexagonal-z geometry. The results showed that the HEXPEDITE code accurately reproduces the effective multiplication factor of the reference HELIOS solution. A secondary, but no less important, conclusion is that in the testing against actual HTTR data of a full sequence of codes that would include HEXPEDITE, in the apportioning of inevitable discrepancies between experiment and models, the portion of error attributable to HEXPEDITE would be expected to be modest. If large discrepancies are observed, they would have to be explained by errors in the data fed into HEXPEDITE. Results based on a fully realistic model of the HTTR reactor are presented in a companion paper. The suite of codes used in that paper also includes HEXPEDITE. The results shown here should help that effort in the decision making process for refining the modeling steps in the full sequence of codes.

  18. Automated tuning of the advanced photon source booster synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Biedron, S.G.; Milton, S.V.

    1997-08-01

    The acceleration cycle of the Advanced Photon Source (APS) booster synchrotron is completed within 223 ms and is repeated at 2 Hz. Unless properly corrected, transverse and longitudinal injection errors can lead to inefficient booster performance. In order to simplify daily operation, automated tuning methods have been developed. Through the use of beam position monitor (BPM) reading, transfer line corrector magnets, magnet ramp timing, and empirically determined response functions, the injection process is optimized by correcting the first turn trajectory to the measured closed orbit. These tuning algorithms and their implementation are described here along with an evaluation of their performance.

  19. Fully automated setup for high temperature Seebeck coefficient measurement

    CERN Document Server

    Patel, Ashutosh

    2016-01-01

    In this work, we report the fabrication of fully automated experimental setup for high temperature Seebeck coefficient ($\\alpha$) measurement. The K-type thermocouples are used to measure the average temperature of the sample and Seebeck voltage (SV) across it. The temperature dependence of the Seebeck coefficients of the thermocouple and its negative leg is taken care by using the integration method. Steady state based differential technique is used for $\\alpha$ measurement. Use of limited component and thin heater simplify the sample holder design and minimize the heat loss. The power supplied to the heater decides temperature difference across the sample and measurement is carried out by achieving the steady state. The LabVIEW based program is built to automize the whole measurement process. The complete setup is fabricated by using commonly available materials in the market. This instrument is standardized for materials with a wide range of $\\alpha$ and for the wide range of $\\Delta T$ across the specimen...

  20. 特发性全身性癫痫患者脑灰质结构基于体素的形态学测量的研究%Voxel-based morphometry study of the gray matter structure in idiopathic generalized epilepsy

    Institute of Scientific and Technical Information of China (English)

    张成周; 王萍; 张敬; 姜兴岳; 张林; 张云亭

    2012-01-01

    目的 运用基于体素的形态学测量(VBM)方法分析特发性全身性癫痫患者(IGE)和正常人全脑灰质体积的差异.方法采用GE 3.0T HDX 超导型磁共振扫描仪对28例IGE患者和25例正常对照进行全脑高分辨解剖像扫描.在Matlab 7.0平台上采用SPM5软件包对图像进行处理.采用双样本t检验,将P< 0.005、像素簇大小>200个体素的脑区作为有统计学差异的脑区.结果 与正常对照相比,IGE患者显示双侧大脑半球广泛脑区的灰质体积减少,包括双侧扣带回、双侧额中回、右侧额上回、右侧额叶直回、右楔叶、左侧尾状核头;与正常对照相比IGE患者灰质体积增加的脑区包括左侧颞上回、左侧屏状核、右侧豆状核.结论 VBM能揭示IGE患者存在广泛脑区灰质密度异常,灰质密度减低脑区多与认知功能相关,是引起癫痫患者认知功能下降的原因之一.%Objective To analyze the structural changes of whole brain gray matter in patients with idiopathic generalized epilepsy (IGE) by using voxel-based morphomctryf VBM). Methods Twenty eight patients with IGK and twenty five normal subjects were recruited in our study, GE 3. 0T HDX MR scanner was used to obtain T1 WI three-dimensional brain volume sequences. The data were processed with SPM5 in Matlab 7. 0. Intcr-group analysis was performed with two t-tcst, the regions in the brain that P< 0. 005, cluster size more than 200 voxels were seemed as significantly different. Results Compared to normal subjects, IGE patients showed extensive decrease of gray matter volume in widespread brain regions, including bilateral cingulatc cortex, bilateral middle frontal cortex, right superior frontal cortex, right rcctus gyrus, right cuncus, left caudate nucleus head. Compared to normal subjects, IGE patients showed increase of gray matter volume in left superior temporal gyrus, left claustrum and right lentiform nucleus. Conclusion VBM can evaluate the widespread gray

  1. Simplifying CEA through Excel, VBA, and Subeq

    Science.gov (United States)

    Foster, Ryan

    2004-01-01

    Many people use compound equilibrium programs for very different reasons, varying from refrigerators to light bulbs to rockets. A commonly used equilibrium program is CEA. CEA can take various inputs such as pressure, temperature, and volume along with numerous reactants and run them through equilibrium equations to obtain valuable output information, including products formed and their relative amounts. A little over a year ago, Bonnie McBride created the program subeq with the goal to simplify the calling of CEA. Subeq was also designed to be called by other programs, including Excel, through the use of Visual Basic for Applications (VBA). The largest advantage of using Excel is that it allows the user to input the information in a colorful and user-friendly environment while allowing VBA to run subeq, which is in the form of a FORTRAN DLL (Dynamic Link Library). Calling subeq in this form makes it much faster than if it were converted to VBA. Since subeq requires such large lists of reactant and product names, all of which can't be passed in as an array, subeq had to be changed to accept very long strings of reactants and products. To pass this string and adjust the transfer of input and output parameters, the subeq DLL had to be changed. One program that does this is Compaq Visual FORTRAN, which allows DLLs to be edited, debugged, and compiled. Compaq Visual FORTRAN uses FORTRAN 90/95, which has additional features to that of FORTRAN 77. My goals this summer include finishing up the excel spreadsheet of subeq, which I started last summer, and putting it on the Internet so that others can use it without having to download my spreadsheet. To finish up the spreadsheet I will need to work on debugging current options and problems. I will also work on making it as robust as possible, so that all errors that may arise will be clearly communicated to the user. New features will be added old ones will be changed as I receive comments from people using the spreadsheet

  2. Automation and Intensity Modulated Radiation Therapy for Individualized High-Quality Tangent Breast Treatment Plans

    International Nuclear Information System (INIS)

    Purpose: To demonstrate the large-scale clinical implementation and performance of an automated treatment planning methodology for tangential breast intensity modulated radiation therapy (IMRT). Methods and Materials: Automated planning was used to prospectively plan tangential breast IMRT treatment for 1661 patients between June 2009 and November 2012. The automated planning method emulates the manual steps performed by the user during treatment planning, including anatomical segmentation, beam placement, optimization, dose calculation, and plan documentation. The user specifies clinical requirements of the plan to be generated through a user interface embedded in the planning system. The automated method uses heuristic algorithms to define and simplify the technical aspects of the treatment planning process. Results: Automated planning was used in 1661 of 1708 patients receiving tangential breast IMRT during the time interval studied. Therefore, automated planning was applicable in greater than 97% of cases. The time for treatment planning using the automated process is routinely 5 to 6 minutes on standard commercially available planning hardware. We have shown a consistent reduction in plan rejections from plan reviews through the standard quality control process or weekly quality review multidisciplinary breast rounds as we have automated the planning process for tangential breast IMRT. Clinical plan acceptance increased from 97.3% using our previous semiautomated inverse method to 98.9% using the fully automated method. Conclusions: Automation has become the routine standard method for treatment planning of tangential breast IMRT at our institution and is clinically feasible on a large scale. The method has wide clinical applicability and can add tremendous efficiency, standardization, and quality to the current treatment planning process. The use of automated methods can allow centers to more rapidly adopt IMRT and enhance access to the documented

  3. Automated Preferences Elicitation

    Czech Academy of Sciences Publication Activity Database

    Kárný, Miroslav; Guy, Tatiana Valentine

    Prague : Institute of Information Theory and Automation, 2011, s. 20-25. ISBN 978-80-903834-6-3. [The 2nd International Workshop od Decision Making with Multiple Imperfect Decision Makers. Held in Conjunction with the 25th Annual Conference on Neural Information Processing Systems (NIPS 2011). Sierra Nevada (ES), 16.12.2011-16.12.2011] R&D Projects: GA MŠk 1M0572; GA ČR GA102/08/0567 Institutional research plan: CEZ:AV0Z10750506 Keywords : elicitation * decision making * Bayesian decision making * fully probabilistic design Subject RIV: BB - Applied Statistics, Operational Research http://library.utia.cas.cz/separaty/2011/AS/karny-automated preferences elicitation.pdf

  4. Automated drawing generation system

    International Nuclear Information System (INIS)

    Since automated CAD drawing generation systems still require human intervention, improvements were focussed on an interactive processing section (data input and correcting operation) which necessitates a vast amount of work. As a result, human intervention was eliminated, the original objective of a computerized system. This is the first step taken towards complete automation. The effects of development and commercialization of the system are as described below. (1) The interactive processing time required for generating drawings was improved. It was determined that introduction of the CAD system has reduced the time required for generating drawings. (2) The difference in skills between workers preparing drawings has been eliminated and the quality of drawings has been made uniform. (3) The extent of knowledge and experience demanded of workers has been reduced. (author)

  5. Terminal automation system maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Coffelt, D.; Hewitt, J. [Engineered Systems Inc., Tempe, AZ (United States)

    1997-01-01

    Nothing has improved petroleum product loading in recent years more than terminal automation systems. The presence of terminal automation systems (TAS) at loading racks has increased operational efficiency and safety and enhanced their accounting and management capabilities. However, like all finite systems, they occasionally malfunction or fail. Proper servicing and maintenance can minimize this. And in the unlikely event a TAS breakdown does occur, prompt and effective troubleshooting can reduce its impact on terminal productivity. To accommodate around-the-clock loading at racks, increasingly unattended by terminal personnel, TAS maintenance, servicing and troubleshooting has become increasingly demanding. It has also become increasingly important. After 15 years of trial and error at petroleum and petrochemical storage and transfer terminals, a number of successful troubleshooting programs have been developed. These include 24-hour {open_quotes}help hotlines,{close_quotes} internal (terminal company) and external (supplier) support staff, and {open_quotes}layered{close_quotes} support. These programs are described.

  6. ATLAS Distributed Computing Automation

    CERN Document Server

    Schovancova, J; The ATLAS collaboration; Borrego, C; Campana, S; Di Girolamo, A; Elmsheuser, J; Hejbal, J; Kouba, T; Legger, F; Magradze, E; Medrano Llamas, R; Negri, G; Rinaldi, L; Sciacca, G; Serfon, C; Van Der Ster, D C

    2012-01-01

    The ATLAS Experiment benefits from computing resources distributed worldwide at more than 100 WLCG sites. The ATLAS Grid sites provide over 100k CPU job slots, over 100 PB of storage space on disk or tape. Monitoring of status of such a complex infrastructure is essential. The ATLAS Grid infrastructure is monitored 24/7 by two teams of shifters distributed world-wide, by the ATLAS Distributed Computing experts, and by site administrators. In this paper we summarize automation efforts performed within the ATLAS Distributed Computing team in order to reduce manpower costs and improve the reliability of the system. Different aspects of the automation process are described: from the ATLAS Grid site topology provided by the ATLAS Grid Information System, via automatic site testing by the HammerCloud, to automatic exclusion from production or analysis activities.

  7. Rapid automated nuclear chemistry

    International Nuclear Information System (INIS)

    Rapid Automated Nuclear Chemistry (RANC) can be thought of as the Z-separation of Neutron-rich Isotopes by Automated Methods. The range of RANC studies of fission and its products is large. In a sense, the studies can be categorized into various energy ranges from the highest where the fission process and particle emission are considered, to low energies where nuclear dynamics are being explored. This paper presents a table which gives examples of current research using RANC on fission and fission products. The remainder of this text is divided into three parts. The first contains a discussion of the chemical methods available for the fission product elements, the second describes the major techniques, and in the last section, examples of recent results are discussed as illustrations of the use of RANC

  8. Rapid automated nuclear chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, R.A.

    1979-05-31

    Rapid Automated Nuclear Chemistry (RANC) can be thought of as the Z-separation of Neutron-rich Isotopes by Automated Methods. The range of RANC studies of fission and its products is large. In a sense, the studies can be categorized into various energy ranges from the highest where the fission process and particle emission are considered, to low energies where nuclear dynamics are being explored. This paper presents a table which gives examples of current research using RANC on fission and fission products. The remainder of this text is divided into three parts. The first contains a discussion of the chemical methods available for the fission product elements, the second describes the major techniques, and in the last section, examples of recent results are discussed as illustrations of the use of RANC.

  9. Automated Microbial Metabolism Laboratory

    Science.gov (United States)

    1973-01-01

    Development of the automated microbial metabolism laboratory (AMML) concept is reported. The focus of effort of AMML was on the advanced labeled release experiment. Labeled substrates, inhibitors, and temperatures were investigated to establish a comparative biochemical profile. Profiles at three time intervals on soil and pure cultures of bacteria isolated from soil were prepared to establish a complete library. The development of a strategy for the return of a soil sample from Mars is also reported.

  10. Components for automated microscopy

    Science.gov (United States)

    Determann, H.; Hartmann, H.; Schade, K. H.; Stankewitz, H. W.

    1980-12-01

    A number of devices, aiming at automated analysis of microscopic objects as regards their morphometrical parameters or their photometrical values, were developed. These comprise: (1) a device for automatic focusing tuned on maximum contrast; (2) a feedback system for automatic optimization of microscope illumination; and (3) microscope lenses with adjustable pupil distances for usage in the two previous devices. An extensive test program on histological and zytological applications proves the wide application possibilities of the autofocusing device.

  11. Automation of dissolution tests

    OpenAIRE

    Rolf Rolli

    2003-01-01

    Dissolution testing of drug formulations was introduced in the 1960s and accepted by health regulatory authorities in the 1970s. Since then, the importance of dissolution has grown rapidly as have the number of tests and demands in quality-control laboratories. Recent research works lead to the development of in-vitro dissolution tests as replacements for human and animal bioequivalence studies. For many years, a lot of time and effort has been invested in automation of dissolution tests. The...

  12. Automated uranium assays

    International Nuclear Information System (INIS)

    Precise, timely inventories of enriched uranium stocks are vital to help prevent the loss, theft, or diversion of this material for illicit use. A wet-chemistry analyzer has been developed at LLL to assist in these inventories by performing automated analyses of uranium samples from different stages in the nuclear fuel cycle. These assays offer improved accuracy, reduced costs, significant savings in manpower, and lower radiation exposure for personnel compared with present techniques

  13. Construction Automation and Robotics

    OpenAIRE

    Bock, Thomas

    2008-01-01

    Due to the high complexity of the construction process and the stagnating technological development a long-term preparation is necessary to adapt it to advanced construction methods. Architects, engineers and all other participants of the construction process have to be integrated in this adaptation process. The short- and long-term development of automation will take place step-by-step and will be oriented to the respective application and requirements. In the initial phase existing building...

  14. Shielded cells transfer automation

    International Nuclear Information System (INIS)

    Nuclear waste from shielded cells is removed, packaged, and transferred manually in many nuclear facilities. To reduce radiation exposure to operators, technological advances in remote handling and automation were employed. An industrial robot and a specially designed end effector, access port, and sealing machine were used to remotely bag waste containers out of a glove box. The system is operated from a control panel outside the work area via television cameras

  15. Generic simplified simulation model for DFIG with active crowbar

    Energy Technology Data Exchange (ETDEWEB)

    Buendia, Francisco Jimenez [Gamesa Innovation and Technology, Sarriguren, Navarra (Spain). Technology Dept.; Barrasa Gordo, Borja [Assystem Iberia, Bilbao, Vizcaya (Spain)

    2012-07-01

    Simplified models for transient stability studies are a general requirement for transmission system operators to wind turbine (WTG) manufacturers. Those models must represent the performance of the WTGs for transient stability studies, mainly voltage dips originated by short circuits in the electrical network. Those models are implemented in simulation software as PSS/E, DigSilent or PSLF. Those software platforms allow simulation of transients in large electrical networks with thousands of busses, generators and loads. The high complexity of the grid requires that the models inserted into the grid should be simplified in order to allow the simulations being executed as fast as possible. The development of a model which is simplified enough to be integrated in those complex grids and represent the performance of WTG is a challenge. The IEC TC88 working group has developed generic models for different types of generators, among others for WTGs using doubly fed induction generators (DFIG). This paper will focus in an extension of the models for DFIG WTGs developed in IEC in order to be able to represent the simplified model of DFIG with an active crowbar, which is required to withstand voltage dips without disconnecting from the grid. This paper improves current generic model of Type 3 for DFIG adding a simplified version of the generator including crowbar functionality and a simplified version of the crowbar firing. In addition, this simplified model is validated by correlation with voltage dip field test from a real wind turbine. (orig.)

  16. LINAC control automation system

    International Nuclear Information System (INIS)

    A 7 MeV Electron Beam Linear Accelerator (LINAC) being used for pulse radiolysis experiments at RC and CDD, B.A.R.C. has been automated with a PLC based control panel designed and developed by Computer Division, B.A.R.C.. The control panel after power on switches ON various units in a pre-defined sequence and intervals on a single turn of START key from OFF to ON position. The control panel also generates various ramp signals in a pre-defined sequence and rate and steady values and feeds to the LINAC bringing it to the ready for experiment condition. Similarly on a single turn of STOP key from OFF to ON position, the panel ramps down the various signals in pre-defined manners and makes OFF the various units in predefined sequence and timing providing safety to the machine. The steady values for various signals are on line settable as and when required so. This automation system relieves the operator from fatigue of time consuming manual ramping up or down of various signals and running around in four rooms for switching ON or OFF the various units enhancing efficiency and safety. This also facilitates the user scientist to do start up and shutdown operation in the absence of skilled operators and thus adds flexibility for working up to extended timing. This unit has been working satisfactorily since August 2002. For extraordinary condition automation to manual or vice versa change over has been provided. (author)

  17. Automation of a phospho-STAT5 staining procedure for flow cytometry for application in drug discovery

    NARCIS (Netherlands)

    Malergue, Fabrice; van Agthoven, Andreas; Scifo, Caroline; Egan, Dave; Strous, Ger J

    2015-01-01

    Drug discovery often requires the screening of compound libraries on tissue cultured cells. Some major targets in drug discovery belong to signal transduction pathways, and PerFix EXPOSE* allows easy flow cytometry phospho assays. We thus investigated the possibility to further simplify and automate

  18. Simplified Models for Dark Matter Searches at the LHC

    CERN Document Server

    Abdallah, Jalal; Arbey, Alexandre; Ashkenazi, Adi; Belyaev, Alexander; Berger, Joshua; Boehm, Celine; Boveia, Antonio; Brennan, Amelia; Brooke, Jim; Buchmueller, Oliver; Buckley, Matthew; Busoni, Giorgio; Calibbi, Lorenzo; Chauhan, Sushil; Daci, Nadir; Davies, Gavin; De Bruyn, Isabelle; de Jong, Paul; De Roeck, Albert; de Vries, Kees; del Re, Daniele; De Simone, Andrea; Di Simone, Andrea; Doglioni, Caterina; Dolan, Matthew; Dreiner, Herbi K.; Ellis, John; Eno, Sarah; Etzion, Erez; Fairbairn, Malcolm; Feldstein, Brian; Flaecher, Henning; Feng, Eric; Fox, Patrick; Genest, Marie-Hélène; Gouskos, Loukas; Gramling, Johanna; Haisch, Ulrich; Harnik, Roni; Hibbs, Anthony; Hoh, Siewyan; Hopkins, Walter; Ippolito, Valerio; Jacques, Thomas; Kahlhoefer, Felix; Khoze, Valentin V.; Kirk, Russell; Korn, Andreas; Kotov, Khristian; Kunori, Shuichi; Landsberg, Greg; Liem, Sebastian; Lin, Tongyan; Lowette, Steven; Lucas, Robyn; Malgeri, Luca; Malik, Sarah; McCabe, Christopher; Mete, Alaettin Serhan; Morgante, Enrico; Mrenna, Stephen; Nakahama, Yu; Newbold, Dave; Nordstrom, Karl; Pani, Priscilla; Papucci, Michele; Pataraia, Sophio; Penning, Bjoern; Pinna, Deborah; Polesello, Giacomo; Racco, Davide; Re, Emanuele; Riotto, Antonio Walter; Rizzo, Thomas; Salek, David; Sarkar, Subir; Schramm, Steven; Skubic, Patrick; Slone, Oren; Smirnov, Juri; Soreq, Yotam; Sumner, Timothy; Tait, Tim M.P.; Thomas, Marc; Tomalin, Ian; Tunnell, Christopher; Vichi, Alessandro; Volansky, Tomer; Weiner, Neal; West, Stephen M.; Wielers, Monika; Worm, Steven; Yavin, Itay; Zaldivar, Bryan; Zhou, Ning; Zurek, Kathryn

    2015-01-01

    This document outlines a set of simplified models for dark matter and its interactions with Standard Model particles. It is intended to summarize the main characteristics that these simplified models have when applied to dark matter searches at the LHC, and to provide a number of useful expressions for reference. The list of models includes both s-channel and t-channel scenarios. For s-channel, spin-0 and spin-1 mediation is discussed, and also realizations where the Higgs particle provides a portal between the dark and visible sectors. The guiding principles underpinning the proposed simplified models are spelled out, and some suggestions for implementation are presented.

  19. Simplified procedure for controlling pressure distribution of a scramjet combustor

    Institute of Scientific and Technical Information of China (English)

    Cui Tao

    2014-01-01

    Scramjet engines are used at extreme temperatures and velocity. New control problems involving distributed parameter control have been found concerning investigations of the control of scramjet engines whose physical states are spatially interacted. Succeeding the existing theoretical studies on the distributed parameter control for scramjet engines, this paper puts forward a simplified distributed parameter control approach for scramjet engines aimed at engineering appli-cation. The simplified control procedure uses the classical proportional-integral (PI) compensation to control the target pressure distribution of scramjet engines, which is effective and applicable for practical implements. Simulation results show the validation of the simplified distributed parameter control procedure.

  20. M2m Automation: Matlab-To-Map Reduce Automation

    Directory of Open Access Journals (Sweden)

    Archana C S

    2014-06-01

    Full Text Available Abstract- MapReduce is a very popular parallel programming model for cloud computing platforms, and has become an effective method for processing massive data by using a cluster of computers. Program language -to-MapReduce Automator is a possible solution to help traditional programmers easily deploy an application to cloud systems through translating sequential codes to MapReduce codes.M2M Automation mainly focuses on automating numerical computations by using hadoop at the back end. M2M automates Hadoop, for faster execution of Matlab commands using MapReduce code.

  1. Photographic and drafting techniques simplify method of producing engineering drawings

    Science.gov (United States)

    Provisor, H.

    1968-01-01

    Combination of photographic and drafting techniques has been developed to simplify the preparation of three dimensional and dimetric engineering drawings. Conventional photographs can be converted to line drawings by making copy negatives on high contrast film.

  2. 48 CFR 1532.003 - Simplified acquisition procedures financing.

    Science.gov (United States)

    2010-10-01

    ... procedures financing. 1532.003 Section 1532.003 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY GENERAL CONTRACTING REQUIREMENTS CONTRACT FINANCING 1532.003 Simplified acquisition procedures financing. (a) Scope. This subpart provides for authorization of advance and interim payments...

  3. 48 CFR 32.003 - Simplified acquisition procedures financing.

    Science.gov (United States)

    2010-10-01

    ... procedures financing. 32.003 Section 32.003 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION GENERAL CONTRACTING REQUIREMENTS CONTRACT FINANCING 32.003 Simplified acquisition procedures financing. Unless agency regulations otherwise permit, contract financing shall not be provided...

  4. S-Channel Dark Matter Simplified Models and Unitarity

    OpenAIRE

    Englert, Christoph; McCullough, Matthew; Spannowsky, Michael

    2016-01-01

    The ultraviolet structure of $s$-channel mediator dark matter simplified models at hadron colliders is considered. In terms of commonly studied $s$-channel mediator simplified models it is argued that at arbitrarily high energies the perturbative description of dark matter production in high energy scattering at hadron colliders will break down in a number of cases. This is analogous to the well documented breakdown of an EFT description of dark matter collider production. With this in mind, ...

  5. Access and comprehension - Teachers use of simplified language materials

    OpenAIRE

    Rix, Jonathan

    2004-01-01

    This paper examines the current use of simplified language materials (SLMs) by primary and secondary teachers across England. Drawing on a survey of 33 schools the paper examines the degree to which teachers and support teachers currently use simplified language materials and the reasons they give for their usage. It discusses both the contradictions and similarities between teachers' perceptions of the value of SLMs and the existing research base. It focuses on current national guidance, the...

  6. Automated Assessment, Face to Face

    OpenAIRE

    Rizik M. H. Al-Sayyed; Amjad Hudaib; Muhannad AL-Shboul; Yousef Majdalawi; Mohammed Bataineh

    2010-01-01

    This research paper evaluates the usability of automated exams and compares them with the paper-and-pencil traditional ones. It presents the results of a detailed study conducted at The University of Jordan (UoJ) that comprised students from 15 faculties. A set of 613 students were asked about their opinions concerning automated exams; and their opinions were deeply analyzed. The results indicate that most students reported that they are satisfied with using automated exams but they have sugg...

  7. Automation System Products and Research

    OpenAIRE

    Rintala, Mikko; Sormunen, Jussi; Kuisma, Petri; Rahkala, Matti

    2014-01-01

    Automation systems are used in most buildings nowadays. In the past they were mainly used in industry to control and monitor critical systems. During the past few decades the automation systems have become more common and are used today from big industrial solutions to homes of private customers. With the growing need for ecologic and cost-efficient management systems, home and building automation systems are becoming a standard way of controlling lighting, ventilation, heating etc. Auto...

  8. Software Testing and Documenting Automation

    OpenAIRE

    Tsybin, Anton; Lyadova, Lyudmila

    2008-01-01

    This article describes some approaches to problem of testing and documenting automation in information systems with graphical user interface. Combination of data mining methods and theory of finite state machines is used for testing automation. Automated creation of software documentation is based on using metadata in documented system. Metadata is built on graph model. Described approaches improve performance and quality of testing and documenting processes.

  9. Embedded system for building automation

    OpenAIRE

    Rolih, Andrej

    2014-01-01

    Home automation is a fast developing field of computer science and electronics. Companies are offering many different products for home automation. Ranging anywhere from complete systems for building management and control, to simple smart lights that can be connected to the internet. These products offer the user greater living comfort and lower their expenses by reducing the energy usage. This thesis shows the development of a simple home automation system that focuses mainly on the enhance...

  10. World-wide distribution automation systems

    Energy Technology Data Exchange (ETDEWEB)

    Devaney, T.M.

    1994-12-31

    A worldwide power distribution automation system is outlined. Distribution automation is defined and the status of utility automation is discussed. Other topics discussed include a distribution management system, substation feeder, and customer functions, potential benefits, automation costs, planning and engineering considerations, automation trends, databases, system operation, computer modeling of system, and distribution management systems.

  11. AUTOMATED API TESTING APPROACH

    Directory of Open Access Journals (Sweden)

    SUNIL L. BANGARE

    2012-02-01

    Full Text Available Software testing is an investigation conducted to provide stakeholders with information about the quality of the product or service under test. With the help of software testing we can verify or validate the software product. Normally testing will be done after development of software but we can perform the software testing at the time of development process also. This paper will give you a brief introduction about Automated API Testing Tool. This tool of testing will reduce lots of headache after the whole development of software. It saves time as well as money. Such type of testing is helpful in the Industries & Colleges also.

  12. Automated radioimmunoassay of nicotine

    International Nuclear Information System (INIS)

    The authors have developed an automated nonequilibrium procedure for the radioimmunoassay of nicotine. The use of a unique iodinated nicotine derivative in this procedure gave a sensitivity of 10 μg/l for nicotine with a between-run precision of 7.4% and within-run precision of 6.0%. Nicotine levels of 60 to 67 μg/l were found in subjects 15 min after smoking one standard cigarette. The technique herein reported is a very rapid, and sensitive radioimmunoassay for nicotine and facilitates the determination of nicotine in smoking subjects during the actual process of smoking. (Auth.)

  13. Automated Motivic Analysis

    DEFF Research Database (Denmark)

    Lartillot, Olivier

    2016-01-01

    Motivic analysis provides very detailed understanding of musical composi- tions, but is also particularly difficult to formalize and systematize. A computational automation of the discovery of motivic patterns cannot be reduced to a mere extraction of all possible sequences of descriptions....... The systematic approach inexorably leads to a proliferation of redundant structures that needs to be addressed properly. Global filtering techniques cause a drastic elimination of interesting structures that damages the quality of the analysis. On the other hand, a selection of closed patterns allows...

  14. Mechatronic Design Automation

    DEFF Research Database (Denmark)

    Fan, Zhun

    This book proposes a novel design method that combines both genetic programming (GP) to automatically explore the open-ended design space and bond graphs (BG) to unify design representations of multi-domain Mechatronic systems. Results show that the method, formally called GPBG method, can...... successfully design analogue filters, vibration absorbers, micro-electro-mechanical systems, and vehicle suspension systems, all in an automatic or semi-automatic way. It also investigates the very important issue of co-designing plant-structures and dynamic controllers in automated design of Mechatronic...

  15. Automated Analysis of {sup 123}I-beta-CIT SPECT Images with Statistical Probabilistic Anatomical Mapping

    Energy Technology Data Exchange (ETDEWEB)

    Eo, Jae Seon; Lee, Hoyoung; Lee, Jae Sung; Kim, Yu Kyung; Jeon, Bumseok; Lee, Dong Soo [Seoul National Univ., Seoul (Korea, Republic of)

    2014-03-15

    Population-based statistical probabilistic anatomical maps have been used to generate probabilistic volumes of interest for analyzing perfusion and metabolic brain imaging. We investigated the feasibility of automated analysis for dopamine transporter images using this technique and evaluated striatal binding potentials in Parkinson's disease and Wilson's disease. We analyzed 2β-Carbomethoxy-3β-(4-{sup 123}I-iodophenyl)tropane ({sup 123}I-beta-CIT) SPECT images acquired from 26 people with Parkinson's disease (M:F=11:15,mean age=49±12 years), 9 people with Wilson's disease (M: F=6:3, mean age=26±11 years) and 17 normal controls (M:F=5:12, mean age=39±16 years). A SPECT template was created using striatal statistical probabilistic map images. All images were spatially normalized onto the template, and probability-weighted regional counts in striatal structures were estimated. The binding potential was calculated using the ratio of specific and nonspecific binding activities at equilibrium. Voxel-based comparisons between groups were also performed using statistical parametric mapping. Qualitative assessment showed that spatial normalizations of the SPECT images were successful for all images. The striatal binding potentials of participants with Parkinson's disease and Wilson's disease were significantly lower than those of normal controls. Statistical parametric mapping analysis found statistically significant differences only in striatal regions in both disease groups compared to controls. We successfully evaluated the regional {sup 123}I-beta-CIT distribution using the SPECT template and probabilistic map data automatically. This procedure allows an objective and quantitative comparison of the binding potential, which in this case showed a significantly decreased binding potential in the striata of patients with Parkinson's disease or Wilson's disease.

  16. Automated Analysis of 123I-beta-CIT SPECT Images with Statistical Probabilistic Anatomical Mapping

    International Nuclear Information System (INIS)

    Population-based statistical probabilistic anatomical maps have been used to generate probabilistic volumes of interest for analyzing perfusion and metabolic brain imaging. We investigated the feasibility of automated analysis for dopamine transporter images using this technique and evaluated striatal binding potentials in Parkinson's disease and Wilson's disease. We analyzed 2β-Carbomethoxy-3β-(4-123I-iodophenyl)tropane (123I-beta-CIT) SPECT images acquired from 26 people with Parkinson's disease (M:F=11:15,mean age=49±12 years), 9 people with Wilson's disease (M: F=6:3, mean age=26±11 years) and 17 normal controls (M:F=5:12, mean age=39±16 years). A SPECT template was created using striatal statistical probabilistic map images. All images were spatially normalized onto the template, and probability-weighted regional counts in striatal structures were estimated. The binding potential was calculated using the ratio of specific and nonspecific binding activities at equilibrium. Voxel-based comparisons between groups were also performed using statistical parametric mapping. Qualitative assessment showed that spatial normalizations of the SPECT images were successful for all images. The striatal binding potentials of participants with Parkinson's disease and Wilson's disease were significantly lower than those of normal controls. Statistical parametric mapping analysis found statistically significant differences only in striatal regions in both disease groups compared to controls. We successfully evaluated the regional 123I-beta-CIT distribution using the SPECT template and probabilistic map data automatically. This procedure allows an objective and quantitative comparison of the binding potential, which in this case showed a significantly decreased binding potential in the striata of patients with Parkinson's disease or Wilson's disease

  17. Impact of Mastering Traditional Characters to Learn Simplified Characters in Analogy Simplified Picto-phonogram Characters as Reference

    OpenAIRE

    Sugiato Lim

    2014-01-01

    There are a number of Southeast Asian students begin to learn Chinese in their own country based on traditional Chinese characters. Therefore, author based on own learning experience talked about the influence of mastering traditional characters to learn simplified Chinese characters. By collecting the traditional character texts, summarizing the occurrence of error categories of simplified Chinese characters, and based on the Chinese character simplification methods in Fan Jian Z...

  18. Automated Traffic Surveillance: Evolution and Implementation

    Directory of Open Access Journals (Sweden)

    Kriti Bhandari

    2013-08-01

    Full Text Available The rampant growth in use of four-wheelers has led to an increase in road congestion at all signal points. In the light of time constraints, drivers find an easier way out by breaking signals. Presently, our defense against such practices lies at the mercy of traffic policemen stationed at various signal points in the city and monitoring of surveillance cameras. However, constant manual monitoring is not always feasible because of limited manpower. Also, while the use of CCTV cameras only aids in monitoring, fine deduction is still looked after by individual traffic authorities. This system of automated surveillance is based on wireless RF transmission and circumvents the need of expensive wired fiber optic cables. The three key elements of this system include (a infrared transmitter and sensor (b a dual state transmitting system (c a control room managing the data base. The motion of a vehicle passing the pre-established line near the signal is judged by the infrared arrangement, including the strip of sensors on the lower surface of the vehicle under consideration and the IR transmitter on the surface of the road, precisely on the above mentioned limiting line at the signal. The presence of the vehicle thus detected will be accounted for by a transmitter installed in it, thus changing its regular state of transmission and providing the unique number of the offender’s vehicle to the control room. The transmission stage works on the RF frequency. FSK modulation being a reliable and apt scheme has been used for the purpose of modulation of data. This brings us to the next stage of the project dealing with the data base matching and there after sending a plan of action to the undersigned bank of the user wherein the fine deduction process will be initiated. Thus in this paper, we focus on simplifying surveillance by introducing automated monitoring system.

  19. The brain structures related to emotional memory in the elderly: a voxel-based morphometry study%老年人情绪记忆相关脑结构改变基于体素形态学测量研究

    Institute of Scientific and Technical Information of China (English)

    宋文; 王海宝; 徐丽艳; 潘豪; 刘福军; 余永强

    2011-01-01

    Objective To explore morphological characters of brain regions related to the enhancement effect of emotional memory,brain volume of old adult and behavioral performance of emotional memory were measured, combining voxel-based morphometry (VBM) and behavior. Methods 47 healthy elderly samples, the experimental processes included MRI and behavioral performance of emotional memory which have two phases, encoding and retrieval phase. Behavioral performance was recorded and whole-brain 3D MRI data were acquired via 3.0T MRI. 3D MRI data were segmented by VBM5 and whole-brain volume of gray matter, white matter and CSF were produced. SPM5 and SPSS13.0 were used for statistical analysis of 3D MRI data and behavioral data, respectively. Results In old adult, retrieval accuracy of emotional pictures were higher than that of neutral pictures ( t=2.08, P=0.04). Retrieval accuracy of the two pictures has a significant negative correlation with age (neutral: r=0.58, P=0.00; emotion: r=0.30, P=0.04 ), but the emotional memory enhancement effect is a significant positive correlation with age (r=0.37, P=0.01 ). Brain regions related to emotion enhancement effect included left dorsal-lateral prefrontal lobe and right occipital lobe. Conclusion This study confirms that old people behavior scores gradually decline with aging, but emotional memory enhancement effect remained, and from brain morphology level we confirmed the dorsal-lateral prefrontal and occipital lobe brain regions are the important brain structure keeping enhanced effect of emotional memory, thus further expanded related functional imaging studies results.%目的 采用基于体素形态学测量(VBM)和行为学相结合的方法,检测老年人全脑容积及情绪记忆成绩,以探讨老年人情绪记忆增强效应相关脑区形态学特点.方法 47名健康老年人参加实验.实验过程包括情绪记忆行为学检测和MRI两个阶段,其中行为学检测包括记忆编码和再认,

  20. 采用优化的基于体素的形态学方法研究智力障碍儿童脑灰质容积变化%Investigation of the alteration of gray matter volume in children with mental retardation with the optimal voxel-based morphometry

    Institute of Scientific and Technical Information of China (English)

    袁新宇; 谢晟; 肖江喜; 张远哲; 蒋学祥; 金春华; 白振华; 仪晓立

    2011-01-01

    Objective To detect brain structural difference between children with unexplained mental retardation and children with typically normal development. Methods The high-resolution magnetic MR imaging were obtained from 21 children with unexplained mental retardation and 30 age-matched control children without intellectual disabilities. Voxel-based morphometry analysis with an optimization of spatial segmentation and normalization procedures were applied to compare differences of gray matter volume between the two groups. The total and regional gray matter volume were compared between the two groups with independent t test. Meanwhile, correlation was conducted to analyze the relationship between the total gray matter volume and intelligence quotient (IQ) with partial correlation test. Results The total gray matter volume was significantly increased in the mental retardation children [(1. 012 ±0. 079) × 106 mm3]in relative to the controls [(0. 956 ± 0. 059) × 106 mm3, t = - 2. 80, P < 0. 05]. Compared to controls,children with unexplained mental retardation showed significantly increased gray matter volume in different regions, including the bilateral thalami, the bilateral superior frontal gyri, the bilateral gyri rectus, the bilateral temporal poles, the right inferior frontal gyrus, right parahippocampal gyrus and the right cerebellum. No correlation was detected between the total gray matter volume and IQ in children with mental retardation (r = 0. 078 ,P > 0. 05). Conclusions VBM would detect the gray matter abnormalities that were not founded in routine MR scanning. The increase of gray matter volume in the frontal-thalamus network might indicate the delayed maturation of the brain development. This might be one of the causations of mental retardation in children.%目的 利用优化的基于体素的形态测量学(VBM)方法,比较病因不明且常规影像检查正常的智力障碍儿童与正常同龄儿童脑灰质容积的差异,探究患儿脑灰