WorldWideScience

Sample records for gray level images

  1. Underwater Image Enhancement by Adaptive Gray World and Differential Gray-Levels Histogram Equalization

    Directory of Open Access Journals (Sweden)

    WONG, S.-L.

    2018-05-01

    Full Text Available Most underwater images tend to be dominated by a single color cast. This paper presents a solution to remove the color cast and improve the contrast in underwater images. However, after the removal of the color cast using Gray World (GW method, the resultant image is not visually pleasing. Hence, we propose an integrated approach using Adaptive GW (AGW and Differential Gray-Levels Histogram Equalization (DHE that operate in parallel. The AGW is applied to remove the color cast while DHE is used to improve the contrast of the underwater image. The outputs of both chromaticity components of AGW and intensity components of DHE are combined to form the enhanced image. The results of the proposed method are compared with three existing methods using qualitative and quantitative measures. The proposed method increased the visibility of underwater images and in most cases produces better quantitative scores when compared to the three existing methods.

  2. Local gray level S-curve transformation - A generalized contrast enhancement technique for medical images.

    Science.gov (United States)

    Gandhamal, Akash; Talbar, Sanjay; Gajre, Suhas; Hani, Ahmad Fadzil M; Kumar, Dileep

    2017-04-01

    Most medical images suffer from inadequate contrast and brightness, which leads to blurred or weak edges (low contrast) between adjacent tissues resulting in poor segmentation and errors in classification of tissues. Thus, contrast enhancement to improve visual information is extremely important in the development of computational approaches for obtaining quantitative measurements from medical images. In this research, a contrast enhancement algorithm that applies gray-level S-curve transformation technique locally in medical images obtained from various modalities is investigated. The S-curve transformation is an extended gray level transformation technique that results into a curve similar to a sigmoid function through a pixel to pixel transformation. This curve essentially increases the difference between minimum and maximum gray values and the image gradient, locally thereby, strengthening edges between adjacent tissues. The performance of the proposed technique is determined by measuring several parameters namely, edge content (improvement in image gradient), enhancement measure (degree of contrast enhancement), absolute mean brightness error (luminance distortion caused by the enhancement), and feature similarity index measure (preservation of the original image features). Based on medical image datasets comprising 1937 images from various modalities such as ultrasound, mammograms, fluorescent images, fundus, X-ray radiographs and MR images, it is found that the local gray-level S-curve transformation outperforms existing techniques in terms of improved contrast and brightness, resulting in clear and strong edges between adjacent tissues. The proposed technique can be used as a preprocessing tool for effective segmentation and classification of tissue structures in medical images. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. 3D shape recovery from image focus using gray level co-occurrence matrix

    Science.gov (United States)

    Mahmood, Fahad; Munir, Umair; Mehmood, Fahad; Iqbal, Javaid

    2018-04-01

    Recovering a precise and accurate 3-D shape of the target object utilizing robust 3-D shape recovery algorithm is an ultimate objective of computer vision community. Focus measure algorithm plays an important role in this architecture which convert the color values of each pixel of the acquired 2-D image dataset into corresponding focus values. After convolving the focus measure filter with the input 2-D image dataset, a 3-D shape recovery approach is applied which will recover the depth map. In this document, we are concerned with proposing Gray Level Co-occurrence Matrix along with its statistical features for computing the focus information of the image dataset. The Gray Level Co-occurrence Matrix quantifies the texture present in the image using statistical features and then applies joint probability distributive function of the gray level pairs of the input image. Finally, we quantify the focus value of the input image using Gaussian Mixture Model. Due to its little computational complexity, sharp focus measure curve, robust to random noise sources and accuracy, it is considered as superior alternative to most of recently proposed 3-D shape recovery approaches. This algorithm is deeply investigated on real image sequences and synthetic image dataset. The efficiency of the proposed scheme is also compared with the state of art 3-D shape recovery approaches. Finally, by means of two global statistical measures, root mean square error and correlation, we claim that this approach -in spite of simplicity generates accurate results.

  4. Hand Vein Images Enhancement Based on Local Gray-level Information Histogram

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2015-06-01

    Full Text Available Based on the Histogram equalization theory, this paper presents a novel concept of histogram to realize the contrast enhancement of hand vein images, avoiding the lost of topological vein structure or importing the fake vein information. Firstly, we propose the concept of gray-level information histogram, the fundamental characteristic of which is that the amplitudes of the components can objectively reflect the contribution of the gray levels and information to the representation of image information. Then, we propose the histogram equalization method that is composed of an automatic histogram separation module and an intensity transformation module, and the histogram separation module is a combination of the proposed prompt multiple threshold procedure and an optimum peak signal-to-noise (PSNR calculation to separate the histogram into small-scale detail, the use of the intensity transformation module can enhance the vein images with vein topological structure and gray information preservation for each generated sub-histogram. Experimental results show that the proposed method can achieve extremely good contrast enhancement effect.

  5. Automatic adjustment of display window (gray-level condition) for MR images using neural networks

    International Nuclear Information System (INIS)

    Ohhashi, Akinami; Nambu, Kyojiro.

    1992-01-01

    We have developed a system to automatically adjust the display window width and level (WWL) for MR images using neural networks. There were three main points in the development of our system as follows: 1) We defined an index for the clarity of a displayed image, and called 'EW'. EW is a quantitative measure of the clarity of an image displayed in a certain WWL, and can be derived from the difference between gray-level with the WWL adjusted by a human expert and with a certain WWL. 2) We extracted a group of six features from a gray-level histogram of a displayed image. We designed two neural networks which are able to learn the relationship between these features and the desired output (teaching signal), 'EQ', which is normalized to 0 to 1.0 from EW. Two neural networks were used to share the patterns to be learned; one learns a variety of patterns with less accuracy, and the other learns similar patterns with accuracy. Learning was performed using a back-propagation method. As a result, the neural networks after learning are able to provide a quantitative measure, 'Q', of the clarity of images displayed in the designated WWL. 3) Using the 'Hill climbing' method, we have been able to determine the best possible WWL for a displaying image. We have tested this technique for MR brain images. The results show that this system can adjust WWL comparable to that adjusted by a human expert for the majority of test images. The neural network is effective for the automatic adjustment of the display window for MR images. We are now studying the application of this method to MR images of another regions. (author)

  6. Histogram and gray level co-occurrence matrix on gray-scale ultrasound images for diagnosing lymphocytic thyroiditis.

    Science.gov (United States)

    Shin, Young Gyung; Yoo, Jaeheung; Kwon, Hyeong Ju; Hong, Jung Hwa; Lee, Hye Sun; Yoon, Jung Hyun; Kim, Eun-Kyung; Moon, Hee Jung; Han, Kyunghwa; Kwak, Jin Young

    2016-08-01

    The objective of the study was to evaluate whether texture analysis using histogram and gray level co-occurrence matrix (GLCM) parameters can help clinicians diagnose lymphocytic thyroiditis (LT) and differentiate LT according to pathologic grade. The background thyroid pathology of 441 patients was classified into no evidence of LT, chronic LT (CLT), and Hashimoto's thyroiditis (HT). Histogram and GLCM parameters were extracted from the regions of interest on ultrasound. The diagnostic performances of the parameters for diagnosing and differentiating LT were calculated. Of the histogram and GLCM parameters, the mean on histogram had the highest Az (0.63) and VUS (0.303). As the degrees of LT increased, the mean decreased and the standard deviation and entropy increased. The mean on histogram from gray-scale ultrasound showed the best diagnostic performance as a single parameter in differentiating LT according to pathologic grade as well as in diagnosing LT. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Reconstructing the CT number array from gray-level images and its application in PACS

    Science.gov (United States)

    Chen, Xu; Zhuang, Tian-ge; Wu, Wei

    2001-08-01

    Although DICOM compliant computed tomography has been prevailing in medical fields nowadays, there are some incompliant ones, from which we could hardly get the raw data and make an apropos interpretation due to the proprietary image format. Under such condition, one usually uses frame grabbers to capture CT images, the results of which could not be freely adjusted by radiologists as the original CT number array could. To alleviate the inflexibility, a new method is presented in this paper to reconstruct the array of CT number from several gray-level images acquired under different window settings. Its feasibility is investigated and a few tips are put forward to correct the errors caused respectively by 'Border Effect' and some hardware problems. The accuracy analysis proves it a good substitution for original CT number array acquisition. And this method has already been successfully used in our newly developing PACS and accepted by the radiologists in clinical use.

  8. Low gray scale values of computerized images of carotid plaques associated with increased levels of triglyceride-rich lipoproteins and with increased plaque lipid content

    DEFF Research Database (Denmark)

    Grønholdt, Marie-Louise M.; Nordestgaard, Børge; Weibe, Britt M.

    1997-01-01

    Relatioin between low gray scale values in computerized images of carotid plaques and 1) plasma levels of triglyceride-rich lipoproteins and 2) plaque lipid content......Relatioin between low gray scale values in computerized images of carotid plaques and 1) plasma levels of triglyceride-rich lipoproteins and 2) plaque lipid content...

  9. Determining the Number of Colors or Gray Levels in an Image Using Approximate Bayes Factors: The Pseudolikelihood Information Criterion (PLIC)

    National Research Council Canada - National Science Library

    Stanford, Derek C; Raftery, Adrian E

    2001-01-01

    .... This is motivated by medical and satellite image segmentation, and may also be useful for color and gray scale image quantization, the display and storage of computer-generated holograms, and the use...

  10. SD LMS L-Filters for Filtration of Gray Level Images in Timespatial Domain Based on GLCM Features

    Directory of Open Access Journals (Sweden)

    Robert Hudec

    2008-01-01

    Full Text Available In this paper, the new kind of adaptive signal-dependent LMS L-filter for suppression of a mixed noise in greyscale images is developed. It is based on the texture parameter measurement as modification of spatial impulse detector structure. Moreover, the one of GLCM (Gray Level Co-occurrence Matrix features, namely, the contrast or inertia adjusted by threshold as switch between partial filters is utilised. Finally, at the positions of partial filters the adaptive LMS versions of L-filters are chosen.

  11. Gender classification from face images by using local binary pattern and gray-level co-occurrence matrix

    Science.gov (United States)

    Uzbaş, Betül; Arslan, Ahmet

    2018-04-01

    Gender is an important step for human computer interactive processes and identification. Human face image is one of the important sources to determine gender. In the present study, gender classification is performed automatically from facial images. In order to classify gender, we propose a combination of features that have been extracted face, eye and lip regions by using a hybrid method of Local Binary Pattern and Gray-Level Co-Occurrence Matrix. The features have been extracted from automatically obtained face, eye and lip regions. All of the extracted features have been combined and given as input parameters to classification methods (Support Vector Machine, Artificial Neural Networks, Naive Bayes and k-Nearest Neighbor methods) for gender classification. The Nottingham Scan face database that consists of the frontal face images of 100 people (50 male and 50 female) is used for this purpose. As the result of the experimental studies, the highest success rate has been achieved as 98% by using Support Vector Machine. The experimental results illustrate the efficacy of our proposed method.

  12. An algorithm for automatic detection of chromosome aberrations induced by radiation using features of gray level profile across the main axis of chromosome image

    International Nuclear Information System (INIS)

    Kawashima, Hironao; Imai, Katsuhiro; Fukuoka, Hideya; Yamamoto, Mikio; Hayata, Isamu.

    1990-01-01

    A simple algorithm for detecting chromosome aberrations induced by radiation is developed. Microscopic images of conventional Giemsa stained chromosomes of rearranged chromosomes (abnormal chromosomes) including dicentric chromosomes, ordinary acentric fragments, small acentric fragments, and acentric rings are used as samples. Variation of width along the main axis and gray level profile across the main axis of the chromosome image are used as features for classification. In 7 microscopic images which include 257 single chromosomes, 90.0% (231 chromosomes) are correctly classified into 6 categories and 23 of 26 abnormal chromosomes are correctly identified. As a result of discrimination between a normal and an abnormal chromosome, 95.3% of abnormal chromosomes are detected. (author)

  13. Computed gray levels in multislice and cone-beam computed tomography.

    Science.gov (United States)

    Azeredo, Fabiane; de Menezes, Luciane Macedo; Enciso, Reyes; Weissheimer, Andre; de Oliveira, Rogério Belle

    2013-07-01

    Gray level is the range of shades of gray in the pixels, representing the x-ray attenuation coefficient that allows for tissue density assessments in computed tomography (CT). An in-vitro study was performed to investigate the relationship between computed gray levels in 3 cone-beam CT (CBCT) scanners and 1 multislice spiral CT device using 5 software programs. Six materials (air, water, wax, acrylic, plaster, and gutta-percha) were scanned with the CBCT and CT scanners, and the computed gray levels for each material at predetermined points were measured with OsiriX Medical Imaging software (Geneva, Switzerland), OnDemand3D (CyberMed International, Seoul, Korea), E-Film (Merge Healthcare, Milwaukee, Wis), Dolphin Imaging (Dolphin Imaging & Management Solutions, Chatsworth, Calif), and InVivo Dental Software (Anatomage, San Jose, Calif). The repeatability of these measurements was calculated with intraclass correlation coefficients, and the gray levels were averaged to represent each material. Repeated analysis of variance tests were used to assess the differences in gray levels among scanners and materials. There were no differences in mean gray levels with the different software programs. There were significant differences in gray levels between scanners for each material evaluated (P <0.001). The software programs were reliable and had no influence on the CT and CBCT gray level measurements. However, the gray levels might have discrepancies when different CT and CBCT scanners are used. Therefore, caution is essential when interpreting or evaluating CBCT images because of the significant differences in gray levels between different CBCT scanners, and between CBCT and CT values. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  14. Optimal voxel size for measuring global gray and white matter proton metabolite concentrations using chemical shift imaging

    DEFF Research Database (Denmark)

    Hanson, Lars Peter Grüner; Adalsteinsson, E; Pfefferbaum, A

    2000-01-01

    Quantification of gray and white matter levels of spectroscopically visible metabolites can provide important insights into brain development and pathological conditions. Chemical shift imaging offers a gain in efficiency for estimation of global gray and white matter metabolite concentrations co...

  15. Retrospective analysis of cytopathology using gray level co-occurrence matrix algorithm for thyroid malignant nodules in the ultrasound imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeong Ju; Lee, Jin Soo [Dept. of Radiology, Inje University Haeundae Paik Hospital, Busan (Korea, Republic of); Kang, Se Sik; Kim, Chang Soo [Dept. of Radiological Science, College of Health Sciences, Catholic University of Pusan, Busan (Korea, Republic of)

    2017-06-15

    This study evaluated the applicability of computer-aided diagnosis by retrospective analysis of GLCM algorithm based on cytopathological diagnosis of normal and malignant nodules in thyroid ultrasound images. In the experiment, the recognition rate and ROC curve of thyroid malignant nodule were analyzed using 6 parameters of GLCM algorithm. Experimental results showed 97% energy, 93% contrast, 92% correlation, 92% homogeneity, 100% entropy and 100% variance. Statistical analysis showed that the area under the curve of each parameter was more than 0.947 (p = 0 .001) in t he ROC curve, which was s ignificant in the recognition of thyroid malignant nodules. In the GLCM, the cut-off value of each parameter can be used to predict the disease through analysis of quantitative computer-aided diagnosis.

  16. Non-invasive Estimation of Temperature during Physiotherapeutic Ultrasound Application Using the Average Gray-Level Content of B-Mode Images: A Metrological Approach.

    Science.gov (United States)

    Alvarenga, André V; Wilkens, Volker; Georg, Olga; Costa-Félix, Rodrigo P B

    2017-09-01

    Healing therapies that make use of ultrasound are based on raising the temperature in biological tissue. However, it is not possible to heal impaired tissue by applying a high dose of ultrasound. The temperature of the tissue is ultimately the physical quantity that has to be assessed to minimize the risk of undesired injury. Invasive temperature measurement techniques are easy to use, despite the fact that they are detrimental to human well being. Another approach to assessing a rise in tissue temperature is to derive the material's general response to temperature variations from ultrasonic parameters. In this article, a method for evaluating temperature variations is described. The method is based on the analytical study of an ultrasonic image, in which gray-level variations are correlated to the temperature variations in a tissue-mimicking material. The physical assumption is that temperature variations induce wave propagation changes modifying the backscattered ultrasound signal, which are expressed in the ultrasonographic images. For a temperature variation of about 15°C, the expanded uncertainty for a coverage probability of 0.95 was found to be 2.5°C in the heating regime and 1.9°C in the cooling regime. It is possible to use the model proposed in this article in a straightforward manner to monitor temperature variation during a physiotherapeutic ultrasound application, provided the tissue-mimicking material approach is transferred to actual biological tissue. The novelty of such approach resides in the metrology-based investigation outlined here, as well as in its ease of reproducibility. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  17. MR imaging of heterotopic gray matter

    International Nuclear Information System (INIS)

    Kryst-Widzgowska, T.; Kozlowski, P.; Poniatowska, R.

    1994-01-01

    Six patients with heterotopic gray matter were evaluated with MR. 5 patients had history of seizures. 4 cases were suspected of the cerebral tumor. In the MR examination areas of heterotopic gray matter were found along the posterior horn of the lateral ventricle on the one side in 4 cases and bilateraly in 2 cases. In 3 cases another brain abnormalities were also detected including: hypoplasia of corpus callosum, hypoplasia of brain hemisphere, cavum septi pellucidi. MR is a modality of choice in the assessment of abnormal gray matter migration. (author)

  18. Blood oxygen level-dependent magnetic resonance imaging for detecting pathological patterns in patients with lupus nephritis: a preliminary study using gray-level co-occurrence matrix analysis.

    Science.gov (United States)

    Shi, Huilan; Jia, Junya; Li, Dong; Wei, Li; Shang, Wenya; Zheng, Zhenfeng

    2018-01-01

    Objective Blood oxygen level-dependent magnetic resonance imaging (BOLD MRI) is a noninvasive technique useful in patients with renal disease. The current study was performed to determine whether BOLD MRI can contribute to the diagnosis of renal pathological patterns. Methods BOLD MRI was used to obtain functional magnetic resonance parameter R2* values. Gray-level co-occurrence matrixes (GLCMs) were generated for gray-scale maps. Several GLCM parameters were calculated and used to construct algorithmic models for renal pathological patterns. Results Histopathology and BOLD MRI were used to examine 12 patients. Two GLCM parameters, including correlation and energy, revealed differences among four groups of renal pathological patterns. Four Fisher's linear discriminant formulas were constructed using two variables, including the correlation at 45° and correlation at 90°. A cross-validation test showed that the formulas correctly predicted 28 of 36 samples, and the rate of correct prediction was 77.8%. Conclusions Differences in the texture characteristics of BOLD MRI in patients with lupus nephritis may be detected by GLCM analysis. Discriminant formulas constructed using GLCM parameters may facilitate prediction of renal pathological patterns.

  19. Parallel implementation of Gray Level Co-occurrence Matrices and Haralick texture features on cell architecture

    NARCIS (Netherlands)

    Shahbahrami, A.; Pham, T.A.; Bertels, K.L.M.

    2011-01-01

    Texture features extraction algorithms are key functions in various image processing applications such as medical images, remote sensing, and content-based image retrieval. The most common way to extract texture features is the use of Gray Level Co-occurrence Matrices (GLCMs). The GLCM contains the

  20. MIA - a free and open source software for gray scale medical image analysis

    OpenAIRE

    Wöllny, Gert; Kellman, Peter; Ledesma Carbayo, María Jesús; Skinner, Matthew M.; Hublin, Jean-Jaques; Hierl, Thomas

    2013-01-01

    Background Gray scale images make the bulk of data in bio-medical image analysis, and hence, the main focus of many image processing tasks lies in the processing of these monochrome images. With ever improving acquisition devices, spatial and temporal image resolution increases, and data sets become very large. Various image processing frameworks exists that make the development of new algorithms easy by using high level programming languages or visual programming. These frameworks are also a...

  1. Histogram-based adaptive gray level scaling for texture feature classification of colorectal polyps

    Science.gov (United States)

    Pomeroy, Marc; Lu, Hongbing; Pickhardt, Perry J.; Liang, Zhengrong

    2018-02-01

    Texture features have played an ever increasing role in computer aided detection (CADe) and diagnosis (CADx) methods since their inception. Texture features are often used as a method of false positive reduction for CADe packages, especially for detecting colorectal polyps and distinguishing them from falsely tagged residual stool and healthy colon wall folds. While texture features have shown great success there, the performance of texture features for CADx have lagged behind primarily because of the more similar features among different polyps types. In this paper, we present an adaptive gray level scaling and compare it to the conventional equal-spacing of gray level bins. We use a dataset taken from computed tomography colonography patients, with 392 polyp regions of interest (ROIs) identified and have a confirmed diagnosis through pathology. Using the histogram information from the entire ROI dataset, we generate the gray level bins such that each bin contains roughly the same number of voxels Each image ROI is the scaled down to two different numbers of gray levels, using both an equal spacing of Hounsfield units for each bin, and our adaptive method. We compute a set of texture features from the scaled images including 30 gray level co-occurrence matrix (GLCM) features and 11 gray level run length matrix (GLRLM) features. Using a random forest classifier to distinguish between hyperplastic polyps and all others (adenomas and adenocarcinomas), we find that the adaptive gray level scaling can improve performance based on the area under the receiver operating characteristic curve by up to 4.6%.

  2. Differences in quantitative assessment of myocardial scar and gray zone by LGE-CMR imaging using established gray zone protocols.

    Science.gov (United States)

    Mesubi, Olurotimi; Ego-Osuala, Kelechi; Jeudy, Jean; Purtilo, James; Synowski, Stephen; Abutaleb, Ameer; Niekoop, Michelle; Abdulghani, Mohammed; Asoglu, Ramazan; See, Vincent; Saliaris, Anastasios; Shorofsky, Stephen; Dickfeld, Timm

    2015-02-01

    Late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) imaging is the gold standard for myocardial scar evaluation. Heterogeneous areas of scar ('gray zone'), may serve as arrhythmogenic substrate. Various gray zone protocols have been correlated to clinical outcomes and ventricular tachycardia channels. This study assessed the quantitative differences in gray zone and scar core sizes as defined by previously validated signal intensity (SI) threshold algorithms. High quality LGE-CMR images performed in 41 cardiomyopathy patients [ischemic (33) or non-ischemic (8)] were analyzed using previously validated SI threshold methods [Full Width at Half Maximum (FWHM), n-standard deviation (NSD) and modified-FWHM]. Myocardial scar was defined as scar core and gray zone using SI thresholds based on these methods. Scar core, gray zone and total scar sizes were then computed and compared among these models. The median gray zone mass was 2-3 times larger with FWHM (15 g, IQR: 8-26 g) compared to NSD or modified-FWHM (5 g, IQR: 3-9 g; and 8 g. IQR: 6-12 g respectively, p zone extent (percentage of total scar that was gray zone) also varied significantly among the three methods, 51 % (IQR: 42-61 %), 17 % (IQR: 11-21 %) versus 38 % (IQR: 33-43 %) for FWHM, NSD and modified-FWHM respectively (p zone and scar core. Infarct core and total myocardial scar mass also differ using these methods. Further evaluation of the most accurate quantification method is needed.

  3. Patient dose, gray level and exposure index with a computed radiography system

    Science.gov (United States)

    Silva, T. R.; Yoshimura, E. M.

    2014-02-01

    Computed radiography (CR) is gradually replacing conventional screen-film system in Brazil. To assess image quality, manufactures provide the calculation of an exposure index through the acquisition software of the CR system. The objective of this study is to verify if the CR image can be used as an evaluator of patient absorbed dose too, through a relationship between the entrance skin dose and the exposure index or the gray level values obtained in the image. The CR system used for this study (Agfa model 30-X with NX acquisition software) calculates an exposure index called Log of the Median (lgM), related to the absorbed dose to the IP. The lgM value depends on the average gray level (called Scan Average Level (SAL)) of the segmented pixel value histogram of the whole image. A Rando male phantom was used to simulate a human body (chest and head), and was irradiated with an X-ray equipment, using usual radiologic techniques for chest exams. Thermoluminescent dosimeters (LiF, TLD100) were used to evaluate entrance skin dose and exit dose. The results showed a logarithm relation between entrance dose and SAL in the image center, regardless of the beam filtration. The exposure index varies linearly with the entrance dose, but the angular coefficient is beam quality dependent. We conclude that, with an adequate calibration, the CR system can be used to evaluate the patient absorbed dose.

  4. Fuzzy Matching Based on Gray-scale Difference for Quantum Images

    Science.gov (United States)

    Luo, GaoFeng; Zhou, Ri-Gui; Liu, XingAo; Hu, WenWen; Luo, Jia

    2018-05-01

    Quantum image processing has recently emerged as an essential problem in practical tasks, e.g. real-time image matching. Previous studies have shown that the superposition and entanglement of quantum can greatly improve the efficiency of complex image processing. In this paper, a fuzzy quantum image matching scheme based on gray-scale difference is proposed to find out the target region in a reference image, which is very similar to the template image. Firstly, we employ the proposed enhanced quantum representation (NEQR) to store digital images. Then some certain quantum operations are used to evaluate the gray-scale difference between two quantum images by thresholding. If all of the obtained gray-scale differences are not greater than the threshold value, it indicates a successful fuzzy matching of quantum images. Theoretical analysis and experiments show that the proposed scheme performs fuzzy matching at a low cost and also enables exponentially significant speedup via quantum parallel computation.

  5. Efficiency of quantitative echogenicity for investigating supraspinatus tendinopathy by the gray-level histogram of two ultrasound devices.

    Science.gov (United States)

    Hsu, Jiun-Cheng; Chen, Po-Han; Huang, Kuo-Chin; Tsai, Yao-Hung; Hsu, Wei-Hsiu

    2017-10-01

    The gray-level histogram of ultrasound is a promising tool for scanning the hypoechogenic appearance of supraspinatus tendinopathy, and the aim of this study was to test the hypothesis that the gray-level value of the supraspinatus tendon in the painful shoulder has a lower value on B-mode images even though in different ultrasound devices. Sixty-seven patients who had unilateral shoulder pain with rotator cuff tendinopathy underwent bilateral shoulder ultrasonography, and we compared the mean gray-level values of painful shoulders and contralateral shoulders without any pain in each patient using two ultrasound devices. The echogenicity ratio (symptomatic/asymptomatic side) of two ultrasound devices was compared. A significant difference existed between the symptomatic shoulder and contralateral asymptomatic shoulder (p level value measurements of each device. The symptomatic-to-asymptomatic tendon echogenicity ratio of device A was 0.919 ± 0.090 in the transverse plane and 0.937 ± 0.081 in the longitudinal plane, and the echogenicity ratio of device B was 0.899 ± 0.113 in the transverse plane and 0.940 ± 0.113 in the longitudinal plane. The decline of the mean gray-level value and the echogenicity ratio of the supraspinatus tendon in the painful shoulder may be utilized as a useful sonographic reference of unilateral rotator cuff lesions. Diagnostic level III.

  6. Improving the Calibration of Image Sensors Based on IOFBs, Using Differential Gray-Code Space Encoding

    Directory of Open Access Journals (Sweden)

    Carlos Luna Vázquez

    2012-07-01

    Full Text Available This paper presents a fast calibration method to determine the transfer function for spatial correspondences in image transmission devices with Incoherent Optical Fiber Bundles (IOFBs, by performing a scan of the input, using differential patterns generated from a Gray code (Differential Gray-Code Space Encoding, DGSE. The results demonstrate that this technique provides a noticeable reduction in processing time and better quality of the reconstructed image compared to other, previously employed techniques, such as point or fringe scanning, or even other known space encoding techniques.

  7. A Parallel Algorithm for Connected Component Labelling of Gray-scale Images on Homogeneous Multicore Architectures

    International Nuclear Information System (INIS)

    Niknam, Mehdi; Thulasiraman, Parimala; Camorlinga, Sergio

    2010-01-01

    Connected component labelling is an essential step in image processing. We provide a parallel version of Suzuki's sequential connected component algorithm in order to speed up the labelling process. Also, we modify the algorithm to enable labelling gray-scale images. Due to the data dependencies in the algorithm we used a method similar to pipeline to exploit parallelism. The parallel algorithm method achieved a speedup of 2.5 for image size of 256 x 256 pixels using 4 processing threads.

  8. Diffusion-tensor MR imaging of gray and white matter development during normal human brain maturation.

    Science.gov (United States)

    Mukherjee, Pratik; Miller, Jeffrey H; Shimony, Joshua S; Philip, Joseph V; Nehra, Deepika; Snyder, Abraham Z; Conturo, Thomas E; Neil, Jeffrey J; McKinstry, Robert C

    2002-10-01

    Conventional MR imaging findings of human brain development are thought to result from decreasing water content, increasing macromolecular concentration, and myelination. We use diffusion-tensor MR imaging to test theoretical models that incorporate hypotheses regarding how these maturational processes influence water diffusion in developing gray and white matter. Experimental data were derived from diffusion-tensor imaging of 167 participants, ages 31 gestational weeks to 11 postnatal years. An isotropic diffusion model was applied to the gray matter of the basal ganglia and thalamus. A model that assumes changes in the magnitude of diffusion while maintaining cylindrically symmetric anisotropy was applied to the white matter of the corpus callosum and internal capsule. Deviations of the diffusion tensor from the ideal model predictions, due to measurement noise, were estimated by using Monte Carlo simulations. Developing gray matter of the basal ganglia and developing white matter of the internal capsule and corpus callosum largely conformed to theory, with only small departures from model predictions in older children. However, data from the thalamus substantially diverged from predicted values, with progressively larger deviations from the model with increasing participant age. Changes in water diffusion during maturation of central gray and white matter structures can largely be explained by theoretical models incorporating simple assumptions regarding the influence of brain water content and myelination, although deviations from theory increase as the brain matures. Diffusion-tensor MR imaging is a powerful method for studying the process of brain development, with both scientific and clinical applications.

  9. THE MEASUREMENT OF BONE QUALITY USING GRAY LEVEL CO-OCCURRENCE MATRIX TEXTURAL FEATURES.

    Science.gov (United States)

    Shirvaikar, Mukul; Huang, Ning; Dong, Xuanliang Neil

    2016-10-01

    In this paper, statistical methods for the estimation of bone quality to predict the risk of fracture are reported. Bone mineral density and bone architecture properties are the main contributors of bone quality. Dual-energy X-ray Absorptiometry (DXA) is the traditional clinical measurement technique for bone mineral density, but does not include architectural information to enhance the prediction of bone fragility. Other modalities are not practical due to cost and access considerations. This study investigates statistical parameters based on the Gray Level Co-occurrence Matrix (GLCM) extracted from two-dimensional projection images and explores links with architectural properties and bone mechanics. Data analysis was conducted on Micro-CT images of 13 trabecular bones (with an in-plane spatial resolution of about 50μm). Ground truth data for bone volume fraction (BV/TV), bone strength and modulus were available based on complex 3D analysis and mechanical tests. Correlation between the statistical parameters and biomechanical test results was studied using regression analysis. The results showed Cluster-Shade was strongly correlated with the microarchitecture of the trabecular bone and related to mechanical properties. Once the principle thesis of utilizing second-order statistics is established, it can be extended to other modalities, providing cost and convenience advantages for patients and doctors.

  10. MIA - A free and open source software for gray scale medical image analysis.

    Science.gov (United States)

    Wollny, Gert; Kellman, Peter; Ledesma-Carbayo, María-Jesus; Skinner, Matthew M; Hublin, Jean-Jaques; Hierl, Thomas

    2013-10-11

    Gray scale images make the bulk of data in bio-medical image analysis, and hence, the main focus of many image processing tasks lies in the processing of these monochrome images. With ever improving acquisition devices, spatial and temporal image resolution increases, and data sets become very large.Various image processing frameworks exists that make the development of new algorithms easy by using high level programming languages or visual programming. These frameworks are also accessable to researchers that have no background or little in software development because they take care of otherwise complex tasks. Specifically, the management of working memory is taken care of automatically, usually at the price of requiring more it. As a result, processing large data sets with these tools becomes increasingly difficult on work station class computers.One alternative to using these high level processing tools is the development of new algorithms in a languages like C++, that gives the developer full control over how memory is handled, but the resulting workflow for the prototyping of new algorithms is rather time intensive, and also not appropriate for a researcher with little or no knowledge in software development.Another alternative is in using command line tools that run image processing tasks, use the hard disk to store intermediate results, and provide automation by using shell scripts. Although not as convenient as, e.g. visual programming, this approach is still accessable to researchers without a background in computer science. However, only few tools exist that provide this kind of processing interface, they are usually quite task specific, and don't provide an clear approach when one wants to shape a new command line tool from a prototype shell script. The proposed framework, MIA, provides a combination of command line tools, plug-ins, and libraries that make it possible to run image processing tasks interactively in a command shell and to prototype by

  11. Multifractal analysis of 2D gray soil images

    Science.gov (United States)

    González-Torres, Ivan; Losada, Juan Carlos; Heck, Richard; Tarquis, Ana M.

    2015-04-01

    Soil structure, understood as the spatial arrangement of soil pores, is one of the key factors in soil modelling processes. Geometric properties of individual and interpretation of the morphological parameters of pores can be estimated from thin sections or 3D Computed Tomography images (Tarquis et al., 2003), but there is no satisfactory method to binarized these images and quantify the complexity of their spatial arrangement (Tarquis et al., 2008, Tarquis et al., 2009; Baveye et al., 2010). The objective of this work was to apply a multifractal technique, their singularities (α) and f(α) spectra, to quantify it without applying any threshold (Gónzalez-Torres, 2014). Intact soil samples were collected from four horizons of an Argisol, formed on the Tertiary Barreiras group of formations in Pernambuco state, Brazil (Itapirema Experimental Station). The natural vegetation of the region is tropical, coastal rainforest. From each horizon, showing different porosities and spatial arrangements, three adjacent samples were taken having a set of twelve samples. The intact soil samples were imaged using an EVS (now GE Medical. London, Canada) MS-8 MicroCT scanner with 45 μm pixel-1 resolution (256x256 pixels). Though some samples required paring to fit the 64 mm diameter imaging tubes, field orientation was maintained. References Baveye, P.C., M. Laba, W. Otten, L. Bouckaert, P. Dello, R.R. Goswami, D. Grinev, A. Houston, Yaoping Hu, Jianli Liu, S. Mooney, R. Pajor, S. Sleutel, A. Tarquis, Wei Wang, Qiao Wei, Mehmet Sezgin. Observer-dependent variability of the thresholding step in the quantitative analysis of soil images and X-ray microtomography data. Geoderma, 157, 51-63, 2010. González-Torres, Iván. Theory and application of multifractal analysis methods in images for the study of soil structure. Master thesis, UPM, 2014. Tarquis, A.M., R.J. Heck, J.B. Grau; J. Fabregat, M.E. Sanchez and J.M. Antón. Influence of Thresholding in Mass and Entropy Dimension of 3-D

  12. Material microstructures analyzed by using gray level Co-occurrence matrices

    International Nuclear Information System (INIS)

    Hu Yansu; Wang Zhijun; Fan Xiaoguang; Li Junjie; Gao Ang

    2017-01-01

    The mechanical properties of materials greatly depend on the microstructure morphology. The quantitative characterization of material microstructures is essential for the performance prediction and hence the material design. At present, the quantitative characterization methods mainly rely on the microstructure characterization of shape, size, distribution, and volume fraction, which related to the mechanical properties. These traditional methods have been applied for several decades and the subjectivity of human factors induces unavoidable errors. In this paper, we try to bypass the traditional operations and identify the relationship between the microstructures and the material properties by the texture of image itself directly. The statistical approach is based on gray level Co-occurrence matrix (GLCM), allowing an objective and repeatable study on material microstructures. We first present how to identify GLCM with the optimal parameters, and then apply the method on three systems with different microstructures. The results show that GLCM can reveal the interface information and microstructures complexity with less human impact. Naturally, there is a good correlation between GLCM and the mechanical properties. (paper)

  13. Reproducibility of F18-FDG PET radiomic features for different cervical tumor segmentation methods, gray-level discretization, and reconstruction algorithms.

    Science.gov (United States)

    Altazi, Baderaldeen A; Zhang, Geoffrey G; Fernandez, Daniel C; Montejo, Michael E; Hunt, Dylan; Werner, Joan; Biagioli, Matthew C; Moros, Eduardo G

    2017-11-01

    Site-specific investigations of the role of radiomics in cancer diagnosis and therapy are emerging. We evaluated the reproducibility of radiomic features extracted from 18 Flourine-fluorodeoxyglucose ( 18 F-FDG) PET images for three parameters: manual versus computer-aided segmentation methods, gray-level discretization, and PET image reconstruction algorithms. Our cohort consisted of pretreatment PET/CT scans from 88 cervical cancer patients. Two board-certified radiation oncologists manually segmented the metabolic tumor volume (MTV 1 and MTV 2 ) for each patient. For comparison, we used a graphical-based method to generate semiautomated segmented volumes (GBSV). To address any perturbations in radiomic feature values, we down-sampled the tumor volumes into three gray-levels: 32, 64, and 128 from the original gray-level of 256. Finally, we analyzed the effect on radiomic features on PET images of eight patients due to four PET 3D-reconstruction algorithms: maximum likelihood-ordered subset expectation maximization (OSEM) iterative reconstruction (IR) method, fourier rebinning-ML-OSEM (FOREIR), FORE-filtered back projection (FOREFBP), and 3D-Reprojection (3DRP) analytical method. We extracted 79 features from all segmentation method, gray-levels of down-sampled volumes, and PET reconstruction algorithms. The features were extracted using gray-level co-occurrence matrices (GLCM), gray-level size zone matrices (GLSZM), gray-level run-length matrices (GLRLM), neighborhood gray-tone difference matrices (NGTDM), shape-based features (SF), and intensity histogram features (IHF). We computed the Dice coefficient between each MTV and GBSV to measure segmentation accuracy. Coefficient values close to one indicate high agreement, and values close to zero indicate low agreement. We evaluated the effect on radiomic features by calculating the mean percentage differences (d¯) between feature values measured from each pair of parameter elements (i.e. segmentation methods: MTV

  14. A novel quantum LSB-based steganography method using the Gray code for colored quantum images

    Science.gov (United States)

    Heidari, Shahrokh; Farzadnia, Ehsan

    2017-10-01

    As one of the prevalent data-hiding techniques, steganography is defined as the act of concealing secret information in a cover multimedia encompassing text, image, video and audio, imperceptibly, in order to perform interaction between the sender and the receiver in which nobody except the receiver can figure out the secret data. In this approach a quantum LSB-based steganography method utilizing the Gray code for quantum RGB images is investigated. This method uses the Gray code to accommodate two secret qubits in 3 LSBs of each pixel simultaneously according to reference tables. Experimental consequences which are analyzed in MATLAB environment, exhibit that the present schema shows good performance and also it is more secure and applicable than the previous one currently found in the literature.

  15. The FBI wavelet/scalar quantization standard for gray-scale fingerprint image compression

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, J.N.; Brislawn, C.M. [Los Alamos National Lab., NM (United States); Hopper, T. [Federal Bureau of Investigation, Washington, DC (United States)

    1993-05-01

    The FBI has recently adopted a standard for the compression of digitized 8-bit gray-scale fingerprint images. The standard is based on scalar quantization of a 64-subband discrete wavelet transform decomposition of the images, followed by Huffman coding. Novel features of the algorithm include the use of symmetric boundary conditions for transforming finite-length signals and a subband decomposition tailored for fingerprint images scanned at 500 dpi. The standard is intended for use in conjunction with ANSI/NBS-CLS 1-1993, American National Standard Data Format for the Interchange of Fingerprint Information, and the FBI`s Integrated Automated Fingerprint Identification System.

  16. The FBI wavelet/scalar quantization standard for gray-scale fingerprint image compression

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, J.N.; Brislawn, C.M. (Los Alamos National Lab., NM (United States)); Hopper, T. (Federal Bureau of Investigation, Washington, DC (United States))

    1993-01-01

    The FBI has recently adopted a standard for the compression of digitized 8-bit gray-scale fingerprint images. The standard is based on scalar quantization of a 64-subband discrete wavelet transform decomposition of the images, followed by Huffman coding. Novel features of the algorithm include the use of symmetric boundary conditions for transforming finite-length signals and a subband decomposition tailored for fingerprint images scanned at 500 dpi. The standard is intended for use in conjunction with ANSI/NBS-CLS 1-1993, American National Standard Data Format for the Interchange of Fingerprint Information, and the FBI's Integrated Automated Fingerprint Identification System.

  17. QR code based noise-free optical encryption and decryption of a gray scale image

    Science.gov (United States)

    Jiao, Shuming; Zou, Wenbin; Li, Xia

    2017-03-01

    In optical encryption systems, speckle noise is one major challenge in obtaining high quality decrypted images. This problem can be addressed by employing a QR code based noise-free scheme. Previous works have been conducted for optically encrypting a few characters or a short expression employing QR codes. This paper proposes a practical scheme for optically encrypting and decrypting a gray-scale image based on QR codes for the first time. The proposed scheme is compatible with common QR code generators and readers. Numerical simulation results reveal the proposed method can encrypt and decrypt an input image correctly.

  18. Automated gray level index measurements reveal only minor cytoarchitectonic changes of Brodmann area 9 in schizophrenia.

    Science.gov (United States)

    Tepest, Ralf; Vogeley, Kai; Viebahn, Bettina; Schneider-Axmann, Thomas; Honer, William G; Falkai, Peter

    2008-07-15

    Using an automatized gray level index (GLI) method, we recently found cytoarchitectonic abnormalities in schizophrenia in Brodmann area 10 (BA10) [Vogeley, K., Tepest, R., Schneider-Axmann, T., Hutte, H., Zilles, K., Honer, W.G., Falkai, P., 2003. Automated image analysis of disturbed cytoarchitecture in Brodmann area 10 in schizophrenia, Schizophrenia Research 62, 133-140]. As another potential key region involved in the pathophysiology of schizophrenia, we have now investigated BA9 in the same sample consisting of 20 schizophrenic cases and 20 controls. The GLI value represents the area-percentage covered by perikarya in measuring fields of microscopic images. BA9 was analyzed with respect to the factors diagnosis and gender for six different compartments approximately corresponding to the neocortical layers. The main result in BA9 was a significant interaction of diagnosis and gender for GLI in layers IV and V on the left side. Subsequent analyses separately performed concerning gender revealed a significant GLI increase in layer V on the left side in male patients compared with controls. However, after an adjustment of error probabilities for multiple testing, differences did not reach significance. No GLI difference was observed in the sample between diagnostic groups for females and between the diagnostic groups in general. Comparisons with our BA10 results suggest that cytoarchitectural changes relevant to schizophrenia appear different in various Brodmann areas. Since increases in GLI were found only in selected layers (V and VI) of BA9, these findings do not support a generalized neuropil reduction across all cortical layers.

  19. LSB-based Steganography Using Reflected Gray Code for Color Quantum Images

    Science.gov (United States)

    Li, Panchi; Lu, Aiping

    2018-02-01

    At present, the classical least-significant-bit (LSB) based image steganography has been extended to quantum image processing. For the existing LSB-based quantum image steganography schemes, the embedding capacity is no more than 3 bits per pixel. Therefore, it is meaningful to study how to improve the embedding capacity of quantum image steganography. This work presents a novel LSB-based steganography using reflected Gray code for colored quantum images, and the embedding capacity of this scheme is up to 4 bits per pixel. In proposed scheme, the secret qubit sequence is considered as a sequence of 4-bit segments. For the four bits in each segment, the first bit is embedded in the second LSB of B channel of the cover image, and and the remaining three bits are embedded in LSB of RGB channels of each color pixel simultaneously using reflected-Gray code to determine the embedded bit from secret information. Following the transforming rule, the LSB of stego-image are not always same as the secret bits and the differences are up to almost 50%. Experimental results confirm that the proposed scheme shows good performance and outperforms the previous ones currently found in the literature in terms of embedding capacity.

  20. Comparison of 12-bit and 8-bit gray scale resolution in MR imaging of the CNS

    International Nuclear Information System (INIS)

    Smith, H.J.; Bakke, S.J.; Smevik, B.; Hald, J.K.; Moen, G.; Rudenhed, B.; Abildgaard, A.

    1992-01-01

    A reduction in gray scale resolution of digital images from 12 to 8 bits per pixel usually means halving the storage space needed for the images. Theoretically, important diagnostic information may be lost in the process. We compared the sensitivity and specificity achieved by 4 radiologists in reading laser-printed films of original 12-bit MR images and cathode ray tube displays of the same images which had been compressed to 8 bits per pixel using a specially developed computer program. Receiver operating characteristics (ROC) curves showed no significant differences between film reading and screen reading. A paired 2-tailed t-test, applied on the data for actually positive cases, showed that the combined, average performance of the reviewers was significantly better at screen reading than at film reading. No such differences were found for actually negative cases. Some individual differences were found, but it is concluded that gray scale resolution of MR images may be reduced from 12 to 8 bits per pixel without any significant reduction in diagnostic information. (orig.)

  1. A Simple and Robust Gray Image Encryption Scheme Using Chaotic Logistic Map and Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Adelaïde Nicole Kengnou Telem

    2014-01-01

    Full Text Available A robust gray image encryption scheme using chaotic logistic map and artificial neural network (ANN is introduced. In the proposed method, an external secret key is used to derive the initial conditions for the logistic chaotic maps which are employed to generate weights and biases matrices of the multilayer perceptron (MLP. During the learning process with the backpropagation algorithm, ANN determines the weight matrix of the connections. The plain image is divided into four subimages which are used for the first diffusion stage. The subimages obtained previously are divided into the square subimage blocks. In the next stage, different initial conditions are employed to generate a key stream which will be used for permutation and diffusion of the subimage blocks. Some security analyses such as entropy analysis, statistical analysis, and key sensitivity analysis are given to demonstrate the key space of the proposed algorithm which is large enough to make brute force attacks infeasible. Computing validation using experimental data with several gray images has been carried out with detailed numerical analysis, in order to validate the high security of the proposed encryption scheme.

  2. Imaging the functional connectivity of the Periaqueductal Gray during genuine and sham electroacupuncture treatment

    Directory of Open Access Journals (Sweden)

    Tu Peichi

    2010-11-01

    Full Text Available Abstract Background Electroacupuncture (EA is currently one of the most popular acupuncture modalities. However, the continuous stimulation characteristic of EA treatment presents challenges to the use of conventional functional Magnetic Resonance Imaging (fMRI approaches for the investigation of neural mechanisms mediating treatment response because of the requirement for brief and intermittent stimuli in event related or block designed task paradigms. A relatively new analysis method, functional connectivity fMRI (fcMRI, has great potential for studying continuous treatment modalities such as EA. In a previous study, we found that, compared with sham acupuncture, EA can significantly reduce Periaqueductal Gray (PAG activity when subsequently evoked by experimental pain. Given the PAG's important role in mediating acupuncture analgesia, in this study we investigated functional connectivity with the area of the PAG we previously identified and how that connectivity was affected by genuine and sham EA. Results Forty-eight subjects, who were randomly assigned to receive either genuine or sham EA paired with either a high or low expectancy manipulation, completed the study. Direct comparison of each treatment mode's functional connectivity revealed: significantly greater connectivity between the PAG, left posterior cingulate cortex (PCC, and precuneus for the contrast of genuine minus sham; significantly greater connectivity between the PAG and right anterior insula for the contrast of sham minus genuine; no significant differences in connectivity between different contrasts of the two expectancy levels. Conclusions Our findings indicate the intrinsic functional connectivity changes among key brain regions in the pain matrix and default mode network during genuine EA compared with sham EA. We speculate that continuous genuine EA stimulation can modify the coupling of spontaneous activity in brain regions that play a role in modulating pain

  3. Illuminant direction estimation for a single image based on local region complexity analysis and average gray value.

    Science.gov (United States)

    Yi, Jizheng; Mao, Xia; Chen, Lijiang; Xue, Yuli; Compare, Angelo

    2014-01-10

    Illuminant direction estimation is an important research issue in the field of image processing. Due to low cost for getting texture information from a single image, it is worthwhile to estimate illuminant direction by employing scenario texture information. This paper proposes a novel computation method to estimate illuminant direction on both color outdoor images and the extended Yale face database B. In our paper, the luminance component is separated from the resized YCbCr image and its edges are detected with the Canny edge detector. Then, we divide the binary edge image into 16 local regions and calculate the edge level percentage in each of them. Afterward, we use the edge level percentage to analyze the complexity of each local region included in the luminance component. Finally, according to the error function between the measured intensity and the calculated intensity, and the constraint function for an infinite light source model, we calculate the illuminant directions of the luminance component's three local regions, which meet the requirements of lower complexity and larger average gray value, and synthesize them as the final illuminant direction. Unlike previous works, the proposed method requires neither all of the information of the image nor the texture that is included in the training set. Experimental results show that the proposed method works better at the correct rate and execution time than the existing ones.

  4. A Fixed-Pattern Noise Correction Method Based on Gray Value Compensation for TDI CMOS Image Sensor.

    Science.gov (United States)

    Liu, Zhenwang; Xu, Jiangtao; Wang, Xinlei; Nie, Kaiming; Jin, Weimin

    2015-09-16

    In order to eliminate the fixed-pattern noise (FPN) in the output image of time-delay-integration CMOS image sensor (TDI-CIS), a FPN correction method based on gray value compensation is proposed. One hundred images are first captured under uniform illumination. Then, row FPN (RFPN) and column FPN (CFPN) are estimated based on the row-mean vector and column-mean vector of all collected images, respectively. Finally, RFPN are corrected by adding the estimated RFPN gray value to the original gray values of pixels in the corresponding row, and CFPN are corrected by subtracting the estimated CFPN gray value from the original gray values of pixels in the corresponding column. Experimental results based on a 128-stage TDI-CIS show that, after correcting the FPN in the image captured under uniform illumination with the proposed method, the standard-deviation of row-mean vector decreases from 5.6798 to 0.4214 LSB, and the standard-deviation of column-mean vector decreases from 15.2080 to 13.4623 LSB. Both kinds of FPN in the real images captured by TDI-CIS are eliminated effectively with the proposed method.

  5. Support Vector Machine Untuk Klasifikasi Citra Jenis Daging Berdasarkan Tekstur Menggunakan Ekstraksi Ciri Gray Level Co-Occurrence Matrices (GLCM

    Directory of Open Access Journals (Sweden)

    Neneng Neneng

    2016-11-01

    Full Text Available Texture is one of the most important features for image analysis, which provides informations such as the composition of texture on the surface structure, changes of the intensity, or brightness. Gray level co-occurence matrix (GLCM is a method that can be used for statistical texture analysis. GLCM has proven to be the most powerful texture descriptors used in image analysis. This study uses the four-way GLCM 0o, 45o, 90o, and 135o. Support vector machine (SVM is a machine learning that can be used for image classification. SVM has a high generalization capability without any requirement of additional knowledge, even with the high dimension of the input space. The data used in this study are the image of goat meat, buffalo meat, horse meat, and beef with shooting distance 20 cm, 30 cm and 40 cm. The result of this study shows that the best recognition rate of 87.5% was taken at a distance of 20 cm with neighboring pixels distance d = 2 in the direction GLCM 135o.

  6. Analysis on imaging features of mammography in computer radiography and investigation on gray scale transform and energy subtraction

    International Nuclear Information System (INIS)

    Feng Shuli

    2003-01-01

    In this dissertation, a novel transform method based on human visual response features for gray scale mammographic imaging in computer radiography (CR) is presented. The parameters for imaging quality on CR imaging for mammography were investigated experimentally. In addition, methods for image energy subtraction and a novel method of image registration for mammography of CR imaging are presented. Because the images are viewed and investigated by humans, the method of displaying differences in gray scale images is more convenient if the gray scale differences are displayed in a manner commensurate with human visual response principles. Through transformation of image gray scale with this method, the contrast of the image will be enhanced and the capability for humans to extract the useful information from the image will be increased. Tumors and microcalcifications are displayed in a form for humans to view more simply after transforming the image. The method is theoretically and experimentally investigated. Through measurement of the parameters of a geometrically blurred image, MTF, DQE, and ROC on CR imaging, and also comparison with the imaging quality of screen-film systems, the results indicate that CR imaging qualities in DQE and ROC are better than those of screen-film systems. In geometric blur of the image and MTF, the differences in image quality between CR and the screen-film system are very small. The results suggest that the CR system can replace the screen-film system for mammography imaging. In addition, the results show that the optimal imaging energy for CR mammography is about 24 kV. This condition indicates that the imaging energy of the CR system is lower than that of the screen-film system and, therefore, the x-ray dose to the patient for mammography with the CR system is lower than that with the screen-film system. Based on the difference of penetrability of x ray with different wavelength, and the fact that the part of the x-ray beam will pass

  7. Transition Temperatures of Thermotropic Liquid Crystals from the Local Binary Gray Level Cooccurrence Matrix

    Directory of Open Access Journals (Sweden)

    S. Sreehari Sastry

    2012-01-01

    Full Text Available This paper presents a method which combines the statistical analysis with texture structural analysis called Local Binary Gray Level Cooccurrence Matrix (LBGLCM to investigate the phase transition temperatures of thermotropic p,n-alkyloxy benzoic acid (nOBA, n=4,6,8,10 and 12 liquid crystals. Textures of the homeotropically aligned liquid crystal compounds are recorded as a function of temperature using polarizing optical microscope attached to the hot stage and high resolution camera. In this method, second-order statistical parameters (contrast, energy, homogeneity, and correlation are extracted from the LBGLCM of the textures. The changes associatedwiththe values of extracted parameters as a function of temperature are a helpful process to identify the phases and phase transition temperatures of the samples. Results obtained from this method have validity and are in good agreement with the literature.

  8. An efficient approach for differentiating Alzheimer's disease from normal elderly based on multicenter MRI using gray-level invariant features.

    Directory of Open Access Journals (Sweden)

    Muwei Li

    Full Text Available Machine learning techniques, along with imaging markers extracted from structural magnetic resonance images, have been shown to increase the accuracy to differentiate patients with Alzheimer's disease (AD from normal elderly controls. Several forms of anatomical features, such as cortical volume, shape, and thickness, have demonstrated discriminative capability. These approaches rely on accurate non-linear image transformation, which could invite several nuisance factors, such as dependency on transformation parameters and the degree of anatomical abnormality, and an unpredictable influence of residual registration errors. In this study, we tested a simple method to extract disease-related anatomical features, which is suitable for initial stratification of the heterogeneous patient populations often encountered in clinical data. The method employed gray-level invariant features, which were extracted from linearly transformed images, to characterize AD-specific anatomical features. The intensity information from a disease-specific spatial masking, which was linearly registered to each patient, was used to capture the anatomical features. We implemented a two-step feature selection for anatomic recognition. First, a statistic-based feature selection was implemented to extract AD-related anatomical features while excluding non-significant features. Then, seven knowledge-based ROIs were used to capture the local discriminative powers of selected voxels within areas that were sensitive to AD or mild cognitive impairment (MCI. The discriminative capability of the proposed feature was measured by its performance in differentiating AD or MCI from normal elderly controls (NC using a support vector machine. The statistic-based feature selection, together with the knowledge-based masks, provided a promising solution for capturing anatomical features of the brain efficiently. For the analysis of clinical populations, which are inherently heterogeneous

  9. Local Directional Probability Optimization for Quantification of Blurred Gray/White Matter Junction in Magnetic Resonance Image

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    Xiaoxia Qu

    2017-09-01

    Full Text Available The blurred gray/white matter junction is an important feature of focal cortical dysplasia (FCD lesions. FCD is the main cause of epilepsy and can be detected through magnetic resonance (MR imaging. Several earlier studies have focused on computing the gradient magnitude of the MR image and used the resulting map to model the blurred gray/white matter junction. However, gradient magnitude cannot quantify the blurred gray/white matter junction. Therefore, we proposed a novel algorithm called local directional probability optimization (LDPO for detecting and quantifying the width of the gray/white matter boundary (GWB within the lesional areas. The proposed LDPO method mainly consists of the following three stages: (1 introduction of a hidden Markov random field-expectation-maximization algorithm to compute the probability images of brain tissues in order to obtain the GWB region; (2 generation of local directions from gray matter (GM to white matter (WM passing through the GWB, considering the GWB to be an electric potential field; (3 determination of the optimal local directions for any given voxel of GWB, based on iterative searching of the neighborhood. This was then used to measure the width of the GWB. The proposed LDPO method was tested on real MR images of patients with FCD lesions. The results indicated that the LDPO method could quantify the GWB width. On the GWB width map, the width of the blurred GWB in the lesional region was observed to be greater than that in the non-lesional regions. The proposed GWB width map produced higher F-scores in terms of detecting the blurred GWB within the FCD lesional region as compared to that of FCD feature maps, indicating better trade-off between precision and recall.

  10. Recognition for old Arabic manuscripts using spatial gray level dependence (SGLD

    Directory of Open Access Journals (Sweden)

    Ahmad M. Abd Al-Aziz

    2011-03-01

    Full Text Available Texture analysis forms the basis of object recognition and classification in several domains, one of these domains is historical document manuscripts because the manuscripts hold our culture heritage and also large numbers of undated manuscripts exist. This paper presents results for historical document classification of old Arabic manuscripts using texture analysis and a segmentation free approach. The main objective is to discriminate between historical documents of different writing styles to three different ages: Contemporary (Modern Age, Ottoman Age and Mamluk Age. This classification depends on a Spatial Gray-level Dependence (SGLD technique which provides eight distinct texture features for each sample document. We applied Stepwise Discriminant Analysis and Multiple discriminant analysis methods to decrease the dimensionality of features and extract training vector features from samples. To classify historical documents into three main historical age classes the decision tree classification is applied. The system has been tested on 48 Arabic historical manuscripts documents from the Dar Al-Kotob Al-Masria Library. Our results so far yield 95.83% correct classification for the historical Arabic documents.

  11. MR imaging of heterotopic gray matter; Heterotopia istoty szarej mozgu w obrazie MR

    Energy Technology Data Exchange (ETDEWEB)

    Kryst-Widzgowska, T.; Kozlowski, P.; Poniatowska, R. [Instytut Psychiatrii i Neurologii, Warsaw (Poland)

    1994-12-31

    Six patients with heterotopic gray matter were evaluated with MR. 5 patients had history of seizures. 4 cases were suspected of the cerebral tumor. In the MR examination areas of heterotopic gray matter were found along the posterior horn of the lateral ventricle on the one side in 4 cases and bilateraly in 2 cases. In 3 cases another brain abnormalities were also detected including: hypoplasia of corpus callosum, hypoplasia of brain hemisphere, cavum septi pellucidi. MR is a modality of choice in the assessment of abnormal gray matter migration. (author). 6 refs, 4 figs.

  12. Cognitive Function and Serum Hormone Levels Are Associated with Gray Matter Volume Decline in Female Patients with Prolactinomas

    Directory of Open Access Journals (Sweden)

    Shun Yao

    2018-01-01

    Full Text Available Background and objectiveCognitive impairments have been reported in patients with hyperprolactinemia; however, there is a lack of knowledge of brain structure alterations relevant to hyperprolactinemia in prolactinomas. Thus, we aimed to identify changes in brain structure in prolactinomas and to determine whether these changes are related to cognitive performance and clinical characteristics.MethodsParticipants were 32 female patients with prolactinomas and 26 healthy controls (HC matched for age, sex, education, and handedness. All participants underwent magnetic resonance imaging brain scans, neuropsychological assessments, and clinical evaluations. Voxel-based morphometry analysis was used to identify changes in gray matter volume (GMV. Partial correlation analysis and multiple linear regression were performed to determine the relationship between GMV, cognition, and clinical characteristics.ResultsCompared to HC, patients with prolactinomas demonstrated a decrease in GMV in the left hippocampus, left orbitofrontal cortex, right middle frontal cortex (MFC, and right inferior frontal cortex (IFC. In addition, patients performed worse than controls on tests for verbal memory and executive function, and this was significantly related to the GMV of the left hippocampus and right MFC, respectively. Moreover, in the patients, we found a negative relationship between serum prolactin levels and the GMV of the left hippocampus and right IFC, whereas a positive relationship was found between the GMV of the left hippocampus and serum levels of estradiol and luteinizing hormone.ConclusionIn patients with prolactinomas, specific brain structure abnormalities have been identified and are associated with cognitive impairments and dysfunctional hormones. This study enhances our understanding of brain structure changes that may occur with prolactinomas and provides novel and fundamental evidence for previous behavioral findings relevant to hyperprolactinemia.

  13. Contrast Enhancement Method Based on Gray and Its Distance Double-Weighting Histogram Equalization for 3D CT Images of PCBs

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    Lei Zeng

    2016-01-01

    Full Text Available Cone beam computed tomography (CBCT is a new detection method for 3D nondestructive testing of printed circuit boards (PCBs. However, the obtained 3D image of PCBs exhibits low contrast because of several factors, such as the occurrence of metal artifacts and beam hardening, during the process of CBCT imaging. Histogram equalization (HE algorithms cannot effectively extend the gray difference between a substrate and a metal in 3D CT images of PCBs, and the reinforcing effects are insignificant. To address this shortcoming, this study proposes an image enhancement algorithm based on gray and its distance double-weighting HE. Considering the characteristics of 3D CT images of PCBs, the proposed algorithm uses gray and its distance double-weighting strategy to change the form of the original image histogram distribution, suppresses the grayscale of a nonmetallic substrate, and expands the grayscale of wires and other metals. The proposed algorithm also enhances the gray difference between a substrate and a metal and highlights metallic materials. The proposed algorithm can enhance the gray value of wires and other metals in 3D CT images of PCBs. It applies enhancement strategies of changing gray and its distance double-weighting mechanism to adapt to this particular purpose. The flexibility and advantages of the proposed algorithm are confirmed by analyses and experimental results.

  14. The role of gray and white matter segmentation in quantitative proton MR spectroscopic imaging.

    Science.gov (United States)

    Tal, Assaf; Kirov, Ivan I; Grossman, Robert I; Gonen, Oded

    2012-12-01

    Since the brain's gray matter (GM) and white matter (WM) metabolite concentrations differ, their partial volumes can vary the voxel's ¹H MR spectroscopy (¹H-MRS) signal, reducing sensitivity to changes. While single-voxel ¹H-MRS cannot differentiate between WM and GM signals, partial volume correction is feasible by MR spectroscopic imaging (MRSI) using segmentation of the MRI acquired for VOI placement. To determine the magnitude of this effect on metabolic quantification, we segmented a 1-mm³ resolution MRI into GM, WM and CSF masks that were co-registered with the MRSI grid to yield their partial volumes in approximately every 1 cm³ spectroscopic voxel. Each voxel then provided one equation with two unknowns: its i- metabolite's GM and WM concentrations C(i) (GM) , C(i) (WM) . With the voxels' GM and WM volumes as independent coefficients, the over-determined system of equations was solved for the global averaged C(i) (GM) and C(i) (WM) . Trading off local concentration differences offers three advantages: (i) higher sensitivity due to combined data from many voxels; (ii) improved specificity to WM versus GM changes; and (iii) reduced susceptibility to partial volume effects. These improvements made no additional demands on the protocol, measurement time or hardware. Applying this approach to 18 volunteered 3D MRSI sets of 480 voxels each yielded N-acetylaspartate, creatine, choline and myo-inositol C(i) (GM) concentrations of 8.5 ± 0.7, 6.9 ± 0.6, 1.2 ± 0.2, 5.3 ± 0.6 mM, respectively, and C(i) (WM) concentrations of 7.7 ± 0.6, 4.9 ± 0.5, 1.4 ± 0.1 and 4.4 ± 0.6mM, respectively. We showed that unaccounted voxel WM or GM partial volume can vary absolute quantification by 5-10% (more for ratios), which can often double the sample size required to establish statistical significance. Copyright © 2012 John Wiley & Sons, Ltd.

  15. Hot Spots Detection of Operating PV Arrays through IR Thermal Image Using Method Based on Curve Fitting of Gray Histogram

    Directory of Open Access Journals (Sweden)

    Jiang Lin

    2016-01-01

    Full Text Available The overall efficiency of PV arrays is affected by hot spots which should be detected and diagnosed by applying responsible monitoring techniques. The method using the IR thermal image to detect hot spots has been studied as a direct, noncontact, nondestructive technique. However, IR thermal images suffer from relatively high stochastic noise and non-uniformity clutter, so the conventional methods of image processing are not effective. The paper proposes a method to detect hotspots based on curve fitting of gray histogram. The result of MATLAB simulation proves the method proposed in the paper is effective to detect the hot spots suppressing the noise generated during the process of image acquisition.

  16. Evaluation of cost functions for gray value matching of two-dimensional images in radiotherapy

    NARCIS (Netherlands)

    Dekker, Niels; Ploeger, Lennert S.; van Herk, Marcel

    2003-01-01

    In external beam radiotherapy, portal imaging is applied for verification of the patient setup. Current automatic methods for portal image registration, which are often based on segmentation of anatomical structures, are especially successful for images of the pelvic region. For portal images of

  17. Influence of soft tissues on mandibular gray scale levels Influência dos tecidos moles sobre os níveis de cinza mandibulares

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Couto Souza

    2004-03-01

    Full Text Available The purpose of this study was to analyze the gray levels, expressed in pixels, of the mandibular retromolar region, with regard to the influence of muscular and fat soft tissues near this region. Fifteen dry mandibles were X-rayed with the presence of soft tissue simulators. The radiographs were digitized and evaluated by Digora® software. A one cm thick layer of wax was used as a simulator of the muscular soft tissue. Animal fat samples of different thicknesses - 0.5, 1.0, 1.5 and 2.0 cm - were used as a simulator of the fat soft tissue. Results showed that the fat soft tissue simulator influenced the gray level values in pixels of the mandibular retromolar region when analyzed in different thicknesses using the Digora® digitized image software.O presente trabalho foi desenvolvido com o objetivo de analisar os níveis de cinza, expressos em "pixels", da região retromolar mandibular, considerando a influência dos tecidos moles muscular e, principalmente, adiposo adjacentes a essa região. Para o estudo, 15 mandíbulas secas foram tecnicamente radiografadas, sendo que as radiografias obtidas foram escaneadas e avaliadas pelo programa de imagens digitalizadas Digora®. Como simuladores dos tecidos muscular e adiposo, foram utilizadas cera utilidade na espessura de 1,0 cm e amostras de gordura animal em espessuras diferentes de 0,5; 1,0; 1,5 e 2,0 cm. Os resultados mostraram que o tecido adiposo foi capaz de influenciar a análise dos valores de níveis de cinza em "pixels" da região retromolar mandibular quando estudado em espessuras diferentes pelo programa de imagens digitalizadas Digora®.

  18. [Research on K-means clustering segmentation method for MRI brain image based on selecting multi-peaks in gray histogram].

    Science.gov (United States)

    Chen, Zhaoxue; Yu, Haizhong; Chen, Hao

    2013-12-01

    To solve the problem of traditional K-means clustering in which initial clustering centers are selected randomly, we proposed a new K-means segmentation algorithm based on robustly selecting 'peaks' standing for White Matter, Gray Matter and Cerebrospinal Fluid in multi-peaks gray histogram of MRI brain image. The new algorithm takes gray value of selected histogram 'peaks' as the initial K-means clustering center and can segment the MRI brain image into three parts of tissue more effectively, accurately, steadily and successfully. Massive experiments have proved that the proposed algorithm can overcome many shortcomings caused by traditional K-means clustering method such as low efficiency, veracity, robustness and time consuming. The histogram 'peak' selecting idea of the proposed segmentootion method is of more universal availability.

  19. What happened to gray whales during the Pleistocene? The ecological impact of sea-level change on benthic feeding areas in the North Pacific Ocean.

    Directory of Open Access Journals (Sweden)

    Nicholas D Pyenson

    Full Text Available Gray whales (Eschrichtius robustus undertake long migrations, from Baja California to Alaska, to feed on seasonally productive benthos of the Bering and Chukchi seas. The invertebrates that form their primary prey are restricted to shallow water environments, but global sea-level changes during the Pleistocene eliminated or reduced this critical habitat multiple times. Because the fossil record of gray whales is coincident with the onset of Northern Hemisphere glaciation, gray whales survived these massive changes to their feeding habitat, but it is unclear how.We reconstructed gray whale carrying capacity fluctuations during the past 120,000 years by quantifying gray whale feeding habitat availability using bathymetric data for the North Pacific Ocean, constrained by their maximum diving depth. We calculated carrying capacity based on modern estimates of metabolic demand, prey availability, and feeding duration; we also constrained our estimates to reflect current population size and account for glaciated and non-glaciated areas in the North Pacific. Our results show that key feeding areas eliminated by sea-level lowstands were not replaced by commensurate areas. Our reconstructions show that such reductions affected carrying capacity, and harmonic means of these fluctuations do not differ dramatically from genetic estimates of carrying capacity.Assuming current carrying capacity estimates, Pleistocene glacial maxima may have created multiple, weak genetic bottlenecks, although the current temporal resolution of genetic datasets does not test for such signals. Our results do not, however, falsify molecular estimates of pre-whaling population size because those abundances would have been sufficient to survive the loss of major benthic feeding areas (i.e., the majority of the Bering Shelf during glacial maxima. We propose that gray whales survived the disappearance of their primary feeding ground by employing generalist filter-feeding modes

  20. H-1 chemical shift imaging of the brain in guanidino methyltransferase deficiency, a creatine deficiency syndrome; guanidinoacetate accumulation in the gray matter

    NARCIS (Netherlands)

    Sijens, PE; Verbruggen, KT; Meiners, LC; Soorani-Lunsing, RJ; Rake, JP; Oudkerk, M

    MR spectroscopy results in a mild case of guanidinoacetate methyltransferase (GAMT) deficiency are presented. The approach differs from previous MRS studies in the acquisition of a chemical shift imaging spectral map showing gray and white matter with the corresponding spectra in one overview. MR

  1. Late effects of high-dose adjuvant chemotherapy on white and gray matter in breast cancer survivors: Converging results from multimodal magnetic resonance imaging

    NARCIS (Netherlands)

    de Ruiter, Michiel B.; Reneman, Liesbeth; Boogerd, Willem; Veltman, Dick J.; Caan, Matthan; Douaud, Gwenaëlle; Lavini, Cristina; Linn, Sabine C.; Boven, Epie; van Dam, Frits S. A. M.; Schagen, Sanne B.

    2012-01-01

    The neural substrate underlying cognitive impairments after chemotherapy is largely unknown. Here, we investigated very late (>9 years) effects of adjuvant high-dose chemotherapy on brain white and gray matter in primary breast cancer survivors (n = 17) with multimodal magnetic resonance imaging

  2. Gray matter alterations and correlation of nutritional intake with the gray matter volume in prediabetes

    Science.gov (United States)

    Hou, Yi-Cheng; Lai, Chien-Han; Wu, Yu-Te; Yang, Shwu-Huey

    2016-01-01

    Abstract The neurophysiology of prediabetes plays an important role in preventive medicine. The dysregulation of glucose metabolism is likely linked to changes in neuron-related gray matter. Therefore, we designed this study to investigate gray matter alterations in medication-naive prediabetic patients. We expected to find alterations in the gray matter of prediabetic patients. A total of 64 prediabetic patients and 54 controls were enrolled. All subjects received T1 scans using a 3-T magnetic resonance imaging machine. Subjects also completed nutritional intake records at the 24-hour and 3-day time points to determine their carbohydrate, protein, fat, and total calorie intake. We utilized optimized voxel-based morphometry to estimate the gray matter differences between the patients and controls. In addition, the preprandial serum glucose level and the carbohydrate, protein, fat, and total calorie intake levels were tested to determine whether these parameters were correlated with the gray matter volume. Prediabetic patients had lower gray matter volumes than controls in the right anterior cingulate gyrus, right posterior cingulate gyrus, left insula, left super temporal gyrus, and left middle temporal gyrus (corrected P prediabetic patients. PMID:27336893

  3. Texture Feature Analysis for Different Resolution Level of Kidney Ultrasound Images

    Science.gov (United States)

    Kairuddin, Wan Nur Hafsha Wan; Mahmud, Wan Mahani Hafizah Wan

    2017-08-01

    Image feature extraction is a technique to identify the characteristic of the image. The objective of this work is to discover the texture features that best describe a tissue characteristic of a healthy kidney from ultrasound (US) image. Three ultrasound machines that have different specifications are used in order to get a different quality (different resolution) of the image. Initially, the acquired images are pre-processed to de-noise the speckle to ensure the image preserve the pixels in a region of interest (ROI) for further extraction. Gaussian Low- pass Filter is chosen as the filtering method in this work. 150 of enhanced images then are segmented by creating a foreground and background of image where the mask is created to eliminate some unwanted intensity values. Statistical based texture features method is used namely Intensity Histogram (IH), Gray-Level Co-Occurance Matrix (GLCM) and Gray-level run-length matrix (GLRLM).This method is depends on the spatial distribution of intensity values or gray levels in the kidney region. By using One-Way ANOVA in SPSS, the result indicated that three features (Contrast, Difference Variance and Inverse Difference Moment Normalized) from GLCM are not statistically significant; this concludes that these three features describe a healthy kidney characteristics regardless of the ultrasound image quality.

  4. Global gray matter changes in posterior cortical atrophy: A serial imaging study

    NARCIS (Netherlands)

    Lehmann, M.; Barnes, J.; Ridgway, G.R.; Ryan, N.S.; Warrington, E.K.; Crutch, S.J.; Fox, N.C.

    2012-01-01

    Background: Posterior cortical atrophy (PCA) is a neurodegenerative condition predominantly associated with Alzheimer's disease (AD) pathology. Cross-sectional imaging studies have shown different atrophy patterns in PCA patients compared with typical amnestic Alzheimer's disease (tAD) patients,

  5. The effects of gray scale image processing on digital mammography interpretation performance.

    Science.gov (United States)

    Cole, Elodia B; Pisano, Etta D; Zeng, Donglin; Muller, Keith; Aylward, Stephen R; Park, Sungwook; Kuzmiak, Cherie; Koomen, Marcia; Pavic, Dag; Walsh, Ruth; Baker, Jay; Gimenez, Edgardo I; Freimanis, Rita

    2005-05-01

    To determine the effects of three image-processing algorithms on diagnostic accuracy of digital mammography in comparison with conventional screen-film mammography. A total of 201 cases consisting of nonprocessed soft copy versions of the digital mammograms acquired from GE, Fischer, and Trex digital mammography systems (1997-1999) and conventional screen-film mammograms of the same patients were interpreted by nine radiologists. The raw digital data were processed with each of three different image-processing algorithms creating three presentations-manufacturer's default (applied and laser printed to film by each of the manufacturers), MUSICA, and PLAHE-were presented in soft copy display. There were three radiologists per presentation. Area under the receiver operating characteristic curve for GE digital mass cases was worse than screen-film for all digital presentations. The area under the receiver operating characteristic for Trex digital mass cases was better, but only with images processed with the manufacturer's default algorithm. Sensitivity for GE digital mass cases was worse than screen film for all digital presentations. Specificity for Fischer digital calcifications cases was worse than screen film for images processed in default and PLAHE algorithms. Specificity for Trex digital calcifications cases was worse than screen film for images processed with MUSICA. Specific image-processing algorithms may be necessary for optimal presentation for interpretation based on machine and lesion type.

  6. Generating high gray-level resolution monochrome displays with conventional computer graphics cards and color monitors.

    Science.gov (United States)

    Li, Xiangrui; Lu, Zhong-Lin; Xu, Pengjing; Jin, Jianzhong; Zhou, Yifeng

    2003-11-30

    Display systems based on conventional computer graphics cards are capable of generating images with about 8-bit luminance resolution. However, most vision experiments require more than 12 bits of luminance resolution. Pelli and Zhang [Spatial Vis. 10 (1997) 443] described a video attenuator for generating high luminance resolution displays on a monochrome monitor, or for driving just the green gun of a color monitor. Here we show how to achieve a white display by adding video amplifiers to duplicate the monochrome signal to drive all three guns of any color monitor. Because of the lack of the availability of high quality monochrome monitors, our method provides an inexpensive way to achieve high-resolution monochromatic displays using conventional, easy-to-get equipment. We describe the design principles, test results, and a few additional functionalities.

  7. Measures of Morphological Complexity of Gray Matter on Magnetic Resonance Imaging for Control Age Grouping

    OpenAIRE

    Pham, Tuan; Abe, Taishi; Oka, Ryuichi; Chen, Yung-Fu

    2015-01-01

    Current brain-age prediction methods using magnetic resonance imaging (MRI) attempt to estimate the physiological brain age via some kind of machine learning of chronological brain age data to perform the classification task. Such a predictive approach imposes greater risk of either over-estimate or under-estimate, mainly due to limited training data. A new conceptual framework for more reliable MRI-based brain-age prediction is by systematic brain-age grouping via the implementation of the p...

  8. Page segmentation and text extraction from gray-scale images in microfilm format

    Science.gov (United States)

    Yuan, Qing; Tan, Chew Lim

    2000-12-01

    The paper deals with a suitably designed system that is being used to separate textual regions from graphics regions and locate textual data from textured background. We presented a method based on edge detection to automatically locate text in some noise infected grayscale newspaper images with microfilm format. The algorithm first finds the appropriate edges of textual region using Canny edge detector, and then by edge merging it makes use of edge features to do block segmentation and classification, afterwards feature aided connected component analysis was used to group homogeneous textual regions together within the scope of its bounding box. We can obtain an efficient block segmentation with reduced memory size by introducing the TLC. The proposed method has been used to locate text in a group of newspaper images with multiple page layout. Initial results are encouraging, we would expand the experiment data to over 300 microfilm images with different layout structures, promising result is anticipated with corresponding modification on the prototype of former algorithm to make it more robust and suitable to different cases.

  9. Assessing water pollution level and gray water footprint of anthropogenic nitrogen in agricultural system

    Science.gov (United States)

    Huang, Guorui; Chen, Han; Yu, Chaoqing

    2017-04-01

    Water pollution has become a global problem which is one of the most critical issues of today's water treatment. At a spatial resolution of 10km, we use the DeNitrification-DeComposition (DNDC) model to simulate the biogeochemical processes for major cropping systems from 1955 to 2014, estimate the anthropogenic nitrogen loads to fresh, and calculate the resultant grey water footprints and N-related water pollution level in China. The accumulated annual Nitrogen loads to fresh from agricultural system is 0.38Tg in 1955 and 4.42Tg in 2014, while the grey water footprints vary from 1.53 billion m3 to 17.67 billion m3, respectively. N loads in north of China contributes much more on the N leaching because of the high fertilizer but in south of China, it is mainly focused on the N runoff because of the heavy rain. There are more than 25% of grids with WPL>1 (exceed the water capacity of assimilation), which is mainly located on the North China Plain.

  10. Measures of Morphological Complexity of Gray Matter on Magnetic Resonance Imaging for Control Age Grouping

    Directory of Open Access Journals (Sweden)

    Tuan D. Pham

    2015-12-01

    Full Text Available Current brain-age prediction methods using magnetic resonance imaging (MRI attempt to estimate the physiological brain age via some kind of machine learning of chronological brain age data to perform the classification task. Such a predictive approach imposes greater risk of either over-estimate or under-estimate, mainly due to limited training data. A new conceptual framework for more reliable MRI-based brain-age prediction is by systematic brain-age grouping via the implementation of the phylogenetic tree reconstruction and measures of information complexity. Experimental results carried out on a public MRI database suggest the feasibility of the proposed concept.

  11. Imaging of olfactory bulb and gray matter volumes in brain areas associated with olfactory function in patients with Parkinson's disease and multiple system atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Shun, E-mail: shchen_2013@163.com [Department of Neurology, The First Affiliated Hospital of Guangzhou Medical College (China); Tan, Hong-yu, E-mail: honhyutan@21cn.com [Department of Neurology, The First Affiliated Hospital of Guangzhou Medical College (China); Wu, Zhuo-hua, E-mail: zhh88@126.com [Department of Neurology, The First Affiliated Hospital of Guangzhou Medical College (China); Sun, Chong-peng, E-mail: Suncp2002@gmail.com [Imaging Center, The First Affiliated Hospital of Guangzhou Medical College (China); He, Jian-xun, E-mail: xundog@163.com [Imaging Center, The First Affiliated Hospital of Guangzhou Medical College (China); Li, Xin-chun, E-mail: xinchunli@163.com [Imaging Center, The First Affiliated Hospital of Guangzhou Medical College (China); Shao, Ming, E-mail: yimshao@126.com [Department of Neurology, The First Affiliated Hospital of Guangzhou Medical College (China)

    2014-03-15

    We explored if magnetic resonance imaging sequences might aid in the clinical differential diagnosis of idiopathic Parkinson's disease (IPD) and multiple system atrophy (MSA). We measured the volumes of the olfactory bulb, the olfactory tract, and olfaction-associated cortical gray matter in 20 IPD patients, 14 MSA patients, and 12 normal subjects, using high-resolution magnetic resonance imaging sequences in combination with voxel-based statistical analysis. We found that, compared to normal subjects and MSA patients, the volumes of the olfactory bulb and tract were significantly reduced in IPD patients. The gray matter volume of IPD patients decreased in the following order: the olfactory area to the right of the piriform cortex, the right amygdala, the left entorhinal cortex, and the left occipital lobe. Further, the total olfactory bulb volume of IPD patients was associated with the duration of disease. The entorhinal cortical gray matter volume was negatively associated with the UPDRS III score. Conclusion: Structural volumes measured by high-resolution magnetic resonance imaging may potentially be used for differential diagnosis of IPD from MSA.

  12. Imaging of olfactory bulb and gray matter volumes in brain areas associated with olfactory function in patients with Parkinson's disease and multiple system atrophy

    International Nuclear Information System (INIS)

    Chen, Shun; Tan, Hong-yu; Wu, Zhuo-hua; Sun, Chong-peng; He, Jian-xun; Li, Xin-chun; Shao, Ming

    2014-01-01

    We explored if magnetic resonance imaging sequences might aid in the clinical differential diagnosis of idiopathic Parkinson's disease (IPD) and multiple system atrophy (MSA). We measured the volumes of the olfactory bulb, the olfactory tract, and olfaction-associated cortical gray matter in 20 IPD patients, 14 MSA patients, and 12 normal subjects, using high-resolution magnetic resonance imaging sequences in combination with voxel-based statistical analysis. We found that, compared to normal subjects and MSA patients, the volumes of the olfactory bulb and tract were significantly reduced in IPD patients. The gray matter volume of IPD patients decreased in the following order: the olfactory area to the right of the piriform cortex, the right amygdala, the left entorhinal cortex, and the left occipital lobe. Further, the total olfactory bulb volume of IPD patients was associated with the duration of disease. The entorhinal cortical gray matter volume was negatively associated with the UPDRS III score. Conclusion: Structural volumes measured by high-resolution magnetic resonance imaging may potentially be used for differential diagnosis of IPD from MSA

  13. Gray and white matter asymmetries in healthy individuals aged 21-29 years: a voxel-based morphometry and diffusion tensor imaging study.

    Science.gov (United States)

    Takao, Hidemasa; Abe, Osamu; Yamasue, Hidenori; Aoki, Shigeki; Sasaki, Hiroki; Kasai, Kiyoto; Yoshioka, Naoki; Ohtomo, Kuni

    2011-10-01

    The hemispheres of the human brain are functionally and structurally asymmetric. The study of structural asymmetries provides important clues to the neuroanatomical basis of lateralized brain functions. Previous studies have demonstrated age-related changes in morphology and diffusion properties of brain tissue. In this study, we simultaneously explored gray and white matter asymmetry using voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) in 109 young healthy individuals (58 females and 51 males). To eliminate the potential confounding effects of aging and handedness, we restricted the study to right-handed subjects aged 21-29 years. VBM and voxel-based analysis of fractional anisotropy (FA) maps derived from DTI revealed a number of gray matter volume asymmetries (including the right frontal and left occipital petalias and leftward asymmetry of the planum temporale) and white matter FA asymmetries (including leftward asymmetry of the arcuate fasciculus, cingulum, and corticospinal tract). There was no significant effect of sex on gray and white matter asymmetry. Leftward volume asymmetry of the planum temporale and leftward FA asymmetry of the arcuate fasciculus were simultaneously demonstrated. Post hoc analysis showed that the gray matter volume of the planum temporale and FA of the arcuate fasciculus were positively related (Pearson correlation coefficient, 0.43; P < 0.0001). The results of our study demonstrate gray and white matter asymmetry in right-handed healthy young adults and suggest that leftward volume asymmetry of the planum temporale and leftward FA asymmetry of the arcuate fasciculus may be related. Copyright © 2010 Wiley-Liss, Inc.

  14. Higher Adolescent Body Mass Index is Associated with Lower Regional Gray and White Matter Volumes and Lower Levels of Positive Emotionality

    Directory of Open Access Journals (Sweden)

    James T Kennedy

    2016-09-01

    Full Text Available Adolescent obesity is associated with an increased chance of developing serious health risks later in life. Identifying the neurobiological and personality factors related to increases in adiposity is important to understanding what drives maladaptive consummatory and exercise behaviors that result in obesity. Previous research has largely focused on adults with few findings published on interactions among adiposity, brain structure, and personality. In this study, Voxel Based Morphometry (VBM was used to identify associations between gray and white matter volumes and increasing adiposity, as measured by Body Mass Index percentile (BMI%, in 137 adolescents (age range: 9-20 years, Body Mass Index percentile range: 5.16-99.56. Variations in gray and white matter volume and BMI% were then linked to individual differences in personality measures from the Multidimensional Personality Questionnaire (MPQ. After controlling for age and other covariates, BMI% correlated negatively with gray matter volume in the bilateral caudate (right: partial r = -0.338, left: r -0.404, medial prefrontal cortex (partial r = -0.339, anterior cingulate (partial r = -0.312, bilateral frontal pole (right: partial r = -0.368, left: r= -0.316, and uncus (partial r = -0.475 as well as white matter volume bilaterally in the anterior limb of the internal capsule (right: partial r = -0.34, left: r = -0.386, extending to the left middle frontal subgyral white matter. Agentic Positive Emotionality (PEM-AG was correlated negatively with BMI% (partial r = -0.384. PEM-AG was correlated positively with gray matter volume in the right uncus (partial r = 0.329. These results suggest that higher levels of adiposity in adolescents are associated with lower trait levels in reward-related personality domains, as well as structural variations in brain regions associated with reward processing, control, and sensory integration.

  15. GPU accelerated edge-region based level set evolution constrained by 2D gray-scale histogram.

    Science.gov (United States)

    Balla-Arabé, Souleymane; Gao, Xinbo; Wang, Bin

    2013-07-01

    Due to its intrinsic nature which allows to easily handle complex shapes and topological changes, the level set method (LSM) has been widely used in image segmentation. Nevertheless, LSM is computationally expensive, which limits its applications in real-time systems. For this purpose, we propose a new level set algorithm, which uses simultaneously edge, region, and 2D histogram information in order to efficiently segment objects of interest in a given scene. The computational complexity of the proposed LSM is greatly reduced by using the highly parallelizable lattice Boltzmann method (LBM) with a body force to solve the level set equation (LSE). The body force is the link with image data and is defined from the proposed LSE. The proposed LSM is then implemented using an NVIDIA graphics processing units to fully take advantage of the LBM local nature. The new algorithm is effective, robust against noise, independent to the initial contour, fast, and highly parallelizable. The edge and region information enable to detect objects with and without edges, and the 2D histogram information enable the effectiveness of the method in a noisy environment. Experimental results on synthetic and real images demonstrate subjectively and objectively the performance of the proposed method.

  16. Detection of sub micro Gray dose levels using OSL phosphor LiMgPO_4:Tb,B

    International Nuclear Information System (INIS)

    Rawat, N.S.; Dhabekar, Bhushan; Muthe, K.P.; Koul, D.K.; Datta, D.

    2017-01-01

    Highlights: • LiMgPO4:Tb,B has been studied and shown to possesses minimum measurable dose (MMD) in sub micro Gray region. • MMD as low as 0.49 µGy in readout time of less than 1 s at stimulation intensity of 32 mW/cm"2 has been achieved. • The OSL measurements for low doses has strengthened and validated this claim. • OSL spectrum shows several emission peaks and the prominent peak around 380 nm. - Abstract: Detection of sub micro Gray doses finds application in personnel and environmental monitoring, and nuclear forensics. Recently developed LiMgPO_4:Tb,B (LMP) is highly sensitive Optically Stimulated Luminescence (OSL) phosphor with excellent dosimetric properties. The OSL emission spectrum of LMP consists of several peaks attributed to characteristic Tb"3"+ emission. The OSL emission peak at 380 nm is favorable for bi-alkali PMT used in RISO reader system. It is demonstrated that significant improvement in dose detection threshold can be realized for LMP by optimization of continuous wave (CW–) OSL parameters like stimulation intensity and readout time. The minimum measurable dose (MMD) as low as 0.49 µGy in readout time of less than 1 s at stimulation intensity of 32 mW/cm"2 has been achieved using this phosphor. The recommendations for choice of parameters for personnel and environmental monitoring are also discussed.

  17. Detection of sub micro Gray dose levels using OSL phosphor LiMgPO{sub 4}:Tb,B

    Energy Technology Data Exchange (ETDEWEB)

    Rawat, N.S., E-mail: naru@barc.gov.in [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Dhabekar, Bhushan [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Muthe, K.P. [Technical Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Koul, D.K.; Datta, D. [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India)

    2017-04-15

    Highlights: • LiMgPO4:Tb,B has been studied and shown to possesses minimum measurable dose (MMD) in sub micro Gray region. • MMD as low as 0.49 µGy in readout time of less than 1 s at stimulation intensity of 32 mW/cm{sup 2} has been achieved. • The OSL measurements for low doses has strengthened and validated this claim. • OSL spectrum shows several emission peaks and the prominent peak around 380 nm. - Abstract: Detection of sub micro Gray doses finds application in personnel and environmental monitoring, and nuclear forensics. Recently developed LiMgPO{sub 4}:Tb,B (LMP) is highly sensitive Optically Stimulated Luminescence (OSL) phosphor with excellent dosimetric properties. The OSL emission spectrum of LMP consists of several peaks attributed to characteristic Tb{sup 3+} emission. The OSL emission peak at 380 nm is favorable for bi-alkali PMT used in RISO reader system. It is demonstrated that significant improvement in dose detection threshold can be realized for LMP by optimization of continuous wave (CW–) OSL parameters like stimulation intensity and readout time. The minimum measurable dose (MMD) as low as 0.49 µGy in readout time of less than 1 s at stimulation intensity of 32 mW/cm{sup 2} has been achieved using this phosphor. The recommendations for choice of parameters for personnel and environmental monitoring are also discussed.

  18. White and gray matter abnormalities in idiopathic rapid eye movement sleep behavior disorder: a diffusion-tensor imaging and voxel-based morphometry study.

    Science.gov (United States)

    Scherfler, Christoph; Frauscher, Birgit; Schocke, Michael; Iranzo, Alex; Gschliesser, Viola; Seppi, Klaus; Santamaria, Joan; Tolosa, Eduardo; Högl, Birgit; Poewe, Werner

    2011-02-01

    We applied diffusion-tensor imaging (DTI) including measurements of mean diffusivity (MD), a parameter of brain tissue integrity, fractional anisotropy (FA), a parameter of neuronal fiber integrity, as well as voxel-based morphometry (VBM), a measure of gray and white matter volume, to detect brain tissue changes in patients with idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD). Magnetic resonance imaging (MRI) was performed in 26 patients with iRBD (mean disease duration, 9.2 ± 6.4 years) and 14 age-matched healthy control subjects. Statistical parametric mapping (SPM) was applied to objectively identify focal changes of MRI parameters throughout the entire brain volume. SPM localized significant decreases of FA in the tegmentum of the midbrain and rostral pons and increases of MD within the pontine reticular formation overlapping with a cluster of decreased FA in the midbrain (p < 0.001). VBM revealed increases of gray matter densities in both hippocampi of iRBD patients (p < 0.001). The observed changes in the pontomesencephalic brainstem localized 2 areas harboring key neuronal circuits believed to be involved in the regulation of REM sleep and overlap with areas of structural brainstem damage causing symptomatic RBD in humans. Bilateral increases in gray matter density of the hippocampus suggest functional neuronal reorganization in this brain area in iRBD. This study indicates that DTI detects distinct structural brainstem tissue abnormalities in iRBD in the regions where REM is modulated. Further studies should explore the relationship between MRI pathology and the risk of patients with iRBD of developing alpha-synuclein-related neurodegenerative diseases like Parkinson disease. Copyright © 2010 American Neurological Association.

  19. A Gray-code-based color image representation method using TSNAM%TSNAM彩色图像的格雷码表示

    Institute of Scientific and Technical Information of China (English)

    郑运平; 张佳婧

    2012-01-01

    为了提高彩色图像模式的表示效率,借助于三角形和正方形布局问题的思想,将格雷码和位平面分解方法应用到彩色图像的三角形和正方形NAM表示方法(TSNAM)中,提出了一种基于格雷码的TSNAM彩色图像表示方法(GTSNAM).给出了GTSNAM表示算法的形式化描述,并对其存储结构、总数据量和时空复杂性进行了分析.理论分析和实验结果表明,与最新提出的TSNAM表示方法和经典的线性四元树(LQT)表示方法相比,GTSNAM表示方法具有更少的子模式数(或节点数),能够更有效地减少数据存储空间,因而是一种有效的彩色图像表示方法.%Inspired by an idea obtained from the triangle and the square packing problems, a new Gray-code-based color image representation method using a non-symmetry and anti-packing pattern representation model with the triangle and the square subpatterns (TSNAM) , also called the GTSNAM representation method, was proposed to improve the representation efficiency of color images by applying the Gray code and the bit-plane decomposition method. Also, a concrete algorithm of GTSNAM for color images was presented, and the storage structure, the total data amount, and the time and space complexities of the proposed algorithm were analyzed. By comparing the GTSNAM algorithm with those of the classic linear quadtree (LQT) and the latest TSNAM, which is not based on the Gray code, the theoretical and experimental results show that the former can greatly reduce the number of subpatterns or nodes and simultaneously save the storage space much more effectively than the latter ones. The GTSNAM algorithm is therefore shown to be a better method to represent color images.

  20. Multivariate imaging-genetics study of MRI gray matter volume and SNPs reveals biological pathways correlated with brain structural differences in Attention Deficit Hyperactivity Disorder

    Directory of Open Access Journals (Sweden)

    Sabin Khadka

    2016-07-01

    Full Text Available Background: Attention Deficit Hyperactivity Disorder (ADHD is a prevalent neurodevelopmental disorder affecting children, adolescents, and adults. Its etiology is not well-understood, but it is increasingly believed to result from diverse pathophysiologies that affect the structure and function of specific brain circuits. Although one of the best-studied neurobiological abnormalities in ADHD is reduced fronto-striatal-cerebellar gray matter volume, its specific genetic correlates are largely unknown. Methods: In this study, T1-weighted MR images of brain structure were collected from 198 adolescents (63 ADHD-diagnosed. A multivariate parallel independent component analysis technique (Para-ICA identified imaging-genetic relationships between regional gray matter volume and single nucleotide polymorphism data. Results: Para-ICA analyses extracted 14 components from genetic data and 9 from MR data. An iterative cross-validation using randomly-chosen sub-samples indicated acceptable stability of these ICA solutions. A series of partial correlation analyses controlling for age, sex, and ethnicity revealed two genotype-phenotype component pairs significantly differed between ADHD and non-ADHD groups, after a Bonferroni correction for multiple comparisons. The brain phenotype component not only included structures frequently found to have abnormally low volume in previous ADHD studies, but was also significantly associated with ADHD differences in symptom severity and performance on cognitive tests frequently found to be impaired in patients diagnosed with the disorder. Pathway analysis of the genotype component identified several different biological pathways linked to these structural abnormalities in ADHD. Conclusions: Some of these pathways implicate well-known dopaminergic neurotransmission and neurodevelopment hypothesized to be abnormal in ADHD. Other more recently implicated pathways included glutamatergic and GABA-eric physiological systems

  1. Developing a nomogram based on multiparametric magnetic resonance imaging for forecasting high-grade prostate cancer to reduce unnecessary biopsies within the prostate-specific antigen gray zone.

    Science.gov (United States)

    Niu, Xiang-Ke; Li, Jun; Das, Susant Kumar; Xiong, Yan; Yang, Chao-Bing; Peng, Tao

    2017-02-01

    Since 1980s the application of Prostate specific antigen (PSA) brought the revolution in prostate cancer diagnosis. However, it is important to underline that PSA is not the ideal screening tool due to its low specificity, which leads to the possible biopsy for the patient without High-grade prostate cancer (HGPCa). Therefore, the aim of this study was to establish a predictive nomogram for HGPCa in patients with PSA 4-10 ng/ml based on Prostate Imaging Reporting and Data System version 2 (PI-RADS v2), MRI-based prostate volume (PV), MRI-based PV-adjusted Prostate Specific Antigen Density (adjusted-PSAD) and other traditional classical parameters. Between January 2014 and September 2015, Of 151 men who were eligible for analysis were formed the training cohort. A prediction model for HGPCa was built by using backward logistic regression and was presented on a nomogram. The prediction model was evaluated by a validation cohort between October 2015 and October 2016 (n = 74). The relationship between the nomogram-based risk-score as well as other parameters with Gleason score (GS) was evaluated. All patients underwent 12-core systematic biopsy and at least one core targeted biopsy with transrectal ultrasonographic guidance. The multivariate analysis revealed that patient age, PI-RADS v2 score and adjusted-PSAD were independent predictors for HGPCa. Logistic regression (LR) model had a larger AUC as compared with other parameters alone. The most discriminative cutoff value for LR model was 0.36, the sensitivity, specificity, positive predictive value and negative predictive value were 87.3, 78.4, 76.3, and 90.4%, respectively and the diagnostic performance measures retained similar values in the validation cohort (AUC 0.82 [95% CI, 0.76-0.89]). For all patients with HGPCa (n = 50), adjusted-PSAD and nomogram-based risk-score were positively correlated with the GS of HGPCa in PSA gray zone (r = 0.455, P = 0.002 and r = 0.509, P = 0

  2. Identifikasi Tumbuhan Obat Herbal Berdasarkan Citra Daun Menggunakan Algoritma Gray Level Co-occurence Matrix dan K-Nearest Neighbor

    Directory of Open Access Journals (Sweden)

    Fittria Shofrotun Ni'mah

    2018-03-01

    Full Text Available Medicinal plants can be used as an alternative natural treatment, instead of chemical drugs. But because of too many types of plants and lack of knowledge, it will be difficult to identify these herbs. Computer assistance can be used to facilitate the identification of these herbs. This research proposes the identification of herbal plants based on leaf image using texture analysis. There are 10 types of herbal medicinal plants used in this study. The texture analysis used was GLCM by extracting contrast, correlation, energy, and homogeneity. Classification is done by KNN. The result of the experiment showed that the accuracy of identification using 9-fold cross-cross validation method was 83.33% using 9 subsets. Tumbuhan obat herbal bisa dijadikan sebagai alternatif pengobatan yang alami, selain obat-obatan kimia. Namun karena terlalu banyak jenis tumbuhan dan kurangnya pengetahuan, identifikasi tumbuhan berkhasiat akan sulit. Bantuan komputer dapat digunakan untuk memudahkan mengidentifikasi tumbuhan herbal tersebut. Penelitian ini mengusulkan identifikasi tumbuhan herbal berdasarkan citra daun menggunakan analisis tekstur. Ada 10 spesies tumbuhan obat herbal yang digunakan dalam penelitian ini. Analisis tekstur yang digunakan adalah GLCM dengan mengekstrak nilai kontras, korelasi, energi dan homogenitas. Klasifikasi dilakukan dengan KNN. Hasil percobaan menunjukkan akurasi identifikasi menggunakan metode 9-fold cross validation mencapai 83.33% dengan menggunakan 9 subset.

  3. 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)

    Lv, Xiao-Fei; Zheng, Xiao-Li; Zhang, Wei-Dong; Liu, Li-Zhi; Zhang, You-Ming; Chen, Ming-Yuan; Li, Li

    2014-01-01

    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.)

  4. Combination of radiological and gray level co-occurrence matrix textural features used to distinguish solitary pulmonary nodules by computed tomography.

    Science.gov (United States)

    Wu, Haifeng; Sun, Tao; Wang, Jingjing; Li, Xia; Wang, Wei; Huo, Da; Lv, Pingxin; He, Wen; Wang, Keyang; Guo, Xiuhua

    2013-08-01

    The objective of this study was to investigate the method of the combination of radiological and textural features for the differentiation of malignant from benign solitary pulmonary nodules by computed tomography. Features including 13 gray level co-occurrence matrix textural features and 12 radiological features were extracted from 2,117 CT slices, which came from 202 (116 malignant and 86 benign) patients. Lasso-type regularization to a nonlinear regression model was applied to select predictive features and a BP artificial neural network was used to build the diagnostic model. Eight radiological and two textural features were obtained after the Lasso-type regularization procedure. Twelve radiological features alone could reach an area under the ROC curve (AUC) of 0.84 in differentiating between malignant and benign lesions. The 10 selected characters improved the AUC to 0.91. The evaluation results showed that the method of selecting radiological and textural features appears to yield more effective in the distinction of malignant from benign solitary pulmonary nodules by computed tomography.

  5. Henry Gray, plagiarist.

    Science.gov (United States)

    Richardson, Ruth

    2016-03-01

    The first edition of Anatomy Descriptive and Surgical (1858) was greeted with accolades, but also provoked serious controversy concerning Henry Gray's failure to acknowledge the work of earlier anatomists. A review in the Medical Times (1859) accused Gray of intellectual theft. The journal took the unusual step of substantiating its indictment by publishing twenty parallel texts from Gray and from a pre-existing textbook, Quain's Anatomy. At the recent "Vesalius Continuum" conference in Zakynthos, Greece (2014) Professor Brion Benninger disputed the theft by announcing from the floor the results of a computer analysis of both texts, which he reported exonerated Gray by revealing no evidence of plagiarism. The analysis has not been forthcoming, however, despite requests. Here the historian of Gray's Anatomy supplements the argument set out in the Medical Times 150 years ago with data suggesting unwelcome personality traits in Henry Gray, and demonstrating the utility of others' work to his professional advancement. Fair dealing in the world of anatomy and indeed the genuineness of the lustre of medical fame are important matters, but whether quantitative evidence has anything to add to the discussion concerning Gray's probity can be assessed only if Benninger makes public his computer analysis. © 2015 Wiley Periodicals, Inc.

  6. Linked alterations in gray and white matter morphology in adults with high-functioning autism spectrum disorder: A multimodal brain imaging study

    Directory of Open Access Journals (Sweden)

    Takashi Itahashi

    2015-01-01

    Full Text Available Growing evidence suggests that a broad range of behavioral anomalies in people with autism spectrum disorder (ASD can be linked with morphological and functional alterations in the brain. However, the neuroanatomical underpinnings of ASD have been investigated using either structural magnetic resonance imaging (MRI or diffusion tensor imaging (DTI, and the relationships between abnormalities revealed by these two modalities remain unclear. This study applied a multimodal data-fusion method, known as linked independent component analysis (ICA, to a set of structural MRI and DTI data acquired from 46 adult males with ASD and 46 matched controls in order to elucidate associations between different aspects of atypical neuroanatomy of ASD. Linked ICA identified two composite components that showed significant between-group differences, one of which was significantly correlated with age. In the other component, participants with ASD showed decreased gray matter (GM volumes in multiple regions, including the bilateral fusiform gyri, bilateral orbitofrontal cortices, and bilateral pre- and post-central gyri. These GM changes were linked with a pattern of decreased fractional anisotropy (FA in several white matter tracts, such as the bilateral inferior longitudinal fasciculi, bilateral inferior fronto-occipital fasciculi, and bilateral corticospinal tracts. Furthermore, unimodal analysis for DTI data revealed significant reductions of FA along with increased mean diffusivity in those tracts for ASD, providing further evidence of disrupted anatomical connectivity. Taken together, our findings suggest that, in ASD, alterations in different aspects of brain morphology may co-occur in specific brain networks, providing a comprehensive view for understanding the neuroanatomy of this disorder.

  7. Gray matter network disruptions and amyloid beta in cognitively normal adults.

    Science.gov (United States)

    Tijms, Betty M; Kate, Mara Ten; Wink, Alle Meije; Visser, Pieter Jelle; Ecay, Mirian; Clerigue, Montserrat; Estanga, Ainara; Garcia Sebastian, Maite; Izagirre, Andrea; Villanua, Jorge; Martinez Lage, Pablo; van der Flier, Wiesje M; Scheltens, Philip; Sanz Arigita, Ernesto; Barkhof, Frederik

    2016-01-01

    Gray matter networks are disrupted in Alzheimer's disease (AD). It is unclear when these disruptions start during the development of AD. Amyloid beta 1-42 (Aβ42) is among the earliest changes in AD. We studied, in cognitively healthy adults, the relationship between Aβ42 levels in cerebrospinal fluid (CSF) and single-subject cortical gray matter network measures. Single-subject gray matter networks were extracted from structural magnetic resonance imaging scans in a sample of cognitively healthy adults (N = 185; age range 39-79, mini-mental state examination >25, N = 12 showed abnormal Aβ42 level and for 90 anatomical areas. Associations between continuous Aβ42 CSF levels and single-subject cortical gray matter network measures were tested. Smoothing splines were used to determine whether a linear or nonlinear relationship gave a better fit to the data. Lower Aβ42 CSF levels were linearly associated at whole brain level with lower connectivity density, and nonlinearly with lower clustering values and higher path length values, which is indicative of a less-efficient network organization. These relationships were specific to medial temporal areas, precuneus, and the middle frontal gyrus (all p levels can be related to gray matter networks disruptions. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Diagnostic reference levels in medical imaging

    International Nuclear Information System (INIS)

    Rosenstein, M.

    2001-01-01

    The paper proposes additional advice to national or local authorities and the clinical community on the application of diagnostic reference levels as a practical tool to manage radiation doses to patients in diagnostic radiology and nuclear medicine. A survey was made of the various approaches that have been taken by authoritative bodies to establish diagnostic reference levels for medical imaging tasks. There are a variety of ways to implement the idea of diagnostic reference levels, depending on the medical imaging task of interest, the national or local state of practice and the national or local preferences for technical implementation. The existing International Commission on Radiological Protection (ICRP) guidance is reviewed, the survey information is summarized, a set of unifying principles is espoused and a statement of additional advice that has been proposed to ICRP Committee 3 is presented. The proposed advice would meet a need for a unifying set of principles to provide a framework for diagnostic reference levels but would allow flexibility in their selection and use. While some illustrative examples are given, the proposed advice does not specify the specific quantities to be used, the numerical values to be set for the quantities or the technical details of how national or local authorities should implement diagnostic reference levels. (author)

  9. Images crossing borders: image and workflow sharing on multiple levels.

    Science.gov (United States)

    Ross, Peeter; Pohjonen, Hanna

    2011-04-01

    Digitalisation of medical data makes it possible to share images and workflows between related parties. In addition to linear data flow where healthcare professionals or patients are the information carriers, a new type of matrix of many-to-many connections is emerging. Implementation of shared workflow brings challenges of interoperability and legal clarity. Sharing images or workflows can be implemented on different levels with different challenges: inside the organisation, between organisations, across country borders, or between healthcare institutions and citizens. Interoperability issues vary according to the level of sharing and are either technical or semantic, including language. Legal uncertainty increases when crossing national borders. Teleradiology is regulated by multiple European Union (EU) directives and legal documents, which makes interpretation of the legal system complex. To achieve wider use of eHealth and teleradiology several strategic documents were published recently by the EU. Despite EU activities, responsibility for organising, providing and funding healthcare systems remains with the Member States. Therefore, the implementation of new solutions requires strong co-operation between radiologists, societies of radiology, healthcare administrators, politicians and relevant EU authorities. The aim of this article is to describe different dimensions of image and workflow sharing and to analyse legal acts concerning teleradiology in the EU.

  10. Structural imaging of the brain reveals decreased total brain and total gray matter volumes in obese but not in lean women with polycystic ovary syndrome compared to body mass index-matched counterparts.

    Science.gov (United States)

    Ozgen Saydam, Basak; Has, Arzu Ceylan; Bozdag, Gurkan; Oguz, Kader Karli; Yildiz, Bulent Okan

    2017-07-01

    To detect differences in global brain volumes and identify relations between brain volume and appetite-related hormones in women with polycystic ovary syndrome (PCOS) compared to body mass index-matched controls. Forty subjects participated in this study. Cranial magnetic resonance imaging and measurements of fasting ghrelin, leptin and glucagon-like peptide 1 (GLP-1), as well as GLP-1 levels during mixed-meal tolerance test (MTT), were performed. Total brain volume and total gray matter volume (GMV) were decreased in obese PCOS compared to obese controls (p lean PCOS and controls did not show a significant difference. Secondary analyses of regional brain volumes showed decreases in GMV of the caudate nucleus, ventral diencephalon and hippocampus in obese PCOS compared to obese controls (p lean patients with PCOS had lower GMV in the amygdala than lean controls (p PCOS, suggests volumetric reductions in global brain areas in obese women with PCOS. Functional studies with larger sample size are needed to determine physiopathological roles of these changes and potential effects of long-term medical management on brain structure of PCOS.

  11. 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.)

  12. Substance use and regional gray matter volume in individuals at high risk of psychosis.

    Science.gov (United States)

    Stone, James M; Bhattacharyya, Sagnik; Barker, Gareth J; McGuire, Philip K

    2012-02-01

    Individuals with an at risk mental state (ARMS) are at greatly increased risk of developing a psychotic illness. Risk of transition to psychosis is associated with regionally reduced cortical gray matter volume. There has been considerable interest in the interaction between psychosis risk and substance use. In this study we investigate the relationship between alcohol, cannabis and nicotine use with gray matter volume in ARMS subjects and healthy volunteers. Twenty seven ARMS subjects and 27 healthy volunteers took part in the study. All subjects underwent volumetric MRI imaging. The relationship between regional gray matter volume and cannabis use, smoking, and alcohol use in controls and ARMS subjects was analysed using voxel-based morphometry. In any region where a significant relationship with drug was present, data were analysed to determine if there was any group difference in this relationship. Alcohol intake was inversely correlated with gray matter volume in cerebellum, cannabis intake was use was inversely correlated with gray matter volume in prefrontal cortex and tobacco intake was inversely correlated with gray matter volume in left temporal cortex. There were no significant interactions by group in any region. There is no evidence to support the hypothesis of increased susceptibility to harmful effects of drugs and alcohol on regional gray matter in ARMS subjects. However, alcohol, tobacco and cannabis at low to moderate intake may be associated with lower gray matter in both ARMS subjects and healthy volunteers-possibly representing low-level cortical damage or change in neural plasticity. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Henry Gray's Anatomy.

    Science.gov (United States)

    Pearce, J M S

    2009-04-01

    Little is generally known of Henry Gray, the author of Gray's Anatomy, and even less of his colleague Henry Vandyke Carter, who played a vital role in the dissections and illustrations leading to the production of the first volume in 1859. This essay attempts to sketch briefly the salient, know aspects of these two men and their divergent careers. It traces succinctly the subsequent fate of the unique anatomy book that has influenced and instructed almost every student of medicine. (c) 2009 Wiley-Liss, Inc.

  14. Implementation of the Midway Image Equalization

    Directory of Open Access Journals (Sweden)

    Thierry Guillemot

    2016-06-01

    Full Text Available In this paper, we present the detailed algorithm of the Midway Image Equalization giving to a pair of images the same histogram while maintaining as much as possible their previous gray dynamics. The midway equalization is primarily designed for gray level images, but can be applied channel-wise to color images. This method is easy to implement, fast to compute, fully automatic and requires no parameter.

  15. The level of detail required in a deformable phantom to accurately perform quality assurance of deformable image registration

    Science.gov (United States)

    Saenz, Daniel L.; Kim, Hojin; Chen, Josephine; Stathakis, Sotirios; Kirby, Neil

    2016-09-01

    The primary purpose of the study was to determine how detailed deformable image registration (DIR) phantoms need to adequately simulate human anatomy and accurately assess the quality of DIR algorithms. In particular, how many distinct tissues are required in a phantom to simulate complex human anatomy? Pelvis and head-and-neck patient CT images were used for this study as virtual phantoms. Two data sets from each site were analyzed. The virtual phantoms were warped to create two pairs consisting of undeformed and deformed images. Otsu’s method was employed to create additional segmented image pairs of n distinct soft tissue CT number ranges (fat, muscle, etc). A realistic noise image was added to each image. Deformations were applied in MIM Software (MIM) and Velocity deformable multi-pass (DMP) and compared with the known warping. Images with more simulated tissue levels exhibit more contrast, enabling more accurate results. Deformation error (magnitude of the vector difference between known and predicted deformation) was used as a metric to evaluate how many CT number gray levels are needed for a phantom to serve as a realistic patient proxy. Stabilization of the mean deformation error was reached by three soft tissue levels for Velocity DMP and MIM, though MIM exhibited a persisting difference in accuracy between the discrete images and the unprocessed image pair. A minimum detail of three levels allows a realistic patient proxy for use with Velocity and MIM deformation algorithms.

  16. Gray matter heterotopias: MR and clinical features

    International Nuclear Information System (INIS)

    Moon, Tae Myung; Yoon, Jeong Hee; Chung, Chun Phil

    1995-01-01

    To evaluate types of gray matter heterotopias, associated brain anomalies, and its correlation with the patterns of seizure. We evaluated retrospectively 19 patients (male:female=10:9, mean age 21 years) with gray matter heterotopias on brain MRI. Using 1.0T superconducting MR unit, spin echo T1-, proton -density and T2-weighted images in axial, coronal and sagittal planes were obtained. Types of gray matter heterotopias were single subependymal in four patients, multiple subependymal in one, focal subcortical in eight, diffuse subcortical in two, mixed multiple subependymal and focal subcortical in four. Associated anomalies were seen in 11 patients: other neuronal migration anomalies in eight patients, corpus callosum agenesis in two, and combined holoprosencephaly and Dandy-Walker malformation in one. Fifteen patients had seizure. The patterns of seizure were not correlated with the types of heterotopias. In addition to subependymal, focal subcortical, and diffuse subcortical types, gray matter heterotopias included mixed variant of multiple subependymal and subcortical type. Schizencephaly was the most common form of accompanying anomalies, and patterns of seizure were not correlated with types of gray matter heterotopias, even though main clinical manifestation was seizure

  17. Bit-level quantum color image encryption scheme with quantum cross-exchange operation and hyper-chaotic system

    Science.gov (United States)

    Zhou, Nanrun; Chen, Weiwei; Yan, Xinyu; Wang, Yunqian

    2018-06-01

    In order to obtain higher encryption efficiency, a bit-level quantum color image encryption scheme by exploiting quantum cross-exchange operation and a 5D hyper-chaotic system is designed. Additionally, to enhance the scrambling effect, the quantum channel swapping operation is employed to swap the gray values of corresponding pixels. The proposed color image encryption algorithm has larger key space and higher security since the 5D hyper-chaotic system has more complex dynamic behavior, better randomness and unpredictability than those based on low-dimensional hyper-chaotic systems. Simulations and theoretical analyses demonstrate that the presented bit-level quantum color image encryption scheme outperforms its classical counterparts in efficiency and security.

  18. Female adolescents with severe substance and conduct problems have substantially less brain gray matter volume.

    Directory of Open Access Journals (Sweden)

    Manish S Dalwani

    Full Text Available Structural neuroimaging studies have demonstrated lower regional gray matter volume in adolescents with severe substance and conduct problems. These research studies, including ours, have generally focused on male-only or mixed-sex samples of adolescents with conduct and/or substance problems. Here we compare gray matter volume between female adolescents with severe substance and conduct problems and female healthy controls of similar ages.Female adolescents with severe substance and conduct problems will show significantly less gray matter volume in frontal regions critical to inhibition (i.e. dorsolateral prefrontal cortex and ventrolateral prefrontal cortex, conflict processing (i.e., anterior cingulate, valuation of expected outcomes (i.e., medial orbitofrontal cortex and the dopamine reward system (i.e. striatum.We conducted whole-brain voxel-based morphometric comparison of structural MR images of 22 patients (14-18 years with severe substance and conduct problems and 21 controls of similar age using statistical parametric mapping (SPM and voxel-based morphometric (VBM8 toolbox. We tested group differences in regional gray matter volume with analyses of covariance, adjusting for age and IQ at p<0.05, corrected for multiple comparisons at whole-brain cluster-level threshold.Female adolescents with severe substance and conduct problems compared to controls showed significantly less gray matter volume in right dorsolateral prefrontal cortex, left ventrolateral prefrontal cortex, medial orbitofrontal cortex, anterior cingulate, bilateral somatosensory cortex, left supramarginal gyrus, and bilateral angular gyrus. Considering the entire brain, patients had 9.5% less overall gray matter volume compared to controls.Female adolescents with severe substance and conduct problems in comparison to similarly aged female healthy controls showed substantially lower gray matter volume in brain regions involved in inhibition, conflict processing, valuation

  19. Discrimination of nitrogen fertilizer levels of tea plant (Camellia sinensis) based on hyperspectral imaging.

    Science.gov (United States)

    Wang, Yujie; Hu, Xin; Hou, Zhiwei; Ning, Jingming; Zhang, Zhengzhu

    2018-04-01

    Nitrogen (N) fertilizer plays an important role in tea plantation management, with significant impacts on the photosynthetic capacity, productivity and nutrition status of tea plants. The present study aimed to establish a method for the discrimination of N fertilizer levels using hyperspectral imaging technique. Spectral data were extracted from the region of interest, followed by the first derivative to reduce background noise. Five optimal wavelengths were selected by principal component analysis. Texture features were extracted from the images at optimal wavelengths by gray-level gradient co-occurrence matrix. Support vector machine (SVM) and extreme learning machine were used to build classification models based on spectral data, optimal wavelengths, texture features and data fusion, respectively. The SVM model using fused data gave the best performance with highest correct classification rate of 100% for prediction set. The overall results indicated that visible and near-infrared hyperspectral imaging combined with SVM were effective in discriminating N fertilizer levels of tea plants. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  20. Semantics by levels: An example for an image language

    International Nuclear Information System (INIS)

    Fasciano, M.; Levialdi, S.; Tortora, G.

    1984-01-01

    Ambiguities in formal language constructs may decrease both the understanding and the coding efficiency of a program. Within an image language, two semantic levels have been detected, corresponding to the lower level (pixel-based) and to the higher level (image-based). Denotational semantics has been used to define both levels within PIXAL (an image language) in order to enable the reader to visualize a concrete application of the semantic levels and their implications in a programming environment. This paper presents the semantics of different levels of conceptualization in the abstract formal description of an image language. The disambiguation of the meaning of special purpose constructs that imply either the elementary (pixels) level or the high image (array) level is naturally obtained by means of such semantic clauses. Perhaps non Von architectures on which hierarchical computations may be performed could also benefit from the use of semantic clauses to explicit the different levels where such computations are executed

  1. MODIS Level-3 Standard Mapped Image

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes chlorophyll-a concentration data from NASA's Aqua Spacecraft. Measurements are gathered by the Moderate Resolution Imaging...

  2. An enhanced fractal image denoising algorithm

    International Nuclear Information System (INIS)

    Lu Jian; Ye Zhongxing; Zou Yuru; Ye Ruisong

    2008-01-01

    In recent years, there has been a significant development in image denoising using fractal-based method. This paper presents an enhanced fractal predictive denoising algorithm for denoising the images corrupted by an additive white Gaussian noise (AWGN) by using quadratic gray-level function. Meanwhile, a quantization method for the fractal gray-level coefficients of the quadratic function is proposed to strictly guarantee the contractivity requirement of the enhanced fractal coding, and in terms of the quality of the fractal representation measured by PSNR, the enhanced fractal image coding using quadratic gray-level function generally performs better than the standard fractal coding using linear gray-level function. Based on this enhanced fractal coding, the enhanced fractal image denoising is implemented by estimating the fractal gray-level coefficients of the quadratic function of the noiseless image from its noisy observation. Experimental results show that, compared with other standard fractal-based image denoising schemes using linear gray-level function, the enhanced fractal denoising algorithm can improve the quality of the restored image efficiently

  3. The Internet And Gray Marketing

    OpenAIRE

    Soumava Bandyopadhyay

    2010-01-01

    The purpose of this conceptual paper is to investigate the nature, extent, and outcomes of gray marketing on the Internet.  We examined the current state of Internet-based gray marketing in several product categories and found the phenomenon to be on the rise.  Next, we developed a series of propositions to address evolving trends in online gray marketing, regarding actions of intermediaries and manufacturers, response by consumers, and outcomes on marketing strategy.

  4. A new level set model for cell image segmentation

    Science.gov (United States)

    Ma, Jing-Feng; Hou, Kai; Bao, Shang-Lian; Chen, Chun

    2011-02-01

    In this paper we first determine three phases of cell images: background, cytoplasm and nucleolus according to the general physical characteristics of cell images, and then develop a variational model, based on these characteristics, to segment nucleolus and cytoplasm from their relatively complicated backgrounds. In the meantime, the preprocessing obtained information of cell images using the OTSU algorithm is used to initialize the level set function in the model, which can speed up the segmentation and present satisfactory results in cell image processing.

  5. Gray Matter Hypertrophy and Thickening with Obstructive Sleep Apnea in Middle-aged and Older Adults.

    Science.gov (United States)

    Baril, Andrée-Ann; Gagnon, Katia; Brayet, Pauline; Montplaisir, Jacques; De Beaumont, Louis; Carrier, Julie; Lafond, Chantal; L'Heureux, Francis; Gagnon, Jean-François; Gosselin, Nadia

    2017-06-01

    Obstructive sleep apnea causes intermittent hypoxemia, hemodynamic fluctuations, and sleep fragmentation, all of which could damage cerebral gray matter that can be indirectly assessed by neuroimaging. To investigate whether markers of obstructive sleep apnea severity are associated with gray matter changes among middle-aged and older individuals. Seventy-one subjects (ages, 55-76 yr; apnea-hypopnea index, 0.2-96.6 events/h) were evaluated by magnetic resonance imaging. Two techniques were used: (1) voxel-based morphometry, which measures gray matter volume and concentration; and (2) FreeSurfer (an open source software suite) automated segmentation, which estimates the volume of predefined cortical/subcortical regions and cortical thickness. Regression analyses were performed between gray matter characteristics and markers of obstructive sleep apnea severity (hypoxemia, respiratory disturbances, and sleep fragmentation). Subjects had few symptoms, that is, sleepiness, depression, anxiety, and cognitive deficits. Although no association was found with voxel-based morphometry, FreeSurfer revealed increased gray matter with obstructive sleep apnea. Higher levels of hypoxemia correlated with increased volume and thickness of the left lateral prefrontal cortex as well as increased thickness of the right frontal pole, the right lateral parietal lobules, and the left posterior cingulate cortex. Respiratory disturbances positively correlated with right amygdala volume, and more severe sleep fragmentation was associated with increased thickness of the right inferior frontal gyrus. Gray matter hypertrophy and thickening were associated with hypoxemia, respiratory disturbances, and sleep fragmentation. These structural changes in a group of middle-aged and older individuals may represent adaptive/reactive brain mechanisms attributed to a presymptomatic stage of obstructive sleep apnea.

  6. Gray Matter Is Targeted in First-Attack Multiple Sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Schutzer, Steven E.; Angel, Thomas E.; Liu, Tao; Schepmoes, Athena A.; Xie, Fang; Bergquist, Jonas P.; Vecsei, Lazlo' ; Zadori, Denes; Camp, David G.; Holland, Bart K.; Smith, Richard D.; Coyle, Patricia K.

    2013-09-10

    The cause of multiple sclerosis (MS), its driving pathogenesis at the earliest stages, and what factors allow the first clinical attack to manifest remain unknown. Some imaging studies suggest gray rather than white matter may be involved early, and some postulate this may be predictive of developing MS. Other imaging studies are in conflict. To determine if there was objective molecular evidence of gray matter involvement in early MS we used high-resolution mass spectrometry to identify proteins in the cerebrospinal fluid (CSF) of first-attack MS patients (two independent groups) compared to established relapsing remitting (RR) MS and controls. We found that the CSF proteins in first-attack patients were differentially enriched for gray matter components (axon, neuron, synapse). Myelin components did not distinguish these groups. The results support that gray matter dysfunction is involved early in MS, and also may be integral for the initial clinical presentation.

  7. Serum vitamin D and hippocampal gray matter volume in schizophrenia.

    Science.gov (United States)

    Shivakumar, Venkataram; Kalmady, Sunil V; Amaresha, Anekal C; Jose, Dania; Narayanaswamy, Janardhanan C; Agarwal, Sri Mahavir; Joseph, Boban; Venkatasubramanian, Ganesan; Ravi, Vasanthapuram; Keshavan, Matcheri S; Gangadhar, Bangalore N

    2015-08-30

    Disparate lines of evidence including epidemiological and case-control studies have increasingly implicated vitamin D in the pathogenesis of schizophrenia. Vitamin D deficiency can lead to dysfunction of the hippocampus--a brain region hypothesized to be critically involved in schizophrenia. In this study, we examined for potential association between serum vitamin D level and hippocampal gray matter volume in antipsychotic-naïve or antipsychotic-free schizophrenia patients (n = 35). Serum vitamin D level was estimated using 25-OH vitamin D immunoassay. Optimized voxel-based morphometry was used to analyze 3-Tesla magnetic resonance imaging (MRI) (1-mm slice thickness). Ninety-seven percent of the schizophrenia patients (n = 34) had sub-optimal levels of serum vitamin D (83%, deficiency; 14%, insufficiency). A significant positive correlation was seen between vitamin D and regional gray matter volume in the right hippocampus after controlling for age, years of education and total intracranial volume (Montreal Neurological Institute (MNI) coordinates: x = 35, y = -18, z = -8; t = 4.34 pFWE(Corrected) = 0.018). These observations support a potential role of vitamin D deficiency in mediating hippocampal volume deficits, possibly through neurotrophic, neuroimmunomodulatory and glutamatergic effects. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. Grays Harbor Paper

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, B. [Grays Harbor Paper, Hoquiam, WA (United States)

    2009-07-01

    Wood waste biomass boilers are used at Grays Harbor Paper in Hoquiam, Washington. This presentation showed that large volumes of biomass are left after a traditional clearcut. The opportunities and challenges of collecting branches, tops and stumps from this wet coastal climate were outlined. The paper described some of the low-tech methods for picking up branches, stumps and woody debris. It included several photographs of custom logging machines for timber harvest, including a brush grapple slasher, a shearer shovel, chippers, grinders, slicesaws, trucks, trailers and caterpillar log loaders for handling slash. The slash recovery program relies on innovative harvesting machines that convert scattered logging slash into bundles that can be easily collected, transported, and stored for use in existing facilities that utilize wood fiber for fuel. figs.

  9. Why Does Hair Turn Gray?

    Science.gov (United States)

    ... out, but people with naturally lighter hair are just as likely to go gray. From the time a person notices a few gray hairs, it may take more than 10 years for all of that person's hair to turn ... really believe that this happens. Just in case, try not to freak out your ...

  10. Novel Amdovirus in Gray Foxes

    Science.gov (United States)

    Li, Linlin; Pesavento, Patricia A.; Woods, Leslie; Clifford, Deana L.; Luff, Jennifer; Wang, Chunlin

    2011-01-01

    We used viral metagenomics to identify a novel parvovirus in tissues of a gray fox (Urocyon cinereoargenteus). Nearly full genome characterization and phylogenetic analyses showed this parvovirus (provisionally named gray fox amdovirus) to be distantly related to Aleutian mink disease virus, representing the second viral species in the Amdovirus genus. PMID:22000359

  11. Cognitive Implications of Deep Gray Matter Iron in Multiple Sclerosis.

    Science.gov (United States)

    Fujiwara, E; Kmech, J A; Cobzas, D; Sun, H; Seres, P; Blevins, G; Wilman, A H

    2017-05-01

    Deep gray matter iron accumulation is increasingly recognized in association with multiple sclerosis and can be measured in vivo with MR imaging. The cognitive implications of this pathology are not well-understood, especially vis-à-vis deep gray matter atrophy. Our aim was to investigate the relationships between cognition and deep gray matter iron in MS by using 2 MR imaging-based iron-susceptibility measures. Forty patients with multiple sclerosis (relapsing-remitting, n = 16; progressive, n = 24) and 27 healthy controls were imaged at 4.7T by using the transverse relaxation rate and quantitative susceptibility mapping. The transverse relaxation rate and quantitative susceptibility mapping values and volumes (atrophy) of the caudate, putamen, globus pallidus, and thalamus were determined by multiatlas segmentation. Cognition was assessed with the Brief Repeatable Battery of Neuropsychological Tests. Relationships between cognition and deep gray matter iron were examined by hierarchic regressions. Compared with controls, patients showed reduced memory ( P processing speed ( P = .02) and smaller putamen ( P deep gray matter iron accumulation in the current multiple sclerosis cohort. Atrophy and iron accumulation in deep gray matter both have negative but separable relationships to cognition in multiple sclerosis. © 2017 by American Journal of Neuroradiology.

  12. Spinal Cord Gray Matter Atrophy in Amyotrophic Lateral Sclerosis.

    Science.gov (United States)

    Paquin, M-Ê; El Mendili, M M; Gros, C; Dupont, S M; Cohen-Adad, J; Pradat, P-F

    2018-01-01

    There is an emerging need for biomarkers to better categorize clinical phenotypes and predict progression in amyotrophic lateral sclerosis. This study aimed to quantify cervical spinal gray matter atrophy in amyotrophic lateral sclerosis and investigate its association with clinical disability at baseline and after 1 year. Twenty-nine patients with amyotrophic lateral sclerosis and 22 healthy controls were scanned with 3T MR imaging. Standard functional scale was recorded at the time of MR imaging and after 1 year. MR imaging data were processed automatically to measure the spinal cord, gray matter, and white matter cross-sectional areas. A statistical analysis assessed the difference in cross-sectional areas between patients with amyotrophic lateral sclerosis and controls, correlations between spinal cord and gray matter atrophy to clinical disability at baseline and at 1 year, and prediction of clinical disability at 1 year. Gray matter atrophy was more sensitive to discriminate patients with amyotrophic lateral sclerosis from controls ( P = .004) compared with spinal cord atrophy ( P = .02). Gray matter and spinal cord cross-sectional areas showed good correlations with clinical scores at baseline ( R = 0.56 for gray matter and R = 0.55 for spinal cord; P amyotrophic lateral sclerosis. © 2018 by American Journal of Neuroradiology.

  13. The ``gray cortex``: an early sign of stress fracture

    Energy Technology Data Exchange (ETDEWEB)

    Mulligan, M.E. [Dept. of Radiology, Univ. of Maryland Medical Center, Baltimore, MD (United States)

    1995-04-01

    The purpose of this report is to describe an early radiographic sign of stress fracture, the ``gray cortex.`` The imaging findings in three patients with tibial stress fractures were reviewed. The ``gray cortex`` sign was evident on the initial conventional radiographs in all three cases. It was prospectively reported as a sign of stress fracture in two patients and was evident on the initial radiographs (taken elsewhere) of the third patient, who was referred for additional workup of a possible neoplasm. Special imaging studies (technetium-99m bone scan, computed tomography, and magnetic resonance imaging) confirmed the diagnosis in all three cases. (orig.)

  14. The ''gray cortex'': an early sign of stress fracture

    International Nuclear Information System (INIS)

    Mulligan, M.E.

    1995-01-01

    The purpose of this report is to describe an early radiographic sign of stress fracture, the ''gray cortex.'' The imaging findings in three patients with tibial stress fractures were reviewed. The ''gray cortex'' sign was evident on the initial conventional radiographs in all three cases. It was prospectively reported as a sign of stress fracture in two patients and was evident on the initial radiographs (taken elsewhere) of the third patient, who was referred for additional workup of a possible neoplasm. Special imaging studies (technetium-99m bone scan, computed tomography, and magnetic resonance imaging) confirmed the diagnosis in all three cases. (orig.)

  15. Gray Matter Concentration Abnormality in Brains of Narcolepsy Patients

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Eun Yeon; Tae, Woo Suk; Kim, Sung Tae; Hong, Seung Bong [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2009-12-15

    To investigate gray matter concentration changes in the brains of narcoleptic patients. Twenty-nine narcoleptic patient with cataplexy and 29 age and sex-matched normal subjects (mean age, 31 years old) underwent volumetric MRIs. The MRIs were spatially normalized to a standard T1 template and subdivided into gray matter, white matter, and cerebrospinal fluid (CSF). These segmented images were then smoothed using a 12-mm full width at half maximum (FWHM) isotropic Gaussian kernel. An optimized voxel-based morphometry protocol was used to analyze brain tissue concentrations using SPM2 (statistical parametric mapping). A one-way analysis of variance was applied to the concentration analysis of gray matter images. Narcoleptics with cataplexy showed reduced gray matter concentration in bilateral thalami, left gyrus rectus, bilateral frontopolar gyri, bilateral short insular gyri, bilateral superior frontal gyri, and right superior temporal and left inferior temporal gyri compared to normal subjects (uncorrected p < 0.001). Furthermore, small volume correction revealed gray matter concentration reduction in bilateral nuclei accumbens, hypothalami, and thalami (false discovery rate corrected p < 0.05). Gray matter concentration reductions were observed in brain regions related to excessive daytime sleepiness, cognition, attention, and memory in narcoleptics with cataplexy

  16. Gray Matter Concentration Abnormality in Brains of Narcolepsy Patients

    International Nuclear Information System (INIS)

    Joo, Eun Yeon; Tae, Woo Suk; Kim, Sung Tae; Hong, Seung Bong

    2009-01-01

    To investigate gray matter concentration changes in the brains of narcoleptic patients. Twenty-nine narcoleptic patient with cataplexy and 29 age and sex-matched normal subjects (mean age, 31 years old) underwent volumetric MRIs. The MRIs were spatially normalized to a standard T1 template and subdivided into gray matter, white matter, and cerebrospinal fluid (CSF). These segmented images were then smoothed using a 12-mm full width at half maximum (FWHM) isotropic Gaussian kernel. An optimized voxel-based morphometry protocol was used to analyze brain tissue concentrations using SPM2 (statistical parametric mapping). A one-way analysis of variance was applied to the concentration analysis of gray matter images. Narcoleptics with cataplexy showed reduced gray matter concentration in bilateral thalami, left gyrus rectus, bilateral frontopolar gyri, bilateral short insular gyri, bilateral superior frontal gyri, and right superior temporal and left inferior temporal gyri compared to normal subjects (uncorrected p < 0.001). Furthermore, small volume correction revealed gray matter concentration reduction in bilateral nuclei accumbens, hypothalami, and thalami (false discovery rate corrected p < 0.05). Gray matter concentration reductions were observed in brain regions related to excessive daytime sleepiness, cognition, attention, and memory in narcoleptics with cataplexy

  17. A new level set model for cell image segmentation

    International Nuclear Information System (INIS)

    Ma Jing-Feng; Chen Chun; Hou Kai; Bao Shang-Lian

    2011-01-01

    In this paper we first determine three phases of cell images: background, cytoplasm and nucleolus according to the general physical characteristics of cell images, and then develop a variational model, based on these characteristics, to segment nucleolus and cytoplasm from their relatively complicated backgrounds. In the meantime, the preprocessing obtained information of cell images using the OTSU algorithm is used to initialize the level set function in the model, which can speed up the segmentation and present satisfactory results in cell image processing. (cross-disciplinary physics and related areas of science and technology)

  18. Acceptable levels of digital image compression in chest radiology

    International Nuclear Information System (INIS)

    Smith, I.

    2000-01-01

    The introduction of picture archival and communications systems (PACS) and teleradiology has prompted an examination of techniques that optimize the storage capacity and speed of digital storage and distribution networks. The general acceptance of the move to replace conventional screen-film capture with computed radiography (CR) is an indication that clinicians within the radiology community are willing to accept images that have been 'compressed'. The question to be answered, therefore, is what level of compression is acceptable. The purpose of the present study is to provide an assessment of the ability of a group of imaging professionals to determine whether an image has been compressed. To undertake this study a single mobile chest image, selected for the presence of some subtle pathology in the form of a number of septal lines in both costphrenic angles, was compressed to levels of 10:1, 20:1 and 30:1. These images were randomly ordered and shown to the observers for interpretation. Analysis of the responses indicates that in general it was not possible to distinguish the original image from its compressed counterparts. Furthermore, a preference appeared to be shown for images that have undergone low levels of compression. This preference can most likely be attributed to the 'de-noising' effect of the compression algorithm at low levels. Copyright (1999) Blackwell Science Pty. Ltd

  19. The Gray whale: Eschrichtius robustus

    National Research Council Canada - National Science Library

    Jones, Mary Lou; Leatherwood, Stephen; Swartz, Steven L

    1984-01-01

    .... Section II documents historical aspects of gray whale exploitation and the economic importance of these whales to humans, beginning with aboriginal societies in Asia and North America, and leading...

  20. Niobium in gray cast iron

    International Nuclear Information System (INIS)

    Castello Branco, C.H.; Beckert, E.A.

    1984-03-01

    The potential for utilization of niobium in gray cast iron is appraised and reviewed. Experiments described in literature indicate that niobium provides structural refinement of the eutectic cells and also promotes pearlite formation. (Author) [pt

  1. Antecedents of Gray Divorce: A Life Course Perspective.

    Science.gov (United States)

    Lin, I-Fen; Brown, Susan L; Wright, Matthew R; Hammersmith, Anna M

    2016-12-16

    Increasingly, older adults are experiencing divorce, yet little is known about the risk factors associated with divorce after age 50 (termed "gray divorce"). Guided by a life course perspective, our study examined whether key later life turning points are related to gray divorce. We used data from the 1998-2012 Health and Retirement Study to conduct a prospective, couple-level discrete-time event history analysis of the antecedents of gray divorce. Our models incorporated key turning points (empty nest, retirement, and poor health) as well as demographic characteristics and economic resources. Contrary to our expectations, the onset of an empty nest, the wife's or husband's retirement, and the wife's or husband's chronic conditions were unrelated to the likelihood of gray divorce. Rather, factors traditionally associated with divorce among younger adults were also salient for older adults. Marital duration, marital quality, home ownership, and wealth were negatively related to the risk of gray divorce. Gray divorce is especially likely to occur among couples who are socially and economically disadvantaged, raising new questions about the consequences of gray divorce for individual health and well-being. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Level set method for image segmentation based on moment competition

    Science.gov (United States)

    Min, Hai; Wang, Xiao-Feng; Huang, De-Shuang; Jin, Jing; Wang, Hong-Zhi; Li, Hai

    2015-05-01

    We propose a level set method for image segmentation which introduces the moment competition and weakly supervised information into the energy functional construction. Different from the region-based level set methods which use force competition, the moment competition is adopted to drive the contour evolution. Here, a so-called three-point labeling scheme is proposed to manually label three independent points (weakly supervised information) on the image. Then the intensity differences between the three points and the unlabeled pixels are used to construct the force arms for each image pixel. The corresponding force is generated from the global statistical information of a region-based method and weighted by the force arm. As a result, the moment can be constructed and incorporated into the energy functional to drive the evolving contour to approach the object boundary. In our method, the force arm can take full advantage of the three-point labeling scheme to constrain the moment competition. Additionally, the global statistical information and weakly supervised information are successfully integrated, which makes the proposed method more robust than traditional methods for initial contour placement and parameter setting. Experimental results with performance analysis also show the superiority of the proposed method on segmenting different types of complicated images, such as noisy images, three-phase images, images with intensity inhomogeneity, and texture images.

  3. Low level cloud motion vectors from Kalpana-1 visible images

    Indian Academy of Sciences (India)

    . In this paper, an attempt has been made to retrieve low-level cloud motion vectors using Kalpana-1 visible (VIS) images at every half an hour. The VIS channel provides better detection of low level clouds, which remain obscure in thermal IR ...

  4. Data compression of scanned halftone images

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Jensen, Kim S.

    1994-01-01

    with the halftone grid, and converted to a gray level representation. A new digital description of (halftone) grids has been developed for this purpose. The gray level values are coded according to a scheme based on states derived from a segmentation of gray values. To enable real-time processing of high resolution...... scanner output, the coding has been parallelized and implemented on a transputer system. For comparison, the test image was coded using existing (lossless) methods giving compression rates of 2-7. The best of these, a combination of predictive and binary arithmetic coding was modified and optimized...

  5. New false color mapping for image fusion

    NARCIS (Netherlands)

    Toet, A.; Walraven, J.

    1996-01-01

    A pixel based colour mapping algorithm is presented that produces a fused false colour rendering of two gray level images representing different sensor modalities. The result-ing fused false colour images have a higher information content than each of the original images and retain sensor-specific

  6. SENTINEL-2 Level 1 Products and Image Processing Performances

    Science.gov (United States)

    Baillarin, S. J.; Meygret, A.; Dechoz, C.; Petrucci, B.; Lacherade, S.; Tremas, T.; Isola, C.; Martimort, P.; Spoto, F.

    2012-07-01

    In partnership with the European Commission and in the frame of the Global Monitoring for Environment and Security (GMES) program, the European Space Agency (ESA) is developing the Sentinel-2 optical imaging mission devoted to the operational monitoring of land and coastal areas. The Sentinel-2 mission is based on a satellites constellation deployed in polar sun-synchronous orbit. While ensuring data continuity of former SPOT and LANDSAT multi-spectral missions, Sentinel-2 will also offer wide improvements such as a unique combination of global coverage with a wide field of view (290 km), a high revisit (5 days with two satellites), a high resolution (10 m, 20 m and 60 m) and multi-spectral imagery (13 spectral bands in visible and shortwave infra-red domains). In this context, the Centre National d'Etudes Spatiales (CNES) supports ESA to define the system image products and to prototype the relevant image processing techniques. This paper offers, first, an overview of the Sentinel-2 system and then, introduces the image products delivered by the ground processing: the Level-0 and Level-1A are system products which correspond to respectively raw compressed and uncompressed data (limited to internal calibration purposes), the Level-1B is the first public product: it comprises radiometric corrections (dark signal, pixels response non uniformity, crosstalk, defective pixels, restoration, and binning for 60 m bands); and an enhanced physical geometric model appended to the product but not applied, the Level-1C provides ortho-rectified top of atmosphere reflectance with a sub-pixel multi-spectral and multi-date registration; a cloud and land/water mask is associated to the product. Note that the cloud mask also provides an indication about cirrus. The ground sampling distance of Level-1C product will be 10 m, 20 m or 60 m according to the band. The final Level-1C product is tiled following a pre-defined grid of 100x100 km2, based on UTM/WGS84 reference frame. The

  7. SENTINEL-2 LEVEL 1 PRODUCTS AND IMAGE PROCESSING PERFORMANCES

    Directory of Open Access Journals (Sweden)

    S. J. Baillarin

    2012-07-01

    Full Text Available In partnership with the European Commission and in the frame of the Global Monitoring for Environment and Security (GMES program, the European Space Agency (ESA is developing the Sentinel-2 optical imaging mission devoted to the operational monitoring of land and coastal areas. The Sentinel-2 mission is based on a satellites constellation deployed in polar sun-synchronous orbit. While ensuring data continuity of former SPOT and LANDSAT multi-spectral missions, Sentinel-2 will also offer wide improvements such as a unique combination of global coverage with a wide field of view (290 km, a high revisit (5 days with two satellites, a high resolution (10 m, 20 m and 60 m and multi-spectral imagery (13 spectral bands in visible and shortwave infra-red domains. In this context, the Centre National d'Etudes Spatiales (CNES supports ESA to define the system image products and to prototype the relevant image processing techniques. This paper offers, first, an overview of the Sentinel-2 system and then, introduces the image products delivered by the ground processing: the Level-0 and Level-1A are system products which correspond to respectively raw compressed and uncompressed data (limited to internal calibration purposes, the Level-1B is the first public product: it comprises radiometric corrections (dark signal, pixels response non uniformity, crosstalk, defective pixels, restoration, and binning for 60 m bands; and an enhanced physical geometric model appended to the product but not applied, the Level-1C provides ortho-rectified top of atmosphere reflectance with a sub-pixel multi-spectral and multi-date registration; a cloud and land/water mask is associated to the product. Note that the cloud mask also provides an indication about cirrus. The ground sampling distance of Level-1C product will be 10 m, 20 m or 60 m according to the band. The final Level-1C product is tiled following a pre-defined grid of 100x100 km2, based on UTM/WGS84 reference frame

  8. Low-level processing for real-time image analysis

    Science.gov (United States)

    Eskenazi, R.; Wilf, J. M.

    1979-01-01

    A system that detects object outlines in television images in real time is described. A high-speed pipeline processor transforms the raw image into an edge map and a microprocessor, which is integrated into the system, clusters the edges, and represents them as chain codes. Image statistics, useful for higher level tasks such as pattern recognition, are computed by the microprocessor. Peak intensity and peak gradient values are extracted within a programmable window and are used for iris and focus control. The algorithms implemented in hardware and the pipeline processor architecture are described. The strategy for partitioning functions in the pipeline was chosen to make the implementation modular. The microprocessor interface allows flexible and adaptive control of the feature extraction process. The software algorithms for clustering edge segments, creating chain codes, and computing image statistics are also discussed. A strategy for real time image analysis that uses this system is given.

  9. Training Methods for Image Noise Level Estimation on Wavelet Components

    Directory of Open Access Journals (Sweden)

    A. De Stefano

    2004-12-01

    Full Text Available The estimation of the standard deviation of noise contaminating an image is a fundamental step in wavelet-based noise reduction techniques. The method widely used is based on the mean absolute deviation (MAD. This model-based method assumes specific characteristics of the noise-contaminated image component. Three novel and alternative methods for estimating the noise standard deviation are proposed in this work and compared with the MAD method. Two of these methods rely on a preliminary training stage in order to extract parameters which are then used in the application stage. The sets used for training and testing, 13 and 5 images, respectively, are fully disjoint. The third method assumes specific statistical distributions for image and noise components. Results showed the prevalence of the training-based methods for the images and the range of noise levels considered.

  10. Magnetic resonance imaging of the temporomandibular joint

    International Nuclear Information System (INIS)

    Nah, Kyung Soo

    1999-01-01

    To find out the best imaging parameters for the diagnosis of disc in MRI imaging. Compare the diagnostic quality of the disc among the T1, PD and T2 images of same patients (12 joints, 223 images) by visual (I-IV grades) and gray level measurement (pre- and infra-discal area) method. PD images showed best results with 43.7% of the images belonging to grade III (good) and with statistically significant higher difference of the gray levels at pre- and infra-discal areas. But there were no grade IV (excellent) images. PD images are best method among T1, PD and T2 images in diagnosing the disc but since there were no excellent images further imaging parameters should be studied for better images.

  11. Shape-based grey-level image interpolation

    International Nuclear Information System (INIS)

    Keh-Shih Chuang; Chun-Yuan Chen; Ching-Kai Yeh

    1999-01-01

    The three-dimensional (3D) object data obtained from a CT scanner usually have unequal sampling frequencies in the x-, y- and z-directions. Generally, the 3D data are first interpolated between slices to obtain isotropic resolution, reconstructed, then operated on using object extraction and display algorithms. The traditional grey-level interpolation introduces a layer of intermediate substance and is not suitable for objects that are very different from the opposite background. The shape-based interpolation method transfers a pixel location to a parameter related to the object shape and the interpolation is performed on that parameter. This process is able to achieve a better interpolation but its application is limited to binary images only. In this paper, we present an improved shape-based interpolation method for grey-level images. The new method uses a polygon to approximate the object shape and performs the interpolation using polygon vertices as references. The binary images representing the shape of the object were first generated via image segmentation on the source images. The target object binary image was then created using regular shape-based interpolation. The polygon enclosing the object for each slice can be generated from the shape of that slice. We determined the relative location in the source slices of each pixel inside the target polygon using the vertices of a polygon as the reference. The target slice grey-level was interpolated from the corresponding source image pixels. The image quality of this interpolation method is better and the mean squared difference is smaller than with traditional grey-level interpolation. (author)

  12. Bi-level image compression with tree coding

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren

    1996-01-01

    Presently, tree coders are the best bi-level image coders. The current ISO standard, JBIG, is a good example. By organising code length calculations properly a vast number of possible models (trees) can be investigated within reasonable time prior to generating code. Three general-purpose coders...... are constructed by this principle. A multi-pass free tree coding scheme produces superior compression results for all test images. A multi-pass fast free template coding scheme produces much better results than JBIG for difficult images, such as halftonings. Rissanen's algorithm `Context' is presented in a new...

  13. Prefrontal gray matter volume mediates genetic risks for obesity.

    Science.gov (United States)

    Opel, N; Redlich, R; Kaehler, C; Grotegerd, D; Dohm, K; Heindel, W; Kugel, H; Thalamuthu, A; Koutsouleris, N; Arolt, V; Teuber, A; Wersching, H; Baune, B T; Berger, K; Dannlowski, U

    2017-05-01

    Genetic and neuroimaging research has identified neurobiological correlates of obesity. However, evidence for an integrated model of genetic risk and brain structural alterations in the pathophysiology of obesity is still absent. Here we investigated the relationship between polygenic risk for obesity, gray matter structure and body mass index (BMI) by the use of univariate and multivariate analyses in two large, independent cohorts (n=330 and n=347). Higher BMI and higher polygenic risk for obesity were significantly associated with medial prefrontal gray matter decrease, and prefrontal gray matter was further shown to significantly mediate the effect of polygenic risk for obesity on BMI in both samples. Building on this, the successful individualized prediction of BMI by means of multivariate pattern classification algorithms trained on whole-brain imaging data and external validations in the second cohort points to potential clinical applications of this imaging trait marker.

  14. Generative complexity of Gray-Scott model

    Science.gov (United States)

    Adamatzky, Andrew

    2018-03-01

    In the Gray-Scott reaction-diffusion system one reactant is constantly fed in the system, another reactant is reproduced by consuming the supplied reactant and also converted to an inert product. The rate of feeding one reactant in the system and the rate of removing another reactant from the system determine configurations of concentration profiles: stripes, spots, waves. We calculate the generative complexity-a morphological complexity of concentration profiles grown from a point-wise perturbation of the medium-of the Gray-Scott system for a range of the feeding and removal rates. The morphological complexity is evaluated using Shannon entropy, Simpson diversity, approximation of Lempel-Ziv complexity, and expressivity (Shannon entropy divided by space-filling). We analyse behaviour of the systems with highest values of the generative morphological complexity and show that the Gray-Scott systems expressing highest levels of the complexity are composed of the wave-fragments (similar to wave-fragments in sub-excitable media) and travelling localisations (similar to quasi-dissipative solitons and gliders in Conway's Game of Life).

  15. Image quality enhancement in low-light-level ghost imaging using modified compressive sensing method

    Science.gov (United States)

    Shi, Xiaohui; Huang, Xianwei; Nan, Suqin; Li, Hengxing; Bai, Yanfeng; Fu, Xiquan

    2018-04-01

    Detector noise has a significantly negative impact on ghost imaging at low light levels, especially for existing recovery algorithm. Based on the characteristics of the additive detector noise, a method named modified compressive sensing ghost imaging is proposed to reduce the background imposed by the randomly distributed detector noise at signal path. Experimental results show that, with an appropriate choice of threshold value, modified compressive sensing ghost imaging algorithm can dramatically enhance the contrast-to-noise ratio of the object reconstruction significantly compared with traditional ghost imaging and compressive sensing ghost imaging methods. The relationship between the contrast-to-noise ratio of the reconstruction image and the intensity ratio (namely, the average signal intensity to average noise intensity ratio) for the three reconstruction algorithms are also discussed. This noise suppression imaging technique will have great applications in remote-sensing and security areas.

  16. Medial frontal white and gray matter contributions to general intelligence.

    Directory of Open Access Journals (Sweden)

    Toshiyuki Ohtani

    Full Text Available The medial orbitofrontal cortex (mOFC and rostral anterior cingulate cortex (rACC are part of a wider neural network that plays an important role in general intelligence and executive function. We used structural brain imaging to quantify magnetic resonance gray matter volume and diffusion tensor white matter integrity of the mOFC-rACC network in 26 healthy participants who also completed neuropsychological tests of intellectual abilities and executive function. Stochastic tractography, the most effective Diffusion Tensor Imaging method for examining white matter connections between adjacent gray matter regions, was employed to assess the integrity of mOFC-rACC pathways. Fractional anisotropy (FA, which reflects the integrity of white matter connections, was calculated. Results indicated that higher intelligence correlated with greater gray matter volumes for both mOFC and rACC, as well as with increased FA for left posterior mOFC-rACC connectivity. Hierarchical regression analyses revealed that DTI-derived FA of left posterior mOFC-rACC uniquely accounted for 29%-34% of the variance in IQ, in comparison to 11%-16% uniquely explained by gray matter volume of the left rACC. Together, left rACC gray matter volume and white matter connectivity between left posterior mOFC and rACC accounted for up to 50% of the variance in general intelligence. This study is to our knowledge the first to examine white matter connectivity between OFC and ACC, two gray matter regions of interests that are very close in physical proximity, and underscores the important independent contributions of variations in rACC gray matter volume and mOFC-rACC white matter connectivity to individual differences in general intelligence.

  17. Advanced gray rod control assembly

    Science.gov (United States)

    Drudy, Keith J; Carlson, William R; Conner, Michael E; Goldenfield, Mark; Hone, Michael J; Long, Jr., Carroll J; Parkinson, Jerod; Pomirleanu, Radu O

    2013-09-17

    An advanced gray rod control assembly (GRCA) for a nuclear reactor. The GRCA provides controlled insertion of gray rod assemblies into the reactor, thereby controlling the rate of power produced by the reactor and providing reactivity control at full power. Each gray rod assembly includes an elongated tubular member, a primary neutron-absorber disposed within the tubular member said neutron-absorber comprising an absorber material, preferably tungsten, having a 2200 m/s neutron absorption microscopic capture cross-section of from 10 to 30 barns. An internal support tube can be positioned between the primary absorber and the tubular member as a secondary absorber to enhance neutron absorption, absorber depletion, assembly weight, and assembly heat transfer characteristics.

  18. Grays River Watershed Geomorphic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Geist, David R

    2005-04-30

    This investigation, completed for the Pacific Northwest National Laboratory (PNNL), is part of the Grays River Watershed and Biological Assessment commissioned by Bonneville Power Administration under project number 2003-013-00 to assess impacts on salmon habitat in the upper Grays River watershed and present recommendations for habitat improvement. This report presents the findings of the geomorphic assessment and is intended to support the overall PNNL project by evaluating the following: The effects of historical and current land use practices on erosion and sedimentation within the channel network The ways in which these effects have influenced the sediment budget of the upper watershed The resulting responses in the main stem Grays River upstream of State Highway 4 The past and future implications for salmon habitat.

  19. SuperPixel based mid-level image description for image recognition

    NARCIS (Netherlands)

    Tasli, H.E.; Sicre, R.; Gevers, T.

    2015-01-01

    This study proposes a mid-level feature descriptor and aims to validate improvement on image classification and retrieval tasks. In this paper, we propose a method to explore the conventional feature extraction techniques in the image classification pipeline from a different perspective where

  20. A deep level set method for image segmentation

    OpenAIRE

    Tang, Min; Valipour, Sepehr; Zhang, Zichen Vincent; Cobzas, Dana; MartinJagersand

    2017-01-01

    This paper proposes a novel image segmentation approachthat integrates fully convolutional networks (FCNs) with a level setmodel. Compared with a FCN, the integrated method can incorporatesmoothing and prior information to achieve an accurate segmentation.Furthermore, different than using the level set model as a post-processingtool, we integrate it into the training phase to fine-tune the FCN. Thisallows the use of unlabeled data during training in a semi-supervisedsetting. Using two types o...

  1. Shape-based interpolation of multidimensional grey-level images

    International Nuclear Information System (INIS)

    Grevera, G.J.; Udupa, J.K.

    1996-01-01

    Shape-based interpolation as applied to binary images causes the interpolation process to be influenced by the shape of the object. It accomplishes this by first applying a distance transform to the data. This results in the creation of a grey-level data set in which the value at each point represents the minimum distance from that point to the surface of the object. (By convention, points inside the object are assigned positive values; points outside are assigned negative values.) This distance transformed data set is then interpolated using linear or higher-order interpolation and is then thresholded at a distance value of zero to produce the interpolated binary data set. In this paper, the authors describe a new method that extends shape-based interpolation to grey-level input data sets. This generalization consists of first lifting the n-dimensional (n-D) image data to represent it as a surface, or equivalently as a binary image, in an (n + 1)-dimensional [(n + 1)-D] space. The binary shape-based method is then applied to this image to create an (n + 1)-D binary interpolated image. Finally, this image is collapsed (inverse of lifting) to create the n-D interpolated grey-level data set. The authors have conducted several evaluation studies involving patient computed tomography (CT) and magnetic resonance (MR) data as well as mathematical phantoms. They all indicate that the new method produces more accurate results than commonly used grey-level linear interpolation methods, although at the cost of increased computation

  2. Mapping Gray Matter Development: Implications for Typical Development and Vulnerability to Psychopathology

    Science.gov (United States)

    Gogtay, Nitin; Thompson, Paul M.

    2010-01-01

    Recent studies with brain magnetic resonance imaging (MRI) have scanned large numbers of children and adolescents repeatedly over time, as their brains develop, tracking volumetric changes in gray and white matter in remarkable detail. Focusing on gray matter changes specifically, here we explain how earlier studies using lobar volumes of specific…

  3. Regional Gray Matter Volume Deficits in Adolescents with First-Episode Psychosis

    Science.gov (United States)

    Janssen, Joost; Parellada, Mara; Moreno, Dolores; Graell, Montserrat; Fraguas, David; Zabala, Arantzazu; Vazquez, Veronica Garcia; Desco, Manuel; Arango, Celso

    2008-01-01

    The regional gray matter volumes of adolescents with first-episode psychosis are compared with those of a control group. Magnetic resonance imaging was conducted on 70 patients with early onset FEP and on 51 individuals without FEP. Findings revealed that volume deficits in the left medial frontal gray matter were common in individuals with…

  4. Digital image processing for real-time neutron radiography and its applications

    International Nuclear Information System (INIS)

    Fujine, Shigenori

    1989-01-01

    The present paper describes several digital image processing approaches for the real-time neutron radiography (neutron television-NTV), such as image integration, adaptive smoothing and image enhancement, which have beneficial effects on image improvements, and also describes how to use these techniques for applications. Details invisible in direct images of NTV are able to be revealed by digital image processing, such as reversed image, gray level correction, gray scale transformation, contoured image, subtraction technique, pseudo color display and so on. For real-time application a contouring operation and an averaging approach can also be utilized effectively. (author)

  5. Altered Gray Matter Volume and Resting-State Connectivity in Individuals With Internet Gaming Disorder: A Voxel-Based Morphometry and Resting-State Functional Magnetic Resonance Imaging Study

    Science.gov (United States)

    Seok, Ji-Woo; Sohn, Jin-Hun

    2018-01-01

    Neuroimaging studies on the characteristics of individuals with Internet gaming disorder (IGD) have been accumulating due to growing concerns regarding the psychological and social problems associated with Internet use. However, relatively little is known about the brain characteristics underlying IGD, such as the associated functional connectivity and structure. The aim of this study was to investigate alterations in gray matter (GM) volume and functional connectivity during resting state in individuals with IGD using voxel-based morphometry and a resting-state connectivity analysis. The participants included 20 individuals with IGD and 20 age- and sex-matched healthy controls. Resting-state functional and structural images were acquired for all participants using 3 T magnetic resonance imaging. We also measured the severity of IGD and impulsivity using psychological scales. The results show that IGD severity was positively correlated with GM volume in the left caudate (p < 0.05, corrected for multiple comparisons), and negatively associated with functional connectivity between the left caudate and the right middle frontal gyrus (p < 0.05, corrected for multiple comparisons). This study demonstrates that IGD is associated with neuroanatomical changes in the right middle frontal cortex and the left caudate. These are important brain regions for reward and cognitive control processes, and structural and functional abnormalities in these regions have been reported for other addictions, such as substance abuse and pathological gambling. The findings suggest that structural deficits and resting-state functional impairments in the frontostriatal network may be associated with IGD and provide new insights into the underlying neural mechanisms of IGD. PMID:29636704

  6. Altered Gray Matter Volume and Resting-State Connectivity in Individuals With Internet Gaming Disorder: A Voxel-Based Morphometry and Resting-State Functional Magnetic Resonance Imaging Study

    Directory of Open Access Journals (Sweden)

    Ji-Woo Seok

    2018-03-01

    Full Text Available Neuroimaging studies on the characteristics of individuals with Internet gaming disorder (IGD have been accumulating due to growing concerns regarding the psychological and social problems associated with Internet use. However, relatively little is known about the brain characteristics underlying IGD, such as the associated functional connectivity and structure. The aim of this study was to investigate alterations in gray matter (GM volume and functional connectivity during resting state in individuals with IGD using voxel-based morphometry and a resting-state connectivity analysis. The participants included 20 individuals with IGD and 20 age- and sex-matched healthy controls. Resting-state functional and structural images were acquired for all participants using 3 T magnetic resonance imaging. We also measured the severity of IGD and impulsivity using psychological scales. The results show that IGD severity was positively correlated with GM volume in the left caudate (p < 0.05, corrected for multiple comparisons, and negatively associated with functional connectivity between the left caudate and the right middle frontal gyrus (p < 0.05, corrected for multiple comparisons. This study demonstrates that IGD is associated with neuroanatomical changes in the right middle frontal cortex and the left caudate. These are important brain regions for reward and cognitive control processes, and structural and functional abnormalities in these regions have been reported for other addictions, such as substance abuse and pathological gambling. The findings suggest that structural deficits and resting-state functional impairments in the frontostriatal network may be associated with IGD and provide new insights into the underlying neural mechanisms of IGD.

  7. Lossless Image Compression Based on Multiple-Tables Arithmetic Coding

    Directory of Open Access Journals (Sweden)

    Rung-Ching Chen

    2009-01-01

    Full Text Available This paper is intended to present a lossless image compression method based on multiple-tables arithmetic coding (MTAC method to encode a gray-level image f. First, the MTAC method employs a median edge detector (MED to reduce the entropy rate of f. The gray levels of two adjacent pixels in an image are usually similar. A base-switching transformation approach is then used to reduce the spatial redundancy of the image. The gray levels of some pixels in an image are more common than those of others. Finally, the arithmetic encoding method is applied to reduce the coding redundancy of the image. To promote high performance of the arithmetic encoding method, the MTAC method first classifies the data and then encodes each cluster of data using a distinct code table. The experimental results show that, in most cases, the MTAC method provides a higher efficiency in use of storage space than the lossless JPEG2000 does.

  8. The Picture of Dorian Gray

    NARCIS (Netherlands)

    Wilde, Oscar

    2005-01-01

    On its first publication The Picture of Dorian Gray was regarded as dangerously modern in its depiction of fin-de-sicle decadence. In this updated version of the Faust story, the tempter is Lord Henry Wotton, who lives selfishly for amoral pleasure; Dorian's good angel is the portrait painter Basil

  9. Paulette Gray, Ph.D.

    Science.gov (United States)

    Paulette S. Gray, Ph.D. is the Director for the Division of Extramural Activities (DEA). As the director of the division, she is responsible for the overall scientific, fiscal, and administrative management of the division, including broad strategic planning, development, implementation, and evaluation.

  10. Tsenseerimata Dorian Gray? / Udo Uibo

    Index Scriptorium Estoniae

    Uibo, Udo, 1956-

    2011-01-01

    Harvardi ülikooli kirjastus üllitas 2011. a. kevadel Oscar Wilde'i ainsaks jäänud romaani "Dorian Gray portree" esialgse versiooni, mis on varustatud toimetaja Nicholas Frankeli põhjalike kommentaaridega ja kus eessõna manifesteerib jõuliselt autori esteetilisi vaateid

  11. Longitudinal Study of Gray Matter Changes in Parkinson Disease.

    Science.gov (United States)

    Jia, X; Liang, P; Li, Y; Shi, L; Wang, D; Li, K

    2015-12-01

    The pathology of Parkinson disease leads to morphological brain volume changes. So far, the progressive gray matter volume change across time specific to patients with Parkinson disease compared controls remains unclear. Our aim was to investigate the pattern of gray matter changes in patients with Parkinson disease and to explore the progressive gray matter volume change specific to patients with Parkinson disease with disease progression by using voxel-based morphometry analysis. Longitudinal cognitive assessment and structural MR imaging of 89 patients with Parkinson disease (62 men) and 55 healthy controls (33 men) were from the Parkinson's Progression Markers Initiative data base, including the initial baseline and 12-month follow-up data. Two-way analysis of covariance was performed with covariates of age, sex, years of education, imaging data from multiple centers, and total intracranial volume by using Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra tool from SPM8 software. Gray matter volume changes for patients with Parkinson disease were detected with decreased gray matter volume in the frontotemporoparietal areas and the bilateral caudate, with increased gray matter volume in the bilateral limbic/paralimbic areas, medial globus pallidus/putamen, and the right occipital cortex compared with healthy controls. Progressive gray matter volume decrease in the bilateral caudate was found for both patients with Parkinson disease and healthy controls, and this caudate volume was positively associated with cognitive ability for both groups. The progressive gray matter volume increase specific to the patients with Parkinson disease was identified close to the left ventral lateral nucleus of thalamus, and a positive relationship was found between the thalamic volume and the tremor scores in a subgroup with tremor-dominant patients with Parkinson disease. The observed progressive changes in gray matter volume in Parkinson disease may provide

  12. Gray QB-sing-faced version 2 (SF2) open environment test report

    Energy Technology Data Exchange (ETDEWEB)

    Plummer, J. [Savannah River Site (SRS), Aiken, SC (United States); Immel, D. [Savannah River Site (SRS), Aiken, SC (United States); Bobbitt, J. [Savannah River Site (SRS), Aiken, SC (United States); Negron, M. [Savannah River Site (SRS), Aiken, SC (United States)

    2015-02-16

    This report details the design upgrades incorporated into the new version of the GrayQbTM SF2 device and the characterization testing of this upgraded device. Results from controlled characterization testing in the Savannah River National Laboratory (SRNL) R&D Engineering Imaging and Radiation Lab (IRL) and the Savannah River Site (SRS) Health Physics Instrument Calibration Laboratory (HPICL) is presented, as well as results from the open environment field testing performed in the E-Area Low Level Waste Storage Area. Resultant images presented in this report were generated using the SRNL developed Radiation Analyzer (RAzerTM) software program which overlays the radiation contour images onto the visual image of the location being surveyed.

  13. Evaluation of Subependymal Gray Matter Heterotopias on Fetal MRI.

    Science.gov (United States)

    Nagaraj, U D; Peiro, J L; Bierbrauer, K S; Kline-Fath, B M

    2016-04-01

    Subependymal grey matter heterotopias are seen in a high proportion of children with Chiari II malformation and are potentially clinically relevant. However, despite its growing use, there is little in the literature describing its detection on fetal MRI. Our aim was to evaluate the accuracy in diagnosing subependymal gray matter heterotopias in fetuses with spinal dysraphism on fetal MR imaging. This study is a retrospective analysis of 203 fetal MRIs performed at a single institution for spinal dysraphism during a 10-year period. Corresponding obstetric sonography, postnatal imaging, and clinical/operative reports were reviewed. Of the fetal MRIs reviewed, 95 fetuses were included in our analysis; 23.2% (22/95) were suspected of having subependymal gray matter heterotopias on fetal MR imaging prospectively. However, only 50% (11/22) of these cases were confirmed on postnatal brain MR imaging. On postnatal brain MR imaging, 28.4% (27/95) demonstrated imaging findings consistent with subependymal gray matter heterotopia. Only 40.7% (11/27) of these cases were prospectively diagnosed on fetal MR imaging. Fetal MR imaging is limited in its ability to identify subependymal gray matter heterotopias in fetuses with spinal dysraphism. It is believed that this limitation relates to a combination of factors, including artifacts from fetal motion, the very small size of fetal neuroanatomy, differences in imaging techniques, and, possibly, irregularity related to denudation of the ependyma/subependyma in the presence of spinal dysraphism and/or stretching of the germinal matrix in ventriculomegaly. © 2016 by American Journal of Neuroradiology.

  14. GRAY CNVUFAC, Black-Body Radiation View Factors with Self-Shadowing

    International Nuclear Information System (INIS)

    Wong, R.L.

    1991-01-01

    Description of program or function: CNVUFAC, the General Dynamics heat-transfer radiation view program, was adapted for use on the LLNL computer system. The input and output were modified, and a node incrementing logic added for compatibility with TRUMP (NESC 771) thermal analyzer and related codes. The program performs the multiple integration necessary to evaluate the geometric black-body radiation node to node view factors. CNVUFAC uses an elemental area summation scheme to evaluate the multiple integrals. The program permits shadowing and self-shadowing. The basic configuration shapes that can be considered are cylinders, cones, spheres, ellipsoids, flat plates, disks, toroids, and polynomials of revolution. Portions of these shapes can also be considered. Card-image output containing node number and view factor information is generated for input to GRAY, a related code. GRAY performs the matrix manipulations necessary to convert black-body radiation heat-transfer view factors to gray-body view factors as required by thermal analyzer codes. The black-body view factors contain only geometric relationships. GRAY allows the effects of multiple gray-body reflections to be included. The resulting effective gray-body view factors can then be used with the corresponding fourth-power temperature differences to obtain the net radiative heat flux. GRAY accepts a matrix input or the card-image output generated by CNVUFAC. The resulting card-image GRAY output is in a form usable by TRUMP

  15. Effect of glucose level on brain FDG-PET images

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Young; Lee, Yong Ki; Ahn, Sung Min [Dept. of Radiological Science, Gachon University, Seongnam (Korea, Republic of)

    2017-06-15

    In addition to tumors, normal tissues, such as the brain and myocardium can intake {sup 18}F-FDG, and the amount of {sup 18}F-FDG intake by normal tissues can be altered by the surrounding environment. Therefore, a process is necessary during which the contrasts of the tumor and normal tissues can be enhanced. Thus, this study examines the effects of glucose levels on FDG PET images of brain tissues, which features high glucose activity at all times, in small animals. Micro PET scan was performed on fourteen mice after injecting {sup 18}F-FDG. The images were compared in relation to fasting. The findings showed that the mean SUV value w as 0 .84 higher in fasted mice than in non-fasted mice. During observation, the images from non-fasted mice showed high accumulation in organs other than the brain with increased surrounding noise. In addition, compared to the non-fasted mice, the fasted mice showed higher early intake and curve increase. The findings of this study suggest that fasting is important in assessing brain functions in brain PET using {sup 18}F-FDG. Additional studies to investigate whether caffeine levels and other preprocessing items have an impact on the acquired images would contribute to reducing radiation exposure in patients.

  16. Effect of glucose level on brain FDG-PET images

    International Nuclear Information System (INIS)

    Kim, In Young; Lee, Yong Ki; Ahn, Sung Min

    2017-01-01

    In addition to tumors, normal tissues, such as the brain and myocardium can intake 18 F-FDG, and the amount of 18 F-FDG intake by normal tissues can be altered by the surrounding environment. Therefore, a process is necessary during which the contrasts of the tumor and normal tissues can be enhanced. Thus, this study examines the effects of glucose levels on FDG PET images of brain tissues, which features high glucose activity at all times, in small animals. Micro PET scan was performed on fourteen mice after injecting 18 F-FDG. The images were compared in relation to fasting. The findings showed that the mean SUV value w as 0 .84 higher in fasted mice than in non-fasted mice. During observation, the images from non-fasted mice showed high accumulation in organs other than the brain with increased surrounding noise. In addition, compared to the non-fasted mice, the fasted mice showed higher early intake and curve increase. The findings of this study suggest that fasting is important in assessing brain functions in brain PET using 18 F-FDG. Additional studies to investigate whether caffeine levels and other preprocessing items have an impact on the acquired images would contribute to reducing radiation exposure in patients

  17. Image-guided regularization level set evolution for MR image segmentation and bias field correction.

    Science.gov (United States)

    Wang, Lingfeng; Pan, Chunhong

    2014-01-01

    Magnetic resonance (MR) image segmentation is a crucial step in surgical and treatment planning. In this paper, we propose a level-set-based segmentation method for MR images with intensity inhomogeneous problem. To tackle the initialization sensitivity problem, we propose a new image-guided regularization to restrict the level set function. The maximum a posteriori inference is adopted to unify segmentation and bias field correction within a single framework. Under this framework, both the contour prior and the bias field prior are fully used. As a result, the image intensity inhomogeneity can be well solved. Extensive experiments are provided to evaluate the proposed method, showing significant improvements in both segmentation and bias field correction accuracies as compared with other state-of-the-art approaches. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Patient dose with quality image under diagnostic reference levels

    International Nuclear Information System (INIS)

    Akula, Suresh Kumar; Singh, Gurvinder; Chougule, Arun

    2016-01-01

    Need to set Diagnostic Reference Level (DRL) for locations for all diagnostic procedures in local as compared to National. The review of DRL's should compare local with national or referenced averages and a note made of any significant variances to these averages and the justification for it. To survey and asses radiation doses to patient and reduce the redundancy in patient imaging to maintain DRLs

  19. Gray Code for Cayley Permutations

    Directory of Open Access Journals (Sweden)

    J.-L. Baril

    2003-10-01

    Full Text Available A length-n Cayley permutation p of a total ordered set S is a length-n sequence of elements from S, subject to the condition that if an element x appears in p then all elements y < x also appear in p . In this paper, we give a Gray code list for the set of length-n Cayley permutations. Two successive permutations in this list differ at most in two positions.

  20. Interpretations of NMR images

    International Nuclear Information System (INIS)

    Shi, J.Z.; McFarland, W.D.; Chen, S.S.; Sadhu, V.K.

    1986-01-01

    Two color display schemes are generally considered in medical images: pseudo-color and color composite. Psuedo-color technique maps the intensity means of a single monochrome image into a three dimensional color space, the gray level is thus replaced by the assigned color. Such a psuedo-color assignment is somewhat arbitrary but may be advantageous if the monochrome image is composed of simple intensity patterns. A good example of psuedo-color application is in nuclear medicine: The change of gray levels can be simply determined and the isocounts from two regions with different surroundings can be readily recognized. However, the use of psuedo-color in CT or MR imaging is controversial because it does not give additional information and may exaggerate insignificant gray scale differences. The color composite technique maps three parametric image data into a three dimensional color space, and thus three monochrome images are merged to form a single color image. The color composite technique increases the number of ways information can be displayed and provides both quantitative and qualitative data about the object or event represented. This paper describes the application of color composite in NMR images

  1. A comparison of subtracted images from dental subtraction programs

    International Nuclear Information System (INIS)

    Han, Won Jeong

    2002-01-01

    To compare the standard deviation of gray levels on digital subtracted images obtained by different dental subtraction programs. Paired periapical films were taken at the lower premolar and molar areas of the phantoms involving human mandible. The bite registration group used Rinn XCP equipment and bite registration material, based on polyvinyl siloxane, for standardization. The no bite registration group used only Rinn XCP equipment. The periapical film images were digitized at 1200 dpi resolution and 256 gray levels by a flat bed scanner with transparency unit. Dental digital subtraction programs used for this study were Subtractor (Biomedisys Co., Korea) and Emago (Oral Diagnostic Systems, The Netherlands). To measure the similarities between the subtracted images, the standard deviations of the gray levels were obtained using a histogram of subtracted images, which were then analyzed statistically. Subtracted images obtained by using the Emago program without manual selection of corresponding points showed the lowest standard deviation of gray levels (p<0.01). And the standard deviation of gray levels was lower in subtracted images in the group of a bite registration than in the group of no use of bite registration (p<0.01). Digital radiographic subtraction without manual selection of reference points was found to be a convenient and superior method.

  2. A comparative study of image low level feature extraction algorithms

    Directory of Open Access Journals (Sweden)

    M.M. El-gayar

    2013-07-01

    Full Text Available Feature extraction and matching is at the base of many computer vision problems, such as object recognition or structure from motion. Current methods for assessing the performance of popular image matching algorithms are presented and rely on costly descriptors for detection and matching. Specifically, the method assesses the type of images under which each of the algorithms reviewed herein perform to its maximum or highest efficiency. The efficiency is measured in terms of the number of matches founds by the algorithm and the number of type I and type II errors encountered when the algorithm is tested against a specific pair of images. Current comparative studies asses the performance of the algorithms based on the results obtained in different criteria such as speed, sensitivity, occlusion, and others. This study addresses the limitations of the existing comparative tools and delivers a generalized criterion to determine beforehand the level of efficiency expected from a matching algorithm given the type of images evaluated. The algorithms and the respective images used within this work are divided into two groups: feature-based and texture-based. And from this broad classification only three of the most widely used algorithms are assessed: color histogram, FAST (Features from Accelerated Segment Test, SIFT (Scale Invariant Feature Transform, PCA-SIFT (Principal Component Analysis-SIFT, F-SIFT (fast-SIFT and SURF (speeded up robust features. The performance of the Fast-SIFT (F-SIFT feature detection methods are compared for scale changes, rotation, blur, illumination changes and affine transformations. All the experiments use repeatability measurement and the number of correct matches for the evaluation measurements. SIFT presents its stability in most situations although its slow. F-SIFT is the fastest one with good performance as the same as SURF, SIFT, PCA-SIFT show its advantages in rotation and illumination changes.

  3. Recent progress in low-level gamma imaging

    International Nuclear Information System (INIS)

    Mahe, C.; Girones, Ph.; Lamadie, F.; Le Goaller, C.

    2007-01-01

    The CEA's Aladin gamma imaging system has been operated successfully for several years in nuclear plants and during decommissioning projects with additional tools such as gamma spectrometry detectors and dose rate probes. The radiological information supplied by these devices is becoming increasingly useful for establishing robust and optimized decommissioning scenarios. Recent technical improvements allow this gamma imaging system to be operated in low-level applications and with shorter acquisition times suitable for decommissioning projects. The compact portable system can be used in places inaccessible to operators. It is quick and easy to implement, notably for onsite component characterization. Feasibility trials and in situ measurements were recently carried out under low-level conditions, mainly on waste packages and glove boxes for decommissioning projects. This paper describes recent low-level in situ applications. These characterization campaigns mainly concerned gamma emitters with γ energy < 700 keV. In many cases, the localization of hot spots by gamma camera was confirmed by additional measurements such as dose rate mapping and gamma spectrometry measurements. These complementary techniques associated with advanced calculation codes (MCNP, Mercure 6.2, Visiplan and Siren) offer a mobile and compact tool for specific assessment of waste packages and glove boxes. (authors)

  4. Blood oxygenation level dependent (BOLD). Renal imaging. Concepts and applications

    International Nuclear Information System (INIS)

    Nissen, Johanna C.; Haneder, Stefan; Schoenberg, Stefan O.; Michaely, Henrik J.

    2010-01-01

    Many renal diseases as well as several pharmacons cause a change in renal blood flow and/or renal oxygenation. The blood oxygenation level dependent (BOLD) imaging takes advantage of local field inhomogeneities and is based on a T2 * -weighted sequence. BOLD is a non-invasive method allowing an estimation of the renal, particularly the medullary oxygenation, and an indirect measurement of blood flow without administration of contrast agents. Thus, effects of different drugs on the kidney and various renal diseases can be controlled and observed. This work will provide an overview of the studies carried out so far and identify ways how BOLD can be used in clinical studies. (orig.)

  5. Lossy/lossless coding of bi-level images

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren

    1997-01-01

    Summary form only given. We present improvements to a general type of lossless, lossy, and refinement coding of bi-level images (Martins and Forchhammer, 1996). Loss is introduced by flipping pixels. The pixels are coded using arithmetic coding of conditional probabilities obtained using a template...... as is known from JBIG and proposed in JBIG-2 (Martins and Forchhammer). Our new state-of-the-art results are obtained using the more general free tree instead of a template. Also we introduce multiple refinement template coding. The lossy algorithm is analogous to the greedy `rate...

  6. Correlation between white matter damage and gray matter lesions in multiple sclerosis patients

    Directory of Open Access Journals (Sweden)

    Xue-mei Han

    2017-01-01

    Full Text Available We observed the characteristics of white matter fibers and gray matter in multiple sclerosis patients, to identify changes in diffusion tensor imaging fractional anisotropy values following white matter fiber injury. We analyzed the correlation between fractional anisotropy values and changes in whole-brain gray matter volume. The participants included 20 patients with relapsing-remitting multiple sclerosis and 20 healthy volunteers as controls. All subjects underwent head magnetic resonance imaging and diffusion tensor imaging. Our results revealed that fractional anisotropy values decreased and gray matter volumes were reduced in the genu and splenium of corpus callosum, left anterior thalamic radiation, hippocampus, uncinate fasciculus, right corticospinal tract, bilateral cingulate gyri, and inferior longitudinal fasciculus in multiple sclerosis patients. Gray matter volumes were significantly different between the two groups in the right frontal lobe (superior frontal, middle frontal, precentral, and orbital gyri, right parietal lobe (postcentral and inferior parietal gyri, right temporal lobe (caudate nucleus, right occipital lobe (middle occipital gyrus, right insula, right parahippocampal gyrus, and left cingulate gyrus. The voxel sizes of atrophic gray matter positively correlated with fractional anisotropy values in white matter association fibers in the patient group. These findings suggest that white matter fiber bundles are extensively injured in multiple sclerosis patients. The main areas of gray matter atrophy in multiple sclerosis are the frontal lobe, parietal lobe, caudate nucleus, parahippocampal gyrus, and cingulate gyrus. Gray matter atrophy is strongly associated with white matter injury in multiple sclerosis patients, particularly with injury to association fibers.

  7. Gray water recycle: Effect of pretreatment technologies on low pressure reverse osmosis treatment

    Science.gov (United States)

    Gray water can be a valuable source of water when properly treated to reduce the risks associated with chemical and microbial contamination to acceptable levels for the intended reuse application. In this study, the treatment of gray water using low pressure reverse osmosis (RO) filtration after pre...

  8. Assessing the disturbance potential of small unoccupied aircraft systems (UAS on gray seals (Halichoerus grypus at breeding colonies in Nova Scotia, Canada

    Directory of Open Access Journals (Sweden)

    Lauren Arona

    2018-03-01

    Full Text Available The use of small unoccupied aircraft systems (UAS for ecological studies and wildlife population assessments is increasing. These methods can provide significant benefits in terms of costs and reductions in human risk, but little is known if UAS-based approaches cause disturbance of animals during operations. To address this knowledge gap, we conducted a series of UAS flights at gray seal breeding colonies on Hay and Saddle Islands in Nova Scotia, Canada. Using a small fixed-wing UAS, we assessed both immediate and short-term effects of surveys using sequential image analysis and between-flight seal counts in ten, 50 m2 random quadrats at each colony. Counts of adult gray seals and young-of-the-year animals between first and second flights revealed no changes in abundance in quadrats (matched pair t-test p > 0.69 and slopes approaching 1 for linear regression comparisons (r2 > 0.80. Sequential image analysis revealed no changes in orientation or posture of imaged animals. We also assessed the acoustic properties of the small UAS in relation to low ambient noise conditions using sound equivalent level (Leq measurements with a calibrated U-MIK 1 and a 1/3 octave band soundscape approach. The results of Leq measurements indicate that small fixed-wing UAS are quiet, with most energy above 160 Hz, and that levels across 1/3 octave bands do not greatly exceed ambient acoustic measurements in a quiet field during operations at standard survey altitudes. As such, this platform is unlikely to acoustically disturb gray seals at breeding colonies during population surveys. The results of the present study indicate that the effects of small fixed-wing UAS on gray seals at breeding colonies are negligible, and that fixed-wing UAS-based approaches should be considered amongst best practices for assessing gray seal colonies.

  9. MRI Texture Analysis Reveals Deep Gray Nuclei Damage in Amyotrophic Lateral Sclerosis.

    Science.gov (United States)

    de Albuquerque, Milena; Anjos, Lara G V; Maia Tavares de Andrade, Helen; de Oliveira, Márcia S; Castellano, Gabriela; Junqueira Ribeiro de Rezende, Thiago; Nucci, Anamarli; França Junior, Marcondes Cavalcante

    2016-01-01

    Amyotrophic Lateral Sclerosis (ALS) is characterized by extensive corticospinal damage, but extrapyramidal involvement is suggested in pathological studies. Texture analysis (TA) is an image processing technique that evaluates the distribution of gray levels between pixels in a given region of interest (ROI). It provides quantitative data and has been employed in several neurodegenerative disorders. Here, we used TA to investigate possible deep gray nuclei (DGN) abnormalities in a cohort of ALS patients. Thirty-two ALS patients and 32 healthy controls underwent MRI in a 3T scanner. The T1 volumetric sequence was used for DGN segmentation and extraction of 11 texture parameters using the MaZda software. Statistical analyses were performed using the Mann-Whitney non-parametric test, with a significance level set at α = 0.025 (FDR-corrected) for TA. Patients had significantly higher values for the parameter correlation (CO) in both thalami and in the right caudate nucleus compared to healthy controls. Also, the parameter Inverse Difference Moment or Homogeneity (IDM) presented significantly smaller values in the ALS group in both thalami. TA of T1 weighted images revealed DGN alterations in patients with ALS, namely in the thalami and caudate nuclei. Copyright © 2015 by the American Society of Neuroimaging.

  10. Correlation among body height, intelligence, and brain gray matter volume in healthy children.

    Science.gov (United States)

    Taki, Yasuyuki; Hashizume, Hiroshi; Sassa, Yuko; Takeuchi, Hikaru; Asano, Michiko; Asano, Kohei; Kotozaki, Yuka; Nouchi, Rui; Wu, Kai; Fukuda, Hiroshi; Kawashima, Ryuta

    2012-01-16

    A significant positive correlation between height and intelligence has been demonstrated in children. Additionally, intelligence has been associated with the volume of gray matter in the brains of children. Based on these correlations, we analyzed the correlation among height, full-scale intelligence quotient (IQ) and gray matter volume applying voxel-based morphometry using data from the brain magnetic resonance images of 160 healthy children aged 5-18 years of age. As a result, body height was significantly positively correlated with brain gray matter volume. Additionally, the regional gray matter volume of several regions such as the bilateral prefrontal cortices, temporoparietal region, and cerebellum was significantly positively correlated with body height and that the gray matter volume of several of these regions was also significantly positively correlated with full-scale intelligence quotient (IQ) scores after adjusting for age, sex, and socioeconomic status. Our results demonstrate that gray and white matter volume may mediate the correlation between body height and intelligence in healthy children. Additionally, the correlations among gray and white matter volume, height, and intelligence may be at least partially explained by the effect of insulin-like growth factor-1 and growth hormones. Given the importance of the effect of environmental factors, especially nutrition, on height, IQ, and gray matter volume, the present results stress the importance of nutrition during childhood for the healthy maturation of body and brain. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Differential regional gray matter volumes in patients with on-line game addiction and professional gamers

    Science.gov (United States)

    Han, Doug Hyun; Lyoo, In Kyoon; Renshaw, Perry F.

    2015-01-01

    Patients with on-line game addiction (POGA) and professional video game players play video games for extended periods of time, but experience very different consequences for their on-line game play. Brain regions consisting of anterior cingulate, thalamus and occpito-temporal areas may increase the likelihood of becoming a pro-gamer or POGA. Twenty POGA, seventeen pro-gamers, and eighteen healthy comparison subjects (HC) were recruited. All magnetic resonance imaging (MRI) was performed on a 1.5 Tesla Espree MRI scanner (SIEMENS, Erlangen, Germany). Voxel-wise comparisons of gray matter volume were performed between the groups using the two-sample t-test with statistical parametric mapping (SPM5). Compared to HC, the POGA group showed increased impulsiveness and perseverative errors, and volume in left thalamus gray matter, but decreased gray matter volume in both inferior temporal gyri, right middle occipital gyrus, and left inferior occipital gyrus, compared with HC. Pro-gamers showed increased gray matter volume in left cingulate gyrus, but decreased gray matter volume in left middle occipital gyrus and right inferior temporal gyrus compared with HC. Additionally, the pro-gamer group showed increased gray matter volume in left cingulate gyrus and decreased left thalamus gray matter volume compared with the POGA group. The current study suggests that increased gray matter volumes of the left cingulate gyrus in pro-gamers and of the left thalamus in POGA may contribute to the different clinical characteristics of pro-gamers and POGA. PMID:22277302

  12. Influence of the gray gases number in the weighted sum of gray gases model on the radiative heat exchange calculation inside pulverized coal-fired furnaces

    Directory of Open Access Journals (Sweden)

    Crnomarković Nenad Đ.

    2016-01-01

    Full Text Available The influence of the number of gray gases in the weighted sum in the gray gases model on the calculation of the radiative heat transfer is discussed in the paper. A computer code which solved the set of equations of the mathematical model describing the reactive two-phase turbulent flow with radiative heat exchange and with thermal equilibrium between phases inside the pulverized coal-fired furnace was used. Gas-phase radiative properties were determined by the simple gray gas model and two combinations of the weighted sum of the gray gases models: one gray gas plus a clear gas and two gray gases plus a clear gas. Investigation was carried out for two values of the total extinction coefficient of the dispersed phase, for the clean furnace walls and furnace walls covered by an ash layer deposit, and for three levels of the approximation accuracy of the weighting coefficients. The influence of the number of gray gases was analyzed through the relative differences of the wall fluxes, wall temperatures, medium temperatures, and heat transfer rate through all furnace walls. The investigation showed that there were conditions of the numerical investigations for which the relative differences of the variables describing the radiative heat exchange decrease with the increase in the number of gray gases. The results of this investigation show that if the weighted sum of the gray gases model is used, the complexity of the computer code and calculation time can be reduced by optimizing the number of gray gases. [Projekat Ministarstva nauke Republike Srbije, br. TR-33018: Increase in energy and ecology efficiency of processes in pulverized coal-fired furnace and optimization of utility steam boiler air preheater by using in-house developed software tools

  13. Clinical and Morphological Aspects of Gray Matter Heterotopia Type Developmental Malformations

    International Nuclear Information System (INIS)

    Zając-Mnich, Monika; Kostkiewicz, Agnieszka; Guz, Wiesław; Dziurzyńska-Białek, Ewa; Solińska, Anna; Stopa, Joanna; Kucharska-Miąsik, Iwona

    2014-01-01

    Gray matter heterotopia (GMH) is a malformation of the central nervous system characterized by interruption of normal neuroblasts migration between the 7 th and 16 th week of fetal development. The aim of the study was the analysis of clinical symptoms, prevalence rate and the most common concurrent central nervous system (CNS) developmental disorders as well as assessment of characteristic morphological changes of gray matter heterotopia in children hospitalized in our institution between the year 2001 and 2012. We performed a retrospective analysis of patients’ data who were hospitalized in our institution between the year 2001 and 2012. We assessed clinical data and imaging exams in children diagnosed with gray matter heterotopia confirmed in MRI (magnetic resonance imaging). GMH occurred in 26 children hospitalized in our institution between the year 2001 and 2012. Among children with gray matter heterotopia most common clinical symptoms were: epilepsy, intellectual disability and hemiparesis. The commonest location of heterotopic gray matter were fronto-parietal areas of brain parenchyma, mostly subependymal region. Gray matter heterotopia occurred with other developmental disorders of the central nervous system rather than solely and in most cases it was bilateral. Schizencephaly and abnormalities of the corpus callosum were the most often developmental disorders accompanying GMH. 1. Subependymal gray matter heterotopia was more common than subcortical GMH. Subependymal GMH showed tendency to localize in the region of the bodies of the lateral ventricles. The least common was laminar GMH. 2. Gray matter heterotopia occurred more often with other developmental disorders of the central nervous system rather than solely. The most frequent concurrent disorders of the central nervous system were: schizencephaly, developmental abnormalities of the corpus callosum, arachnoid cyst, abnormalities of the septum pellucidum and the fornix. 3. GMH foci were more often

  14. Examining the effect of psychopathic traits on gray matter volume in a community substance abuse sample.

    Science.gov (United States)

    Cope, Lora M; Shane, Matthew S; Segall, Judith M; Nyalakanti, Prashanth K; Stevens, Michael C; Pearlson, Godfrey D; Calhoun, Vince D; Kiehl, Kent A

    2012-11-30

    Psychopathy is believed to be associated with brain abnormalities in both paralimbic (i.e., orbitofrontal cortex, insula, temporal pole, parahippocampal gyrus, posterior cingulate) and limbic (i.e., amygdala, hippocampus, anterior cingulate) regions. Recent structural imaging studies in both community and prison samples are beginning to support this view. Sixty-six participants, recruited from community corrections centers, were administered the Hare psychopathy checklist-revised (PCL-R), and underwent magnetic resonance imaging (MRI). Voxel-based morphometry was used to test the hypothesis that psychopathic traits would be associated with gray matter reductions in limbic and paralimbic regions. Effects of lifetime drug and alcohol use on gray matter volume were covaried. Psychopathic traits were negatively associated with gray matter volumes in right insula and right hippocampus. Additionally, psychopathic traits were positively associated with gray matter volumes in bilateral orbital frontal cortex and right anterior cingulate. Exploratory regression analyses indicated that gray matter volumes within right hippocampus and left orbital frontal cortex combined to explain 21.8% of the variance in psychopathy scores. These results support the notion that psychopathic traits are associated with abnormal limbic and paralimbic gray matter volume. Furthermore, gray matter increases in areas shown to be functionally impaired suggest that the structure-function relationship may be more nuanced than previously thought. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  15. Multiparameter fluorescence imaging for quantification of TH-1 and TH-2 cytokines at the single-cell level

    Science.gov (United States)

    Fekkar, Hakim; Benbernou, N.; Esnault, S.; Shin, H. C.; Guenounou, Moncef

    1998-04-01

    Immune responses are strongly influenced by the cytokines following antigenic stimulation. Distinct cytokine-producing T cell subsets are well known to play a major role in immune responses and to be differentially regulated during immunological disorders, although the characterization and quantification of the TH-1/TH-2 cytokine pattern in T cells remained not clearly defined. Expression of cytokines by T lymphocytes is a highly balanced process, involving stimulatory and inhibitory intracellular signaling pathways. The aim of this study was (1) to quantify the cytokine expression in T cells at the single cell level using optical imaging, (2) and to analyze the influence of cyclic AMP- dependent signal transduction pathway in the balance between the TH-1 and TH-2 cytokine profile. We attempted to study several cytokines (IL-2, IFN-(gamma) , IL-4, IL-10 and IL-13) in peripheral blood mononuclear cells. Cells were prestimulated in vitro using phytohemagglutinin and phorbol ester for 36h, and then further cultured for 8h in the presence of monensin. Cells were permeabilized and then simple-, double- or triple-labeled with the corresponding specific fluorescent monoclonal antibodies. The cell phenotype was also determined by analyzing the expression of each of CD4, CD8, CD45RO and CD45RA with the cytokine expression. Conventional images of cells were recorded with a Peltier- cooled CCD camera (B/W C5985, Hamamatsu photonics) through an inverted microscope equipped with epi-fluorescence (Diaphot 300, Nikon). Images were digitalized using an acquisition video interface (Oculus TCX Coreco) in 762 by 570 pixels coded in 8 bits (256 gray levels), and analyzed thereafter in an IBM PC computer based on an intel pentium processor with an adequate software (Visilog 4, Noesis). The first image processing step is the extraction of cell areas using an edge detection and a binary thresholding method. In order to reduce the background noise of fluorescence, we performed an opening

  16. Changes in lactate dehydrogenase are associated with central gray matter lesions in newborns with hypoxic-ischemic encephalopathy.

    Science.gov (United States)

    Yum, Sook Kyung; Moon, Cheong-Jun; Youn, Young-Ah; Sung, In Kyung

    2017-05-01

    Biomarkers may predict neurological prognosis in infants with hypoxic-ischemic encephalopathy (HIE). We evaluated the relationship between serum lactate dehydrogenase (LDH) and brain magnetic resonance imaging (MRI), which predicts neurodevelopmental outcomes, in order to assess whether LDH levels are similarly predictive. Medical records were reviewed for infants with HIE and LDH levels were assessed on the first (LDH 1 ) and third (LDH 3 ) days following birth. Receiver operating characteristic curves were obtained in relation to central gray matter hypoxic-ischemic lesions. Of 92 patients, 52 (56.5%) had hypoxic-ischemic lesions on brain MRI, and 21 of these infants (40.4%) had central gray matter lesions. LDH 1 and LDH 3 did not differ; however, the percentage change (ΔLDH%) was significantly higher in infants with central gray matter lesions (36.9% versus 6.6%, p = 0.006). With cutoffs of 187 (IU/L, ΔLDH) and 19.4 (%, ΔLDH%), the sensitivity, specificity, positive predictive value and negative predictive value were 71.4, 69.0, 40.5 and 89.1%, respectively. The relative risk was 5.57 (p = 0.001). Changes in serum LDH may be a useful biomarker for predicting future neurodevelopmental prognosis in infants with HIE.

  17. Advances in low-level color image processing

    CERN Document Server

    Smolka, Bogdan

    2014-01-01

    Color perception plays an important role in object recognition and scene understanding both for humans and intelligent vision systems. Recent advances in digital color imaging and computer hardware technology have led to an explosion in the use of color images in a variety of applications including medical imaging, content-based image retrieval, biometrics, watermarking, digital inpainting, remote sensing, visual quality inspection, among many others. As a result, automated processing and analysis of color images has become an active area of research, to which the large number of publications of the past two decades bears witness. The multivariate nature of color image data presents new challenges for researchers and practitioners as the numerous methods developed for single channel images are often not directly applicable to multichannel  ones. The goal of this volume is to summarize the state-of-the-art in the early stages of the color image processing pipeline.

  18. "Mr. Database" : Jim Gray and the History of Database Technologies.

    Science.gov (United States)

    Hanwahr, Nils C

    2017-12-01

    Although the widespread use of the term "Big Data" is comparatively recent, it invokes a phenomenon in the developments of database technology with distinct historical contexts. The database engineer Jim Gray, known as "Mr. Database" in Silicon Valley before his disappearance at sea in 2007, was involved in many of the crucial developments since the 1970s that constitute the foundation of exceedingly large and distributed databases. Jim Gray was involved in the development of relational database systems based on the concepts of Edgar F. Codd at IBM in the 1970s before he went on to develop principles of Transaction Processing that enable the parallel and highly distributed performance of databases today. He was also involved in creating forums for discourse between academia and industry, which influenced industry performance standards as well as database research agendas. As a co-founder of the San Francisco branch of Microsoft Research, Gray increasingly turned toward scientific applications of database technologies, e. g. leading the TerraServer project, an online database of satellite images. Inspired by Vannevar Bush's idea of the memex, Gray laid out his vision of a Personal Memex as well as a World Memex, eventually postulating a new era of data-based scientific discovery termed "Fourth Paradigm Science". This article gives an overview of Gray's contributions to the development of database technology as well as his research agendas and shows that central notions of Big Data have been occupying database engineers for much longer than the actual term has been in use.

  19. The Effect of Illumination on Gray Color

    Science.gov (United States)

    Da Pos, Osvaldo; Baratella, Linda; Sperandio, Gabriele

    2010-01-01

    The present study explored the perceptual process of integration of luminance information in the production of the gray color of an object placed in an environment viewed from a window. The mean luminance of the object was varied for each mean luminance of the environment. Participants matched the gray color of the object with that of Munsell…

  20. Neuroinflammatory component of gray matter pathology in multiple sclerosis.

    Science.gov (United States)

    Herranz, Elena; Giannì, Costanza; Louapre, Céline; Treaba, Constantina A; Govindarajan, Sindhuja T; Ouellette, Russell; Loggia, Marco L; Sloane, Jacob A; Madigan, Nancy; Izquierdo-Garcia, David; Ward, Noreen; Mangeat, Gabriel; Granberg, Tobias; Klawiter, Eric C; Catana, Ciprian; Hooker, Jacob M; Taylor, Norman; Ionete, Carolina; Kinkel, Revere P; Mainero, Caterina

    2016-11-01

    In multiple sclerosis (MS), using simultaneous magnetic resonance-positron emission tomography (MR-PET) imaging with 11 C-PBR28, we quantified expression of the 18kDa translocator protein (TSPO), a marker of activated microglia/macrophages, in cortex, cortical lesions, deep gray matter (GM), white matter (WM) lesions, and normal-appearing WM (NAWM) to investigate the in vivo pathological and clinical relevance of neuroinflammation. Fifteen secondary-progressive MS (SPMS) patients, 12 relapsing-remitting MS (RRMS) patients, and 14 matched healthy controls underwent 11 C-PBR28 MR-PET. MS subjects underwent 7T T2*-weighted imaging for cortical lesion segmentation, and neurological and cognitive evaluation. 11 C-PBR28 binding was measured using normalized 60- to 90-minute standardized uptake values and volume of distribution ratios. Relative to controls, MS subjects exhibited abnormally high 11 C-PBR28 binding across the brain, the greatest increases being in cortex and cortical lesions, thalamus, hippocampus, and NAWM. MS WM lesions showed relatively modest TSPO increases. With the exception of cortical lesions, where TSPO expression was similar, 11 C-PBR28 uptake across the brain was greater in SPMS than in RRMS. In MS, increased 11 C-PBR28 binding in cortex, deep GM, and NAWM correlated with neurological disability and impaired cognitive performance; cortical thinning correlated with increased thalamic TSPO levels. In MS, neuroinflammation is present in the cortex, cortical lesions, deep GM, and NAWM, is closely linked to poor clinical outcome, and is at least partly linked to neurodegeneration. Distinct inflammatory-mediated factors may underlie accumulation of cortical and WM lesions. Quantification of TSPO levels in MS could prove to be a sensitive tool for evaluating in vivo the inflammatory component of GM pathology, particularly in cortical lesions. Ann Neurol 2016;80:776-790. © 2016 American Neurological Association.

  1. Interaction between High-Level and Low-Level Image Analysis for Semantic Video Object Extraction

    Directory of Open Access Journals (Sweden)

    Andrea Cavallaro

    2004-06-01

    Full Text Available The task of extracting a semantic video object is split into two subproblems, namely, object segmentation and region segmentation. Object segmentation relies on a priori assumptions, whereas region segmentation is data-driven and can be solved in an automatic manner. These two subproblems are not mutually independent, and they can benefit from interactions with each other. In this paper, a framework for such interaction is formulated. This representation scheme based on region segmentation and semantic segmentation is compatible with the view that image analysis and scene understanding problems can be decomposed into low-level and high-level tasks. Low-level tasks pertain to region-oriented processing, whereas the high-level tasks are closely related to object-level processing. This approach emulates the human visual system: what one “sees” in a scene depends on the scene itself (region segmentation as well as on the cognitive task (semantic segmentation at hand. The higher-level segmentation results in a partition corresponding to semantic video objects. Semantic video objects do not usually have invariant physical properties and the definition depends on the application. Hence, the definition incorporates complex domain-specific knowledge and is not easy to generalize. For the specific implementation used in this paper, motion is used as a clue to semantic information. In this framework, an automatic algorithm is presented for computing the semantic partition based on color change detection. The change detection strategy is designed to be immune to the sensor noise and local illumination variations. The lower-level segmentation identifies the partition corresponding to perceptually uniform regions. These regions are derived by clustering in an N-dimensional feature space, composed of static as well as dynamic image attributes. We propose an interaction mechanism between the semantic and the region partitions which allows to

  2. Cerebral Metabolic Rate of Oxygen (CMRO2 ) Mapping by Combining Quantitative Susceptibility Mapping (QSM) and Quantitative Blood Oxygenation Level-Dependent Imaging (qBOLD).

    Science.gov (United States)

    Cho, Junghun; Kee, Youngwook; Spincemaille, Pascal; Nguyen, Thanh D; Zhang, Jingwei; Gupta, Ajay; Zhang, Shun; Wang, Yi

    2018-03-07

    To map the cerebral metabolic rate of oxygen (CMRO 2 ) by estimating the oxygen extraction fraction (OEF) from gradient echo imaging (GRE) using phase and magnitude of the GRE data. 3D multi-echo gradient echo imaging and perfusion imaging with arterial spin labeling were performed in 11 healthy subjects. CMRO 2 and OEF maps were reconstructed by joint quantitative susceptibility mapping (QSM) to process GRE phases and quantitative blood oxygen level-dependent (qBOLD) modeling to process GRE magnitudes. Comparisons with QSM and qBOLD alone were performed using ROI analysis, paired t-tests, and Bland-Altman plot. The average CMRO 2 value in cortical gray matter across subjects were 140.4 ± 14.9, 134.1 ± 12.5, and 184.6 ± 17.9 μmol/100 g/min, with corresponding OEFs of 30.9 ± 3.4%, 30.0 ± 1.8%, and 40.9 ± 2.4% for methods based on QSM, qBOLD, and QSM+qBOLD, respectively. QSM+qBOLD provided the highest CMRO 2 contrast between gray and white matter, more uniform OEF than QSM, and less noisy OEF than qBOLD. Quantitative CMRO 2 mapping that fits the entire complex GRE data is feasible by combining QSM analysis of phase and qBOLD analysis of magnitude. © 2018 International Society for Magnetic Resonance in Medicine.

  3. Low level image processing techniques using the pipeline image processing engine in the flight telerobotic servicer

    Science.gov (United States)

    Nashman, Marilyn; Chaconas, Karen J.

    1988-01-01

    The sensory processing system for the NASA/NBS Standard Reference Model (NASREM) for telerobotic control is described. This control system architecture was adopted by NASA of the Flight Telerobotic Servicer. The control system is hierarchically designed and consists of three parallel systems: task decomposition, world modeling, and sensory processing. The Sensory Processing System is examined, and in particular the image processing hardware and software used to extract features at low levels of sensory processing for tasks representative of those envisioned for the Space Station such as assembly and maintenance are described.

  4. Brain gray matter structural network in myotonic dystrophy type 1.

    Directory of Open Access Journals (Sweden)

    Atsuhiko Sugiyama

    Full Text Available This study aimed to investigate abnormalities in structural covariance network constructed from gray matter volume in myotonic dystrophy type 1 (DM1 patients by using graph theoretical analysis for further clarification of the underlying mechanisms of central nervous system involvement. Twenty-eight DM1 patients (4 childhood onset, 10 juvenile onset, 14 adult onset, excluding three cases from 31 consecutive patients who underwent magnetic resonance imaging in a certain period, and 28 age- and sex- matched healthy control subjects were included in this study. The normalized gray matter images of both groups were subjected to voxel based morphometry (VBM and Graph Analysis Toolbox for graph theoretical analysis. VBM revealed extensive gray matter atrophy in DM1 patients, including cortical and subcortical structures. On graph theoretical analysis, there were no significant differences between DM1 and control groups in terms of the global measures of connectivity. Betweenness centrality was increased in several regions including the left fusiform gyrus, whereas it was decreased in the right striatum. The absence of significant differences between the groups in global network measurements on graph theoretical analysis is consistent with the fact that the general cognitive function is preserved in DM1 patients. In DM1 patients, increased connectivity in the left fusiform gyrus and decreased connectivity in the right striatum might be associated with impairment in face perception and theory of mind, and schizotypal-paranoid personality traits, respectively.

  5. [Comparison of film-screen combinations in contrast-detail diagram and with interactive image analysis. 3: Trimodal histograms of gray scale distribution in bar groups of lead pattern images].

    Science.gov (United States)

    Hagemann, G; Eichbaum, G; Stamm, G

    1998-05-01

    The following four screen film combinations were compared: a) a combination of anticrossover film and UV-light emitting screens, b) a combination of blue-light emitting screens and film and c) two conventional green fluorescing screen film combinations. Radiographs of a specially designed plexiglass phantom (0.2 x 0.2 x 0.12 m3) with bar patterns of lead and plaster and of air, respectively were obtained using the following parameters: 12 pulse generator, 0.6 mm focus size, 4.7 mm aluminum prefilter, a grid with 40 lines/cm (12:1) and a focus-detector distance of 1.15 m. Image analysis was performed using an Ibas system and a Zeiss Kontron computer. Display conditions were the following: display distance 0.12 m, a vario film objective 35/70 (Zeiss), a video camera tube with a PbO photocathode, 625 lines (Siemens Heimann), an Ibas image matrix of 512 x 512 pixels with a spatial resolution of ca. 7 cycles/mm, the projected matrix area was 5000 micron 2. Maxima in the histograms of a grouped bar pattern were estimated as mean values from the bar and gap regions ("mean value method"). They were used to calculate signal contrast, standard deviations of the means and scatter fraction. Comparing the histograms with respect to spatial resolution and kV setting a clear advantage of the UVR system becomes obvious. The quantitative analysis yielded a maximum spatial resolution of approx. 3 cycles/mm for the UVR system at 60 kV which decreased to half of this value at 117 kV caused by the increasing influence of scattered radiation. A ranking of screen-film systems with respect to image quality and dose requirement is presented. For its evaluation an interactive image analysis using the mean value method was found to be superior to signal/noise ratio measurements and visual analysis in respect to diagnostic relevance and saving of time.

  6. MASTICATORY MUSCLE MYOSITIS IN A GRAY WOLF (CANIS LUPUS).

    Science.gov (United States)

    Kent, Marc; Glass, Eric N; Castro, Fernando A; Miller, Andrew D; de Lahunta, Alexander

    2017-03-01

    A 10-yr-old male, neutered gray wolf ( Canis lupus ) was presented for atrophy of the temporalis and masseter muscles. Clinical signs and magnetic resonance imaging were consistent with a myopathy. Positive serology for antibody titers directed against Type 2M myofibers, and the observation of a mixed mononuclear inflammatory cell infiltrate along with eosinophils and neutrophils within the temporalis muscle, were diagnostic for masticatory muscle myositis. Importantly, protozoal myositis was excluded based on other clinicopathologic data. The case highlights the potential for immune-mediated polymyositis in canids other than the domesticated dog ( Canis lupus familaris). Additionally, awareness of a diet in which raw meat is used should prompt a thorough investigation for an underlying infectious myositis in the gray wolf.

  7. Second order statistical analysis of US image texture

    International Nuclear Information System (INIS)

    Tanzi, F.; Novario, R.

    1999-01-01

    The study reports the sonographic image texture of the neonatal heart in different stages of development by calculating numerical parameters extracted from the gray scale co-occurrence matrix. To show pixel values differences and enhance texture structure, images were equalized and then the gray level range was reduced to 16 to allow sufficiently high occupancy frequency of the co-occurrence matrix. Differences are so little significant that they may be due to different factors affecting image texture and the variability introduced by manual ROI positioning; therefore no definitive conclusions can be drawn as to considering this kind of analysis capable of discriminating different stages of myocardial development [it

  8. An Assessment of Gray Whale Movements in Acoustically Changing Nearshore Environments

    National Research Council Canada - National Science Library

    Mate, Bruce

    1999-01-01

    This grant helped fluid six field seasons over four years. The initial objective was to investigate the movements of gray whales in environments with varying levels of development and acoustic stimuli...

  9. Image processing with a cellular nonlinear network

    International Nuclear Information System (INIS)

    Morfu, S.

    2005-01-01

    A cellular nonlinear network (CNN) based on uncoupled nonlinear oscillators is proposed for image processing purposes. It is shown theoretically and numerically that the contrast of an image loaded at the nodes of the CNN is strongly enhanced, even if this one is initially weak. An image inversion can be also obtained without reconfiguration of the network whereas a gray levels extraction can be performed with an additional threshold filtering. Lastly, an electronic implementation of this CNN is presented

  10. GrayQbTM Single-Faced Version 2 (SF2) Hanford Plutonium Reclamation Facility (PRF) deployment report

    Energy Technology Data Exchange (ETDEWEB)

    Plummer, J. R. [Savannah River Site (SRS), Aiken, SC (United States); Immel, D. M. [Savannah River Site (SRS), Aiken, SC (United States); Serrato, M. G. [Savannah River Site (SRS), Aiken, SC (United States); Dalmaso, M. J. [Savannah River Site (SRS), Aiken, SC (United States); Shull, D. J. [Savannah River Site (SRS), Aiken, SC (United States)

    2015-11-18

    The Savannah River National Laboratory (SRNL) in partnership with CH2M Plateau Remediation Company (CHPRC) deployed the GrayQbTM SF2 radiation imaging device at the Hanford Plutonium Reclamation Facility (PRF) to assist in the radiological characterization of the canyon. The deployment goal was to locate radiological contamination hot spots in the PRF canyon, where pencil tanks were removed and decontamination/debris removal operations are on-going, to support the CHPRC facility decontamination and decommissioning (D&D) effort. The PRF canyon D&D effort supports completion of the CHPRC Plutonium Finishing Plant Decommissioning Project. The GrayQbTM SF2 (Single Faced Version 2) is a non-destructive examination device developed by SRNL to generate radiation contour maps showing source locations and relative radiological levels present in the area under examination. The Hanford PRF GrayQbTM Deployment was sponsored by CH2M Plateau Remediation Company (CHPRC) through the DOE Richland Operations Office, Inter-Entity Work Order (IEWO), DOE-RL IEWO- M0SR900210.

  11. Indium-111 labeled leukocyte images demonstrating a lung abscess with prominent fluid level

    International Nuclear Information System (INIS)

    Massie, J.D.; Winer-Muram, H.

    1986-01-01

    In-111 labeled leukocyte images show an abscess cavity with a fluid level on 24-hour upright images. Fluid levels, frequently seen on radiographs, are uncommon on nuclear images. This finding demonstrates rapid migration of labeled leukocytes into purulent abscess fluid

  12. The effect of base image window level selection on the dimensional measurement accuracy of resultant three-dimensional image displays

    International Nuclear Information System (INIS)

    Kurmis, A.P.; Hearn, T.C.; Reynolds, K.J.

    2003-01-01

    Purpose: The aim of this study was to determine the effect of base image window level selection on direct linear measurement of knee structures displayed using new magnetic resonance (MR)-based three-dimensional reconstructed computer imaging techniques. Methods: A prospective comparative study was performed using a series of three-dimensional knee images, generated from conventional MR imaging (MRI) sections. Thirty distinct anatomical structural features were identified within the image series of which repeated measurements were compared at 10 different window grey scale levels. Results: Statistical analysis demonstrated an excellent raw correlation between measurements and suggested no significant difference between measurements made at each of the 10 window level settings (P>0.05). Conclusions: The findings of this study suggest that unlike conventional MR or CT applications, grey scale window level selection at the time of imaging does not significantly affect the visual quality of resultant three-dimensional reconstructed images and hence the accuracy of subsequent direct linear measurement. The diagnostic potential of clinical progression from routine two-dimensional to advanced three-dimensional reconstructed imaging techniques may therefore be less likely to be degraded by inappropriate MR technician image windowing during the capturing of image series

  13. Eileen Gray: a child of Japonism?

    OpenAIRE

    Starr, Ruth

    2008-01-01

    Exhibited at the Glucksman Memorial Symposium on June 12th 2008 My interest is in Gray's lacquer work and the influences on that work in the context of nineteenth-century fashion of Japonisme. Gray (1878-1976) had an appreciation of the Japanese characteristics of lacquer - perhaps absorbed from private and public Irish collections of Japanese art. Gray also had a twenty-year working collaboration with Seizo Sugawara (1884-1937) from Jahoji, Japan - a town famous for its lacquer work. Suga...

  14. Different regional gray matter loss in recent onset PTSD and non PTSD after a single prolonged trauma exposure.

    Directory of Open Access Journals (Sweden)

    Yunchun Chen

    Full Text Available OBJECTIVE: Gray matter loss in the limbic structures was found in recent onset post traumatic stress disorder (PTSD patients. In the present study, we measured regional gray matter volume in trauma survivors to verify the hypothesis that stress may cause different regional gray matter loss in trauma survivors with and without recent onset PTSD. METHOD: High resolution T1-weighted magnetic resonance imaging (MRI were obtained from coal mine flood disaster survivors with (n = 10 and without (n = 10 recent onset PTSD and 20 no trauma exposed normal controls. The voxel-based morphometry (VBM method was used to measure the regional gray matter volume in three groups, the correlations of PTSD symptom severities with the gray matter volume in trauma survivors were also analyzed by multiple regression. RESULTS: Compared with normal controls, recent onset PTSD patients had smaller gray matter volume in left dorsal anterior cingulate cortex (ACC, and non PTSD subjects had smaller gray matter volume in the right pulvinar and left pallidum. The gray matter volume of the trauma survivors correlated negatively with CAPS scores in the right frontal lobe, left anterior and middle cingulate cortex, bilateral cuneus cortex, right middle occipital lobe, while in the recent onset PTSD, the gray matter volume correlated negatively with CAPS scores in bilateral superior medial frontal lobe and right ACC. CONCLUSION: The present study identified gray matter loss in different regions in recent onset PTSD and non PTSD after a single prolonged trauma exposure. The gray matter volume of left dorsal ACC associated with the development of PTSD, while the gray matter volume of right pulvinar and left pallidum associated with the response to the severe stress. The atrophy of the frontal and limbic cortices predicts the symptom severities of the PTSD.

  15. AUTOMATIC MULTILEVEL IMAGE SEGMENTATION BASED ON FUZZY REASONING

    Directory of Open Access Journals (Sweden)

    Liang Tang

    2011-05-01

    Full Text Available An automatic multilevel image segmentation method based on sup-star fuzzy reasoning (SSFR is presented. Using the well-known sup-star fuzzy reasoning technique, the proposed algorithm combines the global statistical information implied in the histogram with the local information represented by the fuzzy sets of gray-levels, and aggregates all the gray-levels into several classes characterized by the local maximum values of the histogram. The presented method has the merits of determining the number of the segmentation classes automatically, and avoiding to calculating thresholds of segmentation. Emulating and real image segmentation experiments demonstrate that the SSFR is effective.

  16. Relationship between Hounsfield Unit in CT Scan and Gray Scale in CBCT

    Directory of Open Access Journals (Sweden)

    Tahmineh Razi

    2014-06-01

    Full Text Available Background and aims. Cone-beam computed tomography (CBCT is an imaging system which has many advantages over computed tomography (CT. In CT scan, Hounsfield Unit (HU is proportional to the degree of x-ray attenuation by the tissue. In CBCT, the degree of x-ray attenuation is shown by gray scale (voxel value. The aim of the present study was to investigate the relationship between gray scale in CBCT and Hounsfield Unit (HU in CT scan. Materials and methods. In this descriptive study, the head of a sheep was scanned with 3 CBCT and one medical CT scanner. Gray scales and HUs were detected on images. Reconstructed data were analyzed to investigate relationship between CBCT gray scales and HUs. Results. A strong correlation between gray scales of CBCT and HUs of CT scan was determined. Conclusion. Considering the fact that gray scale in CBCT is the criteria in measurement of bone density before implant treatments, it is recommended because of the lower dose and cost compared to CT scan.

  17. Occipital Lobe Gray Matter Volume in Male Patients with Chronic Schizophrenia: A Quantitative MRI Study

    Science.gov (United States)

    Onitsuka, Toshiaki; McCarley, Robert W.; Kuroki, Noriomi; Dickey, Chandlee C.; Kubicki, Marek; Demeo, Susan S.; Frumin, Melissa; Kikinis, Ron; Jolesz, Ferenc A.; Shenton, Martha E.

    2008-01-01

    Schizophrenia is characterized by deficits in cognition as well as visual perception. There have, however, been few magnetic resonance imaging (MRI) studies of the occipital lobe as an anatomically defined region of interest in schizophrenia. To examine whether or not patients with chronic schizophrenia show occipital lobe volume abnormalities, we measured gray matter volumes for both the primary visual area (PVA) and the visual association areas (VAA) using MRI based neuroanatomical landmarks and three-dimensional information. PVA and VAA gray matter volumes were measured using high-spatial resolution MRI in 25 male patients diagnosed with chronic schizophrenia and in 28 male normal controls. Chronic schizophrenia patients showed reduced bilateral VAA gray matter volume (11%), compared with normal controls, whereas patients showed no group difference in PVA gray matter volume. These results suggest that reduced bilateral VAA may be a neurobiological substrate of some of the deficits observed in early visual processing in schizophrenia. PMID:17350226

  18. Food Image Recognition via Superpixel Based Low-Level and Mid-Level Distance Coding for Smart Home Applications

    Directory of Open Access Journals (Sweden)

    Jiannan Zheng

    2017-05-01

    Full Text Available Food image recognition is a key enabler for many smart home applications such as smart kitchen and smart personal nutrition log. In order to improve living experience and life quality, smart home systems collect valuable insights of users’ preferences, nutrition intake and health conditions via accurate and robust food image recognition. In addition, efficiency is also a major concern since many smart home applications are deployed on mobile devices where high-end GPUs are not available. In this paper, we investigate compact and efficient food image recognition methods, namely low-level and mid-level approaches. Considering the real application scenario where only limited and noisy data are available, we first proposed a superpixel based Linear Distance Coding (LDC framework where distinctive low-level food image features are extracted to improve performance. On a challenging small food image dataset where only 12 training images are available per category, our framework has shown superior performance in both accuracy and robustness. In addition, to better model deformable food part distribution, we extend LDC’s feature-to-class distance idea and propose a mid-level superpixel food parts-to-class distance mining framework. The proposed framework show superior performance on a benchmark food image datasets compared to other low-level and mid-level approaches in the literature.

  19. Level set segmentation of medical images based on local region statistics and maximum a posteriori probability.

    Science.gov (United States)

    Cui, Wenchao; Wang, Yi; Lei, Tao; Fan, Yangyu; Feng, Yan

    2013-01-01

    This paper presents a variational level set method for simultaneous segmentation and bias field estimation of medical images with intensity inhomogeneity. In our model, the statistics of image intensities belonging to each different tissue in local regions are characterized by Gaussian distributions with different means and variances. According to maximum a posteriori probability (MAP) and Bayes' rule, we first derive a local objective function for image intensities in a neighborhood around each pixel. Then this local objective function is integrated with respect to the neighborhood center over the entire image domain to give a global criterion. In level set framework, this global criterion defines an energy in terms of the level set functions that represent a partition of the image domain and a bias field that accounts for the intensity inhomogeneity of the image. Therefore, image segmentation and bias field estimation are simultaneously achieved via a level set evolution process. Experimental results for synthetic and real images show desirable performances of our method.

  20. Optimized VBM in patients with Alzheimer's disease: gray matter loss and its correlation with cognitive function

    International Nuclear Information System (INIS)

    Choi, Seon Hyeong; Moon, Won Jin; Chung, Eun Chul; Lee, Min Hee; Roh, Hong Gee; Park, Kwang Bo; Na, Duck Ryul

    2005-01-01

    To investigate the regional changes in gray matter volume by using optimized voxel based morphometry in the whole brain of patients with Alzheimer's disease (AD) and to determine its correlation with cognitive function. Nineteen patients with AD (mean mini mental state examination (MMSE) score = 20.4) and 19 age-matched control subjects (mean MMSE score 29) participated in this prospective study. T1-weighted 3D-SPGR scans were obtained for each subject. These T1-weighted images were spatially normalized into study-specific T1 template and segmented into gray matter, white matter and CSF. After the images were modulated and smoothed, all of the gray matter images were compared with control images by using voxel-wise statistical parametric test (two-sample-test). In patients with AD, total gray matter volume was significantly smaller than normal control (552 ± 39 mL vs. 632 ± 51 mL, ρ 0.001). Significant gray matter loss was seen in both the hippocampus and amygdala complexs, and the parahippocampi and frontoparietal cortices (ρ < 0.01, family wise error corrected). Left cerebral atrophy was more prominent than the right. Loss of gray matter volume in both the superior frontal gyri and left inferior temporal gyrus had a strong correlation with lower MMSE score. Optimized VBM was able to visualize pathologic changes of AD in vivo. In AD there was widespread gray matter volume loss in the frontoparietal lobes as well as the medial temporal lobes and had a strong correlation between volume loss of specific cortical areas and MMSE score

  1. The effect of illumination on gray color

    Directory of Open Access Journals (Sweden)

    Gabriele Sperandio

    2010-01-01

    Full Text Available The present study explored the perceptual process of integration of luminance information in the production of the gray color of an object placed in an environment viewed from a window. The mean luminance of the object was varied for each mean luminance of the environment. Participants matched the gray color of the object with that of Munsell chips in a viewing box. The results show that the Munsell values so obtained are linear measures of gray color. The results support the possibility that the gray color of the object derives from an additive integration of the information about mean luminance of the object and about mean luminance of the environment, with the weights of this information varying with the mean luminances.

  2. Electrochemical conversion of micropollutants in gray water

    NARCIS (Netherlands)

    Butkovskyi, A.; Jeremiasse, A.W.; Hernandez Leal, L.; Zande, van der T.; Rijnaarts, H.; Zeeman, G.

    2014-01-01

    Electrochemical conversion of micropollutants in real gray water effluent was studied for the first time. Six compounds that are frequently found in personal care and household products, namely methylparaben, propylparaben, bisphenol A, triclosan, galaxolide, and 4- methylbenzilidene camphor

  3. Laboratory Characterization of Gray Masonry Concrete

    National Research Council Canada - National Science Library

    Williams, Erin M; Akers, Stephen A; Reed, Paul A

    2007-01-01

    Personnel of the Geotechnical and Structures Laboratory, U.S. Army Engineer Research and Development Center, conducted a laboratory investigation to characterize the strength and constitutive property behavior of a gray masonry concrete...

  4. Morphometric analysis of gray matter integrity in individuals with early-treated phenylketonuria.

    Science.gov (United States)

    Christ, Shawn E; Price, Mason H; Bodner, Kimberly E; Saville, Christopher; Moffitt, Amanda J; Peck, Dawn

    2016-05-01

    The most widely-reported neurologic finding in individuals with early-treated phenylketonuria (PKU) is abnormality in the white matter of the brain. In contrast, much less is known regarding the impact of PKU on cortical gray matter (GM) structures. Presently, we applied advanced morphometric methods to the analysis of high-resolution structural MRI images from a sample of 19 individuals with early-treated PKU and an age- and gender-matched comparison group of 22 healthy individuals without PKU. Data analysis revealed decreased GM volume in parietal cortex for the PKU group compared with the non-PKU group. A similar trend was observed for occipital GM volume. There was no evidence of group-related differences in frontal or temporal GM volume. Within the PKU group, we also found a significant relationship between blood phenylalanine levels and GM volume for select posterior cortical sub-regions. Taken together with previous research on white matter and gray matter abnormalities in PKU, the present findings point to the posterior cortices as the primary site of neurostructural changes related to early-treated PKU. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Gray matter and white matter abnormalities in online game addiction

    International Nuclear Information System (INIS)

    Weng, Chuan-Bo; Qian, Ruo-Bing; Fu, Xian-Ming; Lin, Bin; Han, Xiao-Peng; Niu, Chao-Shi; Wang, Ye-Han

    2013-01-01

    Online game addiction (OGA) has attracted greater attention as a serious public mental health issue. However, there are only a few brain magnetic resonance imaging studies on brain structure about OGA. In the current study, we used voxel-based morphometry (VBM) analysis and tract-based spatial statistics (TBSS) to investigate the microstructural changes in OGA and assessed the relationship between these morphology changes and the Young's Internet Addiction Scale (YIAS) scores within the OGA group. Compared with healthy subjects, OGA individuals showed significant gray matter atrophy in the right orbitofrontal cortex, bilateral insula, and right supplementary motor area. According to TBSS analysis, OGA subjects had significantly reduced FA in the right genu of corpus callosum, bilateral frontal lobe white matter, and right external capsule. Gray matter volumes (GMV) of the right orbitofrontal cortex, bilateral insula and FA values of the right external capsule were significantly positively correlated with the YIAS scores in the OGA subjects. Our findings suggested that microstructure abnormalities of gray and white matter were present in OGA subjects. This finding may provide more insights into the understanding of the underlying neural mechanisms of OGA

  6. Gray matter and white matter abnormalities in online game addiction

    Energy Technology Data Exchange (ETDEWEB)

    Weng, Chuan-Bo, E-mail: send007@163.com [Department of Neurosurgery, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); School of Neurosurgery, Anhui Medical University, 81 Meishang Road, Hefei, Anhui Province 230032 (China); Qian, Ruo-Bing, E-mail: rehomail@163.com [Department of Neurosurgery, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); Anhui Provincial Institute of Stereotactic Neurosurgery, 9 Lujiang Road, Hefei, Ahui Province 230001 (China); Fu, Xian-Ming, E-mail: 506537677@qq.com [Department of Neurosurgery, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); Anhui Provincial Institute of Stereotactic Neurosurgery, 9 Lujiang Road, Hefei, Ahui Province 230001 (China); Lin, Bin, E-mail: 274722758@qq.com [School of Neurosurgery, Anhui Medical University, 81 Meishang Road, Hefei, Anhui Province 230032 (China); Han, Xiao-Peng, E-mail: hanxiaopeng@163.com [Department of Psychology, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); Niu, Chao-Shi, E-mail: niuchaoshi@163.com [Department of Neurosurgery, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); Anhui Provincial Institute of Stereotactic Neurosurgery, 9 Lujiang Road, Hefei, Ahui Province 230001 (China); Wang, Ye-Han, E-mail: wangyehan@163.com [Department of Neurosurgery, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); Anhui Provincial Institute of Stereotactic Neurosurgery, 9 Lujiang Road, Hefei, Ahui Province 230001 (China)

    2013-08-15

    Online game addiction (OGA) has attracted greater attention as a serious public mental health issue. However, there are only a few brain magnetic resonance imaging studies on brain structure about OGA. In the current study, we used voxel-based morphometry (VBM) analysis and tract-based spatial statistics (TBSS) to investigate the microstructural changes in OGA and assessed the relationship between these morphology changes and the Young's Internet Addiction Scale (YIAS) scores within the OGA group. Compared with healthy subjects, OGA individuals showed significant gray matter atrophy in the right orbitofrontal cortex, bilateral insula, and right supplementary motor area. According to TBSS analysis, OGA subjects had significantly reduced FA in the right genu of corpus callosum, bilateral frontal lobe white matter, and right external capsule. Gray matter volumes (GMV) of the right orbitofrontal cortex, bilateral insula and FA values of the right external capsule were significantly positively correlated with the YIAS scores in the OGA subjects. Our findings suggested that microstructure abnormalities of gray and white matter were present in OGA subjects. This finding may provide more insights into the understanding of the underlying neural mechanisms of OGA.

  7. Gray matter and white matter abnormalities in online game addiction.

    Science.gov (United States)

    Weng, Chuan-Bo; Qian, Ruo-Bing; Fu, Xian-Ming; Lin, Bin; Han, Xiao-Peng; Niu, Chao-Shi; Wang, Ye-Han

    2013-08-01

    Online game addiction (OGA) has attracted greater attention as a serious public mental health issue. However, there are only a few brain magnetic resonance imaging studies on brain structure about OGA. In the current study, we used voxel-based morphometry (VBM) analysis and tract-based spatial statistics (TBSS) to investigate the microstructural changes in OGA and assessed the relationship between these morphology changes and the Young's Internet Addiction Scale (YIAS) scores within the OGA group. Compared with healthy subjects, OGA individuals showed significant gray matter atrophy in the right orbitofrontal cortex, bilateral insula, and right supplementary motor area. According to TBSS analysis, OGA subjects had significantly reduced FA in the right genu of corpus callosum, bilateral frontal lobe white matter, and right external capsule. Gray matter volumes (GMV) of the right orbitofrontal cortex, bilateral insula and FA values of the right external capsule were significantly positively correlated with the YIAS scores in the OGA subjects. Our findings suggested that microstructure abnormalities of gray and white matter were present in OGA subjects. This finding may provide more insights into the understanding of the underlying neural mechanisms of OGA. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  8. MQ-1C Gray Eagle Unmanned Aircraft System (MQ-1C Gray Eagle)

    Science.gov (United States)

    2015-12-01

    Range Finder /Laser Designator, Synthetic Aperture Radar/Ground Moving Target Indicator, communications relay, and Hellfire Missiles. Ground equipment...equipment strength . Each Gray Eagle company will consist of 125 soldiers within the Divisional CAB and the NTC. Each unit will have three identical...will bring these companies to full Gray Eagle System equipment strength . Each Gray Eagle company will consist of 125 soldiers within the divisional

  9. Gray matter alterations and correlation of nutritional intake with the gray matter volume in prediabetes

    OpenAIRE

    Hou, Yi-Cheng; Lai, Chien-Han; Wu, Yu-Te; Yang, Shwu-Huey

    2016-01-01

    Abstract The neurophysiology of prediabetes plays an important role in preventive medicine. The dysregulation of glucose metabolism is likely linked to changes in neuron-related gray matter. Therefore, we designed this study to investigate gray matter alterations in medication-naive prediabetic patients. We expected to find alterations in the gray matter of prediabetic patients. A total of 64 prediabetic patients and 54 controls were enrolled. All subjects received T1 scans using a 3-T magnet...

  10. Image of а head of law-enforcement body on micro level (empirical experimentation

    Directory of Open Access Journals (Sweden)

    D. G. Perednya

    2016-01-01

    Full Text Available The article determines image of the head of law-enforcement body. Subjects and objects of image are described. Inhomogenuity of image is cleared up. Method of examination is shortly micro level described. It is talking about image, which is formed in mind of members of team of law-enforcement body, who are subordinated to object of image. State-of-the-art is illustrated, according to received data. Hypothesis about negative image of the head in mind of subordinates is disproved. It is shown contradiction of images in collective mind and social mind.

  11. Use of morphologic filters in the computerized detection of lung nodules in digital chest images

    International Nuclear Information System (INIS)

    Yoshimura, H.; Giger, M.L.; Doi, K.; Ahn, N.; MacMahon, H.

    1989-01-01

    The authors have previously described a computerized scheme for the detection of lung nodules based on a difference-image approach, which had a detection accuracy of 70% with 7--8 false positives per image. Currently, they are investigating morphologic filters for the further enhancement/suppression of nodule-signals and the removal of false-positives. Gray-level morphologic filtering is performed on clinical chest radiographs digitized with an optical drum scanner. Various shapes and sequences of erosion and dilation filters (i.e., determination of the minimum and maximum gray levels, respectively) were examined for signal enhancement and suppression for sue in the difference- image approach

  12. Louis Harold Gray (1905-1965)

    International Nuclear Information System (INIS)

    Tomljenovic, I.

    2003-01-01

    15th CGPM (Conference General de Poids et Mesures) conference of 1975 accepted gray (Gy) as the unit of absorbed dose in honour of British physicist and radiation biologist Louis Harold Gray. This unit is a part of the SI system for units and measures. The idea of the article is to give a closer look into the life and work of this great scientist. (author)

  13. Image processing on the image with pixel noise bits removed

    Science.gov (United States)

    Chuang, Keh-Shih; Wu, Christine

    1992-06-01

    Our previous studies used statistical methods to assess the noise level in digital images of various radiological modalities. We separated the pixel data into signal bits and noise bits and demonstrated visually that the removal of the noise bits does not affect the image quality. In this paper we apply image enhancement techniques on noise-bits-removed images and demonstrate that the removal of noise bits has no effect on the image property. The image processing techniques used are gray-level look up table transformation, Sobel edge detector, and 3-D surface display. Preliminary results show no noticeable difference between original image and noise bits removed image using look up table operation and Sobel edge enhancement. There is a slight enhancement of the slicing artifact in the 3-D surface display of the noise bits removed image.

  14. Food Irradiation Is Done in Grays, not Rads

    International Nuclear Information System (INIS)

    Strom, Daniel J.

    2002-01-01

    One federal agency has chosen to use exclusively modern SI units of radiation dose in its regulations: the FDA. While not exactly hot news, this bold move by a U.S. government agency on November 26, 1997, should be noted by those who wish to encourage the switch from curies, working level months, rads, rems, and roentgens to becquerels, joule hours per cubic meter, grays, sieverts, and coulombs per kilogram. The regulation is 21 CFR 179, Irradiation in the Production, Processing, and Handling of Food. Specifically, 21 CFR 179.26 (b) 8. permits meat irradiation up to 4.5 kGy for refrigerated meat and 7.0 kGy for frozen meat. Prior to the 1997 addition, radiation doses had been quoted in grays (kGy) with rad (Mrad) values in parentheses. In the 1997 addition, the Mrads disappeared

  15. Selecting optimal monochromatic level with spectral CT imaging for improving imaging quality in hepatic venography

    International Nuclear Information System (INIS)

    Sun Jun; Luo Xianfu; Wang Shou'an; Wang Jun; Sun Jiquan; Wang Zhijun; Wu Jingtao

    2013-01-01

    Objective: To investigate the effect of spectral CT monochromatic images for improving imaging quality in hepatic venography. Methods: Thirty patients underwent spectral CT examination on a GE Discovery CT 750 HD scanner. During portal phase, 1.25 mm slice thickness polychromatic images and optimal monochromatic images were obtained, and volume rendering and maximum intensity projection were created to show the hepatic veins respectively. The overall imaging quality was evaluated on a five-point scale by two radiologists. Inter-observer agreement in subjective image quality grading was assessed by Kappa statistics. Paired-sample t test were used to compare hepatic vein attenuation, hepatic parenchyma attenuation, CT value difference between the hepatic vein and the liver parenchyma, image noise, vein-to-liver contrast-to-noise ratio (CNR), the image quality score of hepatic venography between the two image data sets. Results: The monochromatic images at 50 keV were found to demonstrate the best CNR for hepatic vein.The hepatic vein attenuation [(329 ± 47) HU], hepatic parenchyma attenuation [(178 ± 33) HU], CT value difference between the hepatic vein and the liver parenchyma [(151 ± 33) HU], image noise (17.33 ± 4.18), CNR (9.13 ± 2.65), the image quality score (4.2 ± 0.6) of optimal monochromatic images were significantly higher than those of polychromatic images [(149 ± 18) HU], [(107 ± 14) HU], [(43 ±11) HU], 12.55 ± 3.02, 3.53 ± 1.03, 3.1 ± 0.8 (t values were 24.79, 13.95, 18.85, 9.07, 13.25 and 12.04, respectively, P < 0.01). In the comparison of image quality, Kappa value was 0.81 with optimal monochromatic images and 0.69 with polychromatic images. Conclusion: Monochromatic images of spectral CT could improve CNR for displaying hepatic vein and improve the image quality compared to the conventional polychromatic images. (authors)

  16. MR imaging of hypoglycemic encephalopathy: lesion distribution and prognosis prediction by diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Jeong-Hyun; Kim, Young-Joo; Yoo, Won-Jong; Ihn, Yon-Kwon; Kim, Jee-Young; Kim, Bum-Soo [The Catholic University of Korea, Department of Radiology, College of Medicine, Uijongbu, Kyunggi-do (Korea); Song, Ha-Hun [Cheju Halla General Hospital, Department of Radiology, Jeju (Korea)

    2009-10-15

    The aim of this study was to evaluate the patterns of hypoglycemic encephalopathy on diffusion-weighted imaging (DWI) and the relationship between the imaging patterns and clinical outcomes. This retrospective study included 17 consecutive patients that had hypoglycemic encephalopathy with DWI abnormalities. The topographic distributions of the DWI abnormalities of the cortex, deep gray matter, and white matter structures were assessed. In addition, possible correlation between the patterns of brain injury on DWI and clinical outcomes was investigated. There were three patterns of DWI abnormalities: involvement of both gray and white matter (n=8), selective involvement of gray matter (n=4), and selective involvement of white matter (n=5). There was no significant difference in the initial blood glucose levels among patients for each of the imaging patterns. Most patients (16/17) had bilateral symmetrical abnormalities. Among patients with bilateral symmetrical gray and/or white matter injuries, one had moderate to severe disability and 14 remained in a persistent vegetative state. The two patients with a focal unilateral white matter abnormality and a localized splenial abnormality recovered without neurological deficits. The results of this study showed that white matter was more sensitive to hypoglycemia than previously thought and there was no specific association between the patterns of injury and clinical outcomes whether the cerebral cortex, deep gray matter, and/or white matter were affected. Diffuse and extensive injury observed on the DWI predicts a poor neurologic outcome in patients with hypoglycemic injuries. (orig.)

  17. Voxel-Based Morphometry and fMRI Revealed Differences in Brain Gray Matter in Breastfed and Milk Formula-Fed Children.

    Science.gov (United States)

    Ou, X; Andres, A; Pivik, R T; Cleves, M A; Snow, J H; Ding, Z; Badger, T M

    2016-04-01

    Infant diets may have significant impact on brain development in children. The aim of this study was to evaluate brain gray matter structure and function in 8-year-old children who were predominantly breastfed or fed cow's milk formula as infants. Forty-two healthy children (breastfed: n = 22, 10 boys and 12 girls; cow's milk formula: n = 20, 10 boys and 10 girls) were studied by using structural MR imaging (3D T1-weighted imaging) and blood oxygen level-dependent fMRI (while performing tasks involving visual perception and language functions). They were also administered standardized tests evaluating intelligence (Reynolds Intellectual Assessment Scales) and language skills (Clinical Evaluation of Language Fundamentals). Total brain gray matter volume did not differ between the breastfed and cow's milk formula groups. However, breastfed children had significantly higher (P left inferior temporal lobe and left superior parietal lobe compared with cow's milk formula-fed children. Breastfed children showed significantly more brain activation in the right frontal and left/right temporal lobes on fMRI when processing the perception task and in the left temporal/occipital lobe when processing the visual language task than cow's milk formula-fed children. The imaging findings were associated with significantly better performance for breastfed than cow's milk formula-fed children on both tasks. Our findings indicated greater regional gray matter development and better regional gray matter function in breastfed than cow's milk formula-fed children at 8 years of age and suggested that infant diets may have long-term influences on brain development in children. © 2016 by American Journal of Neuroradiology.

  18. Gray Matter Volume Reduction Is Associated with Cognitive Impairment in Neuromyelitis Optica.

    Science.gov (United States)

    Wang, Q; Zhang, N; Qin, W; Li, Y; Fu, Y; Li, T; Shao, J; Yang, L; Shi, F-D; Yu, C

    2015-10-01

    Whether gray matter impairment occurs in neuromyelitis optica is a matter of ongoing debate, and the association of gray matter impairment with cognitive deficits remains largely unknown. The purpose of this study was to investigate gray matter volume reductions and their association with cognitive decline in patients with neuromyelitis optica. This study included 50 patients with neuromyelitis optica and 50 sex-, age-, handedness-, and education-matched healthy subjects who underwent high-resolution structural MR imaging examinations and a battery of cognitive assessments. Gray matter volume and cognitive differences were compared between the 2 groups. The correlations of the regional gray matter volume with cognitive scores and clinical variables were explored in the patients with neuromyelitis optica. Compared with healthy controls (635.9 ± 51.18 mL), patients with neuromyelitis optica (602.8 ± 51.03 mL) had a 5.21% decrease in the mean gray matter volume of the whole brain (P optica affected the frontal and temporal cortices and the right thalamus (false discovery rate correction, P optica (Alphasim correction, P optica had impairments in memory, information processing speed, and verbal fluency (P optica and is associated with cognitive impairment and disease severity in this group. © 2015 by American Journal of Neuroradiology.

  19. A tensor based morphometry study of longitudinal gray matter contraction in FTD

    Science.gov (United States)

    Brambati, Simona M.; Renda, Natasha C.; Rankin, Katherine P.; Rosen, Howard J.; Seeley, William W.; Ashburner, John; Weiner, Michael W.; Miller, Bruce L.; Gorno-Tempini, Maria Luisa

    2008-01-01

    Frontotemporal dementia (FTD) is a neurodegenerative disease characterized by progressive behavioural abnormalities and frontotemporal atrophy. Here we used tensor based morphometry (TBM) to identify regions of longitudinal progression of gray matter atrophy in FTD compared to controls. T1-weighted MRI images were acquired at presentation and 1-year follow-up from 12 patients with mild to moderate FTD and 12 healthy controls. Using TBM as implemented in SPM2, a voxel-wise estimation of regional tissue volume change was derived from the deformation field required to warp a subject’s late to early anatomical images. A whole brain analysis was performed, in which a level of significance of pBased on prior studies, a region of interest (ROI) analysis was also performed, including in the search area bilateral medial and orbital frontal regions, anterior cingulate gyrus, insula, amygdala and hippocampus. Within this ROI a level of significance of p<0.001 uncorrected was accepted. In the whole brain analysis, the anterior cingulate/paracingulate gyri were the only regions that showed significant atrophy change over 1 year. In the ROI analysis, the left ventro-medial frontal cortex, right medial superior frontal gyrus, anterior insulae and left amygdala/hippocampus showed significant longitudinal changes. In conclusion, limbic and paralimbic regions showed detectable gray matter contraction over 1 year in FTD, confirming the susceptibility of these regions to the disease and the consistency with their putative role in causing typical presenting behaviours. These results suggest that TBM might be useful in tracking progression of regional atrophy in FTD. PMID:17350290

  20. SENTINEL-2 LEVEL 1 PRODUCTS AND IMAGE PROCESSING PERFORMANCES

    OpenAIRE

    S. J. Baillarin; A. Meygret; C. Dechoz; B. Petrucci; S. Lacherade; T. Tremas; C. Isola; P. Martimort; F. Spoto

    2012-01-01

    In partnership with the European Commission and in the frame of the Global Monitoring for Environment and Security (GMES) program, the European Space Agency (ESA) is developing the Sentinel-2 optical imaging mission devoted to the operational monitoring of land and coastal areas. The Sentinel-2 mission is based on a satellites constellation deployed in polar sun-synchronous orbit. While ensuring data continuity of former SPOT and LANDSAT multi-spectral missions, Sentinel-2 wil...

  1. TRADEMARK IMAGE RETRIEVAL USING LOW LEVEL FEATURE EXTRACTION IN CBIR

    OpenAIRE

    Latika Pinjarkar*, Manisha Sharma, Smita Selot

    2016-01-01

    Trademarks work as significant responsibility in industry and commerce. Trademarks are important component of its industrial property, and violation can have severe penalty. Therefore designing an efficient trademark retrieval system and its assessment for uniqueness is thus becoming very important task now a days. Trademark image retrieval system where a new candidate trademark is compared with already registered trademarks to check that there is no possibility of resembl...

  2. Scanning ion images; analysis of pharmaceutical drugs at organelle levels

    Science.gov (United States)

    Larras-Regard, E.; Mony, M.-C.

    1995-05-01

    With the ion analyser IMS 4F used in microprobe mode, it is possible to obtain images of fields of 10 × 10 [mu]m2, corresponding to an effective magnification of 7000 with lateral resolution of 250 nm, technical characteristics that are appropriate for the size of cell organelles. It is possible to characterize organelles by their relative CN-, P- and S- intensities when the tissues are prepared by freeze fixation and freeze substitution. The recognition of organelles enables correlation of the tissue distribution of ebselen, a pharmaceutical drug containing selenium. The various metabolites characterized in plasma, bile and urine during biotransformation of ebselen all contain selenium, so the presence of the drug and its metabolites can be followed by images of Se. We were also able to detect the endogenous content of Se in tissue, due to the increased sensitivity of ion analysis in microprobe mode. Our results show a natural occurrence of Se in the border corresponding to the basal lamina of cells of proximal but not distal tubules of the kidney. After treatment of rats with ebselen, an additional site of Se is found in the lysosomes. We suggest that in addition to direct elimination of ebselen and its metabolites by glomerular filtration and urinary elimination, a second process of elimination may occur: Se compounds reaching the epithelial cells via the basal lamina accumulate in lysosomes prior to excretion into the tubular fluid. The technical developments of using the IMS 4F instrument in the microprobe mode and the improvement in preparation of samples by freeze fixation and substitution further extend the limit of ion analysis in biology. Direct imaging of trace elements and molecules marked with a tracer make it possible to determine their targets by comparison with images of subcellular structures. This is a promising advance in the study of pathways of compounds within tissues, cells and the whole organism.

  3. A Study of Light Level Effect on the Accuracy of Image Processing-based Tomato Grading

    Science.gov (United States)

    Prijatna, D.; Muhaemin, M.; Wulandari, R. P.; Herwanto, T.; Saukat, M.; Sugandi, W. K.

    2018-05-01

    Image processing method has been used in non-destructive tests of agricultural products. Compared to manual method, image processing method may produce more objective and consistent results. Image capturing box installed in currently used tomato grading machine (TEP-4) is equipped with four fluorescence lamps to illuminate the processed tomatoes. Since the performance of any lamp will decrease if its service time has exceeded its lifetime, it is predicted that this will affect tomato classification. The objective of this study was to determine the minimum light levels which affect classification accuracy. This study was conducted by varying light level from minimum and maximum on tomatoes in image capturing boxes and then investigates its effects on image characteristics. Research results showed that light intensity affects two variables which are important for classification, for example, area and color of captured image. Image processing program was able to determine correctly the weight and classification of tomatoes when light level was 30 lx to 140 lx.

  4. LSB-Based Steganography Using Reflected Gray Code

    Science.gov (United States)

    Chen, Chang-Chu; Chang, Chin-Chen

    Steganography aims to hide secret data into an innocuous cover-medium for transmission and to make the attacker cannot recognize the presence of secret data easily. Even the stego-medium is captured by the eavesdropper, the slight distortion is hard to be detected. The LSB-based data hiding is one of the steganographic methods, used to embed the secret data into the least significant bits of the pixel values in a cover image. In this paper, we propose an LSB-based scheme using reflected-Gray code, which can be applied to determine the embedded bit from secret information. Following the transforming rule, the LSBs of stego-image are not always equal to the secret bits and the experiment shows that the differences are up to almost 50%. According to the mathematical deduction and experimental results, the proposed scheme has the same image quality and payload as the simple LSB substitution scheme. In fact, our proposed data hiding scheme in the case of G1 (one bit Gray code) system is equivalent to the simple LSB substitution scheme.

  5. Imaging network level language recovery after left PCA stroke.

    Science.gov (United States)

    Sebastian, Rajani; Long, Charltien; Purcell, Jeremy J; Faria, Andreia V; Lindquist, Martin; Jarso, Samson; Race, David; Davis, Cameron; Posner, Joseph; Wright, Amy; Hillis, Argye E

    2016-05-11

    The neural mechanisms that support aphasia recovery are not yet fully understood. Our goal was to evaluate longitudinal changes in naming recovery in participants with posterior cerebral artery (PCA) stroke using a case-by-case analysis. Using task based and resting state functional magnetic resonance imaging (fMRI) and detailed language testing, we longitudinally studied the recovery of the naming network in four participants with PCA stroke with naming deficits at the acute (0 week), sub acute (3-5 weeks), and chronic time point (5-7 months) post stroke. Behavioral and imaging analyses (task related and resting state functional connectivity) were carried out to elucidate longitudinal changes in naming recovery. Behavioral and imaging analysis revealed that an improvement in naming accuracy from the acute to the chronic stage was reflected by increased connectivity within and between left and right hemisphere "language" regions. One participant who had persistent moderate naming deficit showed weak and decreasing connectivity longitudinally within and between left and right hemisphere language regions. These findings emphasize a network view of aphasia recovery, and show that the degree of inter- and intra- hemispheric balance between the language-specific regions is necessary for optimal recovery of naming, at least in participants with PCA stroke.

  6. Differential regional gray matter volumes in patients with on-line game addiction and professional gamers.

    Science.gov (United States)

    Han, Doug Hyun; Lyoo, In Kyoon; Renshaw, Perry F

    2012-04-01

    Patients with on-line game addiction (POGA) and professional video game players play video games for extended periods of time, but experience very different consequences for their on-line game play. Brain regions consisting of anterior cingulate, thalamus and occpito-temporal areas may increase the likelihood of becoming a pro-gamer or POGA. Twenty POGA, seventeen pro-gamers, and eighteen healthy comparison subjects (HC) were recruited. All magnetic resonance imaging (MRI) was performed on a 1.5 Tesla Espree MRI scanner (SIEMENS, Erlangen, Germany). Voxel-wise comparisons of gray matter volume were performed between the groups using the two-sample t-test with statistical parametric mapping (SPM5). Compared to HC, the POGA group showed increased impulsiveness and perseverative errors, and volume in left thalamus gray matter, but decreased gray matter volume in both inferior temporal gyri, right middle occipital gyrus, and left inferior occipital gyrus, compared with HC. Pro-gamers showed increased gray matter volume in left cingulate gyrus, but decreased gray matter volume in left middle occipital gyrus and right inferior temporal gyrus compared with HC. Additionally, the pro-gamer group showed increased gray matter volume in left cingulate gyrus and decreased left thalamus gray matter volume compared with the POGA group. The current study suggests that increased gray matter volumes of the left cingulate gyrus in pro-gamers and of the left thalamus in POGA may contribute to the different clinical characteristics of pro-gamers and POGA. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Cost Comparison of Conventional Gray Combined Sewer Overflow Control Infrastructure versus a Green/Gray Combination

    Science.gov (United States)

    This paper outlines a life-cycle cost analysis comparing a green (rain gardens) and gray (tunnels) infrastructure combination to a gray-only option to control combined sewer overflow in the Turkey Creek Combined Sewer Overflow Basin, in Kansas City, MO. The plan area of this Bas...

  8. Low-Level Color and Texture Feature Extraction of Coral Reef Components

    Directory of Open Access Journals (Sweden)

    Ma. Sheila Angeli Marcos

    2003-06-01

    Full Text Available The purpose of this study is to develop a computer-based classifier that automates coral reef assessmentfrom digitized underwater video. We extract low-level color and texture features from coral images toserve as input to a high-level classifier. Low-level features for color were labeled blue, green, yellow/brown/orange, and gray/white, which are described by the normalized chromaticity histograms of thesemajor colors. The color matching capability of these features was determined through a technique called“Histogram Backprojection”. The low-level texture feature marks a region as coarse or fine dependingon the gray-level variance of the region.

  9. Effect of blood glucose level on 18F-FDG PET/CT imaging

    International Nuclear Information System (INIS)

    Tan Haibo; Lin Xiangtong; Guan Yihui; Zhao Jun; Zuo Chuantao; Hua Fengchun; Tang Wenying

    2008-01-01

    Objective: The aim of this study was to investigate the effect of blood glucose level on the image quality of 18 F-fluorodeoxyglucose (FDG) PET/CT imaging. Methods: Eighty patients referred to the authors' department for routine whole-body 18 F-FDG PET/CT check up were recruited into this study. The patients were classified into 9 groups according to their blood glucose level: normal group avg and SUV max ) of liver on different slices. SPSS 12.0 was used to analyse the data. Results: (1) There were significant differences among the 9 groups in image quality scores and image noises (all P avg and SUV max : 0.60 and 0.33, P<0.05). Conclusions: The higher the blood glucose level, the worse the image quality. When the blood glucose level is more than or equal to 12.0 mmol/L, the image quality will significantly degrade. (authors)

  10. Multimodal MEMPRAGE, FLAIR, and R2* Segmentation to Resolve Dura and Vessels from Cortical Gray Matter

    Directory of Open Access Journals (Sweden)

    Roberto Viviani

    2017-05-01

    Full Text Available While widely in use in automated segmentation approaches for the detection of group differences or of changes associated with continuous predictors in gray matter volume, T1-weighted images are known to represent dura and cortical vessels with signal intensities similar to those of gray matter. By considering multiple signal sources at once, multimodal segmentation approaches may be able to resolve these different tissue classes and address this potential confound. We explored here the simultaneous use of FLAIR and apparent transverse relaxation rates (a signal related to T2* relaxation maps and having similar contrast with T1-weighted images. Relative to T1-weighted images alone, multimodal segmentation had marked positive effects on 1. the separation of gray matter from dura, 2. the exclusion of vessels from the gray matter compartment, and 3. the contrast with extracerebral connective tissue. While obtainable together with the T1-weighted images without increasing scanning times, apparent transverse relaxation rates were less effective than added FLAIR images in providing the above mentioned advantages. FLAIR images also improved the detection of cortical matter in areas prone to susceptibility artifacts in standard MPRAGE T1-weighted images, while the addition of transverse relaxation maps exacerbated the effect of these artifacts on segmentation. Our results confirm that standard MPRAGE segmentation may overestimate gray matter volume by wrongly assigning vessels and dura to this compartment and show that multimodal approaches may greatly improve the specificity of cortical segmentation. Since multimodal segmentation is easily implemented, these benefits are immediately available to studies focusing on translational applications of structural imaging.

  11. Reducing surgical levels by paraspinal mapping and diffusion tensor imaging techniques in lumbar spinal stenosis

    OpenAIRE

    Chen, Hua-Biao; Wan, Qi; Xu, Qi-Feng; Chen, Yi; Bai, Bo

    2016-01-01

    Background Correlating symptoms and physical examination findings with surgical levels based on common imaging results is not reliable. In patients who have no concordance between radiological and clinical symptoms, the surgical levels determined by conventional magnetic resonance imaging (MRI) and neurogenic examination (NE) may lead to a more extensive surgery and significant complications. We aimed to confirm that whether the use of diffusion tensor imaging (DTI) and paraspinal mapping (PM...

  12. Unsupervised Performance Evaluation of Image Segmentation

    Directory of Open Access Journals (Sweden)

    Chabrier Sebastien

    2006-01-01

    Full Text Available We present in this paper a study of unsupervised evaluation criteria that enable the quantification of the quality of an image segmentation result. These evaluation criteria compute some statistics for each region or class in a segmentation result. Such an evaluation criterion can be useful for different applications: the comparison of segmentation results, the automatic choice of the best fitted parameters of a segmentation method for a given image, or the definition of new segmentation methods by optimization. We first present the state of art of unsupervised evaluation, and then, we compare six unsupervised evaluation criteria. For this comparative study, we use a database composed of 8400 synthetic gray-level images segmented in four different ways. Vinet's measure (correct classification rate is used as an objective criterion to compare the behavior of the different criteria. Finally, we present the experimental results on the segmentation evaluation of a few gray-level natural images.

  13. Automatic anatomically selective image enhancement in digital chest radiography

    International Nuclear Information System (INIS)

    Sezan, M.I.; Minerbo, G.N.; Schaetzing, R.

    1989-01-01

    The authors develop a technique for automatic anatomically selective enhancement of digital chest radiographs. Anatomically selective enhancement is motivated by the desire to simultaneously meet the different enhancement requirements of the lung field and the mediastinum. A recent peak detection algorithm and a set of rules are applied to the image histogram to determine automatically a gray-level threshold between the lung field and mediastinum. The gray-level threshold facilitates anatomically selective gray-scale modification and/or unsharp masking. Further, in an attempt to suppress possible white-band or black-band artifacts due to unsharp masking at sharp edges, local-contrast adaptivity is incorporated into anatomically selective unsharp masking by designing an anatomy-sensitive emphasis parameter which varies asymmetrically with positive and negative values of the local image contrast

  14. [A voxel-based morphometric analysis of brain gray matter in online game addicts].

    Science.gov (United States)

    Weng, Chuan-bo; Qian, Ruo-bing; Fu, Xian-ming; Lin, Bin; Ji, Xue-bing; Niu, Chao-shi; Wang, Ye-han

    2012-12-04

    To explore the possible brain mechanism of online game addiction (OGA) in terms of brain morphology through voxel-based morphometric (VBM) analysis. Seventeen subjects with OGA and 17 age- and gender-matched healthy controls (HC group) were recruited from Department of Psychology at our hospital during February-December 2011. The internet addiction scale (IAS) was used to measure the degree of OGA tendency. Magnetic resonance imaging (MRI) scans were performed to acquire 3-dimensional T1-weighted images. And FSL 4.1 software was employed to confirm regional gray matter volume changes. For the regions where OGA subjects showed significantly different gray matter volumes from the controls, the gray matter volumes of these areas were extracted, averaged and regressed against the scores of IAS. The OGA group had lower gray matter volume in left orbitofrontal cortex (OFC), left medial prefrontal cortex (mPFC), bilateral insula (INS), left posterior cingulate cortex (PCC) and left supplementary motor area (SMA). Gray matter volumes of left OFC and bilateral INS showed a negative correlation with the scores of IAS (r = -0.65, r = -0.78, P online game addicts and they may be correlated with the occurrence and maintenance of OGA.

  15. Surface-based reconstruction and diffusion MRI in the assessment of gray and white matter damage in multiple sclerosis

    Science.gov (United States)

    Caffini, Matteo; Bergsland, Niels; LaganÃ, Marcella; Tavazzi, Eleonora; Tortorella, Paola; Rovaris, Marco; Baselli, Giuseppe

    2014-03-01

    Despite advances in the application of nonconventional MRI techniques in furthering the understanding of multiple sclerosis pathogenic mechanisms, there are still many unanswered questions, such as the relationship between gray and white matter damage. We applied a combination of advanced surface-based reconstruction and diffusion tensor imaging techniques to address this issue. We found significant relationships between white matter tract integrity indices and corresponding cortical structures. Our results suggest a direct link between damage in white and gray matter and contribute to the notion of gray matter loss relating to clinical disability.

  16. Robust boundary detection of left ventricles on ultrasound images using ASM-level set method.

    Science.gov (United States)

    Zhang, Yaonan; Gao, Yuan; Li, Hong; Teng, Yueyang; Kang, Yan

    2015-01-01

    Level set method has been widely used in medical image analysis, but it has difficulties when being used in the segmentation of left ventricular (LV) boundaries on echocardiography images because the boundaries are not very distinguish, and the signal-to-noise ratio of echocardiography images is not very high. In this paper, we introduce the Active Shape Model (ASM) into the traditional level set method to enforce shape constraints. It improves the accuracy of boundary detection and makes the evolution more efficient. The experiments conducted on the real cardiac ultrasound image sequences show a positive and promising result.

  17. Study of the Gray Scale, Polychromatic, Distortion Invariant Neural Networks Using the Ipa Model.

    Science.gov (United States)

    Uang, Chii-Maw

    Research in the optical neural network field is primarily motivated by the fact that humans recognize objects better than the conventional digital computers and the massively parallel inherent nature of optics. This research represents a continuous effort during the past several years in the exploitation of using neurocomputing for pattern recognition. Based on the interpattern association (IPA) model and Hamming net model, many new systems and applications are introduced. A gray level discrete associative memory that is based on object decomposition/composition is proposed for recognizing gray-level patterns. This technique extends the processing ability from the binary mode to gray-level mode, and thus the information capacity is increased. Two polychromatic optical neural networks using color liquid crystal television (LCTV) panels for color pattern recognition are introduced. By introducing a color encoding technique in conjunction with the interpattern associative algorithm, a color associative memory was realized. Based on the color decomposition and composition technique, a color exemplar-based Hamming net was built for color image classification. A shift-invariant neural network is presented through use of the translation invariant property of the modulus of the Fourier transformation and the hetero-associative interpattern association (IPA) memory. To extract the main features, a quadrantal sampling method is used to sampled data and then replace the training patterns. Using the concept of hetero-associative memory to recall the distorted object. A shift and rotation invariant neural network using an interpattern hetero-association (IHA) model is presented. To preserve the shift and rotation invariant properties, a set of binarized-encoded circular harmonic expansion (CHE) functions at the Fourier domain is used as the training set. We use the shift and symmetric properties of the modulus of the Fourier spectrum to avoid the problem of centering the CHE

  18. Subpixel level mapping of remotely sensed image using colorimetry

    Directory of Open Access Journals (Sweden)

    M. Suresh

    2018-04-01

    Full Text Available The problem of extracting proportion of classes present within a pixel has been a challenge for researchers for which already numerous methodologies have been developed but still saturation is far ahead, since still the methods accounting these mixed classes are not perfect and they would never be perfect until one can talk about one to one correspondence for each pixel and ground data, which is practically impossible. In this paper a step towards generation of new method for finding out mixed class proportions in a pixel on the basis of the mixing property of colors as per colorimetry. The methodology involves locating the class color of a mixed pixel on chromaticity diagram and then using contextual information mainly the location of neighboring pixels on chromaticity diagram to estimate the proportion of classes in the mixed pixel.Also the resampling method would be more accurate when accounting for sharp and exact boundaries. With the usage of contextual information can generate the resampled image containing only the colors which really exist. The process is simply accounting the fraction and then the number of pixels by multiplying the fraction by total number of pixels into which one pixel is splitted to get number of pixels of each color based on contextual information. Keywords: Subpixel classification, Remote sensing imagery, Colorimetric color space, Sampling and subpixel mapping

  19. Simultaneous reconstruction, segmentation, and edge enhancement of relatively piecewise continuous images with intensity-level information

    International Nuclear Information System (INIS)

    Liang, Z.; Jaszczak, R.; Coleman, R.; Johnson, V.

    1991-01-01

    A multinomial image model is proposed which uses intensity-level information for reconstruction of contiguous image regions. The intensity-level information assumes that image intensities are relatively constant within contiguous regions over the image-pixel array and that intensity levels of these regions are determined either empirically or theoretically by information criteria. These conditions may be valid, for example, for cardiac blood-pool imaging, where the intensity levels (or radionuclide activities) of myocardium, blood-pool, and background regions are distinct and the activities within each region of muscle, blood, or background are relatively uniform. To test the model, a mathematical phantom over a 64x64 array was constructed. The phantom had three contiguous regions. Each region had a different intensity level. Measurements from the phantom were simulated using an emission-tomography geometry. Fifty projections were generated over 180 degree, with 64 equally spaced parallel rays per projection. Projection data were randomized to contain Poisson noise. Image reconstructions were performed using an iterative maximum a posteriori probability procedure. The contiguous regions corresponding to the three intensity levels were automatically segmented. Simultaneously, the edges of the regions were sharpened. Noise in the reconstructed images was significantly suppressed. Convergence of the iterative procedure to the phantom was observed. Compared with maximum likelihood and filtered-backprojection approaches, the results obtained using the maximum a posteriori probability with the intensity-level information demonstrated qualitative and quantitative improvement in localizing the regions of varying intensities

  20. Influence of parameter settings in voxel-based morphometry 8. Using DARTEL and region-of-interest on reproducibility in gray matter volumetry.

    Science.gov (United States)

    Goto, M; Abe, O; Aoki, S; Hayashi, N; Miyati, T; Takao, H; Matsuda, H; Yamashita, F; Iwatsubo, T; Mori, H; Kunimatsu, A; Ino, K; Yano, K; Ohtomo, K

    2015-01-01

    To investigate whether reproducibility of gray matter volumetry is influenced by parameter settings for VBM 8 using Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) with region-of-interest (ROI) analyses. We prepared three-dimensional T1-weighted magnetic resonance images (3D-T1WIs) of 21 healthy subjects. All subjects were imaged with each of five MRI systems. Voxel-based morphometry 8 (VBM 8) and WFU PickAtlas software were used for gray matter volumetry. The bilateral ROI labels used were those provided as default settings with the software: Frontal Lobe, Hippocampus, Occipital Lobe, Orbital Gyrus, Parietal Lobe, Putamen, and Temporal Lobe. All 3D-T1WIs were segmented to gray matter with six parameters of VBM 8, with each parameter having between three and eight selectable levels. Reproducibility was evaluated as the standard deviation (mm³) of measured values for the five MRI systems. Reproducibility was influenced by 'Bias regularization (BiasR)', 'Bias FWHM', and 'De-noising filter' settings, but not by 'MRF weighting', 'Sampling distance', or 'Warping regularization' settings. Reproducibility in BiasR was influenced by ROI. Superior reproducibility was observed in Frontal Lobe with the BiasR1 setting, and in Hippocampus, Parietal Lobe, and Putamen with the BiasR3*, BiasR1, and BiasR5 settings, respectively. Reproducibility of gray matter volumetry was influenced by parameter settings in VBM 8 using DARTEL and ROI. In multi-center studies, the use of appropriate settings in VBM 8 with DARTEL results in reduced scanner effect.

  1. Habitat selection and diurnal refugia of gray foxes in southwestern Georgia, USA.

    Directory of Open Access Journals (Sweden)

    Nicholas R Deuel

    Full Text Available Understanding habitat selection of gray foxes (Urocyon cinereoargenteus is essential to evaluate their potential response to changes in land use and predator communities. Few studies have evaluated temporal habitat selection or explicitly identified habitats used by gray foxes for diurnal refugia. We used GPS collars to obtain location data for 34 gray foxes (20 males and 14 females from February 2014 to December 2015 to evaluate temporal (seasonal and diel habitat selection and selection of diurnal refugia in southwestern Georgia, USA. We analyzed habitat selection at 2 levels, selection of a core area within the home range and selection of locations within the home range. Habitat selection was non-random (P 0.05. Hardwoods, human use (i.e., areas associated with regular human activity such as buildings, lawns, parking areas, etc., and roads were selected (P 0.05. Selection of habitats for diurnal refugia did not vary seasonally or by sex (P > 0.05, with foxes selecting (P < 0.05 areas near hardwood forests, roads, agriculture, human use, pastures/food plots, and shrub scrub habitats. Gray foxes were observed on the ground while resting, and we found no evidence of gray foxes diurnally resting in trees. Our results suggest that on our study area, gray foxes are an edge species that prefer forests with a hardwood component in areas near human use and roads.

  2. Graphical user interface to optimize image contrast parameters used in object segmentation - biomed 2009.

    Science.gov (United States)

    Anderson, Jeffrey R; Barrett, Steven F

    2009-01-01

    Image segmentation is the process of isolating distinct objects within an image. Computer algorithms have been developed to aid in the process of object segmentation, but a completely autonomous segmentation algorithm has yet to be developed [1]. This is because computers do not have the capability to understand images and recognize complex objects within the image. However, computer segmentation methods [2], requiring user input, have been developed to quickly segment objects in serial sectioned images, such as magnetic resonance images (MRI) and confocal laser scanning microscope (CLSM) images. In these cases, the segmentation process becomes a powerful tool in visualizing the 3D nature of an object. The user input is an important part of improving the performance of many segmentation methods. A double threshold segmentation method has been investigated [3] to separate objects in gray scaled images, where the gray level of the object is among the gray levels of the background. In order to best determine the threshold values for this segmentation method the image must be manipulated for optimal contrast. The same is true of other segmentation and edge detection methods as well. Typically, the better the image contrast, the better the segmentation results. This paper describes a graphical user interface (GUI) that allows the user to easily change image contrast parameters that will optimize the performance of subsequent object segmentation. This approach makes use of the fact that the human brain is extremely effective in object recognition and understanding. The GUI provides the user with the ability to define the gray scale range of the object of interest. These lower and upper bounds of this range are used in a histogram stretching process to improve image contrast. Also, the user can interactively modify the gamma correction factor that provides a non-linear distribution of gray scale values, while observing the corresponding changes to the image. This

  3. Deep gray matter demyelination detected by magnetization transfer ratio in the cuprizone model.

    Directory of Open Access Journals (Sweden)

    Sveinung Fjær

    Full Text Available In multiple sclerosis (MS, the correlation between lesion load on conventional magnetic resonance imaging (MRI and clinical disability is weak. This clinico-radiological paradox might partly be due to the low sensitivity of conventional MRI to detect gray matter demyelination. Magnetization transfer ratio (MTR has previously been shown to detect white matter demyelination in mice. In this study, we investigated whether MTR can detect gray matter demyelination in cuprizone exposed mice. A total of 54 female C57BL/6 mice were split into one control group ( and eight cuprizone exposed groups ([Formula: see text]. The mice were exposed to [Formula: see text] (w/w cuprizone for up to six weeks. MTR images were obtained at a 7 Tesla Bruker MR-scanner before cuprizone exposure, weekly for six weeks during cuprizone exposure, and once two weeks after termination of cuprizone exposure. Immunohistochemistry staining for myelin (anti-Proteolopid Protein and oligodendrocytes (anti-Neurite Outgrowth Inhibitor Protein A was obtained after each weekly scanning. Rates of MTR change and correlations between MTR values and histological findings were calculated in five brain regions. In the corpus callosum and the deep gray matter a significant rate of MTR value decrease was found, [Formula: see text] per week ([Formula: see text] and [Formula: see text] per week ([Formula: see text] respectively. The MTR values correlated to myelin loss as evaluated by immunohistochemistry (Corpus callosum: [Formula: see text]. Deep gray matter: [Formula: see text], but did not correlate to oligodendrocyte density. Significant results were not found in the cerebellum, the olfactory bulb or the cerebral cortex. This study shows that MTR can be used to detect demyelination in the deep gray matter, which is of particular interest for imaging of patients with MS, as deep gray matter demyelination is common in MS, and is not easily detected on conventional clinical MRI.

  4. A Variational Level Set Approach Based on Local Entropy for Image Segmentation and Bias Field Correction.

    Science.gov (United States)

    Tang, Jian; Jiang, Xiaoliang

    2017-01-01

    Image segmentation has always been a considerable challenge in image analysis and understanding due to the intensity inhomogeneity, which is also commonly known as bias field. In this paper, we present a novel region-based approach based on local entropy for segmenting images and estimating the bias field simultaneously. Firstly, a local Gaussian distribution fitting (LGDF) energy function is defined as a weighted energy integral, where the weight is local entropy derived from a grey level distribution of local image. The means of this objective function have a multiplicative factor that estimates the bias field in the transformed domain. Then, the bias field prior is fully used. Therefore, our model can estimate the bias field more accurately. Finally, minimization of this energy function with a level set regularization term, image segmentation, and bias field estimation can be achieved. Experiments on images of various modalities demonstrated the superior performance of the proposed method when compared with other state-of-the-art approaches.

  5. Response to Biber, Gray, and Poonpon (2011)

    Science.gov (United States)

    Yang, WeiWei

    2013-01-01

    The recent "TESOL Quarterly" article by Biber, Gray, and Poonpon (2011) raises important considerations with respect to the use of syntactic complexity (SC) measures in second language (L2) studies. The article draws the field's attention to one particular measure--complexity of noun phrases (NP) (i.e., noun phrases with modifiers, such as…

  6. The Return to Gray Flannel Thinking.

    Science.gov (United States)

    Shields, James J., Jr.

    1979-01-01

    The liberal mood of the 1960s has given way to a conservatism reminiscent of the gray flannel thinking of the 1950s. Today's young people are cautious, cynical, and dead serious about personal survival. Innovation and liberalism in education are being replaced by fiscal conservatism and emphasis on standards. (Author/SJL)

  7. Chapter 17. Information needs: Great gray owls

    Science.gov (United States)

    Gregory D. Hayward

    1994-01-01

    Current understanding of great gray owl biology and ecology is based on studies of less than five populations. In an ideal world, a strong conservation strategy would require significant new information. However, current knowledge suggests that conservation of this forest owl should involve fewer conflicts than either the boreal or flammulated owl. The mix of forest...

  8. Improved detection probability of low level light and infrared image fusion system

    Science.gov (United States)

    Luo, Yuxiang; Fu, Rongguo; Zhang, Junju; Wang, Wencong; Chang, Benkang

    2018-02-01

    Low level light(LLL) image contains rich information on environment details, but is easily affected by the weather. In the case of smoke, rain, cloud or fog, much target information will lose. Infrared image, which is from the radiation produced by the object itself, can be "active" to obtain the target information in the scene. However, the image contrast and resolution is bad, the ability of the acquisition of target details is very poor, and the imaging mode does not conform to the human visual habit. The fusion of LLL and infrared image can make up for the deficiency of each sensor and give play to the advantages of single sensor. At first, we show the hardware design of fusion circuit. Then, through the recognition probability calculation of the target(one person) and the background image(trees), we find that the trees detection probability of LLL image is higher than that of the infrared image, and the person detection probability of the infrared image is obviously higher than that of LLL image. The detection probability of fusion image for one person and trees is higher than that of single detector. Therefore, image fusion can significantly enlarge recognition probability and improve detection efficiency.

  9. Haralick texture features from apparent diffusion coefficient (ADC) MRI images depend on imaging and pre-processing parameters.

    Science.gov (United States)

    Brynolfsson, Patrik; Nilsson, David; Torheim, Turid; Asklund, Thomas; Karlsson, Camilla Thellenberg; Trygg, Johan; Nyholm, Tufve; Garpebring, Anders

    2017-06-22

    In recent years, texture analysis of medical images has become increasingly popular in studies investigating diagnosis, classification and treatment response assessment of cancerous disease. Despite numerous applications in oncology and medical imaging in general, there is no consensus regarding texture analysis workflow, or reporting of parameter settings crucial for replication of results. The aim of this study was to assess how sensitive Haralick texture features of apparent diffusion coefficient (ADC) MR images are to changes in five parameters related to image acquisition and pre-processing: noise, resolution, how the ADC map is constructed, the choice of quantization method, and the number of gray levels in the quantized image. We found that noise, resolution, choice of quantization method and the number of gray levels in the quantized images had a significant influence on most texture features, and that the effect size varied between different features. Different methods for constructing the ADC maps did not have an impact on any texture feature. Based on our results, we recommend using images with similar resolutions and noise levels, using one quantization method, and the same number of gray levels in all quantized images, to make meaningful comparisons of texture feature results between different subjects.

  10. Quantum Image Encryption Algorithm Based on Image Correlation Decomposition

    Science.gov (United States)

    Hua, Tianxiang; Chen, Jiamin; Pei, Dongju; Zhang, Wenquan; Zhou, Nanrun

    2015-02-01

    A novel quantum gray-level image encryption and decryption algorithm based on image correlation decomposition is proposed. The correlation among image pixels is established by utilizing the superposition and measurement principle of quantum states. And a whole quantum image is divided into a series of sub-images. These sub-images are stored into a complete binary tree array constructed previously and then randomly performed by one of the operations of quantum random-phase gate, quantum revolving gate and Hadamard transform. The encrypted image can be obtained by superimposing the resulting sub-images with the superposition principle of quantum states. For the encryption algorithm, the keys are the parameters of random phase gate, rotation angle, binary sequence and orthonormal basis states. The security and the computational complexity of the proposed algorithm are analyzed. The proposed encryption algorithm can resist brute force attack due to its very large key space and has lower computational complexity than its classical counterparts.

  11. Bit-level plane image encryption based on coupled map lattice with time-varying delay

    Science.gov (United States)

    Lv, Xiupin; Liao, Xiaofeng; Yang, Bo

    2018-04-01

    Most of the existing image encryption algorithms had two basic properties: confusion and diffusion in a pixel-level plane based on various chaotic systems. Actually, permutation in a pixel-level plane could not change the statistical characteristics of an image, and many of the existing color image encryption schemes utilized the same method to encrypt R, G and B components, which means that the three color components of a color image are processed three times independently. Additionally, dynamical performance of a single chaotic system degrades greatly with finite precisions in computer simulations. In this paper, a novel coupled map lattice with time-varying delay therefore is applied in color images bit-level plane encryption to solve the above issues. Spatiotemporal chaotic system with both much longer period in digitalization and much excellent performances in cryptography is recommended. Time-varying delay embedded in coupled map lattice enhances dynamical behaviors of the system. Bit-level plane image encryption algorithm has greatly reduced the statistical characteristics of an image through the scrambling processing. The R, G and B components cross and mix with one another, which reduces the correlation among the three components. Finally, simulations are carried out and all the experimental results illustrate that the proposed image encryption algorithm is highly secure, and at the same time, also demonstrates superior performance.

  12. Gray matter morphological anomalies in the cerebellar vermis in first-episode schizophrenia patients with cognitive deficits.

    Science.gov (United States)

    Wang, Jingjuan; Zhou, Li; Cui, Chunlei; Liu, Zhening; Lu, Jie

    2017-11-22

    Cognitive deficits are a core feature of early schizophrenia. However, the pathological foundations underlying cognitive deficits are still unknown. The present study examined the association between gray matter density and cognitive deficits in first-episode schizophrenia. Structural magnetic resonance imaging of the brain was performed in 34 first-episode schizophrenia patients and 21 healthy controls. Patients were divided into two subgroups according to working memory task performance. The three groups were well matched for age, gender, and education, and the two patient groups were also further matched for diagnosis, duration of illness, and antipsychotic treatment. Voxel-based morphometric analysis was performed to estimate changes in gray matter density in first-episode schizophrenia patients with cognitive deficits. The relationships between gray matter density and clinical outcomes were explored. Patients with cognitive deficits were found to have reduced gray matter density in the vermis and tonsil of cerebellum compared with patients without cognitive deficits and healthy controls, decreased gray matter density in left supplementary motor area, bilateral precentral gyrus compared with patients without cognitive deficits. Classifier results showed GMD in cerebellar vermis tonsil cluster could differentiate SZ-CD from controls, left supplementary motor area cluster could differentiate SZ-CD from SZ-NCD. Gray matter density values of the cerebellar vermis cluster in patients groups were positively correlated with cognitive severity. Decreased gray matter density in the vermis and tonsil of cerebellum may underlie early psychosis and serve as a candidate biomarker for schizophrenia with cognitive deficits.

  13. In Vivo Evidence of Reduced Integrity of the Gray-White Matter Boundary in Autism Spectrum Disorder.

    Science.gov (United States)

    Andrews, Derek Sayre; Avino, Thomas A; Gudbrandsen, Maria; Daly, Eileen; Marquand, Andre; Murphy, Clodagh M; Lai, Meng-Chuan; Lombardo, Michael V; Ruigrok, Amber N V; Williams, Steven C; Bullmore, Edward T; The Mrc Aims Consortium; Suckling, John; Baron-Cohen, Simon; Craig, Michael C; Murphy, Declan G M; Ecker, Christine

    2017-02-01

    Atypical cortical organization and reduced integrity of the gray-white matter boundary have been reported by postmortem studies in individuals with autism spectrum disorder (ASD). However, there are no in vivo studies that examine these particular features of cortical organization in ASD. Hence, we used structural magnetic resonance imaging to examine differences in tissue contrast between gray and white matter in 98 adults with ASD and 98 typically developing controls, to test the hypothesis that individuals with ASD have significantly reduced tissue contrast. More specifically, we examined contrast as a percentage between gray and white matter tissue signal intensities (GWPC) sampled at the gray-white matter boundary, and across different cortical layers. We found that individuals with ASD had significantly reduced GWPC in several clusters throughout the cortex (cluster, P gray-white matter interface, which indicates a less distinct gray-white matter boundary in ASD. Our in vivo findings of reduced GWPC in ASD are therefore consistent with prior postmortem findings of a less well-defined gray-white matter boundary in ASD. Taken together, these results indicate that GWPC might be utilized as an in vivo proxy measure of atypical cortical microstructural organization in future studies. © The Author 2017. Published by Oxford University Press.

  14. Currency recognition using a smartphone: Comparison between color SIFT and gray scale SIFT algorithms

    Directory of Open Access Journals (Sweden)

    Iyad Abu Doush

    2017-10-01

    Full Text Available Banknote recognition means classifying the currency (coin and paper to the correct class. In this paper, we developed a dataset for Jordanian currency. After that we applied automatic mobile recognition system using a smartphone on the dataset using scale-invariant feature transform (SIFT algorithm. This is the first attempt, to the best of the authors knowledge, to recognize both coins and paper banknotes on a smartphone using SIFT algorithm. SIFT has been developed to be the most robust and efficient local invariant feature descriptor. Color provides significant information and important values in the object description process and matching tasks. Many objects cannot be classified correctly without their color features. We compared between two approaches colored local invariant feature descriptor (color SIFT approach and gray image local invariant feature descriptor (gray SIFT approach. The evaluation results show that the color SIFT approach outperforms the gray SIFT approach in terms of processing time and accuracy.

  15. Determining Surface Infiltration Rate of Permeable Pavements with Digital Imaging

    Directory of Open Access Journals (Sweden)

    Caterina Valeo

    2018-01-01

    Full Text Available Cell phone images of pervious pavement surfaces were used to explore relationships between surface infiltration rates (SIR measured using the ASTM C1701 standard test and using a simple falling head test. A fiber-reinforced porous asphalt surface and a highly permeable material comprised of stone, rubber and a polymer binder (Porous Pave were tested. Images taken with a high-resolution cellphone camera were acquired as JPEG files and converted to gray scale images in Matlab® for analysis. The distribution of gray levels was compared to the surface infiltration rates obtained for both pavements with attention given to the mean of the distribution. Investigation into the relationships between mean SIR and parameters determined from the gray level distribution produced in the image analysis revealed that mean SIR measured in both pavements were proportional to the inverse of the mean of the distribution. The relationships produced a coefficient of determination over 85% using both the ASTM and the falling head test in the porous asphalt surface. SIR measurements determined with the ASTM method were highly correlated with the inverse mean of the distribution of gray levels in the Porous Pave material as well, producing coefficients of determination of over 90% and Kendall’s tau-b of roughly 70% for nonparametric data.

  16. Image recovery using diffusion equation embedded neural network

    International Nuclear Information System (INIS)

    Torkamani-Azar, F.

    2001-01-01

    Artificial neural networks with their inherent parallelism have been shown to perform well in many processing applications. In this paper, a new self-organizing approach for the recovery of gray level images degraded by additive noise based on embedding the diffusion equation in a neural network (without using a priori knowledge about the image point spread function, noise or original image) is described which enhances and restores gray levels of degraded images and is for application in low-level processing. Two learning features have been proposed which would be effective in the practical implementation of such a network. The recovery procedure needs some parameter estimation such as different error goals. While the required computation is not excessive, the procedure dose not require too many iterations and convergence is very fast. In addition, through the simulation the new network showed that it has superior ability to give a better quality result with a minimum of the sum of the squared error

  17. Behavioral correlates of changes in hippocampal gray matter structure during acquisition of foreign vocabulary.

    Science.gov (United States)

    Bellander, Martin; Berggren, Rasmus; Mårtensson, Johan; Brehmer, Yvonne; Wenger, Elisabeth; Li, Tie-Qiang; Bodammer, Nils C; Shing, Yee-Lee; Werkle-Bergner, Markus; Lövdén, Martin

    2016-05-01

    Experience can affect human gray matter volume. The behavioral correlates of individual differences in such brain changes are not well understood. In a group of Swedish individuals studying Italian as a foreign language, we investigated associations among time spent studying, acquired vocabulary, baseline performance on memory tasks, and gray matter changes. As a way of studying episodic memory training, the language learning focused on acquiring foreign vocabulary and lasted for 10weeks. T1-weighted structural magnetic resonance imaging and cognitive testing were performed before and after the studies. Learning behavior was monitored via participants' use of a smartphone application dedicated to the study of vocabulary. A whole-brain analysis showed larger changes in gray matter structure of the right hippocampus in the experimental group (N=33) compared to an active control group (N=23). A first path analyses revealed that time spent studying rather than acquired knowledge significantly predicted change in gray matter structure. However, this association was not significant when adding performance on baseline memory measures into the model, instead only the participants' performance on a short-term memory task with highly similar distractors predicted the change. This measure may tap similar individual difference factors as those involved in gray matter plasticity of the hippocampus. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Regional gray matter growth, sexual dimorphism, and cerebral asymmetry in the neonatal brain.

    Science.gov (United States)

    Gilmore, John H; Lin, Weili; Prastawa, Marcel W; Looney, Christopher B; Vetsa, Y Sampath K; Knickmeyer, Rebecca C; Evans, Dianne D; Smith, J Keith; Hamer, Robert M; Lieberman, Jeffrey A; Gerig, Guido

    2007-02-07

    Although there has been recent interest in the study of childhood and adolescent brain development, very little is known about normal brain development in the first few months of life. In older children, there are regional differences in cortical gray matter development, whereas cortical gray and white matter growth after birth has not been studied to a great extent. The adult human brain is also characterized by cerebral asymmetries and sexual dimorphisms, although very little is known about how these asymmetries and dimorphisms develop. We used magnetic resonance imaging and an automatic segmentation methodology to study brain structure in 74 neonates in the first few weeks after birth. We found robust cortical gray matter growth compared with white matter growth, with occipital regions growing much faster than prefrontal regions. Sexual dimorphism is present at birth, with males having larger total brain cortical gray and white matter volumes than females. In contrast to adults and older children, the left hemisphere is larger than the right hemisphere, and the normal pattern of fronto-occipital asymmetry described in older children and adults is not present. Regional differences in cortical gray matter growth are likely related to differential maturation of sensory and motor systems compared with prefrontal executive function after birth. These findings also indicate that whereas some adult patterns of sexual dimorphism and cerebral asymmetries are present at birth, others develop after birth.

  19. Attention and Regional Gray Matter Development in Very Preterm Children at Age 12 Years.

    Science.gov (United States)

    Lean, Rachel E; Melzer, Tracy R; Bora, Samudragupta; Watts, Richard; Woodward, Lianne J

    2017-08-01

    This study examines the selective, sustained, and executive attention abilities of very preterm (VPT) born children in relation to concurrent structural magnetic resonance imaging (MRI) measures of regional gray matter development at age 12 years. A regional cohort of 110 VPT (≤32 weeks gestation) and 113 full term (FT) born children were assessed at corrected age 12 years on the Test of Everyday Attention-Children. They also had a structural MRI scan that was subsequently analyzed using voxel-based morphometry to quantify regional between-group differences in cerebral gray matter development, which were then related to attention measures using multivariate methods. VPT children obtained similar selective (p=.85), but poorer sustained (p=.02) and executive attention (p=.01) scores than FT children. VPT children were also characterized by reduced gray matter in the bilateral parietal, temporal, prefrontal and posterior cingulate cortices, bilateral thalami, and left hippocampus; and increased gray matter in the occipital and anterior cingulate cortices (family-wise error-corrected pregional gray matter development appear to contribute, at least in part, to the poorer attentional performance of VPT children at school age. (JINS, 2017, 23, 539-550).

  20. 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.

  1. County-Level Population Economic Status and Medicare Imaging Resource Consumption.

    Science.gov (United States)

    Rosenkrantz, Andrew B; Hughes, Danny R; Prabhakar, Anand M; Duszak, Richard

    2017-06-01

    The aim of this study was to assess relationships between county-level variation in Medicare beneficiary imaging resource consumption and measures of population economic status. The 2013 CMS Geographic Variation Public Use File was used to identify county-level per capita Medicare fee-for-service imaging utilization and nationally standardized costs to the Medicare program. The County Health Rankings public data set was used to identify county-level measures of population economic status. Regional variation was assessed, and multivariate regressions were performed. Imaging events per 1,000 Medicare beneficiaries varied 1.8-fold (range, 2,723-4,843) at the state level and 5.3-fold (range, 1,228-6,455) at the county level. Per capita nationally standardized imaging costs to Medicare varied 4.2-fold (range, $84-$353) at the state level and 14.1-fold (range, $33-$471) at the county level. Within individual states, county-level utilization varied on average 2.0-fold (range, 1.1- to 3.1-fold), and costs varied 2.8-fold (range, 1.1- to 6.4-fold). For both large urban populations and small rural states, Medicare imaging resource consumption was heterogeneously variable at the county level. Adjusting for county-level gender, ethnicity, rural status, and population density, countywide unemployment rates showed strong independent positive associations with Medicare imaging events (β = 26.96) and costs (β = 4.37), whereas uninsured rates showed strong independent positive associations with Medicare imaging costs (β = 2.68). Medicare imaging utilization and costs both vary far more at the county than at the state level. Unfavorable measures of county-level population economic status in the non-Medicare population are independently associated with greater Medicare imaging resource consumption. Future efforts to optimize Medicare imaging use should consider the influence of local indigenous socioeconomic factors outside the scope of traditional beneficiary-focused policy

  2. Premature graying of hair: An independent risk marker for coronary ...

    African Journals Online (AJOL)

    The presence of premature graying of hair was associated with 3.24 times the risk of CAD on multiple logistic regression analysis. CONCLUSION: The presence of premature graying of hair was associated with an increased risk of CAD in young smokers. Premature graying of hair can be used as preliminary evidence by ...

  3. Análise dos níveis de cinza de 4 resinas compostas micro-híbridas utilizando um sistema de radiografia digital direto =Analisys of the gray scale levels for 4 micro-hibrids composite resins using a radiograph direct digital system

    Directory of Open Access Journals (Sweden)

    Pereira, Ary Salazar Rubim et al.

    2005-01-01

    Full Text Available O objetivo deste estudo foi analisar os diferentes níveis de cinza de quatro resinas compostas micro-híbridas, através do sistema de radiografia digital direto Sens-a-Ray. As resinas utilizadas foram: Concept (Vigodent, Herculite (Sybron/Kerr, IntenS (Ivoclar Vivadent e Z 100 (3MESPE, na cor A2. Foram confeccionadas 3 placas de acrílico para cada espessura 2, 3 e 4 mm que possuíam dimensões de um filme periapical. Em todas as placas foram feitos quatro orifícios eqüidistantes com 4 mm de diâmetro onde as resinas compostas foram inseridas, esses orifícios apresentavam 4mm de diâmetro. As amostras foram radiografadas a 30 cm de distância foco-filme do sistema Sens-a-Ray por 0,8 segundo com aparelho de Raios-X (Dabi Atlante de 70 kV e 10 mA. A quantidade dos níveis de cinza, das resinas, foi aferida em pixels pelo sistema Sens-a-Ray. Foram obtidas as seguintes médias: Concept – 2 mm com 79,6; 3 mm com 85,4 e 4 mm com 96,7; Herculite – 2 mm com 65,1; 3 mm com 72,5 e 4 mm com 85,4; IntenS – 2 mm com 138,5; 3 mm com 147,3 e 4 mm com 153,7; Z 100 – 2 mm com 133,5; 3 mm com 143,8 e 4 mm com 150,6. Após os resultados foram submetidos ao teste estatístico ANOVA-Tukey com um nível de significância (p 0,05. A colorimetria foi utilizada para ilustrar a densidade óptica dos compósitos, com cores vermelho, verde e azul, representando, respectivamente do mais radiopaco para o menos radiopaco. Podemos concluir que na medida em que aumentou a espessura das placas os níveis de cinza também aumentaram. A resina Herculite apresentou os menores níveis de cinza, diferindo estatisticamente das demais. As resinas IntenS e Z 100 apresentaram maiores níveis de cinza que as demais. The aim of this study was analysed the different gray scale levels for 4 micro-hybrids composite resins, throught the direct digital radiography device, Sens-a-Ray. The composites used in this study were: Concept (Vigodent, Herculite (Sybron/Kerr, IntenS (Ivoclar

  4. Synergistic Instance-Level Subspace Alignment for Fine-Grained Sketch-Based Image Retrieval.

    Science.gov (United States)

    Li, Ke; Pang, Kaiyue; Song, Yi-Zhe; Hospedales, Timothy M; Xiang, Tao; Zhang, Honggang

    2017-08-25

    We study the problem of fine-grained sketch-based image retrieval. By performing instance-level (rather than category-level) retrieval, it embodies a timely and practical application, particularly with the ubiquitous availability of touchscreens. Three factors contribute to the challenging nature of the problem: (i) free-hand sketches are inherently abstract and iconic, making visual comparisons with photos difficult, (ii) sketches and photos are in two different visual domains, i.e. black and white lines vs. color pixels, and (iii) fine-grained distinctions are especially challenging when executed across domain and abstraction-level. To address these challenges, we propose to bridge the image-sketch gap both at the high-level via parts and attributes, as well as at the low-level, via introducing a new domain alignment method. More specifically, (i) we contribute a dataset with 304 photos and 912 sketches, where each sketch and image is annotated with its semantic parts and associated part-level attributes. With the help of this dataset, we investigate (ii) how strongly-supervised deformable part-based models can be learned that subsequently enable automatic detection of part-level attributes, and provide pose-aligned sketch-image comparisons. To reduce the sketch-image gap when comparing low-level features, we also (iii) propose a novel method for instance-level domain-alignment, that exploits both subspace and instance-level cues to better align the domains. Finally (iv) these are combined in a matching framework integrating aligned low-level features, mid-level geometric structure and high-level semantic attributes. Extensive experiments conducted on our new dataset demonstrate effectiveness of the proposed method.

  5. A Variational Level Set Model Combined with FCMS for Image Clustering Segmentation

    Directory of Open Access Journals (Sweden)

    Liming Tang

    2014-01-01

    Full Text Available The fuzzy C means clustering algorithm with spatial constraint (FCMS is effective for image segmentation. However, it lacks essential smoothing constraints to the cluster boundaries and enough robustness to the noise. Samson et al. proposed a variational level set model for image clustering segmentation, which can get the smooth cluster boundaries and closed cluster regions due to the use of level set scheme. However it is very sensitive to the noise since it is actually a hard C means clustering model. In this paper, based on Samson’s work, we propose a new variational level set model combined with FCMS for image clustering segmentation. Compared with FCMS clustering, the proposed model can get smooth cluster boundaries and closed cluster regions due to the use of level set scheme. In addition, a block-based energy is incorporated into the energy functional, which enables the proposed model to be more robust to the noise than FCMS clustering and Samson’s model. Some experiments on the synthetic and real images are performed to assess the performance of the proposed model. Compared with some classical image segmentation models, the proposed model has a better performance for the images contaminated by different noise levels.

  6. In vivo magnetic resonance spectroscopy measurement of gray-matter and white-matter gamma-aminobutyric acid concentration in sensorimotor cortex using a motion-controlled MEGA point-resolved spectroscopy sequence.

    Science.gov (United States)

    Bhattacharyya, Pallab K; Phillips, Micheal D; Stone, Lael A; Lowe, Mark J

    2011-04-01

    Gamma-aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the brain. Understanding the GABA concentration, in vivo, is important to understand normal brain function. Using MEGA point-resolved spectroscopy sequence with interleaved water scans to detect subject motion, GABA level of sensorimotor cortex was measured using a voxel identified from a functional magnetic resonance imaging scan. The GABA level in a 20×20×20-mm(3) voxel consisting of 37%±7% gray matter, 52%±12% white matter and 11%±8% cerebrospinal fluid in the sensorimotor region was measured to be 1.43±0.48 mM. In addition, using linear regression analysis, GABA concentrations within gray and white matter were calculated to be 2.87±0.61 and 0.33±0.11 mM, respectively. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. A study of trabecular bone strength and morphometric analysis of bone microstructure from digital radiographic image

    International Nuclear Information System (INIS)

    Han, Seung Yun; Lee, Sun Bok; Oh, Sung Ook; Heo, Min Suk; Lee, Sam Sun; Choi, Soon Chul; Park, Tae Won; Kim, Jong Dae

    2003-01-01

    To evaluate the relationship between morphometric analysis of microstructure from digital radiographic image and trabecular bone strength. One hundred eleven bone specimens with 5 mm thickness were obtained from the mandibles of 5 pigs. Digital images of specimens were taken using a direct digital intraoral radiographic system. After selection of ROI(100 x 100 pixel) within the trabecular bone, mean gray level and standard deviation were obtained. Fractal dimension and the variants of morphometric analysis (trabecular area, periphery, length of skeletonized trabeculae, number of terminal point, number of branch point) were obtained from ROI. Punch sheer strength analysis was performed using Instron (model 4465, Instron Corp., USA). The loading force (loading speed 1mm/min) was applied to ROI of bone specimen by a 2 mm diameter punch. Stress-deformation curve was obtained from the punch sheer strength analysis and maximum stress, yield stress, Young's modulus were measured. Maximum stress had a negative linear correlation with mean gray level and fractal dimension significantly (p<0.05). Yield stress had a negative linear correlation with mean gray level, periphery, fractal dimension and the length of skeletonized trabeculae significantly (p<0.05). Young's modulus had a negative linear correlation with mean gray level and fractal dimension significantly (p<0.05). The strength of cancellous bone exhibited a significantly linear relationship between mean gray level, fractal dimension and morphometric analysis. The methods described above can be easily used to evaluate bone quality clinically.

  8. Delamination wear mechanism in gray cast irons

    International Nuclear Information System (INIS)

    Salehi, M.

    2000-01-01

    An investigation of the friction and sliding wear of gray cast iron against chromium plated cast irons was carried out on a newly constructed reciprocating friction and wear tester. The tests were the first to be done on the test rig under dry conditions and at the speed of 170 cm/min, and variable loads of 20-260 N for a duration of 15 min. to 3 hours. The gray cast iron surfaces worn by a process of plastic deformation at the subsurface, crack nucleation, and crack growth leading to formation of plate like debris and therefore the delamination theory applies. No evidence of adhesion was observed. This could be due to formation of oxides on the wear surface which prevent adhesion. channel type chromium plating ''picked'' up cast iron from the counter-body surfaces by mechanically trapping cast iron debris on and within the cracks. The removal of the plated chromium left a pitted surface on the cast iron

  9. Gray divorce: Explaining midlife marital splits.

    Science.gov (United States)

    Crowley, Jocelyn Elise

    2017-12-06

    Recent research suggests that one out of every four divorces in the United States is now "gray," meaning that at least one half of the couple has reached the age of 50 when the marriage breaks down. To understand why this age group-the Baby Boomer generation-is splitting up, this study conducted 40 in-depth, semistructured interviews with men and 40 with women who have experienced a gray divorce in their lifetimes. Respondents' beliefs in an expressive individualistic model of marriage, where partnerships are only valuable if they help individuals achieve personal growth, were compared against their potential adherence to what I call a commitment-based model of marriage, where binding, romantic love holds couples together unless there is severe relationship strain. The results demonstrated that the commitment-based model most strongly governs marriage and the decision to divorce among Baby Boomers for both sexes, although some specific reasons for divorce differ for men and women.

  10. 3D change detection at street level using mobile laser scanning point clouds and terrestrial images

    Science.gov (United States)

    Qin, Rongjun; Gruen, Armin

    2014-04-01

    Automatic change detection and geo-database updating in the urban environment are difficult tasks. There has been much research on detecting changes with satellite and aerial images, but studies have rarely been performed at the street level, which is complex in its 3D geometry. Contemporary geo-databases include 3D street-level objects, which demand frequent data updating. Terrestrial images provides rich texture information for change detection, but the change detection with terrestrial images from different epochs sometimes faces problems with illumination changes, perspective distortions and unreliable 3D geometry caused by the lack of performance of automatic image matchers, while mobile laser scanning (MLS) data acquired from different epochs provides accurate 3D geometry for change detection, but is very expensive for periodical acquisition. This paper proposes a new method for change detection at street level by using combination of MLS point clouds and terrestrial images: the accurate but expensive MLS data acquired from an early epoch serves as the reference, and terrestrial images or photogrammetric images captured from an image-based mobile mapping system (MMS) at a later epoch are used to detect the geometrical changes between different epochs. The method will automatically mark the possible changes in each view, which provides a cost-efficient method for frequent data updating. The methodology is divided into several steps. In the first step, the point clouds are recorded by the MLS system and processed, with data cleaned and classified by semi-automatic means. In the second step, terrestrial images or mobile mapping images at a later epoch are taken and registered to the point cloud, and then point clouds are projected on each image by a weighted window based z-buffering method for view dependent 2D triangulation. In the next step, stereo pairs of the terrestrial images are rectified and re-projected between each other to check the geometrical

  11. A color fusion method of infrared and low-light-level images based on visual perception

    Science.gov (United States)

    Han, Jing; Yan, Minmin; Zhang, Yi; Bai, Lianfa

    2014-11-01

    The color fusion images can be obtained through the fusion of infrared and low-light-level images, which will contain both the information of the two. The fusion images can help observers to understand the multichannel images comprehensively. However, simple fusion may lose the target information due to inconspicuous targets in long-distance infrared and low-light-level images; and if targets extraction is adopted blindly, the perception of the scene information will be affected seriously. To solve this problem, a new fusion method based on visual perception is proposed in this paper. The extraction of the visual targets ("what" information) and parallel processing mechanism are applied in traditional color fusion methods. The infrared and low-light-level color fusion images are achieved based on efficient typical targets learning. Experimental results show the effectiveness of the proposed method. The fusion images achieved by our algorithm can not only improve the detection rate of targets, but also get rich natural information of the scenes.

  12. Combining low level features and visual attributes for VHR remote sensing image classification

    Science.gov (United States)

    Zhao, Fumin; Sun, Hao; Liu, Shuai; Zhou, Shilin

    2015-12-01

    Semantic classification of very high resolution (VHR) remote sensing images is of great importance for land use or land cover investigation. A large number of approaches exploiting different kinds of low level feature have been proposed in the literature. Engineers are often frustrated by their conclusions and a systematic assessment of various low level features for VHR remote sensing image classification is needed. In this work, we firstly perform an extensive evaluation of eight features including HOG, dense SIFT, SSIM, GIST, Geo color, LBP, Texton and Tiny images for classification of three public available datasets. Secondly, we propose to transfer ground level scene attributes to remote sensing images. Thirdly, we combine both low-level features and mid-level visual attributes to further improve the classification performance. Experimental results demonstrate that i) Dene SIFT and HOG features are more robust than other features for VHR scene image description. ii) Visual attribute competes with a combination of low level features. iii) Multiple feature combination achieves the best performance under different settings.

  13. Grays River Watershed and Biological Assessment Final Report 2006.

    Energy Technology Data Exchange (ETDEWEB)

    May, Christopher W.; McGrath, Kathleen E.; Geist, David R. [Pacific Northwest National Laboratory; Abbe, Timothy; Barton, Chase [Herrera Environmental Consultants, Inc.

    2008-02-04

    habitat conditions, and biological integrity. In addition, human land-use impacts are factored into the conceptual model because they can alter habitat quality and can disrupt natural habitat-forming processes. In this model (Figure S.1), aquatic habitat--both instream and riparian--is viewed as the link between watershed conditions and biologic responses. Based on this conceptual model, assessment of habitat loss and the resultant declines in salmonid populations can be conducted by relating current and historical (e.g., natural) habitat conditions to salmonid utilization, diversity, and abundance. In addition, assessing disrupted ecosystem functions and processes within the watershed can aid in identifying the causes of habitat change and the associated decline in biological integrity. In this same way, restoration, enhancement, and conservation projects can be identified and prioritized. A watershed assessment is primarily a landscape-scale evaluation of current watershed conditions and the associated hydrogeomorphic riverine processes. The watershed assessment conducted for this project focused on watershed processes that form and maintain salmonid habitat. Landscape metrics describing the level of human alteration of natural ecosystem attributes were used as indicators of water quality, hydrology, channel geomorphology, instream habitat, and biotic integrity. Ecological (watershed) processes are related to and can be predicted based on specific aspects of spatial pattern. This study evaluated the hydrologic regime, sediment delivery regime, and riparian condition of the sub-watersheds that comprise the upper Grays River watershed relative to their natural range of conditions. Analyses relied primarily on available geographic information system (GIS) data describing landscape characteristics such as climate, vegetation type and maturity, geology and soils, topography, land use, and road density. In addition to watershed-scale landscape characteristics, the study area

  14. Grays River Watershed and Biological Assessment, 2006 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    May, Christopher; Geist, David [Pacific Northwest National Laboratory

    2007-04-01

    habitat conditions, and biological integrity. In addition, human land-use impacts are factored into the conceptual model because they can alter habitat quality and can disrupt natural habitat forming processes. In this model (Figure S.1), aquatic habitat--both instream and riparian--is viewed as the link between watershed conditions and biologic responses. Based on this conceptual model, assessment of habitat loss and the resultant declines in salmonid populations can be conducted by relating current and historical (e.g., natural) habitat conditions to salmonid utilization, diversity, and abundance. In addition, assessing disrupted ecosystem functions and processes within the watershed can aid in identifying the causes of habitat change and the associated decline in biological integrity. In this same way, restoration, enhancement, and conservation projects can be identified and prioritized. A watershed assessment is primarily a landscape-scale evaluation of current watershed conditions and the associated hydrogeomorphic riverine processes. The watershed assessment conducted for this project focused on watershed processes that form and maintain salmonid habitat. Landscape metrics describing the level of human alteration of natural ecosystem attributes were used as indicators of water quality, hydrology, channel geomorphology, instream habitat, and biotic integrity. Ecological (watershed) processes are related to and can be predicted based on specific aspects of spatial pattern. This study evaluated the hydrologic regime, sediment delivery regime, and riparian condition of the sub-watersheds that comprise the upper Grays River watershed relative to their natural range of conditions. Analyses relied primarily on available geographic information system (GIS) data describing landscape characteristics such as climate, vegetation type and maturity, geology and soils, topography, land use, and road density. In addition to watershed-scale landscape characteristics, the study area

  15. Regional gray matter correlates of vocational interests.

    Science.gov (United States)

    Schroeder, David H; Haier, Richard J; Tang, Cheuk Ying

    2012-05-16

    Previous studies have identified brain areas related to cognitive abilities and personality, respectively. In this exploratory study, we extend the application of modern neuroimaging techniques to another area of individual differences, vocational interests, and relate the results to an earlier study of cognitive abilities salient for vocations. First, we examined the psychometric relationships between vocational interests and abilities in a large sample. The primary relationships between those domains were between Investigative (scientific) interests and general intelligence and between Realistic ("blue-collar") interests and spatial ability. Then, using MRI and voxel-based morphometry, we investigated the relationships between regional gray matter volume and vocational interests. Specific clusters of gray matter were found to be correlated with Investigative and Realistic interests. Overlap analyses indicated some common brain areas between the correlates of Investigative interests and general intelligence and between the correlates of Realistic interests and spatial ability. Two of six vocational-interest scales show substantial relationships with regional gray matter volume. The overlap between the brain correlates of these scales and cognitive-ability factors suggest there are relationships between individual differences in brain structure and vocations.

  16. Gray rod for a nuclear reactor

    International Nuclear Information System (INIS)

    Francis, T.A.; Cerni, Samuel.

    1986-01-01

    The invention relates to an improved gray rod for insertion in a nuclear fuel assembly having an array of fuel rods. The gray rod includes a thin-walled cladding tube a first longitudinal section of which is positioned within, and a second longitudinal section of which is positioned essentially without, the array of fuel rods when the gray rod is inserted in the fuel assembly. The first longitudinal section defines a pellet-receiving space having detained therein a stack of annular pellets with an outer diameter sufficient to lend radial support to the wall of the first longitudinal tube section. The second longitudinal section defines a hollow space devoid of pellets and having means to resist radial collapse under external pressure. This means may be a partially compressed spiral spring which serves the dual purpose of retaining the stack of pellets in the pellet-receiving space and of lending radial support to the wall of the second longitudinal tube section or it may be holes through the wall to allow pressure equalisation. The cladding tube is composed of stainless-steel material having a low neutron-capture cross-section, and the annular pellets preferably being composed of Zircaloy or Zirconia material. (author)

  17. Tile-Level Annotation of Satellite Images Using Multi-Level Max-Margin Discriminative Random Field

    Directory of Open Access Journals (Sweden)

    Hong Sun

    2013-05-01

    Full Text Available This paper proposes a multi-level max-margin discriminative analysis (M3DA framework, which takes both coarse and fine semantics into consideration, for the annotation of high-resolution satellite images. In order to generate more discriminative topic-level features, the M3DA uses the maximum entropy discrimination latent Dirichlet Allocation (MedLDA model. Moreover, for improving the spatial coherence of visual words neglected by M3DA, conditional random field (CRF is employed to optimize the soft label field composed of multiple label posteriors. The framework of M3DA enables one to combine word-level features (generated by support vector machines and topic-level features (generated by MedLDA via the bag-of-words representation. The experimental results on high-resolution satellite images have demonstrated that, using the proposed method can not only obtain suitable semantic interpretation, but also improve the annotation performance by taking into account the multi-level semantics and the contextual information.

  18. Optimized VBM in patients with Alzheimer's disease: gray matter loss and its correlation with cognitive function

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Seon Hyeong; Moon, Won Jin; Chung, Eun Chul; Lee, Min Hee; Roh, Hong Gee; Park, Kwang Bo; Na, Duck Ryul [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2005-11-15

    To investigate the regional changes in gray matter volume by using optimized voxel based morphometry in the whole brain of patients with Alzheimer's disease (AD) and to determine its correlation with cognitive function. Nineteen patients with AD (mean mini mental state examination (MMSE) score = 20.4) and 19 age-matched control subjects (mean MMSE score 29) participated in this prospective study. T1-weighted 3D-SPGR scans were obtained for each subject. These T1-weighted images were spatially normalized into study-specific T1 template and segmented into gray matter, white matter and CSF. After the images were modulated and smoothed, all of the gray matter images were compared with control images by using voxel-wise statistical parametric test (two-sample-test). In patients with AD, total gray matter volume was significantly smaller than normal control (552 {+-} 39 mL vs. 632 {+-} 51 mL, {rho} 0.001). Significant gray matter loss was seen in both the hippocampus and amygdala complexs, and the parahippocampi and frontoparietal cortices ({rho} < 0.01, family wise error corrected). Left cerebral atrophy was more prominent than the right. Loss of gray matter volume in both the superior frontal gyri and left inferior temporal gyrus had a strong correlation with lower MMSE score. Optimized VBM was able to visualize pathologic changes of AD in vivo. In AD there was widespread gray matter volume loss in the frontoparietal lobes as well as the medial temporal lobes and had a strong correlation between volume loss of specific cortical areas and MMSE score.

  19. Parcellation of the human orbitofrontal cortex based on gray matter volume covariance.

    Science.gov (United States)

    Liu, Huaigui; Qin, Wen; Qi, Haotian; Jiang, Tianzi; Yu, Chunshui

    2015-02-01

    The human orbitofrontal cortex (OFC) is an enigmatic brain region that cannot be parcellated reliably using diffusional and functional magnetic resonance imaging (fMRI) because there is signal dropout that results from an inherent defect in imaging techniques. We hypothesise that the OFC can be reliably parcellated into subregions based on gray matter volume (GMV) covariance patterns that are derived from artefact-free structural images. A total of 321 healthy young subjects were examined by high-resolution structural MRI. The OFC was parcellated into subregions-based GMV covariance patterns; and then sex and laterality differences in GMV covariance pattern of each OFC subregion were compared. The human OFC was parcellated into the anterior (OFCa), medial (OFCm), posterior (OFCp), intermediate (OFCi), and lateral (OFCl) subregions. This parcellation scheme was validated by the same analyses of the left OFC and the bilateral OFCs in male and female subjects. Both visual observation and quantitative comparisons indicated a unique GMV covariance pattern for each OFC subregion. These OFC subregions mainly covaried with the prefrontal and temporal cortices, cingulate cortex and amygdala. In addition, GMV correlations of most OFC subregions were similar across sex and laterality except for significant laterality difference in the OFCl. The right OFCl had stronger GMV correlation with the right inferior frontal cortex. Using high-resolution structural images, we established a reliable parcellation scheme for the human OFC, which may provide an in vivo guide for subregion-level studies of this region and improve our understanding of the human OFC at subregional levels. © 2014 Wiley Periodicals, Inc.

  20. Level-set-based reconstruction algorithm for EIT lung images: first clinical results.

    Science.gov (United States)

    Rahmati, Peyman; Soleimani, Manuchehr; Pulletz, Sven; Frerichs, Inéz; Adler, Andy

    2012-05-01

    We show the first clinical results using the level-set-based reconstruction algorithm for electrical impedance tomography (EIT) data. The level-set-based reconstruction method (LSRM) allows the reconstruction of non-smooth interfaces between image regions, which are typically smoothed by traditional voxel-based reconstruction methods (VBRMs). We develop a time difference formulation of the LSRM for 2D images. The proposed reconstruction method is applied to reconstruct clinical EIT data of a slow flow inflation pressure-volume manoeuvre in lung-healthy and adult lung-injury patients. Images from the LSRM and the VBRM are compared. The results show comparable reconstructed images, but with an improved ability to reconstruct sharp conductivity changes in the distribution of lung ventilation using the LSRM.

  1. Level-set-based reconstruction algorithm for EIT lung images: first clinical results

    International Nuclear Information System (INIS)

    Rahmati, Peyman; Adler, Andy; Soleimani, Manuchehr; Pulletz, Sven; Frerichs, Inéz

    2012-01-01

    We show the first clinical results using the level-set-based reconstruction algorithm for electrical impedance tomography (EIT) data. The level-set-based reconstruction method (LSRM) allows the reconstruction of non-smooth interfaces between image regions, which are typically smoothed by traditional voxel-based reconstruction methods (VBRMs). We develop a time difference formulation of the LSRM for 2D images. The proposed reconstruction method is applied to reconstruct clinical EIT data of a slow flow inflation pressure–volume manoeuvre in lung-healthy and adult lung-injury patients. Images from the LSRM and the VBRM are compared. The results show comparable reconstructed images, but with an improved ability to reconstruct sharp conductivity changes in the distribution of lung ventilation using the LSRM. (paper)

  2. Image processing and recognition for biological images.

    Science.gov (United States)

    Uchida, Seiichi

    2013-05-01

    This paper reviews image processing and pattern recognition techniques, which will be useful to analyze bioimages. Although this paper does not provide their technical details, it will be possible to grasp their main tasks and typical tools to handle the tasks. Image processing is a large research area to improve the visibility of an input image and acquire some valuable information from it. As the main tasks of image processing, this paper introduces gray-level transformation, binarization, image filtering, image segmentation, visual object tracking, optical flow and image registration. Image pattern recognition is the technique to classify an input image into one of the predefined classes and also has a large research area. This paper overviews its two main modules, that is, feature extraction module and classification module. Throughout the paper, it will be emphasized that bioimage is a very difficult target for even state-of-the-art image processing and pattern recognition techniques due to noises, deformations, etc. This paper is expected to be one tutorial guide to bridge biology and image processing researchers for their further collaboration to tackle such a difficult target. © 2013 The Author Development, Growth & Differentiation © 2013 Japanese Society of Developmental Biologists.

  3. Research on Remote Sensing Image Classification Based on Feature Level Fusion

    Science.gov (United States)

    Yuan, L.; Zhu, G.

    2018-04-01

    Remote sensing image classification, as an important direction of remote sensing image processing and application, has been widely studied. However, in the process of existing classification algorithms, there still exists the phenomenon of misclassification and missing points, which leads to the final classification accuracy is not high. In this paper, we selected Sentinel-1A and Landsat8 OLI images as data sources, and propose a classification method based on feature level fusion. Compare three kind of feature level fusion algorithms (i.e., Gram-Schmidt spectral sharpening, Principal Component Analysis transform and Brovey transform), and then select the best fused image for the classification experimental. In the classification process, we choose four kinds of image classification algorithms (i.e. Minimum distance, Mahalanobis distance, Support Vector Machine and ISODATA) to do contrast experiment. We use overall classification precision and Kappa coefficient as the classification accuracy evaluation criteria, and the four classification results of fused image are analysed. The experimental results show that the fusion effect of Gram-Schmidt spectral sharpening is better than other methods. In four kinds of classification algorithms, the fused image has the best applicability to Support Vector Machine classification, the overall classification precision is 94.01 % and the Kappa coefficients is 0.91. The fused image with Sentinel-1A and Landsat8 OLI is not only have more spatial information and spectral texture characteristics, but also enhances the distinguishing features of the images. The proposed method is beneficial to improve the accuracy and stability of remote sensing image classification.

  4. Analysis of gene expression levels in individual bacterial cells without image segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, In Hae; Son, Minjun [Physics Department, University of Florida, P.O. Box 118440, Gainesville, FL 32611-8440 (United States); Hagen, Stephen J., E-mail: sjhagen@ufl.edu [Physics Department, University of Florida, P.O. Box 118440, Gainesville, FL 32611-8440 (United States)

    2012-05-11

    Highlights: Black-Right-Pointing-Pointer We present a method for extracting gene expression data from images of bacterial cells. Black-Right-Pointing-Pointer The method does not employ cell segmentation and does not require high magnification. Black-Right-Pointing-Pointer Fluorescence and phase contrast images of the cells are correlated through the physics of phase contrast. Black-Right-Pointing-Pointer We demonstrate the method by characterizing noisy expression of comX in Streptococcus mutans. -- Abstract: Studies of stochasticity in gene expression typically make use of fluorescent protein reporters, which permit the measurement of expression levels within individual cells by fluorescence microscopy. Analysis of such microscopy images is almost invariably based on a segmentation algorithm, where the image of a cell or cluster is analyzed mathematically to delineate individual cell boundaries. However segmentation can be ineffective for studying bacterial cells or clusters, especially at lower magnification, where outlines of individual cells are poorly resolved. Here we demonstrate an alternative method for analyzing such images without segmentation. The method employs a comparison between the pixel brightness in phase contrast vs fluorescence microscopy images. By fitting the correlation between phase contrast and fluorescence intensity to a physical model, we obtain well-defined estimates for the different levels of gene expression that are present in the cell or cluster. The method reveals the boundaries of the individual cells, even if the source images lack the resolution to show these boundaries clearly.

  5. Analysis of gene expression levels in individual bacterial cells without image segmentation

    International Nuclear Information System (INIS)

    Kwak, In Hae; Son, Minjun; Hagen, Stephen J.

    2012-01-01

    Highlights: ► We present a method for extracting gene expression data from images of bacterial cells. ► The method does not employ cell segmentation and does not require high magnification. ► Fluorescence and phase contrast images of the cells are correlated through the physics of phase contrast. ► We demonstrate the method by characterizing noisy expression of comX in Streptococcus mutans. -- Abstract: Studies of stochasticity in gene expression typically make use of fluorescent protein reporters, which permit the measurement of expression levels within individual cells by fluorescence microscopy. Analysis of such microscopy images is almost invariably based on a segmentation algorithm, where the image of a cell or cluster is analyzed mathematically to delineate individual cell boundaries. However segmentation can be ineffective for studying bacterial cells or clusters, especially at lower magnification, where outlines of individual cells are poorly resolved. Here we demonstrate an alternative method for analyzing such images without segmentation. The method employs a comparison between the pixel brightness in phase contrast vs fluorescence microscopy images. By fitting the correlation between phase contrast and fluorescence intensity to a physical model, we obtain well-defined estimates for the different levels of gene expression that are present in the cell or cluster. The method reveals the boundaries of the individual cells, even if the source images lack the resolution to show these boundaries clearly.

  6. Storage phosphor radiography of wrist fractures: a subjective comparison of image quality at varying exposure levels

    Energy Technology Data Exchange (ETDEWEB)

    Peer, Regina; Giacomuzzi, Salvatore M.; Bodner, Gerd; Jaschke, Werner; Peer, Siegfried [Innsbruck Univ. (Austria). Inst. fuer Radiologie; Lanser, Anton [Academy of Radiology Technicians, Innsbruck (Austria); Pechlaner, Sigurd [Department of Traumatology, University Hospital, Innsbruck (Austria); Kuenzel, Karl Heinz; Gaber, O. [Department of Anatomy and Histology, University Hospital, Innsbruck (Austria)

    2002-06-01

    Image quality of storage phosphor radiographs acquired at different exposure levels was compared to define the minimal radiation dose needed to achieve images which allow for reliable detection of wrist fractures. In a study on 33 fractured anatomical wrist specimens image quality of storage phosphor radiographs was assessed on a diagnostic PACS workstation by three observers. Images were acquired at exposure levels corresponding to a speed classes 100, 200, 400 and 800. Cortical bone surface, trabecular bone, soft tissues and fracture delineation were judged on a subjective basis. Image quality was rated according to a standard protocol and statistical evaluation was performed based on an analysis of variance (ANOVA). Images at a dose reduction of 37% were rated sufficient quality without loss in diagnostic accuracy. Sufficient trabecular and cortical bone presentation was still achieved at a dose reduction of 62%. The latter images, however, were considered unacceptable for fracture detection. To achieve high-quality storage phosphor radiographs, which allow for a reliable evaluation of wrist fractures, a minimum exposure dose equivalent to a speed class of 200 is needed. For general-purpose skeletal radiography, however, a dose reduction of up to 62% can be achieved. A choice of exposure settings according to the clinical situation (ALARA principle) is recommended to achieve possible dose reductions. (orig.)

  7. Gray and white matter distribution in dyslexia: a VBM study of superior temporal gyrus asymmetry.

    Directory of Open Access Journals (Sweden)

    Marjorie Dole

    Full Text Available In the present study, we investigated brain morphological signatures of dyslexia by using a voxel-based asymmetry analysis. Dyslexia is a developmental disorder that affects the acquisition of reading and spelling abilities and is associated with a phonological deficit. Speech perception disabilities have been associated with this deficit, particularly when listening conditions are challenging, such as in noisy environments. These deficits are associated with known neurophysiological correlates, such as a reduction in the functional activation or a modification of functional asymmetry in the cortical regions involved in speech processing, such as the bilateral superior temporal areas. These functional deficits have been associated with macroscopic morphological abnormalities, which potentially include a reduction in gray and white matter volumes, combined with modifications of the leftward asymmetry along the perisylvian areas. The purpose of this study was to investigate gray/white matter distribution asymmetries in dyslexic adults using automated image processing derived from the voxel-based morphometry technique. Correlations with speech-in-noise perception abilities were also investigated. The results confirmed the presence of gray matter distribution abnormalities in the superior temporal gyrus (STG and the superior temporal Sulcus (STS in individuals with dyslexia. Specifically, the gray matter of adults with dyslexia was symmetrically distributed over one particular region of the STS, the temporal voice area, whereas normal readers showed a clear rightward gray matter asymmetry in this area. We also identified a region in the left posterior STG in which the white matter distribution asymmetry was correlated to speech-in-noise comprehension abilities in dyslexic adults. These results provide further information concerning the morphological alterations observed in dyslexia, revealing the presence of both gray and white matter distribution

  8. Microstructural abnormalities in white and gray matter in obese adolescents with and without type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Arie Nouwen

    Full Text Available Aims/hypotheses: In adults, type 2 diabetes and obesity have been associated with structural brain changes, even in the absence of dementia. Some evidence suggested similar changes in adolescents with type 2 diabetes but comparisons with a non-obese control group have been lacking. The aim of the current study was to examine differences in microstructure of gray and white matter between adolescents with type 2 diabetes, obese adolescents and healthy weight adolescents. Methods: Magnetic resonance imaging data were collected from 15 adolescents with type 2 diabetes, 21 obese adolescents and 22 healthy weight controls. Volumetric differences in the gray matter between the three groups were examined using voxel based morphology, while tract based spatial statistics was used to examine differences in the microstructure of the white matter. Results: Adolescents with type 2 diabetes and obese adolescents had reduced gray matter volume in the right hippocampus, left putamen and caudate, bilateral amygdala and left thalamus compared to healthy weight controls. Type 2 diabetes was also associated with significant regional changes in fractional anisotropy within the corpus callosum, fornix, left inferior fronto-occipital fasciculus, left uncinate, left internal and external capsule. Fractional anisotropy reductions within these tracts were explained by increased radial diffusivity, which may suggest demyelination of white matter tracts. Mean diffusivity and axial diffusivity did not differ between the groups. Conclusion/interpretation: Our data shows that adolescent obesity alone results in reduced gray matter volume and that adolescent type 2 diabetes is associated with both white and gray matter abnormalities. Keywords: Type 2 diabetes, Obesity, White matter, Gray matter, Demyelination

  9. Breakfast staple types affect brain gray matter volume and cognitive function in healthy children.

    Directory of Open Access Journals (Sweden)

    Yasuyuki Taki

    Full Text Available Childhood diet is important for brain development. Furthermore, the quality of breakfast is thought to affect the cognitive functioning of well-nourished children. To analyze the relationship among breakfast staple type, gray matter volume, and intelligence quotient (IQ in 290 healthy children, we used magnetic resonance images and applied voxel-based morphometry. We divided subjects into rice, bread, and both groups according to their breakfast staple. We showed that the rice group had a significantly larger gray matter ratio (gray matter volume percentage divided by intracranial volume and significantly larger regional gray matter volumes of several regions, including the left superior temporal gyrus. The bread group had significantly larger regional gray and white matter volumes of several regions, including the right frontoparietal region. The perceptual organization index (POI; IQ subcomponent of the rice group was significantly higher than that of the bread group. All analyses were adjusted for age, gender, intracranial volume, socioeconomic status, average weekly frequency of having breakfast, and number of side dishes eaten for breakfast. Although several factors may have affected the results, one possible mechanism underlying the difference between the bread and the rice groups may be the difference in the glycemic index (GI of these two substances; foods with a low GI are associated with less blood-glucose fluctuation than are those with a high GI. Our study suggests that breakfast staple type affects brain gray and white matter volumes and cognitive function in healthy children; therefore, a diet of optimal nutrition is important for brain maturation during childhood and adolescence.

  10. Breakfast staple types affect brain gray matter volume and cognitive function in healthy children.

    Science.gov (United States)

    Taki, Yasuyuki; Hashizume, Hiroshi; Sassa, Yuko; Takeuchi, Hikaru; Asano, Michiko; Asano, Kohei; Kawashima, Ryuta

    2010-12-08

    Childhood diet is important for brain development. Furthermore, the quality of breakfast is thought to affect the cognitive functioning of well-nourished children. To analyze the relationship among breakfast staple type, gray matter volume, and intelligence quotient (IQ) in 290 healthy children, we used magnetic resonance images and applied voxel-based morphometry. We divided subjects into rice, bread, and both groups according to their breakfast staple. We showed that the rice group had a significantly larger gray matter ratio (gray matter volume percentage divided by intracranial volume) and significantly larger regional gray matter volumes of several regions, including the left superior temporal gyrus. The bread group had significantly larger regional gray and white matter volumes of several regions, including the right frontoparietal region. The perceptual organization index (POI; IQ subcomponent) of the rice group was significantly higher than that of the bread group. All analyses were adjusted for age, gender, intracranial volume, socioeconomic status, average weekly frequency of having breakfast, and number of side dishes eaten for breakfast. Although several factors may have affected the results, one possible mechanism underlying the difference between the bread and the rice groups may be the difference in the glycemic index (GI) of these two substances; foods with a low GI are associated with less blood-glucose fluctuation than are those with a high GI. Our study suggests that breakfast staple type affects brain gray and white matter volumes and cognitive function in healthy children; therefore, a diet of optimal nutrition is important for brain maturation during childhood and adolescence.

  11. Gray and white matter distribution in dyslexia: a VBM study of superior temporal gyrus asymmetry.

    Science.gov (United States)

    Dole, Marjorie; Meunier, Fanny; Hoen, Michel

    2013-01-01

    In the present study, we investigated brain morphological signatures of dyslexia by using a voxel-based asymmetry analysis. Dyslexia is a developmental disorder that affects the acquisition of reading and spelling abilities and is associated with a phonological deficit. Speech perception disabilities have been associated with this deficit, particularly when listening conditions are challenging, such as in noisy environments. These deficits are associated with known neurophysiological correlates, such as a reduction in the functional activation or a modification of functional asymmetry in the cortical regions involved in speech processing, such as the bilateral superior temporal areas. These functional deficits have been associated with macroscopic morphological abnormalities, which potentially include a reduction in gray and white matter volumes, combined with modifications of the leftward asymmetry along the perisylvian areas. The purpose of this study was to investigate gray/white matter distribution asymmetries in dyslexic adults using automated image processing derived from the voxel-based morphometry technique. Correlations with speech-in-noise perception abilities were also investigated. The results confirmed the presence of gray matter distribution abnormalities in the superior temporal gyrus (STG) and the superior temporal Sulcus (STS) in individuals with dyslexia. Specifically, the gray matter of adults with dyslexia was symmetrically distributed over one particular region of the STS, the temporal voice area, whereas normal readers showed a clear rightward gray matter asymmetry in this area. We also identified a region in the left posterior STG in which the white matter distribution asymmetry was correlated to speech-in-noise comprehension abilities in dyslexic adults. These results provide further information concerning the morphological alterations observed in dyslexia, revealing the presence of both gray and white matter distribution anomalies and the

  12. APPLICATION OF A LATTICE GAS MODEL FOR SUBPIXEL PROCESSING OF LOW-RESOLUTION IMAGES OF BINARY STRUCTURES

    Directory of Open Access Journals (Sweden)

    Zbisław Tabor

    2011-05-01

    Full Text Available In the study an algorithm based on a lattice gas model is proposed as a tool for enhancing quality of lowresolution images of binary structures. Analyzed low-resolution gray-level images are replaced with binary images, in which pixel size is decreased. The intensity in the pixels of these new images is determined by corresponding gray-level intensities in the original low-resolution images. Then the white phase pixels in the binary images are assumed to be particles interacting with one another, interacting with properly defined external field and allowed to diffuse. The evolution is driven towards a state with maximal energy by Metropolis algorithm. This state is used to estimate the imaged object. The performance of the proposed algorithm and local and global thresholding methods are compared.

  13. Fourier power spectrum characteristics of face photographs: attractiveness perception depends on low-level image properties.

    Science.gov (United States)

    Menzel, Claudia; Hayn-Leichsenring, Gregor U; Langner, Oliver; Wiese, Holger; Redies, Christoph

    2015-01-01

    We investigated whether low-level processed image properties that are shared by natural scenes and artworks - but not veridical face photographs - affect the perception of facial attractiveness and age. Specifically, we considered the slope of the radially averaged Fourier power spectrum in a log-log plot. This slope is a measure of the distribution of special frequency power in an image. Images of natural scenes and artworks possess - compared to face images - a relatively shallow slope (i.e., increased high spatial frequency power). Since aesthetic perception might be based on the efficient processing of images with natural scene statistics, we assumed that the perception of facial attractiveness might also be affected by these properties. We calculated Fourier slope and other beauty-associated measurements in face images and correlated them with ratings of attractiveness and age of the depicted persons (Study 1). We found that Fourier slope - in contrast to the other tested image properties - did not predict attractiveness ratings when we controlled for age. In Study 2A, we overlaid face images with random-phase patterns with different statistics. Patterns with a slope similar to those in natural scenes and artworks resulted in lower attractiveness and higher age ratings. In Studies 2B and 2C, we directly manipulated the Fourier slope of face images and found that images with shallower slopes were rated as more attractive. Additionally, attractiveness of unaltered faces was affected by the Fourier slope of a random-phase background (Study 3). Faces in front of backgrounds with statistics similar to natural scenes and faces were rated as more attractive. We conclude that facial attractiveness ratings are affected by specific image properties. An explanation might be the efficient coding hypothesis.

  14. Identifying FRBR Work-Level Data in MARC Bibliographic Records for Manifestations of Moving Images

    Directory of Open Access Journals (Sweden)

    Lynne Bisko

    2008-12-01

    Full Text Available The library metadata community is dealing with the challenge of implementing the conceptual model, Functional Requirements for Bibliographic Records (FRBR. In response, the Online Audiovisual Catalogers (OLAC created a task force to study the issues related to creating and using FRBR-based work-level records for moving images. This article presents one part of the task force's work: it looks at the feasibility of creating provisional FRBR work-level records for moving images by extracting data from existing manifestation-level bibliographic records. Using a sample of 941 MARC records, a subgroup of the task force conducted a pilot project to look at five characteristics of moving image works. Here they discuss their methodology; analysis; selected results for two elements, original date (year and director name; and conclude with some suggested changes to MARC coding and current cataloging policy.

  15. 8-oxo-7,8-dihydroguanine level - the DNA oxidative stress marker - recognized by fluorescence image analysis in sporadic uterine adenocarcinomas in women.

    Science.gov (United States)

    Postawski, Krzysztof; Przadka-Rabaniuk, Dorota; Piersiak, Tomasz

    2013-01-01

    In the case of carcinogenesis in human endometrium no information exists on tissue concentration of 8-oxo-7,8-dihydroguanine, the DNA oxidative stress marker This was the main reason to undertake the investigation of this DNA modification in human uterine estrogen-dependent tissue cancers. In order to estimate the level of oxidative damage, 8-oxo-7,8-dihydroguanine was determined directly in cells of tissue microscope slides using OxyDNA Assay Kit, Fluorometric. Cells were investigated under confocal microscope. Images of individual cells were captured by computer-interfaced digital photography and analyzed for fluorescence intensities (continuous inverted 8-bit gray-scale = 0 [black]-255 [white]). Fluorescence scores were calculated for each of 13 normal endometrial samples and 31 uterine adenocarcinoma specimens. Finally the level of the oxidative stress marker was also analyzed according to histological and clinical features of the neoplasms. The obtained data revealed that: 8-oxo-7,8-dihydroguanine levels were higher in uterine adenocarcinomas than in normal endometrial samples (48,32 vs. 38,64; p<0,001); in contrast to normal endometrium there was no correlation between age and DNA oxidative modification content in uterine cancer; highest mean fluorescence intensity was recognized in G2 endometrial adenocarcinomas; level of 8-oxo-7,8-dihydroguanine does not depend on Body Mass Index (BMI) and cancer uterine wall infiltration or tumor FIGO stage. Our study indicates that accumulation of the oxidized DNA base may contribute to the development of endometrial neoplasia, however oxidative DNA damage does not seem to increase with tumor progression.

  16. Image accuracy and representational enhancement through low-level, multi-sensor integration techniques

    International Nuclear Information System (INIS)

    Baker, J.E.

    1993-05-01

    Multi-Sensor Integration (MSI) is the combining of data and information from more than one source in order to generate a more reliable and consistent representation of the environment. The need for MSI derives largely from basic ambiguities inherent in our current sensor imaging technologies. These ambiguities exist as long as the mapping from reality to image is not 1-to-1. That is, if different 44 realities'' lead to identical images, a single image cannot reveal the particular reality which was the truth. MSI techniques can be divided into three categories based on the relative information content of the original images with that of the desired representation: (1) ''detail enhancement,'' wherein the relative information content of the original images is less rich than the desired representation; (2) ''data enhancement,'' wherein the MSI techniques axe concerned with improving the accuracy of the data rather than either increasing or decreasing the level of detail; and (3) ''conceptual enhancement,'' wherein the image contains more detail than is desired, making it difficult to easily recognize objects of interest. In conceptual enhancement one must group pixels corresponding to the same conceptual object and thereby reduce the level of extraneous detail. This research focuses on data and conceptual enhancement algorithms. To be useful in many real-world applications, e.g., autonomous or teleoperated robotics, real-time feedback is critical. But, many MSI/image processing algorithms require significant processing time. This is especially true of feature extraction, object isolation, and object recognition algorithms due to their typical reliance on global or large neighborhood information. This research attempts to exploit the speed currently available in state-of-the-art digitizers and highly parallel processing systems by developing MSI algorithms based on pixel rather than global-level features

  17. Knowledge-based low-level image analysis for computer vision systems

    Science.gov (United States)

    Dhawan, Atam P.; Baxi, Himanshu; Ranganath, M. V.

    1988-01-01

    Two algorithms for entry-level image analysis and preliminary segmentation are proposed which are flexible enough to incorporate local properties of the image. The first algorithm involves pyramid-based multiresolution processing and a strategy to define and use interlevel and intralevel link strengths. The second algorithm, which is designed for selected window processing, extracts regions adaptively using local histograms. The preliminary segmentation and a set of features are employed as the input to an efficient rule-based low-level analysis system, resulting in suboptimal meaningful segmentation.

  18. Fluid-fluid level on MR image: significance in Musculoskeletal diseases

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hye Won; Lee, Kyung Won [Seoul Naitonal University, Seoul (Korea, Republic of). Coll. of Medicine; Song, Chi Sung [Seoul City Boramae Hospital, Seoul (Korea, Republic of); Han, Sang Wook; Kang, Heung Sik [Seoul Naitonal University, Seoul (Korea, Republic of). Coll. of Medicine

    1998-01-01

    To evaluate the frequency, number and signal intensity of fluid-fluid levels of musculoskeletal diseases on MR images, and to determine the usefulness of this information for the differentiation of musculoskeletal diseases. MR images revealed fluid-fluid levels in the following diseases : giant cell tumor(6), telangiectatic osteosarcoma(4), aneurysmal bone cyst(3), synovial sarcoma(3), chondroblastoma(2), soft tissue tuberculous abscess(2), hematoma(2), hemangioma (1), neurilemmoma(1), metastasis(1), malignant fibrous histiocytoma(1), bursitis(1), pyogenic abscess(1), and epidermoid inclusion cyst(1). Fourteen benign tumors and ten malignant, three abscesses, and the epidermoid inclusion cyst showed only one fluid-fluid level in a unilocular cyst. On T1-weighted images, the signal intensities of fluid varied, but on T2-weighted images, superior layers were in most cases more hyperintense than inferior layers. Because fluid-fluid layers are a nonspecific finding, it is difficult to specifically diagnose each disease according to the number of fluid-fluid levels or signal intensity of fluid. In spite of the nonspecificity of fluid-fluid levels, they were frequently seen in cases of giant cell tumor, telangiectatic osteosarcoma, aneurysmal bone cycle, and synovial sarcoma. Nontumorous diseases such abscesses and hematomas also demonstrated this finding. (author). 11 refs., 1 tab., 4 figs.

  19. Fluid-fluid level on MR image: significance in Musculoskeletal diseases

    International Nuclear Information System (INIS)

    Chung, Hye Won; Lee, Kyung Won; Han, Sang Wook; Kang, Heung Sik

    1998-01-01

    To evaluate the frequency, number and signal intensity of fluid-fluid levels of musculoskeletal diseases on MR images, and to determine the usefulness of this information for the differentiation of musculoskeletal diseases. MR images revealed fluid-fluid levels in the following diseases : giant cell tumor(6), telangiectatic osteosarcoma(4), aneurysmal bone cyst(3), synovial sarcoma(3), chondroblastoma(2), soft tissue tuberculous abscess(2), hematoma(2), hemangioma (1), neurilemmoma(1), metastasis(1), malignant fibrous histiocytoma(1), bursitis(1), pyogenic abscess(1), and epidermoid inclusion cyst(1). Fourteen benign tumors and ten malignant, three abscesses, and the epidermoid inclusion cyst showed only one fluid-fluid level in a unilocular cyst. On T1-weighted images, the signal intensities of fluid varied, but on T2-weighted images, superior layers were in most cases more hyperintense than inferior layers. Because fluid-fluid layers are a nonspecific finding, it is difficult to specifically diagnose each disease according to the number of fluid-fluid levels or signal intensity of fluid. In spite of the nonspecificity of fluid-fluid levels, they were frequently seen in cases of giant cell tumor, telangiectatic osteosarcoma, aneurysmal bone cycle, and synovial sarcoma. Nontumorous diseases such abscesses and hematomas also demonstrated this finding. (author). 11 refs., 1 tab., 4 figs

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

    International Nuclear Information System (INIS)

    Yuan Xinyu; Xie Sheng; Xiao Jiangxi; Zhang Yuanzhe; Jiang Xuexiang; Jin Chunhua; Bai Zhenhua; Yi Xiaoli

    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) × 10 6 mm 3 ] in relative to the controls [(0.956±0.059)×10 6 mm 3 , t=-2.80, 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. (authors)

  1. Acute cervical spine injuries: prospective MR imaging assessment at a level 1 trauma center.

    Science.gov (United States)

    Katzberg, R W; Benedetti, P F; Drake, C M; Ivanovic, M; Levine, R A; Beatty, C S; Nemzek, W R; McFall, R A; Ontell, F K; Bishop, D M; Poirier, V C; Chong, B W

    1999-10-01

    To determine the weighted average sensitivity of magnetic resonance (MR) imaging in the prospective detection of acute neck injury and to compare these findings with those of a comprehensive conventional radiographic assessment. Conventional radiography and MR imaging were performed in 199 patients presenting to a level 1 trauma center with suspected cervical spine injury. Weighted sensitivities and specificities were calculated, and a weighted average across eight vertebral levels from C1 to T1 was formed. Fourteen parameters indicative of acute injury were tabulated. Fifty-eight patients had 172 acute cervical injuries. MR imaging depicted 136 (79%) acute abnormalities and conventional radiography depicted 39 (23%). For assessment of acute fractures, MR images (weighted average sensitivity, 43%; CI: 21%, 66%) were comparable to conventional radiographs (weighted average sensitivity, 48%; CI: 30%, 65%). MR imaging was superior to conventional radiography in the evaluation of pre- or paravertebral hemorrhage or edema, anterior or posterior longitudinal ligament injury, traumatic disk herniation, cord edema, and cord compression. Cord injuries were associated with cervical spine spondylosis (P < .05), acute fracture (P < .001), and canal stenosis (P < .001). MR imaging is more accurate than radiography in the detection of a wide spectrum of neck injuries, and further study is warranted of its potential effect on medical decision making, clinical outcome, and cost-effectiveness.

  2. Information fusion for the Gray Zone

    Science.gov (United States)

    Fenstermacher, Laurie

    2016-05-01

    United States Special Operations Command (SOCOM) recently published a white paper describing the "Gray Zone", security challenges characterized by "ambiguity about the nature of the conflict, opacity of the parties involved…competitive interactions among and within state and non-state actors that fall between the traditional war and peace duality."1 Ambiguity and related uncertainty about actors, situations, relationships, and intent require new approaches to information collection, processing and fusion. General Votel, the current SOCOM commander, during a recent speech on "Operating in the Gray Zone" emphasized that it would be important to get left of the next crises and stated emphatically, "to do that we must understand the Human Domain."2 This understanding of the human domain must come from making meaning based on different perspectives, including the "emic" or first person/participant and "etic" or third person/observer perspectives. Much of the information currently collected and processed is etic. Incorporation and fusion with the emic perspective enables forecasting of behaviors/events and provides context for etic information (e.g., video).3 Gray zone challenges are perspective-dependent; for example, the conflict in Ukraine is interpreted quite differently by Russia, the US and Ukraine. Russia views it as war, necessitating aggressive action, the US views it as a security issue best dealt with by economic sanctions and diplomacy and the Ukraine views it as a threat to its sovereignty.4 General Otto in the Air Force ISR 2023 vision document stated that Air Force ISR is needed to anticipate strategic surprise.5 Anticipatory analysis enabling getting left of a crisis inherently requires a greater focus on information sources that elucidate the human environment as well as new methods that elucidate not only the "who's" and "what's", but the "how's and "why's," extracting features and/or patterns and subtle cues useful for forecasting behaviors and

  3. AN AUTOMATIC OPTICAL AND SAR IMAGE REGISTRATION METHOD USING ITERATIVE MULTI-LEVEL AND REFINEMENT MODEL

    Directory of Open Access Journals (Sweden)

    C. Xu

    2016-06-01

    Full Text Available Automatic image registration is a vital yet challenging task, particularly for multi-sensor remote sensing images. Given the diversity of the data, it is unlikely that a single registration algorithm or a single image feature will work satisfactorily for all applications. Focusing on this issue, the mainly contribution of this paper is to propose an automatic optical-to-SAR image registration method using –level and refinement model: Firstly, a multi-level strategy of coarse-to-fine registration is presented, the visual saliency features is used to acquire coarse registration, and then specific area and line features are used to refine the registration result, after that, sub-pixel matching is applied using KNN Graph. Secondly, an iterative strategy that involves adaptive parameter adjustment for re-extracting and re-matching features is presented. Considering the fact that almost all feature-based registration methods rely on feature extraction results, the iterative strategy improve the robustness of feature matching. And all parameters can be automatically and adaptively adjusted in the iterative procedure. Thirdly, a uniform level set segmentation model for optical and SAR images is presented to segment conjugate features, and Voronoi diagram is introduced into Spectral Point Matching (VSPM to further enhance the matching accuracy between two sets of matching points. Experimental results show that the proposed method can effectively and robustly generate sufficient, reliable point pairs and provide accurate registration.

  4. Radiation therapists' perceptions of the minimum level of experience required to perform portal image analysis

    International Nuclear Information System (INIS)

    Rybovic, Michala; Halkett, Georgia K.; Banati, Richard B.; Cox, Jennifer

    2008-01-01

    Background and purpose: Our aim was to explore radiation therapists' views on the level of experience necessary to undertake portal image analysis and clinical decision making. Materials and methods: A questionnaire was developed to determine the availability of portal imaging equipment in Australia and New Zealand. We analysed radiation therapists' responses to a specific question regarding their opinion on the minimum level of experience required for health professionals to analyse portal images. We used grounded theory and a constant comparative method of data analysis to derive the main themes. Results: Forty-six radiation oncology facilities were represented in our survey, with 40 questionnaires being returned (87%). Thirty-seven radiation therapists answered our free-text question. Radiation therapists indicated three main themes which they felt were important in determining the minimum level of experience: 'gaining on-the-job experience', 'receiving training' and 'working as a team'. Conclusions: Radiation therapists indicated that competence in portal image review occurs via various learning mechanisms. Further research is warranted to determine perspectives of other health professionals, such as radiation oncologists, on portal image review becoming part of radiation therapists' extended role. Suitable training programs and steps for implementation should be developed to facilitate this endeavour

  5. Two-level image authentication by two-step phase-shifting interferometry and compressive sensing

    Science.gov (United States)

    Zhang, Xue; Meng, Xiangfeng; Yin, Yongkai; Yang, Xiulun; Wang, Yurong; Li, Xianye; Peng, Xiang; He, Wenqi; Dong, Guoyan; Chen, Hongyi

    2018-01-01

    A two-level image authentication method is proposed; the method is based on two-step phase-shifting interferometry, double random phase encoding, and compressive sensing (CS) theory, by which the certification image can be encoded into two interferograms. Through discrete wavelet transform (DWT), sparseness processing, Arnold transform, and data compression, two compressed signals can be generated and delivered to two different participants of the authentication system. Only the participant who possesses the first compressed signal attempts to pass the low-level authentication. The application of Orthogonal Match Pursuit CS algorithm reconstruction, inverse Arnold transform, inverse DWT, two-step phase-shifting wavefront reconstruction, and inverse Fresnel transform can result in the output of a remarkable peak in the central location of the nonlinear correlation coefficient distributions of the recovered image and the standard certification image. Then, the other participant, who possesses the second compressed signal, is authorized to carry out the high-level authentication. Therefore, both compressed signals are collected to reconstruct the original meaningful certification image with a high correlation coefficient. Theoretical analysis and numerical simulations verify the feasibility of the proposed method.

  6. [Influence of human body target's spectral characteristics on visual range of low light level image intensifiers].

    Science.gov (United States)

    Zhang, Jun-Ju; Yang, Wen-Bin; Xu, Hui; Liu, Lei; Tao, Yuan-Yaun

    2013-11-01

    To study the effect of different human target's spectral reflective characteristic on low light level (LLL) image intensifier's distance, based on the spectral characteristics of the night-sky radiation and the spectral reflective coefficients of common clothes, we established a equation of human body target's spectral reflective distribution, and analyzed the spectral reflective characteristics of different human targets wearing the clothes of different color and different material, and from the actual detection equation of LLL image intensifier distance, discussed the detection capability of LLL image intensifier for different human target. The study shows that the effect of different human target's spectral reflective characteristic on LLL image intensifier distance is mainly reflected in the average reflectivity rho(-) and the initial contrast of the target and the background C0. Reflective coefficient and spectral reflection intensity of cotton clothes are higher than polyester clothes, and detection capability of LLL image intensifier is stronger for the human target wearing cotton clothes. Experimental results show that the LLL image intensifiers have longer visual ranges for targets who wear cotton clothes than targets who wear same color but polyester clothes, and have longer visual ranges for targets who wear light-colored clothes than targets who wear dark-colored clothes. And in the full moon illumination conditions, LLL image intensifiers are more sensitive to the clothes' material.

  7. Value of contrast-enhanced sonographic micro flow imaging for prostate cancer detection with t-PSA level of 4–10 ng/mL

    International Nuclear Information System (INIS)

    Guo, Yi-Fen; Li, Feng-Hua; Xie, Shao-Wei; Xia, Jian-Guo; Fang, Hua; Li, Hong-Li

    2012-01-01

    Objectives: To compare the efficiency of contrast-enhanced ultrasonographic micro flow imaging (MFI) with conventional transrectal ultrasound (TRUS) in detecting prostate cancer with serum total prostate-specific antigen (t-PSA) of 4.0–10.0 ng/mL. To evaluate the value of contrast-enhanced ultrasonographic MFI in detecting prostate cancer with t-PSA in diagnostic gray zone. Methods: 47 patients with t-PSA 4.0–10.0 ng/mL underwent gray scale, power Doppler TRUS and MFI examinations before ultrasound guided biopsies. Biopsies were performed at twelve sites in the base, the mid-gland and the apex of the prostate in each patient, when there was no abnormal ultrasound finding. When an abnormality was present at MFI, the biopsy specimen from the corresponding site was directed toward the abnormal finding. With histological results of prostate biopsy as reference standards, we assessed the cancer detection of these three methods. Results: 564 specimens were collected in this study, in which 101 were prostate cancer confirmed histologically. 152 of 564 specimens were demonstrated abnormal on MFI images, in which 71 were malignant and 81 were benign confirmed histologically. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) for MFI in detecting prostate caner were 70.3%, 82.5%, 80.3%, 46.7% and 92.7%, respectively. The sensitivity and NPV for MFI were significantly better than gray scale (38.6%, 86.9%) and power Doppler (32.7%, 86.0%) (P < 0.001) TRUS. Conclusions: Contrast-enhanced ultrasonographic MFI could significantly improve the detection rate of prostate cancer with t-PSA in diagnostic gray zone (4–10 ng/mL) than conventional ultrasound.

  8. Automated ventricular systems segmentation in brain CT images by combining low-level segmentation and high-level template matching

    Directory of Open Access Journals (Sweden)

    Ward Kevin R

    2009-11-01

    Full Text Available Abstract Background Accurate analysis of CT brain scans is vital for diagnosis and treatment of Traumatic Brain Injuries (TBI. Automatic processing of these CT brain scans could speed up the decision making process, lower the cost of healthcare, and reduce the chance of human error. In this paper, we focus on automatic processing of CT brain images to segment and identify the ventricular systems. The segmentation of ventricles provides quantitative measures on the changes of ventricles in the brain that form vital diagnosis information. Methods First all CT slices are aligned by detecting the ideal midlines in all images. The initial estimation of the ideal midline of the brain is found based on skull symmetry and then the initial estimate is further refined using detected anatomical features. Then a two-step method is used for ventricle segmentation. First a low-level segmentation on each pixel is applied on the CT images. For this step, both Iterated Conditional Mode (ICM and Maximum A Posteriori Spatial Probability (MASP are evaluated and compared. The second step applies template matching algorithm to identify objects in the initial low-level segmentation as ventricles. Experiments for ventricle segmentation are conducted using a relatively large CT dataset containing mild and severe TBI cases. Results Experiments show that the acceptable rate of the ideal midline detection is over 95%. Two measurements are defined to evaluate ventricle recognition results. The first measure is a sensitivity-like measure and the second is a false positive-like measure. For the first measurement, the rate is 100% indicating that all ventricles are identified in all slices. The false positives-like measurement is 8.59%. We also point out the similarities and differences between ICM and MASP algorithms through both mathematically relationships and segmentation results on CT images. Conclusion The experiments show the reliability of the proposed algorithms. The

  9. Automatic segmentation of Leishmania parasite in microscopic images using a modified CV level set method

    Science.gov (United States)

    Farahi, Maria; Rabbani, Hossein; Talebi, Ardeshir; Sarrafzadeh, Omid; Ensafi, Shahab

    2015-12-01

    Visceral Leishmaniasis is a parasitic disease that affects liver, spleen and bone marrow. According to World Health Organization report, definitive diagnosis is possible just by direct observation of the Leishman body in the microscopic image taken from bone marrow samples. We utilize morphological and CV level set method to segment Leishman bodies in digital color microscopic images captured from bone marrow samples. Linear contrast stretching method is used for image enhancement and morphological method is applied to determine the parasite regions and wipe up unwanted objects. Modified global and local CV level set methods are proposed for segmentation and a shape based stopping factor is used to hasten the algorithm. Manual segmentation is considered as ground truth to evaluate the proposed method. This method is tested on 28 samples and achieved 10.90% mean of segmentation error for global model and 9.76% for local model.

  10. Lossless, Near-Lossless, and Refinement Coding of Bi-level Images

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren Otto

    1997-01-01

    We present general and unified algorithms for lossy/lossless codingof bi-level images. The compression is realized by applying arithmetic coding to conditional probabilities. As in the current JBIG standard the conditioning may be specified by a template.For better compression, the more general....... Introducing only a small amount of loss in halftoned test images, compression is increased by up to a factor of four compared with JBIG. Lossy, lossless, and refinement decoding speed and lossless encoding speed are less than a factor of two slower than JBIG. The (de)coding method is proposed as part of JBIG......-2, an emerging international standard for lossless/lossy compression of bi-level images....

  11. Lossless, Near-Lossless, and Refinement Coding of Bi-level Images

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren Otto

    1999-01-01

    We present general and unified algorithms for lossy/lossless coding of bi-level images. The compression is realized by applying arithmetic coding to conditional probabilities. As in the current JBIG standard the conditioning may be specified by a template.For better compression, the more general...... to the specialized soft pattern matching techniques which work better for text. Template based refinement coding is applied for lossy-to-lossless refinement. Introducing only a small amount of loss in halftoned test images, compression is increased by up to a factor of four compared with JBIG. Lossy, lossless......, and refinement decoding speed and lossless encoding speed are less than a factor of two slower than JBIG. The (de)coding method is proposed as part of JBIG2, an emerging international standard for lossless/lossy compression of bi-level images....

  12. Effect of administered radioactive dose level on image quality of brain perfusion imaging with 99mTc-HMPAO

    Directory of Open Access Journals (Sweden)

    I.Armeniakos

    2008-01-01

    Full Text Available Brain perfusion imaging by means of 99mTc-labeled hexamethyl propylene amine oxime (HMPAO is a well-established Nuclear Medicine diagnostic procedure. The administered dose range recommended by the supplying company and reported in bibliography is rather wide (approximately 9.5-27 mCi. This fact necessitates further quantitative analysis of the technique, so as to minimise patient absorbed dose without compromising the examination diagnostic value. In this study, a quantitative evaluation of the radiopharmaceutical performance for different values of administered dose (10, 15, 20 mCi was carried out. Subsequently, a generic image quality index was correlated with the administered dose, to produce an overall performance indicator. Through this cost-to-benefit type analysis, the necessity of administration of higher radioactive dose levels in order to perform the specific diagnostic procedure was examined.Materials & methods: The study was based on a sample of 78 patients (56 administered with 10 mCi, 10 with 15 mCi and 12 with 20 mCi. Some patients were classified as normal, while others presented various forms of pathology. Evaluation of image quality was based on contrast, noise and contrast-to-noise ratio indicators, denoted CI, NI and CNR respectively. Calculation of all indicators was based on wavelet transform. An overall performance indicator (denoted PI, produced by the ratio of CNR by administered dose, was also calculated.Results: Calculation of skewness parameter revealed the normality of CI, NI and non-normality of CNR, PI populations. Application of appropriate statistical tests (analysis of variance for normal and Kruskal-Wallis test for non-normal populations showed that there is a statistically significant difference in CI (p0.05 values. Application of Tukey test for normal populations CI, NI led to the conclusion that CI(10 mCi = CI(20 mCiNI(20 mCi, while NI(15 mCi can not be characterised. Finally, application of non

  13. Gray Zone Legislation and Activities: Evaluating the Orchestration of Convergence Within the Gray Zone

    Science.gov (United States)

    2017-06-01

    The Agency and the Hill (Government Printing Office, 2008), 8. 16 Lowenthal, Intelligence . 17 Marshall Erwin, Covert Action: Legislative Background...military and intelligence activities within the Gray Zone and what directs their convergence. More specifically, the author analyzes the...determining convergence or divergence. In the end, classical military theory directs the convergence and divergence of military and intelligence activities

  14. Quantitative myocardial perfusion PET parametric imaging at the voxel-level

    International Nuclear Information System (INIS)

    Mohy-ud-Din, Hassan; Rahmim, Arman; Lodge, Martin A

    2015-01-01

    Quantitative myocardial perfusion (MP) PET has the potential to enhance detection of early stages of atherosclerosis or microvascular dysfunction, characterization of flow-limiting effects of coronary artery disease (CAD), and identification of balanced reduction of flow due to multivessel stenosis. We aim to enable quantitative MP-PET at the individual voxel level, which has the potential to allow enhanced visualization and quantification of myocardial blood flow (MBF) and flow reserve (MFR) as computed from uptake parametric images. This framework is especially challenging for the 82 Rb radiotracer. The short half-life enables fast serial imaging and high patient throughput; yet, the acquired dynamic PET images suffer from high noise-levels introducing large variability in uptake parametric images and, therefore, in the estimates of MBF and MFR. Robust estimation requires substantial post-smoothing of noisy data, degrading valuable functional information of physiological and pathological importance. We present a feasible and robust approach to generate parametric images at the voxel-level that substantially reduces noise without significant loss of spatial resolution. The proposed methodology, denoted physiological clustering, makes use of the functional similarity of voxels to penalize deviation of voxel kinetics from physiological partners. The results were validated using extensive simulations (with transmural and non-transmural perfusion defects) and clinical studies. Compared to post-smoothing, physiological clustering depicted enhanced quantitative noise versus bias performance as well as superior recovery of perfusion defects (as quantified by CNR) with minimal increase in bias. Overall, parametric images obtained from the proposed methodology were robust in the presence of high-noise levels as manifested in the voxel time-activity-curves. (paper)

  15. Examination of image diagnosis system at high level emergency medical service

    International Nuclear Information System (INIS)

    Hirose, Masaharu; Endo, Toshio; Aoki, Tomio

    1983-01-01

    This is a report of the basic idea on imaging system focussing on a necessary X-ray system for high-level emergencies which was worked out due to the establishment of the independent emergency medical institute specialized in the tertiary lifesaving and emergency, and of examinations on satisfactory results we gained for about three years of usage. (author)

  16. Spatiotemporal Analysis of RGB-D-T Facial Images for Multimodal Pain Level Recognition

    DEFF Research Database (Denmark)

    Irani, Ramin; Nasrollahi, Kamal; Oliu Simon, Marc

    2015-01-01

    facial images for pain detection and pain intensity level recognition. For this purpose, we extract energies released by facial pixels using a spatiotemporal filter. Experiments on a group of 12 elderly people applying the multimodal approach show that the proposed method successfully detects pain...

  17. Exploiting street-level panoramic images for large-scale automated surveying of traffic sign

    NARCIS (Netherlands)

    Hazelhoff, L.; Creusen, I.M.; With, de P.H.N.

    2014-01-01

    Accurate and up-to-date inventories of traffic signs contribute to efficient road maintenance and a high road safety. This paper describes a system for the automated surveying of road signs from street-level images. This is an extremely challenging task, as the involved capturings are non-densely

  18. Estimating 3D Object Parameters from 2D Grey-Level Images

    NARCIS (Netherlands)

    Houkes, Z.

    2000-01-01

    This thesis describes a general framework for parameter estimation, which is suitable for computer vision applications. The approach described combines 3D modelling, animation and estimation tools to determine parameters of objects in a scene from 2D grey-level images. The animation tool predicts

  19. Multi-domain, higher order level set scheme for 3D image segmentation on the GPU

    DEFF Research Database (Denmark)

    Sharma, Ojaswa; Zhang, Qin; Anton, François

    2010-01-01

    to evaluate level set surfaces that are $C^2$ continuous, but are slow due to high computational burden. In this paper, we provide a higher order GPU based solver for fast and efficient segmentation of large volumetric images. We also extend the higher order method to multi-domain segmentation. Our streaming...

  20. PET MRI Coregistration in Intractable Epilepsy and Gray Matter Heterotopia.

    Science.gov (United States)

    Seniaray, Nikhil; Jain, Anuj

    2017-03-01

    A 25-year-old woman with intractable seizures underwent FDG PET/MRI for seizure focus localization. MRI demonstrated bilateral carpetlike nodular subependymal gray matter and asymmetrical focal dilatation in the right temporal horn. PET/MRI showed increased FDG within subependymal gray matter with significant hypometabolism in right anterior temporal lobe. EEG and ictal semiology confirmed the right temporal seizure origin. This case highlights the importance of identification of gray matter heterotopia on FDG PET/MRI.

  1. Dichromatic Gray Pixel for Camera-agnostic Color Constancy

    OpenAIRE

    Qian, Yanlin; Chen, Ke; Nikkanen, Jarno; Kämäräinen, Joni-Kristian; Matas, Jiri

    2018-01-01

    We propose a novel statistical color constancy method, especially suitable for the Camera-agnostic Color Constancy, i.e. the scenario where nothing is known a priori about the capturing devices. The method, called Dichromatic Gray Pixel, or DGP, relies on a novel gray pixel detection algorithm derived using the Dichromatic Reflection Model. DGP is suitable for camera-agnostic color constancy since varying devices are set to make achromatic pixels look gray under standard neutral illumination....

  2. Normal gray and white matter volume after weight restoration in adolescents with anorexia nervosa.

    Science.gov (United States)

    Lázaro, Luisa; Andrés, Susana; Calvo, Anna; Cullell, Clàudia; Moreno, Elena; Plana, M Teresa; Falcón, Carles; Bargalló, Núria; Castro-Fornieles, Josefina

    2013-12-01

    The aim of this study was to determine whether treated, weight-stabilized adolescents with anorexia nervosa (AN) present brain volume differences in comparison with healthy controls. Thirty-five adolescents with weight-recovered AN and 17 healthy controls were assessed by means of psychopathology scales and magnetic resonance imaging. Axial three-dimensional T1-weighted images were obtained in a 1.5 Tesla scanner and analyzed using optimized voxel-based morphometry (VBM). There were no significant differences between controls and weight-stabilized AN patients with regard to global volumes of either gray or white brain matter, or in the regional VBM study. Differences were not significant between patients with psychopharmacological treatment and without, between those with amenorrhea and without, as well as between patients with restrictive versus purgative AN. The present findings reveal no global or regional gray or white matter abnormalities in this sample of adolescents following weight restoration. Copyright © 2013 Wiley Periodicals, Inc.

  3. Segmentation of brain parenchymal regions into gray matter and white matter with Alzheimer's disease

    International Nuclear Information System (INIS)

    Tokunaga, Chiaki; Yoshiura, Takashi; Yamashita, Yasuo; Magome, Taiki; Honda, Hiroshi; Arimura, Hidetaka; Toyofuku, Fukai; Ohki, Masafumi

    2010-01-01

    It is very difficult and time consuming for neuroradiologists to estimate the degree of cerebral atrophy based on the volume of cortical regions etc. Our purpose of this study was to develop an automated segmentation of the brain parenchyma into gray and white matter regions with Alzheimer's disease (AD) in three-dimensional (3D) T1-weighted MR images. Our proposed method consisted of extraction of a brain parenchymal region based on a brain model matching and segmentation of the brain parenchyma into gray and white matter regions based on a fuzzy c-means (FCM) algorithm. We applied our proposed method to MR images of the whole brains obtained from 9 cases, including 4 clinically AD cases and 5 control cases. The mean volume percentage of a cortical region (41.7%) to a brain parenchymal region in AD patients was smaller than that (45.2%) in the control subjects (p=0.000462). (author)

  4. GRay: A MASSIVELY PARALLEL GPU-BASED CODE FOR RAY TRACING IN RELATIVISTIC SPACETIMES

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Chi-kwan; Psaltis, Dimitrios; Özel, Feryal [Department of Astronomy, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721 (United States)

    2013-11-01

    We introduce GRay, a massively parallel integrator designed to trace the trajectories of billions of photons in a curved spacetime. This graphics-processing-unit (GPU)-based integrator employs the stream processing paradigm, is implemented in CUDA C/C++, and runs on nVidia graphics cards. The peak performance of GRay using single-precision floating-point arithmetic on a single GPU exceeds 300 GFLOP (or 1 ns per photon per time step). For a realistic problem, where the peak performance cannot be reached, GRay is two orders of magnitude faster than existing central-processing-unit-based ray-tracing codes. This performance enhancement allows more effective searches of large parameter spaces when comparing theoretical predictions of images, spectra, and light curves from the vicinities of compact objects to observations. GRay can also perform on-the-fly ray tracing within general relativistic magnetohydrodynamic algorithms that simulate accretion flows around compact objects. Making use of this algorithm, we calculate the properties of the shadows of Kerr black holes and the photon rings that surround them. We also provide accurate fitting formulae of their dependencies on black hole spin and observer inclination, which can be used to interpret upcoming observations of the black holes at the center of the Milky Way, as well as M87, with the Event Horizon Telescope.

  5. The greenhouse effect in a gray planetary atmosphere.

    Science.gov (United States)

    Wildt, R.

    1966-01-01

    Hopf analytical solution for values of ratio of gray absorption coefficients for insolating and escaping radiation /greenhouse parameter/ assumed constant at all depths, presenting temperature distribution graphs

  6. Diagnostic accuracy at several reduced radiation dose levels for CT imaging in the diagnosis of appendicitis

    Science.gov (United States)

    Zhang, Di; Khatonabadi, Maryam; Kim, Hyun; Jude, Matilda; Zaragoza, Edward; Lee, Margaret; Patel, Maitraya; Poon, Cheryce; Douek, Michael; Andrews-Tang, Denise; Doepke, Laura; McNitt-Gray, Shawn; Cagnon, Chris; DeMarco, John; McNitt-Gray, Michael

    2012-03-01

    Purpose: While several studies have investigated the tradeoffs between radiation dose and image quality (noise) in CT imaging, the purpose of this study was to take this analysis a step further by investigating the tradeoffs between patient radiation dose (including organ dose) and diagnostic accuracy in diagnosis of appendicitis using CT. Methods: This study was IRB approved and utilized data from 20 patients who underwent clinical CT exams for indications of appendicitis. Medical record review established true diagnosis of appendicitis, with 10 positives and 10 negatives. A validated software tool used raw projection data from each scan to create simulated images at lower dose levels (70%, 50%, 30%, 20% of original). An observer study was performed with 6 radiologists reviewing each case at each dose level in random order over several sessions. Readers assessed image quality and provided confidence in their diagnosis of appendicitis, each on a 5 point scale. Liver doses at each case and each dose level were estimated using Monte Carlo simulation based methods. Results: Overall diagnostic accuracy varies across dose levels: 92%, 93%, 91%, 90% and 90% across the 100%, 70%, 50%, 30% and 20% dose levels respectively. And it is 93%, 95%, 88%, 90% and 90% across the 13.5-22mGy, 9.6-13.5mGy, 6.4-9.6mGy, 4-6.4mGy, and 2-4mGy liver dose ranges respectively. Only 4 out of 600 observations were rated "unacceptable" for image quality. Conclusion: The results from this pilot study indicate that the diagnostic accuracy does not change dramatically even at significantly reduced radiation dose.

  7. Structured Light Based 3d Scanning for Specular Surface by the Combination of Gray Code and Phase Shifting

    Science.gov (United States)

    Zhang, Yujia; Yilmaz, Alper

    2016-06-01

    Surface reconstruction using coded structured light is considered one of the most reliable techniques for high-quality 3D scanning. With a calibrated projector-camera stereo system, a light pattern is projected onto the scene and imaged by the camera. Correspondences between projected and recovered patterns are computed in the decoding process, which is used to generate 3D point cloud of the surface. However, the indirect illumination effects on the surface, such as subsurface scattering and interreflections, will raise the difficulties in reconstruction. In this paper, we apply maximum min-SW gray code to reduce the indirect illumination effects of the specular surface. We also analysis the errors when comparing the maximum min-SW gray code and the conventional gray code, which justifies that the maximum min-SW gray code has significant superiority to reduce the indirect illumination effects. To achieve sub-pixel accuracy, we project high frequency sinusoidal patterns onto the scene simultaneously. But for specular surface, the high frequency patterns are susceptible to decoding errors. Incorrect decoding of high frequency patterns will result in a loss of depth resolution. Our method to resolve this problem is combining the low frequency maximum min-SW gray code and the high frequency phase shifting code, which achieves dense 3D reconstruction for specular surface. Our contributions include: (i) A complete setup of the structured light based 3D scanning system; (ii) A novel combination technique of the maximum min-SW gray code and phase shifting code. First, phase shifting decoding with sub-pixel accuracy. Then, the maximum min-SW gray code is used to resolve the ambiguity resolution. According to the experimental results and data analysis, our structured light based 3D scanning system enables high quality dense reconstruction of scenes with a small number of images. Qualitative and quantitative comparisons are performed to extract the advantages of our new

  8. A rapid automatic analyzer and its methodology for effective bentonite content based on image recognition technology

    Directory of Open Access Journals (Sweden)

    Wei Long

    2016-09-01

    Full Text Available Fast and accurate determination of effective bentonite content in used clay bonded sand is very important for selecting the correct mixing ratio and mixing process to obtain high-performance molding sand. Currently, the effective bentonite content is determined by testing the ethylene blue absorbed in used clay bonded sand, which is usually a manual operation with some disadvantages including complicated process, long testing time and low accuracy. A rapid automatic analyzer of the effective bentonite content in used clay bonded sand was developed based on image recognition technology. The instrument consists of auto stirring, auto liquid removal, auto titration, step-rotation and image acquisition components, and processor. The principle of the image recognition method is first to decompose the color images into three-channel gray images based on the photosensitive degree difference of the light blue and dark blue in the three channels of red, green and blue, then to make the gray values subtraction calculation and gray level transformation of the gray images, and finally, to extract the outer circle light blue halo and the inner circle blue spot and calculate their area ratio. The titration process can be judged to reach the end-point while the area ratio is higher than the setting value.

  9. Gray matter anomalies in pedophiles with and without a history of child sexual offending

    OpenAIRE

    Schiffer, B; Amelung, T; Pohl, A; Kaergel, C; Tenbergen, G; Gerwinn, H; Mohnke, S; Massau, C; Matthias, W; Wei?, S; Marr, V; Beier, K M; Walter, M; Ponseti, J; Kr?ger, T H C

    2017-01-01

    Pedophilia is a psychiatric disorder that is inter-related with but distinct from child sexual offending (CSO). Neural alterations reportedly contribute to both pedophilia and CSO, but until now, no study has distinguished the brain structural anomalies associated with pedophilia from those specifically associated with CSO in pedophilic men. Using high-resolution T1-weighted brain images and voxel-based morphometry, we analyzed the gray matter (GM) volume of the following 219 men recruited at...

  10. Altered Gray Matter Volume and White Matter Integrity in College Students with Mobile Phone Dependence

    OpenAIRE

    Wang, Yongming; Zou, Zhiling; Song, Hongwen; Xu, Xiaodan; Wang, Huijun; d?Oleire Uquillas, Federico; Huang, Xiting

    2016-01-01

    Mobile phone dependence (MPD) is a behavioral addiction that has become an increasing public mental health issue. While previous research has explored some of the factors that may predict MPD, the underlying neural mechanisms of MPD have not been investigated yet. The current study aimed to explore the microstructural variations associated with MPD as measured with functional Magnetic Resonance Imaging (fMRI). Gray matter volume (GMV) and white matter (WM) integrity [four indices: fractional ...

  11. An improved level set method for brain MR images segmentation and bias correction.

    Science.gov (United States)

    Chen, Yunjie; Zhang, Jianwei; Macione, Jim

    2009-10-01

    Intensity inhomogeneities cause considerable difficulty in the quantitative analysis of magnetic resonance (MR) images. Thus, bias field estimation is a necessary step before quantitative analysis of MR data can be undertaken. This paper presents a variational level set approach to bias correction and segmentation for images with intensity inhomogeneities. Our method is based on an observation that intensities in a relatively small local region are separable, despite of the inseparability of the intensities in the whole image caused by the overall intensity inhomogeneity. We first define a localized K-means-type clustering objective function for image intensities in a neighborhood around each point. The cluster centers in this objective function have a multiplicative factor that estimates the bias within the neighborhood. The objective function is then integrated over the entire domain to define the data term into the level set framework. Our method is able to capture bias of quite general profiles. Moreover, it is robust to initialization, and thereby allows fully automated applications. The proposed method has been used for images of various modalities with promising results.

  12. Analysis of gene expression levels in individual bacterial cells without image segmentation.

    Science.gov (United States)

    Kwak, In Hae; Son, Minjun; Hagen, Stephen J

    2012-05-11

    Studies of stochasticity in gene expression typically make use of fluorescent protein reporters, which permit the measurement of expression levels within individual cells by fluorescence microscopy. Analysis of such microscopy images is almost invariably based on a segmentation algorithm, where the image of a cell or cluster is analyzed mathematically to delineate individual cell boundaries. However segmentation can be ineffective for studying bacterial cells or clusters, especially at lower magnification, where outlines of individual cells are poorly resolved. Here we demonstrate an alternative method for analyzing such images without segmentation. The method employs a comparison between the pixel brightness in phase contrast vs fluorescence microscopy images. By fitting the correlation between phase contrast and fluorescence intensity to a physical model, we obtain well-defined estimates for the different levels of gene expression that are present in the cell or cluster. The method reveals the boundaries of the individual cells, even if the source images lack the resolution to show these boundaries clearly. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Diagnosing and Ranking Retinopathy Disease Level Using Diabetic Fundus Image Recuperation Approach

    Directory of Open Access Journals (Sweden)

    K. Somasundaram

    2015-01-01

    Full Text Available Retinal fundus images are widely used in diagnosing different types of eye diseases. The existing methods such as Feature Based Macular Edema Detection (FMED and Optimally Adjusted Morphological Operator (OAMO effectively detected the presence of exudation in fundus images and identified the true positive ratio of exudates detection, respectively. These mechanically detected exudates did not include more detailed feature selection technique to the system for detection of diabetic retinopathy. To categorize the exudates, Diabetic Fundus Image Recuperation (DFIR method based on sliding window approach is developed in this work to select the features of optic cup in digital retinal fundus images. The DFIR feature selection uses collection of sliding windows with varying range to obtain the features based on the histogram value using Group Sparsity Nonoverlapping Function. Using support vector model in the second phase, the DFIR method based on Spiral Basis Function effectively ranks the diabetic retinopathy disease level. The ranking of disease level on each candidate set provides a much promising result for developing practically automated and assisted diabetic retinopathy diagnosis system. Experimental work on digital fundus images using the DFIR method performs research on the factors such as sensitivity, ranking efficiency, and feature selection time.

  14. Diagnosing and ranking retinopathy disease level using diabetic fundus image recuperation approach.

    Science.gov (United States)

    Somasundaram, K; Rajendran, P Alli

    2015-01-01

    Retinal fundus images are widely used in diagnosing different types of eye diseases. The existing methods such as Feature Based Macular Edema Detection (FMED) and Optimally Adjusted Morphological Operator (OAMO) effectively detected the presence of exudation in fundus images and identified the true positive ratio of exudates detection, respectively. These mechanically detected exudates did not include more detailed feature selection technique to the system for detection of diabetic retinopathy. To categorize the exudates, Diabetic Fundus Image Recuperation (DFIR) method based on sliding window approach is developed in this work to select the features of optic cup in digital retinal fundus images. The DFIR feature selection uses collection of sliding windows with varying range to obtain the features based on the histogram value using Group Sparsity Nonoverlapping Function. Using support vector model in the second phase, the DFIR method based on Spiral Basis Function effectively ranks the diabetic retinopathy disease level. The ranking of disease level on each candidate set provides a much promising result for developing practically automated and assisted diabetic retinopathy diagnosis system. Experimental work on digital fundus images using the DFIR method performs research on the factors such as sensitivity, ranking efficiency, and feature selection time.

  15. Mid-level image representations for real-time heart view plane classification of echocardiograms.

    Science.gov (United States)

    Penatti, Otávio A B; Werneck, Rafael de O; de Almeida, Waldir R; Stein, Bernardo V; Pazinato, Daniel V; Mendes Júnior, Pedro R; Torres, Ricardo da S; Rocha, Anderson

    2015-11-01

    In this paper, we explore mid-level image representations for real-time heart view plane classification of 2D echocardiogram ultrasound images. The proposed representations rely on bags of visual words, successfully used by the computer vision community in visual recognition problems. An important element of the proposed representations is the image sampling with large regions, drastically reducing the execution time of the image characterization procedure. Throughout an extensive set of experiments, we evaluate the proposed approach against different image descriptors for classifying four heart view planes. The results show that our approach is effective and efficient for the target problem, making it suitable for use in real-time setups. The proposed representations are also robust to different image transformations, e.g., downsampling, noise filtering, and different machine learning classifiers, keeping classification accuracy above 90%. Feature extraction can be performed in 30 fps or 60 fps in some cases. This paper also includes an in-depth review of the literature in the area of automatic echocardiogram view classification giving the reader a through comprehension of this field of study. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Variational Level Set Method for Two-Stage Image Segmentation Based on Morphological Gradients

    Directory of Open Access Journals (Sweden)

    Zemin Ren

    2014-01-01

    Full Text Available We use variational level set method and transition region extraction techniques to achieve image segmentation task. The proposed scheme is done by two steps. We first develop a novel algorithm to extract transition region based on the morphological gradient. After this, we integrate the transition region into a variational level set framework and develop a novel geometric active contour model, which include an external energy based on transition region and fractional order edge indicator function. The external energy is used to drive the zero level set toward the desired image features, such as object boundaries. Due to this external energy, the proposed model allows for more flexible initialization. The fractional order edge indicator function is incorporated into the length regularization term to diminish the influence of noise. Moreover, internal energy is added into the proposed model to penalize the deviation of the level set function from a signed distance function. The results evolution of the level set function is the gradient flow that minimizes the overall energy functional. The proposed model has been applied to both synthetic and real images with promising results.

  17. Effect of blood glucose levels on image quality in 18F fluorodeoxyglucose scanning - a case report

    International Nuclear Information System (INIS)

    Szeto, E.; Keane, J.

    2000-01-01

    Full text: In December last year, a 71-year-old gentleman presented to the Nuclear Medicine Department at St Vincent's Hospital, Sydney for an FDG coincidence detection positron emission scan. The patient had cancer of the lung with a large lesion in the left upper lobe and a small lesion in the right middle lobe. On initial investigation, this patient had a blood sugar level of 17mmol/L which was eventually reduced to 6.7mmol/L just prior to scanning. The patient was then asked to return to be rescanned without his blood sugar levels being adjusted. Just prior to his second scan, his blood sugar level was 15.4mmollL. The aim of the initial scan being repeated was to see just how important a role blood sugar levels play in the quality of a Co Pet scan. The first scan showed excellent image quality while the repeated scan showed markedly inferior image quality due to unwanted soft tissue FDG uptake. In conclusion, blood sugar levels play a significant role in output image quality in FDG coincidence detection positron emission scanning. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc

  18. Two-Level Evaluation on Sensor Interoperability of Features in Fingerprint Image Segmentation

    Directory of Open Access Journals (Sweden)

    Ya-Shuo Li

    2012-03-01

    Full Text Available Features used in fingerprint segmentation significantly affect the segmentation performance. Various features exhibit different discriminating abilities on fingerprint images derived from different sensors. One feature which has better discriminating ability on images derived from a certain sensor may not adapt to segment images derived from other sensors. This degrades the segmentation performance. This paper empirically analyzes the sensor interoperability problem of segmentation feature, which refers to the feature’s ability to adapt to the raw fingerprints captured by different sensors. To address this issue, this paper presents a two-level feature evaluation method, including the first level feature evaluation based on segmentation error rate and the second level feature evaluation based on decision tree. The proposed method is performed on a number of fingerprint databases which are obtained from various sensors. Experimental results show that the proposed method can effectively evaluate the sensor interoperability of features, and the features with good evaluation results acquire better segmentation accuracies of images originating from different sensors.

  19. InGaAs focal plane arrays for low-light-level SWIR imaging

    Science.gov (United States)

    MacDougal, Michael; Hood, Andrew; Geske, Jon; Wang, Jim; Patel, Falgun; Follman, David; Manzo, Juan; Getty, Jonathan

    2011-06-01

    Aerius Photonics will present their latest developments in large InGaAs focal plane arrays, which are used for low light level imaging in the short wavelength infrared (SWIR) regime. Aerius will present imaging in both 1280x1024 and 640x512 formats. Aerius will present characterization of the FPA including dark current measurements. Aerius will also show the results of development of SWIR FPAs for high temperaures, including imagery and dark current data. Finally, Aerius will show results of using the SWIR camera with Aerius' SWIR illuminators using VCSEL technology.

  20. Raised Anxiety Levels Among Outpatients Preparing to Undergo a Medical Imaging Procedure: Prevalence and Correlates.

    Science.gov (United States)

    Forshaw, Kristy L; Boyes, Allison W; Carey, Mariko L; Hall, Alix E; Symonds, Michael; Brown, Sandy; Sanson-Fisher, Rob W

    2018-04-01

    To examine the percentage of patients with raised state anxiety levels before undergoing a medical imaging procedure; their attribution of procedural-related anxiety or worry; and sociodemographic, health, and procedural characteristics associated with raised state anxiety levels. This prospective cross-sectional study was undertaken in the outpatient medical imaging department at a major public hospital in Australia, with institutional board approval. Adult outpatients undergoing a medical imaging procedure (CT, x-ray, MRI, ultrasound, angiography, or fluoroscopy) completed a preprocedural survey. Anxiety was measured by the short-form state scale of the six-item State-Trait Anxiety Inventory (STAI: Y-6). The number and percentage of participants who reported raised anxiety levels (defined as a STAI: Y-6 score ≥ 33.16) and their attribution of procedural-related anxiety or worry were calculated. Characteristics associated with raised anxiety were examined using multiple logistic regression analysis. Of the 548 (86%) patients who consented to participate, 488 (77%) completed all STAI: Y-6 items. Half of the participants (n = 240; 49%) experienced raised anxiety, and of these, 48% (n = 114) reported feeling most anxious or worried about the possible results. Female gender, imaging modality, medical condition, first time having the procedure, and lower patient-perceived health status were statistically significantly associated with raised anxiety levels. Raised anxiety is common before medical imaging procedures and is mostly attributed to the possible results. Providing increased psychological preparation, particularly to patients with circulatory conditions or neoplasms or those that do not know their medical condition, may help reduce preprocedural anxiety among these subgroups. Copyright © 2018 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  1. Level set segmentation of bovine corpora lutea in ex situ ovarian ultrasound images

    Directory of Open Access Journals (Sweden)

    Adams Gregg P

    2008-08-01

    Full Text Available Abstract Background The objective of this study was to investigate the viability of level set image segmentation methods for the detection of corpora lutea (corpus luteum, CL boundaries in ultrasonographic ovarian images. It was hypothesized that bovine CL boundaries could be located within 1–2 mm by a level set image segmentation methodology. Methods Level set methods embed a 2D contour in a 3D surface and evolve that surface over time according to an image-dependent speed function. A speed function suitable for segmentation of CL's in ovarian ultrasound images was developed. An initial contour was manually placed and contour evolution was allowed to proceed until the rate of change of the area was sufficiently small. The method was tested on ovarian ultrasonographic images (n = 8 obtained ex situ. A expert in ovarian ultrasound interpretation delineated CL boundaries manually to serve as a "ground truth". Accuracy of the level set segmentation algorithm was determined by comparing semi-automatically determined contours with ground truth contours using the mean absolute difference (MAD, root mean squared difference (RMSD, Hausdorff distance (HD, sensitivity, and specificity metrics. Results and discussion The mean MAD was 0.87 mm (sigma = 0.36 mm, RMSD was 1.1 mm (sigma = 0.47 mm, and HD was 3.4 mm (sigma = 2.0 mm indicating that, on average, boundaries were accurate within 1–2 mm, however, deviations in excess of 3 mm from the ground truth were observed indicating under- or over-expansion of the contour. Mean sensitivity and specificity were 0.814 (sigma = 0.171 and 0.990 (sigma = 0.00786, respectively, indicating that CLs were consistently undersegmented but rarely did the contour interior include pixels that were judged by the human expert not to be part of the CL. It was observed that in localities where gradient magnitudes within the CL were strong due to high contrast speckle, contour expansion stopped too early. Conclusion The

  2. Sandhill crane abundance and nesting ecology at Grays Lake, Idaho

    Science.gov (United States)

    Austin, J.E.; Henry, A.R.; Ball, I.J.

    2007-01-01

    We examined population size and factors influencing nest survival of greater sandhill cranes (Grus canadensis tabida) at Grays Lake National Wildlife Refuge, Idaho, USA, during 1997-2000. Average local population of cranes from late April to early May, 1998-2000, was 735 cranes, 34% higher than that reported for May 1970-1971. We estimated 228 (SE = 30) nests in the basin core (excluding renests), 14% higher than a 1971 estimate. Apparent nest success in our study (x?? = 60%, n = 519 nests) was lower than reported for Grays Lake 30-50 years earlier. Daily survival rates (DSRs) of all nests averaged 0.9707 (41.2%). The best model explaining nest survival included year and water depth and their interaction. Nest survival was highest (DSR = 0.9827) in 1998 compared with other years (0.9698-0.9707). Nest survival changed little relative to water depth in 1998, when flooding was extensive and alternative prey (microtines) irrupted, but declined markedly with lower water levels in 2000, the driest year studied. Hypotheses relating nest survival to vegetation height, land use (idle, summer grazing, fall grazing), and date were not supported. In a before-after-control-impact design using 12 experimental fields, nest survival differed among years but not among management treatments (idle, fall graze, fall burn, and summer-graze-idle rotation), nor was there an interaction between year and treatments. However, DSRs in fall-burn fields declined from 0.9781 in 1997-1998 to 0.9503 in 1999-2000 (posttreatment). Changes in the predator community have likely contributed to declines in nest success since the 1950s and 1970s. Our results did not support earlier concerns about effects of habitat management practices on crane productivity. Nest survival could best be enhanced by managing spring water levels. Managers should continue censuses during late April to evaluate long-term relationships to habitat conditions and management.

  3. Short-echo 3D H-1 Magnetic Resonance Spectroscopic Imaging of patients with glioma at 7T for characterization of differences in metabolite levels

    Science.gov (United States)

    Li, Yan; Larson, Peder; Chen, Albert P.; Lupo, Janine M.; Ozhinsky, Eugene; Kelley, Douglas; Chang, Susan M.; Nelson, Sarah J.

    2014-01-01

    Purpose The purpose of this study was to evaluate the feasibility of using a short echo time, 3D H-1 magnetic resonance spectroscopic imaging (MRSI) sequence at 7T to assess the metabolic signature of lesions for patients with glioma. Materials and Methods 29 patients with glioma were studied. MRSI data were obtained using CHESS water suppression, spectrally-selective adiabatic inversion-recovery pulses and automatically prescribed outer-volume-suppression for lipid suppression, and spin echo slice selection (TE=30ms). An interleaved flyback echo-planar trajectory was applied to shorten the total acquisition time (~10min). Relative metabolite ratios were estimated in tumor and in normal-appearing white and gray matter (NAWM, GM). Results Levels of glutamine, myo-inositol, glycine and glutathione relative to total creatine (tCr) were significantly increased in the T2 lesions for all tumor grades compared to those in the NAWM (p < 0.05), while N-acetyl aspartate to tCr were significantly decreased (p < 0.05). In grade 2 gliomas, level of total choline-containing-compounds to tCr was significantly increased (p = 0.0137), while glutamate to tCr was significantly reduced (p = 0.0012). Conclusion The improved sensitivity of MRSI and the increased number of metabolites that can be evaluated using 7T MR scanners is of interest for evaluating patients with glioma. This study has successfully demonstrated the application of a short-echo spin-echo MRSI sequence to detect characteristic differences in regions of tumor versus normal appearing brain. PMID:24935758

  4. Relationship between levels of serum creatinine and perirenal hyperintensity on heavily T2-weighted MR images

    Energy Technology Data Exchange (ETDEWEB)

    Erden, Ayse, E-mail: ayse.erden@medicine.ankara.edu.tr [Ankara University, School of Medicine, Department of Radiology, Talatpasa Bulvari, Sihhiye, 06100 Ankara (Turkey); Sahin, Burcu Savran, E-mail: bsavrans@hotmail.com [Ankara University, School of Medicine, Department of Radiology, Talatpasa Bulvari, Sihhiye, 06100 Ankara (Turkey); Orgodol, Horolsuren, E-mail: hoogii99@yahoo.com [Ankara University, School of Medicine, Department of Radiology, Talatpasa Bulvari, Sihhiye, 06100 Ankara (Turkey); Erden, Ilhan, E-mail: erden@medicine.ankara.edu.tr [Ankara University, School of Medicine, Department of Radiology, Talatpasa Bulvari, Sihhiye, 06100 Ankara (Turkey); Biyikli, Zeynep, E-mail: zeynep.biyikli@gmail.com [Ankara University, School of Medicine, Department of Biostatistics, Talatpasa Bulvari, Sihhiye, 06100 Ankara (Turkey)

    2011-11-15

    Objective: To determine the frequency of perirenal hyperintensity on heavily T2-weighted images and to evaluate its relationship with serum creatinine levels. Subjects and methods: Axial and coronal single-shot fast spin-echo images which have been originally obtained for MR cholangiopancreatography in 150 subjects were examined by two observers individually for the presence of perirenal hyperintensity. The morphologic properties of perirenal hyperintensity (peripheral rim-like, discontinuous, polar) were recorded. Chi square test was used to test whether the frequencies of bilateral perirenal hyperintensity differ significantly in subjects with high serum creatinine levels and those with normal creatinine levels. This test was also used to compare the frequencies of perirenal hyperintensity in patients with and without renal cysts and in patients with and without corticomedullary differentiation. A p value of less than 0.05 was considered to be statistically significant. Results: The perirenal hyperintensity was identified in 40 of 150 cases (26.6%) on heavily T2-weighted image. Serum creatinine levels were high in 18 of 150 cases (12%). The perirenal hyperintensity was present in 11 of 18 subjects (61%) with high serum creatinine levels and 26 of 132 subjects (19.7%) with normal creatinine levels. The difference of rates in two groups was statistically significant. Odds ratio was 6407 (95% confidence interval 2264-18,129). The frequency of perirenal hyperintensity was also significantly higher in subjects with renal cyst or cysts in whom serum creatinine levels were normal (p < 0.05) (37.5% vs. 11.8%). Conclusion: Perirenal hyperintensities are more frequent in patients with high serum creatinine levels. They are also more common in patients with simple renal cysts.

  5. Relationship between levels of serum creatinine and perirenal hyperintensity on heavily T2-weighted MR images

    International Nuclear Information System (INIS)

    Erden, Ayse; Sahin, Burcu Savran; Orgodol, Horolsuren; Erden, Ilhan; Biyikli, Zeynep

    2011-01-01

    Objective: To determine the frequency of perirenal hyperintensity on heavily T2-weighted images and to evaluate its relationship with serum creatinine levels. Subjects and methods: Axial and coronal single-shot fast spin-echo images which have been originally obtained for MR cholangiopancreatography in 150 subjects were examined by two observers individually for the presence of perirenal hyperintensity. The morphologic properties of perirenal hyperintensity (peripheral rim-like, discontinuous, polar) were recorded. Chi square test was used to test whether the frequencies of bilateral perirenal hyperintensity differ significantly in subjects with high serum creatinine levels and those with normal creatinine levels. This test was also used to compare the frequencies of perirenal hyperintensity in patients with and without renal cysts and in patients with and without corticomedullary differentiation. A p value of less than 0.05 was considered to be statistically significant. Results: The perirenal hyperintensity was identified in 40 of 150 cases (26.6%) on heavily T2-weighted image. Serum creatinine levels were high in 18 of 150 cases (12%). The perirenal hyperintensity was present in 11 of 18 subjects (61%) with high serum creatinine levels and 26 of 132 subjects (19.7%) with normal creatinine levels. The difference of rates in two groups was statistically significant. Odds ratio was 6407 (95% confidence interval 2264-18,129). The frequency of perirenal hyperintensity was also significantly higher in subjects with renal cyst or cysts in whom serum creatinine levels were normal (p < 0.05) (37.5% vs. 11.8%). Conclusion: Perirenal hyperintensities are more frequent in patients with high serum creatinine levels. They are also more common in patients with simple renal cysts.

  6. Example-Based Image Colorization Using Locality Consistent Sparse Representation.

    Science.gov (United States)

    Bo Li; Fuchen Zhao; Zhuo Su; Xiangguo Liang; Yu-Kun Lai; Rosin, Paul L

    2017-11-01

    Image colorization aims to produce a natural looking color image from a given gray-scale image, which remains a challenging problem. In this paper, we propose a novel example-based image colorization method exploiting a new locality consistent sparse representation. Given a single reference color image, our method automatically colorizes the target gray-scale image by sparse pursuit. For efficiency and robustness, our method operates at the superpixel level. We extract low-level intensity features, mid-level texture features, and high-level semantic features for each superpixel, which are then concatenated to form its descriptor. The collection of feature vectors for all the superpixels from the reference image composes the dictionary. We formulate colorization of target superpixels as a dictionary-based sparse reconstruction problem. Inspired by the observation that superpixels with similar spatial location and/or feature representation are likely to match spatially close regions from the reference image, we further introduce a locality promoting regularization term into the energy formulation, which substantially improves the matching consistency and subsequent colorization results. Target superpixels are colorized based on the chrominance information from the dominant reference superpixels. Finally, to further improve coherence while preserving sharpness, we develop a new edge-preserving filter for chrominance channels with the guidance from the target gray-scale image. To the best of our knowledge, this is the first work on sparse pursuit image colorization from single reference images. Experimental results demonstrate that our colorization method outperforms the state-of-the-art methods, both visually and quantitatively using a user study.

  7. Exposing asymmetric gray matter vulnerability in amyotrophic lateral sclerosis

    Directory of Open Access Journals (Sweden)

    Matthew S. Devine

    2015-01-01

    Full Text Available Limb weakness in amyotrophic lateral sclerosis (ALS is typically asymmetric. Previous studies have identified an effect of limb dominance on onset and spread of weakness, however relative atrophy of dominant and non-dominant brain regions has not been investigated. Our objective was to use voxel-based morphometry (VBM to explore gray matter (GM asymmetry in ALS, in the context of limb dominance. 30 ALS subjects were matched with 17 healthy controls. All subjects were right-handed. Each underwent a structural MRI sequence, from which GM segmentations were generated. Patterns of GM atrophy were assessed in ALS subjects with first weakness in a right-sided limb (n = 15 or left-sided limb (n = 15. Within each group, a voxelwise comparison was also performed between native and mirror GM images, to identify regions of hemispheric GM asymmetry. Subjects with ALS showed disproportionate atrophy of the dominant (left motor cortex hand area, irrespective of the side of first limb weakness (p < 0.01. Asymmetric atrophy of the left somatosensory cortex and temporal gyri was only observed in ALS subjects with right-sided onset of limb weakness. Our VBM protocol, contrasting native and mirror images, was able to more sensitively detect asymmetric GM pathology in a small cohort, compared with standard methods. These findings indicate particular vulnerability of dominant upper limb representation in ALS, supporting previous clinical studies, and with implications for cortical organisation and selective vulnerability.

  8. Exposing asymmetric gray matter vulnerability in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Devine, Matthew S; Pannek, Kerstin; Coulthard, Alan; McCombe, Pamela A; Rose, Stephen E; Henderson, Robert D

    2015-01-01

    Limb weakness in amyotrophic lateral sclerosis (ALS) is typically asymmetric. Previous studies have identified an effect of limb dominance on onset and spread of weakness, however relative atrophy of dominant and non-dominant brain regions has not been investigated. Our objective was to use voxel-based morphometry (VBM) to explore gray matter (GM) asymmetry in ALS, in the context of limb dominance. 30 ALS subjects were matched with 17 healthy controls. All subjects were right-handed. Each underwent a structural MRI sequence, from which GM segmentations were generated. Patterns of GM atrophy were assessed in ALS subjects with first weakness in a right-sided limb (n = 15) or left-sided limb (n = 15). Within each group, a voxelwise comparison was also performed between native and mirror GM images, to identify regions of hemispheric GM asymmetry. Subjects with ALS showed disproportionate atrophy of the dominant (left) motor cortex hand area, irrespective of the side of first limb weakness (p protocol, contrasting native and mirror images, was able to more sensitively detect asymmetric GM pathology in a small cohort, compared with standard methods. These findings indicate particular vulnerability of dominant upper limb representation in ALS, supporting previous clinical studies, and with implications for cortical organisation and selective vulnerability.

  9. Intravital imaging of cardiac function at the single-cell level.

    Science.gov (United States)

    Aguirre, Aaron D; Vinegoni, Claudio; Sebas, Matt; Weissleder, Ralph

    2014-08-05

    Knowledge of cardiomyocyte biology is limited by the lack of methods to interrogate single-cell physiology in vivo. Here we show that contracting myocytes can indeed be imaged with optical microscopy at high temporal and spatial resolution in the beating murine heart, allowing visualization of individual sarcomeres and measurement of the single cardiomyocyte contractile cycle. Collectively, this has been enabled by efficient tissue stabilization, a prospective real-time cardiac gating approach, an image processing algorithm for motion-artifact-free imaging throughout the cardiac cycle, and a fluorescent membrane staining protocol. Quantification of cardiomyocyte contractile function in vivo opens many possibilities for investigating myocardial disease and therapeutic intervention at the cellular level.

  10. Level-set segmentation of pulmonary nodules in megavolt electronic portal images using a CT prior

    International Nuclear Information System (INIS)

    Schildkraut, J. S.; Prosser, N.; Savakis, A.; Gomez, J.; Nazareth, D.; Singh, A. K.; Malhotra, H. K.

    2010-01-01

    Purpose: Pulmonary nodules present unique problems during radiation treatment due to nodule position uncertainty that is caused by respiration. The radiation field has to be enlarged to account for nodule motion during treatment. The purpose of this work is to provide a method of locating a pulmonary nodule in a megavolt portal image that can be used to reduce the internal target volume (ITV) during radiation therapy. A reduction in the ITV would result in a decrease in radiation toxicity to healthy tissue. Methods: Eight patients with nonsmall cell lung cancer were used in this study. CT scans that include the pulmonary nodule were captured with a GE Healthcare LightSpeed RT 16 scanner. Megavolt portal images were acquired with a Varian Trilogy unit equipped with an AS1000 electronic portal imaging device. The nodule localization method uses grayscale morphological filtering and level-set segmentation with a prior. The treatment-time portion of the algorithm is implemented on a graphical processing unit. Results: The method was retrospectively tested on eight cases that include a total of 151 megavolt portal image frames. The method reduced the nodule position uncertainty by an average of 40% for seven out of the eight cases. The treatment phase portion of the method has a subsecond execution time that makes it suitable for near-real-time nodule localization. Conclusions: A method was developed to localize a pulmonary nodule in a megavolt portal image. The method uses the characteristics of the nodule in a prior CT scan to enhance the nodule in the portal image and to identify the nodule region by level-set segmentation. In a retrospective study, the method reduced the nodule position uncertainty by an average of 40% for seven out of the eight cases studied.

  11. Enhancement of image contrast in linacgram through image processing

    International Nuclear Information System (INIS)

    Suh, Hyun Suk; Shin, Hyun Kyo; Lee, Re Na

    2000-01-01

    Conventional radiation therapy portal images gives low contrast images. The purpose of this study was to enhance image contrast of a linacgram by developing a low--cost image processing method. Chest linacgram was obtained by irradiating humanoid phantom and scanned using Diagnostic-Pro scanner for image processing. Several types of scan method were used in scanning. These include optical density scan, histogram equalized scan, linear histogram based scan, linear histogram independent scan, linear optical density scan, logarithmic scan, and power square root scan. The histogram distribution of the scanned images were plotted and the ranges of the gray scale were compared among various scan types. The scanned images were then transformed to the gray window by pallette fitting method and the contrast of the reprocessed portal images were evaluated for image improvement. Portal images of patients were also taken at various anatomic sites and the images were processed by Gray Scale Expansion (GSE) method. The patient images were analyzed to examine the feasibility of using the GSE technique in clinic. The histogram distribution showed that minimum and maximum gray scale ranges of 3192 and 21940 were obtained when the image was scanned using logarithmic method and square root method, respectively. Out of 256 gray scale, only 7 to 30% of the steps were used. After expanding the gray scale to full range, contrast of the portal images were improved. Experiment performed with patient image showed that improved identification of organs were achieved by GSE in portal images of knee joint, head and neck, lung, and pelvis. Phantom study demonstrated that the GSE technique improved image contrast of a linacgram. This indicates that the decrease in image quality resulting from the dual exposure, could be improved by expanding the gray scale. As a result, the improved technique will make it possible to compare the digitally reconstructed radiographs (DRR) and simulation image for

  12. Aberrant paralimbic gray matter in criminal psychopathy.

    Science.gov (United States)

    Ermer, Elsa; Cope, Lora M; Nyalakanti, Prashanth K; Calhoun, Vince D; Kiehl, Kent A

    2012-08-01

    Psychopaths impose large costs on society, as they are frequently habitual, violent criminals. The pervasive nature of emotional and behavioral symptoms in psychopathy suggests that several associated brain regions may contribute to the disorder. Studies employing a variety of methods have converged on a set of brain regions in paralimbic cortex and limbic areas that appear to be dysfunctional in psychopathy. The present study further tests this hypothesis by investigating structural abnormalities using voxel-based morphometry in a sample of incarcerated men (N=296). Psychopathy was associated with decreased regional gray matter in several paralimbic and limbic areas, including bilateral parahippocampal, amygdala, and hippocampal regions, bilateral temporal pole, posterior cingulate cortex, and orbitofrontal cortex. The consistent identification of paralimbic cortex and limbic structures in psychopathy across diverse methodologies strengthens the interpretation that these regions are crucial for understanding neural dysfunction in psychopathy. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  13. Parental Praise Correlates with Posterior Insular Cortex Gray Matter Volume in Children and Adolescents.

    Directory of Open Access Journals (Sweden)

    Izumi Matsudaira

    Full Text Available A positive parenting style affects psychological and cognitive development in children. Neuroimaging studies revealed that a positive parenting style influenced brain structure in children. Parental praise is a concrete behavior observed in positive parenting. Although previous psychological studies revealed a positive effect of parental praise on children, little is known about the relationship between parental praise and brain structure in children. Thus, the purpose of the present study was to determine whether there was a correlation between the parental attitude towards praising their child and gray matter volume in the children (116 boys and 109 girls; mean age, 10.6 years old. We examined the correlation between regional gray matter volume and parental praise using voxel-based morphometry (VBM following magnetic resonance imaging (MRI. In addition, to confirm the positive effects of parental praise, we analyzed the correlation between the frequency of parental praise and personality traits in children. We showed that the parental attitude towards praising their child was significantly and positively correlated with the gray matter volume of the left posterior insular cortex in children. Moreover, we found a significant positive correlation between parental attitude towards praising their child and the personality traits of conscientiousness and openness to experience in the children. Prior studies said that gray matter volume in the posterior insula was correlated with empathy, and the functional connectivity between this area and the amygdala was associated with emotional regulation. Furthermore, the posterior insula relates to auditory function, and therefore, was likely involved in the processing of parental praise. Considering the possibility of experience-dependent plasticity, frequent parental praise would lead to increased posterior insular gray matter volume in children. Our study is the first to elucidate the relationship between

  14. Document authentication at molecular levels using desorption atmospheric pressure chemical ionization mass spectrometry imaging.

    Science.gov (United States)

    Li, Ming; Jia, Bin; Ding, Liying; Hong, Feng; Ouyang, Yongzhong; Chen, Rui; Zhou, Shumin; Chen, Huanwen; Fang, Xiang

    2013-09-01

    Molecular images of documents were obtained by sequentially scanning the surface of the document using desorption atmospheric pressure chemical ionization mass spectrometry (DAPCI-MS), which was operated in either a gasless, solvent-free or methanol vapor-assisted mode. The decay process of the ink used for handwriting was monitored by following the signal intensities recorded by DAPCI-MS. Handwritings made using four types of inks on four kinds of paper surfaces were tested. By studying the dynamic decay of the inks, DAPCI-MS imaging differentiated a 10-min old from two 4 h old samples. Non-destructive forensic analysis of forged signatures either handwritten or computer-assisted was achieved according to the difference of the contour in DAPCI images, which was attributed to the strength personalized by different writers. Distinction of the order of writing/stamping on documents and detection of illegal printings were accomplished with a spatial resolution of about 140 µm. A Matlab® written program was developed to facilitate the visualization of the similarity between signature images obtained by DAPCI-MS. The experimental results show that DAPCI-MS imaging provides rich information at the molecular level and thus can be used for the reliable document analysis in forensic applications. © 2013 The Authors. Journal of Mass Spectrometry published by John Wiley & Sons, Ltd.

  15. Measurement of thermally ablated lesions in sonoelastographic images using level set methods

    Science.gov (United States)

    Castaneda, Benjamin; Tamez-Pena, Jose Gerardo; Zhang, Man; Hoyt, Kenneth; Bylund, Kevin; Christensen, Jared; Saad, Wael; Strang, John; Rubens, Deborah J.; Parker, Kevin J.

    2008-03-01

    The capability of sonoelastography to detect lesions based on elasticity contrast can be applied to monitor the creation of thermally ablated lesion. Currently, segmentation of lesions depicted in sonoelastographic images is performed manually which can be a time consuming process and prone to significant intra- and inter-observer variability. This work presents a semi-automated segmentation algorithm for sonoelastographic data. The user starts by planting a seed in the perceived center of the lesion. Fast marching methods use this information to create an initial estimate of the lesion. Subsequently, level set methods refine its final shape by attaching the segmented contour to edges in the image while maintaining smoothness. The algorithm is applied to in vivo sonoelastographic images from twenty five thermal ablated lesions created in porcine livers. The estimated area is compared to results from manual segmentation and gross pathology images. Results show that the algorithm outperforms manual segmentation in accuracy, inter- and intra-observer variability. The processing time per image is significantly reduced.

  16. Multilevel binomial logistic prediction model for malignant pulmonary nodules based on texture features of CT image

    International Nuclear Information System (INIS)

    Wang Huan; Guo Xiuhua; Jia Zhongwei; Li Hongkai; Liang Zhigang; Li Kuncheng; He Qian

    2010-01-01

    Purpose: To introduce multilevel binomial logistic prediction model-based computer-aided diagnostic (CAD) method of small solitary pulmonary nodules (SPNs) diagnosis by combining patient and image characteristics by textural features of CT image. Materials and methods: Describe fourteen gray level co-occurrence matrix textural features obtained from 2171 benign and malignant small solitary pulmonary nodules, which belongs to 185 patients. Multilevel binomial logistic model is applied to gain these initial insights. Results: Five texture features, including Inertia, Entropy, Correlation, Difference-mean, Sum-Entropy, and age of patients own aggregating character on patient-level, which are statistically different (P < 0.05) between benign and malignant small solitary pulmonary nodules. Conclusion: Some gray level co-occurrence matrix textural features are efficiently descriptive features of CT image of small solitary pulmonary nodules, which can profit diagnosis of earlier period lung cancer if combined patient-level characteristics to some extent.

  17. Combined phase and X-Ray fluorescence imaging at the sub-cellular level

    International Nuclear Information System (INIS)

    Kosior, Ewelina

    2013-01-01

    This work presents some recent developments in the field of hard X-ray imaging applied to biomedical research. As the discipline is evolving quickly, new questions appear and the list of needs becomes bigger. Some of them are dealt with in this manuscript. It has been shown that the ID22NI beamline of the ESRF can serve as a proper experimental setup to investigate diverse aspects of cellular research. Together with its high spatial resolution, high flux and high energy range the experimental setup provides bigger field of view, is less sensitive to radiation damages (while taking phase contrast images) and suits well chemical analysis with emphasis on endogenous metals (Zn, Fe, Mn) but also with a possibility for exogenous one's like these found in nanoparticles (Au, Pt, Ag) study. Two synchrotron-based imaging techniques, fluorescence and phase contrast imaging were used in this research project. They were correlated with each other on a number of biological cases, from bacteria E.coli to various cells (HEK 293, PC12, MRC5VA, red blood cells). The explorations made in the chapter 5 allowed preparation of more established and detailed analysis, described in the next chapter where both techniques, X-ray fluorescence and phase contrast imaging, were exploited in order to access absolute metal projected mass fraction in a whole cell. The final image presents for the first time true quantitative information at the sub-cellular level, not biased by the cell thickness. Thus for the first time a fluorescence map serves as a complete quantitative image of a cell without any risk of misinterpretation. Once both maps are divided by each other pixel by pixel (fluorescence map divided by the phase map) they present a complete and final result of the metal (Zn in this work) projected mass fraction in ppm of dry weight. For the purpose of this calculation the analysis was extended to calibration (non-biological) samples. Polystyrene spheres of a known diameter and known

  18. Medical physics personnel for medical imaging: requirements, conditions of involvement and staffing levels-French recommendations

    International Nuclear Information System (INIS)

    Isambert, Aurelie; Valero, Marc; Rousse, Carole; Blanchard, Vincent; Le Du, Dominique; Guilhem, Marie-Therese; Dieudonne, Arnaud; Pierrat, Noelle; Salvat, Cecile

    2015-01-01

    The French regulations concerning the involvement of medical physicists in medical imaging procedures are relatively vague. In May 2013, the ASN and the SFPM issued recommendations regarding Medical Physics Personnel for Medical Imaging: Requirements, Conditions of Involvement and Staffing Levels. In these recommendations, the various areas of activity of medical physicists in radiology and nuclear medicine have been identified and described, and the time required to perform each task has been evaluated. Criteria for defining medical physics staffing levels are thus proposed. These criteria are defined according to the technical platform, the procedures and techniques practised on it, the number of patients treated and the number of persons in the medical and paramedical teams requiring periodic training. The result of this work is an aid available to each medical establishment to determine their own needs in terms of medical physics. (authors)

  19. Medical physics personnel for medical imaging: requirements, conditions of involvement and staffing levels-French recommendations.

    Science.gov (United States)

    Isambert, Aurélie; Le Du, Dominique; Valéro, Marc; Guilhem, Marie-Thérèse; Rousse, Carole; Dieudonné, Arnaud; Blanchard, Vincent; Pierrat, Noëlle; Salvat, Cécile

    2015-04-01

    The French regulations concerning the involvement of medical physicists in medical imaging procedures are relatively vague. In May 2013, the ASN and the SFPM issued recommendations regarding Medical Physics Personnel for Medical Imaging: Requirements, Conditions of Involvement and Staffing Levels. In these recommendations, the various areas of activity of medical physicists in radiology and nuclear medicine have been identified and described, and the time required to perform each task has been evaluated. Criteria for defining medical physics staffing levels are thus proposed. These criteria are defined according to the technical platform, the procedures and techniques practised on it, the number of patients treated and the number of persons in the medical and paramedical teams requiring periodic training. The result of this work is an aid available to each medical establishment to determine their own needs in terms of medical physics. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Topology-Preserving Rigid Transformation of 2D Digital Images.

    Science.gov (United States)

    Ngo, Phuc; Passat, Nicolas; Kenmochi, Yukiko; Talbot, Hugues

    2014-02-01

    We provide conditions under which 2D digital images preserve their topological properties under rigid transformations. We consider the two most common digital topology models, namely dual adjacency and well-composedness. This paper leads to the proposal of optimal preprocessing strategies that ensure the topological invariance of images under arbitrary rigid transformations. These results and methods are proved to be valid for various kinds of images (binary, gray-level, label), thus providing generic and efficient tools, which can be used in particular in the context of image registration and warping.

  1. MPEG-7 low level image descriptors for modeling users' web pages visual appeal opinion

    OpenAIRE

    Uribe Mayoral, Silvia; Alvarez Garcia, Federico; Menendez Garcia, Jose Manuel

    2015-01-01

    The study of the users' web pages first impression is an important factor for interface designers, due to its influence over the final opinion about a site. In this regard, the analysis of web aesthetics can be considered as an interesting tool for evaluating this early impression, and the use of low level image descriptors for modeling it in an objective way represents an innovative research field. According to this, in this paper we present a new model for website aesthetics evaluation and ...

  2. Proton therapy for prostate cancer treatment employing online image guidance and an action level threshold.

    Science.gov (United States)

    Vargas, Carlos; Falchook, Aaron; Indelicato, Daniel; Yeung, Anamaria; Henderson, Randall; Olivier, Kenneth; Keole, Sameer; Williams, Christopher; Li, Zuofeng; Palta, Jatinder

    2009-04-01

    The ability to determine the accuracy of the final prostate position within a determined action level threshold for image-guided proton therapy is unclear. Three thousand one hundred ten images for 20 consecutive patients treated in 1 of our 3 proton prostate protocols from February to May of 2007 were analyzed. Daily kV images and patient repositioning were performed employing an action-level threshold (ALT) of > or = 2.5 mm for each beam. Isocentric orthogonal x-rays were obtained, and prostate position was defined via 3 gold markers for each patient in the 3 axes. To achieve and confirm our action level threshold, an average of 2 x-rays sets (median 2; range, 0-4) was taken daily for each patient. Based on our ALT, we made no corrections in 8.7% (range, 0%-54%), 1 correction in 82% (41%-98%), and 2 to 3 corrections in 9% (0-27%). No patient needed 4 or more corrections. All patients were treated with a confirmed error of < 2.5 mm for every beam delivered. After all corrections, the mean and standard deviations were: anterior-posterior (z): 0.003 +/- 0.094 cm; superior-inferior (y): 0.028 +/- 0.073 cm; and right-left (x) -0.013 +/- 0.08 cm. It is feasible to limit all final prostate positions to less than 2.5 mm employing an action level image-guided radiation therapy (IGRT) process. The residual errors after corrections were very small.

  3. Gray/White Matter Contrast in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Carme Uribe

    2018-03-01

    Full Text Available Gray/white matter contrast (GWC decreases with aging and has been found to be a useful MRI biomarker in Alzheimer’s disease (AD, but its utility in Parkinson’s disease (PD patients has not been investigated. The aims of the study were to test whether GWC is sensitive to aging changes in PD patients, if PD patients differ from healthy controls (HCs in GWC, and whether the use of GWC data would improve the sensitivity of cortical thickness analyses to differentiate PD patients from controls. Using T1-weighted structural images, we obtained individual cortical thickness and GWC values from a sample of 90 PD patients and 27 controls. Images were processed with the automated FreeSurfer stream. GWC was computed by dividing the white matter (WM by the gray matter (GM values and projecting the ratios onto a common surface. The sample characteristics were: 52 patients and 14 controls were males; mean age of 64.4 ± 10.6 years in PD and 64.7 ± 8.6 years in controls; 8.0 ± 5.6 years of disease evolution; 15.6 ± 9.8 UPDRS; and a range of 1.5–3 in Hoehn and Yahr (H&Y stage. In both PD and controls we observed significant correlations between GWC and age involving almost the entire cortex. When applying a stringent cluster-forming threshold of p < 0.0001, the correlation between GWC and age also involved the entire cortex in the PD group; in the control group, the correlation was found in the parahippocampal gyrus and widespread frontal and parietal areas. The GWC of PD patients did not differ from controls’, whereas cortical thickness analyses showed thinning in temporal and parietal cortices in the PD group. Cortical thinning remained unchanged after adjusting for GWC. GWC is a very sensitive measure for detecting aging effects, but did not provide additional information over other parameters of atrophy in PD.

  4. A Symmetric Chaos-Based Image Cipher with an Improved Bit-Level Permutation Strategy

    Directory of Open Access Journals (Sweden)

    Chong Fu

    2014-02-01

    Full Text Available Very recently, several chaos-based image ciphers using a bit-level permutation have been suggested and shown promising results. Due to the diffusion effect introduced in the permutation stage, the workload of the time-consuming diffusion stage is reduced, and hence the performance of the cryptosystem is improved. In this paper, a symmetric chaos-based image cipher with a 3D cat map-based spatial bit-level permutation strategy is proposed. Compared with those recently proposed bit-level permutation methods, the diffusion effect of the new method is superior as the bits are shuffled among different bit-planes rather than within the same bit-plane. Moreover, the diffusion key stream extracted from hyperchaotic system is related to both the secret key and the plain image, which enhances the security against known/chosen plaintext attack. Extensive security analysis has been performed on the proposed scheme, including the most important ones like key space analysis, key sensitivity analysis, plaintext sensitivity analysis and various statistical analyses, which has demonstrated the satisfactory security of the proposed scheme

  5. A 256×256 low-light-level CMOS imaging sensor with digital CDS

    Science.gov (United States)

    Zou, Mei; Chen, Nan; Zhong, Shengyou; Li, Zhengfen; Zhang, Jicun; Yao, Li-bin

    2016-10-01

    In order to achieve high sensitivity for low-light-level CMOS image sensors (CIS), a capacitive transimpedance amplifier (CTIA) pixel circuit with a small integration capacitor is used. As the pixel and the column area are highly constrained, it is difficult to achieve analog correlated double sampling (CDS) to remove the noise for low-light-level CIS. So a digital CDS is adopted, which realizes the subtraction algorithm between the reset signal and pixel signal off-chip. The pixel reset noise and part of the column fixed-pattern noise (FPN) can be greatly reduced. A 256×256 CIS with CTIA array and digital CDS is implemented in the 0.35μm CMOS technology. The chip size is 7.7mm×6.75mm, and the pixel size is 15μm×15μm with a fill factor of 20.6%. The measured pixel noise is 24LSB with digital CDS in RMS value at dark condition, which shows 7.8× reduction compared to the image sensor without digital CDS. Running at 7fps, this low-light-level CIS can capture recognizable images with the illumination down to 0.1lux.

  6. Increased rCBF in gray matter heterotopias detected by SPECT using 99mTc hexamethyl-propylenamine oxime

    International Nuclear Information System (INIS)

    Henkes, H.; Klinikum Rudolf Virchow, Berlin; Hosten, N.; Cordes, M.; Neumann, K.; Hansen, M.L.

    1991-01-01

    Imaging findings of morphology and regional cerebral blood flow in two patients suffering from epileptic seizures are presented. CT and MRI revealed heterotopic gray matter as a probable structural correlate, causing the seizure disorder. 99m Tc hexamethyl-propylenamine oxime (HM-PAO) SPECT demonstrated focally increased regional cerebral blood flow in both patients in the areas of their heterotopic lesions. Heterotopic and orthotopic gray matter seem to have similar features in terms of regional perfusion. A focally increased brain perfusion in interictal epileptic patients may indicate an underlying migration anomaly. (orig.)

  7. Global and regional associations of smaller cerebral gray and white matter volumes with gait in older people.

    Directory of Open Access Journals (Sweden)

    Michele L Callisaya

    Full Text Available BACKGROUND: Gait impairments increase with advancing age and can lead to falls and loss of independence. Brain atrophy also occurs in older age and may contribute to gait decline. We aimed to investigate global and regional relationships of cerebral gray and white matter volumes with gait speed, and its determinants step length and cadence, in older people. METHODS: In a population-based study, participants aged >60 years without Parkinson's disease or brain infarcts underwent magnetic resonance imaging and gait measurements using a computerized walkway. Linear regression was used to study associations of total gray and white matter volumes with gait, adjusting for each other, age, sex, height and white matter hyperintensity volume. Other covariates considered in analyses included weight and vascular disease history. Voxel-based morphometry was used to study regional relationships of gray and white matter with gait. RESULTS: There were 305 participants, mean age 71.4 (6.9 years, 54% male, mean gait speed 1.16 (0.22 m/s. Smaller total gray matter volume was independently associated with poorer gait speed (p = 0.001 and step length (p<0.001, but not cadence. Smaller volumes of cortical and subcortical gray matter in bilateral regions important for motor control, vision, perception and memory were independently associated with slower gait speed and shorter steps. No global or regional associations were observed between white matter volume and gait independent of gray matter volume, white matter hyperintensity volume and other covariates. CONCLUSION: Smaller gray matter volume in bilaterally distributed brain networks serving motor control was associated with slower gait speed and step length, but not cadence.

  8. Gray literature: An important resource in systematic reviews.

    Science.gov (United States)

    Paez, Arsenio

    2017-08-01

    Systematic reviews aide the analysis and dissemination of evidence, using rigorous and transparent methods to generate empirically attained answers to focused research questions. Identifying all evidence relevant to the research questions is an essential component, and challenge, of systematic reviews. Gray literature, or evidence not published in commercial publications, can make important contributions to a systematic review. Gray literature can include academic papers, including theses and dissertations, research and committee reports, government reports, conference papers, and ongoing research, among others. It may provide data not found within commercially published literature, providing an important forum for disseminating studies with null or negative results that might not otherwise be disseminated. Gray literature may thusly reduce publication bias, increase reviews' comprehensiveness and timeliness, and foster a balanced picture of available evidence. Gray literature's diverse formats and audiences can present a significant challenge in a systematic search for evidence. However, the benefits of including gray literature may far outweigh the cost in time and resource needed to search for it, and it is important for it to be included in a systematic review or review of evidence. A carefully thought out gray literature search strategy may be an invaluable component of a systematic review. This narrative review provides guidance about the benefits of including gray literature in a systematic review, and sources for searching through gray literature. An illustrative example of a search for evidence within gray literature sources is presented to highlight the potential contributions of such a search to a systematic review. Benefits and challenges of gray literature search methods are discussed, and recommendations made. © 2017 Chinese Cochrane Center, West China Hospital of Sichuan University and John Wiley & Sons Australia, Ltd.

  9. Illumination normalization of face image based on illuminant direction estimation and improved Retinex.

    Science.gov (United States)

    Yi, Jizheng; Mao, Xia; Chen, Lijiang; Xue, Yuli; Rovetta, Alberto; Caleanu, Catalin-Daniel

    2015-01-01

    Illumination normalization of face image for face recognition and facial expression recognition is one of the most frequent and difficult problems in image processing. In order to obtain a face image with normal illumination, our method firstly divides the input face image into sixteen local regions and calculates the edge level percentage in each of them. Secondly, three local regions, which meet the requirements of lower complexity and larger average gray value, are selected to calculate the final illuminant direction according to the error function between the measured intensity and the calculated intensity, and the constraint function for an infinite light source model. After knowing the final illuminant direction of the input face image, the Retinex algorithm is improved from two aspects: (1) we optimize the surround function; (2) we intercept the values in both ends of histogram of face image, determine the range of gray levels, and stretch the range of gray levels into the dynamic range of display device. Finally, we achieve illumination normalization and get the final face image. Unlike previous illumination normalization approaches, the method proposed in this paper does not require any training step or any knowledge of 3D face and reflective surface model. The experimental results using extended Yale face database B and CMU-PIE show that our method achieves better normalization effect comparing with the existing techniques.

  10. Illumination normalization of face image based on illuminant direction estimation and improved Retinex.

    Directory of Open Access Journals (Sweden)

    Jizheng Yi

    Full Text Available Illumination normalization of face image for face recognition and facial expression recognition is one of the most frequent and difficult problems in image processing. In order to obtain a face image with normal illumination, our method firstly divides the input face image into sixteen local regions and calculates the edge level percentage in each of them. Secondly, three local regions, which meet the requirements of lower complexity and larger average gray value, are selected to calculate the final illuminant direction according to the error function between the measured intensity and the calculated intensity, and the constraint function for an infinite light source model. After knowing the final illuminant direction of the input face image, the Retinex algorithm is improved from two aspects: (1 we optimize the surround function; (2 we intercept the values in both ends of histogram of face image, determine the range of gray levels, and stretch the range of gray levels into the dynamic range of display device. Finally, we achieve illumination normalization and get the final face image. Unlike previous illumination normalization approaches, the method proposed in this paper does not require any training step or any knowledge of 3D face and reflective surface model. The experimental results using extended Yale face database B and CMU-PIE show that our method achieves better normalization effect comparing with the existing techniques.

  11. Semi-automated uranium analysis by a modified Davies--Gray procedure

    International Nuclear Information System (INIS)

    Swanson, G.C.

    1977-01-01

    To rapidly and reliably determine uranium in fuel materials a semi-automated implementation of the Davies-Gray uranium titration was developed. The Davies-Gray method is essentially a three step procedure. First uranium is reduced quantitatively from +6 valence to +4 valence by excess of iron (II) in strong phosphoric acid in the absence of nitrite. Prior to the uranium reduction nitrite is destroyed by addition of sulfamic acid. In the second step iron (II) is selectively oxidized to iron (III) by nitric acid in the presence of Mo (VI) catalyst. Finally after dilution to reduce phosphate concentration, the uranium is titrated to U (VI) by standard dichromate. The original sluggish colorimetric endpoint determination used by Davies and Gray is seldom used since New Brunswick Laboratory discovered that addition of vanadium (IV) just prior to titration sufficiently improves reaction rate to allow a potentiometric endpoint determination. One of the advantages of the Davies-Gray uranium titration is that it is quite specific for uranium, most common impurity elements do not interfere with the analysis, and specifically high levels of Pu, Th, and Fe are tolerated

  12. Gray Matter Volume Decrease Distinguishes Schizophrenia From Bipolar Offspring During Childhood and Adolescence.

    Science.gov (United States)

    Sugranyes, Gisela; de la Serna, Elena; Romero, Soledad; Sanchez-Gistau, Vanessa; Calvo, Anna; Moreno, Dolores; Baeza, Inmaculada; Diaz-Caneja, Covadonga M; Sanchez-Gutierrez, Teresa; Janssen, Joost; Bargallo, Nuria; Castro-Fornieles, Josefina

    2015-08-01

    There is increasing support toward the notion that schizophrenia and bipolar disorder share neurodevelopmental underpinnings, although areas of divergence remain. We set out to examine gray matter volume characteristics of child and adolescent offspring of patients with schizophrenia or bipolar disorder comparatively. In this 2-center study, magnetic resonance structural neuroimaging data were acquired in 198 children and adolescents (aged 6-17 years): 38 offspring of patients with schizophrenia, 77 offspring of patients with bipolar disorder, and 83 offspring of community controls. Analyses of global brain volumes and voxel-based morphometry (using familywise error correction) were conducted. There was an effect of group on total cerebral gray matter volume (F = 3.26, p = .041), driven by a decrease in offspring of patients with schizophrenia relative to offspring of controls (p = .035). At a voxel-based level, we observed an effect of group in the left inferior frontal cortex/anterior insula (F = 14.7, p bipolar disorder (p bipolar disorder and offspring of controls in either global or voxel-based gray matter volumes. This first comparative study between offspring of patients with schizophrenia and bipolar disorder suggests that gray matter volume reduction in childhood and adolescence may be specific to offspring of patients with schizophrenia; this may index a greater neurodevelopmental impact of risk for schizophrenia relative to bipolar disorder during youth. Copyright © 2015 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  13. Application of digital image processing to a β-gauge for determining mass concentration of suspending particulate matter in atmosphere

    International Nuclear Information System (INIS)

    Gotoh, Takao

    1992-01-01

    A two-dimensional image of the mass concentration of suspending particulate matter (SPM) collected on Millipore filter paper was photographed with Ultrofilm- 3 H. The printed paper image was transformed into a digital image (256 x 256 pixels) with 256 gray levels. Two results were obtained. The averaged values of gray level over all pixels of the digital image was found to correlate with the mass value measured by a β-gauge. The characteristic range of the digital image which was transformed to frequency by two-dimensional fast fourier transformation was found in the low frequency. It was presumed to relate to SPM from anthropogenic sources because the SPMs usually show higher density and smaller particle size than SPMs from natural sources. (author)

  14. Obesity Associated Cerebral Gray and White Matter Alterations Are Interrelated in the Female Brain.

    Directory of Open Access Journals (Sweden)

    Karsten Mueller

    Full Text Available Obesity is known to affect the brain's gray matter (GM and white matter (WM structure but the interrelationship of such changes remains unclear. Here we used T1-weighted magnetic resonance imaging (MRI in combination with voxel-based morphometry (VBM and diffusion-tensor imaging (DTI with tract-based spatial statistics (TBSS to assess the relationship between obesity-associated alterations of gray matter density (GMD and anisotropic water diffusion in WM, respectively. In a small cohort of lean to obese women, we confirmed previous reports of obesity-associated alterations of GMD in brain regions involved in executive control (i.e., dorsolateral prefrontal cortex, DLPFC and habit learning (i.e., dorsal striatum. Gray matter density alterations of the DLPFC were negatively correlated with radial diffusivity in the entire corpus callosum. Within the genu of the corpus callosum we found a positive correlation with axial diffusivity. In posterior region and inferior areas of the body of the corpus callosum, axial diffusivity correlated negatively with altered GMD in the dorsal striatum. These findings suggest that, in women, obesity-related alterations of GMD in brain regions involved in executive control and habit learning might relate to alterations of associated WM fiber bundles within the corpus callosum.

  15. Differentiating benign from malignant bone tumors using fluid-fluid level features on magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hong; Cui, Jian Ling; Cui, Sheng Jie; Sun, Ying Cal; Cui, Feng Zhen [Dept. of Radiology, The Third Hospital of Hebei Medical University, Hebei Province Biomechanical Key Laborary of Orthopedics, Shijiazhuang, Hebei (China)

    2014-12-15

    To analyze different fluid-fluid level features between benign and malignant bone tumors on magnetic resonance imaging (MRI). This study was approved by the hospital ethics committee. We retrospectively analyzed 47 patients diagnosed with benign (n = 29) or malignant (n = 18) bone tumors demonstrated by biopsy/surgical resection and who showed the intratumoral fluid-fluid level on pre-surgical MRI. The maximum length of the largest fluid-fluid level and the ratio of the maximum length of the largest fluid-fluid level to the maximum length of a bone tumor in the sagittal plane were investigated for use in distinguishing benign from malignant tumors using the Mann-Whitney U-test and a receiver operating characteristic (ROC) analysis. Fluid-fluid level was categorized by quantity (multiple vs. single fluid-fluid level) and by T1-weighted image signal pattern (high/low, low/high, and undifferentiated), and the findings were compared between the benign and malignant groups using the chi2 test. The ratio of the maximum length of the largest fluid-fluid level to the maximum length of bone tumors in the sagittal plane that allowed statistically significant differentiation between benign and malignant bone tumors had an area under the ROC curve of 0.758 (95% confidence interval, 0.616-0.899). A cutoff value of 41.5% (higher value suggests a benign tumor) had sensitivity of 73% and specificity of 83%. The ratio of the maximum length of the largest fluid-fluid level to the maximum length of a bone tumor in the sagittal plane may be useful to differentiate benign from malignant bone tumors.

  16. Differentiating benign from malignant bone tumors using fluid-fluid level features on magnetic resonance imaging

    International Nuclear Information System (INIS)

    Yu, Hong; Cui, Jian Ling; Cui, Sheng Jie; Sun, Ying Cal; Cui, Feng Zhen

    2014-01-01

    To analyze different fluid-fluid level features between benign and malignant bone tumors on magnetic resonance imaging (MRI). This study was approved by the hospital ethics committee. We retrospectively analyzed 47 patients diagnosed with benign (n = 29) or malignant (n = 18) bone tumors demonstrated by biopsy/surgical resection and who showed the intratumoral fluid-fluid level on pre-surgical MRI. The maximum length of the largest fluid-fluid level and the ratio of the maximum length of the largest fluid-fluid level to the maximum length of a bone tumor in the sagittal plane were investigated for use in distinguishing benign from malignant tumors using the Mann-Whitney U-test and a receiver operating characteristic (ROC) analysis. Fluid-fluid level was categorized by quantity (multiple vs. single fluid-fluid level) and by T1-weighted image signal pattern (high/low, low/high, and undifferentiated), and the findings were compared between the benign and malignant groups using the chi2 test. The ratio of the maximum length of the largest fluid-fluid level to the maximum length of bone tumors in the sagittal plane that allowed statistically significant differentiation between benign and malignant bone tumors had an area under the ROC curve of 0.758 (95% confidence interval, 0.616-0.899). A cutoff value of 41.5% (higher value suggests a benign tumor) had sensitivity of 73% and specificity of 83%. The ratio of the maximum length of the largest fluid-fluid level to the maximum length of a bone tumor in the sagittal plane may be useful to differentiate benign from malignant bone tumors.

  17. IMAGE ANALYSIS BASED ON EDGE DETECTION TECHNIQUES

    Institute of Scientific and Technical Information of China (English)

    纳瑟; 刘重庆

    2002-01-01

    A method that incorporates edge detection technique, Markov Random field (MRF), watershed segmentation and merging techniques was presented for performing image segmentation and edge detection tasks. It first applies edge detection technique to obtain a Difference In Strength (DIS) map. An initial segmented result is obtained based on K-means clustering technique and the minimum distance. Then the region process is modeled by MRF to obtain an image that contains different intensity regions. The gradient values are calculated and then the watershed technique is used. DIS calculation is used for each pixel to define all the edges (weak or strong) in the image. The DIS map is obtained. This help as priority knowledge to know the possibility of the region segmentation by the next step (MRF), which gives an image that has all the edges and regions information. In MRF model,gray level l, at pixel location i, in an image X, depends on the gray levels of neighboring pixels. The segmentation results are improved by using watershed algorithm. After all pixels of the segmented regions are processed, a map of primitive region with edges is generated. The edge map is obtained using a merge process based on averaged intensity mean values. A common edge detectors that work on (MRF) segmented image are used and the results are compared. The segmentation and edge detection result is one closed boundary per actual region in the image.

  18. Differentiating Patients with Parkinson's Disease from Normal Controls Using Gray Matter in the Cerebellum.

    Science.gov (United States)

    Zeng, Ling-Li; Xie, Liang; Shen, Hui; Luo, Zhiguo; Fang, Peng; Hou, Yanan; Tang, Beisha; Wu, Tao; Hu, Dewen

    2017-02-01

    Parkinson's disease (PD) is one of the most common neurodegenerative disorders in the world. Previous studies have focused on the basal ganglia and cerebral cortices. To date, the cerebellum has not been systematically investigated in patients with PD. In the current study, 45 probable PD patients and 40 age- and gender-matched healthy controls underwent structural magnetic resonance imaging, and we used support vector machines combining with voxel-based morphometry to explore the cerebellar structural changes in the probable PD patients relative to healthy controls. The results revealed that the gray matter alterations were primarily located within the cerebellar Crus I, implying a possible important role of this region in PD. Furthermore, the gray matter alterations in the cerebellum could differentiate the probable PD patients from healthy controls with accuracies of more than 95 % (p cerebellum in the clinical diagnosis of PD.

  19. Effect of Experimental Thyrotoxicosis on Brain Gray Matter: A Voxel-Based Morphometry Study.

    Science.gov (United States)

    Göbel, Anna; Heldmann, Marcus; Göttlich, Martin; Dirk, Anna-Luise; Brabant, Georg; Münte, Thomas F

    2015-09-01

    Hyper-as well hypothyroidism have an effect on behavior and brain function. Moreover, during development thyroid hormones influence brain structure. This study aimed to demonstrate an effect of experimentally induced hyperthyroidism on brain gray matter in healthy adult humans. High-resolution 3D T1-weighted images were acquired in 29 healthy young subjects prior to as well as after receiving 250 µg of T4 per day for 8 weeks. Voxel-based morphometry analysis was performed using Statistical Parametric Mapping 8 (SPM8). Laboratory testing confirmed the induction of hyperthyroidism. In the hyperthyroid condition, gray matter volumes were increased in the right posterior cerebellum (lobule VI) and decreased in the bilateral visual cortex and anterior cerebellum (lobules I-IV) compared to the euthyroid condition. Our study provides evidence that short periods of hyperthyroidism induce distinct alterations in brain structures of cerebellar regions that have been associated with sensorimotor functions as well as working memory in the literature.

  20. Thresholding: A Pixel-Level Image Processing Methodology Preprocessing Technique for an OCR System for the Brahmi Script

    Directory of Open Access Journals (Sweden)

    H. K. Anasuya Devi

    2006-12-01

    Full Text Available In this paper we study the methodology employed for preprocessing the archaeological images. We present the various algorithms used in the low-level processing stage of image analysis for Optical Character Recognition System for Brahmi Script. The image preprocessing technique covered in this paper is thresholding. We also try to analyze the results obtained by the pixel-level processing algorithms.

  1. The association of cognitive impairment with gray matter atrophy and cortical lesion load in clinically isolated syndrome.

    Science.gov (United States)

    Diker, Sevda; Has, Arzu Ceylan; Kurne, Aslı; Göçmen, Rahşan; Oğuz, Kader Karlı; Karabudak, Rana

    2016-11-01

    Multiple sclerosis can impair cognition from the early stages and has been shown to be associated with gray matter damage in addition to white matter pathology. To investigate the profile of cognitive impairment in clinically isolated syndrome (CIS), and the contribution of cortical inflammation, cortical and deep gray matter atrophy, and white matter lesions to cognitive decline. Thirty patients with clinically isolated syndrome and twenty demographically- matched healthy controls underwent neuropsychologic assessment through the Rao Brief Repeatable Battery, and brain magnetic resonance imaging with double inversion recovery using a 3T scanner. Patients with clinically isolated syndrome performed significantly worse than healthy controls on tests that evaluated verbal memory, visuospatial learning and memory, and verbal fluency. Significant deep gray matter atrophy was found in the patients but cortical volume was not lower than the controls. Visual memory tests correlated with the volume of the hippocampus, cerebral white matter and deep gray matter structures and with cerebellar cortical atrophy. Cortical or white matter lesion load did not affect cognitive test results. In our patients with CIS, it was shown that cognitive impairment was mainly related to cerebral white matter, cerebellar cortical and deep gray matter atrophy, but not with cortical inflammation, at least in the early stage of disease. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. A methodology for the extraction of quantitative information from electron microscopy images at the atomic level

    International Nuclear Information System (INIS)

    Galindo, P L; Pizarro, J; Guerrero, E; Guerrero-Lebrero, M P; Scavello, G; Yáñez, A; Sales, D L; Herrera, M; Molina, S I; Núñez-Moraleda, B M; Maestre, J M

    2014-01-01

    In this paper we describe a methodology developed at the University of Cadiz (Spain) in the past few years for the extraction of quantitative information from electron microscopy images at the atomic level. This work is based on a coordinated and synergic activity of several research groups that have been working together over the last decade in two different and complementary fields: Materials Science and Computer Science. The aim of our joint research has been to develop innovative high-performance computing techniques and simulation methods in order to address computationally challenging problems in the analysis, modelling and simulation of materials at the atomic scale, providing significant advances with respect to existing techniques. The methodology involves several fundamental areas of research including the analysis of high resolution electron microscopy images, materials modelling, image simulation and 3D reconstruction using quantitative information from experimental images. These techniques for the analysis, modelling and simulation allow optimizing the control and functionality of devices developed using materials under study, and have been tested using data obtained from experimental samples

  3. Natural products in Glycyrrhiza glabra (licorice) rhizome imaged at the cellular level by atmospheric pressure matrix-assisted laser desorption/ionization tandem mass spectrometry imaging

    DEFF Research Database (Denmark)

    Li, Bin; Bhandari, Dhaka Ram; Janfelt, Christian

    2014-01-01

    The rhizome of Glycyrrhiza glabra (licorice) was analyzed by high-resolution mass spectrometry imaging and tandem mass spectrometry imaging. An atmospheric pressure matrix-assisted laser desorption/ionization imaging ion source was combined with an orbital trapping mass spectrometer in order to o...... and saponins in legume species, combing the spatially resolved chemical information with morphological details at the microscopic level. Furthermore, the technique offers a scheme capable of high-throughput profiling of metabolites in plant tissues....

  4. Prediction of myelopathic level in cervical spondylotic myelopathy using diffusion tensor imaging.

    Science.gov (United States)

    Wang, Shu-Qiang; Li, Xiang; Cui, Jiao-Long; Li, Han-Xiong; Luk, Keith D K; Hu, Yong

    2015-06-01

    To investigate the use of a newly designed machine learning-based classifier in the automatic identification of myelopathic levels in cervical spondylotic myelopathy (CSM). In all, 58 normal volunteers and 16 subjects with CSM were recruited for diffusion tensor imaging (DTI) acquisition. The eigenvalues were extracted as the selected features from DTI images. Three classifiers, naive Bayesian, support vector machine, and support tensor machine, and fractional anisotropy (FA) were employed to identify myelopathic levels. The results were compared with clinical level diagnosis results and accuracy, sensitivity, and specificity were calculated to evaluate the performance of the developed classifiers. The accuracy by support tensor machine was the highest (93.62%) among the three classifiers. The support tensor machine also showed excellent capacity to identify true positives (sensitivity: 84.62%) and true negatives (specificity: 97.06%). The accuracy by FA value was the lowest (76%) in all the methods. The classifiers-based method using eigenvalues had a better performance in identifying the levels of CSM than the diagnosis using FA values. The support tensor machine was the best among three classifiers. © 2014 Wiley Periodicals, Inc.

  5. Geophysical Imaging of Sea-level Proxies in Beach-Ridge Deposits

    Science.gov (United States)

    Nielsen, L.; Emerich Souza, P.; Meldgaard, A.; Bendixen, M.; Kroon, A.; Clemmensen, L. B.

    2017-12-01

    We show ground-penetrating radar (GPR) reflection data collected over modern and fossil beach deposits from different localities along coastlines in meso-tidal regimes of Greenland and micro-tidal regimes of Denmark. The acquired reflection GPR sections show several similar characteristics but also some differences. A similar characteristic is the presence of downlapping reflections, where the downlap point is interpreted to mark the transition from upper shoreface to beachface deposits and, thus, be a marker of a level close to or at sea-level at the time of deposition. Differences in grain size of the investigated beach ridge system result in different scattering characteristics of the acquired GPR data. These differences call for tailored, careful processing of the GPR data for optimal imaging of internal beach ridge architecture. We outline elements of the GPR data processing of particular importance for optimal imaging. Moreover, we discuss advantages and challenges related to using GPR-based proxies of sea-level as compared to other methods traditionally used for establishment of curves of past sea-level variation.

  6. Detection of pre-symptomatic rose powdery-mildew and gray-mold diseases based on thermal vision

    Science.gov (United States)

    Jafari, M.; Minaei, S.; Safaie, N.

    2017-09-01

    Roses are the most important plants in ornamental horticulture. Roses are susceptible to a number of phytopathogenic diseases. Among the most serious diseases of rose, powdery mildew (Podosphaera pannosa var. rosae) and gray mold (Botrytis cinerea) are widespread which require considerable attention. In this study, the potential of implementing thermal imaging to detect the pre-symptomatic appearance of these fungal diseases was investigated. Effects of powdery mildew and gray mold diseases on rose plants (Rosa hybrida L.) were examined by two experiments conducted in a growth chamber. To classify the healthy and infected plants, feature selection was carried out and the best extracted thermal features with the largest linguistic hedge values were chosen. Two neuro-fuzzy classifiers were trained to distinguish between the healthy and infected plants. Best estimation rates of 92.55% and 92.3% were achieved in training and testing the classifier with 8 clusters in order to identify the leaves infected with powdery mildew. In addition, the best estimation rates of 97.5% and 92.59% were achieved in training and testing the classifier with 4 clusters to identify the gray mold disease on flowers. Performance of the designed neuro-fuzzy classifiers were evaluated with the thermal images captured using an automatic imaging setup. Best correct estimation rates of 69% and 80% were achieved (on the second day post-inoculation) for pre-symptomatic appearance detection of powdery mildew and gray mold diseases, respectively.

  7. Multimodal imaging of the human knee down to the cellular level

    Science.gov (United States)

    Schulz, G.; Götz, C.; Müller-Gerbl, M.; Zanette, I.; Zdora, M.-C.; Khimchenko, A.; Deyhle, H.; Thalmann, P.; Müller, B.

    2017-06-01

    Computed tomography reaches the best spatial resolution for the three-dimensional visualization of human tissues among the available nondestructive clinical imaging techniques. Nowadays, sub-millimeter voxel sizes are regularly obtained. Regarding investigations on true micrometer level, lab-based micro-CT (μCT) has become gold standard. The aim of the present study is firstly the hierarchical investigation of a human knee post mortem using hard X-ray μCT and secondly a multimodal imaging using absorption and phase contrast modes in order to investigate hard (bone) and soft (cartilage) tissues on the cellular level. After the visualization of the entire knee using a clinical CT, a hierarchical imaging study was performed using the lab-system nanotom® m. First, the entire knee was measured with a pixel length of 65 μm. The highest resolution with a pixel length of 3 μm could be achieved after extracting cylindrically shaped plugs from the femoral bones. For the visualization of the cartilage, grating-based phase contrast μCT (I13-2, Diamond Light Source) was performed. With an effective voxel size of 2.3 μm it was possible to visualize individual chondrocytes within the cartilage.

  8. Multi-level discriminative dictionary learning with application to large scale image classification.

    Science.gov (United States)

    Shen, Li; Sun, Gang; Huang, Qingming; Wang, Shuhui; Lin, Zhouchen; Wu, Enhua

    2015-10-01

    The sparse coding technique has shown flexibility and capability in image representation and analysis. It is a powerful tool in many visual applications. Some recent work has shown that incorporating the properties of task (such as discrimination for classification task) into dictionary learning is effective for improving the accuracy. However, the traditional supervised dictionary learning methods suffer from high computation complexity when dealing with large number of categories, making them less satisfactory in large scale applications. In this paper, we propose a novel multi-level discriminative dictionary learning method and apply it to large scale image classification. Our method takes advantage of hierarchical category correlation to encode multi-level discriminative information. Each internal node of the category hierarchy is associated with a discriminative dictionary and a classification model. The dictionaries at different layers are learnt to capture the information of different scales. Moreover, each node at lower layers also inherits the dictionary of its parent, so that the categories at lower layers can be described with multi-scale information. The learning of dictionaries and associated classification models is jointly conducted by minimizing an overall tree loss. The experimental results on challenging data sets demonstrate that our approach achieves excellent accuracy and competitive computation cost compared with other sparse coding methods for large scale image classification.

  9. Low episodic memory performance in cognitively normal elderly subjects is associated with increased posterior cingulate gray matter N-acetylaspartate: a 1H MRSI study at 7 Tesla.

    Science.gov (United States)

    Schreiner, Simon J; Kirchner, Thomas; Wyss, Michael; Van Bergen, Jiri M G; Quevenco, Frances C; Steininger, Stefanie C; Griffith, Erica Y; Meier, Irene; Michels, Lars; Gietl, Anton F; Leh, Sandra E; Brickman, Adam M; Hock, Christoph; Nitsch, Roger M; Pruessmann, Klaas P; Henning, Anke; Unschuld, Paul G

    2016-12-01

    Low episodic memory performance characterizes elderly subjects at increased risk for Alzheimer's disease (AD) and may reflect neuronal dysfunction within the posterior cingulate cortex and precuneus (PCP) region. To investigate a potential association between cerebral neurometabolism and low episodic memory in the absence of cognitive impairment, tissue-specific magnetic resonance spectroscopic imaging at ultrahigh field strength of 7 Tesla was used to investigate the PCP region in a healthy elderly study population (n = 30, age 70 ± 5.7 years, Mini-Mental State Examination 29.4 ± 4.1). The Verbal Learning and Memory Test (VLMT) was administered as part of a neuropsychological battery for assessment of episodic memory performance. Significant differences between PCP gray and white matter could be observed for glutamate-glutamine (p = 0.001), choline (p = 0.01), and myo-inositol (p = 0.02). Low Verbal Learning and Memory Test performance was associated with high N-acetylaspartate in PCP gray matter (p = 0.01) but not in PCP white matter. Our data suggest that subtle decreases in episodic memory performance in the elderly may be associated with increased levels of N-acetylaspartate as a reflection of increased mitochondrial energy capacity in PCP gray matter. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Reducing surgical levels by paraspinal mapping and diffusion tensor imaging techniques in lumbar spinal stenosis.

    Science.gov (United States)

    Chen, Hua-Biao; Wan, Qi; Xu, Qi-Feng; Chen, Yi; Bai, Bo

    2016-04-25

    Correlating symptoms and physical examination findings with surgical levels based on common imaging results is not reliable. In patients who have no concordance between radiological and clinical symptoms, the surgical levels determined by conventional magnetic resonance imaging (MRI) and neurogenic examination (NE) may lead to a more extensive surgery and significant complications. We aimed to confirm that whether the use of diffusion tensor imaging (DTI) and paraspinal mapping (PM) techniques can further prevent the occurrence of false positives with conventional MRI, distinguish which are clinically relevant from levels of cauda equina and/or nerve root lesions based on MRI, and determine and reduce the decompression levels of lumbar spinal stenosis than MRI + NE, while ensuring or improving surgical outcomes. We compared the data between patients who underwent MRI + (PM or DTI) and patients who underwent conventional MRI + NE to determine levels of decompression for the treatment of lumbar spinal stenosis. Outcome measures were assessed at 2 weeks, 3 months, 6 months, and 12 months postoperatively. One hundred fourteen patients (59 in the control group, 54 in the experimental group) underwent decompression. The levels of decompression determined by MRI + (PM or DTI) in the experimental group were significantly less than that determined by MRI + NE in the control group (p = 0.000). The surgical time, blood loss, and surgical transfusion were significantly less in the experimental group (p = 0.001, p = 0.011, p = 0.001, respectively). There were no differences in improvement of the visual analog scale back and leg pain (VAS-BP, VAS-LP) scores and Oswestry Disability Index (ODI) scores at 2 weeks, 3 months, 6 months, and 12 months after operation between the experimental and control groups. MRI + (PM or DTI) showed clear benefits in determining decompression levels of lumbar spinal stenosis than MRI + NE. In patients with lumbar spinal

  11. Efficient OCT Image Enhancement Based on Collaborative Shock Filtering.

    Science.gov (United States)

    Liu, Guohua; Wang, Ziyu; Mu, Guoying; Li, Peijin

    2018-01-01

    Efficient enhancement of noisy optical coherence tomography (OCT) images is a key task for interpreting them correctly. In this paper, to better enhance details and layered structures of a human retina image, we propose a collaborative shock filtering for OCT image denoising and enhancement. Noisy OCT image is first denoised by a collaborative filtering method with new similarity measure, and then the denoised image is sharpened by a shock-type filtering for edge and detail enhancement. For dim OCT images, in order to improve image contrast for the detection of tiny lesions, a gamma transformation is first used to enhance the images within proper gray levels. The proposed method integrating image smoothing and sharpening simultaneously obtains better visual results in experiments.

  12. Gray matter abnormalities in patients with narcissistic personality disorder.

    Science.gov (United States)

    Schulze, Lars; Dziobek, Isabel; Vater, Aline; Heekeren, Hauke R; Bajbouj, Malek; Renneberg, Babette; Heuser, Isabella; Roepke, Stefan

    2013-10-01

    Despite the relevance of narcissistic personality disorder (NPD) in clinical settings, there is currently no empirical data available regarding the neurobiological correlates of NPD. In the present study, we performed a voxel-based morphometric analysis to provide initial insight into local abnormalities of gray matter (GM) volume. Structural brain images were obtained from patients with NPD (n = 17) and a sample of healthy controls (n = 17) matched regarding age, gender, handedness, and intelligence. Groups were compared with regard to global brain tissue volumes and local abnormalities of GM volume. Regions-of-interest analyses were calculated for the anterior insula. Relative to the control group, NPD patients had smaller GM volume in the left anterior insula. Independent of group, GM volume in the left anterior insula was positively related to self-reported emotional empathy. Complementary whole-brain analyses yielded smaller GM volume in fronto-paralimbic brain regions comprising the rostral and median cingulate cortex as well as dorsolateral and medial parts of the prefrontal cortex. Here we provide the first empirical evidence for structural abnormalities in fronto-paralimbic brain regions of patients with NPD. The results are discussed in the context of NPD patients' restricted ability for emotional empathy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. 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.

  14. Simultaneous measurement of particle velocity and size based on gray difference and autocorrelation

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The gray of two images of a same particle taken by a digital camera with different exposure times is different too. Based on the gray difference of particle images in a double-exposed photo and autocorrelation processing of digital images,this paper proposes a method for measuring particle velocities and sizes simultaneously. This paper also introduces the theoretical foundation of this method,the process of particle imaging and image processing,and the simultaneous measurement of velocity and size of a low speed flow field with 35 μm and 75 μm standard particles. The graphical measurement results can really reflect the flow characteristics of the flow field. In addition,although the measured velocity and size histograms of these two kinds of standard particles are slightly wider than the theoretical ones,they are all still similar to the normal distribution,and the peak velocities and diameters of the histograms are consistent with the default values. Therefore,this measurement method is capable of providing moderate measurement accuracy,and it can be further developed for high-speed flow field measurements.

  15. High-level core sample x-ray imaging at the Hanford Site

    International Nuclear Information System (INIS)

    Weber, J.R.; Keve, J.K.

    1995-10-01

    Waste tank sampling of radioactive high-level waste is required for continued operations, waste characterization, and site safety. Hanford Site tank farms consist of 28 double-shell and 149 single-shell underground storage tanks. The single shell tanks are out-of-service an no longer receive liquid waste. Core samples of salt cake and sludge waste are remotely obtained using truck-mounted, core drill platforms. Samples are recovered from tanks through a 2.25 inch (in.) drill pipe in 26-in. steel tubes, 1.5 in. diameter. Drilling parameters vary with different waste types. Because sample recovery has been marginal an inadequate at times, a system was needed to provide drill truck operators with ''real-time feedback'' about the physical condition of the sample and the percent recovery, prior to making nuclear assay measurements and characterizations at the analytical laboratory. The Westinghouse Hanford Company conducted proof-of-principal radiographic testing to verify the feasibility of a proposed imaging system. Tests were conducted using an iridium 192 radiography source to determine the effects of high radiation on image quality. The tests concluded that samplers with a dose rate in excess of 5000 R/hr could be imaged with only a slight loss of image quality and samples less than 1000 R/hr have virtually no effect on image quality. The Mobile Core Sample X-Ray Examination System, a portable vendor-engineered assembly, has components uniquely configured to produce a real-time radiographic system suitable for safely examining radioactive tank core segments collected at the Hanford Site. The radiographic region of interest extends from the bottom (valve) of the sampler upward 19 to 20 in. The purpose of the Mobile Core Sample X-Ray Examination System is to examine the physical contents of core samples after removal from the tank and prior to placement in an onsite transfer cask

  16. Potential ungulate prey for Gray Wolves

    Science.gov (United States)

    Singer, Francis J.; Mack, John A.

    1993-01-01

    Data were gathered for six ungulate species that reside in or near Yellowstone National Park. If gray wolves (Canis lupus) are reintroduced into the Yellowstone area, their avoidance of human activities or their management by human may determine their range. Therefore, the area of wolf occupation cannot be predicted now. We restricted our analysis to Yellowstone National Park and to the adjacent national forest wilderness areas. We included mostly ungulate herds that summer inside or adjacent to the park and that would probably be affected by wolves. Our wolf study area includes Yellowstone National Park and adjacent wilderness areas most likely to be occupied by wolves. We reviewed publications, park records, survey reports, and state fish and game surveys and reports for statistics on ungulate populations. These data [provide an overview of ungulate populations and harvests. Each ungulate herd is described in detail. We restricted our analysis to 1980-89, because population surveys were more complete during that period and because population estimates of most ungulate populations had increased by the 1980's. We feel the higher estimates of the 1980's reflect more up-to-date techniques and are most representative of the situation into which the wolves would be reintroduced.

  17. Black and gray Helmholtz-Kerr soliton refraction

    International Nuclear Information System (INIS)

    Sanchez-Curto, Julio; Chamorro-Posada, Pedro; McDonald, Graham S.

    2011-01-01

    Refraction of black and gray solitons at boundaries separating different defocusing Kerr media is analyzed within a Helmholtz framework. A universal nonlinear Snell's law is derived that describes gray soliton refraction, in addition to capturing the behavior of bright and black Kerr solitons at interfaces. Key regimes, defined by beam and interface characteristics, are identified, and predictions are verified by full numerical simulations. The existence of a unique total nonrefraction angle for gray solitons is reported; both internal and external refraction at a single interface is shown possible (dependent only on incidence angle). This, in turn, leads to the proposal of positive or negative lensing operations on soliton arrays at planar boundaries.

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

    International Nuclear Information System (INIS)

    Kang, Hye Jin; Lee, Ho Young; Lee, Jae Sung; Kang, Eun Joo; Lee, Sang Gun; Chang, Kee Hyun; Lee, Dong Soo

    2004-01-01

    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

  19. 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.

  20. Study of system for segmentation of images and elaboration of algorithms for three dimensional scene reconstruction

    International Nuclear Information System (INIS)

    Bufacchi, A.; Tripi, A.

    1995-09-01

    The aim of this paper is the presentation of a series of methodologies to recognize and to obtain a three-dimensional reconstruction of an inner architectural scene, using a gray level image obtained using a TV camera. In the first part of the work, a series of methods used to find the edges in an effective way are critically compared, obtaining a binary image, and then the application of the Hough transform to such binary image to find the straight lines in the original image are discussed. In the second part, an algorithm is shown in order to find the vanishing points in such image

  1. Shape in Picture: Mathematical Description of Shape in Grey-Level Images

    Science.gov (United States)

    1992-09-11

    following diagram commutes: A N FGA fl______ IFg B FGB rB Define Gjrff g; it is routine (an exercise) to show that G is a functor. [3 Jetu IL- to Cat ...Heijmans, H.J.A.M., Dougherty, E.R. (1992). Gray-scale granulome - tries compatible with spatial scalings, CWI Report BS-R9212, Amsterdam. 16...sensorimotor cortex of cat . Consider the archetypal pyramidal neuron of Fig. 3. The classical view is that afferent volleys synapse upon the dendrites

  2. Automatic segmentation of MRI head images by 3-D region growing method which utilizes edge information

    International Nuclear Information System (INIS)

    Jiang, Hao; Suzuki, Hidetomo; Toriwaki, Jun-ichiro

    1991-01-01

    This paper presents a 3-D segmentation method that automatically extracts soft tissue from multi-sliced MRI head images. MRI produces a sequence of two-dimensional (2-D) images which contains three-dimensional (3-D) information of organs. To utilize such information we need effective algorithms to treat 3-D digital images and to extract organs and tissues of interest. We developed a method to extract the brain from MRI images which uses a region growing procedure and integrates information of uniformity of gray levels and information of the presence of edge segments in the local area around the pixel of interest. First we generate a kernel region which is a part of brain tissue by simple thresholding. Then we grow the region by means of a region growing algorithm under the control of 3-D edge existence to obtain the region of the brain. Our method is rather simple because it uses basic 3-D image processing techniques like spatial difference. It is robust for variation of gray levels inside a tissue since it also refers to the edge information in the process of region growing. Therefore, the method is flexible enough to be applicable to the segmentation of other images including soft tissues which have complicated shapes and fluctuation in gray levels. (author)

  3. Level of conus medullaris termination in adult population analyzed by kinetic magnetic resonance imaging.

    Science.gov (United States)

    Liu, An; Yang, Kaixiang; Wang, Daling; Li, Changqing; Ren, Zhiwei; Yan, Shigui; Buser, Zorica; Wang, Jeffrey C

    2017-07-01

    To investigate the change of conus medullaris termination (CMT) level in neutral, flexion and extension positions and to analyze the effects of age and gender on the CMT level. The midline sagittal T2-weighted kinetic magnetic resonance imaging (kMRI) study of 585 patients was retrospectively reviewed to identify the level of CMT. All patients were in an upright position. A straight line perpendicular to the long axis of the cord was drawn from the tip of the cord and then subtended to the adjacent vertebra or disk space. The CMT level was labeled in relation to the upper, middle and lower segments of adjacent vertebra or disk space and assigned values from 0 to 12 [0 = upper third of T12 (T12U), and 12 = upper third of L3 (L3U)]. All parameters were collected for neutral, flexion and extension positions. The level of CMT had the highest incidence (17.61%) at L1 lower (L1L) in neutral position, 17.44% at L1 upper (L1U) in flexion, and 16.92% at L1 middle (L1M) in extension with no significant differences among three positions (p > 0.05) in weight-bearing status. Moreover, the level of CMT was not correlated with age (p > 0.05). In terms of gender, the level of CMT was lower in women than in men in neutral position, flexion, and extension (p level of CMT in the neutral position was in accordance with previous cadaveric and supine-position MRI studies, and it did not change with flexion and extension. Women had lower CMT level than men, especially in the older population. This information can be very valuable when performing spinal anesthesia and spinal punctures.

  4. Microwave imaging of dielectric cylinder using level set method and conjugate gradient algorithm

    International Nuclear Information System (INIS)

    Grayaa, K.; Bouzidi, A.; Aguili, T.

    2011-01-01

    In this paper, we propose a computational method for microwave imaging cylinder and dielectric object, based on combining level set technique and the conjugate gradient algorithm. By measuring the scattered field, we tried to retrieve the shape, localisation and the permittivity of the object. The forward problem is solved by the moment method, while the inverse problem is reformulate in an optimization one and is solved by the proposed scheme. It found that the proposed method is able to give good reconstruction quality in terms of the reconstructed shape and permittivity.

  5. Computerized image analysis: estimation of breast density on mammograms

    Science.gov (United States)

    Zhou, Chuan; Chan, Heang-Ping; Petrick, Nicholas; Sahiner, Berkman; Helvie, Mark A.; Roubidoux, Marilyn A.; Hadjiiski, Lubomir M.; Goodsitt, Mitchell M.

    2000-06-01

    An automated image analysis tool is being developed for estimation of mammographic breast density, which may be useful for risk estimation or for monitoring breast density change in a prevention or intervention program. A mammogram is digitized using a laser scanner and the resolution is reduced to a pixel size of 0.8 mm X 0.8 mm. Breast density analysis is performed in three stages. First, the breast region is segmented from the surrounding background by an automated breast boundary-tracking algorithm. Second, an adaptive dynamic range compression technique is applied to the breast image to reduce the range of the gray level distribution in the low frequency background and to enhance the differences in the characteristic features of the gray level histogram for breasts of different densities. Third, rule-based classification is used to classify the breast images into several classes according to the characteristic features of their gray level histogram. For each image, a gray level threshold is automatically determined to segment the dense tissue from the breast region. The area of segmented dense tissue as a percentage of the breast area is then estimated. In this preliminary study, we analyzed the interobserver variation of breast density estimation by two experienced radiologists using BI-RADS lexicon. The radiologists' visually estimated percent breast densities were compared with the computer's calculation. The results demonstrate the feasibility of estimating mammographic breast density using computer vision techniques and its potential to improve the accuracy and reproducibility in comparison with the subjective visual assessment by radiologists.

  6. Gray matter perfusion correlates with disease severity in ALS.

    Science.gov (United States)

    Rule, Randall R; Schuff, Norbert; Miller, Robert G; Weiner, Michael W

    2010-03-09

    The goal of this study is to determine if regional brain perfusion, as measured by arterial spin labeling (ASL) MRI, is correlated with clinical measures of amyotrophic lateral sclerosis (ALS) disease severity. The presence of such a relationship would indicate a possible role for ASL perfusion as a marker of disease severity and upper motor neuron involvement in ALS. Disease severity was assessed in 16 subjects with ALS (age 54 +/- 11) using the Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS) and the pulmonary function measure, forced vital capacity (FVC). Upper motor neuron involvement was assessed by testing rapid tapping of the fingers and feet. Magnetic resonance perfusion images were coregistered with structural T1-weighted MRI, corrected for partial volume effects using the structural images and normalized to a study-specific atlas. Correlations between perfusion and ALS disease severity were analyzed, using statistical parametric mapping, and including age as a factor. Analyses were adjusted for multiple clusters. ALS severity, as measured by the ALSFRS and FVC, was correlated with gray matter perfusion. This correlation was predominantly observed in the hemisphere contralateral to the more affected limbs. ALSFRS scores correlated with perfusion in the contralateral frontal and parietal lobe (p frontal lobe (p frontal lobe (p Upper motor neuron involvement, as measured by rapid finger tapping, correlated bilaterally with perfusion in the middle cingulate gyrus (p < 0.001). Amyotrophic lateral sclerosis (ALS) severity is correlated with brain perfusion as measured by arterial spin labeling (ASL) perfusion. This correlation appears to be independent of brain atrophy. ASL perfusion may be a useful tool for monitoring disease progression and assessing treatment effects in ALS.

  7. Automatic Fontanel Extraction from Newborns' CT Images Using Variational Level Set

    Science.gov (United States)

    Kazemi, Kamran; Ghadimi, Sona; Lyaghat, Alireza; Tarighati, Alla; Golshaeyan, Narjes; Abrishami-Moghaddam, Hamid; Grebe, Reinhard; Gondary-Jouet, Catherine; Wallois, Fabrice

    A realistic head model is needed for source localization methods used for the study of epilepsy in neonates applying Electroencephalographic (EEG) measurements from the scalp. The earliest models consider the head as a series of concentric spheres, each layer corresponding to a different tissue whose conductivity is assumed to be homogeneous. The results of the source reconstruction depend highly on the electric conductivities of the tissues forming the head.The most used model is constituted of three layers (scalp, skull, and intracranial). Most of the major bones of the neonates’ skull are ossified at birth but can slightly move relative to each other. This is due to the sutures, fibrous membranes that at this stage of development connect the already ossified flat bones of the neurocranium. These weak parts of the neurocranium are called fontanels. Thus it is important to enter the exact geometry of fontaneles and flat bone in a source reconstruction because they show pronounced in conductivity. Computer Tomography (CT) imaging provides an excellent tool for non-invasive investigation of the skull which expresses itself in high contrast to all other tissues while the fontanels only can be identified as absence of bone, gaps in the skull formed by flat bone. Therefore, the aim of this paper is to extract the fontanels from CT images applying a variational level set method. We applied the proposed method to CT-images of five different subjects. The automatically extracted fontanels show good agreement with the manually extracted ones.

  8. Long-term in vivo imaging of multiple organs at the single cell level.

    Directory of Open Access Journals (Sweden)

    Benny J Chen

    Full Text Available Two-photon microscopy has enabled the study of individual cell behavior in live animals. Many organs and tissues cannot be studied, especially longitudinally, because they are located too deep, behind bony structures or too close to the lung and heart. Here we report a novel mouse model that allows long-term single cell imaging of many organs. A wide variety of live tissues were successfully engrafted in the pinna of the mouse ear. Many of these engrafted tissues maintained the normal tissue histology. Using the heart and thymus as models, we further demonstrated that the engrafted tissues functioned as would be expected. Combining two-photon microscopy with fluorescent tracers, we successfully visualized the engrafted tissues at the single cell level in live mice over several months. Four dimensional (three-dimensional (3D plus time information of individual cells was obtained from this imaging. This model makes long-term high resolution 4D imaging of multiple organs possible.

  9. Robust algebraic image enhancement for intelligent control systems

    Science.gov (United States)

    Lerner, Bao-Ting; Morrelli, Michael

    1993-01-01

    Robust vision capability for intelligent control systems has been an elusive goal in image processing. The computationally intensive techniques a necessary for conventional image processing make real-time applications, such as object tracking and collision avoidance difficult. In order to endow an intelligent control system with the needed vision robustness, an adequate image enhancement subsystem capable of compensating for the wide variety of real-world degradations, must exist between the image capturing and the object recognition subsystems. This enhancement stage must be adaptive and must operate with consistency in the presence of both statistical and shape-based noise. To deal with this problem, we have developed an innovative algebraic approach which provides a sound mathematical framework for image representation and manipulation. Our image model provides a natural platform from which to pursue dynamic scene analysis, and its incorporation into a vision system would serve as the front-end to an intelligent control system. We have developed a unique polynomial representation of gray level imagery and applied this representation to develop polynomial operators on complex gray level scenes. This approach is highly advantageous since polynomials can be manipulated very easily, and are readily understood, thus providing a very convenient environment for image processing. Our model presents a highly structured and compact algebraic representation of grey-level images which can be viewed as fuzzy sets.

  10. A 1,000 Frames/s Programmable Vision Chip with Variable Resolution and Row-Pixel-Mixed Parallel Image Processors

    Directory of Open Access Journals (Sweden)

    Nanjian Wu

    2009-07-01

    Full Text Available A programmable vision chip with variable resolution and row-pixel-mixed parallel image processors is presented. The chip consists of a CMOS sensor array, with row-parallel 6-bit Algorithmic ADCs, row-parallel gray-scale image processors, pixel-parallel SIMD Processing Element (PE array, and instruction controller. The resolution of the image in the chip is variable: high resolution for a focused area and low resolution for general view. It implements gray-scale and binary mathematical morphology algorithms in series to carry out low-level and mid-level image processing and sends out features of the image for various applications. It can perform image processing at over 1,000 frames/s (fps. A prototype chip with 64 × 64 pixels resolution and 6-bit gray-scale image is fabricated in 0.18 mm Standard CMOS process. The area size of chip is 1.5 mm × 3.5 mm. Each pixel size is 9.5 μm × 9.5 μm and each processing element size is 23 μm × 29 μm. The experiment results demonstrate that the chip can perform low-level and mid-level image processing and it can be applied in the real-time vision applications, such as high speed target tracking.

  11. Comparison of Cox and Gray's survival models in severe sepsis

    DEFF Research Database (Denmark)

    Kasal, Jan; Andersen, Zorana Jovanovic; Clermont, Gilles

    2004-01-01

    Although survival is traditionally modeled using Cox proportional hazards modeling, this approach may be inappropriate in sepsis, in which the proportional hazards assumption does not hold. Newer, more flexible models, such as Gray's model, may be more appropriate....

  12. Severe maxillary osteomyelitis in a Gray Wolf (Canis lupus)

    Science.gov (United States)

    Barber-Meyer, Shannon

    2012-01-01

    Dental injuries to or abnormalities in functionally important teeth and associated bones in predators may significantly reduce the ability to kill and consume prey (Lazar et al. 2009). This impairment is likely exacerbated in coursing predators, such as Gray Wolves, that bite and hold onto fleeing and kicking prey with their teeth. Damage to carnassials (upper fourth premolar, P4, and lower first molar, M1) and associated bones in Gray Wolves may especially inhibit the consumption of prey because these teeth slice meat and crush bone. Here I report maxillary osteomyelitis involving the carnassials in a wild Gray Wolf from northeastern Minnesota of such severity that I hypothesize it ultimately caused the Gray Wolf to starve to death.

  13. Toward accurate tooth segmentation from computed tomography images using a hybrid level set model

    Energy Technology Data Exchange (ETDEWEB)

    Gan, Yangzhou; Zhao, Qunfei [Department of Automation, Shanghai Jiao Tong University, and Key Laboratory of System Control and Information Processing, Ministry of Education of China, Shanghai 200240 (China); Xia, Zeyang, E-mail: zy.xia@siat.ac.cn, E-mail: jing.xiong@siat.ac.cn; Hu, Ying [Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, and The Chinese University of Hong Kong, Shenzhen 518055 (China); Xiong, Jing, E-mail: zy.xia@siat.ac.cn, E-mail: jing.xiong@siat.ac.cn [Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 510855 (China); Zhang, Jianwei [TAMS, Department of Informatics, University of Hamburg, Hamburg 22527 (Germany)

    2015-01-15

    Purpose: A three-dimensional (3D) model of the teeth provides important information for orthodontic diagnosis and treatment planning. Tooth segmentation is an essential step in generating the 3D digital model from computed tomography (CT) images. The aim of this study is to develop an accurate and efficient tooth segmentation method from CT images. Methods: The 3D dental CT volumetric images are segmented slice by slice in a two-dimensional (2D) transverse plane. The 2D segmentation is composed of a manual initialization step and an automatic slice by slice segmentation step. In the manual initialization step, the user manually picks a starting slice and selects a seed point for each tooth in this slice. In the automatic slice segmentation step, a developed hybrid level set model is applied to segment tooth contours from each slice. Tooth contour propagation strategy is employed to initialize the level set function automatically. Cone beam CT (CBCT) images of two subjects were used to tune the parameters. Images of 16 additional subjects were used to validate the performance of the method. Volume overlap metrics and surface distance metrics were adopted to assess the segmentation accuracy quantitatively. The volume overlap metrics were volume difference (VD, mm{sup 3}) and Dice similarity coefficient (DSC, %). The surface distance metrics were average symmetric surface distance (ASSD, mm), RMS (root mean square) symmetric surface distance (RMSSSD, mm), and maximum symmetric surface distance (MSSD, mm). Computation time was recorded to assess the efficiency. The performance of the proposed method has been compared with two state-of-the-art methods. Results: For the tested CBCT images, the VD, DSC, ASSD, RMSSSD, and MSSD for the incisor were 38.16 ± 12.94 mm{sup 3}, 88.82 ± 2.14%, 0.29 ± 0.03 mm, 0.32 ± 0.08 mm, and 1.25 ± 0.58 mm, respectively; the VD, DSC, ASSD, RMSSSD, and MSSD for the canine were 49.12 ± 9.33 mm{sup 3}, 91.57 ± 0.82%, 0.27 ± 0.02 mm, 0

  14. Toward accurate tooth segmentation from computed tomography images using a hybrid level set model

    International Nuclear Information System (INIS)

    Gan, Yangzhou; Zhao, Qunfei; Xia, Zeyang; Hu, Ying; Xiong, Jing; Zhang, Jianwei

    2015-01-01

    Purpose: A three-dimensional (3D) model of the teeth provides important information for orthodontic diagnosis and treatment planning. Tooth segmentation is an essential step in generating the 3D digital model from computed tomography (CT) images. The aim of this study is to develop an accurate and efficient tooth segmentation method from CT images. Methods: The 3D dental CT volumetric images are segmented slice by slice in a two-dimensional (2D) transverse plane. The 2D segmentation is composed of a manual initialization step and an automatic slice by slice segmentation step. In the manual initialization step, the user manually picks a starting slice and selects a seed point for each tooth in this slice. In the automatic slice segmentation step, a developed hybrid level set model is applied to segment tooth contours from each slice. Tooth contour propagation strategy is employed to initialize the level set function automatically. Cone beam CT (CBCT) images of two subjects were used to tune the parameters. Images of 16 additional subjects were used to validate the performance of the method. Volume overlap metrics and surface distance metrics were adopted to assess the segmentation accuracy quantitatively. The volume overlap metrics were volume difference (VD, mm 3 ) and Dice similarity coefficient (DSC, %). The surface distance metrics were average symmetric surface distance (ASSD, mm), RMS (root mean square) symmetric surface distance (RMSSSD, mm), and maximum symmetric surface distance (MSSD, mm). Computation time was recorded to assess the efficiency. The performance of the proposed method has been compared with two state-of-the-art methods. Results: For the tested CBCT images, the VD, DSC, ASSD, RMSSSD, and MSSD for the incisor were 38.16 ± 12.94 mm 3 , 88.82 ± 2.14%, 0.29 ± 0.03 mm, 0.32 ± 0.08 mm, and 1.25 ± 0.58 mm, respectively; the VD, DSC, ASSD, RMSSSD, and MSSD for the canine were 49.12 ± 9.33 mm 3 , 91.57 ± 0.82%, 0.27 ± 0.02 mm, 0.28 ± 0.03 mm

  15. FDG-PET imaging of lower extremity muscular activity during level walking

    International Nuclear Information System (INIS)

    Oi, Naoyuki; Iwaya, Tsutomu; Tobimatsu, Yoshiko; Fujimoto, Toshihiko; Itoh, Masatoshi; Yamaguchi, Keiichiro

    2003-01-01

    We analyzed muscular activity of the lower extremities during level walking using positron emission tomography (PET) with 18 F-fluorodeoxyglucose ( 18 F-FDG). We examined 17 healthy male subjects; 11 were assigned to a walking group and 6 to a resting group. After 18 F-FDG injection, the walking group subjects walked at a free speed for 15 min. A whole-body image was then obtained by a PET camera, and the standardized uptake ratio (SUR) was computed for each muscle. The SUR for each muscle of the walking group was compared with that for the corresponding muscles in the resting group. The level of muscular activity of all the muscles we examined were higher during level walking than when resting. The activity of the lower leg muscles was higher than that of the thigh muscles during level walking. The muscular activity of the soleus was highest among all the muscles examined. Among the gluteal muscles, the muscular activity of the gluteus minimus was higher than that of the gluteus maximus and gluteus medius. The concurrent validity of measuring muscular activity of the lower extremity during level walking by the PET method using 18 F-FDG was demonstrated. (author)

  16. Brain MR imaging in dietarily treated phenylketonuria

    Energy Technology Data Exchange (ETDEWEB)

    Breysem, L. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Smet, M.H. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Johannik, K. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Hecke, P. van [Dept. of Radiology, University Hospitals, Leuven (Belgium); Francois, B. [L. Willems Inst., Diepenbeek (Belgium); Wilms, G. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Bosmans, H. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Marchal, G. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Jaeken, J. [Dept. of Pediatrics, University Hospitals, Leuven (Belgium); Demaerel, P. [Dept. of Radiology, University Hospitals, Leuven (Belgium)

    1994-08-01

    Magnetic resonance imaging is the most efficient imaging modality to evaluate brain gray and white matter of patients with metabolic diseases. The main purpose of our study was to investigate the relation between brain MRI abnormalities and the phenylalanine (phe) and tyrosine (tyr) blood levels in 38 phenylketonuria (PKU) patients. Increased periventricular white matter intensity on T2-weighted brain images was the only pathologic finding in 24 patients. Brain MRI abnormalities were scored (4) and correlated with the individual mean phe and phe/tyr levels during 1 year preceding MR examination and with phe tolerance. The residual activity of phenylalanine hydroxylase was defined for each patient by an oral phe tolerance. The appearance of MRI abnormalities on brain T2-weighted images correlates with a threshold mean phe level (averaged over the year preceding the examination). (orig.)

  17. Brain MR imaging in dietarily treated phenylketonuria

    International Nuclear Information System (INIS)

    Breysem, L.; Smet, M.H.; Johannik, K.; Hecke, P. van; Francois, B.; Wilms, G.; Bosmans, H.; Marchal, G.; Jaeken, J.; Demaerel, P.

    1994-01-01

    Magnetic resonance imaging is the most efficient imaging modality to evaluate brain gray and white matter of patients with metabolic diseases. The main purpose of our study was to investigate the relation between brain MRI abnormalities and the phenylalanine (phe) and tyrosine (tyr) blood levels in 38 phenylketonuria (PKU) patients. Increased periventricular white matter intensity on T2-weighted brain images was the only pathologic finding in 24 patients. Brain MRI abnormalities were scored (4) and correlated with the individual mean phe and phe/tyr levels during 1 year preceding MR examination and with phe tolerance. The residual activity of phenylalanine hydroxylase was defined for each patient by an oral phe tolerance. The appearance of MRI abnormalities on brain T2-weighted images correlates with a threshold mean phe level (averaged over the year preceding the examination). (orig.)

  18. Methods of Blood Oxygen Level-Dependent Magnetic Resonance Imaging Analysis for Evaluating Renal Oxygenation

    Directory of Open Access Journals (Sweden)

    Fen Chen

    2018-03-01

    Full Text Available Blood oxygen level-dependent magnetic resonance imaging (BOLD MRI has recently been utilized as a noninvasive tool for evaluating renal oxygenation. Several methods have been proposed for analyzing BOLD images. Regional ROI selection is the earliest and most widely used method for BOLD analysis. In the last 20 years, many investigators have used this method to evaluate cortical and medullary oxygenation in patients with ischemic nephropathy, hypertensive nephropathy, diabetic nephropathy, chronic kidney disease (CKD, acute kidney injury and renal allograft rejection. However, clinical trials of BOLD MRI using regional ROI selection revealed that it was difficult to distinguish the renal cortico-medullary zones with this method, and that it was susceptible to observer variability. To overcome these deficiencies, several new methods were proposed for analyzing BOLD images, including the compartmental approach, fractional hypoxia method, concentric objects (CO method and twelve-layer concentric objects (TLCO method. The compartmental approach provides an algorithm to judge whether the pixel belongs to the cortex or medulla. Fractional kidney hypoxia, measured by using BOLD MRI, was negatively correlated with renal blood flow, tissue perfusion and glomerular filtration rate (GFR in patients with atherosclerotic renal artery stenosis. The CO method divides the renal parenchyma into six or twelve layers of thickness in each coronal slice of BOLD images and provides a R2* radial profile curve. The slope of the R2* curve associated positively with eGFR in CKD patients. Indeed, each method invariably has advantages and disadvantages, and there is generally no consensus method so far. Undoubtedly, analytic approaches for BOLD MRI with better reproducibility would assist clinicians in monitoring the degree of kidney hypoxia and thus facilitating timely reversal of tissue hypoxia.

  19. GABA levels in the ventromedial prefrontal cortex during the viewing of appetitive and disgusting food images.

    Science.gov (United States)

    Padulo, Caterina; Delli Pizzi, Stefano; Bonanni, Laura; Edden, Richard A E; Ferretti, Antonio; Marzoli, Daniele; Franciotti, Raffaella; Manippa, Valerio; Onofrj, Marco; Sepede, Gianna; Tartaro, Armando; Tommasi, Luca; Puglisi-Allegra, Stefano; Brancucci, Alfredo

    2016-10-01

    Characterizing how the brain appraises the psychological dimensions of reward is one of the central topics of neuroscience. It has become clear that dopamine neurons are implicated in the transmission of both rewarding information and aversive and alerting events through two different neuronal populations involved in encoding the motivational value and the motivational salience of stimuli, respectively. Nonetheless, there is less agreement on the role of the ventromedial prefrontal cortex (vmPFC) and the related neurotransmitter release during the processing of biologically relevant stimuli. To address this issue, we employed magnetic resonance spectroscopy (MRS), a non-invasive methodology that allows detection of some metabolites in the human brain in vivo, in order to assess the role of the vmPFC in encoding stimulus value rather than stimulus salience. Specifically, we measured gamma-aminobutyric acid (GABA) and, with control purposes, Glx levels in healthy subjects during the observation of appetitive and disgusting food images. We observed a decrease of GABA and no changes in Glx concentration in the vmPFC in both conditions. Furthermore, a comparatively smaller GABA reduction during the observation of appetitive food images than during the observation of disgusting food images was positively correlated with the scores obtained to the body image concerns sub-scale of Body Uneasiness Test (BUT). These results are consistent with the idea that the vmPFC plays a crucial role in processing both rewarding and aversive stimuli, possibly by encoding stimulus salience through glutamatergic and/or noradrenergic projections to deeper mesencephalic and limbic areas. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  20. TVR-DART: A More Robust Algorithm for Discrete Tomography From Limited Projection Data With Automated Gray Value Estimation.

    Science.gov (United States)

    Xiaodong Zhuge; Palenstijn, Willem Jan; Batenburg, Kees Joost

    2016-01-01

    In this paper, we present a novel iterative reconstruction algorithm for discrete tomography (DT) named total variation regularized discrete algebraic reconstruction technique (TVR-DART) with automated gray value estimation. This algorithm is more robust and automated than the original DART algorithm, and is aimed at imaging of objects consisting of only a few different material compositions, each corresponding to a different gray value in the reconstruction. By exploiting two types of prior knowledge of the scanned object simultaneously, TVR-DART solves the discrete reconstruction problem within an optimization framework inspired by compressive sensing to steer the current reconstruction toward a solution with the specified number of discrete gray values. The gray values and the thresholds are estimated as the reconstruction improves through iterations. Extensive experiments from simulated data, experimental μCT, and electron tomography data sets show that TVR-DART is capable of providing more accurate reconstruction than existing algorithms under noisy conditions from a small number of projection images and/or from a small angular range. Furthermore, the new algorithm requires less effort on parameter tuning compared with the original DART algorithm. With TVR-DART, we aim to provide the tomography society with an easy-to-use and robust algorithm for DT.

  1. A Weighted Two-Level Bregman Method with Dictionary Updating for Nonconvex MR Image Reconstruction

    Directory of Open Access Journals (Sweden)

    Qiegen Liu

    2014-01-01

    Full Text Available Nonconvex optimization has shown that it needs substantially fewer measurements than l1 minimization for exact recovery under fixed transform/overcomplete dictionary. In this work, two efficient numerical algorithms which are unified by the method named weighted two-level Bregman method with dictionary updating (WTBMDU are proposed for solving lp optimization under the dictionary learning model and subjecting the fidelity to the partial measurements. By incorporating the iteratively reweighted norm into the two-level Bregman iteration method with dictionary updating scheme (TBMDU, the modified alternating direction method (ADM solves the model of pursuing the approximated lp-norm penalty efficiently. Specifically, the algorithms converge after a relatively small number of iterations, under the formulation of iteratively reweighted l1 and l2 minimization. Experimental results on MR image simulations and real MR data, under a variety of sampling trajectories and acceleration factors, consistently demonstrate that the proposed method can efficiently reconstruct MR images from highly undersampled k-space data and presents advantages over the current state-of-the-art reconstruction approaches, in terms of higher PSNR and lower HFEN values.

  2. Automated tracking of lava lake level using thermal images at Kīlauea Volcano, Hawai’i

    Science.gov (United States)

    Patrick, Matthew R.; Swanson, Don; Orr, Tim R.

    2016-01-01

    Tracking the level of the lava lake in Halema‘uma‘u Crater, at the summit of Kīlauea Volcano, Hawai’i, is an essential part of monitoring the ongoing eruption and forecasting potentially hazardous changes in activity. We describe a simple automated image processing routine that analyzes continuously-acquired thermal images of the lava lake and measures lava level. The method uses three image segmentation approaches, based on edge detection, short-term change analysis, and composite temperature thresholding, to identify and track the lake margin in the images. These relative measurements from the images are periodically calibrated with laser rangefinder measurements to produce real-time estimates of lake elevation. Continuous, automated tracking of the lava level has been an important tool used by the U.S. Geological Survey’s Hawaiian Volcano Observatory since 2012 in real-time operational monitoring of the volcano and its hazard potential.

  3. Intrinsic gray-matter connectivity of the brain in adults with autism spectrum disorder.

    Science.gov (United States)

    Ecker, Christine; Ronan, Lisa; Feng, Yue; Daly, Eileen; Murphy, Clodagh; Ginestet, Cedric E; Brammer, Michael; Fletcher, Paul C; Bullmore, Edward T; Suckling, John; Baron-Cohen, Simon; Williams, Steve; Loth, Eva; Murphy, Declan G M

    2013-08-06

    Autism spectrum disorders (ASD) are a group of neurodevelopmental conditions that are accompanied by atypical brain connectivity. So far, in vivo evidence for atypical structural brain connectivity in ASD has mainly been based on neuroimaging studies of cortical white matter. However, genetic studies suggest that abnormal connectivity in ASD may also affect neural connections within the cortical gray matter. Such intrinsic gray-matter connections are inherently more difficult to describe in vivo but may be inferred from a variety of surface-based geometric features that can be measured using magnetic resonance imaging. Here, we present a neuroimaging study that examines the intrinsic cortico-cortical connectivity of the brain in ASD using measures of "cortical separation distances" to assess the global and local intrinsic "wiring costs" of the cortex (i.e., estimated length of horizontal connections required to wire the cortex within the cortical sheet). In a sample of 68 adults with ASD and matched controls, we observed significantly reduced intrinsic wiring costs of cortex in ASD, both globally and locally. Differences in global and local wiring cost were predominantly observed in fronto-temporal regions and also significantly predicted the severity of social and repetitive symptoms (respectively). Our study confirms that atypical cortico-cortical "connectivity" in ASD is not restricted to the development of white-matter connections but may also affect the intrinsic gray-matter architecture (and connectivity) within the cortical sheet. Thus, the atypical connectivity of the brain in ASD is complex, affecting both gray and white matter, and forms part of the core neural substrates underlying autistic symptoms.

  4. A New Approach for Deep Gray Matter Analysis Using Partial-Volume Estimation.

    Science.gov (United States)

    Bonnier, Guillaume; Kober, Tobias; Schluep, Myriam; Du Pasquier, Renaud; Krueger, Gunnar; Meuli, Reto; Granziera, Cristina; Roche, Alexis

    2016-01-01

    The existence of partial volume effects in brain MR images makes it challenging to understand physio-pathological alterations underlying signal changes due to pathology across groups of healthy subjects and patients. In this study, we implement a new approach to disentangle gray and white matter alterations in the thalamus and the basal ganglia. The proposed method was applied to a cohort of early multiple sclerosis (MS) patients and healthy subjects to evaluate tissue-specific alterations related to diffuse inflammatory or neurodegenerative processes. Forty-three relapsing-remitting MS patients and nineteen healthy controls underwent 3T MRI including: (i) fluid-attenuated inversion recovery, double inversion recovery, magnetization-prepared gradient echo for lesion count, and (ii) T1 relaxometry. We applied a partial volume estimation algorithm to T1 relaxometry maps to gray and white matter local concentrations as well as T1 values characteristic of gray and white matter in the thalamus and the basal ganglia. Statistical tests were performed to compare groups in terms of both global T1 values, tissue characteristic T1 values, and tissue concentrations. Significant increases in global T1 values were observed in the thalamus (p = 0.038) and the putamen (p = 0.026) in RRMS patients compared to HC. In the Thalamus, the T1 increase was associated with a significant increase in gray matter characteristic T1 (p = 0.0016) with no significant effect in white matter. The presented methodology provides additional information to standard MR signal averaging approaches that holds promise to identify the presence and nature of diffuse pathology in neuro-inflammatory and neurodegenerative diseases.

  5. Style and non-style in anatomical illustration: From Renaissance Humanism to Henry Gray.

    Science.gov (United States)

    Kemp, Martin

    2010-02-01

    Style is a familiar category for the analysis of art. It is less so in the history of anatomical illustration. The great Renaissance and Baroque picture books of anatomy illustrated with stylish woodcuts and engravings, such as those by Charles Estienne, Andreas Vesalius and Govard Bidloo, showed figures in dramatic action in keeping with philosophical and theological ideas about human nature. Parallels can be found in paintings of the period, such as those by Titian, Michelangelo and Hans Baldung Grien. The anatomists also claimed to portray the body in an objective manner, and showed themselves as heroes of the discovery of human knowledge. Rembrandt's painting of Dr Nicholas Tulp is the best-known image of the anatomist as hero. The British empirical tradition in the 18th century saw William Cheselden and William Hunter working with techniques of representation that were intended to guarantee detailed realism. The ambition to portray forms life-size led to massive volumes, such as those by Antonio Mascagni. John Bell, the Scottish anatomist, criticized the size and pretensions of the earlier books and argued for a plain style adapted to the needs of teaching and surgery. Henry Gray's famous Anatomy of 1858, illustrated by Henry Vandyke Carter, aspired to a simple descriptive mode of functional representation that avoided stylishness, resulting in a style of its own. Successive editions of Gray progressively saw the replacement of Gray's method and of all his illustrations. The 150th anniversary edition, edited by Susan Standring, radically re-thinks the role of Gray's book within the teaching of medicine.

  6. Progressive gray matter reduction of the superior temporal gyrus during transition to psychosis.

    Science.gov (United States)

    Takahashi, Tsutomu; Wood, Stephen J; Yung, Alison R; Soulsby, Bridget; McGorry, Patrick D; Suzuki, Michio; Kawasaki, Yasuhiro; Phillips, Lisa J; Velakoulis, Dennis; Pantelis, Christos

    2009-04-01

    Longitudinal magnetic resonance imaging studies have shown progressive gray matter reduction in the superior temporal gyrus during the earliest phases of schizophrenia. It is unknown whether these progressive processes predate the onset of psychosis. To examine gray matter reduction of the superior temporal gyrus over time in individuals at risk for psychosis and in patients with first-episode psychosis. Cross-sectional and longitudinal comparisons. Personal Assessment and Crisis Evaluation Clinic and Early Psychosis Preventions and Intervention Centre. Thirty-five ultrahigh-risk individuals (of whom 12 later developed psychosis [UHRP] and 23 did not [UHRNP]), 23 patients with first-episode psychosis (FEP), and 22 control subjects recruited from the community. Volumes of superior temporal subregions (planum polare, Heschl gyrus, planum temporale, and rostral and caudal regions) were measured at baseline and follow-up (mean, 1.8 years) and were compared across groups. In cross-sectional comparisons, only the FEP group had significantly smaller planum temporale and caudal superior temporal gyrus than other groups at baseline, whereas male UHRP subjects also had a smaller planum temporale than controls at follow-up. In longitudinal comparison, UHRP and FEP patients showed significant gray matter reduction (approximately 2%-6% per year) in the planum polare, planum temporale, and caudal region compared with controls and/or UHRNP subjects. The FEP patients also exhibited progressive gray matter loss in the left Heschl gyrus (3.0% per year) and rostral region (3.8% per year), which were correlated with the severity of delusions at follow-up. A progressive process in the superior temporal gyrus precedes the first expression of florid psychosis. These findings have important implications for underlying neurobiologic features of emerging psychotic disorders and emphasize the importance of early intervention during or before the first episode of psychosis.

  7. AD-1 with research pilot Richard E. Gray

    Science.gov (United States)

    1982-01-01

    Standing in front of the AD-1 Oblique Wing research aircraft is research pilot Richard E. Gray. Richard E. Gray joined National Aeronautics and Space Administration's Johnson Space Center, Houston, Texas, in November 1978, as an aerospace research pilot. In November 1981, Dick joined the NASA's Ames-Dryden Flight Research Facility, Edwards, California, as a research pilot. Dick was a former Co-op at the NASA Flight Research Center (a previous name of the Ames-Dryden Flight Research Facility), serving as an Operations Engineer. At Ames-Dryden, Dick was a pilot for the F-14 Aileron Rudder Interconnect Program, AD-1 Oblique Wing Research Aircraft, F-8 Digital Fly-By-Wire and Pilot Induced Oscillations investigations. He also flew the F-104, T-37, and the F-15. On November 8, 1982, Gray was fatally injured in a T-37 jet aircraft while making a pilot proficiency flight. Dick graduated with a Bachelors degree in Aeronautical Engineering from San Jose State University in 1969. He joined the U.S. Navy in July 1969, becoming a Naval Aviator in January 1971, when he was assigned to F-4 Phantoms at Naval Air Station (NAS) Miramar, California. In 1972, he flew 48 combat missions in Vietnam in F-4s with VF-111 aboard the USS Coral Sea. After making a second cruise in 1973, Dick was assigned to Air Test and Evaluation Squadron Four (VX-4) at NAS Point Mugu, California, as a project pilot on various operational test and evaluation programs. In November 1978, Dick retired from the Navy and joined NASA's Johnson Space Center. At JSC Gray served as chief project pilot on the WB-57F high-altitude research projects and as the prime television chase pilot in a T-38 for the landing portion of the Space Shuttle orbital flight tests. Dick had over 3,000 hours in more than 30 types of aircraft, an airline transport rating, and 252 carrier arrested landings. He was a member of the Society of Experimental Test Pilots serving on the Board of Directors as Southwest Section Technical Adviser in

  8. Cerebral proton magnetic resonance spectroscopy demonstrates reversibility of N-acetylaspartate/creatine in gray matter after delayed encephalopathy due to carbon monoxide intoxication

    DEFF Research Database (Denmark)

    Hansen, Marco Bo; Kondziella, Daniel; Danielsen, Else Rubæk

    2014-01-01

    with cerebral proton magnetic resonance spectroscopy showed a dramatically decrease in N-acetylaspartate to total creatine ratios and elevated lactate levels in the gray matter. Subsequently, our patient received six additional sessions of hyperbaric oxygen therapy with only minimal recovery. At six...... reversal of N-acetylaspartate to total creatine ratios in gray matter has, to our knowledge, never been described before and shows that severe, initial measurements may not predict poor long-term patient outcome....

  9. Radiocesium movement in a gray rabbit brush community

    International Nuclear Information System (INIS)

    Klepper, B.; Rogers, L.E.; Hedlund, J.D.; Schreckhise, R.G.; Price, K.R.

    1978-01-01

    Gray rabbit brush, Chrysothamnus nauseosus (Compositae), is the dominant shrub on disturbed land surfaces on much of the Energy Research and Development Administration's Hanford Reservation in south-central Washington State. A stand of rabbit brush growing on an inactive liquid-waste-disposal crib was studied. Thirty percent of the shrubs showed low but detectable radiation levels in a field survey. The primary radionuclide was 137 Cs. The source of 137 Cs in shrubs was the gravel drain field in the crib, at least 2.4 m below the surface, which was the approximate maximum depth of penetration of rabbit brush taproots. Cesium-137 was observed in roots of certain rabbit brush plants, in the upper 1 cm of soil, and in litter beneath contaminated plants but was not detectable in soil samples taken at depths of 15, 50, 100, and 150 cm. Invertebrates associated with a contaminated shrub showed higher concentrations of 137 Cs than did wider-ranging species. Two of seven pocket mice trapped on the crib contaminated detectable amounts of 137 Cs

  10. Effects of canine parvovirus on gray wolves in Minnesota

    Science.gov (United States)

    Mech, L.D.; Goyal, S.M.

    1995-01-01

    Long-term effects of disease on wild animal population demography is not well documented. We studied a gray wolf (Canis lupus) population in a 2,060km2 area of Minnesota for 15 years to determine its response to canine parvovirus (CPV). The CPV had little effect (P gt 0.05) on wolf population size while epizootic during 1979-83. However, after CPV became enzootic, percentage of pups captured during summer-fall 1984-93 and changes in subsequent winter wolf numbers were each inversely related to the serological prevalence of CPV in wolves captured during July-November (r2 = 0.39 and 0.72, P = 0.05 and lt 0.01, respectively). The CPV antibody prevalence in adult wolves increased to 87% in 1993 (r2 = 0.28, P = 0.05). However, because population level remained stable, CPV-induced mortality appeared to compensate for other mortality factors such as starvation. We -predict that the winter wolf population will decline when CPV prevalence in adults consistently exceeds 76%. The CPV may become important in limiting wolf populations.

  11. Single-level dynamic spiral CT of hepatocellular carcinoma: correlation between imaging features and tumor angiogenesis

    International Nuclear Information System (INIS)

    Chen Weixia; Min Pengqiu; Song Bin; Xiao Bangliang; Liu Yan; Wang Wendong; Chen Xian; Xu Jianying

    2001-01-01

    Objective: To investigate the correlation of the enhancement imaging features of hepatocellular carcinoma (HCC) and relevant parameters revealed by single-level dynamic spiral CT scanning with tumor microvessel counting (MVC). Methods: The study included 26 histopathologically proven HCC patients. Target-slice dynamic scanning and portal venous phase scanning were performed for all patients. The time-density curves were generated with measurement of relevant parameters including: peak value (PV) and contrast enhancement ratio (CER), and the gross enhancement morphology analyzed. Histopathological slides were carefully prepared for the standard F8RA and VEGF immunohistochemical staining and tumor microvessel counting and calculation of VEGF expression percentage of tumor cells. The enhancement imaging features of HCC lesions were correlatively studied with tumor MVC and VEGF expression. Results: Peak value of HCC lesions were 7.9 to 75.2 HU, CER were 3.8% to 36.0%. MVC were 6 to 91, and the VEGF expression percentage were 32.1% to 78.3%. The PV and CER were significantly correlated with tumor tissue MVC (r = 0.508 and 0.423, P < 0.01 and 0.05 respectively). There were no correlations between PV and CER and VEGF expression percentage. Both the patterns of time-density curve and the gross enhancement morphology of HCC lesions were also correlated with tumor MVC, and reflected the distribution characteristics of tumor microvessels within HCC lesions. A close association was found between the likelihood of intrahepatic metastasis of HCC lesions with densely enhanced pseudo capsules and the presence of rich tumor microvessels within these pseudo capsules. Conclusion: The parameters and the enhancement imaging features of HCC lesions on target-slice dynamic scanning are correlated with tumor MVC, and can reflect the distribution characteristics of tumor microvessels within HCC lesions. Dynamic spiral CT scanning is a valuable means to assess the angiogenic activity and

  12. Image Denoising And Segmentation Approchto Detect Tumor From BRAINMRI Images

    Directory of Open Access Journals (Sweden)

    Shanta Rangaswamy

    2018-04-01

    Full Text Available The detection of the Brain Tumor is a challenging problem, due to the structure of the Tumor cells in the brain. This project presents a systematic method that enhances the detection of brain tumor cells and to analyze functional structures by training and classification of the samples in SVM and tumor cell segmentation of the sample using DWT algorithm. From the input MRI Images collected, first noise is removed from MRI images by applying wiener filtering technique. In image enhancement phase, all the color components of MRI Images will be converted into gray scale image and make the edges clear in the image to get better identification and improvised quality of the image. In the segmentation phase, DWT on MRI Image to segment the grey-scale image is performed. During the post-processing, classification of tumor is performed by using SVM classifier. Wiener Filter, DWT, SVM Segmentation strategies were used to find and group the tumor position in the MRI filtered picture respectively. An essential perception in this work is that multi arrange approach utilizes various leveled classification strategy which supports execution altogether. This technique diminishes the computational complexity quality in time and memory. This classification strategy works accurately on all images and have achieved the accuracy of 93%.

  13. CNNs flag recognition preprocessing scheme based on gray scale stretching and local binary pattern

    Science.gov (United States)

    Gong, Qian; Qu, Zhiyi; Hao, Kun

    2017-07-01

    Flag is a rather special recognition target in image recognition because of its non-rigid features with the location, scale and rotation characteristics. The location change can be handled well by the depth learning algorithm Convolutional Neural Networks (CNNs), but the scale and rotation changes are quite a challenge for CNNs. Since it has good rotation and gray scale invariance, the local binary pattern (LBP) is combined with grayscale stretching and CNNs to make LBP and grayscale stretching as CNNs pretreatment, which can not only significantly improve the efficiency of flag recognition, but can also evaluate the recognition effect through ROC, accuracy, MSE and quality factor.

  14. Long-term meditation is associated with increased gray matter density in the brain stem

    DEFF Research Database (Denmark)

    Vestergaard-Poulsen, Peter; Beek, Martijn van; Skewes, Joshua

    2009-01-01

    density in lower brain stem regions of experienced meditators compared with age-matched nonmeditators. Our findings show that long-term practitioners of meditation have structural differences in brainstem regions concerned with cardiorespiratory control. This could account for some......Extensive practice involving sustained attention can lead to changes in brain structure. Here, we report evidence of structural differences in the lower brainstem of participants engaged in the long-term practice of meditation. Using magnetic resonance imaging, we observed higher gray matter...

  15. Long-term meditation is associated with increased gray matter density in the brain stem

    DEFF Research Database (Denmark)

    Vestergaard-Poulsen, Peter; Beek, Martijn van; Skewes, Joshua

    2009-01-01

    Extensive practice involving sustained attention can lead to changes in brain structure. Here, we report evidence of structural differences in the lower brainstem of participants engaged in the long-term practice of meditation. Using magnetic resonance imaging, we observed higher gray matter...... density in lower brain stem regions of experienced meditators compared with age-matched nonmeditators. Our findings show that long-term practitioners of meditation have structural differences in brainstem regions concerned with cardiorespiratory control. This could account for some...... of the cardiorespiratory parasympathetic effects and traits, as well as the cognitive, emotional, and immunoreactive impact reported in several studies of different meditation practices....

  16. Determining the Level of the Dural Sac Tip: Magnetic Resonance Imaging in an Adult Population

    International Nuclear Information System (INIS)

    Binokay, F.; Akgul, E.; Bicakci, K.; Soyupak, S.; Aksungur, E.; Sertdemir, Y.

    2006-01-01

    Purpose: To determine the variation in the location of the dural sac (DS) in a living adult population and to correlate this position with age and sex. Material and Methods: T2-weighted, midline, sagittal, spin-echo magnetic resonance imaging (MRI) studies of 743 patients were assessed to identify the tip of the DS. This location was recorded in relation to the upper, middle, or lower third of the adjacent vertebral body or the adjacent intervertebral disk. Results: Frequency distribution for levels of termination of the DS on MRI demonstrated that the end of the DS was usually located at the upper one-third of S2 (25.2%). The mean level in females was also the upper one-third of S2 (26.5%) and in males the lower one-third of S2 (24.1%). The overall mean DS position was mostly at the upper one-third of S2. No significant differences in DS position were seen between male and female patients or with increasing age. Conclusion: It is important to know the possible range for the termination level of the DS when performing caudal anesthesia and craniospinal irradiation in some clinical situations. The distribution of DS location in a large adult population was shown to range from the L5-S1 intervertebral disk to the upper third of S3 vertebrae

  17. [Adaptation of self-image level and defense mechanisms in elderly patients with complicated stoma].

    Science.gov (United States)

    Ortiz-Rivas, Miriam Karina; Moreno-Pérez, Norma Elvira; Vega-Macías, Héctor Daniel; Jiménez-González, María de Jesús; Navarro-Elías, María de Guadalupe

    2014-01-01

    Ostomy patients face a number of problems that impact negatively on their personal welfare. The aim of this research is determine the nature and intensity of the relationship between the level of self-concept adaptive mode and the consistent use of coping strategies of older adults with a stoma. Quantitative, correlational and transversal. VIVEROS 03 and CAPS surveys were applied in 3 hospitals in the City of Durango, México. The study included 90 older adults with an intestinal elimination stoma with complications. Kendall's Tau-b coefficient was the non-parametric test used to measure this association. Most older adults analyzed (61.3 < % < 79.9) are not completely adapted to the condition of living with an intestinal stoma. There is also a moderate positive correlation (0,569) between the level of adaptation of the older adults with a stoma and the conscious use of coping strategies. The presence of an intestinal stoma represents a physical and psychological health problem that is reflected in the level of adaptation of the self-image. Elderly people with a stoma use only a small part of defense mechanisms as part of coping process. This limits their ability to face the adversities related to their condition, potentially causing major health complications. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  18. Computed tomography imaging with the Adaptive Statistical Iterative Reconstruction (ASIR) algorithm: dependence of image quality on the blending level of reconstruction.

    Science.gov (United States)

    Barca, Patrizio; Giannelli, Marco; Fantacci, Maria Evelina; Caramella, Davide

    2018-06-01

    Computed tomography (CT) is a useful and widely employed imaging technique, which represents the largest source of population exposure to ionizing radiation in industrialized countries. Adaptive Statistical Iterative Reconstruction (ASIR) is an iterative reconstruction algorithm with the potential to allow reduction of radiation exposure while preserving diagnostic information. The aim of this phantom study was to assess the performance of ASIR, in terms of a number of image quality indices, when different reconstruction blending levels are employed. CT images of the Catphan-504 phantom were reconstructed using conventional filtered back-projection (FBP) and ASIR with reconstruction blending levels of 20, 40, 60, 80, and 100%. Noise, noise power spectrum (NPS), contrast-to-noise ratio (CNR) and modulation transfer function (MTF) were estimated for different scanning parameters and contrast objects. Noise decreased and CNR increased non-linearly up to 50 and 100%, respectively, with increasing blending level of reconstruction. Also, ASIR has proven to modify the NPS curve shape. The MTF of ASIR reconstructed images depended on tube load/contrast and decreased with increasing blending level of reconstruction. In particular, for low radiation exposure and low contrast acquisitions, ASIR showed lower performance than FBP, in terms of spatial resolution for all blending levels of reconstruction. CT image quality varies substantially with the blending level of reconstruction. ASIR has the potential to reduce noise whilst maintaining diagnostic information in low radiation exposure CT imaging. Given the opposite variation of CNR and spatial resolution with the blending level of reconstruction, it is recommended to use an optimal value of this parameter for each specific clinical application.

  19. A Web Service for File-Level Access to Disk Images

    Directory of Open Access Journals (Sweden)

    Sunitha Misra

    2014-07-01

    Full Text Available Digital forensics tools have many potential applications in the curation of digital materials in libraries, archives and museums (LAMs. Open source digital forensics tools can help LAM professionals to extract digital contents from born-digital media and make more informed preservation decisions. Many of these tools have ways to display the metadata of the digital media, but few provide file-level access without having to mount the device or use complex command-line utilities. This paper describes a project to develop software that supports access to the contents of digital media without having to mount or download the entire image. The work examines two approaches in creating this tool: First, a graphical user interface running on a local machine. Second, a web-based application running in web browser. The project incorporates existing open source forensics tools and libraries including The Sleuth Kit and libewf along with the Flask web application framework and custom Python scripts to generate web pages supporting disk image browsing.

  20. Linear and curvilinear correlations of brain gray matter volume and density with age using voxel-based morphometry with the Akaike information criterion in 291 healthy children.

    Science.gov (United States)

    Taki, Yasuyuki; Hashizume, Hiroshi; Thyreau, Benjamin; Sassa, Yuko; Takeuchi, Hikaru; Wu, Kai; Kotozaki, Yuka; Nouchi, Rui; Asano, Michiko; Asano, Kohei; Fukuda, Hiroshi; Kawashima, Ryuta

    2013-08-01

    We examined linear and curvilinear correlations of gray matter volume and density in cortical and subcortical gray matter with age using magnetic resonance images (MRI) in a large number of healthy children. We applied voxel-based morphometry (VBM) and region-of-interest (ROI) analyses with the Akaike information criterion (AIC), which was used to determine the best-fit model by selecting which predictor terms should be included. We collected data on brain structural MRI in 291 healthy children aged 5-18 years. Structural MRI data were segmented and normalized using a custom template by applying the diffeomorphic anatomical registration using exponentiated lie algebra (DARTEL) procedure. Next, we analyzed the correlations of gray matter volume and density with age in VBM with AIC by estimating linear, quadratic, and cubic polynomial functions. Several regions such as the prefrontal cortex, the precentral gyrus, and cerebellum showed significant linear or curvilinear correlations between gray matter volume and age on an increasing trajectory, and between gray matter density and age on a decreasing trajectory in VBM and ROI analyses with AIC. Because the trajectory of gray matter volume and density with age suggests the progress of brain maturation, our results may contribute to clarifying brain maturation in healthy children from the viewpoint of brain structure. Copyright © 2012 Wiley Periodicals, Inc.

  1. Speed control of boiler feed water pump turbine based on gray correlation compensation

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yun Long; Wang, Di; Zhou, Hai Chun [Northeast Dianli UniversityJilin (China)

    2017-01-15

    One of the most important controlled parameters of thermal power units is the boiler drum water level. Disturbances of feed water flow rate could cause instability of the drum water level. This study proposes the Gray correlation compensation (GCC) control technology for the Boiler feed water pump turbine (BFPT) to solve this problem. Simulation results indicate that the GCC controller outperforms the traditional proportional-integral-derivative controller when it encounters different disturbances. Furthermore, the GCC controller can rapidly switch to the high-pressure steam source to ensure that the drum water level is in the secure range during steam source switching of the BFPT.

  2. Ultrasound Imaging and its modeling

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2002-01-01

    Modern medical ultrasound scanners are used for imaging nearly all soft tissue structures in the body. The anatomy can be studied from gray-scale B-mode images, where the reflectivity and scattering strength of the tissues are displayed. The imaging is performed in real time with 20 to 100 images...

  3. 3D Measurement Technology by Structured Light Using Stripe-Edge-Based Gray Code

    International Nuclear Information System (INIS)

    Wu, H B; Chen, Y; Wu, M Y; Guan, C R; Yu, X Y

    2006-01-01

    The key problem of 3D vision measurement using triangle method based on structured light is to acquiring projecting angle of projecting light accurately. In order to acquire projecting angle thereby determine the corresponding relationship between sampling point and image point, method for encoding and decoding structured light based on stripe edge of Gray code is presented. The method encoded with Gray code stripe and decoded with stripe edge acquired by sub-pixel technology instead of pixel centre, so latter one-bit decoding error was removed. Accuracy of image sampling point location and correspondence between image sampling point and object sampling point achieved sub-pixel degree. In addition, measurement error caused by dividing projecting angle irregularly by even-width encoding stripe was analysed and corrected. Encoding and decoding principle and decoding equations were described. Finally, 3dsmax and Matlab software were used to simulate measurement system and reconstruct measured surface. Indicated by experimental results, measurement error is about 0.05%

  4. Alexithymia is related to differences in gray matter volume: a voxel-based morphometry study.

    Science.gov (United States)

    Ihme, Klas; Dannlowski, Udo; Lichev, Vladimir; Stuhrmann, Anja; Grotegerd, Dominik; Rosenberg, Nicole; Kugel, Harald; Heindel, Walter; Arolt, Volker; Kersting, Anette; Suslow, Thomas

    2013-01-23

    Alexithymia has been characterized as the inability to identify and describe feelings. Functional imaging studies have revealed that alexithymia is linked to reactivity changes in emotion- and face-processing-relevant brain areas. In this respect, anterior cingulate cortex (ACC), amygdala, anterior insula and fusiform gyrus (FFG) have been consistently reported. However, it remains to be clarified whether alexithymia is also associated with structural differences. Voxel-based morphometry on T1-weighted magnetic resonance images was used to investigate gray matter volume in 17 high alexithymics (HA) and 17 gender-matched low alexithymics (LA), which were selected from a sample of 161 healthy volunteers on basis of the 20-item Toronto Alexithymia Scale. Data were analyzed as statistic parametric maps for the comparisons LA>HA and HA>LA in a priori determined regions of interests (ROIs), i.e., ACC, amygdala, anterior insula and FFG. Moreover, an exploratory whole brain analysis was accomplished. For the contrast LA>HA, significant clusters were detected in the ACC, left amygdala and left anterior insula. Additionally, the whole brain analysis revealed volume differences in the left middle temporal gyrus. No significant differences were found for the comparison HA>LA. Our findings suggest that high compared to low alexithymics show less gray matter volume in several emotion-relevant brain areas. These structural differences might contribute to the functional alterations found in previous imaging studies in alexithymia. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Differences in neurotransmitter systems of ventrolateral periaqueductal gray between the micturition reflex and nociceptive regulation: An in vivo microdialysis study.

    Science.gov (United States)

    Kitta, Takeya; Mitsui, Takahiko; Kanno, Yukiko; Chiba, Hiroki; Moriya, Kimihiko; Yoshioka, Mitsuhiro; Shinohara, Nobuo

    2016-07-01

    To elucidate the possible involvement of glutamate and serotonin (5-hydroxytryptamine) neurons in the ventrolateral midbrain periaqueductal gray during noxious stimulation. The study was carried out by evoking a noxious stimulation by acetic acid in an animal model of cystitis. Changes in glutamate and 5-hydroxytryptamine in the periaqueductal gray during the micturition reflex and acetic acid-induced cystitis were determined using in vivo microdialysis combined with cystometry in rats. Extracellular glutamate levels slightly, but significantly, increased during the micturition reflex induced by saline infusion into the bladder. Intravesical infusion of acetic acid facilitated the micturition reflex characterized by increases in voiding pressure and decreases in the intercontraction interval. Glutamate levels were markedly increased by acetic acid, and this enhancement was sustained for at least 3 h. 5-Hydroxytryptamine levels, which were not altered during the micturition reflex, were increased after intravesical infusion of acetic acid. The results suggest that periaqueductal gray glutamate and 5-hydroxytryptamine neurons differentially participate in the modulation of both nociception and the micturition reflex. Furthermore, periaqueductal gray 5-hydroxytryptamine levels appear to reflect the nociceptive stimuli. © 2016 The Japanese Urological Association.

  6. Utilization of a liquid crystal spatial light modulator in a gray scale detour phase method for Fourier holograms.

    Science.gov (United States)

    Makey, Ghaith; El-Daher, Moustafa Sayem; Al-Shufi, Kanj

    2012-11-10

    This paper introduces a new modification for the well-known binary detour phase method, which is largely used to represent Fourier holograms; the modification utilizes gray scale level control provided by a liquid crystal spatial light modulator to improve the traditional binary detour phase. Results are shown by both simulation and experiment.

  7. Gray matter anomalies in pedophiles with and without a history of child sexual offending.

    Science.gov (United States)

    Schiffer, B; Amelung, T; Pohl, A; Kaergel, C; Tenbergen, G; Gerwinn, H; Mohnke, S; Massau, C; Matthias, W; Weiß, S; Marr, V; Beier, K M; Walter, M; Ponseti, J; Krüger, T H C; Schiltz, K; Walter, H

    2017-05-16

    Pedophilia is a psychiatric disorder that is inter-related with but distinct from child sexual offending (CSO). Neural alterations reportedly contribute to both pedophilia and CSO, but until now, no study has distinguished the brain structural anomalies associated with pedophilia from those specifically associated with CSO in pedophilic men. Using high-resolution T1-weighted brain images and voxel-based morphometry, we analyzed the gray matter (GM) volume of the following 219 men recruited at four acquisition sites in Germany: 58 pedophiles with a history of CSO, 60 pedophiles without any history of CSO and 101 non-pedophilic, non-offending controls to control for the effects of age, education level, verbal IQ, sexual orientation and the acquisition site. Although there were no differences in the relative GM volume of the brain specifically associated with pedophilia, statistical parametric maps revealed a highly significant and CSO-related pattern of above vs below the 'normal' GM volume in the right temporal pole, with non-offending pedophiles exhibiting larger volumes than offending pedophiles. Moreover, regression analysis revealed that the lower GM volume of the dorsomedial prefrontal or anterior cingulate cortex was associated with a higher risk of re-offending in pedophilic child molesters. We believe our data provide the first evidence that CSO in pedophilia rather than pedophilia alone is associated with GM anomalies and thus shed new light on the results of previous studies on this topic. These results indicate the need for new neurobehavioral theories on pedophilia and CSO and may be potentially useful for treatment or prevention approaches that aim to reduce the risk of (re)offending in pedophilia.

  8. A study on cognitive impairment and gray matter volume abnormalities in silent cerebral infarction patients

    International Nuclear Information System (INIS)

    Luo, Wei; Wei, Xiaofeng; Li, Mengxiong; Jiang, Xun; Li, Shanshan

    2015-01-01

    The relationship between silent cerebral infarction (SCI) and the integrity of cognitive function is unknown. We intended to investigate whether cognitive impairment is associated with gray matter volume (GMV) in the SCI patients. Sixty-two patients with SCI and 62 age- and gender-matched healthy controls (HC) were evaluated with P300 test, Montreal Cognitive Assessment (MoCA) test, Hamilton Anxiety Scale (HAMA), and Hamilton Depression Scale (HDRS). Whole brain high-resolution T1-weighted images were processed with SPM12b software and analyzed by voxel-based morphometry (VBM). Correlation analysis was performed between the GMV and the scores of MoCA Scale, P300 latency, P300 amplitude, HAMA, HDRS, age, and educational level. The brains of the SCI patients have a significant reduction in GMV in the left superior and inferior frontal gyrus, left superior temporal gyrus, right middle temporal gyrus, and bilateral hippocampus gyrus (p < 0.01, FDR correction). No significant increase of GMV was detected. The GMV of their frontal and temporal lobes is positively correlated with the score of MoCA scale and P300 amplitude (r ≥ 0.62, p < 0.01). The GMV of frontal, temporal, and hippocampus is negatively correlated with P300 latency (r ≤ -0.71, p < 0.05). No significant correlation between the GMV of abnormal brain regions and another two clinical characteristics was found. SCI patients have impaired cognitive function and reduced GMV compared to the HC subjects. The neuropathological basis of such cognitive deficits in SCI patients might be a reduced GMV. (orig.)

  9. Adaptive modulation of adult brain gray and white matter to high altitude: structural MRI studies.

    Directory of Open Access Journals (Sweden)

    Jiaxing Zhang

    Full Text Available The aim of this study was to investigate brain structural alterations in adult immigrants who adapted to high altitude (HA. Voxel-based morphometry analysis of gray matter (GM volumes, surface-based analysis of cortical thickness, and Tract-Based Spatial Statistics analysis of white matter fractional anisotropy (FA based on MRI images were conducted on 16 adults (20-22 years who immigrated to the Qinghai-Tibet Plateau (2300-4400 m for 2 years. They had no chronic mountain sickness. Control group consisted of 16 matched sea level subjects. A battery of neuropsychological tests was also conducted. HA immigrants showed significantly decreased GM volumes in the right postcentral gyrus and right superior frontal gyrus, and increased GM volumes in the right middle frontal gyrus, right parahippocampal gyrus, right inferior and middle temporal gyri, bilateral inferior ventral pons, and right cerebellum crus1. While there was some divergence in the left hemisphere, surface-based patterns of GM changes in the right hemisphere resembled those seen for VBM analysis. FA changes were observed in multiple WM tracts. HA immigrants showed significant impairment in pulmonary function, increase in reaction time, and deficit in mental rotation. Parahippocampal and middle frontal GM volumes correlated with vital capacity. Superior frontal GM volume correlated with mental rotation and postcentral GM correlated with reaction time. Paracentral lobule and frontal FA correlated with mental rotation reaction time. There might be structural modifications occurred in the adult immigrants during adaptation to HA. The changes in GM may be related to impaired respiratory function and psychological deficits.

  10. A study on cognitive impairment and gray matter volume abnormalities in silent cerebral infarction patients

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Wei; Wei, Xiaofeng; Li, Mengxiong [The First Affiliated Hospital of Yangtze University, Biomedical Engineering Laboratory, Jingzhou, Hubei (China); Jiang, Xun [Renmin Hospital of Wuhan University, Biomedical Engineering Laboratory, Wuhan, Hubei (China); Li, Shanshan [JingZhou City Central Blood Bank, Jingzhou, Hubei (China)

    2015-08-15

    The relationship between silent cerebral infarction (SCI) and the integrity of cognitive function is unknown. We intended to investigate whether cognitive impairment is associated with gray matter volume (GMV) in the SCI patients. Sixty-two patients with SCI and 62 age- and gender-matched healthy controls (HC) were evaluated with P300 test, Montreal Cognitive Assessment (MoCA) test, Hamilton Anxiety Scale (HAMA), and Hamilton Depression Scale (HDRS). Whole brain high-resolution T1-weighted images were processed with SPM12b software and analyzed by voxel-based morphometry (VBM). Correlation analysis was performed between the GMV and the scores of MoCA Scale, P300 latency, P300 amplitude, HAMA, HDRS, age, and educational level. The brains of the SCI patients have a significant reduction in GMV in the left superior and inferior frontal gyrus, left superior temporal gyrus, right middle temporal gyrus, and bilateral hippocampus gyrus (p < 0.01, FDR correction). No significant increase of GMV was detected. The GMV of their frontal and temporal lobes is positively correlated with the score of MoCA scale and P300 amplitude (r ≥ 0.62, p < 0.01). The GMV of frontal, temporal, and hippocampus is negatively correlated with P300 latency (r ≤ -0.71, p < 0.05). No significant correlation between the GMV of abnormal brain regions and another two clinical characteristics was found. SCI patients have impaired cognitive function and reduced GMV compared to the HC subjects. The neuropathological basis of such cognitive deficits in SCI patients might be a reduced GMV. (orig.)

  11. Cost-Efficient Wafer-Level Capping for MEMS and Imaging Sensors by Adhesive Wafer Bonding

    Directory of Open Access Journals (Sweden)

    Simon J. Bleiker

    2016-10-01

    Full Text Available Device encapsulation and packaging often constitutes a substantial part of the fabrication cost of micro electro-mechanical systems (MEMS transducers and imaging sensor devices. In this paper, we propose a simple and cost-effective wafer-level capping method that utilizes a limited number of highly standardized process steps as well as low-cost materials. The proposed capping process is based on low-temperature adhesive wafer bonding, which ensures full complementary metal-oxide-semiconductor (CMOS compatibility. All necessary fabrication steps for the wafer bonding, such as cavity formation and deposition of the adhesive, are performed on the capping substrate. The polymer adhesive is deposited by spray-coating on the capping wafer containing the cavities. Thus, no lithographic patterning of the polymer adhesive is needed, and material waste is minimized. Furthermore, this process does not require any additional fabrication steps on the device wafer, which lowers the process complexity and fabrication costs. We demonstrate the proposed capping method by packaging two different MEMS devices. The two MEMS devices include a vibration sensor and an acceleration switch, which employ two different electrical interconnection schemes. The experimental results show wafer-level capping with excellent bond quality due to the re-flow behavior of the polymer adhesive. No impediment to the functionality of the MEMS devices was observed, which indicates that the encapsulation does not introduce significant tensile nor compressive stresses. Thus, we present a highly versatile, robust, and cost-efficient capping method for components such as MEMS and imaging sensors.

  12. Digital image analyser for autoradiography

    International Nuclear Information System (INIS)

    Muth, R.A.; Plotnick, J.

    1985-01-01

    The most critical parameter in quantitative autoradiography for assay of tissue concentrations of tracers is the ability to obtain precise and accurate measurements of optical density of the images. Existing high precision systems for image analysis, rotating drum densitometers, are expensive, suffer from mechanical problems and are slow. More moderately priced and reliable video camera based systems are available, but their outputs generally do not have the uniformity and stability necessary for high resolution quantitative autoradiography. The authors have designed and constructed an image analyser optimized for quantitative single and multiple tracer autoradiography which the authors refer to as a memory-mapped charged-coupled device scanner (MM-CCD). The input is from a linear array of CCD's which is used to optically scan the autoradiograph. Images are digitized into 512 x 512 picture elements with 256 gray levels and the data is stored in buffer video memory in less than two seconds. Images can then be transferred to RAM memory by direct memory-mapping for further processing. Arterial blood curve data and optical density-calibrated standards data can be entered and the optical density images can be converted automatically to tracer concentration or functional images. In double tracer studies, images produced from both exposures can be stored and processed in RAM to yield ''pure'' individual tracer concentration or functional images. Any processed image can be transmitted back to the buffer memory to be viewed on a monitor and processed for region of interest analysis

  13. On the detection of pornographic digital images

    Science.gov (United States)

    Schettini, Raimondo; Brambilla, Carla; Cusano, Claudio; Ciocca, Gianluigi

    2003-06-01

    The paper addresses the problem of distinguishing between pornographic and non-pornographic photographs, for the design of semantic filters for the web. Both, decision forests of trees built according to CART (Classification And Regression Trees) methodology and Support Vectors Machines (SVM), have been used to perform the classification. The photographs are described by a set of low-level features, features that can be automatically computed simply on gray-level and color representation of the image. The database used in our experiments contained 1500 photographs, 750 of which labeled as pornographic on the basis of the independent judgement of several viewers.

  14. Correlation between imaging findings and autoantibody levels and prognosis in patients with neuropsychiatric systemic lupus erythematosus

    International Nuclear Information System (INIS)

    Zhou Guangyu; Han Xuemei; Jin Ling

    2013-01-01

    Objective: To investigate the correlation between cranial magnetic resonance imaging (MRI) findings and autoantibody levels in patients with neuropsychiatric systemic lupus erythematosus (NPSLE), and to elucidate the role of MRI findings in predicting the prognosis of NPSLE. Methods: In total, 36 well-documented cases of NPSLE diagnosed definitely were selected. All the patients were divided into survival group (n=27) and dead group (n=9). Anti-nuclear antibodies and anti-dsDNA antibodies in serum were detected by indirect immunofluorescence and colloidal gold spot penetration method, respectively. Immunoblotting method was used to detect anti-Sm, anti-SSA, anti-SSB, anti U1-RNP, and anti-ribosomal P protein antibodies. Anti-cardiolipin antibody (ACL) was detected byELISA method. The correlation between MRI findings of cerebral lesions and autoantibodies, and prognosis was analyzed. Results: Cranial MRI scans on admission were abnormal in 32 patients (88.9% ), among which 21 cases showed diffuse manifestations, 10 cases showed focal lesion in brain and 1 case showed brain atrophy. The diffuse lesion on MRI showed multiple spotty or patchy normal intensity signal on T 1 -weighted image (T 1 WI) and high-intensity signal changes on T 2 -weighted image (T 2 WI). The focal lesion showed single spotty or patchy normal intensity signal on T 1 WI and high-intensity signal changes on T 2 WI. The lesion sites included basal ganglia, subcortical white matter, anterior and posterior horn of lateral ventricle, semiovale center, cerebral cortex, brainstem and cerebellum. Of 9 patients in dead group, 6 cases presented with focal lesion and the percentage of focal lesion cases in dead group was significantly higher than that in survival group (P<0.01). The percentages of lesion number in brainstem and basal ganglia in dead group were 11.5% and 26.9% , respectively, which were significantly higher than those in survival group (P<0.05 or P<0.01). The positive rate of ACL in cases

  15. Natural color image segmentation using integrated mechanism

    Institute of Scientific and Technical Information of China (English)

    Jie Xu (徐杰); Pengfei Shi (施鹏飞)

    2003-01-01

    A new method for natural color image segmentation using integrated mechanism is proposed in this paper.Edges are first detected in term of the high phase congruency in the gray-level image. K-mean cluster is used to label long edge lines based on the global color information to estimate roughly the distribution of objects in the image, while short ones are merged based on their positions and local color differences to eliminate the negative affection caused by texture or other trivial features in image. Region growing technique is employed to achieve final segmentation results. The proposed method unifies edges, whole and local color distributions, as well as spatial information to solve the natural image segmentation problem.The feasibility and effectiveness of this method have been demonstrated by various experiments.

  16. Correspondence Between Aberrant Intrinsic Network Connectivity and Gray-Matter Volume in the Ventral Brain of Preterm Born Adults.

    Science.gov (United States)

    Bäuml, Josef G; Daamen, Marcel; Meng, Chun; Neitzel, Julia; Scheef, Lukas; Jaekel, Julia; Busch, Barbara; Baumann, Nicole; Bartmann, Peter; Wolke, Dieter; Boecker, Henning; Wohlschläger, Afra M; Sorg, Christian

    2015-11-01

    Widespread brain changes are present in preterm born infants, adolescents, and even adults. While neurobiological models of prematurity facilitate powerful explanations for the adverse effects of preterm birth on the developing brain at microscale, convincing linking principles at large-scale level to explain the widespread nature of brain changes are still missing. We investigated effects of preterm birth on the brain's large-scale intrinsic networks and their relation to brain structure in preterm born adults. In 95 preterm and 83 full-term born adults, structural and functional magnetic resonance imaging at-rest was used to analyze both voxel-based morphometry and spatial patterns of functional connectivity in ongoing blood oxygenation level-dependent activity. Differences in intrinsic functional connectivity (iFC) were found in cortical and subcortical networks. Structural differences were located in subcortical, temporal, and cingulate areas. Critically, for preterm born adults, iFC-network differences were overlapping and correlating with aberrant regional gray-matter (GM) volume specifically in subcortical and temporal areas. Overlapping changes were predicted by prematurity and in particular by neonatal medical complications. These results provide evidence that preterm birth has long-lasting effects on functional connectivity of intrinsic networks, and these changes are specifically related to structural alterations in ventral brain GM. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Análise por imagem digital dos níveis de cinza de fibras de reforço associadas a uma resina composta = Digital image analysis of the gray levels of reinforcement fibers associated with composite resin

    Directory of Open Access Journals (Sweden)

    Mussatto, Cristiane Maria Boniatti

    2005-01-01

    Full Text Available Mensurar a densidade óptica das fibras de reforço Connect, Ribbond e Interlig incluídas em resina composta Filtek Z250, no sistema DenOptix. Materiais e método: Foram confeccionados 10 blocos de resina composta associadas a cada tipo de fibra e dois blocos de resina Z250 pura (controle não-reforçado, totalizando 32 corpos-de-prova. Foram obtidas 3 radiografias digitais de cada corpo-de-prova, sobre uma placa óptica do sistema DenOptix, para cada posição: (A face lateral da fibra exposta aos raios -X; (B face tramada da fibra exposta aos raios-X. Em cada uma foram realizadas 3 leituras ópticas dos níveis de cinza em cada corpo-de-prova, em pontos aleatórios, sendo obtida uma média. Os valores médios dos níveis de cinza foram analisados pelo teste t de Student, ANOVA e teste de Tukey, ao nível de significância de 1%. Resultados e conclusões: Com relação à associação da resina + fibra na posição (A, observou-se a maior média de níveis de cinza para a resina pura, seguido por resina + Connect, resina + Interlig (que não diferiram entre si, e resina + Ribbond. Com relação à associação da resina + fibra na posição (B, observou-se que a resina pura apresentou maior média, seguida por resina + Connect, resina + Interlig e resina + Ribbond, sendo que as duas últimas não foram diferentes entre si. Os resultados sugerem que os níveis de cinza variaram em função do tipo de fibra de reforço e da posição na radiografia

  18. Spoofing detection on facial images recognition using LBP and GLCM combination

    Science.gov (United States)

    Sthevanie, F.; Ramadhani, K. N.

    2018-03-01

    The challenge for the facial based security system is how to detect facial image falsification such as facial image spoofing. Spoofing occurs when someone try to pretend as a registered user to obtain illegal access and gain advantage from the protected system. This research implements facial image spoofing detection method by analyzing image texture. The proposed method for texture analysis combines the Local Binary Pattern (LBP) and Gray Level Co-occurrence Matrix (GLCM) method. The experimental results show that spoofing detection using LBP and GLCM combination achieves high detection rate compared to that of using only LBP feature or GLCM feature.

  19. Median Filter Noise Reduction of Image and Backpropagation Neural Network Model for Cervical Cancer Classification

    Science.gov (United States)

    Wutsqa, D. U.; Marwah, M.

    2017-06-01

    In this paper, we consider spatial operation median filter to reduce the noise in the cervical images yielded by colposcopy tool. The backpropagation neural network (BPNN) model is applied to the colposcopy images to classify cervical cancer. The classification process requires an image extraction by using a gray level co-occurrence matrix (GLCM) method to obtain image features that are used as inputs of BPNN model. The advantage of noise reduction is evaluated by comparing the performances of BPNN models with and without spatial operation median filter. The experimental result shows that the spatial operation median filter can improve the accuracy of the BPNN model for cervical cancer classification.

  20. Evaluation of Yogurt Microstructure Using Confocal Laser Scanning Microscopy and Image Analysis.

    Science.gov (United States)

    Skytte, Jacob L; Ghita, Ovidiu; Whelan, Paul F; Andersen, Ulf; Møller, Flemming; Dahl, Anders B; Larsen, Rasmus

    2015-06-01

    The microstructure of protein networks in yogurts defines important physical properties of the yogurt and hereby partly its quality. Imaging this protein network using confocal scanning laser microscopy (CSLM) has shown good results, and CSLM has become a standard measuring technique for fermented dairy products. When studying such networks, hundreds of images can be obtained, and here image analysis methods are essential for using the images in statistical analysis. Previously, methods including gray level co-occurrence matrix analysis and fractal analysis have been used with success. However, a range of other image texture characterization methods exists. These methods describe an image by a frequency distribution of predefined image features (denoted textons). Our contribution is an investigation of the choice of image analysis methods by performing a comparative study of 7 major approaches to image texture description. Here, CSLM images from a yogurt fermentation study are investigated, where production factors including fat content, protein content, heat treatment, and incubation temperature are varied. The descriptors are evaluated through nearest neighbor classification, variance analysis, and cluster analysis. Our investigation suggests that the texton-based descriptors provide a fuller description of the images compared to gray-level co-occurrence matrix descriptors and fractal analysis, while still being as applicable and in some cases as easy to tune. © 2015 Institute of Food Technologists®

  1. QCA Gray Code Converter Circuits Using LTEx Methodology

    Science.gov (United States)

    Mukherjee, Chiradeep; Panda, Saradindu; Mukhopadhyay, Asish Kumar; Maji, Bansibadan

    2018-04-01

    The Quantum-dot Cellular Automata (QCA) is the prominent paradigm of nanotechnology considered to continue the computation at deep sub-micron regime. The QCA realizations of several multilevel circuit of arithmetic logic unit have been introduced in the recent years. However, as high fan-in Binary to Gray (B2G) and Gray to Binary (G2B) Converters exist in the processor based architecture, no attention has been paid towards the QCA instantiation of the Gray Code Converters which are anticipated to be used in 8-bit, 16-bit, 32-bit or even more bit addressable machines of Gray Code Addressing schemes. In this work the two-input Layered T module is presented to exploit the operation of an Exclusive-OR Gate (namely LTEx module) as an elemental block. The "defect-tolerant analysis" of the two-input LTEx module has been analyzed to establish the scalability and reproducibility of the LTEx module in the complex circuits. The novel formulations exploiting the operability of the LTEx module have been proposed to instantiate area-delay efficient B2G and G2B Converters which can be exclusively used in Gray Code Addressing schemes. Moreover this work formulates the QCA design metrics such as O-Cost, Effective area, Delay and Cost α for the n-bit converter layouts.

  2. Evaluation of Accelerated Graphitic Corrosion Test of Gray Cast Iron

    International Nuclear Information System (INIS)

    Kim, Jeong Hyeon; Hong, Jong Dae; Chang Heui; Na, Kyung Hwan; Lee, Jae Gon

    2011-01-01

    In operating nuclear power plants, gray cast iron is commonly used as materials for various non-safety system components including pipes in fire water system, valve bodies, bonnets, and pump castings. In such locations, operating condition does not require alloy steels with excellent mechanical properties. But, a few corrosion related degradation, or graphitic corrosion is frequently occurred to gray cast iron during the long-term operation in nuclear power plant. Graphitic corrosion is selective leaching of iron from gray cast iron, where iron gets removed and graphite grains remain intact. In U.S.A., one-time visual inspection and hardness measurement are required from regulatory body to detect the graphitic corrosion for the life extension evaluation of the operating nuclear power plant. In this study, experiments were conducted to make accelerated graphitic corrosion of gray cast iron using electrochemical method, and hardness was measured for the specimens to establish the correlation between degree of graphitic corrosion and surface hardness of gray cast iron

  3. Early Childhood Depression and Alterations in the Trajectory of Gray Matter Maturation in Middle Childhood and Early Adolescence.

    Science.gov (United States)

    Luby, Joan L; Belden, Andy C; Jackson, Joshua J; Lessov-Schlaggar, Christina N; Harms, Michael P; Tillman, Rebecca; Botteron, Kelly; Whalen, Diana; Barch, Deanna M

    2016-01-01

    The trajectory of cortical gray matter development in childhood has been characterized by early neurogenesis and volume increase, peaking at puberty followed by selective elimination and myelination, resulting in volume loss and thinning. This inverted U-shaped trajectory, as well as cortical thickness, has been associated with cognitive and emotional function. Synaptic pruning-based volume decline has been related to experience-dependent plasticity in animals. To date, there have been no data to inform whether and how childhood depression might be associated with this trajectory. To examine the effects of early childhood depression, from the preschool age to the school age period, on cortical gray matter development measured across 3 waves of neuroimaging from late school age to early adolescence. Data were collected in an academic research setting from September 22, 2003, to December 13, 2014, on 193 children aged 3 to 6 years from the St Louis, Missouri, metropolitan area who were observed for up to 11 years in a longitudinal behavioral and neuroimaging study of childhood depression. Multilevel modeling was applied to explore the association between the number of childhood depression symptoms and prior diagnosis of major depressive disorder and the trajectory of gray matter change across 3 scan waves. Data analysis was conducted from October 29, 2014, to September 28, 2015. Volume, thickness, and surface area of cortical gray matter measured using structural magnetic resonance imaging at 3 scan waves. Of the 193 children, 90 had a diagnosis of major depressive disorder; 116 children had 3 full waves of neuroimaging scans. Findings demonstrated marked alterations in cortical gray matter volume loss (slope estimate, -0.93 cm³; 95% CI, -1.75 to -0.10 cm³ per scan wave) and thinning (slope estimate, -0.0044 mm; 95% CI, -0.0077 to -0.0012 mm per scan wave) associated with experiencing an episode of major depressive disorder before the first magnetic resonance

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

    International Nuclear Information System (INIS)

    Liu Yue; Peng Yun; Gao Peiyi; Nie Binbin; Lu Chuankai; Zhang Liping; Ji Zhiying; Yin Guangheng; Yu Tong; Shan Baoci

    2012-01-01

    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 T 1 WI 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 (mm 3 ) 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 mm 3 (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 mm 3 (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)

  5. Changes in the white-gray matter density difference in computed tomography associated with maturation

    International Nuclear Information System (INIS)

    Tsuchiya, Setsuko; Maruyama, Hiroshi; Maruyama, Kazuko

    1980-01-01

    The attenuation of the x-ray beam in infantile brain tissue is markedly lower than in adults, so the CT image in infants, particularly in the newborn, seems to indicate demyelinating diseases. Therefore, the evaluation of nonpathological scans of infants and adults was performed in order to establish baseline numerical data on white and gray matter differentiation associated with maturation. One hundred and nine normal cases with no motion artifacts were selected. The age distribution was from 39 weeks to 40 years, as shown in Fig. 1. The Hitachi CT-H 250 tomograph was used for all the patient scans. The x-ray tube was operated at 120 kV and 30 mA. The thickness of each slice was 10 mm. The patients were scanned parallel with the canthomeatal line. The CT numbers are displayed on the EMI scale, in which water is zero and bone is +500. The mean CT numbers and the standard deviation were calculated by means of a computer on a horizontal plane through the pineal body; the following regions were selected for computation: White matter: preventricular frontal area. 44 mm 2 (36 pixels). Gray matter: head of the caudate nucleus and the thalamus. 24 mm 2 (20 pixels). The mean CT number for white matter was 13.5 +- 0.5 in the newborn and 16.8 +- 0.4 in adults. These numbers increased very rapidly during the 2nd month after birth and reached the adult value by 13 years. On the other hand, the mean CT number for gray matter was 15.6 +- 0.6 in the newborn and 19.7 +- 0.4 in adults. These numbers increased only gradually after birth and reached maximum value at 20 years, These results are probably due to a decrease in the water content per unit of volume and an increase in brain solids (protein, RNA and myelin) rather than to a decrease in the extracellular space associated with maturation. The difference between the average white and gray value was also studied. The white-gray difference was lowest (1.6 units) at 2 months and highest (2.9 units) in adults. (author)

  6. Lower gray matter density and functional connectivity in the anterior insula in smokers compared with never smokers.

    Science.gov (United States)

    Stoeckel, Luke E; Chai, Xiaoqian J; Zhang, Jiahe; Whitfield-Gabrieli, Susan; Evins, A Eden

    2016-07-01

    Although nicotine addiction is characterized by both structural and functional abnormalities in brain networks involved in salience and cognitive control, few studies have integrated these data to understand how these abnormalities may support addiction. This study aimed to (1) evaluate gray matter density and functional connectivity of the anterior insula in cigarette smokers and never smokers and (2) characterize how differences in these measures were related to smoking behavior. We compared structural magnetic resonance imaging (MRI) (gray matter density via voxel-based morphometry) and seed-based functional connectivity MRI data in 16 minimally deprived smokers and 16 matched never smokers. Compared with controls, smokers had lower gray matter density in left anterior insula extending into inferior frontal and temporal cortex. Gray matter density in this region was inversely correlated with cigarettes smoked per day. Smokers exhibited negative functional connectivity (anti-correlation) between the anterior insula and regions involved in cognitive control (left lPFC) and semantic processing/emotion regulation (lateral temporal cortex), whereas controls exhibited positive connectivity between these regions. There were differences in the anterior insula, a central region in the brain's salience network, when comparing both volumetric and functional connectivity data between cigarette smokers and never smokers. Volumetric data, but not the functional connectivity data, were also associated with an aspect of smoking behavior (daily cigarettes smoked). © 2015 Society for the Study of Addiction.

  7. Uniformity and Deviation of Intra-axonal Cross-sectional Area Coverage of the Gray-to-White Matter Interface

    Directory of Open Access Journals (Sweden)

    Stefan Sommer

    2017-12-01

    Full Text Available Diffusion magnetic resonance imaging (dMRI is a compelling tool for investigating the structure and geometry of brain tissue based on indirect measurement of the diffusion anisotropy of water. Recent developments in global top-down tractogram optimizations enable the estimation of streamline weights, which characterize the connection between gray matter areas. In this work, the intra-axonal cross-sectional area coverage of the gray-to-white matter interface was examined by intersecting tractography streamlines with cortical regions of interest. The area coverage is the ratio of streamline weights divided by the surface area at the gray-to-white matter interface and assesses the estimated percentage which is covered by intra-axonal space. A high correlation (r = 0.935 between streamline weights and the cortical surface area was found across all regions of interest in all subjects. The variance across different cortical regions exhibits similarities to myelin maps. Additionally, we examined the effect of different diffusion gradient subsets at a lower, clinically feasible spatial resolution. Subsampling of the initial high-resolution diffusion dataset did not alter the tendency of the area coverage at the gray-to-white matter interface across cortical areas and subjects. However, single-shell acquisition schemes with lower b-values lead to a steady increase in area coverage in comparison to the full acquisition scheme at high resolution.

  8. Gray matter deficits and altered resting-state connectivity in the superior temporal gyrus among individuals with problematic hypersexual behavior.

    Science.gov (United States)

    Seok, Ji-Woo; Sohn, Jin-Hun

    2018-04-01

    Neuroimaging studies on the characteristics of hypersexual disorder have been accumulating, yet alternations in brain structures and functional connectivity in individuals with problematic hypersexual behavior (PHB) has only recently been studied. This study aimed to investigate gray matter deficits and resting-state abnormalities in individuals with PHB using voxel-based morphometry and resting-state connectivity analysis. Seventeen individuals with PHB and 19 age-matched healthy controls participated in this study. Gray matter volume of the brain and resting-state connectivity were measured using 3T magnetic resonance imaging. Compared to healthy subjects, individuals with PHB had significant reductions in gray matter volume in the left superior temporal gyrus (STG) and right middle temporal gyrus. Individuals with PHB also exhibited a decrease in resting-state functional connectivity between the left STG and left precuneus and between the left STG and right caudate. The gray matter volume of the left STG and its resting-state functional connectivity with the right caudate both showed significant negative correlations with the severity of PHB. The findings suggest that structural deficits and resting-state functional impairments in the left STG might be linked to PHB and provide new insights into the underlying neural mechanisms of PHB. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Gray and white matter correlates of the Big Five personality traits.

    Science.gov (United States)

    Privado, Jesús; Román, Francisco J; Saénz-Urturi, Carlota; Burgaleta, Miguel; Colom, Roberto

    2017-05-04

    Personality neuroscience defines the scientific study of the neurobiological basis of personality. This field assumes that individual differences in personality traits are related with structural and functional variations of the human brain. Gray and white matters are structural properties considered separately in previous research. Available findings in this regard are largely disparate. Here we analyze the relationships between gray matter (cortical thickness (CT), cortical surface area (CSA), and cortical volume) and integrity scores obtained after several white matter tracts connecting different brain regions, with individual differences in the personality traits comprised by the Five-Factor Model (extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience). These psychological and biological data were obtained from young healthy women. The main findings showed statistically significant associations between occipital CSA variations and extraversion, as well as between parietal CT variations and neuroticism. Regarding white matter integrity, openness showed positive correlations with tracts connecting posterior and anterior brain regions. Therefore, variations in discrete gray matter clusters were associated with temperamental traits (extraversion and neuroticism), whereas long-distance structural connections were related with the dimension of personality that has been associated with high-level cognitive processes (openness). Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. An FPGA-based heterogeneous image fusion system design method

    Science.gov (United States)

    Song, Le; Lin, Yu-chi; Chen, Yan-hua; Zhao, Mei-rong

    2011-08-01

    Taking the advantages of FPGA's low cost and compact structure, an FPGA-based heterogeneous image fusion platform is established in this study. Altera's Cyclone IV series FPGA is adopted as the core processor of the platform, and the visible light CCD camera and infrared thermal imager are used as the image-capturing device in order to obtain dualchannel heterogeneous video images. Tailor-made image fusion algorithms such as gray-scale weighted averaging, maximum selection and minimum selection methods are analyzed and compared. VHDL language and the synchronous design method are utilized to perform a reliable RTL-level description. Altera's Quartus II 9.0 software is applied to simulate and implement the algorithm modules. The contrast experiments of various fusion algorithms show that, preferably image quality of the heterogeneous image fusion can be obtained on top of the proposed system. The applied range of the different fusion algorithms is also discussed.

  11. Homocysteine plasma levels in patients suspected coronary artery disease: Relation to myocardial perfusion image

    International Nuclear Information System (INIS)

    Yao, Z.Y.; He, Q.; Qu, W.

    2002-01-01

    Purpose: Although there is considerable epidemiologic evidence for a relationship between plasma homocysteine (Hcy) levels and coronary artery disease (CAD), not all studies, especially prospective ones have shown such a relationship. The purpose of this study was to investigate a possible association between Hcy plasma levels and myocardial perfusion defect by SPECT in patients suspected CAD. Methods and Materials: A cohort of 238 patients suspected CAD (age: 60.65±10.43, male to female: 172: 66) was examined for Hcy, tetrahydrofolic acid (FH4), vitamine B12 and coronary angiography (CAG). Furthermore, 42 patients also underwent 99m Tc-MIBI myocardial perfusion images (MPI) to assess the myocardial perfusion. Results: There were 69 patients with normal CAG and 63, 60, 42 and 4 patients with 1 vessel, two vessel, 3 vessel and left main coronary stenosis. The plasma Hcy of this group was significantly increased, p 0.05. In patients with >=3 segments myocardial perfusion defect, 10 of them had normal Hcy, and 7 with hyperhomocysteinemia, in patients with 0.05). Conclusion: Our data may indicate that hyperhomocysteinemia represents an independent risk factor in patients with high possibility of CAD rather than a mark of myocardial ischemia or coronary stenosis

  12. Sexually dimorphic aggression indicates male gray wolves specialize in pack defense against conspecific groups.

    Science.gov (United States)

    Cassidy, Kira A; Mech, L David; MacNulty, Daniel R; Stahler, Daniel R; Smith, Douglas W

    2017-03-01

    Aggression directed at conspecific groups is common among gregarious, territorial species, and for some species such as gray wolves (Canis lupus) intraspecific strife is the leading cause of natural mortality. Each individual in a group likely has different measures of the costs and benefits associated with a group task, such as an aggressive attack on another group, which can alter motivation and behavior. We observed 292 inter-pack aggressive interactions in Yellowstone National Park between 1 April 1995 and 1 April 2011 (>5300days of observation) in order to determine the role of both sexes, and the influence of pack, age, and other traits on aggression. We recorded the behaviors and characteristics of all individuals present during the interactions (n=534 individuals) and which individuals participated in each step (i.e. chase, attack, kill, flight) of the interaction. Overall, all wolves were more likely to chase rivals if they outnumbered their opponent, suggesting packs accurately assess their opponent's size during encounters and individuals adjust their behavior based on relative pack size. Males were more likely than females to chase rival packs and gray-colored wolves were more aggressive than black-colored wolves. Male wolves and gray-colored wolves also recorded higher cortisol levels than females and black-colored wolves, indicating hormonal support for more intense aggressive behavior. Further, we found a positive correlation between male age and probability of chasing, while age-specific participation for females remained constant. Chasing behavior was influenced by the sex of lone intruders, with males more likely to chase male intruders. This difference in behavior suggests male and female wolves may have different strategies and motivations during inter-pack aggressive interactions related to gray wolf mating systems. A division of labor between pack members concerning resource and territory defense suggests selection for specific traits related

  13. Sexually dimorphic aggression indicates male gray wolves specialize in pack defense against conspecific groups

    Science.gov (United States)

    Cassidy, Kira A.; Mech, L. David; MacNulty, Daniel R; Stahler, Daniel R.; Smith, Douglas W.

    2017-01-01

    Aggression directed at conspecific groups is common among gregarious, territorial species, and for some species such as gray wolves (Canis lupus) intraspecific strife is the leading cause of natural mortality. Each individual in a group likely has different measures of the costs and benefits associated with a group task, such as an aggressive attack on another group, which can alter motivation and behavior. We observed 292 inter-pack aggressive interactions in Yellowstone National Park between 1 April 1995 and 1 April 2011 (>5300 days of observation) in order to determine the role of both sexes, and the influence of pack, age, and other traits on aggression. We recorded the behaviors and characteristics of all individuals present during the interactions (n = 534 individuals) and which individuals participated in each step (i.e. chase, attack, kill, flight) of the interaction. Overall, all wolves were more likely to chase rivals if they outnumbered their opponent, suggesting packs accurately assess their opponent’s size during encounters and individuals adjust their behavior based on relative pack size. Males were more likely than females to chase rival packs and gray-colored wolves were more aggressive than black-colored wolves. Male wolves and gray-colored wolves also recorded higher cortisol levels than females and black-colored wolves, indicating hormonal support for more intense aggressive behavior. Further, we found a positive correlation between male age and probability of chasing, while age-specific participation for females remained constant. Chasing behavior was influenced by the sex of lone intruders, with males more likely to chase male intruders. This difference in behavior suggests male and female wolves may have different strategies and motivations during inter-pack aggressive interactions related to gray wolf mating systems. A division of labor between pack members concerning resource and territory defense suggests selection for specific traits

  14. Computer-aided mass detection in mammography: False positive reduction via gray-scale invariant ranklet texture features

    International Nuclear Information System (INIS)

    Masotti, Matteo; Lanconelli, Nico; Campanini, Renato

    2009-01-01

    In this work, gray-scale invariant ranklet texture features are proposed for false positive reduction (FPR) in computer-aided detection (CAD) of breast masses. Two main considerations are at the basis of this proposal. First, false positive (FP) marks surviving our previous CAD system seem to be characterized by specific texture properties that can be used to discriminate them from masses. Second, our previous CAD system achieves invariance to linear/nonlinear monotonic gray-scale transformations by encoding regions of interest into ranklet images through the ranklet transform, an image transformation similar to the wavelet transform, yet dealing with pixels' ranks rather than with their gray-scale values. Therefore, the new FPR approach proposed herein defines a set of texture features which are calculated directly from the ranklet images corresponding to the regions of interest surviving our previous CAD system, hence, ranklet texture features; then, a support vector machine (SVM) classifier is used for discrimination. As a result of this approach, texture-based information is used to discriminate FP marks surviving our previous CAD system; at the same time, invariance to linear/nonlinear monotonic gray-scale transformations of the new CAD system is guaranteed, as ranklet texture features are calculated from ranklet images that have this property themselves by construction. To emphasize the gray-scale invariance of both the previous and new CAD systems, training and testing are carried out without any in-between parameters' adjustment on mammograms having different gray-scale dynamics; in particular, training is carried out on analog digitized mammograms taken from a publicly available digital database, whereas testing is performed on full-field digital mammograms taken from an in-house database. Free-response receiver operating characteristic (FROC) curve analysis of the two CAD systems demonstrates that the new approach achieves a higher reduction of FP marks

  15. Evaluation of computer imaging technique for predicting the SPAD readings in potato leaves

    Directory of Open Access Journals (Sweden)

    M.S. Borhan

    2017-12-01

    Full Text Available Facilitating non-contact measurement, a computer-imaging system was devised and evaluated to predict the chlorophyll content in po