WorldWideScience

Sample records for visual reconstruction validation

  1. Reflective Reconstruction of Visual Products

    DEFF Research Database (Denmark)

    Otrel-Cass, Kathrin

    2017-01-01

    of visuals. A case of a New Zealand year 7/8 primary science class studying the water cycle is presented. It is argued that teaching science concepts like the water cycle through visualizations cannot be an abstract endeavor because even when abstract ideas are presented, they are visualized as concrete......This paper presents an argument about the cultural construction of visual products. Based on data from video observations, interviews and the collection of student-produced (visual) artifacts, a material ethnography approach is presented. Applying reflexivity with the use of visuals, the following...

  2. Reflective Reconstruction of Visual Products

    DEFF Research Database (Denmark)

    Otrel-Cass, Kathrin

    2018-01-01

    of visuals. A case of a New Zealand year 7/8 primary science class studying the water cycle is presented. It is argued that teaching science concepts like the water cycle through visualizations cannot be an abstract endeavor because even when abstract ideas are presented, they are visualized as concrete...

  3. Bio-Inspired Sampling and Reconstruction Framework for Scientific Visualization

    Science.gov (United States)

    2015-09-17

    AFRL-AFOSR-VA-TR-2015-0287 Bio -Inspired Sampling and Reconstruction Framework for Scientific Visualization Alireza Entezari UNIVERSITY OF FLORIDA...TITLE AND SUBTITLE A Bio -inspired Sampling and Reconstruction Framework for Scientific Visualization 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9550

  4. The forensic validity of visual analytics

    Science.gov (United States)

    Erbacher, Robert F.

    2008-01-01

    The wider use of visualization and visual analytics in wide ranging fields has led to the need for visual analytics capabilities to be legally admissible, especially when applied to digital forensics. This brings the need to consider legal implications when performing visual analytics, an issue not traditionally examined in visualization and visual analytics techniques and research. While digital data is generally admissible under the Federal Rules of Evidence [10][21], a comprehensive validation of the digital evidence is considered prudent. A comprehensive validation requires validation of the digital data under rules for authentication, hearsay, best evidence rule, and privilege. Additional issues with digital data arise when exploring digital data related to admissibility and the validity of what information was examined, to what extent, and whether the analysis process was sufficiently covered by a search warrant. For instance, a search warrant generally covers very narrow requirements as to what law enforcement is allowed to examine and acquire during an investigation. When searching a hard drive for child pornography, how admissible is evidence of an unrelated crime, i.e. drug dealing. This is further complicated by the concept of "in plain view". When performing an analysis of a hard drive what would be considered "in plain view" when analyzing a hard drive. The purpose of this paper is to discuss the issues of digital forensics and the related issues as they apply to visual analytics and identify how visual analytics techniques fit into the digital forensics analysis process, how visual analytics techniques can improve the legal admissibility of digital data, and identify what research is needed to further improve this process. The goal of this paper is to open up consideration of legal ramifications among the visualization community; the author is not a lawyer and the discussions are not meant to be inclusive of all differences in laws between states and

  5. Visualization and Analysis-Oriented Reconstruction of Material Interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Childs, Henry R.

    2010-03-05

    Reconstructing boundaries along material interfaces from volume fractions is a difficult problem, especially because the under-resolved nature of the input data allows for many correct interpretations. Worse, algorithms widely accepted as appropriate for simulation are inappropriate for visualization. In this paper, we describe a new algorithm that is specifically intended for reconstructing material interfaces for visualization and analysis requirements. The algorithm performs well with respect to memory footprint and execution time, has desirable properties in various accuracy metrics, and also produces smooth surfaces with few artifacts, even when faced with more than two materials per cell.

  6. Three-Dimensional Densitometric Reconstruction and Visualization of Stenosed

    NARCIS (Netherlands)

    van den Broek, J.G.M.; Slump, Cornelis H.; Storm, C.J.; van Benthem, A.C.; Buis, B.

    1995-01-01

    In this paper we report results from an ongoing study about the diagnostic benefits of three-dimensional (3D) visualization and quantification of stenosed coronary artery segments. Biplane angiographic images do not provide enough information for the exact reconstruction of the coronary arteries.

  7. Visual reconstruction of Hampi Temple - Construed Graphically, Pictorially and Digitally

    Directory of Open Access Journals (Sweden)

    Meera Natampally

    2014-05-01

    Full Text Available The existing temple complex in Hampi, Karnataka, India was extensively studied, analyzed and documented. The complex was measured-drawn and digitized by plotting its edges and vertices using AutoCAD to generate 2d drawings. The graphic 2d elements developed were extended into 3 dimensional objects using Google sketch-up. The tool has been used to facilitate the visual re-construction to achieve the architecture of the temple in its original form. 3D virtual modelling / visual reconstruction helps us to visualize the structure in its original form giving a holistic picture of the Vijayanagara Empire in all its former glory. The project is interpreted graphically using Auto-CAD drawings, pictorially, digitally using Sketch-Up model and Kinect.

  8. Nebula: reconstruction and visualization of scattering data in reciprocal space.

    Science.gov (United States)

    Reiten, Andreas; Chernyshov, Dmitry; Mathiesen, Ragnvald H

    2015-04-01

    Two-dimensional solid-state X-ray detectors can now operate at considerable data throughput rates that allow full three-dimensional sampling of scattering data from extended volumes of reciprocal space within second to minute time-scales. For such experiments, simultaneous analysis and visualization allows for remeasurements and a more dynamic measurement strategy. A new software, Nebula, is presented. It efficiently reconstructs X-ray scattering data, generates three-dimensional reciprocal space data sets that can be visualized interactively, and aims to enable real-time processing in high-throughput measurements by employing parallel computing on commodity hardware.

  9. Validation of HEDR models. Hanford Environmental Dose Reconstruction Project

    Energy Technology Data Exchange (ETDEWEB)

    Napier, B.A.; Simpson, J.C.; Eslinger, P.W.; Ramsdell, J.V. Jr.; Thiede, M.E.; Walters, W.H.

    1994-05-01

    The Hanford Environmental Dose Reconstruction (HEDR) Project has developed a set of computer models for estimating the possible radiation doses that individuals may have received from past Hanford Site operations. This document describes the validation of these models. In the HEDR Project, the model validation exercise consisted of comparing computational model estimates with limited historical field measurements and experimental measurements that are independent of those used to develop the models. The results of any one test do not mean that a model is valid. Rather, the collection of tests together provide a level of confidence that the HEDR models are valid.

  10. HEDR model validation plan. Hanford Environmental Dose Reconstruction Project

    Energy Technology Data Exchange (ETDEWEB)

    Napier, B.A.; Gilbert, R.O.; Simpson, J.C.; Ramsdell, J.V. Jr.; Thiede, M.E.; Walters, W.H.

    1993-06-01

    The Hanford Environmental Dose Reconstruction (HEDR) Project has developed a set of computational ``tools`` for estimating the possible radiation dose that individuals may have received from past Hanford Site operations. This document describes the planned activities to ``validate`` these tools. In the sense of the HEDR Project, ``validation`` is a process carried out by comparing computational model predictions with field observations and experimental measurements that are independent of those used to develop the model.

  11. Three-dimensional reconstruction and surface extraction of lower limbs as visualization methodologies of ecchymosis.

    Science.gov (United States)

    de Lima Thomaz, Ricardo; Patrocinio, Ana Claudia; Barbosa Soares, Alcimar

    2014-01-01

    This paper presents a computational system for three-dimensional reconstruction and surface extraction of the human lower limb as a new methodology of visualizing images of multifaceted ecchymosis on the lower limbs. Through standardization of image acquisition by a mechanical system, an algorithm was developed for three-dimensional and surface reconstruction based on the extraction of depth from silhouettes. In order to validate this work, a three-dimensional model of the human lower limb was used inside a virtual environment. At this environment the mechanical procedure of image acquisition was simulated, resulting in 100 images which was later submitted to all algorithms developed. It was observed that the systems for three-dimensional reconstruction and surface extraction of the object were able to generate a new visualization method of the lesion. The results allow us to conclude that the developed systems provided adequate three-dimensional and two-dimensional visualization of the surface of the simulated model. Despite the lack of experiments with real ecchymoses, the systems developed in this work show great potential to be included in the standard methods for the visualization of ecchymoses.

  12. Observation on postoperative binocular visual function reconstruction in intermittent exotropia children with binocular visual training

    Directory of Open Access Journals (Sweden)

    Yan Guo

    2013-07-01

    Full Text Available AIM:To observe the efficacy of the binocular vision training on intermittent exotropia children postoperative binocular visual function reconstruction.METHODS:From January 2010 to October 2011, 112 intermittent exotropia children were treated, divided into three groups, the first group used synoptophore for binocular visual training, the second group used the binocular visual training software for binocular visual training, the third group was control group, no binocular visual training. The postoperative far and near stereoacuity and postoperative 1 year eye position orthophoria rate of the three groups were observed and compared. RESULTS: The two groups of children with visual training, the far and near stereoacuity was significantly higher than that of the control group, the difference was significant. In the 1-year follow-up after surgery, the eye position orthophoria rate of the control group was significantly lower than the other two groups.CONCLUSION: Intermittent exotropia postoperative binocular visual training can significantly promote the reconstruction of children with binocular vision, reduce eye rollback rate, improve the success rate of surgery.

  13. Validation of Functional Performance Tests after Anterior Cruciate Ligament Reconstruction

    Science.gov (United States)

    Kong, Doo Hwan; Yang, Sang Jin; Ha, Jeong Ku; Jang, Seok Hwan; Seo, Jung Gook

    2012-01-01

    Purpose To validate the functional performance tests (FPTs) after anterior cruciate ligament (ACL) reconstruction. Materials and Methods Thirty men in their third decade after ACL reconstruction at 6 month follow-up and thirty healthy subjects were selected. Lysholm knee score, International Knee Documentation Committee (IKDC) subjective score, Tegner activity score, KT-2000 arthrometer test, isokinetic strength test, functional performance tests (one leg hop test, co-contraction test, shuttle run test, carioca test) were performed in two groups. We evaluated the test-retest reliability of FPTs in healthy group and the between FPTs and other parameters in ACL reconstruction group. Results The test-retest result showed high correlation in co-contraction test (r=0.511), shuttle run test (r=0.746), carioca test (r=0.742). In the ACL reconstruction group, the IKDC score, Tegner activity score, extensor power at 60°/s, and one leg hop test also showed high correlation between each test. Conclusions The three FPTs showed correlations with the established methods for determining return to sports activities after ACL reconstruction and had high test-retest reliability. Therefore we believe the three FPTs can be useful methods to assess knee function in athletes after ACL reconstruction. PMID:22570851

  14. Visualization of simulated small vessels on computed tomography using a model-based iterative reconstruction technique.

    Science.gov (United States)

    Higaki, Toru; Tatsugami, Fuminari; Fujioka, Chikako; Sakane, Hiroaki; Nakamura, Yuko; Baba, Yasutaka; Iida, Makoto; Awai, Kazuo

    2017-08-01

    This article describes a quantitative evaluation of visualizing small vessels using several image reconstruction methods in computed tomography. Simulated vessels with diameters of 1-6 mm made by 3D printer was scanned using 320-row detector computed tomography (CT). Hybrid iterative reconstruction (hybrid IR) and model-based iterative reconstruction (MBIR) were performed for the image reconstruction.

  15. Visualization of simulated small vessels on computed tomography using a model-based iterative reconstruction technique

    OpenAIRE

    Toru Higaki; Fuminari Tatsugami; Chikako Fujioka; Hiroaki Sakane; Yuko Nakamura; Yasutaka Baba; Makoto Iida; Kazuo Awai

    2017-01-01

    This article describes a quantitative evaluation of visualizing small vessels using several image reconstruction methods in computed tomography. Simulated vessels with diameters of 1?6?mm made by 3D printer was scanned using 320-row detector computed tomography (CT). Hybrid iterative reconstruction (hybrid IR) and model-based iterative reconstruction (MBIR) were performed for the image reconstruction.

  16. Visualization of simulated small vessels on computed tomography using a model-based iterative reconstruction technique

    Directory of Open Access Journals (Sweden)

    Toru Higaki

    2017-08-01

    Full Text Available This article describes a quantitative evaluation of visualizing small vessels using several image reconstruction methods in computed tomography. Simulated vessels with diameters of 1–6 mm made by 3D printer was scanned using 320-row detector computed tomography (CT. Hybrid iterative reconstruction (hybrid IR and model-based iterative reconstruction (MBIR were performed for the image reconstruction.

  17. Sparse reconstruction of visual appearance for computer graphics and vision

    Science.gov (United States)

    Ramamoorthi, Ravi

    2011-09-01

    A broad range of problems in computer graphics rendering, appearance acquisition for graphics and vision, and imaging, involve sampling, reconstruction, and integration of high-dimensional (4D-8D) signals. For example, precomputation-based real-time rendering of glossy materials and intricate lighting effects like caustics, can involve (pre)-computing the response of the scene to different light and viewing directions, which is often a 6D dataset. Similarly, image-based appearance acquisition of facial details, car paint, or glazed wood, requires us to take images from different light and view directions. Even offline rendering of visual effects like motion blur from a fast-moving car, or depth of field, involves high-dimensional sampling across time and lens aperture. The same problems are also common in computational imaging applications such as light field cameras. In the past few years, computer graphics and computer vision researchers have made significant progress in subsequent analysis and compact factored or multiresolution representations for some of these problems. However, the initial full dataset must almost always still be acquired or computed by brute force. This is often prohibitively expensive, taking hours to days of computation and acquisition time, as well as being a challenge for memory usage and storage. For example, on the order of 10,000 megapixel images are needed for a 1 degree sampling of lights and views for high-frequency materials. We argue that dramatically sparser sampling and reconstruction of these signals is possible, before the full dataset is acquired or simulated. Our key idea is to exploit the structure of the data that often lies in lower-frequency, sparse, or low-dimensional spaces. Our framework will apply to a diverse set of problems such as sparse reconstruction of light transport matrices for relighting, sheared sampling and denoising for offline shadow rendering, time-coherent compressive sampling for appearance

  18. Predictive Validity And Usefulness Of Visual Scanning Task In Hiv ...

    African Journals Online (AJOL)

    To assess the predictive validity of computerized visual scanning test as a tool to screen for presence of brain damage in HIV/AIDS patients. Methods We used a neuropsychological tool, the computerized visual scanning task, a sensitive tool that discriminates between brain-damaged subjects and normal population, ...

  19. Validation of Visual Caries Activity Assessment

    Science.gov (United States)

    Guedes, R.S.; Piovesan, C.; Ardenghi, T.M.; Emmanuelli, B.; Braga, M.M.; Ekstrand, K.R.; Mendes, F.M.

    2014-01-01

    We evaluated the predictive and construct validity of a caries activity assessment system associated with the International Caries Detection and Assessment System (ICDAS) in primary teeth. A total of 469 children were reexamined: participants of a caries survey performed 2 yr before (follow-up rate of 73.4%). At baseline, children (12-59 mo old) were examined with the ICDAS and a caries activity assessment system. The predictive validity was assessed by evaluating the risk of active caries lesion progression to more severe conditions in the follow-up, compared with inactive lesions. We also assessed if children with a higher number of active caries lesions were more likely to develop new lesions (construct validity). Noncavitated active caries lesions at occlusal surfaces presented higher risk of progression than inactive ones. Children with a higher number of active lesions and with higher caries experience presented higher risk of developing new lesions. In conclusion, the caries activity system associated with the ICDAS presents predictive and construct validity in primary teeth in the assessment of occlusal caries lesions, but predictive validity was not observed in smooth surfaces. PMID:24713370

  20. Validation of Visual Caries Activity Assessment

    DEFF Research Database (Denmark)

    Guedes, R S; Piovesan, C; Ardenghi, T M

    2014-01-01

    We evaluated the predictive and construct validity of a caries activity assessment system associated with the International Caries Detection and Assessment System (ICDAS) in primary teeth. A total of 469 children were reexamined: participants of a caries survey performed 2 yr before (follow-up rate...... of 73.4%). At baseline, children (12-59 mo old) were examined with the ICDAS and a caries activity assessment system. The predictive validity was assessed by evaluating the risk of active caries lesion progression to more severe conditions in the follow-up, compared with inactive lesions. We also...... assessed if children with a higher number of active caries lesions were more likely to develop new lesions (construct validity). Noncavitated active caries lesions at occlusal surfaces presented higher risk of progression than inactive ones. Children with a higher number of active lesions and with higher...

  1. Reconstructing, Investigating the Reliability and Validity and Scoring the Stanford Diagnostic Reading Test

    Directory of Open Access Journals (Sweden)

    Bahram Saleh Sedghpour

    2012-10-01

    Full Text Available Objectives: The aim of the present study was to reconstruct determining validity, and score The Stanford Diagnostic Reading Test fourth edition (SDRT4 in the sixth grade students. Methods: The population of the study was all sixth grades of the 19 educational districts from Tehran, 571 students (255 boys and 316 girls were selected by using a random multi-cluster sampling. The data were analyzed. The techniques were item analysis (difficulty index, discriminative index, and loop techniques. Validity, translation validity, content validity, and construct validity (factorial analysis, and reliability (Kuder-Richardson. Results: The exploratory factor analysis determined five factors: declarative knowledge, inferential knowledge, procedural knowledge and visualization knowledge. The reliability of the Stanford diagnostic Reading Test’s subtests by computing the Kuder-Richardson coefficient were 0.778, 0.732 and 0.748 for comprehension subtest, vocabulary subtest and scanning subtest in order. Discussion: By considering the results of present study, SDRT4 has good reliability and validity and can appropriately diagnose the reading disabled students in the sixth grade.

  2. Reinterpretation in visual imagery is possible without visual cues: a validation of previous research.

    Science.gov (United States)

    Kamermans, Kevin L; Pouw, Wim; Mast, Fred W; Paas, Fred

    2017-12-14

    Is visual reinterpretation of bistable figures (e.g., duck/rabbit figure) in visual imagery possible? Current consensus suggests that it is in principle possible because of converging evidence of quasi-pictorial functioning of visual imagery. Yet, studies that have directly tested and found evidence for reinterpretation in visual imagery, allow for the possibility that reinterpretation was already achieved during memorization of the figure(s). One study resolved this issue, providing evidence for reinterpretation in visual imagery (Mast and Kosslyn, Cognition 86:57-70, 2002). However, participants in that study performed reinterpretations with aid of visual cues. Hence, reinterpretation was not performed with mental imagery alone. Therefore, in this study we assessed the possibility of reinterpretation without visual support. We further explored the possible role of haptic cues to assess the multimodal nature of mental imagery. Fifty-three participants were consecutively presented three to be remembered bistable 2-D figures (reinterpretable when rotated 180°), two of which were visually inspected and one was explored hapticly. After memorization of the figures, a visually bistable exemplar figure was presented to ensure understanding of the concept of visual bistability. During recall, 11 participants (out of 36; 30.6%) who did not spot bistability during memorization successfully performed reinterpretations when instructed to mentally rotate their visual image, but additional haptic cues during mental imagery did not inflate reinterpretation ability. This study validates previous findings that reinterpretation in visual imagery is possible.

  3. A Visual Framework for Digital Reconstruction of Topographic Maps

    KAUST Repository

    Thabet, Ali Kassem

    2014-09-30

    We present a framework for reconstructing Digital Elevation Maps (DEM) from scanned topographic maps. We first rectify the images to ensure that maps fit together without distortion. To segment iso-contours, we have developed a novel semi-automated method based on mean-shifts that requires only minimal user interaction. Contour labels are automatically read using an OCR module. To reconstruct the output DEM from scattered data, we generalize natural neighbor interpolation to handle the transfinite case (contours and points). To this end, we use parallel vector propagation to compute a discrete Voronoi diagram of the constraints, and a modified floodfill to compute virtual Voronoi tiles. Our framework is able to handle tens of thousands of contours and points and can generate DEMs comprising more than 100 million samples. We provide quantitative comparison to commercial software and show the benefits of our approach. We furthermore show the robustness of our method on a massive set of old maps predating satellite acquisition. Compared to other methods, our framework is able to accurately and efficiently generate a final DEM despite inconsistencies, sparse or missing contours even for highly complex and cluttered maps. Therefore, this method has broad applicability for digitization and reconstruction of the world\\'s old topographic maps that are often the only record of past landscapess and cultural heritage before their destruction under modern development.

  4. The validity of proximal caries detection using magnifying visual aids.

    Science.gov (United States)

    Haak, Rainer; Wicht, Michael J; Hellmich, Martin; Gossmann, Andrea; Noack, Michael J

    2002-01-01

    The purpose of this study was to determine the validity of proximal caries detection supported by a prism loupe and a surgical microscope used by examiners having different professional experience. One hundred and sixty extracted premolars and molars with varying degrees of proximal caries or sound surfaces were embedded in 10 pairs of models with proximal tooth contacts and a simulated gingiva mask. The proximal surfaces were visually evaluated by 14 observers (7 students, 7 dentists) according to a 5-point caries rating scale using a head-worn prism loupe (x4.5), a surgical microscope (x 14) and without any magnifying device (control). The validity of observations was expressed as ROC curves calculated for two gold standard thresholds: (a) the presence of caries and (b) macroscopic cavitation. Repeated measures analysis of variance was used to determine the effects of 'observer group' and 'diagnostic modality'. An influence of the observer group could not be demonstrated (p > 0.72), whereas significant differences were revealed between the diagnostic modalities (p caries detection with magnifying aids were smaller compared to the control group. It was concluded that the use of a prism loupe or a surgical microscope does not improve the validity of proximal caries detection if the operators, irrespective of being dental students or clinical instructors, are inexperienced in its utilisation. In general only moderate validity was achieved with visual inspection of proximal sites. Copyright 2002 S. Karger AG, Basel

  5. Validation of an instrument to assess visual ability in children with visual impairment in China.

    Science.gov (United States)

    Huang, Jinhai; Khadka, Jyoti; Gao, Rongrong; Zhang, Sifang; Dong, Wenpeng; Bao, Fangjun; Chen, Haisi; Wang, Qinmei; Chen, Hao; Pesudovs, Konrad

    2017-04-01

    To validate a visual ability instrument for school-aged children with visual impairment in China by translating, culturally adopting and Rasch scaling the Cardiff Visual Ability Questionnaire for Children (CVAQC). The 25-item CVAQC was translated into Mandarin using a standard protocol. The translated version (CVAQC-CN) was subjected to cognitive testing to ensure a proper cultural adaptation of its content. Then, the CVAQC-CN was interviewer-administered to 114 school-aged children and young people with visual impairment. Rasch analysis was carried out to assess its psychometric properties. The correlation between the CVAQC-CN visual ability scores and clinical measure of vision (visual acuity; VA and contrast sensitivity, CS) were assessed using Spearman's r. Based on cultural adaptation exercise, cognitive testing, missing data and Rasch metrics-based iterative item removal, three items were removed from the original 25. The 22-item CVAQC-CN demonstrated excellent measurement precision (person separation index, 3.08), content validity (item separation, 10.09) and item reliability (0.99). Moreover, the CVAQC-CN was unidimensional and had no item bias. The person-item map indicated good targeting of item difficulty to person ability. The CVAQC-CN had moderate correlations between CS (-0.53, pvisual ability in children with visual impairment in China. The instrument can be used as a clinical and research outcome measure to assess the change in visual ability after low vision rehabilitation intervention. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  6. Brachial plexus 3D reconstruction from MRI with dissection validation: a baseline study for clinical applications.

    Science.gov (United States)

    Van de Velde, Joris; Bogaert, Stephanie; Vandemaele, Pieter; Huysse, Wouter; Achten, Eric; Leijnse, Joris; De Neve, Wilfried; Van Hoof, Tom

    2016-03-01

    The present study aimed to establish a baseline for detailed 3D brachial plexus reconstruction from magnetic resonance imaging (MRI). Concretely, the goal was to determine the individual brachial plexus anatomy with maximum detail and accuracy achievable, as yet irrespective of whether the methods used could be economically and practically applied in the clinical setting. Six embalmed cadavers were randomly taken for MRI imaging of the brachial plexus. Detailed two-dimensional (2D) segmentation for all brachial plexus parts was done. The 2D brachial plexus segmentations were 3D reconstructed using Mimics(®) software. Then, these 3D reconstructions were anatomically validated by dissection of the cadavers. After finalising the cadaver experiments, brachial plexus MRIs were obtained in three healthy male volunteers and the same reconstruction procedure as in vitro was followed. A procedure was developed for brachial plexus 3D reconstruction based on MRI without the use of any contrast agent. Anatomical validation of six cadaver brachial plexus reconstructions showed high correspondence with the dissected brachial plexuses. Anatomical variations of the main branches were equally present in the 3D reconstructions generated. However, there were also some differences that related to the difference between the surface anatomy of the nerve and the internal nerve structure. In vivo, it was possible to reconstruct the complete brachial plexus in such a manner that normal-appearing BPs were derived in a reproducible way. This study showed that the described procedure results in accurate and reproducible brachial plexus 3D reconstructions.

  7. 3D visualization for medical volume segmentation validation

    Science.gov (United States)

    Eldeib, Ayman M.

    2002-05-01

    This paper presents a 3-D visualization tool that manipulates and/or enhances by user input the segmented targets and other organs. A 3-D visualization tool is developed to create a precise and realistic 3-D model from CT/MR data set for manipulation in 3-D and permitting physician or planner to look through, around, and inside the various structures. The 3-D visualization tool is designed to assist and to evaluate the segmentation process. It can control the transparency of each 3-D object. It displays in one view a 2-D slice (axial, coronal, and/or sagittal)within a 3-D model of the segmented tumor or structures. This helps the radiotherapist or the operator to evaluate the adequacy of the generated target compared to the original 2-D slices. The graphical interface enables the operator to easily select a specific 2-D slice of the 3-D volume data set. The operator is enabled to manually override and adjust the automated segmentation results. After correction, the operator can see the 3-D model again and go back and forth till satisfactory segmentation is obtained. The novelty of this research work is in using state-of-the-art of image processing and 3-D visualization techniques to facilitate a process of a medical volume segmentation validation and assure the accuracy of the volume measurement of the structure of interest.

  8. Exploring Childhood Memories with Adult Survivors of Sexual Abuse: Concrete Reconstruction and Visualization Techniques.

    Science.gov (United States)

    Roland, Catherine B.

    1993-01-01

    Describes two memory-enhancing techniques, visualization and concrete reconstruction, that have been successful in counseling adult survivors of sexual abuse. Includes suggested implementations, case examples, and implications for incorporating memory techniques into counseling process. Describes various risk factors involved in using these…

  9. Reconstruction methods for sound visualization based on acousto-optic tomography

    DEFF Research Database (Denmark)

    Torras Rosell, Antoni; Lylloff, Oliver; Barrera Figueroa, Salvador

    2013-01-01

    , the interaction between sound and light, over an aperture where the acoustic field is to be investigated. By identifying the relationship between the apparent velocity of the LDV and the Radon transform of the acoustic field, it is possible to reconstruct the sound pressure distribution of the scanned area using...... tomographic techniques. The filtered back projection (FBP) method is the most popular reconstruction algorithm used for tomography in many fields of science. The present study takes the performance of the FBP method in sound visualization as a reference and investigates the use of alternative methods commonly......The visualization of acoustic fields using acousto-optic tomography has recently proved to yield satisfactory results in the audible frequency range. The current implementation of this visualization technique uses a laser Doppler vibrometer (LDV) to measure the acousto-optic effect, that is...

  10. Standard anatomical and visual space for the mouse retina: computational reconstruction and transformation of flattened retinae with the Retistruct package.

    Directory of Open Access Journals (Sweden)

    David C Sterratt

    Full Text Available The concept of topographic mapping is central to the understanding of the visual system at many levels, from the developmental to the computational. It is important to be able to relate different coordinate systems, e.g. maps of the visual field and maps of the retina. Retinal maps are frequently based on flat-mount preparations. These use dissection and relaxing cuts to render the quasi-spherical retina into a 2D preparation. The variable nature of relaxing cuts and associated tears limits quantitative cross-animal comparisons. We present an algorithm, "Retistruct," that reconstructs retinal flat-mounts by mapping them into a standard, spherical retinal space. This is achieved by: stitching the marked-up cuts of the flat-mount outline; dividing the stitched outline into a mesh whose vertices then are mapped onto a curtailed sphere; and finally moving the vertices so as to minimise a physically-inspired deformation energy function. Our validation studies indicate that the algorithm can estimate the position of a point on the intact adult retina to within 8° of arc (3.6% of nasotemporal axis. The coordinates in reconstructed retinae can be transformed to visuotopic coordinates. Retistruct is used to investigate the organisation of the adult mouse visual system. We orient the retina relative to the nictitating membrane and compare this to eye muscle insertions. To align the retinotopic and visuotopic coordinate systems in the mouse, we utilised the geometry of binocular vision. In standard retinal space, the composite decussation line for the uncrossed retinal projection is located 64° away from the retinal pole. Projecting anatomically defined uncrossed retinal projections into visual space gives binocular congruence if the optical axis of the mouse eye is oriented at 64° azimuth and 22° elevation, in concordance with previous results. Moreover, using these coordinates, the dorsoventral boundary for S-opsin expressing cones closely matches

  11. Sensor data validation and reconstruction in water networks : a methodology and software implementation

    OpenAIRE

    García Valverde, Diego; Quevedo Casín, Joseba Jokin; Puig Cayuela, Vicenç; Cugueró Escofet, Miquel Àngel

    2014-01-01

    In this paper, a data validation and reconstruction methodology that can be applied to the sensors used for real-time monitoring in water networks is presented. On the one hand, a validation approach based on quality levels is described to detect potential invalid and missing data. On the other hand, the reconstruction strategy is based on a set of temporal and spatial models used to estimate missing/invalid data with the model estimation providing the best fit. A software tool implementing t...

  12. The Convolutional Visual Network for Identification and Reconstruction of NOvA Events

    Energy Technology Data Exchange (ETDEWEB)

    Psihas, Fernanda [Indiana U.

    2017-11-22

    In 2016 the NOvA experiment released results for the observation of oscillations in the vμ and ve channels as well as ve cross section measurements using neutrinos from Fermilab’s NuMI beam. These and other measurements in progress rely on the accurate identification and reconstruction of the neutrino flavor and energy recorded by our detectors. This presentation describes the first application of convolutional neural network technology for event identification and reconstruction in particle detectors like NOvA. The Convolutional Visual Network (CVN) Algorithm was developed for identification, categorization, and reconstruction of NOvA events. It increased the selection efficiency of the ve appearance signal by 40% and studies show potential impact to the vμ disappearance analysis.

  13. CVN A Convolutional Visual Network for Identication and Reconstruction of NOvA Events

    Science.gov (United States)

    Psihas, Fernanda; NOvA Collaboration

    2017-09-01

    In the past year, the NOvA experiment released results for the observation of neutrino oscillations in the νμ and νe channels as well as νe cross section measurements using neutrinos from Fermilab’s NuMI beam. These and other measurements in progress rely on the accurate identication and reconstruction of the neutrino avor and energy recorded by our detectors. This presentation describes the rst application of convolutional neural network technology for event identication and reconstruction in particle detectors such as NOvA. The Convolutional Visual Network (CVN) Algorithm was developed for identication, categorization, and reconstruction of NOvA events. It increased the selection efficiency of the νe appearance signal by 40% and studies show potential impact to the νμ disappearance analysis.

  14. The Convolutional Visual Network for Identification and Reconstruction of NOvA Events

    Science.gov (United States)

    Psihas, Fernanda; NOvA Collaboration

    2017-10-01

    In 2016 the NOvA experiment released results for the observation of oscillations in the vμ and ve channels as well as ve cross section measurements using neutrinos from Fermilab’s NuMI beam. These and other measurements in progress rely on the accurate identification and reconstruction of the neutrino flavor and energy recorded by our detectors. This presentation describes the first application of convolutional neural network technology for event identification and reconstruction in particle detectors like NOvA. The Convolutional Visual Network (CVN) Algorithm was developed for identification, categorization, and reconstruction of NOvA events. It increased the selection efficiency of the ve appearance signal by 40% and studies show potential impact to the vμ disappearance analysis.

  15. Images from the Mind: BCI image reconstruction based on Rapid Serial Visual Presentations of polygon primitives

    Directory of Open Access Journals (Sweden)

    Luís F Seoane

    2015-04-01

    Full Text Available We provide a proof of concept for an EEG-based reconstruction of a visual image which is on a user's mind. Our approach is based on the Rapid Serial Visual Presentation (RSVP of polygon primitives and Brain-Computer Interface (BCI technology. In an experimental setup, subjects were presented bursts of polygons: some of them contributed to building a target image (because they matched the shape and/or color of the target while some of them did not. The presentation of the contributing polygons triggered attention-related EEG patterns. These Event Related Potentials (ERPs could be determined using BCI classification and could be matched to the stimuli that elicited them. These stimuli (i.e. the ERP-correlated polygons were accumulated in the display until a satisfactory reconstruction of the target image was reached. As more polygons were accumulated, finer visual details were attained resulting in more challenging classification tasks. In our experiments, we observe an average classification accuracy of around 75%. An in-depth investigation suggests that many of the misclassifications were not misinterpretations of the BCI concerning the users' intent, but rather caused by ambiguous polygons that could contribute to reconstruct several different images. When we put our BCI-image reconstruction in perspective with other RSVP BCI paradigms, there is large room for improvement both in speed and accuracy. These results invite us to be optimistic. They open a plethora of possibilities to explore non-invasive BCIs for image reconstruction both in healthy and impaired subjects and, accordingly, suggest interesting recreational and clinical applications.

  16. Validity of occupational stress assessment using a visual analogue scale.

    Science.gov (United States)

    Lesage, F X; Berjot, S

    2011-09-01

    The visual analogue scale (VAS) is empirically used by occupational physicians to assess stress but very few studies have been published about its quantitative validation. To assess the external validity of the VAS for the assessment of stress in the clinical occupational health setting by comparing its scores with the Perceived Stress Scale (PSS) of Cohen. An anonymous self-completed questionnaire (PSS14) and the VAS were filled in by a random sample of 360 workers from several occupational health centres. No difference between the mean scores of PSS14 and stress VAS was found. The equation of the linear regression was 'VAS score = -0.18 + 1008 × PSS14 score'. A VAS score of 7.0 was identified as having the best sensitivity/specificity ratio (0.74 and 0.93, respectively) for identifying those with 'high stress' using the PSS cut-off score of 7.2, using a receiver operator curve approach. Our results support an acceptable agreement between the two tests, meaning that the two tools assess the same psychological construct. The good sensitivity/specificity ratio and the area under the curve close to 1 provide evidence that a VAS is suitable to help the occupational physician detect a high level of stress. The use of a VAS for stress assessment seems to be meaningful, suitable and useful for occupational physicians.

  17. Recovery and Visualization of 3D Structure of Chromosomes from Tomographic Reconstruction Images

    Directory of Open Access Journals (Sweden)

    Tsap Leonid V

    2006-01-01

    Full Text Available The objectives of this work include automatic recovery and visualization of a 3D chromosome structure from a sequence of 2D tomographic reconstruction images taken through the nucleus of a cell. Structure is very important for biologists as it affects chromosome functions, behavior of the cell, and its state. Analysis of chromosome structure is significant in the detection of diseases, identification of chromosomal abnormalities, study of DNA structural conformation, in-depth study of chromosomal surface morphology, observation of in vivo behavior of the chromosomes over time, and in monitoring environmental gene mutations. The methodology incorporates thresholding based on a histogram analysis with a polyline splitting algorithm, contour extraction via active contours, and detection of the 3D chromosome structure by establishing corresponding regions throughout the slices. Visualization using point cloud meshing generates a 3D surface. The 3D triangular mesh of the chromosomes provides surface detail and allows a user to interactively analyze chromosomes using visualization software.

  18. Recovery and Visualization of 3D Structure of Chromosomes from Tomographic Reconstruction Images

    Energy Technology Data Exchange (ETDEWEB)

    Babu, S; Liao, P; Shin, M C; Tsap, L V

    2004-04-28

    The objectives of this work include automatic recovery and visualization of a 3D chromosome structure from a sequence of 2D tomographic reconstruction images taken through the nucleus of a cell. Structure is very important for biologists as it affects chromosome functions, behavior of the cell and its state. Chromosome analysis is significant in the detection of deceases and in monitoring environmental gene mutations. The algorithm incorporates thresholding based on a histogram analysis with a polyline splitting algorithm, contour extraction via active contours, and detection of the 3D chromosome structure by establishing corresponding regions throughout the slices. Visualization using point cloud meshing generates a 3D surface. The 3D triangular mesh of the chromosomes provides surface detail and allows a user to interactively analyze chromosomes using visualization software.

  19. CT x-ray tube voltage optimisation and image reconstruction evaluation using visual grading analysis

    Science.gov (United States)

    Zheng, Xiaoming; Kim, Ted M.; Davidson, Rob; Lee, Seongju; Shin, Cheongil; Yang, Sook

    2014-03-01

    The purposes of this work were to find an optimal x-ray voltage for CT imaging and to determine the diagnostic effectiveness of image reconstruction techniques by using the visual grading analysis (VGA). Images of the PH-5 CT abdomen phantom (Kagaku Co, Kyoto) were acquired by the Toshiba Aquillion One 320 slices CT system with various exposures (from 10 to 580 mAs) under different tube peak voltages (80, 100 and 120 kVp). The images were reconstructed by employing the FBP and the AIDR 3D iterative reconstructions with Mild, Standard and Strong FBP blending. Image quality was assessed by measuring noise, contrast to noise ratio and human observer's VGA scores. The CT dose index CTDIv was obtained from the values displayed on the images. The best fit for the curves of the image quality VGA vs dose CTDIv is a logistic function from the SPSS estimation. A threshold dose Dt is defined as the CTDIv at the just acceptable for diagnostic image quality and a figure of merit (FOM) is defined as the slope of the standardised logistic function. The Dt and FOM were found to be 5.4, 8.1 and 9.1 mGy and 0.47, 0.51 and 0.38 under the tube voltages of 80, 100 and 120 kVp, respectively, from images reconstructed by the FBP technique. The Dt and FOM values were lower from the images reconstructed by the AIDR 3D in comparison with the FBP technique. The optimal xray peak voltage for the imaging of the PH-5 abdomen phantom by the Aquillion One CT system was found to be at 100 kVp. The images reconstructed by the FBP are more diagnostically effective than that by the AIDR 3D but with a higher dose Dt to the patients.

  20. Toward the Validation of Visual Analogue Scale for Anxiety

    Science.gov (United States)

    Facco, E.; Zanette, G.; Favero, L.; Bacci, C.; Sivolella, S.; Cavallin, F.; Manani, G.

    2011-01-01

    Anxiety is a relevant problem in dental practice. The Visual Analogue Scale for Anxiety (VAS‐A), introduced in dentistry in 1988, has not yet been validated in large series. The aim of this study is to check VAS‐A effectiveness in more than 1000 patients submitted to implantology. The VAS‐A and the Dental Anxiety Scale (DAS) were administered preoperatively to 1114 patients (459 males and 655 females, age 54.7 ± 13.1 years). Statistical analysis was conducted with Pearson correlation coefficient, the receiver operating characteristic (ROC) curve, and McNemar tests. A close correlation between DAS and VAS‐A was found (r  =  0.57, P anxiety and phobia were 5.1 and 7.0 cm, respectively. Despite a significant concordance of tests in 800 cases (72%), disagreement was found in the remaining 314 cases (28%), and low DAS was associated with high VAS‐A (230 cases) or vice versa (84 cases). Our study confirms that VAS‐A is a simple, sensitive, fast, and reliable tool in dental anxiety assessment. The rate of disagreement between VAS‐A and DAS is probably due to different test sensitivities to different components of dental anxiety. VAS‐A can be used effectively in the assessment of dental patients, using the values of 5.1 cm and 7.0 cm as cutoff values for anxiety and phobia, respectively. PMID:21410359

  1. Visualized Evaluation of Blood Flow to the Gastric Conduit and Complications in Esophageal Reconstruction.

    Science.gov (United States)

    Noma, Kazuhiro; Shirakawa, Yasuhiro; Kanaya, Nobuhiko; Okada, Tsuyoshi; Maeda, Naoaki; Ninomiya, Takayuki; Tanabe, Shunsuke; Sakurama, Kazufumi; Fujiwara, Toshiyoshi

    2018-03-01

    Evaluation of the blood supply to gastric conduits is critically important to avoid complications after esophagectomy. We began visual evaluation of blood flow using indocyanine green (ICG) fluorescent imaging in July 2015, to reduce reconstructive complications. In this study, we aimed to statistically verify the efficacy of blood flow evaluation using our simplified ICG method. A total of 285 consecutive patients who underwent esophagectomy and gastric conduit reconstruction were reviewed and divided into 2 groups: before and after introduction of ICG evaluation. The entire cohort and 68 patient pairs after propensity score matching (PS-M) were evaluated for clinical outcomes and the effect of visualized evaluation on reducing the risk of complication. The leakage rate in the ICG group was significantly lower than in the non-ICG group for each severity grade, both in the entire cohort (285 subjects) and after PS-M; the rates of other major complications, including recurrent laryngeal nerve palsy and pneumonia, were not different. The duration of postoperative ICU stay was approximately 1 day shorter in the ICG group than in the non-ICG group in the entire cohort, and approximately 2 days shorter after PS-M. Visualized evaluation of blood flow with ICG methods significantly reduced the rate of anastomotic complications of all Clavien-Dindo (CD) grades. Odds ratios for ICG evaluation decreased with CD grade (0.3419 for CD ≥ 1; 0.241 for CD ≥ 2; and 0.2153 for CD ≥ 3). Objective evaluation of blood supply to the reconstructed conduit using ICG fluorescent imaging reduces the risk and degree of anastomotic complication. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  2. Optimizing the reconstruction filter in cone-beam CT to improve periodontal ligament space visualization: An in vitro study

    Energy Technology Data Exchange (ETDEWEB)

    Houno, Yuuki; Kodera, Yoshie [Graduate School of Medicine, Nagoya University, Nagoya (Japan); Hishikawa, Toshimitsu; Naitoh, Munetaka; Mitani, Akio; Noguchi, Toshihide; Ariji, Eiichiro [Aichi Gakuin University, Nisshin (Japan); Gotoh, Kenichi [Div. of Radiology, Dental Hospital, Aichi Gakuin University, Nisshin (Japan)

    2017-09-15

    Evaluation of alveolar bone is important in the diagnosis of dental diseases. The periodontal ligament space is difficult to clearly depict in cone-beam computed tomography images because the reconstruction filter conditions during image processing cause image blurring, resulting in decreased spatial resolution. We examined different reconstruction filters to assess their ability to improve spatial resolution and allow for a clearer visualization of the periodontal ligament space. Cone-beam computed tomography projections of 2 skull phantoms were reconstructed using 6 reconstruction conditions and then compared using the Thurstone paired comparison method. Physical evaluations, including the modulation transfer function and the Wiener spectrum, as well as an assessment of space visibility, were undertaken using experimental phantoms. Image reconstruction using a modified Shepp-Logan filter resulted in better sensory, physical, and quantitative evaluations. The reconstruction conditions substantially improved the spatial resolution and visualization of the periodontal ligament space. The difference in sensitivity was obtained by altering the reconstruction filter. Modifying the characteristics of a reconstruction filter can generate significant improvement in assessments of the periodontal ligament space. A high-frequency enhancement filter improves the visualization of thin structures and will be useful when accurate assessment of the periodontal ligament space is necessary.

  3. Visually Induced Dizziness in Children and Validation of the Pediatric Visually Induced Dizziness Questionnaire

    Directory of Open Access Journals (Sweden)

    Marousa Pavlou

    2017-12-01

    Full Text Available AimsTo develop and validate the Pediatric Visually Induced Dizziness Questionnaire (PVID and quantify the presence and severity of visually induced dizziness (ViD, i.e., symptoms induced by visual motion stimuli including crowds and scrolling computer screens in children.Methods169 healthy (female n = 89; recruited from mainstream schools, London, UK and 114 children with a primary migraine, concussion, or vestibular disorder diagnosis (female n = 62, aged 6–17 years, were included. Children with primary migraine were recruited from mainstream schools while children with concussion or vestibular disorder were recruited from tertiary balance centers in London, UK, and Pittsburgh, PA, USA. Children completed the PVID, which assesses the frequency of dizziness and unsteadiness experienced in specific environmental situations, and Strength and Difficulties Questionnaire (SDQ, a brief behavioral screening instrument.ResultsThe PVID showed high internal consistency (11 items; α = 0.90. A significant between-group difference was noted with higher (i.e., worse PVID scores for patients vs. healthy participants (U = 2,436.5, z = −10.719, p < 0.001; a significant difference was noted between individual patient groups [χ2(2 = 11.014, p = 0.004] but post hoc analysis showed no significant pairwise comparisons. The optimal cut-off score for discriminating between individuals with and without abnormal ViD levels was 0.45 out of 3 (sensitivity 83%, specificity 75%. Self-rated emotional (U = 2,730.0, z = −6.169 and hyperactivity (U = 3,445.0, z = −4.506 SDQ subscale as well as informant (U = 188.5, z = −3.916 and self-rated (U = 3,178.5, z = −5.083 total scores were significantly worse for patients compared to healthy participants (p < 0.001.ConclusionViD is common in children with a primary concussion, migraine, or vestibular diagnosis. The PVID is a valid measure for

  4. Reconstruction of Mandible: A Fully Digital Workflow From Visualized Iliac Bone Grafting to Implant Restoration.

    Science.gov (United States)

    Tian, Taoran; Zhang, Tao; Ma, Quanquan; Zhang, Qi; Cai, Xiaoxiao

    2017-07-01

    Although digital aids can help surgeons compensate for the shortcomings of traditional mandibular reconstruction techniques to perform surgery more precisely and effectively, the use of these digital techniques has often been fragmented, divided, and incomplete. This article describes the workflow of a fully digital mandibular reconstruction to explore the proper indications and discusses innovations based on the accuracy and effectiveness of digital techniques. A restoration-oriented mandibular reconstruction was performed by applying different digital techniques. Preoperative virtual surgery and rapid prototyping were used to aid the vascularized iliac bone graft surgery, which offered a solid basis for the ensuing treatment. Subsequently, implant rehabilitation was accomplished with the assistance of computer-assisted design and manufacture, laser treatment, and selective laser melting techniques. The workflow of the fully digital mandibular reconstruction successfully achieved a restoration-oriented treatment. These predictable, accurate, and effective digital techniques improved the consistency of pretreatment design and follow-up treatment. The treatment sequence achieved high predictability and reproducibility owing to the use of digital techniques. This study shows that a digital workflow can be predictable, accurate, and effective, which suggests that it could be a valid digital protocol for developing a treatment sequence for patients with jaw defects caused by trauma, congenital anomalies, or mandibular tumor resection. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  5. Validity of proxy data obtained by different psychological autopsy information reconstruction techniques.

    Science.gov (United States)

    Fang, L; Zhang, J

    2010-01-01

    Two informants were interviewed for each of 416 living controls (individuals sampled from the normal population) interviewed in a Chinese case-control psychological autopsy study. The validity of proxy data, obtained using seven psychological autopsy information reconstruction techniques (types 1, 2 and A - E), was evaluated, with living controls' self reports used as the gold-standard. Proxy data for reconstruction technique types 1, 2 and D on the Impulsivity Inventory Scale (total impulsivity score) were no different from the living controls' self report gold standard, whereas data for types A and E were smaller than data from living controls. On the 'acceptance or resignation' sub-scale of the avoidance coping dimension of the Moos Coping Response Inventory, information obtained by reconstruction technique types 1 and D was not significantly different from the living controls' self reports, whereas proxy data from types 2, A and E were smaller than those from the living controls. No statistically significant differences were identified for other proxy data obtained by reconstruction technique types 1, 2, A, D and E. These results indicate that using a second informant does not significantly enhance information reconstruction for the target.

  6. Reconstructing the recent visual past: Hierarchical knowledge-based effects in visual working memory.

    Science.gov (United States)

    Poirier, Marie; Heussen, Daniel; Aldrovandi, Silvio; Daniel, Lauren; Tasnim, Saiyara; Hampton, James A

    2017-12-01

    This paper presents two experiments that examine the influence of multiple levels of knowledge on visual working memory (VWM). Experiment 1 focused on memory for faces. Faces were selected from continua that were constructed by morphing two face photographs in 100 steps; half of the continua morphed a famous face into an unfamiliar one, while the other half used two unfamiliar faces. Participants studied six sequentially presented faces each from a different continuum, and at test they had to locate one of these within its continuum. Experiment 2 examined immediate memory for object sizes. On each trial, six images were shown; these were either all vegetables or all random shapes. Immediately after each list, one item was presented again, in a new random size, and participants reproduced its studied size. Results suggested that two levels of knowledge influenced VWM. First, there was an overall central-tendency bias whereby items were remembered as being closer to the overall average or central tokens (averaged across items and trials) than they actually were. Second, when object knowledge was available for the to-be-remembered items (i.e., famous face or typical size of a vegetable) a further bias was introduced in responses. The results extend the findings of Hemmer and Steyvers (Psychonomic Bulletin & Review, 16, 80-87, 2009a) from episodic memory to VWM and contribute to the growing literature which illustrates the complexity and flexibility of the representations subtending VWM performance (e.g., Bae, Olkkonen, Allred, & Flombaum, Journal of Experimental Psychology: General, 144(4):744-63, 2015).

  7. GPU-accelerated brain connectivity reconstruction and visualization in large-scale electron micrographs

    KAUST Repository

    Jeong, Wonki

    2011-01-01

    This chapter introduces a GPU-accelerated interactive, semiautomatic axon segmentation and visualization system. Two challenging problems have been addressed: the interactive 3D axon segmentation and the interactive 3D image filtering and rendering of implicit surfaces. The reconstruction of neural connections to understand the function of the brain is an emerging and active research area in neuroscience. With the advent of high-resolution scanning technologies, such as 3D light microscopy and electron microscopy (EM), reconstruction of complex 3D neural circuits from large volumes of neural tissues has become feasible. Among them, only EM data can provide sufficient resolution to identify synapses and to resolve extremely narrow neural processes. These high-resolution, large-scale datasets pose challenging problems, for example, how to process and manipulate large datasets to extract scientifically meaningful information using a compact representation in a reasonable processing time. The running time of the multiphase level set segmentation method has been measured on the CPU and GPU. The CPU version is implemented using the ITK image class and the ITK distance transform filter. The numerical part of the CPU implementation is similar to the GPU implementation for fair comparison. The main focus of this chapter is introducing the GPU algorithms and their implementation details, which are the core components of the interactive segmentation and visualization system. © 2011 Copyright © 2011 NVIDIA Corporation and Wen-mei W. Hwu Published by Elsevier Inc. All rights reserved..

  8. Reconstructions of information in visual spatial working memory degrade with memory load.

    Science.gov (United States)

    Sprague, Thomas C; Ester, Edward F; Serences, John T

    2014-09-22

    Working memory (WM) enables the maintenance and manipulation of information relevant to behavioral goals. Variability in WM ability is strongly correlated with IQ [1], and WM function is impaired in many neurological and psychiatric disorders [2, 3], suggesting that this system is a core component of higher cognition. WM storage is thought to be mediated by patterns of activity in neural populations selective for specific properties (e.g., color, orientation, location, and motion direction) of memoranda [4-13]. Accordingly, many models propose that differences in the amplitude of these population responses should be related to differences in memory performance [14, 15]. Here, we used functional magnetic resonance imaging and an image reconstruction technique based on a spatial encoding model [16] to visualize and quantify population-level memory representations supported by multivoxel patterns of activation within regions of occipital, parietal and frontal cortex while participants precisely remembered the location(s) of zero, one, or two small stimuli. We successfully reconstructed images containing representations of the remembered-but not forgotten-locations within regions of occipital, parietal, and frontal cortex using delay-period activation patterns. Critically, the amplitude of representations of remembered locations and behavioral performance both decreased with increasing memory load. These results suggest that differences in visual WM performance between memory load conditions are mediated by changes in the fidelity of large-scale population response profiles distributed across multiple areas of human cortex. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Validation of 3D surface reconstruction of vertebrae and spinal column using 3D ultrasound data--a pilot study.

    Science.gov (United States)

    Nguyen, Duc V; Vo, Quang N; Le, Lawrence H; Lou, Edmond H M

    2015-02-01

    Adolescent idiopathic scoliosis (AIS) is a three-dimensional deformity of spine associated with vertebra rotation. The Cobb angle and axial vertebral rotation are important parameters to assess the severity of scoliosis. However, the vertebral rotation is seldom measured from radiographs due to time consuming. Different techniques have been developed to extract 3D spinal information. Among many techniques, ultrasound imaging is a promising method. This pilot study reported an image processing method to reconstruct the posterior surface of vertebrae from 3D ultrasound data. Three cadaver vertebrae, a Sawbones spine phantom, and a spine from a child with AIS were used to validate the development. The in-vitro result showed the surface of the reconstructed image was visually similar to the original objects. The dimension measurement error was 0.99. The results also showed a high accuracy in vertebral rotation with errors of 0.8 ± 0.3°, 2.8 ± 0.3° and 3.6 ± 0.5° for the rotation values of 0°, 15° and 30°, respectively. Meanwhile, the difference in the Cobb angle between the phantom and the image was 4° and the vertebral rotation at the apex was 2°. The Cobb angle measured from the in-vivo ultrasound image was 4° different from the radiograph. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  10. Visualization and 3D reconstruction of flame cells of Taenia solium (cestoda.

    Directory of Open Access Journals (Sweden)

    Laura E Valverde-Islas

    Full Text Available BACKGROUND: Flame cells are the terminal cells of protonephridial systems, which are part of the excretory systems of invertebrates. Although the knowledge of their biological role is incomplete, there is a consensus that these cells perform excretion/secretion activities. It has been suggested that the flame cells participate in the maintenance of the osmotic environment that the cestodes require to live inside their hosts. In live Platyhelminthes, by light microscopy, the cells appear beating their flames rapidly and, at the ultrastructural, the cells have a large body enclosing a tuft of cilia. Few studies have been performed to define the localization of the cytoskeletal proteins of these cells, and it is unclear how these proteins are involved in cell function. METHODOLOGY/PRINCIPAL FINDINGS: Parasites of two different developmental stages of T. solium were used: cysticerci recovered from naturally infected pigs and intestinal adults obtained from immunosuppressed and experimentally infected golden hamsters. Hamsters were fed viable cysticerci to recover adult parasites after one month of infection. In the present studies focusing on flame cells of cysticerci tissues was performed. Using several methods such as video, confocal and electron microscopy, in addition to computational analysis for reconstruction and modeling, we have provided a 3D visual rendition of the cytoskeletal architecture of Taenia solium flame cells. CONCLUSIONS/SIGNIFICANCE: We consider that visual representations of cells open a new way for understanding the role of these cells in the excretory systems of Platyhelminths. After reconstruction, the observation of high resolution 3D images allowed for virtual observation of the interior composition of cells. A combination of microscopic images, computational reconstructions and 3D modeling of cells appears to be useful for inferring the cellular dynamics of the flame cell cytoskeleton.

  11. Visualization and 3D Reconstruction of Flame Cells of Taenia solium (Cestoda)

    Science.gov (United States)

    Valverde-Islas, Laura E.; Arrangoiz, Esteban; Vega, Elio; Robert, Lilia; Villanueva, Rafael; Reynoso-Ducoing, Olivia; Willms, Kaethe; Zepeda-Rodríguez, Armando; Fortoul, Teresa I.; Ambrosio, Javier R.

    2011-01-01

    Background Flame cells are the terminal cells of protonephridial systems, which are part of the excretory systems of invertebrates. Although the knowledge of their biological role is incomplete, there is a consensus that these cells perform excretion/secretion activities. It has been suggested that the flame cells participate in the maintenance of the osmotic environment that the cestodes require to live inside their hosts. In live Platyhelminthes, by light microscopy, the cells appear beating their flames rapidly and, at the ultrastructural, the cells have a large body enclosing a tuft of cilia. Few studies have been performed to define the localization of the cytoskeletal proteins of these cells, and it is unclear how these proteins are involved in cell function. Methodology/Principal Findings Parasites of two different developmental stages of T. solium were used: cysticerci recovered from naturally infected pigs and intestinal adults obtained from immunosuppressed and experimentally infected golden hamsters. Hamsters were fed viable cysticerci to recover adult parasites after one month of infection. In the present studies focusing on flame cells of cysticerci tissues was performed. Using several methods such as video, confocal and electron microscopy, in addition to computational analysis for reconstruction and modeling, we have provided a 3D visual rendition of the cytoskeletal architecture of Taenia solium flame cells. Conclusions/Significance We consider that visual representations of cells open a new way for understanding the role of these cells in the excretory systems of Platyhelminths. After reconstruction, the observation of high resolution 3D images allowed for virtual observation of the interior composition of cells. A combination of microscopic images, computational reconstructions and 3D modeling of cells appears to be useful for inferring the cellular dynamics of the flame cell cytoskeleton. PMID:21412407

  12. The Subjective Visual Vertical: Validation of a Simple Test

    Science.gov (United States)

    Tesio, Luigi; Longo, Stefano; Rota, Viviana

    2011-01-01

    The study sought to provide norms for a simple test of visual perception of verticality (subjective visual vertical). The study was designed as a cohort study with a balanced design. The setting was the Rehabilitation Department of a University Hospital. Twenty-two healthy adults, of 23-58 years, 11 men (three left handed) and 11 women (three left…

  13. In vivo validation of reconstruction-based resolution recovery for human brain studies

    Science.gov (United States)

    Mourik, Jurgen EM; Lubberink, Mark; van Velden, Floris HP; Kloet, Reina W; van Berckel, Bart NM; Lammertsma, Adriaan A; Boellaard, Ronald

    2010-01-01

    The aim of this study was to validate in vivo the accuracy of a reconstruction-based partial volume correction (PVC), which takes into account the point spread function of the imaging system. The NEMA NU2 Image Quality phantom and five healthy volunteers (using [11C]flumazenil) were scanned on both HR+ and high-resolution research tomograph (HRRT) scanners. HR+ data were reconstructed using normalization and attenuation-weighted ordered subsets expectation maximization (NAW-OSEM) and a PVC algorithm (PVC-NAW-OSEM). HRRT data were reconstructed using 3D ordinary Poisson OSEM (OP-OSEM) and a PVC algorithm (PVC-OP-OSEM). For clinical studies, parametric volume of distribution (VT) images were generated. For phantom data, good recovery was found for both OP-OSEM (0.84 to 0.97) and PVC-OP-OSEM (0.91 to 0.98) HRRT reconstructions. In addition, for the HR+, good recovery was found for PVC-NAW-OSEM (0.84 to 0.94), corresponding well with OP-OSEM. Finally, for clinical data, good correspondence was found between PVC-NAW-OSEM and OP-OSEM-derived VT values (slope: 1.02±0.08). This study showed that HR+ image resolution using PVC-NAW-OSEM was comparable to that of the HRRT scanner. As the HRRT has a higher intrinsic resolution, this agreement validates reconstruction-based PVC as a means of improving the spatial resolution of the HR+ scanner and thereby improving the quantitative accuracy of positron emission tomography. PMID:19844240

  14. Validation of the visual analog scale in the cervical spine.

    Science.gov (United States)

    MacDowall, Anna; Skeppholm, Martin; Robinson, Yohan; Olerud, Claes

    2017-12-15

    OBJECTIVE The visual analog scale (VAS) is frequently used to measure treatment outcome in patients with cervical spine disorders. The minimum clinically important difference (MCID) is the smallest change in a score that has clinical importance to the patient. Although it has been established for other medical fields, knowledge of the VAS MCID for the cervical spine is sparse, and it has rarely been considered in relation to measurement noise. The goals in this study were as follows: 1) to validate the VAS-neck and VAS-arm instruments for the cervical spine (e.g., repeatability); 2) to investigate the possible influence of predictive factors and the Hospital Anxiety and Depression Scale (HADS) score on repeatability; and 3) to compute the MCID with 5 different methods. METHODS A post hoc analysis of a prospective randomized controlled trial with 151 patients undergoing surgery for cervical radiculopathy due to degenerative disc disease was performed. Information on age, sex, smoking habits, exercise, employment status, HADS score, and VAS-neck and VAS-arm scores was gathered before surgery and after 1 year. The VAS was applied twice on every occasion, with 15 minutes in between. Repeatability and the association with predictors and HADS score were analyzed using the 1-sample t-test, linear regression models, and Spearman correlation. The MCID was calculated with the following methods: average change, change difference, receiver operating characteristic curve, effect size, and minimum detectable change (MDC). RESULTS The repeatability in VAS-neck was 8.1 mm, and in VAS-arm it was 10.4 mm. Less consistent values on the VAS correlated to female sex and higher values on the HADS. For VAS-neck the MCID ranged from 4.6 to 21.4, and for VAS-arm it ranged from 1.1 to 29.1. The highest MCID came from the MDC method, which was the only method that gave values above the measurement noise in both VAS-neck and VAS-arm. CONCLUSIONS Measurement noise in VAS-neck and VAS-arm for

  15. Validation of simultaneous reverse optimization reconstruction algorithm in a practical circular subaperture stitching interferometer

    Science.gov (United States)

    Zhang, Lei; Li, Dong; Liu, Yu; Liu, Jingxiao; Li, Jingsong; Yu, Benli

    2017-11-01

    We demonstrate the validity of the simultaneous reverse optimization reconstruction (SROR) algorithm in circular subaperture stitching interferometry (CSSI), which is previously proposed for non-null aspheric annular subaperture stitching interferometry (ASSI). The merits of the modified SROR algorithm in CSSI, such as auto retrace error correction, no need of overlap and even permission of missed coverage, are analyzed in detail in simulations and experiments. Meanwhile, a practical CSSI system is proposed for this demonstration. An optical wedge is employed to deflect the incident beam for subaperture scanning by its rotation and shift instead of the six-axis motion-control system. Also the reference path can provide variable Zernike defocus for each subaperture test, which would decrease the fringe density. Experiments validating the SROR algorithm in this CSSI is implemented with cross validation by testing of paraboloidal mirror, flat mirror and astigmatism mirror. It is an indispensable supplement in SROR application in general subaperture stitching interferometry.

  16. GPS tomography: validation of reconstructed 3-D humidity fields with radiosonde profiles

    Directory of Open Access Journals (Sweden)

    M. Shangguan

    2013-09-01

    Full Text Available Water vapor plays an important role in meteorological applications; GeoForschungsZentrum (GFZ therefore developed a tomographic system to derive 3-D distributions of the tropospheric water vapor above Germany using GPS data from about 300 ground stations. Input data for the tomographic reconstructions are generated by the Earth Parameter and Orbit determination System (EPOS software of the GFZ, which provides zenith total delay (ZTD, integrated water vapor (IWV and slant total delay (STD data operationally with a temporal resolution of 2.5 min (STD and 15 min (ZTD, IWV. The water vapor distribution in the atmosphere is derived by tomographic reconstruction techniques. The quality of the solution is dependent on many factors such as the spatial coverage of the atmosphere with slant paths, the spatial distribution of their intersections and the accuracy of the input observations. Independent observations are required to validate the tomographic reconstructions and to get precise information on the accuracy of the derived 3-D water vapor fields. To determine the quality of the GPS tomography, more than 8000 vertical water vapor profiles at 13 German radiosonde stations were used for the comparison. The radiosondes were launched twice a day (at 00:00 UTC and 12:00 UTC in 2007. In this paper, parameters of the entire profiles such as the wet refractivity, and the zenith wet delay have been compared. Before the validation the temporal and spatial distribution of the slant paths, serving as a basis for tomographic reconstruction, as well as their angular distribution were studied. The mean wet refractivity differences between tomography and radiosonde data for all points vary from −1.3 to 0.3, and the root mean square is within the range of 6.5–9. About 32% of 6803 profiles match well, 23% match badly and 45% are difficult to classify as they match only in parts.

  17. GPS tomography. Validation of reconstructed 3-D humidity fields with radiosonde profiles

    Energy Technology Data Exchange (ETDEWEB)

    Shangguan, M.; Bender, M.; Ramatschi, M.; Dick, G.; Wickert, J. [Helmholtz Centre Potsdam, German Research Centre for Geosciences (GFZ), Potsdam (Germany); Raabe, A. [Leipzig Institute for Meteorology (LIM), Leipzig (Germany); Galas, R. [Technische Univ. Berlin (Germany). Dept. for Geodesy and Geoinformation Sciences

    2013-11-01

    Water vapor plays an important role in meteorological applications; GeoForschungsZentrum (GFZ) therefore developed a tomographic system to derive 3-D distributions of the tropospheric water vapor above Germany using GPS data from about 300 ground stations. Input data for the tomographic reconstructions are generated by the Earth Parameter and Orbit determination System (EPOS) software of the GFZ, which provides zenith total delay (ZTD), integrated water vapor (IWV) and slant total delay (STD) data operationally with a temporal resolution of 2.5 min (STD) and 15 min (ZTD, IWV). The water vapor distribution in the atmosphere is derived by tomographic reconstruction techniques. The quality of the solution is dependent on many factors such as the spatial coverage of the atmosphere with slant paths, the spatial distribution of their intersections and the accuracy of the input observations. Independent observations are required to validate the tomographic reconstructions and to get precise information on the accuracy of the derived 3-D water vapor fields. To determine the quality of the GPS tomography, more than 8000 vertical water vapor profiles at 13 German radiosonde stations were used for the comparison. The radiosondes were launched twice a day (at 00:00 UTC and 12:00 UTC) in 2007. In this paper, parameters of the entire profiles such as the wet refractivity, and the zenith wet delay have been compared. Before the validation the temporal and spatial distribution of the slant paths, serving as a basis for tomographic reconstruction, as well as their angular distribution were studied. The mean wet refractivity differences between tomography and radiosonde data for all points vary from -1.3 to 0.3, and the root mean square is within the range of 6.5-9. About 32% of 6803 profiles match well, 23% match badly and 45% are difficult to classify as they match only in parts.

  18. DIC image reconstruction using an energy minimization framework to visualize optical path length distribution.

    Science.gov (United States)

    Koos, Krisztian; Molnár, József; Kelemen, Lóránd; Tamás, Gábor; Horvath, Peter

    2016-07-25

    Label-free microscopy techniques have numerous advantages such as low phototoxicity, simple setup and no need for fluorophores or other contrast materials. Despite their advantages, most label-free techniques cannot visualize specific cellular compartments or the location of proteins and the image formation limits quantitative evaluation. Differential interference contrast (DIC) is a qualitative microscopy technique that shows the optical path length differences within a specimen. We propose a variational framework for DIC image reconstruction. The proposed method largely outperforms state-of-the-art methods on synthetic, artificial and real tests and turns DIC microscopy into an automated high-content imaging tool. Image sets and the source code of the examined algorithms are made publicly available.

  19. A new Gujarati language logMAR visual acuity chart: Development and validation

    OpenAIRE

    Ananth Sailoganathan; John Siderov; Ebi Osuobeni

    2013-01-01

    Aims: Gujarati is the main spoken language of a large proportion of the population of India. The aim of this study was to develop and validate a new Minimum Angle of Resolution (logMAR) visual acuity chart in the Gujarati language. Materials and Methods: A new Gujarati visual acuity chart was designed to logMAR specifications using Gujarati optotypes experimentally selected to have similar relative letter legibility under spherical and cylindrical defocus. The chart validation study was carri...

  20. Vivaldi: visualization and validation of biomacromolecular NMR structures from the PDB.

    Science.gov (United States)

    Hendrickx, Pieter M S; Gutmanas, Aleksandras; Kleywegt, Gerard J

    2013-04-01

    We describe Vivaldi (VIsualization and VALidation DIsplay; http://pdbe.org/vivaldi), a web-based service for the analysis, visualization, and validation of NMR structures in the Protein Data Bank (PDB). Vivaldi provides access to model coordinates and several types of experimental NMR data using interactive visualization tools, augmented with structural annotations and model-validation information. The service presents information about the modeled NMR ensemble, validation of experimental chemical shifts, residual dipolar couplings, distance and dihedral angle constraints, as well as validation scores based on empirical knowledge and databases. Vivaldi was designed for both expert NMR spectroscopists and casual non-expert users who wish to obtain a better grasp of the information content and quality of NMR structures in the public archive. Copyright © 2013 Wiley Periodicals, Inc.

  1. Activist Literacies: Validating Aboriginality through Visual and Literary Identity Texts

    Science.gov (United States)

    Montero, M. Kristiina; Bice-Zaugg, Cassandra; Marsh, Makwa Oshkwenh-Adam Cyril John; Cummins, Jim

    2013-01-01

    Framed at the intersection of activist and Indigenous research methodologies, this article explores the way two First Nations senior high school students made sense of their visual and literary identity texts (Cummins & Early, 2011). An Ojibwe artist-in-residence at an urban secondary school in southwestern Ontario and a university-based…

  2. Validation of the Preverbal Visual Assessment (PreViAs) questionnaire.

    Science.gov (United States)

    García-Ormaechea, Inés; González, Inmaculada; Duplá, María; Andres, Eva; Pueyo, Victoria

    2014-10-01

    Visual cognitive integrative functions need to be evaluated by a behavioral assessment, which requires an experienced evaluator. The Preverbal Visual Assessment (PreViAs) questionnaire was designed to evaluate these functions, both in general pediatric population or in children with high risk of visual cognitive problems, through primary caregivers' answers. We aimed to validate the PreViAs questionnaire by comparing caregiver reports with results from a comprehensive clinical protocol. A total of 220 infants (visual development, as determined by the clinical protocol. Their primary caregivers completed the PreViAs questionnaire, which consists of 30 questions related to one or more visual domains: visual attention, visual communication, visual-motor coordination, and visual processing. Questionnaire answers were compared with results of behavioral assessments performed by three pediatric ophthalmologists. Results of the clinical protocol classified 128 infants as having normal visual maturation, and 92 as having abnormal visual maturation. The specificity of PreViAs questionnaire was >80%, and sensitivity was 64%-79%. More than 80% of the infants were correctly classified, and test-retest reliability exceeded 0.9 for all domains. The PreViAs questionnaire is useful to detect abnormal visual maturation in infants from birth to 24months of age. It improves the anamnesis process in infants at risk of visual dysfunctions. Copyright © 2014. Published by Elsevier Ireland Ltd.

  3. Three-dimensional reconstruction of tumor microvasculature: simultaneous visualization of multiple components in paraffin-embedded tissue.

    Science.gov (United States)

    Gijtenbeek, J M M; Wesseling, P; Maass, C; Burgers, L; van der Laak, J A W M

    2005-01-01

    Three-dimensional (3D) visualization of microscopic structures may provide useful information about the exact 3D configuration, and offers a useful tool to examine the spatial relationship between different components in tissues. A promising field for 3D investigation is the microvascular architecture in normal and pathological tissue, especially because pathological angiogenesis plays a key role in tumor growth and metastasis formation. This paper describes an improved method for 3D reconstruction of microvessels and other microscopic structures in transmitted light microscopy. Serial tissue sections were stained for the endothelial marker CD34 to highlight microvessels and corresponding images were selected and aligned. Alignment of stored images was further improved by automated non-rigid image registration, and automated segmentation of microvessels was performed. Using this technique, 3D reconstructions were produced of the vasculature of the normal brain. Also, to illustrate the complexity of tumor vasculature, 3D reconstructions of two brain tumors were performed: a hemangioblastoma and a glioblastoma multiforme. The possibility of multiple component visualization was shown in a 3D reconstruction of endothelium and pericytes of normal cerebellar cortex and a hemangioblastoma using alternate staining for CD34 and alpha-smooth muscle actin in serial sections, and of a GBM using immunohistochemical double staining. In conclusion, the described 3D reconstruction procedure provides a promising tool for simultaneous visualization of microscopic structures.

  4. Comprehensive reconstruction and visualization of non-coding regulatory networks in human.

    Science.gov (United States)

    Bonnici, Vincenzo; Russo, Francesco; Bombieri, Nicola; Pulvirenti, Alfredo; Giugno, Rosalba

    2014-01-01

    Research attention has been powered to understand the functional roles of non-coding RNAs (ncRNAs). Many studies have demonstrated their deregulation in cancer and other human disorders. ncRNAs are also present in extracellular human body fluids such as serum and plasma, giving them a great potential as non-invasive biomarkers. However, non-coding RNAs have been relatively recently discovered and a comprehensive database including all of them is still missing. Reconstructing and visualizing the network of ncRNAs interactions are important steps to understand their regulatory mechanism in complex systems. This work presents ncRNA-DB, a NoSQL database that integrates ncRNAs data interactions from a large number of well established on-line repositories. The interactions involve RNA, DNA, proteins, and diseases. ncRNA-DB is available at http://ncrnadb.scienze.univr.it/ncrnadb/. It is equipped with three interfaces: web based, command-line, and a Cytoscape app called ncINetView. By accessing only one resource, users can search for ncRNAs and their interactions, build a network annotated with all known ncRNAs and associated diseases, and use all visual and mining features available in Cytoscape.

  5. Comprehensive Reconstruction and Visualization of Non-Coding Regulatory Networks in Human

    Science.gov (United States)

    Bonnici, Vincenzo; Russo, Francesco; Bombieri, Nicola; Pulvirenti, Alfredo; Giugno, Rosalba

    2014-01-01

    Research attention has been powered to understand the functional roles of non-coding RNAs (ncRNAs). Many studies have demonstrated their deregulation in cancer and other human disorders. ncRNAs are also present in extracellular human body fluids such as serum and plasma, giving them a great potential as non-invasive biomarkers. However, non-coding RNAs have been relatively recently discovered and a comprehensive database including all of them is still missing. Reconstructing and visualizing the network of ncRNAs interactions are important steps to understand their regulatory mechanism in complex systems. This work presents ncRNA-DB, a NoSQL database that integrates ncRNAs data interactions from a large number of well established on-line repositories. The interactions involve RNA, DNA, proteins, and diseases. ncRNA-DB is available at http://ncrnadb.scienze.univr.it/ncrnadb/. It is equipped with three interfaces: web based, command-line, and a Cytoscape app called ncINetView. By accessing only one resource, users can search for ncRNAs and their interactions, build a network annotated with all known ncRNAs and associated diseases, and use all visual and mining features available in Cytoscape. PMID:25540777

  6. Signal Reconstruction of the Atlas Hadronic Tile Calorimeter Implementation and Validation

    CERN Document Server

    Usai, G

    2010-01-01

    TileCal, the central hadronic section of the ATLAS Calorimeter, is a sampling calorimeter consisting of steel and scitntillating tiles. The TileCal front-end electronics allows to measures the signals produced by about 10000 photo-multipliers measuring energies ranging from about 30 MeV to about 2TeV .  The read-out system is responsible to reconstruct the data in real-time fulfilling the tight time constraint imposed by the ATLAS first level trigger rate (100 KHz).  The main component of the read-out system is the Digital Signal Processor (DSP) which, using the Optimal Filtering technique, allows to compute for each channel the signal amplitude, time and quality factor at the required high rate. After a short overview of the TileCal system we will discuss the implementation of Optimal Filtering signal reconstruction highlighting the constraints imposed by the use of the DSP. We will than report results on the validation of the implementation of the DSP signal reconstruction and the overall signal reconstru...

  7. Reliability and validity of the visual analogue scale for disability in patients with chronic musculoskeletal pain

    NARCIS (Netherlands)

    Boonstra, Anne M.; Schiphorst Preuper, Henrica R.; Reneman, Michiel F.; Posthumus, Jitze B.; Stewart, Roy E.

    To determine the reliability and concurrent validity of a visual analogue scale (VAS) for disability as a single-item instrument measuring disability in chronic pain patients was the objective of the study. For the reliability study a test-retest design and for the validity study a cross-sectional

  8. A Visual Culture Art Education Curriculum for Early Childhood Teacher Education: Re-Constructing the Family Album

    Science.gov (United States)

    Trafi, Laura

    2008-01-01

    This article reflects on the reading and writing of an art education curriculum for teacher education centred on the biographical and social reconstruction of childhood. The foundations of this curriculum interconnect ideas from different fields like postmodern childhood studies, visual studies, and the performance of subjectivity and memory. This…

  9. Experimental validation of a Bayesian model of visual acuity.

    LENUS (Irish Health Repository)

    Dalimier, Eugénie

    2009-01-01

    Based on standard procedures used in optometry clinics, we compare measurements of visual acuity for 10 subjects (11 eyes tested) in the presence of natural ocular aberrations and different degrees of induced defocus, with the predictions given by a Bayesian model customized with aberrometric data of the eye. The absolute predictions of the model, without any adjustment, show good agreement with the experimental data, in terms of correlation and absolute error. The efficiency of the model is discussed in comparison with image quality metrics and other customized visual process models. An analysis of the importance and customization of each stage of the model is also given; it stresses the potential high predictive power from precise modeling of ocular and neural transfer functions.

  10. Validation and Analysis of the Parameters for Reconstructing the Austenite Phase from Martensite Electron Backscatter Diffraction Data

    Science.gov (United States)

    Sanz, L.; Pereda, B.; López, B.

    2017-11-01

    This work focuses on the validation of a method for reconstructing the fcc crystallographic data from martensite orientation electron backscatter diffraction (EBSD) maps based on the " γ nuclei identification" and " γ nuclei spreading strategy." To that end, an Fe-30Ni alloy was employed. The martensite transformation start temperature ( M s ) of this material is close to or below room temperature; therefore, during hot deformation and after water quenching, it presents an fcc austenitic microstructure, while after subzero quenching, austenite-to-martensite transformation takes place. Accordingly, the reconstruction procedure can be applied to the martensitic EBSD crystallographic data, and the morphological and orientation results of the reconstruction can be validated by comparison with the original crystallographic fcc data. Torsion tests were performed to produce recrystallized and deformed austenite microstructures. Although applying the Kurdjumov-Sachs orientation relationship (OR) resulted in reconstructed area fractions larger than 75 pct, the reconstruction quality improved significantly when other ORs closer to the Greninger-Troiano OR were applied. The analysis carried out on the recrystallized microstructure shows that the method is robust against variation in the different parameters involved in the reconstruction. Good angular and morphological reconstruction results were obtained in both recrystallized and deformed microstructures, including the ability to reconstruct twins.

  11. D Reconstruction and Visualization of Cultural Heritage: Analyzing Our Legacy Through Time

    Science.gov (United States)

    Rodríguez-Gonzálvez, P.; Muñoz-Nieto, A. L.; del Pozo, S.; Sanchez-Aparicio, L. J.; Gonzalez-Aguilera, D.; Micoli, L.; Gonizzi Barsanti, S.; Guidi, G.; Mills, J.; Fieber, K.; Haynes, I.; Hejmanowska, B.

    2017-02-01

    Temporal analyses and multi-temporal 3D reconstruction are fundamental for the preservation and maintenance of all forms of Cultural Heritage (CH) and are the basis for decisions related to interventions and promotion. Introducing the fourth dimension of time into three-dimensional geometric modelling of real data allows the creation of a multi-temporal representation of a site. In this way, scholars from various disciplines (surveyors, geologists, archaeologists, architects, philologists, etc.) are provided with a new set of tools and working methods to support the study of the evolution of heritage sites, both to develop hypotheses about the past and to model likely future developments. The capacity to "see" the dynamic evolution of CH assets across different spatial scales (e.g. building, site, city or territory) compressed in diachronic model, affords the possibility to better understand the present status of CH according to its history. However, there are numerous challenges in order to carry out 4D modelling and the requisite multi-data source integration. It is necessary to identify the specifications, needs and requirements of the CH community to understand the required levels of 4D model information. In this way, it is possible to determine the optimum material and technologies to be utilised at different CH scales, as well as the data management and visualization requirements. This manuscript aims to provide a comprehensive approach for CH time-varying representations, analysis and visualization across different working scales and environments: rural landscape, urban landscape and architectural scales. Within this aim, the different available metric data sources are systemized and evaluated in terms of their suitability.

  12. 3D image stack reconstruction in live cell microscopy of Drosophila muscles and its validation.

    Science.gov (United States)

    Du, Tiehua; Wasser, Martin

    2009-04-01

    Rapid movements of live tissues during the acquisition of 3D image stacks can result in misalignments between successive image slices. The remodeling of the muscles in Drosophila metamorphosis is an example where sporadic motion during image acquisition impede image analysis and volume visualization. Most of the image stack registration algorithms applied in microscopy are aimed at the linear alignment of fixed histological sections. However, live muscles are nonrigid objects and their contractions and relaxations represent nonlinear transformations that cannot be properly rectified by applying purely linear registration methods. We developed a fully automated area-based nonrigid stack registration (NSR) method that minimizes the mean square error of intensities between successive image slices. The mapping function is formulated using the thin plate spline (TPS). A hierarchical linear to nonlinear, coarse to fine matching strategy is applied to ensure stability and fast convergence. Topological structure is preserved by constraining the step size of the nonlinear transformation. To assess the accuracy of 3D reconstruction, we propose a new benchmarking method that measures geometrical features of restored nuclei. We tested our algorithm on image stacks generated by laser scanning confocal microscopy that show live muscles during the prepupal stage of Drosophila metamorphosis. Our registration algorithm is able to restore image stacks that are distorted by periodic contraction of muscles. Quantitative assessment of registration performance agrees well with qualitative visual inspection. Our NSR method is able to restore image stacks for the purpose of visualization and quantitative analysis of Drosophila metamorphosis and, potentially, various other processes in developmental biology studied by 3D live cell microscopy. (c) 2009 International Society for Advancement of Cytometry.

  13. Validation and Reliability of Visual Assessment with a Shade Guide for Tooth-Color Classification.

    OpenAIRE

    Meireles, Sônia Saeger; Demarco, Flávio Fernando; Santos,Iná da Silva dos; Dumith, Samuel Carvalho; Bona, Álvaro Della

    2008-01-01

    This study evaluated the validity and reliability of the visual assessment of tooth color using a commercial shade guide. Ninety-two individuals were randomly selected from subjects enrolled in a randomized controlled trial comparing two formulations of carbamide peroxide. Initially, each individual had the color of his or her six maxillary anterior teeth (n=552) determined by one examiner using a digital spectrophotometer (Vita Easyshade). Then, a visual assessment was made by two calibrated...

  14. The Grief and Meaning Reconstruction Inventory (GMRI): Initial Validation of a New Measure.

    Science.gov (United States)

    Gillies, James M; Neimeyer, Robert A; Milman, Evgenia

    2015-01-01

    Although increasing numbers of grief theorists, researchers, and therapists have begun to focus on the quest for meaning in lives disrupted by loss, no convenient and psychometrically validated measure of meanings made specifically in bereavement has been available to guide their efforts. To construct such a measure, the authors began with a systematic content analysis of sense-making, benefit finding, and identity reconstruction themes gleaned from the narrative responses of a sample of 162 adults who were diverse in their age, ethnicity, relationship to the decedent, cause of death, and severity of their grief response. These were then formulated into a set of 65 candidate items in a Likert scale format representing the level of the respondent's endorsement of the item in the past week. Subsequent administration to a second sample of 300 bereaved respondents permitted factor analysis of this pilot version of the Grief and Meaning Reconstruction Inventory (GMRI), and reduced the items to 29, which loaded on 5 distinct factors, labeled Continuing Bonds, Personal Growth, Sense of Peace, Emptiness and Meaninglessness, and Valuing Life. Both the overall GMRI and its constituent factors showed good internal consistency and strong convergent validity in the form of negative correlations with established measures of bereavement-related negative emotions, symptoms of complicated grief, and more general psychological distress and mental health symptomatology, and positive correlations with grief related personal growth. The authors close by noting several specific research and clinical applications of the measure, which could play a useful role in testing and refining contemporary models of meaning made in the wake of loss.

  15. Can DMCO Detect Visual Field Loss in Neurological Patients? A Secondary Validation Study

    DEFF Research Database (Denmark)

    Olsen, Ane Sophie; Steensberg, Alvilda Thougaard; la Cour, Morten

    2017-01-01

    Unrecognized visual field loss is caused by a range of blinding eye conditions as well as serious brain diseases. The commonest cause of asymptomatic visual field loss is glaucoma. No screening tools have been proven cost-effective. Damato Multifixation Campimetry Online (DMCO), an inexpensive...... online test, has been evaluated as a future cost-beneficial tool to detect glaucoma. To further validate DMCO, this study aimed to test DMCO in a preselected population with neurological visual field loss. Methods : The study design was an evaluation of a diagnostic test. Patients were included...

  16. "Visually clean" as a sole acceptance criterion for cleaning validation protocols.

    Science.gov (United States)

    LeBlanc, Destin A

    2002-01-01

    The role of visual examination as the sole acceptance criterion in cleaning validation protocols is explored, including the proper definition of "visual limit" for a given residue. Such a visual limit is specific to the surface the residue is on, and is further defined by viewing conditions, such as lighting, distance, and angle of viewing. A visually clean standard may only be properly utilized if the visual limit is below any scientifically calculated residue limit, such as that determined by a traditional dose-based limit determination. While such an approach, properly applied, has scientific justification and appears to be accepted by the proposed Annex 15 to the European GMPs, the approach is still untested with regulatory authorities.

  17. [Research on Three-dimensional Medical Image Reconstruction and Interaction Based on HTML5 and Visualization Toolkit].

    Science.gov (United States)

    Gao, Peng; Liu, Peng; Su, Hongsen; Qiao, Liang

    2015-04-01

    Integrating visualization toolkit and the capability of interaction, bidirectional communication and graphics rendering which provided by HTML5, we explored and experimented on the feasibility of remote medical image reconstruction and interaction in pure Web. We prompted server-centric method which did not need to download the big medical data to local connections and avoided considering network transmission pressure and the three-dimensional (3D) rendering capability of client hardware. The method integrated remote medical image reconstruction and interaction into Web seamlessly, which was applicable to lower-end computers and mobile devices. Finally, we tested this method in the Internet and achieved real-time effects. This Web-based 3D reconstruction and interaction method, which crosses over internet terminals and performance limited devices, may be useful for remote medical assistant.

  18. The validation of the visual analogue scale for patient satisfaction after total hip arthroplasty

    OpenAIRE

    Brokelman, Roy B. G.; Haverkamp, Daniel; van Loon, Corné; Hol, Annemiek; van Kampen, Albert; Veth, Rene

    2012-01-01

    Introduction Patient satisfaction becomes more important in our modern health care system. The assessment of satisfaction is difficult because it is a multifactorial item for which no golden standard exists. One of the potential methods of measuring satisfaction is by using the well-known visual analogue scale (VAS). In this study, we validated VAS for satisfaction. Patient and methods In this prospective study, we studied 147 patients (153 hips). The construct validity was measured using the...

  19. Reconstructive endovascular treatment of vertebral artery dissecting aneurysms with the Low-profile Visualized Intraluminal Support (LVIS) device

    OpenAIRE

    Wang, Chuan-Chuan; Fang, Yi-Bin; Zhang, Ping; ZHU, XUAN; Hong, Bo; Xu, Yi; Liu, Jian-Min; Huang, Qing-Hai

    2017-01-01

    Introduction The Low-profile Visualized Intraluminal Support (LVIS) device is a new generation of self-expanding braided stent recently introduced in China for stent assisted coiling of intracranial aneurysms. The aim of our study is to evaluate the feasibility, safety, and efficacy of the LVIS device in reconstructive treatment of vertebral artery dissecting aneurysms (VADAs). Methods We retrospectively reviewed the neurointerventional database of our institution from June 2014 to May 2016. ...

  20. Validity of the rey visual design test in primary and secondary school children

    NARCIS (Netherlands)

    Wilhelm, P.; van Klink, M.; van Klink, M.

    2007-01-01

    The Rey Visual Design Learning Test (Rey, 1964, cited in Spreen & Strauss, 1991, Wilhelm, 2004) assesses immediate memory span, new learning, delayed recall and recognition for nonverbal material. Two studies are presented that focused on the construct validity of the RVDLT in primary and secondary

  1. Reliability and validity of the rey visual design learning test in primary school children

    NARCIS (Netherlands)

    Wilhelm, P.

    2004-01-01

    The Rey Visual Design Learning Test (Rey, 1964, in Spreen & Strauss, 1991) assesses immediate memory span, new learning and recognition for non-verbal material. Three studies are presented that focused on the reliability and validity of the RVDLT in primary school children. Test-retest reliability

  2. A Rasch-Based Validation of the Hooper Visual Organization Test in Chinese-Speaking Children

    Science.gov (United States)

    Wuang, Yee-Pay; Wang, Li-Chen; Su, Chwen-Yng

    2010-01-01

    The aim of this study was to examine the validation of the Hooper Visual Organization Test (HVOT) for use in children by testing for item fit, unidimensionality, item hierarchy, reliability, and screening capacity. A modified scoring system was devised for the HVOT so that children received some credit for being able to describe the function of…

  3. Reliability and Validity of Generalizable Skills Instruments for Students Who Are Deaf, Blind, or Visually Impaired.

    Science.gov (United States)

    Loeding, Barbara L.; Greenan, James P.

    1998-01-01

    This study examined the validity and reliability of four assessments, with three instruments per domain, with 103 students at residential secondary schools for the hearing or visually impaired. Domains included generalizable mathematics, communication, interpersonal relations, and reasoning skills. Data suggest the instruments are highly…

  4. Validation and reconstruction of FY-3B/MWRI soil moisture using an artificial neural network based on reconstructed MODIS optical products over the Tibetan Plateau

    Science.gov (United States)

    Cui, Yaokui; Long, Di; Hong, Yang; Zeng, Chao; Zhou, Jie; Han, Zhongying; Liu, Ronghua; Wan, Wei

    2016-12-01

    Soil moisture is a key variable in the exchange of water and energy between the land surface and the atmosphere, especially over the Tibetan Plateau (TP) which is climatically and hydrologically sensitive as the Earth's 'third pole'. Large-scale spatially consistent and temporally continuous soil moisture datasets are of great importance to meteorological and hydrological applications, such as weather forecasting and drought monitoring. The Fengyun-3B Microwave Radiation Imager (FY-3B/MWRI) soil moisture product is a relatively new passive microwave product, with the satellite being launched on November 5, 2010. This study validates and reconstructs FY-3B/MWRI soil moisture across the TP. First, the validation is performed using in situ measurements within two in situ soil moisture measurement networks (1° × 1° and 0.25° × 0.25°), and also compared with the Essential Climate Variable (ECV) soil moisture product from multiple active and passive satellite soil moisture products using new merging procedures. Results show that the ascending FY-3B/MWRI product outperforms the descending product. The ascending FY-3B/MWRI product has almost the same correlation as the ECV product with the in situ measurements. The ascending FY-3B/MWRI product has better performance than the ECV product in the frozen season and under the lower NDVI condition. When the NDVI is higher in the unfrozen season, uncertainty in the ascending FY-3B/MWRI product increases with increasing NDVI, but it could still capture the variability in soil moisture. Second, the FY-3B/MWRI soil moisture product is subsequently reconstructed using the back-propagation neural network (BP-NN) based on reconstructed MODIS products, i.e., LST, NDVI, and albedo. The reconstruction method of generating the soil moisture product not only considers the relationship between the soil moisture and NDVI, LST, and albedo, but also the relationship between the soil moisture and four-dimensional variations using the

  5. A new Gujarati language logMAR visual acuity chart: development and validation.

    Science.gov (United States)

    Sailoganathan, Ananth; Siderov, John; Osuobeni, Ebi

    2013-10-01

    Gujarati is the main spoken language of a large proportion of the population of India. The aim of this study was to develop and validate a new Minimum Angle of Resolution (logMAR) visual acuity chart in the Gujarati language. A new Gujarati visual acuity chart was designed to logMAR specifications using Gujarati optotypes experimentally selected to have similar relative letter legibility under spherical and cylindrical defocus. The chart validation study was carried out using 153 adult subjects in a large clinical setting in India. Subjects who were literate in English and Gujarati participated in the study. Visual acuity was measured with the new Gujarati logMAR chart and a modified Early Treatment of Diabetic Retinopathy Study-(m-ETDRS) logMAR chart. The method of presentation was randomized between the charts. Repeat visual acuity was measured on a subsequent day with a second version of the Gujarati logMAR chart. The Gujarati chart correlated highly with the m-ETDRS logMAR chart (r² = 0.974). The mean visual acuity difference (Gujarati - m-ETDRS logMAR) was equal to three letters (-0.06 logMAR). The Gujarati logMAR chart also proved to be highly repeatable (r² = 0.994, test-retest) with 95% CI of ± 0.04 logMAR. The new Gujarati logMAR visual acuity chart provides a valid and repeatable tool for the measurement of visual acuity in native Gujarati language speakers.

  6. A new Gujarati language logMAR visual acuity chart: Development and validation

    Directory of Open Access Journals (Sweden)

    Ananth Sailoganathan

    2013-01-01

    Full Text Available Aims: Gujarati is the main spoken language of a large proportion of the population of India. The aim of this study was to develop and validate a new Minimum Angle of Resolution (logMAR visual acuity chart in the Gujarati language. Materials and Methods: A new Gujarati visual acuity chart was designed to logMAR specifications using Gujarati optotypes experimentally selected to have similar relative letter legibility under spherical and cylindrical defocus. The chart validation study was carried out using 153 adult subjects in a large clinical setting in India. Subjects who were literate in English and Gujarati participated in the study. Visual acuity was measured with the new Gujarati logMAR chart and a modified Early Treatment of Diabetic Retinopathy Study-(m-ETDRS logMAR chart. The method of presentation was randomized between the charts. Repeat visual acuity was measured on a subsequent day with a second version of the Gujarati logMAR chart. Results: The Gujarati chart correlated highly with the m-ETDRS logMAR chart (r2 = 0.974. The mean visual acuity difference (Gujarati - m-ETDRS logMAR was equal to three letters (-0.06 logMAR. The Gujarati logMAR chart also proved to be highly repeatable (r2 = 0.994, test-retest with 95% CI of ± 0.04 logMAR. Conclusions: The new Gujarati logMAR visual acuity chart provides a valid and repeatable tool for the measurement of visual acuity in native Gujarati language speakers.

  7. Assistive technology for visually impaired women for use of the female condom: a validation study

    Directory of Open Access Journals (Sweden)

    Luana Duarte Wanderley Cavalcante

    2015-02-01

    Full Text Available OBJECTIVE To validate assistive technology for visually impaired women to learn how to use the female condom. METHOD a methodological development study conducted on a web page, with data collection between May and October 2012. Participants were 14 judges; seven judges in sexual and reproductive health (1st stage and seven in special education (2nd stage. RESULTS All items have reached the adopted parameter of 70% agreement. In Stage 1 new materials were added to represent the cervix, and instructions that must be heard twice were included in the 2nd stage. CONCLUSION The technology has been validated and is appropriate for its objectives, structure / presentation and relevance. It is an innovative, low cost and valid instrument for promoting health and one which may help women with visual disabilities to use the female condom.

  8. Initial Validation Study for a Scale Used to Determine Service Intensity for Itinerant Teachers of Students with Visual Impairments

    Science.gov (United States)

    Pogrund, Rona L.; Darst, Shannon; Munro, Michael P.

    2015-01-01

    Introduction: The purpose of this study was to begin validation of a scale that will be used by teachers of students with visual impairments to determine appropriate recommended type and frequency of services for their students based on identified student need. Methods: Validity and reliability of the Visual Impairment Scale of Service Intensity…

  9. A Visual Analysis Concept for the Validation of Geoscientific Simulation Models.

    Science.gov (United States)

    Unger, A; Schulte, S; Klemann, V; Dransch, D

    2012-12-01

    Geoscientific modeling and simulation helps to improve our understanding of the complex Earth system. During the modeling process, validation of the geoscientific model is an essential step. In validation, it is determined whether the model output shows sufficient agreement with observation data. Measures for this agreement are called goodness of fit. In the geosciences, analyzing the goodness of fit is challenging due to its manifold dependencies: 1) The goodness of fit depends on the model parameterization, whose precise values are not known. 2) The goodness of fit varies in space and time due to the spatio-temporal dimension of geoscientific models. 3) The significance of the goodness of fit is affected by resolution and preciseness of available observational data. 4) The correlation between goodness of fit and underlying modeled and observed values is ambiguous. In this paper, we introduce a visual analysis concept that targets these challenges in the validation of geoscientific models - specifically focusing on applications where observation data is sparse, unevenly distributed in space and time, and imprecise, which hinders a rigorous analytical approach. Our concept, developed in close cooperation with Earth system modelers, addresses the four challenges by four tailored visualization components. The tight linking of these components supports a twofold interactive drill-down in model parameter space and in the set of data samples, which facilitates the exploration of the numerous dependencies of the goodness of fit. We exemplify our visualization concept for geoscientific modeling of glacial isostatic adjustments in the last 100,000 years, validated against sea levels indicators - a prominent example for sparse and imprecise observation data. An initial use case and feedback from Earth system modelers indicate that our visualization concept is a valuable complement to the range of validation methods.

  10. Real-time SPARSE-SENSE cardiac cine MR imaging: optimization of image reconstruction and sequence validation.

    Science.gov (United States)

    Goebel, Juliane; Nensa, Felix; Bomas, Bettina; Schemuth, Haemi P; Maderwald, Stefan; Gratz, Marcel; Quick, Harald H; Schlosser, Thomas; Nassenstein, Kai

    2016-12-01

    Improved real-time cardiac magnetic resonance (CMR) sequences have currently been introduced, but so far only limited practical experience exists. This study aimed at image reconstruction optimization and clinical validation of a new highly accelerated real-time cine SPARSE-SENSE sequence. Left ventricular (LV) short-axis stacks of a real-time free-breathing SPARSE-SENSE sequence with high spatiotemporal resolution and of a standard segmented cine SSFP sequence were acquired at 1.5 T in 11 volunteers and 15 patients. To determine the optimal iterations, all volunteers' SPARSE-SENSE images were reconstructed using 10-200 iterations, and contrast ratios, image entropies, and reconstruction times were assessed. Subsequently, the patients' SPARSE-SENSE images were reconstructed with the clinically optimal iterations. LV volumetric values were evaluated and compared between both sequences. Sufficient image quality and acceptable reconstruction times were achieved when using 80 iterations. Bland-Altman plots and Passing-Bablok regression showed good agreement for all volumetric parameters. 80 iterations are recommended for iterative SPARSE-SENSE image reconstruction in clinical routine. Real-time cine SPARSE-SENSE yielded comparable volumetric results as the current standard SSFP sequence. Due to its intrinsic low image acquisition times, real-time cine SPARSE-SENSE imaging with iterative image reconstruction seems to be an attractive alternative for LV function analysis. • A highly accelerated real-time CMR sequence using SPARSE-SENSE was evaluated. • SPARSE-SENSE allows free breathing in real-time cardiac cine imaging. • For clinically optimal SPARSE-SENSE image reconstruction, 80 iterations are recommended. • Real-time SPARSE-SENSE imaging yielded comparable volumetric results as the reference SSFP sequence. • The fast SPARSE-SENSE sequence is an attractive alternative to standard SSFP sequences.

  11. Validity and reliability of self-assessed physical fitness using visual analogue scales

    DEFF Research Database (Denmark)

    Strøyer, Jesper; Essendrop, Morten; Jensen, Lone Donbaek

    2007-01-01

    To test the validity and reliability of self-assessed physical fitness samples included healthcare assistants working at a hospital (women=170, men=17), persons working with physically and mentally handicapped patients (women=530, men= 123), and two separate groups of healthcare students (a) women......=91 and men=5 and (b) women=159 and men=10. Five components of physical fitness were self-assessed by Visual Analogue Scales with illustrations and verbal anchors for the extremes: aerobic fitness, muscle strength, endurance, flexibility, and balance. Convergent and divergent validity were evaluated...... by age-adjusted correlations stratified by sex with performance-based measures of physical fitness. Self-assessed aerobic fitness (r = .36 - .64) (women/men), muscle strength (r = .30 - .51), and flexibility (r = .36 - .31) showed moderate convergent validity. The divergent validity was satisfactory...

  12. Bayesian three-dimensional reconstruction of toothed whale trajectories: passive acoustics assisted with visual and tagging measurements.

    Science.gov (United States)

    Laplanche, Christophe

    2012-11-01

    The author describes and evaluates a Bayesian method to reconstruct three-dimensional toothed whale trajectories from a series of echolocation signals. Localization by using passive acoustic data (time of arrival of source signals at receptors) is assisted by using visual data (coordinates of the whale when diving and resurfacing) and tag information (movement statistics). The efficiency of the Bayesian method is compared to the standard minimum mean squared error statistical approach by comparing the reconstruction results of 48 simulated sperm whale (Physeter macrocephalus) trajectories. The use of the advanced Bayesian method reduces bias (standard deviation) with respect to the standard method up to a factor of 8.9 (13.6). The author provides open-source software which is functional with acoustic data which would be collected in the field from any three-dimensional receptor array design. This approach renews passive acoustics as a valuable tool to study the underwater behavior of toothed whales.

  13. Visual biofeedback exercises for improving body balance control after anterior cruciate ligament reconstruction

    OpenAIRE

    Molka, Alicja Zyta; Lisi?ski, Przemys?aw; Huber, Juliusz

    2015-01-01

    [Purpose] To evaluate the effects of balance training after arthroscopic anterior cruciate ligament reconstruction. [Subjects and Methods] Sixteen patients (mean 33 ? 8?years old) who underwent anterior cruciate ligament reconstruction three months prior to participating in a one-month rehabilitation program. The control group included 15 people aged 34 ? 4?years. Patients? functional level was evaluated according to the Lysholm knee score, and balance quality was ascertained by static and dy...

  14. The Visual Analogue WOMAC 3.0 scale - internal validity and responsiveness of the VAS version

    OpenAIRE

    Tennant Alan; White Peter J; Kersten Paula

    2010-01-01

    Abstract Background Many people suffer with Osteoarthritis (OA) and subsequent morbidity. Therefore, measuring outcome associated with OA is important. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) has been a widely used patient reported outcome in OA. However, there is relatively little evidence to support the use of the Visual Analogue Scale (VAS) version of the scale. We aimed to explore the internal validity and responsiveness of this VAS version of the WOMAC....

  15. Quantitative regional validation of the visual rating scale for posterior cortical atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, Christiane; Benedictus, Marije R.; Koedam, Esther L.G.M.; Scheltens, Philip [VU University Medical Center, Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Flier, Wiesje M. van der [VU University Medical Center, Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); VU University Medical Center, Department of Epidemiology and Biostatistics, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Versteeg, Adriaan; Wattjes, Mike P.; Barkhof, Frederik [VU University Medical Center, Department of Radiology and Nuclear Medicine, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Vrenken, Hugo [VU University Medical Center, Department of Radiology and Nuclear Medicine, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); VU University Medical Center, Department of Physics and Medical Technology, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands)

    2014-02-15

    Validate the four-point visual rating scale for posterior cortical atrophy (PCA) on magnetic resonance images (MRI) through quantitative grey matter (GM) volumetry and voxel-based morphometry (VBM) to justify its use in clinical practice. Two hundred twenty-nine patients with probable Alzheimer's disease and 128 with subjective memory complaints underwent 3T MRI. PCA was rated according to the visual rating scale. GM volumes of six posterior structures and the total posterior region were extracted using IBASPM and compared among PCA groups. To determine which anatomical regions contributed most to the visual scores, we used binary logistic regression. VBM compared local GM density among groups. Patients were categorised according to their PCA scores: PCA-0 (n = 122), PCA-1 (n = 143), PCA-2 (n = 79), and PCA-3 (n = 13). All structures except the posterior cingulate differed significantly among groups. The inferior parietal gyrus volume discriminated the most between rating scale levels. VBM showed that PCA-1 had a lower GM volume than PCA-0 in the parietal region and other brain regions, whereas between PCA-1 and PCA-2/3 GM atrophy was mostly restricted to posterior regions. The visual PCA rating scale is quantitatively validated and reliably reflects GM atrophy in parietal regions, making it a valuable tool for the daily radiological assessment of dementia. (orig.)

  16. Validation of the Caprini Risk Assessment Model in Plastic and Reconstructive Surgery Patients

    Science.gov (United States)

    Pannucci, Christopher J.; Bailey, Steven H.; Dreszer, George; Fisher, Christine; Zumsteg, Justin W.; Jaber, Reda M.; Hamill, Jennifer B.; Hume, Keith M.; Rubin, J. Peter; Neligan, Peter C.; Kallianen, Loree K.; Hoxworth, Ronald E.; Pusic, Andrea L.; Wilkins, Edwin G.

    2010-01-01

    Background The VTEPS Network is a consortium of five tertiary referral centers established to examine venous thromboembolism in plastic surgery patients. We report our mid-term analyses of the study’s control group to 1) evaluate the incidence of VTE in patients who receive no chemoprophylaxis and 2) validate the Caprini Risk Assessment Model (RAM) in plastic surgery patients. Study Design Medical record review was performed at VTEPS centers for all eligible plastic surgery patients between March 2006 and June 2009. Inclusion criteria were Caprini score ≥ 3, surgery under general anesthesia, and post-operative hospital admission. Patients who received chemoprophylaxis were excluded. Dependent variables included symptomatic DVT or PE within the first 60 post-operative days and time to DVT or PE. Results We identified 1126 historic control patients. The overall VTE incidence was 1.69%. Approximately one in nine (11.3%) patients with Caprini score >8 had a VTE event. Patients with Caprini score >8 were significantly more likely to develop VTE when compared to patients with Caprini score of 3–4 (OR 20.9, p8, VTE risk was not limited to the immediate post-operative period. Conclusions The Caprini RAM effectively risk-stratifies plastic and reconstructive surgery patients for VTE risk. Among patients with Caprini score >8, 11.3% have a post-operative VTE when chemoprophylaxis is not provided. In higher risk patients, there was no evidence that VTE risk is limited to the immediate post-operative period. PMID:21093314

  17. Validity and reproducibility of cephalometric measurements performed in full and hemifacial reconstructions derived from cone beam computed tomography

    OpenAIRE

    Ramirez-Sotelo, LR; Almeida, S; Ambrosano, GM; F.; Boscolo

    2012-01-01

    Objective: To test the reproducibility and validity of angular measurements from virtual lateral cephalometric radiography (LCR) reconstructions (full and hemifacial on both sides) derived from cone beam computed tomography (CBCT). Materials and Methods: Fifty-eight CBCT and LCR images were selected. CBCT volume data were imported into Nemotec software, and virtual LCR images and tomographic slices from CBCT images were assessed. Three observers digitized landmarks used for 12 angular measure...

  18. Visual event-related potential studies supporting the validity of VARK learning styles' visual and read/write learners.

    Science.gov (United States)

    Thepsatitporn, Sarawin; Pichitpornchai, Chailerd

    2016-06-01

    The validity of learning styles needs supports of additional objective evidence. The identification of learning styles using subjective evidence from VARK questionnaires (where V is visual, A is auditory, R is read/write, and K is kinesthetic) combined with objective evidence from visual event-related potential (vERP) studies has never been investigated. It is questionable whether picture superiority effects exist in V learners and R learners. Thus, the present study aimed to investigate whether vERP could show the relationship between vERP components and VARK learning styles and to identify the existence of picture superiority effects in V learners and R learners. Thirty medical students (15 V learners and 15 R learners) performed recognition tasks with vERP and an intermediate-term memory (ITM) test. The results of within-group comparisons showed that pictures elicited larger P200 amplitudes than words at the occipital 2 site (P VARK questionnaire study. Copyright © 2016 The American Physiological Society.

  19. Visualization and Phospholipid Identification (VaLID): online integrated search engine capable of identifying and visualizing glycerophospholipids with given mass

    Science.gov (United States)

    Figeys, Daniel; Fai, Stephen; Bennett, Steffany A. L.

    2013-01-01

    Motivation: Establishing phospholipid identities in large lipidomic datasets is a labour-intensive process. Where genomics and proteomics capitalize on sequence-based signatures, glycerophospholipids lack easily definable molecular fingerprints. Carbon chain length, degree of unsaturation, linkage, and polar head group identity must be calculated from mass to charge (m/z) ratios under defined mass spectrometry (MS) conditions. Given increasing MS sensitivity, many m/z values are not represented in existing prediction engines. To address this need, Visualization and Phospholipid Identification is a web-based application that returns all theoretically possible phospholipids for any m/z value and MS condition. Visualization algorithms produce multiple chemical structure files for each species. Curated lipids detected by the Canadian Institutes of Health Research Training Program in Neurodegenerative Lipidomics are provided as high-resolution structures. Availability: VaLID is available through the Canadian Institutes of Health Research Training Program in Neurodegenerative Lipidomics resources web site at https://www.med.uottawa.ca/lipidomics/resources.html. Contacts: lipawrd@uottawa.ca Supplementary Information: Supplementary data are available at Bioinformatics online. PMID:23162086

  20. Developing Retina and PNS Segments for Transplantation Into the Adult Host Eye: Reconstruction of the Mammalian Visual System. 1. Methodology

    Science.gov (United States)

    Zanakis, Michael F.; Lowe, Howard F.; Jacobsen, Glenn; LaCorte, Michael; Lee, Simone P.; Hallas, Brian H.

    1989-01-01

    Various techniques have been explored to determine the uses and limitations of techniques that enable the adult CNS to regenerate, but relatively little attention has been given to the consideration of a "reconstructed" visual system. Using this approach, one can design experiments to study the uses of exogenous tissues in reestablishing neuronal circuits that have been damaged. Toward this end, experiments were designed to determine whether embryonic retinal ganglion cells can project axons into a grafted PNS "bridge", and enter adult host targets that were partially deafferented. Embryonic eyes of E11, E14, E18 and E21 rats were sutured to peripheral nerve segments which served as bridges between the host eye and frontal cortex. Projections between the developing retina and the host brain could then be evaluated using HRP tracing techniques. From a methodological standpoint, the preparations are 65% effective; i.e., a viable bridge results between the embryonic eye and the host forebrain. The results presented in the accompanying paper demonstrate that the technique can yield results indicative of embryonic retinal development and axonal projection through the graft and into the host brain. This partial reconstruction of the visual system may prove a useful tool in understanding the uses and limitations of grafting in the CNS. PMID:2485119

  1. Cue-induced craving among inhalant users: Development and preliminary validation of a visual cue paradigm.

    Science.gov (United States)

    Jain, Shobhit; Dhawan, Anju; Kumaran, S Senthil; Pattanayak, Raman Deep; Jain, Raka

    2017-12-01

    Cue-induced craving is known to be associated with a higher risk of relapse, wherein drug-specific cues become conditioned stimuli, eliciting conditioned responses. Cue-reactivity paradigm are important tools to study psychological responses and functional neuroimaging changes. However, till date, there has been no specific study or a validated paradigm for inhalant cue-induced craving research. The study aimed to develop and validate visual cue stimulus for inhalant cue-associated craving. The first step (picture selection) involved screening and careful selection of 30 cue- and 30 neutral-pictures based on their relevance for naturalistic settings. In the second step (time optimization), a random selection of ten cue-pictures each was presented for 4s, 6s, and 8s to seven adolescent male inhalant users, and pre-post craving response was compared using a Visual Analogue Scale(VAS) for each of the picture and time. In the third step (validation), craving response for each of 30 cue- and 30 neutral-pictures were analysed among 20 adolescent inhalant users. Findings revealed a significant difference in before and after craving response for the cue-pictures, but not neutral-pictures. Using ROC-curve, pictures were arranged in order of craving intensity. Finally, 20 best cue- and 20 neutral-pictures were used for the development of a 480s visual cue paradigm. This is the first study to systematically develop an inhalant cue picture paradigm which can be used as a tool to examine cue induced craving in neurobiological studies. Further research, including its further validation in larger study and diverse samples, is required. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Development and validation of a visual grading scale for assessing image quality of AP pelvis radiographic images

    Science.gov (United States)

    England, Andrew; Cassidy, Simon; Eachus, Peter; Dominguez, Alejandro; Hogg, Peter

    2016-01-01

    Objective: The aim of this article was to apply psychometric theory to develop and validate a visual grading scale for assessing the visual perception of digital image quality anteroposterior (AP) pelvis. Methods: Psychometric theory was used to guide scale development. Seven phantom and seven cadaver images of visually and objectively predetermined quality were used to help assess scale reliability and validity. 151 volunteers scored phantom images, and 184 volunteers scored cadaver images. Factor analysis and Cronbach's alpha were used to assess scale validity and reliability. Results: A 24-item scale was produced. Aggregated mean volunteer scores for each image correlated with the rank order of the visually and objectively predetermined image qualities. Scale items had good interitem correlation (≥0.2) and high factor loadings (≥0.3). Cronbach's alpha (reliability) revealed that the scale has acceptable levels of internal reliability for both phantom and cadaver images (α = 0.8 and 0.9, respectively). Factor analysis suggested that the scale is multidimensional (assessing multiple quality themes). Conclusion: This study represents the first full development and validation of a visual image quality scale using psychometric theory. It is likely that this scale will have clinical, training and research applications. Advances in knowledge: This article presents data to create and validate visual grading scales for radiographic examinations. The visual grading scale, for AP pelvis examinations, can act as a validated tool for future research, teaching and clinical evaluations of image quality. PMID:26943836

  3. 'tomo_display' and 'vol_tools': IDL VM Packages for Tomography Data Reconstruction, Processing, and Visualization

    Science.gov (United States)

    Rivers, M. L.; Gualda, G. A.

    2009-05-01

    One of the challenges in tomography is the availability of suitable software for image processing and analysis in 3D. We present here 'tomo_display' and 'vol_tools', two packages created in IDL that enable reconstruction, processing, and visualization of tomographic data. They complement in many ways the capabilities offered by Blob3D (Ketcham 2005 - Geosphere, 1: 32-41, DOI: 10.1130/GES00001.1) and, in combination, allow users without programming knowledge to perform all steps necessary to obtain qualitative and quantitative information using tomographic data. The package 'tomo_display' was created and is maintained by Mark Rivers. It allows the user to: (1) preprocess and reconstruct parallel beam tomographic data, including removal of anomalous pixels, ring artifact reduction, and automated determination of the rotation center, (2) visualization of both raw and reconstructed data, either as individual frames, or as a series of sequential frames. The package 'vol_tools' consists of a series of small programs created and maintained by Guilherme Gualda to perform specific tasks not included in other packages. Existing modules include simple tools for cropping volumes, generating histograms of intensity, sample volume measurement (useful for porous samples like pumice), and computation of volume differences (for differential absorption tomography). The module 'vol_animate' can be used to generate 3D animations using rendered isosurfaces around objects. Both packages use the same NetCDF format '.volume' files created using code written by Mark Rivers. Currently, only 16-bit integer volumes are created and read by the packages, but floating point and 8-bit data can easily be stored in the NetCDF format as well. A simple GUI to convert sequences of tiffs into '.volume' files is available within 'vol_tools'. Both 'tomo_display' and 'vol_tools' include options to (1) generate onscreen output that allows for dynamic visualization in 3D, (2) save sequences of tiffs to disk

  4. Influence of Ultra-Low-Dose and Iterative Reconstructions on the Visualization of Orbital Soft Tissues on Maxillofacial CT.

    Science.gov (United States)

    Widmann, G; Juranek, D; Waldenberger, F; Schullian, P; Dennhardt, A; Hoermann, R; Steurer, M; Gassner, E-M; Puelacher, W

    2017-08-01

    Dose reduction on CT scans for surgical planning and postoperative evaluation of midface and orbital fractures is an important concern. The purpose of this study was to evaluate the variability of various low-dose and iterative reconstruction techniques on the visualization of orbital soft tissues. Contrast-to-noise ratios of the optic nerve and inferior rectus muscle and subjective scores of a human cadaver were calculated from CT with a reference dose protocol (CT dose index volume = 36.69 mGy) and a subsequent series of low-dose protocols (LDPs I-4: CT dose index volume = 4.18, 2.64, 0.99, and 0.53 mGy) with filtered back-projection (FBP) and adaptive statistical iterative reconstruction (ASIR)-50, ASIR-100, and model-based iterative reconstruction. The Dunn Multiple Comparison Test was used to compare each combination of protocols (α = .05). Compared with the reference dose protocol with FBP, the following statistically significant differences in contrast-to-noise ratios were shown (all, P ≤ .012) for the following: 1) optic nerve: LDP-I with FBP; LDP-II with FBP and ASIR-50; LDP-III with FBP, ASIR-50, and ASIR-100; and LDP-IV with FBP, ASIR-50, and ASIR-100; and 2) inferior rectus muscle: LDP-II with FBP, LDP-III with FBP and ASIR-50, and LDP-IV with FBP, ASIR-50, and ASIR-100. Model-based iterative reconstruction showed the best contrast-to-noise ratio in all images and provided similar subjective scores for LDP-II. ASIR-50 had no remarkable effect, and ASIR-100, a small effect on subjective scores. Compared with a reference dose protocol with FBP, model-based iterative reconstruction may show similar diagnostic visibility of orbital soft tissues at a CT dose index volume of 2.64 mGy. Low-dose technology and iterative reconstruction technology may redefine current reference dose levels in maxillofacial CT. © 2017 by American Journal of Neuroradiology.

  5. Post-processing methods of rendering and visualizing 3-D reconstructed tomographic images

    Energy Technology Data Exchange (ETDEWEB)

    Wong, S.T.C. [Univ. of California, San Francisco, CA (United States)

    1997-02-01

    The purpose of this presentation is to discuss the computer processing techniques of tomographic images, after they have been generated by imaging scanners, for volume visualization. Volume visualization is concerned with the representation, manipulation, and rendering of volumetric data. Since the first digital images were produced from computed tomography (CT) scanners in the mid 1970s, applications of visualization in medicine have expanded dramatically. Today, three-dimensional (3D) medical visualization has expanded from using CT data, the first inherently digital source of 3D medical data, to using data from various medical imaging modalities, including magnetic resonance scanners, positron emission scanners, digital ultrasound, electronic and confocal microscopy, and other medical imaging modalities. We have advanced from rendering anatomy to aid diagnosis and visualize complex anatomic structures to planning and assisting surgery and radiation treatment. New, more accurate and cost-effective procedures for clinical services and biomedical research have become possible by integrating computer graphics technology with medical images. This trend is particularly noticeable in current market-driven health care environment. For example, interventional imaging, image-guided surgery, and stereotactic and visualization techniques are now stemming into surgical practice. In this presentation, we discuss only computer-display-based approaches of volumetric medical visualization. That is, we assume that the display device available is two-dimensional (2D) in nature and all analysis of multidimensional image data is to be carried out via the 2D screen of the device. There are technologies such as holography and virtual reality that do provide a {open_quotes}true 3D screen{close_quotes}. To confine the scope, this presentation will not discuss such approaches.

  6. VIRTUAL RECONSTRUCTION OF LOST ARCHITECTURES: FROM THE TLS SURVEY TO AR VISUALIZATION

    Directory of Open Access Journals (Sweden)

    R. Quattrini

    2016-06-01

    Full Text Available The exploitation of high quality 3D models for dissemination of archaeological heritage is currently an investigated topic, although Mobile Augmented Reality platforms for historical architecture are not available, allowing to develop low-cost pipelines for effective contents. The paper presents a virtual anastylosis, starting from historical sources and from 3D model based on TLS survey. Several efforts and outputs in augmented or immersive environments, exploiting this reconstruction, are discussed. The work demonstrates the feasibility of a 3D reconstruction approach for complex architectural shapes starting from point clouds and its AR/VR exploitation, allowing the superimposition with archaeological evidences. Major contributions consist in the presentation and the discussion of a pipeline starting from the virtual model, to its simplification showing several outcomes, comparing also the supported data qualities and advantages/disadvantages due to MAR and VR limitations.

  7. Visual biofeedback exercises for improving body balance control after anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Molka, Alicja Zyta; Lisiński, Przemysław; Huber, Juliusz

    2015-07-01

    [Purpose] To evaluate the effects of balance training after arthroscopic anterior cruciate ligament reconstruction. [Subjects and Methods] Sixteen patients (mean 33 ± 8 years old) who underwent anterior cruciate ligament reconstruction three months prior to participating in a one-month rehabilitation program. The control group included 15 people aged 34 ± 4 years. Patients' functional level was evaluated according to the Lysholm knee score, and balance quality was ascertained by static and dynamic tests. A balance platform was used to measure the center of foot pressure deflection. Two dynamic balance tests evaluated time of task execution. [Results] Lysholm knee score improved significantly after rehabilitation. Balance in the sagittal plane with eyes closed improved significantly after rehabilitation. The average velocity of center of foot pressure swing in both the frontal and sagittal planes with eyes closed differed significantly from those of controls. Execution time required for the two dynamic tests decreased significantly after rehabilitation and were significantly better than those in the controls. [Conclusion] Maintaining static balance with eyes closed is very challenging after anterior cruciate ligament reconstruction. Maintaining balance in the sagittal plane is particularly difficult. A one-month rehabilitation program partially improves static and dynamic balance.

  8. The footprints of visual attention during search with 100% valid and 100% invalid cues.

    Science.gov (United States)

    Eckstein, Miguel P; Pham, Binh T; Shimozaki, Steven S

    2004-06-01

    Human performance during visual search typically improves when spatial cues indicate the possible target locations. In many instances, the performance improvement is quantitatively predicted by a Bayesian or quasi-Bayesian observer in which visual attention simply selects the information at the cued locations without changing the quality of processing or sensitivity and ignores the information at the uncued locations. Aside from the general good agreement between the effect of the cue on model and human performance, there has been little independent confirmation that humans are effectively selecting the relevant information. In this study, we used the classification image technique to assess the effectiveness of spatial cues in the attentional selection of relevant locations and suppression of irrelevant locations indicated by spatial cues. Observers searched for a bright target among dimmer distractors that might appear (with 50% probability) in one of eight locations in visual white noise. The possible target location was indicated using a 100% valid box cue or seven 100% invalid box cues in which the only potential target locations was uncued. For both conditions, we found statistically significant perceptual templates shaped as differences of Gaussians at the relevant locations with no perceptual templates at the irrelevant locations. We did not find statistical significant differences between the shapes of the inferred perceptual templates for the 100% valid and 100% invalid cues conditions. The results confirm the idea that during search visual attention allows the observer to effectively select relevant information and ignore irrelevant information. The results for the 100% invalid cues condition suggests that the selection process is not drawn automatically to the cue but can be under the observers' voluntary control.

  9. Is visual estimation of passive range of motion in the pediatric lower limb valid and reliable

    Directory of Open Access Journals (Sweden)

    Dagher Fernand

    2009-10-01

    Full Text Available Abstract Background Visual estimation (VE is an essential tool for evaluation of range of motion. Few papers discussed its validity in children orthopedics' practice. The purpose of our study was to assess validity and reliability of VE for passive range of motions (PROMs of children's lower limbs. Methods Fifty typically developing children (100 lower limbs were examined. Visual estimations for PROMs of hip (flexion, adduction, abduction, internal and external rotations, knee (flexion and popliteal angle and ankle (dorsiflexion and plantarflexion were made by a pediatric orthopaedic surgeon (POS and a 5th year resident in orthopaedics. A last year medical student did goniometric measurements. Three weeks later, same measurements were performed to assess reliability of visual estimation for each examiner. Results Visual estimations of the POS were highly reliable for hip flexion, hip rotations and popliteal angle (ρc ≥ 0.8. Reliability was good for hip abduction, knee flexion, ankle dorsiflexion and plantarflexion (ρc ≥ 0.7 but poor for hip adduction (ρc = 0.5. Reproducibility for all PROMs was verified. Resident's VE showed high reliability (ρc ≥ 0.8 for hip flexion and popliteal angle. Good correlation was found for hip rotations and knee flexion (ρc ≥ 0.7. Poor results were obtained for ankle PROMs (ρc Conclusion Accuracy of VE of passive hip flexion and knee PROMs is high regardless of the examiner's experience. Same accuracy can be found for hip rotations and abduction whenever VE is performed by an experienced examiner. Goniometric evaluation is recommended for passive hip adduction and for ankle PROMs.

  10. Visual Tools for Crowdsourcing Data Validation Within the GLOBELAND30 Geoportal

    Science.gov (United States)

    Chuprikova, E.; Wu, H.; Murphy, C. E.; Meng, L.

    2016-06-01

    This research aims to investigate the role of visualization of the user generated data that can empower the geoportal of GlobeLand30 produced by NGCC (National Geomatics Center of China). The focus is set on the development of a concept of tools that can extend the Geo-tagging functionality and make use of it for different target groups. The anticipated tools should improve the continuous data validation, updating and efficient use of the remotely-sensed data distributed within GlobeLand30.

  11. Validation of PSF-based 3D reconstruction for myocardial blood flow measurements with Rb-82 PET

    DEFF Research Database (Denmark)

    Tolbod, Lars Poulsen; Christensen, Nana Louise; Møller, Lone W.

    Aim:The use of PSF-based 3D reconstruction algorithms (PSF) is desirable in most clinical PET-exams due to their superior image quality. Rb-82 cardiac PET is inherently noisy due to short half-life and prompt gammas and would presumably benefit from PSF. However, the quantitative behavior of PSF...... is not well validated and problems with both edge-effects and unphysical contrast-recovery have been reported.1 In this study, we compare myocardial blood flow (MBF) and coronary flow reserve (CFR) obtained using GEs implementation of PSF, SharpIR, with the conventional method for reconstruction of dynamic...... images, filtered backprojection (FBP). Furthermore, since myocardial segmentation might be affected by image quality, two different approaches to segmentation implemented in standard software (Carimas (Turku PET Centre) and QPET (Cedar Sinai)) are utilized. Method:14 dynamic rest-stress Rb-82 patient...

  12. Hardware Implementation and Validation of 3D Underwater Shape Reconstruction Algorithm Using a Stereo-Catadioptric System

    Directory of Open Access Journals (Sweden)

    Rihab Hmida

    2016-08-01

    Full Text Available In this paper, we present a new stereo vision-based system and its efficient hardware implementation for real-time underwater environments exploration throughout 3D sparse reconstruction based on a number of feature points. The proposed underwater 3D shape reconstruction algorithm details are presented. The main concepts and advantages are discussed and comparison with existing systems is performed. In order to achieve real-time video constraints, a hardware implementation of the algorithm is performed using Xilinx System Generator. The pipelined stereo vision system has been implemented using Field Programmable Gate Arrays (FPGA technology. Both timing constraints and mathematical operations precision have been evaluated in order to validate the proposed hardware implementation of our system. Experimental results show that the proposed system presents high accuracy and execution time performances.

  13. A cross-validated cytoarchitectonic atlas of the human ventral visual stream.

    Science.gov (United States)

    Rosenke, Mona; Weiner, Kevin S; Barnett, Michael A; Zilles, Karl; Amunts, Katrin; Goebel, Rainer; Grill-Spector, Kalanit

    2017-02-16

    The human ventral visual stream consists of several areas that are considered processing stages essential for perception and recognition. A fundamental microanatomical feature differentiating areas is cytoarchitecture, which refers to the distribution, size, and density of cells across cortical layers. Because cytoarchitectonic structure is measured in 20-micron-thick histological slices of postmortem tissue, it is difficult to assess (a) how anatomically consistent these areas are across brains and (b) how they relate to brain parcellations obtained with prevalent neuroimaging methods, acquired at the millimeter and centimeter scale. Therefore, the goal of this study was to (a) generate a cross-validated cytoarchitectonic atlas of the human ventral visual stream on a whole brain template that is commonly used in neuroimaging studies and (b) to compare this atlas to a recently published retinotopic parcellation of visual cortex (Wang et al., 2014). To achieve this goal, we generated an atlas of eight cytoarchitectonic areas: four areas in the occipital lobe (hOc1-hOc4v) and four in the fusiform gyrus (FG1-FG4), then we tested how the different alignment techniques affect the accuracy of the resulting atlas. Results show that both cortex-based alignment (CBA) and nonlinear volumetric alignment (NVA) generate an atlas with better cross-validation performance than affine volumetric alignment (AVA). Additionally, CBA outperformed NVA in 6/8 of the cytoarchitectonic areas. Finally, the comparison of the cytoarchitectonic atlas to a retinotopic atlas shows a clear correspondence between cytoarchitectonic and retinotopic areas in the ventral visual stream. The successful performance of CBA suggests a coupling between cytoarchitectonic areas and macroanatomical landmarks in the human ventral visual stream, and furthermore, that this coupling can be utilized for generating an accurate group atlas. In addition, the coupling between cytoarchitecture and retinotopy highlights

  14. Data Visualization and Analysis Tools for the Global Precipitation Measurement (GPM) Validation Network

    Science.gov (United States)

    Morris, Kenneth R.; Schwaller, Mathew

    2010-01-01

    The Validation Network (VN) prototype for the Global Precipitation Measurement (GPM) Mission compares data from the Tropical Rainfall Measuring Mission (TRMM) satellite Precipitation Radar (PR) to similar measurements from U.S. and international operational weather radars. This prototype is a major component of the GPM Ground Validation System (GVS). The VN provides a means for the precipitation measurement community to identify and resolve significant discrepancies between the ground radar (GR) observations and similar satellite observations. The VN prototype is based on research results and computer code described by Anagnostou et al. (2001), Bolen and Chandrasekar (2000), and Liao et al. (2001), and has previously been described by Morris, et al. (2007). Morris and Schwaller (2009) describe the PR-GR volume-matching algorithm used to create the VN match-up data set used for the comparisons. This paper describes software tools that have been developed for visualization and statistical analysis of the original and volume matched PR and GR data.

  15. Reliability, validity and sensitivity of a computerized visual analog scale measuring state anxiety.

    Science.gov (United States)

    Abend, Rany; Dan, Orrie; Maoz, Keren; Raz, Sivan; Bar-Haim, Yair

    2014-12-01

    Assessment of state anxiety is frequently required in clinical and research settings, but its measurement using standard multi-item inventories entails practical challenges. Such inventories are increasingly complemented by paper-and-pencil, single-item visual analog scales measuring state anxiety (VAS-A), which allow rapid assessment of current anxiety states. Computerized versions of VAS-A offer additional advantages, including facilitated and accurate data collection and analysis, and applicability to computer-based protocols. Here, we establish the psychometric properties of a computerized VAS-A. Experiment 1 assessed the reliability, convergent validity, and discriminant validity of the computerized VAS-A in a non-selected sample. Experiment 2 assessed its sensitivity to increase in state anxiety following social stress induction, in participants with high levels of social anxiety. Experiment 1 demonstrated the computerized VAS-A's test-retest reliability (r = .44, p validity with the State-Trait Anxiety Inventory's state subscale (STAI-State; r = .60, p validity as indicated by significantly lower correlations between VAS-A and different psychological measures relative to the correlation between VAS-A and STAI-State. Experiment 2 demonstrated the VAS-A's sensitivity to changes in state anxiety via a significant pre- to during-stressor rise in VAS-A scores (F(1,48) = 25.13, p VAS-A a valuable self-rating tool for state anxiety. It may prove particularly useful for clinical and research settings where multi-item inventories are less applicable, including computer-based treatment and assessment protocols. The VAS-A is freely available: http://people.socsci.tau.ac.il/mu/anxietytrauma/visual-analog-scale/. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Reliability and validity of the visual analogue scale for disability in patients with chronic musculoskeletal pain.

    Science.gov (United States)

    Boonstra, Anne M; Schiphorst Preuper, Henrica R; Reneman, Michiel F; Posthumus, Jitze B; Stewart, Roy E

    2008-06-01

    To determine the reliability and concurrent validity of a visual analogue scale (VAS) for disability as a single-item instrument measuring disability in chronic pain patients was the objective of the study. For the reliability study a test-retest design and for the validity study a cross-sectional design was used. A general rehabilitation centre and a university rehabilitation centre was the setting for the study. The study population consisted of patients over 18 years of age, suffering from chronic musculoskeletal pain; 52 patients in the reliability study, 344 patients in the validity study. Main outcome measures were as follows. Reliability study: Spearman's correlation coefficients (rho values) of the test and retest data of the VAS for disability; validity study: rho values of the VAS disability scores with the scores on four domains of the Short-Form Health Survey (SF-36) and VAS pain scores, and with Roland-Morris Disability Questionnaire scores in chronic low back pain patients. Results were as follows: in the reliability study rho values varied from 0.60 to 0.77; and in the validity study rho values of VAS disability scores with SF-36 domain scores varied from 0.16 to 0.51, with Roland-Morris Disability Questionnaire scores from 0.38 to 0.43 and with VAS pain scores from 0.76 to 0.84. The conclusion of the study was that the reliability of the VAS for disability is moderate to good. Because of a weak correlation with other disability instruments and a strong correlation with the VAS for pain, however, its validity is questionable.

  17. Palmyra as it Once Was: 3d Virtual Reconstruction and Visualization of AN Irreplacable Lost Treasure

    Science.gov (United States)

    Denker, A.

    2017-05-01

    Palmyra was a mosaic which was composed through its colourful past, by Assyrians, Parthians, Greeks and Romans. For centuries, the spectacular ruins and impressive panorama of the antique city used to captivate and inspire the visitors as the witnesses of its illustrious history. As a grim consequence of the horrific conflict that engulfed Syria, since May 2015 they are no more to be seen. Palmyra has been purposely targeted and obliterated, the ruins have been reduced to rubble. The immense beauty and rich heritage of Palmyra which has been lost forever is reconstructed here as it was once was, at the top of its glory, with the hope of preserving its memory.

  18. Automated quality assessment of structural magnetic resonance images in children: Comparison with visual inspection and surface-based reconstruction.

    Science.gov (United States)

    White, Tonya; Jansen, Philip R; Muetzel, Ryan L; Sudre, Gustavo; El Marroun, Hanan; Tiemeier, Henning; Qiu, Anqi; Shaw, Philip; Michael, Andrew M; Verhulst, Frank C

    2017-12-05

    Motion-related artifacts are one of the major challenges associated with pediatric neuroimaging. Recent studies have shown a relationship between visual quality ratings of T1 images and cortical reconstruction measures. Automated algorithms offer more precision in quantifying movement-related artifacts compared to visual inspection. Thus, the goal of this study was to test three different automated quality assessment algorithms for structural MRI scans. The three algorithms included a Fourier-, integral-, and a gradient-based approach which were run on raw T1 -weighted imaging data collected from four different scanners. The four cohorts included a total of 6,662 MRI scans from two waves of the Generation R Study, the NIH NHGRI Study, and the GUSTO Study. Using receiver operating characteristics with visually inspected quality ratings of the T1 images, the area under the curve (AUC) for the gradient algorithm, which performed better than either the integral or Fourier approaches, was 0.95, 0.88, and 0.82 for the Generation R, NHGRI, and GUSTO studies, respectively. For scans of poor initial quality, repeating the scan often resulted in a better quality second image. Finally, we found that even minor differences in automated quality measurements were associated with FreeSurfer derived measures of cortical thickness and surface area, even in scans that were rated as good quality. Our findings suggest that the inclusion of automated quality assessment measures can augment visual inspection and may find use as a covariate in analyses or to identify thresholds to exclude poor quality data. © 2017 Wiley Periodicals, Inc.

  19. Validation of the MASK-rhinitis visual analogue scale on smartphone screens to assess allergic rhinitis control

    NARCIS (Netherlands)

    Caimmi, D.; Baiz, N.; Tanno, L. K.; Demoly, P.; Arnavielhe, S.; Murray, R.; Bedbrook, A.; Bergmann, K. C.; de Vries, G.; Fokkens, W. J.; Fonseca, J.; Haahtela, T.; Keil, T.; Kuna, P.; Mullol, J.; Papadopoulos, N.; Passalacqua, G.; Samolinski, B.; Tomazic, P. V.; Valiulis, A.; van Eerd, M.; Wickman, M.; Annesi-Maesano, I.; Bousquet, J.; Agache, I.; Angles, R.; Anto, J. M.; Asayag, E.; Bacci, E.; Bachert, C.; Baroni, I.; Barreto, B. A.; Bedolla-Barajas, M.; Bertorello, L.; Bewick, M.; Bieber, T.; Birov, S.; Bindslev-Jensen, C.; Blua, A.; Bochenska Marciniak, M.; Bogus-Buczynska, I.; Bosnic-Ancevich, S.; Bosse, I.; Bourret, R.; Bucca, C.; Buonaiuto, R.; Caiazza, D.; Caillot, D.; Caimmi, D. P.; Camargos, P.; Canfora, G.; Cardona, V.; Carriazo, A. M.; Cartier, C.; Castellano, G.; Chavannes, N. H.; Ciaravolo, M. M.; Cingi, C.; Ciceran, A.; Colas, L.; Colgan, E.; Coll, J.; Conforti, D.; Correira de Sousa, J.; Cortés-Grimaldo, R. M.; Corti, F.; Costa, E.; Courbis, A. L.; Cruz, A.; Custovic, A.; Dario, C.; da Silva, M.; Dauvilliers, Y.; de Blay, F.; Dedeu, T.; de Feo, G.; de Martino, B.; Di Capua, S.; Di Carluccio, N.; Dray, G.; Dubakiene, R.; Eller, E.; Emuzyte, R.; Espinoza-Contreras, J. M.; Estrada-Cardona, A.; Farrell, J.; Ferrero, J.; Fontaine, J. F.; Forti, S.; Gálvez-Romero, J. L.; Garcia Cruz, M. H.; García-Cobas, C. I.; Gemicioğlu, B.; Gerth van Wijck, R.; Guidacci, M.; Gómez-Vera, J.; Guldemond, N. A.; Gutter, Z.; Hajjam, J.; Hellings, P.; Hernández-Velázquez, L.; Illario, M.; Ivancevich, J. C.; Jares, E.; Joos, G.; Just, J.; Kalayci, O.; Kalyoncu, A. F.; Karjalainen, J.; Khaltaev, N.; Klimek, L.; Kull, I.; Kuna, T. P.; Kvedariene, V.; Kolek, V.; Krzych-Fałta, E.; Kupczyk, M.; Lacwik, P.; Larenas-Linnemann, D.; Laune, D.; Lauri, D.; Lavrut, J.; Lessa, M.; Levato, G.; Lewis, L.; Lieten, I.; Lipiec, A.; Louis, R.; Luna-Pech, J. A.; Magnan, A.; Malva, J.; Maspero, J. F.; Mayora, O.; Medina-Ávalos, M. A.; Melen, E.; Menditto, E.; Millot-Keurinck, J.; Moda, G.; Morais-Almeida, M.; Mösges, R.; Mota-Pinto, A.; Muraro, A.; Noguès, M.; Nalin, M.; Napoli, L.; Neffen, H.; O'Hehir, R.; Olivé Elias, M.; Onorato, G.; Palkonen, S.; Pépin, J. L.; Pereira, A. M.; Persico, M.; Pfaar, O.; Pozzi, A. C.; Prokopakis, E. P.; Raciborski, F.; Rizzo, J. A.; Robalo-Cordeiro, C.; Rodríguez-González, M.; Rolla, G.; Roller-Wirnsberger, R. E.; Romano, A.; Romano, M.; Salimäki, J.; Serpa, F. S.; Shamai, S.; Sierra, M.; Sova, M.; Sorlini, M.; Stellato, C.; Stelmach, R.; Strandberg, T.; Stroetman, V.; Stukas, R.; Szylling, A.; Tibaldi, V.; Todo-Bom, A.; Toppila-Salmi, S.; Tomazic, P.; Trama, U.; Triggiani, M.; Valero, A.; Valovirta, E.; Vasankari, T.; Vatrella, A.; Ventura, M. T.; Verissimo, M. T.; Viart, F.; Williams, S.; Wagenmann, M.; Wanscher, C.; Westman, M.; Young, I.; Yorgancioglu, A.; Zernotti, E.; Zurbierber, T.; Zurkuhlen, A.; de Oliviera, B.; Senn, A.

    2017-01-01

    Background: Visual Analogue Scale (VAS) is a validated tool to assess control in allergic rhinitis patients. Objective: The aim of this study was to validate the use of VAS in the MASK-rhinitis (MACVIA-ARIA Sentinel NetworK for allergic rhinitis) app (Allergy Diary) on smartphones screens to

  20. RECONSTRUCTION, QUANTIFICATION, AND VISUALIZATION OF FOREST CANOPY BASED ON 3D TRIANGULATIONS OF AIRBORNE LASER SCANNING POINT DATA

    Directory of Open Access Journals (Sweden)

    J. Vauhkonen

    2015-03-01

    Full Text Available Reconstruction of three-dimensional (3D forest canopy is described and quantified using airborne laser scanning (ALS data with densities of 0.6–0.8 points m-2 and field measurements aggregated at resolutions of 400–900 m2. The reconstruction was based on computational geometry, topological connectivity, and numerical optimization. More precisely, triangulations and their filtrations, i.e. ordered sets of simplices belonging to the triangulations, based on the point data were analyzed. Triangulating the ALS point data corresponds to subdividing the underlying space of the points into weighted simplicial complexes with weights quantifying the (empty space delimited by the points. Reconstructing the canopy volume populated by biomass will thus likely require filtering to exclude that volume from canopy voids. The approaches applied for this purpose were (i to optimize the degree of filtration with respect to the field measurements, and (ii to predict this degree by means of analyzing the persistent homology of the obtained triangulations, which is applied for the first time for vegetation point clouds. When derived from optimized filtrations, the total tetrahedral volume had a high degree of determination (R2 with the stem volume considered, both alone (R2=0.65 and together with other predictors (R2=0.78. When derived by analyzing the topological persistence of the point data and without any field input, the R2 were lower, but the predictions still showed a correlation with the field-measured stem volumes. Finally, producing realistic visualizations of a forested landscape using the persistent homology approach is demonstrated.

  1. The three-dimensional reconstruction and visualization of direct intrahepatic portacaval shunt

    Directory of Open Access Journals (Sweden)

    Hao Du

    2016-01-01

    Full Text Available Objective: Transjugular intrahepatic portacaval shunt (TIPS is a traditional and effective treatment for variceal bleeding in cirrhotic patients with portal hypertension. However, in patients with a Budd-Chiari syndrome or other unaccessible hepatic veins, a direct puncture through the inferior caval vein may be inevitable. Direct intrahepatic portacaval shunt (DIPS also has several advantages compared with TIPS. So we are expected to explore a digitalized model of DIPS and find the suitable shunt pathway of DIPS. Materials and Methods: We chose four hundred serial sectional images from the internal jugular vein superior margin to the edge interior hepatic from Chinese Visible Human Dataset. Surface and volume reconstruction were performed by 3D Doctor 3.5 software programs(ABLE SOFTWARE. Results: We reconstructed a digitalized model including liver and relevant vessels. It can display distribution characteristics and spatial structure relationship of intrahepatic vessels from any positions and angles. Conclusion: DIPS represents a useful addition to the endovascular techniques for managing complications of portal hypertension. The model of DIPS provides a good 3D morphological reference of image diagnostics and interventional therapy for DIPS.

  2. DIC image reconstruction using an energy minimization framework to visualize optical path length distribution

    OpenAIRE

    Krisztian Koos; József Molnár; Lóránd Kelemen; Gábor Tamás; Peter Horvath

    2016-01-01

    Label-free microscopy techniques have numerous advantages such as low phototoxicity, simple setup and no need for fluorophores or other contrast materials. Despite their advantages, most label-free techniques cannot visualize specific cellular compartments or the location of proteins and the image formation limits quantitative evaluation. Differential interference contrast (DIC) is a qualitative microscopy technique that shows the optical path length differences within a specimen. We propose ...

  3. Validation of Statistical Sampling Algorithms in Visual Sample Plan (VSP): Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Nuffer, Lisa L; Sego, Landon H.; Wilson, John E.; Hassig, Nancy L.; Pulsipher, Brent A.; Matzke, Brett D.

    2009-02-18

    The U.S. Department of Homeland Security, Office of Technology Development (OTD) contracted with a set of U.S. Department of Energy national laboratories, including the Pacific Northwest National Laboratory (PNNL), to write a Remediation Guidance for Major Airports After a Chemical Attack. The report identifies key activities and issues that should be considered by a typical major airport following an incident involving release of a toxic chemical agent. Four experimental tasks were identified that would require further research in order to supplement the Remediation Guidance. One of the tasks, Task 4, OTD Chemical Remediation Statistical Sampling Design Validation, dealt with statistical sampling algorithm validation. This report documents the results of the sampling design validation conducted for Task 4. In 2005, the Government Accountability Office (GAO) performed a review of the past U.S. responses to Anthrax terrorist cases. Part of the motivation for this PNNL report was a major GAO finding that there was a lack of validated sampling strategies in the U.S. response to Anthrax cases. The report (GAO 2005) recommended that probability-based methods be used for sampling design in order to address confidence in the results, particularly when all sample results showed no remaining contamination. The GAO also expressed a desire that the methods be validated, which is the main purpose of this PNNL report. The objective of this study was to validate probability-based statistical sampling designs and the algorithms pertinent to within-building sampling that allow the user to prescribe or evaluate confidence levels of conclusions based on data collected as guided by the statistical sampling designs. Specifically, the designs found in the Visual Sample Plan (VSP) software were evaluated. VSP was used to calculate the number of samples and the sample location for a variety of sampling plans applied to an actual release site. Most of the sampling designs validated are

  4. Reconstruction and Visualization of Fiber and Laminar Structure inthe Normal Human Heart from Ex Vivo DTMRI Data

    Energy Technology Data Exchange (ETDEWEB)

    Rohmer, Damien; Sitek, Arkadiusz; Gullberg, Grant T.

    2006-12-18

    Background - The human heart is composed of a helicalnetwork of muscle fibers. These fibers are organized to form sheets thatare separated by cleavage surfaces. This complex structure of fibers andsheets is responsible for the orthotropic mechanical properties ofcardiac muscle. The understanding of the configuration of the 3D fiberand sheet structure is important for modeling the mechanical andelectrical properties of the heart and changes in this configuration maybe of significant importance to understand the remodeling aftermyocardial infarction.Methods - Anisotropic least square filteringfollowed by fiber and sheet tracking techniques were applied to DiffusionTensor Magnetic Resonance Imaging (DTMRI) data of the excised humanheart. The fiber configuration was visualized by using thin tubes toincrease 3-dimensional visual perception of the complex structure. Thesheet structures were reconstructed from the DTMRI data, obtainingsurfaces that span the wall from the endo- to the epicardium. Allvisualizations were performed using the high-quality ray-tracing softwarePOV-Ray. Results - The fibers are shown to lie in sheets that haveconcave or convex transmural structure which correspond to histologicalstudies published in the literature. The fiber angles varied depending onthe position between the epi- and endocardium. The sheets had a complexstructure that depended on the location within the myocardium. In theapex region the sheets had more curvature. Conclusions - A high-qualityvisualization algorithm applied to demonstrated high quality DTMRI datais able to elicit the comprehension of the complex 3 dimensionalstructure of the fibers and sheets in the heart.

  5. Prevention of sexually transmitted diseases among visually impaired people: educational text validation 1

    Science.gov (United States)

    Oliveira, Giselly Oseni Barbosa; Cavalcante, Luana Duarte Wanderley; Pagliuca, Lorita Marlena Freitag; de Almeida, Paulo César; Rebouças, Cristiana Brasil de Almeida

    2016-01-01

    ABSTRACT Objective: to validate an educational text in the context of Sexually Transmitted Diseases (STD) for visually impaired persons, making it accessible to this population. Method: a validation study, in a virtual environment. Data collection occurred from May to September 2012 by emailing the subjects, and was composed by seven content experts about STDs. Analysis was based on the considerations of the experts about Objectives, Structure and Presentation, and Relevance. Results: on the Objectives and Structure and Presentation blocks, 77 (84.6%) and 48 (85.7%) were fully adequate or appropriate, respectively. In the Relevance block, items 3.2 - Allows transfer and generalization of learning, and 3.5 - Portrays aspects needed to clarify the family, showed bad agreement indices of 0.42 and 0.57, respectively. The analysis was followed by reformulating the text according to the relevant suggestions. Conclusion: the text was validated regarding the content of sexually transmitted diseases. A total of 35 stanzas were removed and nine others included, following the recommendations of the experts. PMID:27556880

  6. Validity, reliability, and responsiveness of a digital version of the visual analog scale.

    Science.gov (United States)

    Sindhu, Bhagwant S; Shechtman, Orit; Tuckey, Laura

    2011-01-01

    The design used in this study was a prospective cohort. Pain intensity levels recorded by the digital version of the visual analog scale (VAS-D) are easy to both score and share with other health care professionals. The purpose of the study was to examine the test-retest reliability, concurrent validity, and responsiveness of the VAS-D. Thirty-three people with upper extremity injuries reported pain intensity levels before and after performing four maximal grip contractions (pre- and postgripping). Our version of the VAS-D had high test-retest reliability (r=0.96) and good concurrent validity (r=0.84-0.97) with both the paper version of the VAS (VAS-P) and the verbal numerical rating scale (NRS-V). Responsiveness of the VAS-D was indicated by a significant increase in pain levels from pre- to postgripping. Similar responsiveness to that of the VAS-P and NRS-V was indicated by similar effect size coefficients and analysis of variance of pain change scores. In conclusion, the VAS-D is a reliable, valid, and responsive measure of pain intensity for people with upper extremity injuries. However, differences in accuracy (resolution) among the VAS-D, VAS-P, or NRS-V may render the three pain scales not fully compatible. Not applicable. Copyright © 2011 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  7. The validation of the visual analogue scale for patient satisfaction after total hip arthroplasty.

    Science.gov (United States)

    Brokelman, Roy B G; Haverkamp, Daniel; van Loon, Corné; Hol, Annemiek; van Kampen, Albert; Veth, Rene

    2012-06-01

    INTRODUCTION: Patient satisfaction becomes more important in our modern health care system. The assessment of satisfaction is difficult because it is a multifactorial item for which no golden standard exists. One of the potential methods of measuring satisfaction is by using the well-known visual analogue scale (VAS). In this study, we validated VAS for satisfaction. PATIENT AND METHODS: In this prospective study, we studied 147 patients (153 hips). The construct validity was measured using the Spearman correlation test that compares the satisfaction VAS with the Harris hip score, pain VAS at rest and during activity, Oxford hip score, Short Form 36 and Western Ontario McMaster Universities Osteoarthritis Index. The reliability was tested using the intra-class coefficient. RESULTS: The Pearson correlation test showed correlations in the range of 0.40-0.80. The satisfaction VAS had a high correlation between the pain VAS and Oxford hip score, which could mean that pain is one of the most important factors in patient satisfaction. The intra-class coefficient was 0.95. CONCLUSIONS: There is a moderate to mark degree of correlation between the satisfaction VAS and the currently available subjective and objective scoring systems. The intra-class coefficient of 0.95 indicates an excellent test-retest reliability. The VAS satisfaction is a simple instrument to quantify the satisfaction of a patient after total hip arthroplasty. In this study, we showed that the satisfaction VAS has a good validity and reliability.

  8. Further validation of the visual analogue scale for irritable bowel syndrome after use in clinical practice.

    Science.gov (United States)

    Bengtsson, Mariette; Persson, Jesper; Sjölund, Kristina; Ohlsson, Bodil

    2013-01-01

    The Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS), a self-rating questionnaire, was designed to measure symptoms and the effect of treatment in patients suffering from irritable bowel syndrome. The aim of this descriptive correlational study was to conduct further psychometric validation after the VAS-IBS had been used in clinical practice, translate it into English, and compare the results with controls. Forty-nine patients with irritable bowel syndrome (median age = 38 years old [range, 18-69 years]) were compared with 90 healthy persons (median age = 44 years old [range, 21-77 years]) who served as controls. The patients with irritable bowel syndrome completed 3 questionnaires: the VAS-IBS, the Gastrointestinal Symptom Rating Scale, and the Perception of Change of Symptoms. Controls completed only the VAS-IBS. Results showed that the VAS-IBS is a valid questionnaire that measures the degree of change of symptoms and discriminates between patients who have irritable bowel syndrome from those who do not. It is important to compare the VAS-IBS among different cultural populations so we suggest that the English version of the VAS-IBS should now be used in English-speaking countries and be further tested for validity and reliability with English-speaking patients.

  9. Visual analogue thermometer: a valid and useful instrument for measuring pain in burned patients.

    Science.gov (United States)

    Choinière, M; Auger, F A; Latarjet, J

    1994-06-01

    This study assessed the psychometric qualities of a new pain rating instrument--the visual analogue thermometer (VAT)--which was developed to measure pain in burned patients. The validity and utility of the VAT was assessed and compared with a conventional numeric (NUM) and adjective pain scale (ADJ) with a group of 103 burned patients and 51 nurses. Analyses of the results support the concurrent and construct validity of the VAT as a pain measure. Furthermore, the VAT gave more sensitive and precise pain measures than the ADJ and/or NUM scales. No major difference between the three scales emerged in the patients' preference. The same was true for the nurses' evaluation except for those who had more clinical experience with the VAT and who tended to prefer this scale for its accuracy and ease of utilization. The VAT appears to be a valid, sensitive and clinically useful tool to measure pain in burned patients. A systematic pain assessment procedure which can be easily implemented in burn care facilities is presented.

  10. Time Domain Strain/Stress Reconstruction Based on Empirical Mode Decomposition: Numerical Study and Experimental Validation

    Directory of Open Access Journals (Sweden)

    Jingjing He

    2016-08-01

    Full Text Available Structural health monitoring has been studied by a number of researchers as well as various industries to keep up with the increasing demand for preventive maintenance routines. This work presents a novel method for reconstruct prompt, informed strain/stress responses at the hot spots of the structures based on strain measurements at remote locations. The structural responses measured from usage monitoring system at available locations are decomposed into modal responses using empirical mode decomposition. Transformation equations based on finite element modeling are derived to extrapolate the modal responses from the measured locations to critical locations where direct sensor measurements are not available. Then, two numerical examples (a two-span beam and a 19956-degree of freedom simplified airfoil are used to demonstrate the overall reconstruction method. Finally, the present work investigates the effectiveness and accuracy of the method through a set of experiments conducted on an aluminium alloy cantilever beam commonly used in air vehicle and spacecraft. The experiments collect the vibration strain signals of the beam via optical fiber sensors. Reconstruction results are compared with theoretical solutions and a detailed error analysis is also provided.

  11. Reliability and validity of an automated computerized visual acuity and stereoacuity test in children using an interactive video game.

    Science.gov (United States)

    Ma, Dae Joong; Yang, Hee Kyung; Hwang, Jeong-Min

    2013-07-01

    To evaluate the test-retest reliability and validity of the new automated computerized distance visual acuity and stereoacuity test for children, which uses an interactive video game. Retrospective, observational case series. A total of 102 children aged between 3 and 7 years underwent the Snellen visual acuity test, the Distance Randot Stereotest, and the new automated computerized distance visual acuity and stereoacuity test. The test-retest reliability and validity of the automated computerized tests were assessed and compared with the Snellen visual acuity test and the Distance Randot Stereotest with frequency distributions of the differences, Bland-Altman plots, and Deming regression. The automated computerized distance visual acuity test had high test-retest reliability (95% limits of agreement ±0.18 logMAR, 90.0% of the differences within 0.2 logMAR) and acceptable validity as compared with the Snellen visual acuity chart (95% limits of agreement ±0.27 logMAR, 81.3% of the differences within 0.2 logMAR). The automated computerized distance stereoacuity test had high test-retest reliability (95% limits of agreement ±0.29 log arc second, 95.1% of the differences within 0.3 log arc second) and acceptable validity as compared with the Distance Randot Stereotest (95% limits of agreement ±0.35 log arc second, 93.9% of the differences within 0.3 log arc second). The new automated computerized distance visual acuity and stereoacuity test, which uses an interactive video game, has good reliability and acceptable validity compared with the Snellen visual acuity chart and the Distance Randot Stereotest. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Validation of the Total Visual Acuity Extraction Algorithm (TOVA) for Automated Extraction of Visual Acuity Data From Free Text, Unstructured Clinical Records.

    Science.gov (United States)

    Baughman, Douglas M; Su, Grace L; Tsui, Irena; Lee, Cecilia S; Lee, Aaron Y

    2017-03-01

    With increasing volumes of electronic health record data, algorithm-driven extraction may aid manual extraction. Visual acuity often is extracted manually in vision research. The total visual acuity extraction algorithm (TOVA) is presented and validated for automated extraction of visual acuity from free text, unstructured clinical notes. Consecutive inpatient ophthalmology notes over an 8-year period from the University of Washington healthcare system in Seattle, WA were used for validation of TOVA. The total visual acuity extraction algorithm applied natural language processing to recognize Snellen visual acuity in free text notes and assign laterality. The best corrected measurement was determined for each eye and converted to logMAR. The algorithm was validated against manual extraction of a subset of notes. A total of 6266 clinical records were obtained giving 12,452 data points. In a subset of 644 validated notes, comparison of manually extracted data versus TOVA output showed 95% concordance. Interrater reliability testing gave κ statistics of 0.94 (95% confidence interval [CI], 0.89-0.99), 0.96 (95% CI, 0.94-0.98), 0.95 (95% CI, 0.92-0.98), and 0.94 (95% CI, 0.90-0.98) for acuity numerators, denominators, adjustments, and signs, respectively. Pearson correlation coefficient was 0.983. Linear regression showed an R2 of 0.966 (P unstructured clinical notes and provides an open source method of data extraction. Automated visual acuity extraction through natural language processing can be a valuable tool for data extraction from free text ophthalmology notes.

  13. Genotet: An Interactive Web-based Visual Exploration Framework to Support Validation of Gene Regulatory Networks.

    Science.gov (United States)

    Yu, Bowen; Doraiswamy, Harish; Chen, Xi; Miraldi, Emily; Arrieta-Ortiz, Mario Luis; Hafemeister, Christoph; Madar, Aviv; Bonneau, Richard; Silva, Cláudio T

    2014-12-01

    Elucidation of transcriptional regulatory networks (TRNs) is a fundamental goal in biology, and one of the most important components of TRNs are transcription factors (TFs), proteins that specifically bind to gene promoter and enhancer regions to alter target gene expression patterns. Advances in genomic technologies as well as advances in computational biology have led to multiple large regulatory network models (directed networks) each with a large corpus of supporting data and gene-annotation. There are multiple possible biological motivations for exploring large regulatory network models, including: validating TF-target gene relationships, figuring out co-regulation patterns, and exploring the coordination of cell processes in response to changes in cell state or environment. Here we focus on queries aimed at validating regulatory network models, and on coordinating visualization of primary data and directed weighted gene regulatory networks. The large size of both the network models and the primary data can make such coordinated queries cumbersome with existing tools and, in particular, inhibits the sharing of results between collaborators. In this work, we develop and demonstrate a web-based framework for coordinating visualization and exploration of expression data (RNA-seq, microarray), network models and gene-binding data (ChIP-seq). Using specialized data structures and multiple coordinated views, we design an efficient querying model to support interactive analysis of the data. Finally, we show the effectiveness of our framework through case studies for the mouse immune system (a dataset focused on a subset of key cellular functions) and a model bacteria (a small genome with high data-completeness).

  14. Concurrent validity of the wide range assessment of visual motor abilities in typically developing children ages 4 to 11 years.

    Science.gov (United States)

    Obler, Doris R; Avi-Itzhak, Tamara

    2011-10-01

    Pediatric clinicians working with school-age children use the Wide Range Assessment of Visual Motor Abilities (WRAVMA) as a method for evaluating visual perception and motor skills in children despite limited information on concurrent validity. Whether it may be substituted for the Beery-Buktenica Developmental Test of Visual-Motor Integration (VMI) and has suitable estimates of concurrent validity were examined with a convenience sample of 91 typically developing children ages 4 to 11 years. No systematic concurrent validity between the WRAVMA and the VMI emerged. Only two subtests of the WRAVMA (Matching with Visual Perception, and Pegboard with Motor Coordination) gave scores statistically significantly correlated with those on the VMI, and these correlations were weak, accounting for very small amounts of the shared variance. As such, they have low clinical relevance. These findings do not provide evidence of concurrent validity to support the use of WRAVMA as an alternative method for the VMI for assessing children's visual perception and motor skills.

  15. Visual-Spatial Memory and Recall Test (V-SMART): validity and reliability.

    Science.gov (United States)

    Vik, Peter; Legarreta, Margaret; Riffel, Sarah

    2017-09-28

    Nonverbal memory decline is a concern associated with aging. Visuospatial memory tests often do not distinguish between learning, recall, or retrieval, yet such distinctions may help clarify the nature of memory difficulties. Further, many visuospatial tests rely on abilities not directly related to memory (e.g. graphomotor skill). The present study examined the feasibility and initial psychometric evidence of the Visual-Spatial Memory and Recall Test (V-SMART). Ninety-nine adults (71% women) were recruited from two sources: undergraduate students (n = 37) and healthy older adults (n = 62). Volunteers completed a brief battery of cognitive tests. Internal consistency and interrater reliability were strong. Principal Components Analysis supported the hypothesized learning and recall structure, and correlations with other memory tests supported external validity of the V-SMART as a visuospatial learning measure. Correlations with recall scores were less compelling yet likely reflected the intact recall among this generally healthy sample. These preliminary findings support the V-SMART as a visuospatial memory test. Evidence for validity was acceptable for learning indices; further examination of recall measures is needed.

  16. Reconstructive endovascular treatment of vertebral artery dissecting aneurysms with the Low-profile Visualized Intraluminal Support (LVIS) device.

    Science.gov (United States)

    Wang, Chuan-Chuan; Fang, Yi-Bin; Zhang, Ping; Zhu, Xuan; Hong, Bo; Xu, Yi; Liu, Jian-Min; Huang, Qing-Hai

    2017-01-01

    The Low-profile Visualized Intraluminal Support (LVIS) device is a new generation of self-expanding braided stent recently introduced in China for stent assisted coiling of intracranial aneurysms. The aim of our study is to evaluate the feasibility, safety, and efficacy of the LVIS device in reconstructive treatment of vertebral artery dissecting aneurysms (VADAs). We retrospectively reviewed the neurointerventional database of our institution from June 2014 to May 2016. Patients who underwent endovascular treatment of VADAs with LVIS stents were included in this study. Clinical presentation, aneurysmal characteristics, technical feasibility, procedural complications, and angiographic and clinical follow-up results were evaluated. 38 patients with VADAs who underwent treatment with LVIS stent were identified, including 3 ruptured VADAs. All VADAs were successfully treated with reconstructive techniques including the stent-assisted coiling (n = 34) and stenting only (n = 4). Post-procedural complications developed in 3 patients (7.9%) including two small brainstem infarctions and one delayed thromboembolic event. Complications resulted in one case of minor permanent morbidity (2.6%). There was no procedure-related mortality. The follow-up angiogram was available in 30 patients at an average of 8.3 months (range, 2 to 30 months), which revealed complete occlusion in 23 patients (76.7%), residual neck in five patients (16.7%), and residual sac in two patients (6.7%). The follow-up of 25 aneurysms with incomplete immediate occlusion revealed 22 aneurysms (88%) with improvement in the Raymond class. One aneurysm (3.3%) showed recanalization and required retreatment. Clinical followed-up at 5-28 months (mean 14.1 months) was achieved in 36 patients because two patients died of pancreatic cancer and basal ganglia hemorrhage, respectively. No new neurologic deterioration or aneurysm (re)bleeding was observed. Our preliminary experience with reconstruction of VADAs with the

  17. Multi-country evaluation of affective experience: validation of an abbreviated version of the day reconstruction method in seven countries.

    Science.gov (United States)

    Ayuso-Mateos, José Luis; Miret, Marta; Caballero, Francisco Félix; Olaya, Beatriz; Haro, Josep Maria; Kowal, Paul; Chatterji, Somnath

    2013-01-01

    The Day Reconstruction Method (DRM) was developed to assess affective states as measures of experienced well-being. The present study aimed to validate an abbreviated version of the DRM in a representative sample of the population in seven countries (China, Ghana, India, Mexico, Russia, South Africa, and Spain), and to examine whether there are country differences in affect and in the relationships among the activities based on the similarity of the affect associated with each of them. Interviews were conducted with 47,222 non-institutionalized adults from seven countries, using an abbreviated version of the DRM. A cluster analysis was carried out to classify activities on the basis of the similarity of the associated affect. In each country, the factorial structure of the affect adjectives was tested through Confirmatory Factor Analysis. Internal consistency and construct validity were also assessed. Moreover, the differences in affect across countries and the diurnal cycles of affect were evaluated. The DRM showed adequate psychometric properties regarding reliability and construct validity in all countries. Respondents from Ghana and South Africa reported more positive net affect whereas Indian respondents reported less positive net affect. Most of the countries showed a similar diurnal variation of affect, which tended to improve throughout the day. The results show that this abbreviated version of the DRM is a useful tool for multi-country evaluation of experienced well-being.

  18. Non-Destructive Approaches for the Validation of Visually Observed Spatial Patterns of Decay

    Science.gov (United States)

    Johnston, Brian; McKinley, Jennifer; Warke, Patricia; Ruffell, Alastair

    2017-04-01

    Historical structures are regarded as a built legacy that is passed down through the generations and as such the conservation and restoration of these buildings is of great importance to governmental, religious and charitable organisations. As these groups play the role of custodians of this built heritage, they are therefore keen that the approaches employed in these studies of stone condition are non-destructive in nature. Determining sections of facades requiring repair work is often achieved through a visual conditional inspection of the stonework by a specialist. However, these reports focus upon the need to identify blocks requiring restorative action rather than the determination of spatial trends that lead to the identification of causes. This fixation on decay occurring at the block scale results in the spatial distribution of weathering present at the larger 'wall' scale appearing to have developed chaotically. Recent work has shown the importance of adopting a geomorphological focus when undertaking visual inspection of the facades of historical buildings to overcome this issue. Once trends have been ascertained, they can be used to bolster remedial strategies that target the sources of decay rather than just undertaking an aesthetic treatment of symptoms. Visual inspection of the study site, Fitzroy Presbyterian Church in Belfast, using the geomorphologically driven approach revealed three features suggestive of decay extending beyond the block scale. Firstly, the influence of architectural features on the susceptibility of blocks to decay. Secondly, the impact of the fluctuation in groundwater rise over the seasons and the influence of aspect upon this process. And finally, the interconnectivity of blocks, due to deteriorating mortar and poor repointing, providing conduits for the passage of moisture. Once these patterns were identified, it has proven necessary to validate the outcome of the visual inspection using other techniques. In this study

  19. Validation of a visual analogue score (LRTI-VAS) in non-CF bronchiectasis.

    Science.gov (United States)

    Altenburg, Josje; Wortel, Kim; de Graaff, Casper S; van der Werf, Tjip S; Boersma, Wim G

    2016-03-01

    Quality of life in patients with non-cystic fibrosis (non-CF) bronchiectasis is largely defined by respiratory symptoms. To date, no disease-specific tool for symptom measurement in this patient group was available. We developed the lower respiratory tract infections - visual analogue scale (LRTI-VAS) in order to quickly and conveniently quantify symptoms in non-CF bronchiectasis. This study aimed to validate LRTI-VAS for use in non-CF bronchiectasis. This study included outpatients with radiologically proven bronchiectasis and no evidence of CF. Results of LRTI-VAS were compared with other markers of disease activity {lung function parameters, oxygen saturation and three health-related quality of life questionnaires [Medical Outcomes Study Short-Form 36 Health Survey (SF-36), St Georges Respiratory Questionnaire (SGRQ) and Leicester Cough Questionnaire (LCQ)]} and validity, reliability and responsiveness were assessed. Thirty stable and 30 exacerbating participants completed the LRTI-VAS questionnaire. When testing for repeatability on two separate occasions, no statistically significant difference between total scores was found {1.4 [standard deviation (SD)] 5.3}, P = 0.16). Internal consistency was high across items (Cronbach's alpha 0.86). Correlation with SGRQ, SF-36 and LCQ total scores was high. Following antibiotic treatment, mean (SD) LRTI-VAS total score improved from 18.1 (SD 9.9) to 26.1 (SD 6.6) (P VAS showed excellent validity, reliability and responsiveness to change and therefore appears a reliable tool for symptom measurement in non-CF bronchiectasis. © 2014 John Wiley & Sons Ltd.

  20. Validity and Reliability of Visual Analog Scale Foot and Ankle: The Turkish Version.

    Science.gov (United States)

    Gur, Gozde; Turgut, Elif; Dilek, Burcu; Baltaci, Gul; Bek, Nilgun; Yakut, Yavuz

    The present study tested the reliability and validity of the Turkish version of the visual analog scale foot and ankle (VAS-FA) among healthy subjects and patients with foot problems. A total of 128 participants, 65 healthy subjects and 63 patients with foot problems, were evaluated. The VAS-FA was translated into Turkish and administered to the 128 subjects on 2 separate occasions with a 5-day interval. The test-retest reliability and internal consistency were assessed with the intraclass correlation coefficient and Cronbach's α. The validity was assessed using the correlations with Turkish versions of the Foot Function Index, the Foot and Ankle Outcome Score, and the Short-Form 36-item Health Survey. A statistically significant difference was found between the healthy group and the patient group in the overall score and subscale scores of the VAS-FA (p VAS-FA was very good, and the test-retest reliability was excellent. Adequate to good correlations were found between the overall VAS-FA score and the Foot Function Index, Foot and Ankle Outcome Score, and Short-Form 36-item Health Survey scores in the healthy and patient groups both. The Turkish version of the VAS-FA is sensitive enough to distinguish foot and ankle-specific pathologic conditions from asymptomatic conditions. The Turkish version of the VAS-FA is a reliable and valid method and can be used for foot-related problems. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  1. Visual Utilization During Postural Control in Anterior Cruciate Ligament- Deficient and -Reconstructed Patients: Systematic Reviews and Meta-Analyses.

    Science.gov (United States)

    Wikstrom, Erik A; Song, Kyeongtak; Pietrosimone, Brian G; Blackburn, J Troy; Padua, Darin A

    2017-10-01

    To determine whether anterior cruciate ligament-deficient (ACL-D) individuals and individuals with a reconstructed anterior cruciate ligament (ACL-R) rely more heavily on visual information to maintain postural control. PubMed, CINAHL, and SPORTDiscus databases were searched from their earliest available date to May 24, 2016, using a combination of keywords. Articles were included if they reported any instrumented static single-leg balance outcome in both a patient and control sample. The means and SDs of these outcomes must have been reported with both eyes open and eyes closed. Sample sizes, means, and SDs of single-leg balance measures for each group's eyes open and eyes closed testing conditions were extracted. The methodological quality of included studies was independently evaluated by multiple authors using an adapted version of the Quality Index. Effect sizes were calculated by dividing the differences in change between eyes closed and eyes open in the ACL-D and control group and the ACL-R and control group by the pooled SD from the eyes closed trials for each analysis. Significant differences between the ACL-D and control group (effect size, -1.66; 95% confidence interval [CI], -2.90 to -.41) were noted. The ACL-R and control group were not different (effect size, -.61; 95% CI, -2.17 to .95). ACL-D individuals but not individuals with ACL-R demonstrate a greater reliance on visual information during single-leg stance compared with healthy individuals. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  2. Simulation of heterogeneous molecular delivery in tumours using μCT reconstructions and MRI validation.

    Science.gov (United States)

    Wittenborn, Thomas Rea; Nielsen, Thomas; Thomsen, Jesper Skovhus; Horsman, Michael Robert; Nygaard, Jens Vinge

    2016-11-01

    Utilizing the detailed vascular network obtained from micro-computed tomography (μCT) to establish a mathematical model of the temporal molecular distribution within a murine C3H mammary carcinoma. Female CDF1 mice with a C3H mammary carcinoma on the right rear foot were used in this study. Dynamic information for each tumour was achieved by Dynamic Contrast Enhanced-Magnetic Resonance Imaging (DCE-MRI) on a 16.4 T system. Detailed morphologic information on the tumour vasculature was obtained by ex vivo μCT and compared to CD34 immunohistochemical staining of tissue sections. The reconstructed vascular network served as origin for the diffusion (described by the apparent diffusion coefficient) within the tumour (the restricted volume described by the interstitial volume fraction derived from DCE-MRI). The resulting partial differential equation was solved using Finite-Element and a combined mathematical graph describing molecular distribution within the tumour was obtained. The established molecular distribution model predicted a heterogeneous distribution throughout the tumour related to the layout of the vascular network. Central tumour section concentration-time curves estimated from the established molecular distribution model were compared with physical measurements obtained by DCE-MRI of the same tumours and showed excellent correlation. A mathematical model describing temporal molecular distribution based on detailed vascular network structures was established and compared to DCE-MRI. The improved morphological insight will enhance future studies of heterogeneous tumours. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Validating coronal magnetic field reconstruction methods using solar wind simulations and synthetic imagery

    Science.gov (United States)

    Pinto, Rui; Rouillard, Alexis; Génot, Vincent; Amari, Tahar; Buchlin, Eric; Arge, Nick; Sasso, Clementina; Andretta, Vincenzo; Bemporad, Alessandro

    2017-04-01

    We present an ongoing effort within the ESA Modeling and Data Analysis Working Group (MADAWG) to determine automatically the magnetic connectivity between the solar surface and any point in interplanetary space. The goal is to produce predictions of the paths and propagation delays of plasma and energetic particle propagation. This is a key point for the data exploitation of the Solar Orbiter and Solar Probe Plus missions, and for establishing connections between remote and in-situ data. The background coronal magnetic field is currently determined via existing surface magnetograms and PFSS extrapolations, but the interface is ready to include different combinations of coronal field reconstruction methods (NLFFF, Solar Models), wind models (WSA, MULTI-VP), heliospheric models (Parker spiral, ENLIL, EUHFORIA). Some model realisations are also based on advanced magnetograms based on data assimilation techniques (ADAPT) and the HELCATS catalogue of simulations. The results from the different models will be combined in order to better assess the modelling uncertainties. The wind models provide synthetic white-light and EUV images which are compared to coronographic imagery, and the heliospheric models provide estimations of synthetic in-situ data wich are compared to spacecraft data. A part of this is work (wind modelling) is supported by the FP7 project #606692 (HELCATS).

  4. Validation of a Mexican food photograph album as a tool to visually estimate food amounts in adolescents

    National Research Council Canada - National Science Library

    Bernal-Orozco, M Fernanda; Vizmanos-Lamotte, Barbara; Rodríguez-Rocha, Norma P; Macedo-Ojeda, Gabriela; Orozco-Valerio, María; Rovillé-Sausse, Françoise; León-Estrada, Sandra; Márquez-Sandoval, Fabiola; Fernández-Ballart, Joan D

    2013-01-01

    The aim of the present study was to validate a food photograph album (FPA) as a tool to visually estimate food amounts, and to compare this estimation with that attained through the use of measuring cups (MC) and food models (FM...

  5. Psychometric Validation and Normative Data of a Second Chinese Version of the Hooper Visual Organization Test in Children

    Science.gov (United States)

    Lin, Yueh-Hsien; Su, Chwen-Yng; Guo, Wei-Yuan; Wuang, Yee-Pay

    2012-01-01

    The Hooper Visual Organization Test (HVOT) is a measure of visuosynthetic ability. Previously, the psychometric properties of the HVOT have been evaluated for Chinese-speaking children aged 5-11 years. This study reports development and further evidence of reliability and validity for a second version involving an extended age range of healthy…

  6. In Silico Genome-Scale Reconstruction and Validation of the Corynebacterium glutamicum Metabolic Network

    DEFF Research Database (Denmark)

    Kjeldsen, Kjeld Raunkjær; Nielsen, J.

    2009-01-01

    A genome-scale metabolic model of the Gram-positive bacteria Corynebacterium glutamicum ATCC 13032 was constructed comprising 446 reactions and 411 metabolite, based on the annotated genome and available biochemical information. The network was analyzed using constraint based methods. The model...... was extensively validated against published flux data, and flux distribution values were found to correlate well between simulations and experiments. The split pathway of the lysine synthesis pathway of C. glutamicum was investigated, and it was found that the direct dehydrogenase variant gave a higher lysine...

  7. Content validity of a home-based person-environment interaction assessment tool for visually impaired adults.

    Science.gov (United States)

    Carignan, Mathieu; Rousseau, Jacqueline; Gresset, Jacques; Couturier, Julie-Anne

    2008-01-01

    Home-based assessments require in-depth analyses of daily living difficulties. No assessment tool that has been validated with visually impaired adult subjects has allowed such analysis. This research adapted a home-based person-environment interaction assessment tool designed for persons who are visually impaired. The Model of Competence, an explanatory model of the person-environment relationship, served as the conceptual framework. A qualitative study was conducted with professionals, visually impaired persons, and informal caregivers. Focus groups and semistructured individual interviews were used for data collection. The content and form had to be modified to adapt the assessment tool for use with visually impaired adults. This qualitative study documents the content validity of the Home Assessment of Person-Environment Interaction-Visual Version. The assessment tool will provide vision rehabilitation professionals better screens and explanations of handicap-created situations faced by visually impaired persons at home. By using a structured analysis based on a person-environment theoretical model, this new assessment tool fills a scientific and clinical gap, optimizes the evaluation process, and documents the intervention plan by providing an understanding of the home context.

  8. The Visual Analogue WOMAC 3.0 scale - internal validity and responsiveness of the VAS version

    Science.gov (United States)

    2010-01-01

    Background Many people suffer with Osteoarthritis (OA) and subsequent morbidity. Therefore, measuring outcome associated with OA is important. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) has been a widely used patient reported outcome in OA. However, there is relatively little evidence to support the use of the Visual Analogue Scale (VAS) version of the scale. We aimed to explore the internal validity and responsiveness of this VAS version of the WOMAC. Methods Patients with chronic hip or knee pain of mechanical origin, waiting for a hip or knee joint replacement completed the WOMAC as part of a study to investigate the effects of acupuncture and placebo controls. Validity was tested using factor analysis and Rasch analysis, and responsiveness using standardised response means. Results Two hundred and twenty one patients (mean age 66.8, SD 8.29, 58% female) were recruited. Factor and Rasch analysis confirmed unidimensional Pain and Physical Functioning scales, capable of transformation to interval scaling and invariant over time. Some Differential Item Functioning (DIF) was observed, but this cancelled out at the test level. The Stiffness scale fitted the Rasch model but adjustments for DIF could not be made due to the shortness of the scale. Using the interval transformed data, Standardised Response Means were smaller than when using the raw, ordinal data. Conclusions The WOMAC Pain and Physical Functioning subscales satisfied unidimensionality and ordinal scaling tests, and the ability to transform to an interval scale. Some Differential Item Functioning was observed, but this cancelled out at the test level and, by doing so, at the same time removed the disturbance of unidimensionality. The scaling characteristics of sets of items which use VAS require further analysis, as it would appear that they can lead to spurious levels of responsiveness and scale compression because they exaggerate the distortion of the ordinal scale. Trial

  9. The Visual Analogue WOMAC 3.0 scale - internal validity and responsiveness of the VAS version

    Directory of Open Access Journals (Sweden)

    Tennant Alan

    2010-04-01

    Full Text Available Abstract Background Many people suffer with Osteoarthritis (OA and subsequent morbidity. Therefore, measuring outcome associated with OA is important. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC has been a widely used patient reported outcome in OA. However, there is relatively little evidence to support the use of the Visual Analogue Scale (VAS version of the scale. We aimed to explore the internal validity and responsiveness of this VAS version of the WOMAC. Methods Patients with chronic hip or knee pain of mechanical origin, waiting for a hip or knee joint replacement completed the WOMAC as part of a study to investigate the effects of acupuncture and placebo controls. Validity was tested using factor analysis and Rasch analysis, and responsiveness using standardised response means. Results Two hundred and twenty one patients (mean age 66.8, SD 8.29, 58% female were recruited. Factor and Rasch analysis confirmed unidimensional Pain and Physical Functioning scales, capable of transformation to interval scaling and invariant over time. Some Differential Item Functioning (DIF was observed, but this cancelled out at the test level. The Stiffness scale fitted the Rasch model but adjustments for DIF could not be made due to the shortness of the scale. Using the interval transformed data, Standardised Response Means were smaller than when using the raw, ordinal data. Conclusions The WOMAC Pain and Physical Functioning subscales satisfied unidimensionality and ordinal scaling tests, and the ability to transform to an interval scale. Some Differential Item Functioning was observed, but this cancelled out at the test level and, by doing so, at the same time removed the disturbance of unidimensionality. The scaling characteristics of sets of items which use VAS require further analysis, as it would appear that they can lead to spurious levels of responsiveness and scale compression because they exaggerate the distortion of

  10. Examining ecological validity in social interaction: problems of visual fidelity, gaze, and social potential.

    Science.gov (United States)

    Reader, Arran T; Holmes, Nicholas P

    2016-01-01

    Social interaction is an essential part of the human experience, and much work has been done to study it. However, several common approaches to examining social interactions in psychological research may inadvertently either unnaturally constrain the observed behaviour by causing it to deviate from naturalistic performance, or introduce unwanted sources of variance. In particular, these sources are the differences between naturalistic and experimental behaviour that occur from changes in visual fidelity (quality of the observed stimuli), gaze (whether it is controlled for in the stimuli), and social potential (potential for the stimuli to provide actual interaction). We expand on these possible sources of extraneous variance and why they may be important. We review the ways in which experimenters have developed novel designs to remove these sources of extraneous variance. New experimental designs using a 'two-person' approach are argued to be one of the most effective ways to develop more ecologically valid measures of social interaction, and we suggest that future work on social interaction should use these designs wherever possible.

  11. [Italian validation of Multiple Visual Analogue Scales for Bipolarity (MVAS-BP) of Ahearn and Carroll].

    Science.gov (United States)

    Staccini, Laura; Tomba, Elena; Ottolini, Fedra; Ruini, Chiara; Fava, Giovanni Andrea

    2012-01-01

    The aim of the present study was to validate the Italian version and to assess the clinimetric properties of Ahearn and Carroll's Visual Analogue Scales for Bipolarity (MVAS-BP), a self-rating questionnaire measuring affective state. MVAS-BP consist of 26 items: 1 item assesses overall mood, 2 items anger and 23 items are based on the Carroll model of bipolar disorder (Consummatory Reward, Incentive Reward, Central Pain, Psychomotor Regulation). MVAS-BP have been translated into Italian and administered with Kellner's Symptom Questionnaire (SQ), Ryff's Psychological Well-Being Scales (PWB), and Cloninger's Tridimensional Personality Questionnaire (TPQ) to a normative sample of 450 people. The assessment was repeated after one month. Test-retest reliability, means scores, differences according to sociodemographic variables and correlations among the scales of MVAS-BP, SQ, PWB and TPQ were performed in order to assess clinimetric properties. Test-retest coefficients were highly significant. Significant sex differences were found in the scales of consummatory reward, central pain, psychomotor regulation and anger. MVAS-BP scales were significantly related with symptom and well-being scales, but with very low correlation coefficients, and only with one personality dimension, TPQ Harm Avoidance. MVAS-BP has been found to possess clinimetric properties and to record specific and different information from those investigated by other questionnaires.

  12. Screening for hearing, visual and dual sensory impairment in older adults using behavioural cues: a validation study.

    Science.gov (United States)

    Roets-Merken, Lieve M; Zuidema, Sytse U; Vernooij-Dassen, Myrra J F J; Kempen, Gertrudis I J M

    2014-11-01

    This study investigated the psychometric properties of the Severe Dual Sensory Loss screening tool, a tool designed to help nurses and care assistants to identify hearing, visual and dual sensory impairment in older adults. Construct validity of the Severe Dual Sensory Loss screening tool was evaluated using Crohnbach's alpha and factor analysis. Interrater reliability was calculated using Kappa statistics. To evaluate the predictive validity, sensitivity and specificity were calculated by comparison with the criterion standard assessment for hearing and vision. The criterion used for hearing impairment was a hearing loss of ≥40 decibel measured by pure-tone audiometry, and the criterion for visual impairment was a visual acuity of ≤0.3 diopter or a visual field of ≤0.3°. Feasibility was evaluated by the time needed to fill in the screening tool and the clarity of the instruction and items. Prevalence of dual sensory impairment was calculated. A total of 56 older adults receiving aged care and 12 of their nurses and care assistants participated in the study. Crohnbach's alpha was 0.81 for the hearing subscale and 0.84 for the visual subscale. Factor analysis showed two constructs for hearing and two for vision. Kappa was 0.71 for the hearing subscale and 0.74 for the visual subscale. The predictive validity showed a sensitivity of 0.71 and a specificity of 0.72 for the hearing subscale; and a sensitivity of 0.69 and a specificity of 0.78 for the visual subscale. The optimum cut-off point for each subscale was score 1. The nurses and care assistants reported that the Severe Dual Sensory Loss screening tool was easy to use. The prevalence of hearing and vision impairment was 55% and 29%, respectively, and that of dual sensory impairment was 20%. The Severe Dual Sensory Loss screening tool was compared with the criterion standards for hearing and visual impairment and was found a valid and reliable tool, enabling nurses and care assistants to identify hearing

  13. MEVA--An Interactive Visualization Application for Validation of Multifaceted Meteorological Data with Multiple 3D Devices.

    Directory of Open Access Journals (Sweden)

    Carolin Helbig

    differences between simulation runs. In an iterative development process, our easy-to-use application was developed in close cooperation with meteorologists and visualization experts. The usability of the application has been validated with user tests. We report on how this application supports the users to prove and disprove existing hypotheses and discover new insights. In addition, the application has been used at public events to communicate research results.

  14. MEVA--An Interactive Visualization Application for Validation of Multifaceted Meteorological Data with Multiple 3D Devices.

    Science.gov (United States)

    Helbig, Carolin; Bilke, Lars; Bauer, Hans-Stefan; Böttinger, Michael; Kolditz, Olaf

    2015-01-01

    simulation runs. In an iterative development process, our easy-to-use application was developed in close cooperation with meteorologists and visualization experts. The usability of the application has been validated with user tests. We report on how this application supports the users to prove and disprove existing hypotheses and discover new insights. In addition, the application has been used at public events to communicate research results.

  15. Visual C++ Implementation of Sinogram-based Adaptive Iterative Reconstruction for Sparse View X-Ray CT

    CERN Document Server

    Trinca, D; Wang, Y; Mamyrbayev, T; Libin, E

    2016-01-01

    With the availability of more powerful computing processors, iterative reconstruction algorithms have recently been successfully implemented as an approach to achieving significant dose reduction in X-ray CT. In this report, we describe our proposal of an adaptive iterative reconstruction algorithm for X-ray CT, that is shown to provide results comparable to those obtained by proprietary algorithms, both in terms of reconstruction accuracy and execution time. Implementation code in the C language is provided, along with example of user interface.

  16. Visual C++ Implementation of Sinogram-based Adaptive Iterative Reconstruction for Sparse View X-Ray CT

    OpenAIRE

    Trinca, D.; Zhong, Y.; Wang, Y.; Mamyrbayev, T.; Libin, E.

    2016-01-01

    With the availability of more powerful computing processors, iterative reconstruction algorithms have recently been successfully implemented as an approach to achieving significant dose reduction in X-ray CT. In this report, we describe our proposal of an adaptive iterative reconstruction algorithm for X-ray CT, that is shown to provide results comparable to those obtained by proprietary algorithms, both in terms of reconstruction accuracy and execution time. Implementation code in the C lang...

  17. The PedsQL™ Present Functioning Visual Analogue Scales: preliminary reliability and validity

    Directory of Open Access Journals (Sweden)

    Varni James W

    2006-10-01

    Full Text Available Abstract Background The PedsQL™ Present Functioning Visual Analogue Scales (PedsQL™ VAS were designed as an ecological momentary assessment (EMA instrument to rapidly measure present or at-the-moment functioning in children and adolescents. The PedsQL™ VAS assess child self-report and parent-proxy report of anxiety, sadness, anger, worry, fatigue, and pain utilizing six developmentally appropriate visual analogue scales based on the well-established Varni/Thompson Pediatric Pain Questionnaire (PPQ Pain Intensity VAS format. Methods The six-item PedsQL™ VAS was administered to 70 pediatric patients ages 5–17 and their parents upon admittance to the hospital environment (Time 1: T1 and again two hours later (Time 2: T2. It was hypothesized that the PedsQL™ VAS Emotional Distress Summary Score (anxiety, sadness, anger, worry and the fatigue VAS would demonstrate moderate to large effect size correlations with the PPQ Pain Intensity VAS, and that patient" parent concordance would increase over time. Results Test-retest reliability was demonstrated from T1 to T2 in the large effect size range. Internal consistency reliability was demonstrated for the PedsQL™ VAS Total Symptom Score (patient self-report: T1 alpha = .72, T2 alpha = .80; parent proxy-report: T1 alpha = .80, T2 alpha = .84 and Emotional Distress Summary Score (patient self-report: T1 alpha = .74, T2 alpha = .73; parent proxy-report: T1 alpha = .76, T2 alpha = .81. As hypothesized, the Emotional Distress Summary Score and Fatigue VAS were significantly correlated with the PPQ Pain VAS in the medium to large effect size range, and patient and parent concordance increased from T1 to T2. Conclusion The results demonstrate preliminary test-retest and internal consistency reliability and construct validity of the PedsQL™ Present Functioning VAS instrument for both pediatric patient self-report and parent proxy-report. Further field testing is required to extend these initial

  18. The PedsQL™ Present Functioning Visual Analogue Scales: preliminary reliability and validity

    Science.gov (United States)

    Sherman, Sandra A; Eisen, Sarajane; Burwinkle, Tasha M; Varni, James W

    2006-01-01

    Background The PedsQL™ Present Functioning Visual Analogue Scales (PedsQL™ VAS) were designed as an ecological momentary assessment (EMA) instrument to rapidly measure present or at-the-moment functioning in children and adolescents. The PedsQL™ VAS assess child self-report and parent-proxy report of anxiety, sadness, anger, worry, fatigue, and pain utilizing six developmentally appropriate visual analogue scales based on the well-established Varni/Thompson Pediatric Pain Questionnaire (PPQ) Pain Intensity VAS format. Methods The six-item PedsQL™ VAS was administered to 70 pediatric patients ages 5–17 and their parents upon admittance to the hospital environment (Time 1: T1) and again two hours later (Time 2: T2). It was hypothesized that the PedsQL™ VAS Emotional Distress Summary Score (anxiety, sadness, anger, worry) and the fatigue VAS would demonstrate moderate to large effect size correlations with the PPQ Pain Intensity VAS, and that patient" parent concordance would increase over time. Results Test-retest reliability was demonstrated from T1 to T2 in the large effect size range. Internal consistency reliability was demonstrated for the PedsQL™ VAS Total Symptom Score (patient self-report: T1 alpha = .72, T2 alpha = .80; parent proxy-report: T1 alpha = .80, T2 alpha = .84) and Emotional Distress Summary Score (patient self-report: T1 alpha = .74, T2 alpha = .73; parent proxy-report: T1 alpha = .76, T2 alpha = .81). As hypothesized, the Emotional Distress Summary Score and Fatigue VAS were significantly correlated with the PPQ Pain VAS in the medium to large effect size range, and patient and parent concordance increased from T1 to T2. Conclusion The results demonstrate preliminary test-retest and internal consistency reliability and construct validity of the PedsQL™ Present Functioning VAS instrument for both pediatric patient self-report and parent proxy-report. Further field testing is required to extend these initial findings to other

  19. Assessing visual control during simulated and live operations: gathering evidence for the content validity of simulation using eye movement metrics.

    Science.gov (United States)

    Vine, Samuel J; McGrath, John S; Bright, Elizabeth; Dutton, Thomas; Clark, James; Wilson, Mark R

    2014-06-01

    Although virtual reality (VR) simulators serve an important role in the training and assessment of surgeons, they need to be evaluated for evidence of validity. Eye-tracking technology and measures of visual control have been used as an adjunct to the performance parameters produced by VR simulators to help in objectively establishing the construct validity (experts vs. novices) of VR simulators. However, determining the extent to which VR simulators represent the real procedure and environment (content validity) has largely been a subjective process undertaken by experienced surgeons. This study aimed to examine the content validity of a VR transurethral resection of the prostate (TURP) simulator by comparing visual control metrics taken during simulated and real TURP procedures. Eye-tracking data were collected from seven surgeons performing 14 simulated TURP operations and three surgeons performing 15 real TURP operations on live patients. The data were analyzed offline, and visual control metrics (number and duration of fixations, percentage of time the surgeons fixated on the screen) were calculated. The surgeons displayed more fixations of a shorter duration and spent less time fixating on the video monitor during the real TURP than during the simulated TURP. This could have been due to (1) the increased complexity of the operating room (OR) environment (2) the decreased quality of the image of the urethra and associated anatomy (compared with the VR simulator), or (3) the impairment of visual attentional control due to the increased levels of stress likely experienced in the OR. The findings suggest that the complexity of the environment surrounding VR simulators needs to be considered in the design of effective simulated training curricula. The study also provides support for the use of eye-tracking technology to assess the content validity of simulation and to examine psychomotor processes during live operations.

  20. Psychometric validation of the Taiwan Chinese version of the 25-Item National Eye Institute Visual Functioning Questionnaire.

    Science.gov (United States)

    Lin, Jen-Chieh; Chie, Wei-Chu

    2010-06-01

    To evaluate the reliability and construct validity of a Taiwan Chinese version of the 25-Item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ 25) in patients with visual impairment. The NEI-VFQ 25 was translated and adapted into the Taiwan Chinese version. In total, 222 patients responded to the questionnaire. To examine reliability, Cronbach's alpha for each subscale was used as an index of internal consistency. Test-retest reliability was evaluated with intraclass correlation coefficients. Regarding construct validity, both convergent and discriminant validities were calculated by means of multi-trait analysis. Clinical validity was examined by correlation of clinical measurements and subscale scores and known-groups comparison. Finally, correlation between different subscales was examined to evaluate hypothetical relationship between subscales. Five patient groups were studied, each including participants with a single cause of visual impairment. Group 1 consisted of 53 cataract patients; group 2 included 51 subjects with glaucoma; group 3 included 36 subjects with age-related macular degeneration (ARMD); and group 4 included 48 subjects with diabetic retinopathy. Thirty-four individuals with uncorrected refractive error comprised the control group. NEI-VFQ scores (mean +/- SD) for the cataract, glaucoma, ARMD, diabetic retinopathy and control groups were: 73.5 +/- 17.1, 69.2 +/- 20.4, 62.3 +/- 23.7, 63.7 +/- 20.8 and 80.7 +/- 12.0, respectively. Item analysis revealed moderate data skewing. Cronbach's alpha coefficients of subscales ranged from 0.956 (mental health) to 0.964 (near activities). Intraclass correlation coefficients ranged from 0.41 (driving) to 0.846 (distance activities). All items passed the convergent and discriminant validity tests. Moderate correlations were detected between visual acuity and the 'general vision', 'distance activities' and 'near activities' subscales. Significant correlations were detected between visual

  1. Prevention of sexually transmitted diseases among visually impaired people: educational text validation.

    Science.gov (United States)

    Oliveira, Giselly Oseni Barbosa; Cavalcante, Luana Duarte Wanderley; Pagliuca, Lorita Marlena Freitag; Almeida, Paulo César de; Rebouças, Cristiana Brasil de Almeida

    2016-08-18

    to validate an educational text in the context of Sexually Transmitted Diseases (STD) for visually impaired persons, making it accessible to this population. a validation study, in a virtual environment. Data collection occurred from May to September 2012 by emailing the subjects, and was composed by seven content experts about STDs. Analysis was based on the considerations of the experts about Objectives, Structure and Presentation, and Relevance. on the Objectives and Structure and Presentation blocks, 77 (84.6%) and 48 (85.7%) were fully adequate or appropriate, respectively. In the Relevance block, items 3.2 - Allows transfer and generalization of learning, and 3.5 - Portrays aspects needed to clarify the family, showed bad agreement indices of 0.42 and 0.57, respectively. The analysis was followed by reformulating the text according to the relevant suggestions. the text was validated regarding the content of sexually transmitted diseases. A total of 35 stanzas were removed and nine others included, following the recommendations of the experts. validar texto educativo no contexto das doenças sexualmente transmissíveis para pessoas com deficiência visual para torná-lo acessível a essa população. estudo de validação, em ambiente virtual. Coleta de dados de maio a setembro de 2012, por meio da utilização dos e-mails eletrônicos dos sujeitos, compostos por sete especialistas em conteúdo na temática, através de instrumento próprio. Análise ocorreu com base nas considerações dos especialistas sobre os Objetivos, Estrutura e Apresentação e Relevância. nos blocos de Objetivos e Estrutura e Apresentação, 77 (84,6%) e 48 (85,7%) eram totalmente adequados ou adequados, respectivamente. No bloco de Relevância, os itens 3.2 - Permite transferência e generalização da aprendizagem, e 3.5 - Mostra aspectos necessários para informar a família, revelaram índices de concordância ruins de 0,42 e 0,57, respectivamente. Após a análise, o texto foi

  2. TU-E-BRB-06: Best in Physics (Therapy) - Development and Experimental Validation of EPID-Based 4D Dose Reconstruction.

    Science.gov (United States)

    Lin, M; Li, J; Koren, S; Fan, J; Wang, L; Yin, G; Ma, C

    2012-06-01

    To develop and validate an EPID-based 4D patient dose reconstruction framework accounting for linac delivery uncertainties, interfractional and intrafractional motions, and interplay effect. Patients with fiducial markers were scanned with 4D-CT for SBRT planning. Before treatment, in-room 4D-CT was performed. Both the MLC and the tumor movements were tracked by continuously acquiring EPID images during treatment. Instead of directly using the heterogeneous transit photon fluence measured by the EPID, this method reconstructed the incident beam fluence based on the MLC apertures measured by the EPID and the delivered MU recorded by the linac. To account for the time-dependent-geometry, the incident fluence distributions were sorted into their corresponding phases based on the tumor motion pattern detected by the EPID and accumulated as the incident fluence map for each phase. Together with 4D-CT, it was then used for Monte Carlo dose calculation. Deformable registration was performed to sum up the phase doses for treatment assessment. The feasibility of using the transit EPID images for incident fluence reconstruction was evaluated against EPID in-air measurements. The accuracy of 3D- and 4D-dose reconstruction was validated by a motordriven cylindrical diode array for six clinical SBRT plans. The average difference between the measured and reconstructed fluence maps is within 0.16%. The reconstructed 3D-dose shows 1.4% agreement in the CAX-dose and >98.5% gamma-passing-rate (2%/2mm) in the peripheral-dose. A distorted dose distribution is observed in the measurement for the moving ArcCheck-phantom. The comparison between the measured and the reconstructed 4D-dose without considering interplay fails the gammaevaluation (59%-88.9% gamma-passing-rate). In contrast, when the interplay is considered, the dose distortion phenomena is successfully represented in the reconstructed dose (>97.6% gamma-passing-rate). The experimental validation demonstrates that the proposed

  3. Validity of visual analog scales for assessing psychological states in patients with chronic neck pain. Journal of Musculoskeletal pain

    OpenAIRE

    Dimitriadis, Zacharias; Strimpakos, Nikolaos; Kapreli, Eleni; Oldham, Jacqueline

    2016-01-01

    Objectives: Examination of visual analog scale’s [VAS] validity for assessing psychological states in patients with chronic neck pain.Methods: Forty-five patients with chronic neck pain completed the Hospital Anxiety and Depression Scale, Tampa Scale for Kinesiophobia, and Pain Catastrophizing Scale. Anxiety, depression, kinesiophobia, and catastrophizing were additionally assessed by using a VAS for each.Results: Only the anxiety VAS could correlate high enough with its corresponding questio...

  4. Visualization of inner ear dysplasias in patients with sensorineural hearing loss. High-resolution MR imaging and volume-rendered reconstructions

    Energy Technology Data Exchange (ETDEWEB)

    Klingebiel, R.; Bockmuehl, U. [Charite CM, Humboldt Univ., Berlin (Germany). Dept. of Radiology; Werbs, M. [Charite CM, Humboldt Univ., Berlin (Germany). ENT Dept.; Freigang, B. [O. von Guericke Univ., Magdeburg (Germany). ENT Dept.; Vorwerk, W. [St. Salvator Krankenhaus, Halberstadt (Germany). ENT Dept.; Thieme, N.; Lehmann, R. [Charite CM, Humboldt Univ., Berlin (Germany). Dept. of Radiology

    2001-11-01

    Purpose: We evaluated a data acquisition and post-processing protocol for inner ear (IE) assessment by MR imaging in patients, suffering from various labyrinth malformations. Material and Methods: MR IE studies of 158 consecutive patients (316 IEs) suffering from sensorineural hearing loss without evidence of an acoustic neurinoma were reviewed for pathologies of the IE and internal acoustic meatus. High-resolution MR data of all abnormal IE studies (n=45) were post-processed to previously standardized 3D volume rendered (VR) reconstructions. Results: In 9 patients (5.7%) the following IE dysplasias were detected: malformation of the cochlea (6 IEs), vestibulum (4 IEs), semicircular canals (12 IEs) and vestibular aqueduct/endolymphatic sac (10 IEs). One patient showed evidence of an aplasia of the vestibulocochlear nerve. In 4 patients multiple IE dysplasias were encountered. Comprehensive 3D visualization of all labyrinthine dysplasias was achieved by the use of two VR reconstructions. The overall time for bilateral IE assessment amounted to 30-35 min. Conclusion: The imaging protocol allows for rapid and comprehensive visualization of various IE dysplasias, based on a limited number of VR reconstructions.

  5. Visual analogue scale foot and ankle: validity and reliability of Thai version of the new outcome score in subjective form.

    Science.gov (United States)

    Angthong, Chayanin; Chernchujit, Bancha; Suntharapa, Thongchai; Harnroongroj, Thossart

    2011-08-01

    Nowadays, measuring score in the form of subjective questionnaires is the important tool for clinical evaluation of the foot and ankle-related problems. VisualAnalogue Scale-Foot and Ankle (VAS-FA) is the newly developed subjective questionnaire, which has sufficiency of validity and reliability from a previous study Translate the original English version of VAS-FA into the Thai version and evaluate the validity and reliability of Thai VAS-FA in patients with foot and ankle-related problems. According to the forward-backward translation protocol, original VAS-FA was translated into the Thai version. Thai VAS-FA and validated Thai Short Form-36 (SF-36) questionnaires were distributed to 42 Thai patients to complete. For validation, Thai VAS-FA scores were correlated with SF-36 scores. For reliability, the test-retest reliability and internal consistency were analyzed. Thai VAS-FA score demonstrated the sufficient correlations with physical functioning (PF), role physical (RP), bodily pain (BP) domains, and total score of SF-36 (statistically significant with p 0.5 values). The result of reliability revealed highly intra-class correlation coefficient as 0.995 from test-retest study. The internal consistency was excellent with Cronbach alpha: 0.995. The original VAS-FA score is a well-validated, subjective, visual-analogue-scale based outcome score. The Thai version of VAS-FA form maintained the validity and reliability of the original version. This newly translated-validated score can be distributed for the evaluation of the functions, symptoms, and limitation of activities in Thai patients with foot and ankle problems.

  6. Validity and Reliability of Dynamic Visual Acuity (DVA) Measurement During Walking

    Science.gov (United States)

    Deshpande, Nandini; Peters, Brian T.; Bloomberg, Jacob J.

    2014-01-01

    DVA is primarily subserved by the vestibulo-ocular reflex mechanism. Individuals with vestibular hypofunction commonly experience highly debilitating illusory movement or blurring of visual images during daily activities possibly, due to impaired DVA. Even without pathologies, gradual age-related morphological deterioration is evident in all components of the vestibular system. We examined the construct validity to detect age-related differences and test-retest reliability of DVA measurements performed during walking. METHODS: Healthy adults were recruited into 3 groups: 1. young (20-39years, n=18), 2. middle-aged (40-59years, n=14), and 3. older adults (60-80years, n=15). Randomly selected seven participants from each group (n=21) participated in retesting. Participants were excluded if they had a history of vestibular or neuromuscular pathologies, dizziness/vertigo or >1 falls in the past year. Older persons with MMSE scores DVA was measured while walking on a treadmill at 0.8 m/s, 1.0 m/s and 1.2 m/s speeds. The walking speeds chosen represent a range of slow to moderate walking speeds for adult life span in participants who have no current mobility problems. The monitor that displayed Landolt 'C' optotypes was placed at 50 cm from the eyes for nearDVA (primary compensation by otolith organs) and at 3.0 m for farDVA (primary compensation by semicircular canals). A mixed factor ANOVA (age group x speed) was performed separately for the Near and FarDVA for detecting group differences. Intraclass correlation coefficients (ICCs) were calculated for each condition to determine test-retest reliability. RESULTS: The three age groups were not different in their height, weight and normal walking speed (p>0.05). The post hoc analyses for DVA measurements demonstrated that each group was significantly different from the other two groups for Near as well as FarDVA (pDVA between the three age groups were detected by using both Near and FarDVA protocols irrespective of the

  7. Preliminary results using a newly developed projection method to visualize vascular anatomy prior to DIEP flap breast reconstruction

    NARCIS (Netherlands)

    Hummelink, S.L.; Hameeteman, M.; Hoogeveen, Y.L.; Slump, C.H.; Ulrich, D.J.O.; Schultze Kool, L.J.

    2015-01-01

    INTRODUCTION: In a deep inferior epigastric perforator (DIEP) flap breast reconstruction, computed tomography angiography (CTA) is currently considered as the gold standard in preoperative imaging for this procedure. Unidirectional Doppler ultrasound (US) is frequently used; however, this method

  8. Preliminary results using a newly developed projection method to visualize vascular anatomy prior to DIEP flap breast reconstruction

    NARCIS (Netherlands)

    Hummelink, S.; Hofer, S.; Hameeteman, M.; Hoogeveen, Y.; Slump, Cornelis H.; Ulrich, D.J.O.; Schultze Kool, L.J.

    Introduction: In a deep inferior epigastric perforator (DIEP) flap breast reconstruction, computed tomography angiography (CTA) is currently considered as the gold standard in preoperative imaging for this procedure. Unidirectional Doppler ultrasound (US) is frequently used; however, this method

  9. Validation of Visually Observed Waves with the Recorded Waves on the Southwest Coast of India

    Science.gov (United States)

    Abdulla, P. K.; James, E. J.

    2017-11-01

    The wave climate, pre-requisite information for planning and design of coastal engineering structures, can be obtained by different methods. Coastal protection works require wave climate in the nearshore region; deployment of wave sensors and visual observation of the waves from the shore are among the methods that can be adopted for collecting the wave data. On the southwest coast of India (Kerala), wave data have been collected by visual observation from the shore, at 18 stations located along the entire coastline since 1973. The pressure type wave sensors were installed in the nearshore region at four stations, almost equally spaced along the coast and data acquired for a period of 4 years. Of the four instrument stations, two were located at the visual observation station itself, the third one was about 7 km from the nearest visual observation station and the fourth station midway between two visual observation stations—the distance between the instrument station and the visual observation stations being about 20 km. Study revealed that the visually observed wave parameters are comparable with the wave parameters acquired by the instrument, particularly with respect to the wave height.

  10. Validation of a statistical shape model-based 2D/3D reconstruction method for determination of cup orientation after THA.

    Science.gov (United States)

    Zheng, G; von Recum, J; Nolte, L-P; Grützner, P A; Steppacher, S D; Franke, J

    2012-03-01

    The aim of this study was to validate the accuracy and reproducibility of a statistical shape model-based 2D/3D reconstruction method for determining cup orientation after total hip arthroplasty. With a statistical shape model, this method allows reconstructing a patient-specific 3D-model of the pelvis from a standard AP X-ray radiograph. Cup orientation (inclination and anteversion) is then calculated with respect to the anterior pelvic plane that is derived from the reconstructed model. The validation study was conducted retrospectively on datasets of 29 patients (31 hips). Among them, there were 15 men (15 hips) and 14 women (16 hips). The average age of the patients was 69.4±8.5 (49-82) years. Each dataset has one postoperative X-ray radiograph and one postoperative CT scan. The postoperative CT scan for each patient was used to establish the ground truth for the cup orientation. The cup anteversion and inclination that were calculated from the 2D/3D reconstruction method were compared to the associated ground truth. To validate reproducibility and reliability, two observers performed measurements for each dataset twice in order to measure the reproducibility and the reliability of the 2D/3D reconstruction method. Our validation study demonstrated a mean accuracy of 0.4 ± 1.8° (-2.6° to 3.3°) for inclination and a mean accuracy of 0.6±1.5° (-2.0° to 3.9°) for anteversion. Through the Bland-Altman analysis, no systematic errors in accuracy were detected. The method showed very good consistency for both parameters. Our validation results demonstrate that the statistical shape model-based 2D/3D reconstruction-based method is an accurate, consistent, and reproducible technique to measure cup orientation from postoperative X-ray radiographs. The best results were achieved with radiographs including the bilateral anterior superior iliac spines and the cranial part of non-fractured pelvises.

  11. Task-Difficulty Homeostasis in Car Following Models: Experimental Validation Using Self-Paced Visual Occlusion

    National Research Council Canada - National Science Library

    Pekkanen, Jami; Lappi, Otto; Itkonen, Teemu H; Summala, Heikki

    2017-01-01

    ...) model, by dynamically changing driving parameters as function of driver capability. We examined assumptions of these models experimentally using a self-paced visual occlusion paradigm in a simulated car following task...

  12. The PedsQL™ Present Functioning Visual Analogue Scales: preliminary reliability and validity

    OpenAIRE

    Varni James W; Burwinkle Tasha M; Eisen Sarajane; Sherman Sandra A

    2006-01-01

    Abstract Background The PedsQL™ Present Functioning Visual Analogue Scales (PedsQL™ VAS) were designed as an ecological momentary assessment (EMA) instrument to rapidly measure present or at-the-moment functioning in children and adolescents. The PedsQL™ VAS assess child self-report and parent-proxy report of anxiety, sadness, anger, worry, fatigue, and pain utilizing six developmentally appropriate visual analogue scales based on the well-established Varni/Thompson Pediatric Pain Questionnai...

  13. The reliability and validity study of the Kinesthetic and Visual Imagery Questionnaire in individuals with Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Yousef Moghadas Tabrizi

    2013-12-01

    Full Text Available OBJECTIVE: Motor imagery (MI has been recently considered as an adjunct to physical rehabilitation in patients with multiple sclerosis (MS. It is necessary to assess MI abilities and benefits in patients with MS by using a reliable tool. The Kinesthetic and Visual Imagery Questionnaire (KVIQ was recently developed to assess MI ability in patients with stroke and other disabilities. Considering the different underlying pathologies, the present study aimed to examine the validity and reliability of the KVIQ in MS patients. METHOD: Fifteen MS patients were assessed using the KVIQ in 2 sessions (5-14days apart by the same examiner. In the second session, the participants also completed a revised MI questionnaire (MIQ-R as the gold standard. Intra-class correlation coefficients (ICCs were measured to determine test-retest reliability. Spearman's correlation analysis was performed to assess concurrent validity with the MIQ-R. Furthermore, the internal consistency (Cronbach's alpha and factorial structure of the KVIQ were studied. RESULTS: The test-retest reliability for the KVIQ was good (ICCs: total KVIQ=0.89, visual KVIQ=0.85, and kinesthetic KVIQ=0.93, and the concurrent validity between the KVIQ and MIQ-R was good (r=0.79. The KVIQ had good internal consistency, with high Cronbach's alpha (alpha=0.84. Factorial analysis showed the bi-factorial structure of the KVIQ, which was explained by visual=57.6% and kinesthetic=32.4%. CONCLUSIONS: The results of the present study revealed that the KVIQ is a valid and reliable tool for assessing MI in MS patients.

  14. Assessing repeatability and validity of a visual analogue scale questionnaire for use in assessing pain and lameness in dogs.

    Science.gov (United States)

    Hudson, Jonathan T; Slater, Margaret R; Taylor, Lathrop; Scott, H Morgan; Kerwin, Sharon C

    2004-12-01

    To develop a visual analogue scale (VAS) questionnaire that is repeatable and valid for use in assessing pain and lameness in dogs. 48 client-owned dogs with mild to moderate lameness. The dogs were from 3 studies conducted during a 3-year period. Of the 48 dogs, 19 were used in repeatability assessment, 48 were used in principal component analysis, and 44 were used in model selection procedures and validity testing. A test-retest measure of repeatability was conducted on dogs with a change of validity of the questionnaire. 19 of 39 questions were found to be repeatable on the basis of a Spearman rank-correlation cut point of > 0.6. Model selection procedures resulted in 3 overlapping subsets of questions that were considered valid representations of the forces measured (vertical peak, vertical impulse, and propulsion peak). Each reduced model fit the data as well as the full model. The VAS questionnaire was repeatable and valid for use in assessing the degree of mild to moderate lameness in dogs.

  15. Reliable categorisation of visual scoring of coronary artery calcification on low-dose CT for lung cancer screening: validation with the standard Agatston score

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yi-Luan; Wu, Fu-Zong; Wang, Yen-Chi [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung 813 (China); National Yang Ming University, Faculty of Medicine, School of Medicine, Taipei (China); Ju, Yu-Jeng [National Taiwan University, Department of Psychology, Taipei (China); Mar, Guang-Yuan [Kaohsiung Veterans General Hospital, Division of Cardiology, Department of Medicine, Kaohsiung 813 (China); Chuo, Chiung-Chen [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung 813 (China); Lin, Huey-Shyan [Fooyin University, School of Nursing, Kaohsiung (China); Wu, Ming-Ting [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung 813 (China); National Yang Ming University, Faculty of Medicine, School of Medicine, Taipei (China); National Yang Ming University, Institute of Clinical Medicine, Taipei (China)

    2013-05-15

    To validate the reliability of the visual coronary artery calcification score (VCACS) on low-dose CT (LDCT) for concurrent screening of CAC and lung cancer. We enrolled 401 subjects receiving LDCT for lung cancer screening and ECG-gated CT for the Agatston score (AS). LDCT was reconstructed with 3- and 5-mm slice thickness (LDCT-3mm and LDCT-5mm respectively) for VCACS to obtain VCACS-3mm and VCACS-5mm respectively. After a training session comprising 32 cases, two observers performed four-scale VCACS (absent, mild, moderate, severe) of 369 data sets independently, the results were compared with four-scale AS (0, 1-100, 101-400, >400). CACs were present in 39.6 % (146/369) of subjects. The sensitivity of VCACS-3mm was higher than for VCACS-5mm (83.6 % versus 74.0 %). The median of AS of the 24 false-negative cases in VCACS-3mm was 2.3 (range 1.1-21.1). The false-negative rate for detecting AS {>=} 10 on LDCT-3mm was 1.9 %. VCACS-3mm had higher concordance with AS than VCACS-5mm (k = 0.813 versus k = 0.685). An extended test of VCACS-3mm for four junior observers showed high inter-observer reliability (intra-class correlation = 0.90) and good concordance with AS (k = 0.662-0.747). This study validated the reliability of VCACS on LDCT for lung cancer screening and showed that LDCT-3mm was more feasible than LDCT-5mm for CAD risk stratification. (orig.)

  16. A visual analogue scale for assessment of the impact of rheumatoid arthritis in the hand: validity and repeatability.

    Science.gov (United States)

    Massy-Westropp, Nicoa; Ahern, Michael; Krishnan, Jegan

    2005-01-01

    A visual analogue scale was developed by French rheumatologists to measure the impact caused by rheumatoid arthritis of the hand (VAS-Hand). This article reports the use of the measure. First, the validity of the VAS-Hand was investigated by interviewing patients to understand how they interpreted and answered these questions. Second, the measure was compared with disability, pain, and impairment measures to determine whether it provided additional information. Finally, the repeatability of the measure was defined as within 1.5 points out of ten. The visual analogue scale of handicap from rheumatoid arthritis of the hand provides different information than do health status or disability questionnaires, or strength and motion assessment. The responsiveness of the VAS-Hand is under investigation in a longitudinal study.

  17. Improved visualization of collateral ligaments of the ankle: multiplanar reconstructions based on standard 2D turbo spin-echo MR images

    Energy Technology Data Exchange (ETDEWEB)

    Duc, Sylvain R.; Mengiardi, Bernard; Pfirrmann, Christian W.A.; Hodler, Juerg; Zanetti, Marco [University Hospital, Balgrist, From the Departments of Radiology, Zurich (Switzerland)

    2007-05-15

    The purpose of the study was to evaluate the visualization of the collateral ankle ligaments on multiplanar reconstructions (MPR) based on standard 2D turbo spin-echo images. Coronal and axial T2-weighted turbo spin-echo and MPR angled parallel to the course of the ligaments of 15 asymptomatic and 15 symptomatic ankles were separately analyzed by two musculoskeletal radiologists. Image quality was assessed in the asymptomatic ankles qualitatively. In the symptomatic ankles interobserver agreement and reader confidence was determined for each ligament. On MPR the tibionavicular and calcaneofibular ligaments were more commonly demonstrated on a single image than on standard MR images (reader 1: 13 versus 0, P=0.002; reader 2: 14 versus 1, P=0.001 and reader 1: 13 versus 2, P=0.001; reader 2: 14 versus 0, P<0.001). The tibionavicular ligament was considered to be better delineated on MPR by reader 1 (12 versus 3, P=0.031). In the symptomatic ankles, reader confidence was greater with MPR for all ligaments except for the tibiocalcanear ligament (both readers) and the anterior and posterior talofibular ligaments (for reader 2). Interobserver agreement was increased with MPR for the tibionavicular ligament. Multiplanar reconstructions of 2D turbo spin-echo images improve the visualization of the tibionavicular and calcaneofibular ligaments and strengthen diagnostic confidence for these ligaments. (orig.)

  18. Validation of a visual analogue score (LRTI-VAS) in non-CF bronchiectasis

    NARCIS (Netherlands)

    Altenburg, Josje; Wortel, Kim; de Graaff, Casper S.; van der Werf, Tjip S.; Boersma, Wim G.

    Background and AimQuality of life in patients with non-cystic fibrosis (non-CF) bronchiectasis is largely defined by respiratory symptoms. To date, no disease-specific tool for symptom measurement in this patient group was available. We developed the lower respiratory tract infections - visual

  19. The validation of the visual analogue scale for patient satisfaction after total hip arthroplasty.

    NARCIS (Netherlands)

    Brokelman, R.B.G.; Haverkamp, D.; Loon, C. van; Hol, A.; Kampen, A. van; Veth, R.P.H.

    2012-01-01

    INTRODUCTION: Patient satisfaction becomes more important in our modern health care system. The assessment of satisfaction is difficult because it is a multifactorial item for which no golden standard exists. One of the potential methods of measuring satisfaction is by using the well-known visual

  20. Validation of an efficient visual method for estimating leaf area index ...

    African Journals Online (AJOL)

    This study aimed to evaluate the accuracy and applicability of a visual method for estimating LAI in clonal Eucalyptus grandis × E. urophylla plantations and to compare it with hemispherical photography, ceptometer and LAI-2000® estimates. Destructive sampling for direct determination of the actual LAI was performed in ...

  1. Reliability and Validity of the TGMD-2 in Primary-School-Age Children With Visual Impairments

    NARCIS (Netherlands)

    Houwen, Suzanne; Hartman, Esther; Jonker, Laura; Visscher, Chris

    This study examines the psychometric properties of the Test of Gross Motor Development-2 (TGMD-2) in children with visual impairments (VI). Seventy-five children aged between 6 and 12 years with VI completed the TGMD-2 and the Movement Assessment Battery for Children (Movement ABC). The internal

  2. Reliability and Validity of the TGMD-2 in Primary-School-Age Children with Visual Impairments

    Science.gov (United States)

    Houwen, Suzanne; Hartman, Esther; Jonker, Laura; Visscher, Chris

    2010-01-01

    This study examines the psychometric properties of the Test of Gross Motor Development-2 (TGMD-2) in children with visual impairments (VI). Seventy-five children aged between 6 and 12 years with VI completed the TGMD-2 and the Movement Assessment Battery for Children (Movement ABC). The internal consistency of the TGMD-2 was found to be high…

  3. Reconstructive endovascular treatment of vertebral artery dissecting aneurysms with the Low-profile Visualized Intraluminal Support (LVIS) device

    National Research Council Canada - National Science Library

    Chuan-Chuan Wang; Yi-Bin Fang; Ping Zhang; Xuan Zhu; Bo Hong; Yi Xu; Jian-Min Liu; Qing-Hai Huang

    2017-01-01

    Introduction The Low-profile Visualized Intraluminal Support (LVIS) device is a new generation of self-expanding braided stent recently introduced in China for stent assisted coiling of intracranial aneurysms...

  4. Determination of plate waste in primary school lunches by weighing and visual estimation methods: a validation study.

    Science.gov (United States)

    Liz Martins, Margarida; Cunha, Luís M; Rodrigues, Sara S P; Rocha, Ada

    2014-08-01

    The aim of this study was to validate the visual estimation method for aggregated plate waste of main dish at Portuguese primary school canteens. For this purpose plate waste at school lunch was measured for 505 individual servings, using weighing individual servings and plate waste and visual estimation method by a 6-point scale, as developed by Comstock et al. (1981). A high variability of initial serving weights was found with serving sizes ranging from 88.9 to 283.3g and with a coefficient of variation ranging from 5.5% to 24.7%. Mean plate waste was 27.5% according to the weighing method. There was a significant bias in the conversion of the visual waste estimations to actual waste, being overestimated by an average of 8.0 g (ranging from -12.9 g to 41.4 g). According to Bland and Altman plot, the mean difference between methods was of 8.0 g and the amplitude interval was 102.6g. The study showed that the visual estimation method is not as accurate as the weighing method in assessing nonselective aggregated plate waste at primary school canteens. Our findings are thus very important on considering plate waste assessment, since the wide variation on initial servings introduces a relevant bias when considering standard portions or a random sample of initial servings. Although, greater convenience, time-saving and the possibility to monitor plate waste of large groups, make the visual estimation method an important method to assess plate waste at school canteens, these results highlighted the need of portions standardization and control of initial servings to allow for its use. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Determination of left ventricular mass and circumferential wall thickness by three-dimensional reconstruction: in vitro validation of a new method that uses a multiplane transesophageal transducer.

    Science.gov (United States)

    Kühl, H P; Franke, A; Frielingsdorf, J; Flaskamp, C; Krebs, W; Flachskampf, F A; Hanrath, P

    1997-03-01

    Elevated left ventricular mass and increased wall thickness have important prognostic implications in clinical medicine. However, these parameters have been incompletely characterized by one- and two-dimensional echocardiography. Therefore this study was performed to validate in vitro measurement of left ventricular mass and circumferential wall thickness with a multiplane transesophageal transducer and three-dimensional reconstruction. Results for mass measurements were also compared with a standard method for the determination of left ventricular mass, the Penn convention. Fourteen necropsied left ventricles were scanned in a water bath by a volume-rendering, three-dimensional reconstruction system. There was an excellent correlation and high agreement for determination of three-dimensional left ventricular mass (r = 0.98; standard error of the estimate [SEE] = 9.6 gm; y = 1.02x + 0.46) and wall thickness (r = 0.93; SEE = 1.4 mm; y = 0.95x + 1.64) compared with anatomic measurements. Left ventricular mass by a simulated Penn convention revealed a lower correlation and larger error compared with three-dimensional measurements (r = 0.72; SEE = 42.8 gm; y = 1.01x + 9.61). Therefore determination of left ventricular mass by three-dimensional reconstruction was validated in vitro and was superior to one-dimensional echocardiographic methods.

  6. Reliability and validity of the Psoriasis Itch Visual Analog Scale in psoriasis vulgaris.

    Science.gov (United States)

    Pedersen, Claus Bang; McHorney, Colleen A; Larsen, Lotte Seiding; Lophaven, Katja Wendicke; Moeller, Anders Holmen; Reaney, Matthew

    2017-05-01

    The single-item Psoriasis Itch VAS was developed to measure itch intensity within the last 24 hours in psoriasis vulgaris to assess treatment benefit. Its psychometric properties were explored in two trials. Data from two randomized, parallel-group phase 3 trials with subjects suffering from psoriasis vulgaris on the body (n = 426, 463) were analyzed. Cross-sectional distributional properties and construct validity of the Psoriasis Itch VAS as well as longitudinal test-retest reliability and sensitivity to change of the Psoriasis Itch VAS were investigated. All statistical tests were two-tailed. Across both trials, acceptable distributional properties were observed. Convergent-validity correlations between the Psoriasis Itch VAS and other patient-reported and clinician-reported outcomes provided strong endorsement for construct validity as did tests of known-groups validity. Longitudinal measurement properties, involving test-retest reliability and sensitivity to change, also offered evidence for the measurement integrity of the Psoriasis Itch VAS. Results from the assessment of validity, reliability, and sensitivity to change support the use of the Psoriasis Itch VAS to measure itch intensity in psoriasis vulgaris. Data from two trials provided evidence that the Psoriasis Itch VAS is well-defined and reliable for measuring itch in psoriasis vulgaris to assess treatment benefit (i.e. therapeutic response).

  7. Task-Difficulty Homeostasis in Car Following Models: Experimental Validation Using Self-Paced Visual Occlusion.

    Science.gov (United States)

    Pekkanen, Jami; Lappi, Otto; Itkonen, Teemu H; Summala, Heikki

    2017-01-01

    Car following (CF) models used in traffic engineering are often criticized for not incorporating "human factors" well known to affect driving. Some recent work has addressed this by augmenting the CF models with the Task-Capability Interface (TCI) model, by dynamically changing driving parameters as function of driver capability. We examined assumptions of these models experimentally using a self-paced visual occlusion paradigm in a simulated car following task. The results show strong, approximately one-to-one, correspondence between occlusion duration and increase in time headway. The correspondence was found between subjects and within subjects, on aggregate and individual sample level. The long time scale aggregate results support TCI-CF models that assume a linear increase in time headway in response to increased distraction. The short time scale individual sample level results suggest that drivers also adapt their visual sampling in response to transient changes in time headway, a mechanism which isn't incorporated in the current models.

  8. A validated methodology for the 3D reconstruction of cochlea geometries using human microCT images

    Science.gov (United States)

    Sakellarios, A. I.; Tachos, N. S.; Rigas, G.; Bibas, T.; Ni, G.; Böhnke, F.; Fotiadis, D. I.

    2017-05-01

    Accurate reconstruction of the inner ear is a prerequisite for the modelling and understanding of the inner ear mechanics. In this study, we present a semi-automated methodology for accurate reconstruction of the major inner ear structures (scalae, basilar membrane, stapes and semicircular canals). For this purpose, high resolution microCT images of a human specimen were used. The segmentation methodology is based on an iterative level set algorithm which provides the borders of the structures of interest. An enhanced coupled level set method which allows the simultaneous multiple image labeling without any overlapping regions has been developed for this purpose. The marching cube algorithm was applied in order to extract the surface from the segmented volume. The reconstructed geometries are then post-processed to improve the basilar membrane geometry to realistically represent physiologic dimensions. The final reconstructed model is compared to the available data from the literature. The results show that our generated inner ear structures are in good agreement with the published ones, while our approach is the most realistic in terms of the basilar membrane thickness and width reconstruction.

  9. LATUX: An Iterative Workflow for Designing, Validating, and Deploying Learning Analytics Visualizations

    Science.gov (United States)

    Martinez-Maldonado, Roberto; Pardo, Abelardo; Mirriahi, Negin; Yacef, Kalina; Kay, Judy; Clayphan, Andrew

    2015-01-01

    Designing, validating, and deploying learning analytics tools for instructors or students is a challenge that requires techniques and methods from different disciplines, such as software engineering, human-computer interaction, computer graphics, educational design, and psychology. Whilst each has established its own design methodologies, we now…

  10. Validity and Interrater Reliability of the Visual Quarter-Waste Method for Assessing Food Waste in Middle School and High School Cafeteria Settings.

    Science.gov (United States)

    Getts, Katherine M; Quinn, Emilee L; Johnson, Donna B; Otten, Jennifer J

    2017-11-01

    Measuring food waste (ie, plate waste) in school cafeterias is an important tool to evaluate the effectiveness of school nutrition policies and interventions aimed at increasing consumption of healthier meals. Visual assessment methods are frequently applied in plate waste studies because they are more convenient than weighing. The visual quarter-waste method has become a common tool in studies of school meal waste and consumption, but previous studies of its validity and reliability have used correlation coefficients, which measure association but not necessarily agreement. The aims of this study were to determine, using a statistic measuring interrater agreement, whether the visual quarter-waste method is valid and reliable for assessing food waste in a school cafeteria setting when compared with the gold standard of weighed plate waste. To evaluate validity, researchers used the visual quarter-waste method and weighed food waste from 748 trays at four middle schools and five high schools in one school district in Washington State during May 2014. To assess interrater reliability, researcher pairs independently assessed 59 of the same trays using the visual quarter-waste method. Both validity and reliability were assessed using a weighted κ coefficient. For validity, as compared with the measured weight, 45% of foods assessed using the visual quarter-waste method were in almost perfect agreement, 42% of foods were in substantial agreement, 10% were in moderate agreement, and 3% were in slight agreement. For interrater reliability between pairs of visual assessors, 46% of foods were in perfect agreement, 31% were in almost perfect agreement, 15% were in substantial agreement, and 8% were in moderate agreement. These results suggest that the visual quarter-waste method is a valid and reliable tool for measuring plate waste in school cafeteria settings. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  11. Visualization of vasculature using a hand-held photoacoustic probe: phantom and in vivo validation

    Science.gov (United States)

    Heres, H. Maarten; Arabul, Mustafa Umit; Rutten, Marcel C. M.; Van de Vosse, Frans N.; Lopata, Richard G. P.

    2017-04-01

    Assessment of microvasculature and tissue perfusion can provide diagnostic information on local or systemic diseases. Photoacoustic (PA) imaging has strong clinical potential because of its sensitivity to hemoglobin. We used a hand-held PA probe with integrated diode lasers and examined its feasibility and validity in the detection of increasing blood volume and (sub) dermal vascularization. Blood volume detection was tested in custom-made perfusion phantoms. Results showed that an increase of blood volume in a physiological range of 1.3% to 5.4% could be detected. The results were validated with power Doppler sonography. Using a motorized scanning setup, areas of the skin were imaged at relatively short scanning times (epidermis and submillimeter vasculature up to depth of 5 mm. The geometries of imaged vasculature were validated with segmentation of the vasculature in high-frequency ultrasound imaging. This study proves the feasibility of PA imaging in its current implementation for the detection of perfusion-related parameters in skin and subdermal tissue and underlines its potential as a diagnostic tool in vascular or dermal pathologies.

  12. RF Tomography in Free Space: Experimental Validation of the Forward Model and an Inversion Algorithm Based on the Algebraic Reconstruction Technique

    Directory of Open Access Journals (Sweden)

    V. Picco

    2013-01-01

    Full Text Available Radio-frequency tomography was originally proposed to image underground cavities. Its flexible forward model can be used in free-space by choosing an appropriate dyadic Green's function and can be translated in the microwave domain. Experimental data are used to validate a novel inversion scheme, based on the algebraic reconstruction technique. The proposed method is improved by introducing physical bounds on the solution returned. As a result, the images of the dielectric permittivity profiles obtained are superior in quality to the ones obtained using classical regularization approaches such as the truncated singular value decomposition. The results from three experimental case studies are presented and discussed.

  13. Calibration, validation and application of foraminiferal carbonate based proxies. Reconstructing temperature, salinity and sea water Mg/Ca

    NARCIS (Netherlands)

    Wit, J.C.

    2012-01-01

    The chemistry of the calcite test of foraminifera is often relating to the environmental conditions under which they lived. These so-called proxy-relations are regularly used as a tool to reconstruct past climates. Accuracy of these proxies is, however, often limited due to uncertainties or absence

  14. Development and validation of a visual body condition scoring system for dairy goats with picture-based training.

    Science.gov (United States)

    Vieira, A; Brandão, S; Monteiro, A; Ajuda, I; Stilwell, G

    2015-09-01

    Body condition scoring (BCS) is the most widely used method to assess changes in body fat reserves, which reflects its high potential to be included in on-farm welfare assessment protocols. Currently used scoring systems in dairy goats require animal restraint for body palpation. In this study, the Animal Welfare Indicators project (AWIN) proposes to overcome this constraint by developing a scoring system based only on visual assessment. The AWIN visual body condition scoring system highlights representative animals from 3 categories: very thin, normal, and very fat, and was built from data sets with photographs of animals scored by a commonly used 6-point scoring system that requires palpation in 2 anatomical regions. Development of the AWIN scoring system required 3 steps: (1) identification and validation of a body region of interest; (2) sketching the region from photographs; and (3) creation of training material. The scoring system's reliability was statistically confirmed. An initial study identified features in the rump region from which we could compute a set of body measurements (i.e., measures based on anatomical references of the rump region) that showed a strong correlation with the assigned BCS. To validate the result, we collected a final data set from 171 goats. To account for variability in animal size and camera position, we mapped a subset of features to a standard template and aligned all the rump images before computing the body measurements. Scientific illustrations were created from the aligned images of animals identified as representative of each category to increase clarity and reproducibility. For training material, we created sketches representing the threshold between consecutive categories. Finally, we conducted 2 field reliability studies. In the first test, no training was given to 4 observers, whereas in the second, training using the threshold images was delivered to the same observers. In the first experiment, interobserver results

  15. 3D-Reconstructions and Virtual 4D-Visualization to Study Metamorphic Brain Development in the Sphinx Moth Manduca Sexta.

    Science.gov (United States)

    Huetteroth, Wolf; El Jundi, Basil; El Jundi, Sirri; Schachtner, Joachim

    2010-01-01

    DURING METAMORPHOSIS, THE TRANSITION FROM THE LARVA TO THE ADULT, THE INSECT BRAIN UNDERGOES CONSIDERABLE REMODELING: new neurons are integrated while larval neurons are remodeled or eliminated. One well acknowledged model to study metamorphic brain development is the sphinx moth Manduca sexta. To further understand mechanisms involved in the metamorphic transition of the brain we generated a 3D standard brain based on selected brain areas of adult females and 3D reconstructed the same areas during defined stages of pupal development. Selected brain areas include for example mushroom bodies, central complex, antennal- and optic lobes. With this approach we eventually want to quantify developmental changes in neuropilar architecture, but also quantify changes in the neuronal complement and monitor the development of selected neuronal populations. Furthermore, we used a modeling software (Cinema 4D) to create a virtual 4D brain, morphing through its developmental stages. Thus the didactical advantages of 3D visualization are expanded to better comprehend complex processes of neuropil formation and remodeling during development. To obtain datasets of the M. sexta brain areas, we stained whole brains with an antiserum against the synaptic vesicle protein synapsin. Such labeled brains were then scanned with a confocal laser scanning microscope and selected neuropils were reconstructed with the 3D software AMIRA 4.1.

  16. 3D-reconstructions and virtual 4D-visualization to study metamorphic brain development in the sphinx moth Manduca sexta

    Directory of Open Access Journals (Sweden)

    Wolf Huetteroth

    2010-03-01

    Full Text Available During metamorphosis, the transition from the larva to the adult, the insect brain undergoes considerable remodeling: New neurons are integrated while larval neurons are remodeled or eliminated. One well acknowledged model to study metamorphic brain development is the sphinx moth Manduca sexta. To further understand mechanisms involved in the metamorphic transition of the brain we generated a 3D standard brain based on selected brain areas of adult females and 3D reconstructed the same areas during defined stages of pupal development. Selected brain areas include for example mushroom bodies, central complex, antennal- and optic lobes. With this approach we eventually want to quantify developmental changes in neuropilar architecture, but also quantify changes in the neuronal complement and monitor the development of selected neuronal populations. Furthermore, we used a modeling software (Cinema 4D to create a virtual 4D brain, morphing through its developmental stages. Thus the didactical advantages of 3D visualization are expanded to better comprehend complex processes of neuropil formation and remodeling during development. To obtain datasets of the M. sexta brain areas, we stained whole brains with an antiserum against the synaptic vesicle protein synapsin. Such labeled brains were then scanned with a confocal laser scanning microscope and selected neuropils were reconstructed with the 3D software AMIRA 4.1.

  17. Visual Attention Allocation Between Robotic Arm and Environmental Process Control: Validating the STOM Task Switching Model

    Science.gov (United States)

    Wickens, Christopher; Vieanne, Alex; Clegg, Benjamin; Sebok, Angelia; Janes, Jessica

    2015-01-01

    Fifty six participants time shared a spacecraft environmental control system task with a realistic space robotic arm control task in either a manual or highly automated version. The former could suffer minor failures, whose diagnosis and repair were supported by a decision aid. At the end of the experiment this decision aid unexpectedly failed. We measured visual attention allocation and switching between the two tasks, in each of the eight conditions formed by manual-automated arm X expected-unexpected failure X monitoring- failure management. We also used our multi-attribute task switching model, based on task attributes of priority interest, difficulty and salience that were self-rated by participants, to predict allocation. An un-weighted model based on attributes of difficulty, interest and salience accounted for 96 percent of the task allocation variance across the 8 different conditions. Task difficulty served as an attractor, with more difficult tasks increasing the tendency to stay on task.

  18. Testing the validity of wireless EEG for cognitive research with auditory and visual paradigms

    DEFF Research Database (Denmark)

    Weed, Ethan; Kratschmer, Alexandra Regina; Pedersen, Michael Nygaard

    , are available in both Emotiv and Brain Products layouts, so we used these in our analysis. Both MMN and N170 were measured as difference waves (MMN: deviants - standards, N170: faces - houses). Significance was measured with one-sample t-tests at each of the chosen electrodes. The MMN was visible in data......One of the challenges in collecting ERP data is the time-consuming process of fitting caps and prepping electrodes with gel. This can be particularly true when working with clinical populations, where efficiency in data collection is important. Recently gel-free wireless headsets designed for brain...... and smaller cognitive components. To test the feasibility of these headsets for cognitive research, we compared performance of the Emotiv Epoc wireless headset (EM) with Brain Products ActiCAP (BP) active electrodes on two well-studied components: the auditory mismatch negativity (MMN) and the visual face...

  19. Retinal specific measurement of dark-adapted visual function: validation of a modified microperimeter

    Directory of Open Access Journals (Sweden)

    Luong Vy A

    2011-02-01

    Full Text Available Abstract Background Scotopic function is an important marker of many retinal diseases and is increasingly used as an outcome measure in clinical trials, such as those investigating gene therapy for Lebers congenital amaurosis. Scotopic visual function has traditionally been measured using an adapted perimetry system such as the Humphrey field analyser (HFA. However this system does not control for fixation errors or poor fixation stability. Here we evaluate the use of an adapted microperimeter to measure visual function at defined retinal regions under scotopic conditions. Methods A MP-1 microperimeter (Nidek Technologies, Italy was modified by adding a 1 log unit Neutral Density filter and a 530nm shortpass filter within the optical path of the instrument. Stray light was shielded. Fine matrix mapping perimetry was performed on five younger (65 years subjects with no eye disease and good vision. All subjects were fully dark adapted before testing and pupils were dilated with 1% tropicamide. Tests was performed once on the modified MP-1 microperimeter and once using a modified HFA, in a counterbalanced order. Results A foveal scotopic scotoma with a sensitivity reduction of >1 log unit was found using each instrument. In addition, the MP-1 system showed the retinal location of the foveal scotoma. Mean test time was 25 minutes for the MP-1 and 32 minutes for the HFA. Discussion A modified MP-1 microperimeter can be used to measure scotopic retinal function, creating results which are comparable to the modified Humphrey field analyser. Advantages of the MP-1 system include the ability to track the retina through testing, retinal localisation of the scotoma and a faster test time.

  20. Calibration and validation of the Physical Activity Barrier Scale for persons who are blind or visually impaired.

    Science.gov (United States)

    Lee, Miyoung; Zhu, Weimo; Ackley-Holbrook, Elizabeth; Brower, Diana G; McMurray, Bryan

    2014-07-01

    It is critical to employ accurate measures when assessing physical activity (PA) barriers in any subpopulation, yet existing measures are not appropriate for persons with blindness or visual impairment (PBVI) due to a lack of validity or reliability evidence. To develop and calibrate a PA barrier scale for PBVI. An expert panel (n = 3) and 18 PBVI were recruited to establish content validity for a PA barriers subscale; 160 PBVI (96 females) completed the scale along with the Physical Activity Scale for Individuals with Physical Disabilities for calibration. To establish construct-related validity evidence, Confirmative factor analysis (CFA) and Rasch analysis were applied. To investigate internal consistency and reliability, Cronbach's alpha and the reliability coefficient (R) were employed, respectively. Following CFA and Rasch analyses, five items were eliminated due to misfits; reliability coefficients were unchanged upon deletion of these items. The barriers perceived by PBVI to have the most negative impact on PA included "lack of self-discipline" (logit = 1.40) and "lack of motivation" (logit = 1.27). "Too many stairs in the exercise facility" (logit = -1.49) was perceived to have the least impact. The newly-developed scale was found to be a valid and reliable tool for evaluating PA barriers in PBVI. To enhance promotion of health-producing levels of PA in PBVI, practitioners should consider applying this new tool as a precursor to programs aimed at improving PA participation in this group. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Reconstructing glacier-based climates of LGM Europe and Russia – Part 1: Numerical modelling and validation methods

    Directory of Open Access Journals (Sweden)

    R. Allen

    2008-11-01

    Full Text Available The mountain environments of mid-latitude Europe and Arctic Russia contain widespread evidence of Late-Quaternary glaciers that have been attributed to the Last Glacial Maximum (LGM. This glacial-geological record has yet to be used to quantitatively reconstruct the LGM climate of these regions. Here we describe a simple glacier-climate model that can be used to derive regional temperature and precipitation information from a known glacier distribution. The model was tested against the present day distribution of glaciers in Europe. The model is capable of adequately predicting the spatial distribution, snowline and equilibrium line altitude climate of glaciers in the Alps, Scandinavia, Caucasus and Pyrenees Mountains. This verification demonstrated that the model can be used to investigate former climates such as the LGM. Reconstructions of LGM climates from proxy evidence are an important method of assessing retrospective general circulation model (GCM simulations. LGM palaeoclimate reconstructions from glacial-geological evidence would be of particular benefit to investigations in Europe and Russia, where to date only fossil pollen data have been used to assess continental-scale GCM simulations.

  2. Catch-up validation study of an in vitro skin irritation test method based on an open source reconstructed epidermis (phase II).

    Science.gov (United States)

    Groeber, F; Schober, L; Schmid, F F; Traube, A; Kolbus-Hernandez, S; Daton, K; Hoffmann, S; Petersohn, D; Schäfer-Korting, M; Walles, H; Mewes, K R

    2016-10-01

    To replace the Draize skin irritation assay (OECD guideline 404) several test methods based on reconstructed human epidermis (RHE) have been developed and were adopted in the OECD test guideline 439. However, all validated test methods in the guideline are linked to RHE provided by only three companies. Thus, the availability of these test models is dependent on the commercial interest of the producer. To overcome this limitation and thus to increase the accessibility of in vitro skin irritation testing, an open source reconstructed epidermis (OS-REp) was introduced. To demonstrate the capacity of the OS-REp in regulatory risk assessment, a catch-up validation study was performed. The participating laboratories used in-house generated OS-REp to assess the set of 20 reference substances according to the performance standards amending the OECD test guideline 439. Testing was performed under blinded conditions. The within-laboratory reproducibility of 87% and the inter-laboratory reproducibility of 85% prove a high reliability of irritancy testing using the OS-REp protocol. In addition, the prediction capacity was with an accuracy of 80% comparable to previous published RHE based test protocols. Taken together the results indicate that the OS-REp test method can be used as a standalone alternative skin irritation test replacing the OECD test guideline 404. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Visualization Tools and Techniques for Search and Validation of Large Earth Science Spatial-Temporal Metadata Databases

    Science.gov (United States)

    Baskin, W. E.; Herbert, A.; Kusterer, J.

    2014-12-01

    Spatial-temporal metadata databases are critical components of interactive data discovery services for ordering Earth Science datasets. The development staff at the Atmospheric Science Data Center (ASDC) works closely with satellite Earth Science mission teams such as CERES, CALIPSO, TES, MOPITT, and CATS to create and maintain metadata databases that are tailored to the data discovery needs of the Earth Science community. This presentation focuses on the visualization tools and techniques used by the ASDC software development team for data discovery and validation/optimization of spatial-temporal objects in large multi-mission spatial-temporal metadata databases. The following topics will be addressed: Optimizing the level of detail of spatial temporal metadata to provide interactive spatial query performance over a multi-year Earth Science mission Generating appropriately scaled sensor footprint gridded (raster) metadata from Level1 and Level2 Satellite and Aircraft time-series data granules Performance comparison of raster vs vector spatial granule footprint mask queries in large metadata database and a description of the visualization tools used to assist with this analysis

  4. Validation of Catquest-9SF-A Visual Disability Instrument to Evaluate Patient Function After Corneal Transplantation.

    Science.gov (United States)

    Claesson, Margareta; Armitage, W John; Byström, Berit; Montan, Per; Samolov, Branka; Stenvi, Ulf; Lundström, Mats

    2017-09-01

    Catquest-9SF is a 9-item visual disability questionnaire developed for evaluating patient-reported outcome measures after cataract surgery. The aim of this study was to use Rasch analysis to determine the responsiveness of Catquest-9SF for corneal transplant patients. Patients who underwent corneal transplantation primarily to improve vision were included. One group (n = 199) completed the Catquest-9SF questionnaire before corneal transplantation and a second independent group (n = 199) completed the questionnaire 2 years after surgery. All patients were recorded in the Swedish Cornea Registry, which provided clinical and demographic data for the study. Winsteps software v.3.91.0 (Winsteps.com, Beaverton, OR) was used to assess the fit of the Catquest-9SF data to the Rasch model. Rasch analysis showed that Catquest-9SF applied to corneal transplant patients was unidimensional (infit range, 0.73-1.32; outfit range, 0.81-1.35), and therefore, measured a single underlying construct (visual disability). The Rasch model explained 68.5% of raw variance. The response categories of the 9-item questionnaire were ordered, and the category thresholds were well defined. Item difficulty matched the level of patients' ability (0.36 logit difference between the means). Precision in terms of person separation (3.09) and person reliability (0.91) was good. Differential item functioning was notable for only 1 item (satisfaction with vision), which had a differential item functioning contrast of 1.08 logit. Rasch analysis showed that Catquest-9SF is a valid instrument for measuring visual disability in patients who have undergone corneal transplantation primarily to improve vision.

  5. Validity and limitation of manual rotational test to detect impaired visual-vestibular interaction due to cerebellar disorders.

    Science.gov (United States)

    Murai, Norihiko; Funabiki, Kazuo; Naito, Yasushi; Ito, Juichi; Fukuyama, Hidenao

    2005-03-01

    The aim of this study was to investigate validity and limitation of the novel infrared system to record and analyze horizontal visual-vestibular interaction using whole-body rotation rapidly and conveniently in the routine vestibular clinic. We examined 11 patients with cerebellar dysequilibrium and 25 patients with peripheral dysequilibrium for vestibulo-ocular reflex in darkness (DVOR), visually-enhanced vestibulo-ocular reflex (VEVOR), and fixation suppression of vestibulo-ocular reflex (FSVOR), and compared the results with those of examination for head-fixed smooth pursuit and fixation suppression during caloric stimulation. The manual rotation stimuli were 0.5-0.75 Hz in frequency and 60-90 degrees /s in maximal angular velocity. Gain of vestibulo-ocular reflex in darkness was not significantly correlated with maximal slow phase velocity (MSPV) of caloric-induced nystagmus at that stimulus condition either in patients with peripheral dysequilibrium or in those with cerebellar dysequilibrium. An index for fixation suppression of vestibulo-ocular reflex during rotation stimulus was significantly lower in patients with cerebellar dysequilibrium than in normal control subjects and those with peripheral dysequilibrium. On the other hand, there was no significant difference among the two disease groups and the normal control group in gain of visually-enhanced vestibulo-ocular reflex. In about a half of patients with cerebellar dysequilibrium, measured smooth pursuit gain was lower than estimated smooth pursuit gain calculated based on a simple superposition theory of vestibulo-ocular reflex and smooth pursuit. Testing fixation suppression using the present system is an unusually convenient tool for detection of cerebellar dysequilibrium.

  6. Memory and Perception-based Facial Image Reconstruction.

    Science.gov (United States)

    Chang, Chi-Hsun; Nemrodov, Dan; Lee, Andy C H; Nestor, Adrian

    2017-07-26

    Visual memory for faces has been extensively researched, especially regarding the main factors that influence face memorability. However, what we remember exactly about a face, namely, the pictorial content of visual memory, remains largely unclear. The current work aims to elucidate this issue by reconstructing face images from both perceptual and memory-based behavioural data. Specifically, our work builds upon and further validates the hypothesis that visual memory and perception share a common representational basis underlying facial identity recognition. To this end, we derived facial features directly from perceptual data and then used such features for image reconstruction separately from perception and memory data. Successful levels of reconstruction were achieved in both cases for newly-learned faces as well as for familiar faces retrieved from long-term memory. Theoretically, this work provides insights into the content of memory-based representations while, practically, it may open the path to novel applications, such as computer-based 'sketch artists'.

  7. Remote Sensing and GIS Applied to the Landscape for the Environmental Restoration of Urbanizations by Means of 3D Virtual Reconstruction and Visualization (Salamanca, Spain

    Directory of Open Access Journals (Sweden)

    Antonio Miguel Martínez-Graña

    2016-01-01

    Full Text Available The key focus of this paper is to establish a procedure that combines the use of Geographical Information Systems (GIS and remote sensing in order to achieve simulation and modeling of the landscape impact caused by construction. The procedure should be easily and inexpensively developed. With the aid of 3D virtual reconstruction and visualization, this paper proposes that the technologies of remote sensing and GIS can be applied to the landscape for post-urbanization environmental restoration. The goal is to create a rural zone in an urban development sector that integrates the residential areas and local infrastructure into the surrounding natural environment in order to measure the changes to the preliminary urban design. The units of the landscape are determined by means of two cartographic methods: (1 indirect, using the components of the landscape; and (2 direct methods, using the landscape’s elements. The visual basins are calculated for the most transited by the population points, while establishing the zones that present major impacts for the urbanization of their landscape. Based on this, the different construction types are distributed (one-family houses, blocks of houses, etc., selecting the types of plant masses either with ornamentals or integration depending on the zone; integrating water channels, creating a water channel in recirculation and green spaces and leisure time facilities. The techniques of remote sensing and GIS allow for the visualization and modeling of the urbanization in 3D, simulating the virtual reality of the infrastructure as well as the actions that need to be taken for restoration, thereby providing at a low cost an understanding of landscape integration before it takes place.

  8. Technical note: Validation of a chemical pregnancy test in dairy cows that uses whole blood, shortened incubation times, and visual readout.

    Science.gov (United States)

    Mayo, L M; Moore, S G; Poock, S E; Silvia, W J; Lucy, M C

    2016-09-01

    Chemical pregnancy testing is an alternative to traditional methods of pregnancy diagnosis (either manual palpation or ultrasound) in postpartum dairy cows and heifers. The objective was to validate a chemical pregnancy test that confers the advantages of using whole blood, rapid incubation times, and visual readout. Blood and milk samples were collected from Holstein dairy cows [n=320; 162±62 (mean ± SD) d in milk] on a confinement farm in northeast Missouri at 28 d after artificial insemination (AI). The samples were assayed for pregnancy-associated glycoproteins (PAG) by using a rapid visual test as well as traditional plasma- and milk-based tests. Transrectal ultrasonography diagnosis for pregnancy at 35 to 38 d after AI was the reference (gold) standard for all PAG tests. One hundred fifty-nine cows were diagnosed as pregnant by the reference standard (pregnancies per AI=49.7%). The tests were ELISA and either optical density (OD; measured with a microtiter plate reader; plasma, milk, and rapid visual tests) or visual readout (rapid visual test) were used to diagnose pregnancy. When OD was used, the percentage of pregnant cows classified correctly (sensitivity) for the plasma, milk, and rapid visual tests were 97±1, 96±2, and 95±1% (±SE), respectively. The sensitivity of the rapid visual test when assessed visually was 98±1%. The specificity (proportion of nonpregnant cows classified correctly) for the plasma, milk, and rapid visual was 94±2%, 94±2%, and 93±2% when an OD was used. When read visually, the specificity of the rapid visual test was lesser (85±3%) because some cows with faint visual signals yielded false positive diagnosis. The overall accuracy (proportion of pregnant and nonpregnant cows diagnosed correctly) was similar for all tests (plasma, milk, rapid visual OD, and rapid visual; 96±1, 95±1, 94±1, and 92±2%, respectively). In a second experiment, lactating Holstein cows (n=291) from 4 commercial confinement dairy farms in western

  9. Validity of the visual analogue scale as an instrument to measure self-efficacy in resuscitation skills.

    Science.gov (United States)

    Turner, Nigel M; van de Leemput, Anita J; Draaisma, Jos M T; Oosterveld, Paul; ten Cate, Olle Th J

    2008-05-01

    Self-efficacy is an important factor in many areas of medical education, including self-assessment and self-directed learning, but has been little studied in resuscitation training, possibly because of the lack of a simple measurement instrument. We aimed to assess the validity of a visual analogue scale (VAS) linked to a single question as an instrument to measure self-efficacy with respect to resuscitation skills by comparing the VAS with a questionnaire and using known-groups comparisons. We developed questionnaires to measure self-efficacy for a number of resuscitation tasks and for computer skills. These were compared with VASs linked to a single question per task, using a multi-trait, multi-method matrix. We also used known-groups comparisons of self-efficacy in specific professional groups. There was good correlation between the questionnaires and the VASs for self-efficacy for specific resuscitation tasks. There was a less clear correlation for self-efficacy for paediatric resuscitation overall. There was no correlation between self-efficacy for resuscitation and computer tasks. In specific professional groups, measured self-efficacy accorded with theoretical predictions. A VAS linked to a single question appears to be a valid method of measuring self-efficacy with respect to specific well defined resuscitation tasks, but should be used with caution for multi-faceted tasks.

  10. Reliability and validity of the pain observation scale for young children and the visual analogue scale in children with burns.

    Science.gov (United States)

    de Jong, A E E; Bremer, M; Schouten, M; Tuinebreijer, W E; Faber, A W

    2005-03-01

    The aim of this study was to assess if the pain observation scale for young children (POCIS) and the visual analogue scale (VAS) are reliable and valid instruments to measure procedural and background pain in burned children aged 0-4 years. Burn care nurses (n=73) rated pain from 24 fragments of videotaped children during wound care procedures and during periods of rest using the POCIS and the VAS. Intraclass correlations were used to assess inter-rater and intra-rater reliability for the POCIS and the VAS. Internal consistency for POCIS was assessed by Cronbach's alpha. The POCIS has shown poor to moderate inter-rater reliability, moderate to good intra-rater reliability and an acceptable internal consistency. The VAS turned out to have poor inter-rater reliability and poor to moderate intra-rater reliability. Due to poor results of inter-rater reliability in both scales, construct validation is left undone until more acceptable results are obtained. Factors explaining the results are the large number of raters, the manner they were trained and a lack of variation between pain classes in video fragments. Although not all results were satisfying, an easy to use scale as POCIS has promising qualities and deserves further reliability research.

  11. A Visual Analog Scale to assess anxiety in children during anesthesia induction (VAS-I): Results supporting its validity in a sample of day care surgery patients.

    Science.gov (United States)

    Berghmans, Johan M; Poley, Marten J; van der Ende, Jan; Weber, Frank; Van de Velde, Marc; Adriaenssens, Peter; Himpe, Dirk; Verhulst, Frank C; Utens, Elisabeth

    2017-09-01

    The modified Yale Preoperative Anxiety Scale is widely used to assess children's anxiety during induction of anesthesia, but requires training and its administration is time-consuming. A Visual Analog Scale, in contrast, requires no training, is easy-to-use and quickly completed. The aim of this study was to evaluate a Visual Analog Scale as a tool to assess anxiety during induction of anesthesia and to determine cut-offs to distinguish between anxious and nonanxious children. Four hundred and one children (1.5-16 years) scheduled for daytime surgery were included. Children's anxiety during induction was rated by parents and anesthesiologists on a Visual Analog Scale and by a trained observer on the modified Yale Preoperative Anxiety Scale. Psychometric properties assessed were: (i) concurrent validity (correlations between parents' and anesthesiologists' Visual Analog Scale and modified Yale Preoperative Anxiety Scale scores); (ii) construct validity (differences between subgroups according to the children's age and the parents' anxiety as assessed by the State-Trait Anxiety Inventory); (iii) cross-informant agreement using Bland-Altman analysis; (iv) cut-offs to distinguish between anxious and nonanxious children (reference: modified Yale Preoperative Anxiety Scale ≥30). Correlations between parents' and anesthesiologists' Visual Analog Scale and modified Yale Preoperative Anxiety Scale scores were strong (0.68 and 0.73, respectively). Visual Analog Scale scores were higher for children ≤5 years compared to children aged ≥6. Visual Analog Scale scores of children of high-anxious parents were higher than those of low-anxious parents. The mean difference between parents' and anesthesiologists' Visual Analog Scale scores was 3.6, with 95% limits of agreement (-56.1 to 63.3). To classify anxious children, cut-offs for parents (≥37 mm) and anesthesiologists (≥30 mm) were established. The present data provide preliminary data for the validity of a Visual

  12. Validation of exposure visualization and audible distance emission for navigated temporal bone drilling in phantoms.

    Directory of Open Access Journals (Sweden)

    Eduard H J Voormolen

    Full Text Available BACKGROUND: A neuronavigation interface with extended function as compared with current systems was developed to aid during temporal bone surgery. The interface, named EVADE, updates the prior anatomical image and visualizes the bone drilling process virtually in real-time without need for intra-operative imaging. Furthermore, EVADE continuously calculates the distance from the drill tip to segmented temporal bone critical structures (e.g. the sigmoid sinus and facial nerve and produces audiovisual warnings if the surgeon drills in too close vicinity. The aim of this study was to evaluate the accuracy and surgical utility of EVADE in physical phantoms. METHODOLOGY/PRINCIPAL FINDINGS: We performed 228 measurements assessing the position accuracy of tracking a navigated drill in the operating theatre. A mean target registration error of 1.33±0.61 mm with a maximum error of 3.04 mm was found. Five neurosurgeons each drilled two temporal bone phantoms, once using EVADE, and once using a standard neuronavigation interface. While using standard neuronavigation the surgeons damaged three modeled temporal bone critical structures. No structure was hit by surgeons utilizing EVADE. Surgeons felt better orientated and thought they had improved tumor exposure with EVADE. Furthermore, we compared the distances between surface meshes of the virtual drill cavities created by EVADE to actual drill cavities: average maximum errors of 2.54±0.49 mm and -2.70±0.48 mm were found. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that EVADE gives accurate feedback which reduces risks of harming modeled critical structures compared to a standard neuronavigation interface during temporal bone phantom drilling.

  13. Development and validation of an achievement test in introductory quantum mechanics: The Quantum Mechanics Visualization Instrument (QMVI)

    Science.gov (United States)

    Cataloglu, Erdat

    The purpose of this study was to construct a valid and reliable multiple-choice achievement test to assess students' understanding of core concepts of introductory quantum mechanics. Development of the Quantum Mechanics Visualization Instrument (QMVI) occurred across four successive semesters in 1999--2001. During this time 213 undergraduate and graduate students attending the Pennsylvania State University (PSU) at University Park and Arizona State University (ASU) participated in this development and validation study. Participating students were enrolled in four distinct groups of courses: Modern Physics, Undergraduate Quantum Mechanics, Graduate Quantum Mechanics, and Chemistry Quantum Mechanics. Expert panels of professors of physics experienced in teaching quantum mechanics courses and graduate students in physics and science education established the core content and assisted in the validating of successive versions of the 24-question QMVI. Instrument development was guided by procedures outlined in the Standards for Educational and Psychological Testing (AERA-APA-NCME, 1999). Data gathered in this study provided information used in the development of successive versions of the QMVI. Data gathered in the final phase of administration of the QMVI also provided evidence that the intended score interpretation of the QMVI achievement test is valid and reliable. A moderate positive correlation coefficient of 0.49 was observed between the students' QMVI scores and their confidence levels. Analyses of variance indicated that students' scores in Graduate Quantum Mechanics and Undergraduate Quantum Mechanics courses were significantly higher than the mean scores of students in Modern Physics and Chemistry Quantum Mechanics courses (p < 0.05). That finding is consistent with the additional understanding and experience that should be anticipated in graduate students and junior-senior level students over sophomore physics majors and majors in another field. The moderate

  14. Visualization of pulmonary clearance mechanisms via noninvasive optical imaging validated by near-infrared flow cytometry.

    Science.gov (United States)

    Zhou, Haiying; Gunsten, Sean P; Zhegalova, Natalia G; Bloch, Sharon; Achilefu, Samuel; Christopher Holley, J; Schweppe, Daniel; Akers, Walter; Brody, Steven L; Eades, William C; Berezin, Mikhail Y

    2015-05-01

    In vivo optical imaging with near-infrared (NIR) probes is an established method of diagnostics in preclinical and clinical studies. However, the specificities of these probes are difficult to validate ex vivo due to the lack of NIR flow cytometry. To address this limitation, we modified a flow cytometer to include an additional NIR channel using a 752 nm laser line. The flow cytometry system was tested using NIR microspheres and cell lines labeled with a combination of visible range and NIR fluorescent dyes. The approach was verified in vivo in mice evaluated for immune response in lungs after intratracheal delivery of the NIR contrast agent. Flow cytometry of cells obtained from the lung bronchoalveolar lavage demonstrated that the NIR dye was taken up by pulmonary macrophages as early as 4-h post-injection. This combination of optical imaging with NIR flow cytometry extends the capability of imaging and enables complementation of in vivo imaging with cell-specific studies. © 2015 International Society for Advancement of Cytometry.

  15. Reliability and validity of observer ratings of pain using the visual analog scale (VAS) in infants undergoing immunization injections.

    Science.gov (United States)

    Taddio, Anna; O'Brien, Lisa; Ipp, Moshe; Stephens, Derek; Goldbach, Morton; Koren, Gideon

    2009-12-15

    We tested the reliability and validity of observer-rated pain in infants undergoing immunization using the visual analog scale (VAS). Pain was assessed in real time and later, from videotapes, in 120 1-year-old infants participating in a double-blind randomized controlled trial of amethocaine vs. placebo. Altogether, 2 (1 physician, 1 non-physician) of 4 raters [2 physicians, 2 non-physicians (nurse and graduate student)] independently assessed baseline and vaccine injection pain using a 100mm unmarked VAS line. Intra- and inter-rater reliability, assessed using the intra-class correlation coefficient (ICC), ranged from 0.69 to 0.91 and 0.55 to 0.97, respectively. Bland-Altman plots demonstrated no evidence of bias between real time and video assessments. When scores were dichotomized into 2 groups (no pain and pain) using a cut-off of >or=30mm, intra-rater reliability ranged from 0.35 to 0.92. The percent of scores deviating by >20mm was 4.5-14.29%. Criterion validity was demonstrated by correlations between the VAS and Modified Behavioural Pain Scale, a validated observational measure; (rho: 0.81-0.94). Injection scores were lower in the amethocaine group, when comparing difference (baseline-injection) or dichotomized scores; significance (pVAS as an outcome measure for acute procedural pain in infants. However, different conclusions may be reached about the effectiveness of analgesic interventions depending on the rater. Sources of variability include use of multiple raters, rater focus (procedure vs. child) and experience level.

  16. How valid is the self-administered visual analogue scale for assessing the health status of elderly people?

    Science.gov (United States)

    Kimura, Tomoaki; Hayashida, Kenshi; Araki, Yoshimitsu; Morita, Takako; Yamaguchi, Noboru; Eboshida, Akira

    2008-12-01

    The population of Japan is aging rapidly, and maintaining the quality of life of elderly people has become an important issue in contemporary Japan. This study was conducted to verify the validity of the self-administered visual analogue scale (VAS) for assessing the health status of elderly people. A survey was conducted in two villages in western Japan in 2003. A total of 2040 participants, aged between 60 and 75 years, completed questionnaires comprising the VAS and six Likert-type items for health status, physical strength, life enjoyment, appetite, sleep, and life satisfaction. Data of the valid participants who properly completed both the VAS and the Likert-type item on health status were analyzed (n=1579, 77.4%). Among the Likert-type items, the VAS score was the most associated with health status (r = 0.532), followed by physical strength (r = 0.509). The VAS score showed a weak negative correlation with age (r = -0.130), but no association with socioeconomic factors such as the number of family members or annual income. The correlations between the VAS and the Likert-type item on health status varied between categories in some attributes. Since the VAS score was moderately correlated with similar questions about health status in the Likert-type health questionnaire, it was considered that the VAS is a valid self-administered instrument for collecting data on the health status of elderly people. However, further investigations need to be conducted to improve the VAS and to establish better explanations for aged respondents.

  17. Validation of Spherically Symmetric Inversion by Use of a Tomographically Reconstructed Three-Dimensional Electron Density of the Solar Corona

    Science.gov (United States)

    Wang, Tongjiang; Davila, Joseph M.

    2014-01-01

    Determining the coronal electron density by the inversion of white-light polarized brightness (pB) measurements by coronagraphs is a classic problem in solar physics. An inversion technique based on the spherically symmetric geometry (spherically symmetric inversion, SSI) was developed in the 1950s and has been widely applied to interpret various observations. However, to date there is no study of the uncertainty estimation of this method. We here present the detailed assessment of this method using a three-dimensional (3D) electron density in the corona from 1.5 to 4 solar radius as a model, which is reconstructed by a tomography method from STEREO/COR1 observations during the solar minimum in February 2008 (Carrington Rotation, CR 2066).We first show in theory and observation that the spherically symmetric polynomial approximation (SSPA) method and the Van de Hulst inversion technique are equivalent. Then we assess the SSPA method using synthesized pB images from the 3D density model, and find that the SSPA density values are close to the model inputs for the streamer core near the plane of the sky (POS) with differences generally smaller than about a factor of two; the former has the lower peak but extends more in both longitudinal and latitudinal directions than the latter. We estimate that the SSPA method may resolve the coronal density structure near the POS with angular resolution in longitude of about 50 deg. Our results confirm the suggestion that the SSI method is applicable to the solar minimum streamer (belt), as stated in some previous studies. In addition, we demonstrate that the SSPA method can be used to reconstruct the 3D coronal density, roughly in agreement with the reconstruction by tomography for a period of low solar activity (CR 2066). We suggest that the SSI method is complementary to the 3D tomographic technique in some cases, given that the development of the latter is still an ongoing research effort.

  18. Test of Gross Motor Development-3 (TGMD-3) with the Use of Visual Supports for Children with Autism Spectrum Disorder: Validity and Reliability

    Science.gov (United States)

    Allen, K. A.; Bredero, B.; Van Damme, T.; Ulrich, D. A.; Simons, J.

    2017-01-01

    The validity and reliability of the Test of Gross Motor Development-3 (TGMD-3) were measured, taking into consideration the preference for visual learning of children with autism spectrum disorder (ASD). The TGMD-3 was administered to 14 children with ASD (4-10 years) and 21 age-matched typically developing children under two conditions: TGMD-3…

  19. Determination of snow avalanche return periods using a tree-ring based reconstruction in the French Alps: cross validation with the predictions of a statistical-dynamical model

    Science.gov (United States)

    Schläppy, Romain; Eckert, Nicolas; Jomelli, Vincent; Grancher, Delphine; Brunstein, Daniel; Stoffel, Markus; Naaim, Mohamed

    2013-04-01

    rare events, i.e. to the tail of the local runout distance distribution. Furthermore, a good agreement exists with the statistical-numerical model's prediction, i.e. a 10-40 m difference for return periods ranging between 10 and 300 years, which is rather small with regards to the uncertainty levels to be considered in avalanche probabilistic modeling and dendrochronological reconstructions. It is important to note that such a cross validation on independent extreme predictions has never been undertaken before. It suggest that i) dendrochronological reconstruction can provide valuable information for anticipating future extreme avalanche events in the context of risk management, and, in turn, that ii) the statistical-numerical model, while properly calibrated, can be used with reasonable confidence to refine these predictions, with for instance evaluation of pressure and flow depth distributions at each position of the runout zone. A strong sensitivity to the determination of local avalanche and dendrological record frequencies is however highlighted, indicating that this step is an essential step for an accurate probabilistic characterization of large-extent events.

  20. Study on accident reconstruction model. Validation of the model; Shototsu jiko saigen no kaiseki moderu ni kansuru kenkyu. Moderu no kensho

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, H.; Wei, Lang [Japan Automobile Research Inst., Tokyo (Japan); Nakatsuji, T. [Hokkaido Univ., Sapporo (Japan). Faculty of Engineering

    1995-10-01

    In a vehicle collision accident analysis, the behavior of the vehicle immediately before and after the occurrence of the accident is presumed from the situation of the accident site such as the tire marks remaining at the site, the condition of the body deformation, the last position of the vehicle`s stoppage, etc.. The vehicle collision accident analysis is called also the accident reconstruction, and various analytic models have been proposed, but many of them are analytic models to presume, prior to the collision, the situation after it, and models which analyze the pre-collision situation from the situation after it are not many. In this study, an accident analytic model has been prepared which can reconstruct the vehicle`s speed prior to the collision and its behavior after it only from the stoppage position of the vehicle after the collision and the position of the vehicle at the point of collision by adapting the law of conservation of momentum and the Gim`s tire model. In other words, each analytic equation of the momentum analytic model immediately after the collision, the two-dimensional vehicle movement, the dynamic model, and the verification model of the speed immediately before the collision have been roughly explained and by comparing 5 examples of the experimental results of actual vehicles` collisions with the analytic calculation results of the above model, the validity of the above model has been verified. 4 refs., 6 figs., 1 tab.

  1. Three-dimensional visualization and characterization of bone structure using reconstructed in-vitro μCT images: A pilot study for bone microarchitecture analysis

    Energy Technology Data Exchange (ETDEWEB)

    Latief, Fourier Dzar Eljabbar, E-mail: fourier@fi.itb.ac.id [Physics of Earth and Complex Systems, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia); Dewi, Dyah Ekashanti Octorina [2Biomedical Engineering Research Division, School of Electrical Engineering and Informatics, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia); Shari, Mohd Aliff Bin Mohd [Faculty of Electrical Engineering, Universiti Teknologi MARA Malaysia, 40000 Shah Alam, Selangor (Malaysia)

    2014-03-24

    Micro Computed Tomography (μCT) has been largely used to perform micrometer scale imaging of specimens, bone biopsies and small animals for the study of porous or cavity-containing objects. One of its favored applications is for assessing structural properties of bone. In this research, we perform a pilot study to visualize and characterize bone structure of a chicken bone thigh, as well as to delineate its cortical and trabecular bone regions. We utilize an In-Vitro μCT scanner Skyscan 1173 to acquire a three dimensional image data of a chicken bone thigh. The thigh was scanned using X-ray voltage of 45 kV and current of 150 μA. The reconstructed images have spatial resolution of 142.50 μm/pixel. Using image processing and analysis e.i segmentation by thresholding the gray values (which represent the pseudo density) and binarizing the images, we were able to visualize each part of the bone, i.e., the cortical and trabecular regions. Total volume of the bone is 4663.63 mm{sup 3}, and the surface area of the bone is 7913.42 mm{sup 2}. The volume of the cortical is approximately 1988.62 mm{sup 3} which is nearly 42.64% of the total bone volume. This pilot study has confirmed that the μCT is capable of quantifying 3D bone structural properties and defining its regions separately. For further development, these results can be improved for understanding the pathophysiology of bone abnormality, testing the efficacy of pharmaceutical intervention, or estimating bone biomechanical properties.

  2. The visual analogue WOMAC 3.0 scale--internal validity and responsiveness of the VAS version.

    Science.gov (United States)

    Kersten, Paula; White, Peter J; Tennant, Alan

    2010-04-30

    Many people suffer with Osteoarthritis (OA) and subsequent morbidity. Therefore, measuring outcome associated with OA is important. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) has been a widely used patient reported outcome in OA. However, there is relatively little evidence to support the use of the Visual Analogue Scale (VAS) version of the scale. We aimed to explore the internal validity and responsiveness of this VAS version of the WOMAC. Patients with chronic hip or knee pain of mechanical origin, waiting for a hip or knee joint replacement completed the WOMAC as part of a study to investigate the effects of acupuncture and placebo controls. Validity was tested using factor analysis and Rasch analysis, and responsiveness using standardised response means. Two hundred and twenty one patients (mean age 66.8, SD 8.29, 58% female) were recruited. Factor and Rasch analysis confirmed unidimensional Pain and Physical Functioning scales, capable of transformation to interval scaling and invariant over time. Some Differential Item Functioning (DIF) was observed, but this cancelled out at the test level. The Stiffness scale fitted the Rasch model but adjustments for DIF could not be made due to the shortness of the scale. Using the interval transformed data, Standardised Response Means were smaller than when using the raw, ordinal data. The WOMAC Pain and Physical Functioning subscales satisfied unidimensionality and ordinal scaling tests, and the ability to transform to an interval scale. Some Differential Item Functioning was observed, but this cancelled out at the test level and, by doing so, at the same time removed the disturbance of unidimensionality. The scaling characteristics of sets of items which use VAS require further analysis, as it would appear that they can lead to spurious levels of responsiveness and scale compression because they exaggerate the distortion of the ordinal scale. UKCRN study ID: 4881 ISRCTN78434638.

  3. Optimisation and validation of a 3D reconstruction algorithm for single photon emission computed tomography by means of GATE simulation platform; Optimisation et validation d'un algorithme de reconstruction 3D en Tomographie d'Emission Monophotonique a l'aide de la plate forme de simulation GATE

    Energy Technology Data Exchange (ETDEWEB)

    El Bitar, Ziad [Ecole Doctorale des Sciences Fondamentales, Universite Blaise Pascal, U.F.R de Recherches Scientifiques et Techniques, 34, avenue Carnot - BP 185, 63006 Clermont-Ferrand Cedex (France); Laboratoire de Physique Corpusculaire, CNRS/IN2P3, 63177 Aubiere (France)

    2006-12-15

    Although time consuming, Monte-Carlo simulations remain an efficient tool enabling to assess correction methods for degrading physical effects in medical imaging. We have optimized and validated a reconstruction method baptized F3DMC (Fully 3D Monte Carlo) in which the physical effects degrading the image formation process were modelled using Monte-Carlo methods and integrated within the system matrix. We used the Monte-Carlo simulation toolbox GATE. We validated GATE in SPECT by modelling the gamma-camera (Philips AXIS) used in clinical routine. Techniques of threshold, filtering by a principal component analysis and targeted reconstruction (functional regions, hybrid regions) were used in order to improve the precision of the system matrix and to reduce the number of simulated photons as well as the time consumption required. The EGEE Grid infrastructures were used to deploy the GATE simulations in order to reduce their computation time. Results obtained with F3DMC were compared with the reconstruction methods (FBP, ML-EM, MLEMC) for a simulated phantom and with the OSEM-C method for the real phantom. Results have shown that the F3DMC method and its variants improve the restoration of activity ratios and the signal to noise ratio. By the use of the grid EGEE, a significant speed-up factor of about 300 was obtained. These results should be confirmed by performing studies on complex phantoms and patients and open the door to a unified reconstruction method, which could be used in SPECT and also in PET. (author)

  4. Validation of the Gate simulation platform in single photon emission computed tomography and application to the development of a complete 3-dimensional reconstruction algorithm; Validation de la plate-forme de simulation GATE en tomographie a emission monophotonique et application au developpement d'un algorithme de reconstruction 3D complete

    Energy Technology Data Exchange (ETDEWEB)

    Lazaro, D

    2003-10-01

    Monte Carlo simulations are currently considered in nuclear medical imaging as a powerful tool to design and optimize detection systems, and also to assess reconstruction algorithms and correction methods for degrading physical effects. Among the many simulators available, none of them is considered as a standard in nuclear medical imaging: this fact has motivated the development of a new generic Monte Carlo simulation platform (GATE), based on GEANT4 and dedicated to SPECT/PET (single photo emission computed tomography / positron emission tomography) applications. We participated during this thesis to the development of the GATE platform within an international collaboration. GATE was validated in SPECT by modeling two gamma cameras characterized by a different geometry, one dedicated to small animal imaging and the other used in a clinical context (Philips AXIS), and by comparing the results obtained with GATE simulations with experimental data. The simulation results reproduce accurately the measured performances of both gamma cameras. The GATE platform was then used to develop a new 3-dimensional reconstruction method: F3DMC (fully 3-dimension Monte-Carlo) which consists in computing with Monte Carlo simulation the transition matrix used in an iterative reconstruction algorithm (in this case, ML-EM), including within the transition matrix the main physical effects degrading the image formation process. The results obtained with the F3DMC method were compared to the results obtained with three other more conventional methods (FBP, MLEM, MLEMC) for different phantoms. The results of this study show that F3DMC allows to improve the reconstruction efficiency, the spatial resolution and the signal to noise ratio with a satisfactory quantification of the images. These results should be confirmed by performing clinical experiments and open the door to a unified reconstruction method, which could be applied in SPECT but also in PET. (author)

  5. Validation of a method for ionospheric electron density reconstruction by means of vertical incidence data during quiet and storm periods

    Directory of Open Access Journals (Sweden)

    P. Coïsson

    2005-06-01

    Full Text Available A preliminary validation of the technique developed using the NeQuick ionospheric model and the «effective ionization parameter» Az, based on vertical total electron content data ingestion, was carried out in a previous study. The current study was performed to extend the analyzed conditions and confirm the results. The method to validate this technique is based on a comparison between hourly F2 peak values measured with Vertical Incidence (VI soundings and those calculated with the new technique. Data corresponding to different hours and seasons (equinox, summer solstice, and winter solstice during the period 2000-2003 (high and medium solar activity conditions were compared for all available ionosonde stations. The results show a good agreement between foF2 and hmF2 values obtained with the new technique and measurements from vertical incidence soundings during quiet and storms conditions.

  6. Utility and validity of a single-item visual analog scale for measuring dental anxiety in clinical practice.

    Science.gov (United States)

    Appukuttan, Devapriya; Vinayagavel, Mythreyi; Tadepalli, Anupama

    2014-06-01

    We evaluated whether a visual analog scale (VAS) was comparable to the multi-item Modified Dental Anxiety Scale (MDAS) in assessing dental anxiety in clinical practice. In total, 200 consecutive patients aged 20-70 years who presented at the dental outpatient department of SRM Dental College, Chennai were enrolled. The test-retest value for the VAS was 0.968. The Spearman rank correlations between the VAS and MDAS items and total score were significant (P VAS also showed a strong correlation (r = 0.473, P VAS cut-off value of ≥4.8 was selected to discriminate between patients who were and were not anxious, and a cut-off value of ≥7 was selected to identify patients with dental phobia. The weighted kappa was 69% for agreement between MDAS and the VAS in identifying patients with and without dental anxiety at cut-offs of 13 and 4.75, respectively. The VAS was found to be a valid measure and was comparable to the multi-item MDAS.

  7. 'The surface management system' (SuMS) database: a surface-based database to aid cortical surface reconstruction, visualization and analysis

    Science.gov (United States)

    Dickson, J.; Drury, H.; Van Essen, D. C.

    2001-01-01

    Surface reconstructions of the cerebral cortex are increasingly widely used in the analysis and visualization of cortical structure, function and connectivity. From a neuroinformatics perspective, dealing with surface-related data poses a number of challenges. These include the multiplicity of configurations in which surfaces are routinely viewed (e.g. inflated maps, spheres and flat maps), plus the diversity of experimental data that can be represented on any given surface. To address these challenges, we have developed a surface management system (SuMS) that allows automated storage and retrieval of complex surface-related datasets. SuMS provides a systematic framework for the classification, storage and retrieval of many types of surface-related data and associated volume data. Within this classification framework, it serves as a version-control system capable of handling large numbers of surface and volume datasets. With built-in database management system support, SuMS provides rapid search and retrieval capabilities across all the datasets, while also incorporating multiple security levels to regulate access. SuMS is implemented in Java and can be accessed via a Web interface (WebSuMS) or using downloaded client software. Thus, SuMS is well positioned to act as a multiplatform, multi-user 'surface request broker' for the neuroscience community.

  8. Validity and reliability of the Rosenberg Self-Esteem Scale-Thai version as compared to the Self-Esteem Visual Analog Scale.

    Science.gov (United States)

    Piyavhatkul, Nawanant; Aroonpongpaisal, Suwanna; Patjanasoontorn, Niramol; Rongbutsri, Somchit; Maneeganondh, Somchit; Pimpanit, Wijitra

    2011-07-01

    To compare the validity and reliability of the Thai version of the Rosenberg Self-Esteem Scale with the Self-Esteem Visual Analog Scale. The Rosenberg Self-Esteem Scale was translated into Thai and its content-validity checked by bacA translation. The reliability of the Rosenberg Self-Esteem Scale compared with the Self-Esteem Visual Analog Scale was ther tested between February and March 2008 on 270 volunteers, including 135 patients with psychiatric illness and 135 normal volunteers. The authors analyzed the internal consistency and factor structure of the Rosenberg Self-Esteem Scale-Thai version and the correlation between it and the Visual Analog Scale. The Cronbach's Alpha for the Rosenberg Self-Esteem scale-Thai version was 0.849 and the Pearson's correlation between it and the Self-Esteem Visual Analog Scale 0.618 (p = 0.01). Two factors, viz, the positively and negatively framea items, from the Rosenberg Self-Esteem Scale-Thai version accounted for 44.04% and 12.10% of the variance, respectively. The Rosenberg Self-Esteem Scale-Thai version has acceptable reliability. The Self-Esteem Visual Analog Scale provides an effective measure of self-esteem.

  9. Validation of a Mexican food photograph album as a tool to visually estimate food amounts in adolescents.

    Science.gov (United States)

    Bernal-Orozco, M Fernanda; Vizmanos-Lamotte, Barbara; Rodríguez-Rocha, Norma P; Macedo-Ojeda, Gabriela; Orozco-Valerio, María; Rovillé-Sausse, Françoise; León-Estrada, Sandra; Márquez-Sandoval, Fabiola; Fernández-Ballart, Joan D

    2013-03-14

    The aim of the present study was to validate a food photograph album (FPA) as a tool to visually estimate food amounts, and to compare this estimation with that attained through the use of measuring cups (MC) and food models (FM). We tested 163 foods over fifteen sessions (thirty subjects/session; 10-12 foods presented in two portion sizes, 20-24 plates/session). In each session, subjects estimated food amounts with the assistance of FPA, MC and FM. We compared (by portion and method) the mean estimated weight and the mean real weight. We also compared the percentage error estimation for each portion, and the mean food percentage error estimation between methods. In addition, we determined the percentage error estimation of each method. We included 463 adolescents from three public high schools (mean age 17·1 (sd 1·2) years, 61·8 % females). All foods were assessed using FPA, 53·4 % of foods were assessed using MC, and FM was used for 18·4 % of foods. The mean estimated weight with all methods was statistically different compared with the mean real weight for almost all foods. However, a lower percentage error estimation was observed using FPA (2·3 v. 56·9 % for MC and 325 % for FM, P< 0·001). Also, when analysing error rate ranges between methods, there were more observations (P< 0·001) with estimation errors higher than 40 % with the MC (56·1 %), than with the FPA (27·5 %) and FM (44·9 %). In conclusion, although differences between estimated and real weight were statistically significant for almost all foods, comparisons between methods showed FPA to be the most accurate tool for estimating food amounts.

  10. Reliability and concurrent validity of visual analogue scale and modified verbal rating scale of pain assessment in adult patients with knee osteoathritis in Nigeria

    OpenAIRE

    M. O.B Olaogun; R. A. Adedoyin; R. O. Anifaloba

    2003-01-01

    The objective of this study was to determine the reliability and concurrent validity of two pain rating scales - Visual Analogue Scale (VAS) and Verbal Rating Scale (VRS). The verbal rating scale was modified by translating the English description of subjective pain experience into vernacular (Yoruba) equivalents and rating the knee pain when the patient was  standing with the knee  flexed . Twenty seven patients who were clinically and radiologically diagnosed with osteoarthritis (OA) and wi...

  11. Catch-up validation study of an in vitro skin irritation test method based on an open source reconstructed epidermis (phase I).

    Science.gov (United States)

    Mewes, K R; Fischer, A; Zöller, N N; Laubach, V; Bernd, A; Jacobs, A; van Rompay, A; Liebsch, M; Pirow, R; Petersohn, D

    2016-10-01

    We have developed a new in vitro skin irritation test based on an open source reconstructed epidermis (OS-REp) with openly accessible protocols for tissue production and test performance. Due to structural, mechanistic and procedural similarity, a blinded catch-up validation study for skin irritation according to OECD Performance Standards (PS) was conducted in three laboratories to promote regulatory acceptance, with OS-REp models produced at a single production site only. While overall sensitivity and predictive capacity met the PS requirements, overall specificity was only 57%. A thorough analysis of the test results led to the assumption that some of the false-positive classifications could have been evoked by volatile skin-irritating chemicals tested in the same culture plate as the non-irritants falsely predicted as irritants. With GC/MS and biological approaches the cross-contamination effect was confirmed and the experimental set-up adapted accordingly. Retesting of the affected chemicals with the improved experimental set-up and otherwise identical protocol resulted in correct classifications as non-irritants. Taking these re-test results into account, 93% overall sensitivity, 70% specificity and 82% accuracy was achieved, which is in accordance with the OECD PS. A sufficient reliability of the method was indicated by a within-laboratory-reproducibility of 85-95% and a between-laboratory-reproducibility of 90%. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Predicting Glycerophosphoinositol Identities in Lipidomic Datasets Using VaLID (Visualization and Phospholipid Identification)—An Online Bioinformatic Search Engine

    Science.gov (United States)

    McDowell, Graeme S. V.; Taylor, Graeme P.; Fai, Stephen; Bennett, Steffany A. L.

    2014-01-01

    The capacity to predict and visualize all theoretically possible glycerophospholipid molecular identities present in lipidomic datasets is currently limited. To address this issue, we expanded the search-engine and compositional databases of the online Visualization and Phospholipid Identification (VaLID) bioinformatic tool to include the glycerophosphoinositol superfamily. VaLID v1.0.0 originally allowed exact and average mass libraries of 736,584 individual species from eight phospholipid classes: glycerophosphates, glyceropyrophosphates, glycerophosphocholines, glycerophosphoethanolamines, glycerophosphoglycerols, glycerophosphoglycerophosphates, glycerophosphoserines, and cytidine 5′-diphosphate 1,2-diacyl-sn-glycerols to be searched for any mass to charge value (with adjustable tolerance levels) under a variety of mass spectrometry conditions. Here, we describe an update that now includes all possible glycerophosphoinositols, glycerophosphoinositol monophosphates, glycerophosphoinositol bisphosphates, and glycerophosphoinositol trisphosphates. This update expands the total number of lipid species represented in the VaLID v2.0.0 database to 1,473,168 phospholipids. Each phospholipid can be generated in skeletal representation. A subset of species curated by the Canadian Institutes of Health Research Training Program in Neurodegenerative Lipidomics (CTPNL) team is provided as an array of high-resolution structures. VaLID is freely available and responds to all users through the CTPNL resources web site. PMID:24701584

  13. Validity and reliability of an online visual-spatial working memory task for self-reliant administration in school-aged children.

    Science.gov (United States)

    Van de Weijer-Bergsma, Eva; Kroesbergen, Evelyn H; Prast, Emilie J; Van Luit, Johannes E H

    2015-09-01

    Working memory is an important predictor of academic performance, and of math performance in particular. Most working memory tasks depend on one-to-one administration by a testing assistant, which makes the use of such tasks in large-scale studies time-consuming and costly. Therefore, an online, self-reliant visual-spatial working memory task (the Lion game) was developed for primary school children (6-12 years of age). In two studies, the validity and reliability of the Lion game were investigated. The results from Study 1 (n = 442) indicated satisfactory six-week test-retest reliability, excellent internal consistency, and good concurrent and predictive validity. The results from Study 2 (n = 5,059) confirmed the results on the internal consistency and predictive validity of the Lion game. In addition, multilevel analysis revealed that classroom membership influenced Lion game scores. We concluded that the Lion game is a valid and reliable instrument for the online computerized and self-reliant measurement of visual-spatial working memory (i.e., updating).

  14. Visual Image-Induced Craving for Ethanol (VICE): Development, Validation, and a Pilot fMRI Study

    National Research Council Canada - National Science Library

    Holla, Bharath; Viswanath, Biju; Agarwal, Sri Mahavir; Kalmady, Sunil Vasu; Maroky, Ami Sebastian; Jayarajan, Deepak; Bharath, Rose Dawn; Venkatasubramanian, Ganesan; Benegal, Vivek

    2014-01-01

    ...). Alcohol-related visual cues (ARCs) in 5 scenarios were photographed, which included pictures of bars, alcoholic beverage bottles, pouring of alcohol into glasses, glasses filled with alcohol, and scenes of people sipping alcohol...

  15. Calibration and Validation of a Detailed Architectural Canopy Model Reconstruction for the Simulation of Synthetic Hemispherical Images and Airborne LiDAR Data

    Directory of Open Access Journals (Sweden)

    Magnus Bremer

    2017-02-01

    Full Text Available Canopy density measures such as the Leaf Area Index (LAI have become standardized mapping products derived from airborne and terrestrial Light Detection And Ranging (aLiDAR and tLiDAR, respectively data. A specific application of LiDAR point clouds is their integration into radiative transfer models (RTM of varying complexity. Using, e.g., ray tracing, this allows flexible simulations of sub-canopy light condition and the simulation of various sensors such as virtual hemispherical images or waveform LiDAR on a virtual forest plot. However, the direct use of LiDAR data in RTMs shows some limitations in the handling of noise, the derivation of surface areas per LiDAR point and the discrimination of solid and porous canopy elements. In order to address these issues, a strategy upgrading tLiDAR and Digital Hemispherical Photographs (DHP into plausible 3D architectural canopy models is suggested. The presented reconstruction workflow creates an almost unbiased virtual 3D representation of branch and leaf surface distributions, minimizing systematic errors due to the object–sensor relationship. The models are calibrated and validated using DHPs. Using the 3D models for simulations, their capabilities for the description of leaf density distributions and the simulation of aLiDAR and DHP signatures are shown. At an experimental test site, the suitability of the models, in order to systematically simulate and evaluate aLiDAR based LAI predictions under various scan settings is proven. This strategy makes it possible to show the importance of laser point sampling density, but also the diversity of scan angles and their quantitative effect onto error margins.

  16. Reliability and validity of a visual analogue scale used by owners to measure chronic pain attributable to osteoarthritis in their dogs.

    Science.gov (United States)

    Hielm-Björkman, Anna K; Kapatkin, Amy S; Rita, Hannu J

    2011-05-01

    To assess validity and reliability for a visual analogue scale (VAS) used by owners to measure chronic pain in their osteoarthritic dogs. 68, 61, and 34 owners who completed a questionnaire. Owners answered questionnaires at 5 time points. Criterion validity of the VAS was evaluated for all dogs in the intended-to-treat population by correlating scores for the VAS with scores for the validated Helsinki Chronic Pain Index (HCPI) and a relative quality-of-life scale. Intraclass correlation was used to assess repeatability of the pain VAS at 2 baseline evaluations. To determine sensitivity to change and face validity of the VAS, 2 blinded, randomized control groups (17 dogs receiving carprofen and 17 receiving a placebo) were analyzed over time. Significant correlations existed between the VAS score and the quality-of-life scale and HCPI scores. Intraclass coefficient (r = 0.72; 95% confidence interval, 0.57 to 0.82) for the VAS indicated good repeatability. In the carprofen and placebo groups, there was poor correlation between the 2 pain evaluation methods (VAS and HCPI items) at the baseline evaluation, but the correlation improved in the carprofen group over time. No correlation was detected for the placebo group over time. Although valid and reliable, the pain VAS was a poor tool for untrained owners because of poor face validity (ie, owners could not recognize their dogs' behavior as signs of pain). Only after owners had seen pain diminish and then return (after starting and discontinuing NSAID use) did the VAS have face validity.

  17. [Conception and Content Validation of a Questionnaire Relating to the Potential Need for Information of Visually Impaired Persons with Regard to Services and Contact Persons].

    Science.gov (United States)

    Hahn, U; Hechler, T; Witt, U; Krummenauer, F

    2015-12-01

    A questionnaire was drafted to identify the needs of visually impaired persons and to optimize their access to non-medical support and services. Subjects had to rate a list of 15 everyday activities that are typically affected by visual impairment (for example, being able to orient themselves in the home environment), by indicating the degree to which they perceive each activity to be affected, using a four-stage scale. They had to evaluate these aspects by means of a relevance assessment. The needs profile derived from this is then correlated with individualized information for assistance and support. The questionnaire shall be made available for use by subjects through advisers in some ophthalmic practices and via the internet. The validity of the content of the proposed tool was evaluated on the basis of a survey of 59 experts in the fields of medical, optical and psychological care and of persons involved in training initiatives. The experts were asked to rate the activities by relevance and clarity of the wording and to propose methods to further develop and optimize the content. The validity of the content was quantified according to a process adopted in the literature, based on the parameters Interrater Agreement (IRA) and Content Validity Index (CVI). The results of all responses (n = 19) and the sub-group analysis suggest that the questionnaire adequately reflects the potential needs profile of visually impaired persons. Overall, there was at least 80% agreement among the 19 experts for 93% of the proposed parameterisation of the activities relating to the relevance and clarity of the wording. Individual proposals for optimization of the design of the questionnaire were adopted. Georg Thieme Verlag KG Stuttgart · New York.

  18. Face validity of VIS-Ed: a visualization program for teaching medical students and residents the biomechanics of cervical spine trauma.

    Science.gov (United States)

    Courteille, Olivier; Ho, Johnson; Fahlstedt, Madelen; Fors, Uno; Felländer-Tsai, Li; Hedman, Leif; Möller, Hans

    2013-01-01

    This RCT study aimed to investigate if VIS-Ed (Visualization through Imaging and Simulation - Education) had the potential to improve medical student education and specialist training in clinical diagnosis and treatment of trauma patients. The participants' general opinion was reported as high in both groups (lecture vs. virtual patient (VP)). Face validity of the VIS-Ed for cervical spine trauma was demonstrated and the VP group reported higher stimulation and engagement compared to the lecture group. No significant difference in the knowledge test between both groups could be observed, confirming our null hypothesis that VIS-Ed was on par with a lecture.

  19. Rapid 2D phase-contrast magnetic resonance angiography reconstruction algorithm via compressed sensing

    Science.gov (United States)

    Lee, Dong-Hoon; Hong, Cheol-Pyo; Lee, Man-Woo; Han, Bong-Soo

    2013-09-01

    Phase-contrast magnetic resonance angiography (PC MRA) is an excellent technique for visualization of venous vessels. However, the scan time of PC MRA is long compared with there of other MRA techniques. Recently, the potential of compressed sensing (CS) reconstruction to reduce the scan time in MR image acquisition using a sparse sampling dataset has become an active field of study. In this study, we propose a combination method to apply the CS reconstruction method to 2D PC MRA. This work was performed to enable faster 2D PC MRA imaging acquisition and to demonstrate its feasibility. We used a 0.32 T MR imaging (MRI) system and a total variation (TV)-based CS reconstruction algorithm. To validate the usefulness of our proposed reconstruction method, we used visual assessment for reconstructed images, and we measured the quantitative information for sampling rates from 12.5 to 75.0%. Based on our results, when the sampling ratio is increased, images reconstructed with the CS method have a similar level of image quality to fully sampled reconstruction images. The signal to noise ratio (SNR) and the contrast-to-noise ratio (CNR) were also closer to the reference values when the sampling ratio was increased. We confirmed the feasibility of 2D PC MRA with the CS reconstruction method. Our results provide evidence that this method can improve the time resolution of 2D PC MRA.

  20. Assessment of pruritus intensity: prospective study on validity and reliability of the visual analogue scale, numerical rating scale and verbal rating scale in 471 patients with chronic pruritus.

    Science.gov (United States)

    Phan, Ngoc Quan; Blome, Christine; Fritz, Fleur; Gerss, Joachim; Reich, Adam; Ebata, Toshiya; Augustin, Matthias; Szepietowski, Jacek C; Ständer, Sonja

    2012-09-01

    The most commonly used tool for self-report of pruritus intensity is the visual analogue scale (VAS). Similar tools are the numerical rating scale (NRS) and verbal rating scale (VRS). In the present study, initiated by the International Forum for the Study of Itch assessing reliability of these tools, 471 randomly selected patients with chronic itch (200 males, 271 females, mean age 58.44 years) recorded their pruritus intensity on VAS (100-mm line), NRS (0-10) and VRS (four-point) scales. Re-test reliability was analysed in a subgroup of 250 patients after one hour. Statistical analysis showed a high reliability and concurrent validity (r>0.8; pscales showed a high correlation. In conclusion, high reliability and concurrent validity was found for VAS, NRS and VRS. On re-test, higher correlation and less missing values were observed. A training session before starting a clinical trial is recommended.

  1. A Multi-Data Source and Multi-Sensor Approach for the 3D Reconstruction and Web Visualization of a Complex Archaelogical Site: The Case Study of “Tolmo De Minateda”

    Directory of Open Access Journals (Sweden)

    Jose Alberto Torres-Martínez

    2016-06-01

    Full Text Available The complexity of archaeological sites hinders creation of an integral model using the current Geomatic techniques (i.e., aerial, close-range photogrammetry and terrestrial laser scanner individually. A multi-sensor approach is therefore proposed as the optimal solution to provide a 3D reconstruction and visualization of these complex sites. Sensor registration represents a riveting milestone when automation is required and when aerial and terrestrial datasets must be integrated. To this end, several problems must be solved: coordinate system definition, geo-referencing, co-registration of point clouds, geometric and radiometric homogeneity, etc. The proposed multi-data source and multi-sensor approach is applied to the study case of the “Tolmo de Minateda” archaeological site. A total extension of 9 ha is reconstructed, with an adapted level of detail, by an ultralight aerial platform (paratrike, an unmanned aerial vehicle, a terrestrial laser scanner and terrestrial photogrammetry. Finally, a mobile device (e.g., tablet or smartphone has been used to integrate, optimize and visualize all this information, providing added value to archaeologists and heritage managers who want to use an efficient tool for their works at the site, and even for non-expert users who just want to know more about the archaeological settlement.

  2. 3D visibility analysis as a tool to validate ancient theatre reconstructions: the case of the large Roman theatre of Gortyn

    Directory of Open Access Journals (Sweden)

    Maria Cristina Manzetti

    2016-11-01

    Full Text Available With the diffusion of Virtual Archaeology, many projects in the field of Cultural Heritage attempt to virtually reconstruct historical buildings of different types. Unfortunately, some of these 3D reconstructions still have as principal aim to impress the external users, while the correct interpretation of the buildings modeled is much more important in the domain of archaeological research. Still more critical is the situation when we have to encounter a reconstruction of a monument which is not visible anymore, or which consists only of few architectural remains. The main purpose of this paper is to introduce an innovative methodology to verify hypothetical scenarios of 3D architectural reconstructions, specifically for ancient theatres. In very recent time 3D visibility analysis applied to archaeological context using ArcGIS has been developed, in particular about social-urban studies. In this paper, visibility analysis in 3D contexts is used as an additional instrument to correctly reconstruct architectural elements of the large Roman theatre of Gortyn, in Crete. The results indicate that the level of visibility of the stage, and consequently of the presumed actors, from some of the more representative sectors of the cavea, is of crucial importance for leading to a right reconstruction model of the theatre.

  3. Development and Validation of a Smartphone-Based Visual Acuity Test (Peek Acuity) for Clinical Practice and Community-Based Fieldwork.

    Science.gov (United States)

    Bastawrous, Andrew; Rono, Hillary K; Livingstone, Iain A T; Weiss, Helen A; Jordan, Stewart; Kuper, Hannah; Burton, Matthew J

    2015-08-01

    Visual acuity is the most frequently performed measure of visual function in clinical practice and most people worldwide living with visual impairment are living in low- and middle-income countries. To design and validate a smartphone-based visual acuity test that is not dependent on familiarity with symbols or letters commonly used in the English language. Validation study conducted from December 11, 2013, to March 4, 2014, comparing results from smartphone-based Peek Acuity to Snellen acuity (clinical normal) charts and the Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR chart (reference standard). This study was nested within the 6-year follow-up of the Nakuru Eye Disease Cohort in central Kenya and included 300 adults aged 55 years and older recruited consecutively. Outcome measures were monocular logMAR visual acuity scores for each test: ETDRS chart logMAR, Snellen acuity, and Peek Acuity. Peek Acuity was compared, in terms of test-retest variability and measurement time, with the Snellen acuity and ETDRS logMAR charts in participants' homes and temporary clinic settings in rural Kenya in 2013 and 2014. The 95% CI limits for test-retest variability of smartphone acuity data were ±0.033 logMAR. The mean differences between the smartphone-based test and the ETDRS chart and the smartphone-based test and Snellen acuity data were 0.07 (95% CI, 0.05-0.09) and 0.08 (95% CI, 0.06-0.10) logMAR, respectively, indicating that smartphone-based test acuities agreed well with those of the ETDRS and Snellen charts. The agreement of Peek Acuity and the ETDRS chart was greater than the Snellen chart with the ETDRS chart (95% CI, 0.05-0.10; P = .08). The local Kenyan community health care workers readily accepted the Peek Acuity smartphone test; it required minimal training and took no longer than the Snellen test (77 seconds vs 82 seconds; 95% CI, 71-84 seconds vs 73-91 seconds, respectively; P = .13). The study demonstrated that the Peek Acuity smartphone

  4. Regularization Reconstruction Method for Imaging Problems in Electrical Capacitance Tomography

    Science.gov (United States)

    Chu, Pan; Lei, Jing

    2017-11-01

    The electrical capacitance tomography (ECT) is deemed to be a powerful visualization measurement technique for the parametric measurement in a multiphase flow system. The inversion task in the ECT technology is an ill-posed inverse problem, and seeking for an efficient numerical method to improve the precision of the reconstruction images is important for practical measurements. By the introduction of the Tikhonov regularization (TR) methodology, in this paper a loss function that emphasizes the robustness of the estimation and the low rank property of the imaging targets is put forward to convert the solution of the inverse problem in the ECT reconstruction task into a minimization problem. Inspired by the split Bregman (SB) algorithm, an iteration scheme is developed for solving the proposed loss function. Numerical experiment results validate that the proposed inversion method not only reconstructs the fine structures of the imaging targets, but also improves the robustness.

  5. Validity of the visual analogue scale as an instrument to measure self-efficacy in resuscitation skills

    NARCIS (Netherlands)

    Turner, Nigel M.; de Leemput, Anita J. van; Draaisma, Jos M. T.; Oosterveld, Paul; ten Cate, Olle Th J.

    CONTEXT Self-efficacy is an important factor in many areas of medical education, including self-assessment and self-directed learning, but has been little studied in resuscitation training, possibly because of the lack of a simple measurement instrument. OBJECTIVE We aimed to assess the validity of

  6. Impact of an advanced image-based monoenergetic reconstruction algorithm on coronary stent visualization using third generation dual-source dual-energy CT: a phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Mangold, Stefanie [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Cannao, Paola M. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Milan, Scuola di Specializzazione in Radiodiagnostica, Milan (Italy); Schoepf, U.J. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Wichmann, Julian L. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Canstein, Christian [Siemens Medical Solutions, Malvern, PA (United States); Fuller, Stephen R.; Varga-Szemes, Akos [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Muscogiuri, Giuseppe; De Cecco, Carlo N. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' , Department of Radiological Sciences, Oncology and Pathology, Rome (Italy); Nikolaou, Konstantin [Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany)

    2016-06-15

    To evaluate the impact of an advanced monoenergetic (ME) reconstruction algorithm on CT coronary stent imaging in a phantom model. Three stents with lumen diameters of 2.25, 3.0 and 3.5 mm were examined with a third-generation dual-source dual-energy CT (DECT). Tube potential was set at 90/Sn150 kV for DE and 70, 90 or 120 kV for single-energy (SE) acquisitions and advanced modelled iterative reconstruction was used. Overall, 23 reconstructions were evaluated for each stent including three SE acquisitions and ten advanced and standard ME images with virtual photon energies from 40 to 130 keV, respectively. In-stent luminal diameter was measured and compared to nominal lumen diameter to determine stent lumen visibility. Contrast-to-noise ratio was calculated. Advanced ME reconstructions substantially increased lumen visibility in comparison to SE for stents ≤3 mm. 130 keV images produced the best mean lumen visibility: 86 % for the 2.25 mm stent (82 % for standard ME and 64 % for SE) and 82 % for the 3.0 mm stent (77 % for standard ME and 69 % for SE). Mean DLP for SE 120 kV and DE acquisitions were 114.4 ± 9.8 and 58.9 ± 2.2 mGy x cm, respectively. DECT with advanced ME reconstructions improves the in-lumen visibility of small stents in comparison with standard ME and SE imaging. (orig.)

  7. Feasibility, validity and test-retest reliability of scaling methods for health states: the visual analogue scale and the time trade-off.

    Science.gov (United States)

    Badia, X; Monserrat, S; Roset, M; Herdman, M

    1999-06-01

    The feasibility, validity and reliability of the Time Trade-Off (TTO) and Visual Analogue Scale (VAS) methods in obtaining preference values for health states were compared in a random sample of the Spanish population (n = 294). Respondents valued 43 EuroQol-5D health states in face-to-face interviews. Convergent validity was assessed by examining the relationship between values, and the effect of sociodemographic and health variables on values was used as a means of assessing construct validity. Test-retest reliability was analysed in a subgroup of 50 respondents, using the intraclass correlation coefficient (ICC) and generalisability theory. Rates of non-response and missing data were low on both methods, though the VAS took considerably less time to administer. VAS and TTO values correlated highly (r = 0.92), though there were differences in the ordering of health states between methods, and in the number of health states rated worse than death. VAS values were compressed into a considerably smaller valuation space than TTO values. Respondents in higher educational categories assigned higher TTO values to 12 health states. Mean ICCs (95% CI) at individual level were 0.90 (0.88-0.92) and 0.84 (0.81-0.87) for the VAS and TTO, respectively. Generalisability analysis showed variance due to time to be 0 for both methods. In conclusion, the VAS was more feasible and slightly more reliable than the TTO, whilst doubt can be cast on the degree of convergent validity existing between the two methods. The compression of VAS values means that the TTO is likely to discriminate better between health states, and it may have greater construct validity if results from larger samples confirm that there are genuine differences between sociodemographic subgroups.

  8. Validation of Fourier decomposition MRI with dynamic contrast-enhanced MRI using visual and automated scoring of pulmonary perfusion in young cystic fibrosis patients

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, Grzegorz, E-mail: g.bauman@dkfz.de [German Cancer Research Center, Division of Medical Physics in Radiology, Im Neuenheimer Feld 223, 69120 Heidelberg (Germany); Puderbach, Michael, E-mail: m.puderbach@dkfz.de [Chest Clinics at the University of Heidelberg, Clinics for Interventional and Diagnostic Radiology, Amalienstr. 5, 69126 Heidelberg (Germany); Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (Germany); Heimann, Tobias, E-mail: t.heimann@dkfz.de [German Cancer Research Center, Division of Medical and Biological Informatics, Im Neuenheimer Feld 223, 69120 Heidelberg (Germany); Kopp-Schneider, Annette, E-mail: kopp@dkfz.de [German Cancer Research Center, Division of Biostatistics, Im Neuenheimer Feld 223, 69120 Heidelberg (Germany); Fritzsching, Eva, E-mail: eva.fritzsching@med.uni-heidelberg.de [University Hospital Heidelberg, Department of Translational Pulmonology and Division of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center, Im Neuenheimer Feld 430, Heidelberg (Germany); Mall, Marcus A., E-mail: marcus.mall@med.uni-heidelberg.de [Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (Germany); University Hospital Heidelberg, Department of Translational Pulmonology and Division of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center, Im Neuenheimer Feld 430, Heidelberg (Germany); Eichinger, Monika, E-mail: m.eichinger@dkfz.de [Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (Germany); German Cancer Research Center, Division of Radiology, Im Neuenheimer Feld 223, 69120 Heidelberg (Germany)

    2013-12-01

    Purpose: To validate Fourier decomposition (FD) magnetic resonance (MR) imaging in cystic fibrosis (CF) patients with dynamic contrast-enhanced (DCE) MR imaging. Materials and methods: Thirty-four CF patients (median age 4.08 years; range 0.16–30) were examined on a 1.5-T MR imager. For FD MR imaging, sets of lung images were acquired using an untriggered two-dimensional balanced steady-state free precession sequence. Perfusion-weighted images were obtained after correction of the breathing displacement and Fourier analysis of the cardiac frequency from the time-resolved data sets. DCE data sets were acquired with a three-dimensional gradient echo sequence. The FD and DCE images were visually assessed for perfusion defects by two readers independently (R1, R2) using a field based scoring system (0–12). Software was used for perfusion impairment evaluation (R3) of segmented lung images using an automated threshold. Both imaging and evaluation methods were compared for agreement and tested for concordance between FD and DCE imaging. Results: Good or acceptable intra-reader agreement was found between FD and DCE for visual and automated scoring: R1 upper and lower limits of agreement (ULA, LLA): 2.72, −2.5; R2: ULA, LLA: ±2.5; R3: ULA: 1.5, LLA: −2. A high concordance was found between visual and automated scoring (FD: 70–80%, DCE: 73–84%). Conclusions: FD MR imaging provides equivalent diagnostic information to DCE MR imaging in CF patients. Automated assessment of regional perfusion defects using FD and DCE MR imaging is comparable to visual scoring but allows for percentage-based analysis.

  9. A feasibility study for compressed sensing combined phase contrast MR angiography reconstruction

    Science.gov (United States)

    Lee, Dong-Hoon; Hong, Cheol-Pyo; Lee, Man-Woo; Han, Bong-Soo

    2012-02-01

    Phase contrast magnetic resonance angiography (PC MRA) is a technique for flow velocity measurement and vessels visualization, simultaneously. The PC MRA takes long scan time because each flow encoding gradients which are composed bipolar gradient type need to reconstruct the angiography image. Moreover, it takes more image acquisition time when we use the PC MRA at the low-tesla MRI system. In this study, we studied and evaluation of feasibility for CS MRI reconstruction combined PC MRA which data acquired by low-tesla MRI system. We used non-linear reconstruction algorithm which named Bregman iteration for CS image reconstruction and validate the usefulness of CS combined PC MRA reconstruction technique. The results of CS reconstructed PC MRA images provide similar level of image quality between fully sampled reconstruction data and sparse sampled reconstruction using CS technique. Although our results used half of sampling ratio and do not used specification hardware device or performance which are improving the temporal resolution of MR image acquisition such as parallel imaging reconstruction using phased array coil or non-cartesian trajectory, we think that CS combined PC MRA technique will be helpful to increase the temporal resolution and at low-tesla MRI system.

  10. A validation study to find highly correlated parameters with visual assessment for clinical evaluation of cosmetic anti-cellulite products.

    Science.gov (United States)

    Yoo, Mi Ae; Seo, Young Kyoung; Ryu, Ja Hyun; Back, Ji Hwoon; Koh, Jae Sook

    2014-05-01

    There has been growing interest in cellulite on parts of the body; however, no objective assessment has been specifically established. This study aims to demonstrate an optimized method by comparing the existing assessments of cellulite. In Test 1, for subjects of 20 healthy females who have cellulite, we measured volume and roughness of cellulite using fringe projection method, roughness using replica method, dermo-subcutaneous interface length and subcutaneous thickness using ultrasonography and skin temperature using infrared ray, elasticity and blood flow. In Test 2, we applied an anti-cellulite cosmetic to 28 subjects for 6 weeks and observed if they have any changes. In Test 1, the effective parameter that is the most correlated with visual assessment was volume of skin measured using fringe projection method (r = 0.780). Dermo-subcutaneous interface length (r = 0.355) and subcutaneous thickness (r = 0.502) measured using ultrasonography followed in order. In Test 2, after applying a tested product, the correlation coefficient of volume of skin, of dermo-subcutaneous interface length and of subcutaneous thickness are 0.409 (P = 0.000), 0.275 (P = 0.016) and 0.311 (P = 0.012) respectively. We conclude that visual assessment, volume of skin (cavities), dermo-subcutaneous interface length and subcutaneous thickness are optimized methods for assessing an effect of cosmetics on cellulite. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Accuracy, Validity, and Reliability of an Electronic Visual Analog Scale for Pain on a Touch Screen Tablet in Healthy Older Adults: A Clinical Trial.

    Science.gov (United States)

    Bird, Marie-Louise; Callisaya, Michele L; Cannell, John; Gibbons, Timothy; Smith, Stuart T; Ahuja, Kiran Dk

    2016-01-14

    New technology for clinical data collection is rapidly evolving and may be useful for both researchers and clinicians; however, this new technology has not been tested for accuracy, reliability, or validity. This study aims to test the accuracy of visual analog scale (VAS) for pain on a newly designed application on the iPad (iPadVAS) and measure the reliability and validity of iPadVAS compared to a paper copy (paperVAS). Accuracy was determined by physically measuring an iPad scale on screen and comparing it to the results from the program, with a researcher collecting 101 data points. A total of 22 healthy community dwelling older adults were then recruited to test reliability and validity. Each participant completed 8 VAS (4 using each tool) in a randomized order. Reliability was measured using interclass correlation coefficient (ICC) and validity measured using Bland-Altman graphs and correlations. Of the measurements for accuracy, 64 results were identical, 2 results were manually measured as being 1 mm higher than the program, and 35 as 1 mm lower. Reliability for the iPadVAS was excellent with individual ICC 0.90 (95% CI 0.82-0.95) and averaged ICC 0.97 (95% CI 0.95-1.0) observed. Linear regression demonstrated a strong relationship with a small negative bias towards the iPad (-2.6, SD 5.0) with limits of agreement from -12.4 to 7.1. The iPadVAS provides a convenient, user-friendly, and efficient way of collecting data from participants in measuring their current pain levels. It has potential use in documentation management and may encourage participatory healthcare. Australia New Zealand Clinical Trials Registry (ANZCTR): 367297; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=367297&isReview=true (Archived by Webcite at http://www.webcitation.org/6d9xYoUbD).

  12. Measuring individual hierarchy of anxiety invoking sports related activities: development and validation of the Photographic Series of Sports Activities for Anterior Cruciate Ligament Reconstruction (PHOSA-ACLR)

    NARCIS (Netherlands)

    Lankveld, W. van; Melick, N. van; Habets, B.; Roelofsen, E.; Staal, J.B.; Cingel, R.E. van

    2017-01-01

    BACKGROUND: Fear of harm (FoH) after Anterior Cruciate Ligament Reconstruction (ACLR) should be addressed in physical therapy as it hampers return to sports. However, there are no instruments assessing FoH specific for ACLR. The objective of this study is to describe the development and measurement

  13. Pre-validation of an in vitro skin irritation test for medical devices using the reconstructed human tissue model EpiDerm™.

    NARCIS (Netherlands)

    Kandarova, Helena; Willoughby, Jamin A; De Jong, Wim H; Letasiova, Silvia; Milasova, Tatiana; Bachelor, Michael A; Breyfogle, Bridget; Handa, Yuki; De la Fonteyne, Liset; Coleman, Kelly P

    2018-01-01

    Assessment of dermal irritation is an essential component of the safety evaluation of medical devices. Reconstructed human epidermis (RhE) models have replaced rabbit skin irritation testing for neat chemicals and their mixtures (OECD Test Guideline 439). However, this guideline cannot be directly

  14. Designing and Evaluation of Reliability and Validity of Visual Cue-Induced Craving Assessment Task for Methamphetamine Smokers

    Directory of Open Access Journals (Sweden)

    Hamed Ekhtiari

    2010-08-01

    Full Text Available A B S T R A C TIntroduction: Craving to methamphetamine is a significant health concern and exposure to methamphetamine cues in laboratory can induce craving. In this study, a task designing procedure for evaluating methamphetamine cue-induced craving in laboratory conditions is examined. Methods: First a series of visual cues which could induce craving was identified by 5 discussion sessions between expert clinicians and 10 methamphetamine smokers. Cues were categorized in 4 main clusters and photos were taken for each cue in studio, then 60 most evocative photos were selected and 10 neutral photos were added. In this phase, 50 subjects with methamphetamine dependence, had exposure to cues and rated craving intensity induced by the 72 cues (60 active evocative photos + 10 neutral photos on self report Visual Analogue Scale (ranging from 0-100. In this way, 50 photos with high levels of evocative potency (CICT 50 and 10 photos with the most evocative potency (CICT 10 were obtained and subsequently, the task was designed. Results: The task reliability (internal consistency was measured by Cronbach’s alpha which was 91% for (CICT 50 and 71% for (CICT 10. The most craving induced was reported for category Drug use procedure (66.27±30.32 and least report for category Cues associated with drug use (31.38±32.96. Difference in cue-induced craving in (CICT 50 and (CICT 10 were not associated with age, education, income, marital status, employment and sexual activity in the past 30 days prior to study entry. Family living condition was marginally correlated with higher scores in (CICT 50. Age of onset for (opioids, cocaine and methamphetamine was negatively correlated with (CICT 50 and (CICT 10 and age of first opiate use was negatively correlated with (CICT 50. Discussion: Cue-induced craving for methamphetamine may be reliably measured by tasks designed in laboratory and designed assessment tasks can be used in cue reactivity paradigm, and

  15. Validity and Reliability of Visual Analog Scaling for Assessment of Hypernasality and Audible Nasal Emission in Children With Repaired Cleft Palate.

    Science.gov (United States)

    Baylis, Adriane; Chapman, Kathy; Whitehill, Tara L; Group, The Americleft Speech

    2015-11-01

    To investigate the validity and reliability of multiple listener judgments of hypernasality and audible nasal emission, in children with repaired cleft palate, using visual analog scaling (VAS) and equal-appearing interval (EAI) scaling. Prospective comparative study of multiple listener ratings of hypernasality and audible nasal emission. Multisite institutional. Five trained and experienced speech-language pathologist listeners from the Americleft Speech Project. Average VAS and EAI ratings of hypernasality and audible nasal emission/turbulence for 12 video-recorded speech samples from the Americleft Speech Project. Intrarater and interrater reliability was computed, as well as linear and polynomial models of best fit. Intrarater and interrater reliability was acceptable for both rating methods; however, reliability was higher for VAS as compared to EAI ratings. When VAS ratings were plotted against EAI ratings, results revealed a stronger curvilinear relationship. The results of this study provide additional evidence that alternate rating methods such as VAS may offer improved validity and reliability over EAI ratings of speech. VAS should be considered a viable method for rating hypernasality and nasal emission in speech in children with repaired cleft palate.

  16. Assessing fibromyalgia-related fatigue: content validity and psychometric performance of the Fatigue Visual Analog Scale in adult patients with fibromyalgia.

    Science.gov (United States)

    Crawford, B K; Piault, E C; Lai, C; Bennett, R M

    2011-01-01

    To document 1) the content validity and 2) measure improvements in fatigue, using the Fatigue Visual Analogue Scale (VAS) assessment tool in patients with fibromyalgia. The relevance and comprehensiveness of the Fatigue VAS were tested through a qualitative analysis of 20 subjects' verbatim transcripts from semi-structured qualitative interviews. Data from two randomised, controller trials in fibromyalgia (n=1121) were used to conduct correlation analyses with the Fatigue and Tiredness items from the Fibromyalgia Impact Questionnaire (FIQ) and the Short Form-36 Vitality scale. Known-groups and cross classification analyses were conducted to demonstrate the ability to measure improvement in fatigue using the Fatigue VAS. All subjects spontaneously reported that fatigue was an important symptom to capture in fibromyalgia. The Fatigue VAS was well understood by most subjects (n=18/20). High correlations (Pearson r>0.75) and good agreement (k>0.66) were found between the Fatigue VAS and the FIQ tiredness items no. 16 and 17 and SF-36™ Vitality scale. In both clinical trials there was a substantial separation of approximately 20 points on the mean change in the Fatigue VAS score between responders (>30% improvement in pain VAS) and non-responders. Previous studies have confirmed that fatigue is a major component of the fibromyalgia experience. This current study reports that fibromyalgia patients spontaneously rated fatigue as a highly significant feature of their illness, and supports the use of the Fatigue VAS as a valid questionnaire in fibromyalgia clinical trials.

  17. Relative efficiency and validity properties of a visual analogue vs a categorical scaled version of the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index: Spanish versions.

    Science.gov (United States)

    Villanueva, I; del Mar Guzman, M; Javier Toyos, F; Ariza-Ariza, R; Navarro, F

    2004-03-01

    To compare the performance of visual analogue (VAS) vs categorical (CT) scaled versions of the three subscales (pain, stiffness and difficulty) of the WOMAC Index in patients with knee osteoarthritis. Patients with knee OA (at least grade II of Kellgren & Lawrence classification) were treated for a 6-weeks period with an NSAID. The following measures were applied at baseline and after treatment: VAS and CT WOMAC scales, Lequesne Index, pain on VAS, and global assessment by patient and observer. Construct Validity was determined by correlation of each of the subscale scores with the other outcomes both at baseline and after treatment (Pearson's test); responsiveness comparing baseline vs final status by Wilcoxon's test; reliability by analysis of the internal consistency using Cronbach's alpha at baseline and after the treatment period; and test-retest reliability by Kendall's Tau-c statistics. Finally, correlation and analysis of the relative efficiency (RE) between the subscales of both formats were tested. Seventy-three (8 men and 65 women) patients with a mean disease duration from first diagnosis of 69 months (3 to 254) completed the study. The following were the observed values for the instruments' psychometric properties: (1) construct validity: correlations ranged from 0.30 to 0.84 for VAS and 0.27 to 0.77 for CT subscales; (2) responsiveness: achieved P values for the pain, stiffness and difficulty scales were Pscales in VAS format and the stiffness scale in CT format to have a slightly better performance in this sample.

  18. Convergent validity of the measures of attention and impulsivity in the Trees: simple Visual Discrimination Test (DiViSA-UAM

    Directory of Open Access Journals (Sweden)

    José H. Lozano

    2015-01-01

    Full Text Available The Trees: Simple Visual Discrimination Test (DiViSA-UAM is an objective test to assess attention and impulsivity in children aged between 6 and 12 years. The aim of this study was to supplement the validity data obtained in prior research, analyzing the evidence of convergent validity of the measures of the DiViSA-UAM in relation to other, already well-established, instruments for assessing attention and inhibitory control in children: the 'Faces', Differences Perception Test and the d2 Test of Attention. To this end, the instruments were administered to a sample of 111 students from primary education (46 girls and 65 boys between the ages of 8 and 12 years. The correlation analysis showed values in line with expectations among the indices of the three tests. Similarly to what has been observed in prior research, the three tests coincided in identifying a progressive increase in attention performance between the ages of 8 and 12, as well as stability in impulsivity control and the absence of sex-related differences. We discuss the potential advantages of the DiViSA-UAM derived from its application format and its greater ease of execution.

  19. Comparison of the construct validity and sensitivity to change of the visual analog scale and a modified rating scale as measures of patient global assessment in rheumatoid arthritis.

    Science.gov (United States)

    Lati, Chili; Guthrie, Lori C; Ward, Michael M

    2010-04-01

    Patient global assessment (PGA) is commonly measured using a visual analog scale (VAS). The VAS asks patients to integrate many dimensions of rheumatoid arthritis (RA) activity, yet its scope is poorly defined and its endpoints are vague. We investigated whether a modified Rating Scale that used marker states and more defined endpoints would provide a more valid measure of PGA. In our prospective longitudinal study, 164 patients with active RA rated their global arthritis activity using the VAS and Rating Scale before and after treatment. To compare construct validity, we correlated each score with 2 reference measures of RA activity, the 28-joint count Disease Activity Score (DAS28) and the physician global assessment, and examined how each measure was associated with different aspects of RA activity, including pain, functioning, and depressive symptoms, in multivariate regression analyses. We also examined sensitivity to change. Both measures were correlated with the DAS28 (r = 0.39 for VAS; r = 0.35 for Rating Scale) and physician global assessment (r = 0.41 for VAS; r = 0.26 for Rating Scale) at the baseline visit. Pain and depressive symptoms had the strongest association with the VAS, while functional limitations and depressive symptoms had the strongest association with the Rating Scale. Residual analysis showed no differences in heterogeneity of patients' ratings. VAS was more sensitive to change than the Rating Scale (standardized response means of 0.55 and 0.45). As measures of PGA, the VAS and Rating Scale had comparable construct validity, but differed in which aspects of arthritis activity influenced scores. VAS was more sensitive to change.

  20. Is a single-item visual analogue scale as valid, reliable and responsive as multi-item scales in measuring quality of life?

    Science.gov (United States)

    de Boer, A G E M; van Lanschot, J J B; Stalmeier, P F M; van Sandick, J W; Hulscher, J B F; de Haes, J C J M; Sprangers, M A G

    2004-03-01

    To compare the validity, reliability and responsiveness of a single, global quality of life question to multi-item scales. Data were obtained from 83 consecutive patients with oesophageal adenocarcinoma undergoing either transhiatal or transthoracic oesophagectomy. Quality of life was measured at baseline, 5 weeks, 3 and 12 months post-operatively with a single-item Visual Analogue Scale (VAS) ranging from 0 to 100, the multi-item Medical Outcomes Study Short Form-20 (MOS SF-20) and Rotterdam Symptom Check-List (RSCL). Convergent and discriminant validity, test-retest reliability and both distribution-based and anchor-based responsiveness were evaluated. At baseline and at 5 weeks, the VAS showed high correlations with the MOS SF-20 health perceptions scale (r = 0.70 and 0.72) and moderate to high correlations with all other subscales of the MOS SF-20 and RSCL (r = 0.29-0.70). The test-retest reliability intra-class correlation for the VAS was 0.87. At 5 weeks post-operatively, the distribution-based responsiveness was moderate for the VAS (standardised response mean: -0.47; effect size: -0.56), high for the physical subscales of the MOS SF-20 and RSCL (-1.08 to -1.51) and low for the psychological subscales (0.11 to -0.25). Five weeks post-operatively, anchor-based responsiveness was highest for the VAS (r = 0.54). The VAS is an instrument with good validity, excellent reliability, moderate distribution-based responsiveness and good anchor-based responsiveness compared to multi-item questionnaires. Its use is recommended in clinical trials to assess global quality of life.

  1. Improved coronary in-stent visualization using a combined high-resolution kernel and a hybrid iterative reconstruction technique at 256-slice cardiac CT-Pilot study.

    Science.gov (United States)

    Oda, Seitaro; Utsunomiya, Daisuke; Funama, Yoshinori; Takaoka, Hiroko; Katahira, Kazuhiro; Honda, Keiichi; Noda, Katsuo; Oshima, Shuichi; Yamashita, Yasuyuki

    2013-02-01

    To investigate the diagnostic performance of 256-slice cardiac CT for the evaluation of the in-stent lumen by using a hybrid iterative reconstruction (HIR) algorithm combined with a high-resolution kernel. This study included 28 patients with 28 stents who underwent cardiac CT. Three different reconstruction images were obtained with: (1) a standard filtered back projection (FBP) algorithm with a standard cardiac kernel (CB), (2) an FBP algorithm with a high-resolution cardiac kernel (CD), and (3) an HIR algorithm with the CD kernel. We measured image noise and kurtosis and used receiver operating characteristics analysis to evaluate observer performance in the detection of in-stent stenosis. Image noise with FBP plus the CD kernel (80.2 ± 15.5 HU) was significantly higher than with FBP plus the CB kernel (28.8 ± 4.6 HU) and HIR plus the CD kernel (36.1 ± 6.4 HU). There was no significant difference in the image noise between FBP plus the CB kernel and HIR plus the CD kernel. Kurtosis was significantly better with the CD- than the CB kernel. The kurtosis values obtained with the CD kernel were not significantly different between the FBP- and HIR reconstruction algorithms. The areas under the receiver operating characteristics curves with HIR plus the CD kernel were significantly higher than with FBP plus the CB- or the CD kernel. The difference between FBP plus the CB- or the CD kernel was not significant. The average sensitivity, specificity, and positive and negative predictive value for the detection of in-stent stenosis were 83.3, 50.0, 33.3, and 91.6% for FBP plus the CB kernel, 100, 29.6, 40.0, and 100% for FBP plus the CD kernel, and 100, 54.5, 40.0, and 100% for HIR plus the CD kernel. The HIR algorithm combined with the high-resolution kernel significantly improved diagnostic performance in the detection of in-stent stenosis. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  2. Improved coronary in-stent visualization using a combined high-resolution kernel and a hybrid iterative reconstruction technique at 256-slice cardiac CT—Pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Oda, Seitaro, E-mail: seisei0430@nifty.com [Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Kumamoto 860-8556 (Japan); Utsunomiya, Daisuke, E-mail: utsunomi@kumamoto-u.ac.jp [Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Kumamoto 860-8556 (Japan); Funama, Yoshinori, E-mail: funama@kumamoto-u.ac.jp [Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Kumamoto 860-8556 (Japan); Takaoka, Hiroko, E-mail: hiroko_takayoka@yahoo.co.jp [Department of Diagnostic Radiology, Kumamoto Chuo Hospital, 1-5-1 Tainoshima, Kumamoto 862-0965 (Japan); Katahira, Kazuhiro, E-mail: yy26kk@yahoo.co.jp [Department of Diagnostic Radiology, Kumamoto Chuo Hospital, 1-5-1 Tainoshima, Kumamoto 862-0965 (Japan); Honda, Keiichi, E-mail: k-book@osu.bbiq.jp [Department of Diagnostic Radiology, Kumamoto Chuo Hospital, 1-5-1 Tainoshima, Kumamoto 862-0965 (Japan); Noda, Katsuo, E-mail: k-noda@kumachu.gr.jp [Department of Cardiology, Kumamoto Chuo Hospital, 1-5-1 Tainoshima, Kumamoto 862-0965 (Japan); Oshima, Shuichi, E-mail: shuoshima@e-mail.jp [Department of Cardiology, Kumamoto Chuo Hospital, 1-5-1 Tainoshima, Kumamoto 862-0965 (Japan); Yamashita, Yasuyuki, E-mail: yama@kumamoto-u.ac.jp [Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Kumamoto 860-8556 (Japan)

    2013-02-15

    Objectives: To investigate the diagnostic performance of 256-slice cardiac CT for the evaluation of the in-stent lumen by using a hybrid iterative reconstruction (HIR) algorithm combined with a high-resolution kernel. Methods: This study included 28 patients with 28 stents who underwent cardiac CT. Three different reconstruction images were obtained with: (1) a standard filtered back projection (FBP) algorithm with a standard cardiac kernel (CB), (2) an FBP algorithm with a high-resolution cardiac kernel (CD), and (3) an HIR algorithm with the CD kernel. We measured image noise and kurtosis and used receiver operating characteristics analysis to evaluate observer performance in the detection of in-stent stenosis. Results: Image noise with FBP plus the CD kernel (80.2 ± 15.5 HU) was significantly higher than with FBP plus the CB kernel (28.8 ± 4.6 HU) and HIR plus the CD kernel (36.1 ± 6.4 HU). There was no significant difference in the image noise between FBP plus the CB kernel and HIR plus the CD kernel. Kurtosis was significantly better with the CD- than the CB kernel. The kurtosis values obtained with the CD kernel were not significantly different between the FBP- and HIR reconstruction algorithms. The areas under the receiver operating characteristics curves with HIR plus the CD kernel were significantly higher than with FBP plus the CB- or the CD kernel. The difference between FBP plus the CB- or the CD kernel was not significant. The average sensitivity, specificity, and positive and negative predictive value for the detection of in-stent stenosis were 83.3, 50.0, 33.3, and 91.6% for FBP plus the CB kernel, 100, 29.6, 40.0, and 100% for FBP plus the CD kernel, and 100, 54.5, 40.0, and 100% for HIR plus the CD kernel. Conclusions: The HIR algorithm combined with the high-resolution kernel significantly improved diagnostic performance in the detection of in-stent stenosis.

  3. Modeling and evaluating user behavior in exploratory visual analysis

    Energy Technology Data Exchange (ETDEWEB)

    Reda, Khairi; Johnson, Andrew E.; Papka, Michael E.; Leigh, Jason

    2016-07-25

    Empirical evaluation methods for visualizations have traditionally focused on assessing the outcome of the visual analytic process as opposed to characterizing how that process unfolds. There are only a handful of methods that can be used to systematically study how people use visualizations, making it difficult for researchers to capture and characterize the subtlety of cognitive and interaction behaviors users exhibit during visual analysis. To validate and improve visualization design, however, it is important for researchers to be able to assess and understand how users interact with visualization systems under realistic scenarios. This paper presents a methodology for modeling and evaluating the behavior of users in exploratory visual analysis. We model visual exploration using a Markov chain process comprising transitions between mental, interaction, and computational states. These states and the transitions between them can be deduced from a variety of sources, including verbal transcripts, videos and audio recordings, and log files. This model enables the evaluator to characterize the cognitive and computational processes that are essential to insight acquisition in exploratory visual analysis, and reconstruct the dynamics of interaction between the user and the visualization system. We illustrate this model with two exemplar user studies, and demonstrate the qualitative and quantitative analytical tools it affords.

  4. Quantitative validation of a visual rating scale for frontal atrophy: associations with clinical status, APOE e4, CSF biomarkers and cognition.

    Science.gov (United States)

    Ferreira, Daniel; Cavallin, Lena; Granberg, Tobias; Lindberg, Olof; Aguilar, Carlos; Mecocci, Patrizia; Vellas, Bruno; Tsolaki, Magda; Kłoszewska, Iwona; Soininen, Hilkka; Lovestone, Simon; Simmons, Andrew; Wahlund, Lars-Olof; Westman, Eric

    2016-08-01

    To validate a visual rating scale of frontal atrophy with quantitative imaging and study its association with clinical status, APOE ε4, CSF biomarkers, and cognition. The AddNeuroMed and ADNI cohorts were combined giving a total of 329 healthy controls, 421 mild cognitive impairment patients, and 286 Alzheimer's disease (AD) patients. Thirty-four patients with frontotemporal dementia (FTD) were also included. Frontal atrophy was assessed with the frontal sub-scale of the global cortical atrophy scale (GCA-F) on T1-weighted images. Automated imaging markers of cortical volume, thickness, and surface area were evaluated. Manual tracing was also performed. The GCA-F scale reliably reflects frontal atrophy, with orbitofrontal, dorsolateral, and motor cortices being the regions contributing most to the GCA-F ratings. GCA-F primarily reflects reductions in cortical volume and thickness, although it was able to detect reductions in surface area too. The scale showed significant associations with clinical status and cognition. The GCA-F scale may have implications for clinical practice as supportive diagnostic tool for disorders demonstrating predominant frontal atrophy such as FTD and the executive presentation of AD. We believe that GCA-F is feasible for use in clinical routine for the radiological assessment of dementia and other disorders. • The GCA-F visual rating scale reliably reflects frontal brain atrophy. • Orbitofrontal, dorsolateral, and motor cortices are the most contributing regions. • GCA-F shows significant associations with clinical status and cognition. • GCA-F may be supportive diagnostic tool for disorders demonstrating predominant frontal atrophy. • GCA-F may be feasible for use in radiological routine.

  5. Dynamical and Mechanistic Reconstructive Approaches of T Lymphocyte Dynamics: Using Visual Modeling Languages to Bridge the Gap between Immunologists, Theoreticians, and Programmers.

    Science.gov (United States)

    Thomas-Vaslin, Véronique; Six, Adrien; Ganascia, Jean-Gabriel; Bersini, Hugues

    2013-10-01

    Dynamic modeling of lymphocyte behavior has primarily been based on populations based differential equations or on cellular agents moving in space and interacting each other. The final steps of this modeling effort are expressed in a code written in a programing language. On account of the complete lack of standardization of the different steps to proceed, we have to deplore poor communication and sharing between experimentalists, theoreticians and programmers. The adoption of diagrammatic visual computer language should however greatly help the immunologists to better communicate, to more easily identify the models similarities and facilitate the reuse and extension of existing software models. Since immunologists often conceptualize the dynamical evolution of immune systems in terms of "state-transitions" of biological objects, we promote the use of unified modeling language (UML) state-transition diagram. To demonstrate the feasibility of this approach, we present a UML refactoring of two published models on thymocyte differentiation. Originally built with different modeling strategies, a mathematical ordinary differential equation-based model and a cellular automata model, the two models are now in the same visual formalism and can be compared.

  6. Dynamical and mechanistic reconstructive approaches of T lymphocyte dynamics :Using visual modelling languages to bridge the gap between immunologists, theoreticians and programmers

    Directory of Open Access Journals (Sweden)

    Véronique eTHOMAS-VASLIN

    2013-10-01

    Full Text Available Dynamic modelling of lymphocyte behaviour has primarily been based on populations based differential equations or on cellular agents moving in space, and interacting each other. The final steps of this modelling effort are expressed in a code written in a programming language. On account of the complete lack of standardization of the different steps to proceed, we have to deplore poor communication and sharing between experimentalists, theoreticians and programmers. The adoption of diagrammatic visual computer language should however greatly help the immunologists to better communicate, to more easily identify the models similarities and facilitate the reuse and extension of existing software models. Since immunologists often conceptualize the dynamical evolution of immune systems in terms of state-transitions of biological objects, we promote the use of Unified Modelling Language (UML state-transition diagram. To demonstrate the feasibility of this approach, we present a UML refactoring of two published models on thymocyte differentiation. Originally built with different modelling strategies a mathematical ODE-based model and a cellular automata model, the two models are now in the same visual formalism and can be compared.

  7. Oblique reconstructions in tomosynthesis. II. Super-resolution

    Energy Technology Data Exchange (ETDEWEB)

    Acciavatti, Raymond J.; Maidment, Andrew D. A. [Department of Radiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104-4206 (United States)

    2013-11-15

    Purpose: In tomosynthesis, super-resolution has been demonstrated using reconstruction planes parallel to the detector. Super-resolution allows for subpixel resolution relative to the detector. The purpose of this work is to develop an analytical model that generalizes super-resolution to oblique reconstruction planes.Methods: In a digital tomosynthesis system, a sinusoidal test object is modeled along oblique angles (i.e., “pitches”) relative to the plane of the detector in a 3D divergent-beam acquisition geometry. To investigate the potential for super-resolution, the input frequency is specified to be greater than the alias frequency of the detector. Reconstructions are evaluated in an oblique plane along the extent of the object using simple backprojection (SBP) and filtered backprojection (FBP). By comparing the amplitude of the reconstruction against the attenuation coefficient of the object at various frequencies, the modulation transfer function (MTF) is calculated to determine whether modulation is within detectable limits for super-resolution. For experimental validation of super-resolution, a goniometry stand was used to orient a bar pattern phantom along various pitches relative to the breast support in a commercial digital breast tomosynthesis system.Results: Using theoretical modeling, it is shown that a single projection image cannot resolve a sine input whose frequency exceeds the detector alias frequency. The high frequency input is correctly visualized in SBP or FBP reconstruction using a slice along the pitch of the object. The Fourier transform of this reconstructed slice is maximized at the input frequency as proof that the object is resolved. Consistent with the theoretical results, experimental images of a bar pattern phantom showed super-resolution in oblique reconstructions. At various pitches, the highest frequency with detectable modulation was determined by visual inspection of the bar patterns. The dependency of the highest

  8. The perioperative validity of the visual analog anxiety scale in children: a discriminant and useful instrument in routine clinical practice to optimize postoperative pain management.

    Science.gov (United States)

    Bringuier, Sophie; Dadure, Christophe; Raux, Olivier; Dubois, Amandine; Picot, Marie-Christine; Capdevila, Xavier

    2009-09-01

    Because children's anxiety influences pain perception, perioperative anxiety should be evaluated in clinical practice with a unique, useful, and valid tool to optimize pain management. In this study, we evaluated psychometric properties of the visual analog scale (VAS)-anxiety for children and to study its perioperative relevance in clinical practice. One hundred children scheduled for elective surgery and general anesthesia were included. VAS-anxiety was measured at four timepoints and compared with both versions of State Spielbergers' questionnaires (State-Trait Anxiety Inventory for Youth [STAIY] and State-Trait Anxiety Inventory for Children [STAIC]) and the modified Yale Preoperative Anxiety Scale. Children's pain, parents' anxiety, and parents' proxy report of children's anxiety were evaluated using VAS. The correlation between STAIC and VAS-anxiety was significant on the day of discharge. Moreover, changes over time were not significant with STAIC, whereas VAS-anxiety was significantly sensitive to changes over time in the two groups of age (7-11 yr and 12-16 yr). A receiver operating characteristic curve, using modified Yale Preoperative Anxiety Scale as reference, determined a VAS-anxiety cutoff at 30 to identify high-anxiety groups. Pain levels were significantly higher when children were anxious (VAS > or = 30) in the postoperative period. Moreover, children's anxiety and pain were higher when parents were anxious. VAS-anxiety is a useful and valid tool to assess perioperative anxiety in children aged 7-16 yr. The influence of children's and parents' anxiety on children's postoperative pain suggests that VAS-anxiety should be recommended routinely for postoperative clinical practice to optimize anxiety and pain management.

  9. Use of international data sets to evaluate and validate pathway assessment models applicable to exposure and dose reconstruction at DOE facilities. Monthly progress reports and final report, October--December 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, F.O. [Senes Oak Ridge, Inc., TN (United States). Center for Risk Analysis

    1995-04-01

    The objective of Task 7.lD was to (1) establish a collaborative US-USSR effort to improve and validate our methods of forecasting doses and dose commitments from the direct contamination of food sources, and (2) perform experiments and validation studies to improve our ability to predict rapidly and accurately the long-term internal dose from the contamination of agricultural soil. At early times following an accident, the direct contamination of pasture and food stuffs, particularly leafy vegetation and grain, can be of great importance. This situation has been modeled extensively. However, models employed then to predict the deposition, retention and transport of radionuclides in terrestrial environments employed concepts and data bases that were more than a decade old. The extent to which these models have been tested with independent data sets was limited. The data gathered in the former-USSR (and elsewhere throughout the Northern Hemisphere) offered a unique opportunity to test model predictions of wet and dry deposition, agricultural foodchain bioaccumulation, and short- and long-term retention, redistribution, and resuspension of radionuclides from a variety of natural and artificial surfaces. The current objective of this project is to evaluate and validate pathway-assessment models applicable to exposure and dose reconstruction at DOE facilities through use of international data sets. This project incorporates the activity of Task 7.lD into a multinational effort to evaluate models and data used for the prediction of radionuclide transfer through agricultural and aquatic systems to humans. It also includes participation in two studies, BIOMOVS (BIOspheric MOdel Validation Study) with the Swedish National Institute for Radiation Protection and VAMP (VAlidation of Model Predictions) with the International Atomic Energy Agency, that address testing the performance of models of radionuclide transport through foodchains.

  10. Validation study to demonstrate the equivalence of a minor modification (TECRA ULTIMA protocol) to AOAC Method 998.09 (TECRA Salmonella Visual Immunoassay) with the cultural reference method.

    Science.gov (United States)

    Briggs, Julie; Dailianis, Angela; Hughes, Denise; Garthwaite, Ian

    2004-01-01

    The TECRA Salmonella Visual Immunoassay (VIA) using Rappaport-Vassiliadis RV[R10] as a single selective enrichment broth has Final Action approval (AOAC Method 998.09). TECRA has recently developed a protocol (TECRA ULTIMA), which involves the addition of a new additive to a 1 mL aliquot of the RV[R10] broth, prior to the heat-killing step, thereby allowing the RV[R10] broth to be tested directly in the kit and thus eliminating the need for the 2 h post-enrichment in M broth. An in-house validation study was conducted to compare the modified AOAC Method 998.09 to the reference culture method. Three foods were used in the study: Naturally contaminated raw ground poultry at high (10-50 cells/25 g), and low (1-5 cells/25 g) levels; and milk powder and peanut butter, artificially inoculated at low and high levels with Salmonella bovismorbificans and S. enterica Mbandaka, respectively. Twenty test portions were analyzed for each level with 10 uninoculated control samples per food. Overall, no significant differences (p analysis of RV[R10] broth has demonstrated the utility of the TECRA ULTIMA SALMONELLA protocol. It is recommended that the minor modification to Method 998.09 be approved First Action as an additional option within the method.

  11. Development and Experimental Validation of a Dry Non-Invasive Multi-Channel Mouse Scalp EEG Sensor through Visual Evoked Potential Recordings

    Directory of Open Access Journals (Sweden)

    Donghyeon Kim

    2017-02-01

    Full Text Available In this paper, we introduce a dry non-invasive multi-channel sensor for measuring brainwaves on the scalps of mice. The research on laboratory animals provide insights to various practical applications involving human beings and other animals such as working animals, pets, and livestock. An experimental framework targeting the laboratory animals has the potential to lead to successful translational research when it closely resembles the environment of real applications. To serve scalp electroencephalography (EEG research environments for the laboratory mice, the dry non-invasive scalp EEG sensor with sixteen electrodes is proposed to measure brainwaves over the entire brain area without any surgical procedures. We validated the proposed sensor system with visual evoked potential (VEP experiments elicited by flash stimulations. The VEP responses obtained from experiments are compared with the existing literature, and analyzed in temporal and spatial perspectives. We further interpret the experimental results using time-frequency distribution (TFD and distance measurements. The developed sensor guarantees stable operations for in vivo experiments in a non-invasive manner without surgical procedures, therefore exhibiting a high potential to strengthen longitudinal experimental studies and reliable translational research exploiting non-invasive paradigms.

  12. Development and Experimental Validation of a Dry Non-Invasive Multi-Channel Mouse Scalp EEG Sensor through Visual Evoked Potential Recordings.

    Science.gov (United States)

    Kim, Donghyeon; Yeon, Chanmi; Kim, Kiseon

    2017-02-09

    In this paper, we introduce a dry non-invasive multi-channel sensor for measuring brainwaves on the scalps of mice. The research on laboratory animals provide insights to various practical applications involving human beings and other animals such as working animals, pets, and livestock. An experimental framework targeting the laboratory animals has the potential to lead to successful translational research when it closely resembles the environment of real applications. To serve scalp electroencephalography (EEG) research environments for the laboratory mice, the dry non-invasive scalp EEG sensor with sixteen electrodes is proposed to measure brainwaves over the entire brain area without any surgical procedures. We validated the proposed sensor system with visual evoked potential (VEP) experiments elicited by flash stimulations. The VEP responses obtained from experiments are compared with the existing literature, and analyzed in temporal and spatial perspectives. We further interpret the experimental results using time-frequency distribution (TFD) and distance measurements. The developed sensor guarantees stable operations for in vivo experiments in a non-invasive manner without surgical procedures, therefore exhibiting a high potential to strengthen longitudinal experimental studies and reliable translational research exploiting non-invasive paradigms.

  13. Reliability and validity of an agility-like incremental exercise test with multidirectional change-of-direction movements in response to a visual stimulus.

    Science.gov (United States)

    Born, Dennis-Peter; Kunz, Philipp; Sperlich, Billy

    2017-05-01

    The aim of the study was to evaluate the reliability and validity of cardiorespiratory and metabolic variables, that is, peak oxygen uptake (V'O2peak) and heart rate (HRpeak), obtained from an agility-like incremental exercise test for team sport athletes. To investigate the test-retest reliability, 25 team sport athletes (age: 22 ± 3 years, body mass: 75 ± 7 kg, height: 182 ± 6 cm) performed an agility-like incremental exercise test on the SpeedCourt (SC) system incorporating multidirectional change-of-direction (COD) movements twice. For each step of the incremental SC test, the athletes covered a 40-m distance interspersed with a 10-sec rest period. Each 40 m distance was split into short sprints (2.25-6.36 m) separated by multidirectional COD movements (0°-180°), which were performed in response to an external visual stimulus. All performance and physiological data were validated with variables obtained from a ramp-like treadmill and Yo-Yo intermittent recovery level 2 test (Yo-Yo IR2). The incremental SC test revealed high test-retest reliability for the time to exhaustion (ICC = 0.85, typical error [TE] = 0.44, and CV% = 3.88), V'O2peak, HRpeak, ventilation, and breathing frequency (ICC = 0.84, 0.72, 0.89, 0.77, respectively). The time to exhaustion (r = 0.50, 0.74) of the incremental SC test as well as the peak values for V'O2 (r = 0.59, 0.52), HR (r = 0.75, 0.78), ventilation (r = 0.57, 0.57), and breathing frequency (r = 0.68, 0.68) were significantly correlated (P ≤ 0.01) with the ramp-like treadmill test and the Yo-Yo IR2, respectively. The incremental SC test represents a reliable and valid method to assess peak values for V'O2 and HR with respect to the specific demand of team sport match play by incorporating multidirectional COD movements, decision making, and cognitive components. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the

  14. a Multi-Data Source and Multi-Sensor Approach for the 3d Reconstruction and Visualization of a Complex Archaelogical Site: the Case Study of Tolmo de Minateda

    Science.gov (United States)

    Torres-Martínez, J. A.; Seddaiu, M.; Rodríguez-Gonzálvez, P.; Hernández-López, D.; González-Aguilera, D.

    2015-02-01

    The complexity of archaeological sites hinders to get an integral modelling using the actual Geomatic techniques (i.e. aerial, closerange photogrammetry and terrestrial laser scanner) individually, so a multi-sensor approach is proposed as the best solution to provide a 3D reconstruction and visualization of these complex sites. Sensor registration represents a riveting milestone when automation is required and when aerial and terrestrial dataset must be integrated. To this end, several problems must be solved: coordinate system definition, geo-referencing, co-registration of point clouds, geometric and radiometric homogeneity, etc. Last but not least, safeguarding of tangible archaeological heritage and its associated intangible expressions entails a multi-source data approach in which heterogeneous material (historical documents, drawings, archaeological techniques, habit of living, etc.) should be collected and combined with the resulting hybrid 3D of "Tolmo de Minateda" located models. The proposed multi-data source and multi-sensor approach is applied to the study case of "Tolmo de Minateda" archaeological site. A total extension of 9 ha is reconstructed, with an adapted level of detail, by an ultralight aerial platform (paratrike), an unmanned aerial vehicle, a terrestrial laser scanner and terrestrial photogrammetry. In addition, the own defensive nature of the site (i.e. with the presence of three different defensive walls) together with the considerable stratification of the archaeological site (i.e. with different archaeological surfaces and constructive typologies) require that tangible and intangible archaeological heritage expressions can be integrated with the hybrid 3D models obtained, to analyse, understand and exploit the archaeological site by different experts and heritage stakeholders.

  15. Climate Reconstructions

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Paleoclimatology Program archives reconstructions of past climatic conditions derived from paleoclimate proxies, in addition to the Program's large holdings...

  16. Fusion and Visualization of HiRISE Super-Resolution, Shape-from-Shading DTM with MER Stereo 3D Reconstructions

    Science.gov (United States)

    Gupta, S.; Paar, G.; Muller, J. P.; Tao, Y.; Tyler, L.; Traxler, C.; Hesina, G.; Huber, B.; Nauschnegg, B.

    2014-12-01

    The FP7-SPACE project PRoViDE has assembled a major portion of the imaging data gathered so far from rover vehicles, landers and probes on extra-terrestrial planetary surfaces into a unique database, bringing them into a common planetary geospatial context and providing access to a complete set of 3D vision products. One major aim of PRoViDE is the fusion between orbiter and rover image products. To close the gap between HiRISE imaging resolution (down to 25cm for the OrthoRectified image (ORI), down to 1m for the DTM) and surface vision products, images from multiple HiRISE acquisitions are combined into a super resolution data set (Tao & Muller, 2014), increasing to 5cm resolution the Ortho images. Furthermore, shape-from-shading is applied to one of the ORIs at its original resolution for refinement of the HiRISE DTM, leading to DTM ground resolutions of up to 25 cm. After texture-based co-registration with these refined orbiter 3D products, MER PanCam and NavCam 3D image products can be smoothly pasted into a multi-resolution 3D data representation. Typical results from the MER mission are presented by a dedicated real-time rendering tool which is fed by a hierarchical 3D data structure that is able to cope with all involved scales from global planetary scale down to close-up reconstructions in the mm range. This allows us to explore and analyze the geological characteristics of rock outcrops, for example the detailed geometry and internal features of sedimentary rock layers, to aid paleoenvironmental interpretation. This integrated approach enables more efficient development of geological models of martian rock outcrops. The rendering tool also provides measurement tools to obtain geospatial data of surface points and distances between them. We report on novel scientific use cases and the added value potential of the resultant high-quality data set and presentation means to support further geologic investigations. The research leading to these results has

  17. Visual comparison for information visualization

    KAUST Repository

    Gleicher, M.

    2011-09-07

    Data analysis often involves the comparison of complex objects. With the ever increasing amounts and complexity of data, the demand for systems to help with these comparisons is also growing. Increasingly, information visualization tools support such comparisons explicitly, beyond simply allowing a viewer to examine each object individually. In this paper, we argue that the design of information visualizations of complex objects can, and should, be studied in general, that is independently of what those objects are. As a first step in developing this general understanding of comparison, we propose a general taxonomy of visual designs for comparison that groups designs into three basic categories, which can be combined. To clarify the taxonomy and validate its completeness, we provide a survey of work in information visualization related to comparison. Although we find a great diversity of systems and approaches, we see that all designs are assembled from the building blocks of juxtaposition, superposition and explicit encodings. This initial exploration shows the power of our model, and suggests future challenges in developing a general understanding of comparative visualization and facilitating the development of more comparative visualization tools. © The Author(s) 2011.

  18. Content validity of visual analog scales to assess symptom severity of acute angioedema attacks in adults with hereditary angioedema: an interview study.

    Science.gov (United States)

    McMillan, Carolyn Vivienne; Speight, Jane; Relan, Anurag; Bellizzi, Luca; Haase, Gerald; Cicardi, Marco

    2012-01-01

    Hereditary angioedema (HAE) is a rare, debilitating, potentially life-threatening condition characterized by recurrent acute attacks of edema of the skin, face/upper airway, and gastrointestinal and urogenital tracts. During a laryngeal attack, people with HAE may be at risk of suffocation, while other attacks are often associated with intense pain, disfigurement, disability, and/or vomiting. The intensity of some symptoms is known only to the person experiencing them. Thus, interview studies are needed to explore such experience and patient-reported outcome measures (PROMs) are required for systematic assessment of symptoms in the clinical setting and in clinical trials of treatments for acute HAE attacks. The aim of this interview study was to assess the content validity and suitability of four visual analog scale (VAS) instruments for use in clinical studies. The VAS instruments were designed to assess symptoms at abdominal, oro-facial-pharyngeal-laryngeal, peripheral, and urogenital attack locations. This is the first known study to report qualitative data about the patient's experience of the rare disorder, HAE. Semi-structured exploratory and cognitive debriefing interviews were conducted with 27 adults with a confirmed clinical/laboratory diagnosis of HAE (baseline plasma level of functional plasma protein C1 esterase inhibitor [C1INH] VAS-naïve. Experience of acute angioedema attacks was first explored, noting spontaneous mentions by participants of HAE symptomatology. Cognitive debriefing of the VAS instruments was undertaken to assess the suitability, comprehensibility, and relevance of the VAS items. Asymptomatic participants completed the VAS instruments relevant to their angioedema experience, reporting as if they were experiencing an acute angioedema attack at the time. Interviews were conducted in the clinic setting in the US and Italy over an 8-month period. Participants mentioned spontaneously almost all aspects of acute angioedema attacks covered

  19. Reliability and concurrent validity of visual analogue scale and modified verbal rating scale of pain assessment in adult patients with knee osteoathritis in Nigeria

    Directory of Open Access Journals (Sweden)

    M. O.B Olaogun

    2003-02-01

    Full Text Available The objective of this study was to determine the reliability and concurrent validity of two pain rating scales - Visual Analogue Scale (VAS and Verbal Rating Scale (VRS. The verbal rating scale was modified by translating the English description of subjective pain experience into vernacular (Yoruba equivalents and rating the knee pain when the patient was  standing with the knee  flexed . Twenty seven patients who were clinically and radiologically diagnosed with osteoarthritis (OA and with knee pain were purposively selected for the study. Two testers (physiotherapists independently rated the pain experienced by patients, when bearing full weight while standing on the affected leg with slight knee flexion, over a period of several days. For each patient pain was rated with the VAS and the modified VRS (MVRS. There were significant correlations between VAS and MVRS by the same tester (tester 1 and tester2 (r=0.92, p<0.01; r = 0.89,            p<0.01respectively, and between VAS and MVRS between tester 1 and tester 2 (r=0.91,p<0.01. There were no significant differences between VAS for tester 1 and VAS for tester 2, and between MVRS for tester 1and MVRS for tester 2 (p> 0.01.  According to this study, the two pain rating scales for knee OA are reliable. Our use of VAS and MVRS togetherwith the procedure involving the flexed knee posture is, therefore, recommended for wider clinical trials.

  20. Sparse matrix beamforming and image reconstruction for 2-D HIFU monitoring using harmonic motion imaging for focused ultrasound (HMIFU) with in vitro validation.

    Science.gov (United States)

    Hou, Gary Y; Provost, Jean; Grondin, Julien; Wang, Shutao; Marquet, Fabrice; Bunting, Ethan; Konofagou, Elisa E

    2014-11-01

    Harmonic motion imaging for focused ultrasound (HMIFU) utilizes an amplitude-modulated HIFU beam to induce a localized focal oscillatory motion simultaneously estimated. The objective of this study is to develop and show the feasibility of a novel fast beamforming algorithm for image reconstruction using GPU-based sparse-matrix operation with real-time feedback. In this study, the algorithm was implemented onto a fully integrated, clinically relevant HMIFU system. A single divergent transmit beam was used while fast beamforming was implemented using a GPU-based delay-and-sum method and a sparse-matrix operation. Axial HMI displacements were then estimated from the RF signals using a 1-D normalized cross-correlation method and streamed to a graphic user interface with frame rates up to 15 Hz, a 100-fold increase compared to conventional CPU-based processing. The real-time feedback rate does not require interrupting the HIFU treatment. Results in phantom experiments showed reproducible HMI images and monitoring of 22 in vitro HIFU treatments using the new 2-D system demonstrated reproducible displacement imaging, and monitoring of 22 in vitro HIFU treatments using the new 2-D system showed a consistent average focal displacement decrease of 46.7 ±14.6% during lesion formation. Complementary focal temperature monitoring also indicated an average rate of displacement increase and decrease with focal temperature at 0.84±1.15%/(°)C, and 2.03±0.93%/(°)C , respectively. These results reinforce the HMIFU capability of estimating and monitoring stiffness related changes in real time. Current ongoing studies include clinical translation of the presented system for monitoring of HIFU treatment for breast and pancreatic tumor applications.

  1. Visualization analysis and design

    CERN Document Server

    Munzner, Tamara

    2015-01-01

    Visualization Analysis and Design provides a systematic, comprehensive framework for thinking about visualization in terms of principles and design choices. The book features a unified approach encompassing information visualization techniques for abstract data, scientific visualization techniques for spatial data, and visual analytics techniques for interweaving data transformation and analysis with interactive visual exploration. It emphasizes the careful validation of effectiveness and the consideration of function before form. The book breaks down visualization design according to three questions: what data users need to see, why users need to carry out their tasks, and how the visual representations proposed can be constructed and manipulated. It walks readers through the use of space and color to visually encode data in a view, the trade-offs between changing a single view and using multiple linked views, and the ways to reduce the amount of data shown in each view. The book concludes with six case stu...

  2. Porcelain three-dimensional shape reconstruction and its color reconstruction

    Science.gov (United States)

    Yu, Xiaoyang; Wu, Haibin; Yang, Xue; Yu, Shuang; Wang, Beiyi; Chen, Deyun

    2013-01-01

    In this paper, structured light three-dimensional measurement technology was used to reconstruct the porcelain shape, and further more the porcelain color was reconstructed. So the accurate reconstruction of the shape and color of porcelain was realized. Our shape measurement installation drawing is given. Because the porcelain surface is color complex and highly reflective, the binary Gray code encoding is used to reduce the influence of the porcelain surface. The color camera was employed to obtain the color of the porcelain surface. Then, the comprehensive reconstruction of the shape and color was realized in Java3D runtime environment. In the reconstruction process, the space point by point coloration method is proposed and achieved. Our coloration method ensures the pixel corresponding accuracy in both of shape and color aspects. The porcelain surface shape and color reconstruction experimental results completed by proposed method and our installation, show that: the depth range is 860 ˜ 980mm, the relative error of the shape measurement is less than 0.1%, the reconstructed color of the porcelain surface is real, refined and subtle, and has the same visual effect as the measured surface.

  3. [Eyebrow reconstruction].

    Science.gov (United States)

    Baraër, F; Darsonval, V; Lejeune, F; Bochot-Hermouet, B; Rousseau, P

    2013-10-01

    The eyebrow is an essential anatomical area, from a social point of view, so its reconstruction, in case of skin defect, must be as meticulous as possible, with the less residual sequela. Capillary density extremely varies from one person to another and the different methods of restoration of this area should absolutely take this into consideration. We are going to review the various techniques of reconstruction, according to the sex and the surface to cover. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  4. Validation of 2 noninvasive, markerless reconstruction techniques in biplane high-speed fluoroscopy for 3-dimensional research of bovine distal limb kinematics.

    Science.gov (United States)

    Weiss, M; Reich, E; Grund, S; Mülling, C K W; Geiger, S M

    2017-10-01

    Lameness severely impairs cattle's locomotion, and it is among the most important threats to animal welfare, performance, and productivity in the modern dairy industry. However, insight into the pathological alterations of claw biomechanics leading to lameness and an understanding of the biomechanics behind development of claw lesions causing lameness are limited. Biplane high-speed fluoroscopic kinematography is a new approach for the analysis of skeletal motion. Biplane high-speed videos in combination with bone scans can be used for 3-dimensional (3D) animations of bones moving in 3D space. The gold standard, marker-based animation, requires implantation of radio-opaque markers into bones, which impairs the practicability for lameness research in live animals. Therefore, the purpose of this study was to evaluate the comparative accuracy of 2 noninvasive, markerless animation techniques (semi-automatic and manual) in 3D animation of the bovine distal limb. Tantalum markers were implanted into each of the distal, middle, and proximal phalanges of 5 isolated bovine distal forelimbs, and biplane high-speed x-ray videos of each limb were recorded to capture the simulation of one step. The limbs were scanned by computed tomography to create bone models of the 6 digital bones, and 3D animation of the bones' movements were subsequently reconstructed using the marker-based, the semi-automatic, and the manual animation techniques. Manual animation translational bias and precision varied from 0.63 ± 0.26 mm to 0.80 ± 0.49 mm, and rotational bias and precision ranged from 2.41 ± 1.43° to 6.75 ± 4.67°. Semi-automatic translational values for bias and precision ranged from 1.26 ± 1.28 mm to 2.75 ± 2.17 mm, and rotational values varied from 3.81 ± 2.78° to 11.7 ± 8.11°. In our study, we demonstrated the successful application of biplane high-speed fluoroscopic kinematography to gait analysis of bovine distal limb. Using the manual animation technique, kinematics

  5. Vaginal reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Lesavoy, M.A.

    1985-05-01

    Vaginal reconstruction can be an uncomplicated and straightforward procedure when attention to detail is maintained. The Abbe-McIndoe procedure of lining the neovaginal canal with split-thickness skin grafts has become standard. The use of the inflatable Heyer-Schulte vaginal stent provides comfort to the patient and ease to the surgeon in maintaining approximation of the skin graft. For large vaginal and perineal defects, myocutaneous flaps such as the gracilis island have been extremely useful for correction of radiation-damaged tissue of the perineum or for the reconstruction of large ablative defects. Minimal morbidity and scarring ensue because the donor site can be closed primarily. With all vaginal reconstruction, a compliant patient is a necessity. The patient must wear a vaginal obturator for a minimum of 3 to 6 months postoperatively and is encouraged to use intercourse as an excellent obturator. In general, vaginal reconstruction can be an extremely gratifying procedure for both the functional and emotional well-being of patients.

  6. Validation of a Manually Oscillating Chair for In-The-Field Assessment of Dynamic Visual Acuity on Crewmembers Within Hours of Returning From Long-Duration Spaceflight

    Science.gov (United States)

    Kreutzberg, G. A.; Rosenberg, M. J. F.; Peters, B. T.; Reschke,M. F.

    2017-01-01

    Long-duration spaceflight results in sensorimotor adaptations, which cause functional deficits during gravitational transitions, such as landing on a planetary surface after long-duration microgravity exposure. Both the vestibular system and the central nervous system are affected by gravitational transitions. These systems are responsible for coordinating head and eye movements via the vestibulo-ocular reflex (VOR) and go through an adaptation period upon exposure to microgravity. Consequently, they must also re-adapt to Earth's gravitational environment upon landing. This re-adaptation causes decrements in gaze control and dynamic visual acuity, with crewmembers reporting oscillopsia and blurred vision caused by retinal slip, or the inability to keep an image focused on their retina. This is thought to drive motion sickness symptoms experienced by most crewmembers following landing. Retinal slip can be estimated by dynamic visual acuity (DVA); visual acuity while in motion. Previously, DVA has been assessed in the laboratory where subjects walked at 6.4 km/hr on a motorized treadmill. Using this method, Peters et al. (2011) found that DVA is worsened in astronauts by an average of 0.75 eye-chart lines one day after landing. However, it is believed that re-adaptation occurs quickly and that DVA might be worse immediately upon re-exposure to a gravitational environment. Since many crewmembers are unable to walk safely upon landing, it was necessary to develop a method for replicating the vertical head movements associated with walking. In addition, the use of a chair to imitate the head displacement caused by walking isolates eye-head interactions without allowing for trunk and lower-body compensation, as seen with treadmill walking (Mulavara & Bloomberg 2003). Therefore, a modality for assessing DVA in the field within a few hours of landing was developed. In this study, we validated the ability of a manually operated oscillating chair to reproduce the oscillatory

  7. Advanced approach to the local structure reconstruction and theory validation on the example of the W L3-edge extended x-ray absorption fine structure of tungsten

    Science.gov (United States)

    Jonane, Inga; Anspoks, Andris; Kuzmin, Alexei

    2018-02-01

    Atomistic simulations of the experimental W L3-edge extended x-ray absorption fine structure (EXAFS) of bcc tungsten at T = 300 K were performed using classical molecular dynamics (MD) and reverse Monte Carlo (RMC) methods. The MD-EXAFS method based on the results of MD simulations allowed us to access the structural information, encoded in EXAFS, beyond the first coordination shell and to validate the accuracy of two interaction potential models—the embedded atom model potential and the second nearest-neighbor modified embedded atom method potential. The RMC-EXAFS method was used for more elaborate analysis of the EXAFS data giving access to thermal disorder effects. The results of both methods suggest that the correlation in atomic motion in bcc tungsten becomes negligible above 8 Å. This fact allowed us to use the EXAFS data to determine not only mean-square relative displacements of atomic W–W pair motion but also mean-square displacements of individual tungsten atoms, which are usually accessible from diffraction data only.

  8. Breast Reconstruction After Mastectomy

    Science.gov (United States)

    ... Cancers Breast Cancer Screening Research Breast Reconstruction After Mastectomy On This Page What is breast reconstruction? How ... are some new developments in breast reconstruction after mastectomy? What is breast reconstruction? Many women who have ...

  9. Breast reconstruction - implants

    Science.gov (United States)

    Breast implants surgery; Mastectomy - breast reconstruction with implants; Breast cancer - breast reconstruction with implants ... to make reconstruction easier. If you will have breast reconstruction later, your surgeon will remove enough skin ...

  10. Primary Vertex Reconstruction with the ATLAS Experiment

    CERN Document Server

    Casper, David William; The ATLAS collaboration

    2017-01-01

    ATLAS reconstructs primary vertices with high efficiency and resolution. These vertices serve as input to other mission critical analysis tools, and are relied on by many physics analyses. This presentation surveys the ATLAS primary vertex reconstruction algorithms, and describes validity checks done using real data. The complications introduced by pileup are discussed, along with refinements currently under study.

  11. Nonlinear reconstruction

    Science.gov (United States)

    Zhu, Hong-Ming; Yu, Yu; Pen, Ue-Li; Chen, Xuelei; Yu, Hao-Ran

    2017-12-01

    We present a direct approach to nonparametrically reconstruct the linear density field from an observed nonlinear map. We solve for the unique displacement potential consistent with the nonlinear density and positive definite coordinate transformation using a multigrid algorithm. We show that we recover the linear initial conditions up to the nonlinear scale (rδrδL>0.5 for k ≲1 h /Mpc ) with minimal computational cost. This reconstruction approach generalizes the linear displacement theory to fully nonlinear fields, potentially substantially expanding the baryon acoustic oscillations and redshift space distortions information content of dense large scale structure surveys, including for example SDSS main sample and 21 cm intensity mapping initiatives.

  12. Causal Reconstruction

    Science.gov (United States)

    1993-02-01

    suitable source of core events supporting causal reconstruction in a range of domains might be a combination of bodily - kinesthetic and simple...suggested in the previ- ous section, a good place to start might be with causal situations involving bodily - kinesthetic events or simple mechanical events...ANIZATION NAME(S) AND ADDRESS(LS) tý PJIfORMIN’, CRGANIZATION !.LPDRT NUMBEK Artificial Intelligence Laboratory 545 Technology Square AIM 1403 Cambridge

  13. Visual cognition

    National Research Council Canada - National Science Library

    Cavanagh, Patrick

    2011-01-01

    ... is unified in our mind even if not in the image. The construction of these entities is the task of visual cognition and, in almost all cases, each construct is a choice among an infinity of possibilities, chosen based on likelihood, bias, or a whim, but chosen by rejecting other valid competitors. The entities are not limited to static surfaces or structures but also include dynamic structures that only emerge over time – from dots that appear to be walking like a human or a moon orbiting a planet, to the...

  14. Fused analytical and iterative reconstruction (AIR) via modified proximal forward-backward splitting: a FDK-based iterative image reconstruction example for CBCT.

    Science.gov (United States)

    Gao, Hao

    2016-10-07

    This work is to develop a general framework, namely analytical iterative reconstruction (AIR) method, to incorporate analytical reconstruction (AR) method into iterative reconstruction (IR) method, for enhanced CT image quality and reconstruction efficiency. Specifically, AIR is established based on the modified proximal forward-backward splitting (PFBS) algorithm, and its connection to the filtered data fidelity with sparsity regularization is discussed. As a result, AIR decouples data fidelity and image regularization with a two-step iterative scheme, during which an AR-projection step updates the filtered data fidelity term, while a denoising solver updates the sparsity regularization term. During the AR-projection step, the image is projected to the data domain to form the data residual, and then reconstructed by certain AR to a residual image which is then weighted together with previous image iterate to form next image iterate. Intuitively since the eigenvalues of AR-projection operator are close to the unity, PFBS based AIR has a fast convergence. Such an advantage is rigorously established through convergence analysis and numerical computation of convergence rate. The proposed AIR method is validated in the setting of circular cone-beam CT with AR being FDK and total-variation sparsity regularization, and has improved image quality from both AR and IR. For example, AIR has improved visual assessment and quantitative measurement in terms of both contrast and resolution, and reduced axial and half-fan artifacts.

  15. Fused analytical and iterative reconstruction (AIR) via modified proximal forward-backward splitting: a FDK-based iterative image reconstruction example for CBCT

    Science.gov (United States)

    Gao, Hao

    2016-10-01

    This work is to develop a general framework, namely analytical iterative reconstruction (AIR) method, to incorporate analytical reconstruction (AR) method into iterative reconstruction (IR) method, for enhanced CT image quality and reconstruction efficiency. Specifically, AIR is established based on the modified proximal forward-backward splitting (PFBS) algorithm, and its connection to the filtered data fidelity with sparsity regularization is discussed. As a result, AIR decouples data fidelity and image regularization with a two-step iterative scheme, during which an AR-projection step updates the filtered data fidelity term, while a denoising solver updates the sparsity regularization term. During the AR-projection step, the image is projected to the data domain to form the data residual, and then reconstructed by certain AR to a residual image which is then weighted together with previous image iterate to form next image iterate. Intuitively since the eigenvalues of AR-projection operator are close to the unity, PFBS based AIR has a fast convergence. Such an advantage is rigorously established through convergence analysis and numerical computation of convergence rate. The proposed AIR method is validated in the setting of circular cone-beam CT with AR being FDK and total-variation sparsity regularization, and has improved image quality from both AR and IR. For example, AIR has improved visual assessment and quantitative measurement in terms of both contrast and resolution, and reduced axial and half-fan artifacts.

  16. Validity of Measures Reflecting Visual Discrimination and Linguistic Constructs for a Sample of Second-Grade Hispanic Children Receiving Reading Instruction in Spanish.

    Science.gov (United States)

    Morrison, James A.; Michael, William B.

    1984-01-01

    The concurrent and discriminant validity of La Prueba de Analisis Auditivo, a Spanish auditory perception test, and the validity of the perceptual deficit hypothesis and of hypotheses derived from verbal processing theory were evaluated in a sample of 114 second-grade Hispanic pupils receiving reading instruction in Spanish. (Author/BW)

  17. Accuracy and Validity of Goniometer and Visual Assessments of Angular Joint Positions of the Hand and Wrist.

    Science.gov (United States)

    McVeigh, Kimberly H; Murray, Peter M; Heckman, Michael G; Rawal, Bhupendra; Peterson, Jeffrey J

    2016-04-01

    To compare goniometric and visual assessments of angular hand joint and wrist joint positions measured by board-certified hand surgeons and certified hand therapists. We hypothesized that visual estimation would be similar to the goniometric measurement accuracy of digital and wrist joint positions. The wrist, index finger metacarpophalangeal (MCP) joint, and index finger proximal interphalangeal (PIP) joint were evaluated in different positions by 40 observers: 20 board-certified hand surgeons and 20 certified hand therapists. Each observer estimated the position of the wrist, index MCP joint, and index PIP joint of the same volunteer, who was positioned in low-profile orthoses to reproduce predetermined positions. Following visual estimation, the participants measured the same joint positions using a goniometer. The control measurement was digitally determined by a radiologist who obtained radiographs of the hand and wrist positions in each orthosis. Observers were blinded to the results of control measurements. When considering all joints at all positions, neither visual assessments nor goniometer assessments were consistently within ± 5° of the measurements obtained on control radiographs. When considering individual joints, goniometer measurements were significantly closer to control radiograph measurements than the visual assessments for all 3 PIP joint positions. There was no difference for the measurements at the wrist or for 2 of the 3 MCP joint positions. Significant differences between surgeon and therapist joint angle measurements were not observed when comparing visual and goniometer assessments to radiograph controls. Compared with radiograph measurements, neither visual nor goniometer assessment displayed high levels of accuracy. On average, visual assessment of the angular positions of the index MCP and wrist joint were as accurate as the goniometer assessment, whereas goniometer assessment of the angular position of the PIP joint was more

  18. Declarative Visualization Queries

    Science.gov (United States)

    Pinheiro da Silva, P.; Del Rio, N.; Leptoukh, G. G.

    2011-12-01

    necessarily entirely exposed to scientists writing visualization queries, facilitates the automated construction of visualization pipelines. VisKo queries have been successfully used in support of visualization scenarios from Earth Science domains including: velocity model isosurfaces, gravity data raster, and contour map renderings. Our synergistic environment provided by our CYBER-ShARE initiative at the University of Texas at El Paso has allowed us to work closely with Earth Science experts that have both provided us our test data as well as validation as to whether the execution of VisKo queries are returning visualizations that can be used for data analysis. Additionally, we have employed VisKo queries to support visualization scenarios associated with Giovanni, an online platform for data analysis developed by NASA GES DISC. VisKo-enhanced visualizations included time series plotting of aerosol data as well as contour and raster map generation of gridded brightness-temperature data.

  19. Proximal Gastrojejunal Reconstruction after Pancreaticoduodenal Resection

    Directory of Open Access Journals (Sweden)

    M. Wayne

    2012-01-01

    Full Text Available Introduction. Reconstruction by proximal gastrojejunostomy, and distal biliary and pancreatic anastomoses is infrequently used after resection of the head of the pancreas because of fear of fistulas and cholangitis. Pancreaticoduodenectomy is being performed more frequently for cystic malignant and premalignant lesions. Because of this there is a need for endoscopic visualization and biopsy of the residual pancreatic duct, since multi-centricity is characteristic of some of these malignancies. Since endoscopic access of the bile duct and pancreatic duct is difficult and unsuccessful in 50–70% after B II or Roux Y reconstruction, we prospectively studied the merit and complications (early and late of proximal gastrojejunal (PGJ reconstruction after pancreaticoduodenal resection. Material and Methods. Thirty nine consecutive, non-radomized patients underwent pancreaticoduodenectomy and PGJ reconstruction over 14 mos. There were 21 males and 18 females. Results. 7 patients with IPMN have undergone repeat CT scanning for surveillance, with 3 requiring repeat EUS and ERCP. There were no technical difficulties accessing the pancreas or the pancreatic duct, supporting the PGJ reconstruction. Conclusion. Proximal gastrojejunal reconstruction following pancreaticoduodenal resection may be safely done with similar morbidity to traditional pancreaticojejunal reconstructions. PGJ reconstruction may be of greater value when direct visual access to the bile duct or pancreatic duct is necessary, and should be considered when doing resection for mucinous cysts or IPMN of the head of the pancreas.

  20. A noise-optimized virtual monochromatic reconstruction algorithm improves stent visualization and diagnostic accuracy for detection of in-stent re-stenosis in lower extremity run-off CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Mangold, Stefanie [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); De Cecco, Carlo N.; Yamada, Ricardo T.; Varga-Szemes, Akos; Stubenrauch, Andrew C.; Fuller, Stephen R. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Schoepf, U.J. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Caruso, Damiano [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' , Department of Radiological Sciences, Oncology and Pathology, Rome (Italy); Vogl, Thomas J.; Wichmann, Julian L. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Nikolaou, Konstantin [Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Todoran, Thomas M. [Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States)

    2016-12-15

    To evaluate the impact of noise-optimized virtual monochromatic imaging (VMI+) on stent visualization and accuracy for in-stent re-stenosis at lower extremity dual-energy CT angiography (DE-CTA). We evaluated third-generation dual-source DE-CTA studies in 31 patients with prior stent placement. Images were reconstructed with linear blending (F{sub 0}.5) and VMI+ at 40-150 keV. In-stent luminal diameter was measured and contrast-to-noise ratio (CNR) calculated. Diagnostic confidence was determined using a five-point scale. In 21 patients with invasive catheter angiography, accuracy for significant re-stenosis (≥50 %) was assessed at F{sub 0}.5 and 80 keV-VMI+ chosen as the optimal energy level based on image-quality analysis. At CTA, 45 stents were present. DSA was available for 28 stents whereas 12 stents showed significant re-stenosis. CNR was significantly higher with ≤80 keV-VMI+ (17.9 ± 6.4-33.7 ± 12.3) compared to F{sub 0}.5 (16.9 ± 4.8; all p < 0.0463); luminal stent diameters were increased at ≥70 keV (5.41 ± 1.8-5.92 ± 1.7 vs. 5.27 ± 1.8, all p < 0.001) and diagnostic confidence was highest at 70-80 keV-VMI+ (4.90 ± 0.48-4.88 ± 0.63 vs. 4.60 ± 0.66, p = 0.001, 0.0042). Sensitivity, negative predictive value and accuracy for re-stenosis were higher with 80 keV-VMI+ (100, 100, 96.4 %) than F{sub 0}.5 (90.9, 94.1, 89.3 %). 80 keV-VMI+ improves image quality, diagnostic confidence and accuracy for stent evaluation at lower extremity DE-CTA. (orig.)

  1. Use of the orbicularis retaining ligament in lower eyelid reconstruction.

    Science.gov (United States)

    Skillman, J; Hardy, T; Kirkpatrick, N; Joshi, N; Kelly, M

    2009-07-01

    The orbicularis retaining ligament (ORL) is a distinct anatomical structure that has only been recently characterised. A variety of techniques, based on Hamra's concepts, now divide this ligament during lower lid blepharoplasty. This often produces a substantial skin excess which is discarded. We set out to investigate the validity of this surgical manoeuvre as a means of recruiting anterior lamella for the purposes of lower lid reconstruction. Between September 2002 and August 2004, 23 patients underwent reconstruction of the anterior lamella of their lower eyelid using this technique. The mean age of the patients was 56 years (range 26-86 years). The mean follow-up time was 20 months (range 12-36 months). Clinical evaluation was carried out preoperatively and postoperatively to assess the presence of palpebral non occlusion, epiphora, the sensation of a dry eye, ectropion, conjunctivitis and keratitis. Assessment of the tissue deficit was made clinically and with standardised digital photographs. Satisfactory reconstruction of the anterior lamella of the lower eyelid was achieved in 19/23 patients. Preoperative symptoms of epiphora and lower lid position were improved. The visual analogue scale of appearance was improved postoperatively. In some cases, particularly in the atrophic lower lid, the results were short lived and further surgery was required to achieve optimal results. In cases of isolated cutaneous deficit where the lid support mechanisms are intact, the procedure is both successful and aesthetically favourable for resurfacing this challenging area.

  2. Visual Impairment

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Visual Impairment KidsHealth / For Teens / Visual Impairment What's in ... with the brain, making vision impossible. What Is Visual Impairment? Many people have some type of visual ...

  3. Visual field

    Science.gov (United States)

    Perimetry; Tangent screen exam; Automated perimetry exam; Goldmann visual field exam; Humphrey visual field exam ... Confrontation visual field exam. This is a quick and basic check of the visual field. The health care provider ...

  4. Comparison of visual scoring and quantitative planimetry methods for estimation of global infarct size on delayed enhanced cardiac MRI and validation with myocardial enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Mewton, Nathan, E-mail: nmewton@gmail.com [Hopital Cardiovasculaire Louis Pradel, 28, Avenue Doyen Lepine, 69677 Bron cedex, Hospices Civils de Lyon (France); CREATIS-LRMN (Centre de Recherche et d' Applications en Traitement de l' Image et du Signal), Universite Claude Bernard Lyon 1, UMR CNRS 5220, U 630 INSERM (France); Revel, Didier [Hopital Cardiovasculaire Louis Pradel, 28, Avenue Doyen Lepine, 69677 Bron cedex, Hospices Civils de Lyon (France); CREATIS-LRMN (Centre de Recherche et d' Applications en Traitement de l' Image et du Signal), Universite Claude Bernard Lyon 1, UMR CNRS 5220, U 630 INSERM (France); Bonnefoy, Eric [Hopital Cardiovasculaire Louis Pradel, 28, Avenue Doyen Lepine, 69677 Bron cedex, Hospices Civils de Lyon (France); Ovize, Michel [Hopital Cardiovasculaire Louis Pradel, 28, Avenue Doyen Lepine, 69677 Bron cedex, Hospices Civils de Lyon (France); INSERM Unite 886 (France); Croisille, Pierre [Hopital Cardiovasculaire Louis Pradel, 28, Avenue Doyen Lepine, 69677 Bron cedex, Hospices Civils de Lyon (France); CREATIS-LRMN (Centre de Recherche et d' Applications en Traitement de l' Image et du Signal), Universite Claude Bernard Lyon 1, UMR CNRS 5220, U 630 INSERM (France)

    2011-04-15

    Purpose: Although delayed enhanced CMR has become a reference method for infarct size quantification, there is no ideal method to quantify total infarct size in a routine clinical practice. In a prospective study we compared the performance and post-processing time of a global visual scoring method to standard quantitative planimetry and we compared both methods to the peak values of myocardial biomarkers. Materials and methods: This study had local ethics committee approval; all patients gave written informed consent. One hundred and three patients admitted with reperfused AMI to our intensive care unit had a complete CMR study with gadolinium-contrast injection 4 {+-} 2 days after admission. A global visual score was defined on a 17-segment model and compared with the quantitative planimetric evaluation of hyperenhancement. The peak values of serum Troponin I (TnI) and creatine kinase (CK) release were measured in each patient. Results: The mean percentage of total left ventricular myocardium with hyperenhancement determined by the quantitative planimetry method was (20.1 {+-} 14.6) with a range of 1-68%. There was an excellent correlation between quantitative planimetry and visual global scoring for the hyperenhancement extent's measurement (r = 0.94; y = 1.093x + 0.87; SEE = 1.2; P < 0.001) The Bland-Altman plot showed a good concordance between the two approaches (mean of the differences = 1.9% with a standard deviation of 4.7). Mean post-processing time for quantitative planimetry was significantly longer than visual scoring post-processing time (23.7 {+-} 5.7 min vs 5.0 {+-} 1.1 min respectively, P < 0.001). Correlation between peak CK and quantitative planimetry was r = 0.82 (P < 0.001) and r = 0.83 (P < 0.001) with visual global scoring. Correlation between peak Troponin I and quantitative planimetry was r = 0.86 (P < 0.001) and r = 0.85 (P < 0.001) with visual global scoring. Conclusion: A visual approach based on a 17-segment model allows a rapid

  5. Local Surface Reconstruction from MER images using Stereo Workstation

    Science.gov (United States)

    Shin, Dongjoe; Muller, Jan-Peter

    2010-05-01

    The authors present a semi-automatic workflow that reconstructs the 3D shape of the martian surface from local stereo images delivered by PnCam or NavCam on systems such as the NASA Mars Exploration Rover (MER) Mission and in the future the ESA-NASA ExoMars rover PanCam. The process is initiated with manually selected tiepoints on a stereo workstation which is then followed by a tiepoint refinement, stereo-matching using region growing and Levenberg-Marquardt Algorithm (LMA)-based bundle adjustment processing. The stereo workstation, which is being developed by UCL in collaboration with colleagues at the Jet Propulsion Laboratory (JPL) within the EU FP7 ProVisG project, includes a set of practical GUI-based tools that enable an operator to define a visually correct tiepoint via a stereo display. To achieve platform and graphic hardware independence, the stereo application has been implemented using JPL's JADIS graphic library which is written in JAVA and the remaining processing blocks used in the reconstruction workflow have also been developed as a JAVA package to increase the code re-usability, portability and compatibility. Although initial tiepoints from the stereo workstation are reasonably acceptable as true correspondences, it is often required to employ an optional validity check and/or quality enhancing process. To meet this requirement, the workflow has been designed to include a tiepoint refinement process based on the Adaptive Least Square Correlation (ALSC) matching algorithm so that the initial tiepoints can be further enhanced to sub-pixel precision or rejected if they fail to pass the ALSC matching threshold. Apart from the accuracy of reconstruction, it is obvious that the other criterion to assess the quality of reconstruction is the density (or completeness) of reconstruction, which is not attained in the refinement process. Thus, we re-implemented a stereo region growing process, which is a core matching algorithm within the UCL

  6. Visualization of Tooth for Non-Destructive Evaluation from CT Images

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Hui; Chae, Ok Sam [Kyung Hee University, Seoul (Korea, Republic of)

    2009-06-15

    This paper reports an effort to develop 3D tooth visualization system from CT sequence images as a part of the non-destructive evaluation suitable for the simulation of endodontics, orthodontics and other dental treatments. We focus on the segmentation and visualization for the individual tooth. In dental CT images teeth are touching the adjacent teeth or surrounded by the alveolar bones with similar intensity. We propose an improved level set method with shape prior to separate a tooth from other teeth as well as the alveolar bones. Reconstructed 3D model of individual tooth based on the segmentation results indicates that our technique is a very conducive tool for tooth visualization, evaluation and diagnosis. Some comparative visualization results validate the non-destructive function of our method.

  7. Reconstructing Normality

    DEFF Research Database (Denmark)

    Gildberg, Frederik Alkier; Bradley, Stephen K.; Fristed, Peter Billeskov

    2012-01-01

    Forensic psychiatry is an area of priority for the Danish Government. As the field expands, this calls for increased knowledge about mental health nursing practice, as this is part of the forensic psychiatry treatment offered. However, only sparse research exists in this area. The aim of this study...... was to investigate the characteristics of forensic mental health nursing staff interaction with forensic mental health inpatients and to explore how staff give meaning to these interactions. The project included 32 forensic mental health staff members, with over 307 hours of participant observations, 48 informal...... interviews, and seven semistructured interviews. The findings show that staff interaction is typified by the use of trust and relationship-enabling care, which is characterized by the establishment and maintenance of an informal, trusting relationship through a repeated reconstruction of normality...

  8. Three-way ROC validation of rs-fMRI visual information propagation transfer functions used to differentiate between RRMS and CIS optic neuritis patients.

    Science.gov (United States)

    Farahani, Ehsan Shahrabi; Choudhury, Samiul H; Cortese, Filomeno; Costello, Fiona; Goodyear, Bradley; Smith, Michael R

    2017-07-01

    Resting-state fMRI (rs-fMRI) measures the temporal synchrony between different brain regions while the subject is at rest. We present an investigation using visual information propagation transfer functions as potential optic neuritis (ON) markers for the pathways between the lateral geniculate nuclei, the primary visual cortex, the lateral occipital cortex and the superior parietal cortex. We investigate marker reliability in differentiating between healthy controls and ON patients with clinically isolated syndrome (CIS), and relapsing-remitting multiple sclerosis (RRMS) using a three-way receiver operating characteristics analysis. We identify useful and reliable three-way ON related metrics in the rs-fMRI low-frequency band 0.0 Hz to 0.1 Hz, with potential markers associated with the higher frequency harmonics of these signals in the 0.1 Hz to 0.2 Hz and 0.2 Hz to 0.3 Hz bands.

  9. Reconstructing the Alcatraz escape

    Science.gov (United States)

    Baart, F.; Hoes, O.; Hut, R.; Donchyts, G.; van Leeuwen, E.

    2014-12-01

    In the night of June 12, 1962 three inmates used a raft made of raincoatsto escaped the ultimate maximum security prison island Alcatraz in SanFrancisco, United States. History is unclear about what happened tothe escapees. At what time did they step into the water, did theysurvive, if so, where did they reach land? The fate of the escapees has been the subject of much debate: did theymake landfall on Angel Island, or did the current sweep them out ofthe bay and into the cold pacific ocean? In this presentation, we try to shed light on this historic case using avisualization of a high-resolution hydrodynamic simulation of the San Francisco Bay, combined with historical tidal records. By reconstructing the hydrodynamic conditions and using a particle based simulation of the escapees we show possible scenarios. The interactive model is visualized using both a 3D photorealistic and web based visualization. The "Escape from Alcatraz" scenario demonstrates the capabilities of the 3Di platform. This platform is normally used for overland flooding (1D/2D). The model engine uses a quad tree structure, resulting in an order of magnitude speedup. The subgrid approach takes detailed bathymetry information into account. The inter-model variability is tested by comparing the results with the DFlow Flexible Mesh (DFlowFM) San Francisco Bay model. Interactivity is implemented by converting the models from static programs to interactive libraries, adhering to the Basic ModelInterface (BMI). Interactive models are more suitable for answeringexploratory research questions such as this reconstruction effort. Although these hydrodynamic simulations only provide circumstantialevidence for solving the mystery of what happened during the foggy darknight of June 12, 1962, it can be used as a guidance and provides aninteresting testcase to apply interactive modelling.

  10. Applications of Lexical Link Analysis Web Service for Large-Scale Automation, Validation, Discovery, Visualization, and Real-Time Program-Awareness

    Science.gov (United States)

    2012-04-30

    closeness of the systems in comparison can be visually examined or examined using the Quadratic Assignment Procedure ( QAP ; Hubert & Schultz, 1976, e.g...Comparing Two Time Periods Figure 16. QAP Correlation via UCINET Each node, or word hub, represents a system feature, and each color refers to the...Systems Experimentation, Naval Postgraduate School BACK-UP SLIDES Statistical Test Example: QAP Correlation Quadratic Assignment Procedure [ QAP

  11. Is a single-item visual analogue scale as valid, reliable and responsive as multi-item scales in measuring quality of life?

    NARCIS (Netherlands)

    Boer, A.G.E.M. de; Lanschot, J.J.B. van; Stalmeier, P.F.M.; Sandick, J.W. van; Hulscher, J.B.F.; Haes, J.C.J.M. de; Sprangers, M.A.G.

    2004-01-01

    PURPOSE: To compare the validity, reliability and responsiveness of a single, global quality of life question to multi-item scales. METHOD: Data were obtained from 83 consecutive patients with oesophageal adenocarcinoma undergoing either transhiatal or transthoracic oesophagectomy. Quality of life

  12. Reconstructive Urology

    Directory of Open Access Journals (Sweden)

    Fikret Fatih Önol

    2014-11-01

    Full Text Available In the treatment of urethral stricture, Buccal Mucosa Graft (BMG and reconstruction is applied with different patch techniques. Recently often prefered, this approach is, in bulber urethra strictures of BMG’s; by “ventral onley”, in pendulous urethra because of thinner spingiosis body, which provides support and nutrition of graft; by means of “dorsal inley” being anastomosis. In the research that Cordon et al. did, they compared conventional BMJ “onley” urethroplast and “pseudo-spongioplasty” which base on periurethral vascular tissues to be nourished by closing onto graft. In repairment of front urethras that spongiosis supportive tissue is insufficient, this method is defined as peripheral dartos [çevre dartos?] and buck’s fascia being mobilized and being combined on BMG patch. Between the years 2007 and 2012, assessment of 56 patients with conventional “ventral onley” BMG urethroplast and 46 patients with “pseudo-spongioplasty” were reported to have similar success rates (80% to 84% in 3.5 year follow-up on average. While 74% of the patients that were applied pseudo-spongioplasty had disease present at distal urethra (pendulous, bulbopendulous, 82% of the patients which were applied conventional onley urethroplast had stricture at proximal (bulber urethra yet. Also lenght of the stricture at the pseudo-spongioplasty group was longer in a statistically significant way (5.8 cm to 4.7 cm on average, p=0.028. This study which Cordon et al. did, shows that conditions in which conventional sponjiyoplasti is not possible, periurethral vascular tissues are adequate to nourish BMG. Even it is an important technique in terms of bringing a new point of view to today’s practice, data especially about complications that may show up after pseudo-spongioplasty usage on long distal strictures (e.g. appearance of urethral diverticulum is not reported. Along with this we think that, providing an oppurtinity to patch directly

  13. Live ultrasound volume reconstruction using scout scanning.

    Science.gov (United States)

    Meyer, Amelie; Lasso, Andras; Ungi, Tamas; Fichtinger, Gabor

    2015-02-21

    Ultrasound-guided interventions often necessitate scanning of deep-seated anatomical structures that may be hard to visualize. Visualization can be improved using reconstructed 3D ultrasound volumes. High-resolution 3D reconstruction of a large area during clinical interventions is challenging if the region of interest is unknown. We propose a two-stage scanning method allowing the user to perform quick low-resolution scouting followed by high-resolution live volume reconstruction. Scout scanning is accomplished by stacking 2D tracked ultrasound images into a low-resolution volume. Then, within a region of interest defined in the scout scan, live volume reconstruction can be performed by continuous scanning until sufficient image density is achieved. We implemented the workflow as a module of the open-source 3D Slicer application, within the SlicerIGT extension and building on the PLUS toolkit. Scout scanning is performed in a few seconds using 3 mm spacing to allow region of interest definition. Live reconstruction parameters are set to provide good image quality (0.5 mm spacing, hole filling enabled) and feedback is given during live scanning by regularly updated display of the reconstructed volume. Use of scout scanning may allow the physician to identify anatomical structures. Subsequent live volume reconstruction in a region of interest may assist in procedures such as targeting needle interventions or estimating brain shift during surgery.

  14. 3D reconstruction and analysis of wing deformation in free-flying dragonflies.

    Science.gov (United States)

    Koehler, Christopher; Liang, Zongxian; Gaston, Zachary; Wan, Hui; Dong, Haibo

    2012-09-01

    Insect wings demonstrate elaborate three-dimensional deformations and kinematics. These deformations are key to understanding many aspects of insect flight including aerodynamics, structural dynamics and control. In this paper, we propose a template-based subdivision surface reconstruction method that is capable of reconstructing the wing deformations and kinematics of free-flying insects based on the output of a high-speed camera system. The reconstruction method makes no rigid wing assumptions and allows for an arbitrary arrangement of marker points on the interior and edges of each wing. The resulting wing surfaces are projected back into image space and compared with expert segmentations to validate reconstruction accuracy. A least squares plane is then proposed as a universal reference to aid in making repeatable measurements of the reconstructed wing deformations. Using an Eastern pondhawk (Erythimus simplicicollis) dragonfly for demonstration, we quantify and visualize the wing twist and camber in both the chord-wise and span-wise directions, and discuss the implications of the results. In particular, a detailed analysis of the subtle deformation in the dragonfly's right hindwing suggests that the muscles near the wing root could be used to induce chord-wise camber in the portion of the wing nearest the specimen's body. We conclude by proposing a novel technique for modeling wing corrugation in the reconstructed flapping wings. In this method, displacement mapping is used to combine wing surface details measured from static wings with the reconstructed flapping wings, while not requiring any additional information be tracked in the high speed camera output.

  15. Robust Building Facade Reconstruction from Spaceborne TOMOSAR Points

    Science.gov (United States)

    Shahzad, M.; Zhu, X. X.

    2013-10-01

    With improved sensor resolution and advanced multi-pass interferometric techniques such as SAR tomographic inversion (TomoSAR), it is now possible to reconstruct both shape and motion of urban infrastructures. These sophisticated techniques not only opens up new possibilities to monitor and visualize the dynamics of urban infrastructure in very high level of details but also allows us to take a step further towards generation of 4D (space-time) or even higher dimensional dynamic city models that can potentially incorporate temporal (motion) behaviour along with the 3D information. Motivated by these chances, this paper presents a post processing approach that systematically allows automatic reconstruction of building façades from 4D point cloud generated from tomographic SAR processing and put the particular focus on robust reconstruction of large areas. The approach is modular and consists of extracting facade points via point density estimation procedure based on directional window approach. Segmentation of facades into individual segments is then carried out using an unsupervised clustering procedure combining both the density-based clustering and the mean-shift algorithm. Subsequently, points of individual facade segments are identified as belonging to flat or curved surface and general 1st and 2nd order polynomials are used to model the facade geometry. Finally, intersection points of the adjacent façades describing the vertex points are determined to complete the reconstruction process. The proposed approach is illustrated and validated by examples using TomoSAR point clouds over the city of Las Vegas generated from a stack of TerraSARX high resolution spotlight images.

  16. Creativity, visualization abilities, and visual cognitive style.

    Science.gov (United States)

    Kozhevnikov, Maria; Kozhevnikov, Michael; Yu, Chen Jiao; Blazhenkova, Olesya

    2013-06-01

    Despite the recent evidence for a multi-component nature of both visual imagery and creativity, there have been no systematic studies on how the different dimensions of creativity and imagery might interrelate. The main goal of this study was to investigate the relationship between different dimensions of creativity (artistic and scientific) and dimensions of visualization abilities and styles (object and spatial). In addition, we compared the contributions of object and spatial visualization abilities versus corresponding styles to scientific and artistic dimensions of creativity. Twenty-four undergraduate students (12 females) were recruited for the first study, and 75 additional participants (36 females) were recruited for an additional experiment. Participants were administered a number of object and spatial visualization abilities and style assessments as well as a number of artistic and scientific creativity tests. The results show that object visualization relates to artistic creativity and spatial visualization relates to scientific creativity, while both are distinct from verbal creativity. Furthermore, our findings demonstrate that style predicts corresponding dimension of creativity even after removing shared variance between style and visualization ability. The results suggest that styles might be a more ecologically valid construct in predicting real-life creative behaviour, such as performance in different professional domains. © 2013 The British Psychological Society.

  17. A technique system for the measurement, reconstruction and character extraction of rice plant architecture

    Science.gov (United States)

    Li, Xumeng; Wang, Xiaohui; Wei, Hailin; Zhu, Xinguang; Peng, Yulin; Li, Ming; Li, Tao; Huang, Huang

    2017-01-01

    This study developed a technique system for the measurement, reconstruction, and trait extraction of rice canopy architectures, which have challenged functional–structural plant modeling for decades and have become the foundation of the design of ideo-plant architectures. The system uses the location-separation-measurement method (LSMM) for the collection of data on the canopy architecture and the analytic geometry method for the reconstruction and visualization of the three-dimensional (3D) digital architecture of the rice plant. It also uses the virtual clipping method for extracting the key traits of the canopy architecture such as the leaf area, inclination, and azimuth distribution in spatial coordinates. To establish the technique system, we developed (i) simple tools to measure the spatial position of the stem axis and azimuth of the leaf midrib and to capture images of tillers and leaves; (ii) computer software programs for extracting data on stem diameter, leaf nodes, and leaf midrib curves from the tiller images and data on leaf length, width, and shape from the leaf images; (iii) a database of digital architectures that stores the measured data and facilitates the reconstruction of the 3D visual architecture and the extraction of architectural traits; and (iv) computation algorithms for virtual clipping to stratify the rice canopy, to extend the stratified surface from the horizontal plane to a general curved surface (including a cylindrical surface), and to implement in silico. Each component of the technique system was quantitatively validated and visually compared to images, and the sensitivity of the virtual clipping algorithms was analyzed. This technique is inexpensive and accurate and provides high throughput for the measurement, reconstruction, and trait extraction of rice canopy architectures. The technique provides a more practical method of data collection to serve functional–structural plant models of rice and for the optimization of rice

  18. A technique system for the measurement, reconstruction and character extraction of rice plant architecture.

    Science.gov (United States)

    Li, Xumeng; Wang, Xiaohui; Wei, Hailin; Zhu, Xinguang; Peng, Yulin; Li, Ming; Li, Tao; Huang, Huang

    2017-01-01

    This study developed a technique system for the measurement, reconstruction, and trait extraction of rice canopy architectures, which have challenged functional-structural plant modeling for decades and have become the foundation of the design of ideo-plant architectures. The system uses the location-separation-measurement method (LSMM) for the collection of data on the canopy architecture and the analytic geometry method for the reconstruction and visualization of the three-dimensional (3D) digital architecture of the rice plant. It also uses the virtual clipping method for extracting the key traits of the canopy architecture such as the leaf area, inclination, and azimuth distribution in spatial coordinates. To establish the technique system, we developed (i) simple tools to measure the spatial position of the stem axis and azimuth of the leaf midrib and to capture images of tillers and leaves; (ii) computer software programs for extracting data on stem diameter, leaf nodes, and leaf midrib curves from the tiller images and data on leaf length, width, and shape from the leaf images; (iii) a database of digital architectures that stores the measured data and facilitates the reconstruction of the 3D visual architecture and the extraction of architectural traits; and (iv) computation algorithms for virtual clipping to stratify the rice canopy, to extend the stratified surface from the horizontal plane to a general curved surface (including a cylindrical surface), and to implement in silico. Each component of the technique system was quantitatively validated and visually compared to images, and the sensitivity of the virtual clipping algorithms was analyzed. This technique is inexpensive and accurate and provides high throughput for the measurement, reconstruction, and trait extraction of rice canopy architectures. The technique provides a more practical method of data collection to serve functional-structural plant models of rice and for the optimization of rice

  19. Reconstruction of blood propagation in three-dimensional rotational X-ray angiography (3D-RA).

    Science.gov (United States)

    Schmitt, Holger; Grass, Michael; Suurmond, Rolf; Köhler, Thomas; Rasche, Volker; Hähnel, Stefan; Heiland, Sabine

    2005-10-01

    This paper presents a framework of non-interactive algorithms for the mapping of blood flow information to vessels in 3D-RA images. With the presented method, mapping of flow information to 3D-RA images is done automatically without user interaction. So far, radiologists had to perform this task by extensive image comparisons and did not obtain visualizations of the results. In our approach, flow information is reconstructed by forward projection of vessel pieces in a 3D-RA image to a two-dimensional projection series capturing the propagation of a short additional contrast agent bolus. For accurate 2D-3D image registration, an efficient patient motion compensation technique is introduced. As an exemplary flow-related quantity, bolus arrival times are reconstructed for the vessel pieces by matching of intensity-time curves. A plausibility check framework was developed which handles projection ambiguities and corrects for noisy flow reconstruction results. It is based on a linear programming approach to model the feeding structure of the vessel. The flow reconstruction method was applied to 12 cases of cerebral stenoses, AVMs and aneurysms, and it proved to be feasible in the clinical environment. The propagation of the injected contrast agent was reconstructed and visualized in three-dimensional images. The flow reconstruction method was able to visualize different types of useful information. In cases of stenosis of the middle cerebral artery (MCA), flow reconstruction can reveal impeded blood flow depending on the severeness of the stenosis. With cases of AVMs, flow reconstruction can clarify the feeding structure. The presented methods handle the problems imposed by clinical demands such as non-interactive algorithms, patient motion compensation, short reconstruction times, and technical requirements such as correction of noisy bolus arrival times and handling of overlapping vessel pieces. Problems occurred mainly in the reconstruction and segmentation of 3D

  20. ENVIRONMENTAL CFD SIMULATION AND VISUALIZATION: EXAMPLES IN SUPPORT OF THE RECONSTRUCTION OF THE SMOKE/DUST PLUME FROM THE WORLD TRADE CENTER SITE FOLLOWING THE EVENTS OF SEPTEMBER 11, 2001

    Science.gov (United States)

    The Poster will present the process of Computational Fluid Dynamics (CFD) simulations through examples supporting the reconstruction of the smoke/dust plumes following the collapse of the WTC towers on September 11, 2001. Understanding the pathway of toxic air polluta...

  1. Convolutional neural network-based encoding and decoding of visual object recognition in space and time.

    Science.gov (United States)

    Seeliger, K; Fritsche, M; Güçlü, U; Schoenmakers, S; Schoffelen, J-M; Bosch, S E; van Gerven, M A J

    2017-07-16

    Representations learned by deep convolutional neural networks (CNNs) for object recognition are a widely investigated model of the processing hierarchy in the human visual system. Using functional magnetic resonance imaging, CNN representations of visual stimuli have previously been shown to correspond to processing stages in the ventral and dorsal streams of the visual system. Whether this correspondence between models and brain signals also holds for activity acquired at high temporal resolution has been explored less exhaustively. Here, we addressed this question by combining CNN-based encoding models with magnetoencephalography (MEG). Human participants passively viewed 1,000 images of objects while MEG signals were acquired. We modelled their high temporal resolution source-reconstructed cortical activity with CNNs, and observed a feed-forward sweep across the visual hierarchy between 75 and 200 ms after stimulus onset. This spatiotemporal cascade was captured by the network layer representations, where the increasingly abstract stimulus representation in the hierarchical network model was reflected in different parts of the visual cortex, following the visual ventral stream. We further validated the accuracy of our encoding model by decoding stimulus identity in a left-out validation set of viewed objects, achieving state-of-the-art decoding accuracy. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Visual analyzer as anticipatory system (functional organization)

    Science.gov (United States)

    Kirvelis, Dobilas

    2000-05-01

    Hypothetical functional organization of the visual analyzer is presented. The interpretation of visual perception, anatomic and morphological structure of visual systems of animals, neuro-physiological, psychological and psycho-physiological data in the light of a number of the theoretical solutions of image recognition and visual processes simulation enable active information processing. The activities in special areas of cortex are as follows: focused attention, prediction with analysis of visual scenes and synthesis, predictive mental images. In the projection zone of visual cortex Area Streata or V1 a "sensory" screen (SS) and "reconstruction" screen (RS) are supposed to exist. The functional structure of visual analyzer consist of: analysis of visual scenes projected onto SS; "tracing" of images; preliminary recognition; reversive image reconstruction onto RS; comparison of images projected onto SS with images reconstructed onto RS; and "correction" of preliminary recognition. Special attention is paid to the quasiholographical principles of the neuronal organization within the brain, of the image "tracing," and of reverse image reconstruction. Tachistoscopic experiments revealed that the duration of one such hypothesis-testing cycle of the human visual analyzers is about 8-10 milliseconds.

  3. Course File for "Documentary Film, Visual Anthropology, and Visual Sociology."

    Science.gov (United States)

    Tomaselli, Keyan G.; Shepperson, Arnold

    1997-01-01

    Describes a course that addresses and relocates questions of representation and reconstruction in the context of reflexive explanations for ethnographic films. Examines questions of power/power relations; anthropological and media construction of the Other; and trends in visual anthropology. Contextualizes the course within the human experience of…

  4. Practical use of visual medial temporal lobe atrophy cut-off scores in Alzheimer's disease: Validation in a large memory clinic population

    Energy Technology Data Exchange (ETDEWEB)

    Claus, Jules J.; Holl, Dana C.; Roorda, Jelmen J. [Tergooi Hospital, Department of Neurology, Blaricum (Netherlands); Staekenborg, Salka S. [Tergooi Hospital, Department of Neurology, Blaricum (Netherlands); VU University Medical Center, Department of Neurology, Alzheimer Center, Amsterdam (Netherlands); Schuur, Jacqueline [Tergooi Hospital, Department of Geriatrics, Blaricum (Netherlands); Koster, Pieter [Tergooi Hospital, Department of Radiology, Blaricum (Netherlands); Tielkes, Caroline E.M. [Tergooi Hospital, Department of Medical Psychology, Blaricum (Netherlands); Scheltens, Philip [VU University Medical Center, Department of Neurology, Alzheimer Center, Amsterdam (Netherlands)

    2017-08-15

    To provide age-specific medial temporal lobe atrophy (MTA) cut-off scores for routine clinical practice as marker for Alzheimer's disease (AD). Patients with AD (n = 832, mean age 81.8 years) were compared with patients with subjective cognitive impairment (n = 333, mean age 71.8 years) in a large single-centre memory clinic. Mean of right and left MTA scores was determined with visual rating (Scheltens scale) using CT (0, no atrophy to 4, severe atrophy). Relationships between age and MTA scores were analysed with regression analysis. For various MTA cut-off scores, decade-specific sensitivity and specificity and area under the curve (AUC) values, computed with receiver operator characteristic curves, were determined. MTA strongly increased with age in both groups to a similar degree. Optimal MTA cut-off values for the age ranges <65, 65-74, 75-84 and ≥85 were: ≥1.0, ≥1.5, ≥ 2.0 and ≥2.0. Corresponding values of sensitivity and specificity were 83.3% and 86.4%; 73.7% and 84.6%; 73.7% and 76.2%; and 84.0% and 62.5%. From this large unique memory clinic cohort we suggest decade-specific MTA cut-off scores for clinical use. After age 85 years, however, the practical usefulness of the MTA cut-off is limited. (orig.)

  5. Cosmography and Data Visualization

    Science.gov (United States)

    Pomarède, Daniel; Courtois, Hélène M.; Hoffman, Yehuda; Tully, R. Brent

    2017-05-01

    Cosmography, the study and making of maps of the universe or cosmos, is a field where visual representation benefits from modern three-dimensional visualization techniques and media. At the extragalactic distance scales, visualization is contributing to our understanding of the complex structure of the local universe in terms of spatial distribution and flows of galaxies and dark matter. In this paper, we report advances in the field of extragalactic cosmography obtained using the SDvision visualization software in the context of the Cosmicflows Project. Here, multiple visualization techniques are applied to a variety of data products: catalogs of galaxy positions and galaxy peculiar velocities, reconstructed velocity field, density field, gravitational potential field, velocity shear tensor viewed in terms of its eigenvalues and eigenvectors, envelope surfaces enclosing basins of attraction. These visualizations, implemented as high-resolution images, videos, and interactive viewers, have contributed to a number of studies: the cosmography of the local part of the universe, the nature of the Great Attractor, the discovery of the boundaries of our home supercluster of galaxies Laniakea, the mapping of the cosmic web, and the study of attractors and repellers.

  6. Anatomical image-guided fluorescence molecular tomography reconstruction using kernel method

    Science.gov (United States)

    Baikejiang, Reheman; Zhao, Yue; Fite, Brett Z.; Ferrara, Katherine W.; Li, Changqing

    2017-05-01

    Fluorescence molecular tomography (FMT) is an important in vivo imaging modality to visualize physiological and pathological processes in small animals. However, FMT reconstruction is ill-posed and ill-conditioned due to strong optical scattering in deep tissues, which results in poor spatial resolution. It is well known that FMT image quality can be improved substantially by applying the structural guidance in the FMT reconstruction. An approach to introducing anatomical information into the FMT reconstruction is presented using the kernel method. In contrast to conventional methods that incorporate anatomical information with a Laplacian-type regularization matrix, the proposed method introduces the anatomical guidance into the projection model of FMT. The primary advantage of the proposed method is that it does not require segmentation of targets in the anatomical images. Numerical simulations and phantom experiments have been performed to demonstrate the proposed approach's feasibility. Numerical simulation results indicate that the proposed kernel method can separate two FMT targets with an edge-to-edge distance of 1 mm and is robust to false-positive guidance and inhomogeneity in the anatomical image. For the phantom experiments with two FMT targets, the kernel method has reconstructed both targets successfully, which further validates the proposed kernel method.

  7. Neuromagnetic source reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, P.S.; Mosher, J.C. [Los Alamos National Lab., NM (United States); Leahy, R.M. [University of Southern California, Los Angeles, CA (United States)

    1994-12-31

    In neuromagnetic source reconstruction, a functional map of neural activity is constructed from noninvasive magnetoencephalographic (MEG) measurements. The overall reconstruction problem is under-determined, so some form of source modeling must be applied. We review the two main classes of reconstruction techniques-parametric current dipole models and nonparametric distributed source reconstructions. Current dipole reconstructions use a physically plausible source model, but are limited to cases in which the neural currents are expected to be highly sparse and localized. Distributed source reconstructions can be applied to a wider variety of cases, but must incorporate an implicit source, model in order to arrive at a single reconstruction. We examine distributed source reconstruction in a Bayesian framework to highlight the implicit nonphysical Gaussian assumptions of minimum norm based reconstruction algorithms. We conclude with a brief discussion of alternative non-Gaussian approachs.

  8. Physically-based in silico light sheet microscopy for visualizing fluorescent brain models.

    Science.gov (United States)

    Abdellah, Marwan; Bilgili, Ahmet; Eilemann, Stefan; Markram, Henry; Schürmann, Felix

    2015-01-01

    We present a physically-based computational model of the light sheet fluorescence microscope (LSFM). Based on Monte Carlo ray tracing and geometric optics, our method simulates the operational aspects and image formation process of the LSFM. This simulated, in silico LSFM creates synthetic images of digital fluorescent specimens that can resemble those generated by a real LSFM, as opposed to established visualization methods producing visually-plausible images. We also propose an accurate fluorescence rendering model which takes into account the intrinsic characteristics of fluorescent dyes to simulate the light interaction with fluorescent biological specimen. We demonstrate first results of our visualization pipeline to a simplified brain tissue model reconstructed from the somatosensory cortex of a young rat. The modeling aspects of the LSFM units are qualitatively analysed, and the results of the fluorescence model were quantitatively validated against the fluorescence brightness equation and characteristic emission spectra of different fluorescent dyes. Modelling and simulation.

  9. High-resolution 3D reconstruction of microtubule structures by quantitative multi-angle total internal reflection fluorescence microscopy

    Science.gov (United States)

    Jin, Luhong; Wu, Jian; Xiu, Peng; Fan, Jiannan; Hu, Miao; Kuang, Cuifang; Xu, Yingke; Zheng, Xiaoxiang; Liu, Xu

    2017-07-01

    Total internal reflection fluorescence microscopy (TIRFM) has been widely used in biomedical research to visualize cellular processes near the cell surface. In this study, a novel multi-angle ring-illuminated TIRFM system, equipped with two galvo mirrors that are on conjugate plan of a 4f optical system was developed. Multi-angle TIRFM generates images with different penetration depths through the controlled variation of the incident angle of illuminating laser. We presented a method to perform three-dimensional (3-D) reconstruction of microtubules from multi-angle TIRFM images. The performance of our method was validated in simulated microtubules with variable signal-to-noise ratios (SNR) and the axial resolution and accuracy of reconstruction were evaluated in selecting different numbers of illumination angles or in different SNR conditions. In U373 cells, we reconstructed the 3-D localization of microtubules near the cell surface with high resolution using over a hundred different angles. Theoretically, the presented TIRFM setup and 3-D reconstruction method can achieve 40 nm axial resolution in experimental conditions where SNR is as low as 2, with 35 different illumination angles. Moreover, our system and reconstruction method have the potential to be used in live cells to track membrane dynamics in 3-D.

  10. Visual art and visual perception

    NARCIS (Netherlands)

    Koenderink, Jan J.

    2015-01-01

    Visual art and visual perception ‘Visual art’ has become a minor cul-de-sac orthogonal to THE ART of the museum directors and billionaire collectors. THE ART is conceptual, instead of visual. Among its cherished items are the tins of artist’s shit (Piero Manzoni, 1961, Merda d’Artista) “worth their

  11. AUTOMATIC FUSION OF PARTIAL RECONSTRUCTIONS

    Directory of Open Access Journals (Sweden)

    A. Wendel

    2012-07-01

    Full Text Available Novel image acquisition tools such as micro aerial vehicles (MAVs in form of quad- or octo-rotor helicopters support the creation of 3D reconstructions with ground sampling distances below 1 cm. The limitation of aerial photogrammetry to nadir and oblique views in heights of several hundred meters is bypassed, allowing close-up photos of facades and ground features. However, the new acquisition modality also introduces challenges: First, flight space might be restricted in urban areas, which leads to missing views for accurate 3D reconstruction and causes fracturing of large models. This could also happen due to vegetation or simply a change of illumination during image acquisition. Second, accurate geo-referencing of reconstructions is difficult because of shadowed GPS signals in urban areas, so alignment based on GPS information is often not possible. In this paper, we address the automatic fusion of such partial reconstructions. Our approach is largely based on the work of (Wendel et al., 2011a, but does not require an overhead digital surface model for fusion. Instead, we exploit that patch-based semi-dense reconstruction of the fractured model typically results in several point clouds covering overlapping areas, even if sparse feature correspondences cannot be established. We approximate orthographic depth maps for the individual parts and iteratively align them in a global coordinate system. As a result, we are able to generate point clouds which are visually more appealing and serve as an ideal basis for further processing. Mismatches between parts of the fused models depend only on the individual point density, which allows us to achieve a fusion accuracy in the range of ±1 cm on our evaluation dataset.

  12. RECONSTRUCTION OF BUILDING FOOTPRINTS USING SPACEBORNE TOMOSAR POINT CLOUDS

    Directory of Open Access Journals (Sweden)

    M. Shahzad

    2015-08-01

    Full Text Available This paper presents an approach that automatically (but parametrically reconstructs 2-D/3-D building footprints using 3-D synthetic aperture radar (SAR tomography (TomoSAR point clouds. These point clouds are generated by processing SAR image stacks via SAR tomographic inversion. The proposed approach reconstructs the building outline by exploiting both the roof and façade points. Initial building footprints are derived by applying the alpha shapes method on pre-segmented point clusters of individual buildings. A recursive angular deviation based refinement is then carried out to obtain refined/smoothed 2-D polygonal boundaries. A robust fusion framework then fuses the information pertaining to building façades to the smoothed polygons. Afterwards, a rectilinear building identification procedure is adopted and constraints are added to yield geometrically correct and visually aesthetic building shapes. The proposed approach is illustrated and validated using TomoSAR point clouds generated from a stack of TerraSAR-X high-resolution spotlight images from ascending orbit covering approximately 1.5 km2 area in the city of Berlin, Germany.

  13. Reconstruction of Building Footprints Using Spaceborne Tomosar Point Clouds

    Science.gov (United States)

    Shahzad, M.; Zhu, X. X.

    2015-08-01

    This paper presents an approach that automatically (but parametrically) reconstructs 2-D/3-D building footprints using 3-D synthetic aperture radar (SAR) tomography (TomoSAR) point clouds. These point clouds are generated by processing SAR image stacks via SAR tomographic inversion. The proposed approach reconstructs the building outline by exploiting both the roof and façade points. Initial building footprints are derived by applying the alpha shapes method on pre-segmented point clusters of individual buildings. A recursive angular deviation based refinement is then carried out to obtain refined/smoothed 2-D polygonal boundaries. A robust fusion framework then fuses the information pertaining to building façades to the smoothed polygons. Afterwards, a rectilinear building identification procedure is adopted and constraints are added to yield geometrically correct and visually aesthetic building shapes. The proposed approach is illustrated and validated using TomoSAR point clouds generated from a stack of TerraSAR-X high-resolution spotlight images from ascending orbit covering approximately 1.5 km2 area in the city of Berlin, Germany.

  14. POSTERIOR INTEROSSEOUS FLAP IN PEDIATRIC HAND RECONSTRUCTIONS

    Directory of Open Access Journals (Sweden)

    I. O. Golubev

    2014-01-01

    Full Text Available Purpose: to assess early and long-term results of the pediatric hand reconstructions with posterior interosseous flap, including those in children younger than 3 years old. Materials and methods: results of the hand reconstructions with posterior interosseous artery reverse flap were studied in 10 children (4 males and 6 females aged from 1 year and 1 month to 13 years old. In 4 cases flap coverage were performed due to acquired posttraumatic hand deformity, in 6 cases reconstruction was assumed for congenital hand deformities. Combined procedures consisted of posterior interosseous artery flap coverage and other types of microsurgical reconstructions were suggested in 4 patients. Preoperative color doppler visualization of the posterior interosseous vessels were mandatory. All flaps were risen under 3.5x-4.5x magnification. Results: all flaps survived completely in 3 weeks postoperatively. There were no postoperative complications such as flap’s arterial or venous insufficiency, deep infection, or posterior interosseous nerve palsy. Nearly whole group (9 of 10 of patients and/or their parents were satisfied with the esthetic view of the reconstructed hand and donor site of the forearm 1 year postoperatively. Conclusion: posterior interosseous flap is a reliable and versatile option in pediatric hand reconstructions, providing excellent skin coverage with good color match and texture. Preservation of major vascular bundles of the forearm (radial and ulnar arteries during flap harvest gives a possibility to perform a simultaneous microsurgical reconstructions of the hand (e.g. free toe transfer.

  15. A multicenter study on the validation of the Burnout Battery: a new visual analog scale to screen job burnout in oncology professionals.

    Science.gov (United States)

    Deng, Yao-Tiao; Liu, Jie; Zhang, Jie; Huang, Bo-Yan; Yi, Ting-Wu; Wang, Yu-Qing; Zheng, Bo; Luo, Di; Du, Pei-Xin; Jiang, Yu

    2017-08-01

    The objective of the study is to develop a novel tool-the Burnout Battery-for briefly screening burnout among oncology professionals in China and assessing its validity. A multicenter study was conducted in doctors and nurses of the oncology departments in China from November 2014 to May 2015. The Burnout Battery was administered with the Maslach Burnout Inventory-Human Services Survey (MBI-HSS) and the Doctors' Job Burnout Questionnaire. Of 538 oncology doctors and nurses who completed all the survey, using MBI-HSS as the standard tool for measuring burnout, 52% had emotional exhaustion, 39.4% had depersonalization, and 59.3% had a low sense of personal accomplishment. Receiver operating characteristic curve analyses showed that the best cut-off of the Burnout Battery was the battery with 3 bars, which yielded best sensitivity and specificity against all the 3 subscales of MBI-HSS. With this cut-off, nearly half of Chinese oncology professionals (46.8%) had burnout. The Burnout Battery correlated significantly with subscales of the MBI-HSS and the Doctors' Job Burnout Questionnaire. In multiple logistic regression analysis, those who worked more than 60 hours per week and who thought clinical work was the most stressful part of their job were more likely to experience burnout. Chinese oncology professionals exhibit high levels of burnout. The Burnout Battery appears to be a simple and useful tool for screening burnout. Working long hours and perceiving clinical work as the most stressful part of the job were the main factors associated with burnout. Copyright © 2016 John Wiley & Sons, Ltd.

  16. Flow visualization

    CERN Document Server

    Merzkirch, Wolfgang

    1974-01-01

    Flow Visualization describes the most widely used methods for visualizing flows. Flow visualization evaluates certain properties of a flow field directly accessible to visual perception. Organized into five chapters, this book first presents the methods that create a visible flow pattern that could be investigated by visual inspection, such as simple dye and density-sensitive visualization methods. It then deals with the application of electron beams and streaming birefringence. Optical methods for compressible flows, hydraulic analogy, and high-speed photography are discussed in other cha

  17. Breast reconstruction - natural tissue

    Science.gov (United States)

    ... muscle flap; TRAM; Latissimus muscle flap with a breast implant; DIEP flap; DIEAP flap; Gluteal free flap; Transverse upper gracilis flap; TUG; Mastectomy - breast reconstruction with natural tissue; Breast cancer - breast reconstruction ...

  18. Head and face reconstruction

    Science.gov (United States)

    ... medlineplus.gov/ency/article/002980.htm Head and face reconstruction To use the sharing features on this page, please enable JavaScript. Head and face reconstruction is surgery to repair or reshape deformities ...

  19. Network reconstruction via density sampling

    CERN Document Server

    Squartini, Tiziano; Gabrielli, Andrea; Garlaschelli, Diego

    2016-01-01

    Reconstructing weighted networks from partial information is necessary in many important circumstances, e.g. for a correct estimation of systemic risk. It has been shown that, in order to achieve an accurate reconstruction, it is crucial to reliably replicate the empirical degree sequence, which is however unknown in many realistic situations. More recently, it has been found that the knowledge of the degree sequence can be replaced by the knowledge of the strength sequence, which is typically accessible, complemented by that of the total number of links, thus considerably relaxing the observational requirements. Here we further relax these requirements and devise a procedure valid when even the the total number of links is unavailable. We assume that, apart from the heterogeneity induced by the degree sequence itself, the network is homogeneous, so that its link density can be estimated by sampling subsets of nodes with representative density. We show that the best way of sampling nodes is the random selecti...

  20. Performance-based assessment of reconstructed images

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Kenneth [Los Alamos National Laboratory

    2009-01-01

    During the early 90s, I engaged in a productive and enjoyable collaboration with Robert Wagner and his colleague, Kyle Myers. We explored the ramifications of the principle that tbe quality of an image should be assessed on the basis of how well it facilitates the performance of appropriate visual tasks. We applied this principle to algorithms used to reconstruct scenes from incomplete and/or noisy projection data. For binary visual tasks, we used both the conventional disk detection and a new challenging task, inspired by the Rayleigh resolution criterion, of deciding whether an object was a blurred version of two dots or a bar. The results of human and machine observer tests were summarized with the detectability index based on the area under the ROC curve. We investigated a variety of reconstruction algorithms, including ART, with and without a nonnegativity constraint, and the MEMSYS3 algorithm. We concluded that the performance of the Raleigh task was optimized when the strength of the prior was near MEMSYS's default 'classic' value for both human and machine observers. A notable result was that the most-often-used metric of rms error in the reconstruction was not necessarily indicative of the value of a reconstructed image for the purpose of performing visual tasks.

  1. Cartographic visualization

    NARCIS (Netherlands)

    Kraak, M.J.; Wright, James D.

    2015-01-01

    The cartographic visualization process, based on the statement “How do I say what to whom, and is it effective?” is explained for both presenting and exploring spatiotemporal data. The visualization environment and required functionality are described

  2. Adaptive semantics visualization

    CERN Document Server

    Nazemi, Kawa

    2016-01-01

    This book introduces a novel approach for intelligent visualizations that adapts the different visual variables and data processing to human’s behavior and given tasks. Thereby a number of new algorithms and methods are introduced to satisfy the human need of information and knowledge and enable a usable and attractive way of information acquisition. Each method and algorithm is illustrated in a replicable way to enable the reproduction of the entire “SemaVis” system or parts of it. The introduced evaluation is scientifically well-designed and performed with more than enough participants to validate the benefits of the methods. Beside the introduced new approaches and algorithms, readers may find a sophisticated literature review in Information Visualization and Visual Analytics, Semantics and information extraction, and intelligent and adaptive systems. This book is based on an awarded and distinguished doctoral thesis in computer science.

  3. Tensor-based dynamic reconstruction method for electrical capacitance tomography

    Science.gov (United States)

    Lei, J.; Mu, H. P.; Liu, Q. B.; Li, Z. H.; Liu, S.; Wang, X. Y.

    2017-03-01

    Electrical capacitance tomography (ECT) is an attractive visualization measurement method, in which the acquisition of high-quality images is beneficial for the understanding of the underlying physical or chemical mechanisms of the dynamic behaviors of the measurement objects. In real-world measurement environments, imaging objects are often in a dynamic process, and the exploitation of the spatial-temporal correlations related to the dynamic nature will contribute to improving the imaging quality. Different from existing imaging methods that are often used in ECT measurements, in this paper a dynamic image sequence is stacked into a third-order tensor that consists of a low rank tensor and a sparse tensor within the framework of the multiple measurement vectors model and the multi-way data analysis method. The low rank tensor models the similar spatial distribution information among frames, which is slowly changing over time, and the sparse tensor captures the perturbations or differences introduced in each frame, which is rapidly changing over time. With the assistance of the Tikhonov regularization theory and the tensor-based multi-way data analysis method, a new cost function, with the considerations of the multi-frames measurement data, the dynamic evolution information of a time-varying imaging object and the characteristics of the low rank tensor and the sparse tensor, is proposed to convert the imaging task in the ECT measurement into a reconstruction problem of a third-order image tensor. An effective algorithm is developed to search for the optimal solution of the proposed cost function, and the images are reconstructed via a batching pattern. The feasibility and effectiveness of the developed reconstruction method are numerically validated.

  4. Visual Scripting.

    Science.gov (United States)

    Halas, John

    Visual scripting is the coordination of words with pictures in sequence. This book presents the methods and viewpoints on visual scripting of fourteen film makers, from nine countries, who are involved in animated cinema; it contains concise examples of how a storybook and preproduction script can be prepared in visual terms; and it includes a…

  5. Simultaneous Reconstruction and Segmentation with Class-Specific Priors

    DEFF Research Database (Denmark)

    Romanov, Mikhail

    Studying the interior of objects using tomography often require an image segmentation, such that different material properties can be quantified. This can for example be volume or surface area. Segmentation is typically done as an image analysis step after the image has been reconstructed....... This thesis investigates computing the reconstruction and segmentation simultaneously. The advantage of this is that because the reconstruction and segmentation are computed jointly, reconstruction errors are not propagated to the segmentation step. Furthermore the segmentation procedure can be used...... for regularizing the reconstruction process. The thesis provides models and algorithms for simultaneous reconstruction and segmentation and their performance is empirically validated. Two method of simultaneous reconstruction and segmentation are described in the thesis. Also, a method for parameter selection...

  6. Region-of-interest volumetric visual hull refinement

    KAUST Repository

    Knoblauch, Daniel

    2010-01-01

    This paper introduces a region-of-interest visual hull refinement technique, based on flexible voxel grids for volumetric visual hull reconstructions. Region-of-interest refinement is based on a multipass process, beginning with a focussed visual hull reconstruction, resulting in a first 3D approximation of the target, followed by a region-of-interest estimation, tasked with identifying features of interest, which in turn are used to locally refine the voxel grid and extract a higher-resolution surface representation for those regions. This approach is illustrated for the reconstruction of avatars for use in tele-immersion environments, where head and hand regions are of higher interest. To allow reproducability and direct comparison a publicly available data set for human visual hull reconstruction is used. This paper shows that region-of-interest reconstruction of the target is faster and visually comparable to higher resolution focused visual hull reconstructions. This approach reduces the amount of data generated through the reconstruction, allowing faster post processing, as rendering or networking of the surface voxels. Reconstruction speeds support smooth interactions between the avatar and the virtual environment, while the improved resolution of its facial region and hands creates a higher-degree of immersion and potentially impacts the perception of body language, facial expressions and eye-to-eye contact. Copyright © 2010 by the Association for Computing Machinery, Inc.

  7. Accelerating Popular Tomographic Reconstruction Algorithms on Commodity PC Graphics Hardware

    Science.gov (United States)

    Xu, Fang; Mueller, K.

    2005-06-01

    The task of reconstructing an object from its projections via tomographic methods is a time-consuming process due to the vast complexity of the data. For this reason, manufacturers of equipment for medical computed tomography (CT) rely mostly on special application specified integrated circuits (ASICs) to obtain the fast reconstruction times required in clinical settings. Although modern CPUs have gained sufficient power in recent years to be competitive for two-dimensional (2D) reconstruction, this is not the case for three-dimensional (3D) reconstructions, especially not when iterative algorithms must be applied. The recent evolution of commodity PC computer graphics boards (GPUs) has the potential to change this picture in a very dramatic way. In this paper we will show how the new floating point GPUs can be exploited to perform both analytical and iterative reconstruction from X-ray and functional imaging data. For this purpose, we decompose three popular three-dimensional (3D) reconstruction algorithms (Feldkamp filtered backprojection, the simultaneous algebraic reconstruction technique, and expectation maximization) into a common set of base modules, which all can be executed on the GPU and their output linked internally. Visualization of the reconstructed object is easily achieved since the object already resides in the graphics hardware, allowing one to run a visualization module at any time to view the reconstruction results. Our implementation allows speedups of over an order of magnitude with respect to CPU implementations, at comparable image quality.

  8. constrained multiplicative algebraic reconstruction technique (CMART)

    Indian Academy of Sciences (India)

    lems widely used in medical applications, where transform-based ... puter tomography in medical applications (Zhai and Cummer 2005). .... The error compari- son of two reconstruction algorithms validated that. CMART was superior to MART algorithm. To simplify the description, in the following section, one-iteration means ...

  9. Data visualization

    CERN Document Server

    Azzam, Tarek

    2013-01-01

    Do you communicate data and information to stakeholders? In Part 1, we introduce recent developments in the quantitative and qualitative data visualization field and provide a historical perspective on data visualization, its potential role in evaluation practice, and future directions. Part 2 delivers concrete suggestions for optimally using data visualization in evaluation, as well as suggestions for best practices in data visualization design. It focuses on specific quantitative and qualitative data visualization approaches that include data dashboards, graphic recording, and geographic information systems (GIS). Readers will get a step-by-step process for designing an effective data dashboard system for programs and organizations, and various suggestions to improve their utility.

  10. Validation of a method for in vivo 3D dose reconstruction for IMRT and VMAT treatments using on-treatment EPID images and a model-based forward-calculation algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Van Uytven, Eric, E-mail: eric.vanuytven@cancercare.mb.ca; Van Beek, Timothy [Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); McCowan, Peter M. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada and Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); Chytyk-Praznik, Krista [Medical Physics Department, Nova Scotia Cancer Centre, 5820 University Avenue, Halifax, Nova Scotia B3H 1V7 (Canada); Greer, Peter B. [School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, NSW 2308 (Australia); Department of Radiation Oncology, Calvary Mater Newcastle Hospital, Newcastle, NSW 2298 (Australia); McCurdy, Boyd M. C. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); Department of Radiology, University of Manitoba, 820 Sherbrook Street, Winnipeg, Manitoba R3A 1R9 (Canada)

    2015-12-15

    Purpose: Radiation treatments are trending toward delivering higher doses per fraction under stereotactic radiosurgery and hypofractionated treatment regimens. There is a need for accurate 3D in vivo patient dose verification using electronic portal imaging device (EPID) measurements. This work presents a model-based technique to compute full three-dimensional patient dose reconstructed from on-treatment EPID portal images (i.e., transmission images). Methods: EPID dose is converted to incident fluence entering the patient using a series of steps which include converting measured EPID dose to fluence at the detector plane and then back-projecting the primary source component of the EPID fluence upstream of the patient. Incident fluence is then recombined with predicted extra-focal fluence and used to calculate 3D patient dose via a collapsed-cone convolution method. This method is implemented in an iterative manner, although in practice it provides accurate results in a single iteration. The robustness of the dose reconstruction technique is demonstrated with several simple slab phantom and nine anthropomorphic phantom cases. Prostate, head and neck, and lung treatments are all included as well as a range of delivery techniques including VMAT and dynamic intensity modulated radiation therapy (IMRT). Results: Results indicate that the patient dose reconstruction algorithm compares well with treatment planning system computed doses for controlled test situations. For simple phantom and square field tests, agreement was excellent with a 2%/2 mm 3D chi pass rate ≥98.9%. On anthropomorphic phantoms, the 2%/2 mm 3D chi pass rates ranged from 79.9% to 99.9% in the planning target volume (PTV) region and 96.5% to 100% in the low dose region (>20% of prescription, excluding PTV and skin build-up region). Conclusions: An algorithm to reconstruct delivered patient 3D doses from EPID exit dosimetry measurements was presented. The method was applied to phantom and patient

  11. Validation of a method for in vivo 3D dose reconstruction for IMRT and VMAT treatments using on-treatment EPID images and a model-based forward-calculation algorithm.

    Science.gov (United States)

    Van Uytven, Eric; Van Beek, Timothy; McCowan, Peter M; Chytyk-Praznik, Krista; Greer, Peter B; McCurdy, Boyd M C

    2015-12-01

    Radiation treatments are trending toward delivering higher doses per fraction under stereotactic radiosurgery and hypofractionated treatment regimens. There is a need for accurate 3D in vivo patient dose verification using electronic portal imaging device (EPID) measurements. This work presents a model-based technique to compute full three-dimensional patient dose reconstructed from on-treatment EPID portal images (i.e., transmission images). EPID dose is converted to incident fluence entering the patient using a series of steps which include converting measured EPID dose to fluence at the detector plane and then back-projecting the primary source component of the EPID fluence upstream of the patient. Incident fluence is then recombined with predicted extra-focal fluence and used to calculate 3D patient dose via a collapsed-cone convolution method. This method is implemented in an iterative manner, although in practice it provides accurate results in a single iteration. The robustness of the dose reconstruction technique is demonstrated with several simple slab phantom and nine anthropomorphic phantom cases. Prostate, head and neck, and lung treatments are all included as well as a range of delivery techniques including VMAT and dynamic intensity modulated radiation therapy (IMRT). Results indicate that the patient dose reconstruction algorithm compares well with treatment planning system computed doses for controlled test situations. For simple phantom and square field tests, agreement was excellent with a 2%/2 mm 3D chi pass rate ≥98.9%. On anthropomorphic phantoms, the 2%/2 mm 3D chi pass rates ranged from 79.9% to 99.9% in the planning target volume (PTV) region and 96.5% to 100% in the low dose region (>20% of prescription, excluding PTV and skin build-up region). An algorithm to reconstruct delivered patient 3D doses from EPID exit dosimetry measurements was presented. The method was applied to phantom and patient data sets, as well as for dynamic IMRT and

  12. Visual agnosia.

    Science.gov (United States)

    Álvarez, R; Masjuan, J

    2016-03-01

    Visual agnosia is defined as an impairment of object recognition, in the absence of visual acuity or cognitive dysfunction that would explain this impairment. This condition is caused by lesions in the visual association cortex, sparing primary visual cortex. There are 2 main pathways that process visual information: the ventral stream, tasked with object recognition, and the dorsal stream, in charge of locating objects in space. Visual agnosia can therefore be divided into 2 major groups depending on which of the two streams is damaged. The aim of this article is to conduct a narrative review of the various visual agnosia syndromes, including recent developments in a number of these syndromes. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Medicina Interna (SEMI). All rights reserved.

  13. VALIDEZ DE LA ESTIMACIÓN VISUAL COMO MÉTODO DIAGNÓSTICO DE LA HEMORRAGIA POSTPARTO SEVERA EN UN HOSPITAL UNIVERSITARIO. BOGOTÁ. 2007 Validity of visual estimation of blood loss as diagnostic tool in severe post partum hemorrhage in an university hospital. Bogotá. 2007

    Directory of Open Access Journals (Sweden)

    Jorge Andrés Rubio-Romero

    2010-07-01

    immediately after vaginal delivery. Material and methods. A diagnostic accuracy study was carried out in a cohort of pregnant women who had a vaginal delivery at an university hospital. It was approved by the ethics and investigation committees of participating institutions. A complex gold standard combining clinical and laboratory signs was defined: need of therapeutic maneuvers for treatment of post partum hemorrhage, drop of 10% or more of previous hematocrit or need of transfusion. Results. Incidence of SPPH was 10,7% of the 168 patients included. Median volume of estimated blood loss was 375 mL while median real observed blood volume was 475 mL. For the diagnosis of SPPH, estimated blood loss greater than 500 mL had a sensitivity and specificity of 77,8 y 73,3% respectively. For estimated blood loss greater than 800 mL, sensitivity and specificity were 44,4 and 94%. This cut point is the one that better classifies puerperal women requiring initial treatment for diagnose an abnormal hemorrhage of the post partum. Conclusions. Visual estimation of blood loss during delivery is a poorly sensitive and specific diagnostic test for the diagnosis of SPPH due to underestimation of the real magnitude of the blood loss occurred. Key words: validity of tests, reproducibility of results, sensitivity and specificity, postpartum hemorrhage. Rubio-Romero JA, Guevara-Cruz OA, Gaitán- Duarte H. Validity of visual estimation of blood loss as diagnostic tool in severe post partum hemorrhage in an university hospital. Bogotá. 2007. Rev.Fac.Med. 2010; 58: 173-184.

  14. Experimenting with Visual Storytelling in Students' Portfolios: Narratives of Visual Pedagogy for Pre-Service Teacher Education

    Science.gov (United States)

    Rifa-Valls, Montserrat

    2011-01-01

    This article interprets the repercussions of visual storytelling for art education and arts-based narrative research and, particularly, it approaches visual storytelling as a critical tool for pre-service teacher education. After reinterpreting storytelling from the perspective of visual critical pedagogy, I will narratively reconstruct the use of…

  15. An automatic virtual patient reconstruction from CT-scans for hepatic surgical planning.

    Science.gov (United States)

    Soler, L; Delingette, H; Malandain, G; Ayache, N; Koehl, C; Clément, J M; Dourthe, O; Marescaux, J

    2000-01-01

    PROBLEM/BACKGROUND: In order to help hepatic surgical planning we perfected automatic 3D reconstruction of patients from conventional CT-scan, and interactive visualization and virtual resection tools. From a conventional abdominal CT-scan, we have developed several methods allowing the automatic 3D reconstruction of skin, bones, kidneys, lung, liver, hepatic lesions, and vessels. These methods are based on deformable modeling or thresholding algorithms followed by the application of mathematical morphological operators. From these anatomical and pathological models, we have developed a new framework for translating anatomical knowledge into geometrical and topological constraints. More precisely, our approach allows to automatically delineate the hepatic and portal veins but also to label the portal vein and finally to build an anatomical segmentation of the liver based on Couinaud definition which is currently used by surgeons all over the world. Finally, we have developed a user friendly interface for the 3D visualization of anatomical and pathological structures, the accurate evaluation of volumes and distances and for the virtual hepatic resection along a user-defined cutting plane. A validation study on a 30 patients database gives 2 mm of precision for liver delineation and less than 1 mm for all other anatomical and pathological structures delineation. An in vivo validation performed during surgery also showed that anatomical segmentation is more precise than the delineation performed by a surgeon based on external landmarks. This surgery planning system has been routinely used by our medical partner, and this has resulted in an improvement of the planning and performance of hepatic surgery procedures. We have developed new tools for hepatic surgical planning allowing a better surgery through an automatic delineation and visualization of anatomical and pathological structures. These tools represent a first step towards the development of an augmented

  16. Clinical validation of high-resolution image reconstruction algorithms in brain 18F-FDG-PET: effect of incorporating Gaussian filter, point spread function, and time-of-flight.

    Science.gov (United States)

    Nagaki, Akio; Onoguchi, Masahisa; Matsutomo, Norikazu

    2014-12-01

    Accurate estimation of radiopharmaceutical uptake in the brain is difficult because of count statistics, low spatial resolution, and smoothing filter. The aim of this study was to assess the counting rate performance of PET scanners and the image quality with different combinations of high-resolution image reconstruction algorithms in brain F-2-fluorodeoxy-D-glucose (F-FDG)-PET. Using 23 patient studies, we analyzed the coincidence rates of true and random, random fraction, and the noise equivalent counts per axial length (NECpatient) in brain and liver bed positions. The reconstruction algorithms were combined with baseline ordered subsets expectation maximization, Gaussian filter (GF), point spread function (PSF), and time-of-flight (TOF). The image quality of the brain cortex was quantitatively evaluated with respect to spatial resolution, contrast, and signal-to-noise ratio (SNR). The true coincidence rate in the brain was higher by 1.86 times and the random coincidence rate was lower by 0.61 times compared with that in the liver. In the brain, random fraction was lower and NECpatient was higher than that of the liver. Although GF improved the SNR, spatial resolution and contrast were reduced by 12 and 11%, respectively (P<0.01). PSF improved spatial resolution and SNR by 11 and 53%, respectively (P<0.01), and TOF improved SNR by ∼23% (P<0.01). We have demonstrated that a high-resolution image reconstruction algorithm for brain F-FDG-PET is promising without the use of a GF because of high true coincidence counts and that combined with PSF and TOF is optimal for obtaining a better SNR of the image.

  17. Improving Visibility of Stereo-Radiographic Spine Reconstruction with Geometric Inferences.

    Science.gov (United States)

    Kumar, Sampath; Nayak, K Prabhakar; Hareesha, K S

    2016-04-01

    Complex deformities of the spine, like scoliosis, are evaluated more precisely using stereo-radiographic 3D reconstruction techniques. Primarily, it uses six stereo-corresponding points available on the vertebral body for the 3D reconstruction of each vertebra. The wireframe structure obtained in this process has poor visualization, hence difficult to diagnose. In this paper, a novel method is proposed to improve the visibility of this wireframe structure using a deformation of a generic spine model in accordance with the 3D-reconstructed corresponding points. Then, the geometric inferences like vertebral orientations are automatically extracted from the radiographs to improve the visibility of the 3D model. Biplanar radiographs are acquired from five scoliotic subjects on a specifically designed calibration bench. The stereo-corresponding point reconstruction method is used to build six-point wireframe vertebral structures and thus the entire spine model. Using the 3D spine midline and automatically extracted vertebral orientation features, a more realistic 3D spine model is generated. To validate the method, the 3D spine model is back-projected on biplanar radiographs and the error difference is computed. Though, this difference is within the error limits available in the literature, the proposed work is simple and economical. The proposed method does not require more corresponding points and image features to improve the visibility of the model. Hence, it reduces the computational complexity. Expensive 3D digitizer and vertebral CT scan models are also excluded from this study. Thus, the visibility of stereo-corresponding point reconstruction is improved to obtain a low-cost spine model for a better diagnosis of spinal deformities.

  18. Rapid reconstruction of 3D neuronal morphology from light microscopy images with augmented rayburst sampling.

    Directory of Open Access Journals (Sweden)

    Xing Ming

    Full Text Available Digital reconstruction of three-dimensional (3D neuronal morphology from light microscopy images provides a powerful technique for analysis of neural circuits. It is time-consuming to manually perform this process. Thus, efficient computer-assisted approaches are preferable. In this paper, we present an innovative method for the tracing and reconstruction of 3D neuronal morphology from light microscopy images. The method uses a prediction and refinement strategy that is based on exploration of local neuron structural features. We extended the rayburst sampling algorithm to a marching fashion, which starts from a single or a few seed points and marches recursively forward along neurite branches to trace and reconstruct the whole tree-like structure. A local radius-related but size-independent hemispherical sampling was used to predict the neurite centerline and detect branches. Iterative rayburst sampling was performed in the orthogonal plane, to refine the centerline location and to estimate the local radius. We implemented the method in a cooperative 3D interactive visualization-assisted system named flNeuronTool. The source code in C++ and the binaries are freely available at http://sourceforge.net/projects/flneurontool/. We validated and evaluated the proposed method using synthetic data and real datasets from the Digital Reconstruction of Axonal and Dendritic Morphology (DIADEM challenge. Then, flNeuronTool was applied to mouse brain images acquired with the Micro-Optical Sectioning Tomography (MOST system, to reconstruct single neurons and local neural circuits. The results showed that the system achieves a reasonable balance between fast speed and acceptable accuracy, which is promising for interactive applications in neuronal image analysis.

  19. Low Dose PET Image Reconstruction with Total Variation Using Alternating Direction Method.

    Directory of Open Access Journals (Sweden)

    Xingjian Yu

    Full Text Available In this paper, a total variation (TV minimization strategy is proposed to overcome the problem of sparse spatial resolution and large amounts of noise in low dose positron emission tomography (PET imaging reconstruction. Two types of objective function were established based on two statistical models of measured PET data, least-square (LS TV for the Gaussian distribution and Poisson-TV for the Poisson distribution. To efficiently obtain high quality reconstructed images, the alternating direction method (ADM is used to solve these objective functions. As compared with the iterative shrinkage/thresholding (IST based algorithms, the proposed ADM can make full use of the TV constraint and its convergence rate is faster. The performance of the proposed approach is validated through comparisons with the expectation-maximization (EM method using synthetic and experimental biological data. In the comparisons, the results of both LS-TV and Poisson-TV are taken into consideration to find which models are more suitable for PET imaging, in particular low-dose PET. To evaluate the results quantitatively, we computed bias, variance, and the contrast recovery coefficient (CRC and drew profiles of the reconstructed images produced by the different methods. The results show that both Poisson-TV and LS-TV can provide a high visual quality at a low dose level. The bias and variance of the proposed LS-TV and Poisson-TV methods are 20% to 74% less at all counting levels than those of the EM method. Poisson-TV gives the best performance in terms of high-accuracy reconstruction with the lowest bias and variance as compared to the ground truth (14.3% less bias and 21.9% less variance. In contrast, LS-TV gives the best performance in terms of the high contrast of the reconstruction with the highest CRC.

  20. Dense soft tissue 3D reconstruction refined with super-pixel segmentation for robotic abdominal surgery.

    Science.gov (United States)

    Penza, Veronica; Ortiz, Jesús; Mattos, Leonardo S; Forgione, Antonello; De Momi, Elena

    2016-02-01

    Single-incision laparoscopic surgery decreases postoperative infections, but introduces limitations in the surgeon's maneuverability and in the surgical field of view. This work aims at enhancing intra-operative surgical visualization by exploiting the 3D information about the surgical site. An interactive guidance system is proposed wherein the pose of preoperative tissue models is updated online. A critical process involves the intra-operative acquisition of tissue surfaces. It can be achieved using stereoscopic imaging and 3D reconstruction techniques. This work contributes to this process by proposing new methods for improved dense 3D reconstruction of soft tissues, which allows a more accurate deformation identification and facilitates the registration process. Two methods for soft tissue 3D reconstruction are proposed: Method 1 follows the traditional approach of the block matching algorithm. Method 2 performs a nonparametric modified census transform to be more robust to illumination variation. The simple linear iterative clustering (SLIC) super-pixel algorithm is exploited for disparity refinement by filling holes in the disparity images. The methods were validated using two video datasets from the Hamlyn Centre, achieving an accuracy of 2.95 and 1.66 mm, respectively. A comparison with ground-truth data demonstrated the disparity refinement procedure: (1) increases the number of reconstructed points by up to 43 % and (2) does not affect the accuracy of the 3D reconstructions significantly. Both methods give results that compare favorably with the state-of-the-art methods. The computational time constraints their applicability in real time, but can be greatly improved by using a GPU implementation.

  1. Assessment of visual disability using visual evoked potentials.

    Science.gov (United States)

    Jeon, Jihoon; Oh, Seiyul; Kyung, Sungeun

    2012-08-06

    The purpose of this study is to validate the use of visual evoked potential (VEP) to objectively quantify visual acuity in normal and amblyopic patients, and determine if it is possible to predict visual acuity in disability assessment to register visual pathway lesions. A retrospective chart review was conducted of patients diagnosed with normal vision, unilateral amblyopia, optic neuritis, and visual disability who visited the university medical center for registration from March 2007 to October 2009. The study included 20 normal subjects (20 right eyes: 10 females, 10 males, ages 9-42 years), 18 unilateral amblyopic patients (18 amblyopic eyes, ages 19-36 years), 19 optic neuritis patients (19 eyes: ages 9-71 years), and 10 patients with visual disability having visual pathway lesions. Amplitude and latencies were analyzed and correlations with visual acuity (logMAR) were derived from 20 normal and 18 amblyopic subjects. Correlation of VEP amplitude and visual acuity (logMAR) of 19 optic neuritis patients confirmed relationships between visual acuity and amplitude. We calculated the objective visual acuity (logMAR) of 16 eyes from 10 patients to diagnose the presence or absence of visual disability using relations derived from 20 normal and 18 amblyopic eyes. Linear regression analyses between amplitude of pattern visual evoked potentials and visual acuity (logMAR) of 38 eyes from normal (right eyes) and amblyopic (amblyopic eyes) subjects were significant [y = -0.072x + 1.22, x: VEP amplitude, y: visual acuity (logMAR)]. There were no significant differences between visual acuity prediction values, which substituted amplitude values of 19 eyes with optic neuritis into function. We calculated the objective visual acuity of 16 eyes of 10 patients to diagnose the presence or absence of visual disability using relations of y = -0.072x + 1.22 (-0.072). This resulted in a prediction reference of visual acuity associated with malingering vs. real

  2. Assessment of visual disability using visual evoked potentials

    Directory of Open Access Journals (Sweden)

    Jeon Jihoon

    2012-08-01

    Full Text Available Abstract Background The purpose of this study is to validate the use of visual evoked potential (VEP to objectively quantify visual acuity in normal and amblyopic patients, and determine if it is possible to predict visual acuity in disability assessment to register visual pathway lesions. Methods A retrospective chart review was conducted of patients diagnosed with normal vision, unilateral amblyopia, optic neuritis, and visual disability who visited the university medical center for registration from March 2007 to October 2009. The study included 20 normal subjects (20 right eyes: 10 females, 10 males, ages 9–42 years, 18 unilateral amblyopic patients (18 amblyopic eyes, ages 19–36 years, 19 optic neuritis patients (19 eyes: ages 9–71 years, and 10 patients with visual disability having visual pathway lesions. Amplitude and latencies were analyzed and correlations with visual acuity (logMAR were derived from 20 normal and 18 amblyopic subjects. Correlation of VEP amplitude and visual acuity (logMAR of 19 optic neuritis patients confirmed relationships between visual acuity and amplitude. We calculated the objective visual acuity (logMAR of 16 eyes from 10 patients to diagnose the presence or absence of visual disability using relations derived from 20 normal and 18 amblyopic eyes. Results Linear regression analyses between amplitude of pattern visual evoked potentials and visual acuity (logMAR of 38 eyes from normal (right eyes and amblyopic (amblyopic eyes subjects were significant [y = −0.072x + 1.22, x: VEP amplitude, y: visual acuity (logMAR]. There were no significant differences between visual acuity prediction values, which substituted amplitude values of 19 eyes with optic neuritis into function. We calculated the objective visual acuity of 16 eyes of 10 patients to diagnose the presence or absence of visual disability using relations of y = −0.072x + 1.22 (−0.072. This resulted in a prediction

  3. Visual Sedimentation

    OpenAIRE

    Huron, Samuel; Vuillemot, Romain; Fekete, Jean-Daniel

    2013-01-01

    International audience; We introduce Visual Sedimentation, a novel design metaphor for visualizing data streams directly inspired by the physical process of sedimentation. Visualizing data streams (e. g., Tweets, RSS, Emails) is challenging as incoming data arrive at unpredictable rates and have to remain readable. For data streams, clearly expressing chronological order while avoiding clutter, and keeping aging data visible, are important. The metaphor is drawn from the real-world sedimentat...

  4. Visualization Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Evaluates and improves the operational effectiveness of existing and emerging electronic warfare systems. By analyzing and visualizing simulation results...

  5. A path reconstruction method integrating dead-reckoning and position fixes applied to humpback whales.

    Science.gov (United States)

    Wensveen, Paul J; Thomas, Len; Miller, Patrick J O

    2015-01-01

    Detailed information about animal location and movement is often crucial in studies of natural behaviour and how animals respond to anthropogenic activities. Dead-reckoning can be used to infer such detailed information, but without additional positional data this method results in uncertainty that grows with time. Combining dead-reckoning with new Fastloc-GPS technology should provide good opportunities for reconstructing georeferenced fine-scale tracks, and should be particularly useful for marine animals that spend most of their time under water. We developed a computationally efficient, Bayesian state-space modelling technique to estimate humpback whale locations through time, integrating dead-reckoning using on-animal sensors with measurements of whale locations using on-animal Fastloc-GPS and visual observations. Positional observation models were based upon error measurements made during calibrations. High-resolution 3-dimensional movement tracks were produced for 13 whales using a simple process model in which errors caused by water current movements, non-location sensor errors, and other dead-reckoning errors were accumulated into a combined error term. Positional uncertainty quantified by the track reconstruction model was much greater for tracks with visual positions and few or no GPS positions, indicating a strong benefit to using Fastloc-GPS for track reconstruction. Compared to tracks derived only from position fixes, the inclusion of dead-reckoning data greatly improved the level of detail in the reconstructed tracks of humpback whales. Using cross-validation, a clear improvement in the predictability of out-of-set Fastloc-GPS data was observed compared to more conventional track reconstruction methods. Fastloc-GPS observation errors during calibrations were found to vary by number of GPS satellites received and by orthogonal dimension analysed; visual observation errors varied most by distance to the whale. By systematically accounting for the

  6. Reoperative midface reconstruction.

    Science.gov (United States)

    Acero, Julio; García, Eloy

    2011-02-01

    Reoperative reconstruction of the midface is a challenging issue because of the complexity of this region and the severity of the aesthetic and functional sequela related to the absence or failure of a primary reconstruction. The different situations that can lead to the indication of a reoperative reconstructive procedure after previous oncologic ablative procedures in the midface are reviewed. Surgical techniques, anatomic problems, and limitations affecting the reoperative reconstruction in this region of the head and neck are discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. An iterative reduced field-of-view reconstruction for periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) MRI.

    Science.gov (United States)

    Lin, Jyh-Miin; Patterson, Andrew J; Chang, Hing-Chiu; Gillard, Jonathan H; Graves, Martin J

    2015-10-01

    To propose a new reduced field-of-view (rFOV) strategy for iterative reconstructions in a clinical environment. Iterative reconstructions can incorporate regularization terms to improve the image quality of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) MRI. However, the large amount of calculations required for full FOV iterative reconstructions has posed a huge computational challenge for clinical usage. By subdividing the entire problem into smaller rFOVs, the iterative reconstruction can be accelerated on a desktop with a single graphic processing unit (GPU). This rFOV strategy divides the iterative reconstruction into blocks, based on the block-diagonal dominant structure. A near real-time reconstruction system was developed for the clinical MR unit, and parallel computing was implemented using the object-oriented model. In addition, the Toeplitz method was implemented on the GPU to reduce the time required for full interpolation. Using the data acquired from the PROPELLER MRI, the reconstructed images were then saved in the digital imaging and communications in medicine format. The proposed rFOV reconstruction reduced the gridding time by 97%, as the total iteration time was 3 s even with multiple processes running. A phantom study showed that the structure similarity index for rFOV reconstruction was statistically superior to conventional density compensation (p reconstruction implemented. The rFOV strategy permits near real-time iterative reconstruction to improve the image quality of PROPELLER images. Substantial improvements in image quality metrics were validated in the experiments. The concept of rFOV reconstruction may potentially be applied to other kinds of iterative reconstructions for shortened reconstruction duration.

  8. Visual search

    NARCIS (Netherlands)

    Toet, A.; Bijl, P.

    2003-01-01

    Visual search, with or without the aid of optical or electro-optical instruments, plays a significant role in various types of military and civilian operations (e.g., reconnaissance, surveillance, and search and rescue). Advance knowledge of human visual search and target acquisition performance is

  9. [Breast reconstruction after mastectomy].

    Science.gov (United States)

    Ho Quoc, C; Delay, E

    2013-02-01

    The mutilating surgery for breast cancer causes deep somatic and psychological sequelae. Breast reconstruction can mitigate these effects and permit the patient to help rebuild their lives. The purpose of this paper is to focus on breast reconstruction techniques and on factors involved in breast reconstruction. The methods of breast reconstruction are presented: objectives, indications, different techniques, operative risks, and long-term monitoring. Many different techniques can now allow breast reconstruction in most patients. Clinical cases are also presented in order to understand the results we expect from a breast reconstruction. Breast reconstruction provides many benefits for patients in terms of rehabilitation, wellness, and quality of life. In our mind, breast reconstruction should be considered more as an opportunity and a positive choice (the patient can decide to do it), than as an obligation (that the patient would suffer). The consultation with the surgeon who will perform the reconstruction is an important step to give all necessary informations. It is really important that the patient could speak again with him before undergoing reconstruction, if she has any doubt. The quality of information given by medical doctors is essential to the success of psychological intervention. This article was written in a simple, and understandable way to help gynecologists giving the best information to their patients. It is maybe also possible to let them a copy of this article, which would enable them to have a written support and would facilitate future consultation with the surgeon who will perform the reconstruction. Copyright © 2012. Published by Elsevier Masson SAS.

  10. Visual Education

    DEFF Research Database (Denmark)

    Buhl, Mie; Flensborg, Ingelise

    2010-01-01

    The intrinsic breadth of various types of images creates new possibilities and challenges for visual education. The digital media have moved the boundaries between images and other kinds of modalities (e.g. writing, speech and sound) and have augmented the possibilities for integrating the functi......The intrinsic breadth of various types of images creates new possibilities and challenges for visual education. The digital media have moved the boundaries between images and other kinds of modalities (e.g. writing, speech and sound) and have augmented the possibilities for integrating...... to emerge in the interlocutory space of a global visual repertoire and diverse local interpretations. The two perspectives represent challenges for future visual education which require visual competences, not only within the arts but also within the subjects of natural sciences, social sciences, languages...

  11. A Visual-Aided Inertial Navigation and Mapping System

    Directory of Open Access Journals (Sweden)

    Rodrigo Munguía

    2016-05-01

    Full Text Available State estimation is a fundamental necessity for any application involving autonomous robots. This paper describes a visual-aided inertial navigation and mapping system for application to autonomous robots. The system, which relies on Kalman filtering, is designed to fuse the measurements obtained from a monocular camera, an inertial measurement unit (IMU and a position sensor (GPS. The estimated state consists of the full state of the vehicle: the position, orientation, their first derivatives and the parameter errors of the inertial sensors (i.e., the bias of gyroscopes and accelerometers. The system also provides the spatial locations of the visual features observed by the camera. The proposed scheme was designed by considering the limited resources commonly available in small mobile robots, while it is intended to be applied to cluttered environments in order to perform fully vision-based navigation in periods where the position sensor is not available. Moreover, the estimated map of visual features would be suitable for multiple tasks: i terrain analysis; ii three-dimensional (3D scene reconstruction; iii localization, detection or perception of obstacles and generating trajectories to navigate around these obstacles; and iv autonomous exploration. In this work, simulations and experiments with real data are presented in order to validate and demonstrate the performance of the proposal.

  12. Delayed breast implant reconstruction

    DEFF Research Database (Denmark)

    Hvilsom, Gitte B.; Hölmich, Lisbet R.; Steding-Jessen, Marianne

    2012-01-01

    We evaluated the association between radiation therapy and severe capsular contracture or reoperation after 717 delayed breast implant reconstruction procedures (288 1- and 429 2-stage procedures) identified in the prospective database of the Danish Registry for Plastic Surgery of the Breast during...... reconstruction approaches other than implants should be seriously considered among women who have received radiation therapy....

  13. A generic system dynamics model for simulating and evaluating the hydrological performance of reconstructed watersheds

    Directory of Open Access Journals (Sweden)

    N. Keshta

    2009-06-01

    Full Text Available A generic system dynamics watershed (GSDW model is developed and applied to five reconstructed watersheds located in the Athabasca mining basin, Alberta, Canada, and one natural watershed (boreal forest located in Saskatchewan, Canada, to simulate various hydrological processes in reconstructed and natural watersheds. This paper uses the root mean square error (RMSE, the mean absolute relative error (MARE, and the correlation coefficient (R as the main performance indicators, in addition to the visual comparison. For the South Bison Hills (SBH, South West Sand Storage (SWSS and Old Aspen (OA simulated soil moisture, the RMSE values ranges between 2.5–4.8 mm, and the MARE ranges from 7% to 18%, except for the D2-cover it was 26% for the validation year. The R statistics ranges from 0.3 to 0.77 during the validation period. The error between the measured and simulated cumulative actual evapotranspiration (AET flux for the SWSS, SBH, and the OA sites were 2%, 5%, and 8%, respectively. The developed GSDW model enables the investigation of the utility of different soil cover designs and evaluation of their performance. The model is capable of capturing the dynamics of water balance components, and may used to conduct short- and long- term predictions under different climate scenarios.

  14. Anatomical Individualized ACL Reconstruction

    Directory of Open Access Journals (Sweden)

    Amir Ata Rahnemai-Azar

    2016-10-01

    Full Text Available The anterior cruciate ligament (ACL is composed of two bundles, which work together to provide both antero-posterior and rotatory stability of the knee. Understanding the anatomy and function of the ACL plays a key role in management of patients with ACL injury. Anatomic ACL reconstruction aims to restore the function of the native ACL. Femoral and tibial tunnels should be placed in their anatomical location accounting for both the native ACL insertion site and bony landmarks. One main component of anatomical individualized ACL reconstruction is customizing the treatment according to each patient’s individual characteristics, considering preoperative and intraoperative evaluation of the native ACL and knee bony anatomy. Anatomical individualized reconstruction surgery should also aim to restore the size of the native ACL insertion as well. Using this concept, while single bundle ACL reconstruction can restore the function of the ACL in some patients, double bundle reconstruction is indicated in others to achieve optimal outcome.

  15. Prevalence of Body Dysmorphic Disorder Among Patients Seeking Breast Reconstruction.

    Science.gov (United States)

    Metcalfe, Drew B; Duggal, Claire S; Gabriel, Allen; Nahabedian, Maurice Y; Carlson, Grant W; Losken, Albert

    2014-07-01

    Body dysmorphic disorder (BDD) is characterized by a preoccupation with a slight or imagined defect in physical appearance. It has significant implications for patients who desire breast reconstruction, because patient satisfaction with the aesthetic outcome is a substantial contributor to the success of the procedure. The authors estimated the prevalence of BDD among women seeking breast reconstruction by surveying patients with the previously validated Dysmorphic Concerns Questionnaire (DCQ). One hundred eighty-eight women who presented for immediate or delayed breast reconstruction completed the DCQ anonymously, during initial consultation with a plastic surgeon. Two groups of respondents were identified: those who desired immediate reconstruction and those who planned to undergo delayed reconstruction. The prevalence of BDD among breast reconstruction patients was compared between the 2 groups, and the overall prevalence was compared with published rates for the general public. Body dysmorphic disorder was significantly more prevalent in breast reconstruction patients than in the general population (17% vs 2%; P < .001). It also was much more common among patients who planned to undergo delayed (vs immediate) reconstruction (34% vs 13%; P = .004). Relative to the general public, significantly more women who sought breast reconstruction were diagnosed as having BDD. Awareness of the potential for BDD will enable clinicians to better understand their patients' perspectives and discuss realistic expectations at the initial consultation. Future studies are warranted to examine the implications of BDD on patient satisfaction with reconstructive surgery. 3. © 2014 The American Society for Aesthetic Plastic Surgery, Inc.

  16. Visual cognition.

    Science.gov (United States)

    Cavanagh, Patrick

    2011-07-01

    Visual cognition, high-level vision, mid-level vision and top-down processing all refer to decision-based scene analyses that combine prior knowledge with retinal input to generate representations. The label "visual cognition" is little used at present, but research and experiments on mid- and high-level, inference-based vision have flourished, becoming in the 21st century a significant, if often understated part, of current vision research. How does visual cognition work? What are its moving parts? This paper reviews the origins and architecture of visual cognition and briefly describes some work in the areas of routines, attention, surfaces, objects, and events (motion, causality, and agency). Most vision scientists avoid being too explicit when presenting concepts about visual cognition, having learned that explicit models invite easy criticism. What we see in the literature is ample evidence for visual cognition, but few or only cautious attempts to detail how it might work. This is the great unfinished business of vision research: at some point we will be done with characterizing how the visual system measures the world and we will have to return to the question of how vision constructs models of objects, surfaces, scenes, and events. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Visual cognition

    OpenAIRE

    Cavanagh, Patrick

    2011-01-01

    Visual cognition, high-level vision, mid-level vision and top-down processing all refer to decision-based scene analyses that combine prior knowledge with retinal input to generate representations. The label “visual cognition” is little used at present, but research and experiments on mid- and high-level, inference-based vision have flourished, becoming in the 21st century a significant, if often understated part, of current vision research. How does visual cognition work? What are its moving...

  18. Learning Science Through Visualization

    Science.gov (United States)

    Chaudhury, S. Raj

    2005-01-01

    In the context of an introductory physical science course for non-science majors, I have been trying to understand how scientific visualizations of natural phenomena can constructively impact student learning. I have also necessarily been concerned with the instructional and assessment approaches that need to be considered when focusing on learning science through visually rich information sources. The overall project can be broken down into three distinct segments : (i) comparing students' abilities to demonstrate proportional reasoning competency on visual and verbal tasks (ii) decoding and deconstructing visualizations of an object falling under gravity (iii) the role of directed instruction to elicit alternate, valid scientific visualizations of the structure of the solar system. Evidence of student learning was collected in multiple forms for this project - quantitative analysis of student performance on written, graded assessments (tests and quizzes); qualitative analysis of videos of student 'think aloud' sessions. The results indicate that there are significant barriers for non-science majors to succeed in mastering the content of science courses, but with informed approaches to instruction and assessment, these barriers can be overcome.

  19. Luminosity Spectrum Reconstruction at Linear Colliders

    CERN Document Server

    Poss, Stéphane

    2014-04-11

    A good knowledge of the luminosity spectrum is mandatory for many measurements at future e+e- colliders. As the beam-parameters determining the luminosity spectrum cannot be measured precisely, the luminosity spectrum has to be measured through a gauge process with the detector. The measured distributions, used to reconstruct the spectrum, depend on Initial State Radiation, cross-section, and Final State Radiation. To extract the basic luminosity spectrum, a parametric model of the luminosity spectrum is created, in this case the spectrum at the 3 TeV Compact Linear Collider (CLIC). The model is used within a reweighting technique to extract the luminosity spectrum from measured Bhabha event observables, taking all relevant effects into account. The centre-of-mass energy spectrum is reconstructed within 5% over the full validity range of the model. The reconstructed spectrum does not result in a significant bias or systematic uncertainty in the exemplary physics benchmark process of smuon pair production.

  20. Fourier ptychographic reconstruction using Wirtinger flow optimization

    CERN Document Server

    Bian, Liheng; Zheng, Guoan; Guo, KaiKai; Chen, Feng; Dai, Qionghai

    2014-01-01

    Recently Fourier Ptychography (FP) has attracted great attention, due to its marked effectiveness in leveraging snapshot numbers for spatial resolution in large field-of-view imaging. To acquire high signal-to-noise-ratio (SNR) images under angularly varying illuminations for subsequent reconstruction, FP requires long exposure time, which largely limits its practical applications. In this paper, based on the recently reported Wirtinger flow algorithm, we propose an iterative optimization framework incorporating phase retrieval and noise relaxation together, to realize FP reconstruction using low SNR images captured under short exposure time. Experiments on both synthetic and real captured data validate the effectiveness of the proposed reconstruction method. Specifically, the proposed technique could save around 80% exposure time to achieve similar retrieval accuracy compared to the conventional FP. Besides, we have released our source code for non-commercial use.

  1. Memorizing and Copying Visual Patterns: A Piagetian Interpretation.

    Science.gov (United States)

    Chap, Janet Blum; Ross, Bruce M.

    1979-01-01

    In order to determine whether mistakes committed by younger children are the result of retention mistakes rather than faulty perceptual encoding, twenty children (6, 8, 10, and 12 years old) reconstructed two visual patterns from immediate memory, while twenty other children (5 and 6 years old) reconstructed the identical patterns by direct…

  2. Autofluorescence imaging for improved visualization of joint structures during arthroscopic surgery.

    Science.gov (United States)

    Nguyen, Duy Tan; van Horssen, Pepijn; Derriks, Hans; van de Giessen, Martijn; van Leeuwen, Ton

    2017-12-01

    The purpose of our study is to develop the arthroscopic autofluorescence imaging (AFI) system to improve the visualization during arthroscopic surgery by real-time enhancing the contrast between joint structures with autofluorescence imaging. Its validity was evaluated around the arthroscopic anterior cruciate ligament (ACL) reconstruction, specifically improving the contrast between the femoral insertion site and its background. The feasibility of the AFI system was validated with bovine and human knees. The spectral responses of the femoral insertion site and its surrounding bone and cartilage were measured with a fluorospectrometer. A prototype of the AFI system was developed based on the spectral responses (SR) and test images of the insertion site. The accuracy was validated by evaluating the overlap between manually segmented insertion sites on the white light color images and on the corresponding spectral unmixed autofluorescence images. The final prototype of the AFI system was tested during arthroscopy in cadaveric knees. The results showed that the joint structures have different SRs. Spectral unmixing enabled separation of the SRs and improved the contrast between the joint structures. The agreement between visible light and autofluorescence ligament insertions had a mean Dice coefficient of 0.84 and the mean Dice coefficient of the interobserver variability for visible light imaging was 0.85. We have shown that the femoral insertion site can be accurately visualized with autofluorescence imaging combined with spectral unmixing. The AFI system demonstrates the feasibility of real-time and subject-specific visualization of the femoral insertion site which can facilitate anatomic ACL reconstruction. In addition, the AFI system can facilitate arthroscopic procedures in other joints and can also be used as a diagnostic tool.

  3. Visual Confidence.

    Science.gov (United States)

    Mamassian, Pascal

    2016-10-14

    Visual confidence refers to an observer's ability to judge the accuracy of her perceptual decisions. Even though confidence judgments have been recorded since the early days of psychophysics, only recently have they been recognized as essential for a deeper understanding of visual perception. The reluctance to study visual confidence may have come in part from obtaining convincing experimental evidence in favor of metacognitive abilities rather than just perceptual sensitivity. Some effort has thus been dedicated to offer different experimental paradigms to study visual confidence in humans and nonhuman animals. To understand the origins of confidence judgments, investigators have developed two competing frameworks. The approach based on signal decision theory is popular but fails to account for response times. In contrast, the approach based on accumulation of evidence models naturally includes the dynamics of perceptual decisions. These models can explain a range of results, including the apparently paradoxical dissociation between performance and confidence that is sometimes observed.

  4. Visual cognition

    Energy Technology Data Exchange (ETDEWEB)

    Pinker, S.

    1985-01-01

    This book consists of essays covering issues in visual cognition presenting experimental techniques from cognitive psychology, methods of modeling cognitive processes on computers from artificial intelligence, and methods of studying brain organization from neuropsychology. Topics considered include: parts of recognition; visual routines; upward direction; mental rotation, and discrimination of left and right turns in maps; individual differences in mental imagery, computational analysis and the neurological basis of mental imagery: componental analysis.

  5. Hybrid spectral CT reconstruction

    Science.gov (United States)

    Clark, Darin P.

    2017-01-01

    Current photon counting x-ray detector (PCD) technology faces limitations associated with spectral fidelity and photon starvation. One strategy for addressing these limitations is to supplement PCD data with high-resolution, low-noise data acquired with an energy-integrating detector (EID). In this work, we propose an iterative, hybrid reconstruction technique which combines the spectral properties of PCD data with the resolution and signal-to-noise characteristics of EID data. Our hybrid reconstruction technique is based on an algebraic model of data fidelity which substitutes the EID data into the data fidelity term associated with the PCD reconstruction, resulting in a joint reconstruction problem. Within the split Bregman framework, these data fidelity constraints are minimized subject to additional constraints on spectral rank and on joint intensity-gradient sparsity measured between the reconstructions of the EID and PCD data. Following a derivation of the proposed technique, we apply it to the reconstruction of a digital phantom which contains realistic concentrations of iodine, barium, and calcium encountered in small-animal micro-CT. The results of this experiment suggest reliable separation and detection of iodine at concentrations ≥ 5 mg/ml and barium at concentrations ≥ 10 mg/ml in 2-mm features for EID and PCD data reconstructed with inherent spatial resolutions of 176 μm and 254 μm, respectively (point spread function, FWHM). Furthermore, hybrid reconstruction is demonstrated to enhance spatial resolution within material decomposition results and to improve low-contrast detectability by as much as 2.6 times relative to reconstruction with PCD data only. The parameters of the simulation experiment are based on an in vivo micro-CT experiment conducted in a mouse model of soft-tissue sarcoma. Material decomposition results produced from this in vivo data demonstrate the feasibility of distinguishing two K-edge contrast agents with a spectral

  6. Hybrid spectral CT reconstruction.

    Directory of Open Access Journals (Sweden)

    Darin P Clark

    Full Text Available Current photon counting x-ray detector (PCD technology faces limitations associated with spectral fidelity and photon starvation. One strategy for addressing these limitations is to supplement PCD data with high-resolution, low-noise data acquired with an energy-integrating detector (EID. In this work, we propose an iterative, hybrid reconstruction technique which combines the spectral properties of PCD data with the resolution and signal-to-noise characteristics of EID data. Our hybrid reconstruction technique is based on an algebraic model of data fidelity which substitutes the EID data into the data fidelity term associated with the PCD reconstruction, resulting in a joint reconstruction problem. Within the split Bregman framework, these data fidelity constraints are minimized subject to additional constraints on spectral rank and on joint intensity-gradient sparsity measured between the reconstructions of the EID and PCD data. Following a derivation of the proposed technique, we apply it to the reconstruction of a digital phantom which contains realistic concentrations of iodine, barium, and calcium encountered in small-animal micro-CT. The results of this experiment suggest reliable separation and detection of iodine at concentrations ≥ 5 mg/ml and barium at concentrations ≥ 10 mg/ml in 2-mm features for EID and PCD data reconstructed with inherent spatial resolutions of 176 μm and 254 μm, respectively (point spread function, FWHM. Furthermore, hybrid reconstruction is demonstrated to enhance spatial resolution within material decomposition results and to improve low-contrast detectability by as much as 2.6 times relative to reconstruction with PCD data only. The parameters of the simulation experiment are based on an in vivo micro-CT experiment conducted in a mouse model of soft-tissue sarcoma. Material decomposition results produced from this in vivo data demonstrate the feasibility of distinguishing two K-edge contrast agents with

  7. Hybrid spectral CT reconstruction.

    Science.gov (United States)

    Clark, Darin P; Badea, Cristian T

    2017-01-01

    Current photon counting x-ray detector (PCD) technology faces limitations associated with spectral fidelity and photon starvation. One strategy for addressing these limitations is to supplement PCD data with high-resolution, low-noise data acquired with an energy-integrating detector (EID). In this work, we propose an iterative, hybrid reconstruction technique which combines the spectral properties of PCD data with the resolution and signal-to-noise characteristics of EID data. Our hybrid reconstruction technique is based on an algebraic model of data fidelity which substitutes the EID data into the data fidelity term associated with the PCD reconstruction, resulting in a joint reconstruction problem. Within the split Bregman framework, these data fidelity constraints are minimized subject to additional constraints on spectral rank and on joint intensity-gradient sparsity measured between the reconstructions of the EID and PCD data. Following a derivation of the proposed technique, we apply it to the reconstruction of a digital phantom which contains realistic concentrations of iodine, barium, and calcium encountered in small-animal micro-CT. The results of this experiment suggest reliable separation and detection of iodine at concentrations ≥ 5 mg/ml and barium at concentrations ≥ 10 mg/ml in 2-mm features for EID and PCD data reconstructed with inherent spatial resolutions of 176 μm and 254 μm, respectively (point spread function, FWHM). Furthermore, hybrid reconstruction is demonstrated to enhance spatial resolution within material decomposition results and to improve low-contrast detectability by as much as 2.6 times relative to reconstruction with PCD data only. The parameters of the simulation experiment are based on an in vivo micro-CT experiment conducted in a mouse model of soft-tissue sarcoma. Material decomposition results produced from this in vivo data demonstrate the feasibility of distinguishing two K-edge contrast agents with a spectral

  8. Confiabilidade e validade de um dinamômetro isométrico modificado na avaliação do desempenho muscular em indivíduos com reconstrução do ligamento cruzado anterior Reliability and validity of a modified isometric dynamometer in the assessment of muscular performance in individuals with anterior cruciate ligament reconstruction

    Directory of Open Access Journals (Sweden)

    Rodrigo Antunes de Vasconcelos

    2009-06-01

    Full Text Available OBJETIVO: Analisar a confiabilidade e validade de um dinamômetro isométrico modificado (DIM na avaliação dos déficits no desempenho muscular dos extensores e flexores do joelho em indivíduos normais e com reconstrução do LCA. MÉTODOS: Foram convidados 60 voluntários do sexo masculino a participar do estudo, divididos em três grupos de 20 indivíduos: grupo controle (GC, grupo com reconstrução do LCA com tendão patelar (GTP e grupo com reconstrução do LCA com tendões flexores (GTF. Todos os indivíduos realizaram teste isométrico dos extensores e flexores do joelho no DIM; os déficits de força muscular coletados foram comparados posteriormente com os testes realizados no Biodex System 3 operando no modo isométrico e isocinético nas velocidades de 60º/s e 180º /s. Foram realizados cálculos de correlação intraclasse ICC para avaliar a confiabilidade do DIM, cálculos da especificidade, sensibilidade e coeficiente de concordância Kappa, respectivamente, para avaliar a validade do DIM em detectar déficits musculares e comparações intragrupos e intergrupos na realização dos quatro testes de força utilizando-se do método ANOVA. RESULTADOS: O DIM demonstrou excelente confiabilidade teste-reteste e validade na avaliação do desempenho muscular dos extensores e flexores do joelho. Na comparação intergrupos. o GTP demonstrou déficits significativamente maiores dos extensores comparados com os grupos GC e GTF. CONCLUSÃO: Dinamômetros isométricos conectados em equipamentos de mecanoterapia podem ser uma alternativa para coletar dados referentes a déficits no desempenho muscular dos extensores e flexores do joelho em indivíduos com reconstrução do LCA.OBJECTIVES: The aim of this study was to evaluate the reliability and validity of a modified isometric dynamometer (MID in performance deficits of the knee extensor and flexor muscles in normal individuals and in those with ACL reconstructions. METHODS: Sixty male

  9. An Anatomically Validated Brachial Plexus Contouring Method for Intensity Modulated Radiation Therapy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Van de Velde, Joris, E-mail: joris.vandevelde@ugent.be [Department of Anatomy, Ghent University, Ghent (Belgium); Department of Radiotherapy, Ghent University, Ghent (Belgium); Audenaert, Emmanuel [Department of Physical Medicine and Orthopedic Surgery, Ghent University, Ghent (Belgium); Speleers, Bruno; Vercauteren, Tom; Mulliez, Thomas [Department of Radiotherapy, Ghent University, Ghent (Belgium); Vandemaele, Pieter; Achten, Eric [Department of Radiology, Ghent University, Ghent (Belgium); Kerckaert, Ingrid; D' Herde, Katharina [Department of Anatomy, Ghent University, Ghent (Belgium); De Neve, Wilfried [Department of Radiotherapy, Ghent University, Ghent (Belgium); Van Hoof, Tom [Department of Anatomy, Ghent University, Ghent (Belgium)

    2013-11-15

    Purpose: To develop contouring guidelines for the brachial plexus (BP) using anatomically validated cadaver datasets. Magnetic resonance imaging (MRI) and computed tomography (CT) were used to obtain detailed visualizations of the BP region, with the goal of achieving maximal inclusion of the actual BP in a small contoured volume while also accommodating for anatomic variations. Methods and Materials: CT and MRI were obtained for 8 cadavers positioned for intensity modulated radiation therapy. 3-dimensional reconstructions of soft tissue (from MRI) and bone (from CT) were combined to create 8 separate enhanced CT project files. Dissection of the corresponding cadavers anatomically validated the reconstructions created. Seven enhanced CT project files were then automatically fitted, separately in different regions, to obtain a single dataset of superimposed BP regions that incorporated anatomic variations. From this dataset, improved BP contouring guidelines were developed. These guidelines were then applied to the 7 original CT project files and also to 1 additional file, left out from the superimposing procedure. The percentage of BP inclusion was compared with the published guidelines. Results: The anatomic validation procedure showed a high level of conformity for the BP regions examined between the 3-dimensional reconstructions generated and the dissected counterparts. Accurate and detailed BP contouring guidelines were developed, which provided corresponding guidance for each level in a clinical dataset. An average margin of 4.7 mm around the anatomically validated BP contour is sufficient to accommodate for anatomic variations. Using the new guidelines, 100% inclusion of the BP was achieved, compared with a mean inclusion of 37.75% when published guidelines were applied. Conclusion: Improved guidelines for BP delineation were developed using combined MRI and CT imaging with validation by anatomic dissection.

  10. Head and Neck Reconstruction.

    Science.gov (United States)

    Wong, Shannon; Melin, Alyson; Reilly, Debra

    2017-10-01

    Management of head and neck burns involves acute and intermediate phases. Acutely, the goals are establish a secure airway and treat life-threatening injuries. Then, optimize nutrition, assess extent of the burn, perform local wound care, and provide eye protection. Management depends on the degree of the head and neck burn. Postinjury splinting and rehabilitation are vital to healing. After the acute inflammation has resolved and the scars have matured, reconstruction begins with the goals of restoring both function and aesthetics. Reconstruction ranges from simple scar release, to skin grafting, and possibly free flap reconstruction. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Iterative reconstruction of volumetric particle distribution

    Science.gov (United States)

    Wieneke, Bernhard

    2013-02-01

    For tracking the motion of illuminated particles in space and time several volumetric flow measurement techniques are available like 3D-particle tracking velocimetry (3D-PTV) recording images from typically three to four viewing directions. For higher seeding densities and the same experimental setup, tomographic PIV (Tomo-PIV) reconstructs voxel intensities using an iterative tomographic reconstruction algorithm (e.g. multiplicative algebraic reconstruction technique, MART) followed by cross-correlation of sub-volumes computing instantaneous 3D flow fields on a regular grid. A novel hybrid algorithm is proposed here that similar to MART iteratively reconstructs 3D-particle locations by comparing the recorded images with the projections calculated from the particle distribution in the volume. But like 3D-PTV, particles are represented by 3D-positions instead of voxel-based intensity blobs as in MART. Detailed knowledge of the optical transfer function and the particle image shape is mandatory, which may differ for different positions in the volume and for each camera. Using synthetic data it is shown that this method is capable of reconstructing densely seeded flows up to about 0.05 ppp with similar accuracy as Tomo-PIV. Finally the method is validated with experimental data.

  12. Visualizing water

    Science.gov (United States)

    Baart, F.; van Gils, A.; Hagenaars, G.; Donchyts, G.; Eisemann, E.; van Velzen, J. W.

    2016-12-01

    A compelling visualization is captivating, beautiful and narrative. Here we show how melding the skills of computer graphics, art, statistics, and environmental modeling can be used to generate innovative, attractive and very informative visualizations. We focus on the topic of visualizing forecasts and measurements of water (water level, waves, currents, density, and salinity). For the field of computer graphics and arts, water is an important topic because it occurs in many natural scenes. For environmental modeling and statistics, water is an important topic because the water is essential for transport, a healthy environment, fruitful agriculture, and a safe environment.The different disciplines take different approaches to visualizing water. In computer graphics, one focusses on creating water as realistic looking as possible. The focus on realistic perception (versus the focus on the physical balance pursued by environmental scientists) resulted in fascinating renderings, as seen in recent games and movies. Visualization techniques for statistical results have benefited from the advancement in design and journalism, resulting in enthralling infographics. The field of environmental modeling has absorbed advances in contemporary cartography as seen in the latest interactive data-driven maps. We systematically review the design emerging types of water visualizations. The examples that we analyze range from dynamically animated forecasts, interactive paintings, infographics, modern cartography to web-based photorealistic rendering. By characterizing the intended audience, the design choices, the scales (e.g. time, space), and the explorability we provide a set of guidelines and genres. The unique contributions of the different fields show how the innovations in the current state of the art of water visualization have benefited from inter-disciplinary collaborations.

  13. A technique system for the measurement, reconstruction and character extraction of rice plant architecture.

    Directory of Open Access Journals (Sweden)

    Xumeng Li

    Full Text Available This study developed a technique system for the measurement, reconstruction, and trait extraction of rice canopy architectures, which have challenged functional-structural plant modeling for decades and have become the foundation of the design of ideo-plant architectures. The system uses the location-separation-measurement method (LSMM for the collection of data on the canopy architecture and the analytic geometry method for the reconstruction and visualization of the three-dimensional (3D digital architecture of the rice plant. It also uses the virtual clipping method for extracting the key traits of the canopy architecture such as the leaf area, inclination, and azimuth distribution in spatial coordinates. To establish the technique system, we developed (i simple tools to measure the spatial position of the stem axis and azimuth of the leaf midrib and to capture images of tillers and leaves; (ii computer software programs for extracting data on stem diameter, leaf nodes, and leaf midrib curves from the tiller images and data on leaf length, width, and shape from the leaf images; (iii a database of digital architectures that stores the measured data and facilitates the reconstruction of the 3D visual architecture and the extraction of architectural traits; and (iv computation algorithms for virtual clipping to stratify the rice canopy, to extend the stratified surface from the horizontal plane to a general curved surface (including a cylindrical surface, and to implement in silico. Each component of the technique system was quantitatively validated and visually compared to images, and the sensitivity of the virtual clipping algorithms was analyzed. This technique is inexpensive and accurate and provides high throughput for the measurement, reconstruction, and trait extraction of rice canopy architectures. The technique provides a more practical method of data collection to serve functional-structural plant models of rice and for the

  14. Forging Provincial Reconstruction Teams

    National Research Council Canada - National Science Library

    Honore, Russel L; Boslego, David V

    2007-01-01

    The Provincial Reconstruction Team (PRT) training mission completed by First U.S. Army in April 2006 was a joint Service effort to meet a requirement from the combatant commander to support goals in Afghanistan...

  15. Reconstructions of eyelid defects

    Directory of Open Access Journals (Sweden)

    Nirmala Subramanian

    2011-01-01

    Full Text Available Eyelids are the protective mechanism of the eyes. The upper and lower eyelids have been formed for their specific functions by Nature. The eyelid defects are encountered in congenital anomalies, trauma, and postexcision for neoplasm. The reconstructions should be based on both functional and cosmetic aspects. The knowledge of the basic anatomy of the lids is a must. There are different techniques for reconstructing the upper eyelid, lower eyelid, and medial and lateral canthal areas. Many a times, the defects involve more than one area. For the reconstruction of the lid, the lining should be similar to the conjunctiva, a cover by skin and the middle layer to give firmness and support. It is important to understand the availability of various tissues for reconstruction. One layer should have the vascularity to support the other layer which can be a graft. A proper plan and execution of it is very important.

  16. Tessellation reconstruction techniques

    NARCIS (Netherlands)

    de Weygaert, RV; Schaap, W; Banday, AJ; Zaroubi, S; Bartelmann, M

    2001-01-01

    The application of Voronoi and Delaunay tessellation based methods for reconstructing continuous fields from discretely sampled data sets is discussed. The succesfull operation as "multidimensional interpolation" method is corroborated through their ability to reproduce even intricate statistical

  17. Prairie Reconstruction Initiative Project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of the Prairie Reconstruction Initiative Advisory Team (PRIAT) is to identify and take steps to resolve uncertainties in the process of prairie...

  18. Joint reconstruction of simultaneously acquired MR-PET data with multi sensor compressed sensing based on a joint sparsity constraint

    Energy Technology Data Exchange (ETDEWEB)

    Knoll, Florian; Koesters, Thomas; Otazo, Ricardo; Block, Tobias; Feng, Li [Bernard & Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU School of Medicine, New York, New York (United States); Vunckx, Kathleen [Department of Nuclear Medicine, KU Leuven, Leuven (Belgium); Faul, David [Siemens Medical Solutions USA, New York (United States); Nuyts, Johan [Department of Nuclear Medicine, KU Leuven, Leuven (Belgium); Boada, Fernando; Sodickson, Daniel K [Bernard & Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU School of Medicine, New York, New York (United States)

    2014-07-29

    State-of-the-art MR-PET scanners allow simultaneous data acquisition. However, image reconstruction is performed separately and results are only combined at the visualization stage. PET images are reconstructed using a variant of EM and MR data are reconstructed using an inverse Fourier transform or iterative algorithms for parallel imaging or compressed sensing. We propose a new iterative joint reconstruction framework based on multi-sensor compressed sensing that exploits anatomical correlations between MR and PET.

  19. Inverse imbalance reconstruction in rotordynamics

    Energy Technology Data Exchange (ETDEWEB)

    Ramlau, R. [Austrian Academy of Sciences, Linz (Austria). Johann Radon Inst. for Computational and Applied Mathematics; Dicken, V. [MeVis GmbH, Bremen (Germany); Maass, P. [Bremen Univ. (Germany). Zentrum fuer Technomathematik; Streller, C. [Rolls-Royce Germany GmbH, Dahlewitz (Germany); Rienaecker, A. [MTU Aero Engines GmbH, Muenchen (Germany)

    2006-05-15

    The goal of this work is to establish and compare algorithms for inverse imbalance reconstruction in aircraft turbines. Such algorithms are based on a validated whole engine model of a turbo engine under consideration. Base on the model, the impact of an imbalance distribution on the vibration behaviour of the turbine can be described as a matrix-vector multiplication Af = g, where f is the imbalance distribution and g the vibration response. It turns out that the matrix A is very ill-conditioned. As the measured data is highly affected with noise, we have to use regularization methods in order to stabilize the inversion. Our main interest was in the use of nonlinear regularization methods, in particular nonlinear filtered singular value decomposition and conjugate gradient regularization. (orig.)

  20. 3D heart reconstruction

    OpenAIRE

    Roxo, Diogo

    2011-01-01

    The purpose of this thesis was to achieve a 3D reconstruction of the four heart chambers using 2D echocardiographic images. A level set algorithm based on the phase symmetry approach and on a new logarithmic based stopping function was used to extract simultaneously the four heart cavities from these images in a fully automatic way. However to proceed to the 3D reconstruction using the segmented images, it was first necessary to satisfy clinical practise requirements. This means that the algo...

  1. Visual stability.

    Science.gov (United States)

    Melcher, David

    2011-02-27

    Our vision remains stable even though the movements of our eyes, head and bodies create a motion pattern on the retina. One of the most important, yet basic, feats of the visual system is to correctly determine whether this retinal motion is owing to real movement in the world or rather our own self-movement. This problem has occupied many great thinkers, such as Descartes and Helmholtz, at least since the time of Alhazen. This theme issue brings together leading researchers from animal neurophysiology, clinical neurology, psychophysics and cognitive neuroscience to summarize the state of the art in the study of visual stability. Recently, there has been significant progress in understanding the limits of visual stability in humans and in identifying many of the brain circuits involved in maintaining a stable percept of the world. Clinical studies and new experimental methods, such as transcranial magnetic stimulation, now make it possible to test the causal role of different brain regions in creating visual stability and also allow us to measure the consequences when the mechanisms of visual stability break down.

  2. Interior reconstruction method based on rotation-translation scanning model.

    Science.gov (United States)

    Wang, Xianchao; Tang, Ziyue; Yan, Bin; Li, Lei; Bao, Shanglian

    2014-01-01

    In various applications of computed tomography (CT), it is common that the reconstructed object is over the field of view (FOV) or we may intend to sue a FOV which only covers the region of interest (ROI) for the sake of reducing radiation dose. These kinds of imaging situations often lead to interior reconstruction problems which are difficult cases in the reconstruction field of CT, due to the truncated projection data at every view angle. In this paper, an interior reconstruction method is developed based on a rotation-translation (RT) scanning model. The method is implemented by first scanning the reconstructed region, and then scanning a small region outside the support of the reconstructed object after translating the rotation centre. The differentiated backprojection (DBP) images of the reconstruction region and the small region outside the object can be respectively obtained from the two-time scanning data without data rebinning process. At last, the projection onto convex sets (POCS) algorithm is applied to reconstruct the interior region. Numerical simulations are conducted to validate the proposed reconstruction method.

  3. Visual cognition

    Energy Technology Data Exchange (ETDEWEB)

    Pinker, S.

    1985-01-01

    This collection of research papers on visual cognition first appeared as a special issue of Cognition: International Journal of Cognitive Science. The study of visual cognition has seen enormous progress in the past decade, bringing important advances in our understanding of shape perception, visual imagery, and mental maps. Many of these discoveries are the result of converging investigations in different areas, such as cognitive and perceptual psychology, artificial intelligence, and neuropsychology. This volume is intended to highlight a sample of work at the cutting edge of this research area for the benefit of students and researchers in a variety of disciplines. The tutorial introduction that begins the volume is designed to help the nonspecialist reader bridge the gap between the contemporary research reported here and earlier textbook introductions or literature reviews.

  4. HLT Validation of Athena

    CERN Document Server

    Bee, C P; González, S; Karr, K M; Wiedenmann, W

    2002-01-01

    In the present view, the ATLAS High Level Trigger will base its event selection software on the offline reconstruction framework, Athena. It is therefore imperative that the offline software -- and its relevant components -- are able to handle the large CPU and bandwidth loads required in a real-time environment. This note presents a first set of measurements aimed at validating Athena as the ATLAS online event selection framework. Although Athena is at an early development stage, detailed profiling can already yield clues as to which components can be optimized. In this note such areas are identified and a proposal is made on a road map to full performance.

  5. Coracoclavicular Ligament Reconstruction

    Science.gov (United States)

    Li, Qi; Hsueh, Pei-ling; Chen, Yun-feng

    2014-01-01

    Abstract Operative intervention is recommended for complete acromioclavicular (AC) joint dislocation to restore AC stability, but the best operative technique is still controversial. Twelve fresh-frozen male cadaveric shoulders (average age, 62.8 ± 7.8 years) were equally divided into endobutton versus the modified Weaver-Dunn groups. Each potted scapula and clavicle was fixed in a custom made jig to allow translation and load to failure testing using a Zwick BZ2.5/TS1S material testing machine (Zwick/Roell Co, Germany). A systematic review of 21 studies evaluating reconstructive methods for coracoclavicular or AC joints using a cadaveric model was also performed. From our biomechanical study, after ligament reconstruction, the triple endobutton technique demonstrated superior, anterior, and posterior displacements similar to that of the intact state (P > 0.05). In the modified Weaver-Dunn reconstruction group, however, there was significantly greater anterior (P ligament reconstruction. In addition, there was no significant difference after reconstruction between failure load of the triple endobutton group and that of the intact state (686.88 vs 684.9 N, P > 0.05), whereas the failure load after the modified Weaver-Dunn reconstruction was decreased compared with the intact state (171.64 vs 640.86 N, P ligament is superior to the modified Weaver-Dunn reconstruction in controlling both superior and anteroposterior displacements with a failure load that approximates the intact ligament. PMID:25526435

  6. Population Dynamics of Early Visual Cortex during Working Memory.

    Science.gov (United States)

    Rahmati, Masih; Saber, Golbarg T; Curtis, Clayton E

    2018-02-01

    Although the content of working memory (WM) can be decoded from the spatial patterns of brain activity in early visual cortex, how populations encode WM representations remains unclear. Here, we address this limitation by using a model-based approach that reconstructs the feature encoded by population activity measured with fMRI. Using this approach, we could successfully reconstruct the locations of memory-guided saccade goals based on the pattern of activity in visual cortex during a memory delay. We could reconstruct the saccade goal even when we dissociated the visual stimulus from the saccade goal using a memory-guided antisaccade procedure. By comparing the spatiotemporal population dynamics, we find that the representations in visual cortex are stable but can also evolve from a representation of a remembered visual stimulus to a prospective goal. Moreover, because the representation of the antisaccade goal cannot be the result of bottom-up visual stimulation, it must be evoked by top-down signals presumably originating from frontal and/or parietal cortex. Indeed, we find that trial-by-trial fluctuations in delay period activity in frontal and parietal cortex correlate with the precision with which our model reconstructed the maintained saccade goal based on the pattern of activity in visual cortex. Therefore, the population dynamics in visual cortex encode WM representations, and these representations can be sculpted by top-down signals from frontal and parietal cortex.

  7. Light field reconstruction robust to signal dependent noise

    Science.gov (United States)

    Ren, Kun; Bian, Liheng; Suo, Jinli; Dai, Qionghai

    2014-11-01

    Capturing four dimensional light field data sequentially using a coded aperture camera is an effective approach but suffers from low signal noise ratio. Although multiplexing can help raise the acquisition quality, noise is still a big issue especially for fast acquisition. To address this problem, this paper proposes a noise robust light field reconstruction method. Firstly, scene dependent noise model is studied and incorporated into the light field reconstruction framework. Then, we derive an optimization algorithm for the final reconstruction. We build a prototype by hacking an off-the-shelf camera for data capturing and prove the concept. The effectiveness of this method is validated with experiments on the real captured data.

  8. THE APPLICATION OF 3D PRINTING IN PLASTIC AND RECONSTRUCTIVE SURGERY: CASE-CONTROL STUDY IN FACIAL RECONSTRUCTION

    Directory of Open Access Journals (Sweden)

    Luigi Di Rosa

    2017-10-01

    Full Text Available The aim of this study was to explore the efficiency and usefulness of tridimensional printing in plastic and reconstructive surgery for lesions of the maxillofacial region. This was comparison study between two groups of patients. Six patients underwent surgical reconstruction, using a three-dimensional model built on the basis of CT scans (group 1; and six patients underwent surgical reconstruction, without the use of a three-dimensional model (group 2. The following variables were evaluated: age, gender, histological diagnosis, cancer location, size of bone lesion, type of reconstruction, complications and surgical timing. A statistically significant difference was found in microsurgical flap survival (p = 0.019, with a survival rate higher in group 1 than in the controls. This study provides preliminary evidence and partially confirms the validity of three-dimensional technology in plastic and reconstructive surgery. The results so far obtained, however, lead to hope for future uses of this ever-increasing technique.

  9. Traffic Visualization

    DEFF Research Database (Denmark)

    Picozzi, Matteo; Verdezoto, Nervo; Pouke, Matti

    2013-01-01

    techniques to give a rapid overview of traffic data. We illustrate our approach as a case study for traffic visualization systems, using datasets from the city of Oulu that can be extended to other city planning activities. We also report the feedback of real users (traffic management employees, traffic police...

  10. Visualizing inequality

    Science.gov (United States)

    Eliazar, Iddo

    2016-07-01

    The study of socioeconomic inequality is of substantial importance, scientific and general alike. The graphic visualization of inequality is commonly conveyed by Lorenz curves. While Lorenz curves are a highly effective statistical tool for quantifying the distribution of wealth in human societies, they are less effective a tool for the visual depiction of socioeconomic inequality. This paper introduces an alternative to Lorenz curves-the hill curves. On the one hand, the hill curves are a potent scientific tool: they provide detailed scans of the rich-poor gaps in human societies under consideration, and are capable of accommodating infinitely many degrees of freedom. On the other hand, the hill curves are a powerful infographic tool: they visualize inequality in a most vivid and tangible way, with no quantitative skills that are required in order to grasp the visualization. The application of hill curves extends far beyond socioeconomic inequality. Indeed, the hill curves are highly effective 'hyperspectral' measures of statistical variability that are applicable in the context of size distributions at large. This paper establishes the notion of hill curves, analyzes them, and describes their application in the context of general size distributions.

  11. Reconstruction of Intensity From Covered Samples

    Energy Technology Data Exchange (ETDEWEB)

    Barabash, Rozaliya [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Watkins, Thomas R [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Meisner, Roberta Ann [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burchell, Timothy D [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rosseel, Thomas M [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    The safe handling of activated samples requires containment and covering the sample to eliminate any potential for contamination. Subsequent characterization of the surface with x-rays ideally necessitates a thin film. While many films appear visually transparent, they are not necessarily x-ray transparent. Each film material has a unique beam attenuation and sometimes have amorphous peaks that can superimpose with those of the sample. To reconstruct the intensity of the underlying activated sample, the x-ray attenuation and signal due to the film needs to be removed from that of the sample. This requires the calculation of unique deconvolution parameters for the film. The development of a reconstruction procedure for a contained/covered sample is described.

  12. Visual Selective Attention in Mice.

    Science.gov (United States)

    Wang, Lupeng; Krauzlis, Richard J

    2018-02-08

    Visual selective attention is a fundamental cognitive ability that allows us to process relevant visual stimuli while ignoring irrelevant distracters and has been extensively studied in human and non-human primate subjects. Mice have emerged as a powerful animal model for studying aspects of the visual system but have not yet been shown to exhibit visual selective attention. Differences in the organization of the visual systems of primates and mice raise the possibility that selective visual attention might not be present in mice, at least not in the forms that are well established in primates. Here, we tested for selective visual attention in mice by using three behavioral paradigms adapted from classic studies of attention. In a Posner-style cueing task, a spatial cue indicated the probable location of the relevant visual event, and we found that accuracy was higher and reaction times were shorter on validly cued trials. In a cue versus no-cue task, an informative spatial cue was provided on half the trials, and mice had higher accuracy and shorter reaction times with spatial cues and also lower detection thresholds measured from psychometric curves. In a filter task, the spatial cue indicated the location of the relevant visual event, and we found that mice could be trained to ignore irrelevant but otherwise identical visual events at uncued locations. Together, these results demonstrate that mice exhibit visual selective attention, paving the way to use classic attention paradigms in mice to study the genetic and neuronal circuit mechanisms of selective attention. Published by Elsevier Ltd.

  13. Delayed breast implant reconstruction

    DEFF Research Database (Denmark)

    Hvilsom, Gitte B.; Hölmich, Lisbet R.; Steding-Jessen, Marianne

    2011-01-01

    Studies of complications following reconstructive surgery with implants among women with breast cancer are needed. As the, to our knowledge, first prospective long-term study we evaluated the occurrence of complications following delayed breast reconstruction separately for one- and two-stage pro......Studies of complications following reconstructive surgery with implants among women with breast cancer are needed. As the, to our knowledge, first prospective long-term study we evaluated the occurrence of complications following delayed breast reconstruction separately for one- and two......-stage procedures. From the Danish Registry for Plastic Surgery of the Breast, which has prospectively registered data for women undergoing breast implantations since 1999, we identified 559 women without a history of radiation therapy undergoing 592 delayed breast reconstructions following breast cancer during...... the period 1999 to 2006; 239 one-stage procedures and 353 two-stage procedures. The postoperative course through November 2009 was evaluated by cumulative incidence adjusting for competing risks for the selected outcomes; hematoma, infection, seroma, implant rupture, severe capsular contracture (modified...

  14. Permutationally invariant state reconstruction

    DEFF Research Database (Denmark)

    Moroder, Tobias; Hyllus, Philipp; Tóth, Géza

    2012-01-01

    Feasible tomography schemes for large particle numbers must possess, besides an appropriate data acquisition protocol, an efficient way to reconstruct the density operator from the observed finite data set. Since state reconstruction typically requires the solution of a nonlinear large-scale opti...... optimization, which has clear advantages regarding speed, control and accuracy in comparison to commonly employed numerical routines. First prototype implementations easily allow reconstruction of a state of 20 qubits in a few minutes on a standard computer.......-scale optimization problem, this is a major challenge in the design of scalable tomography schemes. Here we present an efficient state reconstruction scheme for permutationally invariant quantum state tomography. It works for all common state-of-the-art reconstruction principles, including, in particular, maximum...... likelihood and least squares methods, which are the preferred choices in today's experiments. This high efficiency is achieved by greatly reducing the dimensionality of the problem employing a particular representation of permutationally invariant states known from spin coupling combined with convex...

  15. Clinical impact of model-based type iterative reconstruction with fast reconstruction time on image quality of low-dose screening chest CT.

    Science.gov (United States)

    Yuki, Hideaki; Oda, Seitaro; Utsunomiya, Daisuke; Funama, Yoshinori; Kidoh, Masafumi; Namimoto, Tomohiro; Katahira, Kazuhiro; Honda, Keiichi; Tokuyasu, Shinichi; Yamashita, Yasuyuki

    2016-03-01

    Model-based type iterative reconstruction algorithms with fast reconstruction times are now available. The clinical feasibility of their reconstruction has not been evaluated adequately. To investigate the effects of model-based type iterative reconstruction, i.e. iterative model reconstruction (IMR), with fast reconstruction time on the qualitative and quantitative image quality at low-dose chest computed tomography (CT). Thirty-one patients undergoing low-dose screening chest CT were enrolled. Images were reconstructed using filtered back projection (FBP), hybrid iterative reconstruction (HIR), and IMR algorithms. The CT attenuation and image noise for all reconstructions were calculated at the lung apex, middle, and base. Using a 4-point scale, two reviewers visually evaluated the image quality with respect to vessel sharpness, streak artifact, the mediastinum, and the overall image quality of each reconstruction method. The mean estimated effective dose was 1.0 ± 0.3 mSv. There was no significant difference in the CT attenuation among the three reconstructions. The mean image noise of FBP, HIR, and IMR images was 124.3 ± 57.3, 34.8 ± 10.2, and 22.9 ± 5.8 HU, respectively. There were significant differences for all comparison combinations among the three methods (P reconstruction time for IMR was within 3 min in all cases. At low-dose chest CT, IMR can improve the qualitative and quantitative visualization of both lung and mediastinal structures especially in the lung apex at a clinically acceptable reconstruction time. Its application may improve diagnostic performance. © The Foundation Acta Radiologica 2015.

  16. A Post-Rectification Approach of Depth Images of Kinect v2 for 3D Reconstruction of Indoor Scenes

    Directory of Open Access Journals (Sweden)

    Jichao Jiao

    2017-11-01

    Full Text Available 3D reconstruction of indoor scenes is a hot research topic in computer vision. Reconstructing fast, low-cost, and accurate dense 3D maps of indoor scenes have applications in indoor robot positioning, navigation, and semantic mapping. In other studies, the Microsoft Kinect for Windows v2 (Kinect v2 is utilized to complete this task, however, the accuracy and precision of depth information and the accuracy of correspondence between the RGB and depth (RGB-D images still remain to be improved. In this paper, we propose a post-rectification approach of the depth images to improve the accuracy and precision of depth information. Firstly, we calibrate the Kinect v2 with a planar checkerboard pattern. Secondly, we propose a post-rectification approach of the depth images according to the reflectivity-related depth error. Finally, we conduct tests to evaluate this post-rectification approach from the perspectives of accuracy and precision. In order to validate the effect of our post-rectification approach, we apply it to RGB-D simultaneous localization and mapping (SLAM in an indoor environment. Experimental results show that once our post-rectification approach is employed, the RGB-D SLAM system can perform a more accurate and better visual effect 3D reconstruction of indoor scenes than other state-of-the-art methods.

  17. Revision Anterior Cruciate Ligament Reconstruction: Results of a Single-stage Approach Using Allograft Dowel Bone Grafting for Femoral Defects.

    Science.gov (United States)

    Werner, Brian C; Gilmore, Carl J; Hamann, Joshua C; Gaskin, Cree M; Carroll, John J; Hart, Joseph M; Miller, Mark D

    2016-08-01

    The purpose of this study was to present results of single-stage revision anterior cruciate ligament (ACL) reconstruction using an allograft bone dowel for isolated femoral bony deficiency. Sixteen patients underwent single-stage revision ACL reconstruction using an allograft bone dowel for isolated femoral bony deficiency between 2007 and 2012. Twelve patients (75%) completed study visits, which included CT scans as well as completion of validated outcomes measures. The average KT-1000 side-to-side difference was 1.0 mm ± 2.9 mm. The average International Knee Documentation Committee score was 70.2 ± 17.8, the Tegner score was 4.8 ± 2.8, and the visual analog scale pain score was 2.8 ± 2.4. An analysis of CT scans showed that all 12 dowels had excellent (>75%) incorporation. A single-stage approach for revision ACL reconstruction using allograft dowels for isolated femoral bony deficiency yields objective and subjective outcomes comparable to those reported in the literature for two-stage and other single-stage techniques, with good incorporation of the dowels. Retrospective case series, level IV.

  18. Quantification of perfusion in murine myocardium: A retrospectively triggered T1 -based ASL method using model-based reconstruction.

    Science.gov (United States)

    Gutjahr, Fabian T; Kampf, Thomas; Winter, Patrick; Meyer, Cord B; Williams, Tatjana; Jakob, Peter M; Bauer, Wolfgang R; Ziener, Christian H; Helluy, Xavier

    2015-12-01

    A method for the quantification of perfusion in murine myocardium is demonstrated. The method allows for the reconstruction of perfusion maps on arbitrary time points in the heart cycle while addressing problems that arise due to the irregular heart beat of mice. A flow-sensitive alternating inversion recovery arterial spin labeling method using an untriggered FLASH-read out with random sampling is used. Look-Locker conditions are strictly maintained. No dummy pulses or mechanism to reduce deviation from Look-Locker conditions are needed. Electrocardiogram and respiratory data are recorded for retrospective gating and triggering. A model-based technique is used to reconstruct missing k-space data to cope with the undersampling inherent in retrospectively gated methods. Acquisition and reconstruction were validated numerically and in phantom measurements before in vivo experimentation. Quantitative perfusion maps were acquired within a single slice measurement time of 11 min. Perfusion values are in good accordance to literature values. Myocardial infarction could be clearly visualized and results were confirmed with histological results. The proposed method is capable of producing quantitative perfusion maps on arbitrary positions in the heart cycle within a short measurement time. The method is robust against irregular breathing patterns and heart rate changes and can be implemented on all scanners. © 2014 Wiley Periodicals, Inc.

  19. Comparison of model-observer and human-observer performance for breast tomosynthesis: effect of reconstruction and acquisition parameters

    Science.gov (United States)

    Das, Mini; Gifford, Howard C.

    2011-03-01

    The problem of optimizing the acquisition and reconstruction parameters for breast-cancer detection with digital breast tomosynthesis (DBT) is becoming increasingly important due to the potential of DBT for clinical screening. Ideally, one wants a set of parameters suitable for both microcalcification (MC) and mass detection that specifies the lowest possible radiation dose to the patient. Attacking this multiparametric optimization problem using human-observer studies (which are the gold standard) would be very expensive. On the other hand, there are numerous limitations to having existing mathematical model observers as replacements. Our aim is to develop a model observer that can reliably mimic human observers at clinically realistic DBT detection tasks. In this paper, we present a novel visual-search (VS) model observer for MC detection and localization. Validation of this observer against human data was carried out in a study with simulated DBT test images. Radiation dose was a study parameter, with tested acquisition levels of 0.7, 1.0 and 1.5 mGy. All test images were reconstructed with a penalized-maximum-likelihood reconstruction method. Good agreement at all three dose levels was obtained between the VS and human observers. We believe that this new model observer has the potential to take the field of image-quality research in a new direction with a number of practical clinical ramifications.

  20. Study of Track Reconstruction for DAMPE

    Science.gov (United States)

    Lu, Tong-suo; Lei, Shi-jun; Zang, Jing-jing; Chang, Jin; Wu, Jian

    2017-07-01

    The Dark Matter Particle Explorer (DAMPE) is aimed to study the existence and distribution of dark matter via the observation of high-energy particles in space with a large energy bandwidth, high energy resolution, and high spatial resolution. The track reconstruction is to restore the positions and angles of the incident particles using the multiple observations of different channels at different positions, and its accuracy determines the angular resolution of the explorer. The track reconstruction is mainly based on the observations of two sub-detectors, namely, the Silicon Tracker (STK) and the BGO (Bi4Ge3O12) calorimeter. In accordance with the design and structure of the two sub-detectors, and using the data collected during the beam tests and ground tests of cosmic rays, we discuss in detail the method of track reconstruction for the DAMPE, which includes mainly three basic procedures: the selection of track hits, the fitting of track hits, and the judgement of the optimal track. Since an energetic particle most probably leaves multiple hits in different layers of the STK and BGO crystals, we first provide a method to obtain a rough track in the BGO calorimeter by the centroid method, and hereby to constrain the track hits in the STK. Then for the selected one group of possible track hits in the STK, we apply two different algorithms, the Kalman filter and the least square linear fitting, to fit these track hits. The consistency of the results obtained independently via the two algorithms confirms the validity of our track reconstruction results. Finally, several criteria for picking out the most possible track among all the tracks found in the reconstruction by combining the results of the BGO calorimeter and STK are discussed. Using the track reconstruction method proposed in this article and the beam test data, we confirm that the angular resolution of the DAMPE satisfies its design requirement.

  1. Autologous Fat Grafting for Whole Breast Reconstruction

    Directory of Open Access Journals (Sweden)

    Benjamin H. L. Howes, MBBS

    2014-03-01

    Full Text Available Summary: This is the first reported case of a patient who had a single-stage large-volume breast reconstruction with autologous fat grafting, following rotation flap approach (RoFA mastectomy. The purpose of this case study was to evaluate the viability of reconstruction of the breast by autologous fat grafting alone, in the context of RoFA mastectomy. The hypothesis was that there would be minimal interval loss of autologous fat on the whole breast reconstruction side. Right RoFA mastectomy was used for resection of an invasive primary breast cancer and resulted in the right breast skin envelope. Eleven months later, the patient underwent grafting of 400 ml of autologous fat into the skin envelope and underlying pectoralis major muscle. Outcome was assessed by using a validated 3D laser scan technique for quantitative breast volume measurement. Other outcome measures included the BREAST-Q questionnaire and 2D clinical photography. At 12-month follow-up, the patient was observed to have maintenance of volume of the reconstructed breast. Her BREAST-Q scores were markedly improved compared with before fat grafting, and there was observable improvement in shape, contour, and symmetry on 2D clinical photography. The 2 new techniques, RoFA mastectomy and large-volume single-stage autologous fat grafting, were used in combination to achieve a satisfactory postmastectomy breast reconstruction. Novel tools for measurement of outcome were the 3D whole-body laser scanner and BREAST-Q questionnaire. This case demonstrates the potential for the use of fat grafting for reconstruction. Outcomes in a larger patient populations are needed to confirm these findings.

  2. Arctic Sea Level Reconstruction

    DEFF Research Database (Denmark)

    Svendsen, Peter Limkilde

    gauge record and makes the reconstruction much less prone to drifting away over time.Unfortunately, many of the Russian-sector tide gauge records end around 1990,leaving a fairly sparse record after this. This project examines the effect of introducing a subset of the altimetric dataset as “virtual tide......Reconstruction of historical Arctic sea level is very difficult due to the limited coverage and quality of tide gauge and altimetry data in the area. This thesis addresses many of these issues, and discusses strategies to help achieve a stable and plausible reconstruction of Arctic sea level from...... 1950 to today.The primary record of historical sea level, on the order of several decades to a few centuries, is tide gauges. Tide gauge records from around the world are collected in the Permanent Service for Mean Sea Level (PSMSL) database, and includes data along the Arctic coasts. A reasonable...

  3. Iterative initial condition reconstruction

    Science.gov (United States)

    Schmittfull, Marcel; Baldauf, Tobias; Zaldarriaga, Matias

    2017-07-01

    Motivated by recent developments in perturbative calculations of the nonlinear evolution of large-scale structure, we present an iterative algorithm to reconstruct the initial conditions in a given volume starting from the dark matter distribution in real space. In our algorithm, objects are first moved back iteratively along estimated potential gradients, with a progressively reduced smoothing scale, until a nearly uniform catalog is obtained. The linear initial density is then estimated as the divergence of the cumulative displacement, with an optional second-order correction. This algorithm should undo nonlinear effects up to one-loop order, including the higher-order infrared resummation piece. We test the method using dark matter simulations in real space. At redshift z =0 , we find that after eight iterations the reconstructed density is more than 95% correlated with the initial density at k ≤0.35 h Mpc-1 . The reconstruction also reduces the power in the difference between reconstructed and initial fields by more than 2 orders of magnitude at k ≤0.2 h Mpc-1 , and it extends the range of scales where the full broadband shape of the power spectrum matches linear theory by a factor of 2-3. As a specific application, we consider measurements of the baryonic acoustic oscillation (BAO) scale that can be improved by reducing the degradation effects of large-scale flows. In our idealized dark matter simulations, the method improves the BAO signal-to-noise ratio by a factor of 2.7 at z =0 and by a factor of 2.5 at z =0.6 , improving standard BAO reconstruction by 70% at z =0 and 30% at z =0.6 , and matching the optimal BAO signal and signal-to-noise ratio of the linear density in the same volume. For BAO, the iterative nature of the reconstruction is the most important aspect.

  4. Vertex Reconstruction in CMS

    CERN Document Server

    Chabanat, E; D'Hondt, J; Vanlaer, P; Prokofiev, K; Speer, T; Frühwirth, R; Waltenberger, W

    2005-01-01

    Because of the high track multiplicity in the final states expected in proton collisions at the LHC experiments, novel vertex reconstruction algorithms are required. The vertex reconstruction problem can be decomposed into a pattern recognition problem ("vertex finding") and an estimation problem ("vertex fitting"). Starting from least-square methods, ways to render the classical algorithms more robust are discussed and the statistical properties of the novel methods are shown. A whole set of different approaches for the vertex finding problem is presented and compared in relevant physics channels.

  5. An Intelligent Cooperative Visual Sensor Network for Urban Mobility

    Directory of Open Access Journals (Sweden)

    Giuseppe Riccardo Leone

    2017-11-01

    Full Text Available Smart cities are demanding solutions for improved traffic efficiency, in order to guarantee optimal access to mobility resources available in urban areas. Intelligent video analytics deployed directly on board embedded sensors offers great opportunities to gather highly informative data about traffic and transport, allowing reconstruction of a real-time neat picture of urban mobility patterns. In this paper, we present a visual sensor network in which each node embeds computer vision logics for analyzing in real time urban traffic. The nodes in the network share their perceptions and build a global and comprehensive interpretation of the analyzed scenes in a cooperative and adaptive fashion. This is possible thanks to an especially designed Internet of Things (IoT compliant middleware which encompasses in-network event composition as well as full support of Machine-2-Machine (M2M communication mechanism. The potential of the proposed cooperative visual sensor network is shown with two sample applications in urban mobility connected to the estimation of vehicular flows and parking management. Besides providing detailed results of each key component of the proposed solution, the validity of the approach is demonstrated by extensive field tests that proved the suitability of the system in providing a scalable, adaptable and extensible data collection layer for managing and understanding mobility in smart cities.

  6. An Intelligent Cooperative Visual Sensor Network for Urban Mobility.

    Science.gov (United States)

    Leone, Giuseppe Riccardo; Moroni, Davide; Pieri, Gabriele; Petracca, Matteo; Salvetti, Ovidio; Azzarà, Andrea; Marino, Francesco

    2017-11-10

    Smart cities are demanding solutions for improved traffic efficiency, in order to guarantee optimal access to mobility resources available in urban areas. Intelligent video analytics deployed directly on board embedded sensors offers great opportunities to gather highly informative data about traffic and transport, allowing reconstruction of a real-time neat picture of urban mobility patterns. In this paper, we present a visual sensor network in which each node embeds computer vision logics for analyzing in real time urban traffic. The nodes in the network share their perceptions and build a global and comprehensive interpretation of the analyzed scenes in a cooperative and adaptive fashion. This is possible thanks to an especially designed Internet of Things (IoT) compliant middleware which encompasses in-network event composition as well as full support of Machine-2-Machine (M2M) communication mechanism. The potential of the proposed cooperative visual sensor network is shown with two sample applications in urban mobility connected to the estimation of vehicular flows and parking management. Besides providing detailed results of each key component of the proposed solution, the validity of the approach is demonstrated by extensive field tests that proved the suitability of the system in providing a scalable, adaptable and extensible data collection layer for managing and understanding mobility in smart cities.

  7. Visualizing Practices in Project-based Design

    DEFF Research Database (Denmark)

    Whyte, Jennifer; Tryggestad, Kjell; Comi, Alice

    2016-01-01

    Project-based design involves a variety of visual representations, which are evolved to make decisions and accomplish project objectives. Yet, such mediated and distributed ways of working are difficult to capture through ethnographies that examine situated design. A novel approach is developed...... that follows cascades of visual representations, and this is illustrated through two empirical studies. In the first case, Heathrow Terminal 5, analysis starts from paper- and model-work used to develop design, tracing connections forward to an assembly manual that forms a ‘consolidated cascade’ of visual...... of situated design. This allows the researcher to be nimble, tracing connections across complex engineering projects; reconstructing practices through their visual representations; and observing their effects. Second, it articulates how, in these empirical cases, interaction with a cascade of visual...

  8. Reconstruction dynamics of recorded holograms in photochromic glass.

    Science.gov (United States)

    Mihailescu, Mona; Pavel, Eugen; Nicolae, Vasile B

    2011-06-20

    We have investigated the dynamics of the record-erase process of holograms in photochromic glass using continuum Nd:YVO₄ laser radiation (λ=532 nm). A bidimensional microgrid pattern was formed and visualized in photochromic glass, and its diffraction efficiency decay versus time (during reconstruction step) gave us information (D, Δn) about the diffusion process inside the material. The recording and reconstruction processes were carried out in an off-axis setup, and the images of the reconstructed object were recorded by a CCD camera. Measurements realized on reconstructed object images using holograms recorded at a different incident power laser have shown a two-stage process involved in silver atom kinetics.

  9. Reconstruction dynamics of recorded holograms in photochromic glass

    Energy Technology Data Exchange (ETDEWEB)

    Mihailescu, Mona; Pavel, Eugen; Nicolae, Vasile B.

    2011-06-20

    We have investigated the dynamics of the record-erase process of holograms in photochromic glass using continuum Nd:YVO{sub 4} laser radiation ({lambda}=532 nm). A bidimensional microgrid pattern was formed and visualized in photochromic glass, and its diffraction efficiency decay versus time (during reconstruction step) gave us information (D, {Delta}n) about the diffusion process inside the material. The recording and reconstruction processes were carried out in an off-axis setup, and the images of the reconstructed object were recorded by a CCD camera. Measurements realized on reconstructed object images using holograms recorded at a different incident power laser have shown a two-stage process involved in silver atom kinetics.

  10. Periocular Reconstruction in Patients with Facial Paralysis.

    Science.gov (United States)

    Joseph, Shannon S; Joseph, Andrew W; Douglas, Raymond S; Massry, Guy G

    2016-04-01

    Facial paralysis can result in serious ocular consequences. All patients with orbicularis oculi weakness in the setting of facial nerve injury should undergo a thorough ophthalmologic evaluation. The main goal of management in these patients is to protect the ocular surface and preserve visual function. Patients with expected recovery of facial nerve function may only require temporary and conservative measures to protect the ocular surface. Patients with prolonged or unlikely recovery of facial nerve function benefit from surgical rehabilitation of the periorbital complex. Current reconstructive procedures are most commonly intended to improve coverage of the eye but cannot restore blink. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Visualizing Transformation

    DEFF Research Database (Denmark)

    Pedersen, Pia

    2012-01-01

    the finished charts as a starting point and then going back to the beginning; furthermore, this inquiry presents a novel approach to clarifying the process by designing symbols and diagrams. It will be demonstrated that transformation offers an improved approach to data visualization. The message in the chart...... is not preformed, but formed through the process of transformation; this means that the purpose of transformation is not the styling of charts with pictograms, but rather creating a meaningful message. The contribution of this paper is an elaborated understanding of the process of transformation...... design. Recently transformation has attracted renewed interest because of the book The Transformer written by Robin Kinross and Marie Neurath. My on-going research project, summarized in this paper, identifies and depicts the essential principles of data visualization underlying the process...

  12. Looking for the Signal: A guide to iterative noise and artefact removal in X-ray tomographic reconstructions of porous geomaterials

    Science.gov (United States)

    Bruns, S.; Stipp, S. L. S.; Sørensen, H. O.

    2017-07-01

    X-ray micro- and nanotomography has evolved into a quantitative analysis tool rather than a mere qualitative visualization technique for the study of porous natural materials. Tomographic reconstructions are subject to noise that has to be handled by image filters prior to quantitative analysis. Typically, denoising filters are designed to handle random noise, such as Gaussian or Poisson noise. In tomographic reconstructions, noise has been projected from Radon space to Euclidean space, i.e. post reconstruction noise cannot be expected to be random but to be correlated. Reconstruction artefacts, such as streak or ring artefacts, aggravate the filtering process so algorithms performing well with random noise are not guaranteed to provide satisfactory results for X-ray tomography reconstructions. With sufficient image resolution, the crystalline origin of most geomaterials results in tomography images of objects that are untextured. We developed a denoising framework for these kinds of samples that combines a noise level estimate with iterative nonlocal means denoising. This allows splitting the denoising task into several weak denoising subtasks where the later filtering steps provide a controlled level of texture removal. We describe a hands-on explanation for the use of this iterative denoising approach and the validity and quality of the image enhancement filter was evaluated in a benchmarking experiment with noise footprints of a varying level of correlation and residual artefacts. They were extracted from real tomography reconstructions. We found that our denoising solutions were superior to other denoising algorithms, over a broad range of contrast-to-noise ratios on artificial piecewise constant signals.

  13. Bio-physically plausible visualization of highly scattering fluorescent neocortical models for in silico experimentation

    KAUST Repository

    Abdellah, Marwan

    2017-02-15

    Background We present a visualization pipeline capable of accurate rendering of highly scattering fluorescent neocortical neuronal models. The pipeline is mainly developed to serve the computational neurobiology community. It allows the scientists to visualize the results of their virtual experiments that are performed in computer simulations, or in silico. The impact of the presented pipeline opens novel avenues for assisting the neuroscientists to build biologically accurate models of the brain. These models result from computer simulations of physical experiments that use fluorescence imaging to understand the structural and functional aspects of the brain. Due to the limited capabilities of the current visualization workflows to handle fluorescent volumetric datasets, we propose a physically-based optical model that can accurately simulate light interaction with fluorescent-tagged scattering media based on the basic principles of geometric optics and Monte Carlo path tracing. We also develop an automated and efficient framework for generating dense fluorescent tissue blocks from a neocortical column model that is composed of approximately 31000 neurons. Results Our pipeline is used to visualize a virtual fluorescent tissue block of 50 μm3 that is reconstructed from the somatosensory cortex of juvenile rat. The fluorescence optical model is qualitatively analyzed and validated against experimental emission spectra of different fluorescent dyes from the Alexa Fluor family. Conclusion We discussed a scientific visualization pipeline for creating images of synthetic neocortical neuronal models that are tagged virtually with fluorescent labels on a physically-plausible basis. The pipeline is applied to analyze and validate simulation data generated from neuroscientific in silico experiments.

  14. Bio-physically plausible visualization of highly scattering fluorescent neocortical models for in silico experimentation.

    Science.gov (United States)

    Abdellah, Marwan; Bilgili, Ahmet; Eilemann, Stefan; Shillcock, Julian; Markram, Henry; Schürmann, Felix

    2017-02-15

    We present a visualization pipeline capable of accurate rendering of highly scattering fluorescent neocortical neuronal models. The pipeline is mainly developed to serve the computational neurobiology community. It allows the scientists to visualize the results of their virtual experiments that are performed in computer simulations, or in silico. The impact of the presented pipeline opens novel avenues for assisting the neuroscientists to build biologically accurate models of the brain. These models result from computer simulations of physical experiments that use fluorescence imaging to understand the structural and functional aspects of the brain. Due to the limited capabilities of the current visualization workflows to handle fluorescent volumetric datasets, we propose a physically-based optical model that can accurately simulate light interaction with fluorescent-tagged scattering media based on the basic principles of geometric optics and Monte Carlo path tracing. We also develop an automated and efficient framework for generating dense fluorescent tissue blocks from a neocortical column model that is composed of approximately 31000 neurons. Our pipeline is used to visualize a virtual fluorescent tissue block of 50 μm3 that is reconstructed from the somatosensory cortex of juvenile rat. The fluorescence optical model is qualitatively analyzed and validated against experimental emission spectra of different fluorescent dyes from the Alexa Fluor family. We discussed a scientific visualization pipeline for creating images of synthetic neocortical neuronal models that are tagged virtually with fluorescent labels on a physically-plausible basis. The pipeline is applied to analyze and validate simulation data generated from neuroscientific in silico experiments.

  15. Visualizing Progress

    Science.gov (United States)

    2000-01-01

    Reality Capture Technologies, Inc. is a spinoff company from Ames Research Center. Offering e-business solutions for optimizing management, design and production processes, RCT uses visual collaboration environments (VCEs) such as those used to prepare the Mars Pathfinder mission.The product, 4-D Reality Framework, allows multiple users from different locations to manage and share data. The insurance industry is one targeted commercial application for this technology.

  16. Visualizing thought.

    Science.gov (United States)

    Tversky, Barbara

    2011-07-01

    Depictive expressions of thought predate written language by thousands of years. They have evolved in communities through a kind of informal user testing that has refined them. Analyzing common visual communications reveals consistencies that illuminate how people think as well as guide design; the process can be brought into the laboratory and accelerated. Like language, visual communications abstract and schematize; unlike language, they use properties of the page (e.g., proximity and place: center, horizontal/up-down, vertical/left-right) and the marks on it (e.g., dots, lines, arrows, boxes, blobs, likenesses, symbols) to convey meanings. The visual expressions of these meanings (e.g., individual, category, order, relation, correspondence, continuum, hierarchy) have analogs in language, gesture, and especially in the patterns that are created when people design the world around them, arranging things into piles and rows and hierarchies and arrays, spatial-abstraction-action interconnections termed spractions. The designed world is a diagram. Copyright © 2010 Cognitive Science Society, Inc.

  17. Reconstruction of Peripelvic Oncologic Defects.

    Science.gov (United States)

    Weichman, Katie E; Matros, Evan; Disa, Joseph J

    2017-10-01

    After studying this article, the participant should be able to: 1. Understand the anatomy of the peripelvic area. 2. Understand the advantages and disadvantages of performing peripelvic reconstruction in patients undergoing oncologic resection. 3. Select the appropriate local, pedicled, or free-flap reconstruction based on the location of the defect and donor-site characteristics. Peripelvic reconstruction most commonly occurs in the setting of oncologic ablative surgery. The peripelvic area contains several distinct reconstructive regions, including vagina, vulva, penis, and scrotum. Each area provides unique reconstructive considerations. In addition, prior or future radiation therapy or chemotherapy along with cancer cachexia can increase the complexity of reconstruction.

  18. Simultaneous maximum a posteriori longitudinal PET image reconstruction

    Science.gov (United States)

    Ellis, Sam; Reader, Andrew J.

    2017-09-01

    Positron emission tomography (PET) is frequently used to monitor functional changes that occur over extended time scales, for example in longitudinal oncology PET protocols that include routine clinical follow-up scans to assess the efficacy of a course of treatment. In these contexts PET datasets are currently reconstructed into images using single-dataset reconstruction methods. Inspired by recently proposed joint PET-MR reconstruction methods, we propose to reconstruct longitudinal datasets simultaneously by using a joint penalty term in order to exploit the high degree of similarity between longitudinal images. We achieved this by penalising voxel-wise differences between pairs of longitudinal PET images in a one-step-late maximum a posteriori (MAP) fashion, resulting in the MAP simultaneous longitudinal reconstruction (SLR) method. The proposed method reduced reconstruction errors and visually improved images relative to standard maximum likelihood expectation-maximisation (ML-EM) in simulated 2D longitudinal brain tumour scans. In reconstructions of split real 3D data with inserted simulated tumours, noise across images reconstructed with MAP-SLR was reduced to levels equivalent to doubling the number of detected counts when using ML-EM. Furthermore, quantification of tumour activities was largely preserved over a variety of longitudinal tumour changes, including changes in size and activity, with larger changes inducing larger biases relative to standard ML-EM reconstructions. Similar improvements were observed for a range of counts levels, demonstrating the robustness of the method when used with a single penalty strength. The results suggest that longitudinal regularisation is a simple but effective method of improving reconstructed PET images without using resolution degrading priors.

  19. Reconstructing complex networks without time series

    Science.gov (United States)

    Ma, Chuang; Zhang, Hai-Feng; Lai, Ying-Cheng

    2017-08-01

    In the real world there are situations where the network dynamics are transient (e.g., various spreading processes) and the final nodal states represent the available data. Can the network topology be reconstructed based on data that are not time series? Assuming that an ensemble of the final nodal states resulting from statistically independent initial triggers (signals) of the spreading dynamics is available, we develop a maximum likelihood estimation-based framework to accurately infer the interaction topology. For dynamical processes that result in a binary final state, the framework enables network reconstruction based solely on the final nodal states. Additional information, such as the first arrival time of each signal at each node, can improve the reconstruction accuracy. For processes with a uniform final state, the first arrival times can be exploited to reconstruct the network. We derive a mathematical theory for our framework and validate its performance and robustness using various combinations of spreading dynamics and real-world network topologies.

  20. Reducing the effects of acoustic heterogeneity with an iterative reconstruction method from experimental data in microwave induced thermoacoustic tomography.

    Science.gov (United States)

    Wang, Jinguo; Zhao, Zhiqin; Song, Jian; Chen, Guoping; Nie, Zaiping; Liu, Qing-Huo

    2015-05-01

    An iterative reconstruction method has been previously reported by the authors of this paper. However, the iterative reconstruction method was demonstrated by solely using the numerical simulations. It is essential to apply the iterative reconstruction method to practice conditions. The objective of this work is to validate the capability of the iterative reconstruction method for reducing the effects of acoustic heterogeneity with the experimental data in microwave induced thermoacoustic tomography. Most existing reconstruction methods need to combine the ultrasonic measurement technology to quantitatively measure the velocity distribution of heterogeneity, which increases the system complexity. Different to existing reconstruction methods, the iterative reconstruction method combines time reversal mirror technique, fast marching method, and simultaneous algebraic reconstruction technique to iteratively estimate the velocity distribution of heterogeneous tissue by solely using the measured data. Then, the estimated velocity distribution is used subsequently to reconstruct the highly accurate image of microwave absorption distribution. Experiments that a target placed in an acoustic heterogeneous environment are performed to validate the iterative reconstruction method. By using the estimated velocity distribution, the target in an acoustic heterogeneous environment can be reconstructed with better shape and higher image contrast than targets that are reconstructed with a homogeneous velocity distribution. The distortions caused by the acoustic heterogeneity can be efficiently corrected by utilizing the velocity distribution estimated by the iterative reconstruction method. The advantage of the iterative reconstruction method over the existing correction methods is that it is successful in improving the quality of the image of microwave absorption distribution without increasing the system complexity.

  1. High resolution acoustic measurement system and beam pattern reconstruction method for bat echolocation emissions.

    Science.gov (United States)

    Gaudette, Jason E; Kloepper, Laura N; Warnecke, Michaela; Simmons, James A

    2014-01-01

    Measurements of the transmit beam patterns emitted by echolocating bats have previously been limited to cross-sectional planes or averaged over multiple signals using sparse microphone arrays. To date, no high-resolution measurements of individual bat transmit beams have been reported in the literature. Recent studies indicate that bats may change the time-frequency structure of their calls depending on the task, and suggest that their beam patterns are more dynamic than previously thought. To investigate beam pattern dynamics in a variety of bat species, a high-density reconfigurable microphone array was designed and constructed using low-cost ultrasonic microphones and custom electronic circuitry. The planar array is 1.83 m wide by 1.42 m tall with microphones positioned on a 2.54 cm square grid. The system can capture up to 228 channels simultaneously at a 500 kHz sampling rate. Beam patterns are reconstructed in azimuth, elevation, and frequency for visualization and further analysis. Validation of the array measurement system and post-processing functions is shown by reconstructing the beam pattern of a transducer with a fixed circular aperture and comparing the result with a theoretical model. To demonstrate the system in use, transmit beam patterns of the big brown bat, Eptesicus fuscus, are shown.

  2. Volumetric reconstruction from printed films: Enabling 30 year longitudinal analysis in MR neuroimaging.

    Science.gov (United States)

    Ebner, Michael; Chung, Karen K; Prados, Ferran; Cardoso, M Jorge; Chard, Declan T; Vercauteren, Tom; Ourselin, Sébastien

    2018-01-15

    Hospitals often hold historical MR image data printed on films without being able to make it accessible to modern image processing techniques. Having the possibility to recover geometrically consistent, volumetric images from scans acquired decades ago will enable more comprehensive, longitudinal studies to understand disease progressions. In this paper, we propose a consistent framework to reconstruct a volumetric representation from printed films holding thick single-slice brain MR image acquisitions dating back to the 1980's. We introduce a flexible framework based on semi-automatic slice extraction, followed by automated slice-to-volume registration with inter-slice transformation regularisation and slice intensity correction. Our algorithm is robust against numerous detrimental effects being present in archaic films. A subsequent, isotropic total variation deconvolution technique revitalises the visual appearance of the obtained volumes. We assess the accuracy and perform the validation of our reconstruction framework on a uniquely long-term MRI dataset where a ground-truth is available. This method will be used to facilitate a robust longitudinal analysis spanning 30 years of MRI scans. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  3. SPREAD: spatial phylogenetic reconstruction of evolutionary dynamics.

    Science.gov (United States)

    Bielejec, Filip; Rambaut, Andrew; Suchard, Marc A; Lemey, Philippe

    2011-10-15

    SPREAD is a user-friendly, cross-platform application to analyze and visualize Bayesian phylogeographic reconstructions incorporating spatial-temporal diffusion. The software maps phylogenies annotated with both discrete and continuous spatial information and can export high-dimensional posterior summaries to keyhole markup language (KML) for animation of the spatial diffusion through time in virtual globe software. In addition, SPREAD implements Bayes factor calculation to evaluate the support for hypotheses of historical diffusion among pairs of discrete locations based on Bayesian stochastic search variable selection estimates. SPREAD takes advantage of multicore architectures to process large joint posterior distributions of phylogenies and their spatial diffusion and produces visualizations as compelling and interpretable statistical summaries for the different spatial projections. SPREAD is licensed under the GNU Lesser GPL and its source code is freely available as a GitHub repository: https://github.com/phylogeography/SPREAD CONTACT: filip.bielejec@rega.kuleuven.be.

  4. [Aniridia-IOL and artificial iris reconstruction].

    Science.gov (United States)

    Thomas, B C; Rabsilber, T M; Auffarth, G U

    2013-08-01

    Aniridia is defined as missing iris tissue which can be partial, subtotal or total. Characteristic clinical symptoms include photophobia and decreased visual acuity due to an increased light perception. In addition, disturbing cosmetic problems are prevalent. Modern iris reconstruction implants offer visual and cosmetic rehabilitation. Amongst them are aniridia intraocular lenses (IOL), iris segment implants and the "artificial iris". Different overall and pupil diameters are available for total or partial implants. At the same time aphakia or cataract can be treated when using aniridia IOLs. Intra- and extracapsular fixation is possible. The "artificial iris" can be folded and implanted through small incisions. The aesthetic results are improved significantly due to customised colour selection providing increased patient satisfaction postoperatively. Georg Thieme Verlag KG Stuttgart · New York.

  5. Enhanced visualization of the retinal vasculature using depth information in OCT.

    Science.gov (United States)

    de Moura, Joaquim; Novo, Jorge; Charlón, Pablo; Barreira, Noelia; Ortega, Marcos

    2017-12-01

    Retinal vessel tree extraction is a crucial step for analyzing the microcirculation, a frequently needed process in the study of relevant diseases. To date, this has normally been done by using 2D image capture paradigms, offering a restricted visualization of the real layout of the retinal vasculature. In this work, we propose a new approach that automatically segments and reconstructs the 3D retinal vessel tree by combining near-infrared reflectance retinography information with Optical Coherence Tomography (OCT) sections. Our proposal identifies the vessels, estimates their calibers, and obtains the depth at all the positions of the entire vessel tree, thereby enabling the reconstruction of the 3D layout of the complete arteriovenous tree for subsequent analysis. The method was tested using 991 OCT images combined with their corresponding near-infrared reflectance retinography. The different stages of the methodology were validated using the opinion of an expert as a reference. The tests offered accurate results, showing coherent reconstructions of the 3D vasculature that can be analyzed in the diagnosis of relevant diseases affecting the retinal microcirculation, such as hypertension or diabetes, among others.

  6. Craniofacial reconstruction - slideshow

    Science.gov (United States)

    ... GO GO About MedlinePlus Site Map FAQs Customer Support Health Topics Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Craniofacial reconstruction - series—Normal anatomy URL of this page: //medlineplus.gov/ency/presentations/ ...

  7. Reconstructing Community History

    Science.gov (United States)

    Shields, Amy

    2004-01-01

    History is alive and well in Lebanon, Missouri. Students in this small town in the southwest region of the state went above and beyond the community's expectations on this special project. This article describes this historical journey which began when students in a summer mural class reconstructed a mural that was originally created by a…

  8. 'grass roots' reconstructive action

    African Journals Online (AJOL)

    The paper discusses a two year action research investigation of conceptual, evaluation and adoption tensions that led to a revised approach to environmental ... a sustained dialogue around the prevailing science curriculum, local environmental issues and everyday classroom activities fostered reconstructive change at a ...

  9. Urogenital Reconstructive Surgery

    DEFF Research Database (Denmark)

    Jakobsen, Lotte Kaasgaard

    Urogenital reconstructive surgery Lotte Kaasgaard Jakobsen1 Professor Henning Olsen1 Overlæge Gitte Hvistendahl1 Professor Karl-Erik Andersson2 1 – Dept. of Urology, Aarhus University Hospital 2 – Dept. of Gynecology and Obstetrics, Aarhus University hospital Background: Congenital obstruction...

  10. Reconstructing Progressive Education

    Science.gov (United States)

    Kaplan, Andy

    2013-01-01

    The work of Colonel Francis W. Parker, the man whom Dewey called "the father of progressive education," provides a starting point for reconstructing the loose ambiguities of progressive education into a coherent social and educational philosophy. Although progressives have claimed their approach is more humane and sensitive to children, we need…

  11. Optimization of the volume reconstruction for classical Tomo-PIV algorithms (MART, BIMART and SMART): synthetic and experimental studies

    Science.gov (United States)

    Thomas, L.; Tremblais, B.; David, L.

    2014-03-01

    Optimization of multiplicative algebraic reconstruction technique (MART), simultaneous MART and block iterative MART reconstruction techniques was carried out on synthetic and experimental data. Different criteria were defined to improve the preprocessing of the initial images. Knowledge of how each reconstruction parameter influences the quality of particle volume reconstruction and computing time is the key in Tomo-PIV. These criteria were applied to a real case, a jet in cross flow, and were validated.

  12. Breast reconstruction: Correlation between different procedures, reconstruction timing and complications

    Directory of Open Access Journals (Sweden)

    Anđelkov Katarina

    2011-01-01

    Full Text Available Introduction. Improved psychophysical condition after breast reconstruction in women has been well documented Objective. To determine the most optimal technique with minimal morbidity, the authors examined their results and complications based on reconstruction timing (immediate and delayed reconstruction and three reconstruction methods: TRAM flap, latissimus dorsi flap and reconstruction with tissue expanders and implants. Methods. Reconstruction was performed in 60 women of mean age 51.1 years. We analyzed risk factors: age, body mass index (BMI, smoking history and radiation therapy in correlation with timing and method of reconstruction. Complications of all three methods of reconstruction were under 1.5-2-year follow-up after the reconstruction. All data were statistically analyzed. Results. Only radiation had significant influence on the occurrence of complications both before and after the reconstruction, while age, smoking and BMI had no considerable influence of the development of complications. There were no statistically significant correlation between the incidence of complications, time and method of reconstruction. Conclusion. Any of the aforementioned breast reconstruction techniques can yield good results and a low rate of re-operations. To choose the best method, the patient needs to be as well informed as possible about the options including the risks and benefits of each method.

  13. REVEAL: Reconstruction, Enhancement, Visualization, and Ergonomic Assessment for Laparoscopy

    Science.gov (United States)

    2008-08-01

    internal forces generated by ligaments ( anterior and posterior cruciate and medial and lateral collateral ligaments ) and muscles (quadriceps, hamstring...NV, April 18-22, 2007 Lee G, Surgical Ergonomics in Minimally Invasive Surgery, Department of Physical Therapy , University of Maryland, MD, April...13 Physical Ergonomics

  14. Car Accident Reconstruction and Head Injury Correlation

    Science.gov (United States)

    Chawla, A.; Grover, V.; Mukherjee, S.; Hassan, A. M.

    2013-04-01

    Estimation of brain damage remains an elusive issue and controlled tests leading to brain damage cannot be carried out on volunteers. This study reconstructs real-world car accidents to estimate the kinematics of the head impact. This data is to be used to estimate the head injury measures through computer simulations and then correlate reported skull as well as brain damage to impact measures; whence validating the head FE model (Willinger, IJCrash 8:605-617, 2003). In this study, two crash cases were reconstructed. Injury correlation was successful in one of these cases in that the injuries to the brain of one of the car drivers could be correlated in terms of type, location and severity when compared with the tolerance limits of relevant injury parameters (Willinger, IJCrash 8:605-617, 2003).

  15. Imaging, Reconstruction, And Display Of Corneal Topography

    Science.gov (United States)

    Klyce, Stephen D.; Wilson, Steven E.

    1989-12-01

    The cornea is the major refractive element in the eye; even minor surface distortions can produce a significant reduction in visual acuity. Standard clinical methods used to evaluate corneal shape include keratometry, which assumes the cornea is ellipsoidal in shape, and photokeratoscopy, which images a series of concentric light rings on the corneal surface. These methods fail to document many of the corneal distortions that can degrade visual acuity. Algorithms have been developed to reconstruct the three dimensional shape of the cornea from keratoscope images, and to present these data in the clinically useful display of color-coded contour maps of corneal surface power. This approach has been implemented on a new generation video keratoscope system (Computed Anatomy, Inc.) with rapid automatic digitization of the image rings by a rule-based approach. The system has found clinical use in the early diagnosis of corneal shape anomalies such as keratoconus and contact lens-induced corneal warpage, in the evaluation of cataract and corneal transplant procedures, and in the assessment of corneal refractive surgical procedures. Currently, ray tracing techniques are being used to correlate corneal surface topography with potential visual acuity in an effort to more fully understand the tolerances of corneal shape consistent with good vision and to help determine the site of dysfunction in the visually impaired.

  16. 3D Membrane Imaging and Porosity Visualization

    KAUST Repository

    Sundaramoorthi, Ganesh

    2016-03-03

    Ultrafiltration asymmetric porous membranes were imaged by two microscopy methods, which allow 3D reconstruction: Focused Ion Beam and Serial Block Face Scanning Electron Microscopy. A new algorithm was proposed to evaluate porosity and average pore size in different layers orthogonal and parallel to the membrane surface. The 3D-reconstruction enabled additionally the visualization of pore interconnectivity in different parts of the membrane. The method was demonstrated for a block copolymer porous membrane and can be extended to other membranes with application in ultrafiltration, supports for forward osmosis, etc, offering a complete view of the transport paths in the membrane.

  17. Visual and Verbal Learning in a Genetic Metabolic Disorder

    Science.gov (United States)

    Spilkin, Amy M.; Ballantyne, Angela O.; Trauner, Doris A.

    2009-01-01

    Visual and verbal learning in a genetic metabolic disorder (cystinosis) were examined in the following three studies. The goal of Study I was to provide a normative database and establish the reliability and validity of a new test of visual learning and memory (Visual Learning and Memory Test; VLMT) that was modeled after a widely used test of…

  18. Multi-scale measures of rugosity, slope and aspect from benthic stereo image reconstructions.

    Directory of Open Access Journals (Sweden)

    Ariell Friedman

    Full Text Available This paper demonstrates how multi-scale measures of rugosity, slope and aspect can be derived from fine-scale bathymetric reconstructions created from geo-referenced stereo imagery. We generate three-dimensional reconstructions over large spatial scales using data collected by Autonomous Underwater Vehicles (AUVs, Remotely Operated Vehicles (ROVs, manned submersibles and diver-held imaging systems. We propose a new method for calculating rugosity in a Delaunay triangulated surface mesh by projecting areas onto the plane of best fit using Principal Component Analysis (PCA. Slope and aspect can be calculated with very little extra effort, and fitting a plane serves to decouple rugosity from slope. We compare the results of the virtual terrain complexity calculations with experimental results using conventional in-situ measurement methods. We show that performing calculations over a digital terrain reconstruction is more flexible, robust and easily repeatable. In addition, the method is non-contact and provides much less environmental impact compared to traditional survey techniques. For diver-based surveys, the time underwater needed to collect rugosity data is significantly reduced and, being a technique based on images, it is possible to use robotic platforms that can operate beyond diver depths. Measurements can be calculated exhaustively at multiple scales for surveys with tens of thousands of images covering thousands of square metres. The technique is demonstrated on data gathered by a diver-rig and an AUV, on small single-transect surveys and on a larger, dense survey that covers over [Formula: see text]. Stereo images provide 3D structure as well as visual appearance, which could potentially feed into automated classification techniques. Our multi-scale rugosity, slope and aspect measures have already been adopted in a number of marine science studies. This paper presents a detailed description of the method and thoroughly validates it

  19. Multi-scale measures of rugosity, slope and aspect from benthic stereo image reconstructions.

    Science.gov (United States)

    Friedman, Ariell; Pizarro, Oscar; Williams, Stefan B; Johnson-Roberson, Matthew

    2012-01-01

    This paper demonstrates how multi-scale measures of rugosity, slope and aspect can be derived from fine-scale bathymetric reconstructions created from geo-referenced stereo imagery. We generate three-dimensional reconstructions over large spatial scales using data collected by Autonomous Underwater Vehicles (AUVs), Remotely Operated Vehicles (ROVs), manned submersibles and diver-held imaging systems. We propose a new method for calculating rugosity in a Delaunay triangulated surface mesh by projecting areas onto the plane of best fit using Principal Component Analysis (PCA). Slope and aspect can be calculated with very little extra effort, and fitting a plane serves to decouple rugosity from slope. We compare the results of the virtual terrain complexity calculations with experimental results using conventional in-situ measurement methods. We show that performing calculations over a digital terrain reconstruction is more flexible, robust and easily repeatable. In addition, the method is non-contact and provides much less environmental impact compared to traditional survey techniques. For diver-based surveys, the time underwater needed to collect rugosity data is significantly reduced and, being a technique based on images, it is possible to use robotic platforms that can operate beyond diver depths. Measurements can be calculated exhaustively at multiple scales for surveys with tens of thousands of images covering thousands of square metres. The technique is demonstrated on data gathered by a diver-rig and an AUV, on small single-transect surveys and on a larger, dense survey that covers over [Formula: see text]. Stereo images provide 3D structure as well as visual appearance, which could potentially feed into automated classification techniques. Our multi-scale rugosity, slope and aspect measures have already been adopted in a number of marine science studies. This paper presents a detailed description of the method and thoroughly validates it against traditional

  20. Adaptive multiresolution method for MAP reconstruction in electron tomography

    Energy Technology Data Exchange (ETDEWEB)

    Acar, Erman, E-mail: erman.acar@tut.fi [Department of Signal Processing, Tampere University of Technology, P.O. Box 553, FI-33101 Tampere (Finland); BioMediTech, Tampere University of Technology, Biokatu 10, 33520 Tampere (Finland); Peltonen, Sari; Ruotsalainen, Ulla [Department of Signal Processing, Tampere University of Technology, P.O. Box 553, FI-33101 Tampere (Finland); BioMediTech, Tampere University of Technology, Biokatu 10, 33520 Tampere (Finland)

    2016-11-15

    3D image reconstruction with electron tomography holds problems due to the severely limited range of projection angles and low signal to noise ratio of the acquired projection images. The maximum a posteriori (MAP) reconstruction methods have been successful in compensating for the missing information and suppressing noise with their intrinsic regularization techniques. There are two major problems in MAP reconstruction methods: (1) selection of the regularization parameter that controls the balance between the data fidelity and the prior information, and (2) long computation time. One aim of this study is to provide an adaptive solution to the regularization parameter selection problem without having additional knowledge about the imaging environment and the sample. The other aim is to realize the reconstruction using sequences of resolution levels to shorten the computation time. The reconstructions were analyzed in terms of accuracy and computational efficiency using a simulated biological phantom and publically available experimental datasets of electron tomography. The numerical and visual evaluations of the experiments show that the adaptive multiresolution method can provide more accurate results than the weighted back projection (WBP), simultaneous iterative reconstruction technique (SIRT), and sequential MAP expectation maximization (sMAPEM) method. The method is superior to sMAPEM also in terms of computation time and usability since it can reconstruct 3D images significantly faster without requiring any parameter to be set by the user. - Highlights: • An adaptive multiresolution reconstruction method is introduced for electron tomography. • The method provides more accurate results than the conventional reconstruction methods. • The missing wedge and noise problems can be compensated by the method efficiently.

  1. Fully 3D iterative CT reconstruction using polar coordinates.

    Science.gov (United States)

    Thibaudeau, Christian; Leroux, Jean-Daniel; Fontaine, Réjean; Lecomte, Roger

    2013-11-01

    This paper demonstrates the feasibility of fully 3D iterative computed tomography reconstruction of highly resolved fields of view using polar coordinates. System matrix is computed using a ray-tracing approach in cylindrical or spherical coordinates. By using polar symmetries inherent to the acquisition geometry, the system matrix size can be reduced by a factor corresponding to the number of acquired projections. Such an important decrease in size allows the system matrix to be precomputed, and loaded all at once into memory prior to reconstruction. By carefully ordering the field of view voxels and the sinogram data, reconstruction speed is also enhanced by a cache-oblivious computer implementation. The reconstruction algorithm is also compatible with the ordered-subsets acceleration method. A final polar-to-Cartesian transformation is applied to the reconstructed image in order to allow proper visualization. The ray-tracing and reconstruction algorithms were implemented in polar representation. Large 3D system matrices were calculated in cylindrical and spherical coordinates, and the performance assessed against Cartesian ray-tracers in terms of speed and memory requirements. Images of analytical phantoms were successfully reconstructed in both cylindrical and spherical coordinates. Fully 3D images of phantoms and small animals were acquired with a Gamma Medica Triumph X-O small animal CT scanner and reconstructed using the manufacturer's software and the proposed polar approach to demonstrate the accuracy and robustness of the later. The noise was found to be reduced while preserving the same level of spatial resolution, without noticeable polar artifacts. Under a reasonable set of assumptions, the memory size of the system matrix can be reduced by a factor corresponding to the number of projections. Using this strategy, iterative reconstruction from high resolution clinical and preclinical systems can be more easily performed using general-purpose personal

  2. Truth Seeded Reconstruction for Fast Simulation in the ATLAS Experiment

    CERN Document Server

    Jansky, Roland; Salzburger, Andreas

    The huge success of the ATLAS experiment for particle physics during Run 1 of the LHC would not have been possible without the production of vast amounts of simulated Monte Carlo data. However, the very detailed detector simulation is a highly CPU intensive task and thus resource shortages occurred. Motivated by this, great effort has been put into speeding up the simulation. As a result, other timeconsuming parts became visible. One of which is the track reconstruction. This thesis describes one potential solution to the CPU intensive reconstruction of simulated data: a newly designed truth seeded reconstruction. At its basics is the idea to skip the pattern recognition altogether, instead utilizing the available (truth) information from simulation to directly fit particle trajectories without searching for them. At the same time tracking effects of the standard reconstruction need to be emulated. This approach is validated thoroughly and no critical deviations of the results compared to the standard reconst...

  3. Arctic sea-level reconstruction analysis using recent satellite altimetry

    DEFF Research Database (Denmark)

    Svendsen, Peter Limkilde; Andersen, Ole Baltazar; Nielsen, Allan Aasbjerg

    2014-01-01

    We present a sea-level reconstruction for the Arctic Ocean using recent satellite altimetry data. The model, forced by historical tide gauge data, is based on empirical orthogonal functions (EOFs) from a calibration period; for this purpose, newly retracked satellite altimetry from ERS-1 and -2...... and Envisat has been used. Despite the limited coverage of these datasets, we have made a reconstruction up to 82 degrees north for the period 1950–2010. We place particular emphasis on determining appropriate preprocessing for the tide gauge data, and on validation of the model, including the ability...... to reconstruct known data. The relationship between the reconstruction and climatic variables, such as atmospheric pressure, and climate oscillations, including the Arctic Oscillation (AO), is examined....

  4. The evolving breast reconstruction

    DEFF Research Database (Denmark)

    Thomsen, Jørn Bo; Gunnarsson, Gudjon Leifur

    2014-01-01

    The aim of this editorial is to give an update on the use of the propeller thoracodorsal artery perforator flap (TAP/TDAP-flap) within the field of breast reconstruction. The TAP-flap can be dissected by a combined use of a monopolar cautery and a scalpel. Microsurgical instruments are generally...... not needed. The propeller TAP-flap can be designed in different ways, three of these have been published: (I) an oblique upwards design; (II) a horizontal design; (III) an oblique downward design. The latissimus dorsi-flap is a good and reliable option for breast reconstruction, but has been criticized...... for morbidity and complications. The TAP-flap does not seem to impair the function of the shoulder or arm and the morbidity appears to be scarce. However, an implant is often needed in combination with the TAP-flap, which results in implant related morbidity over time. The TAP-flap seems to be a promising tool...

  5. How information visualization novices construct visualizations.

    Science.gov (United States)

    Grammel, Lars; Tory, Melanie; Storey, Margaret-Anne

    2010-01-01

    It remains challenging for information visualization novices to rapidly construct visualizations during exploratory data analysis. We conducted an exploratory laboratory study in which information visualization novices explored fictitious sales data by communicating visualization specifications to a human mediator, who rapidly constructed the visualizations using commercial visualization software. We found that three activities were central to the iterative visualization construction process: data attribute selection, visual template selection, and visual mapping specification. The major barriers faced by the participants were translating questions into data attributes, designing visual mappings, and interpreting the visualizations. Partial specification was common, and the participants used simple heuristics and preferred visualizations they were already familiar with, such as bar, line and pie charts. We derived abstract models from our observations that describe barriers in the data exploration process and uncovered how information visualization novices think about visualization specifications. Our findings support the need for tools that suggest potential visualizations and support iterative refinement, that provide explanations and help with learning, and that are tightly integrated into tool support for the overall visual analytics process.

  6. Accelerating electron tomography reconstruction algorithm ICON with GPU.

    Science.gov (United States)

    Chen, Yu; Wang, Zihao; Zhang, Jingrong; Li, Lun; Wan, Xiaohua; Sun, Fei; Zhang, Fa

    2017-01-01

    Electron tomography (ET) plays an important role in studying in situ cell ultrastructure in three-dimensional space. Due to limited tilt angles, ET reconstruction always suffers from the "missing wedge" problem. With a validation procedure, iterative compressed-sensing optimized NUFFT reconstruction (ICON) demonstrates its power in the restoration of validated missing information for low SNR biological ET dataset. However, the huge computational demand has become a major problem for the application of ICON. In this work, we analyzed the framework of ICON and classified the operations of major steps of ICON reconstruction into three types. Accordingly, we designed parallel strategies and implemented them on graphics processing units (GPU) to generate a parallel program ICON-GPU. With high accuracy, ICON-GPU has a great acceleration compared to its CPU version, up to 83.7×, greatly relieving ICON's dependence on computing resource.

  7. Iraq: Reconstruction Assistance

    Science.gov (United States)

    2008-05-22

    Effectiveness..., October 18, 2007, p. x. 51 Shawn Dorman, “Iraq PRTs: Pins on a Map,” Foreign Service Journal, March 2007; Testimony of Ginger Cruz, Deputy... Blood Money, Little, Brown, and Company, 2006; SIGIR, Iraq Reconstruction: Lessons in Program and Project Management, March 2007; and Glenn Zorpette...local participation that would have made projects more effective. Among widely circulated reasons were a failure to anticipate post-invasion security

  8. Reconstructing relational information.

    Science.gov (United States)

    Horecka, Kevin M; Dulas, Michael R; Schwarb, Hillary; Lucas, Heather D; Duff, Melissa; Cohen, Neal J

    2018-02-01

    Hippocampal involvement in learning and remembering relational information has an extensive history, often focusing specifically on spatial information. In humans, spatial reconstruction (SR) paradigms are a powerful tool for evaluating an individuals' spatial-relational memory. In SR tasks, participants study locations of items in space and subsequently reconstruct the studied display after a short delay. Previous work has revealed that patients with hippocampal damage are impaired both in overall placement accuracy as well as on a specific measure of relational memory efficacy, "swaps" (i.e., when the relative location of two items is reversed). However, the necessity of the hippocampus for other types of spatial-relational information involved in reconstruction behaviors (e.g., where in the environment and relative to which other items an item was located) have not yet been investigated systematically. In this work, three patients with hippocampal damage and nine healthy matched comparison participants performed an SR task. An analysis framework was developed to independently assess three first-order types of relations: (1) memory for the binding of specific item identities to locations, (2) memory for arrangement of items in relation to each other or the environment bounds, regardless of memory for the item identity, and (3) higher-order, compound relational errors (i.e., errors involving multiple pieces of relational information). Reconstruction errors were evaluated to determine the degree to which patients and comparisons differed (or not) on each type of spatial-relational information. Data revealed that the primary group difference in performance was for identity-location information. However, when the locations of items were evaluated without regarding the identities, no group difference was found in the number of item placements to studied locations. The present work provides a principled approach to analysis of SR data and clarifies our understanding of

  9. Breast reconstruction and post-mastectomy radiation practice.

    Science.gov (United States)

    Chen, Susie A; Hiley, Crispin; Nickleach, Dana; Petsuksiri, Janjira; Andic, Fundagul; Riesterer, Oliver; Switchenko, Jeffrey M; Torres, Mylin A

    2013-03-02

    The goal of this study was to explore the perspectives and practice of radiation oncologists who treat breast cancer patients who have had breast reconstruction. In 2010, an original electronic survey was sent to all physician members of the American Society of Radiation Oncology, National Cancer Research Institute-Breast Cancer Studies Group in the United Kingdom, Thai Society of Therapeutic Radiology and Oncology, Swiss Society of Radiation Oncology, and Turkish Radiation Oncology Society. We identified factors associated with radiation oncologists who treat breast cancer patients with reconstruction performed prior to radiation and obtained information regarding radiation management of the breast reconstruction. 358 radiation oncologists responded, and 60% of the physicians were from the United States. While 64% of participants agree or strongly agree that breast image affects a woman's quality of life during radiation, 57% feel that reconstruction challenges their ability to deliver effective breast radiation. Compared with other countries, treatment within the United States was associated with a high reconstruction rate (>/= 50% of mastectomy patients) prior to radiation (p clinic patients (p practice is evident from our study of radiation treatment for breast cancer patients with reconstruction. Further research on the impact and delivery of radiation to a reconstructed breast may validate some of the observed practices, highlight the variability in treatment practice, and help create a treatment consensus.

  10. Surreal aroma's. (Reconstructing the volatile heritage of Marcel Duchamp

    Directory of Open Access Journals (Sweden)

    Caro Verbeek

    2016-06-01

    Full Text Available No ‘visual’ artist addressed the sense of smell as often as Marcel Duchamp did. Whereas his solid objects can still be studied visually and textually, the scents he used have by now evaporated, and a vocabulary to describe them is lacking until today. What we have left are nose witness reports and the possibility to smell olfactory reconstructions. Rereading canonical text with a more sensory gaze and inhaling these historical fragrances, such as cedar, erotic perfumes and coffee,  will enable us to reconstruct the olfactory dimension of our highly ocularcentric history of art.

  11. ATLAS Muon Reconstruction Efficiency

    CERN Document Server

    Spearman, W; The ATLAS collaboration

    2012-01-01

    In 2012 the LHC will be operated in a mode leading to up to 40 inelastic pp collisions per bunch crossing, so-called "pile-up". The reconstruction and identification of muons produced in a hard collisions is difficult in this challenging environment. Di-muon decays of J/ψ mesons and Z bosons have been used to study the muon reconstruction and identification efficiency of the ATLAS detector as a function of the muon transverse momentum from pT=4 GeV to pT=100 GeV and the number of inelastic collisions per event. The results show a steep efficiency turn-on curve reaching its plateau value of 100% at pT ~ 6 GeV and no dependence of the muon reconstruction efficiency on the amount pile-up. The studies also reveal that the use of inner detector tracks allows us to distinguish between isolated muons and non-isolated muons produced in jets with high separation power even at the highest pile-up levels.

  12. An open-source, self-explanatory touch screen in routine care. Validity of filling in the Bath measures on Ankylosing Spondylitis Disease Activity Index, Function Index, the Health Assessment Questionnaire and Visual Analogue Scales in comparison with paper versions

    DEFF Research Database (Denmark)

    Schefte, David B; Hetland, Merete L

    2010-01-01

    The Danish DANBIO registry has developed open-source software for touch screens in the waiting room. The objective was to assess the validity of outcomes from self-explanatory patient questionnaires on touch screen in comparison with the traditional paper form in routine clinical care.......The Danish DANBIO registry has developed open-source software for touch screens in the waiting room. The objective was to assess the validity of outcomes from self-explanatory patient questionnaires on touch screen in comparison with the traditional paper form in routine clinical care....

  13. Computing autocatalytic sets to unravel inconsistencies in metabolic network reconstructions

    DEFF Research Database (Denmark)

    Schmidt, R.; Waschina, S.; Boettger-Schmidt, D.

    2015-01-01

    by inherent inconsistencies and gaps. RESULTS: Here we present a novel method to validate metabolic network reconstructions based on the concept of autocatalytic sets. Autocatalytic sets correspond to collections of metabolites that, besides enzymes and a growth medium, are required to produce all biomass...

  14. Pore REconstruction and Segmentation (PORES) method for improved porosity quantification of nanoporous materials

    Energy Technology Data Exchange (ETDEWEB)

    Van Eyndhoven, G., E-mail: geert.vaneyndhoven@uantwerpen.be [iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk (Belgium); Kurttepeli, M. [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Van Oers, C.J.; Cool, P. [Laboratory of Adsorption and Catalysis, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk (Belgium); Bals, S. [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Batenburg, K.J. [iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk (Belgium); Centrum Wiskunde and Informatica, Science Park 123, NL-1090 GB Amsterdam (Netherlands); Mathematical Institute, Universiteit Leiden, Niels Bohrweg 1, NL-2333 CA Leiden (Netherlands); Sijbers, J. [iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk (Belgium)

    2015-01-15

    Electron tomography is currently a versatile tool to investigate the connection between the structure and properties of nanomaterials. However, a quantitative interpretation of electron tomography results is still far from straightforward. Especially accurate quantification of pore-space is hampered by artifacts introduced in all steps of the processing chain, i.e., acquisition, reconstruction, segmentation and quantification. Furthermore, most common approaches require subjective manual user input. In this paper, the PORES algorithm “POre REconstruction and Segmentation” is introduced; it is a tailor-made, integral approach, for the reconstruction, segmentation, and quantification of porous nanomaterials. The PORES processing chain starts by calculating a reconstruction with a nanoporous-specific reconstruction algorithm: the Simultaneous Update of Pore Pixels by iterative REconstruction and Simple Segmentation algorithm (SUPPRESS). It classifies the interior region to the pores during reconstruction, while reconstructing the remaining region by reducing the error with respect to the acquired electron microscopy data. The SUPPRESS reconstruction can be directly plugged into the remaining processing chain of the PORES algorithm, resulting in accurate individual pore quantification and full sample pore statistics. The proposed approach was extensively validated on both simulated and experimental data, indicating its ability to generate accurate statistics of nanoporous materials. - Highlights: • An electron tomography reconstruction/segmentation method for nanoporous materials. • The method exploits the porous nature of the scanned material. • Validated extensively on both simulation and real data experiments. • Results in increased image resolution and improved porosity quantification.

  15. Visual analytics in scalable visualization environments

    OpenAIRE

    Yamaoka, So

    2011-01-01

    Visual analytics is an interdisciplinary field that facilitates the analysis of the large volume of data through interactive visual interface. This dissertation focuses on the development of visual analytics techniques in scalable visualization environments. These scalable visualization environments offer a high-resolution, integrated virtual space, as well as a wide-open physical space that affords collaborative user interaction. At the same time, the sheer scale of these environments poses ...

  16. Reconstruction of the perineum.

    Science.gov (United States)

    Wong, David Sau-Yan

    2014-09-01

    The pelvic and perineal regions are affected by a heterogeneous spectrum of pathologies, many with a tendency to recur. Extensive mutilation carries physical, sexual, and psychological sequelae. Primary reconstruction reduces morbidity and shortens recovery. Modern management calls for a multidisciplinary approach. Not uncommonly, patients come with previous surgery and/or chemoirradiation. They may also be elderly and debilitated. The literature on reconstruction of the perineum can be confusing because knowledge has evolved by an accumulation of isolated short reports of individual methods. This led to the lack of a unifying basis for nomenclature and a failure to relate specific techniques to their roles in repairing particular types of defects. This article gives an overall summary of the approaches in a structured and rational manner. Defects of the external pelvis and perineal lining are usually amenable to coverage with local or regional fasciocutaneous flaps, if primary closure or skin graft is not appropriate. These flaps depend on the integrity of the vascular territories of the internal pudendal, the upper medial thigh plexus, or the descending branches of the inferior gluteal. The location and extent of the resection usually determine the requirements of the reconstruction and may dictate the choice of options. When defects are pelviperineal, particularly when the vagina needs to be reconstructed, myocutaneous flaps are of proven advantage in dealing with both the resurfacing as well as providing the bulk needed to fill the pelvic cavity after extensive resections. The rectus, gluteus, and gracilis are the best known options. Owing to the intrinsic limitations with the gracilis flap, the rectus and gluteus flaps have largely superseded its role in most situations. The rectus flap, in particular, provides good bulk as well as reliable skin. The use of muscle sparing flaps based on the perforator principle in suitable instances has increasingly been

  17. Visualization rhetoric: framing effects in narrative visualization.

    Science.gov (United States)

    Hullman, Jessica; Diakopoulos, Nicholas

    2011-12-01

    Narrative visualizations combine conventions of communicative and exploratory information visualization to convey an intended story. We demonstrate visualization rhetoric as an analytical framework for understanding how design techniques that prioritize particular interpretations in visualizations that "tell a story" can significantly affect end-user interpretation. We draw a parallel between narrative visualization interpretation and evidence from framing studies in political messaging, decision-making, and literary studies. Devices for understanding the rhetorical nature of narrative information visualizations are presented, informed by the rigorous application of concepts from critical theory, semiotics, journalism, and political theory. We draw attention to how design tactics represent additions or omissions of information at various levels-the data, visual representation, textual annotations, and interactivity-and how visualizations denote and connote phenomena with reference to unstated viewing conventions and codes. Classes of rhetorical techniques identified via a systematic analysis of recent narrative visualizations are presented, and characterized according to their rhetorical contribution to the visualization. We describe how designers and researchers can benefit from the potentially positive aspects of visualization rhetoric in designing engaging, layered narrative visualizations and how our framework can shed light on how a visualization design prioritizes specific interpretations. We identify areas where future inquiry into visualization rhetoric can improve understanding of visualization interpretation. © 2011 IEEE

  18. An open-source, self-explanatory touch screen in routine care. Validity of filling in the Bath measures on Ankylosing Spondylitis Disease Activity Index, Function Index, the Health Assessment Questionnaire and Visual Analogue Scales in comparison with paper versions

    DEFF Research Database (Denmark)

    Schefte, David B; Hetland, Merete L

    2010-01-01

    The Danish DANBIO registry has developed open-source software for touch screens in the waiting room. The objective was to assess the validity of outcomes from self-explanatory patient questionnaires on touch screen in comparison with the traditional paper form in routine clinical care....

  19. Image reconstruction in an electro-holographic display

    Science.gov (United States)

    Son, Jung-Young; Son, Wook-Ho; Kim, Jae-Han; Choo, Hyongon

    2017-05-01

    The optical phenomena arising in the process of forming reconstructed images in a hologram are explained and shown visually with the use of light field images. The light fields at different distances from the hologram on a DMD reveal that the reconstructed image of each object point is formed by the corresponding Fresnel zone pattern, which is reconstructed from the hologram when it is illuminated by a reconstruction laser beam. The reconstructed image is a circle of least confusion laden with noise and distortion. It has a finite size and does not appear at the object distance from the hologram due to the presence of aberrations, especially that of a strong astigmatism. The astigmatism