WorldWideScience

Sample records for psf-matched difference imaging

  1. Image PSF-matching and subtraction: a powerful astronomical technique and its application to industrial imaging

    Science.gov (United States)

    Butler, Raymond F.; O'Tuairisg, Seathrun; Shearer, Andrew; Golden, Aaron

    2003-03-01

    There is a family of difficult image-processing scenarios which involve seeking out and quantifying minute changes within a sequence of near-identical images. Traditionally these have been dealt with by carefully registering the images in terms of position, orientiation and intensity, and subtracting them from some template image. However, for critical measurements, this approach breaks down if the point-spread-functions (PSFs) vary even slightly from image to image. Subtraction of registered images whose PSFs are not matched leads to considerable residual structure, which may be mistakenly interpreted as real features rather than processing artefacts. In astronomy, software known as ISIS has been developed to fully PSF-match image sequences and to facilitate their analysis. We show here the tremendous improvement in detection rates and measurement accuracy which ISIS has afforded in our program for the study of rare variable stars in dense, globular star clusters. We discuss the genesis from this work of our new program to use ISIS to search for extra-solar planets in transit across the face of stars in such clusters. Finally we illustrate an application of ISIS in the industrial imaging sector, showing how it can be used to detect minute faults in images of products.

  2. T-PHOT: A new code for PSF-matched, prior-based, multiwavelength extragalactic deconfusion photometry

    Science.gov (United States)

    Merlin, E.; Fontana, A.; Ferguson, H. C.; Dunlop, J. S.; Elbaz, D.; Bourne, N.; Bruce, V. A.; Buitrago, F.; Castellano, M.; Schreiber, C.; Grazian, A.; McLure, R. J.; Okumura, K.; Shu, X.; Wang, T.; Amorín, R.; Boutsia, K.; Cappelluti, N.; Comastri, A.; Derriere, S.; Faber, S. M.; Santini, P.

    2015-10-01

    Context. The advent of deep multiwavelength extragalactic surveys has led to the necessity for advanced and fast methods for photometric analysis. In fact, codes which allow analyses of the same regions of the sky observed at different wavelengths and resolutions are becoming essential to thoroughly exploit current and future data. In this context, a key issue is the confusion (i.e. blending) of sources in low-resolution images. Aims: We present t-phot, a publicly available software package developed within the astrodeep project. t-phot is aimed at extracting accurate photometry from low-resolution images, where the blending of sources can be a serious problem for the accurate and unbiased measurement of fluxes and colours. Methods: t-phot can be considered as the next generation to tfit, providing significant improvements over and above it and other similar codes (e.g. convphot). t-phot gathers data from a high-resolution image of a region of the sky, and uses this information (source positions and morphologies) to obtain priors for the photometric analysis of the lower resolution image of the same field. t-phot can handle different types of datasets as input priors, namely i) a list of objects that will be used to obtain cutouts from the real high-resolution image; ii) a set of analytical models (as .fits stamps); iii) a list of unresolved, point-like sources, useful for example for far-infrared (FIR) wavelength domains. Results: By means of simulations and analysis of real datasets, we show that t-phot yields accurate estimations of fluxes within the intrinsic uncertainties of the method, when systematic errors are taken into account (which can be done thanks to a flagging code given in the output). t-phot is many times faster than similar codes like tfit and convphot (up to hundreds, depending on the problem and the method adopted), whilst at the same time being more robust and more versatile. This makes it an excellent choice for the analysis of large datasets

  3. Different images of science

    DEFF Research Database (Denmark)

    Davidsson, Eva

    express and what consequences follow these when planning and constructing new exhibitions? And in what ways do sponsors affect the content and the design of exhibitions? The purpose of this thesis is to investigate what assumptions and factors affect the final content and design of exhibitions....... The most common image was the usefulness of science which displays science in an unproblematic and single-dimensioned way. In order to explore what underlying assumptions and factors which affect how science is constituted, 17 staff members who worked with planning and constructing new exhibitions...... was interviewed. The data collection also involved participant observation and a focus group interview. The results indicated that staff members' ideas about the nature of science do not seem to have a decisive effect on what scientific aspects they choose to display in exhibitions. When it comes to staff members...

  4. Convolution kernels for multi-wavelength imaging

    Science.gov (United States)

    Boucaud, A.; Bocchio, M.; Abergel, A.; Orieux, F.; Dole, H.; Hadj-Youcef, M. A.

    2016-12-01

    Astrophysical images issued from different instruments and/or spectral bands often require to be processed together, either for fitting or comparison purposes. However each image is affected by an instrumental response, also known as point-spread function (PSF), that depends on the characteristics of the instrument as well as the wavelength and the observing strategy. Given the knowledge of the PSF in each band, a straightforward way of processing images is to homogenise them all to a target PSF using convolution kernels, so that they appear as if they had been acquired by the same instrument. We propose an algorithm that generates such PSF-matching kernels, based on Wiener filtering with a tunable regularisation parameter. This method ensures all anisotropic features in the PSFs to be taken into account. We compare our method to existing procedures using measured Herschel/PACS and SPIRE PSFs and simulated JWST/MIRI PSFs. Significant gains up to two orders of magnitude are obtained with respect to the use of kernels computed assuming Gaussian or circularised PSFs. A software to compute these kernels is available at https://github.com/aboucaud/pypher

  5. Different source image fusion based on FPGA

    Science.gov (United States)

    Luo, Xiao; Piao, Yan

    2016-03-01

    The fusion technology of video image is to make the video obtained by different image sensors complementary to each other by some technical means, so as to obtain the video information which is rich in information and suitable for the human eye system. Infrared cameras in harsh environments such as when smoke, fog and low light situations penetrating power, but the ability to obtain the details of the image is poor, does not meet the human visual system. Single visible light imaging can be rich in detail, high resolution images and for the visual system, but the visible image easily affected by the external environment. Infrared image and visible image fusion process involved in the video image fusion algorithm complexity and high calculation capacity, have occupied more memory resources, high clock rate requirements, such as software, c ++, c, etc. to achieve more, but based on Hardware platform less. In this paper, based on the imaging characteristics of infrared images and visible light images, the software and hardware are combined to obtain the registration parameters through software matlab, and the gray level weighted average method is used to implement the hardware platform. Information fusion, and finally the fusion image can achieve the goal of effectively improving the acquisition of information to increase the amount of information in the image.

  6. THz polarization difference imaging of aqueous targets

    Science.gov (United States)

    Sung, Shijun; Bajwa, Neha; Ramirez, Lucia; Grundfest, Warren; Taylor, Zachary

    2015-08-01

    This paper describes the basic design, implementation, and testing of a polarization difference imaging system for use on aqueous targets. The ultimate performance limitation of THz imaging in many active areas of research is clutter from surface geometry. While the signal to nose ratio (SNR) of standard THz imaging systems is quite large, the signal to clutter ratio (SCR) often faced in an imaging application is orders of magnitude lower and, in many cases, lower than the contrast to noise (CNR) resulting in imagery where the contrast mechanism of interest does not significantly contribute to the overall observed contrast. To overcome these limitations we develop a system that uses a circularly polarized source and linearly polarized detectors to acquire images of transverse electric (TE) and transverse magnetic (TM) reflectivities of the target over the same field of view. Geletin based tissue mimicking phantoms are fabricated with spatially varying water content and modified with a range of surface topologies and surface roughness. TE and TM images are combined to yield self-calibrated clutter-suppressed images. The resulting image indicates that the imaging field clutter affected both polarization channels nearly equally allowing the system to resolve differences in phantom water content. This design is a step toward windowless THz imaging capability critical for clinical translation where patient imaging is dominated by clutter.

  7. Accuracy assessment between different image classification ...

    African Journals Online (AJOL)

    What image classification does is to assign pixel to a particular land cover and land use type that has the most similar spectral signature. However, there are possibilities that different methods or algorithms of image classification of the same data set could produce appreciable variant results in the sizes, shapes and areas of ...

  8. Body image in different periods of adolescence

    OpenAIRE

    Valter Paulo N. Miranda; Maria Aparecida Conti; Pedro Henrique B. de Carvalho; Ronaldo Rocha Bastos; Ferreira,Maria Elisa C.

    2014-01-01

    Objective: To analyze body image in different periods of adolescence. Methods: This cross-sectional study enrolled students aged ten to 19 years old of public schools in small districts of Minas Gerais, Southeast Brazil. The Body Shape Questionnaire (BSQ), the Body Dissatisfaction Assessment Scale for Teenagers and the Silhouette Scale for Teenagers (SST) were used. Adolescence phases were classified according to the subjects' ages. Weight and height were measured in order to calculate t...

  9. Body image in different periods of adolescence

    Science.gov (United States)

    Miranda, Valter Paulo N.; Conti, Maria Aparecida; de Carvalho, Pedro Henrique B.; Bastos, Ronaldo Rocha; Ferreira, Maria Elisa C.

    2014-01-01

    Objective: To analyze body image in different periods of adolescence. Methods: This cross-sectional study enrolled students aged ten to 19 years old of public schools in small districts of Minas Gerais, Southeast Brazil. The Body Shape Questionnaire (BSQ), the Body Dissatisfaction Assessment Scale for Teenagers and the Silhouette Scale for Teenagers (SST) were used. Adolescence phases were classified according to the subjects' ages. Weight and height were measured in order to calculate the body mass index and the nutritional status. Results were analyzed by logistic regression. Results: The study emolled 531 teenagers (318 females). The average age was 15.6± 2 .2 years and 84.6% were eutrophic. The prevalence of body dissatisfaction varied from 28.9% (BSQ) to 78.9% (SST). Overweight adolescents presented greater dissatisfaction (BSQ: OR 3.66, pbody image was observed among adolescents in small towns of Minas Gerais; however, most of them wished a different silhouette than the current one. The results showed that younger adolescents had higher dissatisfaction than their peers, as well as female and overweighed adolescents. PMID:24676192

  10. Body image in different periods of adolescence

    Directory of Open Access Journals (Sweden)

    Valter Paulo N. Miranda

    2014-03-01

    Full Text Available Objective: To analyze body image in different periods of adolescence. Methods: This cross-sectional study enrolled students aged ten to 19 years old of public schools in small districts of Minas Gerais, Southeast Brazil. The Body Shape Questionnaire (BSQ, the Body Dissatisfaction Assessment Scale for Teenagers and the Silhouette Scale for Teenagers (SST were used. Adolescence phases were classified according to the subjects' ages. Weight and height were measured in order to calculate the body mass index and the nutritional status. Results were analyzed by logistic regression. Results: The study emolled 531 teenagers (318 females. The average age was 15.6± 2 .2 years and 84.6% were eutrophic. The prevalence of body dissatisfaction varied from 28.9% (BSQ to 78.9% (SST. Overweight adolescents presented greater dissatisfaction (BSQ: OR 3.66, p<0.001; SST: OR 4.108, p<0.001. Dissatisfaction also occurred for females and those at the early adolescence (p<0.05. Conclusions: A low prevalence of dissatisfaction with the body image was observed among adolescents in small towns of Minas Gerais; however, most of them wished a different silhouette than the current one. The results showed that younger adolescents had higher dissatisfaction than their peers, as well as female and overweighed adolescents.

  11. Body image in different periods of adolescence.

    Science.gov (United States)

    Miranda, Valter Paulo N; Conti, Maria Aparecida; de Carvalho, Pedro Henrique B; Bastos, Ronaldo Rocha; Ferreira, Maria Elisa C

    2014-03-01

    To analyze body image in different periods of adolescence. This cross-sectional study enrolled students aged ten to 19 years old of public schools in small districts of Minas Gerais, Southeast Brazil. The Body Shape Questionnaire (BSQ), the Body Dissatisfaction Assessment Scale for Teenagers and the Silhouette Scale for Teenagers (SST) were used. Adolescence phases were classified according to the subjects' ages. Weight and height were measured in order to calculate the body mass index and the nutritional status. Results were analyzed by logistic regression. The study emolled 531 teenagers (318 females). The average age was 15.6±2 .2 years and 84.6% were eutrophic. The prevalence of body dissatisfaction varied from 28.9% (BSQ) to 78.9% (SST). Overweight adolescents presented greater dissatisfaction (BSQ: OR 3.66, pbody image was observed among adolescents in small towns of Minas Gerais; however, most of them wished a different silhouette than the current one. The results showed that younger adolescents had higher dissatisfaction than their peers, as well as female and overweighed adolescents.

  12. Perceptual evaluation of different image fusion schemes

    NARCIS (Netherlands)

    Toet, A.; IJspeert, J.K.

    2001-01-01

    Human perceptual performance was tested with images of nighttime outdoor scenes. The scenes were registered both with a dual band (visual and near infrared) image intensified low-light CCD camera (DII) and with a thermal middle wavelength band (3-5 μm) infrared (IR) camera. Fused imagery was

  13. Perceptual evaluation of different image fusion schemes

    NARCIS (Netherlands)

    Toet, A.; Franken, E.M.

    2003-01-01

    Human scene recognition performance was tested with images of night-time outdoor scenes. The scenes were registered both with a dual band (visual and near infrared) image intensified low-light CCD camera (DII) and with a thermal middle wavelength band (3–5 mm) infrared (IR) camera. Fused imagery was

  14. Image quality and dose differences caused by vendor-specific image processing of neonatal radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Sensakovic, William F.; O' Dell, M.C.; Letter, Haley; Kohler, Nathan; Rop, Baiywo; Cook, Jane; Logsdon, Gregory; Varich, Laura [Florida Hospital, Imaging Administration, Orlando, FL (United States)

    2016-10-15

    Image processing plays an important role in optimizing image quality and radiation dose in projection radiography. Unfortunately commercial algorithms are black boxes that are often left at or near vendor default settings rather than being optimized. We hypothesize that different commercial image-processing systems, when left at or near default settings, create significant differences in image quality. We further hypothesize that image-quality differences can be exploited to produce images of equivalent quality but lower radiation dose. We used a portable radiography system to acquire images on a neonatal chest phantom and recorded the entrance surface air kerma (ESAK). We applied two image-processing systems (Optima XR220amx, by GE Healthcare, Waukesha, WI; and MUSICA{sup 2} by Agfa HealthCare, Mortsel, Belgium) to the images. Seven observers (attending pediatric radiologists and radiology residents) independently assessed image quality using two methods: rating and matching. Image-quality ratings were independently assessed by each observer on a 10-point scale. Matching consisted of each observer matching GE-processed images and Agfa-processed images with equivalent image quality. A total of 210 rating tasks and 42 matching tasks were performed and effective dose was estimated. Median Agfa-processed image-quality ratings were higher than GE-processed ratings. Non-diagnostic ratings were seen over a wider range of doses for GE-processed images than for Agfa-processed images. During matching tasks, observers matched image quality between GE-processed images and Agfa-processed images acquired at a lower effective dose (11 ± 9 μSv; P < 0.0001). Image-processing methods significantly impact perceived image quality. These image-quality differences can be exploited to alter protocols and produce images of equivalent image quality but lower doses. Those purchasing projection radiography systems or third-party image-processing software should be aware that image

  15. Image quality and dose differences caused by vendor-specific image processing of neonatal radiographs.

    Science.gov (United States)

    Sensakovic, William F; O'Dell, M Cody; Letter, Haley; Kohler, Nathan; Rop, Baiywo; Cook, Jane; Logsdon, Gregory; Varich, Laura

    2016-10-01

    Image processing plays an important role in optimizing image quality and radiation dose in projection radiography. Unfortunately commercial algorithms are black boxes that are often left at or near vendor default settings rather than being optimized. We hypothesize that different commercial image-processing systems, when left at or near default settings, create significant differences in image quality. We further hypothesize that image-quality differences can be exploited to produce images of equivalent quality but lower radiation dose. We used a portable radiography system to acquire images on a neonatal chest phantom and recorded the entrance surface air kerma (ESAK). We applied two image-processing systems (Optima XR220amx, by GE Healthcare, Waukesha, WI; and MUSICA(2) by Agfa HealthCare, Mortsel, Belgium) to the images. Seven observers (attending pediatric radiologists and radiology residents) independently assessed image quality using two methods: rating and matching. Image-quality ratings were independently assessed by each observer on a 10-point scale. Matching consisted of each observer matching GE-processed images and Agfa-processed images with equivalent image quality. A total of 210 rating tasks and 42 matching tasks were performed and effective dose was estimated. Median Agfa-processed image-quality ratings were higher than GE-processed ratings. Non-diagnostic ratings were seen over a wider range of doses for GE-processed images than for Agfa-processed images. During matching tasks, observers matched image quality between GE-processed images and Agfa-processed images acquired at a lower effective dose (11 ± 9 μSv; P Image-processing methods significantly impact perceived image quality. These image-quality differences can be exploited to alter protocols and produce images of equivalent image quality but lower doses. Those purchasing projection radiography systems or third-party image-processing software should be aware that image processing can

  16. Science and Different Images of the World

    Directory of Open Access Journals (Sweden)

    Michele Marsonet

    2016-07-01

    They are both intersubjective and non arbitrary. What are, however, these two images, and are they really alternative? Let us note, from the onset, that the two images we just mentioned are both idealizations in the same sense of Max Weber’s “ideal types”. This means that, in order to discover their actual presence, we need having recourse to a good deal of philosophical abstraction. In other words, they are not disclosed by mere empirical recognition. For instance, we live in the commonsense view of the world, and only a complex process of reflection makes us understand that we, as human beings, share a common view of the world, which is in turn determined by the fact that our physical structure bounds us to conceive of reality in a certain way rather than in another. Think about the importance that light, for example, has not only in daily life, but even in our philosophical conceptualization of the world. The story is complicated by the fact that each image has a history, and while the manifest image dates back to pre-history, the scientific image is constantly changing shape.

  17. Performance comparison of different graylevel image fusion schemes through a universal image quality index

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2003-01-01

    We applied a recently introduced universal image quality index Q that quantifies the distortion of a processed image relative to its original version, to assess the performance of different graylevel image fusion schemes. The method is as follows. First, we adopt an original test image as the

  18. Digital image correlation in experimental mechanics and image registration in computer vision: Similarities, differences and complements

    Science.gov (United States)

    Wang, Zhaoyang; Kieu, Hien; Nguyen, Hieu; Le, Minh

    2015-02-01

    Digital image correlation and image registration or matching are among the most widely used techniques in the fields of experimental mechanics and computer vision, respectively. Despite their applications in separate fields, both techniques primarily involve detecting the same physical points in two or more images. In this paper, a brief technical comparison of the two techniques is reviewed, and their similarities and differences as well as complements are presented. It is shown that some concepts from the image registration or matching technique can be applied to the digital image correlation technique to substantially enhance its performance, which can help broaden the applications of digital image correlation in scientific research and engineering practice.

  19. Children's Images of Scientists: Does Grade Level Make a Difference?

    Science.gov (United States)

    Ozel, Murat

    2012-01-01

    The purpose of this study was to assess children's images of scientists by using the Draw-A-Scientist Test (DAST) and to determine if differences in these images exist between grade levels. The DAST was administered to 243 children who were enrolled in kindergarten (aged 6) and grade 3 and 5 (aged 9 and 11). Findings obtained from the study…

  20. Gender differences in inflammatory bowel disease: Explaining body image dissatisfaction.

    Science.gov (United States)

    Trindade, Inês A; Ferreira, Cláudia; Duarte, Cristiana; Pinto-Gouveia, José

    2017-12-01

    The aim of this study was to examine the role of body image problems in the context of inflammatory bowel disease and to explore gender differences in these associations. A sample of inflammatory bowel disease patients (60 males and 140 females) was collected. Findings from a multi-group analysis show that inflammatory bowel disease symptomatology may impact on body image in both male and female patients through the effect of body-image-related cognitive fusion. Body image difficulties in the context of inflammatory bowel disease should not be a neglected dimension in research aiming at understanding the psychosocial effects of inflammatory bowel disease and by health professionals working with these patients.

  1. System for objective assessment of image differences in digital cinema

    Science.gov (United States)

    Fliegel, Karel; Krasula, Lukáš; Páta, Petr; Myslík, Jiří; Pecák, Josef; Jícha, Marek

    2014-09-01

    There is high demand for quick digitization and subsequent image restoration of archived film records. Digitization is very urgent in many cases because various invaluable pieces of cultural heritage are stored on aging media. Only selected records can be reconstructed perfectly using painstaking manual or semi-automatic procedures. This paper aims to answer the question what are the quality requirements on the restoration process in order to obtain acceptably close visual perception of the digitally restored film in comparison to the original analog film copy. This knowledge is very important to preserve the original artistic intention of the movie producers. Subjective experiment with artificially distorted images has been conducted in order to answer the question what is the visual impact of common image distortions in digital cinema. Typical color and contrast distortions were introduced and test images were presented to viewers using digital projector. Based on the outcome of this subjective evaluation a system for objective assessment of image distortions has been developed and its performance tested. The system utilizes calibrated digital single-lens reflex camera and subsequent analysis of suitable features of images captured from the projection screen. The evaluation of captured image data has been optimized in order to obtain predicted differences between the reference and distorted images while achieving high correlation with the results of subjective assessment. The system can be used to objectively determine the difference between analog film and digital cinema images on the projection screen.

  2. INCREASED IMAGE QUALITY BY SYNTHESIZING SPACE PHOTOS WITH DIFFERENT EXPOSURES

    Directory of Open Access Journals (Sweden)

    A. I. Altukhov

    2017-01-01

    Full Text Available Subject of Research. The paper deals withan approach to the image quality improvement of the underlying surface, obtained by space-based facilities in the visible spectrum. The approach is based on the idea of the region image synthesis with different exposures. This enables to increase the dynamic range of image brightness and display bright and poorly lighted places on the result picture. The relevance of the proposed approach is confirmed by simulation results of objects image quality under a variety of lighting conditions. Linear ground resolution is selected as the quality indicator. Main Results. We have carried out behavior analysis of possible changes in the lighting conditions of the underlying surface in the range of onboard equipment swath of spacecraft observation.We have performed calculation of the terrain linear resolution in narrow spectral ranges of visible light for the space image fragments of the underlying surface with different illumination. It was concluded that the quality of satellite images is limited, since the parameters of onboard equipment monitoring are not selected individually for each object detected within the swath. We have proposed an approach to improve the image quality. Practical Relevance. The proposed approach to the processing of the Earth remote sensing data gives the possibility to obtain images suitable for interpretation with account for specific features of illumination area, as well as to improve the dataware accuracy during the survey support and mapping of areas.

  3. Adaptive Image Restoration and Segmentation Method Using Different Neighborhood Sizes

    Directory of Open Access Journals (Sweden)

    Chengcheng Li

    2003-04-01

    Full Text Available The image restoration methods based on the Bayesian's framework and Markov random fields (MRF have been widely used in the image-processing field. The basic idea of all these methods is to use calculus of variation and mathematical statistics to average or estimate a pixel value by the values of its neighbors. After applying this averaging process to the whole image a number of times, the noisy pixels, which are abnormal values, are filtered out. Based on the Tea-trade model, which states that the closer the neighbor, more contribution it makes, almost all of these methods use only the nearest four neighbors for calculation. In our previous research [1, 2], we extended the research on CLRS (image restoration and segmentation by using competitive learning algorithm to enlarge the neighborhood size. The results showed that the longer neighborhood range could improve or worsen the restoration results. We also found that the autocorrelation coefficient was an important factor to determine the proper neighborhood size. We then further realized that the computational complexity increased dramatically along with the enlargement of the neighborhood size. This paper is to further the previous research and to discuss the tradeoff between the computational complexity and the restoration improvement by using longer neighborhood range. We used a couple of methods to construct the synthetic images with the exact correlation coefficients we want and to determine the corresponding neighborhood size. We constructed an image with a range of correlation coefficients by blending some synthetic images. Then an adaptive method to find the correlation coefficients of this image was constructed. We restored the image by applying different neighborhood CLRS algorithm to different parts of the image according to its correlation coefficient. Finally, we applied this adaptive method to some real-world images to get improved restoration results than by using single

  4. Stereo Vision-Based High Dynamic Range Imaging Using Differently-Exposed Image Pair.

    Science.gov (United States)

    Park, Won-Jae; Ji, Seo-Won; Kang, Seok-Jae; Jung, Seung-Won; Ko, Sung-Jea

    2017-06-22

    In this paper, a high dynamic range (HDR) imaging method based on the stereo vision system is presented. The proposed method uses differently exposed low dynamic range (LDR) images captured from a stereo camera. The stereo LDR images are first converted to initial stereo HDR images using the inverse camera response function estimated from the LDR images. However, due to the limited dynamic range of the stereo LDR camera, the radiance values in under/over-exposed regions of the initial main-view (MV) HDR image can be lost. To restore these radiance values, the proposed stereo matching and hole-filling algorithms are applied to the stereo HDR images. Specifically, the auxiliary-view (AV) HDR image is warped by using the estimated disparity between initial the stereo HDR images and then effective hole-filling is applied to the warped AV HDR image. To reconstruct the final MV HDR, the warped and hole-filled AV HDR image is fused with the initial MV HDR image using the weight map. The experimental results demonstrate objectively and subjectively that the proposed stereo HDR imaging method provides better performance compared to the conventional method.

  5. Stereo Vision-Based High Dynamic Range Imaging Using Differently-Exposed Image Pair

    Directory of Open Access Journals (Sweden)

    Won-Jae Park

    2017-06-01

    Full Text Available In this paper, a high dynamic range (HDR imaging method based on the stereo vision system is presented. The proposed method uses differently exposed low dynamic range (LDR images captured from a stereo camera. The stereo LDR images are first converted to initial stereo HDR images using the inverse camera response function estimated from the LDR images. However, due to the limited dynamic range of the stereo LDR camera, the radiance values in under/over-exposed regions of the initial main-view (MV HDR image can be lost. To restore these radiance values, the proposed stereo matching and hole-filling algorithms are applied to the stereo HDR images. Specifically, the auxiliary-view (AV HDR image is warped by using the estimated disparity between initial the stereo HDR images and then effective hole-filling is applied to the warped AV HDR image. To reconstruct the final MV HDR, the warped and hole-filled AV HDR image is fused with the initial MV HDR image using the weight map. The experimental results demonstrate objectively and subjectively that the proposed stereo HDR imaging method provides better performance compared to the conventional method.

  6. Self-image differences as related to body image of students in a middle school.

    Science.gov (United States)

    Anderson, Donna M; Skemp, Karen M

    2012-07-01

    To examine whether gender and ethnic self-image differences exist among Asian and white adolescents within the context of body image. One hundred seventy-seven students in a Midwestern US middle school were surveyed on self-image. Analyzed using 2-way ANOVA by gender and race. Asian students have lower self-image compared to white students, including the subcomponents of self-esteem, identity, and integrity. Asian students have more critical feelings about themselves, base their identities on a few sources rather than on diverse sources, and choose unrealistic standards. However, Asian girls scored better on the image-consciousness subscale.

  7. Comparison of mammogram images using different quantization methods

    Science.gov (United States)

    Chen, E. T. Y.; Lee, James; Nelson, Alan C.

    1993-07-01

    Special devices with higher quantization resolution are needed to display or process most medical images. In this paper, we compare three different quantization approaches for mammogram images in order to process them in 8 bits/pixel resolution. Since microcalcification is one of the most important indications of risk of breast cancer, a simple shift operation (uniform quantization) cannot retain this vital information. Quantization based on the local histogram will give better results but at the price of more computation.

  8. SIMILARITY MEASURE WITH ADAPTIVE LOCAL WINDOW IN DIFFERENT SIZE IMAGES

    OpenAIRE

    KILIÇASLAN, MAHMUT; TANYERİ, UFUK; İNCETAŞ, MÜRSEL OZAN; YAKIŞIR GİRGİN, BURCU; DEMİRCİ, RECEP; ATAKAN, CEMAL

    2017-01-01

    Content based image retrieval methods requiredifferent features such as color, pattern and shape information. Theresearchers also use the data obtained from the image histogram in thiscontext. The histogram information is calculated locally or globally. However,even though they have the same content, local approaches cannot be used inimages with different aspect ratios, and methods that process over the entirepixels cannot always give the desired results. In this study, a new methodbased on t...

  9. Seismic imaging using finite-differences and parallel computers

    Energy Technology Data Exchange (ETDEWEB)

    Ober, C.C. [Sandia National Labs., Albuquerque, NM (United States)

    1997-12-31

    A key to reducing the risks and costs of associated with oil and gas exploration is the fast, accurate imaging of complex geologies, such as salt domes in the Gulf of Mexico and overthrust regions in US onshore regions. Prestack depth migration generally yields the most accurate images, and one approach to this is to solve the scalar wave equation using finite differences. As part of an ongoing ACTI project funded by the US Department of Energy, a finite difference, 3-D prestack, depth migration code has been developed. The goal of this work is to demonstrate that massively parallel computers can be used efficiently for seismic imaging, and that sufficient computing power exists (or soon will exist) to make finite difference, prestack, depth migration practical for oil and gas exploration. Several problems had to be addressed to get an efficient code for the Intel Paragon. These include efficient I/O, efficient parallel tridiagonal solves, and high single-node performance. Furthermore, to provide portable code the author has been restricted to the use of high-level programming languages (C and Fortran) and interprocessor communications using MPI. He has been using the SUNMOS operating system, which has affected many of his programming decisions. He will present images created from two verification datasets (the Marmousi Model and the SEG/EAEG 3D Salt Model). Also, he will show recent images from real datasets, and point out locations of improved imaging. Finally, he will discuss areas of current research which will hopefully improve the image quality and reduce computational costs.

  10. Visualizing color term differences based on images from the web

    Directory of Open Access Journals (Sweden)

    Nobuyuki Umezu

    2017-01-01

    Full Text Available Color terms are used to express light spectrum characteristics captured by human vision, and color naming across languages partition color spaces differently. Such partition differences have been surveyed through several empirical experiments that employ Munsell color chips. We propose a novel visualization method for color terms based on thousands of images collected from query results provided by an image search engines such as Google. A series of experiments was conducted using eight basic color terms in seven languages. Pixel values in the images are counted to form color histograms according to the color pallet used in the world color survey. The visualization results can be summarized as follows: (1 Japanese and Korean color terms have wider distributions in the color space than terms in other languages do and (2 color visualizations for color terms pink and brown are affected by their links to proper nouns.

  11. Recent advances in different modal imaging-guided photothermal therapy.

    Science.gov (United States)

    Chen, Qiwen; Wen, Jia; Li, Hongjuan; Xu, Yongqian; Liu, Fengyu; Sun, Shiguo

    2016-11-01

    Photothermal therapy (PTT) has recently attracted considerable attention owing to its controllable treatment process, high tumour eradication efficiency and minimal side effects on non-cancer cells. PTT can melt cancerous cells by localising tissue hyperthermia induced by internalised therapeutic agents with a high photothermal conversion efficiency under external laser irradiation. Numerous in vitro and in vivo studies have shown the significant potential of PTT to treat tumours in future practical applications. Unfortunately, the lack of visualisation towards agent delivery and internalisation, as well as imaging-guided comprehensive evaluation of therapeutic outcome, limits its further application. Developments in combined photothermal therapeutic nanoplatforms guided by different imaging modalities have compensated for the major drawback of PTT alone, proving PTT to be a promising technique in biomedical applications. In this review, we introduce recent developments in different imaging modalities including single-modal, dual-modal, triple-modal and even multi-modal imaging-guided PTT, together with imaging-guided multi-functional theranostic nanoplatforms. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Optical flow estimation on image sequences with differently exposed frames

    Science.gov (United States)

    Bengtsson, Tomas; McKelvey, Tomas; Lindström, Konstantin

    2015-09-01

    Optical flow (OF) methods are used to estimate dense motion information between consecutive frames in image sequences. In addition to the specific OF estimation method itself, the quality of the input image sequence is of crucial importance to the quality of the resulting flow estimates. For instance, lack of texture in image frames caused by saturation of the camera sensor during exposure can significantly deteriorate the performance. An approach to avoid this negative effect is to use different camera settings when capturing the individual frames. We provide a framework for OF estimation on such sequences that contain differently exposed frames. Information from multiple frames are combined into a total cost functional such that the lack of an active data term for saturated image areas is avoided. Experimental results demonstrate that using alternate camera settings to capture the full dynamic range of an underlying scene can clearly improve the quality of flow estimates. When saturation of image data is significant, the proposed methods show superior performance in terms of lower endpoint errors of the flow vectors compared to a set of baseline methods. Furthermore, we provide some qualitative examples of how and when our method should be used.

  13. Hyperspectral optical imaging of two different species of lepidoptera

    Directory of Open Access Journals (Sweden)

    Vukusic Pete

    2011-01-01

    Full Text Available Abstract In this article, we report a hyperspectral optical imaging application for measurement of the reflectance spectra of photonic structures that produce structural colors with high spatial resolution. The measurement of the spectral reflectance function is exemplified in the butterfly wings of two different species of Lepidoptera: the blue iridescence reflected by the nymphalid Morpho didius and the green iridescence of the papilionid Papilio palinurus. Color coordinates from reflectance spectra were calculated taking into account human spectral sensitivity. For each butterfly wing, the observed color is described by a characteristic color map in the chromaticity diagram and spreads over a limited volume in the color space. The results suggest that variability in the reflectance spectra is correlated with different random arrangements in the spatial distribution of the scales that cover the wing membranes. Hyperspectral optical imaging opens new ways for the non-invasive study and classification of different forms of irregularity in structural colors.

  14. Measuring image quality performance on image versions saved with different file format and compression ratio

    Science.gov (United States)

    Mitjà, Carles; Escofet, Jaume; Bover, Toni

    2012-06-01

    Digitization of existing documents containing images is an important body of work for many archives ranging from individuals to institutional organizations. The methods and file formats used in this digitization is usually a trade off between budget, file volume size and image quality, while not necessarily in this order. The use of most commons and standardized file formats, JPEG and TIFF, prompts the operator to decide the compression ratio that affects both the final file volume size and the quality of the resulting image version. The evaluation of the image quality achieved by a system can be done by means of several measures and methods, being the Modulation Transfer Function (MTF) one of most used. The methods employed by the compression algorithms affect in a different way the two basic features of the image contents, edges and textures. Those basic features are too differently affected by the amount of noise generated at the digitization stage. Therefore, the target used in the measurement should be related with the features usually presents in general imaging. This work presents a comparison between the results obtained by measuring the MTF of images taken with a professional camera system and saved in several file formats compression ratios. In order to accomplish with the needs early stated, the MTF measurement has been done by two separate methods using the slanted edge and dead leaves targets respectively. The measurement results are shown and compared related with the respective file volume size.

  15. Juvenile chronic arthritis and imaging: comparison of different techniques

    Directory of Open Access Journals (Sweden)

    C. Cervini

    2011-09-01

    Full Text Available Objective: The aim of this study was to compare imaging findings obtained with different techniques in a patient with juvenile chronic arthritis. Methods: The patient was a 12 years-old child with a 7-months history of arthritis of the first metatarsophalangeal joint of the right foot. The involved area was explored with the following imaging techniques: X-ray, technetium bone scintigraphy, magnetic resonance, gray-scale and power-Doppler ultrasonography. Results: No abnormalities were detected with conventional X-ray. Scintigraphy showed an abnormal uptake of the radionuclide in the first metatarsophalangeal joint of the right foot. Magnetic resonance without contrast revealed clearly evident features of an active process of synovitis. Ultrasonography was able to detect the presence of joint effusion, synovial proliferation, bone erosion of the first metatarsal head. Power-Doppler examination revealed evident signs of soft tissue hyperemia. Conclusions: Comparative assessment of different imaging techniques in this patient with recent-onset juvenile chronic arthritis indicates that high resolution ultrasonography provides the most detailed evaluation of the joint involvement with respect to the other imaging techniques.

  16. Detection and removal of artifacts in astronomical images

    Science.gov (United States)

    Desai, S.; Mohr, J. J.; Bertin, E.; Kümmel, M.; Wetzstein, M.

    2016-07-01

    Astronomical images from optical photometric surveys are typically contaminated with transient artifacts such as cosmic rays, satellite trails and scattered light. We have developed and tested an algorithm that removes these artifacts using a deep, artifact free, static sky coadd image built up through the median combination of point spread function (PSF) homogenized, overlapping single epoch images. Transient artifacts are detected and masked in each single epoch image through comparison with an artifact free, PSF-matched simulated image that is constructed using the PSF-corrected, model fitting catalog from the artifact free coadd image together with the position variable PSF model of the single epoch image. This approach works well not only for cleaning single epoch images with worse seeing than the PSF homogenized coadd, but also the traditionally much more challenging problem of cleaning single epoch images with better seeing. In addition to masking transient artifacts, we have developed an interpolation approach that uses the local PSF and performs well in removing artifacts whose widths are smaller than the PSF full width at half maximum, including cosmic rays, the peaks of saturated stars and bleed trails. We have tested this algorithm on Dark Energy Survey Science Verification data and present performance metrics. More generally, our algorithm can be applied to any survey which images the same part of the sky multiple times.

  17. Magnetic Resonance Imaging Findings of Different Polymicrogyria Patterns

    Directory of Open Access Journals (Sweden)

    Erkan Gokce

    2012-09-01

    Conclusion: As one of the most common types of developmental cortical malformations, polymicrogyria can be seen in patients who are presented with clinical findings, such as epilepsy, mental motor retardation and spasticity and polymicrogyria may present in very different types. MRI is an effective imaging technique in patients presenting with cortical developmental malformations such as polymicrogyria [J Contemp Med 2012; 2(3.000: 151-157

  18. Combining Different Modalities for 3D Imaging of Biological Objects

    CERN Document Server

    Tsyganov, E; Kulkarni, P; Mason, R; Parkey, R; Seliuonine, S; Shay, J; Soesbe, T; Zhezher, V; Zinchenko, A I

    2005-01-01

    A resolution enhanced NaI(Tl)-scintillator micro-SPECT device using pinhole collimator geometry has been built and tested with small animals. This device was constructed based on a depth-of-interaction measurement using a thick scintillator crystal and a position sensitive PMT to measure depth-dependent scintillator light profiles. Such a measurement eliminates the parallax error that degrades the high spatial resolution required for small animal imaging. This novel technique for 3D gamma-ray detection was incorporated into the micro-SPECT device and tested with a $^{57}$Co source and $^{98m}$Tc-MDP injected in mice body. To further enhance the investigating power of the tomographic imaging different imaging modalities can be combined. In particular, as proposed and shown in this paper, the optical imaging permits a 3D reconstruction of the animal's skin surface thus improving visualization and making possible depth-dependent corrections, necessary for bioluminescence 3D reconstruction in biological objects. ...

  19. Compressive imaging for difference image formation and wide-field-of-view target tracking

    Science.gov (United States)

    Shikhar

    2010-11-01

    Use of imaging systems for performing various situational awareness tasks in military and commercial settings has a long history. There is increasing recognition, however, that a much better job can be done by developing non-traditional optical systems that exploit the task-specific system aspects within the imager itself. In some cases, a direct consequence of this approach can be real-time data compression along with increased measurement fidelity of the task-specific features. In others, compression can potentially allow us to perform high-level tasks such as direct tracking using the compressed measurements without reconstructing the scene of interest. In this dissertation we present novel advancements in feature-specific (FS) imagers for large field-of-view surveillence, and estimation of temporal object-scene changes utilizing the compressive imaging paradigm. We develop these two ideas in parallel. In the first case we show a feature-specific (FS) imager that optically multiplexes multiple, encoded sub-fields of view onto a common focal plane. Sub-field encoding enables target tracking by creating a unique connection between target characteristics in superposition space and the target's true position in real space. This is accomplished without reconstructing a conventional image of the large field of view. System performance is evaluated in terms of two criteria: average decoding time and probability of decoding error. We study these performance criteria as a function of resolution in the encoding scheme and signal-to-noise ratio. We also include simulation and experimental results demonstrating our novel tracking method. In the second case we present a FS imager for estimating temporal changes in the object scene over time by quantifying these changes through a sequence of difference images. The difference images are estimated by taking compressive measurements of the scene. Our goals are twofold. First, to design the optimal sensing matrix for taking

  20. Racial differences in pelvic anatomy by magnetic resonance imaging.

    Science.gov (United States)

    Handa, Victoria L; Lockhart, Mark E; Fielding, Julia R; Bradley, Catherine S; Brubaker, Linda; Cundiff, Geoffrey W; Ye, Wen; Richter, Holly E

    2008-04-01

    To use static and dynamic magnetic resonance imaging (MRI) to compare dimensions of the bony pelvis and soft tissue structures in a sample of African-American and white women. This study used data from 234 participants in the Childbirth and Pelvic Symptoms Imaging Study, a cohort study of 104 primiparous women with an obstetric anal sphincter tear, 94 who delivered vaginally without a recognized anal sphincter tear and 36 who underwent by cesarean delivery without labor. Race was self-reported. At 6-12 months postpartum, rapid acquisition T2-weighted pelvic MRIs were obtained. Bony and soft tissue dimensions were measured and compared between white and African-American participants using analysis of variance, while controlling for delivery type and age. The pelvic inlet was wider among 178 white women than 56 African-American women (10.7+/-0.7 cm compared with 10.0.+0.7 cm, Ppelvic floor mobility than white women. This difference was not observed among women who had sustained an obstetric sphincter tear. White women have a wider pelvic inlet, wider outlet, and shallower anteroposterior outlet than African-American women. In addition, after vaginal delivery, white women demonstrate less pelvic floor mobility. These differences may contribute to observed racial differences in obstetric outcomes and to the development of pelvic floor disorders.

  1. Characteristics of different frequency ranges in scanning electron microscope images

    Energy Technology Data Exchange (ETDEWEB)

    Sim, K. S., E-mail: kssim@mmu.edu.my; Nia, M. E.; Tan, T. L.; Tso, C. P.; Ee, C. S. [Faculty of Engineering and Technology, Multimedia University, 75450 Melaka (Malaysia)

    2015-07-22

    We demonstrate a new approach to characterize the frequency range in general scanning electron microscope (SEM) images. First, pure frequency images are generated from low frequency to high frequency, and then, the magnification of each type of frequency image is implemented. By comparing the edge percentage of the SEM image to the self-generated frequency images, we can define the frequency ranges of the SEM images. Characterization of frequency ranges of SEM images benefits further processing and analysis of those SEM images, such as in noise filtering and contrast enhancement.

  2. Abdominal MR imaging using a HASTE sequence : image comparison on the different echo times

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kwang Bo; Lee, Moon Gyu; Lim, Tae Hwan; Jeong, Yoong Ki; Ha, Hyun Kwon; Kim, Pyo Nyun; Auh, Yong Ho [Ulsan Univ. College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    1999-11-01

    To determine the optimal parameters of abdominal HASTE imaging by means of a comparison of intermediate and long TE (echo time). We evaluated 30 consecutive patients who had undergone liver MR during a three-month period. Twelve patients were diagnosed as normal, four as having liver cirrhosis, and 14 were found to be suffering form hepatic hemangioma. On the basis of measured signal intensity of the liver, spleen, pancreas and gallbladder, and of fat, muscle, hemangioma, and background, we calculated the ratios of signal to noise (S/N), signal difference to noise (SD/N), and signal intensity (SI). Image quality was compared using these three ratios, and using two HASTE sequences with TEs of 90 msec and 134 msec, images were qualitatively evaluated. S/N ratio of the liver was higher when TE was 90 msec(p<.05), though S/N, SD/N and SI rations of the spleen, gallbladder, and pancreas-and of hemangiom-were higher when TE was 134 msec (p<.05). However, in muscle, all these three ratios were higher at a TE of 90 msec. SD/N ratio and SI of fat were higher at a TE of 134 msec. Overall image quality was better at a TE of 134 msec than at one of 90msec. A HASTE sequence with a TE of 134msec showed greater tissue contrast and stronger T2-weighted images than one with a TE of 90msec.

  3. Evaluation of Lip Prints on Different Supports Using a Batch Image Processing Algorithm and Image Superimposition.

    Science.gov (United States)

    Herrera, Lara Maria; Fernandes, Clemente Maia da Silva; Serra, Mônica da Costa

    2018-01-01

    This study aimed to develop and to assess an algorithm to facilitate lip print visualization, and to digitally analyze lip prints on different supports, by superimposition. It also aimed to classify lip prints according to sex. A batch image processing algorithm was developed, which facilitated the identification and extraction of information about lip grooves. However, it performed better for lip print images with a uniform background. Paper and glass slab allowed more correct identifications than glass and the both sides of compact disks. There was no significant difference between the type of support and the amount of matching structures located in the middle area of the lower lip. There was no evidence of association between types of lip grooves and sex. Lip groove patterns of type III and type I were the most common for both sexes. The development of systems for lip print analysis is necessary, mainly concerning digital methods. © 2017 American Academy of Forensic Sciences.

  4. The Influence of Different Technique Factors on Image Quality for Chest Radiographys: Application of the Recent CEC Image Quality Criteria

    Energy Technology Data Exchange (ETDEWEB)

    Lanhede, B.; Tingberg, A.; Maansson, L.G.; Kheddache, S.; Widell, M.; Bjoerneld, L.; Sund, P.; Almen, A.; Besjakov, J.; Mattsson, S.; Zankl, M.; Panzer, W.; Herrmann, C

    2000-07-01

    The aim of this work was to evaluate and possibly improve the CEC image criteria for radiographic chest images. Chest images of healthy volunteers were acquired using different technique factors. The image criteria were used as a tool to discriminate between the different images. The technique factors were chosen so that the image quality would differ slightly. Four different technique parameters, each with two possible settings used in clinical practice today, were used: tube voltage, 102 and 141 kV; screen-film speed, 160 and 320; maximum optical density in the parenchyma, 1.3 and 1.8; method for scatter reduction, air gap and moving grid. The results showed that the image criteria were able to distinguish different technique groups. Optical density 1.8 was better than 1.3 independent of the other parameters. No difference was seen for screen-film speed. No correlation was seen between the ranking of the systems and patient dose. (author)

  5. Comparison between different encoding schemes for synthetic aperture imaging

    DEFF Research Database (Denmark)

    Nikolov, Svetoslav; Jensen, Jørgen Arendt

    2002-01-01

    Synthetic transmit aperture ultrasound (STAU) imaging can create images with as low as 2 emissions, making it attractive for 3D real-time imaging. Two are the major problems to be solved: (1) complexity of the hardware involved, and (2) poor image quality due to low signal to noise ratio (SNR). We...... have solved the first problem by building a scanner capable of acquiring data using STAU in real-time. The SNR is increased by using encoded signals, which make it possible to send more energy in the body, while reserving the spatial and contrast resolution. The performance of temporal, spatial...

  6. Imaging of primary bone tumors in veterinary medicine: which differences?

    Science.gov (United States)

    Vanel, Maïa; Blond, Laurent; Vanel, Daniel

    2013-12-01

    Veterinary medicine is most often a mysterious world for the human doctors. However, animals are important for human medicine thanks to the numerous biological similarities. Primary bone tumors are not uncommon in veterinary medicine and especially in small domestic animals as dogs and cats. As in human medicine, osteosarcoma is the most common one and especially in the long bones extremities. In the malignant bone tumor family, chondrosarcoma, fibrosarcoma and hemangiosarcoma are following. Benign bone tumors as osteoma, osteochondroma and bone cysts do exist but are rare and of little clinical significance. Diagnostic modalities used depend widely on the owner willing to treat his animal. Radiographs and bone biopsy are the standard to make a diagnosis but CT, nuclear medicine and MRI are more an more used. As amputation is treatment number one in appendicular bone tumor in veterinary medicine, this explains on the one hand why more recent imaging modalities are not always necessary and on the other hand, that prognostic on large animals is so poor that it is not much studied. Chemotherapy is sometimes associated with the surgery procedure, depending on the aggressivity of the tumor. Although, the strakes differs a lot between veterinary and human medicine, biological behavior are almost the same and should led to a beneficial team work between all. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  7. Imaging of primary bone tumors in veterinary medicine: Which differences?

    Energy Technology Data Exchange (ETDEWEB)

    Vanel, Maïa, E-mail: maiavanel@yahoo.fr [Diagnostic Imaging Department, Faculty of Veterinary Medicine, University of Montreal, 3200 Rue Sicotte, PO Box 5000, Saint-Hyacinthe, QC (Canada); Blond, Laurent [Diagnostic Imaging Department, Faculty of Veterinary Medicine, University of Montreal, 3200 Rue Sicotte, PO Box 5000, Saint-Hyacinthe, QC (Canada); Vanel, Daniel [The Rizzoli Institute, Via del Barbiano 1-10, 40136, Bologna (Italy)

    2013-12-01

    Veterinary medicine is most often a mysterious world for the human doctors. However, animals are important for human medicine thanks to the numerous biological similarities. Primary bone tumors are not uncommon in veterinary medicine and especially in small domestic animals as dogs and cats. As in human medicine, osteosarcoma is the most common one and especially in the long bones extremities. In the malignant bone tumor family, chondrosarcoma, fibrosarcoma and hemangiosarcoma are following. Benign bone tumors as osteoma, osteochondroma and bone cysts do exist but are rare and of little clinical significance. Diagnostic modalities used depend widely on the owner willing to treat his animal. Radiographs and bone biopsy are the standard to make a diagnosis but CT, nuclear medicine and MRI are more an more used. As amputation is treatment number one in appendicular bone tumor in veterinary medicine, this explains on the one hand why more recent imaging modalities are not always necessary and on the other hand, that pronostic on large animals is so poor that it is not much studied. Chemotherapy is sometimes associated with the surgery procedure, depending on the agressivity of the tumor. Although, the strakes differs a lot between veterinary and human medicine, biological behavior are almost the same and should led to a beneficial team work between all.

  8. Rotating Scheimpflug Imaging Indices in Different Grades of Keratoconus

    Directory of Open Access Journals (Sweden)

    Sherine S. Wahba

    2016-01-01

    Full Text Available Purpose. To evaluate accuracy of various Keratoconus (KC screening indices, in relation to Topographic Keratoconus (TKC grading. Setting. Al Watany Eye Hospital, Cairo, Egypt. Methods. Data of 103 normal (group 1 and 73 KC eyes (group 2, imaged by Pentacam (branded as Allegro Oculyzer, were analysed. Group 2 was divided into 2a: 14 eyes (TKC = 1, early KC, 2b: 25 eyes (TKC = 1 to 2 or 2, moderate KC, and 2c: 34 eyes (TKC = 2 to 3 up to 4, severe KC. Participants were followed up for six years to confirm diagnosis. Area under the receiver operating characteristic curve (AUROC was calculated for evaluated curvature, elevation, and pachymetry indices with various reference shapes at different diameters. Results. When comparing normal to KC eyes, ten indices had significantly higher AUROC. Only five of them had significantly higher AUROC in early KC compared to normal corneas: Pachymetry Progression Index- (PPI- Maximum (Max, Ambrósio’s Relational Thickness- (ART- Max, PPI-Max minus PPI-Minimum (Min, central corneal thickness (CCT, and diagonal decentration of thinnest point from the apex (AUROC = 0.690, 0.690, 0.687, 0.683, and 0.674, resp.. Conclusion. Generally, ten pachymetry and elevation-based indices had significantly higher AUROC. Five indices had statistically significant high AUROC when comparing early KC to normal corneas.

  9. Goblet cell density estimate differences in impression cytology samples varies with different magnification of images.

    Science.gov (United States)

    Doughty, Michael J

    2017-12-04

    To assess the impact of using different microscope magnifications for the goblet cell density (GCD) estimates from conjunctival impression cytology (CIC) samples from healthy individuals METHODS: In a prospective study, CIC specimens were collected from the superior bulbar conjunctiva (12 o'clock, 5mm from limbus) of 20 adult subjects (average age 22 years) onto Millicell-CM membranes and Giemsa stained. A region from each CIC filter containing reasonably high numbers of goblet cells was imaged by light microscopy at a final magnification of 400X and then the same region assessed at 200X and then 100X. The images were enlarged, the goblet cells marked and counted and GCD values/sq mm calculated. The mean GCD estimates at 400X magnification, 200X and 100X were 644±180, 405±72 and 365±81 cells/sq mm respectively, and these values were statistically different (pmicroscope field (HPF) that appears to include a moderate number of goblet cells will have a probability (by at least 20:1) that the GCD estimates will likely be higher compared to those at 200X or 100X, and the probability for higher GCD values is at least 15:1 comparing assessments made at 200X to 100X. Investigators should use only one magnification, with that of a medium power field (200X final magnification) likely being the most useful. Copyright © 2017 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  10. Determining Tidal Phase Differences from X-Band Radar Images

    Science.gov (United States)

    Newman, Kieran; Bell, Paul; Brown, Jennifer; Plater, Andrew

    2017-04-01

    Introduction Previous work by Bell et. al. (2016) has developed a method using X-band marine radar to measure intertidal bathymetry, using the waterline as a level over a spring-neap tidal cycle. This has been used in the Dee Estuary to give a good representation of the bathymetry in the area. However, there are some sources of inaccuracy in the method, as a uniform spatial tidal signal is assumed over the entire domain. Motivation The method used by Bell et. al. (2016) applies a spatially uniform tidal signal to the entire domain. This fails to account for fine-scale variations in water level and tidal phase. While methods are being developed to account for small-scale water level variations using high resolution modelling, a method to determine tidal phase variations directly from the radar intensity images could be advantageous operationally. Methods The tidal phase has been computed using two different methods, with hourly averaged images from 2008. In the first method, the cross-correlation between each raw pixel time series and a tidal signal at a number of lags is calculated, and the lag with the highest correlation to the pixel series is recorded. For the second method, the same method of correlation is used on signals generated by tracking movement of buoys, which show up strongly in the radar image as they move on their moorings with the tidal currents. There is a broad agreement between the two methods, but validation is needed to determine the relative accuracy. The phase has also been calculated using a Fourier decomposition, and agrees broadly with the above methods. Work also needs to be done to separate areas where the recorded phase is due to tidal current (mostly subtidal areas) or due to elevation (mostly the wetting/drying signal in intertidal areas), by classifying radar intensities by the phases and amplitudes of the tides. Filtering out signal variations due to wind strength and attenuation of the radar signal will also be applied. Validation

  11. Body Image Dissatisfaction and Distortion, Steroid Use, and Sex Differences in College Age Bodybuilders.

    Science.gov (United States)

    Peters, Mark Anthony; Phelps, LeAddelle

    2001-01-01

    Compares college age bodybuilders by sex and steroid intake on two variables: body image dissatisfaction and body image distortion. Results reveal only a significant effect for gender on body distortion. No steroid-use differences were apparent for either body image dissatisfaction or body image distortion. Analyses indicate that female…

  12. Fundamental performance differences of CMOS and CCD imagers: part V

    Science.gov (United States)

    Janesick, James R.; Elliott, Tom; Andrews, James; Tower, John; Pinter, Jeff

    2013-02-01

    Previous papers delivered over the last decade have documented developmental progress made on large pixel scientific CMOS imagers that match or surpass CCD performance. New data and discussions presented in this paper include: 1) a new buried channel CCD fabricated on a CMOS process line, 2) new data products generated by high performance custom scientific CMOS 4T/5T/6T PPD pixel imagers, 3) ultimate CTE and speed limits for large pixel CMOS imagers, 4) fabrication and test results of a flight 4k x 4k CMOS imager for NRL's SoloHi Solar Orbiter Mission, 5) a progress report on ultra large stitched Mk x Nk CMOS imager, 6) data generated by on-chip sub-electron CDS signal chain circuitry used in our imagers, 7) CMOS and CMOSCCD proton and electron radiation damage data for dose levels up to 10 Mrd, 8) discussions and data for a new class of PMOS pixel CMOS imagers and 9) future CMOS development work planned.

  13. Comparing different ultrasound imaging methods for breast cancer detection

    NARCIS (Netherlands)

    Ozmen, N.; Dapp, R.; Zapf, M.; Gemmeke, H.; Ruiter, N.V.; Van Dongen, K.W.A.

    2015-01-01

    Ultrasound is frequently used to evaluate suspicious masses in breasts. These evaluations could be improved by taking advantage of advanced imaging algorithms, which become feasible for low frequencies if accurate knowledge about the phase and amplitude of the wave field illuminating the volume of

  14. Gender Differences in Effects of Mood on Body Image.

    Science.gov (United States)

    Barber, Nigel

    2001-01-01

    Investigated the relationship between experimental mood alteration and body image among college students who experienced mood induction by reading self-descriptive statements. Analysis of participant responses indicated that the more elated they felt, the lighter they felt, regardless of gender. However, the manipulation did not alter body ideal…

  15. Reversible Watermarking Using IWT For DifferentImages

    OpenAIRE

    Gajanan S. Pande; N. S. Narawade; Anant B. Andhale; Sonali D. Wable

    2012-01-01

    Wavelets were developed independently by mathematicians, quantum physicists, electrical engineers and geologists, but collaborations among these fields during the last decade have led to new and varied applications. What are wavelets, and why might they be useful to you? This paper will tell you how Reversible watermarking has found a huge surge of experimentation in its domain in past decade as the need of recovering the original work image after extracting the watermark arises in various ap...

  16. Precise diagnosis in different scenarios using photoacoustic and fluorescence imaging with dual-modality nanoparticles

    Science.gov (United States)

    Peng, Dong; Du, Yang; Shi, Yiwen; Mao, Duo; Jia, Xiaohua; Li, Hui; Zhu, Yukun; Wang, Kun; Tian, Jie

    2016-07-01

    Photoacoustic imaging and fluorescence molecular imaging are emerging as important research tools for biomedical studies. Photoacoustic imaging offers both strong optical absorption contrast and high ultrasonic resolution, and fluorescence molecular imaging provides excellent superficial resolution, high sensitivity, high throughput, and the ability for real-time imaging. Therefore, combining the imaging information of both modalities can provide comprehensive in vivo physiological and pathological information. However, currently there are limited probes available that can realize both fluorescence and photoacoustic imaging, and advanced biomedical applications for applying this dual-modality imaging approach remain underexplored. In this study, we developed a dual-modality photoacoustic-fluorescence imaging nanoprobe, ICG-loaded Au@SiO2, which was uniquely designed, consisting of gold nanorod cores and indocyanine green with silica shell spacer layers to overcome fluorophore quenching. This nanoprobe was examined by both PAI and FMI for in vivo imaging on tumor and ischemia mouse models. Our results demonstrated that the nanoparticles can specifically accumulate at the tumor and ischemic areas and be detected by both imaging modalities. Moreover, this dual-modality imaging strategy exhibited superior advantages for a precise diagnosis in different scenarios. The new nanoprobe with the dual-modality imaging approach holds great potential for diagnosis and stage classification of tumor and ischemia related diseases.Photoacoustic imaging and fluorescence molecular imaging are emerging as important research tools for biomedical studies. Photoacoustic imaging offers both strong optical absorption contrast and high ultrasonic resolution, and fluorescence molecular imaging provides excellent superficial resolution, high sensitivity, high throughput, and the ability for real-time imaging. Therefore, combining the imaging information of both modalities can provide

  17. Harmonisation of the appearance of digital radiographs from different vendors by means of common external image processing.

    Science.gov (United States)

    Larsson, Lars; Båth, Magnus; Engman, Eva-Lena; Månsson, Lars Gunnar

    2010-01-01

    The aim of the present study was to evaluate the use of common external image processing to compensate for differences in appearance between digital X-ray images from different vendors. Twenty posteroanterior chest radiographs were collected from each of three different modalities from different vendors (GE, Siemens and Canon) with vendor-specific image processing applied. The images were also extracted with neutral process parameters and processed with external image-processing software. Six experienced radiologists rated the quality and the similarity of the images with the original Siemens images. The externally processed GE images were rated of higher quality than the original GE images and more similar to the original Siemens images (p images. The externally processed Siemens images were rated of similar quality as the original images. The present study indicates the possibility of using common external image processing to harmonise the appearance of images from different vendors, although the exposure parameters may need to be adjusted for individual vendors.

  18. Integrated NDVI images for Niger 1986-1987. [Normalized Difference Vegetation Index

    Science.gov (United States)

    Harrington, John A., Jr.; Wylie, Bruce K.; Tucker, Compton J.

    1988-01-01

    Two NOAA AVHRR images are presented which provide a comparison of the geographic distribution of an integration of the normalized difference vegetation index (NDVI) for the Sahel zone in Niger for the growing seasons of 1986 and 1987. The production of the images and the application of the images for resource management are discussed. Daily large area coverage with a spatial resolution of 1.1 km at nadir were transformed to the NDVI and geographically registered to produce the images.

  19. Hydrogen Flame Imaging System Soars to New, Different Heights

    Science.gov (United States)

    2002-01-01

    When Judy and Dave Duncan of Auburn, Calif.-based Duncan Technologies Inc. (DTI) developed their color hydrogen flame imaging system in the early 1990's, their market prospects were limited. 'We talked about commercializing the technology in the hydrogen community, but we also looked at commercialization on a much broader aspect. While there were some hydrogen applications, the market was not large enough to suppport an entire company; also, safety issues were a concern,' said Judy Duncan, owner and CEO of Duncan Technologies. Using the basic technology developed under the Small Business Innovation Research Program (SBIR); DTI conducted market research, identified other applications, formulated a plan for next generation development, and implemented a far-reaching marketing strategy. 'We took that technology; reinvested our own funds and energy into a second-generation design on the overall camera electronics and deployed that basic technology intially in a series of what we call multi-spectral cameras; cameras that could image in both the visible range and the infrared,' explains Duncan. 'The SBIR program allowed us to develop the technology to do a 3CCD camera, which very few compaines in the world do, particularly not small companies. The fact that we designed our own prism and specked the coding as we had for the hydrogen application, we were able to create a custom spectral configuration which could support varying types of research and applications.' As a result, Duncan Technologies Inc. of Auburn, Ca., has achieved a milestone $ 1 million in sales.

  20. Imaging FTS: A Different Approach to Integral Field Spectroscopy

    Directory of Open Access Journals (Sweden)

    Laurent Drissen

    2014-01-01

    Full Text Available Imaging Fourier transform spectroscopy (iFTS is a promising, although technically very challenging, option for wide-field hyperspectral imagery. We present in this paper an introduction to the iFTS concept and its advantages and drawbacks, as well as examples of data obtained with a prototype iFTS, SpIOMM, attached to the 1.6 m telescope of the Observatoire du Mont-Mégantic: emission line ratios in the spiral galaxy NGC 628 and absorption line indices in the giant elliptical M87. We conclude by introducing SpIOMM's successor, SITELLE, which will be installed at the Canada-France-Hawaii Telescope in 2014.

  1. Radiometric Normalization of Large Airborne Image Data Sets Acquired by Different Sensor Types

    Science.gov (United States)

    Gehrke, S.; Beshah, B. T.

    2016-06-01

    Generating seamless mosaics of aerial images is a particularly challenging task when the mosaic comprises a large number of im-ages, collected over longer periods of time and with different sensors under varying imaging conditions. Such large mosaics typically consist of very heterogeneous image data, both spatially (different terrain types and atmosphere) and temporally (unstable atmo-spheric properties and even changes in land coverage). We present a new radiometric normalization or, respectively, radiometric aerial triangulation approach that takes advantage of our knowledge about each sensor's properties. The current implementation supports medium and large format airborne imaging sensors of the Leica Geosystems family, namely the ADS line-scanner as well as DMC and RCD frame sensors. A hierarchical modelling - with parameters for the overall mosaic, the sensor type, different flight sessions, strips and individual images - allows for adaptation to each sensor's geometric and radiometric properties. Additional parameters at different hierarchy levels can compensate radiome-tric differences of various origins to compensate for shortcomings of the preceding radiometric sensor calibration as well as BRDF and atmospheric corrections. The final, relative normalization is based on radiometric tie points in overlapping images, absolute radiometric control points and image statistics. It is computed in a global least squares adjustment for the entire mosaic by altering each image's histogram using a location-dependent mathematical model. This model involves contrast and brightness corrections at radiometric fix points with bilinear interpolation for corrections in-between. The distribution of the radiometry fixes is adaptive to each image and generally increases with image size, hence enabling optimal local adaptation even for very long image strips as typi-cally captured by a line-scanner sensor. The normalization approach is implemented in HxMap software. It has been

  2. Adaptable pattern recognition system for discriminating Melanocytic Nevi from Malignant Melanomas using plain photography images from different image databases.

    Science.gov (United States)

    Kostopoulos, Spiros A; Asvestas, Pantelis A; Kalatzis, Ioannis K; Sakellaropoulos, George C; Sakkis, Theofilos H; Cavouras, Dionisis A; Glotsos, Dimitris T

    2017-09-01

    The aim of this study was to propose features that evaluate pictorial differences between melanocytic nevus (mole) and melanoma lesions by computer-based analysis of plain photography images and to design a cross-platform, tunable, decision support system to discriminate with high accuracy moles from melanomas in different publicly available image databases. Digital plain photography images of verified mole and melanoma lesions were downloaded from (i) Edinburgh University Hospital, UK, (Dermofit, 330moles/70 melanomas, under signed agreement), from 5 different centers (Multicenter, 63moles/25 melanomas, publicly available), and from the Groningen University, Netherlands (Groningen, 100moles/70 melanomas, publicly available). Images were processed for outlining the lesion-border and isolating the lesion from the surrounding background. Fourteen features were generated from each lesion evaluating texture (4), structure (5), shape (4) and color (1). Features were subjected to statistical analysis for determining differences in pictorial properties between moles and melanomas. The Probabilistic Neural Network (PNN) classifier, the exhaustive search features selection, the leave-one-out (LOO), and the external cross-validation (ECV) methods were used to design the PR-system for discriminating between moles and melanomas. Statistical analysis revealed that melanomas as compared to moles were of lower intensity, of less homogenous surface, had more dark pixels with intensities spanning larger spectra of gray-values, contained more objects of different sizes and gray-levels, had more asymmetrical shapes and irregular outlines, had abrupt intensity transitions from lesion to background tissue, and had more distinct colors. The PR-system designed by the Dermofit images scored on the Dermofit images, using the ECV, 94.1%, 82.9%, 96.5% for overall accuracy, sensitivity, specificity, on the Multicenter Images 92.0%, 88%, 93.7% and on the Groningen Images 76.2%, 73.9%, 77

  3. Investigation into image quality difference between total variation and nonlinear sparsifying transform based compressed sensing

    Science.gov (United States)

    Dong, Jian; Kudo, Hiroyuki

    2017-03-01

    Compressed sensing (CS) is attracting growing concerns in sparse-view computed tomography (CT) image reconstruction. The most standard approach of CS is total variation (TV) minimization. However, images reconstructed by TV usually suffer from distortions, especially in reconstruction of practical CT images, in forms of patchy artifacts, improper serrate edges and loss of image textures. Most existing CS approaches including TV achieve image quality improvement by applying linear transforms to object image, but linear transforms usually fail to take discontinuities into account, such as edges and image textures, which is considered to be the key reason for image distortions. Actually, discussions on nonlinear filter based image processing has a long history, leading us to clarify that the nonlinear filters yield better results compared to linear filters in image processing task such as denoising. Median root prior was first utilized by Alenius as nonlinear transform in CT image reconstruction, with significant gains obtained. Subsequently, Zhang developed the application of nonlocal means-based CS. A fact is gradually becoming clear that the nonlinear transform based CS has superiority in improving image quality compared with the linear transform based CS. However, it has not been clearly concluded in any previous paper within the scope of our knowledge. In this work, we investigated the image quality differences between the conventional TV minimization and nonlinear sparsifying transform based CS, as well as image quality differences among different nonlinear sparisying transform based CSs in sparse-view CT image reconstruction. Additionally, we accelerated the implementation of nonlinear sparsifying transform based CS algorithm.

  4. 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.

  5. Contribution of polarimetric imaging for the characterization of fibrous surface properties at different scales

    Science.gov (United States)

    Tourlonias, Michel; Bigué, Laurent; Bueno, Marie-Ange

    2010-01-01

    The point in using polarimetric imaging for surface characterization is highlighted in this paper. A method for the evaluation of nonwoven surface properties at microscopic and macroscopic scales is described. This method is based on a polarimetric apparatus and various image processing operations are then performed depending on the studied scale. Polarimetric imaging applied to nonwovens, particularly degree of polarization imaging, highlights texture inhomogeneities. At both scales, image processing techniques were designed to analyze surface zones of different textures. At the macroscopic scale, a basic image processing was developed in order to detect the nonwoven manufacturing process defects. Moreover at the microscopic scale, i.e. at the fiber scale, image processing was adapted to evaluate fiber orientation within nonwovens, which is known to be an important information for mechanical behavior prediction.

  6. Difference Image Analysis: Extension to a Spatially Varying Photometric Scale Factor and Other Considerations

    OpenAIRE

    Bramich, D. M.; Horne, Keith; Albrow, M. D.; Tsapras, Y; Snodgrass, C.; Street, R. A.; Hundertmark, M; Kains, Noe; Ferro, A. Arellano; Jaimes, R. Figuera; Giridhar, Sunetra

    2012-01-01

    We present a general framework for matching the point-spread function (PSF), photometric scaling, and sky background between two images, a subject which is commonly referred to as difference image analysis (DIA). We introduce the new concept of a spatially varying photometric scale factor which will be important for DIA applied to wide-field imaging data in order to adapt to transparency and airmass variations across the field-of-view. Furthermore, we demonstrate how to separately control the...

  7. Gender and Racial/Ethnic Differences in Body Image Development Among College Students

    OpenAIRE

    Gillen, Meghan M.; Lefkowitz, Eva S.

    2011-01-01

    In the present study we used longitudinal methods to examine body image development during the early part of college. Students (N = 390; 54% female) who identified as African American (32%), Latino/a American (27%), and European American (41%) completed surveys during their first, second, and third semesters at college. There were overall gender and racial/ethnic differences in all three aspects of body image, and both stability and change in body image development. Female students’ appearanc...

  8. Differences in selectivity to natural images in early visual areas (V1-V3).

    Science.gov (United States)

    Coggan, David D; Allen, Luke A; Farrar, Oliver R H; Gouws, Andre D; Morland, Antony B; Baker, Daniel H; Andrews, Timothy J

    2017-05-26

    High-level regions of the ventral visual pathway respond more to intact objects compared to scrambled objects. The aim of this study was to determine if this selectivity for objects emerges at an earlier stage of processing. Visual areas (V1-V3) were defined for each participant using retinotopic mapping. Participants then viewed intact and scrambled images from different object categories (bottle, chair, face, house, shoe) while neural responses were measured using fMRI. Our rationale for using scrambled images is that they contain the same low-level properties as the intact objects, but lack the higher-order combinations of features that are characteristic of natural images. Neural responses were higher for scrambled than intact images in all regions. However, the difference between intact and scrambled images was smaller in V3 compared to V1 and V2. Next, we measured the spatial patterns of response to intact and scrambled images from different object categories. We found higher within-category compared to between category correlations for both intact and scrambled images demonstrating distinct patterns of response. Spatial patterns of response were more distinct for intact compared to scrambled images in V3, but not in V1 or V2. These findings demonstrate the emergence of selectivity to natural images in V3.

  9. Differences of perceived image generated through the Web site: Empirical Evidence Obtained in Spanish Destinations

    Directory of Open Access Journals (Sweden)

    Juan Jose Blazquez-Resino

    2016-11-01

    Full Text Available In this paper, a study of the perceived destination image created by promotional Web Pages is expounded in an attempt to identify their differences as generators of destination image in the consumers’ mind. Specifically, it seeks to analyse whether the web sites of different Spanish regions improve the image that consumers have of the destination, identifying their main dimensions and analysing its effect on satisfaction and intentions of the future behaviour of potential visitors. To achieve these objectives and verify the hypotheses, a laboratory experiment was performed, where it was determined what changes are produced in the tourist´s previous image after browsing the tourist webs of three different regions. Moreover, it analyses the differences in the effect of the perceived image on satisfaction and potential visitors´ future behavioural intentions. The results obtained enable us to identify differences in the composition of the perceived image according to the destination, while confirming the significant effect of different perceived image dimensions regarding satisfaction. The results allow managers to gain a better understanding of the effectiveness of their sites from a consumer perspective as well as suggestions to follow in order to achieve greater efficiency in their communication actions in order to improve the motivation of visitors to go to the destination.

  10. Volumetric and two-dimensional image interpretation show different cognitive processes in learners

    NARCIS (Netherlands)

    van der Gijp, Anouk; Ravesloot, Cécile J.; van der Schaaf, Marieke F.; van der Schaaf, Irene C.; Huige, Josephine C B M; Vincken, Koen L.; Ten Cate, Olle Th J; van Schaik, Jan P J

    2015-01-01

    Rationale and Objectives: In current practice, radiologists interpret digital images, including a substantial amount of volumetric images. We hypothesized that interpretation of a stack of a volumetric data set demands different skills than interpretation of two-dimensional (2D) cross-sectional

  11. Volumetric and two-dimensional image interpretation show different cognitive processes in learners

    NARCIS (Netherlands)

    van der Gijp, Anouk|info:eu-repo/dai/nl/413648907; Ravesloot, C.J.|info:eu-repo/dai/nl/362749663; van der Schaaf, Marieke F; van der Schaaf, Irene C|info:eu-repo/dai/nl/29133489X; Huige, Josephine C B M; Vincken, Koen L|info:eu-repo/dai/nl/143101722; Ten Cate, Olle Th J|info:eu-repo/dai/nl/068931204; van Schaik, JPJ|info:eu-repo/dai/nl/070114811

    2015-01-01

    RATIONALE AND OBJECTIVES: In current practice, radiologists interpret digital images, including a substantial amount of volumetric images. We hypothesized that interpretation of a stack of a volumetric data set demands different skills than interpretation of two-dimensional (2D) cross-sectional

  12. Fusion of different modalities of imaging the fist; Fusion d`images de diverses modalites du poignet

    Energy Technology Data Exchange (ETDEWEB)

    Verdenet, J.; Garbuio, P.; Runge, M.; Cardot, J.C. [Medecine Nucleaire, CHU St. Jacques, BESANCON 25030 (France)

    1997-12-31

    The standard radiographical pictures are not able always to bring out the fracture of one of the fist bones. In an early study it was shown that 40% of patients presenting a suspicion of fracture and in which the radio- image was normal, have had a fracture confirmed with quantification by MRI and scintigraphy. The last one does not allow to specify the localization and consequently we developed a code to fusion entirely automatically the radiologic image and the scintigraphic image using no external marker. The code has been installed on a PC and uses the Matlab environment. Starting from the histogram processing the contours are individualized on the interpolated radio- and scinti-images. For matching there are 3 freedom degrees: one of rotation and 2 of translation (in x and y axes). The internal axes of the forearm was chosen to effect the rotation and translation. The forehand thickness, identical for each modality, allows to match properly the images. We have obtained an anatomic image on which the contour and the hyper-fixating zones of the scintigraphy are added. On a set of 100 examinations we observed 38 fractures while the difference between a fracture of the scaphoid and of another fist bone is confirmed in 93% of cases

  13. Comparison of virtual unenhanced CT images of the abdomen under different iodine flow rates.

    Science.gov (United States)

    Li, Yongrui; Li, Ye; Jackson, Alan; Li, Xiaodong; Huang, Ning; Guo, Chunjie; Zhang, Huimao

    2017-01-01

    To assess the effect of varying iodine flow rate (IFR) and iodine concentration on the quality of virtual unenhanced (VUE) images of the abdomen obtained with dual-energy CT. 94 subjects underwent unenhanced and triphasic contrast-enhanced CT scan of the abdomen, including arterial phase, portal venous phase, and delayed phase using dual-energy CT. Patients were randomized into 4 groups with different IFRs or iodine concentrations. VUE images were generated at 70 keV. The CT values, image noise, SNR and CNR of aorta, portal vein, liver, liver lesion, pancreatic parenchyma, spleen, erector spinae, and retroperitoneal fat were recorded. Dose-length product and effective dose for an examination with and without plain phase scan were calculated to assess the potential dose savings. Two radiologists independently assessed subjective image quality using a five-point scale. The Kolmogorov-Smirnov test was used first to test for normal distribution. Where data conformed to a normal distribution, analysis of variance was used to compare mean HU values, image noise, SNRs and CNRs for the 4 image sets. Where data distribution was not normal, a nonparametric test (Kruskal-Wallis test followed by stepwise step-down comparisons) was used. The significance level for all tests was 0.01 (two-sided) to allow for type 2 errors due to multiple testing. The CT numbers (HU) of VUE images showed no significant differences between the 4 groups (p > 0.05) or between different phases within the same group (p > 0.05). VUE images had equal or higher SNR and CNR than true unenhanced images. VUE images received equal or lower subjective image quality scores than unenhanced images but were of acceptable quality for diagnostic use. Calculated dose-length product and estimated dose showed that the use of VUE images in place of unenhanced images would be associated with a dose saving of 25%. VUE images can replace conventional unenhanced images. VUE images are not affected by varying iodine

  14. Comparison of image quality in head CT studies with different dose-reduction strategies

    DEFF Research Database (Denmark)

    Johansen, Jeppe; Nielsen, Rikke; Fink-Jensen, Vibeke

    account to a considerable radiation dose as many patients undergo repeated studies. Therefore, various dose-reduction strategies are applied such as automated tube current and voltage modulation and recently different iterative reconstruction algorithms. However, the trade-off of all dose......-reduction maneuvers is reduction of image quality due to image noise or artifacts. The aim of our study was therefore to find the best diagnostic images with lowest possible dose. We present results of dose- and image quality optimizing strategies of brain CT examinations at our institution. We compare sequential...

  15. Improved image quality and detectability of hypovascular liver metastases on DECT with different adjusted window settings

    Energy Technology Data Exchange (ETDEWEB)

    Altenbernd, Jens; Forsting, Michael; Lauenstein, Thomas; Wetter, Axel [Duisburg-Essen Univ., Essen (Germany). Dept. of Diagnostic and Interventional Radiology and Neuroradiology

    2017-03-15

    To investigate dual-energy CT of hypovascular liver metastases (LMs) with special focus on window settings (WSs). The aim of the study is to investigate the extent to which adapted WSs and the low-energy images of DECT improve the visibility especially of smaller LMs. 30 patients with LMs of colorectal cancer were investigated with DECT of the liver. In each patient contrast-enhanced DECT imaging with portal-venous delay was performed. The total number, mean number and conspicuity (1= excellent - 5 = poor) of LMs were documented on 80-kVp images and virtual 120-kVp images with different WSs (25/200 HU, 50/200, 75/200 HU, 25/350 HU, 50/350 HU, 75/350 HU, 25/500 HU, 50/500 HU, 75/500 HU). The attenuation (HU) of LMs and several anatomic regions and the background noise on 80 kVp images and virtual 120 kVp images were documented. Signal (liver)/noise and liver/LM ratio (SNR/LLMR) were calculated. The total number of LMs depending on size (<1cm, 1-2cm, >2cm) on 80 kVp images and virtual 120 kVp images with previously investigated best and regular WSs were documented. The highest total number, mean number per patient and total number of LMs <1cm were detected with the WS 25/350 HU on 80kVp images (7.0; p = 0.02/218; p = 0.01/64;p<0.001) compared to the WS 75/200 HU on virtual 120 kVp images and the regular WS 50/350 HU on 80 kVp images and virtual 120 kVp images. The best conspicuity of LMs on 80 kVp images was documented with the WS 25/350 HU compared to the best WS on virtual 120 kVp images with 75/200 HU (1.2 vs. 2.5; p = 0.01). HU of normal liver, aorta, SNR and LLMR differed significantly between 80 kVp images and virtual 120 kVp images (128.1 vs. 93.6; < 0.05/192.8 vs. 131.4; < 0.05/10.3 vs. 8.1; p < 0.05/2.8 vs. 2.1; p < 0.05). Low kVp images of DECT datasets are more precise in detecting hypovascular liver metastases than virtual 120 kVp images. Dedicated window settings have a relevant influence on conspicuity.

  16. Are there differences in the attitudinal body image between adolescent anorexia nervosa and bulimia nervosa?

    Science.gov (United States)

    Ruuska, J; Kaltiala-Heino, R; Rantanen, P; Koivisto, A M

    2005-06-01

    Body image dissatisfaction is as well a risk factor for eating disorders (ED) and a central feature of ED. The exact nature of body image in adolescent ED is still debated. This study examined attitudinal body image in adolescent anorexia nervosa (AN) and bulimia nervosa (BN), and the association of age, maturational timing, duration of eating disorder, actual weight and general psychological distress with the attitudinal body image in ED. The study group consisted of an outpatient clinical sample of adolescents attending for assessment because of eating disorders. The attitudinal body image of 57 adolescents (girls) aged 14-21 years was studied at the beginning of the treatment. The attitudes to body shape, body size, appearance, tone and femininity were studied by a Likert format scale and by the body dissatisfaction (BD) and drive for thinness scales (DT) from EDI-2 inventory. Bulimics reported more body image dissatisfaction than anorectics. In multivariate analyses BN and higher general psychological distress had strong associations with body image dissatisfaction. Longer duration of ED and earlier menarche were also associated with negative body image. Attitudinal body image differs between adolescent AN and BN. The psychological distress has a great impact on body image in ED, which should be taken into account in assessment and in treatment interventions.

  17. The effect of different physical and sport activity courses on body image of Costa Rican students

    National Research Council Canada - National Science Library

    Yamileth Chacón-Araya; José Moncada-Jiménez

    2013-01-01

      The purpose of this study was to determine the effect of different types of physical education sport courses on perceived and desired body image in university students from the University of Costa Rica...

  18. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Smoothed Normalized Difference Vegetation Index (NDVI) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Visible Infrared Imaging Radiometer Suite (VIIRS) Smoothed Normalized Difference Vegetation Index (NDVI) from NDE is a weekly product derived from the VIIRS...

  19. Image scanning fluorescence emission difference microscopy based on a detector array.

    Science.gov (United States)

    Li, Y; Liu, S; Liu, D; Sun, S; Kuang, C; Ding, Z; Liu, X

    2017-06-01

    We propose a novel imaging method that enables the enhancement of three-dimensional resolution of confocal microscopy significantly and achieve experimentally a new fluorescence emission difference method for the first time, based on the parallel detection with a detector array. Following the principles of photon reassignment in image scanning microscopy, images captured by the detector array were arranged. And by selecting appropriate reassign patterns, the imaging result with enhanced resolution can be achieved with the method of fluorescence emission difference. Two specific methods are proposed in this paper, showing that the difference between an image scanning microscopy image and a confocal image will achieve an improvement of transverse resolution by approximately 43% compared with that in confocal microscopy, and the axial resolution can also be enhanced by at least 22% experimentally and 35% theoretically. Moreover, the methods presented in this paper can improve the lateral resolution by around 10% than fluorescence emission difference and 15% than Airyscan. The mechanism of our methods is verified by numerical simulations and experimental results, and it has significant potential in biomedical applications. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  20. Individual Differences in Odor Imaging Ability Reflect Differences in Olfactory and Emotional Perception

    National Research Council Canada - National Science Library

    Bensafi, M; Rouby, C

    2007-01-01

    .... Based on self-reported measures, these results suggest that, like olfactory perception, the mental imagery of smells is related to emotion and that, beyond their differences in vividness, good...

  1. Study of CT head scans using different voltages: image quality evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco de Freitas C, I.; Prata M, A. [Centro Federal de Educacao Tecnologica de Minas Gerais, Centro de Engenharia Biomedica, Av. Amazonas 5253, 30421-169 Nova Suica, Belo Horizonte, Minas Gerais (Brazil); Alonso, T. C. [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Av. Pte. Antonio Carlos 6627, 31270-901 Pampulha, Belo Horizonte, Minas Gerais (Brazil); Santana, P., E-mail: iarapfcorrea@gmail.com [Universidade Federal de Minas Gerais, Departamento de Anatomia e Imagem, Av. Prof. Alfredo Balena 190, 30130-100 Belo Horizonte, Minas Gerais (Brazil)

    2016-10-15

    Computed tomography (CT) was introduced to medical practice in 1972. It generates images recognized by high diagnostic potential. CT allows investigation of structures in the human body inaccessible by conventional image methods, replacing invasive methods in many cases. Noise is a kind of variation of brightness observed on CT images, and it is inherent to this method. The magnitude of the noise is determined by the standard deviation of CT numbers of a region of interest in a homogeneous material. The aim of this study is to analyze the noise in head CT images generated by different acquisition protocols using four voltage values. Five different scans were performed using a female Alderson phantom and their images were analyzed with the RadiAnt software. With the average HU values and standard deviation of each scan, the values of noise were calculated in some region of interest. The obtained noise values were compared and it was observed that the 140 kV voltage promotes the in the lower noise in the image, resulting in better image quality. The results also show that the parameters, such as voltage and current, can be adjusted so that the noise can be decreased. Thus, acquisition protocols may be adapted to produce images with diagnostic quality and lower doses in patient. (Author)

  2. Patient doses and image quality in chest radiography: The influence of different beam qualities

    Directory of Open Access Journals (Sweden)

    Ciraj-Bjelac Olivera

    2007-01-01

    Full Text Available A simple method of assessing optimal X-ray beam quality in respect to patient exposure and image quality in chest screen-film radiography is presented here. Different beam qualities were generated by the use of various combinations of tube voltages (70 kV to 110 kV and Al and Cu filter thick nesses. Patient doses were assessed by kerma-area product measurements. Simultaneously, image quality was evaluated by a twofold method: a clinical study applying European quality criteria for the radiographic technique of image on image of 126 patients and a multifunctional home-made dosimetric phantom with embedded test objects. The quantification of image quality criteria yields a simpler method of optimizing image quality and patient dose relationships. Modifications of radiographic practice, based on image quality assessment and dose measurements, resulted in significant dose reductions and preservation of image quality. Through the use of harder beam quality, dose reduction of up to a value of factor 3 were observed, compared to the doses from previously used radiographic techniques, implying that sufficient image quality does not necessarily imply higher doses. As a result of the optimization process, an optimal radiographic technique was suggested.

  3. Body Image Ideal among Males and Females: Sociocultural Influences and Focus on Different Body Parts.

    Science.gov (United States)

    Stanford, Jacqueline N; McCabe, Marita P

    2002-11-01

    Past research has obtained mixed findings in relation to gender differences and other factors that shape ideal body image. The current study was designed to investigate these differences further, using a digital body image program to assess body image individually. As expected, females desired a body that was smaller than their current size, whereas males were split between wanting a smaller and larger body. The perceived messages from peers and parents were consistent with the individual's ideal image. Gender differences were also found with ratings of attractiveness and effectiveness. Females rated messages from peers and parents as more important than did males. For both males and females, opposite sex peers were the most important influences, and parents the least important.

  4. Image and Imaging an Emergency Department: Expense and Benefit of Different Quality Assessment Methods

    Directory of Open Access Journals (Sweden)

    Carmen Andrea Pfortmueller

    2013-01-01

    Full Text Available Introduction. In this era of high-tech medicine, it is becoming increasingly important to assess patient satisfaction. There are several methods to do so, but these differ greatly in terms of cost, time, and labour and external validity. The aim of this study is to describe and compare the structure and implementation of different methods to assess the satisfaction of patients in an emergency department. Methods. The structure and implementation of the different methods to assess patient satisfaction were evaluated on the basis of a 90-minute standardised interview. Results. We identified a total of six different methods in six different hospitals. The average number of patients assessed was 5012, with a range from 230 (M5 to 20 000 patients (M2. In four methods (M1, M3, M5, and M6, the questionnaire was composed by a specialised external institute. In two methods, the questionnaire was created by the hospital itself (M2, M4.The median response rate was 58.4% (range 9–97.8%. With a reminder, the response rate increased by 60% (M3. Conclusion. The ideal method to assess patient satisfaction in the emergency department setting is to use a patient-based, in-emergency department-based assessment of patient satisfaction, planned and guided by expert personnel.

  5. AN IMPROVED VARIATIONAL METHOD FOR HYPERSPECTRAL IMAGE PANSHARPENING WITH THE CONSTRAINT OF SPECTRAL DIFFERENCE MINIMIZATION

    Directory of Open Access Journals (Sweden)

    Z. Huang

    2017-09-01

    Full Text Available Variational pansharpening can enhance the spatial resolution of a hyperspectral (HS image using a high-resolution panchromatic (PAN image. However, this technology may lead to spectral distortion that obviously affect the accuracy of data analysis. In this article, we propose an improved variational method for HS image pansharpening with the constraint of spectral difference minimization. We extend the energy function of the classic variational pansharpening method by adding a new spectral fidelity term. This fidelity term is designed following the definition of spectral angle mapper, which means that for every pixel, the spectral difference value of any two bands in the HS image is in equal proportion to that of the two corresponding bands in the pansharpened image. Gradient descent method is adopted to find the optimal solution of the modified energy function, and the pansharpened image can be reconstructed. Experimental results demonstrate that the constraint of spectral difference minimization is able to preserve the original spectral information well in HS images, and reduce the spectral distortion effectively. Compared to original variational method, our method performs better in both visual and quantitative evaluation, and achieves a good trade-off between spatial and spectral information.

  6. An Improved Variational Method for Hyperspectral Image Pansharpening with the Constraint of Spectral Difference Minimization

    Science.gov (United States)

    Huang, Z.; Chen, Q.; Shen, Y.; Chen, Q.; Liu, X.

    2017-09-01

    Variational pansharpening can enhance the spatial resolution of a hyperspectral (HS) image using a high-resolution panchromatic (PAN) image. However, this technology may lead to spectral distortion that obviously affect the accuracy of data analysis. In this article, we propose an improved variational method for HS image pansharpening with the constraint of spectral difference minimization. We extend the energy function of the classic variational pansharpening method by adding a new spectral fidelity term. This fidelity term is designed following the definition of spectral angle mapper, which means that for every pixel, the spectral difference value of any two bands in the HS image is in equal proportion to that of the two corresponding bands in the pansharpened image. Gradient descent method is adopted to find the optimal solution of the modified energy function, and the pansharpened image can be reconstructed. Experimental results demonstrate that the constraint of spectral difference minimization is able to preserve the original spectral information well in HS images, and reduce the spectral distortion effectively. Compared to original variational method, our method performs better in both visual and quantitative evaluation, and achieves a good trade-off between spatial and spectral information.

  7. Color filter array pattern identification using variance of color difference image

    Science.gov (United States)

    Shin, Hyun Jun; Jeon, Jong Ju; Eom, Il Kyu

    2017-07-01

    A color filter array is placed on the image sensor of a digital camera to acquire color images. Each pixel uses only one color, since the image sensor can measure only one color per pixel. Therefore, empty pixels are filled using an interpolation process called demosaicing. The original and the interpolated pixels have different statistical characteristics. If the image is modified by manipulation or forgery, the color filter array pattern is altered. This pattern change can be a clue for image forgery detection. However, most forgery detection algorithms have the disadvantage of assuming the color filter array pattern. We present an identification method of the color filter array pattern. Initially, the local mean is eliminated to remove the background effect. Subsequently, the color difference block is constructed to emphasize the difference between the original pixel and the interpolated pixel. The variance measure of the color difference image is proposed as a means of estimating the color filter array configuration. The experimental results show that the proposed method is effective in identifying the color filter array pattern. Compared with conventional methods, our method provides superior performance.

  8. Sharpness enhancement of stereo images using binocular just-noticeable difference.

    Science.gov (United States)

    Jung, Seung-Won; Jeong, Jae-Yun; Ko, Sung-Jea

    2012-03-01

    In this paper, we propose a new sharpness enhancement algorithm for stereo images. Although the stereo image and its applications are becoming increasingly prevalent, there has been very limited research on specialized image enhancement solutions for stereo images. Recently, a binocular just-noticeable-difference (BJND) model that describes the sensitivity of the human visual system to luminance changes in stereo images has been presented. We introduce a novel application of the BJND model for the sharpness enhancement of stereo images. To this end, an overenhancement problem in the sharpness enhancement of stereo images is newly addressed, and an efficient solution for reducing the overenhancement is proposed. The solution is found within an optimization framework with additional constraint terms to suppress the unnecessary increase in luminance values. In addition, the reliability of the BJND model is taken into account by estimating the accuracy of stereo matching. Experimental results demonstrate that the proposed algorithm can provide sharpness-enhanced stereo images without producing excessive distortion.

  9. Gender and racial/ethnic differences in body image development among college students.

    Science.gov (United States)

    Gillen, Meghan M; Lefkowitz, Eva S

    2012-01-01

    In the present study we used longitudinal methods to examine body image development during the early part of college. Students (N=390; 54% female) who identified as African American (32%), Latino/a American (27%), and European American (41%) completed surveys during their first, second, and third semesters at college. There were overall gender and racial/ethnic differences in all three aspects of body image, and both stability and change in body image development. Female students' appearance evaluation became more positive, whereas male students' appearance evaluation showed no significant change. Individuals' body areas satisfaction increased over time, but remained stable when controlling for BMI. Appearance orientation did not change, and there were no racial/ethnic differences in body image development. Experiences in the college environment may play a role in these trends. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Change Detection with GRASS GIS – Comparison of images taken by different sensors

    Directory of Open Access Journals (Sweden)

    Michael Fuchs

    2009-04-01

    Full Text Available Images of American military reconnaissance satellites of the Sixties (CORONA in combination with modern sensors (SPOT, QuickBird were used for detection of changes in land use. The pilot area was located about 40 km northwest of Yemen’s capital Sana’a and covered approximately 100 km2 . To produce comparable layers from images of distinctly different sources, the moving window technique was applied, using the diversity parameter. The resulting difference layers reveal plausible and interpretable change patterns, particularly in areas where urban sprawl occurs.The comparison of CORONA images with images taken by modern sensors proved to be an additional tool to visualize and quantify major changes in land use. The results should serve as additional basic data eg. in regional planning.The computation sequence was executed in GRASS GIS.

  11. Mapping the different methods adopted for diagnostic imaging instruction at medical schools in Brazil.

    Science.gov (United States)

    Chojniak, Rubens; Carneiro, Dominique Piacenti; Moterani, Gustavo Simonetto Peres; Duarte, Ivone da Silva; Bitencourt, Almir Galvão Vieira; Muglia, Valdair Francisco; D'Ippolito, Giuseppe

    2017-01-01

    To map the different methods for diagnostic imaging instruction at medical schools in Brazil. In this cross-sectional study, a questionnaire was sent to each of the coordinators of 178 Brazilian medical schools. The following characteristics were assessed: teaching model; total course hours; infrastructure; numbers of students and professionals involved; themes addressed; diagnostic imaging modalities covered; and education policies related to diagnostic imaging. Of the 178 questionnaires sent, 45 (25.3%) were completed and returned. Of those 45 responses, 17 (37.8%) were from public medical schools, whereas 28 (62.2%) were from private medical schools. Among the 45 medical schools evaluated, the method of diagnostic imaging instruction was modular at 21 (46.7%), classic (independent discipline) at 13 (28.9%), hybrid (classical and modular) at 9 (20.0%), and none of the preceding at 3 (6.7%). Diagnostic imaging is part of the formal curriculum at 36 (80.0%) of the schools, an elective course at 3 (6.7%), and included within another modality at 6 (13.3%). Professors involved in diagnostic imaging teaching are radiologists at 43 (95.5%) of the institutions. The survey showed that medical courses in Brazil tend to offer diagnostic imaging instruction in courses that include other content and at different time points during the course. Radiologists are extensively involved in undergraduate medical education, regardless of the teaching methodology employed at the institution.

  12. Mapping the different methods adopted for diagnostic imaging instruction at medical schools in Brazil

    Science.gov (United States)

    Chojniak, Rubens; Carneiro, Dominique Piacenti; Moterani, Gustavo Simonetto Peres; Duarte, Ivone da Silva; Bitencourt, Almir Galvão Vieira; Muglia, Valdair Francisco; D'Ippolito, Giuseppe

    2017-01-01

    Objective To map the different methods for diagnostic imaging instruction at medical schools in Brazil. Materials and Methods In this cross-sectional study, a questionnaire was sent to each of the coordinators of 178 Brazilian medical schools. The following characteristics were assessed: teaching model; total course hours; infrastructure; numbers of students and professionals involved; themes addressed; diagnostic imaging modalities covered; and education policies related to diagnostic imaging. Results Of the 178 questionnaires sent, 45 (25.3%) were completed and returned. Of those 45 responses, 17 (37.8%) were from public medical schools, whereas 28 (62.2%) were from private medical schools. Among the 45 medical schools evaluated, the method of diagnostic imaging instruction was modular at 21 (46.7%), classic (independent discipline) at 13 (28.9%), hybrid (classical and modular) at 9 (20.0%), and none of the preceding at 3 (6.7%). Diagnostic imaging is part of the formal curriculum at 36 (80.0%) of the schools, an elective course at 3 (6.7%), and included within another modality at 6 (13.3%). Professors involved in diagnostic imaging teaching are radiologists at 43 (95.5%) of the institutions. Conclusion The survey showed that medical courses in Brazil tend to offer diagnostic imaging instruction in courses that include other content and at different time points during the course. Radiologists are extensively involved in undergraduate medical education, regardless of the teaching methodology employed at the institution. PMID:28298730

  13. Review: magnetic resonance imaging of male/female differences in human adolescent brain anatomy

    OpenAIRE

    Giedd Jay N; Raznahan Armin; Mills Kathryn L; Lenroot Rhoshel K

    2012-01-01

    Abstract Improvements in neuroimaging technologies, and greater access to their use, have generated a plethora of data regarding male/female differences in the developing brain. Examination of these differences may shed light on the pathophysiology of the many illnesses that differ between the sexes and ultimately lead to more effective interventions. In this review, we attempt to synthesize the anatomic magnetic resonance imaging (MRI) literature of male/female brain differences with emphasi...

  14. Multiresolution approach to processing images for different applications interaction of lower processing with higher vision

    CERN Document Server

    Vujović, Igor

    2015-01-01

    This book presents theoretical and practical aspects of the interaction between low and high level image processing. Multiresolution analysis owes its popularity mostly to wavelets and is widely used in a variety of applications. Low level image processing is important for the performance of many high level applications. The book includes examples from different research fields, i.e. video surveillance; biomedical applications (EMG and X-ray); improved communication, namely teleoperation, telemedicine, animation, augmented/virtual reality and robot vision; monitoring of the condition of ship systems and image quality control.

  15. Individual thorax geometry reduces position and size differences in reconstructed images of electrical impedance tomography.

    Science.gov (United States)

    Zhao, Zhanqi; Frerichs, Inéz; Pulletz, Sven; Müller-Lisse, Ullrich; Möller, Knut

    2014-01-01

    Due to the ill-posed problem, the electrical impedance within the thorax cannot be exactly reconstructed. The aim of our study was to prove that reconstruction with individual thorax geometry improved the quality of EIT (electrical impedance tomography) images. Seven mechanically ventilated patients with acute respiratory distress syndrome were examined by EIT. The thorax contours were determined from routine computed tomography (CT) images based on automatic threshold filtering. EIT raw data was reconstructed offline with (1) back-projection with circular forward model; (2) GREIT reconstruction method with circular forward model and (3) GREIT with individual thorax geometry. The resulting EIT images were compared to rescaled CT images. The distance between the lung contour and the thorax contour was calculated for each method and the differences to that in CT were denoted as position differences. Shape differences was defined as the ratio of thorax (or lungs) size in EIT and that in rescaled CT. Method (3) has the smallest position differences (6.6 ± 2.8, 5.3 ± 3.3, 2.3 ± 1.4 in pixel, for each reconstruction method respectively; mean ± SD). The thorax and lungs sizes in the transformed CT images were 514 ± 73 and 177 ± 39. Shape differences of thorax were 1.81 ± 0.26, 1.81 ± 0.26, 1.10 ± 0.12 and that of lungs were 1.69 ± 0.45, 1.52 ± 0.45, 1.34 ± 0.35 for each method respectively. The reconstructed images using the GREIT method with individual thorax geometry were more realistic. Improvement of EIT image quality may foster the acceptance of EIT in routine clinical use.

  16. Image quality assessment and medical physics evaluation of different portable dental X-ray units.

    Science.gov (United States)

    Pittayapat, Pisha; Oliveira-Santos, Christiano; Thevissen, Patrick; Michielsen, Koen; Bergans, Niki; Willems, Guy; Debruyckere, Deborah; Jacobs, Reinhilde

    2010-09-10

    Recently developed portable dental X-ray units increase the mobility of the forensic odontologists and allow more efficient X-ray work in a disaster field, especially when used in combination with digital sensors. This type of machines might also have potential for application in remote areas, military and humanitarian missions, dental care of patients with mobility limitation, as well as imaging in operating rooms. To evaluate radiographic image quality acquired by three portable X-ray devices in combination with four image receptors and to evaluate their medical physics parameters. Images of five samples consisting of four teeth and one formalin-fixed mandible were acquired by one conventional wall-mounted X-ray unit, MinRay 60/70 kVp, used as a clinical standard, and three portable dental X-ray devices: AnyRay 60 kVp, Nomad 60 kVp and Rextar 70 kVp, in combination with a phosphor image plate (PSP), a CCD, or a CMOS sensor. Three observers evaluated images for standard image quality besides forensic diagnostic quality on a 4-point rating scale. Furthermore, all machines underwent tests for occupational as well as patient dosimetry. Statistical analysis showed good quality imaging for all system, with the combination of Nomad and PSP yielding the best score. A significant difference in image quality between the combination of the four X-ray devices and four sensors was established (p1m: Rextar <0.2 microGy, MinRay <0.1 microGy). The present study demonstrated the feasibility of three portable X-ray systems to be used for specific indications, based on acceptable image quality and sufficient accuracy of the machines and following the standard guidelines for radiation hygiene. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  17. Improvement of Closed Crack Selectivity in Nonlinear Ultrasonic Imaging Using Fundamental Wave Amplitude Difference

    Science.gov (United States)

    Ikeuchi, Masako; Jinno, Kentaro; Ohara, Yoshikazu; Yamanaka, Kazushi

    2013-07-01

    To realize the high selectivity of closed cracks, we propose a fundamental wave amplitude difference (FAD) method based on the threshold behavior of fundamental waves caused by the contact vibration of closed cracks. This is realized by the subtraction of a fundamental array (FA) image at a small input amplitude multiplied by the amplification factor from that at a large input amplitude. The formulation clarified that FAD can selectively image closed cracks while eliminating other linear scatterers, which cannot be completely eliminated by the subharmonic wave amplitude difference (SAD) method. Furthermore, FAD was experimentally verified in a closed fatigue crack specimen using the closed-crack-imaging method of subharmonic phased array for crack evaluation (SPACE). Thus, we demonstrated that FAD is useful for achieving the higher selectivity of closed cracks against other linear scatterers than previous amplitude difference methods without filtering out the subharmonic or superharmonic waves.

  18. MO-B-BRC-00: Prostate HDR Treatment Planning - Considering Different Imaging Modalities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-15

    Brachytherapy has proven to be an effective treatment option for prostate cancer. Initially, prostate brachytherapy was delivered through permanently implanted low dose rate (LDR) radioactive sources; however, high dose rate (HDR) temporary brachytherapy for prostate cancer is gaining popularity. Needle insertion during prostate brachytherapy is most commonly performed under ultrasound (U/S) guidance; however, treatment planning may be performed utilizing several imaging modalities either in an intra- or post-operative setting. During intra-operative prostate HDR, the needles are imaged during implantation, and planning may be performed in real time. At present, the most common imaging modality utilized for intra-operative prostate HDR is U/S. Alternatively, in the post-operative setting, following needle implantation, patients may be simulated with computed tomography (CT) or magnetic resonance imaging (MRI). Each imaging modality and workflow provides its share of benefits and limitations. Prostate HDR has been adopted in a number of cancer centers across the nation. In this educational session, we will explore the role of U/S, CT, and MRI in HDR prostate brachytherapy. Example workflows and operational details will be shared, and we will discuss how to establish a prostate HDR program in a clinical setting. Learning Objectives: Review prostate HDR techniques based on the imaging modality Discuss the challenges and pitfalls introduced by the three imagebased options for prostate HDR brachytherapy Review the QA process and learn about the development of clinical workflows for these imaging options at different institutions.

  19. Different technical possibilities of post-therapeutic tandem 90Y/ /177Lu-DOTATATE imaging.

    Science.gov (United States)

    Kunikowska, Jolanta; Bajera, Adam; Sawicka, Magdalena; Czwarnowski, Piotr; Pawłowicz, Bożena; Aksamit, Dariusz; Pawlak, Dariusz; Królicki, Leszek

    2013-01-01

    Neuroendocrine tumors (NETs) are a heterogeneous group of neoplasms derived from endocrine stem cells.These tumors are characterized by overexpression of somatostatin receptors (SSTR), which is utilized for imaging using SSTR analogs. Peptide receptor radionuclide therapy (PRRT) somatostatin analogs labeled with 90Y and 177Lu in neuroendocrine tumors (NETs) results in symptomatic improvement, prolonged survival,and enhanced quality of life. The post-therapeutic imaging leadsto possibility of biodistribution of therapy. The aim of our study was to describe different possibilities of post-therapeutic imaging in patients underwent tandem therapy 90Y/177Lu-DOTATATE with preliminary results of 90Y PET imaging. Thirty patients (11 men, 19 women; the mean age 55 ± 10.9 y) with histological confirmation of metastatic neuroendocrine tumors (G1 and G2) were treated with tandem therapy 90Y/177Lu-DOTATATE. WHBA scan and SPECT acquisition of the abdomen were performed 24 hours post therapy injection, on the dual-head Varicam camera (ELSCINT) using 177Lu photopeak and 90Y bremsstrahlung. PET imaging of 90Y component was done on Siemens Biograph Truepoint PET/CT (window 511 keV ± 15%)4 hours after 90Y/177Lu-DOTATATE. Additionally phantom studies were performer to analyze the spatial resolution of different protocols. Out of all the patients, median OS was 49.8 months and median EFS time 24.3 months. Spatial resolution achieved for 90Y, 177 Lu and PET imaging of 90Y component measured using the phantom of the torso filled up with water was 20 mm, 8 mm and 4-5 mm FWHM, respectively. Spatial resolution in human body in our study was about 30 mm for 90Y, 15 mm for 177Lu and 25-30 mm for PET imaging of 90Y component. The theoretically best spatial resolution offers PET scanner, however it is important to keep in mind that 90Y-imaging PET is not used for diagnosis purposes (small activities)but rather to present new possibility of post-therapeutic imaging (substantially higher

  20. These images show thermal infrared radiation from Jupiter at different wavelengths which are diagnos

    Science.gov (United States)

    2002-01-01

    These images show thermal infrared radiation from Jupiter at different wavelengths which are diagnostic of physical phenomena The 7.85-micron image in the upper left shows stratospheric temperatures which are elevated in the region of the A fragment impact (to the left of bottom). Temperatures deeper in the atmosphere near 150-mbar are shown by the 17.2-micron image in the upper right. There is a small elevation of temperatures at this depth, indicated by the arrow, and confirmed by other measurements near this wavelength. This indicates that the influence of the impact of fragment A on the troposphere has been minimal. The two images in the bottom row show no readily apparent perturbation of the ammmonia condensate cloud field near 600 mbar, as diagnosed by 8.57-micron radiation, and deeper cloud layers which are diagnosed by 5-micron radiation.

  1. Comparing Image Perception of Bladder Tumors in Four Different Storz Professional Image Enhancement System Modalities Using the íSPIES App.

    Science.gov (United States)

    Kamphuis, Guido M; de Bruin, D Martijn; Brandt, Martin J; Knoll, Thomas; Conort, Pierre; Lapini, Alberto; Dominguez-Escrig, Jose L; de la Rosette, Jean J M C H

    2016-05-01

    To evaluate the variation of interpretation of the same bladder urothelium image in different Storz Professional Image Enhancement System (SPIES) modalities. SPIES contains a White light (WL), Spectra A (SA), Spectra B (SB), and Clara and Chroma combined (CC) modality. An App for the iPAD retina was developed to study evaluation of images. A total of 80 images from 20 bladder areas acquired in four modalities were included. Seventy-three participants completed the study. Images were analyzed on differences in delineated tumor margin variation, perceived quality of the image, and delineation time. A separation between high agreement (n = 14) and low agreement (n = 6) images was found. In high agreement images, no difference in root mean square (RMS) was found between modalities. In low agreement images, WL (26.5 pixels) and SA (33.4 pixels) had a higher RMS than CC (18 pixels) and SB (21.4 pixels). The quality of SPIES modalities images was rated significantly higher. Delineation time was similar. In low agreement cases, images in CC and SB have less variation in interpretation than WL and SA. The image quality in SPIES modalities is graded significantly higher than WL. There is no difference in delineation time between modalities.

  2. Heterogeneity of paclitaxel distribution in different tumor models assessed by MALDI mass spectrometry imaging.

    Science.gov (United States)

    Giordano, Silvia; Zucchetti, Massimo; Decio, Alessandra; Cesca, Marta; Fuso Nerini, Ilaria; Maiezza, Marika; Ferrari, Mariella; Licandro, Simonetta Andrea; Frapolli, Roberta; Giavazzi, Raffaella; Maurizio, D'Incalci; Davoli, Enrico; Morosi, Lavinia

    2016-12-21

    The penetration of anticancer drugs in solid tumors is important to ensure the therapeutic effect, so methods are needed to understand drug distribution in different parts of the tumor. Mass spectrometry imaging (MSI) has great potential in this field to visualize drug distribution in organs and tumor tissues with good spatial resolution and superior specificity. We present an accurate and reproducible imaging method to investigate the variation of drug distribution in different parts of solid tumors. The method was applied to study the distribution of paclitaxel in three ovarian cancer models with different histopathological characteristics and in colon cancer (HCT116), breast cancer (MDA-MB-231) and malignant pleural mesothelioma (MPM487). The heterogeneous drug penetration in the tumors is evident from the MALDI imaging results and from the images analysis. The differences between the various models do not always relate to significant changes in drug content in tumor homogenate examined by classical HPLC analysis. The specificity of the method clarifies the heterogeneity of the drug distribution that is analyzed from a quantitative point of view too, highlighting how marked are the variations of paclitaxel amounts in different part of solid tumors.

  3. Ethnic differences in the effects of media on body image: the effects of priming with ethnically different or similar models.

    Science.gov (United States)

    Bruns, Gina L; Carter, Michele M

    2015-04-01

    Media exposure has been positively correlated with body dissatisfaction. While body image concerns are common, being African American has been found to be a protective factor in the development of body dissatisfaction. Participants either viewed ten advertisements showing 1) ethnically-similar thin models; 2) ethnically-different thin models; 3) ethnically-similar plus-sized models; and 4) ethnically-diverse plus-sized models. Following exposure, body image was measured. African American women had less body dissatisfaction than Caucasian women. Ethnically-similar thin-model conditions did not elicit greater body dissatisfaction scores than ethnically-different thin or plus-sized models nor did the ethnicity of the model impact ratings of body dissatisfaction for women of either race. There were no differences among the African American women exposed to plus-sized versus thin models. Among Caucasian women exposure to plus-sized models resulted in greater body dissatisfaction than exposure to thin models. Results support existing literature that African American women experience less body dissatisfaction than Caucasian women even following exposure to an ethnically-similar thin model. Additionally, women exposed to plus-sized model conditions experienced greater body dissatisfaction than those shown thin models. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Cross-cultural studies of sex differences in normal adolescents' self-image.

    Science.gov (United States)

    Ostrov, E; Offer, D; Howard, K I

    1986-01-01

    One context for understanding an adolescent's (or any other individual's) abnormal functioning is an appreciation of normal or modal functioning in the culture to which that adolescent belongs. After decades of research and clinical observation there is no consensus about what constitutes modal adolescent functioning in the United States. Much less is known about adolescent functioning in other cultures. Results were suggestive of large, cross-cultural differences in self-image among normal adolescents. In most areas American teenagers reported the best functioning while Bengali teenagers reported the worst. There were consistent gender differences in self-image across cultures, with adolescent girls showing poorer self-image than adolescent boys in many areas. Results are discussed from the point of view of difficulties in doing cross-cultural psychiatric research and the need for further research in this field.

  5. Variability of textural features in FDG PET images due to different acquisition modes and reconstruction parameters

    DEFF Research Database (Denmark)

    Galavis, P.E.; Hollensen, Christian; Jallow, N.

    2010-01-01

    Background. Characterization of textural features (spatial distributions of image intensity levels) has been considered as a tool for automatic tumor segmentation. The purpose of this work is to study the variability of the textural features in PET images due to different acquisition modes...... reconstruction parameters. Lesions were segmented on a default image using the threshold of 40% of maximum SUV. Fifty different texture features were calculated inside the tumors. The range of variations of the features were calculated with respect to the average value. Results. Fifty textural features were...... classified based on the range of variation in three categories: small, intermediate and large variability. Features with small variability (range 30%). Conclusion. Textural features such as entropy-first order, energy, maximal correlation coefficient, and low-gray level run emphasis exhibited small...

  6. Different imaging characteristics of concurrent pituitary adenomas in a patient with Cushing's disease.

    Science.gov (United States)

    Mehta, Gautam U; Montgomery, Blake K; Raghavan, Pooja; Sharma, Susmeeta; Nieman, Lynnette K; Patronas, Nicholas; Oldfield, Edward H; Chittiboina, Prashant

    2015-05-01

    We report a patient with Cushing's disease (CD) and two pituitary adenomas that demonstrated different imaging characteristics and therefore suggest an alternative imaging strategy for these patients. A 42-year-old woman presented with signs and symptoms of CD. Biochemical evaluation confirmed hypercortisolemia and suggested CD. On pituitary MRI with spoiled gradient recalled acquisition in the steady-state and T1-weighted spin echo protocols, a 5mm hypoenhancing region typical for a pituitary adenoma was identified on the left. However, after surgical resection the patient remained hypercortisolemic and pathology revealed a non-functional adenoma. At early repeat surgical exploration a 10mm adenoma was found in the right side of the gland. Postoperatively the patient became hypocortisolemic and pathology demonstrated an adrenocorticotropic hormone (ACTH)-staining adenoma. On review of the initial MRI this tumor corresponded to a region of contrast retention best visualized on delayed fluid attenuated inversion recovery (FLAIR) imaging. While the incidentaloma in this case demonstrated classical imaging characteristics of a pituitary adenoma the larger ACTH-secreting tumor was best appreciated by contrast retention. This suggests a role for delayed postcontrast FLAIR imaging in the preoperative evaluation of CD. ACTH-secreting tumors causing CD cause significant morbidity. Due to their small size, a pituitary adenoma is frequently not identified on imaging despite endocrinologic testing suggesting CD. Regardless of improvements in MRI, many tumors are only identified at surgical exploration. Published by Elsevier Ltd.

  7. Gender Differences in Adolescent Sport Participation, Teasing, Self-Objectification and Body Image Concerns

    Science.gov (United States)

    Slater, Amy; Tiggemann, Marika

    2011-01-01

    This study examined gender differences in adolescent participation in sport and physical activity, in teasing experiences specific to the physical activity domain, and the relationship between adolescent physical activity and body image. A sample of 714 adolescents (332 girls, 382 boys) aged between 12 and 16 years completed measures of…

  8. Computed Tomography Radiation Dose Reduction: Effect of Different Iterative Reconstruction Algorithms on Image Quality

    NARCIS (Netherlands)

    Willemink, M.J.; Takx, R.A.P.; Jong, P.A. de; Budde, R.P.; Bleys, R.L.; Das, M.; Wildberger, J.E.; Prokop, M.; Buls, N.; Mey, J. de; Leiner, T.; Schilham, A.M.

    2014-01-01

    We evaluated the effects of hybrid and model-based iterative reconstruction (IR) algorithms from different vendors at multiple radiation dose levels on image quality of chest phantom scans.A chest phantom was scanned on state-of-the-art computed tomography scanners from 4 vendors at 4 dose levels

  9. Body image and self-esteem: a study of gender differences among ...

    African Journals Online (AJOL)

    This study looked at the conceptualisation of body image and its relationship with self-esteem and investigated for gender differences in these two aspects of the self. Two hundred and forty three randomly selected adolescents responded to a structured self-report schedule. Varimax rotated principal component analysis ...

  10. Evaluation of Different Irrigation Methods for an Apple Orchard Using an Aerial Imaging System

    Directory of Open Access Journals (Sweden)

    Duke M. Bulanon

    2016-06-01

    Full Text Available Regular monitoring and assessment of crops is one of the keys to optimal crop production. This research presents the development of a monitoring system called the Crop Monitoring and Assessment Platform (C-MAP. The C-MAP is composed of an image acquisition unit which is an off-the-shelf unmanned aerial vehicle (UAV equipped with a multispectral camera (near-infrared, green, blue, and an image processing and analysis component. The experimental apple orchard at the Parma Research and Extension Center of the University of Idaho was used as the target for monitoring and evaluation. Five experimental rows of the orchard were randomly treated with five different irrigation methods. An image processing algorithm to detect individual trees was developed to facilitate the analysis of the rows and it was able to detect over 90% of the trees. The image analysis of the experimental rows was based on vegetation indices and results showed that there was a significant difference in the Enhanced Normalized Difference Vegetation Index (ENDVI among the five different irrigation methods. This demonstrates that the C-MAP has very good potential as a monitoring tool for orchard management.

  11. Image enhancement methods for turbulence mitigation and the influence of different color spaces

    Science.gov (United States)

    Huebner, Claudia S.

    2015-10-01

    In mid- to long-range horizontal imaging applications it is quite often atmospheric turbulence which limits the performance of an electro-optical system rather than the design and quality of the system itself. Even weak or moderate turbulence conditions can suffice to cause significant image degradation, the predominant effects being image dancing and blurring. To mitigate these effects many different methods have been proposed, most of which use either a hardware approach, such as adaptive optics, or a software approach. A great number of these methods are highly specialized with regard to input data, e.g. aiming exclusively at very short exposure images or at infrared data. So far, only a very limited number of these methods are concerned specifically with the restoration of RGB colour video. Beside motion compensation and deblurring, contrast enhancement plays a vital part in many turbulence mitigation schemes. While most contrast enhancement techniques, such as Contrast Limited Adaptive Histogram Equalization (CLAHE) work quite well on monochrome data or single colour frames, they tend to amplify noise in a colour video stream disproportionately, especially in scenes with low contrast. Therefore, in this paper the impact of different colour spaces (RGB, LAB, HSV) on the application of such typical image enhancement techniques is discussed and evaluated with regard to suppressing temporal noise as well as to their suitability for use in software-based turbulence mitigation algorithms.

  12. Electric imaging through evolution, a modeling study of commonalities and differences.

    Science.gov (United States)

    Pedraja, Federico; Aguilera, Pedro; Caputi, Angel A; Budelli, Ruben

    2014-07-01

    Modeling the electric field and images in electric fish contributes to a better understanding of the pre-receptor conditioning of electric images. Although the boundary element method has been very successful for calculating images and fields, complex electric organ discharges pose a challenge for active electroreception modeling. We have previously developed a direct method for calculating electric images which takes into account the structure and physiology of the electric organ as well as the geometry and resistivity of fish tissues. The present article reports a general application of our simulator for studying electric images in electric fish with heterogeneous, extended electric organs. We studied three species of Gymnotiformes, including both wave-type (Apteronotus albifrons) and pulse-type (Gymnotus obscurus and Gymnotus coropinae) fish, with electric organs of different complexity. The results are compared with the African (Gnathonemus petersii) and American (Gymnotus omarorum) electric fish studied previously. We address the following issues: 1) how to calculate equivalent source distributions based on experimental measurements, 2) how the complexity of the electric organ discharge determines the features of the electric field and 3) how the basal field determines the characteristics of electric images. Our findings allow us to generalize the hypothesis (previously posed for G. omarorum) in which the perioral region and the rest of the body play different sensory roles. While the "electrosensory fovea" appears suitable for exploring objects in detail, the rest of the body is likened to a "peripheral retina" for detecting the presence and movement of surrounding objects. We discuss the commonalities and differences between species. Compared to African species, American electric fish show a weaker field. This feature, derived from the complexity of distributed electric organs, may endow Gymnotiformes with the ability to emit site-specific signals to be

  13. Monitoring of biofilm formation on different material surfaces of medical devices using hyperspectral imaging method

    Science.gov (United States)

    Kim, Do-Hyun; Kim, Moon S.; Hwang, Jeeseong

    2012-03-01

    Contamination of the inner surface of indwelling (implanted) medical devices by microbial biofilm is a serious problem. Some microbial bacteria such as Escherichia coli form biofilms that lead to potentially lifethreatening infections. Other types of medical devices such as bronchoscopes and duodenoscopes account for the highest number of reported endoscopic infections where microbial biofilm is one of the major causes for these infections. We applied a hyperspectral imaging method to detect biofilm contamination on the surface of several common materials used for medical devices. Such materials include stainless steel, titanium, and stainless-steeltitanium alloy. Potential uses of hyperspectral imaging technique to monitor biofilm attachment to different material surfaces are discussed.

  14. Application of local binary pattern and human visual Fibonacci texture features for classification different medical images

    Science.gov (United States)

    Sanghavi, Foram; Agaian, Sos

    2017-05-01

    The goal of this paper is to (a) test the nuclei based Computer Aided Cancer Detection system using Human Visual based system on the histopathology images and (b) Compare the results of the proposed system with the Local Binary Pattern and modified Fibonacci -p pattern systems. The system performance is evaluated using different parameters such as accuracy, specificity, sensitivity, positive predictive value, and negative predictive value on 251 prostate histopathology images. The accuracy of 96.69% was observed for cancer detection using the proposed human visual based system compared to 87.42% and 94.70% observed for Local Binary patterns and the modified Fibonacci p patterns.

  15. Ultrasound Imaging of Mammary Glands in Dairy Heifers at Different Stages of Growth

    OpenAIRE

    Nishimura, Maki; Yoshida, Tetsuya; El-KHODERY, Sabry; MIYOSHI, Masafumi; FURUOKA, Hidefumi; YASUDA, Jun; MIYAHARA, Kazuro; 古岡, 秀文; 宮原, 和郎

    2011-01-01

    To obtain B-mode ultrasound images of mammary glands in dairy heifers at different stages of growth, 25 clinically normal Holstein heifers were used. The heifers were divided into 5 groups (n=5/group) by stage of their growth: 2-month-old (group 1), 5-month-old (group 2), postpuberty (group 3), mid (group 4), and late (group 5) pregnancy. Furthermore, the sections of mammary glands were observed grossly at postmortem examination in one heifer in each group. Ultrasound images varied with the d...

  16. Detection accuracy of proximal caries by phosphor plate and cone-beam computerized tomography images scanned with different resolutions.

    Science.gov (United States)

    Cheng, Jun-Ge; Zhang, Zhi-Ling; Wang, Xiao-Yan; Zhang, Zu-Yan; Ma, Xu-Chen; Li, Gang

    2012-08-01

    This study was carried out to assess whether the spatial resolution has an impact on the detection accuracy of proximal caries in flat panel CBCT (cone beam computerized tomography) images and if the detection accuracy can be improved by flat panel CBCT images scanned with high spatial resolution when compared to digital intraoral images. The CBCT test images of 45 non-restored human permanent teeth were respectively scanned with the ProMax 3D and the DCT Pro scanners at different resolutions. Digital images were obtained with a phosphor plate imaging system Digora Optime. Eight observers evaluated all the test images for carious lesion within the 90 proximal surfaces. With the histological examination serving as the reference standard, observer performances were evaluated by receiver operating characteristic (ROC) curves. The areas under the ROC curves were analyzed with two-way analysis of variance. No significant differences were found among the CBCT images and between CBCT and digital images when only proximal enamel caries was detected (p = 0.989). With respect to the detection of proximal dentinal caries, significant difference was found between CBCT and digital images (p proximal caries in flat panel CBCT images. The flat panel CBCT images scanned with high spatial resolution did not improve the detection accuracy of proximal enamel caries compared to digital intraoral images. CBCT images scanned with high spatial resolutions could not be used for proximal caries detection.

  17. Technical and radiological image quality comparison of different liquid crystal displays for radiology

    Directory of Open Access Journals (Sweden)

    Dams FE

    2014-10-01

    Full Text Available Francina EM Dams,2 KY Esther Leung,1 Pieter HM van der Valk,2 Marc CJM Kock,2 Jeroen Bosman,1 Sjoerd P Niehof1 1Medical Physics and Technology, 2Department of Radiology, Albert Schweitzer Hospital, Dordrecht, The Netherlands Background: To inform cost-effective decisions in purchasing new medical liquid crystal displays, we compared the image quality in displays made by three manufacturers. Methods: We recruited 19 radiologists and residents to compare the image quality of four liquid crystal displays, including 3-megapixel Barco®, Eizo®, and NEC® displays and a 6-megapixel Barco display. The evaluators were blinded to the manufacturers' names. Technical assessments were based on acceptance criteria and test patterns proposed by the American Association of Physicists in Medicine. Radiological assessments were performed on images from the American Association of Physicists in Medicine Task Group 18. They included X-ray images of the thorax, knee, and breast, a computed tomographic image of the thorax, and a magnetic resonance image of the brain. Image quality was scored on an analog scale (range 0–10. Statistical analysis was performed with repeated-measures analysis of variance. Results: The Barco 3-megapixel display passed all acceptance criteria. The Eizo and NEC displays passed the acceptance criteria, except for the darkest pixel value in the grayscale display function. The Barco 6-megapixel display failed criteria for the maximum luminance response and the veiling glare. Mean radiological assessment scores were 7.8±1.1 (Barco 3-megapixel, 7.8±1.2 (Eizo, 8.1±1.0 (NEC, and 8.1±1.0 (Barco 6-megapixel. No significant differences were found between displays. Conclusion: According to the tested criteria, all the displays had comparable image quality; however, there was a three-fold difference in price between the most and least expensive displays. Keywords: data display, humans, radiographic image enhancement, user-computer interface

  18. Different methods of image segmentation in the process of meat marbling evaluation

    Science.gov (United States)

    Ludwiczak, A.; Ślósarz, P.; Lisiak, D.; Przybylak, A.; Boniecki, P.; Stanisz, M.; Koszela, K.; Zaborowicz, M.; Przybył, K.; Wojcieszak, D.; Janczak, D.; Bykowska, M.

    2015-07-01

    The level of marbling in meat assessment based on digital images is very popular, as computer vision tools are becoming more and more advanced. However considering muscle cross sections as the data source for marbling level evaluation, there are still a few problems to cope with. There is a need for an accurate method which would facilitate this evaluation procedure and increase its accuracy. The presented research was conducted in order to compare the effect of different image segmentation tools considering their usefulness in meat marbling evaluation on the muscle anatomical cross - sections. However this study is considered to be an initial trial in the presented field of research and an introduction to ultrasonic images processing and analysis.

  19. MR temperature imaging using PRF phase difference and a geometric model-based fat suppression method.

    Science.gov (United States)

    Liu, Shoubin; Zhou, Yanming

    2015-01-01

    Because protons in fat do not exhibit a temperature-dependent frequency shift, proton resonance frequency shift (PRFS)-based MR thermometry always suffers from disturbances due to the presence of fats or lipids. A new fat suppression method for PRFS-based MR thermometry is proposed to obtain accurate variation of phase angle. Similar to the approach of separating fat and water with the two-point Dixon technique, we first scan a complex MR image for reference and then scan another complex image varying with temperature at the same TE point. Based on the conventional PRFS method, we use geometric relationships to remove the effect of fat on the variation of the phase angle. Two phantoms with different water-to-fat ratios are involved in the temperature mapping test. Experimental results show that the temperature images of two phantoms are approximated under the same conditions. The proposed fat suppression method is simple and effective for PRFS-based MR thermometry.

  20. Toward image registration process: Using different interpolation methods in case of subpixel displacement

    Science.gov (United States)

    Flores Padilla, Deyanira; Jimenez-Hernández, Hugo; Reynosa Canseco, Jaqueline

    2016-09-01

    Interpolating for data sample is required in many image processing methods. For example, in the estimation of displacement which are smaller than one pixel. In the case of displacement calculation in an image sequence using the numerical method, Newton-Rapson is very common to use a linear interpolator due to its simplicity and speed. However this method generates discontinuous functions. Therefore, theoretically it should not be used in combination with Newton-Rapson due to the use of the derivative in the numerical method. This work shows a comparative analysis of different interpolators, along with a comparison between "real world" and image displacements and their relationship. All of this with the purpose of identifying which interpolator offers the most exact approximation in the estimation of displacement calculation.

  1. How to Find More Supernovae with Less Work: Object Classification Techniques for Difference Imaging

    Science.gov (United States)

    Bailey, Stephen J.; Aldering, G.; Aragon, C.; Bongard, S.; Childress, M.; Loken, S.; Nugent, P.; Perlmutter, S.; Runge, K.; Scalzo, R.; Romano, R.; Thomas, R.; Weaver, B.; Baltay, C.; Bauer, A.; Herrera, D.; Rabinowitz, D.; Pecontal, E.; Rigaudier, G.; Antilogus, P.; Gilles, S.; Pain, R.; Pereira, R.; Buton, C.; Copin, Y.

    2006-12-01

    We present the results of applying new object classification techniques to difference images in the context of the SNfactory supernova search. Most current supernova searches subtract reference images from new images, identify leftover objects, and apply simple threshold cuts on parameters such as statistical significance, shape, and motion to reject backgrounds such as cosmic rays, asteroids, and subtraction artifacts. This leaves a large number of non-supernova candidates which must be verified by human inspection before triggering additional followup. In comparison to simple threshold cuts, more sophisticated methods such as boosted decision trees, random forests, and support vector machines provide dramatically better signal/background discrimination. At the SNfactory, we reduced the number of background candidates by a factor of 10 while increasing our supernova identification efficiency. Methods such as these will be crucial for handling the large data volumes produced by upcoming projects such as PanSTARRS and LSST.

  2. Agreement and association between different indicators of body image and body mass index in adolescents.

    Science.gov (United States)

    Santos, Carla Fernandez Dos; Castro, Inês Rugani Ribeiro de; Cardoso, Letícia de Oliveira; Tavares, Letícia Ferreira

    2014-01-01

    The aim of the study was to examine the correlation among different indicators of body image; between each one of these and nutritional status; and the association of these indicators with the Body Mass Index (BMI) of adolescents. A random sample of 152 students from public and private schools in the city of Rio de Janeiro, Brazil, was studied. On four occasions, two silhouette scales and two questions regarding the opinion of the student about his/her body and weight were applied and weight and height were measured. The BMI was examined both as a continuous and as a categorical variable. The agreement between the variables was analyzed using the quadratic weighted Kappa statistics. The association between body image variables and BMI was examined by the comparison among median, mean, standard deviation and 95% confidence interval of BMI for each category of the body image variables. In general, the correlation among the body image variables ranged from reasonable to good; between these and the variable nutritional status, correlation ranged from regular to reasonable. Best results were observed among boys and students from private schools. All body image variables showed good discriminatory power for BMI, when it was analyzed as a continuous variable, even when controlling for potential confounders. The question about body seems to be better than that about weight to compose the questionnaire of a surveillance system for risk and protective factors for adolescent health.

  3. Selectively detail-enhanced fusion of differently exposed images with moving objects.

    Science.gov (United States)

    Li, Zhengguo; Zheng, Jinghong; Zhu, Zijian; Wu, Shiqian

    2014-10-01

    In this paper, we introduce an exposure fusion scheme for differently exposed images with moving objects. The proposed scheme comprises a ghost removal algorithm in a low dynamic range domain and a selectively detail-enhanced exposure fusion algorithm. The proposed ghost removal algorithm includes a bidirectional normalization-based method for the detection of nonconsistent pixels and a two-round hybrid method for the correction of nonconsistent pixels. Our detail-enhanced exposure fusion algorithm includes a content adaptive bilateral filter, which extracts fine details from all the corrected images simultaneously in gradient domain. The final image is synthesized by selectively adding the extracted fine details to an intermediate image that is generated by fusing all the corrected images via an existing multiscale algorithm. The proposed exposure fusion algorithm allows fine details to be exaggerated while existing exposure fusion algorithms do not provide such an option. The proposed scheme usually outperforms existing exposure fusion schemes when there are moving objects in real scenes. In addition, the proposed ghost removal algorithm is simpler than existing ghost removal algorithms and is suitable for mobile devices with limited computational resource.

  4. Quantitative analysis of geomorphic processes using satellite image data at different scales

    Science.gov (United States)

    Williams, R. S., Jr.

    1985-01-01

    When aerial and satellite photographs and images are used in the quantitative analysis of geomorphic processes, either through direct observation of active processes or by analysis of landforms resulting from inferred active or dormant processes, a number of limitations in the use of such data must be considered. Active geomorphic processes work at different scales and rates. Therefore, the capability of imaging an active or dormant process depends primarily on the scale of the process and the spatial-resolution characteristic of the imaging system. Scale is an important factor in recording continuous and discontinuous active geomorphic processes, because what is not recorded will not be considered or even suspected in the analysis of orbital images. If the geomorphic process of landform change caused by the process is less than 200 m in x to y dimension, then it will not be recorded. Although the scale factor is critical, in the recording of discontinuous active geomorphic processes, the repeat interval of orbital-image acquisition of a planetary surface also is a consideration in order to capture a recurring short-lived geomorphic process or to record changes caused by either a continuous or a discontinuous geomorphic process.

  5. Radiopacity of restorative composites by conventional radiography and digital images with different resolutions

    Energy Technology Data Exchange (ETDEWEB)

    Dantas, Raquel Venancio; Samento, Hugo Ramalho [Graduate Program in Dentistry, Federal University of Pelotas, Pelotas (Brazil); Duarte, Rosangela Marques; Raso, Sonia Saeger Meireles Monte; De Andrade Ana Karina Maciel; Anjos-Pontual Maria Luiza Dos [Dept. of Operative Dentistry, Federal University of Paraiba, Pelotas (Brazil)

    2013-09-15

    This study was performed to evaluate and compare the radiopacity of dentin, enamel, and 8 restorative composites on conventional radiograph and digital images with different resolutions. Specimens were fabricated from 8 materials and human molars were longitudinally sectioned 1.0 mm thick to include both enamel and dentin. The specimens and tooth sections were imaged by conventional radiograph using 4 sized intraoral film and digital images were taken in high speed and high resolution modes using a phosphor storage plate. Densitometric evaluation of the enamel, dentin, restorative materials, a lead sheet, and an aluminum step wedge was performed on the radiographic images. For the evaluation, the Al equivalent (mm) for each material was calculated. The data were analyzed using one-way ANOVA and Tukey's test (p<0.05), considering the material factor and then the radiographic method factor, individually. The high speed mode allowed the highest radiopacity, while the high resolution mode generated the lowest values. Furthermore, the high resolution mode was the most efficient method for radiographic differentiation between restorative composites and dentin. The conventional radiograph was the most effective in enabling differentiation between enamel and composites. The high speed mode was the least effective in enabling radiographic differentiation between the dental tissues and restorative composites. The high speed mode of digital imaging was not effective for differentiation between enamel and composites. This made it less effective than the high resolution mode and conventional radiographs. All of the composites evaluated showed radiopacity values that fit the ISO 4049 recommendations.

  6. Agreement and association between different indicators of body image and body mass index in adolescents

    Directory of Open Access Journals (Sweden)

    Carla Fernandez dos Santos

    2014-09-01

    Full Text Available The aim of the study was to examine the correlation among different indicators of body image; between each one of these and nutritional status; and the association of these indicators with the Body Mass Index (BMI of adolescents. A random sample of 152 students from public and private schools in the city of Rio de Janeiro, Brazil, was studied. On four occasions, two silhouette scales and two questions regarding the opinion of the student about his/her body and weight were applied and weight and height were measured. The BMI was examined both as a continuous and as a categorical variable. The agreement between the variables was analyzed using the quadratic weighted Kappa statistics. The association between body image variables and BMI was examined by the comparison among median, mean, standard deviation and 95% confidence interval of BMI for each category of the body image variables. In general, the correlation among the body image variables ranged from reasonable to good; between these and the variable nutritional status, correlation ranged from regular to reasonable. Best results were observed among boys and students from private schools. All body image variables showed good discriminatory power for BMI, when it was analyzed as a continuous variable, even when controlling for potential confounders. The question about body seems to be better than that about weight to compose the questionnaire of a surveillance system for risk and protective factors for adolescent health.

  7. The infrared image simulation of the tank under different movement states

    Science.gov (United States)

    Gao, Xiang; Mu, Cheng-po; Peng, Ming-song; Dong, Qing-xian; Zhang, Rui-heng

    2017-07-01

    Tank, as a vital ground weapon, plays an irreplaceable role in the war. The article did the research of infrared image of the tank. Firstly, the 3D model of tank was established. And then the infrared radiation model of the target was constructed by analysing the infrared characteristics of the tank's different parts.. Finally the infrared radiation value of the tank under different states was calculated and the simulation of infrared characteristics of the tank under different states was done, which will provide reference for the research on infrared characteristics of the army's battlefield target.

  8. Cine Magnetic Resonance Imaging of the Small Bowel: Comparison of Different Oral Contrast Media

    Energy Technology Data Exchange (ETDEWEB)

    Asbach, P.; Breitwieser, C.; Diederichs, G.; Eisele, S.; Kivelitz, D.; Taupitz, M.; Zeitz, M.; Hamm, B.; Klessen, C. [Charite - Universitatsmedizin Berlin, Charite Campus Mitte, Berlin (Germany). Dept. of Radiology

    2006-11-15

    Purpose: To evaluate several substances regarding small bowel distension and contrast on balanced steady-state free precession (bSSFP) cine magnetic resonance (MR) images. Material and Methods: Luminal contrast was evaluated in 24 volunteers after oral application of two different contrast agent groups leading to either bright lumen (pineapple, blueberry juice) or dark lumen (tap water, orange juice) on T1-weighted images. Bowel distension was evaluated in 30 patients ingesting either methylcellulose or mannitol solution for limiting intestinal absorption. Fifteen patients with duodeno-jejunal intubation served as the control. Quantitative evaluation included measurement of luminal signal intensities and diameters of four bowel segments, qualitative evaluation assessed luminal contrast and distension on a five-point scale. Results: Quantitative and qualitative evaluation of the four contrast agents revealed no significant differences regarding luminal contrast on bSSFP images. Quantitative evaluation revealed significantly lower (P<0.05) small bowel distension for three out of four segments (qualitative evaluation: two out of four segments) for methylcellulose in comparison to the control. Mannitol was found to be equal to the control. Conclusion: Oral ingestion of tap water or orange juice in combination with mannitol is recommended for cine MR imaging of the small bowel regarding luminal contrast and small bowel distension on bSSFP sequences.

  9. Subjective and objective image differences in pediatric computed tomography cardiac angiography using lower iodine concentration

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Jae-Yeon [Pusan National University Yangsan Hospital, Department of Radiology, Yangsan-si, Gyeongsangnam-do (Korea, Republic of); Pusan National University Yangsan Hospital, Research Institute for Convergence of Biomedical Science and Technology, Yangsan-si, Gyeongsangnam-do (Korea, Republic of); Choo, Ki Seok; Choi, Yoon Young; Kim, Jin Hyeok; Ryu, Hwaseong; Kim, Yong-Woo; Jeon, Ung Bae; Nam, Kyung Jin [Pusan National University Yangsan Hospital, Department of Radiology, Yangsan-si, Gyeongsangnam-do (Korea, Republic of); Han, Junhee [Pusan National University Yangsan Hospital, Division of Biostatistics, Research Institute for Convergence of Biomedical Science and Technology, Yangsan-si, Gyeongsangnam-do (Korea, Republic of)

    2017-05-15

    Several recent studies showed the optimal contrast enhancement with a low-concentration and iso-osmolar contrast media in both adult and pediatric patients. However, low contrast media concentrations are not routinely used due to concerns of suboptimal enhancement of cardiac structures and small vessels. To evaluate the feasibility of using iso-osmolar contrast media containing a low iodine dose for CT cardiac angiography at 80 kilovolts (kVp) in neonates and infants. The iodixanol 270 group consisted of 79 CT scans and the iopromide 370 group of 62 CT scans in patients ≤1 year old. Objective measurement of the contrast enhancement was analyzed and contrast-to-noise ratios of the ascending aorta and left ventricle were calculated. Regarding subjective measurement, a four-point scale system was devised to evaluate degrees of contrast enhancement, image noise, motion artifact and overall image quality of each image set. Reader performance for correctly differentiating iodixanol 270 and iopromide 370 by visual assessment was evaluated. Group objective and subjective measurements were nonsignificantly different. Overall sensitivity, specificity and diagnostic accuracy for correctly differentiating iodixanol 270 and iopromide 370 by visual assessment were 42.8%, 59%, and 50%, respectively. The application of iodixanol 270 achieved optimal enhancement for performing pediatric cardiac CT angiography at 80 kVp in neonates and infants. Objective measurements of contrast enhancement and subjective image quality assessments were not statistically different in the iodixanol 270 and iopromide 370 groups. (orig.)

  10. Patch Similarity Modulus and Difference Curvature Based Fourth-Order Partial Differential Equation for Image Denoising

    Directory of Open Access Journals (Sweden)

    Yunjiao Bai

    2015-01-01

    Full Text Available The traditional fourth-order nonlinear diffusion denoising model suffers the isolated speckles and the loss of fine details in the processed image. For this reason, a new fourth-order partial differential equation based on the patch similarity modulus and the difference curvature is proposed for image denoising. First, based on the intensity similarity of neighbor pixels, this paper presents a new edge indicator called patch similarity modulus, which is strongly robust to noise. Furthermore, the difference curvature which can effectively distinguish between edges and noise is incorporated into the denoising algorithm to determine the diffusion process by adaptively adjusting the size of the diffusion coefficient. The experimental results show that the proposed algorithm can not only preserve edges and texture details, but also avoid isolated speckles and staircase effect while filtering out noise. And the proposed algorithm has a better performance for the images with abundant details. Additionally, the subjective visual quality and objective evaluation index of the denoised image obtained by the proposed algorithm are higher than the ones from the related methods.

  11. Vertical bone measurements from cone beam computed tomography images using different software packages

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcelos, Taruska Ventorini; Neves, Frederico Sampaio; Moraes, Livia Almeida Bueno; Freitas, Deborah Queiroz, E-mail: tataventorini@hotmail.com [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Faculdade de Odontologia

    2015-03-01

    This article aimed at comparing the accuracy of linear measurement tools of different commercial software packages. Eight fully edentulous dry mandibles were selected for this study. Incisor, canine, premolar, first molar and second molar regions were selected. Cone beam computed tomography (CBCT) images were obtained with i-CAT Next Generation. Linear bone measurements were performed by one observer on the cross-sectional images using three different software packages: XoranCat®, OnDemand3D® and KDIS3D®, all able to assess DICOM images. In addition, 25% of the sample was reevaluated for the purpose of reproducibility. The mandibles were sectioned to obtain the gold standard for each region. Intraclass coefficients (ICC) were calculated to examine the agreement between the two periods of evaluation; the one-way analysis of variance performed with the post-hoc Dunnett test was used to compare each of the software-derived measurements with the gold standard. The ICC values were excellent for all software packages. The least difference between the software-derived measurements and the gold standard was obtained with the OnDemand3D and KDIS3D (‑0.11 and ‑0.14 mm, respectively), and the greatest, with the XoranCAT (+0.25 mm). However, there was no statistical significant difference between the measurements obtained with the different software packages and the gold standard (p > 0.05). In conclusion, linear bone measurements were not influenced by the software package used to reconstruct the image from CBCT DICOM data. (author)

  12. SU-F-I-73: Surface Dose from KV Diagnostic Beams From An On-Board Imager On a Linac Machine Using Different Imaging Techniques and Filters

    Energy Technology Data Exchange (ETDEWEB)

    Ali, I; Hossain, S; Syzek, E; Ahmad, S [University of Oklahoma Health Sciences Center, Department of Radiation Oncology, Oklahoma City, OK (United States)

    2016-06-15

    Purpose: To quantitatively investigate the surface dose deposited in patients imaged with a kV on-board-imager mounted on a radiotherapy machine using different clinical imaging techniques and filters. Methods: A high sensitivity photon diode is used to measure the surface dose on central-axis and at an off-axis-point which is mounted on the top of a phantom setup. The dose is measured for different imaging techniques that include: AP-Pelvis, AP-Head, AP-Abdomen, AP-Thorax, and Extremity. The dose measurements from these imaging techniques are combined with various filtering techniques that include: no-filter (open-field), half-fan bowtie (HF), full-fan bowtie (FF) and Cu-plate filters. The relative surface dose for different imaging and filtering techniques is evaluated quantiatively by the ratio of the dose relative to the Cu-plate filter. Results: The lowest surface dose is deposited with the Cu-plate filter. The highest surface dose deposited results from open fields without filter and it is nearly a factor of 8–30 larger than the corresponding imaging technique with the Cu-plate filter. The AP-Abdomen technique delivers the largest surface dose that is nearly 2.7 times larger than the AP-Head technique. The smallest surface dose is obtained from the Extremity imaging technique. Imaging with bowtie filters decreases the surface dose by nearly 33% in comparison with the open field. The surface doses deposited with the HF or FF-bowtie filters are within few percentages. Image-quality of the radiographic images obtained from the different filtering techniques is similar because the Cu-plate eliminates low-energy photons. The HF- and FF-bowtie filters generate intensity-gradients in the radiographs which affects image-quality in the different imaging technique. Conclusion: Surface dose from kV-imaging decreases significantly with the Cu-plate and bowtie-filters compared to imaging without filters using open-field beams. The use of Cu-plate filter does not affect

  13. Image-based phenotyping for non-destructive screening of different salinity tolerance traits in rice

    KAUST Repository

    Hairmansis, Aris

    2014-08-14

    Background Soil salinity is an abiotic stress wide spread in rice producing areas, limiting both plant growth and yield. The development of salt-tolerant rice requires efficient and high-throughput screening techniques to identify promising lines for salt affected areas. Advances made in image-based phenotyping techniques provide an opportunity to use non-destructive imaging to screen for salinity tolerance traits in a wide range of germplasm in a reliable, quantitative and efficient way. However, the application of image-based phenotyping in the development of salt-tolerant rice remains limited. Results A non-destructive image-based phenotyping protocol to assess salinity tolerance traits of two rice cultivars (IR64 and Fatmawati) has been established in this study. The response of rice to different levels of salt stress was quantified over time based on total shoot area and senescent shoot area, calculated from visible red-green-blue (RGB) and fluorescence images. The response of rice to salt stress (50, 75 and 100 mM NaCl) could be clearly distinguished from the control as indicated by the reduced increase of shoot area. The salt concentrations used had only a small effect on the growth of rice during the initial phase of stress, the shoot Na+ accumulation independent phase termed the ‘osmotic stress’ phase. However, after 20 d of treatment, the shoot area of salt stressed plants was reduced compared with non-stressed plants. This was accompanied by a significant increase in the concentration of Na+ in the shoot. Variation in the senescent area of the cultivars IR64 and Fatmawati in response to a high concentration of Na+ in the shoot indicates variation in tissue tolerance mechanisms between the cultivars. Conclusions Image analysis has the potential to be used for high-throughput screening procedures in the development of salt-tolerant rice. The ability of image analysis to discriminate between the different aspects of salt stress (shoot ion

  14. A fast time-difference inverse solver for 3D EIT with application to lung imaging.

    Science.gov (United States)

    Javaherian, Ashkan; Soleimani, Manuchehr; Moeller, Knut

    2016-08-01

    A class of sparse optimization techniques that require solely matrix-vector products, rather than an explicit access to the forward matrix and its transpose, has been paid much attention in the recent decade for dealing with large-scale inverse problems. This study tailors application of the so-called Gradient Projection for Sparse Reconstruction (GPSR) to large-scale time-difference three-dimensional electrical impedance tomography (3D EIT). 3D EIT typically suffers from the need for a large number of voxels to cover the whole domain, so its application to real-time imaging, for example monitoring of lung function, remains scarce since the large number of degrees of freedom of the problem extremely increases storage space and reconstruction time. This study shows the great potential of the GPSR for large-size time-difference 3D EIT. Further studies are needed to improve its accuracy for imaging small-size anomalies.

  15. Images

    Data.gov (United States)

    National Aeronautics and Space Administration — Images for the website main pages and all configurations. The upload and access points for the other images are: Website Template RSW images BSCW Images HIRENASD...

  16. Neonatal infrared thermography imaging: Analysis of heat flux during different clinical scenarios

    Science.gov (United States)

    Abbas, Abbas K.; Heimann, Konrad; Blazek, Vladimir; Orlikowsky, Thorsten; Leonhardt, Steffen

    2012-11-01

    IntroductionAn accurate skin temperature measurement of Neonatal Infrared Thermography (NIRT) imaging requires an appropriate calibration process for compensation of external effects (e.g. variation of environmental temperature, variable air velocity or humidity). Although modern infrared cameras can perform such calibration, an additional compensation is required for highly accurate thermography. This compensation which corrects any temperature drift should occur during the NIRT imaging process. We introduce a compensation technique which is based on modeling the physical interactions within the measurement scene and derived the detected temperature signal of the object. Materials and methodsIn this work such compensation was performed for different NIRT imaging application in neonatology (e.g. convective incubators, kangaroo mother care (KMC), and an open radiant warmer). The spatially distributed temperatures of 12 preterm infants (average gestation age 31 weeks) were measured under these different infant care arrangements (i.e. closed care system like a convective incubator, and open care system like kangaroo mother care, and open radiant warmer). ResultsAs errors in measurement of temperature were anticipated, a novel compensation method derived from infrared thermography of the neonate's skin was developed. Moreover, the differences in temperature recording for the 12 preterm infants varied from subject to subject. This variation could be arising from individual experimental setting applied to the same region of interest over the neonate's body. The experimental results for the model-based corrections is verified over the selected patient group. ConclusionThe proposed technique relies on applying model-based correction to the measured temperature and reducing extraneous errors during NIRT. This application specific method is based on different heat flux compartments present in neonatal thermography scene. Furthermore, these results are considered to be

  17. Accounting for pharmacokinetic differences in dual-tracer receptor density imaging

    OpenAIRE

    Tichauer, K M; Diop, M.; Elliott, J. T.; Samkoe, K S; Hasan, T.; St. Lawrence, K; Pogue, B W

    2014-01-01

    Dual-tracer molecular imaging is a powerful approach to quantify receptor expression in a wide range of tissues by using an untargeted tracer to account for any nonspecific uptake of a molecular-targeted tracer. This approach has previously required the pharmacokinetics of the receptor-targeted and untargeted tracers to be identical, requiring careful selection of an ideal untargeted tracer for any given targeted tracer. In this study, methodology capable of correcting for tracer differences ...

  18. Exact ray-tracing computation of narcissus-equivalent temperature difference in scanning thermal imagers

    Science.gov (United States)

    Rayces, Juan L.; Lebich, Lan

    1992-12-01

    The formula for evaluation of narcissus equivalent temperature difference as a function of the scan angle in thermal imaging systems is made more meaningful by grouping the parameters in two factors: one depending on wavelength and temperature and the other, a function of the scan angle, depending on the geometry of the instrument. Exact ray tracing equations are used to evaluate the ratio of radiant energy reaching the detector from warm and cold areas of the instrument.

  19. Three-dimensional ultrasonic imaging of concrete elements using different SAFT data acquisition and processing schemes

    Energy Technology Data Exchange (ETDEWEB)

    Schickert, Martin, E-mail: martin.schickert@mfpa.de [Materialforschungs- und -prüfanstalt an der Bauhaus-Universität Weimar, Coudraystr. 9, 99425 Weimar (Germany)

    2015-03-31

    Ultrasonic testing systems using transducer arrays and the SAFT (Synthetic Aperture Focusing Technique) reconstruction allow for imaging the internal structure of concrete elements. At one-sided access, three-dimensional representations of the concrete volume can be reconstructed in relatively great detail, permitting to detect and localize objects such as construction elements, built-in components, and flaws. Different SAFT data acquisition and processing schemes can be utilized which differ in terms of the measuring and computational effort and the reconstruction result. In this contribution, two methods are compared with respect to their principle of operation and their imaging characteristics. The first method is the conventional single-channel SAFT algorithm which is implemented using a virtual transducer that is moved within a transducer array by electronic switching. The second method is the Combinational SAFT algorithm (C-SAFT), also named Sampling Phased Array (SPA) or Full Matrix Capture/Total Focusing Method (TFM/FMC), which is realized using a combination of virtual transducers within a transducer array. Five variants of these two methods are compared by means of measurements obtained at test specimens containing objects typical of concrete elements. The automated SAFT imaging system FLEXUS is used for the measurements which includes a three-axis scanner with a 1.0 m × 0.8 m scan range and an electronically switched ultrasonic array consisting of 48 transducers in 16 groups. On the basis of two-dimensional and three-dimensional reconstructed images, qualitative and some quantitative results of the parameters image resolution, signal-to-noise ratio, measurement time, and computational effort are discussed in view of application characteristics of the SAFT variants.

  20. Evaluation of clip localization for different kilovoltage imaging modalities as applied to partial breast irradiation setup

    Energy Technology Data Exchange (ETDEWEB)

    Buehler, Andreas; Ng, Sook-Kien; Lyatskaya, Yulia; Stsepankou, Dzmitry; Hesser, Jurgen; Zygmanski, Piotr [University Medical Centre Mannheim, University of Heidelberg, Theodor-Kutzer Ufer 1-3, D-68167 Mannheim (Germany); Department of Radiation Oncology and Brigham and Women' s Hospital, and Harvard Medical School, Boston, Massachusetts 02115 (United States); University Medical Centre Mannheim, University of Heidelberg, Theodor-Kutzer Ufer 1-3, D-68167 Mannheim (Germany); Department of Radiation Oncology and Brigham and Women' s Hospital, and Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2009-03-15

    Surgical clip localization and image quality were evaluated for different types of kilovoltage cone beam imaging modalities as applied to partial breast irradiation (PBI) setup. These modalities included (i) clinically available radiographs and cone beam CT (CB-CT) and (ii) various alternative modalities based on partial/sparse/truncated CB-CT. An anthropomorphic torso-breast phantom with surgical clips was used for the imaging studies. The torso phantom had artificial lungs, and the attached breast phantom was a mammographic phantom with realistic shape and tissue inhomogeneities. Three types of clips of variable size were used in two orthogonal orientations to assess their in-/cross-plane characteristics for image-guided setup of the torso-breast phantom in supine position. All studies were performed with the Varian on-board imaging (OBI, Varian) system. CT reconstructions were calculated with the standard Feldkamp-Davis-Kress algorithm. First, the radiographs were studied for a wide range of viewing angles to characterize image quality for various types of body anatomy in the foreground/background of the clips. Next, image reconstruction quality was evaluated for partial/sparse/truncated CB-CT. Since these modalities led to reconstructions with strong artifacts due to insufficient input data, a knowledge-based CT reconstruction method was also tested. In this method, the input data to the reconstruction algorithm were modified by combining complementary data sets selected from the treatment and reference projections. Different partial/sparse/truncated CB-CT scan types were studied depending on the total arc angle, angular increment between the consequent views (CT projections), orientation of the arc center with respect to the imaged breast and chest wall, and imaging field size. The central angles of the viewing arcs were either tangential or orthogonal to the chest wall. Several offset positions of the phantom with respect to the reference position were

  1. Super-resolution reconstruction of diffusion parameters from diffusion-weighted images with different slice orientations.

    Science.gov (United States)

    Van Steenkiste, Gwendolyn; Jeurissen, Ben; Veraart, Jelle; den Dekker, Arnold J; Parizel, Paul M; Poot, Dirk H J; Sijbers, Jan

    2016-01-01

    Diffusion MRI is hampered by long acquisition times, low spatial resolution, and a low signal-to-noise ratio. Recently, methods have been proposed to improve the trade-off between spatial resolution, signal-to-noise ratio, and acquisition time of diffusion-weighted images via super-resolution reconstruction (SRR) techniques. However, during the reconstruction, these SRR methods neglect the q-space relation between the different diffusion-weighted images. An SRR method that includes a diffusion model and directly reconstructs high resolution diffusion parameters from a set of low resolution diffusion-weighted images was proposed. Our method allows an arbitrary combination of diffusion gradient directions and slice orientations for the low resolution diffusion-weighted images, optimally samples the q- and k-space, and performs motion correction with b-matrix rotation. Experiments with synthetic data and in vivo human brain data show an increase of spatial resolution of the diffusion parameters, while preserving a high signal-to-noise ratio and low scan time. Moreover, the proposed SRR method outperforms the previous methods in terms of the root-mean-square error. The proposed SRR method substantially increases the spatial resolution of MRI that can be obtained in a clinically feasible scan time. © 2015 Wiley Periodicals, Inc.

  2. Imaging findings of hepatic focal nodular hyperplasia in men and women: are they really different?

    Science.gov (United States)

    Bartolotta, Tommaso Vincenzo; Taibbi, Adele; Brancatelli, Giuseppe; Matranga, Domenica; Tumbarello, Marisa; Midiri, Massimo; Lagalla, Roberto

    2014-04-01

    This study was undertaken to compare the imaging findings of focal nodular hyperplasia (FNH) in men and women, as seen on multidetector computed tomography (MDCT), magnetic resonance imaging (MRI) and contrast-enhanced ultrasound (CEUS). Two radiologists reviewed 195 imaging studies (17 MDCT, 81 MRI and 97 CEUS examinations) pertaining to 111 FNHs (mean size 3 cm) in 91 patients (mean age 39 years). For each lesion, the readers assessed size, location, echogenicity, attenuation, or signal intensity in comparison with adjacent liver parenchyma on both unenhanced and postcontrast images. Eighty-nine FNHs (mean size 3.1 cm) were observed in 73 women (mean age 37.9 years) and 22 FNHs (mean size 2.7 cm) in 18 men (mean age 41.2 years). No statistically significant differences were found between men and women in terms of age, FNH lesions per patient (1.22 and 1.21, respectively), size, baseline and enhancement pattern on MRI, CEUS and MDCT (p men and 16/63 (25.4%) women on MRI (p men and 7/15 (46.7%) women on MDCT (p wheel pattern, central scar, and/or feeding vessel were seen in 5/17 (29.4%) men and 22/80 (27.5%) women on CEUS (p men and women.

  3. Evaluation of the clinical practicability of intraoperative optical imaging comparing three different camera setups.

    Science.gov (United States)

    Sobottka, Stephan B; Meyer, Tobias; Kirsch, Matthias; Koch, Edmund; Steinmeier, Ralf; Morgenstern, Ute; Schackert, Gabriele

    2013-06-01

    Intraoperative optical imaging (IOI) is a method to visualize functional activated brain areas during brain surgery using a camera system connected to a standard operating microscope. Three different high-resolution camera systems (Hamamatsu EB-CCD C7190-13W, Hamamatsu C4742-96-12G04, and Zeiss AxioCam MRm) have been evaluated for suitability to detect activated brain areas by detecting stimulation-dependent blood volume changes in the somatosensory cerebral cortex after median nerve stimulation. The image quality of the camera systems was evaluated in 14 patients with tumors around the somatosensory cortex. The intraoperative images of the brain surface were continuously recorded over 9 min. With all three camera systems, the activity maps of the median nerve area could be visualized. The image quality of a highly sensitive electron-bombarded camera was up to 10-fold lower compared with two less sensitive standard cameras. In each IOI-positive case, the activated area was in accordance with the anatomical and neurophysiological location of the corresponding cortex. The technique was found to be very sensitive, and several negative influencing factors were identified. However, all possible artifacts seem to be controllable in the majority of the cases, and the IOI method could be well adapted for routine clinical use. Nevertheless, further systematic studies are needed to demonstrate the reliability and validity of the method.

  4. Diagnostic accuracy of different imaging modalities in detection of proximal caries.

    Science.gov (United States)

    Senel, B; Kamburoglu, K; Uçok, O; Yüksel, S P; Ozen, T; Avsever, H

    2010-12-01

    The purpose of this study was to assess the in vitro diagnostic ability of visual inspection, film, charge-coupled device (CCD) sensor, photostimulable phosphor (PSP) sensor and cone beam CT in the detection of proximal caries in posterior teeth compared with the histological gold standard. Visual inspection, film, CCD, PSP and cone beam CT images were used to detect proximal caries in the mesial and distal surfaces of 138 teeth (276 surfaces). Visual inspection and evaluation of all intraoral digital and conventional radiographs and cone beam CT images were performed twice by three oral radiologists. Weighted kappa coefficients were calculated to assess intra- and interobserver agreement for each image set, and scores were compared with the histological gold standard using receiver operating characteristic (ROC) analysis to evaluate diagnostic ability. Intraobserver kappa coefficients calculated for each observer for each method of detecting caries ranged from 0.739 to 0.928. Strong interobserver agreement ranging from 0.631 to 0.811 was found for all detection methods. The highest Az values for all three observers were obtained with the cone beam CT images; however, differences between detection methods were not statistically significant (P > 0.05). Visual inspection, film, CCD, PSP plates and cone beam CT performed similarly in the detection of proximal caries.

  5. Effects of different tube potentials and iodine concentrations on image enhancement, contrast-to-noise ratio and noise in micro-CT images: a phantom study.

    Science.gov (United States)

    Abdul Razak, Hairil Rashmizal; Shaffiq Said Rahmat, Said Mohd; Md Saad, Wan Mazlina

    2013-10-01

    The study aimed to investigate the effects of different tube potentials and concentrations of iodinated contrast media (CM) on the image enhancement, contrast-to-noise ratio (CNR) and noise in micro-computed tomography (µCT) images. A phantom containing of five polyethylene tube was filled with 2 mL of deionized water and iodinated CM (Omnipaque 300 mgI/mL) at four different concentrations: 5, 10, 15, and 20 mol/L, respectively. The phantom was scanned with a µCT machine (SkyScan 1176) using various tube potentials: 40, 50, 60, 70, 80, and 90 kVp, a fixed tube current; 100 µA, and filtration of 0.2 mm aluminum (Al). The percentage difference of image enhancement, CNR and noise of all images, acquired at different kVps and concentrations, were calculated. The image enhancement, CNR and noise curves with respect to tube potential and concentration were plotted and analysed. The highest image enhancement was found at the lowest tube potential of 40 kVp. At this kVp setting, the percentage difference of image enhancement [Hounsfield Unit (HU) of 20 mol/L iodine concentration over HU of deionized water] was 43%. By increasing the tube potential, it resulted with the reduction of HU, where only 17.5% different were noticed for 90 kVp. Across all iodine concentrations (5-20 M), CNR peaked at 80 kVp and then these values showed a slight decreasing pattern, which might be due insufficient tube current compensation. The percentage difference of image noise obtained at 40 and 90 kVp was 72.4%. Lower tube potential setting results in higher image enhancement (HU) in conjunction with increasing concentration of iodinated CM. Overall, the tube potential increment will substantially improve CNR and reduce image noise.

  6. Comparison of different methods of image analysis for quantifying bare soil in rangelands

    Science.gov (United States)

    Pulido Fernández, M.; Lavado Contador, J. F.; Schnabel, S.; Gómez Gutiérrez, Á.

    2009-04-01

    Many authors emphasize the importance of vegetation in maintaining low levels of soil loss by means of its positive influence in reducing erosion. In some low-vegetated Mediterranean rangelands, especially those with high livestock densities, water erosion can ultimately lead to a partial or total loss of soils, particularly at the beginning of the rainy season, when the surface cover is reduced after the dry summer period. In relation with this, it is essential to develop accurate methods allowing the quantification of bare soil which, in turn, can inform about the influence of different livestock management alternatives over the land system. The main goal of this work is the comparison of the ability of various pixel-based as well as object-oriented methods of image classification for the quantification of bare soil at a fine spatial resolution. The study area is a farm located in a woody rangeland (dehesa) in SW Spain covering a surface area of 1,024 hectare. A three bands (RGB) orthophoto image with a pixel size of 0,4 metres was used, together with its brightness component, to compare the classification of bare soil vs covered soil by means of the following methods: unsupervised classification (k-means algorithm), supervised classification (maximum likelihood classification, minimum distance or nearest neighbour and Mahalanobis distance) and object oriented classification through a multiresolution segmentation. The results of classification were tested using 700 to 1000 points of field validation. Different combinations of image layers as well as validation algorithms were applied to assess for the better classification results. The best unsupervised classification was obtained from a combination of the RGB layers with the brightness component of the image. A total of 93.1 % of the field data were correctly classified and the Area Under the Curve (AUC) obtained with the ROC (Receiving Operating Characteristic) validation technique amounted to 0.91. With this

  7. AN EVALUATION OF DIFFERENT METHODS FOR MEASURING LATERAL TIBIAL SLOPE USING MAGNETIC RESONANCE IMAGING

    Science.gov (United States)

    Lipps, David B.; Wilson, Annie M.; Ashton-Miller, James A.; Wojtys, Edward M.

    2014-01-01

    Background Since lateral tibial slope (LTS) affects the amount of anterior tibial translation and anterior cruciate ligament (ACL) strain during a dynamic maneuver, accurate measurements of lateral tibial slope may be beneficial in screening individuals at a higher risk for ACL injury. Methods for measuring LTS on magnetic resonance imaging scans of the proximal tibia include the midpoint and circle methods. There are no current studies that have validated different LTS measurements methods using a proximal tibia magnetic resonance imaging scan. Hypothesis We tested the null hypotheses that (1) LTS measurements were independent of the length of tibia imaged using the midpoint method, and (2) LTS measurements calculated from different methods (‘midpoint’, ‘circle’, and ‘full tibia’) would not differ significantly. Study Design Descriptive Laboratory Study Methods Blinded observers measured LTS from 3-Tesla 3D magnetic resonance images from 40 size-matched donors according to one circle method and three midpoint methods. Outcomes were then compared to the full tibial anatomical axis (line connecting the center of two circles fit within the proximal and distal tibia) in 11 donors. Bonferroni-correct paired t-tests (p methods. Results The circle and full tibia methods had the lowest inter- and intra-observer variability, while the midpoint method with 10 cm tibia was the most variable. The midpoint method with 10cm and 15 cm proximal tibia closely resembled LTS measurements with the full tibia anatomic axis. The circle method, while repeatable, provided smaller numerical LTS measurements than the full tibia and midpoint methods. Conclusions While LTS measurements using the midpoint method can resemble measurements made using the full tibia, the reliability of the midpoint method depends on the length of proximal tibia used. The circle method may be the preferred method for future studies since it was the most repeatable method and is independent of proximal

  8. Comparison between two different algorithms used for pretreatment QA via aSi portal images.

    Science.gov (United States)

    Merheb, Charbel; Chevillard, Clément; Ksouri, Wassim; Fawzi, Maher; Bollet, Marc; Toledano, Alain

    2015-05-08

    Several algorithms exist to perform quality assurance for volumetric-modulated arc therapy (VMAT) treatments based on electronic portal imaging devices (EPID). These algorithms are used to compare doses (convert into water, GLAaS) and fluences (in amorphous silicon (aSi), Varian portal dosimetry). The aim of this study is to compare the two methods using clinical data. In this study, Varian portal dosimetry (VPD) and Epiqa solutions were compared. We used a same set of patient images data treated with 6 MV and 20 MV photon energies and different locations. The response of the portal imaging device was also investigated with different field sizes, monitor units, dose rates, sag effect, and linac daily output. All images were acquired on an electronic portal imaging device (EPID) positioned at source detector distance (SDD) of 100 cm. A virtual water phantom was used for Epiqa to calculate the dose matrices at the maximum depth doses dmax. The 2D gamma evaluation index (GAI) was performed to quantitatively compare the results given by the two solutions. The response of the EPID gave a good agreement with Epiqa (deviation less than 1%) for MU greater than 20 for both 6 MV and 20 MV photon energies. For VPD, the upward sloping trend showed a good agreement for MU higher than 50. Dose rate evaluations for both methods gave a deviation of, respectively, 0.4 and 0.5 % for 6 MV and 20 MV. The gamma criteria of 3 mm for distance to agreement and 3 % for dose difference was, as mean ± 1SD, 99.81% ± 1.48% and 99.42% ± 0.97% for VPD and Epiqa, respectively, for 6 MV photon energy. The mean values of the gamma criteria for the collected data using 20 MV photon energy were, respectively, 98.33% ± 2.41% and 98.12% ± 1.99% for VPD and Epiqa. The output constancy deviation correction (a 10 × 10cm² reference field plan to obtain absorbed dose despite the linac monitor daily variations) showed a mean deviation of, respectively, 0.07% ± 0.57% and 0.16% ± 1.38% for 6 MV and 20

  9. Color measurement of tea leaves at different drying periods using hyperspectral imaging technique.

    Directory of Open Access Journals (Sweden)

    Chuanqi Xie

    Full Text Available This study investigated the feasibility of using hyperspectral imaging technique for nondestructive measurement of color components (ΔL*, Δa* and Δb* and classify tea leaves during different drying periods. Hyperspectral images of tea leaves at five drying periods were acquired in the spectral region of 380-1030 nm. The three color features were measured by the colorimeter. Different preprocessing algorithms were applied to select the best one in accordance with the prediction results of partial least squares regression (PLSR models. Competitive adaptive reweighted sampling (CARS and successive projections algorithm (SPA were used to identify the effective wavelengths, respectively. Different models (least squares-support vector machine [LS-SVM], PLSR, principal components regression [PCR] and multiple linear regression [MLR] were established to predict the three color components, respectively. SPA-LS-SVM model performed excellently with the correlation coefficient (rp of 0.929 for ΔL*, 0.849 for Δa*and 0.917 for Δb*, respectively. LS-SVM model was built for the classification of different tea leaves. The correct classification rates (CCRs ranged from 89.29% to 100% in the calibration set and from 71.43% to 100% in the prediction set, respectively. The total classification results were 96.43% in the calibration set and 85.71% in the prediction set. The result showed that hyperspectral imaging technique could be used as an objective and nondestructive method to determine color features and classify tea leaves at different drying periods.

  10. Comparing Image Perception of Bladder Tumors in Four Different Storz Professional Image Enhancement System Modalities Using the íSPIES App

    NARCIS (Netherlands)

    Kamphuis, Guido M.; de Bruin, D. Martijn; Brandt, Martin J.; Knoll, Thomas; Conort, Pierre; Lapini, Alberto; Dominguez-Escrig, Jose L.; de La Rosette, Jean J. M. C. H.

    2016-01-01

    To evaluate the variation of interpretation of the same bladder urothelium image in different Storz Professional Image Enhancement System (SPIES) modalities. SPIES contains a White light (WL), Spectra A (SA), Spectra B (SB), and Clara and Chroma combined (CC) modality. An App for the iPAD retina was

  11. Overview about the localization of nanoparticles in tissue and cellular context by different imaging techniques

    Directory of Open Access Journals (Sweden)

    Anja Ostrowski

    2015-01-01

    Full Text Available The increasing interest and recent developments in nanotechnology pose previously unparalleled challenges in understanding the effects of nanoparticles on living tissues. Despite significant progress in in vitro cell and tissue culture technologies, observations on particle distribution and tissue responses in whole organisms are still indispensable. In addition to a thorough understanding of complex tissue responses which is the domain of expert pathologists, the localization of particles at their sites of interaction with living structures is essential to complete the picture. In this review we will describe and compare different imaging techniques for localizing inorganic as well as organic nanoparticles in tissues, cells and subcellular compartments. The visualization techniques include well-established methods, such as standard light, fluorescence, transmission electron and scanning electron microscopy as well as more recent developments, such as light and electron microscopic autoradiography, fluorescence lifetime imaging, spectral imaging and linear unmixing, superresolution structured illumination, Raman microspectroscopy and X-ray microscopy. Importantly, all methodologies described allow for the simultaneous visualization of nanoparticles and evaluation of cell and tissue changes that are of prime interest for toxicopathologic studies. However, the different approaches vary in terms of applicability for specific particles, sensitivity, optical resolution, technical requirements and thus availability, and effects of labeling on particle properties. Specific bottle necks of each technology are discussed in detail. Interpretation of particle localization data from any of these techniques should therefore respect their specific merits and limitations as no single approach combines all desired properties.

  12. Individual differences in processing emotional images after reading disgusting and neutral sentences.

    Science.gov (United States)

    Hartigan, Alex; Richards, Anne

    2017-11-21

    The present study examined the extent to which Event Related Potentials (ERPs) evoked by disgusting, threatening and neutral photographic images were influenced by disgust propensity, disgust sensitivity and attentional control following exposure to disgusting information. Emotional cognition was manipulated by instructing participants to remember either disgusting or neutral sentences; participants in both groups then viewed emotional images while ERPs were recorded. Disgust propensity was associated with a reduced Late Positive Potential (LPP) gap between threatening and neutral stimuli (an effect driven by a rise in the LPP for neutral images) but only amongst individuals who were exposed to disgusting sentences. The typical LPP increase for disgust over neutral was reduced by attentional shifting capacity but only for individuals who were not previously exposed to disgust. There was also a persistent occipital shifted late positivity that was enhanced for disgust for the entire LPP window and was independent of exposure. Results suggest that emotion specific ERP effects can emerge within the broad unpleasant emotional category in conjunction with individual differences and prior emotional exposure. These results have important implications for the ways in which the perception of emotion is impacted by short term cognitive influences and longer term individual differences. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. A comparison with result of normalized image to different template image on statistical parametric mapping of ADHD children patients

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Dong Ho [Kyonggi University, Suwon (Korea, Republic of); Park, Soung Ock; Kwon, Soo Il [Dongnam Health College, Suwon (Korea, Republic of); Joh, Chol Woo; Yoon, Seok Nam [Medical College, Ajou University, Suwon (Korea, Republic of)

    2003-06-15

    We studied 64 ADHD children patients group (4 {approx} 15 ys, mean age: 8 {+-} 2.6 ys. M/F: 52/12) and 12 normal group (6 {approx} 7 ys, mean age: 9.4 {+-} 3.4 ys, M/F: 8/4) of the brain had been used to analysis of blood flow between normal and ADHD group. For analysis of Children ADHD, we used 12 children's mean brain images and made Template image of SPM99 program. In crease of blood flow (P-value 0.05), the result of normalized images to Template image to offer from SPM99 program, showed significant cluster in inter-Hemispheric and occipital Lobe, in the case of normalized images to children template image, showed inter-hemispheric and parietal lobe.

  14. THE DIFFERENCE IMAGING PIPELINE FOR THE TRANSIENT SEARCH IN THE DARK ENERGY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, R.; Scolnic, D. [Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637 (United States); Marriner, J.; Finley, D. A.; Wester, W. [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Childress, M.; Yuan, F. [ARC Centre of Excellence for All-sky Astrophysics (CAASTRO), Australian National University, Canberra ACT 2611 (Canada); Covarrubias, R. [National Center for Supercomputing Applications, 1205 West Clark St., Urbana, IL 61801 (United States); D’Andrea, C. B.; Nichol, R. C.; Papadopoulos, A. [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom); Fischer, J.; Sako, M. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States); Foley, R. J. [Department of Astronomy, University of Illinois, 1002 W. Green Street, Urbana, IL 61801 (United States); Goldstein, D. [Department of Astronomy, University of California, Berkeley, 501 Campbell Hall, Berkeley, CA 94720 (United States); Gupta, R. R. [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States); Kuehn, K. [Australian Astronomical Observatory, North Ryde, NSW 2113 (Australia); Marcha, M. [Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT (United Kingdom); Smith, M.; Sullivan, M., E-mail: kessler@kicp.uchicago.edu [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom); Collaboration: DES Collaboration; and others

    2015-12-15

    We describe the operation and performance of the difference imaging pipeline (DiffImg) used to detect transients in deep images from the Dark Energy Survey Supernova program (DES-SN) in its first observing season from 2013 August through 2014 February. DES-SN is a search for transients in which ten 3 deg{sup 2} fields are repeatedly observed in the g, r, i, z passbands with a cadence of about 1 week. The observing strategy has been optimized to measure high-quality light curves and redshifts for thousands of Type Ia supernovae (SNe Ia) with the goal of measuring dark energy parameters. The essential DiffImg functions are to align each search image to a deep reference image, do a pixel-by-pixel subtraction, and then examine the subtracted image for significant positive detections of point-source objects. The vast majority of detections are subtraction artifacts, but after selection requirements and image filtering with an automated scanning program, there are ∼130 detections per deg{sup 2} per observation in each band, of which only ∼25% are artifacts. Of the ∼7500 transients discovered by DES-SN in its first observing season, each requiring a detection on at least two separate nights, Monte Carlo (MC) simulations predict that 27% are expected to be SNe Ia or core-collapse SNe. Another ∼30% of the transients are artifacts in which a small number of observations satisfy the selection criteria for a single-epoch detection. Spectroscopic analysis shows that most of the remaining transients are AGNs and variable stars. Fake SNe Ia are overlaid onto the images to rigorously evaluate detection efficiencies and to understand the DiffImg performance. The DiffImg efficiency measured with fake SNe agrees well with expectations from a MC simulation that uses analytical calculations of the fluxes and their uncertainties. In our 8 “shallow” fields with single-epoch 50% completeness depth ∼23.5, the SN Ia efficiency falls to 1/2 at redshift z ≈ 0.7; in our 2

  15. THE DIFFERENCE IMAGING PIPELINE FOR THE TRANSIENT SEARCH IN THE DARK ENERGY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, R.; Marriner, J.; Childress, M.; Covarrubias, R.; D’Andrea, C. B.; Finley, D. A.; Fischer, J.; Foley, R. J.; Goldstein, D.; Gupta, R. R.; Kuehn, K.; Marcha, M.; Nichol, R. C.; Papadopoulos, A.; Sako, M.; Scolnic, D.; Smith, M.; Sullivan, M.; Wester, W.; Yuan, F.; Abbott, T.; Abdalla, F. B.; Allam, S.; Benoit-Lévy, A.; Bernstein, G. M.; Bertin, E.; Brooks, D.; Rosell, A. Carnero; Kind, M. Carrasco; Castander, F. J.; Crocce, M.; Costa, L. N. da; Desai, S.; Diehl, H. T.; Eifler, T. F.; Neto, A. Fausti; Flaugher, B.; Frieman, J.; Gerdes, D. W.; Gruen, D.; Gruendl, R. A.; Honscheid, K.; James, D. J.; Kuropatkin, N.; Li, T. S.; Maia, M. A. G.; Marshall, J. L.; Martini, P.; Miller, C. J.; Miquel, R.; Nord, B.; Ogando, R.; Plazas, A. A.; Reil, K.; Romer, A. K.; Roodman, A.; Sanchez, E.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Tarle, G.; Thaler, J.; Thomas, R. C.; Tucker, D.; Walker, A. R.

    2015-11-06

    We describe the operation and performance of the difference imaging pipeline (DiffImg) used to detect transients in deep images from the Dark Energy Survey Supernova program (DES-SN) in its first observing season from 2013 August through 2014 February. DES-SN is a search for transients in which ten 3 deg(2) fields are repeatedly observed in the g, r, i, z passbands with a cadence of about 1 week. The observing strategy has been optimized to measure high-quality light curves and redshifts for thousands of Type Ia supernovae (SNe Ia) with the goal of measuring dark energy parameters. The essential DiffImg functions are to align each search image to a deep reference image, do a pixel-by-pixel subtraction, and then examine the subtracted image for significant positive detections of point-source objects. The vast majority of detections are subtraction artifacts, but after selection requirements and image filtering with an automated scanning program, there are similar to 130 detections per deg(2) per observation in each band, of which only similar to 25% are artifacts. Of the similar to 7500 transients discovered by DES-SN in its first observing season, each requiring a detection on at least two separate nights, Monte Carlo (MC) simulations predict that 27% are expected to be SNe Ia or core-collapse SNe. Another similar to 30% of the transients are artifacts in which a small number of observations satisfy the selection criteria for a single-epoch detection. Spectroscopic analysis shows that most of the remaining transients are AGNs and variable stars. Fake SNe Ia are overlaid onto the images to rigorously evaluate detection efficiencies and to understand the DiffImg performance. The DiffImg efficiency measured with fake SNe agrees well with expectations from a MC simulation that uses analytical calculations of the fluxes and their uncertainties. In our 8 "shallow" fields with single-epoch 50% completeness depth similar to 23.5, the SN Ia efficiency falls to 1/2 at

  16. Shear strain determination of the polymer polydimethysiloxane (PMDS) using digital image correlation in different temperatures

    Science.gov (United States)

    de Oliveira, G. N.; Nunes, L. C. S.; dos Santos, P. A. M.

    2011-01-01

    In the present work a digital image correlation (DIC) method is used in order to analyze the adhesive shear modulus of poly-dimethylsiloxane (PDMS) submitted to different loads and temperatures. This is an optical-numerical full-field surface displacement measurement method. It is based on a comparison between two images of a specimen coated by a random speckled pattern in the undeformed and in the deformed states. A single lap joint testing is performed. This is a standard test specimen for characterizing adhesive properties and it is considered the simplest form of adhesive joints. For the single lap joint specimen, steel adherends are bonded using a flexible rubber elastic polymer (PDMS), which is a commercially available silicone elastic rubber

  17. Comparison of Different Post-Processing Algorithms for Dynamic Susceptibility Contrast Perfusion Imaging of Cerebral Gliomas.

    Science.gov (United States)

    Kudo, Kohsuke; Uwano, Ikuko; Hirai, Toshinori; Murakami, Ryuji; Nakamura, Hideo; Fujima, Noriyuki; Yamashita, Fumio; Goodwin, Jonathan; Higuchi, Satomi; Sasaki, Makoto

    2017-04-10

    The purpose of the present study was to compare different software algorithms for processing DSC perfusion images of cerebral tumors with respect to i) the relative CBV (rCBV) calculated, ii) the cutoff value for discriminating low- and high-grade gliomas, and iii) the diagnostic performance for differentiating these tumors. Following approval of institutional review board, informed consent was obtained from all patients. Thirty-five patients with primary glioma (grade II, 9; grade III, 8; and grade IV, 18 patients) were included. DSC perfusion imaging was performed with 3-Tesla MRI scanner. CBV maps were generated by using 11 different algorithms of four commercially available software and one academic program. rCBV of each tumor compared to normal white matter was calculated by ROI measurements. Differences in rCBV value were compared between algorithms for each tumor grade. Receiver operator characteristics analysis was conducted for the evaluation of diagnostic performance of different algorithms for differentiating between different grades. Several algorithms showed significant differences in rCBV, especially for grade IV tumors. When differentiating between low- (II) and high-grade (III/IV) tumors, the area under the ROC curve (Az) was similar (range 0.85-0.87), and there were no significant differences in Az between any pair of algorithms. In contrast, the optimal cutoff values varied between algorithms (range 4.18-6.53). rCBV values of tumor and cutoff values for discriminating low- and high-grade gliomas differed between software packages, suggesting that optimal software-specific cutoff values should be used for diagnosis of high-grade gliomas.

  18. Review: magnetic resonance imaging of male/female differences in human adolescent brain anatomy

    Directory of Open Access Journals (Sweden)

    Giedd Jay N

    2012-08-01

    Full Text Available Abstract Improvements in neuroimaging technologies, and greater access to their use, have generated a plethora of data regarding male/female differences in the developing brain. Examination of these differences may shed light on the pathophysiology of the many illnesses that differ between the sexes and ultimately lead to more effective interventions. In this review, we attempt to synthesize the anatomic magnetic resonance imaging (MRI literature of male/female brain differences with emphasis on studies encompassing adolescence – a time of divergence in physical and behavioral characteristics. Across all ages total brain size is consistently reported to be about 10% larger in males. Structures commonly reported to be different between sexes include the caudate nucleus, amygdala, hippocampus, and cerebellum – all noted to have a relatively high density of sex steroid receptors. The direction and magnitude of reported brain differences depends on the methodology of data acquisition and analysis, whether and how the subcomponents are adjusted for the total brain volume difference, and the age of the participants in the studies. Longitudinal studies indicate regional cortical gray matter volumes follow inverted U shaped developmental trajectories with peak size occurring one to three years earlier in females. Cortical gray matter differences are modulated by androgen receptor genotyope and by circulating levels of hormones. White matter volumes increase throughout childhood and adolescence in both sexes but more rapidly in adolescent males resulting in an expanding magnitude of sex differences from childhood to adulthood.

  19. Archiver ailleurs, archiver autrement ? Archiving Elsewhere, Archiving Differently? : The Arab Image Foundation

    Directory of Open Access Journals (Sweden)

    Stefanie Baumann

    2012-05-01

    Full Text Available La « Fondation arabe pour l’image » est un projet archivistique dont le siège est à Beyrouth, et qui est dédié à la collection de photographies du Moyen-Orient prises par des photographes arabes entre 1860 et 1960. Elle a été lancée par un groupe d’artistes en vue d’instaurer une sorte d’histoire alternative de la photographie — qui contrerait les manuels d’histoire de la photographie européens ou américains dans lesquels les représentations photographiques du monde arabe sont souvent construites à partir d’un point de vue orientaliste. La structure et le fonctionnement de ce centre d’archives suivent des logiques hétérogènes remettant en question non seulement le concept d’archive et ses pratiques institutionnelles, mais aussi l’image photographique dans différents contextes, et selon ses différentes propriétés et connotations.The “Arab Image Foundation” is an archival project based in Beirut, dedicated to collecting photographs of the Middle East taken by Arab photographers between 1860 and 1960. It was founded by a group of artists who wanted to establish a kind of alternative history of photography—which would counter European and American textbooks on the history of photography, in which photographic representations of the Arab world are often constructed from an orientalist point of view. The structure and operation of this archive centre follow heterogeneous rationales, calling into question not only the concept of archives and their institutional practices, but also that of the photographic image in different contexts, and according to its different properties and connotations.

  20. Recognition of children on age-different images: Facial morphology and age-stable features.

    Science.gov (United States)

    Caplova, Zuzana; Compassi, Valentina; Giancola, Silvio; Gibelli, Daniele M; Obertová, Zuzana; Poppa, Pasquale; Sala, Remo; Sforza, Chiarella; Cattaneo, Cristina

    2017-07-01

    The situation of missing children is one of the most emotional social issues worldwide. The search for and identification of missing children is often hampered, among others, by the fact that the facial morphology of long-term missing children changes as they grow. Nowadays, the wide coverage by surveillance systems potentially provides image material for comparisons with images of missing children that may facilitate identification. The aim of study was to identify whether facial features are stable in time and can be utilized for facial recognition by comparing facial images of children at different ages as well as to test the possible use of moles in recognition. The study was divided into two phases (1) morphological classification of facial features using an Anthropological Atlas; (2) algorithm developed in MATLAB® R2014b for assessing the use of moles as age-stable features. The assessment of facial features by Anthropological Atlases showed high mismatch percentages among observers. On average, the mismatch percentages were lower for features describing shape than for those describing size. The nose tip cleft and the chin dimple showed the best agreement between observers regarding both categorization and stability over time. Using the position of moles as a reference point for recognition of the same person on age-different images seems to be a useful method in terms of objectivity and it can be concluded that moles represent age-stable facial features that may be considered for preliminary recognition. Copyright © 2017 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.

  1. Sex differences in memory of emotional images: a behavioral and electrophysiological investigation.

    Science.gov (United States)

    Glaser, Emma; Mendrek, Adrianna; Germain, Martine; Lakis, Nadia; Lavoie, Marc E

    2012-07-01

    Current research suggests that emotional responses differ between men and women. Sex differences regarding emotional effects on memory have been recently studied through brain imaging techniques. However, the majority of investigations have often neglected to balance the variable of emotional intensity (arousal) across pleasant and unpleasant pictures. Additionally, men and women were often mixed or studied separately. The current study aims at comparing men and women's electrophysiological responses related to emotional memory of photographic material. These responses were measured using Event Related brain Potentials (ERP) in response to a task of episodic memory of emotional images. The frontal N200, the parietal P300 and the central LPC were compared in 17 men and 17 women matched for age, social economic status, education and intelligence. Behavioral results showed that, in men, reaction times were modulated by valence, whereas for women, reaction times were mainly modulated by arousal. Accuracy was affected by both emotional valence and arousal, but only in women. ERP analyses revealed that emotional valence influenced earlier time components (frontal N200 and parietal P300), whereas arousal influenced memory in the later time component (central LPC). Moreover, sex differences, mediated by valence and arousal, were found in ERP responses at different times in the processing stream. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Pain profiling of patients with temporomandibular joint arthralgia and osteoarthritis diagnosed with different imaging techniques.

    Science.gov (United States)

    Kothari, Simple Futarmal; Baad-Hansen, Lene; Hansen, Lars Bolvig; Bang, Niels; Sørensen, Leif Hovgaard; Eskildsen, Helle Wulf; Svensson, Peter

    2016-12-01

    Clinical differentiation between pain mechanisms of temporomandibular joint (TMJ) arthralgia and osteoarthritis (OA) is challenging. The aims were to compare somatosensory function at the TMJs and conditioned pain modulation (CPM) effects between TMJ arthralgia and OA patients diagnosed clinically and based on different imaging techniques and age- and gender-matched healthy controls (n = 41). Patients (n = 58) underwent standard clinical examination and three different TMJ imaging modalities. After each examination, they were classified into arthralgia or OA based on the findings. TMJ region somatosensory testing was performed in all participants. Z-scores were calculated for patients based on healthy reference data. CPM was tested by comparing pressure pain thresholds (PPTs) at TMJ and thenar (control) before, during and after the application of painful and nonpainful cold stimuli. Data were analyzed using analyses of variance. Somatosensory abnormalities were commonly detected in both patient groups. Assessment of somatosensory function at the TMJ revealed that arthralgia patients were less sensitive to warmth, cold and tactile stimuli than OA patients (P painful cold application in all groups (P Pain profiles including somatosensory function differed between TMJ arthralgia and OA patients although CPM effects were similar in patients and controls. Thus, different TMJ pain conditions may share common pain mechanisms but the present study for the first time also indicated that differential pain mechanisms could be involved.

  3. Intensity of prolactinoma on T2-weighted magnetic resonance imaging: towards another gender difference

    Energy Technology Data Exchange (ETDEWEB)

    Kreutz, Julie [University Hospital Sart-Tilman, Department of Radiology, Liege (Belgium); Centre Hospitalier Universitaire de Liege, Domaine Universitaire du Sart Tilman, Service d' Imagerie Medicale, Liege (Belgium); Vroonen, Laurent; Petrossians, Patrick; Rostomyan, Liliya; Beckers, Albert [University Hospital Sart-Tilman, Department of Endocrinology, Liege (Belgium); Cattin, Francoise [University Hospital Besancon, Department of Radiology, Besancon (France); Thiry, Albert [University Hospital Sart-Tilman, Department of Pathology, Liege (Belgium); Tshibanda, Luaba [University Hospital Sart-Tilman, Department of Radiology, Liege (Belgium); Bonneville, Jean-Francois [University Hospital Sart-Tilman, Department of Radiology, Liege (Belgium); University Hospital Sart-Tilman, Department of Endocrinology, Liege (Belgium)

    2015-07-15

    Clinical presentations of prolactinomas are quite different between genders. In comparison with women's prolactinoma, those in men showed predominance of large tumors with high prolactin (PRL) levels. This preponderance could be attributed to a greater proliferative potential of the tumors. Differences in magnetic resonance imaging (MRI) signal at diagnosis have not been yet clearly evaluated. We conduct a retrospective study comparing MRI signal intensity (SI) on T2-weighted images (T2-WI) between 41 men and 41 women to investigate whether or not men prolactinoma present specific features. In addition to the size of the adenoma and PRL levels (P < 0001), prolactinomas in men also exhibit differences from those in women in signal on T2-WI on MRI (P < 0001). Women's prolactinomas are mostly of high SI on T2-WI while men's prolactinomas exhibit a more heterogeneous pattern of SI on T2-WI. Prolactinomas presenting with low SI on T2-WI are almost exclusively encountered in men. Presence of T2-WI hypointensities in pituitary adenoma can be predictive of a different subtype of prolactinoma almost encountered in men and possibly translate the presence of spherical amyloid deposits, in agreement with the literature. (orig.)

  4. Solfatara volcano subsurface imaging: two different approaches to process and interpret multi-variate data sets

    Science.gov (United States)

    Bernardinetti, Stefano; Bruno, Pier Paolo; Lavoué, François; Gresse, Marceau; Vandemeulebrouck, Jean; Revil, André

    2017-04-01

    The need to reduce model uncertainty and produce a more reliable geophysical imaging and interpretations is nowadays a fundamental task required to geophysics techniques applied in complex environments such as Solfatara Volcano. The use of independent geophysical methods allows to obtain many information on the subsurface due to the different sensitivities of the data towards parameters such as compressional and shearing wave velocities, bulk electrical conductivity, or density. The joint processing of these multiple physical properties can lead to a very detailed characterization of the subsurface and therefore enhance our imaging and our interpretation. In this work, we develop two different processing approaches based on reflection seismology and seismic P-wave tomography on one hand, and electrical data acquired over the same line, on the other hand. From these data, we obtain an image-guided electrical resistivity tomography and a post processing integration of tomographic results. The image-guided electrical resistivity tomography is obtained by regularizing the inversion of the electrical data with structural constraints extracted from a migrated seismic section using image processing tools. This approach enables to focus the reconstruction of electrical resistivity anomalies along the features visible in the seismic section, and acts as a guide for interpretation in terms of subsurface structures and processes. To integrate co-registrated P-wave velocity and electrical resistivity values, we apply a data mining tool, the k-means algorithm, to individuate relationships between the two set of variables. This algorithm permits to individuate different clusters with the objective to minimize the sum of squared Euclidean distances within each cluster and maximize it between clusters for the multivariate data set. We obtain a partitioning of the multivariate data set in a finite number of well-correlated clusters, representative of the optimum clustering of our

  5. Functional magnetic resonance imaging of the human cervical spinal cord with stimulation of different sensory dermatomes.

    Science.gov (United States)

    Stroman, P W; Krause, V; Malisza, K L; Frankenstein, U N; Tomanek, B

    2002-01-01

    Functional MR imaging (fMRI) of the cervical spinal cord was carried out in 13 healthy volunteers. A cold stimulus was applied, at different times, to three different sensory dermatome regions overlying the right hand and forearm: the thumb side of the palm, the little finger side of the palm, and the forearm below the elbow. Stimulation of these areas is expected to involve the 6(th), 8(th), and 5(th) cervical spinal cord segments respectively. Whereas true activations are expected to correspond to the region being stimulated, false activations such as arising from noise and motion, are not. The results demonstrate that clustering of active pixels into groups based on their intensity time courses discriminates false activations from true activations. Following clustering, the distribution of activity observed with fMRI matched the expected regions of neuronal activation with the different areas of stimulation on the hand and forearm.

  6. Single-vesicle imaging reveals different transport mechanisms between glutamatergic and GABAergic vesicles.

    Science.gov (United States)

    Farsi, Zohreh; Preobraschenski, Julia; van den Bogaart, Geert; Riedel, Dietmar; Jahn, Reinhard; Woehler, Andrew

    2016-02-26

    Synaptic transmission is mediated by the release of neurotransmitters, which involves exo-endocytotic cycling of synaptic vesicles. To maintain synaptic function, synaptic vesicles are refilled with thousands of neurotransmitter molecules within seconds after endocytosis, using the energy provided by an electrochemical proton gradient. However, it is unclear how transmitter molecules carrying different net charges can be efficiently sequestered while maintaining charge neutrality and osmotic balance. We used single-vesicle imaging to monitor pH and electrical gradients and directly showed different uptake mechanisms for glutamate and γ-aminobutyric acid (GABA) operating in parallel. In contrast to glutamate, GABA was exchanged for protons, with no other ions participating in the transport cycle. Thus, only a few components are needed to guarantee reliable vesicle filling with different neurotransmitters. Copyright © 2016, American Association for the Advancement of Science.

  7. Difference between healthy children and ADHD based on wavelet spectral analysis of nuclear magnetic resonance images

    Energy Technology Data Exchange (ETDEWEB)

    González Gómez Dulce, I., E-mail: isabeldgg@hotmail.com, E-mail: emoreno@fcfm.buap.mx, E-mail: mim@fcfm.buap.mx, E-mail: joserm84@gmail.com; Moreno Barbosa, E., E-mail: isabeldgg@hotmail.com, E-mail: emoreno@fcfm.buap.mx, E-mail: mim@fcfm.buap.mx, E-mail: joserm84@gmail.com; Hernández, Mario Iván Martínez, E-mail: isabeldgg@hotmail.com, E-mail: emoreno@fcfm.buap.mx, E-mail: mim@fcfm.buap.mx, E-mail: joserm84@gmail.com; Méndez, José Ramos, E-mail: isabeldgg@hotmail.com, E-mail: emoreno@fcfm.buap.mx, E-mail: mim@fcfm.buap.mx, E-mail: joserm84@gmail.com [Faculty of Physics and Mathematics, BUAP, Puebla, Pue. (Mexico); Silvia, Hidalgo Tobón [Hospital Infantil de México, Federico Gómez, Mexico DF. Mexico and Physics Department, Universidad Autónoma Metropolitana. Iztapalapa, Mexico DF. (Mexico); Pilar, Dies Suarez, E-mail: pilydies@yahoo.com, E-mail: neurodoc@prodigy.net.mx; Eduardo, Barragán Pérez, E-mail: pilydies@yahoo.com, E-mail: neurodoc@prodigy.net.mx [Hospital Infantil de México, Federico Gómez, Mexico DF. (Mexico); Benito, De Celis Alonso, E-mail: benileon@yahoo.com [Faculty of Physics and Mathematics, BUAP, Puebla, Pue. Mexico and Fundación para el Desarrollo Carlos Sigüenza. Puebla, Pue (Mexico)

    2014-11-07

    The main goal of this project was to create a computer algorithm based on wavelet analysis of region of homogeneity images obtained during resting state studies. Ideally it would automatically diagnose ADHD. Because the cerebellum is an area known to be affected by ADHD, this study specifically analysed this region. Male right handed volunteers (infants with ages between 7 and 11 years old) were studied and compared with age matched controls. Statistical differences between the values of the absolute integrated wavelet spectrum were found and showed significant differences (p<0.0015) between groups. This difference might help in the future to distinguish healthy from ADHD patients and therefore diagnose ADHD. Even if results were statistically significant, the small size of the sample limits the applicability of this methods as it is presented here, and further work with larger samples and using freely available datasets must be done.

  8. Deep learning for segmentation of brain tumors: can we train with images from different institutions?

    Science.gov (United States)

    Paredes, David; Saha, Ashirbani; Mazurowski, Maciej A.

    2017-03-01

    Deep learning and convolutional neural networks (CNNs) in particular are increasingly popular tools for segmentation and classification of medical images. CNNs were shown to be successful for segmentation of brain tumors into multiple regions or labels. However, in the environment which fosters data-sharing and collection of multi-institutional datasets, a question arises: does training with data from another institution with potentially different imaging equipment, contrast protocol, and patient population impact the segmentation performance of the CNN? Our study presents preliminary data towards answering this question. Specifically, we used MRI data of glioblastoma (GBM) patients for two institutions present in The Cancer Imaging Archive. We performed a process of training and testing CNN multiple times such that half of the time the CNN was tested on data from the same institution that was used for training and half of the time it was tested on another institution, keeping the training and testing set size constant. We observed a decrease in performance as measured by Dice coefficient when the CNN was trained with data from a different institution as compared to training with data from the same institution. The changes in performance for the entire tumor and for four different labels within the tumor were: 0.72 to 0.65 (p=0.06), 0.61 to 0.58 (p=0.49), 0.54 to 0.51 (p=0.82), 0.31 to 0.24 (p<0.03), and 0.43 to 0.31(p<0.003) respectively. In summary, we found that while data across institutions can be used for development of CNNs, this might be associated with a decrease in performance.

  9. Evaluation of different fitness functions integrated with genetic algorithm on unsupervised classification of satellite images

    Science.gov (United States)

    Yang, Y. F.; Yang, M. D.; Tsai, T. Y.

    2006-09-01

    In traditional unsupervised classification method, the number of clusters usually needs to be assigned subjectively by analysts, but in fact, in most situations, the prior knowledge of the research subject is difficult to acquire, so the suitable and best cluster numbers are very difficult to define. Therefore, in this research, an effective heuristic unsupervised classification method-Genetic Algorithm (GA) is introduced and tested here, because it can be through the mathematical model and calculating procedure of optimization to determine the best cluster numbers and centers automatically. Furthermore, two well-known models--Davies-Bouldin's and the K-Means algorithm, which adopted by most research for the applications in pattern classification, are integrated with GA as the fitness functions. In a word, in this research, a heuristic method-Genetic Algorithm (GA), is adopted and integrated with two different indices as the fitness functions to automatically interpret the clusters of satellite images for unsupervised classification. The classification results were compared to conventional ISODATA results, and to ground truth information derived from a topographic map for the estimation of classification accuracy. All image-processing program is developed in MATLAB, and the GA unsupervised classifier is tested on several image examples.

  10. Accurate computation of quaternion polar complex exponential transform for color images in different coordinate systems

    Science.gov (United States)

    Hosny, Khalid M.; Darwish, Mohamed M.

    2017-03-01

    Quaternion polar complex exponential transform (QPCET) moments and their invariants are widely used as powerful tools in many image processing and pattern recognition applications. However, the accuracy of the conventional approximated method for computing QPCET moments suffers from geometric and numerical errors. This approximated method is very time-consuming. Moreover, computing the high orders of approximated QPCET moments suffers from numerical instability. Computational methods are proposed for fast and accurate computation of the QPCET moments for color images in two coordinate systems. In the first method, the Gaussian quadrature method is applied to compute higher-order moments of QPCET in the Cartesian coordinates. On the other side, an exact kernel-based method is employed to compute the higher-order moments of QPCET in the polar coordinates. A set of numerical experiments is conducted and the obtained results clearly show that the conventional approximated method is unstable, where the numerical instability encountered with moment order ≥10, while the first proposed method is unstable for moment order ≥60. On the other side, the second proposed method is stable for all orders. The comparison clearly shows the superiority of the second proposed method in terms of image reconstruction capability, numerical stability, fast computation, rotation invariances, and robustness to different kinds of noises.

  11. How to Find More Supernovae with Less Work: Object ClassificationTechniques for Difference Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, Stephen; Aragon, Cecilia; Romano, Raquel; Thomas, RollinC.; Weaver, Benjamin A.; Wong, Daniel

    2007-05-02

    We present the results of applying new object classificationtechniques to difference images in the context of the Nearby SupernovaFactory supernova search. Most current supernova searches subtractreference images from new images, identify objects in these differenceimages, and apply simple threshold cuts on parameters such as statisticalsignificance, shape, and motionto reject objects such as cosmic rays,asteroids, and subtraction artifacts. Although most static objectssubtract cleanly, even a very low false positive detection rate can leadto hundreds of non-supernova candidates which must be vetted by humaninspection before triggering additional followup. In comparison to simplethreshold cuts, more sophisticated methods such as Boosted DecisionTrees, Random Forests, and Support Vector Machines provide dramaticallybetter object discrimination. At the Nearby Supernova Factory, we reducedthe number of non-supernova candidates by a factor of 10 while increasingour supernova identification efficiency. Methods such as these will becrucial for maintaining a reasonable false positive rate in the automatedtransient alert pipelines of upcoming projects such as PanSTARRS andLSST.

  12. Quantifying Plant Colour and Colour Difference as Perceived by Humans Using Digital Images

    Science.gov (United States)

    Kendal, Dave; Hauser, Cindy E.; Garrard, Georgia E.; Jellinek, Sacha; Giljohann, Katherine M.; Moore, Joslin L.

    2013-01-01

    Human perception of plant leaf and flower colour can influence species management. Colour and colour contrast may influence the detectability of invasive or rare species during surveys. Quantitative, repeatable measures of plant colour are required for comparison across studies and generalisation across species. We present a standard method for measuring plant leaf and flower colour traits using images taken with digital cameras. We demonstrate the method by quantifying the colour of and colour difference between the flowers of eleven grassland species near Falls Creek, Australia, as part of an invasive species detection experiment. The reliability of the method was tested by measuring the leaf colour of five residential garden shrub species in Ballarat, Australia using five different types of digital camera. Flowers and leaves had overlapping but distinct colour distributions. Calculated colour differences corresponded well with qualitative comparisons. Estimates of proportional cover of yellow flowers identified using colour measurements correlated well with estimates obtained by measuring and counting individual flowers. Digital SLR and mirrorless cameras were superior to phone cameras and point-and-shoot cameras for producing reliable measurements, particularly under variable lighting conditions. The analysis of digital images taken with digital cameras is a practicable method for quantifying plant flower and leaf colour in the field or lab. Quantitative, repeatable measurements allow for comparisons between species and generalisations across species and studies. This allows plant colour to be related to human perception and preferences and, ultimately, species management. PMID:23977275

  13. 3-D registration on carotid artery imaging data: MRI for different timesteps.

    Science.gov (United States)

    Bizopoulos, Paschalis A; Sakellarios, Antonis; Michalis, Lampros K; Koutsouris, Dimitrios D; Fotiadis, Dimitrios I

    2016-08-01

    A common problem which is faced by the researchers when dealing with arterial carotid imaging data is the registration of the geometrical structures between different imaging modalities or different timesteps. The use of the "Patient Position" DICOM field is not adequate to achieve accurate results due to the fact that the carotid artery is a relatively small structure and even imperceptible changes in patient position and/or direction make it difficult. While there is a wide range of simple/advanced registration techniques in the literature, there is a considerable number of studies which address the geometrical structure of the carotid artery without using any registration technique. On the other hand the existence of various registration techniques prohibits an objective comparison of the results using different registration techniques. In this paper we present a method for estimating the statistical significance that the choice of the registration technique has on the carotid geometry. One-Way Analysis of Variance (ANOVA) showed that the p-values were <;0.0001 for the distances of the lumen from the centerline for both right and left carotids of the patient case that was studied.

  14. Quantifying plant colour and colour difference as perceived by humans using digital images.

    Science.gov (United States)

    Kendal, Dave; Hauser, Cindy E; Garrard, Georgia E; Jellinek, Sacha; Giljohann, Katherine M; Moore, Joslin L

    2013-01-01

    Human perception of plant leaf and flower colour can influence species management. Colour and colour contrast may influence the detectability of invasive or rare species during surveys. Quantitative, repeatable measures of plant colour are required for comparison across studies and generalisation across species. We present a standard method for measuring plant leaf and flower colour traits using images taken with digital cameras. We demonstrate the method by quantifying the colour of and colour difference between the flowers of eleven grassland species near Falls Creek, Australia, as part of an invasive species detection experiment. The reliability of the method was tested by measuring the leaf colour of five residential garden shrub species in Ballarat, Australia using five different types of digital camera. Flowers and leaves had overlapping but distinct colour distributions. Calculated colour differences corresponded well with qualitative comparisons. Estimates of proportional cover of yellow flowers identified using colour measurements correlated well with estimates obtained by measuring and counting individual flowers. Digital SLR and mirrorless cameras were superior to phone cameras and point-and-shoot cameras for producing reliable measurements, particularly under variable lighting conditions. The analysis of digital images taken with digital cameras is a practicable method for quantifying plant flower and leaf colour in the field or lab. Quantitative, repeatable measurements allow for comparisons between species and generalisations across species and studies. This allows plant colour to be related to human perception and preferences and, ultimately, species management.

  15. Different modes of dynamic image analysis in monitoring of pharmaceutical dry milling process.

    Science.gov (United States)

    Nalluri, Venkateshwar Rao; Schirg, Peter; Gao, Xin; Virdis, Antoine; Imanidis, Georgios; Kuentz, Martin

    2010-05-31

    This article focuses on the process analytical technology (PAT) of pharmaceutical dry milling. The first objective is to compare different modes of dynamic image analysis namely, on-line, in-line and at-line for monitoring powder milling. The second objective is to introduce time evolving size and shape analysis (TESSA). Thus, a conical mill was equipped with a dynamic image analysis system which consisted of a xenon flash light and charge-coupled device (CCD) camera. Different pharmaceutical excipients and granulates were chosen as models. The results from the on-line, in-line and the at-line measurement modes showed similar size distributions for the various materials studied, however differences were observed that were mainly attributed to sampling and dispersion. A high correlation of 0.975 (pprocess. This monitoring approach of particle size and shape has potential to reduce product variability, facilitates process development, and ultimately helps in establishing quality by design concept for the manufacture of solid dosage forms. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  16. Switching circuit to improve the frequency modulation difference-intensity THz quantum cascade laser imaging

    Energy Technology Data Exchange (ETDEWEB)

    Saat, N. K. [Department of Physics, Faculty of Science, University Putra Malaysia (Malaysia); Dean, P.; Khanna, S. P.; Salih, M.; Linfield, E. H.; Davies, A. G. [School of Electronic and Electrical Engineering, University of Leeds, Woodhouse Lane, Leeds LS2 9JT (United Kingdom)

    2015-04-24

    We demonstrate new switching circuit for difference-intensity THz quantum cascade laser (QCL) imaging by amplitude modulation and lock in detection. The switching circuit is designed to improve the frequency modulation so that it can stably lock the amplitude modulation of the QCL and the detector output. The combination of a voltage divider and a buffer in switching circuit to quickly switch the amplitude of the QCL biases of 15.8 V and 17.2 V is successfully to increase the frequency modulation up to ∼100 Hz.

  17. A Weighted Difference of Anisotropic and Isotropic Total Variation for Relaxed Mumford-Shah Image Segmentation

    Science.gov (United States)

    2016-05-01

    boundaries between them. The values are designated by c1 and c2 and are obtained on the regions Σ and Σc respectively. The two regions and values are unknowns...model. For the remainder of the paper, we refer to L1−αL2 as the weighted difference of anisotropic and isotropic TV: Jani−αJiso = ‖ ux ‖1 + ‖uy‖1−α... ux |2 + |uy|2‖1 (3) where it is understood that these norms are operating on the gradients of the image. Here, α ∈ [0, 1] and is chosen based on

  18. Imaging With Synthesized 2D Mammography: Differences, Advantages, and Pitfalls Compared With Digital Mammography.

    Science.gov (United States)

    Zuckerman, Samantha P; Maidment, Andrew D A; Weinstein, Susan P; McDonald, Elizabeth S; Conant, Emily F

    2017-07-01

    Synthesized 2D (s2D) mammography is rapidly replacing digital mammography in breast imaging with digital breast tomosynthesis (DBT) to reduce radiation dose and maintain screening outcomes. We illustrate variations in the appearance of s2D and digital mammograms to aid in implementation of this technology. Despite subjective differences in the appearance of s2D and digital mammograms, early outcomes of screening using s2D mammography and DBT are not inferior to those achieved with digital mammography and DBT. Understanding these variations may aid in implementing this technique and improving patient outcomes.

  19. Conspicuity of breast lesions at different b values on diffusion-weighted imaging

    Directory of Open Access Journals (Sweden)

    Chen Xin

    2012-08-01

    Full Text Available Abstract Background Diffusion-weighted (DW imaging has shown potential to differentiate between malignant and benign breast lesions. However, different b values have been used with varied sensitivity and specificity. This study aims to prospectively evaluate the influence of b value on the detection and assessment of breast lesions. Methods Institutional review board approval and informed patient consent were obtained. Between February 2010 and September 2010, sixty women suspected of having breast cancer by clinical examination and mammography underwent bilateral breast MRI and DW imaging (with maximum b values of 600, 800, and 1000 s/mm2. Conspicuity grades of lesions at different b values on DW images were performed. Signal intensity and apparent diffusion coefficient (ADC values were recorded and compared among different b values by the signal-to-noise ratio (SNR, contrast-to-noise ratio (CNR and receiver operating characteristic (ROC curve. Results Fifty-seven lesions from 52 recruited patients including 39/57 (68% malignant and 18/57 (32% benign were confirmed with pathology. DCE MRI accurately detected 53 lesions with the sensitivity of 93.0% and specificity of 66.7%, and DW imaging accurately detected 51 lesions with the sensitivity of 89.5% and specificity of 100%. There were no significant differences in conspicuity grades compared among the three b values (P = 0.072, although the SNR and CNR of breast lesions decreased significantly with higher b values. Mean ADCs of malignant lesions (b = 600 s/mm2, 1.07 ± 0.26 × 10-3 mm2/s; b = 800 s/mm2, 0.96 ± 0.22 × 10-3 mm2/s; b = 1000 s/mm2, 0.92 ± 0.26 × 10-3 mm2/s were significantly lower than those of benign lesions (b = 600 s/mm2, 1.55 ± 0.40 × 10-3 mm2/s; b = 800 s/mm2, 1.43 ± 0.38 × 10-3 mm2/s; b = 1000 s/mm2, 1.49 ± 0.38 × 10-3 mm2/s with all P values P = 0.303 and 0

  20. The Performance Evaluation of Multi-Image 3d Reconstruction Software with Different Sensors

    Science.gov (United States)

    Mousavi, V.; Khosravi, M.; Ahmadi, M.; Noori, N.; Naveh, A. Hosseini; Varshosaz, M.

    2015-12-01

    Today, multi-image 3D reconstruction is an active research field and generating three dimensional model of the objects is one the most discussed issues in Photogrammetry and Computer Vision that can be accomplished using range-based or image-based methods. Very accurate and dense point clouds generated by range-based methods such as structured light systems and laser scanners has introduced them as reliable tools in the industry. Image-based 3D digitization methodologies offer the option of reconstructing an object by a set of unordered images that depict it from different viewpoints. As their hardware requirements are narrowed down to a digital camera and a computer system, they compose an attractive 3D digitization approach, consequently, although range-based methods are generally very accurate, image-based methods are low-cost and can be easily used by non-professional users. One of the factors affecting the accuracy of the obtained model in image-based methods is the software and algorithm used to generate three dimensional model. These algorithms are provided in the form of commercial software, open source and web-based services. Another important factor in the accuracy of the obtained model is the type of sensor used. Due to availability of mobile sensors to the public, popularity of professional sensors and the advent of stereo sensors, a comparison of these three sensors plays an effective role in evaluating and finding the optimized method to generate three-dimensional models. Lots of research has been accomplished to identify a suitable software and algorithm to achieve an accurate and complete model, however little attention is paid to the type of sensors used and its effects on the quality of the final model. The purpose of this paper is deliberation and the introduction of an appropriate combination of a sensor and software to provide a complete model with the highest accuracy. To do this, different software, used in previous studies, were compared and

  1. Potential Evaluation of Different Types of Images and Their Combination for the Classification of GIS Objects Cropland and Grassland

    Science.gov (United States)

    Recio, J. A.; Helmholz, P.; Müller, S.

    2011-09-01

    In many publications the performance of different classification algorithms regarding to agricultural classes is evaluated. In contrast, this paper focuses on the potential of different imagery for the classification of the two most frequent classes: cropland and grassland. For our experiments three categories of imagery, high resolution aerial images, high resolution RapidEye satellite images and medium resolution Disaster Monitoring Constellation (DMC) satellite images are examined. An object-based image classification, as one of the most reliable methods for the automatic updating and evaluation of landuse geospatial databases, is chosen. The object boundaries are taken from a GIS database, each object is described by means of a set of image based features. Spectral, textural and structural (semivariogram derived) features are extracted from images of different dates and sensors. During classification a supervised decision trees generating algorithm is applied. To evaluate the potential of the different images, all possible combinations of the available image data are tested during classification. The results show that the best performance of landuse classification is based on RapidEye data (overall accuracy of 90%), obtaining slightly accuracy increases when this imagery is combined with additional image data (overall accuracy of 92%).

  2. POTENTIAL EVALUATION OF DIFFERENT TYPES OF IMAGES AND THEIR COMBINATION FOR THE CLASSIFICATION OF GIS OBJECTS CROPLAND AND GRASSLAND

    Directory of Open Access Journals (Sweden)

    J. A. Recio

    2012-09-01

    Full Text Available In many publications the performance of different classification algorithms regarding to agricultural classes is evaluated. In contrast, this paper focuses on the potential of different imagery for the classification of the two most frequent classes: cropland and grassland. For our experiments three categories of imagery, high resolution aerial images, high resolution RapidEye satellite images and medium resolution Disaster Monitoring Constellation (DMC satellite images are examined. An object-based image classification, as one of the most reliable methods for the automatic updating and evaluation of landuse geospatial databases, is chosen. The object boundaries are taken from a GIS database, each object is described by means of a set of image based features. Spectral, textural and structural (semivariogram derived features are extracted from images of different dates and sensors. During classification a supervised decision trees generating algorithm is applied. To evaluate the potential of the different images, all possible combinations of the available image data are tested during classification. The results show that the best performance of landuse classification is based on RapidEye data (overall accuracy of 90%, obtaining slightly accuracy increases when this imagery is combined with additional image data (overall accuracy of 92%.

  3. Dosimetry analysis of panoramic-imaging devices in different-sized phantoms.

    Science.gov (United States)

    Wahid, Muizz A; Choi, Ella; MacDonald, David S; Ford, Nancy L

    2017-03-01

    The aim of this study is to measure the radiographic dose in adult, adolescent, and child head-sized PMMA phantoms for three panoramic-imaging devices: the panoramic mode on two CBCT machines (Carestream 9300 and i-CAT NG) and the Planmeca ProMax 2D. A SEDENTEXCT dose index adult phantom and custom-built adolescent and pediatric PMMA dosimetry phantoms were used. Panoramic radiographs were performed using a Planmeca ProMax 2D and the panoramic mode on a Carestream 9300 CBCT and an i-CAT NG using the protocols used clinically. Point dose measurements were performed at the center, around the periphery and on the surface of each phantom using a thimble ionization chamber. Five repeat measurements were taken at each location. For each machine, single-factor ANOVA was conducted to determine dose differences between protocols in each phantom, as well as determine the differences in absorbed dose when the same protocol was used for different-sized phantoms. For any individual phantom, using protocols with lower kVp, mA, or acquisition times resulted in statistically significant dose savings, as expected. When the same protocol was used for different-sized phantoms, the smaller phantom had a higher radiation dose due to less attenuation of x-rays by the smaller phantom and differences in the positioning of the ion chamber relative to the focal trough. The panoramic-mode on the CBCT machines produce images suitable for clinical use with similar dose levels to the stand-alone panoramic device. Significant dose savings may result by selecting age- and size- appropriate protocols for pediatric patients, but a wider range of protocols for children and adolescents may be beneficial. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  4. Evaluation of different scintillators for 1MV NDE x-ray imaging

    Science.gov (United States)

    Zentai, George; Ganguly, Arundhuti; Visrshup, Gary

    2014-03-01

    X-ray radiography is an important and frequently used NDE method of testing metal structures, such as tube welding quality, cracks and voids in cast iron or other metals. It gives fast and visible answer for structural defects. The Varian high energy portal imagers on Clinacs used in cancer treatment were tested for this purpose. We compared the traditional Gadox (LANEX) screen with and without a 1mm Cu buildup plate as used clinically. We also tested different hybrid scintillators, which consisted of different phosphor layers deposited onto fiberoptic plates. The last screen tested was a 2cm thick fiberoptic plate which contained scintillating fibers. The sensitivity (ADU = number of digital counts per a given X-ray dose), the resolution (MTF - modulation transfer function) and the DQE (detective quantum efficiency) were compared, with a 1 MV source, for these X-ray conversion screens. We found that the additional 1mm Cu plate, which improves the absorption and the contrast at 6 or higher energy MeV imaging, does not improve the image quality at 1MV. Rather it attenuates the X-rays, resulting in lower sensitivity and a lower DQE(0) of 2.2% with the additional Cu plate compared to DQE(0) of ~4% without the Cu plate. The hybrid scintillators with evaporated phosphors on fiberoptic plates tested were too thin resulting in low sensitivity. The best results were obtained from the thick scintillating fiberoptic screens, which provided the best DQE and high resolution with the 1MV X-ray beam. Further optimization is planned by changing the thickness of the scintillating fiber optic plate.

  5. A novel weighted total difference based image reconstruction algorithm for few-view computed tomography.

    Directory of Open Access Journals (Sweden)

    Wei Yu

    Full Text Available In practical applications of computed tomography (CT imaging, due to the risk of high radiation dose imposed on the patients, it is desired that high quality CT images can be accurately reconstructed from limited projection data. While with limited projections, the images reconstructed often suffer severe artifacts and the edges of the objects are blurred. In recent years, the compressed sensing based reconstruction algorithm has attracted major attention for CT reconstruction from a limited number of projections. In this paper, to eliminate the streak artifacts and preserve the edge structure information of the object, we present a novel iterative reconstruction algorithm based on weighted total difference (WTD minimization, and demonstrate the superior performance of this algorithm. The WTD measure enforces both the sparsity and the directional continuity in the gradient domain, while the conventional total difference (TD measure simply enforces the gradient sparsity horizontally and vertically. To solve our WTD-based few-view CT reconstruction model, we use the soft-threshold filtering approach. Numerical experiments are performed to validate the efficiency and the feasibility of our algorithm. For a typical slice of FORBILD head phantom, using 40 projections in the experiments, our algorithm outperforms the TD-based algorithm with more than 60% gains in terms of the root-mean-square error (RMSE, normalized root mean square distance (NRMSD and normalized mean absolute distance (NMAD measures and with more than 10% gains in terms of the peak signal-to-noise ratio (PSNR measure. While for the experiments of noisy projections, our algorithm outperforms the TD-based algorithm with more than 15% gains in terms of the RMSE, NRMSD and NMAD measures and with more than 4% gains in terms of the PSNR measure. The experimental results indicate that our algorithm achieves better performance in terms of suppressing streak artifacts and preserving the edge

  6. Estimation of chlorophyll-a concentration of different seasons in outdoor ponds using hyperspectral imaging.

    Science.gov (United States)

    Wang, Lu; Pu, Hongbin; Sun, Da-Wen

    2016-01-15

    Chlorophyll a (Chl-a) is regarded as one of the important components to estimate water quality and sustainability of freshwater aquaculture operations. In the current study, a hyperspectral imaging (HSI) system was used to determine the effect of season models on the accuracy of Chl-a estimation in outdoor aquaculture ponds. A visible and near infrared hyperspectral imaging system (400-1000nm) was used to measure surface spectral reflectance (R) of water collected from outdoor ponds in four different seasons. Firstly, values of surface spectral reflectance (R) were amplified by a baseline correction (740nm). Two-band, three-band and four-band spectral reflectance were used to compute Chl-a concentration and a new cross band ratio algorithm with six wavelengths was proposed in the study. Results indicated that two-band model established based on reflectance ratio (R702/R666) had better performances for Chl-a prediction with determination coefficients (r(2)) of 0.908 than those by (R675(-1)-R691(-1))*R743 and (R675(-1)-R691(-1))/(R743(-1)-R691(-1)) models with r(2) of 0.902 and 0.896, respectively. Six optimal wavelengths (410, 682, 691, 966, 972, and 997) were identified using successive projections algorithm (SPA). The optimized regression model (R410(-1)-R966(-1))/(R682(-1)-R972(-1))/(R691(-1)-R997(-1)) showed best result with r(2) of 0.961 for Chl-a prediction. Model of cross band ratio algorithm with six wavelengths was mapped to each pixel in the image to display Chl-a component in outdoor ponds under four different seasons. The current study showed that it was feasible to use the HSI system for monitoring the influence of seasons for outdoor aquaculture water quality. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Local texture descriptors for the assessment of differences in diffusion magnetic resonance imaging of the brain.

    Science.gov (United States)

    Thomsen, Felix Sebastian Leo; Delrieux, Claudio Augusto; de Luis-García, Rodrigo

    2017-03-01

    Descriptors extracted from magnetic resonance imaging (MRI) of the brain can be employed to locate and characterize a wide range of pathologies. Scalar measures are typically derived within a single-voxel unit, but neighborhood-based texture measures can also be applied. In this work, we propose a new set of descriptors to compute local texture characteristics from scalar measures of diffusion tensor imaging (DTI), such as mean and radial diffusivity, and fractional anisotropy. We employ weighted rotational invariant local operators, namely standard deviation, inter-quartile range, coefficient of variation, quartile coefficient of variation and skewness. Sensitivity and specificity of those texture descriptors were analyzed with tract-based spatial statistics of the white matter on a diffusion MRI group study of elderly healthy controls, patients with mild cognitive impairment (MCI), and mild or moderate Alzheimer's disease (AD). In addition, robustness against noise has been assessed with a realistic diffusion-weighted imaging phantom and the contamination of the local neighborhood with gray matter has been measured. The new texture operators showed an increased ability for finding formerly undetected differences between groups compared to conventional DTI methods. In particular, the coefficient of variation, quartile coefficient of variation, standard deviation and inter-quartile range of the mean and radial diffusivity detected significant differences even between previously not significantly discernible groups, such as MCI versus moderate AD and mild versus moderate AD. The analysis provided evidence of low contamination of the local neighborhood with gray matter and high robustness against noise. The local operators applied here enhance the identification and localization of areas of the brain where cognitive impairment takes place and thus indicate them as promising extensions in diffusion MRI group studies.

  8. Land use mapping from CBERS-2 images with open source tools by applying different classification algorithms

    Science.gov (United States)

    Sanhouse-García, Antonio J.; Rangel-Peraza, Jesús Gabriel; Bustos-Terrones, Yaneth; García-Ferrer, Alfonso; Mesas-Carrascosa, Francisco J.

    2016-02-01

    Land cover classification is often based on different characteristics between their classes, but with great homogeneity within each one of them. This cover is obtained through field work or by mean of processing satellite images. Field work involves high costs; therefore, digital image processing techniques have become an important alternative to perform this task. However, in some developing countries and particularly in Casacoima municipality in Venezuela, there is a lack of geographic information systems due to the lack of updated information and high costs in software license acquisition. This research proposes a low cost methodology to develop thematic mapping of local land use and types of coverage in areas with scarce resources. Thematic mapping was developed from CBERS-2 images and spatial information available on the network using open source tools. The supervised classification method per pixel and per region was applied using different classification algorithms and comparing them among themselves. Classification method per pixel was based on Maxver algorithms (maximum likelihood) and Euclidean distance (minimum distance), while per region classification was based on the Bhattacharya algorithm. Satisfactory results were obtained from per region classification, where overall reliability of 83.93% and kappa index of 0.81% were observed. Maxver algorithm showed a reliability value of 73.36% and kappa index 0.69%, while Euclidean distance obtained values of 67.17% and 0.61% for reliability and kappa index, respectively. It was demonstrated that the proposed methodology was very useful in cartographic processing and updating, which in turn serve as a support to develop management plans and land management. Hence, open source tools showed to be an economically viable alternative not only for forestry organizations, but for the general public, allowing them to develop projects in economically depressed and/or environmentally threatened areas.

  9. Comparing the performance of different ultrasonic images enhancement for speckle noise reduction in ultrasound images using techniques: a preference study

    Science.gov (United States)

    Rana, Md. Shohel; Sarker, Kaushik; Bhuiyan, Touhid; Hassan, Md. Maruf

    2017-06-01

    Diagnostic ultrasound (US) is an important tool in today's sophisticated medical diagnostics. Nearly every medical discipline benefits itself from this relatively inexpensive method that provides a view of the inner organs of the human body without exposing the patient to any harmful radiations. Medical diagnostic images are usually corrupted by noise during their acquisition and most of the noise is speckle noise. To solve this problem, instead of using adaptive filters which are widely used, No-Local Means based filters have been used to de-noise the images. Ultrasound images of four organs such as Abdomen, Ortho, Liver, Kidney, Brest and Prostrate of a Human body have been used and applied comparative analysis study to find out the output. These images were taken from Siemens SONOLINE G60 S System and the output was compared by matrices like SNR, RMSE, PSNR IMGQ and SSIM. The significance and compared results were shown in a tabular format.

  10. Land Surface Temperature from Landsat 5 TM images: comparison of different methods using airborne thermal data

    Directory of Open Access Journals (Sweden)

    M. B. Giannini

    2015-10-01

    Full Text Available In this study, several methods to compute land surface temperatures (LST from Landsat TM5 data are compared. Two different approaches are considered. An image based approach that takes into account atmospherically corrected data by using a dark object subtraction model (DOS-1 and computes the emissivity as NDVI function. The emissivity of a surface is controlled by such factors as water content, chemical composition, structure and roughness; it can be determined as the contribution of the different components that belong to the pixels according to their proportions. NDVI method takes into account that vegetation and soils are the main surface cover for the terrestrial component. This emissivity is used to compute the LST by the inversion of Planck function. The other approach applies atmospheric correction to thermal infrared band and considers a constant emissivity of 0.95. Furthermore, the land surface temperature is computed by hybrid methods that result from the merger of the two initially considered approaches. These results are compared with the surface temperature measured by airborne Multispectral Infrared and Visible Imaging Spectrometer (MIVIS. The LST measured by MIVIS sensor can be considered closer to the real surface temperature because the data are acquired at an altitude of 1500 m and are not affected by significant atmospheric effects such as for satellite data, acquired at 705 km from the Earth’s surface. The best results are obtained by considering variable emissivity.

  11. Optimising MR perfusion imaging: comparison of different software-based approaches in acute ischaemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Schaafs, Lars-Arne [Charite-Universitaetsmedizin, Department of Radiology, Berlin (Germany); Charite-Universitaetsmedizin, Academic Neuroradiology, Department of Neurology and Center for Stroke Research, Berlin (Germany); Porter, David [Fraunhofer Institute for Medical Image Computing MEVIS, Bremen (Germany); Audebert, Heinrich J. [Charite-Universitaetsmedizin, Department of Neurology with Experimental Neurology, Berlin (Germany); Fiebach, Jochen B.; Villringer, Kersten [Charite-Universitaetsmedizin, Academic Neuroradiology, Department of Neurology and Center for Stroke Research, Berlin (Germany)

    2016-11-15

    Perfusion imaging (PI) is susceptible to confounding factors such as motion artefacts as well as delay and dispersion (D/D). We evaluate the influence of different post-processing algorithms on hypoperfusion assessment in PI analysis software packages to improve the clinical accuracy of stroke PI. Fifty patients with acute ischaemic stroke underwent MRI imaging in the first 24 h after onset. Diverging approaches to motion and D/D correction were applied. The calculated MTT and CBF perfusion maps were assessed by volumetry of lesions and tested for agreement with a standard approach and with the final lesion volume (FLV) on day 6 in patients with persisting vessel occlusion. MTT map lesion volumes were significantly smaller throughout the software packages with correction of motion and D/D when compared to the commonly used approach with no correction (p = 0.001-0.022). Volumes on CBF maps did not differ significantly (p = 0.207-0.925). All packages with advanced post-processing algorithms showed a high level of agreement with FLV (ICC = 0.704-0.879). Correction of D/D had a significant influence on estimated lesion volumes and leads to significantly smaller lesion volumes on MTT maps. This may improve patient selection. (orig.)

  12. Image Segmentation Based on Constrained Spectral Variance Difference and Edge Penalty

    Directory of Open Access Journals (Sweden)

    Bo Chen

    2015-05-01

    Full Text Available Segmentation, which is usually the first step in object-based image analysis (OBIA, greatly influences the quality of final OBIA results. In many existing multi-scale segmentation algorithms, a common problem is that under-segmentation and over-segmentation always coexist at any scale. To address this issue, we propose a new method that integrates the newly developed constrained spectral variance difference (CSVD and the edge penalty (EP. First, initial segments are produced by a fast scan. Second, the generated segments are merged via a global mutual best-fitting strategy using the CSVD and EP as merging criteria. Finally, very small objects are merged with their nearest neighbors to eliminate the remaining noise. A series of experiments based on three sets of remote sensing images, each with different spatial resolutions, were conducted to evaluate the effectiveness of the proposed method. Both visual and quantitative assessments were performed, and the results show that large objects were better preserved as integral entities while small objects were also still effectively delineated. The results were also found to be superior to those from eCongnition’s multi-scale segmentation.

  13. Characterization of sildenafil citrate tablets of different sources by near infrared chemical imaging and chemometric tools.

    Science.gov (United States)

    Sabin, Guilherme P; Lozano, Valeria A; Rocha, Werickson F C; Romão, Wanderson; Ortiz, Rafael S; Poppi, Ronei J

    2013-11-01

    The chemical imaging technique by near infrared spectroscopy was applied for characterization of formulations in tablets of sildenafil citrate of six different sources. Five formulations were provided by Brazilian Federal Police and correspond to several trademarks of prohibited marketing and one was an authentic sample of Viagra. In a first step of the study, multivariate curve resolution was properly chosen for the estimation of the distribution map of concentration of the active ingredient in tablets of different sources, where the chemical composition of all excipients constituents was not truly known. In such cases, it is very difficult to establish an appropriate calibration technique, so that only the information of sildenafil is considered independently of the excipients. This determination was possible only by reaching the second-order advantage, where the analyte quantification can be performed in the presence of unknown interferences. In a second step, the normalized histograms of images from active ingredient were grouped according to their similarities by hierarchical cluster analysis. Finally it was possible to recognize the patterns of distribution maps of concentration of sildenafil citrate, distinguishing the true formulation of Viagra. This concept can be used to improve the knowledge of industrial products and processes, as well as, for characterization of counterfeit drugs. Copyright © 2013. Published by Elsevier B.V.

  14. Difference between healthy children and ADHD based on wavelet spectral analysis of nuclear magnetic resonance images

    Science.gov (United States)

    González Gómez, Dulce I.; Moreno Barbosa, E.; Martínez Hernández, Mario Iván; Ramos Méndez, José; Hidalgo Tobón, Silvia; Dies Suarez, Pilar; Barragán Pérez, Eduardo; De Celis Alonso, Benito

    2014-11-01

    The main goal of this project was to create a computer algorithm based on wavelet analysis of region of homogeneity images obtained during resting state studies. Ideally it would automatically diagnose ADHD. Because the cerebellum is an area known to be affected by ADHD, this study specifically analysed this region. Male right handed volunteers (infants with ages between 7 and 11 years old) were studied and compared with age matched controls. Statistical differences between the values of the absolute integrated wavelet spectrum were found and showed significant differences (pADHD patients and therefore diagnose ADHD. Even if results were statistically significant, the small size of the sample limits the applicability of this methods as it is presented here, and further work with larger samples and using freely available datasets must be done.

  15. Stochastic rank correlation: a robust merit function for 2D/3D registration of image data obtained at different energies.

    Science.gov (United States)

    Birkfellner, Wolfgang; Stock, Markus; Figl, Michael; Gendrin, Christelle; Hummel, Johann; Dong, Shuo; Kettenbach, Joachim; Georg, Dietmar; Bergmann, Helmar

    2009-08-01

    In this article, the authors evaluate a merit function for 2D/3D registration called stochastic rank correlation (SRC). SRC is characterized by the fact that differences in image intensity do not influence the registration result; it therefore combines the numerical advantages of cross correlation (CC)-type merit functions with the flexibility of mutual-information-type merit functions. The basic idea is that registration is achieved on a random subset of the image, which allows for an efficient computation of Spearman's rank correlation coefficient. This measure is, by nature, invariant to monotonic intensity transforms in the images under comparison, which renders it an ideal solution for intramodal images acquired at different energy levels as encountered in intrafractional kV imaging in image-guided radiotherapy. Initial evaluation was undertaken using a 2D/3D registration reference image dataset of a cadaver spine. Even with no radiometric calibration, SRC shows a significant improvement in robustness and stability compared to CC. Pattern intensity, another merit function that was evaluated for comparison, gave rather poor results due to its limited convergence range. The time required for SRC with 5% image content compares well to the other merit functions; increasing the image content does not significantly influence the algorithm accuracy. The authors conclude that SRC is a promising measure for 2D/3D registration in IGRT and image-guided therapy in general.

  16. Digital images segmentation: a state of art of the different methods ...

    African Journals Online (AJOL)

    An image is a planar representation of a scene or a 3 D object. The primary information associated to each point of the image is transcribed in grey level or in colour. Image analysis is the set of methods which permits the extraction of pertinent information from the image according to the concerned application, to treat them ...

  17. Detection of pulmonary embolism using 64-slice multidetector-row computed tomography: accuracy and reproducibility on different image reconstruction parameters

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jung Im; Ahn, Myeong Im; Park, Seog Hee (Dept. of Radiology, Seoul St Mary' s Hospital, College of Medicine, The Catholic Univ. of Korea (Korea, Republic of)), email: jijung@catholic.ac.kr; Kim, Ki Jun (Deparment of Radiology, Incheon St Mary' s Hospital, College of Medicine, The Catholic Univ. of Korea (Korea, Republic of)); Kim, Hyo Rim (Deparment of Radiology, Yeouido St Mary' s Hospital, College of Medicine, The Catholic Univ. of Korea (Korea, Republic of)); Park, Hyun Jin (Dept. of Radiology, St Vincent Hospital, College of Medicine, The Catholic Univ. of Korea (Korea, Republic of)); Jung, SeungHee; Lim, Hyeon Woo (Deparment of Preventive Medicine, College of Medicine, The Catholic Univ. of Korea (Korea, Republic of))

    2011-05-15

    Background Direct comparison of different image reconstruction parameters to detect pulmonary embolism (PE) using 64-slice multidetector-row computed tomography (MDCT) is absent and the most accurate image reconstruction parameters have not yet been proven. Purpose To compare different image reconstruction parameters for detecting PE using 64-slice MDCT in patients suspected of having an acute PE. Material and Methods Forty patients who underwent pulmonary CT angiography with 64-slice MDCT for a suspected PE were included. Different image reconstruction parameters were used for each patient: axial and coronal images with slice thicknesses of 0.625 mm, 1.3 mm, and 2.5 mm and axial maximum intensity projection (MIP) images with slab thicknesses of 1.3 mm, 2.5 mm, and 5 mm. Four experienced radiologists reviewed the images. The diagnosis of a PE was based on consensus review of axial 0.625 mm slice thickness images by two chest radiologists with allowing multiplanar reconstruction. Accuracy and reproducibility (kappa value) were evaluated. Results In 15 of 40 patients, a PE was diagnosed. For detecting lobar PEs, axial images with a slice thickness of 1.25 mm and all coronal re-formatted images showed comparable results to axial images with a slice thickness of 0.625 mm. For detecting segmental PEs, axial images with a slice thickness of 1.25 mm and coronal images with a slice thickness of 0.625 mm re-formatted images showed comparable results to axial images of a slice thickness of 0.625 mm. For detecting subsegmental PEs, axial images with a slice thickness of 0.625 mm showed the highest sensitivity. Better reproducibility was obtained when the thinner slice thickness reconstructions were in axial and coronal images. However, reproducibility of MIP images with slab thicknesses of 2.5 mm and 5 mm was similar for detecting segmental and subsegmental PEs. Conclusion Thin-slice reconstruction of less than 1 mm is mandatory for visualization of PE at the subsegmental

  18. Perceived body image and weight: discrepancies and gender differences among University undergraduates.

    Science.gov (United States)

    Maruf, F A; Akinpelu, A O; Nwankwo, M J

    2012-12-01

    Body image (BI) is a multidimensional construct that includes perceptual, attitudinal, behavioural components, and feedback from other people's perception of oneself. The feedback from others and the degree to which one accepts or rejects it can determine self evaluation and perception. Body weight perception is a strong determinant of nutritional habits and weight management among adolescents. One of the barriers to reducing rise in obesity prevalence could be its cultural acceptability in some developing countries. To explore the gender influences on perception of self- and opposite-sex body images (BI), perceived body weight and the actual body weight categories at which discrepancies occur among the perceived BIs in undergraduates. This was a survey of perceptual dimension of BI, perceived body weight and actual body weight carried out in 121 undergraduates aged 21-29 years. Discrepancies occurred between self-perceived BI and each of actual body weight (p= 0.00 at 0.00-0.02 confidence interval (CI)), perceived body weight (p= 0.01 at 0.000-0.02 CI) and self-ideal BI (p= 0.03 at 0.000-0.05 CI) of normal-weight males. Self-perceived BI and perceived body weight also differed in normal-weight females (p= 0.02 at 0.000-0.04 CI). Discrepancies (p= 0.02 at 0.00-0.04 CI) occurred between self-perceived BI and self-ideal BI, and between self-perceived BI and desired BI (p= 0.02 at 0.00-0.04 CI) in overweight females. Gender differences occurred for self-ideal BI (p= 0.00 at 0.00-0.02 CI), ideal image for the opposite sex (IBIOS) (p= 0.02 at 0.00-0.04 CI) and desired BI (p= 0.00 at 0.00-0.02 CI). Normal-weight males perceived their BI differently from their actual body weight, perceived body weight and self-ideal BI whereas normal-weight females perceived their BI differently from only their perceived body weight. Discrepancies occur between self-ideal BI and self-perceived BI, and between self-perceived BI and desired BI in overweight females. There are differential

  19. Gender Differences in Peer and Parental Influences: Body Image Disturbance, Self-Worth, and Psychological Functioning in Preadolescent Children.

    Science.gov (United States)

    Phares, Vicky; Steinberg, Ari R.; Thompson, J. Kevin

    2004-01-01

    The connections between body image disturbance and psychological functioning have been well established in samples of older adolescent girls and young women. Little is known, however, about body image in younger children. In particular, little is known about possible gender differences in preadolescent children. The current study explored…

  20. Restoration of Medical Images with Different Types of Noise; Restauracion de Imagenes Medicas con Diferentes Tipos de Ruido

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, M. G.; Vidal, V.; Verdu, G.; Mayo, P.; Rodenas, F.

    2013-07-01

    In this paper, a method is proposed to reduce the Gaussian, speckle and impulsive noise. This filter, named PGMFDNL filter combines a nonlinear diffusion and fuzzy peer group. The proposed filter can effectively reduce image noise without any information about the noise present in the image. As a result, the proposed method obtains good performance in different types of noise.

  1. Gender differences in contrast-enhanced magnetic resonance imaging after acute myocardial infarction.

    Science.gov (United States)

    Langhans, Birgit; Ibrahim, Tareq; Hausleiter, Jörg; Sonne, Carolin; Martinoff, Stefan; Schömig, Albert; Hadamitzky, Martin

    2013-03-01

    Besides different risk profiles for cardiovascular events in men and women, several studies reported gender differences in mortality after acute myocardial infarction (AMI). As infarct size has been shown to correlate with mortality, it is widely accepted as surrogate marker for clinical outcome. Currently, cardiovascular imaging studies covering the issue of gender differences are rare. As magnetic resonance scar characterization parameters are emerging as additional prognostic factors after acute myocardial infarction, we sought to evaluate gender differences in CMR infarct characteristics in patients after acute myocardial infarction. We prospectively analyzed patients (n = 448) with AMI and primary angioplasty, who underwent contrast-enhanced cardiac magnetic resonance (CMR) imaging on a 1.5 T scanner in median 5 [4, 6] days after the acute event. [corrected]. CMR scar size was measured 15 min after gadolinium injection. In addition presence and extent of microvascular obstruction (MVO) was assessed. A matched pair analysis was performed in order to exclude confounding by gender related co-morbidities and gender differences in established clinical risk factors. Matching process according to clinical risk defined by GRACE score resulted in 93 mixed gender couples. Women were significantly older than men (64.4 ± 11.9 vs. 60.5 ± 12.3, p = 0.03) and presented with a significantly better ejection fraction before angioplasty (48.9 ± 8.4 vs. 46.2 ± 8.9, p = 0.04). Infarct size did not differ significantly between women and men (13.5 ± 10.7 vs. 15.1 ± 11.8, p = 0.32). Size of MVO was significantly smaller in women than in men (0.48 ± 1.3 vs. 1.2 ± 3.0, p = 0.03). Comparing scar characterization between women and men with similar risk profiles revealed no gender differences in scar size. Size of MVO, however, was significantly smaller in women and might reflect better cardioprotective mechanisms in women. Whether these changes have prognostic implications has to

  2. Evaluation of different methods for measuring lateral tibial slope using magnetic resonance imaging.

    Science.gov (United States)

    Lipps, David B; Wilson, Annie M; Ashton-Miller, James A; Wojtys, Edward M

    2012-12-01

    Since lateral tibial slope (LTS) affects the amount of anterior tibial translation and anterior cruciate ligament (ACL) strain during a dynamic maneuver, accurate measurements of LTS may be beneficial in screening people at a higher risk for ACL injury. Methods for measuring LTS on magnetic resonance imaging (MRI) scans of the proximal tibia include the midpoint and circle methods. No current studies have validated different LTS measurement methods using a proximal tibia MRI scan. We tested the null hypotheses that (1) LTS measurements were independent of the length of tibia imaged using the midpoint method, and (2) LTS measurements calculated from different methods (midpoint, circle, and full tibia) would not differ significantly. Controlled laboratory study. Blinded observers measured LTS from 3-tesla, 3-dimensional MRIs from 40 size-matched donors according to 1 circle method and 3 midpoint methods. Outcomes were then compared with the full-tibial anatomic axis (line connecting the center of 2 circles fit within the proximal and distal tibia) in 11 donors. Bonferroni-corrected paired t tests (significance, P methods. The circle and full-tibia methods had the lowest interobserver and intraobserver variability, whereas the midpoint method with 10-cm tibia was the most variable. The midpoint method with 10-cm and 15-cm proximal tibia closely resembled LTS measurements with the full-tibial anatomic axis. The circle method, although repeatable, provided smaller numerical LTS measurements than the full-tibia and midpoint methods. Although LTS measurements using the midpoint method can resemble measurements made using the full tibia, the reliability of the midpoint method depends on the length of proximal tibia used. The circle method may be the preferred method for future studies since it was the most repeatable method and is independent of proximal tibial length. LTS measurements vary depending on the method used.

  3. Super-resolution imaging reveals distinct chromatin folding for different epigenetic states.

    Science.gov (United States)

    Boettiger, Alistair N; Bintu, Bogdan; Moffitt, Jeffrey R; Wang, Siyuan; Beliveau, Brian J; Fudenberg, Geoffrey; Imakaev, Maxim; Mirny, Leonid A; Wu, Chao-ting; Zhuang, Xiaowei

    2016-01-21

    Metazoan genomes are spatially organized at multiple scales, from packaging of DNA around individual nucleosomes to segregation of whole chromosomes into distinct territories. At the intermediate scale of kilobases to megabases, which encompasses the sizes of genes, gene clusters and regulatory domains, the three-dimensional (3D) organization of DNA is implicated in multiple gene regulatory mechanisms, but understanding this organization remains a challenge. At this scale, the genome is partitioned into domains of different epigenetic states that are essential for regulating gene expression. Here we investigate the 3D organization of chromatin in different epigenetic states using super-resolution imaging. We classified genomic domains in Drosophila cells into transcriptionally active, inactive or Polycomb-repressed states, and observed distinct chromatin organizations for each state. All three types of chromatin domains exhibit power-law scaling between their physical sizes in 3D and their domain lengths, but each type has a distinct scaling exponent. Polycomb-repressed domains show the densest packing and most intriguing chromatin folding behaviour, in which chromatin packing density increases with domain length. Distinct from the self-similar organization displayed by transcriptionally active and inactive chromatin, the Polycomb-repressed domains are characterized by a high degree of chromatin intermixing within the domain. Moreover, compared to inactive domains, Polycomb-repressed domains spatially exclude neighbouring active chromatin to a much stronger degree. Computational modelling and knockdown experiments suggest that reversible chromatin interactions mediated by Polycomb-group proteins play an important role in these unique packaging properties of the repressed chromatin. Taken together, our super-resolution images reveal distinct chromatin packaging for different epigenetic states at the kilobase-to-megabase scale, a length scale that is directly

  4. Computational imaging reveals shape differences between normal and malignant prostates on MRI

    Science.gov (United States)

    Rusu, Mirabela; Purysko, Andrei S.; Verma, Sadhna; Kiechle, Jonathan; Gollamudi, Jay; Ghose, Soumya; Herrmann, Karin; Gulani, Vikas; Paspulati, Raj; Ponsky, Lee; Böhm, Maret; Haynes, Anne-Maree; Moses, Daniel; Shnier, Ron; Delprado, Warick; Thompson, James; Stricker, Phillip; Madabhushi, Anant

    2017-01-01

    We seek to characterize differences in the shape of the prostate and the central gland (combined central and transitional zones) between men with biopsy confirmed prostate cancer and men who were identified as not having prostate cancer either on account of a negative biopsy or had pelvic imaging done for a non-prostate malignancy. T2w MRI from 70 men were acquired at three institutions. The cancer positive group (PCa+) comprised 35 biopsy positive (Bx+) subjects from three institutions (Gleason scores: 6–9, Stage: T1–T3). The negative group (PCa−) combined 24 biopsy negative (Bx−) from two institutions and 11 subjects diagnosed with rectal cancer but with no clinical or MRI indications of prostate cancer (Cl−). The boundaries of the prostate and central gland were delineated on T2w MRI by two expert raters and were used to construct statistical shape atlases for the PCa+, Bx− and Cl− prostates. An atlas comparison was performed via per-voxel statistical tests to localize shape differences (significance assessed at p hypertrophy in the Bx− subpopulation, resulting in significant volume and posterior side shape differences relative to PCa+ group. Significant differences in the corresponding prostate shapes were noted at the apex when comparing the Cl− and PCa+ prostates. PMID:28145532

  5. Respiration impacts phase difference-based field maps in echo planar imaging.

    Science.gov (United States)

    Zeller, Mario; Kraus, Philip; Müller, Alexander; Bley, Thorsten A; Köstler, Herbert

    2014-08-01

    To investigate the influence of respiration on field maps for geometric distortion correction derived from two rapidly acquired consecutive echo planar images. Displacement maps of the brains of seven healthy volunteers were acquired under breath hold and free breathing for a 64 × 64 pixel image matrix using phase labeling for additional coordinate encoding (PLACE). The maps were transformed into undistorted gradient echo space and analyzed with regard to standard deviation and absolute deviation from an accurate reference field map derived from a multiecho reference scan. Standard deviations between PLACE field maps and absolute difference from the reference field map are a factor of about 3 higher under free breathing than under breath hold. The mean deviation decreases from 3 pixels in the slice closest to the lung to 1 pixel in the most superior slice under free breathing and from 1 to field map and thus corrupt the geometric distortion correction. The effect can be greatly reduced by acquiring the field map data under breath hold. Data acquired under free breathing can be improved with retrospective phase correction or by averaging several field maps. Copyright © 2013 Wiley Periodicals, Inc.

  6. Differences between time domain and Fourier domain optical coherence tomography in imaging tissues.

    Science.gov (United States)

    Gao, W; Wu, X

    2017-11-01

    It has been numerously demonstrated that both time domain and Fourier domain optical coherence tomography (OCT) can generate high-resolution depth-resolved images of living tissues and cells. In this work, we compare the common points and differences between two methods when the continuous and random properties of live tissue are taken into account. It is found that when relationships that exist between the scattered light and tissue structures are taken into account, spectral interference measurements in Fourier domain OCT (FDOCT) is more advantageous than interference fringe envelope measurements in time domain OCT (TDOCT) in the cases where continuous property of tissue is taken into account. It is also demonstrated that when random property of tissue is taken into account FDOCT measures the Fourier transform of the spatial correlation function of the refractive index and speckle phenomena will limit the effective limiting imaging resolution in both TDOCT and FDOCT. Finally, the effective limiting resolution of both TDOCT and FDOCT are given which can be used to estimate the effective limiting resolution in various practical applications. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  7. Quantitative assessment on coronary computed tomography angiography (CCTA) image quality: comparisons between genders and different tube voltage settings.

    Science.gov (United States)

    Chian, Teo Chee; Nassir, Norziana Mat; Ibrahim, Mohd Izuan; Yusof, Ahmad Khairuddin Md; Sabarudin, Akmal

    2017-02-01

    This study was carried out to quantify and compare the quantitative image quality of coronary computed tomography angiography (CCTA) between genders as well as between different tube voltages scan protocols. Fifty-five cases of CCTA were collected retrospectively and all images including reformatted axial images at systolic and diastolic phases as well as images with curved multi planar reformation (cMPR) were obtained. Quantitative image quality including signal intensity, image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of right coronary artery (RCA), left anterior descending artery (LAD), left circumflex artery (LCx) and left main artery (LM) were quantified using Analyze 12.0 software. Six hundred and fifty-seven coronary arteries were evaluated. There were no significant differences in any quantitative image quality parameters between genders. 100 kilovoltage peak (kVp) scanning protocol produced images with significantly higher signal intensity compared to 120 kVp scanning protocol (Pgenders and different tube voltages. Lower tube voltage (100 kVp) scanning protocol is recommended in clinical practice to reduce the radiation dose to patient.

  8. Satisfaction with Body Image for Early Adolescent Females: The Impact of Pubertal Timing within Different School Environments.

    Science.gov (United States)

    Blyth, Dale A.; And Others

    1985-01-01

    The impact of different school environments on the process of incorporating adolescent physical changes into body image is explored using data on 225 White females from a longitudinal study. (Author/LMO)

  9. Intensity-based dual model method for generation of synthetic CT images from standard T2-weighted MR images - Generalized technique for four different MR scanners.

    Science.gov (United States)

    Koivula, Lauri; Kapanen, Mika; Seppälä, Tiina; Collan, Juhani; Dowling, Jason A; Greer, Peter B; Gustafsson, Christian; Gunnlaugsson, Adalsteinn; Olsson, Lars E; Wee, Leonard; Korhonen, Juha

    2017-12-01

    Recent studies have shown that it is possible to conduct entire radiotherapy treatment planning (RTP) workflow using only MR images. This study aims to develop a generalized intensity-based method to generate synthetic CT (sCT) images from standard T2-weighted (T2 w ) MR images of the pelvis. This study developed a generalized dual model HU conversion method to convert standard T2 w MR image intensity values to synthetic HU values, separately inside and outside of atlas-segmented bone volume contour. The method was developed and evaluated with 20 and 35 prostate cancer patients, respectively. MR images with scanning sequences in clinical use were acquired with four different MR scanners of three vendors. For the generated synthetic CT (sCT) images of the 35 prostate patients, the mean (and maximal) HU differences in soft and bony tissue volumes were 16 ± 6 HUs (34 HUs) and -46 ± 56 HUs (181 HUs), respectively, against the true CT images. The average of the PTV mean dose difference in sCTs compared to those in true CTs was -0.6 ± 0.4% (-1.3%). The study provides a generalized method for sCT creation from standard T2 w images of the pelvis. The method produced clinically acceptable dose calculation results for all the included scanners and MR sequences. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Atomic force microscopy imaging of polyurethane nanoparticles onto different solid substrates

    Energy Technology Data Exchange (ETDEWEB)

    Beddin Fritzen-Garcia, Mauricia [Laboratorio de Bioenergetica e Bioquimica de Macromoleculas, Departamento de Ciencias Farmaceuticas, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); POLIMAT, Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)], E-mail: maurifritzen@hotmail.com; Giehl Zanetti-Ramos, Betina [Laboratorio de Bioenergetica e Bioquimica de Macromoleculas, Departamento de Ciencias Farmaceuticas, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Schweitzer de Oliveira, Cristian [Laboratorio de Filmes Finos e Superficies, Departamento de Fisica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Soldi, Valdir [POLIMAT, Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Avelino Pasa, Andre [Laboratorio de Filmes Finos e Superficies, Departamento de Fisica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Creczynski-Pasa, Tania Beatriz [Laboratorio de Bioenergetica e Bioquimica de Macromoleculas, Departamento de Ciencias Farmaceuticas, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)

    2009-03-01

    Atomic force microscopy (AFM) is a technique suited for characterizing nanoparticles on solid surfaces because it offers the capability of 3D visualization and quantitative information about the topography of the samples. In the present work, contact-mode AFM has been applied to imaging polyurethane nanoparticles formulated from a natural triol and isophorone diisocyanate (IPDI) in the presence of poly(ethylene glycol) (PEG). The colloidal polymeric system was deposited on mica, hydrophilic and hydrophobic silicon solid substrates to evaluate the size and shape of the nanoparticles. Our data showed that the nanoparticles were better distributed on mica and hydrophilic silicon. From the analysis of line-scan profiles we obtained different values for the ratio between the diameter and the height of the nanoparticles, indicating that the shape of the particles depends on the interaction between the nanoparticles and the substrate.

  11. Finite-Difference Time-Domain Simulation for Three-dimensional Polarized Light Imaging

    CERN Document Server

    Menzel, Miriam; De Raedt, Hans; Michielsen, Kristel

    2016-01-01

    Three-dimensional Polarized Light Imaging (3D-PLI) is a promising technique to reconstruct the nerve fiber architecture of human post-mortem brains from birefringence measurements of histological brain sections with micrometer resolution. To better understand how the reconstructed fiber orientations are related to the underlying fiber structure, numerical simulations are employed. Here, we present two complementary simulation approaches that reproduce the entire 3D-PLI analysis: First, we give a short review on a simulation approach that uses the Jones matrix calculus to model the birefringent myelin sheaths. Afterwards, we introduce a more sophisticated simulation tool: a 3D Maxwell solver based on a Finite-Difference Time-Domain algorithm that simulates the propagation of the electromagnetic light wave through the brain tissue. We demonstrate that the Maxwell solver is a valuable tool to better understand the interaction of polarized light with brain tissue and to enhance the accuracy of the fiber orientati...

  12. Pictorial essay of ultrasound-reconstructed coronal plane images of the uterus in different uterine pathologies.

    Science.gov (United States)

    Grigore, Mihaela; Grigore, Anamaria; Gafitanu, Dumitru; Furnica, Cristina

    2017-12-11

    Imaging in the major planes (horizontal, coronal, and sagittal) of the uterus is important for determining anatomy and allowing the findings to be standardized, and for evaluating and diagnosing different pathological conditions in clinical practice. Examination of the coronal plane is an important step in identifying uterine pathologies and their relationships to the endometrial canal. Three-dimensional (3D) ultrasound reveals the normal anatomy better and improves the depiction of abnormal anatomy, as the coronal plane of the uterus can easily be obtained using 3D reconstruction techniques. Our pictorial essay demonstrates that adding 3D ultrasound to a routine gynecological workup can be beneficial for clinicians, enabling a precise diagnosis to be made. In addition, the volumes obtained and stored by 3D ultrasound can allow students or residents to become more familiar with normal and abnormal pelvic structures. Clin. Anat, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  13. Catalytic activity in individual cracking catalyst particles imaged throughout different life stages by selective staining.

    Science.gov (United States)

    Buurmans, Inge L C; Ruiz-Martínez, Javier; Knowles, William V; van der Beek, David; Bergwerff, Jaap A; Vogt, Eelco T C; Weckhuysen, Bert M

    2011-09-18

    Fluid catalytic cracking (FCC) is the major conversion process used in oil refineries to produce valuable hydrocarbons from crude oil fractions. Because the demand for oil-based products is ever increasing, research has been ongoing to improve the performance of FCC catalyst particles, which are complex mixtures of zeolite and binder materials. Unfortunately, there is limited insight into the distribution and activity of individual zeolitic domains at different life stages. Here we introduce a staining method to visualize the structure of zeolite particulates and other FCC components. Brønsted acidity maps have been constructed at the single particle level from fluorescence microscopy images. By applying a statistical methodology to a series of catalysts deactivated via industrial protocols, a correlation is established between Brønsted acidity and cracking activity. The generally applicable method has clear potential for catalyst diagnostics, as it determines intra- and interparticle Brønsted acidity distributions for industrial FCC materials.

  14. Catalytic activity in individual cracking catalyst particles imaged throughout different life stages by selective staining

    Science.gov (United States)

    Buurmans, Inge L. C.; Ruiz-Martínez, Javier; Knowles, William V.; van der Beek, David; Bergwerff, Jaap A.; Vogt, Eelco T. C.; Weckhuysen, Bert M.

    2011-11-01

    Fluid catalytic cracking (FCC) is the major conversion process used in oil refineries to produce valuable hydrocarbons from crude oil fractions. Because the demand for oil-based products is ever increasing, research has been ongoing to improve the performance of FCC catalyst particles, which are complex mixtures of zeolite and binder materials. Unfortunately, there is limited insight into the distribution and activity of individual zeolitic domains at different life stages. Here we introduce a staining method to visualize the structure of zeolite particulates and other FCC components. Brønsted acidity maps have been constructed at the single particle level from fluorescence microscopy images. By applying a statistical methodology to a series of catalysts deactivated via industrial protocols, a correlation is established between Brønsted acidity and cracking activity. The generally applicable method has clear potential for catalyst diagnostics, as it determines intra- and interparticle Brønsted acidity distributions for industrial FCC materials.

  15. Rapid assessment of different oxygenic phototrophs and single-cell photosynthesis with multicolour variable chlorophyll fluorescence imaging

    DEFF Research Database (Denmark)

    Trampe, Erik Christian Løvbjerg; Kolbowski, J.; Schreiber, U.

    2011-01-01

    , red or white light. Automated sequential exposure of microscopic samples to the three excitation colours enables subsequent deconvolution of the resulting fluorescence signals and colour marking of cells with different photopigmentation, i.e., cyanobacteria, green algae, red algae and diatoms......We present a new system for microscopic multicolour variable chlorophyll fluorescence imaging of aquatic phototrophs. The system is compact and portable and enables microscopic imaging of photosynthetic performance of individual cells and chloroplasts using different combinations of blue, green...

  16. Body image drawings dissociate ethnic differences and anorexia in adolescent girls.

    Science.gov (United States)

    Goldzak-Kunik, Galit; Leshem, Micah

    2017-01-01

    To distinguish between ethnic differences among segregated schoolgirls and restrictive anorexia nervosa using a simple culture-fair test of body image (BI) figure drawings. Several responses to BI figure drawings by 178 adolescent schoolgirls from three ethnically distinct and segregated schools and communities in Israel, Jewish secular (JS), Jewish Haredi (H), and Christian Arab (C), and a group of 14 severely restricting anorexic girls (AN). BI evaluations were analyzed by MANCOVA, followed by paired or Student-t tests for comparisons between responses and groups respectively. Pearson r served for correlations and the Fisher Z for differences between slopes. Despite the total ethnic segregation among the schoolgirls, there are commonalities; all prefer a thinner ideal BI, and are similarly dissatisfied with their BI. However, ethnic differences also emerge: C underestimate their BI and how others view them, and H true and Ideal BI evaluations correlate, unlike the other groups. Despite this variability, and in stark contrast, the anorexic girls show a gross misperception of their BI, even in comparison to girls equated for BMI. The findings show that figure drawings evaluation of BI is a simple and robust instrument dissociating clinical and ethnic responses. Clinicians may consider body figure drawings as a simple, supportive, diagnostic for first-line recognition for risk of AN in adolescent girls.

  17. Body Image and Disordered Eating among Asian American and Caucasian College Students: An Examination of Race and Gender Differences.

    Science.gov (United States)

    Mintz, Laurie B.; Kashubeck, Susan

    1999-01-01

    Examined gender differences within race and race differences within gender regarding various body image and disordered eating variables among Caucasian and Asian American college students. Regardless of race, women reported more problem attitudes and behaviors than men. Gender differences were common and similar for both ethnic groups. Race made…

  18. Progressive gender differences of structural brain networks in healthy adults: a longitudinal, diffusion tensor imaging study.

    Directory of Open Access Journals (Sweden)

    Yu Sun

    Full Text Available Sexual dimorphism in the brain maturation during childhood and adolescence has been repeatedly documented, which may underlie the differences in behaviors and cognitive performance. However, our understanding of how gender modulates the development of structural connectome in healthy adults is still not entirely clear. Here we utilized graph theoretical analysis of longitudinal diffusion tensor imaging data over a five-year period to investigate the progressive gender differences of brain network topology. The brain networks of both genders showed prominent economical "small-world" architecture (high local clustering and short paths between nodes. Additional analysis revealed a more economical "small-world" architecture in females as well as a greater global efficiency in males regardless of scan time point. At the regional level, both increased and decreased efficiency were found across the cerebral cortex for both males and females, indicating a compensation mechanism of cortical network reorganization over time. Furthermore, we found that weighted clustering coefficient exhibited significant gender-time interactions, implying different development trends between males and females. Moreover, several specific brain regions (e.g., insula, superior temporal gyrus, cuneus, putamen, and parahippocampal gyrus exhibited different development trajectories between males and females. Our findings further prove the presence of sexual dimorphism in brain structures that may underlie gender differences in behavioral and cognitive functioning. The sex-specific progress trajectories in brain connectome revealed in this work provide an important foundation to delineate the gender related pathophysiological mechanisms in various neuropsychiatric disorders, which may potentially guide the development of sex-specific treatments for these devastating brain disorders.

  19. Progressive gender differences of structural brain networks in healthy adults: a longitudinal, diffusion tensor imaging study.

    Science.gov (United States)

    Sun, Yu; Lee, Renick; Chen, Yu; Collinson, Simon; Thakor, Nitish; Bezerianos, Anastasios; Sim, Kang

    2015-01-01

    Sexual dimorphism in the brain maturation during childhood and adolescence has been repeatedly documented, which may underlie the differences in behaviors and cognitive performance. However, our understanding of how gender modulates the development of structural connectome in healthy adults is still not entirely clear. Here we utilized graph theoretical analysis of longitudinal diffusion tensor imaging data over a five-year period to investigate the progressive gender differences of brain network topology. The brain networks of both genders showed prominent economical "small-world" architecture (high local clustering and short paths between nodes). Additional analysis revealed a more economical "small-world" architecture in females as well as a greater global efficiency in males regardless of scan time point. At the regional level, both increased and decreased efficiency were found across the cerebral cortex for both males and females, indicating a compensation mechanism of cortical network reorganization over time. Furthermore, we found that weighted clustering coefficient exhibited significant gender-time interactions, implying different development trends between males and females. Moreover, several specific brain regions (e.g., insula, superior temporal gyrus, cuneus, putamen, and parahippocampal gyrus) exhibited different development trajectories between males and females. Our findings further prove the presence of sexual dimorphism in brain structures that may underlie gender differences in behavioral and cognitive functioning. The sex-specific progress trajectories in brain connectome revealed in this work provide an important foundation to delineate the gender related pathophysiological mechanisms in various neuropsychiatric disorders, which may potentially guide the development of sex-specific treatments for these devastating brain disorders.

  20. Calibration of the visual difference predictor for estimating visibility of JPEG2000 compression artifacts in CT images

    Science.gov (United States)

    Kim, Kil Joong; Mantiuk, Rafal; Lee, Kyoung Ho; Heidrich, Wolfgang

    2010-02-01

    Many visual difference predictors (VDPs) have used basic psychophysical data (such as ModelFest) to calibrate the algorithm parameters and to validate their performances. However, the basic psychophysical data often do not contain sufficient number of stimuli and its variations to test more complex components of a VDP. In this paper we calibrate the Visual Difference Predictor for High Dynamic Range images (HDR-VDP) using radiologists' experimental data for JPEG2000 compressed CT images which contain complex structures. Then we validate the HDR-VDP in predicting the presence of perceptible compression artifacts. 240 CT-scan images were encoded and decoded using JPEG2000 compression at four compression ratios (CRs). Five radiologists participated to independently determine if each image pair (original and compressed images) was indistinguishable or distinguishable. A threshold CR for each image, at which 50% of radiologists would detect compression artifacts, was estimated by fitting a psychometric function. The CT images compressed at the threshold CRs were used to calibrate the HDR-VDP parameters and to validate its prediction accuracy. Our results showed that the HDR-VDP calibrated for the CT image data gave much better predictions than the HDR-VDP calibrated to the basic psychophysical data (ModelFest + contrast masking data for sine gratings).

  1. Two-dimensional vacuum ultraviolet images in different MHD events on the EAST tokamak

    Science.gov (United States)

    Zhijun, WANG; Xiang, GAO; Tingfeng, MING; Yumin, WANG; Fan, ZHOU; Feifei, LONG; Qing, ZHUANG; EAST Team

    2018-02-01

    A high-speed vacuum ultraviolet (VUV) imaging telescope system has been developed to measure the edge plasma emission (including the pedestal region) in the Experimental Advanced Superconducting Tokamak (EAST). The key optics of the high-speed VUV imaging system consists of three parts: an inverse Schwarzschild-type telescope, a micro-channel plate (MCP) and a visible imaging high-speed camera. The VUV imaging system has been operated routinely in the 2016 EAST experiment campaign. The dynamics of the two-dimensional (2D) images of magnetohydrodynamic (MHD) instabilities, such as edge localized modes (ELMs), tearing-like modes and disruptions, have been observed using this system. The related VUV images are presented in this paper, and it indicates the VUV imaging system is a potential tool which can be applied successfully in various plasma conditions.

  2. Dose optimization for different medical imaging tasks from exposure index, exposure control factor, and MAS in digital radiography.

    Science.gov (United States)

    Zhang, Menglong; Zhao, Bin; Wang, Yaying; Chen, Weixia; Hou, Lixia

    2012-09-01

    In radiographic examination, not all medical imaging tasks require the same level of image quality or diagnostic information. Criteria should be established for different imaging tasks to avoid excessive doses where there is no clear net benefit in the diagnosis or the image quality. An exposure index provided by manufacturers would be a useful tool for this purpose. This study aims to establish an optimum exposure index to be used as a guideline for clinical imaging tasks to minimize radiation exposure for chest digital radiography. A three-level classification of image quality (high, medium, and low) for chest imaging tasks was carried out. An anthropomorphic phantom was employed to establish minimum exposure index and exposure (mAs) for clinical imaging task type I (corresponding to high image quality). The exposures of medium and low quality images derived from it. Thirty patients were exposed consecutively with these optimized exposure factors, and clinical tasks were considered, while another 30 patients were exposed with the exposure factors routinely used in practice. Image quality was assessed objectively by a consensus panel. The optimized exposure provided a significant reduction of the mean exposure index from 1,556 to 1,207 (p < 0.0001) and mean patient's entrance surface dose from 0.168 mGy to 0.092 mGy (p < 0.0001). The results show that a clinical-task-determined radiographic procedure is more conducive to radiation protection of patients. In this study, the posteroanterior chest imaging examination was chosen as an example. This procedure can also apply to other body parts and views.

  3. Learner differences and learning outcomes in an introductory biochemistry class: attitude toward images, visual cognitive skills, and learning approach.

    Science.gov (United States)

    Milner, Rachel E

    2014-01-01

    The practice of using images in teaching is widespread, and in science education images are used so extensively that some have argued they are now the "main vehicle of communication" (C. Ferreira, A. Arroio Problems Educ. 21st Century 2009, 16, 48-53). Although this phenomenon is especially notable in the field of biochemistry, we know little about the role and importance of images in communicating concepts to students in the classroom. This study reports the development of a scale to assess students' attitude toward biochemical images, particularly their willingness and ability to use the images to support their learning. In addition, because it is argued that images are central in the communication of biochemical concepts, we investigated three "learner differences" which might impact learning outcomes in this kind of classroom environment: attitude toward images, visual cognitive skills, and learning approach. Overall, the students reported a positive attitude toward the images, the majority agreeing that they liked images and considered them useful. However, the participants also reported that verbal explanations were more important than images in helping them to understand the concepts. In keeping with this we found that there was no relationship between learning outcomes and the students' self-reported attitude toward images or visual cognitive skills. In contrast, learning outcomes were significantly correlated with the students' self-reported approach to learning. These findings suggest that images are not necessarily the main vehicle of communication in a biochemistry classroom and that verbal explanations and encouragement of a deep learning approach are important considerations in improving our pedagogical approach. © 2013 International Union of Biochemistry and Molecular Biology, Inc.

  4. Optimization of Split-Bolus CT Urography: Effect of Differences in Allocation of Contrast Medium and Prolongation of Imaging Delay.

    Science.gov (United States)

    Lee, Dahye; Cho, Eun-Suk; Kim, Joo Hee; Kim, Yong Pyo; Lee, Hyeon-Kyeong; Yu, Jeong-Sik; Chung, Jae-Joon

    2017-07-01

    The purpose of this study was to find the optimal allocation ratio of contrast medium (CM) in split-bolus CT urography (CTU) and to investigate the effect of increased imaging delays for synchronous nephrographic-excretory phase imaging. One hundred ninety-two patients were randomly assigned to one of three protocols with different allocation ratios of CM: group A, 30% of CM at first bolus and 70% of CM at second bolus; group B, 70% and 30%; or group C, 50% and 50%. Saline (250 mL) was administered after the first CM bolus. Patients were subdivided by different imaging delay times (8, 10, 12, and 14 minutes). The attenuation values of the renal cortex and medulla were measured, and the opacification and maximal caliber of each segment of the ureter were evaluated. Renal cortical enhancement was significantly higher in group A (mean ± SD, 145.9 ± 17.5 HU) than group B (120.6 ± 106.3 HU). No significant difference in renal parenchymal enhancement was found with increased imaging delay times. The opacification and maximal caliber of each ureter segment showed no significant difference with different allocation ratios of CM or increased imaging delay times. A split-bolus CTU protocol with a larger CM volume administered at the second injection and an 8-minute imaging delay was the optimal protocol with regard to opacification of the ureter, renal parenchymal enhancement, and shorter examination time.

  5. Different molecular signatures in magnetic resonance imaging-staged facioscapulohumeral muscular dystrophy muscles.

    Science.gov (United States)

    Tasca, Giorgio; Pescatori, Mario; Monforte, Mauro; Mirabella, Massimiliano; Iannaccone, Elisabetta; Frusciante, Roberto; Cubeddu, Tiziana; Laschena, Francesco; Ottaviani, Pierfrancesco; Ricci, Enzo

    2012-01-01

    Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common muscular dystrophies and is characterized by a non-conventional genetic mechanism activated by pathogenic D4Z4 repeat contractions. By muscle Magnetic Resonance Imaging (MRI) we observed that T2-short tau inversion recovery (T2-STIR) sequences identify two different conditions in which each muscle can be found before the irreversible dystrophic alteration, marked as T1-weighted sequence hyperintensity, takes place. We studied these conditions in order to obtain further information on the molecular mechanisms involved in the selective wasting of single muscles or muscle groups in this disease. Histopathology, gene expression profiling and real time PCR were performed on biopsies from FSHD muscles with different MRI pattern (T1-weighted normal/T2-STIR normal and T1-weighted normal/T2-STIR hyperintense). Data were compared with those from inflammatory myopathies, dysferlinopathies and normal controls. In order to validate obtained results, two additional FSHD samples with different MRI pattern were analyzed. Myopathic and inflammatory changes characterized T2-STIR hyperintense FSHD muscles, at variance with T2-STIR normal muscles. These two states could be easily distinguished from each other by their transcriptional profile. The comparison between T2-STIR hyperintense FSHD muscles and inflammatory myopathy muscles showed peculiar changes, although many alterations were shared among these conditions. At the single muscle level, different stages of the disease correspond to the two MRI patterns. T2-STIR hyperintense FSHD muscles are more similar to inflammatory myopathies than to T2-STIR normal FSHD muscles or other muscular dystrophies, and share with them upregulation of genes involved in innate and adaptive immunity. Our data suggest that selective inflammation, together with perturbation in biological processes such as neoangiogenesis, lipid metabolism and adipokine production, may contribute

  6. Assessing the consistency of UAV-derived point clouds and images acquired at different altitudes

    Science.gov (United States)

    Ozcan, O.

    2016-12-01

    Unmanned Aerial Vehicles (UAVs) offer several advantages in terms of cost and image resolution compared to terrestrial photogrammetry and satellite remote sensing system. Nowadays, UAVs that bridge the gap between the satellite scale and field scale applications were initiated to be used in various application areas to acquire hyperspatial and high temporal resolution imageries due to working capacity and acquiring in a short span of time with regard to conventional photogrammetry methods. UAVs have been used for various fields such as for the creation of 3-D earth models, production of high resolution orthophotos, network planning, field monitoring and agricultural lands as well. Thus, geometric accuracy of orthophotos and volumetric accuracy of point clouds are of capital importance for land surveying applications. Correspondingly, Structure from Motion (SfM) photogrammetry, which is frequently used in conjunction with UAV, recently appeared in environmental sciences as an impressive tool allowing for the creation of 3-D models from unstructured imagery. In this study, it was aimed to reveal the spatial accuracy of the images acquired from integrated digital camera and the volumetric accuracy of Digital Surface Models (DSMs) which were derived from UAV flight plans at different altitudes using SfM methodology. Low-altitude multispectral overlapping aerial photography was collected at the altitudes of 30 to 100 meters and georeferenced with RTK-GPS ground control points. These altitudes allow hyperspatial imagery with the resolutions of 1-5 cm depending upon the sensor being used. Preliminary results revealed that the vertical comparison of UAV-derived point clouds with respect to GPS measurements pointed out an average distance at cm-level. Larger values are found in areas where instantaneous changes in surface are present.

  7. Hyperspectral imaging for small-scale analysis of symptoms caused by different sugar beet diseases

    Directory of Open Access Journals (Sweden)

    Mahlein Anne-Katrin

    2012-01-01

    Full Text Available Abstract Hyperspectral imaging (HSI offers high potential as a non-invasive diagnostic tool for disease detection. In this paper leaf characteristics and spectral reflectance of sugar beet leaves diseased with Cercospora leaf spot, powdery mildew and leaf rust at different development stages were connected. Light microscopy was used to describe the morphological changes in the host tissue due to pathogen colonisation. Under controlled conditions a hyperspectral imaging line scanning spectrometer (ImSpector V10E with a spectral resolution of 2.8 nm from 400 to 1000 nm and a spatial resolution of 0.19 mm was used for continuous screening and monitoring of disease symptoms during pathogenesis. A pixel-wise mapping of spectral reflectance in the visible and near-infrared range enabled the detection and detailed description of diseased tissue on the leaf level. Leaf structure was linked to leaf spectral reflectance patterns. Depending on the interaction with the host tissue, the pathogens caused disease-specific spectral signatures. The influence of the pathogens on leaf reflectance was a function of the developmental stage of the disease and of the subarea of the symptoms. Spectral reflectance in combination with Spectral Angle Mapper classification allowed for the differentiation of mature symptoms into zones displaying all ontogenetic stages from young to mature symptoms. Due to a pixel-wise extraction of pure spectral signatures a better understanding of changes in leaf reflectance caused by plant diseases was achieved using HSI. This technology considerably improves the sensitivity and specificity of hyperspectrometry in proximal sensing of plant diseases.

  8. Imaging genetics and the neurobiological basis of individual differences in vulnerability to addiction.

    Science.gov (United States)

    Sweitzer, Maggie M; Donny, Eric C; Hariri, Ahmad R

    2012-06-01

    Addictive disorders are heritable, but the search for candidate functional polymorphisms playing an etiological role in addiction is hindered by complexity of the phenotype and the variety of factors interacting to impact behavior. Advances in human genome sequencing and neuroimaging technology provide an unprecedented opportunity to explore the impact of functional genetic variants on variability in behaviorally relevant neural circuitry. Here, we present a model for merging these technologies to trace the links between genes, brain, and addictive behavior. We describe imaging genetics and discuss the utility of its application to addiction. We then review data pertaining to impulsivity and reward circuitry as an example of how genetic variation may lead to variation in behavioral phenotype. Finally, we present preliminary data relating the neural basis of reward processing to individual differences in nicotine dependence. Complex human behaviors such as addiction can be traced to their basic genetic building blocks by identifying intermediate behavioral phenotypes, associated neural circuitry, and underlying molecular signaling pathways. Impulsivity has been linked with variation in reward-related activation in the ventral striatum (VS), altered dopamine signaling, and functional polymorphisms of DRD2 and DAT1 genes. In smokers, changes in reward-related VS activation induced by smoking abstinence may be associated with severity of nicotine dependence. Variation in genes related to dopamine signaling may contribute to heterogeneity in VS sensitivity to reward and, ultimately, to addiction. These findings illustrate the utility of the imaging genetics approach for investigating the neurobiological basis for vulnerability to addiction. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  9. Application of near-infrared hyperspectral imaging to discriminate different geographical origins of Chinese wolfberries.

    Directory of Open Access Journals (Sweden)

    Wenxin Yin

    Full Text Available Near-infrared (874-1734 nm hyperspectral imaging (NIR-HSI technique combined with chemometric methods was used to trace origins of 1200 Chinese wolfberry samples, which from Ningxia, Inner Mongolia, Sinkiang and Qinghai in China. Two approaches, named pixel-wise and object-wise, were investigated to discriminative the origin of these Chinese wolfberries. The pixel-wise classification assigned a class to each pixel from individual Chinese wolfberries, and with this approach, the differences in the Chinese wolfberries from four origins were reflected intuitively. Object-wise classification was performed using mean spectra. The average spectral information of all pixels of each sample in the hyperspectral image was extracted as the representative spectrum of a sample, and then discriminant analysis models of the origins of Chinese wolfberries were established based on these average spectra. Specifically, the spectral curves of all samples were collected, and after removal of obvious noise, the spectra of 972-1609 nm were viewed as the spectra of wolfberry. Then, the spectral curves were pretreated with moving average smoothing (MA, and discriminant analysis models including support vector machine (SVM, neural network with radial basis function (NN-RBF and extreme learning machine (ELM were established based on the full-band spectra, the extracted characteristic wavelengths from loadings of principal component analysis (PCA and 2nd derivative spectra, respectively. Among these models, the recognition accuracies of the calibration set and prediction set of the ELM model based on extracted characteristic wavelengths from loadings of PCA were higher than 90%. The model not only ensured a high recognition rate but also simplified the model and was conducive to future rapid on-line testing. The results revealed that NIR-HSI combined with PCA loadings-ELM could rapidly trace the origins of Chinese wolfberries.

  10. Application of near-infrared hyperspectral imaging to discriminate different geographical origins of Chinese wolfberries.

    Science.gov (United States)

    Yin, Wenxin; Zhang, Chu; Zhu, Hongyan; Zhao, Yanru; He, Yong

    2017-01-01

    Near-infrared (874-1734 nm) hyperspectral imaging (NIR-HSI) technique combined with chemometric methods was used to trace origins of 1200 Chinese wolfberry samples, which from Ningxia, Inner Mongolia, Sinkiang and Qinghai in China. Two approaches, named pixel-wise and object-wise, were investigated to discriminative the origin of these Chinese wolfberries. The pixel-wise classification assigned a class to each pixel from individual Chinese wolfberries, and with this approach, the differences in the Chinese wolfberries from four origins were reflected intuitively. Object-wise classification was performed using mean spectra. The average spectral information of all pixels of each sample in the hyperspectral image was extracted as the representative spectrum of a sample, and then discriminant analysis models of the origins of Chinese wolfberries were established based on these average spectra. Specifically, the spectral curves of all samples were collected, and after removal of obvious noise, the spectra of 972-1609 nm were viewed as the spectra of wolfberry. Then, the spectral curves were pretreated with moving average smoothing (MA), and discriminant analysis models including support vector machine (SVM), neural network with radial basis function (NN-RBF) and extreme learning machine (ELM) were established based on the full-band spectra, the extracted characteristic wavelengths from loadings of principal component analysis (PCA) and 2nd derivative spectra, respectively. Among these models, the recognition accuracies of the calibration set and prediction set of the ELM model based on extracted characteristic wavelengths from loadings of PCA were higher than 90%. The model not only ensured a high recognition rate but also simplified the model and was conducive to future rapid on-line testing. The results revealed that NIR-HSI combined with PCA loadings-ELM could rapidly trace the origins of Chinese wolfberries.

  11. Body image concerns: levels, correlates and gender differences among students in the United Kingdom.

    Science.gov (United States)

    El Ansari, Walid; Dibba, Emily; Stock, Christiane

    2014-06-01

    This cross-sectional study aimed to determine the socio-demographic, lifestyle and well-being variables that are associated with body image concerns (BIC) and whether these associations differed between female and male students. A cross-sectional survey; 3,706 undergraduate students (2,699 females, 765 males) from seven universities in the UK completed a self-administered questionnaire that assessed socio-demographic, lifestyle, well-being and BIC based on the Body Shape Questionnaire developed by Cooper et al. Multifactorial logistic regression analysis examined the odds ratios for the association between four increasing levels of BIC as the dependent variables (no BIC, mild BIC, moderate BIC and marked BIC) on the one hand, and the socio-demographic (gender, age, year at university), lifestyle (physical activity, nutrition) and mental well-being variables (quality of life, perceived stress, perceived health, depressive symptoms) on the other. More females (35%) than males (8%) reported being moderately or markedly concerned with their body image. For both genders, BIC was associated with a higher level of depressive symptoms and to variable extents, with nutrition and year at university. Females' BICs were exclusively associated with low perceived health, higher perceived stress, studies in general as a stressor, and low physical activity. In contrast, males' BIC were found to be exclusively associated with low quality of life and with older age. Health promoting strategies and activities should address the co-occurrence of depressive symptoms and BIC and should moreover pay attention to the gender-specific correlates of BIC for tailoring evidence based interventions for females and for males.

  12. Imaging by the SSFSE single slice method at different viscosities of bile

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, Hiroya; Usui, Motoki; Fukunaga, Kenichi; Yamamoto, Naruto; Ikegami, Toshimi [Kawasaki Hospital, Kobe (Japan)

    2001-11-01

    The single shot fast spin echo single thick slice method (single slice method) is a technique that visualizes the water component alone using a heavy T{sub 2}. However, this method is considered to be markedly affected by changes in the viscosity of the material because a very long TE is used, and changes in the T{sub 2} value, which are related to viscosity, directly affect imaging. In this study, we evaluated the relationship between the effects of TE and the T{sub 2} value of bile in the single slice method and also examined the relationship between the signal intensity of bile on T{sub 1}- and T{sub 2}-weighted images and imaging by MR cholangiography (MRC). It was difficult to image bile with high viscosities at a usual effective TE level of 700-1,500 ms. With regard to the relationship between the signal intensity of bile and MRC imaging, all T{sub 2} values of the bile samples showing relatively high signal intensities on the T{sub 1}-weighted images suggested high viscosities, and MRC imaging of these bile samples was poor. In conclusion, MRC imaging of bile with high viscosities was poor with the single slice method. Imaging by the single slice method alone of bile showing a relatively high signal intensity on T{sub 1}-weighted images should be avoided, and combination with other MRC sequences should be used. (author)

  13. Genetically encoded fluorescent indicator for imaging NAD(+)/NADH ratio changes in different cellular compartments.

    Science.gov (United States)

    Bilan, Dmitry S; Matlashov, Mikhail E; Gorokhovatsky, Andrey Yu; Schultz, Carsten; Enikolopov, Grigori; Belousov, Vsevolod V

    2014-03-01

    The ratio of NAD(+)/NADH is a key indicator that reflects the overall redox state of the cells. Until recently, there were no methods for real time NAD(+)/NADH monitoring in living cells. Genetically encoded fluorescent probes for NAD(+)/NADH are fundamentally new approach for studying the NAD(+)/NADH dynamics. We developed a genetically encoded probe for the nicotinamide adenine dinucleotide, NAD(H), redox state changes by inserting circularly permuted YFP into redox sensor T-REX from Thermus aquaticus. We characterized the sensor in vitro using spectrofluorometry and in cultured mammalian cells using confocal fluorescent microscopy. The sensor, named RexYFP, reports changes in the NAD(+)/NADH ratio in different compartments of living cells. Using RexYFP, we were able to track changes in NAD(+)/NADH in cytoplasm and mitochondrial matrix of cells under a variety of conditions. The affinity of the probe enables comparison of NAD(+)/NADH in compartments with low (cytoplasm) and high (mitochondria) NADH concentration. We developed a method of eliminating pH-driven artifacts by normalizing the signal to the signal of the pH sensor with the same chromophore. RexYFP is suitable for detecting the NAD(H) redox state in different cellular compartments. RexYFP has several advantages over existing NAD(+)/NADH sensors such as smallest size and optimal affinity for different compartments. Our results show that normalizing the signal of the sensor to the pH changes is a good strategy for overcoming pH-induced artifacts in imaging. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. A comparison of three different adaptive strategies in image-guided radiotherapy of bladder cancer

    Energy Technology Data Exchange (ETDEWEB)

    Vestergaard, Anne; Soendergaard, Jimmi; Petersen, Joergen B. (Dept. of Medical Physics, Aarhus Univ. Hospital, Noerrebrogade 44, DK-8000 Aarhus C (Denmark)), E-mail: annveste@rm.dk; Hoeyer, Morten; Muren, Ludvig Paul (Dept. of Oncology, Aarhus Univ. Hospital, Noerrebrogade 44, DK-8000 Aarhus C (Denmark))

    2010-10-15

    The urinary bladder shows considerable individual variation in shape and position during a course of radiotherapy (RT). In this study we have developed and compared three different adaptive RT (ART) strategies for bladder cancer involving daily cone beam CT (CBCT) imaging and plan selection. Material and methods. Ten patients treated for bladder cancer had daily CBCTs acquired that were registered online using bony anatomy registration. Seven patients received intensity modulated RT (IMRT) with a simultaneous integrated boost (SIB) technique to the bladder and pelvic lymph nodes. Three patients received treatment to the bladder only. Retrospectively, we compared three ART strategies that were all based on daily selection of the most suitable plan from a library consisting of three IMRT-plans corresponding to a small, medium and large target volume. ART method A utilised population-based margins while methods B and C used the bladder as seen on CBCT-scans from the first week of treatment; method B without delineation of the bladder on CBCT and method C with delineation of the bladder. Total dose distributions were calculated using the planning CT. For each patient, we calculated ratios of the dose volume histograms (DVHs) for the three ART strategies relative to non-adaptive therapy. Results. The inter-patient variation was large for all three ART strategies. The mean ratios of the volumes receiving 57 Gy or more (corresponding to 95% of prescribed dose) for methods A, B and C were 0.66 (SD: 0.11), 0.67 (SD: 0.13) and 0.67 (SD: 0.16) respectively when compared to the non-adaptive plan. Conclusion. When using any of the ART strategies, it is possible to reduce significantly the volumes receiving high doses compared to the use of a standard non-adaptive plan. The differences in dose volume parameters between the three methods were small compared with the differences from the standard plan.

  15. Accounting for pharmacokinetic differences in dual-tracer receptor density imaging.

    Science.gov (United States)

    Tichauer, K M; Diop, M; Elliott, J T; Samkoe, K S; Hasan, T; St Lawrence, K; Pogue, B W

    2014-05-21

    Dual-tracer molecular imaging is a powerful approach to quantify receptor expression in a wide range of tissues by using an untargeted tracer to account for any nonspecific uptake of a molecular-targeted tracer. This approach has previously required the pharmacokinetics of the receptor-targeted and untargeted tracers to be identical, requiring careful selection of an ideal untargeted tracer for any given targeted tracer. In this study, methodology capable of correcting for tracer differences in arterial input functions, as well as binding-independent delivery and retention, is derived and evaluated in a mouse U251 glioma xenograft model using an Affibody tracer targeted to epidermal growth factor receptor (EGFR), a cell membrane receptor overexpressed in many cancers. Simulations demonstrated that blood, and to a lesser extent vascular-permeability, pharmacokinetic differences between targeted and untargeted tracers could be quantified by deconvolving the uptakes of the two tracers in a region of interest devoid of targeted tracer binding, and therefore corrected for, by convolving the uptake of the untargeted tracer in all regions of interest by the product of the deconvolution. Using fluorescently labeled, EGFR-targeted and untargeted Affibodies (known to have different blood clearance rates), the average tumor concentration of EGFR in four mice was estimated using dual-tracer kinetic modeling to be 3.9 ± 2.4 nM compared to an expected concentration of 2.0 ± 0.4 nM. However, with deconvolution correction a more equivalent EGFR concentration of 2.0 ± 0.4 nM was measured.

  16. Functional magnetic resonance imaging of the human spinal cord during vibration stimulation of different dermatomes.

    Science.gov (United States)

    Lawrence, Jane M; Stroman, Patrick W; Kollias, Spyros S

    2008-03-01

    We investigated noninvasively areas of the healthy human spinal cord that become active in response to vibration stimulation of different dermatomes using functional magnetic resonance imaging (fMRI). The objectives of this study were to: (1) examine the patterns of consistent activity in the spinal cord during vibration stimulation of the skin, and (2) investigate the rostrocaudal distribution of active pixels when stimulation was applied to different dermatomes. FMRI of the cervical and lumbar spinal cord of seven healthy human subjects was carried out during vibration stimulation of six different dermatomes. In separate experiments, vibratory stimulation (about 50 Hz) was applied to the right biceps, wrist, palm, patella, Achilles tendon and left palm. The segmental distribution of activity observed by fMRI corresponded well with known spinal cord neuroanatomy. The peak number of active pixels was observed at the expected level of the spinal cord with some activity in the adjacent segments. The rostrocaudal distribution of activity was observed to correspond to the dermatome being stimulated. Cross-sectional localization of activity was primarily in dorsal areas but also spread into ventral and intermediate areas of the gray matter and a distinct laterality ipsilateral to the stimulated limb was not observed. We demonstrated that fMRI can detect a dermatome-dependent pattern of spinal cord activity during vibratory stimulation and can be used as a passive stimulus for the noninvasive assessment of the functional integrity of the human spinal cord. Demonstration of cross-sectional selectivity of the activation awaits further methodological and experimental refinements.

  17. Functional magnetic resonance imaging of the human spinal cord during vibration stimulation of different dermatomes

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, Jane M. [University Hospital of Zurich, Institute of Neuroradiology, Zurich (Switzerland); University of Manitoba, Department of Physiology, Winnipeg, Manitoba (Canada); Stroman, Patrick W. [Queen' s University, Department of Diagnostic Radiology, Kingston, Ontario (Canada); Kollias, Spyros S. [University Hospital of Zurich, Institute of Neuroradiology, Zurich (Switzerland)

    2008-03-15

    We investigated noninvasively areas of the healthy human spinal cord that become active in response to vibration stimulation of different dermatomes using functional magnetic resonance imaging (fMRI). The objectives of this study were to: (1) examine the patterns of consistent activity in the spinal cord during vibration stimulation of the skin, and (2) investigate the rostrocaudal distribution of active pixels when stimulation was applied to different dermatomes. FMRI of the cervical and lumbar spinal cord of seven healthy human subjects was carried out during vibration stimulation of six different dermatomes. In separate experiments, vibratory stimulation (about 50 Hz) was applied to the right biceps, wrist, palm, patella, Achilles tendon and left palm. The segmental distribution of activity observed by fMRI corresponded well with known spinal cord neuroanatomy. The peak number of active pixels was observed at the expected level of the spinal cord with some activity in the adjacent segments. The rostrocaudal distribution of activity was observed to correspond to the dermatome being stimulated. Cross-sectional localization of activity was primarily in dorsal areas but also spread into ventral and intermediate areas of the gray matter and a distinct laterality ipsilateral to the stimulated limb was not observed. We demonstrated that fMRI can detect a dermatome-dependent pattern of spinal cord activity during vibratory stimulation and can be used as a passive stimulus for the noninvasive assessment of the functional integrity of the human spinal cord. Demonstration of cross-sectional selectivity of the activation awaits further methodological and experimental refinements. (orig.)

  18. MR Brain Image Segmentation: A Framework to Compare Different Clustering Techniques

    OpenAIRE

    Laura Caponetti; Giovanna Castellano; Vito Corsini

    2017-01-01

    In Magnetic Resonance (MR) brain image analysis, segmentation is commonly used for detecting, measuring and analyzing the main anatomical structures of the brain and eventually identifying pathological regions. Brain image segmentation is of fundamental importance since it helps clinicians and researchers to concentrate on specific regions of the brain in order to analyze them. However, segmentation of brain images is a difficult task due to high similarities and correlations of intensity amo...

  19. Adult Attachment and Motivated Attention to Social Images: Attachment-Based Differences in Event-Related Brain Potentials to Emotional Images.

    Science.gov (United States)

    Chavis, J M; Kisley, Michael A

    2012-02-01

    Differences in adult attachment may concord with differences in social perception. The present study aimed to measure neural activity associated with the presentation of visual social stimuli. In an affective oddball paradigm, event-related brain potentials were recorded while participants viewed negative, positive, and neutral images of people and categorized them according to valence. Brain response amplitudes were examined across valence categories and across attachment groups. Results revealed differences between anxious and avoidant groups in "emotion bias." The avoidant group displayed a bias towards more neural activation in response to negative compared to positive images. The anxious group trended in the opposite direction. Results are discussed in terms of possible attachment-based differences in motivated attention to social stimuli.

  20. Dual-mode super-resolution imaging with stimulated emission depletion microscopy and fluorescence emission difference microscopy.

    Science.gov (United States)

    Wang, Yifan; Ma, Ye; Kuang, Cuifang; Fang, Yue; Xu, Yingke; Liu, Xu; Ding, Zhihua

    2015-06-10

    Dual-mode super-resolution imaging system with two different super-resolution imaging methods, STED and FED, is presented. Electrical shutters controlled by the host computer are introduced to switch the two imaging modes. Principles of both methods are analyzed theoretically, and enhancements in the lateral resolution and SNR are demonstrated theoretically and experimentally. Results show that both imaging methods offered by the proposed system can break the diffraction barrier. Furthermore, the presented system provides a meaningful way to image fluorescent samples by a corresponding imaging mode according to the specific characteristics of samples analyzed for study. For samples that can endure high-power illumination, it is appropriate to use the STED mode to achieve a better resolution, while for samples that are vulnerable to high intensity, the FED method is a better choice because no high-power beam is needed, and the FED method can provide better resolution than STED when no high-power beam is allowed. The flexible switching of the two super-resolution imaging modes can help researchers to make most of the advantages of each imaging method. It is believed that the presented system has the potential to be widely used in future nanoscale investigations.

  1. Applicability of the DAST-C to the Images of Scientists Drawn by Students of Different Racial Groups.

    Science.gov (United States)

    Finson, Kevin D.

    2003-01-01

    Describes the Draw-a-Scientist Test-Checklist (DAST-C) and discusses concerns regarding stereotypical images and their specific influences on students' perceptions. Reports on a study examining the difference between the drawings of 8th grade students from different ethnic backgrounds using the DAST-C. (Contains 21 references.) (Author/YDS)

  2. Gender Differences in Turkish Primary Students' Images of Astronomical Scientists: A Preliminary Study with 21st Century Style

    Science.gov (United States)

    Korkmaz, Hunkar

    2009-01-01

    This study investigated the images of astronomical scientists held by Turkish primary students by gender. The Draw an Astronomical Scientist Test was administered to 472 students from an urban area. A Chi-Square Test of Independence was used to test for statistically significant differences between gender groups. Significant differences were found…

  3. Investigation of perceived image quality and colourfulness in mobile displays for different cultures, ambient illumination, and resolution.

    Science.gov (United States)

    Lin, Po-Hung; Patterson, Patrick

    2012-01-01

    This study explored the effects of culture, ambient illumination, and resolution on perceived image quality and colourfulness of mobile displays. Thirty Taiwanese and 30 American students participated in the experiment. Two types of culture (Taiwanese and American), two types of illumination level (1500 lux and 7000 lux), and five types of resolution level (320×240, 260×208, 200×160, 140×112, and 80×64) were investigated in the experiment. Interactions between culture and resolution, and between illumination and resolution, were found for both perceived image quality and colourfulness. The results indicated that subjects were able to detect smaller differences in perceived image quality but not for colourfulness, and Taiwanese subjects could detect smaller differences than could the American subjects for both perceived image quality and colourfulness. The results further indicated that Taiwanese subjects were able to detect smaller differences at most of the resolution levels for colourfulness in 1500 lux than were the American subjects. This study found, from culture differences and ergonomics considerations, that Taiwanese subjects could detect smaller differences than could American subjects when evaluating perceived image quality and colourfulness on mobile displays. Mobile display manufacturers can use the results of this study as a reference for future mobile display design.

  4. Multispectral Enhancement Method to Increase the Visual Differences of Tissue Structures in Stained Histopathology Images

    Directory of Open Access Journals (Sweden)

    Pinky A. Bautista

    2012-01-01

    Full Text Available In this paper we proposed a multispectral enhancement scheme in which the spectral colors of the stained tissue-structure of interest and its background can be independently modified by the user to further improve their visualization and color discrimination. The colors of the background objects are modified by transforming their N-band spectra through an NxN transformation matrix, which is derived by mapping the representative samples of their original spectra to the spectra of their target colors using least mean square method. On the other hand, the color of the tissue structure of interest is modified by modulating the transformed spectra with the sum of the pixel’s spectral residual-errors at specific bands weighted through an NxN weighting matrix; the spectral error is derived by taking the difference between the pixel’s original spectrum and its reconstructed spectrum using the first M dominant principal component vectors in principal component analysis. Promising results were obtained on the visualization of the collagen fiber and the non-collagen tissue structures, e.g., nuclei, cytoplasm and red blood cells (RBC, in a hematoxylin and eosin (H&E stained image.

  5. Evaluation of 3 different registration techniques in image-guided bimaxillary surgery.

    Science.gov (United States)

    Sun, Yi; Luebbers, Heinz-Theo; Agbaje, Jimoh Olubanwo; Schepers, Serge; Vrielinck, Luc; Lambrichts, Ivo; Politis, Constantinus

    2013-07-01

    Perioperative navigation is an upcoming tool in orthognathic surgery. This study aimed to access the feasibility of the technique and to evaluate the success rate of 3 different registration methods--facial surface registration, anatomic landmark-based registration, and template-based registration. The BrainLab navigation system (BrainLab AG, Feldkirchen, Germany) was used as an additional precision tool for 85 patients who underwent bimaxillary orthognathic surgery from February 2010 to June 2012. Eighteen cases of facial surface-based registration, 63 cases of anatomic landmark-based registration, and 8 cases of template-based registration were analyzed. The overall success rate of facial surface-based registration was 39%, which was significant lower than template-based (100%, P = 0.013) and anatomic landmark-based registration (95%, P registration, the further procedure of surgical navigation was performed. The concept of navigation of the maxilla during bimaxillary orthognathic surgery has been proved to be feasible. The registration process is the critical point regarding success of intraoperative navigation. Anatomic landmark-based registration is a reliable technique for image-guided bimaxillary surgery. In contrast, facial surface-based registration is highly unreliable.

  6. Searching for transits in the WTS with the difference imaging light curves

    Science.gov (United States)

    Zendejas Dominguez, Jesus

    2013-12-01

    The search for exo-planets is currently one of the most exiting and active topics in astronomy. Small and rocky planets are particularly the subject of intense research, since if they are suitably located from their host star, they may be warm and potentially habitable worlds. On the other hand, the discovery of giant planets in short-period orbits provides important constraints on models that describe planet formation and orbital migration theories. Several projects are dedicated to discover and characterize planets outside of our solar system. Among them, the Wide-Field Camera Transit Survey (WTS) is a pioneer program aimed to search for extra-solar planets, that stands out for its particular aims and methodology. The WTS has been in operation since August 2007 with observations from the United Kingdom Infrared Telescope, and represents the first survey that searches for transiting planets in the near-infrared wavelengths; hence the WTS is designed to discover planets around M-dwarfs. The survey was originally assigned about 200 nights, observing four fields that were selected seasonally (RA = 03, 07, 17 and 19h) during a year. The images from the survey are processed by a data reduction pipeline, which uses aperture photometry to construct the light curves. For the most complete field (19h-1145 epochs) in the survey, we produce an alternative set of light curves by using the method of difference imaging, which is a photometric technique that has shown important advantages when used in crowded fields. A quantitative comparison between the photometric precision achieved with both methods is carried out in this work. We remove systematic effects using the sysrem algorithm, scale the error bars on the light curves, and perform a comparison of the corrected light curves. The results show that the aperture photometry light curves provide slightly better precision for objects with J light curves present a significant improvement for fainter stars. In order to detect

  7. Normalization of cortical thickness measurements across different T1 magnetic resonance imaging protocols by novel W-Score standardization.

    Science.gov (United States)

    Chung, Jinyong; Yoo, Kwangsun; Lee, Peter; Kim, Chan Mi; Roh, Jee Hoon; Park, Ji Eun; Kim, Sang Joon; Seo, Sang Won; Shin, Jeong-Hyeon; Seong, Joon-Kyung; Jeong, Yong

    2017-10-01

    The use of different 3D T1-weighted magnetic resonance (T1 MR) imaging protocols induces image incompatibility across multicenter studies, negating the many advantages of multicenter studies. A few methods have been developed to address this problem, but significant image incompatibility still remains. Thus, we developed a novel and convenient method to improve image compatibility. W-score standardization creates quality reference values by using a healthy group to obtain normalized disease values. We developed a protocol-specific w-score standardization to control the protocol effect, which is applied to each protocol separately. We used three data sets. In dataset 1, brain T1 MR images of normal controls (NC) and patients with Alzheimer's disease (AD) from two centers, acquired with different T1 MR protocols, were used (Protocol 1 and 2, n = 45/group). In dataset 2, data from six subjects, who underwent MRI with two different protocols (Protocol 1 and 2), were used with different repetition times, echo times, and slice thicknesses. In dataset 3, T1 MR images from a large number of healthy normal controls (Protocol 1: n = 148, Protocol 2: n = 343) were collected for w-score standardization. The protocol effect and disease effect on subjects' cortical thickness were analyzed before and after the application of protocol-specific w-score standardization. As expected, different protocols resulted in differing cortical thickness measurements in both NC and AD subjects. Different measurements were obtained for the same subject when imaged with different protocols. Multivariate pattern difference between measurements was observed between the protocols. Classification accuracy between two protocols was nearly 90%. After applying protocol-specific w-score standardization, the differences between the protocols substantially decreased. Most importantly, protocol-specific w-score standardization reduced both univariate and multivariate differences in the images while

  8. Do basic psychomotor skills transfer between different image-based procedures?

    Science.gov (United States)

    Buzink, Sonja N; Goossens, Richard H M; Schoon, Erik J; de Ridder, Huib; Jakimowicz, Jack J

    2010-05-01

    Surgical techniques that draw from multiple types of image-based procedures (IBP) are increasing, such as Natural Orifice Transluminal Endoscopic Surgery, fusing laparoscopy and flexible endoscopy. However, little is known about the relation between psychomotor skills for performing different types of IBP. For example, do basic psychomotor colonoscopy and laparoscopy skills interact? Following a cross-over study design, 29 naïve endoscopists were trained on the Simbionix GI Mentor and the SimSurgery SEP simulators. Group C (n = 15) commenced with a laparoscopy session, followed by four colonoscopy sessions and a second laparoscopy session. Group L (n = 14) started with a colonoscopy session, followed by four laparoscopy sessions and a second colonoscopy session. No significant differences were found between the performances of group L and group C in their first training sessions on either technique. With additional colonoscopy training, group C outperformed group L in the second laparoscopy training session on the camera navigation task. Overall, training in the basic colonoscopy tasks does not affect performance of basic laparoscopy tasks (and vice versa). However, to limited extent, training of basic psychomotor skills for colonoscopy do appear to contribute to the performance of angled laparoscope navigation tasks. Thus, training and assessment of IBP type-specific skills should focus on each type of tasks independently. Future research should further investigate the influence of psychometric abilities on the performance of IBP and the transfer of skills for physicians who are experienced in one IBP type and would like to become proficient in another type of IBP.

  9. Fluorescence lifetime images of different green fluorescent proteins in fly brain

    Science.gov (United States)

    Lai, Sih-Yu; Lin, Y. Y.; Chiang, A. S.; Huang, Y. C.

    2009-02-01

    The mechanisms of learning and memory are the most important functions in an animal brain. Investigating neuron circuits and network maps in a brain is the first step toward understanding memory and learning behavior. Since Drosophila brain is the major model for understanding brain functions, we measure the florescence lifetimes of different GFP-based reporters expressed in a fly brain. In this work, two Gal4 drivers, OK 107 and MZ 19 were used. Intracellular calcium ([Ca2+]) concentration is an importation indicator of neuronal activity. Therefore, several groups have developed GFP-based calcium sensors, among which G-CaMP is the most popular and reliable. The fluorescence intensity of G-CaMP will increase when it binds to calcium ion; however, individual variation from different animals prevents quantitative research. In this work, we found that the florescence lifetime of G-CaMP will shrink from 1.8 ns to 1.0 ns when binding to Ca2+. This finding can potentially help us to understand the neuron circuits by fluorescence lifetime imaging microscopy (FLIM). Channelrhodopsin-2 (ChR2) is a light-activated ion-channel protein on a neuron cell membrane. In this work, we express ChR2 and G-CaMP in a fly brain. Using a pulsed 470-nm laser to activate the neurons, we can also record the fluorescence lifetime changes in the structure. Hence, we can trace and manipulate a specific circuit in this animal. This method provides more flexibility in brain research.

  10. Detail displaying difference of the digital holographic reconstructed image between the convolution algorithm and Fresnel algorithm.

    Science.gov (United States)

    Zhong, Liyun; Li, Hongyan; Tao, Tao; Zhang, Zhun; Lu, Xiaoxu

    2011-11-07

    To reach the limiting resolution of a digital holographic system and improve the displaying quality of the reconstructed image, the subdivision convolution algorithm and the subdivision Fresnel algorithm are presented, respectively. The obtained results show that the lateral size of the reconstructed image obtained by two kinds of subdivision algorithms is the same in the central region of the reconstructed image-plane; moreover, the size of the central region is in proportional to the recording distance. Importantly, in the central region of the reconstructed image-plane, the reconstruction can be performed by the subdivision Fresnel algorithm instead of the subdivision convolution algorithm effectively, and, based on these subdivision approaches, both the displaying quality and the resolution of the reconstructed image can be improved significantly. Furthermore, in the reconstruction of the digital hologram with the large numerical aperture, the computer's memory consumed and the calculating time resulting from the subdivision Fresnel algorithm is significantly less than those from the subdivision convolution algorithm.

  11. Multiscaling of vegetative indexes from remote sensing images obtained at different spatial resolutions

    Science.gov (United States)

    Alonso, Carmelo; Tarquis, Ana M.; Zuñiga, Ignacio; Benito, Rosa M.

    2017-04-01

    Vegetation indexes, such as Normalized Difference Vegetation Index (NDVI) and enhanced Vegetation index (EVI), can been used to estimate root zone soil moisture through high resolution remote sensing images. These indexes are based in red (R), near infrared (NIR) and blue (B) wavelengths data. In this work we have studied the scaling properties of both vegetation indexes analyzing the information contained in two satellite data: Landsat-7 and Ikonos. Because of the potential capacity for systematic observations at various scales, remote sensing technology extends possible data archives from present time to over several decades back. For this advantage, enormous efforts have been made by researchers and application specialists to delineate vegetation indexes from local scale to global scale by applying remote sensing imagery. To study the influence of the spatial resolution the vegetation indexes map estimated with Ikonos-2 coded in 8 bits, with a resolution of 4m, have been compared through a multifractal analysis with the ones obtained with Lansat-7 8 bits, of 30 m. resolution, on the same area of study. The scaling behaviour of NDVI and EVI presents several differences that will be discussed based on the multifractal parameters extracted from the analysis. REFERENCES Alonso, C., Tarquis, A. M., Benito, R. M. and Zuñiga, I. Correlation scaling properties between soil moisture and vegetation indices. Geophysical Research Abstracts, 11, EGU2009-13932, 2009. Alonso, C., Tarquis, A. M. and Benito, R. M. Comparison of fractal dimensions based on segmented NDVI fields obtained from different remote sensors. Geophysical Research Abstracts, 14, EGU2012-14342, 2012. Escribano Rodriguez, J., Alonso, C., Tarquis, A.M., Benito, R.M. and Hernandez Diaz-Ambrona, C. Comparison of NDVI fields obtained from different remote sensors. Geophysical Research Abstracts,15, EGU2013-14153, 2013. Lovejoy, S., Tarquis, A., Gaonac'h, H. and Schertzer, D. Single and multiscale remote sensing

  12. Quantitative image analysis of polyhydroxyalkanoates inclusions from microbial mixed cultures under different SBR operation strategies.

    Science.gov (United States)

    Amaral, António L; Abreu, Hugo; Leal, Cristiano; Mesquita, Daniela P; Castro, Luís M; Ferreira, Eugénio C

    2017-06-01

    Polyhydroxyalkanoates (PHAs) produced from mixed microbial cultures (MMC), regarded as potential substitutes of petrochemical plastics, can be found as intracellular granules in various microorganisms under limited nutrient conditions and excess of carbon source. PHA is traditionally quantified by laborious and time-consuming chromatography analysis, and a simpler and faster method to assess PHA contents from MMC, such as quantitative image analysis (QIA), is of great interest. The main purpose of the present work was to upgrade a previously developed QIA methodology (as reported by Mesquita et al. (Anal Chim Acta 770:36-44, 2013a, Anal Chim Acta 865:8-15, 2015)) for MMC intracellular PHA contents quantification, increase the studied intracellular PHA concentration range, and extend to different sequencing batch reactor (SBR) operation strategies. Therefore, the operation of a new aerobic dynamic feeding (ADF) SBR allowed further extending the studied operating conditions, dataset, and range of the MMC intracellular PHA contents from the previously reported anaerobic/aerobic cycle SBR. Nile Blue A (NBA) staining was employed for epifluorescence microscope visualization and image acquisition, further fed to a custom developed QIA. Data from each of the feast and famine cycles of both SBR were individually processed using chemometrics analysis, obtaining the correspondent partial least squares (PLS) models. The PHA concentrations determined from PLS models were further plotted against the results obtained in the standard chromatographic method. For both SBR, the predicted ability was higher at the end of the feast stage than for the famine stage. Indeed, an independent feast and famine QIA data treatment was found to be fundamental to obtain the best prediction abilities. Furthermore, a promising overall correlation (R 2 of 0.83) could be found combining the overall QIA data regarding the PHA prediction up to a concentration of 1785.1 mg L-1 (37.3 wt%). Thus, the

  13. Performance Evaluation of Three Different High Resolution Satellite Images in Semi-Automatic Urban Illegal Building Detection

    Science.gov (United States)

    Khalilimoghadama, N.; Delavar, M. R.; Hanachi, P.

    2017-09-01

    The problem of overcrowding of mega cities has been bolded in recent years. To meet the need of housing this increased population, which is of great importance in mega cities, a huge number of buildings are constructed annually. With the ever-increasing trend of building constructions, we are faced with the growing trend of building infractions and illegal buildings (IBs). Acquiring multi-temporal satellite images and using change detection techniques is one of the proper methods of IB monitoring. Using the type of satellite images with different spatial and spectral resolutions has always been an issue in efficient detection of the building changes. In this research, three bi-temporal high-resolution satellite images of IRS-P5, GeoEye-1 and QuickBird sensors acquired from the west of metropolitan area of Tehran, capital of Iran, in addition to city maps and municipality property database were used to detect the under construction buildings with improved performance and accuracy. Furthermore, determining the employed bi-temporal satellite images to provide better performance and accuracy in the case of IB detection is the other purpose of this research. The Kappa coefficients of 70 %, 64 %, and 68 % were obtained for producing change image maps using GeoEye-1, IRS-P5, and QuickBird satellite images, respectively. In addition, the overall accuracies of 100 %, 6 %, and 83 % were achieved for IB detection using the satellite images, respectively. These accuracies substantiate the fact that the GeoEye-1 satellite images had the best performance among the employed images in producing change image map and detecting the IBs.

  14. Gender related differences in response to "in favor of myself" wellness program to enhance positive self & body image among adolescents.

    Science.gov (United States)

    Golan, Moria; Hagay, Noa; Tamir, Snait

    2014-01-01

    Physical, neurological and psychological changes are often experienced differently by male and female adolescents. Positive self-esteem, emotional well-being, school achievements, and family connectedness are considered as protective factors against health-compromising behaviors. This study examines the gender differences in respect to the effect of a school-based interactive wellness program--"In Favor of Myself"--on self-image, body image, eating attitudes and behaviors of young adolescents. Two hundred and ten adolescents (mean age 13.5) participated in the intervention group, 55% were girls and 45% boys. Program consisted of eight 90-minutes structured sessions integrated into a regular school coping skills curriculum. The program focused on self-esteem, self-image, body image, media literacy and cognitive dissonance. The overall impact of the program and the study protocol were previously published. Overall, there are gender related differences in respect to body image and self-image in young adolescents in response to "In Favor of Myself". Compared to boys, girls reported at baseline higher self-esteem, being more contingent by appearance, and their self-image was more influenced by popularity, appearance, interpersonal communication and admired people. Furthermore girls presented greater gap between current body figure and perceived ideal figure. Not only were girls more dissatisfied with their body, but they were more active in attempts to become and/or remain "thin". At program termination, gender × time effect was detected in reduction of self-worth contingent by others, change in importance given to achievements at schools, parents' perceptions, as well as the impact of comparisons to friends and family members on self-image. Girls exhibited more gains than boys from 'In Favor of Myself' which raise the questions about how effective would be the program when delivered in mixed gender groups vs. mono-gender groups.

  15. Gender related differences in response to "in favor of myself" wellness program to enhance positive self & body image among adolescents.

    Directory of Open Access Journals (Sweden)

    Moria Golan

    Full Text Available BACKGROUND: Physical, neurological and psychological changes are often experienced differently by male and female adolescents. Positive self-esteem, emotional well-being, school achievements, and family connectedness are considered as protective factors against health-compromising behaviors. This study examines the gender differences in respect to the effect of a school-based interactive wellness program--"In Favor of Myself"--on self-image, body image, eating attitudes and behaviors of young adolescents. METHODS: Two hundred and ten adolescents (mean age 13.5 participated in the intervention group, 55% were girls and 45% boys. Program consisted of eight 90-minutes structured sessions integrated into a regular school coping skills curriculum. The program focused on self-esteem, self-image, body image, media literacy and cognitive dissonance. The overall impact of the program and the study protocol were previously published. RESULTS: Overall, there are gender related differences in respect to body image and self-image in young adolescents in response to "In Favor of Myself". Compared to boys, girls reported at baseline higher self-esteem, being more contingent by appearance, and their self-image was more influenced by popularity, appearance, interpersonal communication and admired people. Furthermore girls presented greater gap between current body figure and perceived ideal figure. Not only were girls more dissatisfied with their body, but they were more active in attempts to become and/or remain "thin". At program termination, gender × time effect was detected in reduction of self-worth contingent by others, change in importance given to achievements at schools, parents' perceptions, as well as the impact of comparisons to friends and family members on self-image. CONCLUSIONS: Girls exhibited more gains than boys from 'In Favor of Myself' which raise the questions about how effective would be the program when delivered in mixed gender groups

  16. Evaluation of different magnetic resonance imaging contrast materials to be used as dummy markers in image-guided brachytherapy for gynecologic malignancies

    Energy Technology Data Exchange (ETDEWEB)

    Sales, Camila Pessoa; Carvalho, Heloisa de Andrade; Rubo, Rodrigo Augusto; Stuart, Silvia Radwanski; Rodrigues, Laura Natal, E-mail: camyps@gmail.com [Universidade de Sao Paulo (InRad/HC/FM/USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Instituto de Radiologia; Taverna, Khallil Chaim; Pastorello, Bruno Fraccini [Universidade de Sao Paulo (FM/USP), Sao Paulo, SP (Brazil). Departamento de Radiologia e Oncologia. Lab. de Ressonancia Magnetica em Neurorradiologia; Borgonovi, Arthur Felipe [Royal Philips Electronics, Eindhoven (Netherlands)

    2016-05-15

    Objective: to identify a contrast material that could be used as a dummy marker for magnetic resonance imaging. Materials and methods: magnetic resonance images were acquired with six different catheter-filling materials - water, glucose 50%, saline, olive oil, glycerin, and copper sulfate (CuSO{sub 4}) water solution (2.08 g/L) - inserted into compatible computed tomography/magnetic resonance imaging ring applicators placed in a phantom made of gelatin and CuSO{sub 4}. The best contrast media were tested in four patients with the applicators in place. Results: in T2-weighted sequences, the best contrast was achieved with the CuSO{sub 4}-filled catheters, followed by saline- and glycerin-filled catheters, which presented poor visualization. In addition (also in T2-weighted sequences), CuSO{sub 4} presented better contrast when tested in the phantom than when tested in the patients, in which it provided some contrast but with poor identification of the first dwell position, mainly in the ring. Conclusion: we found CuSO{sub 4} to be the best solution for visualization of the applicator channels, mainly in T2-weighted images in vitro, although the materials tested presented low signal intensity in the images obtained in vivo, as well as poor precision in determining the first dwell position. (author)

  17. Characterization of Pure Ductal Carcinoma In Situ on Dynamic Contrast-Enhanced MR Imaging: Do Nonhigh Grade and High Grade Show Different Imaging Features?

    Directory of Open Access Journals (Sweden)

    Siwa Chan

    2010-01-01

    Full Text Available To characterize imaging features of pure DCIS on dynamic contrast-enhanced MR imaging (DCE-MRI, 31 consecutive patients (37-81 years old, mean 56, including 2 Grade I, 16 Grade II, and 13 Grade III, were studied. MR images were reviewed retrospectively and the morphological appearances and kinetic features of breast lesions were categorized according to the ACR BI-RADS breast MRI lexicon. DCE-MRI was a sensitive imaging modality in detecting pure DCIS. MR imaging showed enhancing lesions in 29/31 (94% cases. Pure DCIS appeared as mass type or non-mass lesions on MRI with nearly equal frequency. The 29 MR detected lesions include 15 mass lesions (52%, and 14 lesions showing non-mass-like lesions (48%. For the mass lesions, the most frequent presentations were irregular shape (50%, irregular margin (50% and heterogeneous enhancement (67%. For the non-mass-like lesions, the clumped internal enhancement pattern was the dominate feature, seen in 9/14 cases (64%. Regarding enhancement kinetic curve, 21/29 (78% lesions showed suspicious malignant type kinetics. No significant difference was found in morphology (>.05, tumor size (P = 0.21, and kinetic characteristics (=.38 between non-high grade (I+II and high-grade (III pure DCIS.

  18. Evaluation of different magnetic resonance imaging contrast materials to be used as dummy markers in image-guided brachytherapy for gynecologic malignancies

    Directory of Open Access Journals (Sweden)

    Camila Pessoa Sales

    2016-06-01

    Full Text Available Abstract Objective: To identify a contrast material that could be used as a dummy marker for magnetic resonance imaging. Materials and Methods: Magnetic resonance images were acquired with six different catheter-filling materials-water, glucose 50%, saline, olive oil, glycerin, and copper sulfate (CuSO4 water solution (2.08 g/L-inserted into compatible computed tomography/magnetic resonance imaging ring applicators placed in a phantom made of gelatin and CuSO4. The best contrast media were tested in four patients with the applicators in place. Results: In T2-weighted sequences, the best contrast was achieved with the CuSO4-filled catheters, followed by saline- and glycerin-filled catheters, which presented poor visualization. In addition (also in T2-weighted sequences, CuSO4 presented better contrast when tested in the phantom than when tested in the patients, in which it provided some contrast but with poor identification of the first dwell position, mainly in the ring. Conclusion: We found CuSO4 to be the best solution for visualization of the applicator channels, mainly in T2-weighted images in vitro, although the materials tested presented low signal intensity in the images obtained in vivo, as well as poor precision in determining the first dwell position.

  19. Evaluation of different magnetic resonance imaging contrast materials to be used as dummy markers in image-guided brachytherapy for gynecologic malignancies*

    Science.gov (United States)

    Sales, Camila Pessoa; Carvalho, Heloisa de Andrade; Taverna, Khallil Chaim; Pastorello, Bruno Fraccini; Rubo, Rodrigo Augusto; Borgonovi, Arthur Felipe; Stuart, Silvia Radwanski; Rodrigues, Laura Natal

    2016-01-01

    Objective To identify a contrast material that could be used as a dummy marker for magnetic resonance imaging. Materials and Methods Magnetic resonance images were acquired with six different catheter-filling materials-water, glucose 50%, saline, olive oil, glycerin, and copper sulfate (CuSO4) water solution (2.08 g/L)-inserted into compatible computed tomography/magnetic resonance imaging ring applicators placed in a phantom made of gelatin and CuSO4. The best contrast media were tested in four patients with the applicators in place. Results In T2-weighted sequences, the best contrast was achieved with the CuSO4-filled catheters, followed by saline- and glycerin-filled catheters, which presented poor visualization. In addition (also in T2-weighted sequences), CuSO4 presented better contrast when tested in the phantom than when tested in the patients, in which it provided some contrast but with poor identification of the first dwell position, mainly in the ring. Conclusion We found CuSO4 to be the best solution for visualization of the applicator channels, mainly in T2-weighted images in vitro, although the materials tested presented low signal intensity in the images obtained in vivo, as well as poor precision in determining the first dwell position. PMID:27403016

  20. Parity decomposition theory of full wavefront aberration measurement using the intensity differences of aerial images in microlithography.

    Science.gov (United States)

    Yashiki, Satoshi

    2015-06-10

    The theory of full wavefront aberration measurements is developed using the intensity differences of aerial images, which are the projected images of one-dimensional measurement patterns consisting of single- or multibars. The key concept is the parity decomposition about the optical axis for two optical components: illumination pupil and wavefront aberration. An additional mathematical treatment, which is a perturbative approach with regard to aberration, is applied to the partially coherent imaging formula. The intensity difference of the two peaks has terms that are linear to the odd and even aberration with rigorously canceled squared aberration terms. The full wavefront aberration measurement is realized from simultaneous linear equations about the intensity difference. The validity of this approach is numerically confirmed under practical lithography conditions.

  1. Effects of different preprocessing algorithms on the prognostic value of breast tumour microscopic images.

    Science.gov (United States)

    Kolarević, D; Vujasinović, T; Kanjer, K; Milovanović, J; Todorović-Raković, N; Nikolić-Vukosavljević, D; Radulovic, M

    2017-09-21

    The purpose of this study was to improve the prognostic value of tumour histopathology image analysis methodology by image preprocessing. Key image qualities were modified including contrast, sharpness and brightness. The texture information was subsequently extracted from images of haematoxylin/eosin-stained tumour tissue sections by GLCM, monofractal and multifractal algorithms without any analytical limitation to predefined structures. Images were derived from patient groups with invasive breast carcinoma (BC, 93 patients) and inflammatory breast carcinoma (IBC, 51 patients). The prognostic performance was indeed significantly enhanced by preprocessing with the average AUCs of individual texture features improving from 0.68 ± 0.05 for original to 0.78 ± 0.01 for preprocessed images in the BC group and 0.75 ± 0.01 to 0.80 ± 0.02 in the IBC group. Image preprocessing also improved the prognostic independence of texture features as indicated by multivariate analysis. Surprisingly, the tonal histogram compression by the nonnormalisation preprocessing has prognostically outperformed the tested contrast normalisation algorithms. Generally, features without prognostic value showed higher susceptibility to prognostic enhancement by preprocessing whereas IDM texture feature was exceptionally susceptible. The obtained results are suggestive of the existence of distinct texture prognostic clues in the two examined types of breast cancer. The obtained enhancement of prognostic performance is essential for the anticipated clinical use of this method as a simple and cost-effective prognosticator of cancer outcome. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  2. Extending and applying active appearance models for automated, high precision segmentation in different image modalities

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Fisker, Rune; Ersbøll, Bjarne Kjær

    2001-01-01

    , an initialization scheme is designed thus making the usage of AAMs fully automated. Using these extensions it is demonstrated that AAMs can segment bone structures in radiographs, pork chops in perspective images and the left ventricle in cardiovascular magnetic resonance images in a robust, fast and accurate...... object class description, which can be employed to rapidly search images for new object instances. The proposed extensions concern enhanced shape representation, handling of homogeneous and heterogeneous textures, refinement optimization using Simulated Annealing and robust statistics. Finally...

  3. Coseismic displacements from SAR image offsets between different satellite sensors: Application to the 2001 Bhuj (India) earthquake

    KAUST Repository

    Wang, Teng

    2015-09-05

    Synthetic aperture radar (SAR) image offset tracking is increasingly being used for measuring ground displacements, e.g., due to earthquakes and landslide movement. However, this technique has been applied only to images acquired by the same or identical satellites. Here we propose a novel approach for determining offsets between images acquired by different satellite sensors, extending the usability of existing SAR image archives. The offsets are measured between two multiimage reflectivity maps obtained from different SAR data sets, which provide significantly better results than with single preevent and postevent images. Application to the 2001 Mw7.6 Bhuj earthquake reveals, for the first time, its near-field deformation using multiple preearthquake ERS and postearthquake Envisat images. The rupture model estimated from these cross-sensor offsets and teleseismic waveforms shows a compact fault slip pattern with fairly short rise times (<3 s) and a large stress drop (20 MPa), explaining the intense shaking observed in the earthquake.

  4. Judging the difference between attractiveness and health: does exposure to model images influence the judgments made by men and women?

    Directory of Open Access Journals (Sweden)

    Ian D Stephen

    Full Text Available Recent research has shown facial adiposity (apparent weight in the face to be a significant predictor of both attractiveness and health, thus making it an important determinant of mate selection. Studies looking at the relationship between attractiveness and health have shown that individuals differentiate between the two by preferring a lower weight for attractiveness than for health in female faces. However, these studies have either been correlational studies, or have investigated weight perceived from only the face. These differences have been discussed with regard to sociocultural factors such as pressure from parents, peers and also media, which has been seen to have the highest influence. While exposure to media images has been shown to influence women's own-body image, no study has yet directly tested the influence of these factors on people's preferred weight in other women's bodies. Here we examine how a short exposure to images of models influences men's and women's judgments of the most healthy looking and attractive BMI in Malaysian Chinese women's bodies by comparing differences in preferences (for attractiveness and health between groups exposed to images of models of varying attractiveness and body weight. Results indicated that participants preferred a lower weight for attractiveness than for health. Further, women's but not men's preferred BMI for attractiveness, but not health, was influenced by the type of media images to which they were exposed, suggesting that short term exposure to model images affect women's perceptions of attractiveness but not health.

  5. Towards pH-sensitive imaging of small animals with photon-counting difference diffuse fluorescence tomography

    Science.gov (United States)

    Li, Jiao; Wang, Xin; Yi, Xi; Zhang, Limin; Zhou, Zhongxing; Zhao, Huijuan; Gao, Feng

    2012-09-01

    The importance of cellular pH has been shown clearly in the study of cell activity, pathological feature, and drug metabolism. Monitoring pH changes of living cells and imaging the regions with abnormal pH-values, in vivo, could provide invaluable physiological and pathological information for the research of the cell biology, pharmacokinetics, diagnostics, and therapeutics of certain diseases such as cancer. Naturally, pH-sensitive fluorescence imaging of bulk tissues has been attracting great attentions from the realm of near infrared diffuse fluorescence tomography (DFT). Herein, the feasibility of quantifying pH-induced fluorescence changes in turbid medium is investigated using a continuous-wave difference-DFT technique that is based on the specifically designed computed tomography-analogous photon counting system and the Born normalized difference image reconstruction scheme. We have validated the methodology using two-dimensional imaging experiments on a small-animal-sized phantom, embedding an inclusion with varying pH-values. The results show that the proposed approach can accurately localize the target with a quantitative resolution to pH-sensitive variation of the fluorescent yield, and might provide a promising alternative method of pH-sensitive fluorescence imaging in addition to the fluorescence-lifetime imaging.

  6. Judging the difference between attractiveness and health: does exposure to model images influence the judgments made by men and women?

    Science.gov (United States)

    Stephen, Ian D; Perera, A Treshi-Marie

    2014-01-01

    Recent research has shown facial adiposity (apparent weight in the face) to be a significant predictor of both attractiveness and health, thus making it an important determinant of mate selection. Studies looking at the relationship between attractiveness and health have shown that individuals differentiate between the two by preferring a lower weight for attractiveness than for health in female faces. However, these studies have either been correlational studies, or have investigated weight perceived from only the face. These differences have been discussed with regard to sociocultural factors such as pressure from parents, peers and also media, which has been seen to have the highest influence. While exposure to media images has been shown to influence women's own-body image, no study has yet directly tested the influence of these factors on people's preferred weight in other women's bodies. Here we examine how a short exposure to images of models influences men's and women's judgments of the most healthy looking and attractive BMI in Malaysian Chinese women's bodies by comparing differences in preferences (for attractiveness and health) between groups exposed to images of models of varying attractiveness and body weight. Results indicated that participants preferred a lower weight for attractiveness than for health. Further, women's but not men's preferred BMI for attractiveness, but not health, was influenced by the type of media images to which they were exposed, suggesting that short term exposure to model images affect women's perceptions of attractiveness but not health.

  7. Do Basic Psychomotor Skills Transfer Between Different Image-based Procedures?

    NARCIS (Netherlands)

    Buzink, S.N.; Goossens, R.H.M.; Schoon, E.J.; De Ridder, H.; Jakimowicz, J.J.

    2010-01-01

    Background - Surgical techniques that draw from multiple types of image-based procedures (IBP) are increasing, such as Natural Orifice Transluminal Endoscopic Surgery, fusing laparoscopy and flexible endoscopy. However, little is known about the relation between psychomotor skills for performing

  8. A study on the effect of different image centres on stereo triangulation accuracy

    CSIR Research Space (South Africa)

    De Villiers, J

    2015-11-01

    Full Text Available This paper evaluates the effect of mixing the distortion centre, principal point and arithmetic image centre on the distortion correction, focal length determination and resulting real-world stereo vision triangulation. A robotic arm is used...

  9. MR imaging of capitellar ossification: a study in children of different ages

    Energy Technology Data Exchange (ETDEWEB)

    Fader, Lauren M. [University of Cincinnati College of Medicine, Cincinnati, OH (United States); Laor, Tal [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Eismann, Emily A.; Cornwall, Roger; Little, Kevin J. [Cincinnati Children' s Hospital Medical Center, Division of Orthopaedic Surgery, Cincinnati, OH (United States)

    2014-08-15

    The capitellar ossification center is used routinely to evaluate elbow alignment on radiography. However, whether capitellar ossification is central and concentric to support this practice is unknown. To define the pattern of capitellar ossification at different ages of childhood. This HIPAA-compliant study was IRB approved. MR imaging examinations from 81 children (ages 1-13 years, at least 3 boys and 3 girls in each age group) were included. We determined the center points of the ossified capitellum and the cartilaginous capitellum on the sagittal and coronal sequences that best showed differentiation between cartilage and bone. Percentage offset of the center of the ossified capitellum from the center of the cartilaginous capitellum was calculated in anterior-posterior, proximal-distal and medial-lateral dimensions, and compared across age groups and between genders. Linear regressions were used to ascertain the effect of age on percentage offset for all patients and for each gender. Capitellar ossification begins eccentrically with sagittal anterior proximal offset and coronal medial offset. With age, ossification proceeds posteriorly, distally and laterally. Percentage offset gradually diminishes with age. The ossified capitellum centralizes in the sagittal plane by 12-13 years. In the coronal plane, the capitellum ossifies medially beyond the proximal radioulnar joint and remains eccentric at 12-13 years. Centralization in boys lags in the anterior-posterior dimension. Capitellar ossification is an eccentric process, with lag in anterior-posterior centralization in boys. Medial offset persists at 12-13 years. Recognition of this eccentric ossification may allow for more accurate assessment of elbow alignment on radiographs, especially in younger children. (orig.)

  10. Double-Difference Earthquake Locations Using imaging Magma Under St. Helens (iMUSH) Data

    Science.gov (United States)

    Williams, M. C. B.; Ulberg, C. W.; Creager, K. C.

    2015-12-01

    The imaging Magma Under St. Helens (iMUSH) project deployed a magnetotelluric survey, high-resolution active-source experiment, two-year passive-source experiment, and gathered geochemical-petrological data to better understand the magmatic architecture of Mount St. Helens. A primary goal of the passive source experiment is to create 3-D P-wave and S-wave velocity models under the volcano from the surface to the slab. We use hypoDD, a double-difference algorithm, to gain high-precision relative earthquake locations for several hundred events within tens of kilometers of the Mount St. Helens crater. We use data from the first half (2014 June- 2015 July) of the two-year passive-source component of the iMUSH array recording six hundred useable earthquakes with a high-event density near the volcanic crater. The array includes seventy evenly-spaced broadband seismometers continuously sampling at 50 Hz within a 50 km radius of Mount St. Helens, and is augmented by dozens of permanent network stations. Precise relative earthquake locations are determined for spatially clustered hypocenters using a combination of hand picked P-wave arrivals and high-precision relative times determined by cross correlation of waveforms recorded at a common station for event pairs using a 1-D velocity structure. These high-quality relative times will be used to help constrain seismic tomography models as well. We will interrupt earthquake clusters in the context of emerging 3-D wave-speed models from the active-source and passive-source observations. We are examining the relationship between hypocentral locations and regions of partial melt, as well as the relationship between hypocentral locations and the NNW-SSE trending Saint Helens seismic Zone.

  11. MR imaging of capitellar ossification: a study in children of different ages.

    Science.gov (United States)

    Fader, Lauren M; Laor, Tal; Eismann, Emily A; Cornwall, Roger; Little, Kevin J

    2014-08-01

    The capitellar ossification center is used routinely to evaluate elbow alignment on radiography. However, whether capitellar ossification is central and concentric to support this practice is unknown. To define the pattern of capitellar ossification at different ages of childhood. This HIPAA-compliant study was IRB approved. MR imaging examinations from 81 children (ages 1-13 years, at least 3 boys and 3 girls in each age group) were included. We determined the center points of the ossified capitellum and the cartilaginous capitellum on the sagittal and coronal sequences that best showed differentiation between cartilage and bone. Percentage offset of the center of the ossified capitellum from the center of the cartilaginous capitellum was calculated in anterior-posterior, proximal-distal and medial-lateral dimensions, and compared across age groups and between genders. Linear regressions were used to ascertain the effect of age on percentage offset for all patients and for each gender. Capitellar ossification begins eccentrically with sagittal anterior proximal offset and coronal medial offset. With age, ossification proceeds posteriorly, distally and laterally. Percentage offset gradually diminishes with age. The ossified capitellum centralizes in the sagittal plane by 12-13 years. In the coronal plane, the capitellum ossifies medially beyond the proximal radioulnar joint and remains eccentric at 12-13 years. Centralization in boys lags in the anterior-posterior dimension. Capitellar ossification is an eccentric process, with lag in anterior-posterior centralization in boys. Medial offset persists at 12-13 years. Recognition of this eccentric ossification may allow for more accurate assessment of elbow alignment on radiographs, especially in younger children.

  12. Gender differences in body image and preferences for an ideal silhouette among Brazilian undergraduates.

    Science.gov (United States)

    Laus, Maria Fernanda; Costa, Telma Maria Braga; Almeida, Sebastião Sousa

    2015-12-01

    The aim of this study was to investigate gender differences in the accuracy of body size estimation and body dissatisfaction among Brazilian undergraduates and their relationships with perceptions of the ideal body silhouettes that would be selected by same-gender and opposite-gender peers. A total of 159 undergraduates (79 males) from a public University in Ribeirao Preto, Sao Paulo, Brazil, participated in the study. They completed a Figure Rating Scale and indicated the figure that best describes the size of their own body (actual), their desired body, the body they judged would be ideal to same-gender peers, and the body they judged would be ideal to opposite-gender peers. The results showed that women were less precise in estimating their actual size and more dissatisfied. The mean Body Mass Index (BMI) that was selected as “current” by women was significantly higher than their desired and ideal BMIs, whereas the mean BMIs that were selected by men were practically the same. Men and women selected ideal silhouettes for their own gender that were the same as those that were selected as ideal by the opposite gender. The mean BMIs that were actually chosen by men and women as desired and ideal were closer to the upper end of normal weight and lower end of overweight, respectively. Such results contradict what has been assumed to be a normative characteristic of men and women in several countries, raising some doubts regarding the role of beliefs about judgments of the opposite gender in the development of body image disturbances.

  13. A Weighted Difference of Anisotropic and Isotropic Total Variation Model for Image Processing

    Science.gov (United States)

    2014-09-01

    the perspective of compressive sensing (CS) [3, 12], which is to reconstruct a signal from an under-determined system provided that the signal is...deconvolution using closed-form thresholding formulas of lq(q=1/2,2/3) regularization, J. Vis. Comun . Image Represent., 24 (2013), pp. 31–41. [5] A...Bregman iteration, Inter- national Journal of Imaging Systems and Technology, 15 (2005), pp. 74–83. [17] Q. He and J. Xin, A randomly perturbed INFOMAX

  14. Different Facets of Body Image Disturbance in Binge Eating Disorder: A Review

    Science.gov (United States)

    Lewer, Merle; Bauer, Anika

    2017-01-01

    The goal of the present review is to give an overview of the current findings on various facets of body image disturbance in Binge Eating Disorder such as body dissatisfaction, overconcern with weight and shape, body-related checking and avoidance behavior, misperception of body size, and body-related cognitive bias. In addition, treatments for a disturbed body image in BED and evidence of body image disturbance in youth with binge eating are reviewed. The results show that a disturbed body image in BED is present in the form of overconcern with weight and shape. Furthermore, there are hints that body dissatisfaction, as well as body-related checking and avoidance behavior, are also impaired. Research concerning misperception of body size in BED has been neglected so far, but first findings show that individuals with BED rate their own body shape rather accurately. Furthermore, there are first hints that body-related cognitive biases are present in individuals with BED. Moreover, in children and adolescents, there are first hints that body dissatisfaction, as well as shape and weight concerns, seem to be associated with loss of control and binge eating. Treatments aimed directly at the convertibility of a disturbed body image in BED have revealed encouraging outcomes. In conclusion, body image disturbance seems to occur in BED, and first studies show that it can be treated effectively. PMID:29182531

  15. Different Facets of Body Image Disturbance in Binge Eating Disorder: A Review

    Directory of Open Access Journals (Sweden)

    Merle Lewer

    2017-11-01

    Full Text Available The goal of the present review is to give an overview of the current findings on various facets of body image disturbance in Binge Eating Disorder such as body dissatisfaction, overconcern with weight and shape, body-related checking and avoidance behavior, misperception of body size, and body-related cognitive bias. In addition, treatments for a disturbed body image in BED and evidence of body image disturbance in youth with binge eating are reviewed. The results show that a disturbed body image in BED is present in the form of overconcern with weight and shape. Furthermore, there are hints that body dissatisfaction, as well as body-related checking and avoidance behavior, are also impaired. Research concerning misperception of body size in BED has been neglected so far, but first findings show that individuals with BED rate their own body shape rather accurately. Furthermore, there are first hints that body-related cognitive biases are present in individuals with BED. Moreover, in children and adolescents, there are first hints that body dissatisfaction, as well as shape and weight concerns, seem to be associated with loss of control and binge eating. Treatments aimed directly at the convertibility of a disturbed body image in BED have revealed encouraging outcomes. In conclusion, body image disturbance seems to occur in BED, and first studies show that it can be treated effectively.

  16. Different Facets of Body Image Disturbance in Binge Eating Disorder: A Review.

    Science.gov (United States)

    Lewer, Merle; Bauer, Anika; Hartmann, Andrea S; Vocks, Silja

    2017-11-28

    The goal of the present review is to give an overview of the current findings on various facets of body image disturbance in Binge Eating Disorder such as body dissatisfaction, overconcern with weight and shape, body-related checking and avoidance behavior, misperception of body size, and body-related cognitive bias. In addition, treatments for a disturbed body image in BED and evidence of body image disturbance in youth with binge eating are reviewed. The results show that a disturbed body image in BED is present in the form of overconcern with weight and shape. Furthermore, there are hints that body dissatisfaction, as well as body-related checking and avoidance behavior, are also impaired. Research concerning misperception of body size in BED has been neglected so far, but first findings show that individuals with BED rate their own body shape rather accurately. Furthermore, there are first hints that body-related cognitive biases are present in individuals with BED. Moreover, in children and adolescents, there are first hints that body dissatisfaction, as well as shape and weight concerns, seem to be associated with loss of control and binge eating. Treatments aimed directly at the convertibility of a disturbed body image in BED have revealed encouraging outcomes. In conclusion, body image disturbance seems to occur in BED, and first studies show that it can be treated effectively.

  17. Ocular MR imaging: evaluation of different coil setups in a phantom study.

    Science.gov (United States)

    Erb-Eigner, Katharina; Warmuth, Carsten; Taupitz, Matthias; Bertelmann, Eckart; Hamm, Bernd; Asbach, Patrick

    2013-01-01

    Small loop surface coils are generally recommended for ocular magnetic resonance (MR) imaging, but the optimal coil setup has not been systematically investigated. In this phantom study, we investigated which coil setup of those coils available for our MR imaging system provides the highest signal-to-noise ratio (SNR) in ocular MR imaging at 1.5 tesla. Using a phantom to simulate the eyeball and the orbital fat, we employed loop surface coils of 4- and 6-cm diameter and a multi-channel head coil to obtain images using a T1-weighted spin-echo sequence and then measured the SNR for each coil and coil combination. Use of the 6-cm loop coil alone yielded the highest mean SNR (27.5). Even in superficial regions (mesial and temporal), the SNR was higher using the 6-cm loop coil (33.6 and 45.5) than the 4-cm loop coil (28.0 and 33.8). Additional use of the head coil reduced the mean SNR to 10.4. This quantitative analysis suggests that use of a 6-cm loop surface coil offers the best results in ocular MR imaging. Combinations of loop coils or additional use of a head coil cannot be recommended because higher noise degrades image quality.

  18. FEATURE CAREER STRUCTURE OF THE IMAGE AT DIFFERENT STAGES OF PROFESSIONAL DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Pankratova Irina Anatolievna

    2016-12-01

    Full Text Available The paper describes research carried out in the framework of the study of representations of professional identity. The aim of this paper is to study the image of the career structure and its structural elements. The study was conducted on a sample of 635 people, among them - 388 women and girls and 247 boys and men. The empirical study was carried out on the basis of faculty «State and municipal management» (students of 1 and 5 courses and «training of civil servants», Russian. Career image includes three components: structural; informative and emotional evaluation. The content of the career image components changes depending on what stage of professional development the personality is. The structural component in the process of professional development varies from amorphous and ill-structured at the first stage of professional development to a clear and specific at the last stage of professional development. The career trajectory changes as follows: at the first, third and fourth stages of professional development the most characteristic is the graph of a career «vertical», and at the second stage it is «plateau». As to the content of career image we can note that the most common for all stages of career development is the dominance of financial goals. Emotional-evaluative component of the career image is maximally differentiated at the second stage of professional development, at all other stages the career image has a common neutral color.

  19. Reproducibility of serial peri-ictal single-photon emission tomography difference images in epilepsy patients undergoing surgical resection

    Energy Technology Data Exchange (ETDEWEB)

    Avery, R.A.; Studholme, C.; Stokking, R.; Morano, G.; Corsi, M.; Seibyl, J.P.; Zubal, I.G. [Dept. of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT (United States); Spencer, S.S. [Dept. of Neurology, Yale University School of Medicine, New Haven, CT (United States); Spencer, D.D. [Dept. of Neurosurgery, Yale University School of Medicine, New Haven, CT (United States)

    2000-01-01

    Peri-ictal single-photon emission tomography (SPET) difference images co-registered to magnetic resonance imaging (MRI) visualize regional cerebral blood flow (rCBF) changes and help localize the epileptogenic area in medically refractory epilepsy. Few reports have examined the reproducibility of SPET difference image results. Epilepsy patients having two peri-ictal and at least one interictal SPET scan who later underwent surgical resection were studied. Localization accuracy of peri-ictal SPET difference images results, interictal electroencephalography (EEG), and ictal EEG from the first (seizure 1) and second (seizure 2) seizure, as well as MRI and positron emission tomography (PET) findings, were compared using surgical resection site as the standard. Thirteen patients underwent surgical resection (11 temporal lobe and 2 extratemporal). SPET results from seizure 1 were localized to the surgical site in 12/13 (92%) patients, while SPET results from seizure 2 were localized in 13/13 (100%) patients. All other modalities were less accurate than the SPET results [interictal EEG - seizure 1 6/13 (46%); ictal EEG - seizure 1 5/13 (38%); interictal intracranial EEG - seizure 2 4/9 (44%); ictal intracranial EEG - seizure 2 results 8/9 (89%); MRI 6/13 (46%); PET 9/13 (69%)]. SPET results were reproducible in 12/13 (92%) patients. SPET difference images calculated from two independent peri-ictal scans appear to be reproducible and accurately localize the epileptogenic area. While SPET difference images visualize many areas of rCBF change, the quantification of these results along with consideration of injection time improves the diagnostic interpretation of the results. (orig.)

  20. Demographic differences in and correlates of perceived body image discrepancy among urban adolescent girls: a cross-sectional study.

    Science.gov (United States)

    Robbins, Lorraine B; Ling, Jiying; Resnicow, Kenneth

    2017-12-06

    Understanding factors related to girls' body image discrepancy, which is the difference between self-perceived current or actual and ideal body size, is important for addressing body-related issues and preventing adverse sequelae. Two aims were to: 1) examine demographic differences in body image discrepancy; and 2) determine the association of body image discrepancy with weight status, percent body fat, physical activity, sedentary behavior, and cardiovascular (CV) fitness among young adolescent girls. The cross-sectional study included a secondary analysis of baseline data from a group randomized controlled trial including 1519 5th-8th grade girls in 24 U.S. schools. Girls completed physical activity and sedentary behavior surveys. To indicate perceived current/actual and ideal body image, girls selected from nine body figures the one that represented how they look now and another showing how they want to look. Girls wore accelerometers measuring physical activity. Height, weight, and percent body fat were assessed. The Progressive Aerobic CV Endurance Run was used to estimate CV fitness. Independent t-test, one- and two-way ANOVA, correlational analyses, and hierarchical linear regressions were performed. The majority (67.5%; n = 1023) chose a smaller ideal than current/actual figure. White girls had higher body image discrepancy than Black girls (p = .035). Body image discrepancy increased with increasing weight status (F 3,1506  = 171.32, p < .001). Moderate-to-vigorous physical activity (MVPA) and vigorous physical activity were negatively correlated with body image discrepancy (r = -.10, p < .001; r = -.14, p < .001, respectively), but correlations were not significant after adjusting for race and body mass index (BMI), respectively. Body image discrepancy was moderately correlated with CV fitness (r = -.55, p < .001). After adjusting for demographics, percent body fat, but not CV fitness or MVPA, influenced body

  1. MR imaging findings in 56 patients with Wernicke encephalopathy: nonalcoholics may differ from alcoholics.

    Science.gov (United States)

    Zuccoli, G; Santa Cruz, D; Bertolini, M; Rovira, A; Gallucci, M; Carollo, C; Pipitone, N

    2009-01-01

    Wernicke encephalopathy (WE) is a severe neurologic disorder resulting from dietary vitamin B(1) deficiency. This study was undertaken to analyze and compare MR imaging findings and neurologic manifestations at clinical presentations of patients with WE with and without a history of alcohol abuse. WE patients were identified using diagnostic neurologic data bases. Fifty-six patients (29 females, 27 males) diagnosed between 1999 and 2008 with WE who improved within 1 month from the onset of thiamine administration were included in the analysis. Patients' records were reviewed for clinical manifestations and imaging studies' findings. MR imaging was performed in the acute phase of the disease at a field strength of 1T (16 patients) and 1.5T (40 patients). All MR images were of acceptable to good quality and were retrospectively reviewed. We compared imaging findings and clinical presentation in the alcoholic (AL) group versus the non-alcoholic (NA) group using the 2-tailed Fisher exact test and the Phi coefficient as appropriate. Forty-three percent of the patients were in the AL group, whereas 57% were in the NA group. Eighty-nine percent showed changes in consciousness, 75% had ocular manifestations, and 54% had ataxia. On MR imaging, 80% of the patients had evidence of symmetric lesions in the medial thalami and in the periventricular region of the third ventricle; 59%, in the periaqueductal area; 45%, in the mamillary bodies; 36%, in the tectal plate; and 7%, in the periventricular gray matter located anteriorly to the fourth ventricle. Signal-intensity alterations in areas considered atypical for the disease were noted only in the NA group and always in association with the typical findings. Contrast enhancement of the thalamus and mamillary bodies was significantly associated with alcohol abuse. Contrast enhancement in the mamillary bodies and thalamus is a typical finding of the disease in AL patients. Atypical MR imaging findings characterize NA patients.

  2. Hyperspectral Imaging in Tandem with R Statistics and Image Processing for Detection and Visualization of pH in Japanese Big Sausages under Different Storage Conditions.

    Science.gov (United States)

    Feng, Chao-Hui; Makino, Yoshio; Yoshimura, Masatoshi; Thuyet, Dang Quoc; García-Martín, Juan Francisco

    2017-12-26

    The potential of hyperspectral imaging with wavelengths of 380 to 1000 nm was used to determine the pH of cooked sausages after different storage conditions (4 °C for 1 d, 35 °C for 1, 3, and 5 d). The mean spectra of the sausages were extracted from the hyperspectral images and partial least squares regression (PLSR) model was developed to relate spectral profiles with the pH of the cooked sausages. Eleven important wavelengths were selected based on the regression coefficient values. The PLSR model established using the optimal wavelengths showed good precision being the prediction coefficient of determination (Rp2 ) 0.909 and the root mean square error of prediction 0.035. The prediction map for illustrating pH indices in sausages was for the first time developed by R statistics. The overall results suggested that hyperspectral imaging combined with PLSR and R statistics are capable to quantify and visualize the sausages pH evolution under different storage conditions. In this paper, hyperspectral imaging is for the first time used to detect pH in cooked sausages using R statistics, which provides another useful information for the researchers who do not have the access to Matlab. Eleven optimal wavelengths were successfully selected, which were used for simplifying the PLSR model established based on the full wavelengths. This simplified model achieved a high Rp2 (0.909) and a low root mean square error of prediction (0.035), which can be useful for the design of multispectral imaging systems. © 2017 Institute of Food Technologists®.

  3. Differences between generalized q-sampling imaging and diffusion tensor imaging in the preoperative visualization of the nerve fiber tracts within peritumoral edema in brain.

    Science.gov (United States)

    Zhang, Hongliang; Wang, Yong; Lu, Tao; Qiu, Bo; Tang, Yanqing; Ou, Shaowu; Tie, Xinxin; Sun, Chuanqi; Xu, Ke; Wang, Yibao

    2013-12-01

    Diffusion tensor imaging (DTI) tractography enables the in vivo visualization of white matter tracts inside normal brain tissue, which provides the neurosurgeon important information to plan tumor resections. However, DTI is associated with restrictions in the resolution of crossing fibers in the vicinity of the tumor or in edema. We find that generalized q-sampling imaging (GQI) can overcome these difficulties and is advantageous over DTI for the tractography of the fiber bundle in peritumoral edema. To demonstrate the differences between GQI and DTI in the preoperative mapping of fiber tractography in peritumoral edema of cerebral tumors, and discuss the clinical application of GQI in neurosurgical planning. Five patients with brain tumors underwent 3-T magnetic resonance imaging scans, and the data were reconstructed by DTI and GQI. We adjusted the parameters and compared the differences between DTI and GQI in visualizing the fiber tracts in the peritumoral edema of cerebral tumors. GQI and DTI showed substantial differences in displaying the nerve fibers in the edema surrounding the tumor. The GQI tractography method could fully display existing intact fibers in the edema, whereas the fiber tracts in edema displayed by DTI tractography were incomplete, missing, or ruptured. GQI can visualize the tracts in the peritumoral edema of cerebral tumors better than DTI. Although GQI has many limitations, its future in the preoperative guidance of brain tumor lesions is promising.

  4. Six iterative reconstruction algorithms in brain CT: a phantom study on image quality at different radiation dose levels

    Science.gov (United States)

    Olsson, M-L; Siemund, R; Stålhammar, F; Björkman-Burtscher, I M; Söderberg, M

    2013-01-01

    Objective: To evaluate the image quality produced by six different iterative reconstruction (IR) algorithms in four CT systems in the setting of brain CT, using different radiation dose levels and iterative image optimisation levels. Methods: An image quality phantom, supplied with a bone mimicking annulus, was examined using four CT systems from different vendors and four radiation dose levels. Acquisitions were reconstructed using conventional filtered back-projection (FBP), three levels of statistical IR and, when available, a model-based IR algorithm. The evaluated image quality parameters were CT numbers, uniformity, noise, noise-power spectra, low-contrast resolution and spatial resolution. Results: Compared with FBP, noise reduction was achieved by all six IR algorithms at all radiation dose levels, with further improvement seen at higher IR levels. Noise-power spectra revealed changes in noise distribution relative to the FBP for most statistical IR algorithms, especially the two model-based IR algorithms. Compared with FBP, variable degrees of improvements were seen in both objective and subjective low-contrast resolutions for all IR algorithms. Spatial resolution was improved with both model-based IR algorithms and one of the statistical IR algorithms. Conclusion: The four statistical IR algorithms evaluated in the study all improved the general image quality compared with FBP, with improvement seen for most or all evaluated quality criteria. Further improvement was achieved with one of the model-based IR algorithms. Advances in knowledge: The six evaluated IR algorithms all improve the image quality in brain CT but show different strengths and weaknesses. PMID:24049128

  5. Influence of patient position and other inherent factors on image quality in two different cone beam computed tomography (CBCT devices

    Directory of Open Access Journals (Sweden)

    Ninita Lindfors

    Full Text Available Objectives: The aim of this in vitro study was to evaluate how a deviation from the horizontal plane, affects the image quality in two different CBCT-devices. Methods: A phantom head SK150 (RANDO, The Phantom Laboratory, Salem, NY, USA was examined in two CBCT-units: Accuitomo 80 and Veraviewepocs 3D R100 (J. Morita Mfg. Corp. Kyoto, Japan. The phantom head was placed with the hard palate parallel to the horizontal plane and tilted 20 ° backwards. Exposures were performed with different field of views (FOVs, voxel sizes, slice thicknesses and exposure settings. Effective dose was calculated using PCXMC 2.0 (STUK, Helsinki, Finland. Image quality was assessed using contrast-to-noise-ratio (CNR. Region of interest (ROI was set at three different levels of the mandibular bone and soft tissue, uni- and bilaterally in small and large FOVs, respectively. CNR values were calculated by CT-value and standard deviation for each ROI. Factor analysis was used to analyze the material. Results: Tilting the phantom head backwards rendered significantly higher mean CNR values regardless of FOV. The effective dose was lower in small than in large FOVs and varied to a larger extent between CBCT-devices in large FOVs. Conclusions: Head position can affect the image quality. Tilting the head backward improved image quality in the mandibular region. However, if influenced by other variables e.g. motion artifacts in a clinical situation, remains to be further investigated. Advances in knowledge: Image quality assessed using CNR values to investigate the influence of different patient positions and FOVs. Keywords: Image quality, CBCT, Radiation dose, Patient position, FOV

  6. Dental fluorosis in populations from Chiang Mai, Thailand with different fluoride exposures - paper 2: the ability of fluorescence imaging to detect differences in fluorosis prevalence and severity for different fluoride intakes from water.

    Science.gov (United States)

    McGrady, Michael G; Ellwood, Roger P; Srisilapanan, Patcharawan; Korwanich, Narumanas; Taylor, Andrew; Goodwin, Michaela; Pretty, Iain A

    2012-08-21

    To assess the ability of fluorescence imaging to detect a dose response relationship between fluorosis severity and different levels of fluoride in water supplies compared to remote photographic scoring in selected populations participating in an observational, epidemiological survey in Chiang Mai, Thailand. Subjects were male and female lifetime residents aged 8-13 years. For each child the fluoride content of cooking water samples (CWS) was assessed to create categorical intervals of water fluoride concentration. Fluorescence images were taken of the maxillary central incisors and analyzed for dental fluorosis using two different software techniques. Output metrics for the fluorescence imaging techniques were compared to TF scores from blinded photographic scores obtained from the survey. Data from 553 subjects were available. Both software analysis techniques demonstrated significant correlations with the photographic scores. The metrics for area effected by fluorosis and the overall fluorescence loss had the strongest association with the photographic TF score (Spearman's rho 0.664 and 0.652 respectively). Both software techniques performed well for comparison of repeat fluorescence images with ICC values of 0.95 and 0.85 respectively. This study supports the potential use of fluorescence imaging for the objective quantification of dental fluorosis. Fluorescence imaging was able to discriminate between populations with different fluoride exposures on a comparable level to remote photographic scoring with acceptable levels of repeatability.

  7. Extraction of Blood Vessels in Retinal Images Using Four Different Techniques

    Directory of Open Access Journals (Sweden)

    Asloob Ahmad Mudassar

    2013-01-01

    Full Text Available A variety of blood vessel extraction (BVE techniques exist in the literature, but they do not always lead to acceptable solutions especially in the presence of anomalies where the reported work is limited. Four techniques are presented for BVE: (1 BVE using Image Line Cross-Sections (ILCS, (2 BVE using Edge Enhancement and Edge Detection (EEED, (3 BVE using Modified Matched Filtering (MMF, and (4 BVE using Continuation Algorithm (CA. These four techniques have been designed especially for abnormal retinal images containing low vessel contrasts, drusen, exudates, and other artifacts. The four techniques were applied to 30 abnormal retinal images, and the success rate was found to be (95 to 99% for CA, (88–91% for EEED, (80–85% for MMF, and (74–78% for ILCS. Application of these four techniques to 105 normal retinal images gave improved results: (99-100% for CA, (96–98% for EEED, (94-95% for MMF, and (88–93% for ILCS. Investigations revealed that the four techniques in the order of increasing performance could be arranged as ILCS, MMF, EEED, and CA. Here we demonstrate these four techniques for abnormal retinal images only. ILCS, EEED, and CA are novel additions whereas MMF is an improved and modified version of an existing matched filtering technique. CA is a promising technique.

  8. Modeling of realistic raw data for image reconstruction: quantifying scattering noise in different CT geometries

    Science.gov (United States)

    Schlattl, H.; Tischenko, O.; Hoeschen, C.

    2006-03-01

    An important step in assessing the quality of an image reconstruction algorithm is the simulation of the medical imaging process. For that purpose, the patient's anatomical structure is substituted in general by more or less simple geometrical objects, as, e.g., the Shepp-Logan phantom. Furthermore, the attenuation of the human body and thus the resulting detector image (e.g., the sinogram in CT) is often computed by integrating the attenuation coefficient along various rays without considering the contribution of scattered photons in the detector signal. We therefore decided to improve the simulation by using an existing Monte Carlo code (EGSnrc) to model the transport of numerous photons from the x-ray tube through the body to the detector. The deflection of photons and creation of secondary particles in scattering events occurs naturally in this program, but can also be avoided artificially. Besides the improved simulation of the irradiation process, this allows us to quantify the amount of scattered radiation in the detector image. The patient is represented by a so-called voxel phantom, which is based on tomographic image data of a real person, adopted to represent the ICRP Reference Man. Our improved modeling process is being applied to determine the amount of scatter radiation in helical multi-slice CT of the thorax compared to a planned circular CT with large flat panel detectors. The new reconstruction algorithm OPED (orthogonal polynomial expansion on disc), developed at GSF and the University of Oregon, might reduce the scatter radiation considerably.

  9. Classifying Dementia Using Local Binary Patterns from Different Regions in Magnetic Resonance Images

    Directory of Open Access Journals (Sweden)

    Ketil Oppedal

    2015-01-01

    Full Text Available Dementia is an evolving challenge in society, and no disease-modifying treatment exists. Diagnosis can be demanding and MR imaging may aid as a noninvasive method to increase prediction accuracy. We explored the use of 2D local binary pattern (LBP extracted from FLAIR and T1 MR images of the brain combined with a Random Forest classifier in an attempt to discern patients with Alzheimer's disease (AD, Lewy body dementia (LBD, and normal controls (NC. Analysis was conducted in areas with white matter lesions (WML and all of white matter (WM. Results from 10-fold nested cross validation are reported as mean accuracy, precision, and recall with standard deviation in brackets. The best result we achieved was in the two-class problem NC versus AD + LBD with total accuracy of 0.98 (0.04. In the three-class problem AD versus LBD versus NC and the two-class problem AD versus LBD, we achieved 0.87 (0.08 and 0.74 (0.16, respectively. The performance using 3DT1 images was notably better than when using FLAIR images. The results from the WM region gave similar results as in the WML region. Our study demonstrates that LBP texture analysis in brain MR images can be successfully used for computer based dementia diagnosis.

  10. Different diagnostic values of imaging parameters to predict pseudoprogression in glioblastoma subgroups stratified by MGMT promoter methylation

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Ra Gyoung [Catholic Kwandong University International St. Mary' s Hospital, Department of Radiology, Catholic Kwandong University College of Medicine, Incheon (Korea, Republic of); Kim, Ho Sung; Shim, Woo Hyun; Kim, Sang Joon [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Paik, Wooyul [Dankook Unversity Hospital, Department of Radiology, Cheonan-si, Chungcheongnam-do (Korea, Republic of); Kim, Jeong Hoon [University of Ulsan College of Medicine, Asan Medical Center, Department of Neurosurgery, Seoul (Korea, Republic of)

    2017-01-15

    The aim of this study was to determine whether diffusion and perfusion imaging parameters demonstrate different diagnostic values for predicting pseudoprogression between glioblastoma subgroups stratified by O{sup 6}-mythylguanine-DNA methyltransferase (MGMT) promoter methylation status. We enrolled seventy-five glioblastoma patients that had presented with enlarged contrast-enhanced lesions on magnetic resonance imaging (MRI) one month after completing concurrent chemoradiotherapy and undergoing MGMT promoter methylation testing. The imaging parameters included 10 or 90 % histogram cutoffs of apparent diffusion coefficient (ADC10), normalized cerebral blood volume (nCBV90), and initial area under the time signal-intensity curve (IAUC90). The results of the areas under the receiver operating characteristic curve (AUCs) with cross-validation were compared between MGMT methylation and unmethylation groups. MR imaging parameters demonstrated a trend toward higher accuracy in the MGMT promoter methylation group than in the unmethylation group (cross-validated AUCs = 0.70-0.95 and 0.56-0.87, respectively). The combination of MGMT methylation status with imaging parameters improved the AUCs from 0.70 to 0.75-0.90 for both readers in comparison with MGMT methylation status alone. The probability of pseudoprogression was highest (95.7 %) when nCBV90 was below 4.02 in the MGMT promoter methylation group. MR imaging parameters could be stronger predictors of pseudoprogression in glioblastoma patients with the methylated MGMT promoter than in patients with the unmethylated MGMT promoter. (orig.)

  11. Comparison between Different Intensity Normalization Methods in 123I-Ioflupane Imaging for the Automatic Detection of Parkinsonism.

    Directory of Open Access Journals (Sweden)

    A Brahim

    Full Text Available Intensity normalization is an important pre-processing step in the study and analysis of DaTSCAN SPECT imaging. As most automatic supervised image segmentation and classification methods base their assumptions regarding the intensity distributions on a standardized intensity range, intensity normalization takes on a very significant role. In this work, a comparison between different novel intensity normalization methods is presented. These proposed methodologies are based on Gaussian Mixture Model (GMM image filtering and mean-squared error (MSE optimization. The GMM-based image filtering method is achieved according to a probability threshold that removes the clusters whose likelihood are negligible in the non-specific regions. The MSE optimization method consists of a linear transformation that is obtained by minimizing the MSE in the non-specific region between the intensity normalized image and the template. The proposed intensity normalization methods are compared to: i a standard approach based on the specific-to-non-specific binding ratio that is widely used, and ii a linear approach based on the α-stable distribution. This comparison is performed on a DaTSCAN image database comprising analysis and classification stages for the development of a computer aided diagnosis (CAD system for Parkinsonian syndrome (PS detection. In addition, these proposed methods correct spatially varying artifacts that modulate the intensity of the images. Finally, using the leave-one-out cross-validation technique over these two approaches, the system achieves results up to a 92.91% of accuracy, 94.64% of sensitivity and 92.65 % of specificity, outperforming previous approaches based on a standard and a linear approach, which are used as a reference. The use of advanced intensity normalization techniques, such as the GMM-based image filtering and the MSE optimization improves the diagnosis of PS.

  12. Total Variation Regularization Algorithms for Images Corrupted with Different Noise Models: A Review

    Directory of Open Access Journals (Sweden)

    Paul Rodríguez

    2013-01-01

    Full Text Available Total Variation (TV regularization has evolved from an image denoising method for images corrupted with Gaussian noise into a more general technique for inverse problems such as deblurring, blind deconvolution, and inpainting, which also encompasses the Impulse, Poisson, Speckle, and mixed noise models. This paper focuses on giving a summary of the most relevant TV numerical algorithms for solving the restoration problem for grayscale/color images corrupted with several noise models, that is, Gaussian, Salt & Pepper, Poisson, and Speckle (Gamma noise models as well as for the mixed noise scenarios, such the mixed Gaussian and impulse model. We also include the description of the maximum a posteriori (MAP estimator for each model as well as a summary of general optimization procedures that are typically used to solve the TV problem.

  13. Differentiating between Alzheimer Disease Patients and Controls with Phase-difference-enhanced Imaging at 3T: A Feasibility Study.

    Science.gov (United States)

    Tateishi, Machiko; Kitajima, Mika; Hirai, Toshinori; Yoneda, Tetsuya; Hashimoto, Mamoru; Kurehana, Nan; Uetani, Hiroyuki; Fukuhara, Ryuji; Azuma, Minako; Yamashita, Yasuyuki

    2018-01-15

    To test the feasibility of the phase difference enhanced (PADRE) imaging for differentiation between Alzheimer disease (AD) patients and control subjects on 3T MR imaging. Fifteen patients with AD and 10 age-matched control subjects underwent two-dimensional fast field echo imaging to obtain PADRE images on a 3T MR scanner. A double Gaussian distribution model was used to determine the threshold phase value for differentiation between the physiologic and non-physiologic iron in the cerebral cortices, and PADRE images were processed with the threshold. Using a 4-point grading system, two readers independently assessed the signal of the four cerebral cortices on PADRE images: the cuneus, precuneus, superior frontal gyrus, and superior temporal gyrus. The difference in the signals in each cortex between the AD patients and age-matched control subjects was determined by using Mann-Whitney U test. Inter-rater reliability was determined by Kappa analysis. We also evaluated the correlation between Mini-Mental State Examination (MMSE) score and the hypointense grade, and between disease duration and the hypointense grade using the Spearman rank correlation test. The threshold phase value for differentiation between the physiologic and non-physiologic iron was -4.6% π (radian). The mean grades of the cuneus, precuneus, and superior temporal gyrus were significantly higher for the AD patients than for the control subjects (P = 0.002). Excellent inter-rater reliability was seen in the precuneus (kappa = 0.93), superior temporal gyrus (kappa = 0.94), and superior frontal gyrus (kappa = 0.93); good inter-rater reliability was observed in the cuneus (kappa = 0.75). We found a statistical correlation between MMSE score and the hypointense grade in superior temporal gyrus (STG) (P = 0.008), and no correlation between disease duration and the hypointense grade in any gyrus. Our results suggest the feasibility of PADRE imaging at 3T for differentiation between AD patients and

  14. Automatic segmentation of different-sized leukoaraiosis regions in brain MR images

    Science.gov (United States)

    Uchiyama, Yoshikazu; Kunieda, Takuya; Hara, Takeshi; Fujita, Hiroshi; Ando, Hiromichi; Yamakawa, Hiroyasu; Asano, Takahiko; Kato, Hiroki; Iwama, Toru; Kanematsu, Masayuki; Hoshi, Hiroaki

    2008-03-01

    Cerebrovascular diseases are the third leading cause of death in Japan. Therefore, a screening system for the early detection of asymptomatic brain diseases is widely used. In this screening system, leukoaraiosis is often detected in magnetic resonance (MR) images. The quantitative analysis of leukoaraiosis is important because its presence and extension is associated with an increased risk of severe stroke. However, thus far, the diagnosis of leukoaraiosis has generally been limited to subjective judgments by radiologists. Therefore, the purpose of this study was to develop a computerized method for the segmentation of leukoaraiosis, and provide an objective measurement of the lesion volume. Our database comprised of T1- and T2-weighted images obtained from 73 patients. The locations of leukoaraiosis regions were determined by an experienced neuroradiologist. We first segment cerebral parenchymal regions in T1-weighted images by using a region growing technique. For determining the initial candidate regions for leukoaraiosis, the k-means clustering of pixel values in the T1- and T2-weighted images was applied to the segmented cerebral region. For the elimination of false positives (FPs), we determined features such as the location, size, and circularity from each of the initial candidates. Finally, rule-based schemes and a quadratic discriminant analysis with these features were employed for distinguishing between the leukoaraiosis regions and the FPs. The results indicated that the sensitivity for the detection of leukoaraiosis was 100% with 5.84 FPs per image. Our computerized scheme can be useful in assisting radiologists for the quantitative analysis of leukoaraiosis in T1- and T2-weighted images.

  15. Observations of RR Lyrae in M31 using Difference Imaging Photometry

    Science.gov (United States)

    Sugerman, B. E.; Uglesich, R. R.; Crotts, A. P. S.

    1999-05-01

    Due to distance and crowding, the incidence and population statistics of short-period variables in the inner parts of M31 are extremely poorly-determined. Specifically, RR Lyrae have an R ~ 25 superposed on a surface brightness between 18 and 20 mag arcsec(-2) at the inner disk, making them extremely enigmatic to detect. Pritchet & van den Bergh (1987, ApJ, 316, 517) found only 30 RR Lyrae candidates in the halo [40(') (9 kpc) from the nucleus] using the CFHT 3.6-m. Using the ``Difference Image Photometry'' (Tomaney & Crotts, 1996, AJ, 112, 2872) technique to isolate variable sources within unresolved fields, we seek to better determine the population of RR Lyrae in M31. Observations (including the VATT 1.8-m and INT 2.5-m) were made between Oct. 15 and Oct. 21, 1996 on a 10(') x 10(') far-side field 1.(') 5 (0.3 to 2.5 kpc) from the nucleus in the bulge/inner disk. Our current study is restricted to INT data. Identification of RR Lyrae is nontrivial since they lie deeply embedded within the unresolved bulge/disk. To achieve the required high S/N to identify candidate varirables, we median-combine differenced data by folding frames along a given test period at evenly-spaced phases. Since the constant background has been removed, any high-sigma residual is a potential variable-source. We compare the resulting light-curves against custom templates for a variety of short-period variables (including RRab, RRc and eclipsing binaries) to identify true variables and ignore sporadic signal. Adopting the metallicity and specific-incidence of RR Lyrae in M31 from Pritchet & van den Bergh, KPNO 4-m observations of M31 indicate that we expect to find ≲ 0.9 RR Lyrae per square arcsec. This corresponds to ≲ 3 x 10(5) RR Lyrae in our field. Since lower incidence indicates higher metallicity, this study is also a good diagnostic for metallicity, which is otherwise difficult to determine due to crowding. Preliminary estimates from findings on a small subsample of the full

  16. Comparison of Different Imaging Techniques for Tracking Cardiac Stem Cell Therapy

    Science.gov (United States)

    Zhang, Sarah J.; Wu, Joseph C.

    2013-01-01

    A growing number of exciting animal and preclinical studies are beginning to reveal the immense potential in stem cell-based therapies, particularly in the area of treating cardiovascular diseases. However, in order to evaluate the efficacy of these treatments in clinical trials, the transplanted stem cells must be monitored quantitatively and qualitatively in vivo. To date, several non-invasive imaging approaches have been used to follow stem cell fate in vivo. Here we review the basic principles of the current techniques for cardiac stem cell tracking, compare the relative advantages and disadvantages of these imaging modalities, and discuss the future prospect of cardiac stem cell trafficking. PMID:18056330

  17. The different ways to obtain digital images of urine microscopy findings: Their advantages and limitations.

    Science.gov (United States)

    Fogazzi, G B; Garigali, G

    2017-03-01

    We describe three ways to take digital images of urine sediment findings. Way 1 encompasses a digital camera permanently mounted on the microscope and connected with a computer equipped with a proprietary software to acquire, process and store the images. Way 2 is based on the use of inexpensive compact digital cameras, held by hands - or mounted on a tripod - close to one eyepiece of the microscope. Way 3 is based on the use of smartphones, held by hands close to one eyepiece of the microscope or connected to the microscope by an adapter. The procedures, advantages and limitations of each way are reported. Copyright © 2017. Published by Elsevier B.V.

  18. Assessment of tumour invasion into the mandible: the value of different imaging techniques

    Energy Technology Data Exchange (ETDEWEB)

    Brekel, M.W.M. van den; Tiwari, R.M.; Snow, G.B. [Dept. of Otorhinolaryngology/Head and Neck Surgery, Free University Hospital, Amsterdam (Netherlands); Runne, R.W. [Dept. of Otorhinolaryngology/Head and Neck Surgery, Free University Hospital, Amsterdam (Netherlands)]|[Dept. of Diagnostic Radiology, Free University Hospital, Amsterdam (Netherlands); Smeele, L.E. [Dept. of Oral and Maxillofacial Surgery/Pathology, Free University Hospital, Amsterdam (Netherlands); Castelijns, J.A. [Dept. of Diagnostic Radiology, Free University Hospital, Amsterdam (Netherlands)

    1998-12-01

    In oral carcinomas close to the mandible, tumour invasion of the mandible is important in selecting segmental or marginal resection. Imaging may play a role in assessing tumour invasion. This study compares the accuracy of panoramic X-ray, CT and MR imaging in assessing invasion of the mandible in 29 patients. At histopathology, 6 patients had mandible erosion, 12 had invasion and 11 had an intact mandible. Magnetic resonance imaging had the highest sensitivity (94 %), but a low specificity (73 %), with 3 of 11 intact mandibles interpreted as positive. Furthermore, MR often overestimated the extent of tumour invasion. On the other hand, CT and panoramic X-ray had a lower sensitivity (64 and 63 %, respectively) and a higher specificity (89 and 90 %, respectively). Computed tomography (using 5-mm sections) and panoramic X-ray had a similar accuracy, and negative findings do not exclude invasion. Magnetic resonance imaging was the most sensitive technique but had more false positives and frequently overestimated the extent of tumour invasion. Because none of the radiological techniques are accurate enough, clinical examination seems at present to remain the most important modality in deciding between segmental and marginal resection. Tumour invasion at CT or panoramic X-ray is a strong argument for a segmental resection. (orig.) With 3 figs., 3 tabs., 30 refs.

  19. Preservice Teachers' Images of Scientists: Do Prior Science Experiences Make a Difference?

    Science.gov (United States)

    Milford, Todd M.; Tippett, Christine D.

    2013-01-01

    This article presents the results of a mixed methods study that used the Draw-a-Scientist Test as a visual tool for exploring preservice teachers' beliefs about scientists. A questionnaire was also administered to 165 students who were enrolled in elementary (K-8) and secondary (8-12) science methods courses. Taken as a whole, the images drawn by…

  20. Spacial Variation in SAR Images of Different Resolution for Agricultural Fields

    DEFF Research Database (Denmark)

    Sandholt, Inge; Skriver, Henning

    1999-01-01

    The spatial variation in two types of Synthetic Aperture Radar (SAR) images covering agricultural fields is analysed. C-band polarimetric SAR data from the Danish airborne SAR, EMISAR, have been compared to space based ERS-1 C-band SAR with respect to scale and effect of polarization. The general...

  1. Fusion of images from different electro-optical sensing modalities for surveillance and navigation tasks

    NARCIS (Netherlands)

    Lewis, J.J.; Nikolov, S.G.; Canagarajah, C.N.; Bull, D.R.; Toet, A.

    2006-01-01

    Modern night-time cameras are designed to expand the conditions under which humans can operate. A functional piece of equipment must therefore provide an image that leads to good perceptual awareness in most environmental and operational conditions (to 'own the weather', or 'own the night'). The two

  2. Resolution-enhanced integral imaging using two micro-lens arrays with different focal lengths for capturing and display.

    Science.gov (United States)

    Wang, Zi; Wang, Anting; Wang, Shulu; Ma, Xiaohui; Ming, Hai

    2015-11-02

    We proposed a resolution enhanced integral imaging display method using two micro-lens arrays (MLA) with different focal lengths for capturing and display respectively. An elemental image array (EIA) is captured with MLA of focal length of f(1) and a processed EIA is displayed with MLA of focal length of f(2) which is larger than f(1). We enlarge the "effective area" in processed EIA to increase the information obtained by viewer, in other words, enhance the viewing resolution. The two micro-lens arrays for capturing and display are g and mg distant from display device respectively, and we can get m(2) times resolution enhancement.

  3. Images.

    Science.gov (United States)

    Barr, Catherine, Ed.

    1997-01-01

    The theme of this month's issue is "Images"--from early paintings and statuary to computer-generated design. Resources on the theme include Web sites, CD-ROMs and software, videos, books, and others. A page of reproducible activities is also provided. Features include photojournalism, inspirational Web sites, art history, pop art, and myths. (AEF)

  4. An Ensemble Method for Classifying Regional Disease Patterns of Diffuse Interstitial Lung Disease Using HRCT Images from Different Vendors.

    Science.gov (United States)

    Jun, Sanghoon; Kim, Namkug; Seo, Joon Beom; Lee, Young Kyung; Lynch, David A

    2017-12-01

    We propose the use of ensemble classifiers to overcome inter-scanner variations in the differentiation of regional disease patterns in high-resolution computed tomography (HRCT) images of diffuse interstitial lung disease patients obtained from different scanners. A total of 600 rectangular 20 × 20-pixel regions of interest (ROIs) on HRCT images obtained from two different scanners (GE and Siemens) and the whole lung area of 92 HRCT images were classified as one of six regional pulmonary disease patterns by two expert radiologists. Textual and shape features were extracted from each ROI and the whole lung parenchyma. For automatic classification, individual and ensemble classifiers were trained and tested with the ROI dataset. We designed the following three experimental sets: an intra-scanner study in which the training and test sets were from the same scanner, an integrated scanner study in which the data from the two scanners were merged, and an inter-scanner study in which the training and test sets were acquired from different scanners. In the ROI-based classification, the ensemble classifiers showed better (p ensemble classifiers also showed partial improvements in the intra- and inter-scanner tests. In the whole lung classification experiment, the quantification accuracies of the ensemble classifiers with integrated training (49.57%) were higher (p ensemble classifiers also showed better performance in both the intra- and inter-scanner experiments. We concluded that the ensemble classifiers provide better performance when using integrated scanner images.

  5. Positive body image: inter-ethnic and rural-urban differences among an indigenous sample from Malaysian Borneo.

    Science.gov (United States)

    Swami, Viren; Kannan, Kumaraswami; Furnham, Adrian

    2012-11-01

    Previous studies examining body image from a cross-cultural perspective have tended to neglect samples from different ethnic groups or along a rural-urban continuum. To overcome this limitation, the present study examined positive body image among rural and urban women from three major indigenous ethnic groups in Sabah, Malaysia. A total of 202 women completed the Body Appreciation Scale, as well as measures of media exposure and financial security, and provided their demographic details. s showed that there were significant rural-urban differences in body appreciation, with rural participants having significantly higher body appreciation than urban participants. A comparison with a previous data set of West Malaysian women (Swami & Chamorro-Premuzic, 2008) showed that the current urban sample had significantly lower body appreciation and that the rural group had significantly higher body appreciation. Further results showed that research site (urban vs rural) explained 11.0% of the variance in body appreciation. Participant body mass index and exposure to western forms of media explained an additional 2.0% of the variance. These results suggest that there are differences in body image between rural and urban women. Results are discussed in relation to the promotion of positive body image, particularly in developing societies where health care resources may be limited.

  6. Comparison of grey scale median (GSM) measurement in ultrasound images of human carotid plaques using two different softwares.

    Science.gov (United States)

    Östling, Gerd; Persson, Margaretha; Hedblad, Bo; Gonçalves, Isabel

    2013-11-01

    Grey scale median (GSM) measured on ultrasound images of carotid plaques has been used for several years now in research to find the vulnerable plaque. Centres have used different software and also different methods for GSM measurement. This has resulted in a wide range of GSM values and cut-off values for the detection of the vulnerable plaque. The aim of this study was to compare the values obtained with two different softwares, using different standardization methods, for the measurement of GSM on ultrasound images of carotid human plaques. GSM was measured with Adobe Photoshop(®) and with Artery Measurement System (AMS) on duplex ultrasound images of 100 consecutive medium- to large-sized carotid plaques of the Beta-blocker Cholesterol-lowering Asymptomatic Plaque Study (BCAPS). The mean values of GSM were 35·2 ± 19·3 and 55·8 ± 22·5 for Adobe Photoshop(®) and AMS, respectively. Mean difference was 20·45 (95% CI: 19·17-21·73). Although the absolute values of GSM differed, the agreement between the two measurements was good, correlation coefficient 0·95. A chi-square test revealed a kappa value of 0·68 when studying quartiles of GSM. The intra-observer variability was 1·9% for AMS and 2·5% for Adobe Photoshop. The difference between softwares and standardization methods must be taken into consideration when comparing studies. To avoid these problems, researcher should come to a consensus regarding software and standardization method for GSM measurement on ultrasound images of plaque in the arteries. © 2013 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  7. Gender differences in autobiographical memory for everyday events: retrieval elicited by SenseCam images versus verbal cues.

    Science.gov (United States)

    St Jacques, Peggy L; Conway, Martin A; Cabeza, Roberto

    2011-10-01

    Gender differences are frequently observed in autobiographical memory (AM). However, few studies have investigated the neural basis of potential gender differences in AM. In the present functional MRI (fMRI) study we investigated gender differences in AMs elicited using dynamic visual images vs verbal cues. We used a novel technology called a SenseCam, a wearable device that automatically takes thousands of photographs. SenseCam differs considerably from other prospective methods of generating retrieval cues because it does not disrupt the ongoing experience. This allowed us to control for potential gender differences in emotional processing and elaborative rehearsal, while manipulating how the AMs were elicited. We predicted that males would retrieve more richly experienced AMs elicited by the SenseCam images vs the verbal cues, whereas females would show equal sensitivity to both cues. The behavioural results indicated that there were no gender differences in subjective ratings of reliving, importance, vividness, emotion, and uniqueness, suggesting that gender differences in brain activity were not due to differences in these measures of phenomenological experience. Consistent with our predictions, the fMRI results revealed that males showed a greater difference in functional activity associated with the rich experience of SenseCam vs verbal cues, than did females.

  8. Looking at my body. Similarities and differences between anorexia nervosa patients and controls in body image visual processing.

    Science.gov (United States)

    Castellini, G; Polito, C; Bolognesi, E; D'Argenio, A; Ginestroni, A; Mascalchi, M; Pellicanò, G; Mazzoni, L N; Rotella, F; Faravelli, C; Pupi, A; Ricca, V

    2013-09-01

    Body image distortion is a core symptom of eating disorders. Functional magnetic resonance imaging (fMRI) studies on body image processing, described different patterns of neural response, mainly involving the inferior and superior parietal lobules, and the dorsolateral prefrontal cortex (DLPFC), with conflicting results. The neural response to the view of their own body pictures (normal size and distorted) was evaluated in 18 female anorexia nervosa (AN) restricting type patients, and in 19 healthy female subjects (HC) using fMRI. Clinical assessment was performed by means of the structured clinical interview for DSM-IV and self-reported questionnaires. In response to the body image distortion, patients and controls showed an inverse pattern of activation, with the widest extent of activation in the oversize condition in AN, while in the undersize condition in HC. AN and HC showed a similar pattern of neural response to the view of their own body, with an increased activation in the extrastriate body area, superior and inferior parietal lobule and prefrontal areas, although the extent of activation in HC was more limited as compared with AN patients. Increased activity in AN patients, compared with HC, was observed in the DLPFC in response to the oversized body picture and a significant correlation was found in AN patients between DLPFC activation and eating disorder psychopathology. Our findings suggest the existence of a continuum from normalcy to pathology in neural response to body image, and confirm the clinical relevance of body image distortion in AN, reinforcing the key role of attentive, executive and self-evaluation networks in AN visual processing of own distorted body image. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  9. Gender and Ethnic Differences in the Association Between Body Image Dissatisfaction and Binge Eating Disorder among Blacks.

    Science.gov (United States)

    Blostein, Freida; Assari, Shervin; Caldwell, Cleopatra Howard

    2017-08-01

    The research on binge eating has overwhelmingly focused on Whites. We aimed to study gender and ethnic differences in the association between body image dissatisfaction and binge eating in a nationally representative sample of Black adults in the USA. This cross-sectional study used data from the National Survey of American Life (NSAL), 2003-2004. Self-identified Caribbean Black (n = 1621) and African American (3570) adults aged 18 and older were enrolled. The independent variable was body dissatisfaction measured with two items. Using the World Health Organization Composite International Diagnostic Interview (WHO-CIDI), outcome was lifetime binge eating without hierarchy according to the DSM-IV criteria. Covariates included age, socioeconomic factors (i.e., education and marital status), and body mass index. Ethnicity and gender were focal moderators. Logistic regressions were used for data analysis. Despite comparable prevalence of lifetime binge eating (5 vs 4 %, p > 0.05), African Americans reported higher body image dissatisfaction than Caribbean Blacks (36 vs 29 %, p > 0.05). In the pooled sample, body dissatisfaction was a strong predictor of lifetime binge eating disorders. There was a significant interaction (p = 0.039) between ethnicity and body image dissatisfaction on binge eating, suggesting a stronger association between body image dissatisfaction and lifetime binge eating for Caribbean Blacks (OR = 11.65, 95 % 6.89-19.72) than African Americans (OR = 6.72, 95 % CI 3.97-11.37). Gender did not interact with body image dissatisfaction on binge eating. Ethnic variation in the link between body image dissatisfaction and binge eating may be due to within-race cultural differences in body image between African Americans and Caribbean Blacks. This may include different definitions, norms, and expectations regarding the body size. Findings suggest that ethnicity may bias relevance of body image dissatisfaction as a diagnostic criterion for

  10. A novel method for automatic determination of different stages of multiple sclerosis lesions in brain MR FLAIR images.

    Science.gov (United States)

    Khayati, Rasoul; Vafadust, Mansur; Towhidkhah, Farzad; Nabavi, S Massood

    2008-03-01

    It is very important to detect stages of multiple sclerosis (MS) lesions in order to exactly quantify involved voxels. In this paper, a novel method is proposed for automatic detection of different stages of MS lesions in the brain magnetic resonance (MR) images, in fluid attenuated inversion recovery (FLAIR) studies. In the proposed method, firstly, MS lesion voxels are segmented in FLAIR images based on adaptive mixtures method (AMM) and Markov Random Field (MRF) model. Then, signal intensity of each lesion voxel is modeled as a linear combination of signals related to the normal and also abnormal parts, in the voxel. By applying an optimal threshold, voxels with new intensities are primarily classified into two stages: previously destructed (chronic) and on going destruction (acute) lesions. Finally, the acute lesions, according to their activities, are classified, by another optimal threshold, into two new stages, early and recent acute. Evaluation of the proposed method was performed by manual segmentation of chronic and enhanced (early) acute lesions in gadolinium enhanced T1-weighted (Gad-E-T1-w) images by studying T1-weighted (T1-w) and T2-weighted (T2-w) images, using similarity criteria. The results showed a good correlation between the lesions segmented by the proposed method and by experts manually. Thus, the suggested method is useful to reduce the need for paramagnetic materials in contrast enhanced MR imaging which is a routine procedure for separation of acute and chronic lesions.

  11. Eating disorders and anabolic androgenic steroids in males--similarities and differences in self-image and psychiatric symptoms.

    Science.gov (United States)

    Björk, Tabita; Skårberg, Kurt; Engström, Ingemar

    2013-08-19

    Body dissatisfaction is common among both females and males. Dissatisfaction with the body is a risk factor both for onset of eating disorders and for abuse of anabolic androgenic steroids (AAS). Few studies have however investigated if there are other similarities in respect to self-image or psychiatric symptoms between clinical samples of eating disordered males and males in treatment for negative effects of AAS use. The aim of this study was to compare two clinical samples, one of males with ED and one of males who used AAS, regarding self-image and psychiatric symptoms. This study compared males with eating disorders (n = 13) and males who recently stopped AAS use (n = 29) on self-image and psychiatric symptoms, using The Structural Analysis of Social Behavior self-questionnaire and a shortened version of The Symptom Check List. The eating disorder group reported significantly lower scores for Self-emancipation and Active self-love and higher scores for Self-blame and Self-hate. Both groups reported serious psychiatric symptoms. The common denominator between groups was serious psychiatric symptomatology rather than negative self-image. The negative self-image profile, especially self-hate, found among males with Eating Disorders may indicate that the studied groups differ in aetiology of the underlying problems. The serious psychiatric symptoms in both groups call staff to pay attention to any thoughts of suicide due to severe depressive symptoms where by specialized psychiatric treatment may be needed.

  12. Brain abscesses after Serratia marcescens infection on a neonatal intensive care unit: differences on serial imaging

    Energy Technology Data Exchange (ETDEWEB)

    Messerschmidt, A.; Olischar, M.; Pollak, A.; Birnbacher, R. [Division of Neonatology and Intensive Care, Department of Paediatrics, University of Vienna, Wahringer Guertel 18-20, 1090, Vienna (Austria); Prayer, D. [Division of Radiology, University of Vienna, Waehringer Guertel 18-20, 1090, Vienna (Austria)

    2004-02-01

    Serratia are known to be a possible cause of severe cerebral infections in neonates. We describe imaging of three premature infants infected with Serratia marcescens. Born in the 31{sup st}, 25{sup th} and 28{sup th} weeks of gestation, they presented with signs of septicaemia on postnatal days 9, 24 and 32. Initial sonography showed cysts in the first child, two areas with anechoic centre and echogenic rim in the second, and several echogenic areas in the third. Lesions were seen on CT, of low density in two cases and minimally increased density in the third. MRI in the first patient showed cysts with incomplete contrast enhancement of the lesions, while patient 2 showed five ring-enhancing fluid-containing lesions with thick walls. In the third patient two abscesses with contrast enhancement and several high-signal spots were seen. We discuss the pathophysiology of the lesions and the impact of the various imaging methods. (orig.)

  13. Carbon dots of different composition and surface functionalization: cytotoxicity issues relevant to fluorescence cell imaging.

    Science.gov (United States)

    Wang, Yanli; Anilkumar, Parambath; Cao, Li; Liu, Jia-Hui; Luo, Pengju G; Tackett, Kenneth N; Sahu, Sushant; Wang, Ping; Wang, Xin; Sun, Ya-Ping

    2011-11-01

    Nanoscale carbon particles have emerged as versatile precursors for a new class of highly fluorescent nanomaterials that resemble semiconductor quantum dots. The surface-passivated fluorescent carbon nanoparticles, dubbed 'carbon dots', were already demonstrated for their potential optical bioimaging applications in vitro and in vivo. In this study, we conducted a systematic cytotoxicity evaluation on the carbon dots prepared by various combinations of precursor carbon nanoparticles and molecules for the particle surface functionalization. The results suggested that the cytotoxicity of carbon dots was dependent on the selection of surface passivation molecules. Those dots showing more significant cytotoxicity at higher concentrations were also evaluated for their effects on the fluorescence imaging of live cells. The implications of the results on the eventual use of carbon dots as cell imaging agents are discussed.

  14. Testing the performances of different image representations for mass classification in digital mammograms

    OpenAIRE

    Angelini, Enrico; Campanini, Renato; Iampieri, Emiro; Lanconelli, Nico; Masotti, Matteo; Roffilli, Matteo

    2006-01-01

    The classification of tumoral masses and normal breast tissue is targeted. A mass detection algorithm which does not refer explicitly to shape, border, size, contrast or texture of mammographic suspicious regions is evaluated. In the present approach, classification features are embodied by the image representation used to encode suspicious regions. Classification is performed by means of a support vector machine (SVM) classifier. To investigate whether improvements can be achieved with respe...

  15. A Second New Choroidal Osteoma in the Same Eye: Differences between Them with New Imaging Techniques

    Directory of Open Access Journals (Sweden)

    Javier Sambricio

    2015-01-01

    Full Text Available The authors introduce a 42-year-old woman with a choroidal osteoma. After 10 years the patient presented a second choroidal osteoma in the same eye; this osteoma has been growing in the last years. New tests that were unavailable during the first diagnosis were performed such as Fundus Autofluorescence or Enhanced Depth Imaging-Optical Coherence Tomography (EDI-OCT. These tests show characteristics of the tumors and allow us to realize a visual prognosis for the patient.

  16. Single nanoparticle imaging and characterization of different phospholipid-encapsulated quantum dot micelles.

    Science.gov (United States)

    Liu, Jianbo; Yang, Xiaohai; Wang, Kemin; He, Yan; Zhang, Pengfei; Ji, Haining; Jian, Lixin; Liu, Wei

    2012-07-17

    Phospholipid quantum dot (QD) micelles have been extensively used as fluorescent tags in single nanoparticle imaging for biomedical imaging. In this work, the microscopic structures and photophysical properties of the phospholipid QD micelles were studied at the single nanoparticle level. Two commonly used types of phospholipid QD micelles were prepared and tested both on a solid-phase surface and in liquid phase, including 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-encapsulated QD micelles (DSPE-QDMs) and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000]-encapsulated QD micelles (PEG-DSPE-QDMs). Their fluorescence intensities and diffusion trajectories were determined by a total internal reflection fluorescence-based single nanoparticle imaging platform and comparatively analyzed carefully. It was demonstrated that DSPE-QDMs possessed a comparably wider intensity distribution and lower diffusion coefficient than that of PEG-DSPE-QDMs. PEG-DSPE-QDMs exhibited an obvious fluorescent intermittence. The results suggested that for most of the DSPE-QDMs, more than one QD were encapsulated in a single micelle. On the other hand, only one QD was embedded in a single micelle of PEG-DSPE-QDMs for most of the cases. Such variances suggested that phospholipids play a key role in the fabrication of the QD micelles. This work provides a useful foundation for their further biomedical applications.

  17. Association Between Imaging Characteristics and Different Molecular Subtypes of Breast Cancer.

    Science.gov (United States)

    Wu, Mingxiang; Ma, Jie

    2017-04-01

    Breast cancer can be divided into four major molecular subtypes based on the expression of hormone receptor (estrogen receptor and progesterone receptor), human epidermal growth factor receptor 2, HER2 status, and molecular proliferation rate (Ki67). In this study, we sought to investigate the association between breast cancer subtype and radiological findings in the Chinese population. Medical records of 300 consecutive invasive breast cancer patients were reviewed from the database: the Breast Imaging Reporting and Data System. The imaging characteristics of the lesions were evaluated. The molecular subtypes of breast cancer were classified into four types: luminal A, luminal B, HER2 overexpressed (HER2), and basal-like breast cancer (BLBC). Univariate and multivariate logistic regression analyses were performed to assess the association between the subtype (dependent variable) and mammography or 15 magnetic resonance imaging (MRI) indicators (independent variables). Luminal A and B subtypes were commonly associated with "clustered calcification distribution," "nipple invasion," or "skin invasion" (P cancers showed association with persistent enhancement in the delayed phase on MRI and "clustered calcification distribution" on mammography (P breast tumor, which are potentially useful tools in the diagnosis and subtyping of breast cancer. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  18. Age-dependent differences in brain tissue microstructure assessed with neurite orientation dispersion and density imaging.

    Science.gov (United States)

    Merluzzi, Andrew P; Dean, Douglas C; Adluru, Nagesh; Suryawanshi, Gaurav S; Okonkwo, Ozioma C; Oh, Jennifer M; Hermann, Bruce P; Sager, Mark A; Asthana, Sanjay; Zhang, Hui; Johnson, Sterling C; Alexander, Andrew L; Bendlin, Barbara B

    2016-07-01

    Human aging is accompanied by progressive changes in executive function and memory, but the biological mechanisms underlying these phenomena are not fully understood. Using neurite orientation dispersion and density imaging, we sought to examine the relationship between age, cellular microstructure, and neuropsychological scores in 116 late middle-aged, cognitively asymptomatic participants. Results revealed widespread increases in the volume fraction of isotropic diffusion and localized decreases in neurite density in frontal white matter regions with increasing age. In addition, several of these microstructural alterations were associated with poorer performance on tests of memory and executive function. These results suggest that neurite orientation dispersion and density imaging is capable of measuring age-related brain changes and the neural correlates of poorer performance on tests of cognitive functioning, largely in accordance with published histological findings and brain-imaging studies of people of this age range. Ultimately, this study sheds light on the processes underlying normal brain development in adulthood, knowledge that is critical for differentiating healthy aging from changes associated with dementia. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Processing of rock core microtomography images: Using seven different machine learning algorithms

    Science.gov (United States)

    Chauhan, Swarup; Rühaak, Wolfram; Khan, Faisal; Enzmann, Frieder; Mielke, Philipp; Kersten, Michael; Sass, Ingo

    2016-01-01

    The abilities of machine learning algorithms to process X-ray microtomographic rock images were determined. The study focused on the use of unsupervised, supervised, and ensemble clustering techniques, to segment X-ray computer microtomography rock images and to estimate the pore spaces and pore size diameters in the rocks. The unsupervised k-means technique gave the fastest processing time and the supervised least squares support vector machine technique gave the slowest processing time. Multiphase assemblages of solid phases (minerals and finely grained minerals) and the pore phase were found on visual inspection of the images. In general, the accuracy in terms of porosity values and pore size distribution was found to be strongly affected by the feature vectors selected. Relative porosity average value of 15.92±1.77% retrieved from all the seven machine learning algorithm is in very good agreement with the experimental results of 17±2%, obtained using gas pycnometer. Of the supervised techniques, the least square support vector machine technique is superior to feed forward artificial neural network because of its ability to identify a generalized pattern. In the ensemble classification techniques boosting technique converged faster compared to bragging technique. The k-means technique outperformed the fuzzy c-means and self-organized maps techniques in terms of accuracy and speed.

  20. Optimal usage of cone beam computed tomography system with different field of views in image guided radiotherapy (IGRT

    Directory of Open Access Journals (Sweden)

    Narayana Venkata Naga Madhusudhana Sresty

    2015-09-01

    Full Text Available Purpose: To find methods for optimal usage of XVI (X-ray volume imaging system in Elekta synergy linear accelerator with different field of views for same lesion in order to minimize patient dose due to imaging.Methods: 20 scans of 2 individual patients with ca sigmoid colon and ca lung were used in this study. Kilo voltage collimators with medium field of view were used as per the preset information. Images were reconstructed for another collimator with small field of view. The set up errors were evaluated with XVI software. Shift results of both methods were compared. Results: Variation in treatment set up errors with M20 and S20 collimators were ≤ 0.2 mm in translational and 0.30 in rotational shifts. Results showed almost equal translational and rotational shifts in both medium and small field of views with different collimators in all the scans. Visualization of target and surrounding structures were good enough and sufficient for XVI auto matching.Conclusion: Imaging with small field of view results less patient dose compared with medium or large field of views. It is Suggestible to use collimators with small field of view wherever possible. In this study, collimators with small field of view were sufficient for both patients though the preset information indicated medium field of view. But, it always depends on the area required for matching purpose. So, individual selection is important than preset information in the XVI system.

  1. Measurement and image processing evaluation of surface modifications of dental implants G4 pure titanium created by different techniques

    Energy Technology Data Exchange (ETDEWEB)

    Bulutsuz, A. G., E-mail: asligunaya@gmail.com [Department of Mechanical Engineering, Yildiz Technical University, 34349 Besiktas, İstanbul (Turkey); Demircioglu, P., E-mail: pinar.demircioglu@adu.edu.tr; Bogrekci, I., E-mail: ismail.bogrekci@adu.edu.tr [Adnan Menderes University, Faculty of Engineering, Department of Mechanical Engineering, Aytepe, 09010, Aydin (Turkey); Durakbasa, M. N., E-mail: durakbasa@gmx.at [Department of Interchangeable Manufacturing and Industrial Metrology, Institute for Production Engineering and Laser Technology, Vienna University of Technology, Karlsplatz 13/3113 A-1040 Wien (Austria); Katiboglu, A. B., E-mail: abkatiboglu@hotmail.com [Istanbul University, Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Istanbul (Turkey)

    2015-03-30

    Foreign substances and organic tissue interaction placed into the jaw in order to eliminate tooth loss involves a highly complex process. Many biological reactions take place as well as the biomechanical forces that influence this formation. Osseointegration denotes to the direct structural and functional association between the living bone and the load-bearing artificial implant's surface. Taking into consideration of the requirements in the manufacturing processes of the implants, surface characterizations with high precise measurement techniques are investigated and thus long-term success of dental implant is emphasized on the importance of these processes in this study. In this research, the detailed surface characterization was performed to identify the dependence of the manufacturing techniques on the surface properties by using the image processing methods and using the scanning electron microscope (SEM) for morphological properties in 3D and Taylor Hobson stylus profilometer for roughness properties in 2D. Three implant surfaces fabricated by different manufacturing techniques were inspected, and a machined surface was included into the study as a reference specimen. The results indicated that different surface treatments were strongly influenced surface morphology. Thus 2D and 3D precise inspection techniques were highlighted on the importance for surface characterization. Different image analyses techniques such as Dark-light technique were used to verify the surface measurement results. The computational phase was performed using image processing toolbox in Matlab with precise evaluation of the roughness for the implant surfaces. The relationship between the number of black and white pixels and surface roughness is presented. FFT image processing and analyses results explicitly imply that the technique is useful in the determination of surface roughness. The results showed that the number of black pixels in the image increases with increase in

  2. Calculating and Comparison of Different Vegetation Indices by Using Landsat ETM+ Images to Study Vegetation Cover in Neyshabour Area

    Directory of Open Access Journals (Sweden)

    M. Ghaemi

    2011-01-01

    Full Text Available Abstract Understanding plant cover performance in a region is one of the most important factors in controlling soil fertility and its management. In studying plant cover by using of traditional field data collection methods are difficult and time consuming. Using of GIS data in vegetation cover studies satellite images can be helpful in reducing of time and obtaining more precise information. In this study different aspects were considered to obtain the best composite of different indices and identifying the most suitable parameters. The related bands obtained from tasseled cap, principal components analysis and the calculated indices were also used to evaluate the role and effects of different filters on Landsat ETM+ of Neyshabour region. Regression equation and regression coefficients of different parameters were analyzed and evaluated. Finally the most applicable indices were compared with the classes obtained from image classification. The results showed that mean filter of 3×3 has higher correlation coefficients when digital numbers were compared with field collected data. The indices of MSR,VI5, VI6, VI1, RI, BI1, SI, NDVI,TVI ,NDSI ,SAVI,MND, MSAVI, Complex multiratoو COSRI and also PCA1 and the PCA3 obtained from principal components analyses, brightness and greenness bands received from tasseled cap conversion are providing better recognition and evaluation of plant cover in the region. Keywords: Vegetation indices, Principal components analysis, Tasseled cap, Image classification, Landsat

  3. Evaluation of 2 different x-ray digital systems designed for cardiovascular angiography: patient dosimetry data and image quality

    Energy Technology Data Exchange (ETDEWEB)

    Octavian Dragusin; Kristien Smans; Hilde Bosmans [Department of Radiology, Gasthuisberg Hospital, Leuven (Belgium); Walter Desmet [Department of Cardiology, Gasthuisberg Hospital, Leuven (Belgium)

    2006-07-01

    The goal of this study was the comparative assessment of dose and image quality performance of a new flat-panel detector (F.D.) and an image intensifier (II) charge coupled device (C.C.D.) installed in a Catheterization laboratory (Cathlab). Poly-methyl methacrylate (PMMA) plates were used to simulate different patient size (10,15,20,25,30 cm). Entrance dose to the phantom and image quality of a test object (Leeds T.O.R. 18-F.G.) were measured. For analysis of image quality, two methods were used. Firstly, images were evaluated directly on the monitor (low contrast resolution and high spatial resolution). Secondly, a numerical method was used (noise and signal-to-noise ratio). Finally a preliminary patient dose survey for the two most common interventional cardiology procedures (coronary angiography C.A. and percutaneous transluminal coronary angioplasty - P.T.C.A.) was performed. Dose area product (D.A.P.), fluoroscopy time (F.T.) and total number of frames (No. frames) were collected. The results showed that both systems performed within international recommendations; the F.D. system seems superior to the II system, in terms of entrance doses of the phantom and image quality. Surprisingly, however, this potential dose reduction is not reflected in the patient data; D.A.P. values of patient data were not significantly reduced with the new system. This underlines the need for a careful set-up of the system and a more detailed analysis of the procedure. (authors)

  4. Effect of using different U/S probe Standoff materials in image geometry for interventional procedures: the example of prostate

    Directory of Open Access Journals (Sweden)

    Dimos Baltas

    2011-12-01

    Full Text Available Purpose: This study investigates the distortion of geometry of catheters and anatomy in acquired U/S images, caused by utilizing various stand-off materials for covering a transrectal bi-planar ultrasound probe in HDR and LDR prostatebrachytherapy, biopsy and other interventional procedures. Furthermore, an evaluation of currently established waterbathbased quality assurance (QA procedures is presented. Material and methods: Image acquisitions of an ultrasound QA setup were carried out at 5 MHz and 7 MHz. The U/Sprobe was covered by EA 4015 Silicone Standoff kit, or UA0059 Endocavity balloon filled either with water or one ofthe following: 40 ml of Endosgel®, Instillagel®, Ultraschall gel or Space OAR™ gel. The differences between imageswere recorded. Consequently, the dosimetric impact of the observed image distortion was investigated, using a tissueequivalent ultrasound prostate phantom – Model number 053 (CIRS Inc., Norfolk, VA, USA. Results: By using the EA 4015 Silicone Standoff kit in normal water with sound speed of 1525 m/s, a 3 mm needleshift was observed. The expansion of objects appeared in radial direction. The shift deforms also the PTV (prostate inour case and other organs at risk (OARs in the same way leading to overestimation of volume and underestimationof the dose. On the other hand, Instillagel® and Space OAR™ “shrinks” objects in an ultrasound image for 0.65 mm and0.40 mm, respectively. Conclusions: The use of EA 4015 Silicone Standoff kit for image acquisition, leads to erroneous contouring of PTVand OARs and reconstruction and placement of catheters, which results to incorrect dose calculation during prostatebrachytherapy. Moreover, the reliability of QA procedures lies mostly in the right temperature of the water used foraccurate simulation of real conditions of transrectal ultrasound imaging.

  5. Brain perfusion imaging using a Reconstruction-of-Difference (RoD) approach for cone-beam computed tomography

    Science.gov (United States)

    Mow, M.; Zbijewski, W.; Sisniega, A.; Xu, J.; Dang, H.; Stayman, J. W.; Wang, X.; Foos, D. H.; Koliatsos, V.; Aygun, N.; Siewerdsen, J. H.

    2017-03-01

    Purpose: To improve the timely detection and treatment of intracranial hemorrhage or ischemic stroke, recent efforts include the development of cone-beam CT (CBCT) systems for perfusion imaging and new approaches to estimate perfusion parameters despite slow rotation speeds compared to multi-detector CT (MDCT) systems. This work describes development of a brain perfusion CBCT method using a reconstruction of difference (RoD) approach to enable perfusion imaging on a newly developed CBCT head scanner prototype. Methods: A new reconstruction approach using RoD with a penalized-likelihood framework was developed to image the temporal dynamics of vascular enhancement. A digital perfusion simulation was developed to give a realistic representation of brain anatomy, artifacts, noise, scanner characteristics, and hemo-dynamic properties. This simulation includes a digital brain phantom, time-attenuation curves and noise parameters, a novel forward projection method for improved computational efficiency, and perfusion parameter calculation. Results: Our results show the feasibility of estimating perfusion parameters from a set of images reconstructed from slow scans, sparse data sets, and arc length scans as short as 60 degrees. The RoD framework significantly reduces noise and time-varying artifacts from inconsistent projections. Proper regularization and the use of overlapping reconstructed arcs can potentially further decrease bias and increase temporal resolution, respectively. Conclusions: A digital brain perfusion simulation with RoD imaging approach has been developed and supports the feasibility of using a CBCT head scanner for perfusion imaging. Future work will include testing with data acquired using a 3D-printed perfusion phantom currently and translation to preclinical and clinical studies.

  6. Scaling of Thermal Images at Different Spatial Resolution: The Mixed Pixel Problem

    Directory of Open Access Journals (Sweden)

    Hamlyn G. Jones

    2014-07-01

    Full Text Available The consequences of changes in spatial resolution for application of thermal imagery in plant phenotyping in the field are discussed. Where image pixels are significantly smaller than the objects of interest (e.g., leaves, accurate estimates of leaf temperature are possible, but when pixels reach the same scale or larger than the objects of interest, the observed temperatures become significantly biased by the background temperature as a result of the presence of mixed pixels. Approaches to the estimation of the true leaf temperature that apply both at the whole-pixel level and at the sub-pixel level are reviewed and discussed.

  7. The out-of-body experience and body image : Differences between experients and non-experients.

    OpenAIRE

    Murray, Craig; Fox, Jezz

    2005-01-01

    The present study sought to examine various aspects of body image for persons reporting a prior out-of-body experience (OBE). A total of 64 people took part in the study, 34 of whom had had an OBE. Participants reporting a previous OBE were found to score significantly higher on measures of body dissatisfaction, Social Physique Anxiety and Somatoform Dissociation, and lower on a measure of Physical Self-Presentation. OBE experients also reported lower levels of body awareness during use of an...

  8. The out-of-body experience and body image: differences between experiments and nonexperiments.

    Science.gov (United States)

    Murray, Craig; Fox, Jezz

    2005-01-01

    The present study sought to examine various aspects of body image for persons reporting a previous out-of-body experience (OBE). A total of 64 people took part in the study, 34 of whom had had an OBE. Participants reporting a previous OBE were found to score significantly higher on measures of body dissatisfaction, social physique anxiety, and somatoform dissociation, and lower on a measure of physical self-presentation. OBE experiments also reported lower levels of body awareness during use of an immersive virtual reality system than nonexperiments.

  9. Evaluation of proximal caries in images resulting from different modes of radiographic digitalization.

    Science.gov (United States)

    Xavier, C R G; Araujo-Pires, Ana Claudia; Poleti, M L; Rubira-Bullen, I R F; Ferreira, O; Capelozza, A L A

    2011-09-01

    The aim of this study was to evaluate the performances of observers in diagnosing proximal caries in digital images obtained from digital bitewing radiographs using two scanners and four digital cameras in Joint Photographic Experts Group (JPEG) and tagged image file format (TIFF) files, and comparing them with the original conventional radiographs. In total, 56 extracted teeth were radiographed with Kodak Insight film (Eastman Kodak, Rochester, NY) in a Kaycor Yoshida X-ray device (Kaycor X-707; Yoshida Dental Manufacturing Co., Tokyo, Japan) operating at 70 kV and 7 mA with an exposure time of 0.40 s. The radiographs were obtained and scanned by CanonScan D646U (Canon USA Inc., Newport News, VA) and Genius ColorPage HR7X (KYE Systems Corp. America, Doral, FL) scanners, and by Canon Powershot G2 (Canon USA Inc.), Canon RebelXT (Canon USA Inc.), Nikon Coolpix 8700 (Nikon Inc., Melville, NY), and Nikon D70s (Nikon Inc.) digital cameras in JPEG and TIFF formats. Three observers evaluated the images. The teeth were then observed under the microscope in polarized light for the verification of the presence and depth of the carious lesions. The probability of no diagnosis ranged from 1.34% (Insight film) to 52.83% (CanonScan/JPEG). The sensitivity ranged from 0.24 (Canon RebelXT/JPEG) to 0.53 (Insight film), the specificity ranged from 0.93 (Nikon Coolpix/JPEG, Canon Powershot/TIFF, Canon RebelXT/JPEG and TIFF) to 0.97 (CanonScan/TIFF and JPEG) and the accuracy ranged from 0.82 (Canon RebelXT/JPEG) to 0.91 (CanonScan/JPEG). The carious lesion diagnosis did not change in either of the file formats (JPEG and TIFF) in which the images were saved for any of the equipment used. Only the CanonScan scanner did not have adequate performance in radiography digitalization for caries diagnosis and it is not recommended for this purpose.

  10. Differences in Brand Image of Online Chat Application of Blackberry Messenger, Whatsapp, and Line for Bina Nusantara University’s Student

    Directory of Open Access Journals (Sweden)

    Kuspuji C. B. Wicaksono

    2016-05-01

    Full Text Available This article was written to find out whether there were any differences on brand image for each online chat Application such as Blackberry Messenger, Whatsapp, and LINE based on six factors of the brand image which are: benefits, attributes, cultures, values, personality, and user. Data for the research were collected from questionnaires given to respondents who had used each mention online chat application. Then each respondent was asked to give scores based on the six factors of brand image for each online chat Application. Using the ANOVA method for testing the differences between brand images for each online chat application. The result reveales that there are differences in the brand image between BlackBerry Messenger, Whatsapp, and LINE for benefits, cultures, and values. There is no difference in attributes, and personality cannot be tested. The company that creates online chat application are expected to improve their brand image to distinguish one another differently.

  11. Tilt-pair analysis of images from a range of different specimens in single-particle electron cryomicroscopy.

    Science.gov (United States)

    Henderson, Richard; Chen, Shaoxia; Chen, James Z; Grigorieff, Nikolaus; Passmore, Lori A; Ciccarelli, Luciano; Rubinstein, John L; Crowther, R Anthony; Stewart, Phoebe L; Rosenthal, Peter B

    2011-11-11

    The comparison of a pair of electron microscope images recorded at different specimen tilt angles provides a powerful approach for evaluating the quality of images, image-processing procedures, or three-dimensional structures. Here, we analyze tilt-pair images recorded from a range of specimens with different symmetries and molecular masses and show how the analysis can produce valuable information not easily obtained otherwise. We show that the accuracy of orientation determination of individual single particles depends on molecular mass, as expected theoretically since the information in each particle image increases with molecular mass. The angular uncertainty is less than 1° for particles of high molecular mass (~50 MDa), several degrees for particles in the range 1-5 MDa, and tens of degrees for particles below 1 MDa. Orientational uncertainty may be the major contributor to the effective temperature factor (B-factor) describing contrast loss and therefore the maximum resolution of a structure determination. We also made two unexpected observations. Single particles that are known to be flexible showed a wider spread in orientation accuracy, and the orientations of the largest particles examined changed by several degrees during typical low-dose exposures. Smaller particles presumably also reorient during the exposure; hence, specimen movement is a second major factor that limits resolution. Tilt pairs thus enable assessment of orientation accuracy, map quality, specimen motion, and conformational heterogeneity. A convincing tilt-pair parameter plot, where 60% of the particles show a single cluster around the expected tilt axis and tilt angle, provides confidence in a structure determined using electron cryomicroscopy. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. High-resolution imaging of Kepler planet host candidates. A comprehensive comparison of different techniques

    Science.gov (United States)

    Lillo-Box, J.; Barrado, D.; Bouy, H.

    2014-06-01

    Context. The Kepler mission has discovered thousands of planet candidates. Currently, some of them have already been discarded; more than 200 have been confirmed by follow-up observations (most by radial velocity and few by other methods), and several hundreds have been validated. However, the large majority of the candidates are still awaiting for confirmation. Thus, priorities (in terms of the probability of the candidate being a real planet) must be established for subsequent radial velocity observations. Aims: The motivation of this work is to provide a set of isolated (good) host candidates to be further tested by other techniques that allow confirmation of the planet. As a complementary goal, we aim to identify close companions of the candidates that could have contaminated the light curve of the planet host due to the large pixel size of the Kepler CCD and its typical PSF of around 6 arcsec. Both goals can also provide robust statistics about the multiplicity of the Kepler hosts. Methods: We used the AstraLux North instrument located at the 2.2 m telescope in the Calar Alto Observatory (Almería, Spain) to obtain diffraction-limited images of 174 Kepler objects of interest. A sample of demoted Kepler objects of interest (with rejected planet candidates) is used as a control for comparison of multiplicity statistics. The lucky-imaging technique used in this work is compared to other adaptive optics and speckle imaging observations of Kepler planet host candidates. To that end, we define a new parameter, the blended source confidence level (BSC), to assess the probability of an object to have blended non-detected eclipsing binaries capable of producing the detected transit. Results: We find that 67.2% of the observed Kepler hosts are isolated within our detectability limits, and 32.8% have at least one visual companion at angular separations below 6 arcsec. Indeed, we find close companions (below 3 arcsec) for the 17.2% of the sample. The planet properties of

  13. The impact of different antiepileptic drugs on the sedation of children during magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Isil Davarci

    2014-10-01

    Full Text Available Background and objectives:The induction and inhibition of cytochrome P450 isoenzymes by antiepileptic drugs lead to changes in the clearance of anesthetic drugs eliminated via hepatic metabolism. We investigated the duration of the sedation and additional anesthetic needs during magnetic resonance imaging in epileptic children receiving antiepileptic drugs that cause either enzyme induction or inhibition.Methods:In American Society of Anesthesiology I–II, 120 children aged 3–10 years were included. Group 1: children using antiepileptic drugs that cause cytochrome P450 enzyme induction; Group 2: those using antiepileptic drugs that cause inhibition; and Group 3: those that did not use antiepileptic drugs. Sedation was induced with the use of 0.05 mg kg−1 midazolam and 1 mg kg−1 propofol. An additional 0.05 mg kg−1 of midazolam and rescue propofol (0.5 mg kg−1 were administered and repeated to maintain sedation. The duration of sedation and the additional sedation needed were compared.Results:The duration of the initial dose was significantly shorter in Group I compared with groups II and III (p = 0.001, p = 0.003, respectively. It was significantly longer in Group II compared with groups I and III (p = 0.001, p = 0.029, respectively. The additional midazolam needed for adequate sedation was increased in Group I when compared with groups II and III (p = 0.010, p = 0.001, respectively. In addition, the rescue propofol dose was significantly higher only in Group I when compared with Group III (p = 0.002.Conclusion:In epileptic children, the response variability to the initial sedative agents during the magnetic resonance imaging procedure resulting from the inhibition or induction of the cytochrome P450 isoenzymes by the antiepileptic drugs mandated the titration of anesthetic agents.

  14. Comparison Of Processing Time Of Different Size Of Images And Video Resolutions For Object Detection Using Fuzzy Inference System

    Directory of Open Access Journals (Sweden)

    Yogesh Yadav

    2017-01-01

    Full Text Available Object Detection with small computation cost and processing time is a necessity in diverse domains such as traffic analysis security cameras video surveillance etc .With current advances in technology and decrease in prices of image sensors and video cameras the resolution of captured images is more than 1MP and has higher frame rates. This implies a considerable data size that needs to be processed in a very short period of time when real-time operations and data processing is needed. Real time video processing with high performance can be achieved with GPU technology. The aim of this study is to evaluate the influence of different image and video resolutions on the processing time number of objects detections and accuracy of the detected object. MOG2 algorithm is used for processing video input data with GPU module. Fuzzy interference system is used to evaluate the accuracy of number of detected object and to show the difference between CPU and GPU computing methods.

  15. Is magnetic resonance imaging of hepatic hemangioma any different in liver fibrosis and cirrhosis compared to normal liver?

    Science.gov (United States)

    Duran, Rafael; Ronot, Maxime; Di Renzo, Sara; Gregoli, Bettina; Van Beers, Bernard E; Vilgrain, Valérie

    2015-05-01

    To compare qualitative and quantitative magnetic resonance (MR) imaging characteristics of hepatic hemangiomas in patients with normal, fibrotic and cirrhotic livers. Retrospective, institutional review board approved study (waiver of informed consent). Eighty-nine consecutive patients with 231 hepatic hemangiomas who underwent liver MR imaging for lesion characterization were included. Lesions were classified into three groups according to the patients' liver condition: no underlying liver disease (group 1), fibrosis (group 2) and cirrhosis (group 3). Qualitative and quantitative characteristics (number, size, signal intensities on T1-, T2-, and DW MR images, T2 shine-through effect, enhancement patterns (classical, rapidly filling, delayed filling), and ADC values) were compared. There were 160 (69%), 45 (20%), and 26 (11%) hemangiomas in groups 1, 2 and 3, respectively. Lesions were larger in patients with normal liver (group 1 vs. groups 2 and 3; P=.009). No difference was found between the groups on T2-weighted images (fat-suppressed fast spin-echo (P=.82) and single-shot (P=.25)) and in enhancement patterns (P=.56). Mean ADC values of hemangiomas were similar between groups 1, 2 and 3 (2.11±.52×10(-3) mm(2)/s, 2.1±.53×10(-3) mm(2)/s and 2.14±.44×10(-3) mm(2)/s, P=87, respectively). T2 shine-through effect was less frequently observed in cirrhosis (P=.02). MR imaging characteristics of hepatic hemangioma were similar in patients with normal compared to fibrotic and cirrhotic livers. Smaller lesion size was observed with liver disease and less T2 shine-through effect was seen in hemangiomas developed on cirrhosis, the latter being an important finding to highlight in these patients at risk of developing hepatocellular carcinoma. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. Eating disorders and anabolic androgenic steroids in males - similarities and differences in self-image and psychiatric symptoms

    Science.gov (United States)

    2013-01-01

    Background Body dissatisfaction is common among both females and males. Dissatisfaction with the body is a risk factor both for onset of eating disorders and for abuse of anabolic androgenic steroids (AAS). Few studies have however investigated if there are other similarities in respect to self-image or psychiatric symptoms between clinical samples of eating disordered males and males in treatment for negative effects of AAS use. Aim The aim of this study was to compare two clinical samples, one of males with ED and one of males who used AAS, regarding self-image and psychiatric symptoms. Methods This study compared males with eating disorders (n = 13) and males who recently stopped AAS use (n = 29) on self-image and psychiatric symptoms, using The Structural Analysis of Social Behavior self-questionnaire and a shortened version of The Symptom Check List. Results The eating disorder group reported significantly lower scores for Self-emancipation and Active self-love and higher scores for Self-blame and Self-hate. Both groups reported serious psychiatric symptoms. The common denominator between groups was serious psychiatric symptomatology rather than negative self-image. Conclusions The negative self-image profile, especially self-hate, found among males with Eating Disorders may indicate that the studied groups differ in aetiology of the underlying problems. The serious psychiatric symptoms in both groups call staff to pay attention to any thoughts of suicide due to severe depressive symptoms where by specialized psychiatric treatment may be needed. PMID:23958408

  17. Interobserver variability of patient positioning using four different CT datasets for image registration in lung stereotactic body radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Oechsner, Markus [Technical University of Munich, Department of Radiation Oncology, Klinikum rechts der Isar, Muenchen (Germany); Technical University of Munich, Zentrum fuer Stereotaxie und personalisierte Hochpraezisionsstrahlentherapie (StereotakTUM), Munich (Germany); Chizzali, Barbara; Devecka, Michal; Muench, Stefan [Technical University of Munich, Department of Radiation Oncology, Klinikum rechts der Isar, Muenchen (Germany); Combs, Stephanie Elisabeth; Wilkens, Jan Jakob; Duma, Marciana Nona [Technical University of Munich, Department of Radiation Oncology, Klinikum rechts der Isar, Muenchen (Germany); Technical University of Munich, Zentrum fuer Stereotaxie und personalisierte Hochpraezisionsstrahlentherapie (StereotakTUM), Munich (Germany); Helmholtz Zentrum Muenchen, Institute of Innovative Radiotherapy (iRT), Munich (Germany)

    2017-10-15

    To assess the impact of different reference CT datasets on manual image registration with free-breathing three-dimensional (3D) cone beam CTs (FB-CBCT) for patient positioning by several observers. For 48 patients with lung lesions, manual image registration with FB-CBCTs was performed by four observers. A slow planning CT (PCT), average intensity projection (AIP), maximum intensity projection (MIP), and midventilation CT (MidV) were used as reference images. Couch shift differences between the four reference CT datasets for each observer as well as shift differences between the observers for the same reference CT dataset were determined. Statistical analyses were performed and correlations between the registration differences and the 3D tumor motion and the CBCT score were calculated. The mean 3D shift difference between different reference CT datasets was the smallest for AIPvsMIP (range 1.1-2.2 mm) and the largest for MidVvsPCT (2.8-3.5 mm) with differences >10 mm. The 3D shifts showed partially significant correlations to 3D tumor motion and CBCT score. The interobserver comparison for the same reference CTs resulted in the smallest ∇3D mean differences and mean ∇3D standard deviation for ∇AIP (1.5 ± 0.7 mm, 0.7 ± 0.4 mm). The maximal 3D shift difference between observers was 10.4 mm (∇MidV). Both 3D tumor motion and mean CBCT score correlated with the shift differences (R{sub s} = 0.336-0.740). The applied reference CT dataset impacts image registration and causes interobserver variabilities. The 3D tumor motion and CBCT quality affect shift differences. The smallest differences were found for AIP which might be the most appropriate CT dataset for image registration with FB-CBCT. (orig.) [German] Untersuchung des Einflusses verschiedener Referenz-CT-Datensaetze auf die manuelle Bildregistrierung mit dreidimensionaler (3D) ConeBeam-Computertomographie in freier Atmung (FB-CBCT) zur Patientenpositionierung durch verschiedene Observer. Bei 48 Patienten

  18. EFM data mapped into 2D images of tip-sample contact potential difference and capacitance second derivative

    Science.gov (United States)

    Lilliu, S.; Maragliano, C.; Hampton, M.; Elliott, M.; Stefancich, M.; Chiesa, M.; Dahlem, M. S.; MacDonald, J. E.

    2013-11-01

    We report a simple technique for mapping Electrostatic Force Microscopy (EFM) bias sweep data into 2D images. The method allows simultaneous probing, in the same scanning area, of the contact potential difference and the second derivative of the capacitance between tip and sample, along with the height information. The only required equipment consists of a microscope with lift-mode EFM capable of phase shift detection. We designate this approach as Scanning Probe Potential Electrostatic Force Microscopy (SPP-EFM). An open-source MATLAB Graphical User Interface (GUI) for images acquisition, processing and analysis has been developed. The technique is tested with Indium Tin Oxide (ITO) and with poly(3-hexylthiophene) (P3HT) nanowires for organic transistor applications.

  19. Biological fiducial point based registration for multiple brain tissues reconstructed from different imaging modalities

    Science.gov (United States)

    Wu, Huiqun; Zhou, Gangping; Geng, Xingyun; Zhang, Xiaofeng; Jiang, Kui; Tang, Lemin; Zhou, Guomin; Dong, Jiancheng

    2013-10-01

    With the development of computer aided navigation system, more and more tissues shall be reconstructed to provide more useful information for surgical pathway planning. In this study, we aimed to propose a registration framework for different reconstructed tissues from multi-modalities based on some fiducial points on lateral ventricles. A male patient with brain lesion was admitted and his brain scans were performed by different modalities. Then, the different brain tissues were segmented in different modality with relevant suitable algorithms. Marching cubes were calculated for three dimensional reconstructions, and then the rendered tissues were imported to a common coordinate system for registration. Four pairs of fiducial markers were selected to calculate the rotation and translation matrix using least-square measure method. The registration results were satisfied in a glioblastoma surgery planning as it provides the spatial relationship between tumors and surrounding fibers as well as vessels. Hence, our framework is of potential value for clinicians to plan surgery.

  20. Characterizing the contrast of white matter and grey matter in high-resolution phase difference enhanced imaging of human brain at 3.0 T

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Li [Fudan University, Department of Radiology, Shanghai Institute of Medical Imaging, Zhongshan Hospital, Shanghai (China); Shandong University, Shandong Medical Imaging Research Institute, Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-cerebral Vascular Diseases, Jinan, Shandong (China); Wang, Shanshan; Yao, Bin; Li, Lili; Guo, Lingfei; Zhang, Xinjuan; Wang, Guangbin [Shandong University, Shandong Medical Imaging Research Institute, Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-cerebral Vascular Diseases, Jinan, Shandong (China); Xu, Xiaofei [Erasmus University Rotterdam, Laboratory of Experimental Tumor Immunology, Department of Medical Oncology, Erasmus Medical Center Cancer Institute, Rotterdam (Netherlands); Zhao, Lianxin [Shandong University, Department of Radiology, Qilu Hospital, Jinan, Shandong (China); Chen, Weibo; Chan, Queenie [Philips Healthcare, Shanghai (China)

    2015-04-01

    The purpose of this study was to address the feasibility of characterizing the contrast both between and within grey matter and white matter using the phase difference enhanced (PADRE) technique. PADRE imaging was performed in 33 healthy volunteers. Vessel enhancement (VE), tissue enhancement (TE), and PADRE images were reconstructed from source images and were evaluated with regard to differentiation of grey-to-white matter interface, the stria of Gennari, and the two layers, internal sagittal stratum (ISS) and external sagittal stratum (ESS), of optic radiation. White matter regions showed decreased signal intensity compared to grey matter regions. Discrimination was sharper between white matter and cortical grey matter in TE images than in PADRE images, but was poorly displayed in VE images. The stria of Gennari was observed on all three image sets. Low-signal-intensity bands displayed in VE images representing the optic radiation were delineated as two layers of different signal intensities in TE and PADRE images. Statistically significant differences in phase shifts were found between frontal grey and white matter, as well as between ISS and ESS (p < 0.01). The PADRE technique is capable of identifying grey-to-white matter interface, the stria of Gennari, and ISS and ESS, with improved contrast in PADRE and TE images compared to VE images. (orig.)

  1. Comparison of longitudinal sciatic nerve movement with different mobilization exercises: an in vivo study utilizing ultrasound imaging.

    Science.gov (United States)

    Ellis, Richard F; Hing, Wayne A; McNair, Peter J

    2012-08-01

    Controlled laboratory study using a single-group, within-subjects comparison. To determine whether different types of neural mobilization exercises are associated with differing amounts of longitudinal sciatic nerve excursion measured in vivo at the posterior midthigh region. Recent research focusing on the upper limb of healthy subjects has shown that nerve excursion differs significantly between different types of neural mobilization exercises. This has not been examined in the lower limb. It is important to initially examine the influence of neural mobilization on peripheral nerve excursion in healthy people to identify peripheral nerve excursion impairments under conditions in which nerve excursion may be compromised. High-resolution ultrasound imaging was used to assess sciatic nerve excursion at the posterior midthigh region. Four different neural mobilization exercises were performed in 31 healthy participants. These neural mobilization exercises used combinations of knee extension and cervical spine flexion and extension. Frame-by-frame cross-correlation analysis of the ultrasound images was used to calculate nerve excursion. A repeated-measures analysis of variance and isolated means comparisons were used for data analysis. Different neural mobilization exercises induced significantly different amounts of sciatic nerve excursion at the posterior midthigh region (Ptensioner exercise (simultaneous cervical spine flexion and knee extension). The single-joint neck flexion exercise resulted in the least amount of sciatic nerve excursion at the posterior midthigh (mean ± SD, -0.1 ± 0.1 mm), which was significantly smaller than the other 3 exercises (P<.001). These findings are consistent with the results of previous research that has examined median nerve excursion associated with different neural mobilization exercises. Such nerve excursion supports theories of nerve motion associated with cervical spine and extremity movement, as generalizable to the lower

  2. Novel Application of Magnetic Resonance Imaging Demonstrates Characteristic Differences in Vasculature at Predilection Sites of Osteochondritis Dissecans.

    Science.gov (United States)

    Tóth, Ferenc; Nissi, Mikko J; Ellermann, Jutta M; Wang, Luning; Shea, Kevin G; Polousky, John; Carlson, Cathy S

    2015-10-01

    Understanding the pathogenesis of osteochondrosis/osteochondritis dissecans and other developmental orthopaedic diseases that are thought to occur secondary to defects in vascular supply to growth/epiphyseal cartilage has been hampered by the inability to image the vasculature in this tissue. This is particularly true in human beings due to limitations of current imaging techniques and the lack of availability of appropriate cadaveric samples for histological studies. Susceptibility-weighted imaging, an MRI sequence, allows identification of characteristic differences in the vascular architecture in species that are affected by osteochondrosis/osteochondritis dissecans on the femoral condyle (humans and pigs) versus a species that is free of the disease (goat). Controlled laboratory study. Distal femora from cadavers of juvenile humans (n = 5), pigs (n = 3), and goats (n = 3) were scanned in a 9.4-T MRI scanner using susceptibility-weighted imaging. Three-dimensional reconstructions were created, and minimum intensity projections were calculated in 3 planes to enhance visualization of the vascular architecture. Susceptibility-weighted imaging allowed clear visualization of the epiphyseal vasculature in all species. Vascular architecture, with vessels primarily arising from the perichondrium, was similar in humans and pigs, which are predisposed to osteochondrosis/osteochondritis dissecans, and was starkly different from that present in goats, a species in which there are no reports of osteochondrosis/osteochondritis dissecans. Furthermore, vessels in the distal femoral predilection site disappeared with age in humans in a pattern similar to that reported previously in pigs. Nearly identical vascular architecture at the shared primary predilection site of osteochondrosis/osteochondritis dissecans in the femoral condyles in human beings and pigs suggests that vascular failure, which is known to be central to the pathogenesis of this disease in pigs, may also play a

  3. EcoIP: An Open Source Image Analysis Toolkit to Identify Different Stages of Plant Phenology for Multiple Species with Pan-Tilt-Zoom Cameras

    DEFF Research Database (Denmark)

    Granados, Joel; Bonnet, Philippe

    2013-01-01

    Because of the increased number of cameras employed in environmental sensing and the tremendous image output they produce, we have created a flexible, open-source software solution called EcoIP to help automatically determine different phenophases for different species from digital image sequence...

  4. Sex differences in exercise motivation and body-image satisfaction among college students.

    Science.gov (United States)

    Smith, B L; Handley, P; Eldredge, D A

    1998-04-01

    The current study was an expansion of one by Cash, Novy, and Grant in 1994, in which responses of 101 female nursing students were examined for associations between reasons for exercise, frequency of exercise, and body-image satisfaction. In the current study, 78 male and 100 female undergraduates between the ages of 18 and 25 years (M = 21.2, SD = 1.9) from various majors completed a demographics/frequency of exercise survey, two body-assessment inventories, and the Reasons for Exercise Inventory of Silberstein, Striegel-Moore, Timko, and Rodin. Contrary to Cash, et al.'s findings, only health and fitness reasons were predictive of women's frequency of exercise, and women's dissatisfaction with specific bodily attributes was not significantly related to any reasons for exercising; however, like women in their sample, the current students who experienced more situational body dissatisfaction exercised for appearance and weight control. Sex comparisons indicated similar dissatisfaction with specific bodily attributes among men and women, but values were not significantly associated with any reasons for exercising. Women reported higher situational body dissatisfaction and exercising for appearance-related reasons more than men. Current participants may represent a more diverse group than previously tested, and the inventory's factor structure may not be generalizable to men and women.

  5. Enzyme-Mediated Modification of Single-Domain Antibodies for Imaging Modalities with Different Characteristics.

    Science.gov (United States)

    Rashidian, Mohammad; Wang, Lu; Edens, Jerre G; Jacobsen, Johanne T; Hossain, Intekhab; Wang, Qifan; Victora, Gabriel D; Vasdev, Neil; Ploegh, Hidde; Liang, Steven H

    2016-01-11

    Antibodies are currently the fastest-growing class of therapeutics. Although naked antibodies have proven valuable as pharmaceutical agents, they have some limitations, such as low tissue penetration and a long circulatory half-life. They have been conjugated to toxic payloads, PEGs, or radioisotopes to increase and optimize their therapeutic efficacy. Although nonspecific conjugation is suitable for most in vitro applications, it has become evident that site specifically modified antibodies may have advantages for in vivo applications. Herein we describe a novel approach in which the antibody fragment is tagged with two handles: one for the introduction of a fluorophore or (18)F isotope, and the second for further modification of the fragment with a PEG moiety or a second antibody fragment to tune its circulatory half-life or its avidity. Such constructs, which recognize Class II MHC products and CD11b, showed high avidity and specificity. They were used to image cancers and could detect small tumors. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Sex differences in Alzheimer risk: Brain imaging of endocrine vs chronologic aging.

    Science.gov (United States)

    Mosconi, Lisa; Berti, Valentina; Quinn, Crystal; McHugh, Pauline; Petrongolo, Gabriella; Varsavsky, Isabella; Osorio, Ricardo S; Pupi, Alberto; Vallabhajosula, Shankar; Isaacson, Richard S; de Leon, Mony J; Brinton, Roberta Diaz

    2017-09-26

    This observational multimodality brain imaging study investigates emergence of endophenotypes of late-onset Alzheimer disease (AD) risk during endocrine transition states in a cohort of clinically and cognitively normal women and age-matched men. Forty-two 40- to 60-year-old cognitively normal women (15 asymptomatic perimenopausal by age [CNT], 13 perimenopausal [PERI], and 14 postmenopausal [MENO]) and 18 age- and education-matched men were examined. All patients had volumetric MRI, (18)F-fluoro-2-deoxyglucose (FDG)-PET (glucose metabolism), and Pittsburgh compound B-PET scans (β-amyloid [Aβ] deposition, a hallmark of AD pathology). As expected, the MENO group was older than the PERI and CNT groups. Otherwise, groups were comparable on clinical and neuropsychological measures and APOE4 distribution. Compared to CNT women and to men, and controlling for age, PERI and MENO groups exhibited increased indicators of AD endophenotype, including hypometabolism, increased Aβ deposition, and reduced gray and white matter volumes in AD-vulnerable regions (p endocrine transition of perimenopause. These data indicate that the optimal window of opportunity for therapeutic intervention in women is early in the endocrine aging process. © 2017 American Academy of Neurology.

  7. Note on difference spectra for fast extraction of global image information.

    CSIR Research Space (South Africa)

    Van Wyk, BJ

    2007-06-01

    Full Text Available FOR FAST EXTRACTION OF GLOBAL IMAGE INFORMATION. B.J van Wyk* M.A. van Wyk* and F. van den Bergh** * c29c55c48c51c46c4bc03 c36c52c58c57c4bc03 c24c49c55c4cc46c44c51c03 c37c48c46c4bc51c4cc46c44c4fc03 c2cc51c56c57c4cc57c58c57c48c03 c4cc51c03 c28c4fc48c...46c57c55c52c51c4cc46c56c03 c0bc29cb6c36c24c37c2cc28c0cc03 c44c57c03 c57c4bc48c03 c37c56c4bc5ac44c51c48c03 c38c51c4cc59c48c55c56c4cc57c5cc03 c52c49c03 Technology, Private Bag X680, Pretoria 0001. ** Remote Sensing Research Group, Meraka Institute...

  8. Quantitative image analysis as a tool for Yarrowia lipolytica dimorphic growth evaluation in different culture media.

    Science.gov (United States)

    Braga, A; Mesquita, D P; Amaral, A L; Ferreira, E C; Belo, I

    2016-01-10

    Yarrowia lipolytica, a yeast strain with a huge biotechnological potential, capable to produce metabolites such as γ-decalactone, citric acid, intracellular lipids and enzymes, possesses the ability to change its morphology in response to environmental conditions. In the present study, a quantitative image analysis (QIA) procedure was developed for the identification and quantification of Y. lipolytica W29 and MTLY40-2P strains dimorphic growth, cultivated in batch cultures on hydrophilic (glucose and N-acetylglucosamine (GlcNAc) and hydrophobic (olive oil and castor oil) media. The morphological characterization of yeast cells by QIA techniques revealed that hydrophobic carbon sources, namely castor oil, should be preferred for both strains growth in the yeast single cell morphotype. On the other hand, hydrophilic sugars, namely glucose and GlcNAc caused a dimorphic transition growth towards the hyphae morphotype. Experiments for γ-decalactone production with MTLY40-2P strain in two distinct morphotypes (yeast single cells and hyphae cells) were also performed. The obtained results showed the adequacy of the proposed morphology monitoring tool in relation to each morphotype on the aroma production ability. The present work allowed establishing that QIA techniques can be a valuable tool for the identification of the best culture conditions for industrial processes implementation. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Machine learning techniques for breast cancer computer aided diagnosis using different image modalities: A systematic review.

    Science.gov (United States)

    Yassin, Nisreen I R; Omran, Shaimaa; El Houby, Enas M F; Allam, Hemat

    2018-03-01

    The high incidence of breast cancer in women has increased significantly in the recent years. Physician experience of diagnosing and detecting breast cancer can be assisted by using some computerized features extraction and classification algorithms. This paper presents the conduction and results of a systematic review (SR) that aims to investigate the state of the art regarding the computer aided diagnosis/detection (CAD) systems for breast cancer. The SR was conducted using a comprehensive selection of scientific databases as reference sources, allowing access to diverse publications in the field. The scientific databases used are Springer Link (SL), Science Direct (SD), IEEE Xplore Digital Library, and PubMed. Inclusion and exclusion criteria were defined and applied to each retrieved work to select those of interest. From 320 studies retrieved, 154 studies were included. However, the scope of this research is limited to scientific and academic works and excludes commercial interests. This survey provides a general analysis of the current status of CAD systems according to the used image modalities and the machine learning based classifiers. Potential research studies have been discussed to create a more objective and efficient CAD systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Exploring gender differences in body image, eating pathology, and sexual harassment.

    Science.gov (United States)

    Buchanan, Nicole T; Bluestein, Brooke M; Nappa, Alexa C; Woods, Krystle C; Depatie, Melissa M

    2013-06-01

    This study examines the relationship between body image (weight/shape concerns), eating pathology, and sexual harassment among men and women (N=2446). Hierarchical regressions controlling for depression revealed main effects of gender such that women reported greater weight/shape concerns, eating pathology, dietary restraint, eating concerns, and binge eating compared to men. Main effects for sexual harassment indicated that as harassment increased, participants reported increased weight/shape concerns, eating pathology, dietary restraint, eating concerns, binge eating, and compensatory behaviors. There were small but significant interactions between gender and harassment for eating pathology total score (which included each of the domains listed above), weight/shape concerns, dietary restraint, and eating concerns such that the relationship between increased harassment and increased pathology was stronger for women compared to men. The largest interaction was found for compensatory behaviors, such that while women and men's scores both increased as harassment increased, the relationship was stronger for men. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Adolescents' perceptions of cigarette brand image: does plain packaging make a difference?

    Science.gov (United States)

    Germain, Daniella; Wakefield, Melanie A; Durkin, Sarah J

    2010-04-01

    To examine the effect of plain packaging on adolescents' perceptions of cigarette packs, attributes of smokers, and expectations of cigarette taste, and to identify the effect of increasing the size of pictorial health warnings on appraisal of plain packs. We used a 5 (degree of plain packaging and graphic health warning)x 3 (brand type) between-subjects experimental design, using a Web-based methodology to expose adolescents to one randomly selected cigarette pack, during which respondents completed ratings. When brand elements such as color, branded fonts, and imagery were progressively removed from cigarette packs, adolescents perceived packs to be less appealing, rated attributes of a typical smoker of the pack less positively, and had more negative expectations of cigarette taste. Pack appeal was reduced even further when the size of the pictorial health warning on the most plain pack was increased from 30% to 80% of the pack face, with this effect apparent among susceptible nonsmokers, experimenters, and established smokers. Removing as much brand information from cigarette packs as possible is likely to reduce positive cigarette brand image associations among adolescents. By additionally increasing the size of pictorial health warnings, positive pack perceptions of those who are at greater risk of becoming regular addicted adult smokers are most likely to be reduced. Copyright 2010 Society for Adolescent Medicine. Published by Elsevier Inc. All rights reserved.

  12. Individual differences in the processing of smoking-cessation video messages: An imaging genetics study.

    Science.gov (United States)

    Shi, Zhenhao; Wang, An-Li; Aronowitz, Catherine A; Romer, Daniel; Langleben, Daniel D

    2017-09-01

    Studies testing the benefits of enriching smoking-cessation video ads with attention-grabbing sensory features have yielded variable results. Dopamine transporter gene (DAT1) has been implicated in attention deficits. We hypothesized that DAT1 polymorphism is partially responsible for this variability. Using functional magnetic resonance imaging, we examined brain responses to videos high or low in attention-grabbing features, indexed by "message sensation value" (MSV), in 53 smokers genotyped for DAT1. Compared to other smokers, 10/10 homozygotes showed greater neural response to High- vs. Low-MSV smoking-cessation videos in two a priori regions of interest: the right temporoparietal junction and the right ventrolateral prefrontal cortex. These regions are known to underlie stimulus-driven attentional processing. Exploratory analysis showed that the right temporoparietal response positively predicted follow-up smoking behavior indexed by urine cotinine. Our findings suggest that responses to attention-grabbing features in smoking-cessation messages is affected by the DAT1 genotype. Copyright © 2017. Published by Elsevier B.V.

  13. Discrimination of different brain metastases and primary CNS lymphomas using morphologic criteria and diffusion tensor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bette, S.; Wiestler, B.; Huber, T.; Boeckh-Behrens, T.; Zimmer, C.; Kirschke, J. [Technical University Munich, Klinikum rechts der Isar (Germany). Dept. of Neuroradiology; Delbridge, C. [Technical University Munich, Klinikum rechts der Isar (Germany). Dept. of Neuropathology; Meyer, B.; Gempt, J. [Technical University Munich, Klinikum rechts der Isar (Germany). Dept. of Neurosurgery

    2016-12-15

    Brain metastases are a common complication of cancer and occur in about 15-40% of patients with malignancies. The aim of this retrospective study was to differentiate between metastases from different primary tumors/CNS lymphyomas using morphologic criteria, fractional anisotropy (FA) and apparent diffusion coefficient (ADC). Morphologic criteria such as hemorrhage, cysts, pattern of contrast enhancement and location were reported in 200 consecutive patients with brain metastases/primary CNS lymphomas. FA and ADC values were measured in regions of interest (ROIs) placed in the contrast-enhancing tumor part, the necrosis and the non-enhancing peritumoral region (NEPTR). Differences between histopathological subtypes of metastases were analyzed using non-parametric tests, decision trees and hierarchical clustering analysis. Significant differences were found in morphologic criteria such as hemorrhage or pattern of contrast enhancement. In diffusion measurements, significant differences between the different tumor entities were only found in ADC analyzed in the contrast-enhancing tumor part. Among single tumor entities, primary CNS lymphomas showed significantly lower median ADC values in the contrast-enhancing tumor part (ADC{sub lymphoma} 0.92 [0.83-1.07] vs. ADC{sub no} {sub lymphoma} 1.35 [1.10-1.64] P=0.001). Further differentiation between types of metastases was not possible using FA and ADC. There were morphologic differences among the main subtypes of brain metastases/CNS lymphomas. However, due to a high variability of common types of metastases and low specificity, prospective differentiation remained challenging. DTI including FA and ADC was not a reliable tool for differentiation between different histopathological subtypes of brain metastases except for CNS lymphomas showing lower ADC values. Biopsy, surgery and staging remain essential for diagnosis.

  14. Conversion of mammographic images to appear with the noise and sharpness characteristics of a different detector and x-ray system.

    Science.gov (United States)

    Mackenzie, Alistair; Dance, David R; Workman, Adam; Yip, Mary; Wells, Kevin; Young, Kenneth C

    2012-05-01

    Undertaking observer studies to compare imaging technology using clinical radiological images is challenging due to patient variability. To achieve a significant result, a large number of patients would be required to compare cancer detection rates for different image detectors and systems. The aim of this work was to create a methodology where only one set of images is collected on one particular imaging system. These images are then converted to appear as if they had been acquired on a different detector and x-ray system. Therefore, the effect of a wide range of digital detectors on cancer detection or diagnosis can be examined without the need for multiple patient exposures. Three detectors and x-ray systems [Hologic Selenia (ASE), GE Essential (CSI), Carestream CR (CR)] were characterized in terms of signal transfer properties, noise power spectra (NPS), modulation transfer function, and grid properties. The contributions of the three noise sources (electronic, quantum, and structure noise) to the NPS were calculated by fitting a quadratic polynomial at each spatial frequency of the NPS against air kerma. A methodology was developed to degrade the images to have the characteristics of a different (target) imaging system. The simulated images were created by first linearizing the original images such that the pixel values were equivalent to the air kerma incident at the detector. The linearized image was then blurred to match the sharpness characteristics of the target detector. Noise was then added to the blurred image to correct for differences between the detectors and any required change in dose. The electronic, quantum, and structure noise were added appropriate to the air kerma selected for the simulated image and thus ensuring that the noise in the simulated image had the same magnitude and correlation as the target image. A correction was also made for differences in primary grid transmission, scatter, and veiling glare. The method was validated by

  15. Conversion of mammographic images to appear with the noise and sharpness characteristics of a different detector and x-ray system

    Energy Technology Data Exchange (ETDEWEB)

    Mackenzie, Alistair; Dance, David R.; Workman, Adam; Yip, Mary; Wells, Kevin; Young, Kenneth C. [National Coordinating Centre for the Physics of Mammography, Royal Surrey County Hospital, Guildford, GU2 7XX, United Kingdom and Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Northern Ireland Regional Medical Physics Service, Forster Green Hospital, Belfast, BT8 4HD (United Kingdom); Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Centre for Vision, Speech and Signal Processing, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH (United Kingdom); National Coordinating Centre for the Physics of Mammography, Royal Surrey County Hospital, Guildford, GU2 7XX, United Kingdom and Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom)

    2012-05-15

    Purpose: Undertaking observer studies to compare imaging technology using clinical radiological images is challenging due to patient variability. To achieve a significant result, a large number of patients would be required to compare cancer detection rates for different image detectors and systems. The aim of this work was to create a methodology where only one set of images is collected on one particular imaging system. These images are then converted to appear as if they had been acquired on a different detector and x-ray system. Therefore, the effect of a wide range of digital detectors on cancer detection or diagnosis can be examined without the need for multiple patient exposures. Methods: Three detectors and x-ray systems [Hologic Selenia (ASE), GE Essential (CSI), Carestream CR (CR)] were characterized in terms of signal transfer properties, noise power spectra (NPS), modulation transfer function, and grid properties. The contributions of the three noise sources (electronic, quantum, and structure noise) to the NPS were calculated by fitting a quadratic polynomial at each spatial frequency of the NPS against air kerma. A methodology was developed to degrade the images to have the characteristics of a different (target) imaging system. The simulated images were created by first linearizing the original images such that the pixel values were equivalent to the air kerma incident at the detector. The linearized image was then blurred to match the sharpness characteristics of the target detector. Noise was then added to the blurred image to correct for differences between the detectors and any required change in dose. The electronic, quantum, and structure noise were added appropriate to the air kerma selected for the simulated image and thus ensuring that the noise in the simulated image had the same magnitude and correlation as the target image. A correction was also made for differences in primary grid transmission, scatter, and veiling glare. The method was

  16. VECTOR DATA DIFFERENCES IDENTIFICATION IN THE THEMATIC PROCESSING OF SPACE IMAGES

    Directory of Open Access Journals (Sweden)

    A. A. Zalatoi

    2017-01-01

    Full Text Available The problem of differences identifying in vector graphics data packages and how to solve it is considered. Map information and vectorized data of remote sensing of Earth are sources of vector data in the article. The aim is to design a method for detecting differences in vector data packages, providing reliable results for updating map and monitoring areas tasks. Research and development is done by mathematical modeling of the task in MATLAB. The article provides developed method for solving the task and results of its application for finding differences between two vector data packages, obtained from the target information of remote sensing of the Earth, and/or vector layers of digital district map. This method allows you to automate the process and reduce the time of thematic analysis of cosmic information, obtained from remote sensing of the Earth for topographic mapping and monitoring areas.

  17. Body perception: do parents, their children, and their children's physicians perceive body image differently?

    Science.gov (United States)

    Chaimovitz, R; Issenman, R; Moffat, T; Persad, R

    2008-07-01

    To compare children's, parents' and physicians' perceptions of children's body size. We administered a structured questionnaire of body size perception using a descriptive Likert scale keyed to body image figures to children ages 12 to 18 years. The same scale was given to parents of children ages 5 to 18 years. The sample consisted of 91 children and their parents being seen in the Pediatric Gastroenterology Clinic for concerns unrelated to overweight. Weight and height of the children were measured, and body mass index (BMI) was calculated. The children's BMI percentiles were categorized as underweight (scale and indicated the figure that most accurately represented the patient without reference to BMI standards. Accuracy of the patients', parents', and doctors' estimates were statistically compared. The sample population consisted of 6.4% underweight, 70.5% normal weight, 7.7% overweight, and 15.4% obese. Forty-four percent of parents underestimated children's body size using word descriptions and 47% underestimated using figures. Forty percent of the children underestimated their own body size using descriptions and 43% underestimated using figures. The physicians in this study had a higher percentage of correct estimates; however, they underestimated 33% of the patients using both word descriptions and figures. Some obese children were not recognized, and several average children were perceived as underweight. Many children underestimated their degree of overweight. Their parents and even their attending physicians shared this misperception. This study demonstrates the need to further educate physicians to recognize obesity and overweight so that they can counsel children and their families.

  18. Changes of brain metabolite concentrations during maturation in different brain regions measured by chemical shift imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bueltmann, Eva; Lanfermann, Heinrich [Hannover Medical School, Institute of Diagnostic and Interventional Neuroradiology, Hannover (Germany); Naegele, Thomas [University of Tuebingen, Department of Diagnostic and Interventional Neuroradiology, Radiological University Hospital, Tuebingen (Germany); Klose, Uwe [University of Tuebingen, Section of Experimental MR of the CNS, Department of Neuroradiology, Radiological University Hospital, Tuebingen (Germany)

    2017-01-15

    We examined the effect of maturation on the regional distribution of brain metabolite concentrations using multivoxel chemical shift imaging. From our pool of pediatric MRI examinations, we retrospectively selected patients showing a normal cerebral MRI scan or no pathologic signal abnormalities at the level of the two-dimensional 1H MRS-CSI sequence and an age-appropriate global neurological development, except for focal neurological deficits. Seventy-one patients (4.5 months-20 years) were identified. Using LC Model, spectra were evaluated from voxels in the white matter, caudate head, and corpus callosum. The concentration of total N-acetylaspartate increased in all regions during infancy and childhood except in the right caudate head where it remained constant. The concentration of total creatine decreased in the caudate nucleus and splenium and minimally in the frontal white matter and genu. It remained largely constant in the parietal white matter. The concentration of choline-containing compounds had the tendency to decrease in all regions except in the parietal white matter where it remained constant. The concentration of myoinositol decreased slightly in the splenium and right frontal white matter, remained constant on the left side and in the caudate nucleus, and rose slightly in the parietal white matter and genu. CSI determined metabolite concentrations in multiple cerebral regions during routine MRI. The obtained data will be helpful in future pediatric CSI measurements deciding whether the ratios of the main metabolites are within the range of normal values or have to be considered as probably pathologic. (orig.)

  19. Differences in functional MR imaging activation patterns associated with confrontation naming and responsive naming.

    Science.gov (United States)

    Tomaszewki Farias, Sarah; Harrington, Gregory; Broomand, Catherine; Seyal, Maysud

    2005-01-01

    Direct cortical stimulation studies suggest that responsive naming is more widely distributed within the temporal lobe than confrontation naming and involves anterior temporal regions typically resected in a standard temporal lobectomy. The aim of the current study was to further demonstrate the anatomic dissociation between confrontation and responsive naming by using functional MR imaging (fMRI). Twenty participants underwent fMRI while performing either a confrontation or responsive naming task. Regions of interest were identified within the anterior and posterior temporal lobe. Responsive naming produced more activation than confrontation naming within the dominant temporal lobe, with activation extending into the temporal pole. Activation in the dominant temporal lobe associated with responsive naming was observed in the superior, middle, and inferior temporal gyri but was limited to the middle temporal gyrus for confrontation naming. Although both naming tasks produced activation within the posterior temporal region of interest in all participants, responsive and confrontation naming produced activation within the anterior temporal region of interest in 90% versus 60% of the sample, respectively. Areas of the dominant hemisphere activated by both tasks included parts of the middle occipital and middle temporal gyri, inferior frontal lobe, and hippocampus, among others. Findings are consistent with cortical stimulation studies and suggest that responsive naming produces more widespread activation within the temporal lobe compared with confrontation naming. The activation more often included anterior temporal regions during responsive naming as compared with confrontation naming. In clinical cases where the functional assessment of the temporal lobe-particularly the anterior regions-is important, the current results suggest responsive naming should be a useful fMRI paradigm and may ultimately help predict the risk of postsurgical language changes.

  20. No wilderness for immigrants: Cultural differences in images of nature and landscape preferences

    NARCIS (Netherlands)

    Buijs, A.E.; Elands, B.H.M.; Langers, F.

    2009-01-01

    Despite the growing cultural diversity in many European countries, nature recreation is still a very ¿white¿ activity. Immigrants hardly ever visit non-urban green areas. Prior research has suggested that different perceptions of nature and landscape may be related to this limited use. Based on 618

  1. Adult Age, Gender, and Race Group Differences in Images of Aging

    Science.gov (United States)

    Foos, Paul W.; Clark, M. Cherie; Terrell, Debra F.

    2006-01-01

    Younger and older African American and Caucasian American adults, who were matched by age ("M" age = 40.63 years), completed a survey on perceptions of aging and subjective age. The 2 groups did not differ in the age they considered someone to be old ("M" age = 74.5 years). However, when asked which age was the happiest age, African Americans…

  2. Does Imaging Modality Used For Percutaneous Renal Access Make a Difference?

    DEFF Research Database (Denmark)

    Andonian, Sero; Scoffone, Cesare; Louie, Michael K

    2013-01-01

    in 2853 patients (86.3%). Comparisons were performed on a matched sample with 453 patients in each group. Frequency and pattern of Clavien complications did not differ between groups (P =.333). However, post-operative hemorrhage and transfusions were significantly higher in the fluoroscopy group: 6.0 vs...

  3. Improving spatial localization in MEG inverse imaging by leveraging intersubject anatomical differences

    Directory of Open Access Journals (Sweden)

    Eric eLarson

    2014-10-01

    Full Text Available Modern neuroimaging techniques enable non-invasive observation of ongoing neural processing, with magnetoencephalography (MEG in particular providing direct measurement of neural activity with millisecond time resolution. However, accurately mapping measured MEG sensor readings onto the underlying source neural structures remains an active area of research. This so-called inverse problem is ill posed, and poses a challenge for source estimation that is often cited as a drawback limiting MEG data interpretation. However, anatomically constrained MEG localization estimates may be more accurate than commonly believed. Here we hypothesize that, by combining anatomically constrained inverse estimates across subjects, the spatial uncertainty of MEG source localization can be mitigated. Specifically, we argue that differences in subject brain geometry yield differences in point-spread functions, resulting in improved spatial localization across subjects. To test this, we use standard methods to combine subject anatomical MRI scans with coregistration information to obtain an accurate forward (physical solution, modeling the MEG sensor data resulting from brain activity originating from different cortical locations. Using a linear minimum-norm inverse to localize this brain activity, we demonstrate that a substantial increase in the spatial accuracy of MEG source localization can result from combining data from subjects with differing brain geometry. This improvement may be enabled by an increase in the amount of available spatial information in MEG data as measurements from different subjects are combined. This approach becomes more important in the face of practical issues of coregistration errors and potential noise sources, where we observe even larger improvements in localization when combining data across subjects. Finally, we use a simple auditory N100(m localization task to show how this effect can influence localization using a recorded neural

  4. Real-time prediction of pre-cooked Japanese sausage color with different storage days using hyperspectral imaging.

    Science.gov (United States)

    Feng, Chao-Hui; Makino, Yoshio; Yoshimura, Masatoshi; Rodríguez-Pulido, Francisco J

    2017-10-14

    Redness can greatly influence the freshness of sausages. A precise, rapid and noncontact analytical method or tool is needed to quantify the color. Hyperspectral imaging (HSI) is an emerging technique that integrates spectroscopy and imaging to obtain the spectral and spatial information simultaneously. In the present study, the redness of cooked sausages stored up to 57 days was predicted using HSI in tandem with multivariate data analysis. The mean spectra of the sausages were extracted from the hyperspectral images. Partial least squares regression (PLSR) and forward stepwise multiple regression (FSMR) models were used to develop the relavent spectral profiles with the redness of the cooked sausages. Ten important wavelengths were selected based on the regression coefficient values from the PLSR model. The PLSR model established using the full wavelengths presented a good performance, with Rc of 0.934 and a root mean square error of calibration of 0.642 (redness ranged between 14.99 and 21.48). The prediction maps for demonstrating evolution of redness in sausages were developed for the first time using R statistics (R Foundation for Statistical Computing) and Matlab (MathWorks Inc., Natick, MA, USA). HSI combined with PLSR and FSMR can be used to quantify and visualize evolution of sausage redness under different storage days. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  5. Retinal image quality with the different types of intraocular lenses including new idea of the hybrid IOLs

    Science.gov (United States)

    Siedlecki, D.; Zając, M.; Nowak, J.

    2007-07-01

    Cataract is one of the most frequent reasons of blindness all around the world. Its treatment relies on removing the pathologically altered crystalline lens and replacing it with an artificial intraocular lens (IOL). There exists plenty of types of such implants, which differ in the optical materials and designs (shapes). However one of the important features, which is rather overlooked in the development of the intraocular implants is the chromatic aberration and its influence on the retinal image quality. In this study authors try to estimate the influence of the design and optical material of the implant on the retinal image quality in the polychromatic light, taking into consideration several exemplary types of IOLs which are commercially available. Authors also propose the partially achromatized hybrid IOLs, the longitudinal chromatic aberration (LCA)of which reduces the total LCA of the phakic eye to the level of a healthy eye's LCA. Several image characteristics, as the polychromatic Point Spread Function (PSF) and the Modulation Transfer Function (MTF) and the polychromatic encircled energy are estimated. The results of the simulations show the significance of the partial chromatic aberration correction.

  6. Detailed morphological characterisation of Hendra virus infection of different cell types using super-resolution and conventional imaging.

    Science.gov (United States)

    Monaghan, Paul; Green, Diane; Pallister, Jackie; Klein, Reuben; White, John; Williams, Catherine; McMillan, Paul; Tilley, Leann; Lampe, Marko; Hawes, Pippa; Wang, Lin-Fa

    2014-11-27

    Hendra virus (HeV) is a pleomorphic virus belonging to the Paramyxovirus family. Our long-term aim is to understand the process of assembly of HeV virions. As a first step, we sought to determine the most appropriate cell culture system with which to study this process, and then to use this model to define the morphology of the virus and identify the site of assembly by imaging key virus encoded proteins in infected cells. A range of primary cells and immortalised cell lines were infected with HeV, fixed at various time points post-infection, labelled for HeV proteins and imaged by confocal, super-resolution and transmission electron microscopy. Significant differences were noted in viral protein distribution depending on the infected cell type. At 8 hpi HeV G protein was detected in the endoplasmic reticulum and M protein was seen predominantly in the nucleus in all cells tested. At 18 hpi, HeV-infected Vero cells showed M and G proteins throughout the cell and in transmission electron microscope (TEM) sections, in pleomorphic virus-like structures. In HeV infected MDBK, A549 and HeLa cells, HeV M protein was seen predominantly in the nucleus with G protein at the membrane. In HeV-infected primary bovine and porcine aortic endothelial cells and two bat-derived cell lines, HeV M protein was not seen at such high levels in the nucleus at any time point tested (8,12, 18, 24, 48 hpi) but was observed predominantly at the cell surface in a punctate pattern co-localised with G protein. These HeV M and G positive structures were confirmed as round HeV virions by TEM and super-resolution (SR) microscopy. SR imaging demonstrated for the first time sub-virion imaging of paramyxovirus proteins and the respective localisation of HeV G, M and N proteins within virions. These findings provide novel insights into the structure of HeV and show that for HeV imaging studies the choice of tissue culture cells may affect the experimental results. The results also indicate that He

  7. Relationship between anxiety level and radiological investigation. Comparison among different diagnostic imaging exams in a prospective single-center study.

    Science.gov (United States)

    Lo Re, Giuseppe; De Luca, Rossella; Muscarneri, Filippa; Dorangricchia, Patrizia; Picone, Dario; Vernuccio, Federica; Salerno, Sergio; La Tona, Giuseppe; Pinto, Antonio; Midiri, Massimo; Russo, Antonio; Lagalla, Roberto; Cicero, Giuseppe

    2016-10-01

    Every patient could feel anxious when he waits in a radiological department to undergo diagnostic exams. The aim of our study is to evaluate the impact of the radiological exams on patient anxiety. We evaluated 343 patients (mean age 54.83 years) who underwent different types of diagnostic exams in the Department of Diagnostic Imaging at our Hospital from April 2013 to August 2014. We administered to patients the State and Trait Anxiety Inventory Test, which detected with high sensitivity both state anxiety and trait anxiety. A team of clinical psychologists and radiologists evaluated the scores obtained. 83 out of 343 patients were excluded because refused to file the questionnaire. 31 % of the patients were submitted to MR, 18 % to breast imaging, 10 % to X-ray, 22 % Computer Tomography and 19 % to ultrasound, as previously described. 41 % of patients were submitted to the examination because of an oncologic disease, while 59 % because of non-oncological disease. Therefore, it was found that high levels of anxiety were present in most (about 91 %) of the patients and the scores varied according to the imaging examination and to the examination's reason: anxiety level was higher in non-oncological patients (54 %) and in patients waiting to undergo to MRI exams (29 %). Our data suggest that the diagnostic exams are stressful events for the patient, also in non-oncological patients. So, it is important to adequate the radiological staff to receive the patient, to inform him and perform exams with emotive involvement with a targeted education. Also, further studies are needed to evaluate the anxiety level and the quality of the images, because the anxiety can result in a somatic disorder with hyperactivity of the autonomic nervous system which may affect the patient's physical examination, causing problems in the evaluation of radiological images making to non-cooperative patient. MRI imaging is the examination that more of all led to an anxious state of

  8. Functional imaging of brain responses to different outcomes of hypothesis testing: revealed in a category induction task.

    Science.gov (United States)

    Li, Fuhong; Cao, Bihua; Luo, Yuejia; Lei, Yi; Li, Hong

    2013-02-01

    Functional magnetic resonance imaging (fMRI) was used to examine differences in brain activation that occur when a person receives the different outcomes of hypothesis testing (HT). Participants were provided with a series of images of batteries and were asked to learn a rule governing what kinds of batteries were charged. Within each trial, the first two charged batteries were sequentially displayed, and participants would generate a preliminary hypothesis based on the perceptual comparison. Next, a third battery that served to strengthen, reject, or was irrelevant to the preliminary hypothesis was displayed. The fMRI results revealed that (1) no significant differences in brain activation were found between the 2 hypothesis-maintain conditions (i.e., strengthen and irrelevant conditions); and (2) compared with the hypothesis-maintain conditions, the hypothesis-reject condition activated the left medial frontal cortex, bilateral putamen, left parietal cortex, and right cerebellum. These findings are discussed in terms of the neural correlates of the subcomponents of HT and working memory manipulation. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Beyond complications: Comparison of procedural differences and diagnostic success between nurse practitioners and radiologists performing image-guided renal biopsies.

    Science.gov (United States)

    Nandwana, Sadhna B; Walls, Deborah G; Ibraheem, Oluwayemisi; Murphy, Frederick; Tridandapani, Srini; Cox, Kelly

    2016-10-01

    Radiology-trained nurse practitioners (NPs) may perform image-guided medical renal biopsies with computed tomography (CT). This study evaluates the procedural differences and diagnostic success between biopsies performed by NPs compared to radiologists. A retrospective study was performed on patients who underwent nontargeted, CT-guided renal biopsy between 2009 and 2014. Provider type (NP or radiologist), number of core specimens obtained, sedation medication dose, CT dose index (CTDI), and diagnostic success were recorded. Categorical and continuous variables were analyzed using χ 2 and Student's two-tailed t-test, respectively, comparing NPs with radiologists. A total of 386 patients were included; radiologists performed 215 biopsies and NPs performed 171 biopsies. There was no significant difference in diagnostic success, amount of tissue harvested (number of cores), radiation dose, or sedation dosage between NPs and radiologists performing CT-guided renal biopsies. Only 4% were nondiagnostic (n = 7, radiologists; n = 9, NPs; p = .325). Overall mean number of cores obtained was 3.7, mean CTDI was 176.5 mGy, mean fentanyl dose was 86.3 μg, and mean midazolam was dose 1.54 mg without a statistically significant difference between provider types. NPs perform image-guided medical renal biopsies in a similar fashion to radiologists with respect to diagnostic success, amount of tissue harvested, total radiation dose exposure, and administration of sedation. ©2016 American Association of Nurse Practitioners.

  10. Effects of Spectral Band Differences between Landsat 8 Operational Land Imager (OLI) and Sentinel 2A Multispectral Instrument (MSI)

    Science.gov (United States)

    Micijevic, E.; Haque, M. O.

    2015-12-01

    In satellite remote sensing, Landsat sensors are recognized for providing well calibrated satellite images for over four decades. This image data set provides an important contribution to detection and temporal analysis of land changes. Landsat 8 (L8), the latest satellite of the Landsat series, was designed to continue its legacy as well as to embrace advanced technology and satisfy the demand of the broader scientific community. Sentinel 2A (S2A), a European satellite launched in June 2015, is designed to keep data continuity of Landsat and SPOT like satellites. The S2A MSI sensor is equipped with spectral bands similar to L8 OLI and includes some additional ones. Compared to L8 OLI, green and near infrared MSI bands have narrower bandwidths, whereas coastal-aerosol (CA) and cirrus have larger bandwidths. The blue and red MSI bands cover higher wavelengths than the matching OLI bands. Although the spectral band differences are not large, their combination with the spectral signature of a studied target can largely affect the Top Of Atmosphere (TOA) reflectance seen by the sensors. This study investigates the effect of spectral band differences between S2A MSI and L8 OLI sensors. The differences in spectral bands between sensors can be assessed by calculating Spectral Band Adjustment Factors (SBAF). For radiometric calibration purposes, the SBAFs for the calibration test site are used to bring the two sensors to the same radiometric scale. However, the SBAFs are target dependent and different sensors calibrated to the same radiometric scale will (correctly!) measure different reflectance for the same target. Thus, when multiple sensors are used to study a given target, the sensor responses need to be adjusted using SBAFs specific to that target. Comparison of the SBAFs for S2A MSI and L8 OLI based on various vegetation spectral profiles revealed variations in radiometric responses as high as 15%. Depending on target under study, these differences could be even

  11. Diffusion-weighted magnetic resonance imaging during radiotherapy of locally advanced cervical cancer - treatment response assessment using different segmentation methods

    DEFF Research Database (Denmark)

    Haack, Søren; Tanderup, Kari; Kallehauge, Jesper Folsted

    2015-01-01

    .01), and the volumes changed significantly during treatment (p clustering (mean± sd: 0...... into external beam RT (WK2RT) and one week prior to brachytherapy (PREBT). Volumes on DW-MRI were segmented using three semi-automatic segmentation methods: "cluster analysis", "relative signal intensity (SD4)" and "region growing". Segmented volumes were compared to the gross tumor volume (GTV) identified on T.......52 ± 0.3). There was no significant difference in mean ADC value compared at same treatment time. Mean tumor ADC value increased significantly (p treatment time. CONCLUSION: Among the three semi-automatic segmentations of hyper-intense intensities on DW-MR images...

  12. In vivo comparative study of hydroxyapatite labeled with different radioisotopes: evaluation of the scintigraphic images

    Energy Technology Data Exchange (ETDEWEB)

    Couto, Renata Martinussi; Barboza, Marycel Figols de; Souza, Adriano Aparecido de; Muramoto, Emiko; Mengatti, Jair; Araujo, Elaine Bortoleti de, E-mail: rmcouto@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Radiofarmacia

    2008-07-01

    Rheumatoid arthritis (RA) is a chronic inflammatory disorder of joints that is characterized by the inflammation and proliferation of synovial tissues. Approximately 3% of the adult population in the world is affected by this disease which causes pain, joint immobility and disability. Adyo synovectomy (RSV) is a radiotherapeutic modality where a b--emitting radionuclide is administered locally by intra-articular injection on the form of a colloid or radiolabeled particulate. RSV is a well-accepted therapeutic procedure in inflammatory joint diseases and has been successfully employed for more than 50 years as a viable alternative to surgical and chemical synovectomy in the treatment of RA and other inflammatory arthropathies. There are several radionuclides available for this purpose such as {sup 177}Lu, {sup 90}Y, {sup 153}Sm, {sup 165}Dy, and {sup 166}Ho. Hydroxyapatite (HA) is one of the preferred particulates for this application because it is the major chemical constituent of skeletal bone and it is converted into Ca and PO4 ions in the body. In addition HA is completely eliminated over a period of six weeks. The aim of this work is to compare the in vivo stability of hydroxyapatite labeled with {sup 177}Lu, {sup 90}Y and {sup 153}Sm in order to determine the influence of the radionuclide on biological pattern. In biological studies, 100mL of labeled HAs suspended in normal saline were injected into normal knee joints of Wistar rats and the retention of the activity into the synovium was determined. Labeled particles were also injected by intravenous and intramuscular administration, to verify the biodistribution in the case of an eventual leakage of the products from the joint. Sequential scintigraphic images were acquired from 1 hour to 7 days p.i. after anesthetizing the animals with ketamine. Hydroxyapatite was radiolabeled by all radionuclides with high yield. {sup 177}Lu-HA, {sup 90}Y-HA and {sup 153}Sm-HA were retained in the joint for 7 days, showing

  13. Evaluation of 3 Different Registration Techniques in Image-Guided Bimaxillary Surgery

    OpenAIRE

    Sun, Yi; Luebbers, Heinz-Theo; Agbaje, Jimoh Olubanwo; Schepers, Serge; Vrielinck, Luc; Lambrichts, Ivo; Politis, Constantinus

    2013-01-01

    Perioperative navigation is an upcoming tool in orthognathic surgery. This study aimed to access the feasibility of the technique and to evaluate the success rate of 3 different registration methods-facial surface registration, anatomic landmark-based registration, and template-based registration. The BrainLab navigation system (BrainLab AG, Feldkirchen, Germany) was used as an additional precision tool for 85 patients who underwent bimaxillary orthognathic surgery from February 2010 to June ...

  14. Evaluation of subjective image quality in relation to diagnostic task for cone beam computed tomography with different fields of view.

    Science.gov (United States)

    Lofthag-Hansen, Sara; Thilander-Klang, Anne; Gröndahl, Kerstin

    2011-11-01

    To evaluate subjective image quality for two diagnostic tasks, periapical diagnosis and implant planning, for cone beam computed tomography (CBCT) using different exposure parameters and fields of view (FOVs). Examinations were performed in posterior part of the jaws on a skull phantom with 3D Accuitomo (FOV 3 cm×4 cm) and 3D Accuitomo FPD (FOVs 4 cm×4 cm and 6 cm×6 cm). All combinations of 60, 65, 70, 75, 80 kV and 2, 4, 6, 8, 10 mA with a rotation of 180° and 360° were used. Dose-area product (DAP) value was determined for each combination. The images were presented, displaying the object in axial, cross-sectional and sagittal views, without scanning data in a random order for each FOV and jaw. Seven observers assessed image quality on a six-point rating scale. Intra-observer agreement was good (κw=0.76) and inter-observer agreement moderate (κw=0.52). Stepwise logistic regression showed kV, mA and diagnostic task to be the most important variables. Periapical diagnosis, regardless jaw, required higher exposure parameters compared to implant planning. Implant planning in the lower jaw required higher exposure parameters compared to upper jaw. Overall ranking of FOVs gave 4 cm×4 cm, 6 cm×6 cm followed by 3 cm×4 cm. This study has shown that exposure parameters should be adjusted according to diagnostic task. For this particular CBCT brand a rotation of 180° gave good subjective image quality, hence a substantial dose reduction can be achieved without loss of diagnostic information. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  15. Cost analysis of different protocols for imaging a patient with acute flank pain.

    Science.gov (United States)

    Grisi, G; Stacul, F; Cuttin, R; Rimondini, A; Meduri, S; Dalla Palma, L

    2000-01-01

    The aim of this study was to analyse the costs of different diagnostic approaches to patients with acute flank pain. Four different diagnostic approaches were considered: (a) spiral CT without contrast medium (CM); (b) plain film, ultrasonography (US) and intravenous urography (IVU)--the latter procedure is used in our department in cases still unsolved following the former investigations (28% in our experience); (c) plain film, US and spiral CT without CM (as an alternative to IVU in 28% of cases); and (d) IVU. The cost of each procedure in a university hospital was calculated, following analysis of the differential costs of each investigation (equipment, depreciation and maintenance costs, related materials and services, radiologists, radiographers, nurses) and their common costs (auxiliary personnel and indirect internal costs). Finally, we calculated the full cost of each procedure and applied it to the different diagnostic approaches. The full cost of each approach was: (a) spiral CT without CM = 74 Euro; (b) plain film, US and IVU (28%) = 66.89 Euro; (c) plain film, US and spiral CT without CM (28%) = 64.93 Euro; (d) IVU = 80.90 Euro. Intravenous urography alone or in unsolved cases is not to be considered because it provides higher costs and worse diagnostic results, whereas X-ray dose to patient is almost equal between IVU and spiral CT. Spiral CT integrated to plain film and US in unsolved cases could be preferred because of lower cost and dose to patient, though reaching a diagnostic conclusion may take longer than an immediate spiral CT.

  16. Using susceptibility-weighted images to quantify iron deposition differences in amnestic mild cognitive impairment and Alzheimer's disease.

    Science.gov (United States)

    Wang, Dan; Zhu, Dan; Wei, Xiao-Er; Li, Yue-Hua; Li, Wen-Bin

    2013-01-01

    To quantify iron deposition in Alzheimer's disease (AD), amnestic mild cognitive impairment (aMCI), and control individuals using susceptibility weighted imaging (SWI). Sixty participants (22 aMCI, 20 AD, 18 normal controls) underwent conventional magnetic resonance imaging (MRI) and SWI using axial/oblique coronal sequences. Phase images were used to calculate bilateral iron deposition in 18 regions of interest (ROI). The radian angle value was calculated and compared between the three participant groups. The difference in radian angle value was significant between the aMCI and control groups in the left (L)-hippocampus, L-head of the caudate nucleus, R-lenticular nucleus, L-lenticular nucleus (P =0.02239, radian angle value was significant between the AD and aMCI groups in the R-cerebellar hemisphere, L-cerebellar hemisphere, R-hippocampus, L-hippocampus, R-red nucleus, R-thalamus, L-thalamus, and splenium of corpus callosum (P =0.02754, 0.01839, 0.00934, 0.04316, 0.02472, 0.00152, <0.001, 0.01448, respectively). Pearson correlation coefficients of the Mini-Mental State Examination score were all significant for the bilateral cerebellar hemisphere, hippocampus, red nucleus, lenticular nucleus, thalamus, R-head of the caudate nucleus, and splenium of corpus callosum. Iron deposition in the hippocampus, head of the caudate nucleuslenticular nucleus, and thalamus are significantly different between individuals with aMCI, AD, and controls. The thalamus is a particularly sensitive area. Using SWI to quantify the iron deposition is a useful tool in detecting aMCI and AD.

  17. Differences in psychological traits between lingual and labial orthodontic patients: perfectionism, body image, and the impact of dental esthetics.

    Science.gov (United States)

    Bellot-Arcís, Carlos; Ferrer-Molina, Marcela; Carrasco-Tornero, Ángel; Montiel-Company, José María; Almerich-Silla, José Manuel

    2015-01-01

    To examine some of the patients' psychological traits in relation to their levels of perfectionism and their body image, and to discover whether these differ between lingual and labial orthodontic patients. A cross-sectional study was designed with a consecutive sample of 80 patients attending a private orthodontic office. Three questionnaires were used to assess the patients' body image and level of perfectionism. The mean age was 33 years. The men numbered 32 and the women 48. The validated Spanish version of the Psychosocial Impact of Dental Aesthetic Questionnaire (PIDAQ) was used to assess the psychosocial impact of their dental esthetics. The Multidimensional Perfectionism Scale (MPS) was used to assess how perfectionist the patients were. A version of the Multidimensional Body-Self Relations Questionnaire (MBSRQ) was used for assessment of their body image. Student's t-test was used to compare the means and 95% confidence intervals (P < .05), and a logistic regression model was used for multivariate analysis. The PIDAQ (55.4 vs 60, P  =  .218) and MBSRQ (128.7 vs 125.9, P  =  .523) results of the patients who chose lingual orthodontics did not differ significantly from those who opted for labial orthodontics. However, the MPS scores of the lingual orthodontic patients were significantly higher (95.9 vs 86.3, P  =  .044), and high social class, over 30 years of age, and perfectionist traits were significant independent variables in this group. This pilot study may indicate that lingual orthodontic patients are more perfectionists than labial orthodontic patients.

  18. Peritumoral edema of meningiomas and metastatic brain tumors: differences in diffusion characteristics evaluated with diffusion-tensor MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Toh, Cheng-Hong; Wong, Alex M.-C; Wong, Ho-Fai; Wan, Yung-Liang [Chang Gung Memorial Hospital, Department of Medical Imaging and Intervention, Tao-Yuan (China); Chang Gung University, School of Medicine and Medical Technology, Tao-Yuan (China); Wei, Kuo-Chen [Chang Gung Memorial Hospital, Department of Neurosurgery, Tao-Yuan (China); Chang Gung University, School of Medicine and Medical Technology, Tao-Yuan (China); Ng, Shu-Hang [Chang Gung Memorial Hospital, Department of Medical Imaging and Intervention, Tao-Yuan (China); Chang Gung University, School of Medicine and Medical Technology, Tao-Yuan (China); Chang Gung Memorial Hospital, Molecular Image Center, Tao-Yuan (China)

    2007-06-15

    We prospectively compared the fractional anisotropy (FA) and mean diffusivity (MD) of the peritumoral edema of meningiomas and metastatic brain tumors with diffusion-tensor magnetic resonance (MR) imaging. The study protocol was approved by the local ethics committee, and written informed consent was obtained. Preoperative diffusion-tensor MR imaging was performed in 15 patients with meningiomas and 11 patients with metastatic brain tumors. Regions of interest (ROI) were placed in the peritumoral edema and normal-appearing white matter (NAWM) of the contralateral hemisphere to measure the FA and MD. The FA and MD ratios were calculated for each ROI in relation to the NAWM of the contralateral hemisphere. Changes in peritumoral MD and FA, in terms of primary values and ratios, were compared using a two-sample t-test; P < 0.05 was taken as indicating statistical significance. The mean MD values (x 10{sup -3} mm{sup 2}/s) of the peritumoral edema for metastases and meningiomas, respectively, were 0.902 {+-} 0.057 and 0.820 {+-} 0.094, the mean MD ratios were 220.3 {+-} 22.6 and 193.1 {+-} 23.4, the mean FA values were 0.146 {+-} 0.026 and 0.199 {+-} 0.052, and the mean FA ratios were 32.3 {+-} 5.9 and 46.0 {+-} 12.1. All the values were significantly different between metastases and meningiomas (MD values P = 0.016, MD ratios P = 0.006, FA values P = 0.005, FA ratios P = 0.002). The peritumoral edema of metastatic brain tumors and meningiomas show different MD and FA on diffusion-tensor MR imaging. (orig.)

  19. Comparative evaluation of image quality in computed radiology systems using imaging plates with different usage time; Avaliacao comparativa da qualidade da imagem em sistemas de radiologia computadorizada utilizando Imaging Plates com diferentes tempos de uso

    Energy Technology Data Exchange (ETDEWEB)

    Lazzaro, M.V.; Luz, R.M. da; Capaverde, A.S., E-mail: marcos.lazzaro@acad.pucrs.br [Hospital Sao Lucas (PUC-RS), Porto Alegre, RS (Brazil); Silva, A.M. Marques da [Pontificia Universidade Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Faculdade de Fisica

    2015-04-15

    Computed Radiology (CR) systems use imaging plates (IPs) for latent image acquisition. Taking into account the quality control (QC) of these systems, imaging plates usage time is undetermined. Different recommendations and publications on the subject suggest tests to evaluate these systems. The objective of this study is to compare the image quality of IPs of a CR system, in a mammography service, considering the usage time and consistency of assessments. 8 IPs were used divided into two groups: the first group included 4 IPs with 3 years of use (Group A); the second group consisted of 4 new IPs with no previous exposure (Group B). The tests used to assess the IP's quality were: Uniformity, Differential Signal to Noise Ratio (SDNR), Ghost Effect and Figure of Merit (FOM). Statistical results show that the proposed tests are shown efficient in assessing the conditions of image quality obtained in CR systems in mammography and can be used as determining factors for the replacement of IP's. Moreover, comparing the two sets of IP, results led to the replacement of all the set of IP’s with 3 years of use. This work demonstrates the importance of an efficient quality control, not only with regard to the quality of IP's used, but in the acquisition system as a whole. From this work, these tests will be conducted on an annual basis, already targeting as future work, monitoring the wear of IP's Group B and the creation of a baseline for analysis and future replacements. (author)

  20. Imaging of Flames in Cement Kilns To Study the Influence of Different Fuel Types

    DEFF Research Database (Denmark)

    Pedersen, Morten Nedergaard; Nielsen, Mads; Clausen, Sønnik

    2017-01-01

    in the three cement kilns and assess the effect of alternative fuels on the flame. It was found that cofiring with solid recovered fuel (SRF) would delay the ignition point by about 2 m and lower the intensity and temperature of the kiln flame compared to a fossil fuel flame. This is related to a larger...... particle size and moisture content of the alternative fuels, which lowers the conversion rate compared to fossil fuels. The consequences can be a lower kiln temperature and cement quality. The longer conversion time may also lead to the possibility of localized reducing conditions in the cement kiln, which......The cement industry aims to use an increased amount of alternative fuels to reduce production costs and CO2 emissions. In this study three cement plants firing different kinds and percentages of alternative fuel were studied. A specially developed camera setup was used to monitor the flames...

  1. Pinot Noir wine composition from different vine vigour zones classified by remote imaging technology.

    Science.gov (United States)

    Song, Jianqiang; Smart, Richard E; Dambergs, Robert G; Sparrow, Angela M; Wells, Reuben B; Wang, Hua; Qian, Michael C

    2014-06-15

    The relationship between grapevine vigour and grape and wine composition was investigated in this study. Own-rooted Pinot Noir grapevines were grown in a commercial vineyard in Tasmania, Australia, with uniform vineyard management practices. Vine vigours were determined by plant cell density (PCD) obtained from aerial photography. As vine vigour decreased, total soluble solid in grapes, total phenolics and anthocyanins in wines increased, while titratable acidity and yield decreased. Wines from the ultra low vine vigour zone had the highest concentrations of esters and alcohols. Higher level of linalool, nerol, geraniol, vitispirane, and β-ionone were observed in ultra low vigour and low vigour zones, but there was no obvious trend for citronellol and β-damascenone. Principal component analysis and discriminant analysis of the volatiles illustrated the differences among wines from the four vine vigour zones. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Differences in the known cellular composition of benign pigmented skin lesions reflected in computer-aided image analysis.

    Science.gov (United States)

    Choi, Jae Woo; Ryu, Hyeong Ho; Byun, Sang Young; Youn, Sang Woong

    2014-06-01

    Computer-aided image analysis (CAIA) has been suggested as an effective diagnostic tool for pigmented skin lesions (PSLs), especially melanoma. However, few studies on benign PSLs have been reported. The purpose of this study was to evaluate benign PSLs with our CAIA software and analyze the differences between the parameters of those lesions. By using homegrown CAIA software, we analyzed 3 kinds of PSLs-nevus, lentigo, and seborrheic keratosis. The group of seborrheic keratosis was divided into pigmented seborrheic keratosis, sebolentigine, and hyperkeratotic seborrheic keratosis. The CAIA was used to extract the color, as well as the morphological, textural, and topological features from each image. In line with clinical observations, the objective parameters indicated that nevus was dark and round, lentigo was small and bright, and seborrheic keratosis was large and spiky. The surface of nevus showed the highest contrast and correlation. In topological analysis, the concentricity clearly separated melanocytic lesions from seborrheic keratosis. The parameters of pigmented seborrheic keratosis were between those of typical nevus and seborrheic keratosis. We confirmed that definite correlations exist between the subjective differentiation by experts' examination and the objective evaluation by using CAIA. We also found that the morphological differences observed in CAIA were greatly influenced by the composition ratios of keratinocytes and melanocytes, which are already known histopathological characteristics of each PSL.

  3. Different strategies for reducing intestinal background radioactivity associated with imaging HSV1-tk expression using established radionucleoside probes

    Science.gov (United States)

    Ruggiero, Alessandro; Brader, Peter; Serganova, Inna; Zanzonico, Pat; Cai, Shangde; Lipman, Neil S.; Hricak, Hedvig; Blasberg, Ronald G.

    2011-01-01

    One limitation of HSV1-tk reporter PET imaging with nucleoside analogues is the high background radioactivity in the intestine. We hypothesized that endogenous expression of thymidine kinase in bacterial flora could phosphorylate and trap such radiotracers, contributing to the high radioactivity levels in the bowel and therefore explored different strategies to increase fecal elimination of radiotracer. Methods Intestinal radioactivity was assessed by in vivo microPET imaging and ex vivo tissue sampling following intravenous injection of 18F-FEAU, 124I-FIAU or 18F-FHBG in a germ-free mouse strain. We also explored the use of an osmotic laxative agent and/or a 100% enzymatically hydrolyzed liquid diet. Results No significant differences in intestinal radioactivity were observed between germ-free and normal mice. 18F-FHBG-derived intestinal radioactivity levels were higher than those of 18F-FEAU and 124I-FIAU; the intestine-to-blood ratio was more than 20-fold higher for 18F-FHBG than for 18F-FEAU and 124I-FIAU. The combination of Peptamen and Nulytely lowered intestinal radioactivity levels and increased (2.2-fold) the HSV1-tk transduced xenograft-to-intestine ratio for 18F-FEAU. Conclusions Intestinal bacteria in germ-free mice do not contribute to the high intestinal levels of radioactivity following injection of radionucleoside analogs. The combination of Peptamen and Nulytely increased radiotracer elimination by increasing bowel motility without inducing dehydration. PMID:20128998

  4. In vivo spectral imaging of different cell types in the small intestine by two-photon excited autofluorescence

    Science.gov (United States)

    Orzekowsky-Schroeder, Regina; Klinger, Antje; Martensen, Björn; Blessenohl, Maike; Gebert, Andreas; Vogel, Alfred; Hüttmann, Gereon

    2011-11-01

    Spectrally resolved two-photon excited autofluorescence imaging is used to distinguish different cell types and functional areas during dynamic processes in the living gut. Excitation and emission spectra of mucosal tissue and tissue components are correlated to spectra of endogenous chromophores. We show that selective excitation with only two different wavelengths within the tuning range of a Ti:sapphire femtosecond laser system yields excellent discrimination between enterocytes, antigen presenting cells and lysosomes based on the excitation and emission properties of their autofluorescence. The method is employed for time-lapse microscopy over up to 8 h. Changes of the spectral signature with the onset of photodamage are demonstrated, and their origin is discussed.

  5. Is magnetic resonance imaging of hepatic hemangioma any different in liver fibrosis and cirrhosis compared to normal liver?

    Energy Technology Data Exchange (ETDEWEB)

    Duran, Rafael, E-mail: rafael.duran@chuv.ch [Centre Hospitalier Universitaire Vaudois, University of Lausanne, Diagnostic and Interventional Radiology, Lausanne (Switzerland); Assistance-Publique Hôpitaux de Paris, APHP, Hôpital Beaujon, Department of Radiology, Clichy (France); Ronot, Maxime, E-mail: Maxime.ronot@bjn.aphp.fr [Assistance-Publique Hôpitaux de Paris, APHP, Hôpital Beaujon, Department of Radiology, Clichy (France); University Paris Diderot, Sorbonne Paris Cité, INSERM U773, Centre de Recherche Biomédicale Bichat-Beaujon, CRB3 Paris (France); Di Renzo, Sara, E-mail: Direnzo.sara@gmail.com [Assistance-Publique Hôpitaux de Paris, APHP, Hôpital Beaujon, Department of Radiology, Clichy (France); Gregoli, Bettina, E-mail: Bettinagregoli@yahoo.it [Assistance-Publique Hôpitaux de Paris, APHP, Hôpital Beaujon, Department of Radiology, Clichy (France); Van Beers, Bernard E., E-mail: Bernard.van-beers@bjn.aphp.fr [Assistance-Publique Hôpitaux de Paris, APHP, Hôpital Beaujon, Department of Radiology, Clichy (France); Vilgrain, Valérie, E-mail: Valerie.vilgrain@bjn.aphp.fr [Assistance-Publique Hôpitaux de Paris, APHP, Hôpital Beaujon, Department of Radiology, Clichy (France); University Paris Diderot, Sorbonne Paris Cité, INSERM U773, Centre de Recherche Biomédicale Bichat-Beaujon, CRB3 Paris (France)

    2015-05-15

    Highlights: • Hemangiomas were similar in patients with or without chronic liver disease on MRI. • Decrease in size & number of hemangiomas could start before the onset of cirrhosis. • T2 shine-through effect was less frequently observed in cirrhosis. - Abstract: Purpose: To compare qualitative and quantitative magnetic resonance (MR) imaging characteristics of hepatic hemangiomas in patients with normal, fibrotic and cirrhotic livers. Materials and methods: Retrospective, institutional review board approved study (waiver of informed consent). Eighty-nine consecutive patients with 231 hepatic hemangiomas who underwent liver MR imaging for lesion characterization were included. Lesions were classified into three groups according to the patients’ liver condition: no underlying liver disease (group 1), fibrosis (group 2) and cirrhosis (group 3). Qualitative and quantitative characteristics (number, size, signal intensities on T1-, T2-, and DW MR images, T2 shine-through effect, enhancement patterns (classical, rapidly filling, delayed filling), and ADC values) were compared. Results: There were 160 (69%), 45 (20%), and 26 (11%) hemangiomas in groups 1, 2 and 3, respectively. Lesions were larger in patients with normal liver (group 1 vs. groups 2 and 3; P = .009). No difference was found between the groups on T2-weighted images (fat-suppressed fast spin-echo (P = .82) and single-shot (P = .25)) and in enhancement patterns (P = .56). Mean ADC values of hemangiomas were similar between groups 1, 2 and 3 (2.11 ± .52 × 10{sup −3} mm{sup 2}/s, 2.1 ± .53 × 10{sup −3} mm{sup 2}/s and 2.14 ± .44 × 10{sup −3} mm{sup 2}/s, P = 87, respectively). T2 shine-through effect was less frequently observed in cirrhosis (P = .02). Conclusion: MR imaging characteristics of hepatic hemangioma were similar in patients with normal compared to fibrotic and cirrhotic livers. Smaller lesion size was observed with liver disease and less T2 shine-through effect was seen in

  6. Ocular Image and Haemodynamic Features Associated with Different Gradings of Ipsilateral Internal Carotid Artery Stenosis

    Directory of Open Access Journals (Sweden)

    Hui Wang

    2017-01-01

    Full Text Available Objectives. To analyse the changes of ocular haemodynamics and morphology in Chinese patients with internal carotid artery (ICA stenosis in the current study. Methods. A retrospective case-control study was conducted with 219 patients. The haemodynamic characteristics, the calibre of retinal vessels, and the subfoveal choroidal thickness (SFChT were compared. We analysed the correlations with the degree of ipsilateral ICA stenosis. Results. There were no significant differences among the groups in the central retinal artery equivalent (CRAE, central retinal vein equivalent (CRVE, and AVR (p=0.073, p=0.188, and p=0.738, resp.. The peak systolic velocity (PSV and end diastolic velocity (EDV in the central retinal artery (CRA and the posterior ciliary artery (PCA were significantly lower than normal eyes (p<0.001. The outer retinal layer thickness and SFChT values of the ICA stenosis groups were significantly lower than normal eyes (p=0.030 and p<0.001, resp.. Conclusion. The PSV and EDV in CRA and PCA and the SFChT and outer retinal layer thickness of ICA eyes were significantly lower than normal eyes. ICA stenosis may impact choroidal haemodynamics, and decreased choroidal circulation might affect the discordance of the SFChT and the outer retinal layer thickness.

  7. Different hydroxyapatite magnetic nanoparticles for medical imaging: Its effects on hemostatic, hemolytic activity and cellular cytotoxicity.

    Science.gov (United States)

    Laranjeira, Marta S; Moço, Ana; Ferreira, Jorge; Coimbra, Susana; Costa, Elísio; Santos-Silva, Alice; Ferreira, Paulo J; Monteiro, Fernando J

    2016-10-01

    Magnetic nanoparticles (MNPs) should be highly biocompatible, stable and safely eliminated from the body, and can therefore be successfully used in modern medicine. Synthetic hydroxyapatite (HAP) has well established biocompatible and non-inflammatory properties, as well as a highly stable and flexible structure that allows for an easy incorporation of magnetic ions. This study characterized and compared the in vitro cytotoxicity and hemocompatibility of hydroxyapatite MNPs doped with different ions (Gd(3+/)Fe(2+)/Fe(3+)/Co(2+)). HAP doped with 10% of Gd and Fe(III) presented the highest magnetic moments. Our results showed that Gd doped HAP nanoparticles are non-cytotoxic, hemocompatible, non-hemolytic and non-thrombogenic, in contrast with Fe(III) doped HAP that can be considered thrombogenic. For these reasons we propose that, Gd doped HAP nanoparticles have the most potential for application as a MRI contrast agents. However, use of Fe (III) doped HAP as MRI contrast agents should be further investigated. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Analysis of different image-based biofeedback models for improving cycling performances

    Science.gov (United States)

    Bibbo, D.; Conforto, S.; Bernabucci, I.; Carli, M.; Schmid, M.; D'Alessio, T.

    2012-03-01

    Sport practice can take advantage from the quantitative assessment of task execution, which is strictly connected to the implementation of optimized training procedures. To this aim, it is interesting to explore the effectiveness of biofeedback training techniques. This implies a complete chain for information extraction containing instrumented devices, processing algorithms and graphical user interfaces (GUIs) to extract valuable information (i.e. kinematics, dynamics, and electrophysiology) to be presented in real-time to the athlete. In cycling, performance indexes displayed in a simple and perceivable way can help the cyclist optimize the pedaling. To this purpose, in this study four different GUIs have been designed and used in order to understand if and how a graphical biofeedback can influence the cycling performance. In particular, information related to the mechanical efficiency of pedaling is represented in each of the designed interfaces and then displayed to the user. This index is real-time calculated on the basis of the force signals exerted on the pedals during cycling. Instrumented pedals for bikes, already designed and implemented in our laboratory, have been used to measure those force components. A group of subjects underwent an experimental protocol and pedaled with (the interfaces have been used in a randomized order) and without graphical biofeedback. Preliminary results show how the effective perception of the biofeedback influences the motor performance.

  9. Imaging of 3-D seismic velocity structure of Southern Sumatra region using double difference tomographic method

    Energy Technology Data Exchange (ETDEWEB)

    Lestari, Titik, E-mail: t2klestari@gmail.com [Meteorological Climatological and Geophysical Agency (MCGA), Jalan Angkasa I No.2 Kemayoran, Jakarta Pusat, 10720 (Indonesia); Faculty of Earth Science and Technology, Bandung Institute of Technology, Jalan Ganesa No.10, Bandung 40132 (Indonesia); Nugraha, Andri Dian, E-mail: nugraha@gf.itb.ac.id [Global Geophysical Research Group, Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology, Jalan Ganesa 10 Bandung 40132 (Indonesia)

    2015-04-24

    Southern Sumatra region has a high level of seismicity due to the influence of the subduction system, Sumatra fault, Mentawai fault and stretching zone activities. The seismic activities of Southern Sumatra region are recorded by Meteorological Climatological and Geophysical Agency (MCGA’s) Seismograph network. In this study, we used earthquake data catalog compiled by MCGA for 3013 events from 10 seismic stations around Southern Sumatra region for time periods of April 2009 – April 2014 in order to invert for the 3-D seismic velocities structure (Vp, Vs, and Vp/Vs ratio). We applied double-difference seismic tomography method (tomoDD) to determine Vp, Vs and Vp/Vs ratio with hypocenter adjustment. For the inversion procedure, we started from the initial 1-D seismic velocity model of AK135 and constant Vp/Vs of 1.73. The synthetic travel time from source to receiver was calculated using ray pseudo-bending technique, while the main tomographic inversion was applied using LSQR method. The resolution model was evaluated using checkerboard test and Derivative Weigh Sum (DWS). Our preliminary results show low Vp and Vs anomalies region along Bukit Barisan which is may be associated with weak zone of Sumatran fault and migration of partial melted material. Low velocity anomalies at 30-50 km depth in the fore arc region may indicated the hydrous material circulation because the slab dehydration. We detected low seismic seismicity in the fore arc region that may be indicated as seismic gap. It is coincides contact zone of high and low velocity anomalies. And two large earthquakes (Jambi and Mentawai) also occurred at the contact of contrast velocity.

  10. Loss of surface horizon of an irrigated soil detected by radiometric images of normalized difference vegetation index.

    Science.gov (United States)

    Fabian Sallesses, Leonardo; Aparicio, Virginia Carolina; Costa, Jose Luis

    2017-04-01

    The use of the soil in the Humid Pampa of Argentina has changed since the mid-1990s from agricultural-livestock production (that included pastures with direct grazing) to a purely agricultural production. Also, in recent years the area under irrigation by central pivot has been increased to 150%. The waters used for irrigation are sodium carbonates. The combination of irrigation and rain increases the sodium absorption ratio of soil (SARs), consequently raising the clay dispersion and reducing infiltration. This implies an increased risk of soil loss. A reduction in the development of white clover crop (Trifolium repens L.) was observed at an irrigation plot during 2015 campaign. The clover was planted in order to reduce the impact of two maize (Zea mays L.) campaigns under irrigation, which had increased soil SAR and deteriorated soil structure. SPOT-5 radiometric normalized difference vegetation index (NDVI) images were used to determine two zones of high and low production. In each zone, four random points were selected for further geo-referenced field sampling. Two geo-referenced measures of effective depth and surface soil sampling were carried out in each point. Texture of soil samples was determined by Pipette Method of Sedimentation Analysis. Data exploratory analysis showed that low production zone had a media effective depth = 80 cm and silty clay loam texture, while high production zone had a media effective depth > 140 cm and silt loam texture. The texture class of the low production zone did not correspond to prior soil studies carried out by the INTA (National Institute of Agricultural Technology), which showed that those soil textures were silt loam at surface and silty clay loam at sub-surface. The loss of the A horizon is proposed as a possible explanation, but further research is required. Besides, the need of a soil cartography actualization, which integrates new satellite imaging technologies and geo-referenced measurements with soil sensors is

  11. Reliability of different methodologies of infrared image analysis of myofascial trigger points in the upper trapezius muscle.

    Science.gov (United States)

    Dibai-Filho, Almir V; Guirro, Elaine C O; Ferreira, Vânia T K; Brandino, Hugo E; Vaz, Maíta M O L L; Guirro, Rinaldo R J

    2015-01-01

    Infrared thermography is recognized as a viable method for evaluation of subjects with myofascial pain. The aim of the present study was to assess the intra- and inter-rater reliability of infrared image analysis of myofascial trigger points in the upper trapezius muscle. A reliability study was conducted with 24 volunteers of both genders (23 females) between 18 and 30 years of age (22.12 ± 2.54), all having cervical pain and presence of active myofascial trigger point in the upper trapezius muscle. Two trained examiners performed analysis of point, line, and area of the infrared images at two different periods with a 1-week interval. The intra-class correlation coefficient (ICC(2,1)) was used to assess the intra- and inter-rater reliability. With regard to the intra-rater reliability, ICC values were between 0.591 and 0.993, with temperatures between 0.13 and 1.57 °C for values of standard error of measurement (SEM) and between 0.36 and 4.35 °C for the minimal detectable change (MDC). For the inter-rater reliability, ICC ranged from 0.615 to 0.918, with temperatures between 0.43 and 1.22 °C for the SEM and between 1.19 and 3.38 °C for the MDC. The methods of infrared image analyses of myofascial trigger points in the upper trapezius muscle employed in the present study are suitable for clinical and research practices.

  12. Identification of imaging biomarkers for the assessment of tumour response to different treatments in a preclinical glioma model

    Energy Technology Data Exchange (ETDEWEB)

    Lo Dico, A.; Martelli, C. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); University of Milan, Centre of Molecular and Cellular Imaging-IMAGO, Milan (Italy); Valtorta, S.; Belloli, S. [National Researches Council (CNR), Institute of Molecular Bioimaging and Physiology (IBFM), Segrate, MI (Italy); IRCCS San Raffaele Scientific Institute, Experimental Imaging Center, Milan (Italy); Raccagni, I.; Moresco, R.M. [IRCCS San Raffaele Scientific Institute, Experimental Imaging Center, Milan (Italy); University of Milano-Bicocca, Department of Health Sciences, Monza (Italy); Diceglie, C. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); University of Milan, Doctorate School of Molecular Medicine, Milan (Italy); Gianelli, U.; Bosari, S. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, Division of Pathology, Milan (Italy); Vaira, V. [Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, Division of Pathology, Milan (Italy); Istituto Nazionale Genetica Molecolare ' ' Romeo ed Enrica Invernizzi' ' (INGM), Milan (Italy); Politi, L.S. [IRCCS San Raffaele Scientific Institute, Neuroradiology Department and Neuroradiology Research Group, Milan (Italy); Lucignani, G. [University of Milan, Centre of Molecular and Cellular Imaging-IMAGO, Milan (Italy); University of Milan, Department of Health Sciences, Milan (Italy); San Paolo Hospital, Department of Diagnostic Services, Unit of Nuclear Medicine, Milan (Italy); Ottobrini, L. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); University of Milan, Centre of Molecular and Cellular Imaging-IMAGO, Milan (Italy); National Researches Council (CNR), Institute of Molecular Bioimaging and Physiology (IBFM), Segrate, MI (Italy)

    2015-03-27

    Hypoxia-inducible factor 1α (HIF-1α) activity is one of the major players in hypoxia-mediated glioma progression and resistance to therapies, and therefore the focus of this study was the evaluation of HIF-1α modulation in relation to tumour response with the purpose of identifying imaging biomarkers able to document tumour response to treatment in a murine glioma model. U251-HRE-mCherry cells expressing Luciferase under the control of a hypoxia responsive element (HRE) and mCherry under the control of a constitutive promoter were used to assess HIF-1α activity and cell survival after treatment, both in vitro and in vivo, by optical, MRI and positron emission tomography imaging. This cell model can be used to monitor HIF-1α activity after treatment with different drugs modulating transduction pathways involved in its regulation. After temozolomide (TMZ) treatment, HIF-1α activity is early reduced, preceding cell cytotoxicity. Optical imaging allowed monitoring of this process in vivo, and carbonic anhydrase IX (CAIX) expression was identified as a translatable non-invasive biomarker with potential clinical significance. A preliminary in vitro evaluation showed that reduction of HIF-1α activity after TMZ treatment was comparable to the effect of an Hsp90 inhibitor, opening the way for further elucidation of its mechanism of action. The results of this study suggest that the U251-HRE-mCherry cell model can be used for the monitoring of HIF-1α activity through luciferase and CAIX expression. These cells can become a useful tool for the assessment and improvement of new targeted tracers for potential theranostic procedures. (orig.)

  13. Comparison of Different Hypotheses Regarding the Spread of Alzheimer's Disease Using Markov Random Fields and Multimodal Imaging.

    Science.gov (United States)

    Dyrba, Martin; Grothe, Michel J; Mohammadi, Abdolreza; Binder, Harald; Kirste, Thomas; Teipel, Stefan J

    2017-07-01

    Alzheimer's disease (AD) is characterized by a cascade of pathological processes that can be assessed in vivo using different neuroimaging methods. Recent research suggests a systematic sequence of pathogenic events on a global biomarker level, but little is known about the associations and dependencies of distinct lesion patterns on a regional level. Markov random fields are a probabilistic graphical modeling approach that represent the interaction between individual random variables by an undirected graph. We propose the novel application of this approach to study the interregional associations and dependencies between multimodal imaging markers of AD pathology and to compare different hypotheses regarding the spread of the disease. We retrieved multimodal imaging data from 577 subjects enrolled in the Alzheimer's Disease Neuroimaging Initiative. Mean amyloid load (AV45-PET), glucose metabolism (FDG-PET), and gray matter volume (MRI) were calculated for the six principle nodes of the default mode network- a functional network of brain regions that appears to be preferentially targeted by AD. Multimodal Markov random field models were developed for three different hypotheses regarding the spread of the disease: the "intraregional evolution model", the "trans-neuronal spread" hypothesis, and the "wear-and-tear" hypothesis. The model likelihood to reflect the given data was evaluated using tenfold cross-validation with 1,000 repetitions. The most likely graph structure contained the posterior cingulate cortex as main hub region with edges to various other regions, in accordance with the "wear-and-tear" hypothesis of disease vulnerability. Probabilistic graphical models facilitate the analysis of interactions between several variables in a network model and therefore afford great potential to complement traditional multiple regression analyses in multimodal neuroimaging research.

  14. Use of different simulators to quality evaluation of image quality in digital mammography; Utilizacao de diferentes simuladores na avaliacao da qualidade da imagem em mamografia digital

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Leslie S.; Coutinho, Celia M.C., E-mail: leslie@ird.gov.br, E-mail: celia@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Magalhaes, Luis A.G.; Almeida, Carlos Eduardo de, E-mail: luisalexandregm@hotmail.com, E-mail: cea71@yahoo.com.br [Universidade do Estado do Rio de Janeiro (LCR/UERJ), Rio de Janeiro, RJ (Brazil). Laboratorio de Ciencias Radiologicas

    2013-11-01

    In this study, the digital images were acquired with different exposure simulators to evaluate the quality of the image, noting the tumor mass detection, microcalcification fiber and representing regions of interest during mammography. The technical parameters of exposure depends on the thickness and composition of the breast, thus affecting the dose and image quality. The simulators were used: ACR, SBP 1054, BREAST PHANTOM CIRS and for evaluation of image quality, as well as measures kerma incident on the entrance surface (Ki) and calculating the mean glandular dose (MGD)

  15. Different localization patterns of anthocyanin species in the pericarp of black rice revealed by imaging mass spectrometry.

    Directory of Open Access Journals (Sweden)

    Yukihiro Yoshimura

    Full Text Available Black rice (Oryza sativa L. Japonica contains high levels of anthocyanins in the pericarp and is considered an effective health-promoting food. Several studies have identified the molecular species of anthocyanins in black rice, but information about the localization of each anthocyanin species is limited because methodologies for investigating the localization such as determining specific antibodies to anthocyanin, have not yet been developed Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS is a suitable tool for investigating the localization of metabolites. In this study, we identified 7 species of anthocyanin monoglycosides and 2 species of anthocyanin diglycosides in crude extracts from black rice by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS analysis. We also analyzed black rice sections by MALDI-IMS and found 2 additional species of anthocyanin pentosides and revealed different localization patterns of anthocyanin species composed of different sugar moieties. Anthocyanin species composed of a pentose moiety (cyanidin-3-O-pentoside and petunidin-3-O-pentoside were localized in the entire pericarp, whereas anthocyanin species composed of a hexose moiety (cyanidin-3-O-hexoside and peonidin-3-O-hexoside were focally localized in the dorsal pericarp. These results indicate that anthocyanin species composed of different sugar moieties exhibit different localization patterns in the pericarp of black rice. This is the first detailed investigation into the localization of molecular species of anthocyanins by MALDI-IMS.

  16. Neuroanatomical patterns of cerebral white matter involvement in different motor neuron diseases as studied by diffusion tensor imaging analysis.

    Science.gov (United States)

    Müller, Hans-Peter; Unrath, Alexander; Huppertz, Hans-Jürgen; Ludolph, Albert C; Kassubek, Jan

    2012-05-01

    This study was designed to investigate differences of white matter (WM) involvement patterns in various motor neuron disorders (MND) by use of diffusion tensor imaging (DTI).DTI was acquired in ALS (n = 20), primary lateral sclerosis (n = 20), pure hereditary spastic paraparesis (HSP) (n = 20), and complicated HSP (n = 12). The data analysis was performed by voxelwise comparison of fractional anisotropy (FA) maps at group level together with fibre tracking in regions of interest (ROI) accompanied by tractwise fractional anisotropy statistics. DTI analysis revealed widespread patterns of alterations with a predominant deterioration of the motor system. These alterations encompassed, as the key structures, not only the corticospinal tracts (CST) but also distinct areas of the corpus callosum (CC), in particular its motor segment III. In conclusion, whole brain-based and tract-based DTI analysis was able to define a distinct WM pathoanatomy of different MND. These results may serve as an additional guidance in the identification of MRI-based parameters by showing a consistent CST and CC involvement, with differences in the extent of pathology, across a range of clinically different disorders. For potential future developments in MRI diagnostics in MND, a (perhaps multiparametric) ROI-based approach should include CST and the CC motor segment.

  17. SU-F-I-58: Image Quality Comparisons of Different Motion Magnitudes and TR Values in MR-PET

    Energy Technology Data Exchange (ETDEWEB)

    Patrick, J; Thompson, R [Lawson Health Research Institute, London, Ontario (Canada); Tavallaei, M; Drangova, M [Robarts Research Institute, London, Canada, London, Ontario (Canada); Stodilka, R [Western University, Canada, London, Ontario (Canada); Gaede, S [London Regional Cancer Program, London, Ontario (Canada)

    2016-06-15

    Purpose: The aim of this work is to evaluate the accuracy and sensitivity of a respiratory-triggered MR-PET protocol in detecting four different sized lesions at two different magnitudes of motion, with two different TR values, using a novel PET-MR-CT compatible respiratory motion phantom. Methods: The eight-compartment torso phantom was setup adjacent to the motion stage, which moved four spherical compartments (28, 22, 17, 10 mm diameter) in two separate (1 and 2 cm) linear motion profiles, simulating a 3.5 second respiratory cycle. Scans were acquired on a 3T MR-PET system (Biograph mMR; Siemens Medical Solutions, Germany). MR measurements were taken with: 1) Respiratory-triggered T2-weighted turbo spin echo (BLADE) sequence in coronal orientation, and 2) Real-time balanced steady-state gradient echo sequence (TrueFISP) in coronal and sagittal planes. PET was acquired simultaneously with MR. Sphere geometries and motion profiles were measured and compared with ground truths for T2 BLADE-TSE acquisitions and real time TrueFISP images. PET quantification and geometry measurements were taken using standardized uptake values, voxel intensity plots and were compared with known values, and examined alongside MR-based attenuation maps. Contrast and signal-to-noise ratios were also compared for each of the acquisitions as functions of motion range and TR. Results: Comparison of lesion diameters indicate the respiratory triggered T2 BLADE-TSE was able to maintain geometry within −2 mm for 1 cm motion for both TR values, and within −3.1 mm for TR = 2000 ms at 2 cm motion. Sphere measurements in respiratory triggered PET images were accurate within +/− 5 mm for both ranges of motion for 28, 22, and 17 mm diameter spheres. Conclusion: Hybrid MR-PET systems show promise in imaging lung cancer in non-compliant patients, with their ability to acquire both modalities simultaneously. However, MR-based attenuation maps are still susceptible to motion derived artifacts and

  18. Acoustic Imaging of Microstructure and Evaluation of the Adhesive's Physical, Mechanical and Chemical Properties Changes at Different Cure States

    Science.gov (United States)

    Severina, I. A.; Fabre, A. J.; Maeva, E. Yu.

    Epoxy thermoset adhesives transform during cure from liquid state into the highly cross-linked solid. Cure state of the material depends on condition of the reaction (temperature, pressure, time etc.) and resin/hardener ratio. It is known that the cure degree of the adhesive correlates with adhesion strength, which is critical for structural adhesives used in automotive, aerospace and marine industries. In this work, characterization of cure process of the adhesive with acoustic methods is presented. Evolution of the acoustic and elastic properties (attenuation, sound velocity, density, elastic moduli) during cure reaction was monitored in relation to the substantial physical and chemical changes of the material. These macro parameters of the adhesive were compared with the material's microstructure obtained by high-resolution acoustic microscopy technique in frequencies range of 50-400 MHz. Development of the microstructure of the adhesive as it cures at different conditions has been investigated. Appearance and development of the granular structure on the adhesive interface during cure reaction has been demonstrated. Acoustic images were analyzed by mathematical method to quantitatively characterize distribution of the adhesive's components. Statistical analysis of such images provides an accurate quantitative measure of the degree of cure of such samples. Research results presented in this paper can be useful as a basis for non-destructive evaluation of the adhesive materials

  19. Experimental validation of a finite-difference model for the prediction of transcranial ultrasound fields based on CT images

    Science.gov (United States)

    Bouchoux, Guillaume; Bader, Kenneth B.; Korfhagen, Joseph J.; Raymond, Jason L.; Shivashankar, Ravishankar; Abruzzo, Todd A.; Holland, Christy K.

    2012-12-01

    The prevalence of stroke worldwide and the paucity of effective therapies have triggered interest in the use of transcranial ultrasound as an adjuvant to thrombolytic therapy. Previous studies have shown that 120 kHz ultrasound enhanced thrombolysis and allowed efficient penetration through the temporal bone. The objective of our study was to develop an accurate finite-difference model of acoustic propagation through the skull based on computed tomography (CT) images. The computational approach, which neglected shear waves, was compared with a simple analytical model including shear waves. Acoustic pressure fields from a two-element annular array (120 and 60 kHz) were acquired in vitro in four human skulls. Simulations were performed using registered CT scans and a source term determined by acoustic holography. Mean errors below 14% were found between simulated pressure fields and corresponding measurements. Intracranial peak pressures were systematically underestimated and reflections from the contralateral bone were overestimated. Determination of the acoustic impedance of the bone from the CT images was the likely source of error. High correlation between predictions and measurements (R2 = 0.93 and R2 = 0.88 for transmitted and reflected waves amplitude, respectively) demonstrated that this model is suitable for a quantitative estimation of acoustic fields generated during 40-200 kHz ultrasound-enhanced ischemic stroke treatment.

  20. Amplification of enantiomeric excess, mirror-image symmetry breaking and kinetic proofreading in Soai reaction models with different oligomeric orders.

    Science.gov (United States)

    Micheau, Jean-Claude; Coudret, Christophe; Cruz, José-Manuel; Buhse, Thomas

    2012-10-14

    A comprehensive kinetic analysis of three prototypical autocatalytic cycle models based on the absolute asymmetric Soai reaction is presented. The three models, which can give rise to amplification of enantiomeric excess and mirror-image symmetry breaking, vary by their monomeric, dimeric or trimeric order of the assumed catalytic species. Our numerical approach considered the entire chiral combinatorics of the diastereomeric interactions in the models as well as the multiplicity of coupled reversible reactions without applying fast equilibration or quasi-steady state approximations. For the simplest monomeric model, an extensive range of parameters was explored employing a random grid parameter scanning method that revealed the influence of the parameter values on the product distribution, the reaction-time, the attenuation or amplification of enantiomeric excess as well as on the presence or absence of mirror-image symmetry breaking. A symmetry breaking test was imposed on the three models showing that an increase in the catalytic oligomer size from one to three leads to a higher tolerance to poorer chiral recognition between the diastereoisomers and identifies the greater impact of the diastereoisomeric energy difference over an imperfect stereoselectivity in the catalytic step. This robustness is understood as a particular case of so-called kinetic proofreading in asymmetric autocatalysis.

  1. Diagnosis of Mesiodistal Vertical Root Fractures in Teeth with Metal Posts: Influence of Applying Filters in Cone-beam Computed Tomography Images at Different Resolutions.

    Science.gov (United States)

    De Martin E Silva, Débora; Campos, Celso Neiva; Pires Carvalho, Antônio Carlos; Devito, Karina Lopes

    2017-11-16

    The aim of this article was to evaluate the influence of applying filters in cone-beam computed tomography (CBCT) images at different resolutions. These CBCT images were obtained for diagnosing mesiodistal vertical root fractures (VRFs) in teeth with metal posts. Forty teeth were treated endodontically, and 20 received metal posts. Ten teeth without posts and 10 teeth with posts were subjected to VRF in the mesiodistal direction. The sample was submitted to periapical radiographs and CBCT exams with a voxel of 0.25 and 0.30 mm. To reduce the influence of the metal artifact in the CT images, the teeth were evaluated with and without the application of filters ("Sharpen" and "Hard"). The images were evaluated by 2 radiologists who identified the presence of VRF. Accuracy values (receiver operating characteristic curves) for the different variables were compared by using analysis of variance and t test. No difference was observed between images with and without filter application (P > .05). Images obtained with a 0.25-mm voxel were more accurate (P images showed superior results compared with periapical radiographs (P images are superior to the periapical radiographs. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  2. Gender differences in the association among nicotine dependence, body image, depression, and anxiety within a college population.

    Science.gov (United States)

    Psujek, Jessica K; Martz, Denise M; Curtin, Lisa; Michael, Kurt D; Aeschleman, Stanley R

    2004-02-01

    Previous research has linked female weight concerns and smoking. This study examined whether poor body image and other eating disorder variables, after controlling for symptoms of anxiety and depression, were predictive of smoking severity in a sample of 478 college students (n=215 males, n=246 females). Contrary to our hypotheses and recent research, the predictors were not associated with nicotine dependence for females (R(2)=.00), and only dieting was negatively associated with nicotine dependence for males. These findings might be attributable to differences in how nicotine dependence is operationalized, the use of point prevalence symptom data versus lifetime prevalence of psychopathology, the severity of psychopathology in the present sample, or the use of a cross-sectional as opposed to a longitudinal design.

  3. Gender Related Differences in Response to “In Favor of Myself” Wellness Program to Enhance Positive Self & Body Image among Adolescents

    OpenAIRE

    Moria Golan; Noa Hagay; Snait Tamir

    2014-01-01

    BACKGROUND: Physical, neurological and psychological changes are often experienced differently by male and female adolescents. Positive self-esteem, emotional well-being, school achievements, and family connectedness are considered as protective factors against health-compromising behaviors. This study examines the gender differences in respect to the effect of a school-based interactive wellness program--"In Favor of Myself"--on self-image, body image, eating attitudes and behaviors of young...

  4. FDG PET imaging of Ela1-myc mice reveals major biological differences between pancreatic acinar and ductal tumours

    Energy Technology Data Exchange (ETDEWEB)

    Abasolo, Ibane [Institut Municipal d' Investigacio Medica-Hospital del Mar, Parc de Recerca Biomedica de Barcelona, Barcelona (Spain); Universitat Pompeu Fabra, Parc de Recerca Biomedica de Barcelona, Departament de Ciencies Experimentals i de la Salut, Barcelona (Spain); Institut d' Alta Tecnologia - CRC, Parc de Recerca Biomedica de Barcelona, Barcelona (Spain); Pujal, Judit; Navarro, Pilar [Institut Municipal d' Investigacio Medica-Hospital del Mar, Parc de Recerca Biomedica de Barcelona, Barcelona (Spain); Rabanal, Rosa M.; Serafin, Anna [Universitat Autonoma de Barcelona, Departament de Medicina i Cirurgia Animals, Barcelona (Spain); Millan, Olga [Institut d' Alta Tecnologia - CRC, Parc de Recerca Biomedica de Barcelona, Barcelona (Spain); Real, Francisco X. [Institut Municipal d' Investigacio Medica-Hospital del Mar, Parc de Recerca Biomedica de Barcelona, Barcelona (Spain); Universitat Pompeu Fabra, Parc de Recerca Biomedica de Barcelona, Departament de Ciencies Experimentals i de la Salut, Barcelona (Spain); Programa de Patologia Molecular, Centro Nacional de Investigaciones Oncologicas, Madrid (Spain)

    2009-07-15

    The aim was to evaluate FDG PET imaging in Ela1-myc mice, a pancreatic cancer model resulting in the development of tumours with either acinar or mixed acinar-ductal phenotype. Transversal and longitudinal FDG PET studies were conducted; selected tissue samples were subjected to autoradiography and ex vivo organ counting. Glucose transporter and hexokinase mRNA expression was analysed by quantitative reverse transcription polymerase chain reaction (RT-PCR); Glut2 expression was analysed by immunohistochemistry. Transversal studies showed that mixed acinar-ductal tumours could be identified by FDG PET several weeks before they could be detected by hand palpation. Longitudinal studies revealed that ductal - but not acinar - tumours could be detected by FDG PET. Autoradiographic analysis confirmed that tumour areas with ductal differentiation incorporated more FDG than areas displaying acinar differentiation. Ex vivo radioactivity measurements showed that tumours of solely acinar phenotype incorporated more FDG than pancreata of non-transgenic littermates despite the fact that they did not yield positive PET images. To gain insight into the biological basis of the differential FDG uptake, glucose transporter and hexokinase transcript expression was studied in microdissected tumour areas enriched for acinar or ductal cells and validated using cell-specific markers. Glut2 and hexokinase I and II mRNA levels were up to 20-fold higher in ductal than in acinar tumours. Besides, Glut2 protein overexpression was found in ductal neoplastic cells but not in the surrounding stroma. In Ela1-myc mice, ductal tumours incorporate significantly more FDG than acinar tumours. This difference likely results from differential expression of Glut2 and hexokinases. These findings reveal previously unreported biological differences between acinar and ductal pancreatic tumours. (orig.)

  5. A Method for Application of Classification Tree Models to Map Aquatic Vegetation Using Remotely Sensed Images from Different Sensors and Dates

    Directory of Open Access Journals (Sweden)

    Ying Cai

    2012-09-01

    Full Text Available In previous attempts to identify aquatic vegetation from remotely-sensed images using classification trees (CT, the images used to apply CT models to different times or locations necessarily originated from the same satellite sensor as that from which the original images used in model development came, greatly limiting the application of CT. We have developed an effective normalization method to improve the robustness of CT models when applied to images originating from different sensors and dates. A total of 965 ground-truth samples of aquatic vegetation types were obtained in 2009 and 2010 in Taihu Lake, China. Using relevant spectral indices (SI as classifiers, we manually developed a stable CT model structure and then applied a standard CT algorithm to obtain quantitative (optimal thresholds from 2009 ground-truth data and images from Landsat7-ETM+, HJ-1B-CCD, Landsat5-TM and ALOS-AVNIR-2 sensors. Optimal CT thresholds produced average classification accuracies of 78.1%, 84.7% and 74.0% for emergent vegetation, floating-leaf vegetation and submerged vegetation, respectively. However, the optimal CT thresholds for different sensor images differed from each other, with an average relative variation (RV of 6.40%. We developed and evaluated three new approaches to normalizing the images. The best-performing method (Method of 0.1% index scaling normalized the SI images using tailored percentages of extreme pixel values. Using the images normalized by Method of 0.1% index scaling, CT models for a particular sensor in which thresholds were replaced by those from the models developed for images originating from other sensors provided average classification accuracies of 76.0%, 82.8% and 68.9% for emergent vegetation, floating-leaf vegetation and submerged vegetation, respectively. Applying the CT models developed for normalized 2009 images to 2010 images resulted in high classification (78.0%–93.3% and overall (92.0%–93.1% accuracies. Our

  6. A Method for Application of Classification Tree Models to Map Aquatic Vegetation Using Remotely Sensed Images from Different Sensors and Dates

    Science.gov (United States)

    Jiang, Hao; Zhao, Dehua; Cai, Ying; An, Shuqing

    2012-01-01

    In previous attempts to identify aquatic vegetation from remotely-sensed images using classification trees (CT), the images used to apply CT models to different times or locations necessarily originated from the same satellite sensor as that from which the original images used in model development came, greatly limiting the application of CT. We have developed an effective normalization method to improve the robustness of CT models when applied to images originating from different sensors and dates. A total of 965 ground-truth samples of aquatic vegetation types were obtained in 2009 and 2010 in Taihu Lake, China. Using relevant spectral indices (SI) as classifiers, we manually developed a stable CT model structure and then applied a standard CT algorithm to obtain quantitative (optimal) thresholds from 2009 ground-truth data and images from Landsat7-ETM+, HJ-1B-CCD, Landsat5-TM and ALOS-AVNIR-2 sensors. Optimal CT thresholds produced average classification accuracies of 78.1%, 84.7% and 74.0% for emergent vegetation, floating-leaf vegetation and submerged vegetation, respectively. However, the optimal CT thresholds for different sensor images differed from each other, with an average relative variation (RV) of 6.40%. We developed and evaluated three new approaches to normalizing the images. The best-performing method (Method of 0.1% index scaling) normalized the SI images using tailored percentages of extreme pixel values. Using the images normalized by Method of 0.1% index scaling, CT models for a particular sensor in which thresholds were replaced by those from the models developed for images originating from other sensors provided average classification accuracies of 76.0%, 82.8% and 68.9% for emergent vegetation, floating-leaf vegetation and submerged vegetation, respectively. Applying the CT models developed for normalized 2009 images to 2010 images resulted in high classification (78.0%–93.3%) and overall (92.0%–93.1%) accuracies. Our results suggest

  7. SU-F-J-40: Evaluation of Sensitivity of the Automatic Matching Between Cone-Beam CT Image and Simulation CT Image in TrueBeam 2.0 Imaging System 6DoF Considering Different Uncertainty Sources

    Energy Technology Data Exchange (ETDEWEB)

    Bonaque, J; Bautista-Ballesteros, J; Ibanez-Rosello, B; Lliso, F; Carmona, V; Gimeno, J [Hospital La Fe, Valencia, Valencia (Spain); Perez-Calatayud, J [Hospital La Fe, Valencia, Valencia (Spain); Clinica Benidorm, Benidorm, Alicante (Spain)

    2016-06-15

    Purpose: To estimate the sensitivity of TrueBeam 2.0 Imaging System 6DoF automatic matching tool through the acquisition of cone-beam CT images in different phantoms applying submillimeter translations and rotations of tenths of a degree and registered with image simulation CT. Methods: To evaluate overall system-wide image, we consider two uncertainties source; First, the uncertainty of the manual phantom displacement (ε-m). This uncertainty is calculated by a digital caliper (0.01 mm) for vertical (Vrt), lateral (Lat) and longitudinal (Lng). A digital inclinometer (0.01°) for the pitch and roll and the own phantom scale to evaluate the coordinate rotation (Rtn). The second uncertainty is the displacement detected by the algorithm system of matching (σ-d) that we obtain from the standard deviations of the different measurements. We use three different phantoms. The BrainLab Radiosurgery system for supporting masks with an anthropomorphic dummy adapted to allow displacements of 0.1 mm in Vrt, Lat and Lng dimensions and rotations of 0.1° in Pitch dimension. For the analysis of the Rtn and Roll dimensions we use two homemade phantoms (RinoRot and RinoRoll, La Fe Hospital, Valencia, Spain) that allow rotations of 0.3°. Results: In the case of manual displacement of 0.10 ± 0.03 mm in the translations, the system detect 0.10 ± 0.07 mm, 0.12 ± 0.07 mm and 0.13 ± 0.07 mm (mean ± SD) in Lat, Vrt and Lng respectively. In the case of rotational dimension, manual displacement of 0.3 ± 0.1° was detected with 0.19 ± 0.06°, 0.29 ± 0.03° and 0.27 ± 0.06° in Pitch, Roll and Rtn. Conclusion: We conclude that the sensitivity of the automatic matching system is within 0.10 mm in translations and 0.3° in rotations. These values are under the own sensitivity of the software.

  8. Brain Differences in Infants at Differential Genetic Risk for Late-Onset Alzheimer Disease A Cross-sectional Imaging Study

    Science.gov (United States)

    Dean, Douglas C.; Jerskey, Beth A.; Chen, Kewei; Protas, Hillary; Thiyyagura, Pradeep; Roontiva, Auttawat; O’Muircheartaigh, Jonathan; Dirks, Holly; Waskiewicz, Nicole; Lehman, Katie; Siniard, Ashley L.; Turk, Mari N.; Hua, Xue; Madsen, Sarah K.; Thompson, Paul M.; Fleisher, Adam S.; Huentelman, Matthew J.; Deoni, Sean C. L.; Reiman, Eric M.

    2014-01-01

    IMPORTANCE Converging evidence suggests brain structure alterations may precede overt cognitive impairment in Alzheimer disease by several decades. Early detection of these alterations holds inherent value for the development and evaluation of preventive treatment therapies. OBJECTIVE To compare magnetic resonance imaging measurements of white matter myelin water fraction (MWF) and gray matter volume (GMV) in healthy infant carriers and noncarriers of the apolipoprotein E (APOE) ε4 allele, the major susceptibility gene for late-onset AD. DESIGN, SETTING, AND PARTICIPANTS Quiet magnetic resonance imaging was performed at an academic research imaging center on 162 healthy, typically developing 2- to 25-month-old infants with no family history of Alzheimer disease or other neurological or psychiatric disorders. Cross-sectional measurements were compared in the APOE ε4 carrier and noncarrier groups. White matter MWF was compared in one hundred sixty-two 2- to 25-month-old sleeping infants (60 ε4 carriers and 102 noncarriers). Gray matter volume was compared in a subset of fifty-nine 6- to 25-month-old infants (23 ε4 carriers and 36 noncarriers), who remained asleep during the scanning session. The carrier and noncarrier groups were matched for age, gestational duration, birth weight, sex ratio, maternal age, education, and socioeconomic status. MAIN OUTCOMES AND MEASURES Automated algorithms compared regional white matter MWF and GMV in the carrier and noncarrier groups and characterized their associations with age. RESULTS Infant ε4 carriers had lower MWF and GMV measurements than noncarriers in precuneus, posterior/middle cingulate, lateral temporal, and medial occipitotemporal regions, areas preferentially affected by AD, and greater MWF and GMV measurements in extensive frontal regions and measurements were also significant in the subset of 2- to 6-month-old infants (MWF differences, P < .05, after correction for multiple comparisons; GMV differences, P < .001

  9. Differences in integrity of white matter and changes with training in spelling impaired children: a diffusion tensor imaging study.

    Science.gov (United States)

    Gebauer, D; Fink, A; Filippini, N; Johansen-Berg, H; Reishofer, G; Koschutnig, K; Kargl, R; Purgstaller, C; Fazekas, F; Enzinger, C

    2012-07-01

    While the functional correlates of spelling impairment have been rarely investigated, to our knowledge no study exists regarding the structural characteristics of spelling impairment and potential changes with interventions. Using diffusion tensor imaging at 3.0 T, we here therefore sought to investigate (a) differences between children with poor spelling abilities (training group and waiting group) and controls, and (b) the effects of a morpheme-based spelling intervention in children with poor spelling abilities on DTI parameters. A baseline comparison of white matter indices revealed significant differences between controls and spelling-impaired children, mainly located in the right hemisphere (superior corona radiata (SCR), posterior limb of internal capsule, superior longitudinal fasciculus). After 5 weeks of training, spelling ability improved in the training group, along with increases in fractional anisotropy and decreases of radial diffusivity in the right hemisphere compared to controls. In addition, significantly higher decreases of mean diffusivity in the right SCR for the spelling-impaired training group compared to the waiting group were observed. Our results suggest that spelling impairment is associated with differences in white-matter integrity in the right hemisphere. We also provide first indications that white matter changes occur during successful training, but this needs to be more specifically addressed in future research.

  10. Memory for emotional images differs according to the presence of depressive symptoms in individuals at risk for dementia.

    Science.gov (United States)

    Callahan, Brandy L; Laforce, Robert; Dugas, Michel; Hudon, Carol

    2017-04-01

    Studies of amnestic mild cognitive impairment (aMCI) and late-life depression (LLD) have examined the similarities and differences between these syndromes, but few have investigated how the cognitive profile of comorbid aMCI and subclinical depressive symptoms (aMCI/D+) may compare to that of aMCI or LLD. Memory biases for certain types of emotional information may distinguish these groups. A total of 35 aMCI, 23 aMCI/D+, 13 LLD, and 17 elderly controls (CONT) rated the valence (positive, negative, or neutral) of 30 pictures from the International Affective Picture System. Mean percent positive, negative, and neutral images recalled was compared within groups immediately and 30 minutes later. Overall memory performance was comparable in aMCI and aMCI/D+, and both recalled fewer items than CONT and LLD. Group differences emerged when valence ratings were considered: at immediate and delayed recall, positive and negative pictures were generally better-remembered than neutral pictures by CONT, aMCI, and LLD, but valence was not associated with recall in aMCI/D+. Follow-up analyses suggested that the perceived intensity of stimuli may explain the emotional enhancement effect in CONT, aMCI, and LLD. Results support previous research suggesting that the neuropsychological profile of aMCI/D+ is different from that of aMCI and LLD. Although depressed and non-depressed individuals with aMCI recall comparable quantities of information, the quality of the recalled information differs significantly. On theoretical grounds, this suggests the existence of distinct neurobiological or neurofunctional manifestations in both groups. Practically, these differences may guide the development of personalized emotion-focused encoding strategies in cognitive training programs.

  11. Categorical and specificity differences between user-supplied tags and search query terms for images. An analysis of Flickr tags and Web image search queries

    National Research Council Canada - National Science Library

    Yoon, JungWon; Chung, Eun Kyung

    2009-01-01

    Introduction. The purpose of this study is to compare characteristics and features of user-supplied tags and search query terms for images on the Flickr Website in terms of categories of pictorial meanings...

  12. Functional luminal imaging probe geometric and histomorphologic analysis of abdominal wall wound induced by different trocars in pigs.

    Science.gov (United States)

    Zhao, Jingbo; Liao, Donghua; McMahon, Barry P; O'Donovan, Deidre; Schiretz, Rich; Heninrich, Russell; Gregersen, Hans

    2009-05-01

    This study aimed to investigate wound geometry and tissue damage caused by several different trocar types using a quantitative functional luminal imaging probe (FLIP) geometric profile and histomorphologic analysis. Four pigs were used in this study. After general anesthesia, six different trocars were randomly inserted at preselected locations in the porcine abdominal wall. The hydration status of the animals was monitored and maintained. A bag mounted on a FLIP was used to profile the geometry of the trocar holes during distension. After the FLIP study, the abdominal wall surrounding the trocar holes was harvested. The tissue was fixed in neutral 10% buffered formalin solution for more than 24 h. The samples contained control tissue (undamaged) and test tissue (damaged) through the entire rectangular tissue block. Approximately four to seven slides were cut parallel to the surface from each sample. Each slide was photographed, and the morphometry of the hole and damaged areas were measured and displayed three-dimensionally. The histologic sections were analyzed with regard to acute damage, bleeding, and acute inflammation of the skin, muscle, and fascia. The FLIP study demonstrated differences between the six trocars. These were mainly due to differences between the Versaport Plus V2 bladed trocar with the smooth cannula, the Applied Medical Separator nonbladed access system with threaded cannula, and the VersaStep Plus trocar. The morphometry data showed the smallest hole and damage areas for the Versaport Plus V2 bladed trocar with the smooth cannula. The damaged area divided by the trocar hole area was smallest for the VersaStep plus trocar and the Ethicon Endopath bladed trocar with a stability cannula (p < 0.05). The histologic analysis showed that the VersaStep Plus trocar and the Ethicon Endopath bladed trocar with a stability cannula gave the least bleeding and inflammation (p < 0.05). An agreement was found between the geometric data obtained by FLIP

  13. Comparison of different phosphorus-containing ligands complexing {sup 68}Ga for PET-imaging of bone metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Fellner, M.; Riss, P.; Loktionova, N.; Zhernosekov, K.; Roesch, F. [Univ. of Mainz, Inst. of Nuclear Chemistry, Mainz (Germany); Thews, O. [Univ. of Mainz, Inst. of Pathophysiology, Mainz (Germany); Geraldes, C.F.G.C. [Univ. of Coimbra, Faculty of Science and Technology, and Center of Neurosciences and Cell Biology, Dept. of Life Science, Coimbra (Portugal); Kovacs, Z. [Univ. of Texas Southwestern Medical Center, Advanced Imaging Research Center, Dallas, TX (United States); Lukes, I. [Charles Univ., Dept. of Inorganic Chemistry, Prague (Czech Republic)

    2011-07-01

    {sup 99m}Tc-phosphonate structures are well established tracers for bone tumour imaging. Our objective was to investigate different {sup 68}Ga-labelled phosphonate ligands concerning labelling kinetics, binding to hydroxyapatite and bone imaging using {mu}-PET. Seven macrocyclic phosphorus-containing ligands and EDTMP were labelled in nanomolar scale with n.c.a. {sup 68}Ga in Na-HEPES buffer at pH{proportional_to}4. Except for DOTP, all ligands were labelled with >92% yield. Binding of the {sup 68}Ga-ligand complexes on hydroxyapatite was analysed to evaluate the effect of the number of the phosphorus acid groups on adsorption parameters. Adsorption of {sup 68}Ga-EDTMP and 68Ga-DOTP was >83%. For the {sup 68}Ga-NOTA-phosphonates an increasing binding with increasing number of phosphonate groups was observed but was still lower than {sup 68}Ga-DOTP and {sup 68}Ga-EDTMP. {mu}-PET studies in vivo were performed with {sup 68}Ga-EDTMP and {sup 68}Ga-DOTP with Wistar rats. While {sup 68}Ga-EDTMP-PET showed uptake on bone structures, an excess amount of the ligand (>1.5 mg EDTMP/kg body weight) had to be used, otherwise the {sup 68}Ga{sup 3+} is released from the complex and forms gallium hydroxide or it is transchelated to {sup 68}Ga-transferrin. As a result, the main focus of further phosphonate structures has to be on complex formation in high radiochemical yields with macrocyclic ligands with phosphonate groups that are not required for complexing {sup 68}Ga. (orig.)

  14. Adaptive iterative dose reduction algorithm in CT: Effect on image quality compared with filtered back projection in body phantoms of different sizes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Milim; Lee, Jeong Min; Son, Hyo Shin; Han, Joon Koo; Choi, Byung Ihn [College of Medicine, Seoul National University, Seoul (Korea, Republic of); Yoon, Jeong Hee; Choi, Jin Woo [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of)

    2014-04-15

    To evaluate the impact of the adaptive iterative dose reduction (AIDR) three-dimensional (3D) algorithm in CT on noise reduction and the image quality compared to the filtered back projection (FBP) algorithm and to compare the effectiveness of AIDR 3D on noise reduction according to the body habitus using phantoms with different sizes. Three different-sized phantoms with diameters of 24 cm, 30 cm, and 40 cm were built up using the American College of Radiology CT accreditation phantom and layers of pork belly fat. Each phantom was scanned eight times using different mAs. Images were reconstructed using the FBP and three different strengths of the AIDR 3D. The image noise, the contrast-to-noise ratio (CNR) and the signal-to-noise ratio (SNR) of the phantom were assessed. Two radiologists assessed the image quality of the 4 image sets in consensus. The effectiveness of AIDR 3D on noise reduction compared with FBP were also compared according to the phantom sizes. Adaptive iterative dose reduction 3D significantly reduced the image noise compared with FBP and enhanced the SNR and CNR (p < 0.05) with improved image quality (p < 0.05). When a stronger reconstruction algorithm was used, greater increase of SNR and CNR as well as noise reduction was achieved (p < 0.05). The noise reduction effect of AIDR 3D was significantly greater in the 40-cm phantom than in the 24-cm or 30-cm phantoms (p < 0.05). The AIDR 3D algorithm is effective to reduce the image noise as well as to improve the image-quality parameters compared by FBP algorithm, and its effectiveness may increase as the phantom size increases.

  15. Individual differences in audio-vocal speech imitation aptitude in late bilinguals: functional neuro-imaging and brain morphology.

    Science.gov (United States)

    Reiterer, Susanne Maria; Hu, Xiaochen; Erb, Michael; Rota, Giuseppina; Nardo, Davide; Grodd, Wolfgang; Winkler, Susanne; Ackermann, Hermann

    2011-01-01

    An unanswered question in adult language learning or late bi and multilingualism is why individuals show marked differences in their ability to imitate foreign accents. While recent research acknowledges that more adults than previously assumed can still acquire a "native" foreign accent, very little is known about the neuro-cognitive correlates of this special ability. We investigated 140 German-speaking individuals displaying varying degrees of "mimicking" capacity, based on natural language text, sentence, and word imitations either in their second language English or in Hindi and Tamil, languages they had never been exposed to. The large subject pool was strictly controlled for previous language experience prior to magnetic resonance imaging. The late-onset (around 10 years) bilinguals showed significant individual differences as to how they employed their left-hemisphere speech areas: higher hemodynamic activation in a distinct fronto-parietal network accompanied low ability, while high ability paralleled enhanced gray matter volume in these areas concomitant with decreased hemodynamic responses. Finally and unexpectedly, males were found to be more talented foreign speech mimics.

  16. Impact of Different Analytic Approaches on the Analysis of the Breast Fibroglandular Tissue Using Diffusion Weighted Imaging.

    Science.gov (United States)

    Choi, Yoon Jung; Chen, Jeon-Hor; Yu, Hon J; Li, Yifan; Su, Min-Ying

    2017-01-01

    Purpose. This study investigated the impact of the different region of interest (ROI) approaches on measurement of apparent diffusion coefficient (ADC) values in the breast firbroglandular tissue (FT). Methods. Breast MR images of 38 women diagnosed with unilateral breast cancer were studied. Percent density (PD) and ADC were measured from the contralateral normal breast. Four different ROIs were used for ADC measurement. The measured PD and ADC were correlated. Results. Among the four ROIs, the manually placed small ROI on FT gave the highest mean ADC (ADC = 1839 ± 343 [×10(-6) mm(2)/s]), while measurement from the whole breast gave the lowest mean ADC (ADC = 933 ± 383 [×10(-6) mm(2)/s]). The ADC measured from the whole breast was highly correlated with PD with r = 0.95. In slice-to-slice comparison, the central slices with more FT had higher ADC values than the peripheral slices did, presumably due to less partial volume effect from fat. Conclusions. Our results indicated that the measured ADC heavily depends on the composition of breast tissue contained in the ROI used for the ADC measurements. Women with low breast density showing lower ADC values were most likely due to the partial volume effect of fatty tissues.

  17. Impact of Different Analytic Approaches on the Analysis of the Breast Fibroglandular Tissue Using Diffusion Weighted Imaging

    Directory of Open Access Journals (Sweden)

    Yoon Jung Choi

    2017-01-01

    Full Text Available Purpose. This study investigated the impact of the different region of interest (ROI approaches on measurement of apparent diffusion coefficient (ADC values in the breast firbroglandular tissue (FT. Methods. Breast MR images of 38 women diagnosed with unilateral breast cancer were studied. Percent density (PD and ADC were measured from the contralateral normal breast. Four different ROIs were used for ADC measurement. The measured PD and ADC were correlated. Results. Among the four ROIs, the manually placed small ROI on FT gave the highest mean ADC (ADC = 1839 ± 343 [×10−6 mm2/s], while measurement from the whole breast gave the lowest mean ADC (ADC = 933 ± 383 [×10−6 mm2/s]. The ADC measured from the whole breast was highly correlated with PD with r=0.95. In slice-to-slice comparison, the central slices with more FT had higher ADC values than the peripheral slices did, presumably due to less partial volume effect from fat. Conclusions. Our results indicated that the measured ADC heavily depends on the composition of breast tissue contained in the ROI used for the ADC measurements. Women with low breast density showing lower ADC values were most likely due to the partial volume effect of fatty tissues.

  18. Impact of normal sexual dimorphisms on sex differences in structural brain abnormalities in schizophrenia assessed by magnetic resonance imaging.

    Science.gov (United States)

    Goldstein, Jill M; Seidman, Larry J; O'Brien, Liam M; Horton, Nicholas J; Kennedy, David N; Makris, Nikos; Caviness, Verne S; Faraone, Stephen V; Tsuang, Ming T

    2002-02-01

    Previous studies suggest that the impact of early insults predisposing to schizophrenia may have differential consequences by sex. We hypothesized that brain regions found to be structurally different in normal men and women (sexual dimorphisms) and abnormal in schizophrenia would show significant sex differences in brain abnormalities, particularly in the cortex, in schizophrenia. Forty outpatients diagnosed as having schizophrenia by DSM-III-R were systematically sampled to be comparable within sex with 48 normal comparison subjects on the basis of age, ethnicity, parental socioeconomic status, and handedness. A comprehensive assessment of the entire brain was based on T1-weighted 3-dimensional images acquired from a 1.5-T magnet. Multivariate general linear models for correlated data were used to test for sex-specific effects regarding 22 hypothesized cortical, subcortical, and cerebrospinal fluid brain volumes, adjusted for age and total cerebrum size. Sex x group interactions were also tested on asymmetries of the planum temporale, Heschl's gyrus, and superior temporal gyrus, additionally controlled for handedness. Normal patterns of sexual dimorphisms were disrupted in schizophrenia. Sex-specific effects were primarily evident in the cortex, particularly in the frontomedial cortex, basal forebrain, cingulate and paracingulate gyri, posterior supramarginal gyrus, and planum temporale. Normal asymmetry of the planum was also disrupted differentially in men and women with schizophrenia. There were no significant differential sex effects in subcortical gray matter regions or cerebrospinal fluid. Factors that produce normal sexual dimorphisms may be associated with modulating insults producing schizophrenia, particularly in the cortex.

  19. Individual differences in speech imitation/pronunciation aptitude in late bilinguals: functional neuro-imaging and brain morphology

    Directory of Open Access Journals (Sweden)

    Susanne Maria Reiterer

    2011-10-01

    Full Text Available An unanswered question in adult language learning or late bi- and multilingualism is why individuals show marked differences in their ability to imitate foreign accents. While recent research acknowledges that more adults than previously assumed can still acquire a native foreign accent, very little is known about the neuro-cognitive correlates of this special ability. We investigated 140 German speaking individuals displaying varying degrees of mimicking capacity, based on natural language text, sentence and word imitations either in their second language English or in Hindi and Tamil, languages they had never been exposed to. The large subject pool was extensively controlled for previous language experience prior to magnetic resonance imaging (MRI. The late-onset (around 10 years bilinguals showed significant individual differences as to how they employed their left-hemisphere speech areas: higher hemodynamic activation in a distinct fronto-parietal network accompanied low ability, while high ability paralleled enhanced gray matter volume in these areas concomitant with decreased hemodynamic responses. Finally and unexpectedly, males were found to be more talented foreign speech mimics.

  20. POLARIMETRIC SIGNATURES IDENTIFICATION FOR DIFFERENT FEATURES IN RADARSAT-2 POLSAR IMAGE: A CASE STUDY OF HALAYIB AREA, EGYPT

    Directory of Open Access Journals (Sweden)

    A. H. Nasr

    2016-06-01

    Full Text Available In fully polarized SAR (PolSAR data the returned signal from a target contains all polarizations. More information about this target may be inferred with respect to single-polarization. Distinct polarization separates targets due to its different backscattering responses. A Radarsat-2 PolSAR image acquired on December 2013 of part of Halayib area (Egypt was used in this study. Polarimetric signatures for various features (Wadi deposits, Tonalite, Chlorite schist, and Radar penetrated areas were derived and identified. Their Co-polarized and Cross-polarized signatures were generated, based on the calculation of the backscattered power at various ellipticity and orientation angles. Graphical 3D-representation of these features was provided and more details of their physical information are depicted according to their different polarization bases. The results illustrate that polarimetric signatures, obtained due to factors like surface roughness, dielectric constant and feature orientation, can be an effective representation for analyzing various features. The shape of the signature is significant and can also indicate the scattering mechanisms dominating the features response.

  1. The applicability of using different energy levels in CT imaging for differentiation or identification of dental restorative materials.

    Science.gov (United States)

    Kutschy, Josef M; Ampanozi, Garyfalia; Berger, Nicole; Ruder, Thomas D; Thali, Michael J; Ebert, Lars C

    2014-12-01

    The goal of this study was to investigate whether different computed tomography (CT) energy levels could supply additional information for the differentiation of dental materials for forensic investigations. Nine different commonly used restorative dental materials were investigated in this study. A total of 75 human third molars were filled with the restorative dental materials and then scanned using the forensic reference phantom in singlesource mode. The mean Hounsfield unit values and standard deviations (SDs) of each material were calculated at 120, 80 and 140 kVp. Most of the dental materials could be differentiated at 120 kVp. We found that greater X-ray density of a material resulted in higher SDs and that the material volume could influence the measurements. Differentiation of dental materials in CT was possible in many cases using single-energy CT scans at 120 kVp. Because of the number of dental restorative materials available and scanner and scan parameter dependence, as well as the CT imaging artifacts, the identification (in contrast to differentiation) was problematic.

  2. Different factors associate with body image in adolescence than in emerging adulthood: A gender comparison in a follow-up study

    Directory of Open Access Journals (Sweden)

    Sunna Gestsdottir

    2017-11-01

    Full Text Available Background Body image dissatisfaction has been linked with a range of adverse psychosocial outcomes in both genders and has become an important public health issue. Across all ages, women have reported being more dissatisfied with their bodies than men. The aim of the current study was to examine if fitness and physical activity associate with body image satisfaction differently across gender and age, measured in the same participants. Participants and procedure Participants were measured initially at age 15 years (N = 385 and again at age 23 years (N = 201. Structural equation modelling was used to examine the association between body image satisfaction, fitness, and physical activity. Covariates included skinfold thickness, body mass index, socioeconomic status, anxiety, and depression. Results Fitness and physical activity declined during the study period, body mass index increased, but no changes were found in body image satisfaction, depression, anxiety, or skinfold thickness. For women at ages 15 and 23 years, self-reported fitness and depression were found to be related to body image satisfaction, including body mass index at the age of 23 years. For 15-year-old men, skinfold thickness and aerobic fitness related to body image satisfaction, whereas skinfold thickness, depression, body mass index, and self-reported fitness did so at age 23 years. Conclusions Results suggest that different approaches are needed across gender to improve body image in adolescence whereas more similar ones can be used in emerging adulthood.

  3. Categorical and Specificity Differences between User-Supplied Tags and Search Query Terms for Images. An Analysis of "Flickr" Tags and Web Image Search Queries

    Science.gov (United States)

    Chung, EunKyung; Yoon, JungWon

    2009-01-01

    Introduction: The purpose of this study is to compare characteristics and features of user supplied tags and search query terms for images on the "Flickr" Website in terms of categories of pictorial meanings and level of term specificity. Method: This study focuses on comparisons between tags and search queries using Shatford's categorization…

  4. A High Speed CMOS Image Sensor with a Novel Digital Correlated Double Sampling and a Differential Difference Amplifier

    Directory of Open Access Journals (Sweden)

    Daehyeok Kim

    2015-03-01

    Full Text Available In order to increase the operating speed of a CMOS image sensor (CIS, a new technique of digital correlated double sampling (CDS is described. In general, the fixed pattern noise (FPN of a CIS has been reduced with the subtraction algorithm between the reset signal and pixel signal. This is because a single-slope analog-to-digital converter (ADC has been normally adopted in the conventional digital CDS with the reset ramp and signal ramp. Thus, the operating speed of a digital CDS is much slower than that of an analog CDS. In order to improve the operating speed, we propose a novel digital CDS based on a differential difference amplifier (DDA that compares the reset signal and the pixel signal using only one ramp. The prototype CIS has been fabricated with 0.13 µm CIS technology and it has the VGA resolution of 640 × 480. The measured conversion time is 16 µs, and a high frame rate of 131 fps is achieved at the VGA resolution.

  5. Structural differences in basal ganglia of elite running versus martial arts athletes: a diffusion tensor imaging study.

    Science.gov (United States)

    Chang, Yu-Kai; Tsai, Jack Han-Chao; Wang, Chun-Chih; Chang, Erik Chihhung

    2015-07-01

    The aim of this study was to use diffusion tensor imaging (DTI) to characterize and compare microscopic differences in white matter integrity in the basal ganglia between elite professional athletes specializing in running and martial arts. Thirty-three young adults with sport-related skills as elite professional runners (n = 11) or elite professional martial artists (n = 11) were recruited and compared with non-athletic and healthy controls (n = 11). All participants underwent health- and skill-related physical fitness assessments. Fractional anisotropy (FA) and mean diffusivity (MD), the primary indices derived from DTI, were computed for five regions of interest in the bilateral basal ganglia, including the caudate nucleus, putamen, globus pallidus internal segment (GPi), globus pallidus external segment (GPe), and subthalamic nucleus. Results revealed that both athletic groups demonstrated better physical fitness indices compared with their control counterparts, with the running group exhibiting the highest cardiovascular fitness and the martial arts group exhibiting the highest muscular endurance and flexibility. With respect to the basal ganglia, both athletic groups showed significantly lower FA and marginally higher MD values in the GPi compared with the healthy control group. These findings suggest that professional sport or motor skill training is associated with changes in white matter integrity in specific regions of the basal ganglia, although these positive changes did not appear to depend on the type of sport-related motor skill being practiced.

  6. Quantitative analysis of diffusion-weighted magnetic resonance imaging in malignant breast lesions using different b value combinations

    Energy Technology Data Exchange (ETDEWEB)

    Nilsen, Line B. [Oslo University Hospital, Department of Radiation Biology, Norwegian Radium Hospital, P.O. Box 4959, Oslo (Norway); University of Oslo, Faculty of Medicine, P.O. Box 1078, Oslo (Norway); Fangberget, Anne [Oslo University Hospital, Department of Radiology and Nuclear Medicine, Division of Diagnostics and Intervention, Norwegian Radium Hospital, P.O. Box 4959, Oslo (Norway); Geier, Oliver [Oslo University Hospital, Department of Diagnostic Physics, The Interventional Centre, Division of Diagnostics and Intervention, P.O. Box 4950, Oslo (Norway); Seierstad, Therese [Oslo University Hospital, Department of Radiology and Nuclear Medicine, Division of Diagnostics and Intervention, Norwegian Radium Hospital, P.O. Box 4959, Oslo (Norway); Buskerud University College, Department of Health Sciences, P.O. Box 7053, Drammen (Norway)

    2013-04-15

    To explore how apparent diffusion coefficients (ADCs) in malignant breast lesions are affected by selection of b values in the monoexponential model and to compare ADCs with diffusion coefficients (Ds) obtained from the biexponential model. Twenty-four women (mean age 51.3 years) with locally advanced breast cancer were included in this study. Pre-treatment diffusion-weighted magnetic resonance imaging was performed using a 1.5-T system with b values of 0, 50, 100, 250 and 800 s/mm{sup 2}. Thirteen different b value combinations were used to derive individual monoexponential ADC maps. All b values were used in the biexponential model. Median ADC (including all b values) and D were 1.04 x 10{sup -3} mm{sup 2}/s (range 0.82-1.61 x 10{sup -3} mm{sup 2}/s) and 0.84 x 10{sup -3} mm{sup 2}/s (range 0.17-1.56 x 10{sup -3} mm{sup 2}/s), respectively. There was a strong positive correlation between ADCs and Ds. For clinically relevant b value combinations, maximum deviation between ADCs including and excluding low b values (<100 s/mm{sup 2}) was 11.8 %. Selection of b values strongly affects ADCs of malignant breast lesions. However, by excluding low b values, ADCs approach biexponential Ds, demonstrating that microperfusion influences the diffusion signal. Thus, care should be taken when ADC calculation includes low b values. (orig.)

  7. Optimising Phenological Metrics Extraction for Different Crop Types in Germany Using the Moderate Resolution Imaging Spectrometer (MODIS

    Directory of Open Access Journals (Sweden)

    Xingmei Xu

    2017-03-01

    Full Text Available Phenological metrics extracted from satellite data (phenometrics have been increasingly used to access timely, spatially explicit information on crop phenology, but have rarely been calibrated and validated with field observations. In this study, we developed a calibration procedure to make phenometrics more comparable to ground-based phenological stages by optimising the settings of Best Index Slope Extraction (BISE and smoothing algorithms together with thresholds. We used a six-year daily Moderate Resolution Imaging Spectrometer (MODIS Normalized Difference Vegetation Index (NDVI time series and 211 ground-observation records from four major crop species (winter wheat/barley, oilseed rape, and sugar beet in central Germany. Results showed the superiority of the Savitzky–Golay algorithm in combination with BISE. The satellite-derived senescence dates matched ripeness stages of winter crops and the dates with maximum NDVI were closely related to the field-observed heading stage of winter cereals. We showed that the emergence of winter crops corresponded to the dates extracted with a threshold of 0.1, which translated into 8.89 days of root-mean-square error (RMSE improvement compared to the standard threshold of 0.5. The method with optimised settings and thresholds can be easily transferred and applied to areas with similar growing conditions. Altogether, the results improve our understanding of how satellite-derived phenometrics can explain in situ phenological observations.

  8. Developmental Stages and Sex Differences of White Matter and Behavioral Development through Adolescence: A Longitudinal Diffusion Tensor Imaging (DTI) Study

    Science.gov (United States)

    Simmonds, Daniel; Hallquist, Michael N.; Asato, Miya; Luna, Beatriz

    2014-01-01

    White matter (WM) continues to mature through adolescence in parallel with gains in cognitive ability. To date, developmental changes in human WM microstructure have been inferred using analyses of cross-sectional or two time-point follow-up studies, limiting our understanding of individual developmental trajectories. The aims of the present longitudinal study were to characterize the timing of WM growth and investigate how sex and behavior are associated with different developmental trajectories. We utilized diffusion tensor imaging (DTI) in 128 individuals ages 8-28, who received annual scans for up to 5 years and completed motor and cognitive tasks. Flexible nonlinear growth curves indicated a hierarchical pattern of WM development. By late childhood, posterior cortical-subcortical connections were similar to adults. During adolescence, WM microstructure reached adult levels, including frontocortical, frontosubcortical and cerebellar connections. Later to mature in adulthood were major corticolimbic association tracts and connections at terminal gray matter sites in cortical and basal ganglia regions. These patterns may reflect adolescent maturation of frontal connectivity supporting cognitive abilities, particularly the protracted refinement of corticolimbic connectivity underlying cognition-emotion interactions. Sex and behavior also played a large role. Males showed continuous WM growth from childhood through early adulthood, whereas females mainly showed growth during mid-adolescence. Further, earlier WM growth in adolescence was associated with faster and more efficient responding and better inhibitory control whereas later growth in adulthood was associated with poorer performance, suggesting that the timing of WM growth is important for cognitive development. PMID:24384150

  9. Learner Differences and Learning Outcomes in an Introductory Biochemistry Class: Attitude toward Images, Visual Cognitive Skills, and Learning Approach

    Science.gov (United States)

    Milner, Rachel E.

    2014-01-01

    The practice of using images in teaching is widespread, and in science education images are used so extensively that some have argued they are now the "main vehicle of communication" (C. Ferreira, A. Arroio "Problems Educ. 21st Century" 2009, 16, 48-53). Although this phenomenon is especially notable in the field of…

  10. Live cell imaging reveals different modes of cytotoxic action of extracts derived from commonly used luting cements.

    Science.gov (United States)

    Trumpaitė-Vanagienė, Rita; Čebatariūnienė, Alina; Tunaitis, Virginijus; Pūrienė, Alina; Pivoriūnas, Augustas

    2018-02-01

    To compare cytotoxicity of extracts derived from commonly used luting cements: Hoffmann's Zinc Phosphate (ZPC), GC Fuji Plus Resin Modified Glass Ionomer (RMGIC) and 3M ESPE RelyX Unicem Resin Cement (RC) on primary human gingival fibroblasts (HGFs). HGFs were exposed to different concentrations of the ZPC, RMGIC and RC extracts. The cytotoxicity was assessed with the PrestoBlue Cell Viability Reagent and viable cells were counted by a haemocytometer using the trypan blue exclusion test. In order to determine the primary mechanism of the cell death induced by extracts from different luting cements, the real-time monitoring of caspase-3/-7 activity and membrane integrity of cells was employed. The extracts from the RMGIC and ZPC decreased the metabolic activity and numbers of viable cells. Unexpectedly, the extracts from the RC evoked only small effects on the metabolic activity of HGFs with a decreasing number of viable cells in a dose-and time-dependent manner. The live cell imaging revealed that the apoptosis was the primary mechanism of a cell death induced by the extracts derived from the RMGIC, whereas the extracts from the RC and ZPC induced a cell death through a necrotic and caspase-independent pathway. The apoptosis was the primary mechanism of the cell death induced by the extracts derived from the RMGIC, whereas the extracts from the RC and ZPC induced a cell death via a necrotic pathway. We suggest that metabolic assays commonly used to assess the cytotoxicity of luting cements should be validated by alternative methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Differences between proximal versus distal intraorbital optic nerve diffusion tensor magnetic resonance imaging properties in glaucoma patients.

    Science.gov (United States)

    Bolacchi, Francesca; Garaci, Francesco Giuseppe; Martucci, Alessio; Meschini, Alessandro; Fornari, Maria; Marziali, Simone; Mancino, Raffaele; Squillaci, Ettore; Floris, Roberto; Cerulli, Luciano; Simonetti, Giovanni; Nucci, Carlo

    2012-06-28

    To analyze in vivo the diffusion tensor magnetic resonance imaging (DT-MRI) properties of the intraorbital optic nerve at two different levels: Proximal to the optic nerve head (ONH) and distal to the ONH at the level of the orbital apex in glaucoma patients. Twenty-four patients with primary open-angle glaucoma were examined. The categorization into early and severe glaucoma was performed by Hodapp's classification. Fifteen healthy individuals served as controls. DT-MRI was performed with a 3T-MR unit. At early stage mean diffusivity (MD) values were higher at the proximal site with respect to the distal site. On the contrary, a decrease in fractional anisotropy (FA) was observed only relative to patient stage, independent of optic nerve site. Moreover, at early disease stage an increase in overall diffusivities, was evident at the proximal site, whereas at the distal site a decrease of the largest diffusivity and an increase in both the intermediate and smallest diffusivities were observed. FA and MD measured at the proximal site, had, respectively, the highest sensitivity and specificity in discriminating between healthy and glaucomatous eyes. Our study represents the first attempt to evaluate in vivo fiber integrity changes along the optic nerve with DT-MRI. Optic nerve degeneration appears to be a process that affects differently the proximal and the distal segments of the optic nerve. The complementary high sensitivity of FA with the high specificity of MD at the proximal site may provide reliable indexes for the identification of glaucomatous patients at early stages.

  12. Biological tumour volumes of gliomas in early and standard 20-40 min18F-FET PET images differ according to IDH mutation status.

    Science.gov (United States)

    Unterrrainer, M; Winkelmann, I; Suchorska, B; Giese, A; Wenter, V; Kreth, F W; Herms, J; Bartenstein, P; Tonn, J C; Albert, N L

    2018-02-27

    For the clinical evaluation of O-(2- 18 F-fluoroethyl)-L-tyrosine ( 18 F-FET) PET images, the use of standard summation images obtained 20-40 min after injection is recommended. However, early summation images obtained 5-15 min after injection have been reported to allow better differentiation between low-grade glioma (LGG) and high-grade glioma (HGG) by capturing the early 18 F-FET uptake peak specific for HGG. We compared early and standard summation images with regard to delineation of the PET-derived biological tumour volume (BTV) in correlation with the molecular genetic profile according the updated 2016 WHO classification. The analysis included 245 patients with newly diagnosed, histologically verified glioma and a positive 18 F-FET PET scan prior to any further treatment. BTVs were delineated during the early 5-15 min and standard 20-40 min time frames using a threshold of 1.6 × background activity and were compared intraindividually. Volume differences between early and late summation images of >20% were considered significant and were correlated with WHO grade and the molecular genetic profile (IDH mutation and 1p/19q codeletion status). In 52.2% of the patients (128/245), a significant difference in BTV of >20% between early and standard summation images was found. While 44.3% of WHO grade II gliomas (31 of 70) showed a significantly smaller BTV in the early summation images, 35.0% of WHO grade III gliomas (28/80) and 37.9% of WHO grade IV gliomas (36/95) had a significantly larger BTVs. Among IDH-wildtype gliomas, an even higher portion (44.4%, 67/151) showed significantly larger BTVs in the early summation images, which was observed in 5.3% (5/94) of IDH-mutant gliomas only: most of the latter had significantly smaller BTVs in the early summation images, i.e. 51.2% of IDH-mutant gliomas without 1p/19q codeletion (21/41) and 39.6% with 1p/19q codeletion (21/53). BTVs delineated in early and standard summation images differed significantly in

  13. Magnetic Resonance Imaging of Cerebral Malaria Patients Reveals Distinct Pathogenetic Processes in Different Parts of the Brain.

    Science.gov (United States)

    Mohanty, Sanjib; Benjamin, Laura A; Majhi, Megharay; Panda, Premanand; Kampondeni, Sam; Sahu, Praveen K; Mohanty, Akshaya; Mahanta, Kishore C; Pattnaik, Rajyabardhan; Mohanty, Rashmi R; Joshi, Sonia; Mohanty, Anita; Turnbull, Ian W; Dondorp, Arjen M; Taylor, Terrie E; Wassmer, Samuel C

    2017-01-01

    The mechanisms underlying the rapidly reversible brain swelling described in patients with cerebral malaria (CM) are unknown. Using a 1.5-Tesla (T) magnetic resonance imaging (MRI) scanner, we undertook an observational study in Rourkela, India, of 11 Indian patients hospitalized with CM and increased brain volume. Among the 11 cases, there were 5 adults and 6 children. All patients had reduced consciousness and various degrees of cortical swelling at baseline. The latter was predominately posterior in distribution. The findings on diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps were consistent with vasogenic edema in all cases. Reversibility after 48 to 72 h was observed in >90% of cases. DWI/ADC mismatch suggested the additional presence of cytotoxic edema in the basal nuclei of 5 patients; all of these had perfusion parameters consistent with vascular engorgement and not with ischemic infarcts. Our results suggest that an impairment of the blood-brain barrier is responsible for the brain swelling in CM. In 5 cases, vasogenic edema occurred in conjunction with changes in the basal nuclei consistent with venous congestion, likely to be caused by the sequestration of Plasmodium falciparum-infected erythrocytes. While both mechanisms have been individually postulated to play an important role in the development of CM, this is the first demonstration of their concurrent involvement in different parts of the brain. The clinical and radiological characteristics observed in the majority of our patients are consistent with posterior reversible encephalopathy syndrome (PRES), and we show for the first time a high frequency of PRES in the context of CM. IMPORTANCE The pathophysiology and molecular mechanisms underlying cerebral malaria (CM) are still poorly understood. Recent neuroimaging studies demonstrated that brain swelling is a common feature in CM and a major contributor to death in pediatric patients. Consequently, determining the

  14. Gender Related Differences in Response to “In Favor of Myself” Wellness Program to Enhance Positive Self & Body Image among Adolescents

    Science.gov (United States)

    Golan, Moria; Hagay, Noa; Tamir, Snait

    2014-01-01

    Background Physical, neurological and psychological changes are often experienced differently by male and female adolescents. Positive self-esteem, emotional well-being, school achievements, and family connectedness are considered as protective factors against health-compromising behaviors. This study examines the gender differences in respect to the effect of a school-based interactive wellness program – “In Favor of Myself” – on self-image, body image, eating attitudes and behaviors of young adolescents. Methods Two hundred and ten adolescents (mean age 13.5) participated in the intervention group, 55% were girls and 45% boys. Program consisted of eight 90-minutes structured sessions integrated into a regular school coping skills curriculum. The program focused on self-esteem, self-image, body image, media literacy and cognitive dissonance. The overall impact of the program and the study protocol were previously published. Results Overall, there are gender related differences in respect to body image and self-image in young adolescents in response to “In Favor of Myself”. Compared to boys, girls reported at baseline higher self-esteem, being more contingent by appearance, and their self-image was more influenced by popularity, appearance, interpersonal communication and admired people. Furthermore girls presented greater gap between current body figure and perceived ideal figure. Not only were girls more dissatisfied with their body, but they were more active in attempts to become and/or remain “thin”. At program termination, gender × time effect was detected in reduction of self-worth contingent by others, change in importance given to achievements at schools, parents' perceptions, as well as the impact of comparisons to friends and family members on self-image. Conclusions Girls exhibited more gains than boys from ‘In Favor of Myself’ which raise the questions about how effective would be the program when delivered in mixed gender groups vs

  15. Online 3D terrain visualisation using Unity 3D game engine: A comparison of different contour intervals terrain data draped with UAV images

    Science.gov (United States)

    Hafiz Mahayudin, Mohd; Che Mat, Ruzinoor

    2016-06-01

    The main objective of this paper is to discuss on the effectiveness of visualising terrain draped with Unmanned Aerial Vehicle (UAV) images generated from different contour intervals using Unity 3D game engine in online environment. The study area that was tested in this project was oil palm plantation at Sintok, Kedah. The contour data used for this study are divided into three different intervals which are 1m, 3m and 5m. ArcGIS software were used to clip the contour data and also UAV images data to be similar size for the overlaying process. The Unity 3D game engine was used as the main platform for developing the system due to its capabilities which can be launch in different platform. The clipped contour data and UAV images data were process and exported into the web format using Unity 3D. Then process continue by publishing it into the web server for comparing the effectiveness of different 3D terrain data (contour data) draped with UAV images. The effectiveness is compared based on the data size, loading time (office and out-of-office hours), response time, visualisation quality, and frame per second (fps). The results were suggest which contour interval is better for developing an effective online 3D terrain visualisation draped with UAV images using Unity 3D game engine. It therefore benefits decision maker and planner related to this field decide on which contour is applicable for their task.

  16. Body Image Avoidance, Body Dissatisfaction, and Eating Pathology: Is There a Difference Between Male Gym Users and Non-Gym Users?

    Science.gov (United States)

    Stapleton, Peta; McIntyre, Timothy; Bannatyne, Amy

    2016-03-01

    With research highlighting the increasing prevalence and severity of body image and eating disturbances in males, particularly athletes and regular gymnasium users, the current study examined body image and eating disturbances in a sample of male gym users and non-gym users (N = 180). Based on previous research, it was predicted that male gym users would report greater body image disturbance (e.g., body image avoidance and body dissatisfaction) and eating pathology, compared with non-gym users. Results of the study partially supported hypotheses, revealing body dissatisfaction and eating pathology were significantly increased in male gym users. However, no significant differences were observed in body image avoidance behaviors, though this is likely because of methodological limitations associated with psychometric measures selected. The study provides preliminary evidence that male gym users do experience subclinical eating and body image concerns, with some also experiencing clinically significant symptoms that could be precursors to the later development of an eating disorder. Results of the current study highlight the importance of educating key stakeholders within health and fitness centers, through community-based interventions, to increase awareness regarding male body image and eating disturbances. © The Author(s) 2014.

  17. Differences in the origins of kinetochore-positive and kinetochore-negative micronuclei: A live cell imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Erkang, E-mail: erkangj@ustc.edu.cn

    2016-05-15

    Highlights: • Most Kinetochore-negative micronuclei were derived from kinetochore-negative displaced chromosomes, kinetochore-negative lagging chromosomes and fragments of broken chromosome bridges in mitosis of MN-free cells. • Most Kinetochore-positive micronuclei were derived from kinetochore-positive displaced chromosomes, kinetochore-positive lagging chromosomes and fragments of broken chromosome bridges in mitosis of MN-free cells. • Kinetochore-positive lagging chromosomes developed into kinetochore-positive micronuclei at the higher frequency than kinetochore-positive displaced chromosomes, kinetochore-negative lagging chromosomes developed into kinetochore-negative micronuclei at the higher rate than kinetochore-negative displaced chromosomes and broken chromosome bridges produced K−MNi and/or K+MNi. - Abstract: Micronuclei (MNi) are extensively used to evaluate genotoxicity and chromosomal instability. Classification of kinetochore-negative (K−MNi) and kinetochore-positive micronuclei (K+MNi) improves the specificity and sensitivity of the micronucleus (MN) test; however, the fundamental differences in the origins of K−MNi and K+MNi have not been addressed due to the limitations of traditional methods. In the current study, HeLa CENP B-GFP H2B-mCherry cells were constructed in which histone 2B (H2B) and centromere protein B (CENP B) were expressed as fusion proteins to monomeric Cherry (mCherry) and EGFP, respectively. MNi were identified using H2B-mCherry; K+MN contained CENP B-GFP, while K−MN did not. Long-term live cell imaging was conducted to examine MN formation in the dual-color fluorescent HeLa cells. The results suggested that K−MNi were derived from kinetochore-negative displaced chromosomes (K−DCs), kinetochore-negative lagging chromosomes (K−LCs) and fragments of broken chromosome bridges (CBs) during late mitotic stages. The results also indicated that K+MNi are derived from kinetochore-positive displaced chromosomes (K

  18. Dynamic imaging of coherent sources reveals different network connectivity underlying the generation and perpetuation of epileptic seizures.

    Directory of Open Access Journals (Sweden)

    Lydia Elshoff

    Full Text Available The concept of focal epilepsies includes a seizure origin in brain regions with hyper synchronous activity (epileptogenic zone and seizure onset zone and a complex epileptic network of different brain areas involved in the generation, propagation, and modulation of seizures. The purpose of this work was to study functional and effective connectivity between regions involved in networks of epileptic seizures. The beginning and middle part of focal seizures from ictal surface EEG data were analyzed using dynamic imaging of coherent sources (DICS, an inverse solution in the frequency domain which describes neuronal networks and coherences of oscillatory brain activities. The information flow (effective connectivity between coherent sources was investigated using the renormalized partial directed coherence (RPDC method. In 8/11 patients, the first and second source of epileptic activity as found by DICS were concordant with the operative resection site; these patients became seizure free after epilepsy surgery. In the remaining 3 patients, the results of DICS / RPDC calculations and the resection site were discordant; these patients had a poorer post-operative outcome. The first sources as found by DICS were located predominantly in cortical structures; subsequent sources included some subcortical structures: thalamus, Nucl. Subthalamicus and cerebellum. DICS seems to be a powerful tool to define the seizure onset zone and the epileptic networks involved. Seizure generation seems to be related to the propagation of epileptic activity from the primary source in the seizure onset zone, and maintenance of seizures is attributed to the perpetuation of epileptic activity between nodes in the epileptic network. Despite of these promising results, this proof of principle study needs further confirmation prior to the use of the described methods in the clinical praxis.

  19. Dynamic Imaging of Coherent Sources Reveals Different Network Connectivity Underlying the Generation and Perpetuation of Epileptic Seizures

    Science.gov (United States)

    Anwar, Abdul Rauf; Deuschl, Günther; Stephani, Ulrich; Raethjen, Jan; Siniatchkin, Michael

    2013-01-01

    The concept of focal epilepsies includes a seizure origin in brain regions with hyper synchronous activity (epileptogenic zone and seizure onset zone) and a complex epileptic network of different brain areas involved in the generation, propagation, and modulation of seizures. The purpose of this work was to study functional and effective connectivity between regions involved in networks of epileptic seizures. The beginning and middle part of focal seizures from ictal surface EEG data were analyzed using dynamic imaging of coherent sources (DICS), an inverse solution in the frequency domain which describes neuronal networks and coherences of oscillatory brain activities. The information flow (effective connectivity) between coherent sources was investigated using the renormalized partial directed coherence (RPDC) method. In 8/11 patients, the first and second source of epileptic activity as found by DICS were concordant with the operative resection site; these patients became seizure free after epilepsy surgery. In the remaining 3 patients, the results of DICS / RPDC calculations and the resection site were discordant; these patients had a poorer post-operative outcome. The first sources as found by DICS were located predominantly in cortical structures; subsequent sources included some subcortical structures: thalamus, Nucl. Subthalamicus and cerebellum. DICS seems to be a powerful tool to define the seizure onset zone and the epileptic networks involved. Seizure generation seems to be related to the propagation of epileptic activity from the primary source in the seizure onset zone, and maintenance of seizures is attributed to the perpetuation of epileptic activity between nodes in the epileptic network. Despite of these promising results, this proof of principle study needs further confirmation prior to the use of the described methods in the clinical praxis. PMID:24194931

  20. Developmental stages and sex differences of white matter and behavioral development through adolescence: a longitudinal diffusion tensor imaging (DTI) study.

    Science.gov (United States)

    Simmonds, Daniel J; Hallquist, Michael N; Asato, Miya; Luna, Beatriz

    2014-05-15

    White matter (WM) continues to mature through adolescence in parallel with gains in cognitive ability. To date, developmental changes in human WM microstructure have been inferred using analyses of cross-sectional or two time-point follow-up studies, limiting our understanding of individual developmental trajectories. The aims of the present longitudinal study were to characterize the timing of WM growth and investigate how sex and behavior are associated with different developmental trajectories. We utilized diffusion tensor imaging (DTI) in 128 individuals aged 8-28, who received annual scans for up to 5 years and completed motor and cognitive tasks. Flexible nonlinear growth curves indicated a hierarchical pattern of WM development. By late childhood, posterior cortical-subcortical connections were similar to adults. During adolescence, WM microstructure reached adult levels, including frontocortical, frontosubcortical and cerebellar connections. Later to mature in adulthood were major corticolimbic association tracts and connections at terminal gray matter sites in cortical and basal ganglia regions. These patterns may reflect adolescent maturation of frontal connectivity supporting cognitive abilities, particularly the protracted refinement of corticolimbic connectivity underlying cognition-emotion interactions. Sex and behavior also played a large role. Males showed continuous WM growth from childhood through early adulthood, whereas females mainly showed growth during mid-adolescence. Further, earlier WM growth in adolescence was associated with faster and more efficient responding and better inhibitory control whereas later growth in adulthood was associated with poorer performance, suggesting that the timing of WM growth is important for cognitive development. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. White matter pathology in Parkinson's disease: The effect of imaging protocol differences and relevance to executive function

    OpenAIRE

    Rae, Charlotte L; Correia, Marta M.; Altena, Ellemarije; Hughes, Laura E.; Barker, Roger A.; Rowe, James B.

    2012-01-01

    Diffusion magnetic resonance imaging is increasingly used as a non-invasive method to investigate white matter structure in neurological and neuropsychiatric disease. However, many options are available for the acquisition sequence and analysis method. Here we used Parkinson's disease as a model neurodegenerative disorder to compare imaging protocols and analysis options. We investigated fractional anisotropy and mean diffusivity of white matter in patients and age-matched controls, comparing...

  2. Different nerve-gliding exercises induce different magnitudes of median nerve longitudinal excursion: an in vivo study using dynamic ultrasound imaging.

    Science.gov (United States)

    Coppieters, Michel W; Hough, Alan D; Dilley, Andrew

    2009-03-01

    Controlled laboratory study using single-group, within-subject comparisons. To determine in an in vivo study whether different types of nerve-gliding exercises are associated with different amounts of longitudinal nerve excursion. Different types of nerve-gliding exercises have been proposed. It is assumed that different exercises produce different amounts of excursion and strain in the peripheral nervous system. Although this has been confirmed in cadaveric experiments, in vivo studies are lacking. High-resolution ultrasound was used to measure longitudinal excursion of the median nerve in the upper arm during 6 different nerve-gliding exercises. Nerve mobilization techniques that involved the elbow and neck were evaluated in 15 asymptomatic volunteers (mean +/- SD age, 30 +/- 8 years). Nerve longitudinal excursion was calculated using a frame-by-frame cross-correlation analysis. A repeated-measures analysis of variance was used to analyze the data. Different exercises induced different amounts of longitudinal nerve excursion (Pneurodynamic techniques have different mechanical effects on the nervous system. Recognition of these differences may assist in the selection of treatment techniques. Having demonstrated differences in mechanical effects, future research will have to evaluate whether these different techniques are also associated with different physiological and therapeutic effects.

  3. High spatial-resolution CE-MRA of the carotid circulation with parallel imaging: comparison of image quality between 2 different acceleration factors at 3.0 Tesla.

    Science.gov (United States)

    Nael, Kambiz; Ruehm, Stefan G; Michaely, Henrik J; Pope, Whitney; Laub, Gerhard; Finn, J Paul; Villablanca, J Pablo

    2006-04-01

    We sought to evaluate and compare the image quality and