WorldWideScience

Sample records for rapid image acquisition

  1. Rapid Acquisition Imaging Spectrograph (RAISE) Renewal Proposal Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The optical design of RAISE is based on a new class of UV/EUV imaging spectrometers that use  only two reflections to provide quasi-stigmatic performance...

  2. Amplitudes, acquisition and imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bloor, Robert

    1998-12-31

    Accurate seismic amplitude information is important for the successful evaluation of many prospects and the importance of such amplitude information is increasing with the advent of time lapse seismic techniques. It is now widely accepted that the proper treatment of amplitudes requires seismic imaging in the form of either time or depth migration. A key factor in seismic imaging is the spatial sampling of the data and its relationship to the imaging algorithms. This presentation demonstrates that acquisition caused spatial sampling irregularity can affect the seismic imaging and perturb amplitudes. Equalization helps to balance the amplitudes, and the dealing strategy improves the imaging further when there are azimuth variations. Equalization and dealiasing can also help with the acquisition irregularities caused by shot and receiver dislocation or missing traces. 2 refs., 2 figs.

  3. JIEDDO Experience Provides Rapid Acquisition Insights

    National Research Council Canada - National Science Library

    James P Craft

    2015-01-01

    .... JIDA's rapid acquisition capabilities were preserved by transitioning the expedient organization that received supplemental funding into the Defense Department's newest combat support agency (CSA...

  4. Utilizing Information Technology to Facilitate Rapid Acquisition

    Science.gov (United States)

    2006-06-01

    ordering systems to facilitate streamlined commercial item acquisitions that reap the benefits of improved efficiency, reduced overall costs, and...PAGES 109 14. SUBJECT TERMS Rapid Acquisition, eCommerce , eProcurement, Information Technology, Contracting, Global Information Network...streamlined commercial item acquisitions that reap the benefits of improved efficiency, reduced overall costs, and timeliness. This thesis

  5. Rapid Automatic Lighting Control of a Mixed Light Source for Image Acquisition using Derivative Optimum Search Methods

    Directory of Open Access Journals (Sweden)

    Kim HyungTae

    2015-01-01

    Full Text Available Automatic lighting (auto-lighting is a function that maximizes the image quality of a vision inspection system by adjusting the light intensity and color.In most inspection systems, a single color light source is used, and an equal step search is employed to determine the maximum image quality. However, when a mixed light source is used, the number of iterations becomes large, and therefore, a rapid search method must be applied to reduce their number. Derivative optimum search methods follow the tangential direction of a function and are usually faster than other methods. In this study, multi-dimensional forms of derivative optimum search methods are applied to obtain the maximum image quality considering a mixed-light source. The auto-lighting algorithms were derived from the steepest descent and conjugate gradient methods, which have N-size inputs of driving voltage and one output of image quality. Experiments in which the proposed algorithm was applied to semiconductor patterns showed that a reduced number of iterations is required to determine the locally maximized image quality.

  6. Prospector: A web-based tool for rapid acquisition of gold standard data for pathology research and image analysis

    Directory of Open Access Journals (Sweden)

    Alexander I Wright

    2015-01-01

    Full Text Available Background: Obtaining ground truth for pathological images is essential for various experiments, especially for training and testing image analysis algorithms. However, obtaining pathologist input is often difficult, time consuming and expensive. This leads to algorithms being over-fitted to small datasets, and inappropriate validation, which causes poor performance on real world data. There is a great need to gather data from pathologists in a simple and efficient manner, in order to maximise the amount of data obtained. Methods: We present a lightweight, web-based HTML5 system for administering and participating in data collection experiments. The system is designed for rapid input with minimal effort, and can be accessed from anywhere in the world with a reliable internet connection. Results: We present two case studies that use the system to assess how limitations on fields of view affect pathologist agreement, and to what extent poorly stained slides affect judgement. In both cases, the system collects pathologist scores at a rate of less than two seconds per image. Conclusions: The system has multiple potential applications in pathology and other domains.

  7. Rapid acquisition of helium-3 and proton three-dimensional image sets of the human lung in a single breath-hold using compressed sensing.

    Science.gov (United States)

    Qing, Kun; Altes, Talissa A; Tustison, Nicholas J; Feng, Xue; Chen, Xiao; Mata, Jaime F; Miller, G Wilson; de Lange, Eduard E; Tobias, William A; Cates, Gordon D; Brookeman, James R; Mugler, John P

    2015-10-01

    To develop and validate a method for acquiring helium-3 ((3) He) and proton ((1) H) three-dimensional (3D) image sets of the human lung with isotropic spatial resolution within a 10-s breath-hold by using compressed sensing (CS) acceleration, and to assess the fidelity of undersampled images compared with fully sampled images. The undersampling scheme for CS acceleration was optimized and tested using (3) He ventilation data. Rapid 3D acquisition of both (3) He and (1) H data during one breath-hold was then implemented, based on a balanced steady-state free-precession pulse sequence, by random undersampling of k-space with reconstruction by means of minimizing the L1 norm and total variance. CS-reconstruction fidelity was evaluated quantitatively by comparing fully sampled and retrospectively undersampled image sets. Helium-3 and (1) H 3D image sets of the lung with isotropic 3.9-mm resolution were acquired during a single breath-hold in 12 s and 8 s using acceleration factors of 2 and 3, respectively. Comparison of fully sampled and retrospectively undersampled (3) He and (1) H images yielded mean absolute errors 0.9. By randomly undersampling k-space and using CS reconstruction, high-quality (3) He and (1) H 3D image sets with isotropic 3.9-mm resolution can be acquired within an 8-s breath-hold. © 2014 Wiley Periodicals, Inc.

  8. MR sequences and rapid acquisition for MR guided interventions

    Science.gov (United States)

    Campbell-Washburn, Adrienne E; Faranesh, Anthony Z; Lederman, Robert J; Hansen, Michael S

    2015-01-01

    Synopsis Interventional MR uses rapid imaging to guide diagnostic and therapeutic procedures. One of the attractions of MR-guidance is the abundance of inherent contrast mechanisms available. Dynamic procedural guidance with real-time imaging has pushed the limits of MR technology, demanding rapid acquisition and reconstruction paired with interactive control and device visualization. This article reviews the technical aspects of real-time MR sequences that enable MR-guided interventions. PMID:26499283

  9. Organizational Design for USSOCOM Rapid Acquisition

    Science.gov (United States)

    2017-03-31

    2 Ibid., 249. 25 of the programs.3 In rapid innovation , it is important for Program Executive Officers to ensure that technical...organizational learning is what the company does in order to create innovative products and survive. They note that, “interviewees emphasized the importance ...14. ABSTRACT USSOCOM Special Operations Forces (SOF) Acquisition, Technology and Logistics (AT&L) struggles to keep pace with technology innovation

  10. Literacy acquisition influences children's rapid automatized naming.

    Science.gov (United States)

    Peterson, Robin L; Arnett, Anne B; Pennington, Bruce F; Byrne, Brian; Samuelsson, Stefan; Olson, Richard K

    2017-08-15

    Previous research has established that learning to read improves children's performance on reading-related phonological tasks, including phoneme awareness (PA) and nonword repetition. Few studies have investigated whether literacy acquisition also promotes children's rapid automatized naming (RAN). We tested the hypothesis that literacy acquisition should influence RAN in an international, longitudinal population sample of twins. Cross-lagged path models evaluated the relationships among literacy, PA, and RAN across four time points from pre-kindergarten through grade 4. Consistent with previous research, literacy showed bidirectional relationships with reading-related oral language skills. We found novel evidence for an effect of earlier literacy on later RAN, which was most evident in children at early phases of literacy development. In contrast, the influence of earlier RAN on later literacy was predominant among older children. These findings imply that the association between these two related skills is moderated by development. Implications for models of reading development and for dyslexia research are discussed. © 2017 John Wiley & Sons Ltd.

  11. Analysis of Rapid Acquisition Processes to Fulfill Future Urgent Needs

    Science.gov (United States)

    2015-12-01

    UAVs , the DOD defines UAVs as “powered aerial vehicle that does not carry a human operator; use aerodynamic forces to provide lift; can be autonomously...25 B. UAV ...25 1. UAV Background ...............................................................................25 2. Rapid Acquisition in UAV

  12. SPRAT: Spectrograph for the Rapid Acquisition of Transients

    Science.gov (United States)

    Piascik, A. S.; Steele, Iain A.; Bates, Stuart D.; Mottram, Christopher J.; Smith, R. J.; Barnsley, R. M.; Bolton, B.

    2014-07-01

    We describe the development of a low cost, low resolution (R ~ 350), high throughput, long slit spectrograph covering visible (4000-8000) wavelengths. The spectrograph has been developed for fully robotic operation with the Liverpool Telescope (La Palma). The primary aim is to provide rapid spectral classification of faint (V ˜ 20) transient objects detected by projects such as Gaia, iPTF (intermediate Palomar Transient Factory), LOFAR, and a variety of high energy satellites. The design employs a volume phase holographic (VPH) transmission grating as the dispersive element combined with a prism pair (grism) in a linear optical path. One of two peak spectral sensitivities are selectable by rotating the grism. The VPH and prism combination and entrance slit are deployable, and when removed from the beam allow the collimator/camera pair to re-image the target field onto the detector. This mode of operation provides automatic acquisition of the target onto the slit prior to spectrographic observation through World Coordinate System fitting. The selection and characterisation of optical components to maximise photon throughput is described together with performance predictions.

  13. Effective GPR Data Acquisition and Imaging

    Science.gov (United States)

    Sato, M.

    2014-12-01

    We have demonstrated that dense GPR data acquisition typically antenna step increment less than 1/10 wave length can provide clear 3-dimeantiona subsurface images, and we created 3DGPR images. Now we are interested in developing GPR survey methodologies which required less data acquisition time. In order to speed up the data acquisition, we are studying efficient antenna positioning for GPR survey and 3-D imaging algorithm. For example, we have developed a dual sensor "ALIS", which combines GPR with metal detector (Electromagnetic Induction sensor) for humanitarian demining, which acquires GPR data by hand scanning. ALIS is a pulse radar system, which has a frequency range 0.5-3GHz.The sensor position tracking system has accuracy about a few cm, and the data spacing is typically more than a few cm, but it can visualize the mines, which has a diameter about 8cm. 2 systems of ALIS have been deployed by Cambodian Mine Action Center (CMAC) in mine fields in Cambodia since 2009 and have detected more than 80 buried land mines. We are now developing signal processing for an array type GPR "Yakumo". Yakumo is a SFCW radar system which is a multi-static radar, consisted of 8 transmitter antennas and 8 receiver antennas. We have demonstrated that the multi-static data acquisition is not only effective in data acquisition, but at the same time, it can increase the quality of GPR images. Archaeological survey by Yakumo in large areas, which are more than 100m by 100m have been conducted, for promoting recovery from Tsunami attacked East Japan in March 2011. With a conventional GPR system, we are developing an interpolation method of radar signals, and demonstrated that it can increase the quality of the radar images, without increasing the data acquisition points. When we acquire one dimensional GPR profile along a survey line, we can acquire relatively high density data sets. However, when we need to relocate the data sets along a "virtual" survey line, for example a

  14. Rapid chemical shift encoding with single-acquisition single-slab 3D GRASE.

    Science.gov (United States)

    Kim, Hahnsung; Kim, Dong-Hyun; Sohn, Chul-Ho; Park, Jaeseok

    2017-11-01

    To investigate the feasibility of chemical shift encoded, single-slab 3D GRASE for rapid fat-water separation within a single acquisition. The proposed method incorporates signal-to-noise-ratio-optimal chemical shift encoding into single-slab 3D GRASE with variable flip angles. Chemical shift induced phase information was encoded in succession to different positions in k-space by inserting phase encoding blips between adjacent lobes of the oscillating readout gradients. To enhance imaging efficiency, signal prescription-based variable flip angles were used in the long refocusing pulse train. After echo-independent phase correction, missing signals in k-echo space were interpolated using convolution kernels that span over all echoes. Fat-water separation in a single acquisition was performed using both multi-echo fast spin echo and GRASE as compared to conventional multiacquisition fast spin echo with echo shifts. The proposed single-slab 3D GRASE shows superior performance in accurately delineating cartilage structures compared to its counterpart, multi-echo 3D fast spin echo. Compared with multiacquisition fast spin echo with three echo shifts (63 min), the proposed method substantially speeds up imaging time (7 min), and achieves 0.6 mm isotropic resolution in knee imaging with reduced artifacts and noise. We successfully demonstrated the feasibility of rapid chemical shift encoding and separation using the proposed, single-acquisition single-slab 3D GRASE for high resolution isotropic imaging within clinically acceptable time. Magn Reson Med 78:1852-1861, 2017. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  15. Reproducible high-resolution multispectral image acquisition in dermatology

    Science.gov (United States)

    Duliu, Alexandru; Gardiazabal, José; Lasser, Tobias; Navab, Nassir

    2015-07-01

    Multispectral image acquisitions are increasingly popular in dermatology, due to their improved spectral resolution which enables better tissue discrimination. Most applications however focus on restricted regions of interest, imaging only small lesions. In this work we present and discuss an imaging framework for high-resolution multispectral imaging on large regions of interest.

  16. Shuffled magnetization-prepared multicontrast rapid gradient-echo imaging.

    Science.gov (United States)

    Cao, Peng; Zhu, Xucheng; Tang, Shuyu; Leynes, Andrew; Jakary, Angela; Larson, Peder E Z

    2018-01-01

    To develop a novel acquisition and reconstruction method for magnetization-prepared 3-dimensional multicontrast rapid gradient-echo imaging, using Hankel matrix completion in combination with compressed sensing and parallel imaging. A random k-space shuffling strategy was implemented in simulation and in vivo human experiments at 7 T for 3-dimensional inversion recovery, T2 /diffusion preparation, and magnetization transfer imaging. We combined compressed sensing, based on total variation and spatial-temporal low-rank regularizations, and parallel imaging with pixel-wise Hankel matrix completion, allowing the reconstruction of tens of multicontrast 3-dimensional images from 3- or 6-min scans. The simulation result showed that the proposed method can reconstruct signal-recovery curves in each voxel and was robust for typical in vivo signal-to-noise ratio with 16-times acceleration. In vivo studies achieved 4 to 24 times accelerations for inversion recovery, T2 /diffusion preparation, and magnetization transfer imaging. Furthermore, the contrast was improved by resolving pixel-wise signal-recovery curves after magnetization preparation. The proposed method can improve acquisition efficiencies for magnetization-prepared MRI and tens of multicontrast 3-dimensional images could be recovered from a single scan. Furthermore, it was robust against noise, applicable for recovering multi-exponential signals, and did not require any previous knowledge of model parameters. Magn Reson Med 79:62-70, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  17. Rapid seismic reflection imaging in an urban environment

    Science.gov (United States)

    Liberty, L. M.

    2011-12-01

    Subsurface characterization in urban areas is important for city planners, municipalities, and engineers to estimate groundwater resources, track contaminants, assess earthquake or landslide hazards, and many other similar objectives. Improving geophysical imaging methods and results, while minimizing costs, provides greater opportunities for city/project planners and geophysicists alike to take advantage of the improved characterization afforded by the particular method. Seismic reflection results can provide hydrogeologic constraints for groundwater models, provide slip rate estimates for active faults, or simply map stratigraphy to provide target depth estimates. While many traditional urban seismic transects have included the use of vibroseis sources to improve reflection signals and attenuate cultural noise, low cost and high quality near-surface seismic reflection data can be obtained within an urban environment using impulsive sources at a variety of scales and at production rates that can significantly exceed those of swept sources. Sledgehammers and hydraulically powered accelerated weight drops allow rapid acquisition rates through dense urban corridors where the objective is to image targets in the upper one km depth range. In addition permit and land access issues; culturally noisy urban environments can provide additional challenges to producing high quality seismic reflection results. Acquisition methods designed to address both coherent and random noises include recording redundant, unstacked, unfiltered field records. Processing steps that improve data quality in this setting include diversity stacking to attenuate large-amplitude coherent (non-repeatable) vehicle noise and subtraction of power line signals via match filters to retain reflection signals near alternating current frequencies. These acquisition and processing approaches allow for rapid and low cost data acquisition at the expense of moderately increased computing time and disk space. I

  18. An Analysis of Test And Evaluation in Rapid Acquisition Programs

    Science.gov (United States)

    2015-12-01

    Outfits DT Developmental Testing DT&E Development Test and Evaluation DTC Developmental Test Command E3 Electromagnetic Environmental Effects...by the OEM and evaluated by the Communication-Electronics Command (CECOM) Safety Office and the former Developmental Test Command ( DTC ) covering all...Force Management School AMC Army Materiel Command AOA Analysis of Alternatives AOR Area of Operation APC Acquisition Program Candidates APG Aberdeen

  19. High speed image acquisition system of absolute encoder

    Science.gov (United States)

    Liao, Jianxiang; Chen, Xin; Chen, Xindu; Zhang, Fangjian; Wang, Han

    2017-01-01

    Absolute optical encoder as a product of optical, mechanical and electronic integration has been widely used in displacement measuring fields. However, how to improve the measurement velocity and reduce the manufacturing cost of absolute optical encoder is the key problem to be solved. To improve the measurement speed, a novel absolute optical encoder image acquisition system is proposed. The proposed acquisition system includes a linear CCD sensor is applied for capturing coding pattern images, an optical magnifying system is used for enlarging the grating stripes, an analog-digital conversion(ADC) module is used for processing the CCD analogy signal, a field programmable gate array(FPGA) device and other peripherals perform driving task. An absolute position measurement experiment was set up to verify and evaluate the proposed image acquisition system. The experimental result indicates that the proposed absolute optical encoder image acquisition system has the image acquisition speed of more than 9500fp/s with well reliability and lower manufacture cost.

  20. Rapid MR spectroscopic imaging of lactate using compressed sensing

    Science.gov (United States)

    Vidya Shankar, Rohini; Agarwal, Shubhangi; Geethanath, Sairam; Kodibagkar, Vikram D.

    2015-03-01

    Imaging lactate metabolism in vivo may improve cancer targeting and therapeutics due to its key role in the development, maintenance, and metastasis of cancer. The long acquisition times associated with magnetic resonance spectroscopic imaging (MRSI), which is a useful technique for assessing metabolic concentrations, are a deterrent to its routine clinical use. The objective of this study was to combine spectral editing and prospective compressed sensing (CS) acquisitions to enable precise and high-speed imaging of the lactate resonance. A MRSI pulse sequence with two key modifications was developed: (1) spectral editing components for selective detection of lactate, and (2) a variable density sampling mask for pseudo-random under-sampling of the k-space `on the fly'. The developed sequence was tested on phantoms and in vivo in rodent models of cancer. Datasets corresponding to the 1X (fully-sampled), 2X, 3X, 4X, 5X, and 10X accelerations were acquired. The under-sampled datasets were reconstructed using a custom-built algorithm in MatlabTM, and the fidelity of the CS reconstructions was assessed in terms of the peak amplitudes, SNR, and total acquisition time. The accelerated reconstructions demonstrate a reduction in the scan time by up to 90% in vitro and up to 80% in vivo, with negligible loss of information when compared with the fully-sampled dataset. The proposed unique combination of spectral editing and CS facilitated rapid mapping of the spatial distribution of lactate at high temporal resolution. This technique could potentially be translated to the clinic for the routine assessment of lactate changes in solid tumors.

  1. Efficient Lossy Compression for Compressive Sensing Acquisition of Images in Compressive Sensing Imaging Systems

    Directory of Open Access Journals (Sweden)

    Xiangwei Li

    2014-12-01

    Full Text Available Compressive Sensing Imaging (CSI is a new framework for image acquisition, which enables the simultaneous acquisition and compression of a scene. Since the characteristics of Compressive Sensing (CS acquisition are very different from traditional image acquisition, the general image compression solution may not work well. In this paper, we propose an efficient lossy compression solution for CS acquisition of images by considering the distinctive features of the CSI. First, we design an adaptive compressive sensing acquisition method for images according to the sampling rate, which could achieve better CS reconstruction quality for the acquired image. Second, we develop a universal quantization for the obtained CS measurements from CS acquisition without knowing any a priori information about the captured image. Finally, we apply these two methods in the CSI system for efficient lossy compression of CS acquisition. Simulation results demonstrate that the proposed solution improves the rate-distortion performance by 0.4~2 dB comparing with current state-of-the-art, while maintaining a low computational complexity.

  2. Acquisition and performance of the Star Imager

    DEFF Research Database (Denmark)

    Jørgensen, John Leif

    1997-01-01

    The Star Imager performance under various ground-based operating conditions is discussed. The precision is generally found to be in the range of 1 arcsecond 1 pointing and 5 to 8 times larger for the measured roll about the boresight. Even though a carefully planned and conducted test series has...... been performed, the systematic errors and test-setup related biases and noise sources seem to dominate the measurements. The instrument is then expected to show a better performance in space. Particular emphasis has been directed towards the performance of the software when exposed to images acquired...... of the Star Imager may be extended to 5-6 deg/sec, as demonstrated by the "Thunderstorm III" flight data, or by decreasing the integration time, as for the ASTRID II micro satellite version of the instrument, expected to operate at rates up to 18 degrees per second....

  3. Is Sordac’s Rapid Acquisition Process Best Prepared To Field Solutions For Future Technological Challenges

    Science.gov (United States)

    2016-03-31

    views expressed in this academic research paper are those of the author and do not reflect the official policy or position of the US government, the...SORDAC) is the Department of Defense (DoD) leader in rapid acquisitions, and its culture and practices should be benchmarked by the other services. This...should be benchmarked by all other services. This essay first examines SORDAC’s acquisition environment and assesses SORDAC’s unique culture. This

  4. Influence of acquisition parameters on MV-CBCT image quality.

    Science.gov (United States)

    Gayou, Olivier

    2012-01-05

    The production of high quality pretreatment images plays an increasing role in image-guided radiotherapy (IGRT) and adaptive radiation therapy (ART). Megavoltage cone-beam computed tomography (MV-CBCT) is the simplest solution of all the commercially available volumetric imaging systems for localization. It also suffers the most from relatively poor contrast due to the energy range of the imaging photons. Several avenues can be investigated to improve MV-CBCT image quality while maintaining an acceptable patient exposure: beam generation, detector technology, reconstruction parameters, and acquisition parameters. This article presents a study of the effects of the acquisition scan length and number of projections of a Siemens Artiste MV-CBCT system on image quality within the range provided by the manufacturer. It also discusses other aspects not related to image quality one should consider when selecting an acquisition protocol. Noise and uniformity were measured on the image of a cylindrical water phantom. Spatial resolution was measured using the same phantom half filled with water to provide a sharp water/air interface to derive the modulation transfer function (MTF). Contrast-to-noise ratio (CNR) was measured on a pelvis-shaped phantom with four inserts of different electron densities relative to water (1.043, 1.117, 1.513, and 0.459). Uniformity was independent of acquisition protocol. Noise decreased from 1.96% to 1.64% when the total number of projections was increased from 100 to 600 for a total exposure of 13.5 MU. The CNR showed a ± 5% dependence on the number of projections and 10% dependence on the scan length. However, these variations were not statistically significant. The spatial resolution was unaffected by the arc length or the sampling rate. Acquisition parameters have little to no effect on the image quality of the MV-CBCT system within the range of parameters available on the system. Considerations other than image quality, such as memory

  5. Real-Time Protein Crystallization Image Acquisition and Classification System

    Science.gov (United States)

    Sigdel, Madhav; Pusey, Marc L.; Aygun, Ramazan S.

    2014-01-01

    In this paper, we describe the design and implementation of a stand-alone real-time system for protein crystallization image acquisition and classification with a goal to assist crystallographers in scoring crystallization trials. In-house assembled fluorescence microscopy system is built for image acquisition. The images are classified into three categories as non-crystals, likely leads, and crystals. Image classification consists of two main steps – image feature extraction and application of classification based on multilayer perceptron (MLP) neural networks. Our feature extraction involves applying multiple thresholding techniques, identifying high intensity regions (blobs), and generating intensity and blob features to obtain a 45-dimensional feature vector per image. To reduce the risk of missing crystals, we introduce a max-class ensemble classifier which applies multiple classifiers and chooses the highest score (or class). We performed our experiments on 2250 images consisting 67% non-crystal, 18% likely leads, and 15% clear crystal images and tested our results using 10-fold cross validation. Our results demonstrate that the method is very efficient (< 3 seconds to process and classify an image) and has comparatively high accuracy. Our system only misses 1.2% of the crystals (classified as non-crystals) most likely due to low illumination or out of focus image capture and has an overall accuracy of 88%. PMID:24532991

  6. A digital image acquisition system for skin lesions

    Science.gov (United States)

    Maglogiannis, Ilias G.; Kosmopoulos, Dimitrios I.

    2003-05-01

    A major issue concerning the design and implementation of an acquisition system for digital images of skin lesions is the ability of capturing reproducible images. The reproducibility is considered essential for image analysis classification and for the comparison of sequential images during follow-up studies. This paper describes a complete image acquisition system used for the collection of reproducible images of patients having melanoma and compares them with images displaying dysplastic nevus for diagnostic purposes. The system includes a standardized illumination and capturing geometry with polarizing filters and a series of software corrections: Calibration to Black, White, Internal and External camera parameters, Shading correction and Median filtering. The validity of the calibration procedure and the ability of the implemented system to produce reproducible images were tested by capturing sample images in 3 different lighting conditions of the surrounding environment: dark, medium and intense lighting. For each case the average values of the three-color planes RGB and their standard deviations were calculated and the measured error differences ranged between 0,4 and 13,2 (in the 0-255 scale). Preliminary experiments for stereo measurements provided repeatability of about 0.3mm. The above numbers demonstrate the reproducibility of the captured images at a satisfactory level.

  7. Working Papers in Acquisition of Knowledge for Image Understanding Research,

    Science.gov (United States)

    1976-12-15

    mechanisms useful in generating these transcriptions in the first place. 11. MET1-0D The picture -puzzle paradigm used was human simulation of image ...University, 1975. 18. R. N. Shepard, Recognition memory for words, sentences and pictures , Jornal of Verbal Learning and Verbal Behavior, 6, 1976. 19. D. L...protocols in the picture -puzzle experiment. 29 REFERENCES 1. Akin, 0. and Reddy, R. Knowledge acquisition for image understanding research, Jour~a of

  8. Automatic model acquisition and aerial image understanding

    Science.gov (United States)

    Jaynes, Christopher O.

    This thesis introduces a model-based technique for the automatic recognition and three-dimensional reconstruction of buildings directly from a single range image or stereo processing of multiple optical views of an urban site. Initially, focus-of-attention regions that are likely to contain buildings are segmented from the scene. A perceptual grouping algorithm detects building boundaries as closed polygons in the optical image. When a digital elevation map (DEM) is the only input source available, building regions are detected through direct analysis of the elevation data. Both methods then utilize the key idea of matching a database of shape models against the DEM using a model-indexing procedure that compares orientation histograms for each parameterized model in the database to a histogram that corresponds to the DEM region. The set of models (surfaces) that most closely match the DEM region are used as the initial estimates in a robust surface fitting technique that refines the model parameters (such as orientation and peak-roof angle) of each hypothesized roof surface. The surface model that converges to the DEM with the lowest residual fit error is retained as the most likely description of the surface. The database of surface models contains a limited number of canonical shapes common to rooftops, such as planes, peaks, domes, and gables. Reconstruction of complex shapes is achieved through a composition of different parameterizations of the canonical shape models. We show how the technique can be recursively applied to a range image to segment and reconstruct buildings as well as rooftop substructure. The ability of the model-indexing technique to separate surface models under different resolutions of the parameter space and different levels of noise in the DEM is studied. The approach is evaluated on several datasets, and we demonstrate that this two-phase reconstruction approach allows robust and accurate reconstruction of a wide variety of building

  9. Data acquisition system for a proton imaging apparatus

    CERN Document Server

    Sipala, V; Bruzzi, M; Bucciolini, M; Candiano, G; Capineri, L; Cirrone, G A P; Civinini, C; Cuttone, G; Lo Presti, D; Marrazzo, L; Mazzaglia, E; Menichelli, D; Randazzo, N; Talamonti, C; Tesi, M; Valentini, S

    2009-01-01

    New developments in the proton-therapy field for cancer treatments, leaded Italian physics researchers to realize a proton imaging apparatus consisting of a silicon microstrip tracker to reconstruct the proton trajectories and a calorimeter to measure their residual energy. For clinical requirements, the detectors used and the data acquisition system should be able to sustain about 1 MHz proton rate. The tracker read-out, using an ASICs developed by the collaboration, acquires the signals detector and sends data in parallel to an FPGA. The YAG:Ce calorimeter generates also the global trigger. The data acquisition system and the results obtained in the calibration phase are presented and discussed.

  10. Rapid MR imaging of cryoprotectant permeation in an engineered dermal replacement.

    Science.gov (United States)

    Bidault, N P; Hammer, B E; Hubel, A

    2000-02-01

    Magnetic resonance (MR) imaging is a powerful technique for monitoring the permeation of cryoprotective agents (CPAs) inside tissues. However, the techniques published until now suffer from inherently long imaging times, limiting the application of these techniques to slow diffusion processes and large CPA concentrations. In this study, we present a rapid MR imaging technique based on a CHESS-FLASH scheme combined with Keyhole image acquisition. This technique can image the fast permeation of Me(2)SO solutions into freeze-dried artificial dermal replacements for concentrations down to 10% v/v. Special attention is given to evaluating the technique for quantitative analysis. Copyright 2000 Academic Press.

  11. Rapid Learning of an Abstract Language-Specific Category: Polish Children's Acquisition of the Instrumental Construction

    Science.gov (United States)

    Dabrowska, Ewa; Tomasello, Michael

    2008-01-01

    Rapid acquisition of linguistic categories or constructions is sometimes regarded as evidence of innate knowledge. In this paper, we examine Polish children's early understanding of an idiosyncratic, language-specific construction involving the instrumental case--which could not be due to innate knowledge. Thirty Polish-speaking children aged 2; 6…

  12. Rock fracture image acquisition with both visible and ultraviolet illuminations

    Science.gov (United States)

    Wang, Weixing; Hakami, Eva

    2006-02-01

    Swedish Nuclear Fuel and Waste Management Company (SKB) have identified the need for a better understanding of radionuclide transport and retention processes in fractured rock since 1994. In the study, the first hard problem is to obtain rock fracture images of a good quality, since rock surface is very rough, and composed of complicated and multiple fractures, as a result, image acquisition is the first important. As a cooperation project between Sweden and China, we sampled a number of rock specimens for analyzing rock fracture network by visible and ultraviolet image technique, in the field. The samples are resin injected, in which way; opened fractures can be seen clearly by means of UV light illumination, and the rock surface information can be obtained by using visible optical illumination. We used different digital cameras and microscope to take images by two illuminations. From the same samples; we found that UV illumination image gives the clear information of fracture opening or closing, and the visible optical illumination gives the information of the rock surface (e.g. filling materials inside of fractures). By applying this technique, the minimum width of rock fracture 0.01 mm can be analyzed. This paper presents: (1) Rock fracture image acquiring techniques; (2) Rock fracture image acquisition by using UV light illumination and visible optical illumination; and (3) Conclusions. The studied method can be used both in the field and a laboratory.

  13. Acquisition and Post-Processing of Immunohistochemical Images.

    Science.gov (United States)

    Sedgewick, Jerry

    2017-01-01

    Augmentation of digital images is almost always a necessity in order to obtain a reproduction that matches the appearance of the original. However, that augmentation can mislead if it is done incorrectly and not within reasonable limits. When procedures are in place for insuring that originals are archived, and image manipulation steps reported, scientists not only follow good laboratory practices, but avoid ethical issues associated with post processing, and protect their labs from any future allegations of scientific misconduct. Also, when procedures are in place for correct acquisition of images, the extent of post processing is minimized or eliminated. These procedures include white balancing (for brightfield images), keeping tonal values within the dynamic range of the detector, frame averaging to eliminate noise (typically in fluorescence imaging), use of the highest bit depth when a choice is available, flatfield correction, and archiving of the image in a non-lossy format (not JPEG).When post-processing is necessary, the commonly used applications for correction include Photoshop, and ImageJ, but a free program (GIMP) can also be used. Corrections to images include scaling the bit depth to higher and lower ranges, removing color casts from brightfield images, setting brightness and contrast, reducing color noise, reducing "grainy" noise, conversion of pure colors to grayscale, conversion of grayscale to colors typically used in fluorescence imaging, correction of uneven illumination (flatfield correction), merging color images (fluorescence), and extending the depth of focus. These corrections are explained in step-by-step procedures in the chapter that follows.

  14. Impact of image acquisition timing on image quality for dual energy contrast-enhanced breast tomosynthesis

    Science.gov (United States)

    Hill, Melissa L.; Mainprize, James G.; Puong, Sylvie; Carton, Ann-Katherine; Iordache, Razvan; Muller, Serge; Yaffe, Martin J.

    2012-03-01

    Dual-energy contrast-enhanced digital breast tomosynthesis (DE CE-DBT) image quality is affected by a large parameter space including the tomosynthesis acquisition geometry, imaging technique factors, the choice of reconstruction algorithm, and the subject breast characteristics. The influence of most of these factors on reconstructed image quality is well understood for DBT. However, due to the contrast agent uptake kinetics in CE imaging, the subject breast characteristics change over time, presenting a challenge for optimization . In this work we experimentally evaluate the sensitivity of the reconstructed image quality to timing of the low-energy and high-energy images and changes in iodine concentration during image acquisition. For four contrast uptake patterns, a variety of acquisition protocols were tested with different timing and geometry. The influence of the choice of reconstruction algorithm (SART or FBP) was also assessed. Image quality was evaluated in terms of the lesion signal-difference-to-noise ratio (LSDNR) in the central slice of DE CE-DBT reconstructions. Results suggest that for maximum image quality, the low- and high-energy image acquisitions should be made within one x-ray tube sweep, as separate low- and high-energy tube sweeps can degrade LSDNR. In terms of LSDNR per square-root dose, the image quality is nearly equal between SART reconstructions with 9 and 15 angular views, but using fewer angular views can result in a significant improvement in the quantitative accuracy of the reconstructions due to the shorter imaging time interval.

  15. Free-space laser communication system with rapid acquisition based on astronomical telescopes.

    Science.gov (United States)

    Wang, Jianmin; Lv, Junyi; Zhao, Guang; Wang, Gang

    2015-08-10

    The general structure of a free-space optical (FSO) communication system based on astronomical telescopes is proposed. The light path for astronomical observation and for communication can be easily switched. A separate camera is used as a star sensor to determine the pointing direction of the optical terminal's antenna. The new system exhibits rapid acquisition and is widely applicable in various astronomical telescope systems and wavelengths. We present a detailed analysis of the acquisition time, which can be decreased by one order of magnitude compared with traditional optical communication systems. Furthermore, we verify software algorithms and tracking accuracy.

  16. Compressive Acquisition of Color and Near-Infrared Images

    OpenAIRE

    Sadeghipoor Kermani, Zahra; Lu, Yue; Süsstrunk, Sabine

    2014-01-01

    We propose using a single silicon sensor and a modified Bayer CFA for joint acquisition of color and near-infrared (NIR) images. Silicon sensors, which are placed in most color cameras, are inherently sensitive to NIR. Hence, our proposed design is very similar to consumer color cameras in terms of hardware. The main contribution of this work is an algorithm that estimates full-resolution color and NIR images from subsampled and mixed sensor measurements. Our method results in high-quality RG...

  17. An automated system for whole microscopic image acquisition and analysis.

    Science.gov (United States)

    Bueno, Gloria; Déniz, Oscar; Fernández-Carrobles, María Del Milagro; Vállez, Noelia; Salido, Jesús

    2014-09-01

    The field of anatomic pathology has experienced major changes over the last decade. Virtual microscopy (VM) systems have allowed experts in pathology and other biomedical areas to work in a safer and more collaborative way. VMs are automated systems capable of digitizing microscopic samples that were traditionally examined one by one. The possibility of having digital copies reduces the risk of damaging original samples, and also makes it easier to distribute copies among other pathologists. This article describes the development of an automated high-resolution whole slide imaging (WSI) system tailored to the needs and problems encountered in digital imaging for pathology, from hardware control to the full digitization of samples. The system has been built with an additional digital monochromatic camera together with the color camera by default and LED transmitted illumination (RGB). Monochrome cameras are the preferred method of acquisition for fluorescence microscopy. The system is able to digitize correctly and form large high resolution microscope images for both brightfield and fluorescence. The quality of the digital images has been quantified using three metrics based on sharpness, contrast and focus. It has been proved on 150 tissue samples of brain autopsies, prostate biopsies and lung cytologies, at five magnifications: 2.5×, 10×, 20×, 40×, and 63×. The article is focused on the hardware set-up and the acquisition software, although results of the implemented image processing techniques included in the software and applied to the different tissue samples are also presented. © 2014 Wiley Periodicals, Inc.

  18. Rapid Delivery of Cyber Capabilities: Evaluation of the Requirement for a Rapid Cyber Acquisition Process

    Science.gov (United States)

    2012-06-01

    capabilities and rapid implementation of tactics—all aspects readily addressed using non-material solutions. Additionally, configuration and maintenance of...Offict Symbol: 4. Co~ttac-t 1nror11tation: (l\\’am~ Pj Rcqu.-$1/.Uomtlt’nttNU POC) (RD.11J.!Crrult’) (0/ Jit ’’ Spn) Phone’ 1\\’un.rbo S. T ec:hni<’lll POC 6

  19. The influence of image compression on target acquisition

    Science.gov (United States)

    Hadar, O.; Goldberg, E.; Topchik, E.

    2008-02-01

    With the increased use of multimedia technologies, image compression has become increasingly popular. Compression decreases the high demands for storage capacity and transmission bandwidth. However, when compressing an image, some part of the information is lost, since the compression smoothes high frequencies thereby distorting small details. This issue is crucial, especially in military, spying and medical systems. When planning these kinds of systems, the image compression quality must be considered as well as how it affects the mission performance carried out by the user. Our goal is to examine the behavior of the human eye during image scanning and try to quantify the effect of image compression on observer tasks such as target acquisition. For this task, we used the standard JPEG2000 in order to compress the images at different compression ratios ranging from 10% (the highest) to 100% (the original image). It was found that animation images were more influenced by compression than thermal images. In general, as the compression ratio increased the ability to acquire the targets decreased.

  20. Knowledge acquisition and rapid protyping of an expert system: Dealing with real world problems

    Science.gov (United States)

    Bailey, Patrick A.; Doehr, Brett B.

    1988-01-01

    The knowledge engineering and rapid prototyping phases of an expert system that does fault handling for a Solid Amine, Water Desorbed CO2 removal assembly for the Environmental Control and Life Support System for space based platforms are addressed. The knowledge acquisition phase for this project was interesting because it could not follow the textbook examples. As a result of this, a variety of methods were used during the knowledge acquisition task. The use of rapid prototyping and the need for a flexible prototype suggested certain types of knowledge representation. By combining various techniques, a representative subset of faults and a method for handling those faults was achieved. The experiences should prove useful for developing future fault handling expert systems under similar constraints.

  1. Pediatric imaging. Rapid fire questions and answers

    Energy Technology Data Exchange (ETDEWEB)

    Quattromani, F.; Lampe, R. (eds.) [Texas Tech Univ. Health Sciences Center, School of Medicine, Lubbock, TX (United States); Handal, G.A. [Texas Tech Univ. Health Sciences Center, School of Medicine, El Paso, TX (United States)

    2008-07-01

    The book contains the following contributions: Airway, head, neck; allergy, immunology rheumatology; pediatric cardiac imaging; child abuse; chromosomal abnormalities; conscious sedation; contrast agents and radiation protection; pediatric gastrointestinal imaging; genetic disorders in infants and children; pediatric genitourinary imaging; pediatric hematology, oncology imaging; pediatric intenrventional radiology; metabolic and vitamin disorders; muscoskeletal disorders (osteoradiology); neonatology imaging; pediatric neuroimaging; imaging of the respiratory tract in infants and children; vascular anomalies.

  2. Improvement of Sidestream Dark Field Imaging with an Image Acquisition Stabilizer

    NARCIS (Netherlands)

    G. Balestra (Gianmarco); R. Bezemer (Rick); E.C. Boerma (Christiaan); Z-Y. Yong (Ze-Yie); K.D. Sjauw (Krishan); A.E. Engstrom (Annemarie); M. Koopmans (Matty); C. Ince (Can)

    2010-01-01

    textabstractBackground: In the present study we developed, evaluated in volunteers, and clinically validated an image acquisition stabilizer (IAS) for Sidestream Dark Field (SDF) imaging.Methods: The IAS is a stainless steel sterilizable ring which fits around the SDF probe tip. The IAS creates

  3. Improvement of Sidestream Dark Field Imaging with an Image Acquisition Stabilizer

    NARCIS (Netherlands)

    Balestra, Gianmarco M.; Bezemer, Rick; Boerma, E. Christiaan; Yong, Ze-Yie; Sjauw, Krishan D.; Engstrom, Annemarie E.; Koopmans, Matty; Ince, Can

    2010-01-01

    ABSTRACT: BACKGROUND: In the present study we developed, evaluated in volunteers, and clinically validated an image acquisition stabilizer (IAS) for Sidestream Dark Field (SDF) imaging. METHODS: The IAS is a stainless steel sterilizable ring which fits around the SDF probe tip. The IAS creates

  4. Real-Time Data Acquisition for Single Photon Imaging Detector

    Science.gov (United States)

    Hu, Kun; Wang, Xu; Yao, Yuan; Gao, Xin; Jin, Ge

    2016-04-01

    We will describe a real-time data acquisition (DAQ) system for an MCP-based photon imaging detector, which is read out with the induced charge scheme by a wedge-and-strip anode (WSA) employing position-dependent charge partitioning. The traditional filter and shaping technique is employed in the position decoding electronics. Data processing and algorithms are completely implemented via field programmable gate array (FPGA). To achieve the high-precision charge measurement and high count rate, the whole module requires good dynamic range and short dead time. The latest results show the RMS resolution of the micro channel plate (MCP) detector with an effective diameter of 30 mm can reach 60 μm in the horizontal and vertical directions, respectively. Due to the real-time imaging, the module can support count rates up to 500 kHz. However, the pulse pile-up limits the ultimate count rate.

  5. Motion-gated acquisition for in vivo optical imaging

    Science.gov (United States)

    Gioux, Sylvain; Ashitate, Yoshitomo; Hutteman, Merlijn; Frangioni, John V.

    2009-11-01

    Wide-field continuous wave fluorescence imaging, fluorescence lifetime imaging, frequency domain photon migration, and spatially modulated imaging have the potential to provide quantitative measurements in vivo. However, most of these techniques have not yet been successfully translated to the clinic due to challenging environmental constraints. In many circumstances, cardiac and respiratory motion greatly impair image quality and/or quantitative processing. To address this fundamental problem, we have developed a low-cost, field-programmable gate array-based, hardware-only gating device that delivers a phase-locked acquisition window of arbitrary delay and width that is derived from an unlimited number of pseudo-periodic and nonperiodic input signals. All device features can be controlled manually or via USB serial commands. The working range of the device spans the extremes of mouse electrocardiogram (1000 beats per minute) to human respiration (4 breaths per minute), with timing resolution pig heart. This gating device should help to enable the clinical translation of promising new optical imaging technologies.

  6. Rapid imaging of free radicals in vivo using field cycled PEDRI.

    Science.gov (United States)

    Puwanich, P; Lurie, D J; Foster, M A

    1999-12-01

    Imaging of free radicals in vivo using an interleaved field-cycled proton-electron double-resonance imaging (FC-PEDRI) pulse sequence has recently been investigated. In this work, in order to reduce the EPR (electron paramagnetic resonance) irradiation power required and the imaging time, a centric reordered snapshot FC-PEDRI pulse sequence has been implemented. This is based on the FLASH pulse sequence with a very short repetition time and the use of centric reordering of the phase-encoding gradient, allowing the most significant free induction decay (FID) signals to be collected before the signal enhancement decays significantly. A new technique of signal phaseshift correction was required to eliminate ghost artefacts caused by the instability of the main magnetic field after field cycling. An FID amplitude correction scheme has also been implemented to reduce edge enhancement artefacts caused by the rapid change of magnetization population before reaching the steady state. Using the rapid pulse sequence, the time required for acquisition of a 64 x 64 pixel FC-PEDRI image was reduced to 6 s per image compared with about 2.5 min with the conventional pulse sequence. The EPR irradiation power applied to the sample was reduced by a factor of approximately 64. Although the resulting images obtained by the rapid pulse sequence have a lower signal to noise than those obtained by a normal interleaved FC-PEDRI pulse sequence, the results show that rapid imaging of free radicals in vivo using snapshot FC-PEDRI is possible.

  7. Influence of the arm position in myocardial perfusion imaging acquisition

    Directory of Open Access Journals (Sweden)

    Marisa Izaki

    2014-07-01

    Full Text Available Objective: despite the technologic advances in myocardial perfusion imaging, we keep using an uncomfortable and sometimes impracticable patient position - supine with arms raised above the head (U. The purpose of this study was to investigate whether perfusion and functional cardiac gated SPECT scan results of acquisition U are equivalent to another position modality: supine with arms down at the sides of the trunk (D. Methods and Results: we performed U acquisition and in sequence D acquisition in 120 patients (pts using a one-day MPI (rest-gated/stress, with 99mTc-sestamibi (370 MBq and 1110 MBq. Images were processed by the iterative reconstruction method (OSEM. Rest (R and stress (S studies were scored using 17-segments model. Functional parameters (left ventricular ejection fraction, and volumes were automatically obtained by the quantitative gated SPECT (QGS program. According to the degree of stress defects observed in U study, the patients were categorized in two subgroups: normal (SSS ≤ 3 or 3 or ≥ 5%. Shoulder/back pain occurred in 23.3% of U patients and in 5% of D. No significant differences between U and D were found for SSS (p = 0.82 and SRS (p = 0.74 in normal group. In abnormal group, good correlation was found between U and D modes for SSS (Rho = 0.95, p = 0.0001 and SRS (Rho = 0.96 p = 0.0001, but the mean SSS (12.53 ± 7.54 and SRS (10.60 ± 7.08 values of D were significantly lower (p < 0.05 than SSS (13.43 ± 6.81 and SRS (11.33 ± 6.97 of U mode. Function measurements presented good correlations, except for end-diastolic volume (p = 0.0001. Conclusion: although D mode appears to be more comfortable and presented a good correlation with U values of SSS and SRS, in abnormal pts, the extent and severity of defects can be underestimated. Considering clinical implications of an accurate perfusion measurement, the acquisition with the arms down should be avoided.

  8. Silhouette-based approach of 3D image reconstruction for automated image acquisition using robotic arm

    Science.gov (United States)

    Azhar, N.; Saad, W. H. M.; Manap, N. A.; Saad, N. M.; Syafeeza, A. R.

    2017-06-01

    This study presents the approach of 3D image reconstruction using an autonomous robotic arm for the image acquisition process. A low cost of the automated imaging platform is created using a pair of G15 servo motor connected in series to an Arduino UNO as a main microcontroller. Two sets of sequential images were obtained using different projection angle of the camera. The silhouette-based approach is used in this study for 3D reconstruction from the sequential images captured from several different angles of the object. Other than that, an analysis based on the effect of different number of sequential images on the accuracy of 3D model reconstruction was also carried out with a fixed projection angle of the camera. The effecting elements in the 3D reconstruction are discussed and the overall result of the analysis is concluded according to the prototype of imaging platform.

  9. Computationally rapid method of estimating signal-to-noise ratio for phased array image reconstructions.

    Science.gov (United States)

    Wiens, Curtis N; Kisch, Shawn J; Willig-Onwuachi, Jacob D; McKenzie, Charles A

    2011-10-01

    Measuring signal-to-noise ratio (SNR) for parallel MRI reconstructions is difficult due to spatially dependent noise amplification. Existing approaches for measuring parallel MRI SNR are limited because they are not applicable to all reconstructions, require significant computation time, or rely on repeated image acquisitions. A new SNR estimation approach is proposed, a hybrid of the repeated image acquisitions method detailed in the National Electrical Manufacturers Association (NEMA) standard and the Monte Carlo based pseudo-multiple replica method, in which the difference between images reconstructed from the unaltered acquired data and that same data reconstructed after the addition of calibrated pseudo-noise is used to estimate the noise in the parallel MRI image reconstruction. This new noise estimation method can be used to rapidly compute the pixel-wise SNR of the image generated from any parallel MRI reconstruction of a single acquisition. SNR maps calculated with the new method are validated against existing SNR calculation techniques. Copyright © 2011 Wiley-Liss, Inc.

  10. Image Acquisition of Robust Vision Systems to Monitor Blurred Objects in Hazy Smoking Environments

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Yongjin; Park, Seungkyu; Baik, Sunghoon; Kim, Donglyul; Nam, Sungmo; Jeong, Kyungmin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    Image information in disaster area or radiation area of nuclear industry is an important data for safety inspection and preparing appropriate damage control plans. So, robust vision system for structures and facilities in blurred smoking environments, such as the places of a fire and detonation, is essential in remote monitoring. Vision systems can't acquire an image when the illumination light is blocked by disturbance materials, such as smoke, fog, dust. The vision system based on wavefront correction can be applied to blurred imaging environments and the range-gated imaging system can be applied to both of blurred imaging and darken light environments. Wavefront control is a widely used technique to improve the performance of optical systems by actively correcting wavefront distortions, such as atmospheric turbulence, thermally-induced distortions, and laser or laser device aberrations, which can reduce the peak intensity and smear an acquired image. The principal applications of wavefront control are for improving the image quality in optical imaging systems such as infrared astronomical telescopes, in imaging and tracking rapidly moving space objects, and in compensating for laser beam distortion through the atmosphere. A conventional wavefront correction system consists of a wavefront sensor, a deformable mirror and a control computer. The control computer measures the wavefront distortions using a wavefront sensor and corrects it using a deformable mirror in a closed-loop. Range-gated imaging (RGI) is a direct active visualization technique using a highly sensitive image sensor and a high intensity illuminant. Currently, the range-gated imaging technique providing 2D and 3D images is one of emerging active vision technologies. The range-gated imaging system gets vision information by summing time sliced vision images. In the RGI system, a high intensity illuminant illuminates for ultra-short time and a highly sensitive image sensor is gated by ultra

  11. Acquisition of STEM Images by Adaptive Compressive Sensing

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Weiyi; Feng, Qianli; Srinivasan, Ramprakash; Stevens, Andrew; Browning, Nigel D.

    2017-07-01

    Compressive Sensing (CS) allows a signal to be sparsely measured first and accurately recovered later in software [1]. In scanning transmission electron microscopy (STEM), it is possible to compress an image spatially by reducing the number of measured pixels, which decreases electron dose and increases sensing speed [2,3,4]. The two requirements for CS to work are: (1) sparsity of basis coefficients and (2) incoherence of the sensing system and the representation system. However, when pixels are missing from the image, it is difficult to have an incoherent sensing matrix. Nevertheless, dictionary learning techniques such as Beta-Process Factor Analysis (BPFA) [5] are able to simultaneously discover a basis and the sparse coefficients in the case of missing pixels. On top of CS, we would like to apply active learning [6,7] to further reduce the proportion of pixels being measured, while maintaining image reconstruction quality. Suppose we initially sample 10% of random pixels. We wish to select the next 1% of pixels that are most useful in recovering the image. Now, we have 11% of pixels, and we want to decide the next 1% of “most informative” pixels. Active learning methods are online and sequential in nature. Our goal is to adaptively discover the best sensing mask during acquisition using feedback about the structures in the image. In the end, we hope to recover a high quality reconstruction with a dose reduction relative to the non-adaptive (random) sensing scheme. In doing this, we try three metrics applied to the partial reconstructions for selecting the new set of pixels: (1) variance, (2) Kullback-Leibler (KL) divergence using a Radial Basis Function (RBF) kernel, and (3) entropy. Figs. 1 and 2 display the comparison of Peak Signal-to-Noise (PSNR) using these three different active learning methods at different percentages of sampled pixels. At 20% level, all the three active learning methods underperform the original CS without active learning. However

  12. Rapid imaging of free radicals in vivo using hybrid FISP field-cycled PEDRI

    Science.gov (United States)

    Youngdee, Wiwat; Lurie, David J.; Foster, Margaret A.

    2002-04-01

    A new pulse sequence for rapid imaging of free radicals is presented which combines snapshot imaging methods and conventional field-cycled proton electron double resonance imaging (FC-PEDRI). The new sequence allows the number of EPR irradiation periods to be optimized to obtain an acceptable SNR and spatial resolution of free radical distribution in the final image while reducing the RF power deposition and increasing the temporal resolution. Centric reordered phase encoding has been employed to counter the problem of rapid decay of the Overhauser-enhanced signal. A phase-correction scheme has also been used to correct problems arising from instability of the magnetic field following field-cycling. In vivo experiments were carried out using triaryl methyl free radical contrast agent, injected at a dose of 0.214 mmol kg-1 body weight in anaesthetized adult male Sprague-Dawley rats. Transaxial images through the abdomen were collected using 1, 2, 4 and 8 EPR irradiation periods. Using 4 EPR irradiation periods it was possible to generate free radical distributions of acceptable SNR and resolution. The EPR power deposition is reduced by a factor of 16 and the acquisition time is reduced by a factor of 4 compared to an acquisition using the conventional FC-PEDRI pulse sequence.

  13. NOTE: A method for controlling image acquisition in electronic portal imaging devices

    Science.gov (United States)

    Glendinning, A. G.; Hunt, S. G.; Bonnett, D. E.

    2001-02-01

    Certain types of camera-based electronic portal imaging devices (EPIDs) which initiate image acquisition based on sensing a change in video level have been observed to trigger unreliably at the beginning of dynamic multileaf collimation sequences. A simple, novel means of controlling image acquisition with an Elekta linear accelerator (Elekta Oncology Systems, Crawley, UK) is proposed which is based on illumination of a photodetector (ORP-12, Silonex Inc., Plattsburgh, NY, USA) by the electron gun of the accelerator. By incorporating a simple trigger circuit it is possible to derive a beam on/off status signal which changes at least 100 ms before any dose is measured by the accelerator. The status signal does not return to the beam-off state until all dose has been delivered and is suitable for accelerator pulse repetition frequencies of 50-400 Hz. The status signal is thus a reliable means of indicating the initiation and termination of radiation exposure, and thus controlling image acquisition of such EPIDs for this application.

  14. Biometric iris image acquisition system with wavefront coding technology

    Science.gov (United States)

    Hsieh, Sheng-Hsun; Yang, Hsi-Wen; Huang, Shao-Hung; Li, Yung-Hui; Tien, Chung-Hao

    2013-09-01

    Biometric signatures for identity recognition have been practiced for centuries. Basically, the personal attributes used for a biometric identification system can be classified into two areas: one is based on physiological attributes, such as DNA, facial features, retinal vasculature, fingerprint, hand geometry, iris texture and so on; the other scenario is dependent on the individual behavioral attributes, such as signature, keystroke, voice and gait style. Among these features, iris recognition is one of the most attractive approaches due to its nature of randomness, texture stability over a life time, high entropy density and non-invasive acquisition. While the performance of iris recognition on high quality image is well investigated, not too many studies addressed that how iris recognition performs subject to non-ideal image data, especially when the data is acquired in challenging conditions, such as long working distance, dynamical movement of subjects, uncontrolled illumination conditions and so on. There are three main contributions in this paper. Firstly, the optical system parameters, such as magnification and field of view, was optimally designed through the first-order optics. Secondly, the irradiance constraints was derived by optical conservation theorem. Through the relationship between the subject and the detector, we could estimate the limitation of working distance when the camera lens and CCD sensor were known. The working distance is set to 3m in our system with pupil diameter 86mm and CCD irradiance 0.3mW/cm2. Finally, We employed a hybrid scheme combining eye tracking with pan and tilt system, wavefront coding technology, filter optimization and post signal recognition to implement a robust iris recognition system in dynamic operation. The blurred image was restored to ensure recognition accuracy over 3m working distance with 400mm focal length and aperture F/6.3 optics. The simulation result as well as experiment validates the proposed code

  15. Rapid Indoor Data Acquisition for Ladm-Based 3d Cadastre Model

    Science.gov (United States)

    Jamali, A.; Boguslawski, P.; Duncan, E. E.; Gold, C. M.; Rahman, A. Abdul

    2013-09-01

    2D cadastre has been in existence for decades and most countries have found it convenient. However, in complex situations it has been found to be inadequate as ownership becomes difficult to realise. 3D cadastre data was previously not being collected, thus, making such data even more difficult to realise. 3D data collection for 3D cadastre is one of the main issues for practising surveyors. Several ways of obtaining 3D data exist namely, traditional surveying, terrestrial laser scanning and from Computer Aided Design (CAD) sources. Various data sources have different data structure and a generalized data structure for 3D cadastre hardly reported. A simple and rapid method for indoor data acquisition is proposed. This seeks to determine if the dual half edge data structure is suitable for 3D cadastre. The dual half edge data structure is applied within a graphical user interface. The concept for indoor surveying or data acquisition within the LA_SpatialUnit of the Land Administration Domain Model (LADM) is presented and proposed.

  16. Improvement of sidestream dark field imaging with an image acquisition stabilizer.

    Science.gov (United States)

    Balestra, Gianmarco M; Bezemer, Rick; Boerma, E Christiaan; Yong, Ze-Yie; Sjauw, Krishan D; Engstrom, Annemarie E; Koopmans, Matty; Ince, Can

    2010-07-13

    In the present study we developed, evaluated in volunteers, and clinically validated an image acquisition stabilizer (IAS) for Sidestream Dark Field (SDF) imaging. The IAS is a stainless steel sterilizable ring which fits around the SDF probe tip. The IAS creates adhesion to the imaged tissue by application of negative pressure. The effects of the IAS on the sublingual microcirculatory flow velocities, the force required to induce pressure artifacts (PA), the time to acquire a stable image, and the duration of stable imaging were assessed in healthy volunteers. To demonstrate the clinical applicability of the SDF setup in combination with the IAS, simultaneous bilateral sublingual imaging of the microcirculation were performed during a lung recruitment maneuver (LRM) in mechanically ventilated critically ill patients. One SDF device was operated handheld; the second was fitted with the IAS and held in position by a mechanic arm. Lateral drift, number of losses of image stability and duration of stable imaging of the two methods were compared. Five healthy volunteers were studied. The IAS did not affect microcirculatory flow velocities. A significantly greater force had to applied onto the tissue to induced PA with compared to without IAS (0.25 +/- 0.15 N without vs. 0.62 +/- 0.05 N with the IAS, p lateral SDF image stability and thereby increased the critical force required to induce pressure artifacts. The IAS ensured a significantly increased duration of maintaining a stable image sequence.

  17. Rapid HIFU autofocusing using the entire MR-ARFI image

    Energy Technology Data Exchange (ETDEWEB)

    Grissom, William A.; Kaye, Elena; Pauly, Kim Butts; Zur, Yuval; Yeo, Desmond; Medan, Yoav; Davis, Cynthia [Biomedical Engineering, Vanderbilt University, Nashville, Tennessee (United States); Electrical Engineering, Stanford University, Stanford, California (United States); Radiology, Stanford University, Stanford, California (United States); GE Healthcare, Haifa (Israel); GE Global Research, Niskayuna, New York (United States); Biomedical Engineering, Technion IIT, Haifa (Israel); GE Global Research, Niskayuna, New York (United States)

    2012-11-28

    Phase aberrations and attenuations caused by bone can defocus HIFU in the brain and organs behind the ribcage. To refocus the beam, MR-ARFI can be used to measure tissue displacements created by each element in the transducer, and optimize driving signal delays and amplitudes. We introduce a new MR-ARFI-based autofocusing method that requires many fewer image acquisitions than current methods. The method is validated in simulations of bone and brain HIFU transducers, and compared to a conventional method.

  18. An asynchronous, pipelined, electronic acquisition system for Active Matrix Flat-Panel Imagers (AMFPIs)

    CERN Document Server

    Huang, W; Berry, J; Maolinbay, M; Martelli, C; Mody, P; Nassif, S; Yeakey, M

    1999-01-01

    The development of a full-custom electronic acquisition system designed for readout of large-area active matrix flat-panel imaging arrays is reported. The arrays, which comprise two-dimensional matrices of pixels utilizing amorphous silicon thin-film transistors, are themselves under development for a wide variety of X-ray imaging applications. The acquisition system was specifically designed to facilitate detailed, quantitative investigations of the properties of these novel imaging arrays and contains significant enhancements compared to a previously developed acquisition system. These enhancements include pipelined preamplifier circuits to allow faster readout speed, expanded addressing capabilities allowing a maximum of 4096 array data lines, and on-board summing of image frames. The values of many acquisition system parameters, including timings and voltages, may be specified and downloaded from a host computer. Once acquisition is enabled, the system operates asynchronously of its host computer. The sys...

  19. Range-Image Acquisition for Discriminated Objects in a Range-gated Robot Vision System

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seung-Kyu; Ahn, Yong-Jin; Park, Nak-Kyu; Baik, Sung-Hoon; Choi, Young-Soo; Jeong, Kyung-Min [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    The imaging capability of a surveillance vision system from harsh low-visibility environments such as in fire and detonation areas is a key function to monitor the safety of the facilities. 2D and range image data acquired from low-visibility environment are important data to assess the safety and prepare appropriate countermeasures. Passive vision systems, such as conventional camera and binocular stereo vision systems usually cannot acquire image information when the reflected light is highly scattered and absorbed by airborne particles such as fog. In addition, the image resolution captured through low-density airborne particles is decreased because the image is blurred and dimmed by the scattering, emission and absorption. Active vision systems, such as structured light vision and projected stereo vision are usually more robust for harsh environment than passive vision systems. However, the performance is considerably decreased in proportion to the density of the particles. The RGI system provides 2D and range image data from several RGI images and it moreover provides clear images from low-visibility fog and smoke environment by using the sum of time-sliced images. Nowadays, the Range-gated (RG) imaging is an emerging technology in the field of surveillance for security applications, especially in the visualization of invisible night and fog environment. Although RGI viewing was discovered in the 1960's, this technology is, nowadays becoming more applicable by virtue of the rapid development of optical and sensor technologies. Especially, this system can be adopted in robot-vision system by virtue of its compact portable configuration. In contrast to passive vision systems, this technology enables operation even in harsh environments like fog and smoke. During the past decades, several applications of this technology have been applied in target recognition and in harsh environments, such as fog, underwater vision. Also, this technology has been

  20. Multiple half-second acquisition method of the moving knee joint. Kinematic MR imaging of the anterior cruciate ligament

    Energy Technology Data Exchange (ETDEWEB)

    Niitsu, Mamoru; Ikeda, Kotaroh; Fukubayashi, Tohru; Echigo, Junko; Itai, Yuji [Tsukuba Univ., Ibaraki (Japan). Inst. of Clinical Medicine

    1996-10-01

    The objective of this study was to delineate the moving anterior cruciate ligament (ACL) with multiple rapid magnetic resonance (MR) imaging. Rapid gradient echo MR images with an one-shot acquisition time of a half-second were accomplished by short repetition time and phase encoding reduction. Using a mobile knee brace and a flexible surface coil, half-second acquisitions were sequentially acquired during active, constant knee movement. Sixteen knees with intact ACLs and 27 knees with arthroscopically proven ACL tears were examined. Normal ACLs were identified as moving linear low-intensities. The ligaments were readily identified as straight or minimally curved structures when the knee was in semi-flexion compared to the knee extension. Torn ACLs were demonstrated as moving fragments or an amorphous configuration. Intermittent appearances of joint fluid interrupted the ligamentous continuities. Compared to the static images, no significant superiority of the kinematic imaging was found in diagnosis of ACL tears. However, this instant kinematic imaging is feasible with a standard MR system and can provide morphological information for functional analysis of the knee. (author)

  1. Improvement of Sidestream Dark Field Imaging with an Image Acquisition Stabilizer

    Directory of Open Access Journals (Sweden)

    Sjauw Krishan D

    2010-07-01

    Full Text Available Abstract Background In the present study we developed, evaluated in volunteers, and clinically validated an image acquisition stabilizer (IAS for Sidestream Dark Field (SDF imaging. Methods The IAS is a stainless steel sterilizable ring which fits around the SDF probe tip. The IAS creates adhesion to the imaged tissue by application of negative pressure. The effects of the IAS on the sublingual microcirculatory flow velocities, the force required to induce pressure artifacts (PA, the time to acquire a stable image, and the duration of stable imaging were assessed in healthy volunteers. To demonstrate the clinical applicability of the SDF setup in combination with the IAS, simultaneous bilateral sublingual imaging of the microcirculation were performed during a lung recruitment maneuver (LRM in mechanically ventilated critically ill patients. One SDF device was operated handheld; the second was fitted with the IAS and held in position by a mechanic arm. Lateral drift, number of losses of image stability and duration of stable imaging of the two methods were compared. Results Five healthy volunteers were studied. The IAS did not affect microcirculatory flow velocities. A significantly greater force had to applied onto the tissue to induced PA with compared to without IAS (0.25 ± 0.15 N without vs. 0.62 ± 0.05 N with the IAS, p Conclusions The present study has validated the use of an IAS for improvement of SDF imaging by demonstrating that the IAS did not affect microcirculatory perfusion in the microscopic field of view. The IAS improved both axial and lateral SDF image stability and thereby increased the critical force required to induce pressure artifacts. The IAS ensured a significantly increased duration of maintaining a stable image sequence.

  2. Noun Imageability Facilitates the Acquisition of Plurals: Survival Analysis of Plural Emergence in Children

    Czech Academy of Sciences Publication Activity Database

    Smolík, Filip

    2014-01-01

    Roč. 43, č. 4 (2014), s. 335-350 ISSN 0090-6905 R&D Projects: GA ČR GAP407/10/2047 Institutional support: RVO:68081740 Keywords : Language acquisition * Imageability * Morphology * Acquisition of inflections * Semantic generality Subject RIV: AN - Psychology Impact factor: 0.633, year: 2014

  3. Imaging inflammation in mouse colon using a rapid stage-scanning confocal fluorescence microscope.

    Science.gov (United States)

    Saldua, Meagan A; Olsovsky, Cory A; Callaway, Evelyn S; Chapkin, Robert S; Maitland, Kristen C

    2012-01-01

    Large area confocal microscopy may provide fast, high-resolution image acquisition for evaluation of tissue in pre-clinical studies with reduced tissue processing in comparison to histology. We present a rapid beam and stage-scanning confocal fluorescence microscope to image cellular and tissue features along the length of the entire excised mouse colon. The beam is scanned at 8,333 lines/sec by a polygon scanning mirror while the specimen is scanned in the orthogonal axis by a motorized translation stage with a maximum speed of 7 mm/sec. A single 1 × 60 mm(2) field of view image spanning the length of the mouse colon is acquired in 10 s. Z-projection images generated from axial image stacks allow high resolution imaging of the surface of non-flat specimens. In contrast to the uniform size, shape, and distribution of colon crypts in confocal images of normal colon, confocal images of chronic bowel inflammation exhibit heterogeneous tissue structure with localized severe crypt distortion.

  4. A high-resolution optical measurement system for rapid acquisition of radiation flux density maps

    Science.gov (United States)

    Thelen, Martin; Raeder, Christian; Willsch, Christian; Dibowski, Gerd

    2017-06-01

    To identify the power and flux density of concentrated solar radiation the Institute of Solar Research at the German Aerospace Center (DLR - Deutsches Zentrum für Luft-und Raumfahrt e. V.) has used the camera-based measurement system FATMES (Flux and Temperature Measurement System) since 1995. The disadvantages of low resolution, difficult handling and poor computing power required a revision of the existing measurement system. The measurement system FMAS (Flux Mapping Acquisition system) is equipped with state-of-the-art-hardware, is compatible with computers off-the-shelf and is programmed in LabView. The expenditure of time for an image evaluation is reduced by the factor 60 compared to FATMES. The new measurement system is no longer associated with the facilities Solar Furnace and High Flux Solar Simulator at the DLR in Cologne but is also applicable as a mobile system. The data and the algorithms are transparent throughout the complete process. The measurement accuracy of FMAS is determined to at most ±3 % until now. The error of measurement of FATMES is at least 2 % higher according to the conducted comparison tests.

  5. A rapid and robust gradient measurement technique using dynamic single-point imaging.

    Science.gov (United States)

    Jang, Hyungseok; McMillan, Alan B

    2017-09-01

    We propose a new gradient measurement technique based on dynamic single-point imaging (SPI), which allows simple, rapid, and robust measurement of k-space trajectory. To enable gradient measurement, we utilize the variable field-of-view (FOV) property of dynamic SPI, which is dependent on gradient shape. First, one-dimensional (1D) dynamic SPI data are acquired from a targeted gradient axis, and then relative FOV scaling factors between 1D images or k-spaces at varying encoding times are found. These relative scaling factors are the relative k-space position that can be used for image reconstruction. The gradient measurement technique also can be used to estimate the gradient impulse response function for reproducible gradient estimation as a linear time invariant system. The proposed measurement technique was used to improve reconstructed image quality in 3D ultrashort echo, 2D spiral, and multi-echo bipolar gradient-echo imaging. In multi-echo bipolar gradient-echo imaging, measurement of the k-space trajectory allowed the use of a ramp-sampled trajectory for improved acquisition speed (approximately 30%) and more accurate quantitative fat and water separation in a phantom. The proposed dynamic SPI-based method allows fast k-space trajectory measurement with a simple implementation and no additional hardware for improved image quality. Magn Reson Med 78:950-962, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  6. Improving Rapid Acquisition: A Review of the Riverine Command Boat Procurement

    Science.gov (United States)

    2013-12-01

    Management System AAC acquisition advice code ACAT acquisition category ALT administrative lead-time AMD average monthly demand APL...formal system for acquisition and follows guidelines set forth in the DoD 5000 series first released in 1971. It is a milestone-driven, low-risk...procured, materials. The Navy first issued maintenance guidelines in January 2011. The class-maintenance plan for the RCB was published in February 2013

  7. Rapid acquisition strategy for functional T1ρ mapping of the brain.

    Science.gov (United States)

    Johnson, Casey P; Heo, Hye-Young; Thedens, Daniel R; Wemmie, John A; Magnotta, Vincent A

    2014-11-01

    Functional T1ρ mapping has been proposed as a method to assess pH and metabolism dynamics in the brain with high spatial and temporal resolution. The purpose of this work is to describe and evaluate a variant of the spin-locked echo-planar imaging sequence for functional T1ρ mapping at 3T. The proposed sequence rapidly acquires a time series of T1ρ maps with 4.0second temporal resolution and 10 slices of volumetric coverage. Simulation, phantom, and in vivo experiments are used to evaluate many aspects of the sequence and its implementation including fidelity of measured T1ρ dynamics, potential confounds to the T1ρ response, imaging parameter tradeoffs, time series analysis approaches, and differences compared to blood oxygen level dependent functional magnetic resonance imaging. It is shown that the high temporal resolution and volumetric coverage of the sequence are obtained with some expense including underestimation of the T1ρ response, sensitivity to T1 dynamics, and reduced signal-to-noise ratio. In vivo studies using a flashing checkerboard functional magnetic resonance imaging paradigm suggest differences between T1ρ and blood oxygen level dependent activation patterns. Possible sources of the functional T1ρ response and potential sequence improvements are discussed. The capability of T1ρ to map whole-brain pH and metabolism dynamics with high temporal and spatial resolution is potentially unique and warrants further investigation and development. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Model-based estimation of breast percent density in raw and processed full-field digital mammography images from image-acquisition physics and patient-image characteristics

    Science.gov (United States)

    Keller, Brad M.; Nathan, Diane L.; Conant, Emily F.; Kontos, Despina

    2012-03-01

    Breast percent density (PD%), as measured mammographically, is one of the strongest known risk factors for breast cancer. While the majority of studies to date have focused on PD% assessment from digitized film mammograms, digital mammography (DM) is becoming increasingly common, and allows for direct PD% assessment at the time of imaging. This work investigates the accuracy of a generalized linear model-based (GLM) estimation of PD% from raw and postprocessed digital mammograms, utilizing image acquisition physics, patient characteristics and gray-level intensity features of the specific image. The model is trained in a leave-one-woman-out fashion on a series of 81 cases for which bilateral, mediolateral-oblique DM images were available in both raw and post-processed format. Baseline continuous and categorical density estimates were provided by a trained breast-imaging radiologist. Regression analysis is performed and Pearson's correlation, r, and Cohen's kappa, κ, are computed. The GLM PD% estimation model performed well on both processed (r=0.89, pimages. Model agreement with radiologist assigned density categories was also high for processed (κ=0.79, pimages. Model-based prediction of breast PD% could allow for a reproducible estimation of breast density, providing a rapid risk assessment tool for clinical practice.

  9. On-site Rapid Diagnosis of Intracranial Hematoma using Portable Multi-slice Microwave Imaging System

    Science.gov (United States)

    Mobashsher, Ahmed Toaha; Abbosh, A. M.

    2016-11-01

    Rapid, on-the-spot diagnostic and monitoring systems are vital for the survival of patients with intracranial hematoma, as their conditions drastically deteriorate with time. To address the limited accessibility, high costs and static structure of currently used MRI and CT scanners, a portable non-invasive multi-slice microwave imaging system is presented for accurate 3D localization of hematoma inside human head. This diagnostic system provides fast data acquisition and imaging compared to the existing systems by means of a compact array of low-profile, unidirectional antennas with wideband operation. The 3D printed low-cost and portable system can be installed in an ambulance for rapid on-site diagnosis by paramedics. In this paper, the multi-slice head imaging system’s operating principle is numerically analysed and experimentally validated on realistic head phantoms. Quantitative analyses demonstrate that the multi-slice head imaging system is able to generate better quality reconstructed images providing 70% higher average signal to clutter ratio, 25% enhanced maximum signal to clutter ratio and with around 60% hematoma target localization compared to the previous head imaging systems. Nevertheless, numerical and experimental results demonstrate that previous reported 2D imaging systems are vulnerable to localization error, which is overcome in the presented multi-slice 3D imaging system. The non-ionizing system, which uses safe levels of very low microwave power, is also tested on human subjects. Results of realistic phantom and subjects demonstrate the feasibility of the system in future preclinical trials.

  10. Investigating the Feasibility of Rapid MRI for Image-Guided Motion Management in Lung Cancer Radiotherapy

    Directory of Open Access Journals (Sweden)

    Amit Sawant

    2014-01-01

    Full Text Available Cycle-to-cycle variations in respiratory motion can cause significant geometric and dosimetric errors in the administration of lung cancer radiation therapy. A common limitation of the current strategies for motion management is that they assume a constant, reproducible respiratory cycle. In this work, we investigate the feasibility of using rapid MRI for providing long-term imaging of the thorax in order to better capture cycle-to-cycle variations. Two nonsmall-cell lung cancer patients were imaged (free-breathing, no extrinsic contrast, and 1.5 T scanner. A balanced steady-state-free-precession (b-SSFP sequence was used to acquire cine-2D and cine-3D (4D images. In the case of Patient 1 (right midlobe lesion, ~40 mm diameter, tumor motion was well correlated with diaphragmatic motion. In the case of Patient 2, (left upper-lobe lesion, ~60 mm diameter, tumor motion was poorly correlated with diaphragmatic motion. Furthermore, the motion of the tumor centroid was poorly correlated with the motion of individual points on the tumor boundary, indicating significant rotation and/or deformation. These studies indicate that image quality and acquisition speed of cine-2D MRI were adequate for motion monitoring. However, significant improvements are required to achieve comparable speeds for truly 4D MRI. Despite several challenges, rapid MRI offers a feasible and attractive tool for noninvasive, long-term motion monitoring.

  11. Imageability predicts the age of acquisition of verbs in Chinese children*

    OpenAIRE

    Ma, Weiyi; Golinkoff, Roberta Michnick; Hirsh-Pasek, Kathy; McDonough, Colleen; Tardif, Twila

    2008-01-01

    Verbs are harder to learn than nouns in English and in many other languages, but are relatively easy to learn in Chinese. This paper evaluates one potential explanation for these findings by examining the construct of imageability, or the ability of a word to produce a mental image. Chinese adults rated the imageability of Chinese words from the Chinese Communicative Development Inventory (Tardif et al., in press). Imageability ratings were a reliable predictor of age of acquisition in Chines...

  12. An evaluation on CT image acquisition method for medical VR applications

    Science.gov (United States)

    Jang, Seong-wook; Ko, Junho; Yoo, Yon-sik; Kim, Yoonsang

    2017-02-01

    Recent medical virtual reality (VR) applications to minimize re-operations are being studied for improvements in surgical efficiency and reduction of operation error. The CT image acquisition method considering three-dimensional (3D) modeling for medical VR applications is important, because the realistic model is required for the actual human organ. However, the research for medical VR applications has focused on 3D modeling techniques and utilized 3D models. In addition, research on a CT image acquisition method considering 3D modeling has never been reported. The conventional CT image acquisition method involves scanning a limited area of the lesion for the diagnosis of doctors once or twice. However, the medical VR application is required to acquire the CT image considering patients' various postures and a wider area than the lesion. A wider area than the lesion is required because of the necessary process of comparing bilateral sides for dyskinesia diagnosis of the shoulder, pelvis, and leg. Moreover, patients' various postures are required due to the different effects on the musculoskeletal system. Therefore, in this paper, we perform a comparative experiment on the acquired CT images considering image area (unilateral/bilateral) and patients' postures (neutral/abducted). CT images are acquired from 10 patients for the experiments, and the acquired CT images are evaluated based on the length per pixel and the morphological deviation. Finally, by comparing the experiment results, we evaluate the CT image acquisition method for medical VR applications.

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

    Directory of Open Access Journals (Sweden)

    Wei Long

    2016-09-01

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

  14. Threading libraries performance when applied to image acquisition and processing in a forensic application

    OpenAIRE

    Bermúdez, Carlos

    2013-01-01

    Peer-reviewed Based on concerns during ballistics identification, a new system for ballistics image acquisition and data processing is proposed. Since image processing consists of high CPU load rates, a comparison of three different threading libraries is presented, concluding that parallel processing enhances ballistics identification speed.

  15. Precise acquisition and unsupervised segmentation of multi-spectral images

    DEFF Research Database (Denmark)

    Gomez, David Delgado; Clemmensen, Line Katrine Harder; Ersbøll, Bjarne Kjær

    2007-01-01

    In this work, an integrated imaging system to obtain accurate and reproducible multi-spectral images and a novel multi-spectral image segmentation algorithm are proposed. The system collects up to 20 different spectral bands within a range that vary from 395 nm to 970 nm. The system is designed...... to acquire geometrically and chromatically corrected images in homogeneous and diffuse illumination, so images can be compared over time. The proposed segmentation algorithm combines the information provided by all the spectral bands to segment the different regions of interest. Three experiments...... are conducted to show the ability of the system to acquire highly precise, reproducible and standardized multi-spectral images and to show its applicabilities in different situations....

  16. Image and Sensor Data Processing for Target Acquisition and Recognition.

    Science.gov (United States)

    1980-11-01

    reprisontativo d’images d’antratne- mont dout il connait la viriti terrain . Pour chacune des cibles do cec images, lordinateur calculera les n paramitres...l’objet, glissement limitd A sa lergeur. DOaprds las rdsultets obtenus jusqu’A meintenent, nous navons pas observE de glissement impor- tant et ATR> I TR...AEROSPACE RESEARCH AND DEVELOPMENT (ORGANISATION DU TRAITE DE L’ATLANTIQUE NORD) AGARDonferenceJoceedin io.290 IMAGE AND SENSOR DATA PROCESSING FOR TARGET

  17. Use of an Image Acquisition Stabilizer Improves Sidestream Dark Field Imaging of the Serosa during Open Gastrointestinal Surgery.

    Science.gov (United States)

    de Bruin, Anthonius F J; Tavy, Arthur; van der Sloot, Koene; Smits, Anke; Van Ramshorst, Bert; Boerma, Christiaan E; Kars, Peter; Noordzij, Peter G; Boerma, Djamila; van Iterson, Mat

    2016-01-01

    To investigate whether an image acquisition stabilizer (IAS) mounted on the sidestream dark field camera (SDF) during gastrointestinal surgery improves image stability and acquisition. Serosal SDF imaging was compared with SDF imaging combined with an IAS (SDF + IAS) during gastrointestinal surgery. Stability was assessed as the image drift in pixels and the time to obtain stable images. The success rate was determined as the percentage of analyzable images after recording. The effect of negative pressure from the IAS was determined during single-spot measurements and by comparing microvascular parameters between groups. Data are presented as mean ± SD. Sixty serosal measurements were performed per group; 87% were successful in the SDF group and 100% in the SDF + IAS group (p = 0.003). Image drift in the SDF group was 148 ± 36 versus 55 ± 15 pixels in the SDF + IAS group; p camera during serosal microvascular assessment improves the success rate of image acquisition and stability and reduces the time to stable image with no effect on the microcirculation. © 2016 S. Karger AG, Basel.

  18. Rapid prototyping of biomimetic vascular phantoms for hyperspectral reflectance imaging.

    Science.gov (United States)

    Ghassemi, Pejhman; Wang, Jianting; Melchiorri, Anthony J; Ramella-Roman, Jessica C; Mathews, Scott A; Coburn, James C; Sorg, Brian S; Chen, Yu; Pfefer, T Joshua

    2015-01-01

    The emerging technique of rapid prototyping with three-dimensional (3-D) printers provides a simple yet revolutionary method for fabricating objects with arbitrary geometry. The use of 3-D printing for generating morphologically biomimetic tissue phantoms based on medical images represents a potentially major advance over existing phantom approaches. Toward the goal of image-defined phantoms, we converted a segmented fundus image of the human retina into a matrix format and edited it to achieve a geometry suitable for printing. Phantoms with vessel-simulating channels were then printed using a photoreactive resin providing biologically relevant turbidity, as determined by spectrophotometry. The morphology of printed vessels was validated by x-ray microcomputed tomography. Channels were filled with hemoglobin (Hb) solutions undergoing desaturation, and phantoms were imaged with a near-infrared hyperspectral reflectance imaging system. Additionally, a phantom was printed incorporating two disjoint vascular networks at different depths, each filled with Hb solutions at different saturation levels. Light propagation effects noted during these measurements—including the influence of vessel density and depth on Hb concentration and saturation estimates, and the effect of wavelength on vessel visualization depth—were evaluated. Overall, our findings indicated that 3-D-printed biomimetic phantoms hold significant potential as realistic and practical tools for elucidating light–tissue interactions and characterizing biophotonic system performance.

  19. Adaptive Robotic Welding Using A Rapid Image Pre-Processor

    Science.gov (United States)

    Dufour, M.; Begin, G.

    1984-02-01

    The rapid pre-processor initially developed by NRCC and Leigh Instruments Inc. as part of the visual aid system of the space shuttle arm 1 has been adapted to perform real time seam tracking of multipass butt weld and other adaptive welding functions. The weld preparation profile is first enhanced by a projected laser target formed by a line and dots. A standard TV camera is used to observe the target image at an angle. Displacement and distorsion of the target image on a monitor are simple functions of the preparation surface distance and shape respectively. Using the video signal, the pre-processor computes in real time the area and first moments of the white level figure contained within four independent rectangular windows in the field of view of the camera. The shape, size, and position of each window can be changed dynamically for each successive image at the standard 30 images/sec rate, in order to track some target image singularities. Visual sensing and welding are done simultaneously. As an example, it is shown that thin sheet metal welding can be automated using a single window for seam tracking, gap width measurement and torch height estimation. Using a second window, measurement of sheet misalignment and their orientation in space were also achieved. The system can be used at welding speed of up to 1 m/min. Simplicity, speed and effectiveness are the main advantages of this system.

  20. Dual-scanning optical coherence elastography for rapid imaging of two tissue volumes (Conference Presentation)

    Science.gov (United States)

    Fang, Qi; Frewer, Luke; Wijesinghe, Philip; Hamzah, Juliana; Ganss, Ruth; Allen, Wes M.; Sampson, David D.; Curatolo, Andrea; Kennedy, Brendan F.

    2017-02-01

    In many applications of optical coherence elastography (OCE), it is necessary to rapidly acquire images in vivo, or within intraoperative timeframes, over fields-of-view far greater than can be achieved in one OCT image acquisition. For example, tumour margin assessment in breast cancer requires acquisition over linear dimensions of 4-5 centimetres in under 20 minutes. However, the majority of existing techniques are not compatible with these requirements, which may present a hurdle to the effective translation of OCE. To increase throughput, we have designed and developed an OCE system that simultaneously captures two 3D elastograms from opposite sides of a sample. The optical system comprises two interferometers: a common-path interferometer on one side of the sample and a dual-arm interferometer on the other side. This optical system is combined with scanning mechanisms and compression loading techniques to realize dual-scanning OCE. The optical signals scattered from two volumes are simultaneously detected on a single spectrometer by depth-encoding the interference signal from each interferometer. To demonstrate dual-scanning OCE, we performed measurements on tissue-mimicking phantoms containing rigid inclusions and freshly isolated samples of murine hepatocellular carcinoma, highlighting the use of this technique to visualise 3D tumour stiffness. These findings indicate that our technique holds promise for in vivo and intraoperative applications.

  1. Upconversion applied for mid-IR hyperspectral image acquisition

    DEFF Research Database (Denmark)

    Tidemand-Lichtenberg, Peter; Kehlet, Louis Martinus; Sanders, Nicolai Højer

    2015-01-01

    Different schemes for upconversion mid-IR hyperspectral imaging is implemented and compared in terms of spectral coverage, spectral resolution, speed and noise. Phasematch scanning and scanning of the object within the field of view is considered....

  2. Quantitative assessment of the impact of biomedical image acquisition on the results obtained from image analysis and processing.

    Science.gov (United States)

    Koprowski, Robert

    2014-07-04

    Dedicated, automatic algorithms for image analysis and processing are becoming more and more common in medical diagnosis. When creating dedicated algorithms, many factors must be taken into consideration. They are associated with selecting the appropriate algorithm parameters and taking into account the impact of data acquisition on the results obtained. An important feature of algorithms is the possibility of their use in other medical units by other operators. This problem, namely operator's (acquisition) impact on the results obtained from image analysis and processing, has been shown on a few examples. The analysed images were obtained from a variety of medical devices such as thermal imaging, tomography devices and those working in visible light. The objects of imaging were cellular elements, the anterior segment and fundus of the eye, postural defects and others. In total, almost 200'000 images coming from 8 different medical units were analysed. All image analysis algorithms were implemented in C and Matlab. For various algorithms and methods of medical imaging, the impact of image acquisition on the results obtained is different. There are different levels of algorithm sensitivity to changes in the parameters, for example: (1) for microscope settings and the brightness assessment of cellular elements there is a difference of 8%; (2) for the thyroid ultrasound images there is a difference in marking the thyroid lobe area which results in a brightness assessment difference of 2%. The method of image acquisition in image analysis and processing also affects: (3) the accuracy of determining the temperature in the characteristic areas on the patient's back for the thermal method - error of 31%; (4) the accuracy of finding characteristic points in photogrammetric images when evaluating postural defects - error of 11%; (5) the accuracy of performing ablative and non-ablative treatments in cosmetology - error of 18% for the nose, 10% for the cheeks, and 7% for the

  3. 3D imaging acquisition, modeling, and prototyping for facial defects reconstruction

    Science.gov (United States)

    Sansoni, Giovanna; Trebeschi, Marco; Cavagnini, Gianluca; Gastaldi, Giorgio

    2009-01-01

    A novel approach that combines optical three-dimensional imaging, reverse engineering (RE) and rapid prototyping (RP) for mold production in the prosthetic reconstruction of facial prostheses is presented. A commercial laser-stripe digitizer is used to perform the multiview acquisition of the patient's face; the point clouds are aligned and merged in order to obtain a polygonal model, which is then edited to sculpture the virtual prothesis. Two physical models of both the deformed face and the 'repaired' face are obtained: they differ only in the defect zone. Depending on the material used for the actual prosthesis, the two prototypes can be used either to directly cast the final prosthesis or to fabricate the positive wax pattern. Two case studies are presented, referring to prostetic reconstructions of an eye and of a nose. The results demonstrate the advantages over conventional techniques as well as the improvements with respect to known automated manufacturing techniques in the mold construction. The proposed method results into decreased patient's disconfort, reduced dependence on the anaplasthologist skill, increased repeatability and efficiency of the whole process.

  4. System and method for optical fiber based image acquisition suitable for use in turbine engines

    Science.gov (United States)

    Baleine, Erwan; A V, Varun; Zombo, Paul J.; Varghese, Zubin

    2017-05-16

    A system and a method for image acquisition suitable for use in a turbine engine are disclosed. Light received from a field of view in an object plane is projected onto an image plane through an optical modulation device and is transferred through an image conduit to a sensor array. The sensor array generates a set of sampled image signals in a sensing basis based on light received from the image conduit. Finally, the sampled image signals are transformed from the sensing basis to a representation basis and a set of estimated image signals are generated therefrom. The estimated image signals are used for reconstructing an image and/or a motion-video of a region of interest within a turbine engine.

  5. Development of rapid methods for relaxation time mapping and motion estimation using magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gilani, Syed Irtiza Ali

    2008-09-15

    Recent technological developments in the field of magnetic resonance imaging have resulted in advanced techniques that can reduce the total time to acquire images. For applications such as relaxation time mapping, which enables improved visualisation of in vivo structures, rapid imaging techniques are highly desirable. TAPIR is a Look- Locker-based sequence for high-resolution, multislice T{sub 1} relaxation time mapping. Despite the high accuracy and precision of TAPIR, an improvement in the k-space sampling trajectory is desired to acquire data in clinically acceptable times. In this thesis, a new trajectory, termed line-sharing, is introduced for TAPIR that can potentially reduce the acquisition time by 40 %. Additionally, the line-sharing method was compared with the GRAPPA parallel imaging method. These methods were employed to reconstruct time-point images from the data acquired on a 4T high-field MR research scanner. Multislice, multipoint in vivo results obtained using these methods are presented. Despite improvement in acquisition speed, through line-sharing, for example, motion remains a problem and artefact-free data cannot always be obtained. Therefore, in this thesis, a rapid technique is introduced to estimate in-plane motion. The presented technique is based on calculating the in-plane motion parameters, i.e., translation and rotation, by registering the low-resolution MR images. The rotation estimation method is based on the pseudo-polar FFT, where the Fourier domain is composed of frequencies that reside in an oversampled set of non-angularly, equispaced points. The essence of the method is that unlike other Fourier-based registration schemes, the employed approach does not require any interpolation to calculate the pseudo-polar FFT grid coordinates. Translation parameters are estimated by the phase correlation method. However, instead of two-dimensional analysis of the phase correlation matrix, a low complexity subspace identification of the phase

  6. Rapid Acquisition and Fielding for Information Assurance and Cyber Security in the Navy

    Science.gov (United States)

    2012-01-01

    Com- mand and Control (DJC2); Norman Beebe , IA contractor handling C&A for DJC2; Leo Martinez, Booz Allen Hamilton, PEO C4I and Space Support; Marianne... Leslie , Defense Acquisition University, “Contracting in a Changing Environment,” briefing, undated. Dillard, John T., and David N. Ford, From

  7. Page 1 Image acquisition & surface reconstruction using active ...

    Indian Academy of Sciences (India)

    and equipped with Vicon V17.5–105M motorized zoom lenses. High-precision stepper-motor rotational units are used to control independent pan, tilt, and vergence angles. The imaging system is controlled by a Sun Microsystems 3/160 workstation. 4.1 Implementation details. For the left and the right cameras, calibrated ...

  8. Dual camera system for acquisition of high resolution images

    Science.gov (United States)

    Papon, Jeremie A.; Broussard, Randy P.; Ives, Robert W.

    2007-02-01

    Video surveillance is ubiquitous in modern society, but surveillance cameras are severely limited in utility by their low resolution. With this in mind, we have developed a system that can autonomously take high resolution still frame images of moving objects. In order to do this, we combine a low resolution video camera and a high resolution still frame camera mounted on a pan/tilt mount. In order to determine what should be photographed (objects of interest), we employ a hierarchical method which first separates foreground from background using a temporal-based median filtering technique. We then use a feed-forward neural network classifier on the foreground regions to determine whether the regions contain the objects of interest. This is done over several frames, and a motion vector is deduced for the object. The pan/tilt mount then focuses the high resolution camera on the next predicted location of the object, and an image is acquired. All components are controlled through a single MATLAB graphical user interface (GUI). The final system we present will be able to detect multiple moving objects simultaneously, track them, and acquire high resolution images of them. Results will demonstrate performance tracking and imaging varying numbers of objects moving at different speeds.

  9. Scheduling algorithms for rapid imaging using agile Cubesat constellations

    Science.gov (United States)

    Nag, Sreeja; Li, Alan S.; Merrick, James H.

    2018-02-01

    Distributed Space Missions such as formation flight and constellations, are being recognized as important Earth Observation solutions to increase measurement samples over space and time. Cubesats are increasing in size (27U, ∼40 kg in development) with increasing capabilities to host imager payloads. Given the precise attitude control systems emerging in the commercial market, Cubesats now have the ability to slew and capture images within short notice. We propose a modular framework that combines orbital mechanics, attitude control and scheduling optimization to plan the time-varying, full-body orientation of agile Cubesats in a constellation such that they maximize the number of observed images and observation time, within the constraints of Cubesat hardware specifications. The attitude control strategy combines bang-bang and PD control, with constraints such as power consumption, response time, and stability factored into the optimality computations and a possible extension to PID control to account for disturbances. Schedule optimization is performed using dynamic programming with two levels of heuristics, verified and improved upon using mixed integer linear programming. The automated scheduler is expected to run on ground station resources and the resultant schedules uplinked to the satellites for execution, however it can be adapted for onboard scheduling, contingent on Cubesat hardware and software upgrades. The framework is generalizable over small steerable spacecraft, sensor specifications, imaging objectives and regions of interest, and is demonstrated using multiple 20 kg satellites in Low Earth Orbit for two case studies - rapid imaging of Landsat's land and coastal images and extended imaging of global, warm water coral reefs. The proposed algorithm captures up to 161% more Landsat images than nadir-pointing sensors with the same field of view, on a 2-satellite constellation over a 12-h simulation. Integer programming was able to verify that

  10. Monitoring of HTS compound library quality via a high-resolution image acquisition and processing instrument.

    Science.gov (United States)

    Baillargeon, Pierre; Scampavia, Louis; Einsteder, Ross; Hodder, Peter

    2011-06-01

    This report presents the high-resolution image acquisition and processing instrument for compound management applications (HIAPI-CM). The HIAPI-CM combines imaging spectroscopy and machine-vision analysis to perform rapid assessment of high-throughput screening (HTS) compound library quality. It has been customized to detect and classify typical artifacts found in HTS compound library microtiter plates (MTPs). These artifacts include (1) insufficient volume of liquid compound sample, (2) compound precipitation, and (3) colored compounds that interfere with HTS assay detection format readout. The HIAPI-CM is also configured to automatically query and compare its analysis results to data stored in a LIMS or corporate database, aiding in the detection of compound registration errors. To demonstrate its capabilities, several compound plates (n=5760 wells total) containing different artifacts were measured via automated HIAPI-CM analysis, and results compared with those obtained by manual (visual) inspection. In all cases, the instrument demonstrated high fidelity (99.8% empty wells; 100.1% filled wells; 94.4% for partially filled wells; 94.0% for wells containing colored compounds), and in the case of precipitate detection, the HIAPI-CM results significantly exceeded the fidelity of visual observations (220.0%). As described, the HIAPI-CM allows for noninvasive, nondestructive MTP assessment with a diagnostic throughput of about 1min per plate, reducing analytical expenses and improving the quality and stewardship of HTS compound libraries. Copyright © 2011 Society for Laboratory Automation and Screening. Published by Elsevier Inc. All rights reserved.

  11. Full-field wrist pulse signal acquisition and analysis by 3D Digital Image Correlation

    Science.gov (United States)

    Xue, Yuan; Su, Yong; Zhang, Chi; Xu, Xiaohai; Gao, Zeren; Wu, Shangquan; Zhang, Qingchuan; Wu, Xiaoping

    2017-11-01

    Pulse diagnosis is an essential part in four basic diagnostic methods (inspection, listening, inquiring and palpation) in traditional Chinese medicine, which depends on longtime training and rich experience, so computerized pulse acquisition has been proposed and studied to ensure the objectivity. To imitate the process that doctors using three fingertips with different pressures to feel fluctuations in certain areas containing three acupoints, we established a five dimensional pulse signal acquisition system adopting a non-contacting optical metrology method, 3D digital image correlation, to record the full-field displacements of skin fluctuations under different pressures. The system realizes real-time full-field vibration mode observation with 10 FPS. The maximum sample frequency is 472 Hz for detailed post-processing. After acquisition, the signals are analyzed according to the amplitude, pressure, and pulse wave velocity. The proposed system provides a novel optical approach for digitalizing pulse diagnosis and massive pulse signal data acquisition for various types of patients.

  12. Troubleshooting digital macro photography for image acquisition and the analysis of biological samples.

    Science.gov (United States)

    Liepinsh, Edgars; Kuka, Janis; Dambrova, Maija

    2013-01-01

    For years, image acquisition and analysis have been an important part of life science experiments to ensure the adequate and reliable presentation of research results. Since the development of digital photography and digital planimetric methods for image analysis approximately 20 years ago, new equipment and technologies have emerged, which have increased the quality of image acquisition and analysis. Different techniques are available to measure the size of stained tissue samples in experimental animal models of disease; however, the most accurate method is digital macro photography with software that is based on planimetric analysis. In this study, we described the methodology for the preparation of infarcted rat heart and brain tissue samples before image acquisition, digital macro photography techniques and planimetric image analysis. These methods are useful in the macro photography of biological samples and subsequent image analysis. In addition, the techniques that are described in this study include the automated analysis of digital photographs to minimize user input and exclude the risk of researcher-generated errors or bias during image analysis. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. MR imaging of ore for heap bioleaching studies using pure phase encode acquisition methods

    Science.gov (United States)

    Fagan, Marijke A.; Sederman, Andrew J.; Johns, Michael L.

    2012-03-01

    Various MRI techniques were considered with respect to imaging of aqueous flow fields in low grade copper ore. Spin echo frequency encoded techniques were shown to produce unacceptable image distortions which led to pure phase encoded techniques being considered. Single point imaging multiple point acquisition (SPI-MPA) and spin echo single point imaging (SESPI) techniques were applied. By direct comparison with X-ray tomographic images, both techniques were found to be able to produce distortion-free images of the ore packings at 2 T. The signal to noise ratios (SNRs) of the SESPI images were found to be superior to SPI-MPA for equal total acquisition times; this was explained based on NMR relaxation measurements. SESPI was also found to produce suitable images for a range of particles sizes, whereas SPI-MPA SNR deteriorated markedly as particles size was reduced. Comparisons on a 4.7 T magnet showed significant signal loss from the SPI-MPA images, the effect of which was accentuated in the case of unsaturated flowing systems. Hence it was concluded that SESPI was the most robust imaging method for the study of copper ore heap leaching hydrology.

  14. USMC Contingency Contracting Force: An Analysis of Transient Officers in a Rapidly Changing Acquisition Environment

    Science.gov (United States)

    2016-06-01

    customers to alleviate problems associated to requirements definition . • Contract Documentation With Contract Documentation containing 29 total reports...and skills needed to manage the department’s acquisition system” (2008, p. 268). Relating back to the CCF, an overpopulation of lieutenant colonels...questions are more broad-brushed than definitive . I graduated NPS in 2003 and with the exception of a 2-year command tour I have been in the MOS and have

  15. Bulk density estimation using a 3-dimensional image acquisition and analysis system

    Directory of Open Access Journals (Sweden)

    Heyduk Adam

    2016-01-01

    Full Text Available The paper presents a concept of dynamic bulk density estimation of a particulate matter stream using a 3-d image analysis system and a conveyor belt scale. A method of image acquisition should be adjusted to the type of scale. The paper presents some laboratory results of static bulk density measurements using the MS Kinect time-of-flight camera and OpenCV/Matlab software. Measurements were made for several different size classes.

  16. Mapping soil heterogeneity using RapidEye satellite images

    Science.gov (United States)

    Piccard, Isabelle; Eerens, Herman; Dong, Qinghan; Gobin, Anne; Goffart, Jean-Pierre; Curnel, Yannick; Planchon, Viviane

    2016-04-01

    In the frame of BELCAM, a project funded by the Belgian Science Policy Office (BELSPO), researchers from UCL, ULg, CRA-W and VITO aim to set up a collaborative system to develop and deliver relevant information for agricultural monitoring in Belgium. The main objective is to develop remote sensing methods and processing chains able to ingest crowd sourcing data, provided by farmers or associated partners, and to deliver in return relevant and up-to-date information for crop monitoring at the field and district level based on Sentinel-1 and -2 satellite imagery. One of the developments within BELCAM concerns an automatic procedure to detect soil heterogeneity within a parcel using optical high resolution images. Such heterogeneity maps can be used to adjust farming practices according to the detected heterogeneity. This heterogeneity may for instance be caused by differences in mineral composition of the soil, organic matter content, soil moisture or soil texture. Local differences in plant growth may be indicative for differences in soil characteristics. As such remote sensing derived vegetation indices may be used to reveal soil heterogeneity. VITO started to delineate homogeneous zones within parcels by analyzing a series of RapidEye images acquired in 2015 (as a precursor for Sentinel-2). Both unsupervised classification (ISODATA, K-means) and segmentation techniques were tested. Heterogeneity maps were generated from images acquired at different moments during the season (13 May, 30 June, 17 July, 31 August, 11 September and 1 November 2015). Tests were performed using blue, green, red, red edge and NIR reflectances separately and using derived indices such as NDVI, fAPAR, CIrededge, NDRE2. The results for selected winter wheat, maize and potato fields were evaluated together with experts from the collaborating agricultural research centers. For a few fields UAV images and/or yield measurements were available for comparison.

  17. Development of an image acquisition system for hand vein based on an embedded system

    Science.gov (United States)

    Li, Xiuyan; Liu, Tiegen; Wang, Yunxin; Yuan, Chenhu; Deng, Shichao

    2009-07-01

    As one kind of the latest forms of biometrics, the human hand vein recognition utilizes a state-of-the-art recognition algorithm based on unique veins and capillaries found on human dorsal hand, which possesses the advantages such as well anti-falsification and high noise immunity. For the hand vein recognition, the most important premise is acquiring the high quality hand vein image. According to the special effect of human hand vein on the near infrared (NIR), when a hand is scanned by an image sensor, the vein pattern appears darker than its surroundings. Depending on this characteristic, the NIR light source was utilized to illuminate the image acquisition system for hand vein. And the optimal parameters of light source were chosen and the light source with high uniformity illuminance was manufactured to acquire the more clear hand vein image. Simultaneously, for the purpose of system miniaturization and design flexibility, the embedded image acquisition system for hand vein was designed based on the technology of system on programmable chip (SOPC). FPGA and CMOS image sensor were taken as the core components in the system, and the hardware of acquisition module is realized by configuring NiosII soft-core CPU and some corresponding interface modules on a FPGA. The software was developed by using the NiosII IDE to realize the initialization control to CMOS image sensor and collection, storage and transmission for the image data gathered from CMOS. Then the collected hand vein image was simply preprocessed, which further improved the image quality. Through experiments, the results indicated that this system could obtain the hand vein image with high performance, and it supplied the embedded development platform for hand vein recognition simultaneously. It was significant to develop the hand vein recognition system with small size and high speed.

  18. In-Situ Imaging of Particles during Rapid Thermite Deflagrations

    Science.gov (United States)

    Grapes, Michael; Reeves, Robert; Densmore, John; Fezzaa, Kamel; van Buuren, Tony; Willey, Trevor; Sullivan, Kyle

    2017-06-01

    The dynamic behavior of rapidly deflagrating thermites is a highly complex process involving rapid decomposition, melting, and outgassing of intermediate and/or product gases. Few experimental techniques are capable of probing these phenomena in situ due to the small length and time scales associated with the reaction. Here we use a recently developed extended burn tube test, where we initiate a small pile of thermite on the closed end of a clear acrylic tube. The length of the tube is sufficient to fully contain the reaction as it proceeds and flows entrained particles down the tube. This experiment was brought to the Advanced Photon Source, and the particle formation was X-ray imaged at various positions down the tube. Several formulations, as well as formulation parameters were varied to investigate the size and morphology of the particles, as well as to look for dynamic behavior attributed to the reaction. In all cases, we see evidence of particle coalescence and condensed-phase interfacial reactions. The results improve our understanding of the procession of reactants to products in these systems. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-691140.

  19. Digital image capture and rapid prototyping of the maxillofacial defect.

    Science.gov (United States)

    Sabol, Jennifer V; Grant, Gerald T; Liacouras, Peter; Rouse, Stephen

    2011-06-01

    In order to restore an extraoral maxillofacial defect, a moulage impression is commonly made with traditional impression materials. This technique has some disadvantages, including distortion of the site due to the weight of the impression material, changes in tissue location with modifications of the patient position, and the length of time and discomfort for the patient due to the impression procedure and materials used. The use of the commercially available 3dMDface™ System creates 3D images of soft tissues to form an anatomically accurate 3D surface image. Rapid prototyping converts the virtual designs from the 3dMDface™ System into a physical model by converting the data to a ZPrint (ZPR) CAD format file and a stereolithography (STL) file. The data, in conjunction with a Zprinter(®) 450 or a Stereolithography Apparatus (SLA), can be used to fabricate a model for prosthesis fabrication, without the disadvantages of the standard moulage technique. This article reviews this technique and how it can be applied to maxillofacial prosthetics. © 2011 by The American College of Prosthodontists.

  20. Rapid acquisition of HPV around the time of sexual debut in adolescent girls in Tanzania.

    Science.gov (United States)

    Houlihan, Catherine F; Baisley, Kathy; Bravo, Ignacio G; Kapiga, Saidi; de Sanjosé, Silvia; Changalucha, John; Ross, David A; Hayes, Richard J; Watson-Jones, Deborah

    2016-06-01

    No reports exist on genotype-specific human papillomavirus (HPV) acquisition in girls after first sex in sub-Saharan Africa, despite high HPV prevalence and cervical cancer incidence. We followed 503 HP-unvaccinated girls aged 15-16 years in Mwanza, Tanzania, 3-monthly for 18 months with interviews and self-administered vaginal swabs. Swabs were tested for 13 higHRisk and 24 low-risk HPV genotypes. Incidence, clearance and duration of overall HPV and genotype-specific infections were calculated and associated factors evaluated. A total of 106 participants reported first sex prior to enrolment (N = 29) or during follow-up (N = 77). One was HIV-positive at the final visit. The remaining 105 girls contributed 323 adequate specimens. Incidence of any new HPV genotype was 225/100 person-years (pys), and incidence of vaccine types HPV-6, -11, -16 and -18 were 12, 2, 2 and 7/100 pys, respectively. Reporting sex in the past 3 months and knowing the most recent sexual partner for a longer period before sex were associated with HPV acquisition. Median time from reported sexual debut to first HPVinfection was 5 months, and infection duration was 6 months. This is the first description of HPV acquisition after first sex in sub-Saharan Africa where the incidence of cervical cancer is amongst the highest in the world. HPV incidence was very high after first sex, including some vaccine genotypes, and infection duration was short. This very high HPV incidence may help explain high cervical cancer rates, and supports recommendations that the HPV vaccine should be given to girls before first sex. © The Author 2016; Published by Oxford University Press on behalf of the International Epidemiological Association.

  1. Magnetic resonance imaging acquisition techniques intended to decrease movement artefact in paediatric brain imaging: a systematic review

    Energy Technology Data Exchange (ETDEWEB)

    Woodfield, Julie [University of Edinburgh, Child Life and Health, Edinburgh (United Kingdom); Kealey, Susan [Western General Hospital, Department of Neuroradiology, Edinburgh (United Kingdom)

    2015-08-15

    Attaining paediatric brain images of diagnostic quality can be difficult because of young age or neurological impairment. The use of anaesthesia to reduce movement in MRI increases clinical risk and cost, while CT, though faster, exposes children to potentially harmful ionising radiation. MRI acquisition techniques that aim to decrease movement artefact may allow diagnostic paediatric brain imaging without sedation or anaesthesia. We conducted a systematic review to establish the evidence base for ultra-fast sequences and sequences using oversampling of k-space in paediatric brain MR imaging. Techniques were assessed for imaging time, occurrence of movement artefact, the need for sedation, and either image quality or diagnostic accuracy. We identified 24 relevant studies. We found that ultra-fast techniques had shorter imaging acquisition times compared to standard MRI. Techniques using oversampling of k-space required equal or longer imaging times than standard MRI. Both ultra-fast sequences and those using oversampling of k-space reduced movement artefact compared with standard MRI in unsedated children. Assessment of overall diagnostic accuracy was difficult because of the heterogeneous patient populations, imaging indications, and reporting methods of the studies. In children with shunt-treated hydrocephalus there is evidence that ultra-fast MRI is sufficient for the assessment of ventricular size. (orig.)

  2. Rapid acquisition of HPV around the time of sexual debut in adolescent girls in Tanzania.

    OpenAIRE

    Houlihan, CF; Baisley, K; Bravo, IG; Kapiga, S; de Sanjosé, S; Changalucha, J; Ross, DA; Hayes, RJ; Watson-Jones, D

    2016-01-01

    Background: No reports exist on genotype-specific human papillomavirus (HPV) acquisition in girls after first sex in sub-Saharan Africa, despite high HPV prevalence and cervical cancer incidence. Methods: We followed 503?HP-unvaccinated girls aged 15-16 years in Mwanza, Tanzania, 3-monthly for 18 months with interviews and self-administered vaginal swabs. Swabs were tested for 13 higHRisk and 24 low-risk HPV genotypes. Incidence, clearance and duration of overall HPV and genotype-specific inf...

  3. Automated system for acquisition and image processing for the control and monitoring boned nopal

    Science.gov (United States)

    Luevano, E.; de Posada, E.; Arronte, M.; Ponce, L.; Flores, T.

    2013-11-01

    This paper describes the design and fabrication of a system for acquisition and image processing to control the removal of thorns nopal vegetable (Opuntia ficus indica) in an automated machine that uses pulses of a laser of Nd: YAG. The areolas, areas where thorns grow on the bark of the Nopal, are located applying segmentation algorithms to the images obtained by a CCD. Once the position of the areolas is known, coordinates are sent to a motors system that controls the laser to interact with all areolas and remove the thorns of the nopal. The electronic system comprises a video decoder, memory for image and software storage, and digital signal processor for system control. The firmware programmed tasks on acquisition, preprocessing, segmentation, recognition and interpretation of the areolas. This system achievement identifying areolas and generating table of coordinates of them, which will be send the motor galvo system that controls the laser for removal

  4. Effects of acquisition time and reconstruction algorithm on image quality, quantitative parameters, and clinical interpretation of myocardial perfusion imaging

    DEFF Research Database (Denmark)

    Enevoldsen, Lotte H; Menashi, Changez A K; Andersen, Ulrik B

    2013-01-01

    -RR) and for quantitative analysis (FT-FBP, HT-FBP, and HT-RR). The datasets were analyzed using commercially available QGS/QPS software and read by two observers evaluating image quality and clinical interpretation. Image quality was assessed on a 10-cm visual analog scale score. RESULTS: HT imaging was associated......BACKGROUND: Recently introduced iterative reconstruction algorithms with resolution recovery (RR) and noise-reduction technology seem promising for reducing scan time or radiation dose without loss of image quality. However, the relative effects of reduced acquisition time and reconstruction...... with loss of image quality that was compensated for by RR reconstruction. HT imaging was also associated with increasing perfusion defect extents, an effect more pronounced using RR than FBP reconstruction. Compared to standard FT-FBP, HT-RR significantly reduced left ventricular volumes whereas HT...

  5. Whole heart coronary imaging with flexible acquisition window and trigger delay.

    Directory of Open Access Journals (Sweden)

    Keigo Kawaji

    Full Text Available Coronary magnetic resonance imaging (MRI requires a correctly timed trigger delay derived from a scout cine scan to synchronize k-space acquisition with the quiescent period of the cardiac cycle. However, heart rate changes between breath-held cine and free-breathing coronary imaging may result in inaccurate timing errors. Additionally, the determined trigger delay may not reflect the period of minimal motion for both left and right coronary arteries or different segments. In this work, we present a whole-heart coronary imaging approach that allows flexible selection of the trigger delay timings by performing k-space sampling over an enlarged acquisition window. Our approach addresses coronary motion in an interactive manner by allowing the operator to determine the temporal window with minimal cardiac motion for each artery region. An electrocardiogram-gated, k-space segmented 3D radial stack-of-stars sequence that employs a custom rotation angle is developed. An interactive reconstruction and visualization platform is then employed to determine the subset of the enlarged acquisition window for minimal coronary motion. Coronary MRI was acquired on eight healthy subjects (5 male, mean age = 37 ± 18 years, where an enlarged acquisition window of 166-220 ms was set 50 ms prior to the scout-derived trigger delay. Coronary visualization and sharpness scores were compared between the standard 120 ms window set at the trigger delay, and those reconstructed using a manually adjusted window. The proposed method using manual adjustment was able to recover delineation of five mid and distal right coronary artery regions that were otherwise not visible from the standard window, and the sharpness scores improved in all coronary regions using the proposed method. This paper demonstrates the feasibility of a whole-heart coronary imaging approach that allows interactive selection of any subset of the enlarged acquisition window for a tailored reconstruction

  6. Sparse-sampling with time-encoded (TICO) stimulated Raman scattering for fast image acquisition

    Science.gov (United States)

    Hakert, Hubertus; Eibl, Matthias; Karpf, Sebastian; Huber, Robert

    2017-07-01

    Modern biomedical imaging modalities aim to provide researchers a multimodal contrast for a deeper insight into a specimen under investigation. A very promising technique is stimulated Raman scattering (SRS) microscopy, which can unveil the chemical composition of a sample with a very high specificity. Although the signal intensities are enhanced manifold to achieve a faster acquisition of images if compared to standard Raman microscopy, there is a trade-off between specificity and acquisition speed. Commonly used SRS concepts either probe only very few Raman transitions as the tuning of the applied laser sources is complicated or record whole spectra with a spectrometer based setup. While the first approach is fast, it reduces the specificity and the spectrometer approach records whole spectra -with energy differences where no Raman information is present-, which limits the acquisition speed. Therefore, we present a new approach based on the TICO-Raman concept, which we call sparse-sampling. The TICO-sparse-sampling setup is fully electronically controllable and allows probing of only the characteristic peaks of a Raman spectrum instead of always acquiring a whole spectrum. By reducing the spectral points to the relevant peaks, the acquisition time can be greatly reduced compared to a uniformly, equidistantly sampled Raman spectrum while the specificity and the signal to noise ratio (SNR) are maintained. Furthermore, all laser sources are completely fiber based. The synchronized detection enables a full resolution of the Raman signal, whereas the analogue and digital balancing allows shot noise limited detection. First imaging results with polystyrene (PS) and polymethylmethacrylate (PMMA) beads confirm the advantages of TICO sparse-sampling. We achieved a pixel dwell time as low as 35 μs for an image differentiating both species. The mechanical properties of the applied voice coil stage for scanning the sample currently limits even faster acquisition.

  7. A digital data acquisition scheme for SPECT and PET small animal imaging detectors for Theranostic applications

    Science.gov (United States)

    Georgiou, M.; Fysikopoulos, E.; Loudos, G.

    2017-11-01

    Nanoparticle based drug delivery is considered as a new, promising technology for the efficient treatment of various diseases. When nanoparticles are radiolabelled it is possible to image them, using molecular imaging techniques. The use of magnetic nanoparticles in hyperthermia is one of the most promising nanomedicine directions and requires the accurate, non-invasive, monitoring of temperature increase and drug release. The combination of imaging and therapy has opened the very promising Theranostics domain. In this work, we present a digital data acquisition scheme for nuclear medicine dedicated detectors for Theranostic applications.

  8. A review of breast tomosynthesis. Part I. The image acquisition process

    Energy Technology Data Exchange (ETDEWEB)

    Sechopoulos, Ioannis [Department of Radiology and Imaging Sciences, Hematology and Medical Oncology and Winship Cancer Institute, Emory University, 1701 Upper Gate Drive Northeast, Suite 5018, Atlanta, Georgia 30322 (United States)

    2013-01-15

    Mammography is a very well-established imaging modality for the early detection and diagnosis of breast cancer. However, since the introduction of digital imaging to the realm of radiology, more advanced, and especially tomographic imaging methods have been made possible. One of these methods, breast tomosynthesis, has finally been introduced to the clinic for routine everyday use, with potential to in the future replace mammography for screening for breast cancer. In this two part paper, the extensive research performed during the development of breast tomosynthesis is reviewed, with a focus on the research addressing the medical physics aspects of this imaging modality. This first paper will review the research performed on the issues relevant to the image acquisition process, including system design, optimization of geometry and technique, x-ray scatter, and radiation dose. The companion to this paper will review all other aspects of breast tomosynthesis imaging, including the reconstruction process.

  9. A review of breast tomosynthesis. Part I. The image acquisition process.

    Science.gov (United States)

    Sechopoulos, Ioannis

    2013-01-01

    Mammography is a very well-established imaging modality for the early detection and diagnosis of breast cancer. However, since the introduction of digital imaging to the realm of radiology, more advanced, and especially tomographic imaging methods have been made possible. One of these methods, breast tomosynthesis, has finally been introduced to the clinic for routine everyday use, with potential to in the future replace mammography for screening for breast cancer. In this two part paper, the extensive research performed during the development of breast tomosynthesis is reviewed, with a focus on the research addressing the medical physics aspects of this imaging modality. This first paper will review the research performed on the issues relevant to the image acquisition process, including system design, optimization of geometry and technique, x-ray scatter, and radiation dose. The companion to this paper will review all other aspects of breast tomosynthesis imaging, including the reconstruction process.

  10. A time-efficient acquisition protocol for multipurpose diffusion-weighted microstructural imaging at 7 Tesla.

    Science.gov (United States)

    Sepehrband, Farshid; O'Brien, Kieran; Barth, Markus

    2017-12-01

    Several diffusion-weighted MRI techniques have been developed and validated during the past 2 decades. While offering various neuroanatomical inferences, these techniques differ in their proposed optimal acquisition design, preventing clinicians and researchers benefiting from all potential inference methods, particularly when limited time is available. This study reports an optimal design that enables for a time-efficient diffusion-weighted MRI acquisition scheme at 7 Tesla. The primary audience of this article is the typical end user, interested in diffusion-weighted microstructural imaging at 7 Tesla. We tested b-values in the range of 700 to 3000 s/mm2 with different number of angular diffusion-encoding samples, against a data-driven "gold standard." The suggested design is a protocol with b-values of 1000 and 2500 s/mm2 , with 25 and 50 samples, uniformly distributed over two shells. We also report a range of protocols in which the results of fitting microstructural models to the diffusion-weighted data had high correlation with the gold standard. We estimated minimum acquisition requirements that enable diffusion tensor imaging, higher angular resolution diffusion-weighted imaging, neurite orientation dispersion, and density imaging and white matter tract integrity across whole brain with isotropic resolution of 1.8 mm in less than 11 min. Magn Reson Med 78:2170-2184, 2017. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  11. Quantitative metrics for evaluating parallel acquisition techniques in diffusion tensor imaging at 3 Tesla.

    Science.gov (United States)

    Ardekani, Siamak; Selva, Luis; Sayre, James; Sinha, Usha

    2006-11-01

    Single-shot echo-planar based diffusion tensor imaging is prone to geometric and intensity distortions. Parallel imaging is a means of reducing these distortions while preserving spatial resolution. A quantitative comparison at 3 T of parallel imaging for diffusion tensor images (DTI) using k-space (generalized auto-calibrating partially parallel acquisitions; GRAPPA) and image domain (sensitivity encoding; SENSE) reconstructions at different acceleration factors, R, is reported here. Images were evaluated using 8 human subjects with repeated scans for 2 subjects to estimate reproducibility. Mutual information (MI) was used to assess the global changes in geometric distortions. The effects of parallel imaging techniques on random noise and reconstruction artifacts were evaluated by placing 26 regions of interest and computing the standard deviation of apparent diffusion coefficient and fractional anisotropy along with the error of fitting the data to the diffusion model (residual error). The larger positive values in mutual information index with increasing R values confirmed the anticipated decrease in distortions. Further, the MI index of GRAPPA sequences for a given R factor was larger than the corresponding mSENSE images. The residual error was lowest in the images acquired without parallel imaging and among the parallel reconstruction methods, the R = 2 acquisitions had the least error. The standard deviation, accuracy, and reproducibility of the apparent diffusion coefficient and fractional anisotropy in homogenous tissue regions showed that GRAPPA acquired with R = 2 had the least amount of systematic and random noise and of these, significant differences with mSENSE, R = 2 were found only for the fractional anisotropy index. Evaluation of the current implementation of parallel reconstruction algorithms identified GRAPPA acquired with R = 2 as optimal for diffusion tensor imaging.

  12. Bone surface enhancement in ultrasound images using a new Doppler-based acquisition/processing method

    Science.gov (United States)

    Yang, Xu; Tang, Songyuan; Tasciotti, Ennio; Righetti, Raffaella

    2018-01-01

    Ultrasound (US) imaging has long been considered as a potential aid in orthopedic surgeries. US technologies are safe, portable and do not use radiations. This would make them a desirable tool for real-time assessment of fractures and to monitor fracture healing. However, image quality of US imaging methods in bone applications is limited by speckle, attenuation, shadow, multiple reflections and other imaging artifacts. While bone surfaces typically appear in US images as somewhat ‘brighter’ than soft tissue, they are often not easily distinguishable from the surrounding tissue. Therefore, US imaging methods aimed at segmenting bone surfaces need enhancement in image contrast prior to segmentation to improve the quality of the detected bone surface. In this paper, we present a novel acquisition/processing technique for bone surface enhancement in US images. Inspired by elastography and Doppler imaging methods, this technique takes advantage of the difference between the mechanical and acoustic properties of bones and those of soft tissues to make the bone surface more easily distinguishable in US images. The objective of this technique is to facilitate US-based bone segmentation methods and improve the accuracy of their outcomes. The newly proposed technique is tested both in in vitro and in vivo experiments. The results of these preliminary experiments suggest that the use of the proposed technique has the potential to significantly enhance the detectability of bone surfaces in noisy ultrasound images.

  13. Highly Rapid Amplification-Free and Quantitative DNA Imaging Assay

    Science.gov (United States)

    Klamp, Tobias; Camps, Marta; Nieto, Benjamin; Guasch, Francesc; Ranasinghe, Rohan T.; Wiedemann, Jens; Petrášek, Zdeněk; Schwille, Petra; Klenerman, David; Sauer, Markus

    2013-01-01

    There is an urgent need for rapid and highly sensitive detection of pathogen-derived DNA in a point-of-care (POC) device for diagnostics in hospitals and clinics. This device needs to work in a ‘sample-in-result-out’ mode with minimum number of steps so that it can be completely integrated into a cheap and simple instrument. We have developed a method that directly detects unamplified DNA, and demonstrate its sensitivity on realistically sized 5 kbp target DNA fragments of Micrococcus luteus in small sample volumes of 20 μL. The assay consists of capturing and accumulating of target DNA on magnetic beads with specific capture oligonucleotides, hybridization of complementary fluorescently labeled detection oligonucleotides, and fluorescence imaging on a miniaturized wide-field fluorescence microscope. Our simple method delivers results in less than 20 minutes with a limit of detection (LOD) of ~5 pM and a linear detection range spanning three orders of magnitude. PMID:23677392

  14. Seeing is believing? A beginners' guide to practical pitfalls in image acquisition

    Science.gov (United States)

    North, Alison J.

    2006-01-01

    Imaging can be thought of as the most direct of experiments. You see something; you report what you see. If only things were truly this simple. Modern imaging technology has brought about a revolution in the kinds of questions we can approach, but this comes at the price of increasingly complex equipment. Moreover, in an attempt to market competing systems, the microscopes have often been inappropriately described as easy to use and suitable for near-beginners. Insufficient understanding of the experimental manipulations and equipment set-up leads to the introduction of errors during image acquisition. In this feature, I review some of the most common practical pitfalls faced by researchers during image acquisition, and how they can affect the interpretation of the experimental data. This article is targeted neither to the microscopy gurus who push forward the frontiers of imaging technology nor to my imaging specialist colleagues who may wince at the overly simplistic comments and lack of detail. Instead, this is for beginners who gulp with alarm when they hear the word “confocal pinhole” or sigh as they watch their cells fade and die in front of their very eyes time and time again at the microscope. Take heart, beginners, if microscopes were actually so simple then many people (including myself) would suddenly be out of a job! PMID:16390995

  15. Exploitation of realistic computational anthropomorphic phantoms for the optimization of nuclear imaging acquisition and processing protocols.

    Science.gov (United States)

    Loudos, George K; Papadimitroulas, Panagiotis G; Kagadis, George C

    2014-01-01

    Monte Carlo (MC) simulations play a crucial role in nuclear medical imaging since they can provide the ground truth for clinical acquisitions, by integrating and quantifing all physical parameters that affect image quality. The last decade a number of realistic computational anthropomorphic models have been developed to serve imaging, as well as other biomedical engineering applications. The combination of MC techniques with realistic computational phantoms can provide a powerful tool for pre and post processing in imaging, data analysis and dosimetry. This work aims to create a global database for simulated Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) exams and the methodology, as well as the first elements are presented. Simulations are performed using the well validated GATE opensource toolkit, standard anthropomorphic phantoms and activity distribution of various radiopharmaceuticals, derived from literature. The resulting images, projections and sinograms of each study are provided in the database and can be further exploited to evaluate processing and reconstruction algorithms. Patient studies using different characteristics are included in the database and different computational phantoms were tested for the same acquisitions. These include the XCAT, Zubal and the Virtual Family, which some of which are used for the first time in nuclear imaging. The created database will be freely available and our current work is towards its extension by simulating additional clinical pathologies.

  16. An automatic detection method for the boiler pipe header based on real-time image acquisition

    Science.gov (United States)

    Long, Yi; Liu, YunLong; Qin, Yongliang; Yang, XiangWei; Li, DengKe; Shen, DingJie

    2017-06-01

    Generally, an endoscope is used to test the inner part of the thermal power plants boiler pipe header. However, since the endoscope hose manual operation, the length and angle of the inserted probe cannot be controlled. Additionally, it has a big blind spot observation subject to the length of the endoscope wire. To solve these problems, an automatic detection method for the boiler pipe header based on real-time image acquisition and simulation comparison techniques was proposed. The magnetic crawler with permanent magnet wheel could carry the real-time image acquisition device to complete the crawling work and collect the real-time scene image. According to the obtained location by using the positioning auxiliary device, the position of the real-time detection image in a virtual 3-D model was calibrated. Through comparing of the real-time detection images and the computer simulation images, the defects or foreign matter fall into could be accurately positioning, so as to repair and clean up conveniently.

  17. Research and implementation of video image acquisition and processing based on Java and JMF

    Science.gov (United States)

    Qin, Jinlei; Li, Zheng; Niu, Yuguang

    2012-01-01

    The article put forward a method which had been used for video image acquisition and processing, and a system based on Java media framework (JMF) had been implemented by it. The method could be achieved not only by B/S mode but also by C/S mode taking advantage of the predominance of the Java language. Some key issues such as locating video data source, playing video, video image acquisition and processing and so on had been expatiated in detail. The operation results of the system show that this method is fully compatible with common video capture device. At the same time the system possesses many excellences as lower cost, more powerful, easier to develop and cross-platform etc. Finally the application prospect of the method which is based on java and JMF is pointed out.

  18. A rapid Look-Locker imaging sequence for quantitative tissue oximetry

    Science.gov (United States)

    Vidya Shankar, Rohini; Kodibagkar, Vikram D.

    2015-03-01

    Tissue oximetry studies using magnetic resonance imaging are increasingly contributing to advances in the imaging and treatment of cancer. The non-invasive measurement of tissue oxygenation (pO2) may facilitate a better understanding of the pathophysiology and prognosis of diseases, particularly in the assessment of the extensive hypoxic regions associated with cancerous lesions. The availability of tumor hypoxia maps could help quantify and predict tumor response to intervention and therapy. The PISTOL (Proton Imaging of Siloxanes to map Tissue Oxygenation Levels) oximetry technique maps the T1 of administered hexamethyldisiloxane (HMDSO), an 1H NMR pO2 reporter molecule in about 3 ½ min. This allows us to subsequently monitor static and dynamic changes in the tissue pO2 (in response to intervention) at various locations due to the linear relationship between 1/T1 and pO2. In this work, an HMDSO-selective Look-Locker imaging sequence with EPI readout has been developed to enable faster PISTOL acquisitions. The new sequence incorporates the fast Look-Locker measurement method to enable T1, and hence, pO2 mapping of HMDSO in under one minute. To demonstrate the application of this pulse sequence in vivo, 50 μL of neat HMDSO was administered to the thigh muscle of a healthy rat (Fischer F344, n=4). Dynamic changes in the mean pO2 of the thigh muscle were measured using both PISTOL and the developed LL oximetry sequence in response to oxygen challenge and compared. Results demonstrate the efficacy of the new sequence in rapidly mapping the pO2 changes, leading to advances in fast quantitative 1H MR oximetry.

  19. Rapid and economical data acquisition in ultrafast frequency-resolved spectroscopy using choppers and a microcontroller.

    Science.gov (United States)

    Guo, Liang; Monahan, Daniele M; Fleming, Graham

    2016-08-08

    Spectrometers and cameras are used in ultrafast spectroscopy to achieve high resolution in both time and frequency domains. Frequency-resolved signals from the camera pixels cannot be processed by common lock-in amplifiers, which have only a limited number of input channels. Here we demonstrate a rapid and economical method that achieves the function of a lock-in amplifier using mechanical choppers and a programmable microcontroller. We demonstrate the method's effectiveness by performing a frequency-resolved pump-probe measurement on the dye Nile Blue in solution.

  20. Simultaneous acquisition of storage phosphor and asymmetric screen-film chest images using a hybrid cassette

    Science.gov (United States)

    Stewart, Brent K.; Kimme-Smith, Carolyn; Johnson, Sandra L.; Johnson, Timothy; Aberle, Denise R.

    1994-05-01

    A hybrid cassette has been developed for simultaneous acquisition of storage phosphor and asymmetric screen-film chest images. This is important for the collection of images for Receiver Operating Characteristic studies comparing conventional radiography and computed radiography, without either increased exposure or non-identical imaging conditions. This hybrid radiographic cassette consists of a computed radiography imaging plate (in front) and an intact, high contrast variant of a commercially available asymmetric screen-film system (in the rear) with a speed of approximately 425. The high contrast, speed and efficiency of this screen-film system allow for positioning of the storage phosphor plate in the front of the cassette. As the imaging plate absorption is approximately 35%, the fast screen-film system provides high quality diagnostic images. There is minimal beam hardening, which is ameliorated by the high contrast of the asymmetric front screen. There is minimal differences in the Plexiglas step wedge phantom gray level values for CR and CR-hybrid images and in optical density values for InSightTM and InSightTM-hybrid films. The signal to noise ratio of either hybrid image, while fractionally less than their standard counterparts, is negligibly so. Only a slight modification in radiographic technique is required (10%) for use of this hybrid cassette, providing images that are virtually the same as those obtained through the standard CR and InSightTM ITC imaging methods.

  1. Seismic imaging of glaciomarine sediments of Antarctica: Optimizing the acquisition parameters

    Digital Repository Service at National Institute of Oceanography (India)

    Pandey, D.; Chaubey, A.K.; Rajan, S.

    of Marine Sciences Vol. 37(4), December 2008, pp. 412-418 Seismic imaging of glaciomarine sediments of Antarctica: Optimizing the acquisition parameters Dhananjai Pandey1*, Anil Chaubey2, S Rajan1 1National Centre for Antarctic and Ocean... discussions on the reflection signature of the glaciomarine sediments of the continental slope and rise off Prydz Bay in east Antarctica in terms of depositional processes. The present study is based on synthetic seismogram modeling using finite...

  2. Knowledge Acquisition, Validation, and Maintenance in a Planning System for Automated Image Processing

    Science.gov (United States)

    Chien, Steve A.

    1996-01-01

    A key obstacle hampering fielding of AI planning applications is the considerable expense of developing, verifying, updating, and maintainting the planning knowledge base (KB). Planning systems must be able to compare favorably in terms of software lifecycle costs to other means of automation such as scripts or rule-based expert systems. This paper describes a planning application of automated imaging processing and our overall approach to knowledge acquisition for this application.

  3. Image acquisition and planimetry systems to develop wounding techniques in 3D wound model

    Directory of Open Access Journals (Sweden)

    Kiefer Ann-Kathrin

    2017-09-01

    Full Text Available Wound healing represents a complex biological repair process. Established 2D monolayers and wounding techniques investigate cell migration, but do not represent coordinated multi-cellular systems. We aim to use wound surface area measurements obtained from image acquisition and planimetry systems to establish our wounding technique and in vitro organotypic tissue. These systems will be used in our future wound healing treatment studies to assess the rate of wound closure in response to wound healing treatment with light therapy (photobiomodulation. The image acquisition and planimetry systems were developed, calibrated, and verified to measure wound surface area in vitro. The system consists of a recording system (Sony DSC HX60, 20.4 M Pixel, 1/2.3″ CMOS sensor and calibrated with 1mm scale paper. Macro photography with an optical zoom magnification of 2:1 achieves sufficient resolution to evaluate the 3mm wound size and healing growth. The camera system was leveled with an aluminum construction to ensure constant distance and orientation of the images. The JPG-format images were processed with a planimetry system in MATLAB. Edge detection enables definition of the wounded area. Wound area can be calculated with surface integrals. To separate the wounded area from the background, the image was filtered in several steps. Agar models, injured through several test persons with different levels of experience, were used as pilot data to test the planimetry software. These image acquisition and planimetry systems support the development of our wound healing research. The reproducibility of our wounding technique can be assessed by the variability in initial wound surface area. Also, wound healing treatment effects can be assessed by the change in rate of wound closure. These techniques represent the foundations of our wound model, wounding technique, and analysis systems in our ongoing studies in wound healing and therapy.

  4. 3D Image Acquisition System Based on Shape from Focus Technique

    Directory of Open Access Journals (Sweden)

    Pierre Gouton

    2013-04-01

    Full Text Available This paper describes the design of a 3D image acquisition system dedicated to natural complex scenes composed of randomly distributed objects with spatial discontinuities. In agronomic sciences, the 3D acquisition of natural scene is difficult due to the complex nature of the scenes. Our system is based on the Shape from Focus technique initially used in the microscopic domain. We propose to adapt this technique to the macroscopic domain and we detail the system as well as the image processing used to perform such technique. The Shape from Focus technique is a monocular and passive 3D acquisition method that resolves the occlusion problem affecting the multi-cameras systems. Indeed, this problem occurs frequently in natural complex scenes like agronomic scenes. The depth information is obtained by acting on optical parameters and mainly the depth of field. A focus measure is applied on a 2D image stack previously acquired by the system. When this focus measure is performed, we can create the depth map of the scene.

  5. EVALUATION OF ACQUISITION STRATEGIES FOR IMAGE-BASED CONSTRUCTION SITE MONITORING

    Directory of Open Access Journals (Sweden)

    S. Tuttas

    2016-06-01

    Full Text Available Construction site monitoring is an essential task for keeping track of the ongoing construction work and providing up-to-date information for a Building Information Model (BIM. The BIM contains the as-planned states (geometry, schedule, costs, ... of a construction project. For updating, the as-built state has to be acquired repeatedly and compared to the as-planned state. In the approach presented here, a 3D representation of the as-built state is calculated from photogrammetric images using multi-view stereo reconstruction. On construction sites one has to cope with several difficulties like security aspects, limited accessibility, occlusions or construction activity. Different acquisition strategies and techniques, namely (i terrestrial acquisition with a hand-held camera, (ii aerial acquisition using a Unmanned Aerial Vehicle (UAV and (iii acquisition using a fixed stereo camera pair at the boom of the crane, are tested on three test sites. They are assessed considering the special needs for the monitoring tasks and limitations on construction sites. The three scenarios are evaluated based on the ability of automation, the required effort for acquisition, the necessary equipment and its maintaining, disturbance of the construction works, and on the accuracy and completeness of the resulting point clouds. Based on the experiences during the test cases the following conclusions can be drawn: Terrestrial acquisition has the lowest requirements on the device setup but lacks on automation and coverage. The crane camera shows the lowest flexibility but the highest grade of automation. The UAV approach can provide the best coverage by combining nadir and oblique views, but can be limited by obstacles and security aspects. The accuracy of the point clouds is evaluated based on plane fitting of selected building parts. The RMS errors of the fitted parts range from 1 to a few cm for the UAV and the hand-held scenario. First results show that the crane

  6. Evaluation of Acquisition Strategies for Image-Based Construction Site Monitoring

    Science.gov (United States)

    Tuttas, S.; Braun, A.; Borrmann, A.; Stilla, U.

    2016-06-01

    Construction site monitoring is an essential task for keeping track of the ongoing construction work and providing up-to-date information for a Building Information Model (BIM). The BIM contains the as-planned states (geometry, schedule, costs, ...) of a construction project. For updating, the as-built state has to be acquired repeatedly and compared to the as-planned state. In the approach presented here, a 3D representation of the as-built state is calculated from photogrammetric images using multi-view stereo reconstruction. On construction sites one has to cope with several difficulties like security aspects, limited accessibility, occlusions or construction activity. Different acquisition strategies and techniques, namely (i) terrestrial acquisition with a hand-held camera, (ii) aerial acquisition using a Unmanned Aerial Vehicle (UAV) and (iii) acquisition using a fixed stereo camera pair at the boom of the crane, are tested on three test sites. They are assessed considering the special needs for the monitoring tasks and limitations on construction sites. The three scenarios are evaluated based on the ability of automation, the required effort for acquisition, the necessary equipment and its maintaining, disturbance of the construction works, and on the accuracy and completeness of the resulting point clouds. Based on the experiences during the test cases the following conclusions can be drawn: Terrestrial acquisition has the lowest requirements on the device setup but lacks on automation and coverage. The crane camera shows the lowest flexibility but the highest grade of automation. The UAV approach can provide the best coverage by combining nadir and oblique views, but can be limited by obstacles and security aspects. The accuracy of the point clouds is evaluated based on plane fitting of selected building parts. The RMS errors of the fitted parts range from 1 to a few cm for the UAV and the hand-held scenario. First results show that the crane camera

  7. Image acquisition device of inspection robot based on adaptive rotation regulation of polarizer

    Science.gov (United States)

    Dong, Maoqi; Wang, Xingguang; Liang, Tao; Yang, Guoqing; Zhang, Chuangyou; Gao, Faqin

    2017-12-01

    An image processing device of inspection robot with adaptive polarization adjustment is proposed, that the device includes the inspection robot body, the image collecting mechanism, the polarizer and the polarizer automatic actuating device. Where, the image acquisition mechanism is arranged at the front of the inspection robot body for collecting equipment image data in the substation. Polarizer is fixed on the automatic actuating device of polarizer, and installed in front of the image acquisition mechanism, and that the optical axis of the camera vertically goes through the polarizer and the polarizer rotates with the optical axis of the visible camera as the central axis. The simulation results show that the system solves the fuzzy problems of the equipment that are caused by glare, reflection of light and shadow, and the robot can observe details of the running status of electrical equipment. And the full coverage of the substation equipment inspection robot observation target is achieved, which ensures the safe operation of the substation equipment.

  8. Dopamine transporter imaging in rapid eye movement sleep behavior disorder

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yu Kyeong; Yoon, In Young; Kim, Jong Min; Jeong, Seok Hoon; Kim, Ji Sun; Lee, Byung Chul; Lee, Won Woo; Kim, Sang Eun [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    The pathogenesis of rapid eye movement (REM) sleep behavior disorder (RBD) is still unknown. However, involvement of dopaminergic system in RBD has been hypothesized because of frequent association with degenerative movement disorders such as Parkinson's disease. The purpose of this study was to examine the extent and pattern of loss of dopamine transporter in RBD using FP-CIT SPECT. Fourteen patient with idiopathic RBD (mean age:665 yrs, M:F=10:3) participated in this study. Polysonmography confirmed loss of REM atonia and determined RBD severities by amount of tonic/phasic muscle activity during REM sleep in all cases. To compare with RBD, 14 early idiopathic Parkinson's disease rated as Hoehn and Yahr stage 1 (IPD) and 12 healthy controls were also selected. All participants performed single-photon emission computed tomography (SPECT) imaging 3 hours after injection of [123I]FP-CIT. Regions of interest were drawn on bilateral caudate and putamen, whole striatum and occipital cortex. Specific binding for dopamine transporters (DAT) were calculated using region to occipital uptake ratio based on the transient equilibrium method. Overall mean of DAT density in the striatum was lower in RBD group than controls, and higher than IPD group, However, DAT density in most individual RBD was still within normal range, and total striatal DAT density was not correlated with severity of RBD. Meanwhile, the caudate to putamen uptake ratio (C/P ratio) in RBD group was insignificantly higher than those in healthy controls. Nevertheless, C/P ratio within RBD group was reversely correlated with the RBD severity. Our study suggested that nigrostriatal dopaminergic degeneration could be a part of the pathogenesis of RBD, but not essential for the development of RBD. Further longitudinal evaluation of presynaptic dopaminergic system in idiopathic RBD may guarantee the more understanding for RBD and associated neurodegenerative disease.

  9. High-Performance Image Acquisition and Processing System with MTCA.4

    Science.gov (United States)

    Makowski, D.; Mielczarek, A.; Perek, P.; Jabłoński, G.; Orlikowski, M.; Sakowicz, B.; Napieralski, A.; Makijarvi, P.; Simrock, S.; Martin, V.

    2015-06-01

    Fast evolution of high-performance cameras in recent years has made them promising tools for observing transient and fast events in large-scale scientific experiments. Complex experiments, such as ITER, take advantage of high-performance imaging system consisting of several fast cameras working in the range of visible and infrared light. However, the application of such devices requires a usage of high-performance data acquisition systems able to read and transfer large amount of data, reaching even 10 Gbit/s for a single camera. The MTCA.4 form factor fulfils the requirements of demanding imaging systems. The paper presents a first implementation of a complete image acquisition system built on the basis of MTCA.4 architecture, which is dedicated for the operation with high-resolution fast cameras equipped with Camera Link interface. Image data from the camera are received by the frame grabber card and transmitted to the host via the PCIe interface. The modular structure of MTCA.4 architecture allows connecting several cameras to a single MTCA chassis. The system can operate in two modes: with internal CPU installed in the MTCA chassis or with external CPU connected to the chassis with PCIe link. The usage of the external CPU opens a possibility to aggregate data from different subsystems. The system supports precise synchronization with the time reference using Precise Timing Protocol (IEEE 1588). The timing modules ensure clock distribution and triggers generation on backplane lines. These allow synchronization of image acquisition from different cameras with high precision. The software support for the system includes low-level drivers and API libraries for all components and a high-level EPICS-based environment for system control and monitoring.

  10. Incorporation of prior knowledge in compressed sensing for faster acquisition of hyperpolarized gas images.

    Science.gov (United States)

    Ajraoui, S; Parra-Robles, J; Wild, J M

    2013-02-01

    Adding prior knowledge to compressed sensing reconstruction can improve image reconstruction. In this work, two approaches are investigated to improve reconstruction of two-dimensional hyperpolarized (3)He lung ventilation images using prior knowledge. When compared against a standard compressed sensing reconstruction, the proposed methods allowed acquisition of images with higher under-sampling factors and reduction of the blurring effects that increase with higher reduction factors when fixed flip angles are used. These methods incorporate the prior knowledge of polarization decay of hyperpolarized (3)He and the mutual anatomical information from a registered (1)H image acquired in the same breath. Three times accelerated two-dimensional images reconstructed with compressed sensing and prior knowledge gave lower root-mean square error, than images reconstructed without introduction of any prior information. When introducing the polarization decay as prior knowledge, a significant improvement was achieved in the lung region, the root mean square value decreased by 45% and from the whole image by 36%. When introducing the mutual anatomical information as prior knowledge, the root mean square decreased by 21% over the lung region and by 15% over the whole image. Copyright © 2012 Wiley Periodicals, Inc.

  11. Effects of a patient's name and image on medical knowledge acquisition.

    Science.gov (United States)

    Guajardo, Jesus R; Petershack, Jean A; Caplow, Julie A; Littlefield, John H

    2015-01-01

    To assess whether there are differences in medical students' (MS) knowledge acquisition after being provided a virtual patient (VP) case summary with a patient's name and facial picture included compared to no patient's name or image. 76 MS from four clerkship blocks participated. Blocks one and three (Treatment group) were provided case materials containing the patient's name and facial picture while blocks two and four (Control group) were provided similar materials without the patient's name or image. Knowledge acquisition was evaluated with a multiple-choice-question examination (CQA_K). Treatment group CQA_K scores were 64.6% (block one, n = 18) and 76.0% (block three, n = 22). Control group scores were 71.7%, (block two, n = 17) and 68.4% (block four, n = 19). ANOVA F-test among the four block mean scores was not significant; F (3, 72) = 1.68, p = 0.18, η2=0.07. Only 22.2% and 27.3% of the MS from blocks one and three respectively correctly recalled the patient's name while 16.7% and 40.9% recalled the correct final diagnosis of the patient. These results suggest that including a patient's name and facial picture on reading materials may not improve MS knowledge acquisition. Corroborating studies should be performed before applying these results to the design of instructional materials.

  12. Implementation of rapid imaging system on the COMPASS tokamak.

    Czech Academy of Sciences Publication Activity Database

    Havránek, Aleš; Weinzettl, Vladimír; Fridrich, David; Cavalier, Jordan; Urban, Jakub; Komm, Michael

    2017-01-01

    Roč. 123, November (2017), s. 857-860 ISSN 0920-3796. [SOFT 2016: Symposium on Fusion Technology /29./. Prague, 05.09.2016-09.09.2016] R&D Projects: GA MŠk(CZ) LM2015045 Institutional support: RVO:61389021 Keywords : Camera * Data acquisition * Video processing * Tokamak Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.319, year: 2016 http://www.sciencedirect.com/science/article/pii/S092037961730354X

  13. Dynamic whole-body PET parametric imaging: I. Concept, acquisition protocol optimization and clinical application.

    Science.gov (United States)

    Karakatsanis, Nicolas A; Lodge, Martin A; Tahari, Abdel K; Zhou, Y; Wahl, Richard L; Rahmim, Arman

    2013-10-21

    Static whole-body PET/CT, employing the standardized uptake value (SUV), is considered the standard clinical approach to diagnosis and treatment response monitoring for a wide range of oncologic malignancies. Alternative PET protocols involving dynamic acquisition of temporal images have been implemented in the research setting, allowing quantification of tracer dynamics, an important capability for tumor characterization and treatment response monitoring. Nonetheless, dynamic protocols have been confined to single-bed-coverage limiting the axial field-of-view to ~15-20 cm, and have not been translated to the routine clinical context of whole-body PET imaging for the inspection of disseminated disease. Here, we pursue a transition to dynamic whole-body PET parametric imaging, by presenting, within a unified framework, clinically feasible multi-bed dynamic PET acquisition protocols and parametric imaging methods. We investigate solutions to address the challenges of: (i) long acquisitions, (ii) small number of dynamic frames per bed, and (iii) non-invasive quantification of kinetics in the plasma. In the present study, a novel dynamic (4D) whole-body PET acquisition protocol of ~45 min total length is presented, composed of (i) an initial 6 min dynamic PET scan (24 frames) over the heart, followed by (ii) a sequence of multi-pass multi-bed PET scans (six passes × seven bed positions, each scanned for 45 s). Standard Patlak linear graphical analysis modeling was employed, coupled with image-derived plasma input function measurements. Ordinary least squares Patlak estimation was used as the baseline regression method to quantify the physiological parameters of tracer uptake rate Ki and total blood distribution volume V on an individual voxel basis. Extensive Monte Carlo simulation studies, using a wide set of published kinetic FDG parameters and GATE and XCAT platforms, were conducted to optimize the acquisition protocol from a range of ten different clinically

  14. Dynamic whole body PET parametric imaging: I. Concept, acquisition protocol optimization and clinical application

    Science.gov (United States)

    Karakatsanis, Nicolas A.; Lodge, Martin A.; Tahari, Abdel K.; Zhou, Y.; Wahl, Richard L.; Rahmim, Arman

    2013-01-01

    Static whole body PET/CT, employing the standardized uptake value (SUV), is considered the standard clinical approach to diagnosis and treatment response monitoring for a wide range of oncologic malignancies. Alternative PET protocols involving dynamic acquisition of temporal images have been implemented in the research setting, allowing quantification of tracer dynamics, an important capability for tumor characterization and treatment response monitoring. Nonetheless, dynamic protocols have been confined to single bed-coverage limiting the axial field-of-view to ~15–20 cm, and have not been translated to the routine clinical context of whole-body PET imaging for the inspection of disseminated disease. Here, we pursue a transition to dynamic whole body PET parametric imaging, by presenting, within a unified framework, clinically feasible multi-bed dynamic PET acquisition protocols and parametric imaging methods. We investigate solutions to address the challenges of: (i) long acquisitions, (ii) small number of dynamic frames per bed, and (iii) non-invasive quantification of kinetics in the plasma. In the present study, a novel dynamic (4D) whole body PET acquisition protocol of ~45min total length is presented, composed of (i) an initial 6-min dynamic PET scan (24 frames) over the heart, followed by (ii) a sequence of multi-pass multi-bed PET scans (6 passes x 7 bed positions, each scanned for 45sec). Standard Patlak linear graphical analysis modeling was employed, coupled with image-derived plasma input function measurements. Ordinary least squares (OLS) Patlak estimation was used as the baseline regression method to quantify the physiological parameters of tracer uptake rate Ki and total blood distribution volume V on an individual voxel basis. Extensive Monte Carlo simulation studies, using a wide set of published kinetic FDG parameters and GATE and XCAT platforms, were conducted to optimize the acquisition protocol from a range of 10 different clinically

  15. Single-heartbeat electromechanical wave imaging with optimal strain estimation using temporally unequispaced acquisition sequences.

    Science.gov (United States)

    Provost, Jean; Thiébaut, Stéphane; Luo, Jianwen; Konofagou, Elisa E

    2012-02-21

    Electromechanical Wave Imaging (EWI) is a non-invasive, ultrasound-based imaging method capable of mapping the electromechanical wave (EW) in vivo, i.e. the transient deformations occurring in response to the electrical activation of the heart. Optimal imaging frame rates, in terms of the elastographic signal-to-noise ratio, to capture the EW cannot be achieved due to the limitations of conventional imaging sequences, in which the frame rate is low and tied to the imaging parameters. To achieve higher frame rates, EWI is typically performed by combining sectors acquired during separate heartbeats, which are then combined into a single view. However, the frame rates achieved remain potentially sub-optimal and this approach precludes the study of non-periodic arrhythmias. This paper describes a temporally unequispaced acquisition sequence (TUAS) for which a wide range of frame rates are achievable independently of the imaging parameters, while maintaining a full view of the heart at high beam density. TUAS is first used to determine the optimal frame rate for EWI in a paced canine heart in vivo and then to image during ventricular fibrillation. These results indicate how EWI can be optimally performed within a single heartbeat, during free breathing and in real time, for both periodic and non-periodic cardiac events.

  16. Task-based data-acquisition optimization for sparse image reconstruction systems

    Science.gov (United States)

    Chen, Yujia; Lou, Yang; Kupinski, Matthew A.; Anastasio, Mark A.

    2017-03-01

    Conventional wisdom dictates that imaging hardware should be optimized by use of an ideal observer (IO) that exploits full statistical knowledge of the class of objects to be imaged, without consideration of the reconstruction method to be employed. However, accurate and tractable models of the complete object statistics are often difficult to determine in practice. Moreover, in imaging systems that employ compressive sensing concepts, imaging hardware and (sparse) image reconstruction are innately coupled technologies. We have previously proposed a sparsity-driven ideal observer (SDIO) that can be employed to optimize hardware by use of a stochastic object model that describes object sparsity. The SDIO and sparse reconstruction method can therefore be "matched" in the sense that they both utilize the same statistical information regarding the class of objects to be imaged. To efficiently compute SDIO performance, the posterior distribution is estimated by use of computational tools developed recently for variational Bayesian inference. Subsequently, the SDIO test statistic can be computed semi-analytically. The advantages of employing the SDIO instead of a Hotelling observer are systematically demonstrated in case studies in which magnetic resonance imaging (MRI) data acquisition schemes are optimized for signal detection tasks.

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

    DEFF Research Database (Denmark)

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

    2010-01-01

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

  18. 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.

  19. MO-DE-BRA-06: 3D Image Acquisition and Reconstruction Explained with Online Animations

    Energy Technology Data Exchange (ETDEWEB)

    Kesner, A

    2016-06-15

    Purpose: Understanding the principles of 3D imaging and image reconstruction is fundamental to the field of medical imaging. Clinicians, technologists, physicists, patients, students, and inquisitive minds all stand to benefit from greater comprehension of the supporting technologies. To help explain the basic principles of 3D imaging, we developed multi-frame animations that convey the concepts of tomographic imaging. The series of free (gif) animations are accessible online, and provide a multimedia introduction to the main concepts of image reconstruction. Methods: Text and animations were created to convey the principles of analytic tomography in CT, PET, and SPECT. Specific topics covered included: principles of sinograms/image data storage, forward projection, principles of PET acquisitions, and filtered backprojection. A total of 8 animations were created and presented for CT, PET, and digital phantom formats. In addition, a free executable is also provided to allow users to create their own tomographic animations – providing an opportunity for interaction and personalization to help foster user interest. Results: Tutorial text and animations have been posted online, freely available to view or download. The animations are in first position in a google search of “image reconstruction animations”. The website currently receives approximately 200 hits/month, from all over the world, and the usage is growing. Positive feedback has been collected from users. Conclusion: We identified a need for improved teaching tools to help visualize the (temporally variant) concepts of image reconstruction, and have shown that animations can be a useful tool for this aspect of education. Furthermore, posting animations freely on the web has shown to be a good way to maximize their impact in the community. In future endeavors, we hope to expand this animated content, to cover principles of iterative reconstruction, as well as other phenomena relating to imaging.

  20. [Rapid total body fat measurement by magnetic resonance imaging: quantification and topography].

    Science.gov (United States)

    Vogt, F M; Ruehm, S; Hunold, P; de Greiff, A; Nuefer, M; Barkhausen, J; Ladd, S C

    2007-05-01

    To evaluate a rapid and comprehensive MR protocol based on a T1-weighted sequence in conjunction with a rolling table platform for the quantification of total body fat. 11 healthy volunteers and 50 patients were included in the study. MR data was acquired on a 1.5-T system (Siemens Magnetom Sonata). An axial T1-weighted flash 2D sequence (TR 101, TE 4.7, FA 70, FOV 50 cm, 205 x 256 matrix, slice thickness: 10 mm, 10 mm interslice gap) was used for data acquisition. Patients were placed in a supine position on a rolling table platform capable of acquiring multiple consecutive data sets by pulling the patient through the isocenter of the magnet. Data sets extending from the upper to lower extremities were collected. The images were analyzed with respect to the amount of intraabdominal, subcutaneous and total abdominal fat by semi-automated image segmentation software that employs a contour-following algorithm. The obtained MR images were able to be evaluated for all volunteers and patients. Excellent correlation was found between whole body MRI results in volunteers with DEXA (r (2) = 0.95) and bioimpedance (r (2) = 0.89) measurements, while the correlation coefficient was 0.66 between MRI and BMI, indicating only moderate reliability of the BMI method. Variations in patients with respect to the amount of total, subcutaneous, and intraabdominal adipose tissue was not related to standard anthropometric measurements and metabolic lipid profiles (r (2) = 0,001 to 0.48). The results showed that there was a significant variation in intraabdominal adipose tissue which could not be predicted from the total body fat (r (2) = 0.14) or subcutaneous adipose tissue (r (2) = 0.04). Although no significant differences in BMI could be found between females and males (p = 0.26), females showed significantly higher total and subcutaneous abdominal adipose tissue (p < 0.05). This MR protocol can be used for the rapid and non-invasive quantification of body fat. The missing

  1. Advanced camera image data acquisition system for Pi-of-the-Sky

    Science.gov (United States)

    Kwiatkowski, Maciej; Kasprowicz, Grzegorz; Pozniak, Krzysztof; Romaniuk, Ryszard; Wrochna, Grzegorz

    2008-11-01

    The paper describes a new generation of high performance, remote control, CCD cameras designed for astronomical applications. A completely new camera PCB was designed, manufactured, tested and commissioned. The CCD chip was positioned in a different way than previously resulting in better performance of the astronomical video data acquisition system. The camera was built using a low-noise, 4Mpixel CCD circuit by STA. The electronic circuit of the camera is highly parameterized and reconfigurable, as well as modular in comparison with the solution of first generation, due to application of open software solutions and FPGA circuit, Altera Cyclone EP1C6. New algorithms were implemented into the FPGA chip. There were used the following advanced electronic circuit in the camera system: microcontroller CY7C68013a (core 8051) by Cypress, image processor AD9826 by Analog Devices, GigEth interface RTL8169s by Realtec, memory SDRAM AT45DB642 by Atmel, CPU typr microprocessor ARM926EJ-S AT91SAM9260 by ARM and Atmel. Software solutions for the camera and its remote control, as well as image data acquisition are based only on the open source platform. There were used the following image interfaces ISI and API V4L2, data bus AMBA, AHB, INDI protocol. The camera will be replicated in 20 pieces and is designed for continuous on-line, wide angle observations of the sky in the research program Pi-of-the-Sky.

  2. Data acquisition and control system for the ECE imaging diagnostic on the EAST tokamak

    Science.gov (United States)

    Luo, C.; Lan, T.; Zhu, Y.; Xie, J.; Gao, B.; Liu, W.; Yu, C.; Milne, P. G.; Domier, C. W.; Luhmann, N. C.

    2017-06-01

    A 384-channel electron cyclotron emission imaging (ECEI) system is installed on the experimental advanced superconducting tokamak (EAST) and 7-gigabyte data is produced for each regular discharge of a 10-second pulse. The data acquisition and control (DAC) system for the EAST ECEI diagnostics covers the large data production and embeds the ability to report the data quality instantly after the discharge. The symmetric routing design of the timing signal distributions among the 384 channels provides a low-cost solution to the synchronization of a large number of channels. The application of the load-balance bond service largely reduces the configuration difficulty and the cost in the high-speed data transferring tasks. Benefiting from the various kinds of hardware units with dedicated functionalities, an automated and user interactive DAC work flow is achieved, including the pre-selections of the automation scheme and the observation region, 384-channel data acquisition and local caching, post-discharge imaging data quality evaluation, remote system status monitoring, and inter-discharge imaging system event handling. The system configuration in a specific physics experiment is further optimized through the associated operating software which is enhanced by the input of the tokamak operation status and the region of interest (ROI) from other diagnostics. The DAC system is based on a modularized design and scalable to the long-pulse discharges in the EAST tokamak.

  3. Cellular Phone-Based Image Acquisition and Quantitative Ratiometric Method for Detecting Cocaine and Benzoylecgonine for Biological and Forensic Applications

    Directory of Open Access Journals (Sweden)

    Brian A. Cadle

    2010-01-01

    Full Text Available Here we describe the first report of using low-cost cellular or web-based digital cameras to image and quantify standardized rapid immunoassay strips as a new point-of-care diagnostic and forensics tool with health applications. Quantitative ratiometric pixel density analysis (QRPDA is an automated method requiring end-users to utilize inexpensive (~ $1 USD/each immunotest strips, a commonly available web or mobile phone camera or scanner, and internet or cellular service. A model is described whereby a central computer server and freely available IMAGEJ image analysis software records and analyzes the incoming image data with time-stamp and geo-tag information and performs the QRPDA using custom JAVA based macros ( http://www.neurocloud.org . To demonstrate QRPDA we developed a standardized method using rapid immunotest strips directed against cocaine and its major metabolite, benzoylecgonine. Images from standardized samples were acquired using several devices, including a mobile phone camera, web cam, and scanner. We performed image analysis of three brands of commercially available dye-conjugated anti-cocaine/benzoylecgonine (COC/BE antibody test strips in response to three different series of cocaine concentrations ranging from 0.1 to 300 ng/ml and BE concentrations ranging from 0.003 to 0.1 ng/ml. This data was then used to create standard curves to allow quantification of COC/BE in biological samples. Across all devices, QRPDA quantification of COC and BE proved to be a sensitive, economical, and faster alternative to more costly methods, such as gas chromatography-mass spectrometry, tandem mass spectrometry, or high pressure liquid chromatography. The limit of detection was determined to be between 0.1 and 5 ng/ml. To simulate conditions in the field, QRPDA was found to be robust under a variety of image acquisition and testing conditions that varied temperature, lighting, resolution, magnification and concentrations of biological fluid

  4. Cellular phone-based image acquisition and quantitative ratiometric method for detecting cocaine and benzoylecgonine for biological and forensic applications.

    Science.gov (United States)

    Cadle, Brian A; Rasmus, Kristin C; Varela, Juan A; Leverich, Leah S; O'Neill, Casey E; Bachtell, Ryan K; Cooper, Donald C

    2010-01-01

    Here we describe the first report of using low-cost cellular or web-based digital cameras to image and quantify standardized rapid immunoassay strips as a new point-of-care diagnostic and forensics tool with health applications. Quantitative ratiometric pixel density analysis (QRPDA) is an automated method requiring end-users to utilize inexpensive (∼ $1 USD/each) immunotest strips, a commonly available web or mobile phone camera or scanner, and internet or cellular service. A model is described whereby a central computer server and freely available IMAGEJ image analysis software records and analyzes the incoming image data with time-stamp and geo-tag information and performs the QRPDA using custom JAVA based macros (http://www.neurocloud.org). To demonstrate QRPDA we developed a standardized method using rapid immunotest strips directed against cocaine and its major metabolite, benzoylecgonine. Images from standardized samples were acquired using several devices, including a mobile phone camera, web cam, and scanner. We performed image analysis of three brands of commercially available dye-conjugated anti-cocaine/benzoylecgonine (COC/BE) antibody test strips in response to three different series of cocaine concentrations ranging from 0.1 to 300 ng/ml and BE concentrations ranging from 0.003 to 0.1 ng/ml. This data was then used to create standard curves to allow quantification of COC/BE in biological samples. Across all devices, QRPDA quantification of COC and BE proved to be a sensitive, economical, and faster alternative to more costly methods, such as gas chromatography-mass spectrometry, tandem mass spectrometry, or high pressure liquid chromatography. The limit of detection was determined to be between 0.1 and 5 ng/ml. To simulate conditions in the field, QRPDA was found to be robust under a variety of image acquisition and testing conditions that varied temperature, lighting, resolution, magnification and concentrations of biological fluid in a sample. To

  5. Wide-field flexible endoscope for simultaneous color and NIR fluorescence image acquisition during surveillance colonoscopy

    Science.gov (United States)

    García-Allende, P. Beatriz; Nagengast, Wouter B.; Glatz, Jürgen; Ntziachristos, Vasilis

    2013-03-01

    Colorectal cancer (CRC) is the third most common form of cancer and, despite recent declines in both incidence and mortality, it still remains the second leading cause of cancer-related deaths in the western world. Colonoscopy is the standard for detection and removal of premalignant lesions to prevent CRC. The major challenges that physicians face during surveillance colonoscopy are the high adenoma miss-rates and the lack of functional information to facilitate decision-making concerning which lesions to remove. Targeted imaging with NIR fluorescence would address these limitations. Tissue penetration is increased in the NIR range while the combination with targeted NIR fluorescent agents provides molecularly specific detection of cancer cells, i.e. a red-flag detection strategy that allows tumor imaging with optimal sensitivity and specificity. The development of a flexible endoscopic fluorescence imaging method that can be integrated with standard medical endoscopes and facilitates the clinical use of this potential is described in this work. A semi-disposable coherent fiber optic imaging bundle that is traditionally employed in the exploration of biliary and pancreatic ducts is proposed, since it is long and thin enough to be guided through the working channel of a traditional video colonoscope allowing visualization of proximal lesions in the colon. A custom developed zoom system magnifies the image of the proximal end of the imaging bundle to fill the dimensions of two cameras operating in parallel providing the simultaneous color and fluorescence video acquisition.

  6. Target recognition and phase acquisition by using incoherent digital holographic imaging

    Science.gov (United States)

    Lee, Munseob; Lee, Byung-Tak

    2017-05-01

    In this study, we proposed the Incoherent Digital Holographic Imaging (IDHI) for recognition and phase information of dedicated target. Although recent development of a number of target recognition techniques such as LIDAR, there have limited success in target discrimination, in part due to low-resolution, low scanning speed, and computation power. In the paper, the proposed system consists of the incoherent light source, such as LED, Michelson interferometer, and digital CCD for acquisition of four phase shifting image. First of all, to compare with relative coherence, we used a source as laser and LED, respectively. Through numerical reconstruction by using the four phase shifting method and Fresnel diffraction method, we recovered the intensity and phase image of USAF resolution target apart from about 1.0m distance. In this experiment, we show 1.2 times improvement in resolution compared to conventional imaging. Finally, to confirm the recognition result of camouflaged targets with the same color from background, we carry out to test holographic imaging in incoherent light. In this result, we showed the possibility of a target detection and recognition that used three dimensional shape and size signatures, numerical distance from phase information of obtained holographic image.

  7. Matlab-based interface for the simultaneous acquisition of force measures and Doppler ultrasound muscular images.

    Science.gov (United States)

    Ferrer-Buedo, José; Martínez-Sober, Marcelino; Alakhdar-Mohmara, Yasser; Soria-Olivas, Emilio; Benítez-Martínez, Josep C; Martínez-Martínez, José M

    2013-04-01

    This paper tackles the design of a graphical user interface (GUI) based on Matlab (MathWorks Inc., MA), a worldwide standard in the processing of biosignals, which allows the acquisition of muscular force signals and images from a ultrasound scanner simultaneously. Thus, it is possible to unify two key magnitudes for analyzing the evolution of muscular injuries: the force exerted by the muscle and section/length of the muscle when such force is exerted. This paper describes the modules developed to finally show its applicability with a case study to analyze the functioning capacity of the shoulder rotator cuff. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  8. Acquisition time reduction in magnetic resonance spectroscopic imaging using discrete wavelet encoding.

    Science.gov (United States)

    Serrai, Hacene; Senhadji, Lotfi

    2005-11-01

    This paper describes a new magnetic resonance spectroscopic imaging (MRSI) technique based upon the discrete wavelet transform to reduce acquisition time and cross voxel contamination. Prototype functions called wavelets are used in wavelet encoding to localize defined regions in localized space by dilations and translations. Wavelet encoding in MRSI is achieved by matching the slice selective RF pulse profiles to a set of dilated and translated wavelets. Single and dual band slice selective excitation and refocusing pulses, with profiles resembling Haar wavelets, are used in a spin-echo sequence to acquire 2D-MRSI wavelet encoding data. The 2D space region is spanned up to the desired resolution by a proportional number of dilations (increases in the localization gradients) and translations (frequency shift) of the Haar wavelets (RF pulses). Acquisition time is reduced by acquiring successive MR signals from regions of space with variable size and different locations with no requirement for a TR waiting time between acquisitions. An inverse wavelet transform is performed on the data to produce the correct spatial MR signal distribution.

  9. Intraoperative Molecular Imaging for Rapid Assessment of Tumor Margins

    Science.gov (United States)

    2011-09-01

    approach in animal models using a the MRI- FMT imaging system (Task 5). A description of the primary accomplishments and ongoing efforts follows...guided fluorescence molecular tomography ( FMT ) of ( ) ( ) ( ) tBP k NTNTT etCBP kRktCRtC + − ∗    + ++= 12121 2 1 9 two fluorescent probes in...administration, mice were imaged for an hour at approximately two minutes per frame using an MR-coupled FMT system. The imaging system is a spectrometer

  10. Image acquisition optimization of a limited-angle intrafraction verification (LIVE) system for lung radiotherapy.

    Science.gov (United States)

    Zhang, Yawei; Deng, Xinchen; Yin, Fang-Fang; Ren, Lei

    2017-11-01

    Limited-angle intrafraction verification (LIVE) has been previously developed for four-dimensional (4D) intrafraction target verification either during arc delivery or between three-dimensional (3D)/IMRT beams. Preliminary studies showed that LIVE can accurately estimate the target volume using kV/MV projections acquired over orthogonal view 30° scan angles. Currently, the LIVE imaging acquisition requires slow gantry rotation and is not clinically optimized. The goal of this study is to optimize the image acquisition parameters of LIVE for different patient respiratory periods and gantry rotation speeds for the effective clinical implementation of the system. Limited-angle intrafraction verification imaging acquisition was optimized using a digital anthropomorphic phantom (XCAT) with simulated respiratory periods varying from 3 s to 6 s and gantry rotation speeds varying from 1°/s to 6°/s. LIVE scanning time was optimized by minimizing the number of respiratory cycles needed for the four-dimensional scan, and imaging dose was optimized by minimizing the number of kV and MV projections needed for four-dimensional estimation. The estimation accuracy was evaluated by calculating both the center-of-mass-shift (COMS) and three-dimensional volume-percentage-difference (VPD) between the tumor in estimated images and the ground truth images. The robustness of LIVE was evaluated with varied respiratory patterns, tumor sizes, and tumor locations in XCAT simulation. A dynamic thoracic phantom (CIRS) was used to further validate the optimized imaging schemes from XCAT study with changes of respiratory patterns, tumor sizes, and imaging scanning directions. Respiratory periods, gantry rotation speeds, number of respiratory cycles scanned and number of kV/MV projections acquired were all positively correlated with the estimation accuracy of LIVE. Faster gantry rotation speed or longer respiratory period allowed less respiratory cycles to be scanned and less kV/MV projections

  11. Implementing an Accurate and Rapid Sparse Sampling Approach for Low-Dose Atomic Resolution STEM Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kovarik, Libor; Stevens, Andrew J.; Liyu, Andrey V.; Browning, Nigel D.

    2016-10-17

    Aberration correction for scanning transmission electron microscopes (STEM) has dramatically increased spatial image resolution for beam-stable materials, but it is the sample stability rather than the microscope that often limits the practical resolution of STEM images. To extract physical information from images of beam sensitive materials it is becoming clear that there is a critical dose/dose-rate below which the images can be interpreted as representative of the pristine material, while above it the observation is dominated by beam effects. Here we describe an experimental approach for sparse sampling in the STEM and in-painting image reconstruction in order to reduce the electron dose/dose-rate to the sample during imaging. By characterizing the induction limited rise-time and hysteresis in scan coils, we show that sparse line-hopping approach to scan randomization can be implemented that optimizes both the speed of the scan and the amount of the sample that needs to be illuminated by the beam. The dose and acquisition time for the sparse sampling is shown to be effectively decreased by factor of 5x relative to conventional acquisition, permitting imaging of beam sensitive materials to be obtained without changing the microscope operating parameters. The use of sparse line-hopping scan to acquire STEM images is demonstrated with atomic resolution aberration corrected Z-contrast images of CaCO3, a material that is traditionally difficult to image by TEM/STEM because of dose issues.

  12. The rapid imaging renaissance: sparser samples, denser dimensions, and glimmerings of a grand unified tomography

    Science.gov (United States)

    Sodickson, Daniel K.; Feng, Li; Knoll, Florian; Cloos, Martijn; Ben-Eliezer, Noam; Axel, Leon; Chandarana, Hersh; Block, Tobias; Otazo, Ricardo

    2015-03-01

    The task of imaging is to gather spatiotemporal information which can be organized into a coherent map. Tomographic imaging in particular involves the use of multiple projections, or other interactions of a probe (light, sound, etc.) with a body, in order to determine cross-sectional information. Though the probes and the corresponding imaging modalities may vary, and though the methodology of particular imaging approaches is in constant ferment, the conceptual underpinnings of tomographic imaging have in many ways remained fixed for many decades. Recent advances in applied mathematics, however, have begun to roil this intellectual landscape. The advent of compressed sensing, anticipated in various algorithms dating back many years but unleashed in full theoretical force in the last decade, has changed the way imagers have begun to think about data acquisition and image reconstruction. The power of incoherent sampling and sparsity-enforcing reconstruction has been demonstrated in various contexts and, when combined with other modern fast imaging techniques, has enabled unprecedented increases in imaging efficiency. Perhaps more importantly, however, such approaches have spurred a shift in perspective, prompting us to focus less on nominal data sufficiency than on information content. Beginning with examples from MRI, then proceeding through selected other modalities such as CT and PET, as well as multimodality combinations, this paper explores the potential of newly evolving acquisition and reconstruction paradigms to change the way we do imaging in the lab and in the clinic.

  13. Single-Heartbeat Electromechanical Wave Imaging with Optimal Strain Estimation Using Temporally-Unequispaced Acquisition Sequences

    Science.gov (United States)

    Provost, Jean; Thiébaut, Stéphane; Luo, Jianwen; Konofagou, Elisa E.

    2014-01-01

    Electromechanical Wave Imaging (EWI) is a non-invasive, ultrasound-based imaging method capable of mapping the electromechanical wave (EW) in vivo, i.e., the transient deformations occurring in response to the electrical activation of the heart. Achieving the optimal imaging frame rates, in terms of the elastographic signal-to-noise ratio, to capture the EW in a full-view of the heart poses a technical challenge due to the limitations of conventional imaging sequences, in which the frame rate is low and tied to the imaging parameters. To achieve higher frame rates, EWI is typically performed in multiple small regions of interest acquired over separate heartbeats, which are then combined into a single view. However, the reliance on multiple heartbeats has previously precluded the method from its application in non-periodic arrhythmias such as fibrillation. Moreover, the frame rates achieved remain sub-optimal, because they are determined by the imaging parameters rather than being optimized to image the EW. In this paper, we develop a temporally-unequispaced acquisition sequence (TUAS) for which a wide range of frame rates are achievable independently of the imaging parameters, while maintaining a full view of the heart at high beam density. TUAS is first used to determine the optimal frame rate for EWI in a paced canine heart in vivo. The feasibility of performing single-heartbeat EWI during ventricular fibrillation is then demonstrated. These results indicate that EWI can be performed optimally, within a single heartbeat, during free breathing, and implemented in real time for periodic and non-periodic cardiac events. PMID:22297208

  14. [Acquisition and storage methods for image data collected in Chinese medicine resources survey].

    Science.gov (United States)

    Li, Li; Wei, Sheng-Li; Wang, Wen-Quan; Guo, Zheng-Zheng; Li, Yong-Jie; Zhang, Xiao-Qin

    2014-04-01

    The acquisition and storage of the image data are important in the Chinese medicine resources survey, and it is important data and evidence for the process and the results. The image data of the Chinese medicinal materials' habitat, original plant or animal, processing in habitat, commodity form, the relative contents and workshop scenarios in the investigation are important for the compiling of the Color Atlas of National Chinese Medicine Resources, mapping the digital scattergram of the Chinese medicine resources, establishing the digital Chinese medicine plant herbarium and acquiring the documentary of the Chinese medicine resource survey. The content, procedures and methods of the video data collecting have been related and analyzed in this article to provide reference for the Chinese medicine resources survey.

  15. Image data acquisition and segmentation for accurate modeling of the calvarium

    Science.gov (United States)

    Eggers, Georg; Dauber, Sascha; Korb, Werner; Welzel, Thomas; Marmulla, Ruediger; Hassfeld, Stefan

    2004-05-01

    Accuracy of the patient-model is a critical point in robot assisted surgery. When performing craniotomies, the dura mater must not be perforated. Hence bone width is of particular interest. The influence of imaging and segmentation on accuracy of the width of the bone-model was investigated. A human cadaver head was scanned with a CT-scanner under a variety of image acquisition parameters. Bone was segmented from these image data sets using threshold based segmentation with different settings for the lower threshold. From these volume data sets surface models of the bone were generated. The real width of the bone of the skull was measured at several positions. Using fiducial marker registration, these measured values were compared to the corresponding positions in the bone-models. CT-scan imaging with a slice thickness and slice distance of 1.5 to 2mm and a segmentation of bone with a lower threshold of 300 or 400 Hounsfield Units resulted in models with an average accuracy of 0.4mm for bone-width. However, at some points these models were too thin by up to 0.9mm. More accurate models are needed. It has to be evaluated, whether CT imaging with higher resolution or more sophisticated segmentation algorithms can reduce the scatter.

  16. A Parallel Distributed-Memory Particle Method Enables Acquisition-Rate Segmentation of Large Fluorescence Microscopy Images.

    Directory of Open Access Journals (Sweden)

    Yaser Afshar

    Full Text Available Modern fluorescence microscopy modalities, such as light-sheet microscopy, are capable of acquiring large three-dimensional images at high data rate. This creates a bottleneck in computational processing and analysis of the acquired images, as the rate of acquisition outpaces the speed of processing. Moreover, images can be so large that they do not fit the main memory of a single computer. We address both issues by developing a distributed parallel algorithm for segmentation of large fluorescence microscopy images. The method is based on the versatile Discrete Region Competition algorithm, which has previously proven useful in microscopy image segmentation. The present distributed implementation decomposes the input image into smaller sub-images that are distributed across multiple computers. Using network communication, the computers orchestrate the collectively solving of the global segmentation problem. This not only enables segmentation of large images (we test images of up to 10(10 pixels, but also accelerates segmentation to match the time scale of image acquisition. Such acquisition-rate image segmentation is a prerequisite for the smart microscopes of the future and enables online data compression and interactive experiments.

  17. A Parallel Distributed-Memory Particle Method Enables Acquisition-Rate Segmentation of Large Fluorescence Microscopy Images.

    Science.gov (United States)

    Afshar, Yaser; Sbalzarini, Ivo F

    2016-01-01

    Modern fluorescence microscopy modalities, such as light-sheet microscopy, are capable of acquiring large three-dimensional images at high data rate. This creates a bottleneck in computational processing and analysis of the acquired images, as the rate of acquisition outpaces the speed of processing. Moreover, images can be so large that they do not fit the main memory of a single computer. We address both issues by developing a distributed parallel algorithm for segmentation of large fluorescence microscopy images. The method is based on the versatile Discrete Region Competition algorithm, which has previously proven useful in microscopy image segmentation. The present distributed implementation decomposes the input image into smaller sub-images that are distributed across multiple computers. Using network communication, the computers orchestrate the collectively solving of the global segmentation problem. This not only enables segmentation of large images (we test images of up to 10(10) pixels), but also accelerates segmentation to match the time scale of image acquisition. Such acquisition-rate image segmentation is a prerequisite for the smart microscopes of the future and enables online data compression and interactive experiments.

  18. A Spartan 6 FPGA-based data acquisition system for dedicated imagers in nuclear medicine

    Science.gov (United States)

    Fysikopoulos, E.; Loudos, G.; Georgiou, M.; David, S.; Matsopoulos, G.

    2012-12-01

    We present the development of a four-channel low-cost hardware system for data acquisition, with application in dedicated nuclear medicine imagers. A 12 bit octal channel high-speed analogue to digital converter, with up to 65 Msps sampling rate, was used for the digitization of analogue signals. The digitized data are fed into a field programmable gate array (FPGA), which contains an interface to a bank of double data rate 2 (DDR2)-type memory. The FPGA processes the digitized data and stores the results into the DDR2. An ethernet link was used for data transmission to a personal computer. The embedded system was designed using Xilinx's embedded development kit (EDK) and was based on Xilinx's Microblaze soft-core processor. The system has been evaluated using two different discrete optical detector arrays (a position-sensitive photomultiplier tube and a silicon photomultiplier) with two different pixelated scintillator arrays (BGO, LSO:Ce). The energy resolution for both detectors was approximately 25%. A clear identification of all crystal elements was achieved in all cases. The data rate of the system with this implementation can reach 60 Mbits s-1. The results have shown that this FPGA data acquisition system is a compact and flexible solution for single-photon-detection applications. This paper was originally submitted for inclusion in the special feature on Imaging Systems and Techniques 2011.

  19. Determination of rice canopy growth based on high resolution satellite images: a case study using RapidEye imagery in Korea

    Directory of Open Access Journals (Sweden)

    Mijeong Kim

    2016-10-01

    Full Text Available Processing to correct atmospheric effects and classify all constituent pixels in a remote sensing image is required before the image is used to monitor plant growth. The raw image contains artifacts due to atmospheric conditions at the time of acquisition. This study sought to distinguish the canopy growth of paddy rice using RapidEye (BlackBridge, Berlin, Germany satellite data and investigate practical image correction and classification methods. The RapidEye images were taken over experimental fields of paddy rice at Chonnam National University (CNU, Gwangju, and at TaeAn, Choongcheongnam-do, Korea. The CNU RapidEye images were used to evaluate the atmospheric correction methods. Atmospheric correction of the RapidEye images was performed using three different methods, QUick Atmospheric Correction (QUAC, Fast Line-of-sight Atmospheric Analysis of Spectral Hypercubes (FLAASH, and Atmospheric and Topographic Correction (ATCOR. To minimize errors in utilizing observed growth and yield estimation of paddy rice, the paddy fields were classified using a supervised classification method and normalized difference vegetation index (NDVI thresholds, using the NDVI time-series features of the paddy fields. The results of the atmospheric correction using ATCOR on the satellite images were favorable, which correspond to those from reference UAV images. Meanwhile, the classification method using the NDVI threshold accurately classified the same pixels from each of the time-series images. We have demonstrated that the image correction and classification methods investigated here should be applicable to high resolution satellite images used in monitoring other crop growth conditions.

  20. Clinical application of Half Fourier Acquisition Single Shot Turbo Spin Echo (HASTE) imaging accelerated by simultaneous multi-slice acquisition

    NARCIS (Netherlands)

    Schulz, J.; Marques, J.P.; Telgte, A. ter; Dorst, A van; Leeuw, H.F. de; Meijer, F.J.A.; Norris, D.G.

    2018-01-01

    Purpose As a single-shot sequence with a long train of refocusing pulses, Half-Fourier Acquisition Single-Shot Turbo-Spin-Echo (HASTE) suffers from high power deposition limiting use at high resolutions and high field strengths, particularly if combined with acceleration techniques such as

  1. Intraoperative Molecular Imaging for Rapid Assessment of Tumor Margins

    Science.gov (United States)

    2010-09-01

    determine the depth of embedded tumor fragments in the excise tissue or surgical cavity. Pilot animal data with the Licor IRDye800CW-2DG imaging agent in...and the tumor immediately removed with adjacent normal tissue. All tissue were soaked for 5 – 20 minutes in a solution of Licor IRDye800CW-2DG and... Licor IRDye800CW-2DG, showing a cross section of the tumor mass. These images show a significant amount of non-specific uptake of the probe in

  2. Data acquisition for knowledge-based image classification and interpretation of remotely sensed multispectral images

    Science.gov (United States)

    Simmeth, Robert-Josef; Spitzer, Hartwig H.

    1993-10-01

    An experiment is reported which had as its main requirement the gathering of a wide range of information about the scene under investigation. It took place at the area of the Nurnberg airport (Bavaria, West Germany) in the summer of 1991 and the spring of 1992. The time frame of the experiment was planned to get satellite images in addition to airborne images at nearly the same time. The airborne scanner provided images in eleven spectral channels from the visible to the thermal infrared with geometric resolutions between 0.75 m and 4.50 m. In parallel we performed several radiometric measurements of reference targets at the ground as well as meteorological measurements to take care of atmospheric effects and lighting conditions. To get a better knowledge of the whole area we gathered additional information of the Nurnberg airport and surroundings. In particular, we investigated the functionality and task of certain areas (airport, agricultural, and industrial) and the type of surface materials of objects (airplane, taxi way, park way, shed or hangar roof, natural surfaces) within the scene of investigation. A combination of vegetation filters, unsupervised classification, and gray scale morphological image processing was applied to the data. As a result we obtained pixel by pixel and morphological classification of buildings, roads, and vegetation.

  3. Monitoring of rapid sand filters using an acoustic imaging technique

    NARCIS (Netherlands)

    Allouche, N.; Simons, D.G.; Rietveld, L.C.

    2012-01-01

    A novel instrument is developed to acoustically image sand filters used for water treatment and monitor their performance. The instrument consists of an omnidirectional transmitter that generates a chirp with a frequency range between 10 and 110 kHz, and an array of hydrophones. The instrument was

  4. Rapid global fitting of large fluorescence lifetime imaging microscopy datasets.

    Directory of Open Access Journals (Sweden)

    Sean C Warren

    Full Text Available Fluorescence lifetime imaging (FLIM is widely applied to obtain quantitative information from fluorescence signals, particularly using Förster Resonant Energy Transfer (FRET measurements to map, for example, protein-protein interactions. Extracting FRET efficiencies or population fractions typically entails fitting data to complex fluorescence decay models but such experiments are frequently photon constrained, particularly for live cell or in vivo imaging, and this leads to unacceptable errors when analysing data on a pixel-wise basis. Lifetimes and population fractions may, however, be more robustly extracted using global analysis to simultaneously fit the fluorescence decay data of all pixels in an image or dataset to a multi-exponential model under the assumption that the lifetime components are invariant across the image (dataset. This approach is often considered to be prohibitively slow and/or computationally expensive but we present here a computationally efficient global analysis algorithm for the analysis of time-correlated single photon counting (TCSPC or time-gated FLIM data based on variable projection. It makes efficient use of both computer processor and memory resources, requiring less than a minute to analyse time series and multiwell plate datasets with hundreds of FLIM images on standard personal computers. This lifetime analysis takes account of repetitive excitation, including fluorescence photons excited by earlier pulses contributing to the fit, and is able to accommodate time-varying backgrounds and instrument response functions. We demonstrate that this global approach allows us to readily fit time-resolved fluorescence data to complex models including a four-exponential model of a FRET system, for which the FRET efficiencies of the two species of a bi-exponential donor are linked, and polarisation-resolved lifetime data, where a fluorescence intensity and bi-exponential anisotropy decay model is applied to the analysis

  5. Rapid global fitting of large fluorescence lifetime imaging microscopy datasets.

    Science.gov (United States)

    Warren, Sean C; Margineanu, Anca; Alibhai, Dominic; Kelly, Douglas J; Talbot, Clifford; Alexandrov, Yuriy; Munro, Ian; Katan, Matilda; Dunsby, Chris; French, Paul M W

    2013-01-01

    Fluorescence lifetime imaging (FLIM) is widely applied to obtain quantitative information from fluorescence signals, particularly using Förster Resonant Energy Transfer (FRET) measurements to map, for example, protein-protein interactions. Extracting FRET efficiencies or population fractions typically entails fitting data to complex fluorescence decay models but such experiments are frequently photon constrained, particularly for live cell or in vivo imaging, and this leads to unacceptable errors when analysing data on a pixel-wise basis. Lifetimes and population fractions may, however, be more robustly extracted using global analysis to simultaneously fit the fluorescence decay data of all pixels in an image or dataset to a multi-exponential model under the assumption that the lifetime components are invariant across the image (dataset). This approach is often considered to be prohibitively slow and/or computationally expensive but we present here a computationally efficient global analysis algorithm for the analysis of time-correlated single photon counting (TCSPC) or time-gated FLIM data based on variable projection. It makes efficient use of both computer processor and memory resources, requiring less than a minute to analyse time series and multiwell plate datasets with hundreds of FLIM images on standard personal computers. This lifetime analysis takes account of repetitive excitation, including fluorescence photons excited by earlier pulses contributing to the fit, and is able to accommodate time-varying backgrounds and instrument response functions. We demonstrate that this global approach allows us to readily fit time-resolved fluorescence data to complex models including a four-exponential model of a FRET system, for which the FRET efficiencies of the two species of a bi-exponential donor are linked, and polarisation-resolved lifetime data, where a fluorescence intensity and bi-exponential anisotropy decay model is applied to the analysis of live cell

  6. Direct Parametric Image Reconstruction in Reduced Parameter Space for Rapid Multi-Tracer PET Imaging.

    Science.gov (United States)

    Cheng, Xiaoyin; Li, Zhoulei; Liu, Zhen; Navab, Nassir; Huang, Sung-Cheng; Keller, Ulrich; Ziegler, Sibylle; Shi, Kuangyu

    2015-02-12

    The separation of multiple PET tracers within an overlapping scan based on intrinsic differences of tracer pharmacokinetics is challenging, due to limited signal-to-noise ratio (SNR) of PET measurements and high complexity of fitting models. In this study, we developed a direct parametric image reconstruction (DPIR) method for estimating kinetic parameters and recovering single tracer information from rapid multi-tracer PET measurements. This is achieved by integrating a multi-tracer model in a reduced parameter space (RPS) into dynamic image reconstruction. This new RPS model is reformulated from an existing multi-tracer model and contains fewer parameters for kinetic fitting. Ordered-subsets expectation-maximization (OSEM) was employed to approximate log-likelihood function with respect to kinetic parameters. To incorporate the multi-tracer model, an iterative weighted nonlinear least square (WNLS) method was employed. The proposed multi-tracer DPIR (MTDPIR) algorithm was evaluated on dual-tracer PET simulations ([18F]FDG and [11C]MET) as well as on preclinical PET measurements ([18F]FLT and [18F]FDG). The performance of the proposed algorithm was compared to the indirect parameter estimation method with the original dual-tracer model. The respective contributions of the RPS technique and the DPIR method to the performance of the new algorithm were analyzed in detail. For the preclinical evaluation, the tracer separation results were compared with single [18F]FDG scans of the same subjects measured 2 days before the dual-tracer scan. The results of the simulation and preclinical studies demonstrate that the proposed MT-DPIR method can improve the separation of multiple tracers for PET image quantification and kinetic parameter estimations.

  7. Acquisition and Processing Protocols for Uav Images: 3d Modeling of Historical Buildings Using Photogrammetry

    Science.gov (United States)

    Murtiyoso, A.; Koehl, M.; Grussenmeyer, P.; Freville, T.

    2017-08-01

    Photogrammetry has seen an increase in the use of UAVs (Unmanned Aerial Vehicles) for both large and smaller scale cartography. The use of UAVs is also advantageous because it may be used for tasks requiring quick response, including in the case of the inspection and monitoring of buildings. The objective of the project is to study the acquisition and processing protocols which exist in the literature and to adapt them for UAV projects. This implies a study on the calibration of the sensors, flight planning, comparison of software solutions, data management, and analysis on the different products of a UAV project. Two historical buildings of the city of Strasbourg were used as case studies: a part of the Rohan Palace façade and the St-Pierre-le-Jeune Catholic church. In addition, a preliminary test was performed on the Josephine Pavilion. Two UAVs were used in this research; namely the Sensefly Albris and the DJI Phantom 3 Professional. The experiments have shown that the calibration parameters tend to be unstable for small sensors. Furthermore, the dense matching of images remains a particular problem to address in a close range photogrammetry project, more so in the presence of noise on the images. Data management in cases where the number of images is high is also very important. The UAV is nevertheless a suitable solution for the surveying and recording of historical buildings because it is able to take images from points of view which are normally inaccessible to classical terrestrial techniques.

  8. Optimization of a shorter variable-acquisition time for legs to achieve true whole-body PET/CT images.

    Science.gov (United States)

    Umeda, Takuro; Miwa, Kenta; Murata, Taisuke; Miyaji, Noriaki; Wagatsuma, Kei; Motegi, Kazuki; Terauchi, Takashi; Koizumi, Mitsuru

    2017-12-01

    The present study aimed to qualitatively and quantitatively evaluate PET images as a function of acquisition time for various leg sizes, and to optimize a shorter variable-acquisition time protocol for legs to achieve better qualitative and quantitative accuracy of true whole-body PET/CT images. The diameters of legs to be modeled as phantoms were defined based on data derived from 53 patients. This study analyzed PET images of a NEMA phantom and three plastic bottle phantoms (diameter, 5.68, 8.54 and 10.7 cm) that simulated the human body and legs, respectively. The phantoms comprised two spheres (diameters, 10 and 17 mm) containing fluorine-18 fluorodeoxyglucose solution with sphere-to-background ratios of 4 at a background radioactivity level of 2.65 kBq/mL. All PET data were reconstructed with acquisition times ranging from 10 to 180, and 1200 s. We visually evaluated image quality and determined the coefficient of variance (CV) of the background, contrast and the quantitative %error of the hot spheres, and then determined two shorter variable-acquisition protocols for legs. Lesion detectability and quantitative accuracy determined based on maximum standardized uptake values (SUVmax) in PET images of a patient using the proposed protocols were also evaluated. A larger phantom and a shorter acquisition time resulted in increased background noise on images and decreased the contrast in hot spheres. A visual score of ≥ 1.5 was obtained when the acquisition time was ≥ 30 s for three leg phantoms, and ≥ 120 s for the NEMA phantom. The quantitative %errors of the 10- and 17-mm spheres in the leg phantoms were ± 15 and ± 10%, respectively, in PET images with a high CV (scan PET/CT assessment in the clinical setting.

  9. Implementation of an image acquisition and processing system based on FlexRIO, CameraLink and areaDetector

    Energy Technology Data Exchange (ETDEWEB)

    Esquembri, S.; Ruiz, M. [Instrumentation and Applied Acoustic Research Group, Technical University of Madrid (UPM), Madrid (Spain); Barrera, E., E-mail: eduardo.barrera@upm.es [Instrumentation and Applied Acoustic Research Group, Technical University of Madrid (UPM), Madrid (Spain); Sanz, D.; Bustos, A. [Instrumentation and Applied Acoustic Research Group, Technical University of Madrid (UPM), Madrid (Spain); Castro, R.; Vega, J. [National Fusion Laboratory, CIEMAT, Madrid (Spain)

    2016-11-15

    Highlights: • The system presented acquires and process images from any CameraLink compliant camera. • The frame grabber implanted with FlexRIO technology have image time stamping and preprocessing capabilities. • The system is integrated into EPICS using areaDetector for a flexible configuration of image the acquisition and processing chain. • Is fully compatible with the architecture of the ITER Fast Controllers. - Abstract: Image processing systems are commonly used in current physics experiments, such as nuclear fusion experiments. These experiments usually require multiple cameras with different resolutions, framerates and, frequently, different software drivers. The integration of heterogeneous types of cameras without a unified hardware and software interface increases the complexity of the acquisition system. This paper presents the implementation of a distributed image acquisition and processing system for CameraLink cameras. This system implements a camera frame grabber using Field Programmable Gate Arrays (FPGAs), a reconfigurable hardware platform that allows for image acquisition and real-time preprocessing. The frame grabber is integrated into Experimental Physics and Industrial Control System (EPICS) using the areaDetector EPICS software module, which offers a common interface shared among tens of cameras to configure the image acquisition and process these images in a distributed control system. The use of areaDetector also allows the image processing to be parallelized and concatenated using: multiple computers; areaDetector plugins; and the areaDetector standard type for data, NDArrays. The architecture developed is fully compatible with ITER Fast Controllers and the entire system has been validated using a camera hardware simulator that stream videos from fusion experiment databases.

  10. Correction of hemifacial microsomia with the help of mirror imaging and a rapid prototyping technique: case report.

    Science.gov (United States)

    Zhou, Libin; He, Lisheng; Shang, Hongtao; Liu, Guicai; Zhao, Jinlong; Liu, Yanpu

    2009-09-01

    A 23-year-old man presented with an 8-year history of unilateral hemifacial microsomia. A three-dimensional model of the maxillofacial bones was generated after acquisition of helical computed tomographic data. A customised implant model was designed by projecting a mirror image of the healthy mandible on to the three-dimensional model. A resin model of the implant was then made using a rapid prototyping machine. A polymeric biomaterial was sculpted according to the model and implanted into the affected side of the mandible to restore his facial symmetry. The hemifacial microsomia was corrected and a symmetrical facial contour obtained. No complications developed during the 6-year follow-up.

  11. Featured Image: Making a Rapidly Rotating Black Hole

    Science.gov (United States)

    Kohler, Susanna

    2017-10-01

    These stills from a simulation show the evolution (from left to right and top to bottom) of a high-mass X-ray binary over 1.1 days, starting after the star on the right fails to explode as a supernova and then collapses into a black hole. Many high-mass X-ray binaries like the well-known Cygnus X-1, the first source widely accepted to be a black hole host rapidly spinning black holes. Despite our observations of these systems, however, were still not sure how these objects end up with such high rotation speeds. Using simulations like that shown above, a team of scientists led by Aldo Batta (UC Santa Cruz) has demonstrated how a failed supernova explosion can result in such a rapidly spinning black hole. The authors work shows that in a binary where one star attempts to explode as a supernova and fails it doesnt succeed in unbinding the star the large amount of fallback material can interact with the companion star and then accrete onto the black hole, spinning it up in the process. You can read more about the authors simulations and conclusions in the paper below.CitationAldo Batta et al 2017 ApJL 846 L15. doi:10.3847/2041-8213/aa8506

  12. Rapid interferometric imaging of printed drug laden multilayer structures

    DEFF Research Database (Denmark)

    Sandler, Niklas; Kassamakov, Ivan; Ehlers, Henrik

    2014-01-01

    /and active pharmaceutical ingredients (API) adhere to each other. This is crucial in order to have predetermined drug release profiles. We also demonstrate non-invasive measurement of a polymer structure in a microfluidic channel. It shown that traceable interferometric 3D microscopy is a viable technique......The developments in printing technologies allow fabrication of micron-size nano-layered delivery systems to personal specifications. In this study we fabricated layered polymer structures for drug-delivery into a microfluidic channel and aimed to interferometrically assure their topography...... and adherence to each other. We present a scanning white light interferometer (SWLI) method for quantitative assurance of the topography of the embedded structure. We determined rapidly in non-destructive manner the thickness and roughness of the structures and whether the printed layers containing polymers or...

  13. Rapid identification of heterogeneous mixture components with hyperspectral coherent anti-Stokes Raman scattering imaging

    NARCIS (Netherlands)

    Garbacik, E.T.; Herek, Jennifer Lynn; Otto, Cornelis; Offerhaus, Herman L.

    2012-01-01

    For the rapid analysis of complicated heterogeneous mixtures, we have developed a method to acquire and intuitively display hyperspectral coherent anti-Stokes Raman scattering (CARS) images. The imaging is performed with a conventional optical setup based around an optical parametric oscillator.

  14. UAV PHOTOGRAMMETRY WITH OBLIQUE IMAGES: FIRST ANALYSIS ON DATA ACQUISITION AND PROCESSING

    Directory of Open Access Journals (Sweden)

    I. Aicardi

    2016-06-01

    Full Text Available In recent years, many studies revealed the advantages of using airborne oblique images for obtaining improved 3D city models (e.g. including façades and building footprints. Expensive airborne cameras, installed on traditional aerial platforms, usually acquired the data. The purpose of this paper is to evaluate the possibility of acquire and use oblique images for the 3D reconstruction of a historical building, obtained by UAV (Unmanned Aerial Vehicle and traditional COTS (Commercial Off-the-Shelf digital cameras (more compact and lighter than generally used devices, for the realization of high-level-of-detail architectural survey. The critical issues of the acquisitions from a common UAV (flight planning strategies, ground control points, check points distribution and measurement, etc. are described. Another important considered aspect was the evaluation of the possibility to use such systems as low cost methods for obtaining complete information from an aerial point of view in case of emergency problems or, as in the present paper, in the cultural heritage application field. The data processing was realized using SfM-based approach for point cloud generation: different dense image-matching algorithms implemented in some commercial and open source software were tested. The achieved results are analysed and the discrepancies from some reference LiDAR data are computed for a final evaluation. The system was tested on the S. Maria Chapel, a part of the Novalesa Abbey (Italy.

  15. Uav Photogrammetry with Oblique Images: First Analysis on Data Acquisition and Processing

    Science.gov (United States)

    Aicardi, I.; Chiabrando, F.; Grasso, N.; Lingua, A. M.; Noardo, F.; Spanò, A.

    2016-06-01

    In recent years, many studies revealed the advantages of using airborne oblique images for obtaining improved 3D city models (e.g. including façades and building footprints). Expensive airborne cameras, installed on traditional aerial platforms, usually acquired the data. The purpose of this paper is to evaluate the possibility of acquire and use oblique images for the 3D reconstruction of a historical building, obtained by UAV (Unmanned Aerial Vehicle) and traditional COTS (Commercial Off-the-Shelf) digital cameras (more compact and lighter than generally used devices), for the realization of high-level-of-detail architectural survey. The critical issues of the acquisitions from a common UAV (flight planning strategies, ground control points, check points distribution and measurement, etc.) are described. Another important considered aspect was the evaluation of the possibility to use such systems as low cost methods for obtaining complete information from an aerial point of view in case of emergency problems or, as in the present paper, in the cultural heritage application field. The data processing was realized using SfM-based approach for point cloud generation: different dense image-matching algorithms implemented in some commercial and open source software were tested. The achieved results are analysed and the discrepancies from some reference LiDAR data are computed for a final evaluation. The system was tested on the S. Maria Chapel, a part of the Novalesa Abbey (Italy).

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-03-31

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

  17. Phase incremented echo train acquisition applied to magnetic resonance pore imaging

    Science.gov (United States)

    Hertel, S. A.; Galvosas, P.

    2017-02-01

    Efficient phase cycling schemes remain a challenge for NMR techniques if the pulse sequences involve a large number of rf-pulses. Especially complex is the Carr Purcell Meiboom Gill (CPMG) pulse sequence where the number of rf-pulses can range from hundreds to several thousands. Our recent implementation of Magnetic Resonance Pore Imaging (MRPI) is based on a CPMG rf-pulse sequence in order to refocus the effect of internal gradients inherent in porous media. While the spin dynamics for spin- 1 / 2 systems in CPMG like experiments are well understood it is still not straight forward to separate the desired pathway from the spectrum of unwanted coherence pathways. In this contribution we apply Phase Incremented Echo Train Acquisition (PIETA) to MRPI. We show how PIETA offers a convenient way to implement a working phase cycling scheme and how it allows one to gain deeper insights into the amplitudes of undesired pathways.

  18. Data acquisition and processing system of the electron cyclotron emission imaging system of the KSTAR tokamak.

    Science.gov (United States)

    Kim, J B; Lee, W; Yun, G S; Park, H K; Domier, C W; Luhmann, N C

    2010-10-01

    A new innovative electron cyclotron emission imaging (ECEI) diagnostic system for the Korean Superconducting Tokamak Advanced Research (KSTAR) produces a large amount of data. The design of the data acquisition and processing system of the ECEI diagnostic system should consider covering the large data production and flow. The system design is based on the layered structure scalable to the future extension to accommodate increasing data demands. Software architecture that allows a web-based monitoring of the operation status, remote experiment, and data analysis is discussed. The operating software will help machine operators and users validate the acquired data promptly, prepare next discharge, and enhance the experiment performance and data analysis in a distributed environment.

  19. Thermal Imaging of the Waccasassa Bay Preserve: Image Acquisition and Processing

    Science.gov (United States)

    Raabe, Ellen A.; Bialkowska-Jelinska, Elzbieta

    2010-01-01

    Thermal infrared (TIR) imagery was acquired along coastal Levy County, Florida, in March 2009 with the goal of identifying groundwater-discharge locations in Waccasassa Bay Preserve State Park (WBPSP). Groundwater discharge is thermally distinct in winter when Floridan aquifer temperature, 71-72 degrees F, contrasts with the surrounding cold surface waters. Calibrated imagery was analyzed to assess temperature anomalies and related thermal traces. The influence of warm Gulf water and image artifacts on small features was successfully constrained by image evaluation in three separate zones: Creeks, Bay, and Gulf. Four levels of significant water-temperature anomalies were identified, and 488 sites of interest were mapped. Among the sites identified, at least 80 were determined to be associated with image artifacts and human activity, such as excavation pits and the Florida Barge Canal. Sites of interest were evaluated for geographic concentration and isolation. High site densities, indicating interconnectivity and prevailing flow, were located at Corrigan Reef, No. 4 Channel, Winzy Creek, Cow Creek, Withlacoochee River, and at excavation sites. In other areas, low to moderate site density indicates the presence of independent vents and unique flow paths. A directional distribution assessment of natural seep features produced a northwest trend closely matching the strike direction of regional faults. Naturally occurring seeps were located in karst ponds and tidal creeks, and several submerged sites were detected in Waccasassa River and Bay, representing the first documentation of submarine vents in the Waccasassa region. Drought conditions throughout the region placed constraints on positive feature identification. Low discharge or displacement by landward movement of saltwater may have reduced or reversed flow during this season. Approximately two-thirds of seep locations in the overlap between 2009 and 2005 TIR night imagery were positively re-identified in 2009

  20. "MASSIVE" brain dataset: Multiple acquisitions for standardization of structural imaging validation and evaluation.

    Science.gov (United States)

    Froeling, Martijn; Tax, Chantal M W; Vos, Sjoerd B; Luijten, Peter R; Leemans, Alexander

    2017-05-01

    In this work, we present the MASSIVE (Multiple Acquisitions for Standardization of Structural Imaging Validation and Evaluation) brain dataset of a single healthy subject, which is intended to facilitate diffusion MRI (dMRI) modeling and methodology development. MRI data of one healthy subject (female, 25 years) were acquired on a clinical 3 Tesla system (Philips Achieva) with an eight-channel head coil. In total, the subject was scanned on 18 different occasions with a total acquisition time of 22.5 h. The dMRI data were acquired with an isotropic resolution of 2.5 mm3 and distributed over five shells with b-values up to 4000 s/mm2 and two Cartesian grids with b-values up to 9000 s/mm2 . The final dataset consists of 8000 dMRI volumes, corresponding B0 field maps and noise maps for subsets of the dMRI scans, and ten three-dimensional FLAIR, T1 -, and T2 -weighted scans. The average signal-to-noise-ratio of the non-diffusion-weighted images was roughly 35. This unique set of in vivo MRI data will provide a robust framework to evaluate novel diffusion processing techniques and to reliably compare different approaches for diffusion modeling. The MASSIVE dataset is made publically available (both unprocessed and processed) on www.massive-data.org. Magn Reson Med 77:1797-1809, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  1. Development of rapid methods for relaxation time mapping and motion estimation using magnetic resonance imaging

    OpenAIRE

    Gilani, Syed Irtiza Ali

    2008-01-01

    Recent technological developments in the field of magnetic resonance imaging have resulted in advanced techniques that can reduce the total time to acquire images. For applications such as relaxation time mapping, which enables improved visualisation of in vivo structures, rapid imaging techniques are highly desirable. TAPIR is a Look- Locker-based sequence for high-resolution, multislice T1 relaxation time mapping. Despite the high accuracy and precision of TAPIR, an improveme...

  2. Clinical evaluation of reducing acquisition time on single-photon emission computed tomography image quality using proprietary resolution recovery software.

    Science.gov (United States)

    Aldridge, Matthew D; Waddington, Wendy W; Dickson, John C; Prakash, Vineet; Ell, Peter J; Bomanji, Jamshed B

    2013-11-01

    A three-dimensional model-based resolution recovery (RR) reconstruction algorithm that compensates for collimator-detector response, resulting in an improvement in reconstructed spatial resolution and signal-to-noise ratio of single-photon emission computed tomography (SPECT) images, was tested. The software is said to retain image quality even with reduced acquisition time. Clinically, any improvement in patient throughput without loss of quality is to be welcomed. Furthermore, future restrictions in radiotracer supplies may add value to this type of data analysis. The aims of this study were to assess improvement in image quality using the software and to evaluate the potential of performing reduced time acquisitions for bone and parathyroid SPECT applications. Data acquisition was performed using the local standard SPECT/CT protocols for 99mTc-hydroxymethylene diphosphonate bone and 99mTc-methoxyisobutylisonitrile parathyroid SPECT imaging. The principal modification applied was the acquisition of an eight-frame gated data set acquired using an ECG simulator with a fixed signal as the trigger. This had the effect of partitioning the data such that the effect of reduced time acquisitions could be assessed without conferring additional scanning time on the patient. The set of summed data sets was then independently reconstructed using the RR software to permit a blinded assessment of the effect of acquired counts upon reconstructed image quality as adjudged by three experienced observers. Data sets reconstructed with the RR software were compared with the local standard processing protocols; filtered back-projection and ordered-subset expectation-maximization. Thirty SPECT studies were assessed (20 bone and 10 parathyroid). The images reconstructed with the RR algorithm showed improved image quality for both full-time and half-time acquisitions over local current processing protocols (Pquality compared with local processing protocols and has been introduced into

  3. Rapid FLIM: The new and innovative method for ultra-fast imaging of biological processes (Conference Presentation)

    Science.gov (United States)

    Orthaus-Mueller, Sandra; Kraemer, Benedikt; Tannert, Astrid; Roehlicke, Tino; Wahl, Michael; Rahn, Hans-Juergen; Koberling, Felix; Erdmann, Rainer

    2017-02-01

    Over the last two decades, time-resolved fluorescence microscopy has become an essential tool in Life Sciences thanks to measurement procedures such as Fluorescence Lifetime Imaging (FLIM), lifetime based Foerster Resonance Energy Transfer (FRET), and Fluorescence (Lifetime) Correlation Spectroscopy (F(L)CS) down to the single molecule level. Today, complete turn-key systems are available either as stand-alone units or as upgrades for confocal laser scanning microscopes (CLSM). Data acquisition on such systems is typically based on Time-Correlated Single Photon Counting (TCSPC) electronics along with picosecond pulsed diode lasers as excitation sources and highly sensitive, single photon counting detectors. Up to now, TCSPC data acquisition is considered a somewhat slow process as a large number of photons per pixel is required for reliable data analysis, making it difficult to use FLIM for following fast FRET processes, such as signal transduction pathways in cells or fast moving sub-cellular structures. We present here a novel and elegant solution to tackle this challenge. Our approach, named rapidFLIM, exploits recent hardware developments such as TCSPC modules with ultra short dead times and hybrid photomultiplier detector assemblies enabling significantly higher detection count rates. Thanks to these improved components, it is possible to achieve much better photon statistics in significantly shorter time spans while being able to perform FLIM imaging for fast processes in a qualitative manner and with high optical resolution. FLIM imaging can now be performed with up to several frames per second making it possible to study fast processes such as protein interactions involved in endosome trafficking.

  4. Implementing an accurate and rapid sparse sampling approach for low-dose atomic resolution STEM imaging

    Science.gov (United States)

    Kovarik, L.; Stevens, A.; Liyu, A.; Browning, N. D.

    2016-10-01

    While aberration correction for scanning transmission electron microscopes (STEMs) dramatically increased the spatial resolution obtainable in the images of materials that are stable under the electron beam, the practical resolution of many STEM images is now limited by the sample stability rather than the microscope. To extract physical information from the images of beam sensitive materials, it is becoming clear that there is a critical dose/dose-rate below which the images can be interpreted as representative of the pristine material, while above it the observation is dominated by beam effects. Here, we describe an experimental approach for sparse sampling in the STEM and in-painting image reconstruction in order to reduce the electron dose/dose-rate to the sample during imaging. By characterizing the induction limited rise-time and hysteresis in the scan coils, we show that a sparse line-hopping approach to scan randomization can be implemented that optimizes both the speed of the scan and the amount of the sample that needs to be illuminated by the beam. The dose and acquisition time for the sparse sampling is shown to be effectively decreased by at least a factor of 5× relative to conventional acquisition, permitting imaging of beam sensitive materials to be obtained without changing the microscope operating parameters. The use of sparse line-hopping scan to acquire STEM images is demonstrated with atomic resolution aberration corrected the Z-contrast images of CaCO3, a material that is traditionally difficult to image by TEM/STEM because of dosage issues.

  5. Sparse-SEMAC: rapid and improved SEMAC metal implant imaging using SPARSE-SENSE acceleration.

    Science.gov (United States)

    Otazo, Ricardo; Nittka, Mathias; Bruno, Mary; Raithel, Esther; Geppert, Christian; Gyftopoulos, Soterios; Recht, Michael; Rybak, Leon

    2017-07-01

    To develop an accelerated SEMAC metal implant MRI technique (Sparse-SEMAC) with reduced scan time and improved metal distortion correction. Sparse-SEMAC jointly exploits the inherent sparsity along the additional phase-encoding dimension and multicoil encoding capabilities to significantly accelerate data acquisition. A prototype pulse sequence with pseudorandom ky -kz undersampling and an inline image reconstruction was developed for integration in clinical studies. Three patients with hip implants were imaged using the proposed Sparse-SEMAC with eight-fold acceleration and compared with the standard-SEMAC technique used in clinical studies (three-fold GRAPPA acceleration). Measurements were performed with SEMAC-encoding steps (SES) = 15 for Sparse-SEMAC and SES = 9 for Standard-SEMAC using high spatial resolution Proton Density (PD) and lower-resolution STIR acquisitions. Two expert musculoskeletal (MSK) radiologists performed a consensus reading to score image-quality parameters. Sparse-SEMAC enables up to eight-fold acceleration of data acquisition that results in two-fold scan time reductions, compared with Standard-SEMAC, with improved metal artifact correction for patients with hip implants without degrading spatial resolution. The high acceleration enabled by Sparse-SEMAC would enable clinically feasible examination times with improved correction of metal distortion. Magn Reson Med 78:79-87, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  6. Coil concepts for rapid and motion-compensated MR-Imaging of small animals; Spulenkonzepte zur schnellen und bewegungskompensierten MR-Bildgebung von Kleintieren

    Energy Technology Data Exchange (ETDEWEB)

    Korn, Matthias

    2009-05-06

    In this work radiofrequency-coils for the imaging of small animals in clinical whole-body MRI-systems were developed. Therefore in a first step single-channel solenoids were designed and characterized. The solenoids had two and three windings respectively, which were implemented as double wires to increase the homogeneity of the receive profile. These coils allow the acquisition of whole-body images of mice with high signal-to-noise ratio and homogeneity over a distance of at least 6.3 cm. Since many imaging experiments require rapid image acquisition, in the next step a novel coil concept was developed, which, due to its geometry, enables parallel imaging in arbitrary directions. A prototype was assembled and tested on phantom and small-animal experiments. With an accelerating factor of R=2, the difference of the SNR in all directions from the theoretical maximum, was less than 1%. In order to compensate physiological motion by the self-gating technique, in this work a coil is presented for the first time, which selectively amplifies the self-gating signal, while - due to a optical detuning technique - preserving the homogeneous illumination of the image. In vivo experiments on a small animal show an amplification of the self-gating signal by at least 40%. (orig.)

  7. Accuracy for predicting adhesion between meningioma and the brain by using brain surface motion imaging: comparison between single and double acquisition methods

    Energy Technology Data Exchange (ETDEWEB)

    Taoka, Toshiaki; Sakamoto, Masahiko; Akashi, Toshiaki; Miyasaka, Toshiteru; Ochi, Tomoko; Wada, Takeshi; Kichikawa, Kimihiko [Nara Medical University, Department of Radiology, Kashihara, Nara (Japan); Yamada, Syuichi; Nakase, Hiroyuki [Nara Medical University, Department of Neurosurgery, Kashihara, Nara (Japan); Uchikoshi, Masato [Siemens Japan K.K., Tokyo (Japan)

    2012-12-15

    The presence of adhesions between the brain and the meningioma is an important factor that determines the success of total surgical removal. Brain surface motion imaging enables assessment of the dynamics of brain surface motion. A subtraction image of pulse-gated heavily T2-weighted images in different phases of the cardiac cycle provides a stripe pattern on the surface of the pulsating brain. Thus, the lack of a stripe pattern on the surface of extraaxial tumor indicates the presence of tumor-brain adhesion. The purpose of the present experiment was to evaluate the accuracy of predicting tumor-brain adhesion using the original double acquisition method and the improved single acquisition method. The subjects were 67 meningioma cases patients who were surgically treated after brain surface motion imaging. Thirty-three cases were evaluated using the double acquisition method and 34 cases were evaluated with the single acquisition method. In the double acquisition method, the two sets of images are acquired as two independent scans, and in the single acquisition method, the images are acquired serially as a single scan. The findings for the double acquisition method agreed with the surgical findings in 23 cases (69.7 %), while findings from the single acquisition method agreed with the surgical findings in 26 cases (76.5 %). Pre-surgical evaluation for tumor-brain adhesion by brain surface motion imaging provides helpful information for meningioma surgery, especially when using the single acquisition method. (orig.)

  8. Hardware Timestamping for an Image Acquisition System Based on FlexRIO and IEEE 1588 v2 Standard

    Science.gov (United States)

    Esquembri, S.; Sanz, D.; Barrera, E.; Ruiz, M.; Bustos, A.; Vega, J.; Castro, R.

    2016-02-01

    Current fusion devices usually implement distributed acquisition systems for the multiple diagnostics of their experiments. However, each diagnostic is composed by hundreds or even thousands of signals, including images from the vessel interior. These signals and images must be correctly timestamped, because all the information will be analyzed to identify plasma behavior using temporal correlations. For acquisition devices without synchronization mechanisms the timestamp is given by another device with timing capabilities when signaled by the first device. Later, each data should be related with its timestamp, usually via software. This critical action is unfeasible for software applications when sampling rates are high. In order to solve this problem this paper presents the implementation of an image acquisition system with real-time hardware timestamping mechanism. This is synchronized with a master clock using the IEEE 1588 v2 Precision Time Protocol (PTP). Synchronization, image acquisition and processing, and timestamping mechanisms are implemented using Field Programmable Gate Array (FPGA) and a timing card -PTP v2 synchronized. The system has been validated using a camera simulator streaming videos from fusion databases. The developed architecture is fully compatible with ITER Fast Controllers and has been integrated with EPICS to control and monitor the whole system.

  9. Quantum dot imaging in the second near-infrared optical window: studies on reflectance fluorescence imaging depths by effective fluence rate and multiple image acquisition.

    Science.gov (United States)

    Jung, Yebin; Jeong, Sanghwa; Nayoun, Won; Ahn, Boeun; Kwag, Jungheon; Geol Kim, Sang; Kim, Sungjee

    2015-04-01

    Quantum dot (QD) imaging capability was investigated by the imaging depth at a near-infrared second optical window (SOW; 1000 to 1400 nm) using time-modulated pulsed laser excitations to control the effective fluence rate. Various media, such as liquid phantoms, tissues, and in vivo small animals, were used and the imaging depths were compared with our predicted values. The QD imaging depth under excitation of continuous 20 mW/cm(2) laser was determined to be 10.3 mm for 2 wt%hemoglobin phantom medium and 5.85 mm for 1 wt% intralipid phantom, which were extended by more than two times on increasing the effective fluence rate to 2000 mW/cm(2). Bovine liver and porcine skin tissues also showed similar enhancement in the contrast-to-noise ratio (CNR) values. A QD sample was inserted into the abdomen of a mouse.With a higher effective fluence rate, the CNR increased more than twofold and the QD sample became clearly visualized, which was completely undetectable under continuous excitation.Multiple acquisitions of QD images and averaging process pixel by pixel were performed to overcome the thermal noise issue of the detector in SOW, which yielded significant enhancement in the imaging capability, showing up to a 1.5 times increase in the CNR.

  10. Rapid biocompatibility analysis of materials via in vivo fluorescence imaging of mouse models.

    Directory of Open Access Journals (Sweden)

    Kaitlin M Bratlie

    Full Text Available BACKGROUND: Many materials are unsuitable for medical use because of poor biocompatibility. Recently, advances in the high throughput synthesis of biomaterials has significantly increased the number of potential biomaterials, however current biocompatibility analysis methods are slow and require histological analysis. METHODOLOGY/PRINCIPAL FINDINGS: Here we develop rapid, non-invasive methods for in vivo quantification of the inflammatory response to implanted biomaterials. Materials were placed subcutaneously in an array format and monitored for host responses as per ISO 10993-6: 2001. Host cell activity in response to these materials was imaged kinetically, in vivo using fluorescent whole animal imaging. Data captured using whole animal imaging displayed similar temporal trends in cellular recruitment of phagocytes to the biomaterials compared to histological analysis. CONCLUSIONS/SIGNIFICANCE: Histological analysis similarity validates this technique as a novel, rapid approach for screening biocompatibility of implanted materials. Through this technique there exists the possibility to rapidly screen large libraries of polymers in vivo.

  11. The 2014 Broadband Acquisition and Imaging Operation (BAcIO) at Stromboli Volcano (Italy)

    Science.gov (United States)

    Scarlato, P.; Taddeucci, J.; Del Bello, E.; Gaudin, D.; Ricci, T.; Andronico, D.; Lodato, L.; Cannata, A.; Ferrari, F.; Orr, T. R.; Sesterhenn, J.; Plescher, R.; Baumgärtel, Y.; Harris, A. J. L.; Bombrun, M.; Barnie, T. D.; Houghton, B. F.; Kueppers, U.; Capponi, A.

    2014-12-01

    In May 2014, Stromboli volcano, one of the best natural laboratories for the study of weak explosive volcanism, hosted a large combination of state-of-the-art and prototype eruption monitoring technologies. Aiming to expand our parameterization capabilities for explosive eruption dynamics, we temporarily deployed in direct view of the active vents a range of imaging, acoustic, and seismic data acquisition systems. Imaging systems included: two high-speed visible cameras acquiring synchronized images at 500 and 1000 frames per second (fps); two thermal infrared forward looking (FLIR) cameras zooming into the active vents and acquiring at 50-200 fps; two FLIR cameras acquiring at lower (3-50 fps) frame rates with a broader field of view; one visible time-lapse camera; one UV camera system for the measurement of sulphur dioxide emission; and one drone equipped with a camcorder. Acoustic systems included: four broadband microphones (range of tens of kHz to 0.1 Hz), two of them co-located with one of the high-speed cameras and one co-located with one of the seismometers (see below); and an acoustic microphone array. This array included sixteen microphones with a circular arrangement located on a steep slope above the active vents. Seismic systems included two broadband seismometers, one of them co-located with one of the high-speed cameras, and one co-located with one of the microphones. The above systems were synchronized with a variety of methods, and temporarily added to the permanent monitoring networks already operating on the island. Observation focus was on pyroclast ejection processes extending from the shallow conduit, through their acceleration and interaction with the atmosphere, and to their dispersal and deposition. The 3-D distribution of bombs, the sources of jet noise in the explosions, the comparison between methods for estimating explosion properties, and the relations between erupted gas and magma volumes, are some examples of the processes targeted

  12. Wavelength optimization for rapid chromophore mapping using spatial frequency domain imaging

    Science.gov (United States)

    Mazhar, Amaan; Dell, Steven; Cuccia, David J.; Gioux, Sylvain; Durkin, Anthony J.; Frangioni, John V.; Tromberg, Bruce J.

    2010-11-01

    Spatial frequency-domain imaging (SFDI) utilizes multiple-frequency structured illumination and model-based computation to generate two-dimensional maps of tissue absorption and scattering properties. SFDI absorption data are measured at multiple wavelengths and used to fit for the tissue concentration of intrinsic chromophores in each pixel. This is done with a priori knowledge of the basis spectra of common tissue chromophores, such as oxyhemoglobin (ctO2Hb), deoxyhemoglobin (ctHHb), water (ctH2O), and bulk lipid. The quality of in vivo SFDI fits for the hemoglobin parameters ctO2Hb and ctHHb is dependent on wavelength selection, fitting parameters, and acquisition rate. The latter is critical because SFDI acquisition time is up to six times longer than planar two-wavelength multispectral imaging due to projection of multiple-frequency spatial patterns. Thus, motion artifact during in vivo measurements compromises the quality of the reconstruction. Optimal wavelength selection is examined through matrix decomposition of basis spectra, simulation of data, and dynamic in vivo measurements of a human forearm during cuff occlusion. Fitting parameters that minimize cross-talk from additional tissue chromophores, such as water and lipid, are determined. On the basis of this work, a wavelength pair of 670 nm/850 nm is determined to be the optimal two-wavelength combination for in vivo hemodynamic tissue measurements provided that assumptions for water and lipid fractions are made in the fitting process. In our SFDI case study, wavelength optimization reduces acquisition time over 30-fold to 1.5s compared to 50s for a full 34-wavelength acquisition. The wavelength optimization enables dynamic imaging of arterial occlusions with improved spatial resolution due to reduction of motion artifacts.

  13. Single-Trial Event-Related Potential Based Rapid Image Triage System

    Directory of Open Access Journals (Sweden)

    Ke Yu

    2011-06-01

    Full Text Available Searching for points of interest (POI in large-volume imagery is a challenging problem with few good solutions. In this work, a neural engineering approach called rapid image triage (RIT which could offer about a ten-fold speed up in POI searching is developed. It is essentially a cortically-coupled computer vision technique, whereby the user is presented bursts of images at a speed of 6–15 images per second and then neural signals called event-related potential (ERP is used as the ‘cue’ for user seeing images of high relevance likelihood. Compared to past efforts, the implemented system has several unique features: (1 it applies overlapping frames in image chip preparation, to ensure rapid image triage performance; (2 a novel common spatial-temporal pattern (CSTP algorithm that makes use of both spatial and temporal patterns of ERP topography is proposed for high-accuracy single-trial ERP detection; (3 a weighted version of probabilistic support-vector-machine (SVM is used to address the inherent unbalanced nature of single-trial ERP detection for RIT. High accuracy, fast learning, and real-time capability of the developed system shown on 20 subjects demonstrate the feasibility of a brainmachine integrated rapid image triage system for fast detection of POI from large-volume imagery.

  14. Rapid, low dose X-ray diffractive imaging of the malaria parasite Plasmodium falciparum

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Michael W.M., E-mail: michael.jones@latrobe.edu.au [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Dearnley, Megan K. [ARC Centre of Excellence for Coherent X-Ray Science, Department of Biochemistry and Molecular Biology, Bio21 Institute, The University of Melbourne, Victoria 3010 (Australia); Riessen, Grant A. van [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Abbey, Brian [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Melbourne Centre for Nanofabrication, Victoria 3168 (Australia); Putkunz, Corey T. [ARC Centre of Excellence for Coherent X-Ray Science, School of Physics, The University of Melbourne, Victoria 3010 (Australia); Junker, Mark D. [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Vine, David J. [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); McNulty, Ian [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); Centre for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Nugent, Keith A. [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Peele, Andrew G. [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Australian Synchrotron, 800 Blackburn Road, Clayton 3168 (Australia); Tilley, Leann [ARC Centre of Excellence for Coherent X-Ray Science, Department of Biochemistry and Molecular Biology, Bio21 Institute, The University of Melbourne, Victoria 3010 (Australia)

    2014-08-01

    Phase-diverse X-ray coherent diffractive imaging (CDI) provides a route to high sensitivity and spatial resolution with moderate radiation dose. It also provides a robust solution to the well-known phase-problem, making on-line image reconstruction feasible. Here we apply phase-diverse CDI to a cellular sample, obtaining images of an erythrocyte infected by the sexual stage of the malaria parasite, Plasmodium falciparum, with a radiation dose significantly lower than the lowest dose previously reported for cellular imaging using CDI. The high sensitivity and resolution allow key biological features to be identified within intact cells, providing complementary information to optical and electron microscopy. This high throughput method could be used for fast tomographic imaging, or to generate multiple replicates in two-dimensions of hydrated biological systems without freezing or fixing. This work demonstrates that phase-diverse CDI is a valuable complementary imaging method for the biological sciences and ready for immediate application. - Highlights: • Phase-diverse coherent X-ray diffraction microscopy provides high-resolution and high-contrast images of intact biological samples. • Rapid nanoscale resolution imaging is demonstrated at orders of magnitude lower dose than previously possible. • Phase-diverse coherent X-ray diffraction microscopy is a robust technique for rapid, quantitative, and correlative X-ray phase imaging.

  15. Characterisation and correction of signal fluctuations in successive acquisitions of microarray images

    Directory of Open Access Journals (Sweden)

    François Nicolas

    2009-03-01

    Full Text Available Abstract Background There are many sources of variation in dual labelled microarray experiments, including data acquisition and image processing. The final interpretation of experiments strongly relies on the accuracy of the measurement of the signal intensity. For low intensity spots in particular, accurately estimating gene expression variations remains a challenge as signal measurement is, in this case, highly subject to fluctuations. Results To evaluate the fluctuations in the fluorescence intensities of spots, we used series of successive scans, at the same settings, of whole genome arrays. We measured the decrease in fluorescence and we evaluated the influence of different parameters (PMT gain, resolution and chemistry of the slide on the signal variability, at the level of the array as a whole and by intensity interval. Moreover, we assessed the effect of averaging scans on the fluctuations. We found that the extent of photo-bleaching was low and we established that 1 the fluorescence fluctuation is linked to the resolution e.g. it depends on the number of pixels in the spot 2 the fluorescence fluctuation increases as the scanner voltage increases and, moreover, is higher for the red as opposed to the green fluorescence which can introduce bias in the analysis 3 the signal variability is linked to the intensity level, it is higher for low intensities 4 the heterogeneity of the spots and the variability of the signal and the intensity ratios decrease when two or three scans are averaged. Conclusion Protocols consisting of two scans, one at low and one at high PMT gains, or multiple scans (ten scans can introduce bias or be difficult to implement. We found that averaging two, or at most three, acquisitions of microarrays scanned at moderate photomultiplier settings (PMT gain is sufficient to significantly improve the accuracy (quality of the data and particularly those for spots having low intensities and we propose this as a general

  16. Rapid 3D Reconstruction for Image Sequence Acquired from UAV Camera

    Directory of Open Access Journals (Sweden)

    Yufu Qu

    2018-01-01

    Full Text Available In order to reconstruct three-dimensional (3D structures from an image sequence captured by unmanned aerial vehicles’ camera (UAVs and improve the processing speed, we propose a rapid 3D reconstruction method that is based on an image queue, considering the continuity and relevance of UAV camera images. The proposed approach first compresses the feature points of each image into three principal component points by using the principal component analysis method. In order to select the key images suitable for 3D reconstruction, the principal component points are used to estimate the interrelationships between images. Second, these key images are inserted into a fixed-length image queue. The positions and orientations of the images are calculated, and the 3D coordinates of the feature points are estimated using weighted bundle adjustment. With this structural information, the depth maps of these images can be calculated. Next, we update the image queue by deleting some of the old images and inserting some new images into the queue, and a structural calculation of all the images can be performed by repeating the previous steps. Finally, a dense 3D point cloud can be obtained using the depth–map fusion method. The experimental results indicate that when the texture of the images is complex and the number of images exceeds 100, the proposed method can improve the calculation speed by more than a factor of four with almost no loss of precision. Furthermore, as the number of images increases, the improvement in the calculation speed will become more noticeable.

  17. Rapid 3D Reconstruction for Image Sequence Acquired from UAV Camera.

    Science.gov (United States)

    Qu, Yufu; Huang, Jianyu; Zhang, Xuan

    2018-01-14

    In order to reconstruct three-dimensional (3D) structures from an image sequence captured by unmanned aerial vehicles' camera (UAVs) and improve the processing speed, we propose a rapid 3D reconstruction method that is based on an image queue, considering the continuity and relevance of UAV camera images. The proposed approach first compresses the feature points of each image into three principal component points by using the principal component analysis method. In order to select the key images suitable for 3D reconstruction, the principal component points are used to estimate the interrelationships between images. Second, these key images are inserted into a fixed-length image queue. The positions and orientations of the images are calculated, and the 3D coordinates of the feature points are estimated using weighted bundle adjustment. With this structural information, the depth maps of these images can be calculated. Next, we update the image queue by deleting some of the old images and inserting some new images into the queue, and a structural calculation of all the images can be performed by repeating the previous steps. Finally, a dense 3D point cloud can be obtained using the depth-map fusion method. The experimental results indicate that when the texture of the images is complex and the number of images exceeds 100, the proposed method can improve the calculation speed by more than a factor of four with almost no loss of precision. Furthermore, as the number of images increases, the improvement in the calculation speed will become more noticeable.

  18. Do the eyes scan dream images during rapid eye movement sleep? Evidence from the rapid eye movement sleep behaviour disorder model.

    Science.gov (United States)

    Leclair-Visonneau, Laurène; Oudiette, Delphine; Gaymard, Bertrand; Leu-Semenescu, Smaranda; Arnulf, Isabelle

    2010-06-01

    Rapid eye movements and complex visual dreams are salient features of human rapid eye movement sleep. However, it remains to be elucidated whether the eyes scan dream images, despite studies that have retrospectively compared the direction of rapid eye movements to the dream recall recorded after having awakened the sleeper. We used the model of rapid eye movement sleep behaviour disorder (when patients enact their dreams by persistence of muscle tone) to determine directly whether the eyes move in the same directions as the head and limbs. In 56 patients with rapid eye movement sleep behaviour disorder and 17 healthy matched controls, the eye movements were monitored by electrooculography in four (right, left, up and down) directions, calibrated with a target and synchronized with video and sleep monitoring. The rapid eye movement sleep behaviour disorder-associated behaviours occurred 2.1 times more frequently during rapid eye movement sleep with than without rapid eye movements, and more often during or after rapid eye movements than before. Rapid eye movement density, index and complexity were similar in patients with rapid eye movement sleep behaviour disorder and controls. When rapid eye movements accompanied goal-oriented motor behaviour during rapid eye movement sleep behaviour disorder (e.g. grabbing a fictive object, hand greetings, climbing a ladder), which happened in 19 sequences, 82% were directed towards the action of the patient (same plane and direction). When restricted to the determinant rapid eye movements, the concordance increased to 90%. Rapid eye movements were absent in 38-42% of behaviours. This directional coherence between limbs, head and eye movements during rapid eye movement sleep behaviour disorder suggests that, when present, rapid eye movements imitate the scanning of the dream scene. Since the rapid eye movements are similar in subjects with and without rapid eye movement sleep behaviour disorder, this concordance can be extended

  19. The effects of image acquisition control of digital X-ray system on radiodensity quantification

    Directory of Open Access Journals (Sweden)

    Wook-Jin Seong,

    2013-08-01

    Full Text Available Objectives Aluminum step wedge (ASW equivalent radiodensity (eRD has been used to quantify restorative material's radiodensity. The aim of this study was to evaluate the effects of image acquisition control (IAC of a digital X-ray system on the radiodensity quantification under different exposure time settings. Materials and Methods Three 1-mm thick restorative material samples with various opacities were prepared. Samples were radiographed alongside an ASW using one of three digital radiographic modes (linear mapping (L, nonlinear mapping (N, and nonlinear mapping and automatic exposure control activated (E under 3 exposure time settings (underexposure, normal-exposure, and overexposure. The ASW eRD of restorative materials, attenuation coefficients and contrasts of ASW, and the correlation coefficient of linear relationship between logarithms of gray-scale value and thicknesses of ASW were compared under 9 conditions. Results The ASW eRD measurements of restorative materials by three digital radiographic modes were statistically different (p = 0.049 but clinically similar. The relationship between logarithms of background corrected grey scale value and thickness of ASW was highly linear but attenuation coefficients and contrasts varied significantly among 3 radiographic modes. Varying exposure times did not affect ASW eRD significantly. Conclusions Even though different digital radiographic modes induced large variation on attenuation of coefficient and contrast of ASW, E mode improved diagnostic quality of the image significantly under the under-exposure condition by improving contrasts, while maintaining ASW eRDs of restorative materials similar. Under the condition of this study, underexposure time may be acceptable clinically with digital X-ray system using automatic gain control that reduces radiation exposure for patient.

  20. SPR platform based on image acquisition for HER2 antigen detection

    Science.gov (United States)

    Monteiro, Johny P.; Predabon, Sheila M.; Bonafé, Elton G.; Martins, Alessandro F.; Brolo, Alexandre G.; Radovanovic, Eduardo; Girotto, Emerson M.

    2017-01-01

    HER2 antigen is a marker used for breast cancer diagnosis and prevention. Its determination has great importance since breast cancer is one of the most insidious types of cancer in women. HER2 antigen assessment in human serum is traditionally achieved by enzyme-linked immunosorbent assay (ELISA method), but it has some disadvantages, such as suppressing the thermodynamic-kinetic studies regarding the antibody-antigen interaction, and the use of labeled molecules that can promote false positive responses. Biosensors based on surface plasmon resonance (SPR) are sensitive optical techniques widely applied on bioassays. The plasmonic devices do not operate with labeled molecules, overcoming conventional immunoassay limitations, and enabling a direct detection of target analytes. In this way, a new SPR biosensor to assess HER2 antigen has been proposed, using nanohole arrays on a gold thin film by signal transduction of transmitted light measurements from array image acquisitions. These metallic nanostructures may couple the light directly on surface plasmons using a simple collinear arrangement. The proposed device reached an average sensitivity for refractive index (RI) variation on a metal surface of 4146 intensity units/RIU (RIU = RI units). The device feasibility on biomolecular assessment was evaluated. For this, 3 ng ml-1 known HER2 antigen concentration was efficiently flowed (using a microfluidic system) and detected from aqueous solutions. This outcome shows that the device may be a powerful apparatus for bioassays, particularly toward breast cancer diagnosis and prognosis.

  1. Three-dimensional imaging of ventilation dynamics in asthmatics using multiecho projection acquisition with constrained reconstruction.

    Science.gov (United States)

    Holmes, James H; O'Halloran, Rafael L; Brodsky, Ethan K; Bley, Thorsten A; Francois, Christopher J; Velikina, Julia V; Sorkness, Ronald L; Busse, William W; Fain, Sean B

    2009-12-01

    The purpose of this work is to detect dynamic gas trapping in three dimensions during forced exhalation at isotropic high spatial resolution and high temporal resolution using hyperpolarized helium-3 MRI. Ten subjects underwent hyperpolarized helium-3 MRI and multidetector CT. MRI was performed throughout inspiration, breath-hold, and forced expiration. A multiecho three-dimensional projection acquisition was used to improve data collection efficiency and an iterative constrained reconstruction was implemented to improve signal to noise ratio (SNR) and increase robustness to motion. Two radiologists evaluated the dynamic MRI and breath-held multidetector CT data for gas and air trapping, respectively. Phantom studies showed the proposed technique significantly improved depiction of moving objects compared to view-sharing methods. Gas trapping was detected using MRI in five of the six asthmatic subjects who displayed air trapping with multidetector CT. Locations in disagreement were found to represent small to moderate regions of air trapping. The proposed technique provides whole-lung three-dimensional imaging of respiration dynamics at high spatial and temporal resolution and compares well to the current standard, multidetector CT. While multidetector CT can provide information about static regional air trapping, it is unable to depict dynamics in a setting more comparable to a spirometry maneuver and explore the longitudinal time evolution of the trapped regions. (c) 2009 Wiley-Liss, Inc.

  2. Rapid identification of salmonella serotypes with stereo and hyperspectral microscope imaging Methods

    Science.gov (United States)

    The hyperspectral microscope imaging (HMI) method can reduce detection time within 8 hours including incubation process. The early and rapid detection with this method in conjunction with the high throughput capabilities makes HMI method a prime candidate for implementation for the food industry. Th...

  3. Click-Chemistry-Mediated Rapid Microbubble Capture for Acute Thrombus Ultrasound Molecular Imaging.

    Science.gov (United States)

    Wang, Tuantuan; Yuan, Chuxiao; Dai, Bingyang; Liu, Yang; Li, Mingxi; Feng, Zhenqiang; Jiang, Qing; Xu, Zhihong; Zhao, Ningwei; Gu, Ning; Yang, Fang

    2017-07-18

    Bioorthogonal coupling chemistry has been studied as a potentially advantageous approach for molecular imaging because it offers rapid, efficient, and strong binding, which might also benefit stability, production, and chemical conjugation. The inverse-electron-demand Diels-Alder reaction between a 1,2,4,5-tetrazine and trans-cyclooctene (TCO) is an example of a highly selective and rapid bioorthogonal coupling reaction that has been used successfully to prepare targeted molecular imaging probes. Here we report a fast, reliable, and highly sensitive approach, based on a two-step pretargeting bioorthogonal approach, to achieving activated-platelet-specific CD62p-targeted thrombus ultrasound molecular imaging. Tetrazine-modified microbubbles (tetra-MBs) could be uniquely and rapidly captured by subsequent click chemistry of thrombus tagged with a trans-cyclooctene-pretreated CD62p antibody. Moreover, such tetra-MBs showed great long-term stability under physiological conditions, thus offering the ability to monitor thrombus changes in real time. We demonstrated for the first time that a bioorthogonal targeting molecular ultrasound imaging strategy based on tetra-MBs could be a simple but powerful tool for rapid diagnosis of acute thrombosis. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Optimal Anesthetic Regime for Motionless Three-Dimensional Image Acquisition During Longitudinal Studies of Adult Nonpigmented Zebrafish.

    Science.gov (United States)

    Lockwood, Nicola; Parker, Jennifer; Wilson, Carole; Frankel, Paul

    2017-04-01

    With many live imaging techniques, it is crucial that a deep level of anesthesia is reached and maintained throughout image acquisition without reducing zebrafish viability. This is particularly true for three-dimensional tomographic imaging modalities. Currently, the most commonly used anesthetic in the zebrafish community, MS-222 (tricaine methanesulfonate), does not allow this. We show, using a combination of both MS-222 and isoflurane, that we can significantly improve the anesthetic regime required for motionless image acquisition of live adult zebrafish. We have benchmarked this against the requirements of our novel quantitative imaging platform, compressive sensing optical projection tomography. Using nonpigmented transgenic zebrafish, we show that a combination of 175 ppm of both anesthetics improves the maintenance of deep anesthesia for prolonged periods of time and it can be used repeatedly to enable longitudinal imaging. Importantly, it does not affect the health or viability of the adult zebrafish. We also show that nonpigmented fish, with a mutated form of the gene transparent, took significantly longer to reach deep anesthesia. The anesthetic regime presented in this study should lead to significant improvements in accuracy and information achievable from imaging live adult zebrafish and in its application to longitudinal studies.

  5. Rapid eye movement sleep behavior disorder in Parkinson's disease: magnetic resonance imaging study.

    Science.gov (United States)

    Ford, Andrew H; Duncan, Gordon W; Firbank, Michael J; Yarnall, Alison J; Khoo, Tien K; Burn, David J; O'Brien, John T

    2013-06-01

    Rapid eye movement sleep behavior disorder has poor prognostic implications for Parkinson's disease. The authors recruited 124 patients with early Parkinson's disease to compare clinical and neuroimaging findings based on the presence of this sleep disorder. The presence of rapid eye movement sleep behavior disorder was assessed with the Mayo Sleep Questionnaire. Magnetic resonance imaging sequences were obtained for voxel-based morphometry and diffusion tensor imaging. Patients with sleep disorder had more advanced disease, but groups had similar clinical characteristics and cognitive performance. Those with sleep disorder had areas of reduced cortical grey matter volume and white matter changes compared with those who did not have sleep disorder. However, differences were slight and were not significant when the analyses were adjusted for multiple comparisons. Rapid eye movement sleep behavior disorder was associated with subtle changes in white matter integrity and grey matter volume in patients with early Parkinson's disease. Copyright © 2013 Movement Disorder Society.

  6. Rapid Multi-Tracer PET Tumor Imaging With 18F-FDG and Secondary Shorter-Lived Tracers

    OpenAIRE

    Black, Noel F.; McJames, Scott; Kadrmas, Dan J

    2009-01-01

    Rapid multi-tracer PET, where two to three PET tracers are rapidly scanned with staggered injections, can recover certain imaging measures for each tracer based on differences in tracer kinetics and decay. We previously showed that single-tracer imaging measures can be recovered to a certain extent from rapid dual-tracer 62Cu – PTSM (blood flow) + 62Cu — ATSM (hypoxia) tumor imaging. In this work, the feasibility of rapidly imaging 18F-FDG plus one or two of these shorter-lived secondary trac...

  7. Sagittal Fresh Blood Imaging with Interleaved Acquisition of Systolic and Diastolic Data for Improved Robustness to Motion

    Science.gov (United States)

    Atanasova, Iliyana P.; Kim, Daniel; Storey, Pippa; Rosenkrantz, Andrew B; Lim, Ruth P.; Lee, Vivian S.

    2012-01-01

    Purpose To improve robustness to patient motion of ‘fresh blood imaging’ (FBI) for lower extremity non-contrast MRA. Methods In FBI, two sets of 3D fast spin echo images are acquired at different cardiac phases and subtracted to generate bright-blood angiograms. Routinely performed with a single coronal slab and sequential acquisition of systolic and diastolic data, FBI is prone to subtraction errors due to patient motion. In this preliminary feasibility study, FBI was implemented with two sagittal imaging slabs, and the systolic and diastolic acquisitions were interleaved to minimize sensitivity to motion. The proposed technique was evaluated in volunteers and patients. Results In ten volunteers, imaged while performing controlled movements, interleaved FBI demonstrated better tolerance to subject motion than sequential FBI. In one patient with peripheral arterial disease, interleaved FBI offered better depiction of collateral flow by reducing sensitivity to inadvertent motion. Conclusions FBI with interleaved acquisition of diastolic and systolic data in two sagittal imaging slabs offers improved tolerance to patient motion. PMID:23300129

  8. Retrospective 4D MR image construction from free-breathing slice Acquisitions: A novel graph-based approach.

    Science.gov (United States)

    Tong, Yubing; Udupa, Jayaram K; Ciesielski, Krzysztof C; Wu, Caiyun; McDonough, Joseph M; Mong, David A; Campbell, Robert M

    2017-01-01

    Dynamic or 4D imaging of the thorax has many applications. Both prospective and retrospective respiratory gating and tracking techniques have been developed for 4D imaging via CT and MRI. For pediatric imaging, due to radiation concerns, MRI becomes the de facto modality of choice. In thoracic insufficiency syndrome (TIS), patients often suffer from extreme malformations of the chest wall, diaphragm, and/or spine with inability of the thorax to support normal respiration or lung growth (Campbell et al., 2003, Campbell and Smith, 2007), as such patient cooperation needed by some of the gating and tracking techniques are difficult to realize without causing patient discomfort and interference with the breathing mechanism itself. Therefore (ventilator-supported) free-breathing MRI acquisition is currently the best choice for imaging these patients. This, however, raises a question of how to create a consistent 4D image from such acquisitions. This paper presents a novel graph-based technique for compiling the best 4D image volume representing the thorax over one respiratory cycle from slice images acquired during unencumbered natural tidal-breathing of pediatric TIS patients. In our approach, for each coronal (or sagittal) slice position, images are acquired at a rate of about 200-300ms/slice over several natural breathing cycles which yields over 2000 slices. A weighted graph is formed where each acquired slice constitutes a node and the weight of the arc between two nodes defines the degree of contiguity in space and time of the two slices. For each respiratory phase, an optimal 3D spatial image is constructed by finding the best path in the graph in the spatial direction. The set of all such 3D images for a given respiratory cycle constitutes a 4D image. Subsequently, the best 4D image among all such constructed images is found over all imaged respiratory cycles. Two types of evaluation studies are carried out to understand the behavior of this algorithm and in

  9. Imaging thiol redox status in murine tumors in vivo with rapid-scan electron paramagnetic resonance

    Science.gov (United States)

    Epel, Boris; Sundramoorthy, Subramanian V.; Krzykawska-Serda, Martyna; Maggio, Matthew C.; Tseytlin, Mark; Eaton, Gareth R.; Eaton, Sandra S.; Rosen, Gerald M.; Kao, Joseph P. Y.; Halpern, Howard J.

    2017-03-01

    Thiol redox status is an important physiologic parameter that affects the success or failure of cancer treatment. Rapid scan electron paramagnetic resonance (RS EPR) is a novel technique that has shown higher signal-to-noise ratio than conventional continuous-wave EPR in in vitro studies. Here we used RS EPR to acquire rapid three-dimensional images of the thiol redox status of tumors in living mice. This work presents, for the first time, in vivo RS EPR images of the kinetics of the reaction of 2H,15N-substituted disulfide-linked dinitroxide (PxSSPx) spin probe with intracellular glutathione. The cleavage rate is proportional to the intracellular glutathione concentration. Feasibility was demonstrated in a FSa fibrosarcoma tumor model in C3H mice. Similar to other in vivo and cell model studies, decreasing intracellular glutathione concentration by treating mice with L-buthionine sulfoximine (BSO) markedly altered the kinetic images.

  10. Relationship between diverse patient body size- and image acquisition-related factors, and quantitative and qualitative image quality in coronary computed tomography angiography: a multicenter observational study.

    Science.gov (United States)

    Utsunomiya, Daisuke; Tanaka, Ryoichi; Yoshioka, Kunihiro; Awai, Kazuo; Mochizuki, Teruhito; Matsunaga, Naofumi; Ichikawa, Tomoaki; Kanematsu, Masayuki; Kim, Tonsok; Yamashita, Yasuyuki

    2016-08-01

    We investigated the effects of patient- and image acquisition-related factors on the image quality in coronary CT angiography (CCTA). We enrolled 1197 patients (728 men; 65 ± 12 years). All underwent CCTA under the routine scan protocol in 23 participating hospitals. The subjective image quality (3-point Likert scale: excellent, good, and poor) and the attenuation of the left and right coronary artery (LCA, RCA) were recorded; the effects of patient and image acquisition-related factors on vascular attenuation were then compared. The mean LCA attenuation was 515.2 ± 65.8 (excellent), 401.4 ± 63.4 (good), and 319.5 ± 47.6 HU (poor). The corresponding RCA attenuation was 496.6 ± 67.6, 390.5 ± 58.5, and 308.5 ± 50.7 HU, respectively. Univariate analysis revealed significant associations between sufficient coronary attenuation (> 400 HU) and the age, gender, body surface area (BSA), number of detectors, contrast synchronization, scan mode, and the fractional contrast dose. Multivariate analysis revealed that the bolus tracking method, prospective electrocardiogram gating, and fractional contrast dose were significantly associated with sufficient coronary enhancement. BSA and fractional contrast dose are the most important patient- and image acquisition-related factors for sufficient coronary attenuation in CCTA.

  11. Usefulness of the SPACE pulse sequence at 1.5T MR cholangiography: comparison of image quality and image acquisition time with conventional 3D-TSE sequence.

    Science.gov (United States)

    Nakaura, Takeshi; Kidoh, Masafumi; Maruyama, Natsuki; Kawahara, Tetsuya; Namimoto, Tomohiro; Sakai, Yoshinari; Harada, Kazunori; Yamashita, Yasuyuki

    2013-11-01

    To prospectively evaluate the image quality and image acquisition time at 3D magnetic resonance cholangiopancreatography (MRCP) using sampling perfection with application optimized contrasts (SPACE) and conventional turbo-spin-echo (TSE) sequences. We acquired navigator-triggered SPACE and conventional 3D-TSE MRCP images using the same parameters where possible for 30 patients and compared the image acquisition time, contrast, and contrast-to-noise ratio (CNR) of the common bile duct (CBD). Two radiologists performed qualitative analyses using a 4-point scale. Image acquisition time was 31% shorter with the SPACE than the conventional TSE sequence (248.9 ± 73.0 sec vs. 360.5 ± 99.9 sec, P TSE (39.4 ± 14.7 vs. 33.5 ± 14.2, P TSE sequence; there was a significant difference in motion artifacts and the depiction of the CBD and the left hepatic and main pancreatic duct (P TSE. Copyright © 2013 Wiley Periodicals, Inc.

  12. Easy Leaf Area: Automated Digital Image Analysis for Rapid and Accurate Measurement of Leaf Area

    Directory of Open Access Journals (Sweden)

    Hsien Ming Easlon

    2014-07-01

    Full Text Available Premise of the study: Measurement of leaf areas from digital photographs has traditionally required significant user input unless backgrounds are carefully masked. Easy Leaf Area was developed to batch process hundreds of Arabidopsis rosette images in minutes, removing background artifacts and saving results to a spreadsheet-ready CSV file. Methods and Results: Easy Leaf Area uses the color ratios of each pixel to distinguish leaves and calibration areas from their background and compares leaf pixel counts to a red calibration area to eliminate the need for camera distance calculations or manual ruler scale measurement that other software methods typically require. Leaf areas estimated by this software from images taken with a camera phone were more accurate than ImageJ estimates from flatbed scanner images. Conclusions: Easy Leaf Area provides an easy-to-use method for rapid measurement of leaf area and nondestructive estimation of canopy area from digital images.

  13. Automated Formosat Image Processing System for Rapid Response to International Disasters

    Science.gov (United States)

    Cheng, M. C.; Chou, S. C.; Chen, Y. C.; Chen, B.; Liu, C.; Yu, S. J.

    2016-06-01

    FORMOSAT-2, Taiwan's first remote sensing satellite, was successfully launched in May of 2004 into the Sun-synchronous orbit at 891 kilometers of altitude. With the daily revisit feature, the 2-m panchromatic, 8-m multi-spectral resolution images captured have been used for researches and operations in various societal benefit areas. This paper details the orchestration of various tasks conducted in different institutions in Taiwan in the efforts responding to international disasters. The institutes involved including its space agency-National Space Organization (NSPO), Center for Satellite Remote Sensing Research of National Central University, GIS Center of Feng-Chia University, and the National Center for High-performance Computing. Since each institution has its own mandate, the coordinated tasks ranged from receiving emergency observation requests, scheduling and tasking of satellite operation, downlink to ground stations, images processing including data injection, ortho-rectification, to delivery of image products. With the lessons learned from working with international partners, the FORMOSAT Image Processing System has been extensively automated and streamlined with a goal to shorten the time between request and delivery in an efficient manner. The integrated team has developed an Application Interface to its system platform that provides functions of search in archive catalogue, request of data services, mission planning, inquiry of services status, and image download. This automated system enables timely image acquisition and substantially increases the value of data product. Example outcome of these efforts in recent response to support Sentinel Asia in Nepal Earthquake is demonstrated herein.

  14. Low-dose micro-CT imaging for vascular segmentation and analysis using sparse-view acquisitions.

    Directory of Open Access Journals (Sweden)

    Bert Vandeghinste

    Full Text Available The aim of this study is to investigate whether reliable and accurate 3D geometrical models of the murine aortic arch can be constructed from sparse-view data in vivo micro-CT acquisitions. This would considerably reduce acquisition time and X-ray dose. In vivo contrast-enhanced micro-CT datasets were reconstructed using a conventional filtered back projection algorithm (FDK, the image space reconstruction algorithm (ISRA and total variation regularized ISRA (ISRA-TV. The reconstructed images were then semi-automatically segmented. Segmentations of high- and low-dose protocols were compared and evaluated based on voxel classification, 3D model diameters and centerline differences. FDK reconstruction does not lead to accurate segmentation in the case of low-view acquisitions. ISRA manages accurate segmentation with 1024 or more projection views. ISRA-TV needs a minimum of 256 views. These results indicate that accurate vascular models can be obtained from micro-CT scans with 8 times less X-ray dose and acquisition time, as long as regularized iterative reconstruction is used.

  15. Large area super-resolution chemical imaging via rapid dithering of a nanoprobe

    Science.gov (United States)

    Languirand, Eric R.; Cullum, Brian M.

    2015-05-01

    Super-resolution chemical imaging via Raman spectroscopy provides a significant ability to simultaneously or pseudosimultaneously monitor numerous label-free analytes while elucidating their spatial distribution on the surface of the sample. However, spontaneous Raman is an inherently weak phenomenon making trace detection and thus superresolution imaging extremely difficult, if not impossible. To circumvent this and allow for trace detection of the few chemical species present in any sub-diffraction limited resolution element of an image, we have developed a surface enhanced Raman scattering (SERS) coherent fiber-optic imaging bundle probe consisting of 30,000 individual fiber elements. When the probes are tapered, etched and coated with metal, they provide circular Raman chemical images of a sample with a field of view of approximately 20μm (i.e. diameter) via the array of 30,000 individual 50 nm fiber elements. An acousto-optic tunable filter is used to rapidly scan or select discrete frequencies for multi- or hyperspectral analysis. Although the 50nm fiber element dimensions of this probe inherently provide spatial resolutions of approximately 100nm, further increases in the spatial resolution can be achieved by using a rapid dithering process. Using this process, additional images are obtained one-half fiber diameter translations in the x- and y- planes. A piezostage drives the movement, providing the accurate and reproducible shifts required for dithering. Optimal probability algorithms are then used to deconvolute the related images producing a final image with a three-fold increase in spatial resolution. This paper describes super-resolution chemical imaging using these probes and the dithering method as well as its potential applications in label-free imaging of lipid rafts and other applications within biology and forensics.

  16. Time-resolved optical imaging through turbid media using a fast data acquisition system based on a gated CCD camera

    Energy Technology Data Exchange (ETDEWEB)

    D' Andrea, Cosimo; Comelli, Daniela; Pifferi, Antonio; Torricelli, Alessandro; Valentini, Gianluca; Cubeddu, Rinaldo [INFM-Dipartimento di Fisica and IFN-CNR, Politecnico di Milano Piazza Leonardo da Vinci 32, I-20133 Milan (Italy)

    2003-07-21

    In this paper, we propose a novel approach for the acquisition of time-resolved data for optical tomography. A fast gated CCD has been used as a parallel detector to acquire in one shot the light intensity exiting a phantom within a very short time slice. By using a pulsed illumination and repeating the acquisition at different delays, the time behaviour of the diffused transmittance can be recorded very quickly. Scattering inclusions embedded in a 5 cm thick phantom have been revealed by fitting a set of 120 images, delayed 50 ps from one another, with a mathematical model based on the random walk theory. Moreover, absorption inclusions have been detected in time-gated images taken at suitable delays.

  17. AOTF-based near-infrared imaging spectrometer for rapid identification of camouflaged target

    Science.gov (United States)

    Gao, Zhifan; Zeng, Libo; Wu, Qiongshui

    2014-11-01

    Acousto-optic tunable filter (AOTF) is a novel device for spectrometer. The electronic tunability qualifies it with the most compelling advantages of higher wavelength scan rate over the conventional spectrometers that are mechanically tuned, and the feature of large angular aperture makes the AOTF particularly suitable in imaging applications. In this research, an AOTF-based near-infrared imaging spectrometer was developed. The spectrometer consists of a TeO2 AOTF module, a near-infrared imaging lens assembly, an AOTF controller, an InGaAs array detector, an image acquisition card, and a PC. A precisely designed optical wedge is placed at the emergent surface of the AOTF to deal with the inherent dispersion of the TeO2 that may degrade the spatial resolution. The direct digital synthesizer (DDS) techniques and the phase locked loop (PLL) techniques are combined for radio frequency (RF) signal synthesis. The PLL is driven by the DDS to take advantage of both their merits of high frequency resolution, high frequency scan rate and strong spurious signals resistance capability. All the functions relating to wavelength scan, image acquisition, processing, storge and display are controlled by the PC. Calibration results indicate that the spectral range is 898~1670 nm, the spectral resolution is 6.8 nm(@1064 nm), the wavelength separation between frames in the spectral image assembly is 1.0 nm, and the processing time of a single image is less than 1 ms if a TV camera with 640×512 detector is incorporated. A prototype device was assembled to test the capability of differentiating samples with similar appearances, and satisfactory results were achieved. By this device, the chemical compositions and the distribution information can be obtained simultaneously. This system has the most advantages of no moving parts, fast wavelength scan and strong vibration resistance. The proposed imaging spectrometer has a significant application prospect in the area of identification of

  18. Enhancement of multimodality texture-based prediction models via optimization of PET and MR image acquisition protocols: a proof of concept

    Science.gov (United States)

    Vallières, Martin; Laberge, Sébastien; Diamant, André; El Naqa, Issam

    2017-11-01

    Texture-based radiomic models constructed from medical images have the potential to support cancer treatment management via personalized assessment of tumour aggressiveness. While the identification of stable texture features under varying imaging settings is crucial for the translation of radiomics analysis into routine clinical practice, we hypothesize in this work that a complementary optimization of image acquisition parameters prior to texture feature extraction could enhance the predictive performance of texture-based radiomic models. As a proof of concept, we evaluated the possibility of enhancing a model constructed for the early prediction of lung metastases in soft-tissue sarcomas by optimizing PET and MR image acquisition protocols via computerized simulations of image acquisitions with varying parameters. Simulated PET images from 30 STS patients were acquired by varying the extent of axial data combined per slice (‘span’). Simulated T 1-weighted and T 2-weighted MR images were acquired by varying the repetition time and echo time in a spin-echo pulse sequence, respectively. We analyzed the impact of the variations of PET and MR image acquisition parameters on individual textures, and we investigated how these variations could enhance the global response and the predictive properties of a texture-based model. Our results suggest that it is feasible to identify an optimal set of image acquisition parameters to improve prediction performance. The model constructed with textures extracted from simulated images acquired with a standard clinical set of acquisition parameters reached an average AUC of 0.84 +/- 0.01 in bootstrap testing experiments. In comparison, the model performance significantly increased using an optimal set of image acquisition parameters (p = 0.04 ), with an average AUC of 0.89 +/- 0.01 . Ultimately, specific acquisition protocols optimized to generate superior radiomics measurements for a given clinical problem could be developed

  19. After Nearly A Decade Of Rapid Growth, Use And Complexity Of Imaging Declined, 2008-14.

    Science.gov (United States)

    Levin, David C; Parker, Laurence; Palit, Charles D; Rao, Vijay M

    2017-04-01

    Imaging is an important cost driver in health care, and its use grew rapidly in the early 2000s. Several studies toward the end of the decade suggested that a leveling off was beginning to occur. In this study we examined more recent data to determine whether the slowdown had continued. Our data sources were the nationwide Medicare Part B databases for the period 2001-14. We calculated utilization rates per 1,000 enrollees for all advanced imaging modalities. We also calculated professional component relative value unit (RVU) rates per 1,000 beneficiaries for all imaging modalities, as RVU values provide a measure of complexity of imaging services and may in some ways be a better reflection of the amount of work involved in imaging. We found that utilization rates and RVU rates grew substantially until 2008 and 2009, respectively, and then began to drop. The downward trend in both rates persisted through 2014. Federal policies appear to have achieved the desired effect of ending the rapid growth of imaging that had been seen in earlier years. Project HOPE—The People-to-People Health Foundation, Inc.

  20. Rapid profiling of polymeric phenolic acids in Salvia miltiorrhiza by hybrid data-dependent/targeted multistage mass spectrometry acquisition based on expected compounds prediction and fragment ion searching.

    Science.gov (United States)

    Shen, Yao; Feng, Zijin; Yang, Min; Zhou, Zhe; Han, Sumei; Hou, Jinjun; Li, Zhenwei; Wu, Wanying; Guo, De-An

    2018-01-15

    Phenolic acids are the major water-soluble components in Salvia miltiorrhiza (> 5%). According to previous studies, many of them contribute to the cardiovascular effects and antioxidant effects of S. miltiorrhiza. Polymeric phenolic acids can be considered as the tanshinol derived metabolites, e.g., dimmers, trimers and tetramers. A strategy combined with tanshinol-based expected compounds prediction, total ion chromatogram filtering, Fragment Ion Searching and parent list-based multistage mass spectrometry acquisition by Linear Trap Quadropole-orbitrap Velos Mass Spectrometry was proposed to rapid profile polymeric phenolic acids in S. miltiorrhiza. More than 480 potential polymeric phenolic acids could be screened out by this strategy. Based on the fragment information obtained by parent list-activated data dependent multistage mass spectrometry acquisition, 190 polymeric phenolic acids were characterized by comparing their mass information with literature data, and 18 of them were firstly detected from S. miltiorrhiza. Seven potential compounds were tentatively characterized as new polymeric phenolic acids from S. miltiorrhiza. This strategy facilitates identification of polymeric phenolic acids in complex matrix with both selectivity and sensitivity, which could be expanded for rapid discovery and identification of compounds from complex matrix. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. Evaluation of rapid volume changes of substrate-adherent cells by conventional microscopy 3D imaging.

    Science.gov (United States)

    Boudreault, F; Grygorczyk, R

    2004-09-01

    Precise measurement of rapid volume changes of substrate-adherent cells is essential to understand many aspects of cell physiology, yet techniques to evaluate volume changes with sufficient precision and high temporal resolution are limited. Here, we describe a novel imaging method that surveys the rapid morphology modifications of living, substrate-adherent cells based on phase-contrast, digital video microscopy. Cells grown on a glass substrate are mounted in a custom-designed, side-viewing chamber and subjected to hypotonic swelling. Side-view images of the rapidly swelling cell, and at the end of the assay, an image of the same cell viewed from a perpendicular direction through the substrate, are acquired. Based on these images, off-line reconstruction of 3D cell morphology is performed, which precisely measures cell volume, height and surface at different points during cell volume changes. Volume evaluations are comparable to those obtained by confocal laser scanning microscopy (DeltaVolume microscopy without the need for cell staining or intense illumination to monitor cell volume make this system a promising new tool to investigate the fundamentals of cell volume physiology.

  2. Rapid Sequential in Situ Multiplexing with DNA Exchange Imaging in Neuronal Cells and Tissues.

    Science.gov (United States)

    Wang, Yu; Woehrstein, Johannes B; Donoghue, Noah; Dai, Mingjie; Avendaño, Maier S; Schackmann, Ron C J; Zoeller, Jason J; Wang, Shan Shan H; Tillberg, Paul W; Park, Demian; Lapan, Sylvain W; Boyden, Edward S; Brugge, Joan S; Kaeser, Pascal S; Church, George M; Agasti, Sarit S; Jungmann, Ralf; Yin, Peng

    2017-10-11

    To decipher the molecular mechanisms of biological function, it is critical to map the molecular composition of individual cells or even more importantly tissue samples in the context of their biological environment in situ. Immunofluorescence (IF) provides specific labeling for molecular profiling. However, conventional IF methods have finite multiplexing capabilities due to spectral overlap of the fluorophores. Various sequential imaging methods have been developed to circumvent this spectral limit but are not widely adopted due to the common limitation of requiring multirounds of slow (typically over 2 h at room temperature to overnight at 4 °C in practice) immunostaining. We present here a practical and robust method, which we call DNA Exchange Imaging (DEI), for rapid in situ spectrally unlimited multiplexing. This technique overcomes speed restrictions by allowing for single-round immunostaining with DNA-barcoded antibodies, followed by rapid (less than 10 min) buffer exchange of fluorophore-bearing DNA imager strands. The programmability of DEI allows us to apply it to diverse microscopy platforms (with Exchange Confocal, Exchange-SIM, Exchange-STED, and Exchange-PAINT demonstrated here) at multiple desired resolution scales (from ∼300 nm down to sub-20 nm). We optimized and validated the use of DEI in complex biological samples, including primary neuron cultures and tissue sections. These results collectively suggest DNA exchange as a versatile, practical platform for rapid, highly multiplexed in situ imaging, potentially enabling new applications ranging from basic science, to drug discovery, and to clinical pathology.

  3. Acquisition-weighted chemical shift imaging improves SLOOP quantification of human cardiac phosphorus metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Geier, Oliver [Oslo University Hospital (Norway). The Intervention Centre; Weng, Andreas Max; Toepell, Andreas; Hahn, Dietbert [Wuerzburg Univ. (Germany). Inst. of Radiology; Spindler, Matthias [Wuerzburg Univ. (Germany). Dept. of Internal Medicine; Beer, Meinrad [Wuerzburg Univ. (Germany). Inst. of Radiology; Medical Univ. Graz (Austria). Dept. of Pediatric Radiology; Koestler, Herbert [Wuerzburg Univ. (Germany). Inst. of Radiology; Wuerzburg Univ. (Germany). Comprehensive Heart Failure Center

    2014-03-01

    Purpose: Phosphorous metabolite ratios in human myocardium were determined by a combination of acquisition weighted CSI and a SLOOP evaluation and the results were compared to corresponding SLOOP experiments using standard CSI. Materials and Methods: 10 healthy subjects were examined at 1.5 T using both standard CSI and acquisition weighted CSI. Both experiments were performed with a similar acquisition time and the same spatial resolution. The PCr/ATP ratio was determined and the localization properties of both experiments were compared. Results: The PCr/ATP ratio of 2.2 ± 0.4 found for the experiment using acquisition weighted CSI was almost identical to the value of 2.0 ± 0.4 for standard CSI. The sensitivity and the localization properties improved in all subjects using SLOOP evaluation of the acquisition weighted sampling in comparison to the standard CSI acquisition with an average of 3% and 18%, respectively. Conclusion: The employment of acquisition weighting allows for a further improvement of the {sup 31}P SLOOP spectroscopy of the human heart. (orig.)

  4. Multi-Frequency Encoding for Rapid Color Flow and Quadroplex Imaging

    DEFF Research Database (Denmark)

    Oddershede, Niels; Gran, Fredrik; Jensen, Jørgen Arendt

    2007-01-01

    Ultrasonic color flow maps are made by estimating the velocities line by line over the region of interest. For each velocity estimate, multiple repetitions are needed. This sets a limit on the frame rate, which becomes increasingly severe when imaging deeper lying structures or when simultaneously...... acquiring spectrogram data for triplex imaging. This paper proposes a method for decreasing the data acquisition time by simultaneously sampling multiple lines at different spatial positions for the color flow map using narrow band signals with disjoint spectral support. The signals are separated...... in the receiver by filters matched to the emitted waveforms and the autocorrelation estimator is applied. Alternatively, one spectral band can be used for creating a color flow map, while data for a number of spectrograms are acquired simultaneously. Using three disjoint spectral bands, this will result...

  5. Rapid 'on-line' image processing as a tool in the evaluation of kinetic and morphological aspects of receptor-induced cell activation.

    Science.gov (United States)

    Theler, J M; Wollheim, C B; Schlegel, W

    1991-01-01

    Transmembrane signalling involves rapid and spatially well defined changes in cytosolic free Ca2+, [Ca2+]i. Specific technologies involving image processing permit the analysis of kinetic and morphological aspects of [Ca2+]i at the subcellular level with the fluorescent Ca2+ probe fura-2. Fluorescence excitation wavelengths (340 nm or 380 nm) are alternated in synchrony with the acquisition at video rate of images captured with an intensified CCD camera. Images are digitized, recursively filtered, divided, and displayed after calibration of the 'ratio' image into a numerical [Ca2+]i scale. The image processor IMAGINE (Synoptics Ltd., UK) permits these operations at video rate. This produces 'on-line' [Ca2+]i images in real time which are stored on video tapes for subsequent analysis. The present communication summarizes the rationale for the selection of our current technologies. A comparison with alternative solutions should highlight the particular advantages and drawbacks of our approach. The present text thus should serve as a help for investigators who try to assemble image processing tools for work in the receptor and cellular signalling field.

  6. Rapid visuomotor processing of phobic images in spider- and snake-fearful participants.

    Science.gov (United States)

    Haberkamp, Anke; Schmidt, Filipp; Schmidt, Thomas

    2013-10-01

    This study investigates enhanced visuomotor processing of phobic compared to fear-relevant and neutral stimuli. We used a response priming design to measure rapid, automatic motor activation by natural images (spiders, snakes, mushrooms, and flowers) in spider-fearful, snake-fearful, and control participants. We found strong priming effects in all tasks and conditions; however, results showed marked differences between groups. Most importantly, in the group of spider-fearful individuals, spider pictures had a strong and specific influence on even the fastest motor responses: Phobic primes entailed the largest priming effects, and phobic targets accelerated responses, both effects indicating speeded response activation by phobic images. In snake-fearful participants, this processing enhancement for phobic material was less pronounced and extended to both snake and spider images. We conclude that spider phobia leads to enhanced processing capacity for phobic images. We argue that this is enabled by long-term perceptual learning processes. © 2013.

  7. Rapid mapping of digital integrated circuit logic gates via multi-spectral backside imaging

    CERN Document Server

    Adato, Ronen; Zangeneh, Mahmoud; Zhou, Boyou; Joshi, Ajay; Goldberg, Bennett; Unlu, M Selim

    2016-01-01

    Modern semiconductor integrated circuits are increasingly fabricated at untrusted third party foundries. There now exist myriad security threats of malicious tampering at the hardware level and hence a clear and pressing need for new tools that enable rapid, robust and low-cost validation of circuit layouts. Optical backside imaging offers an attractive platform, but its limited resolution and throughput cannot cope with the nanoscale sizes of modern circuitry and the need to image over a large area. We propose and demonstrate a multi-spectral imaging approach to overcome these obstacles by identifying key circuit elements on the basis of their spectral response. This obviates the need to directly image the nanoscale components that define them, thereby relaxing resolution and spatial sampling requirements by 1 and 2 - 4 orders of magnitude respectively. Our results directly address critical security needs in the integrated circuit supply chain and highlight the potential of spectroscopic techniques to addres...

  8. MSCT versus CBCT: evaluation of high-resolution acquisition modes for dento-maxillary and skull-base imaging

    Energy Technology Data Exchange (ETDEWEB)

    Dillenseger, Jean-Philippe; Goetz, Christian [Hopitaux Universitaires de Strasbourg, Imagerie Preclinique-UF6237, Pole d' imagerie, Strasbourg (France); Universite de Strasbourg, Icube, equipe MMB, CNRS, Strasbourg (France); Universite de Strasbourg, Federation de Medecine Translationnelle de Strasbourg, Faculte de Medecine, Strasbourg (France); Matern, Jean-Francois [Hopitaux Universitaires de Strasbourg, Imagerie Preclinique-UF6237, Pole d' imagerie, Strasbourg (France); Universite de Strasbourg, Federation de Medecine Translationnelle de Strasbourg, Faculte de Medecine, Strasbourg (France); Gros, Catherine-Isabelle; Bornert, Fabien [Universite de Strasbourg, Federation de Medecine Translationnelle de Strasbourg, Faculte de Medecine, Strasbourg (France); Universite de Strasbourg, Faculte de Chirurgie Dentaire, Strasbourg (France); Le Minor, Jean-Marie [Universite de Strasbourg, Icube, equipe MMB, CNRS, Strasbourg (France); Universite de Strasbourg, Federation de Medecine Translationnelle de Strasbourg, Faculte de Medecine, Strasbourg (France); Universite de Strasbourg, Institut d' Anatomie Normale, Strasbourg (France); Constantinesco, Andre [Hopitaux Universitaires de Strasbourg, Imagerie Preclinique-UF6237, Pole d' imagerie, Strasbourg (France); Choquet, Philippe [Hopitaux Universitaires de Strasbourg, Imagerie Preclinique-UF6237, Pole d' imagerie, Strasbourg (France); Universite de Strasbourg, Icube, equipe MMB, CNRS, Strasbourg (France); Universite de Strasbourg, Federation de Medecine Translationnelle de Strasbourg, Faculte de Medecine, Strasbourg (France); Hopital de Hautepierre, Imagerie Preclinique, Biophysique et Medecine Nucleaire, Strasbourg Cedex (France)

    2014-09-24

    Our aim was to conduct a quantitative and qualitative evaluation of high-resolution skull-bone imaging for dentistry and otolaryngology using different architectures of recent X-ray computed tomography systems. Three multi-slice computed tomography (MSCT) systems and one Cone-beam computed tomography (CBCT) system were used in this study. All apparatuses were tested with installed acquisition modes and proprietary reconstruction software enabling high-resolution bone imaging. Quantitative analyses were performed with small fields of view with the preclinical vmCT phantom, which permits to measure spatial resolution, geometrical accuracy, linearity and homogeneity. Ten operators performed visual qualitative analyses on the vmCT phantom images, and on dry human skull images. Quantitative analysis showed no significant differences between protocols in terms of linearity and geometric accuracy. All MSCT systems present a better homogeneity than the CBCT. Both quantitative and visual analyses demonstrate that CBCT acquisitions are not better than the collimated helical MSCT mode. Our results demonstrate that current high-resolution MSCT protocols could exceed the performance of a previous generation CBCT system for spatial resolution and image homogeneity. (orig.)

  9. Split-screen display system and standardized methods for ultrasound image acquisition and multi-frame data processing

    Science.gov (United States)

    Selzer, Robert H. (Inventor); Hodis, Howard N. (Inventor)

    2011-01-01

    A standardized acquisition methodology assists operators to accurately replicate high resolution B-mode ultrasound images obtained over several spaced-apart examinations utilizing a split-screen display in which the arterial ultrasound image from an earlier examination is displayed on one side of the screen while a real-time "live" ultrasound image from a current examination is displayed next to the earlier image on the opposite side of the screen. By viewing both images, whether simultaneously or alternately, while manually adjusting the ultrasound transducer, an operator is able to bring into view the real-time image that best matches a selected image from the earlier ultrasound examination. Utilizing this methodology, dynamic material properties of arterial structures, such as IMT and diameter, are measured in a standard region over successive image frames. Each frame of the sequence has its echo edge boundaries automatically determined by using the immediately prior frame's true echo edge coordinates as initial boundary conditions. Computerized echo edge recognition and tracking over multiple successive image frames enhances measurement of arterial diameter and IMT and allows for improved vascular dimension measurements, including vascular stiffness and IMT determinations.

  10. A rapid method for creating qualitative images indicative of thick oil emulsion on the ocean's surface from imaging spectrometer data

    Science.gov (United States)

    Kokaly, Raymond F.; Hoefen, Todd M.; Livo, K. Eric; Swayze, Gregg A.; Leifer, Ira; McCubbin, Ian B.; Eastwood, Michael L.; Green, Robert O.; Lundeen, Sarah R.; Sarture, Charles M.; Steele, Denis; Ryan, Thomas; Bradley, Eliza S.; Roberts, Dar A.; ,

    2010-01-01

    This report describes a method to create color-composite images indicative of thick oil:water emulsions on the surface of clear, deep ocean water by using normalized difference ratios derived from remotely sensed data collected by an imaging spectrometer. The spectral bands used in the normalized difference ratios are located in wavelength regions where the spectra of thick oil:water emulsions on the ocean's surface have a distinct shape compared to clear water and clouds. In contrast to quantitative analyses, which require rigorous conversion to reflectance, the method described is easily computed and can be applied rapidly to radiance data or data that have been atmospherically corrected or ground-calibrated to reflectance. Examples are shown of the method applied to Airborne Visible/Infrared Imaging Spectrometer data collected May 17 and May 19, 2010, over the oil spill from the Deepwater Horizon offshore oil drilling platform in the Gulf of Mexico.

  11. Novel Applications of Rapid Prototyping in Gamma-ray and X-ray Imaging

    Science.gov (United States)

    Miller, Brian W.; Moore, Jared W.; Gehm, Michael E.; Furenlid, Lars R.; Barrett, Harrison H.

    2010-01-01

    Advances in 3D rapid-prototyping printers, 3D modeling software, and casting techniques allow for the fabrication of cost-effective, custom components in gamma-ray and x-ray imaging systems. Applications extend to new fabrication methods for custom collimators, pinholes, calibration and resolution phantoms, mounting and shielding components, and imaging apertures. Details of the fabrication process for these components are presented, specifically the 3D printing process, cold casting with a tungsten epoxy, and lost-wax casting in platinum. PMID:22984341

  12. A rapid method for counting nucleated erythrocytes on stained blood smears by digital image analysis

    Science.gov (United States)

    Gering, E.; Atkinson, C.T.

    2004-01-01

    Measures of parasitemia by intraerythrocytic hematozoan parasites are normally expressed as the number of infected erythrocytes per n erythrocytes and are notoriously tedious and time consuming to measure. We describe a protocol for generating rapid counts of nucleated erythrocytes from digital micrographs of thin blood smears that can be used to estimate intensity of hematozoan infections in nonmammalian vertebrate hosts. This method takes advantage of the bold contrast and relatively uniform size and morphology of erythrocyte nuclei on Giemsa-stained blood smears and uses ImageJ, a java-based image analysis program developed at the U.S. National Institutes of Health and available on the internet, to recognize and count these nuclei. This technique makes feasible rapid and accurate counts of total erythrocytes in large numbers of microscope fields, which can be used in the calculation of peripheral parasitemias in low-intensity infections.

  13. In vivo testing of a prototype system providing simultaneous white light and near infrared autofluorescence image acquisition for detection of bladder cancer

    Science.gov (United States)

    Jacobson, Michael C.; deVere White, Ralph; Demos, Stavros G.

    2012-03-01

    A prototype instrument developed to provide simultaneously ordinary visual endoscopy together with near infrared (NIR) autofluorescence imaging via parallel image acquisition is demonstrated. The two images are recorded concurrently and the instrument interfaces with any ordinary endoscope. Preliminary results of a pilot study focused on imaging of bladder tumors in vivo using this instrumentation are presented. The experimental results demonstrate the capabilities of this instrumentation design, imaging methodology, and define the current limitation for further development of the system.

  14. Sampling Number Effects in 2D and Range Imaging of Range-gated Acquisition

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Seong-Ouk; Park, Seung-Kyu; Baik, Sung-Hoon; Cho, Jai-Wan; Jeong, Kyung-Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this paper, we analyzed the number effects of sampling images for making a 2D image and a range image from acquired RGI images. We analyzed the number effects of RGI images for making a 2D image and a range image using a RGI vision system. As the results, 2D image quality was not much depended on the number of sampling images but on how much well extract efficient RGI images. But, the number of RGI images was important for making a range image because range image quality was proportional to the number of RGI images. Image acquiring in a monitoring area of nuclear industry is an important function for safety inspection and preparing appropriate control plans. To overcome the non-visualization problem caused by airborne obstacle particles, vision systems should have extra-functions, such as active illumination lightening through disturbance airborne particles. One of these powerful active vision systems is a range-gated imaging system. The vision system based on the range-gated imaging system can acquire image data from raining or smoking environments. Range-gated imaging (RGI) is a direct active visualization technique using a highly sensitive image sensor and a high intensity illuminant. Currently, the range-gated imaging technique providing 2D and 3D images is one of emerging active vision technologies. The range-gated imaging system gets vision information by summing time sliced vision images. In the RGI system, a high intensity illuminant illuminates for ultra-short time and a highly sensitive image sensor is gated by ultra-short exposure time to only get the illumination light. Here, the illuminant illuminates objects by flashing strong light through airborne disturbance particles. Thus, in contrast to passive conventional vision systems, the RGI active vision technology robust for low-visibility environments.

  15. Development of an acquisition protocol and a segmentation algortihm for wounds of cutaneous Leishmaniasis in digital images

    Science.gov (United States)

    Diaz, Kristians; Castañeda, Benjamín; Miranda, César; Lavarello, Roberto; Llanos, Alejandro

    2010-03-01

    We developed a protocol for the acquisition of digital images and an algorithm for a color-based automatic segmentation of cutaneous lesions of Leishmaniasis. The protocol for image acquisition provides control over the working environment to manipulate brightness, lighting and undesirable shadows on the injury using indirect lighting. Also, this protocol was used to accurately calculate the area of the lesion expressed in mm2 even in curved surfaces by combining the information from two consecutive images. Different color spaces were analyzed and compared using ROC curves in order to determine the color layer with the highest contrast between the background and the wound. The proposed algorithm is composed of three stages: (1) Location of the wound determined by threshold and mathematical morphology techniques to the H layer of the HSV color space, (2) Determination of the boundaries of the wound by analyzing the color characteristics in the YIQ space based on masks (for the wound and the background) estimated from the first stage, and (3) Refinement of the calculations obtained on the previous stages by using the discrete dynamic contours algorithm. The segmented regions obtained with the algorithm were compared with manual segmentations made by a medical specialist. Broadly speaking, our results support that color provides useful information during segmentation and measurement of wounds of cutaneous Leishmaniasis. Results from ten images showed 99% specificity, 89% sensitivity, and 98% accuracy.

  16. Optimizing Uas Image Acquisition and Geo-Registration for Precision Agriculture

    Science.gov (United States)

    Hearst, A. A.; Cherkauer, K. A.; Rainey, K. M.

    2014-12-01

    Unmanned Aircraft Systems (UASs) can acquire imagery of crop fields in various spectral bands, including the visible, near-infrared, and thermal portions of the spectrum. By combining techniques of computer vision, photogrammetry, and remote sensing, these images can be stitched into precise, geo-registered maps, which may have applications in precision agriculture and other industries. However, the utility of these maps will depend on their positional accuracy. Therefore, it is important to quantify positional accuracy and consider the tradeoffs between accuracy, field site setup, and the computational requirements for data processing and analysis. This will enable planning of data acquisition and processing to obtain the required accuracy for a given project. This study focuses on developing and evaluating methods for geo-registration of raw aerial frame photos acquired by a small fixed-wing UAS. This includes visual, multispectral, and thermal imagery at 3, 6, and 14 cm/pix resolutions, respectively. The study area is 10 hectares of soybean fields at the Agronomy Center for Research and Education (ACRE) at Purdue University. The dataset consists of imagery from 6 separate days of flights (surveys) and supporting ground measurements. The Direct Sensor Orientation (DiSO) and Integrated Sensor Orientation (InSO) methods for geo-registration are tested using 16 Ground Control Points (GCPs). Subsets of these GCPs are used to test for the effects of different numbers and spatial configurations of GCPs on positional accuracy. The horizontal and vertical Root Mean Squared Error (RMSE) is used as the primary metric of positional accuracy. Preliminary results from 1 of the 6 surveys show that the DiSO method (0 GCPs used) achieved an RMSE in the X, Y, and Z direction of 2.46 m, 1.04 m, and 1.91 m, respectively. InSO using 5 GCPs achieved an RMSE of 0.17 m, 0.13 m, and 0.44 m. InSO using 10 GCPs achieved an RMSE of 0.10 m, 0.09 m, and 0.12 m. Further analysis will identify

  17. A set of 400 pictures standardized for French: norms for name agreement, image agreement, familiarity, visual complexity, image variability, and age of acquisition.

    Science.gov (United States)

    Alario, F X; Ferrand, L

    1999-08-01

    The present article provides French normative measures for 400 line drawings taken from Cycowicz, Friedman, Rothstein, and Snodgrass (1997), including the 260 line drawings that were normed by Snodgrass and Vanderwart (1980). The pictures have been standardized on the following variables: name agreement, image agreement, familiarity, visual complexity, image variability, and age of acquisition. These normative data also include word frequency values and the first verbal associate (taken from Ferrand & Alario, 1998). The six variables obtained are important because of their potential effect in many fields of psychology, especially the study of cognitive processes such as visual perception, language, and memory.

  18. AUTOMATED FORMOSAT IMAGE PROCESSING SYSTEM FOR RAPID RESPONSE TO INTERNATIONAL DISASTERS

    Directory of Open Access Journals (Sweden)

    M. C. Cheng

    2016-06-01

    Full Text Available FORMOSAT-2, Taiwan’s first remote sensing satellite, was successfully launched in May of 2004 into the Sun-synchronous orbit at 891 kilometers of altitude. With the daily revisit feature, the 2-m panchromatic, 8-m multi-spectral resolution images captured have been used for researches and operations in various societal benefit areas. This paper details the orchestration of various tasks conducted in different institutions in Taiwan in the efforts responding to international disasters. The institutes involved including its space agency-National Space Organization (NSPO, Center for Satellite Remote Sensing Research of National Central University, GIS Center of Feng-Chia University, and the National Center for High-performance Computing. Since each institution has its own mandate, the coordinated tasks ranged from receiving emergency observation requests, scheduling and tasking of satellite operation, downlink to ground stations, images processing including data injection, ortho-rectification, to delivery of image products. With the lessons learned from working with international partners, the FORMOSAT Image Processing System has been extensively automated and streamlined with a goal to shorten the time between request and delivery in an efficient manner. The integrated team has developed an Application Interface to its system platform that provides functions of search in archive catalogue, request of data services, mission planning, inquiry of services status, and image download. This automated system enables timely image acquisition and substantially increases the value of data product. Example outcome of these efforts in recent response to support Sentinel Asia in Nepal Earthquake is demonstrated herein.

  19. Hyperspectral Imaging as a Rapid Quality Control Method for Herbal Tea Blends

    Directory of Open Access Journals (Sweden)

    Majolie Djokam

    2017-03-01

    Full Text Available In South Africa, indigenous herbal teas are enjoyed due to their distinct taste and aroma. The acclaimed health benefits of herbal teas include the management of chronic diseases such as hypertension and diabetes. Quality control of herbal teas has become important due to the availability of different brands of varying quality and the production of tea blends. The potential of hyperspectral imaging as a rapid quality control method for herbal tea blends from rooibos (Aspalathus linearis, honeybush (Cyclopia intermedia, buchu (Agathosma Betulina and cancerbush (Sutherlandia frutescens was investigated. Hyperspectral images of raw materials and intact tea bags were acquired using a sisuChema shortwave infrared (SWIR hyperspectral pushbroom imaging system (920–2514 nm. Principal component analysis (PCA plots showed clear discrimination between raw materials. Partial least squares discriminant analysis (PLS-DA models correctly predicted the raw material constituents of each blend and accurately determined the relative proportions. The results were corroborated independently using ultra-high performance liquid chromatography coupled to mass spectrometry (UHPLC-MS. This study demonstrated the application of hyperspectral imaging coupled with chemometric modelling as a reliable, rapid and non-destructive quality control method for authenticating herbal tea blends and to determine relative proportions in a tea bag.

  20. Data of NODDI diffusion metrics in the brain and computer simulation of hybrid diffusion imaging (HYDI acquisition scheme

    Directory of Open Access Journals (Sweden)

    Chandana Kodiweera

    2016-06-01

    Full Text Available This article provides NODDI diffusion metrics in the brains of 52 healthy participants and computer simulation data to support compatibility of hybrid diffusion imaging (HYDI, “Hybrid diffusion imaging” [1] acquisition scheme in fitting neurite orientation dispersion and density imaging (NODDI model, “NODDI: practical in vivo neurite orientation dispersion and density imaging of the human brain” [2]. HYDI is an extremely versatile diffusion magnetic resonance imaging (dMRI technique that enables various analyzes methods using a single diffusion dataset. One of the diffusion data analysis methods is the NODDI computation, which models the brain tissue with three compartments: fast isotropic diffusion (e.g., cerebrospinal fluid, anisotropic hindered diffusion (e.g., extracellular space, and anisotropic restricted diffusion (e.g., intracellular space. The NODDI model produces microstructural metrics in the developing brain, aging brain or human brain with neurologic disorders. The first dataset provided here are the means and standard deviations of NODDI metrics in 48 white matter region-of-interest (ROI averaging across 52 healthy participants. The second dataset provided here is the computer simulation with initial conditions guided by the first dataset as inputs and gold standard for model fitting. The computer simulation data provide a direct comparison of NODDI indices computed from the HYDI acquisition [1] to the NODDI indices computed from the originally proposed acquisition [2]. These data are related to the accompanying research article “Age Effects and Sex Differences in Human Brain White Matter of Young to Middle-Aged Adults: A DTI, NODDI, and q-Space Study” [3].

  1. The method of parallel-hierarchical transformation for rapid recognition of dynamic images using GPGPU technology

    Science.gov (United States)

    Timchenko, Leonid; Yarovyi, Andrii; Kokriatskaya, Nataliya; Nakonechna, Svitlana; Abramenko, Ludmila; Ławicki, Tomasz; Popiel, Piotr; Yesmakhanova, Laura

    2016-09-01

    The paper presents a method of parallel-hierarchical transformations for rapid recognition of dynamic images using GPU technology. Direct parallel-hierarchical transformations based on cluster CPU-and GPU-oriented hardware platform. Mathematic models of training of the parallel hierarchical (PH) network for the transformation are developed, as well as a training method of the PH network for recognition of dynamic images. This research is most topical for problems on organizing high-performance computations of super large arrays of information designed to implement multi-stage sensing and processing as well as compaction and recognition of data in the informational structures and computer devices. This method has such advantages as high performance through the use of recent advances in parallelization, possibility to work with images of ultra dimension, ease of scaling in case of changing the number of nodes in the cluster, auto scan of local network to detect compute nodes.

  2. Diagnostic Phase of Calcium Scoring Scan Applied as the Center of Acquisition Window of Coronary Computed Tomography Angiography Improves Image Quality in Minimal Acquisition Window Scan (Target CTA Mode Using the Second Generation 320-Row CT

    Directory of Open Access Journals (Sweden)

    Eriko Maeda

    2016-01-01

    Full Text Available Objective. To compare the image quality of coronary computed tomography angiography (CCTA acquired under two conditions: 75% fixed as the acquisition window center (Group 75% and the diagnostic phase for calcium scoring scan as the center (CS; Group CS. Methods. 320-row cardiac CT with a minimal acquisition window (scanned using “Target CTA” mode was performed on 81 patients. In Group 75% (n = 40, CS was obtained and reconstructed at 75% and the center of the CCTA acquisition window was set at 75%. In Group CS (n = 41, CS was obtained at 75% and the diagnostic phase showing minimal artifacts was applied as the center of the CCTA acquisition window. Image quality was evaluated using a four-point scale (4-excellent and the mean scores were compared between groups. Results. The CCTA scan diagnostic phase occurred significantly earlier in CS (75.7 ± 3.2% vs. 73.6 ± 4.5% for Groups 75% and CS, resp., p = 0.013. The mean Group CS image quality score (3.58 ± 0.63 was also higher than that for Group 75% (3.19 ± 0.66, p < 0.0001. Conclusions. The image quality of CCTA in Target CTA mode was significantly better when the center of acquisition window is adjusted using CS.

  3. ReagentTF: a rapid and versatile optical clearing method for biological imaging(Conference Presentation)

    Science.gov (United States)

    Yu, Tingting; Zhu, Jingtan; Li, Yusha; Qi, Yisong; Xu, Jianyi; Gong, Hui; Luo, Qingming; Zhu, Dan

    2017-02-01

    The emergence of various optical clearing methods provides a great potential for imaging deep inside tissues by combining with multiple-labelling and microscopic imaging techniques. They were generally developed for specific imaging demand thus presented some non-negligible limitations such as long incubation time, tissue deformation, fluorescence quenching, incompatibility with immunostaining or lipophilic tracers. In this study, we developed a rapid and versatile clearing method, termed ReagentTF, for deep imaging of various fluorescent samples. This method can not only efficiently clear embryos, neonatal whole-brains and adult thick brain sections by simple immersion in aqueous mixtures with minimal volume change, but also can preserve fluorescence of various fluorescent proteins and simultaneously be compatible with immunostaining and lipophilic neuronal dyes. We demonstrate the effectiveness of this method in reconstructing the cell distributions of mouse hippocampus, visualizing the neural projection from CA1 (Cornu Ammonis 1) to HDB (nucleus of the horizontal limb of the diagonal band), and observing the growth of forelimb plexus in whole-mount embryos. These results suggest that ReagentTF is useful for large-volume imaging and will be an option for the deep imaging of biological tissues.

  4. Rapid Texture Optimization of Three-Dimensional Urban Model Based on Oblique Images.

    Science.gov (United States)

    Zhang, Weilong; Li, Ming; Guo, Bingxuan; Li, Deren; Guo, Ge

    2017-04-20

    Seamless texture mapping is one of the key technologies for photorealistic 3D texture reconstruction. In this paper, a method of rapid texture optimization of 3D urban reconstruction based on oblique images is proposed aiming at the existence of texture fragments, seams, and inconsistency of color in urban 3D texture mapping based on low-altitude oblique images. First, we explore implementing radiation correction on the experimental images with a radiation procession algorithm. Then, an efficient occlusion detection algorithm based on OpenGL is proposed according to the mapping relation between the terrain triangular mesh surface and the images to implement the occlusion detection of the visible texture on the triangular facets as well as create a list of visible images. Finally, a texture clustering algorithm is put forward based on Markov Random Field utilizing the inherent attributes of the images and solve the energy function minimization by Graph-Cuts. The experimental results display that the method is capable of decreasing the existence of texture fragments, seams, and inconsistency of color in the 3D texture model reconstruction.

  5. SPLASSH: Open source software for camera-based high-speed, multispectral in-vivo optical image acquisition.

    Science.gov (United States)

    Sun, Ryan; Bouchard, Matthew B; Hillman, Elizabeth M C

    2010-08-02

    Camera-based in-vivo optical imaging can provide detailed images of living tissue that reveal structure, function, and disease. High-speed, high resolution imaging can reveal dynamic events such as changes in blood flow and responses to stimulation. Despite these benefits, commercially available scientific cameras rarely include software that is suitable for in-vivo imaging applications, making this highly versatile form of optical imaging challenging and time-consuming to implement. To address this issue, we have developed a novel, open-source software package to control high-speed, multispectral optical imaging systems. The software integrates a number of modular functions through a custom graphical user interface (GUI) and provides extensive control over a wide range of inexpensive IEEE 1394 Firewire cameras. Multispectral illumination can be incorporated through the use of off-the-shelf light emitting diodes which the software synchronizes to image acquisition via a programmed microcontroller, allowing arbitrary high-speed illumination sequences. The complete software suite is available for free download. Here we describe the software's framework and provide details to guide users with development of this and similar software.

  6. Revisiting Age-of-Acquisition Effects in Spanish Visual Word Recognition: The Role of Item Imageability

    Science.gov (United States)

    Wilson, Maximiliano A.; Cuetos, Fernando; Davies, Rob; Burani, Cristina

    2013-01-01

    Word age-of-acquisition (AoA) affects reading. The mapping hypothesis predicts AoA effects when input--output mappings are arbitrary. In Spanish, the orthography-to-phonology mappings required for word naming are consistent; therefore, no AoA effects are expected. Nevertheless, AoA effects have been found, motivating the present investigation of…

  7. Motor-symptom laterality affects acquisition in Parkinson's disease: A cognitive and functional magnetic resonance imaging study.

    Science.gov (United States)

    Huang, Pei; Tan, Yu-Yan; Liu, Dong-Qiang; Herzallah, Mohammad M; Lapidow, Elizabeth; Wang, Ying; Zang, Yu-Feng; Gluck, Mark A; Chen, Sheng-Di

    2017-07-01

    Asymmetric onset of motor symptoms in PD can affect cognitive function. We examined whether motor-symptom laterality could affect feedback-based associative learning and explored its underlying neural mechanism by functional magnetic resonance imaging in PD patients. We recruited 63 early-stage medication-naïve PD patients (29 left-onset medication-naïve patients, 34 right-onset medication-naïve patients) and 38 matched normal controls. Subjects completed an acquired equivalence task (including acquisition, retention, and generalization) and resting-state functional magnetic resonance imaging scans. Learning accuracy and response time in each phase of the task were recorded for behavioral measures. Regional homogeneity was used to analyze resting-state functional magnetic resonance imaging data, with regional homogeneity lateralization to evaluate hemispheric functional asymmetry in the striatum. Left-onset patients made significantly more errors in acquisition (feedback-based associative learning) than right-onset patients and normal controls, whereas right-onset patients performed as well as normal controls. There was no significant difference among these three groups in the accuracy of either retention or generalization phase. The three groups did not show significant differences in response time. In the left-onset group, there was an inverse relationship between acquisition errors and regional homogeneity in the right dorsal rostral putamen. There were no significant regional homogeneity changes in either the left or the right dorsal rostral putamen in right-onset patients when compared to controls. Motor-symptom laterality could affect feedback-based associative learning in PD, with left-onset medication-naïve patients being selectively impaired. Dysfunction in the right dorsal rostral putamen may underlie the observed deficit in associative learning in patients with left-sided onset.© 2016 International Parkinson and Movement Disorder Society. © 2017

  8. High performance image acquisition and processing architecture for fast plant system controllers based on FPGA and GPU

    Energy Technology Data Exchange (ETDEWEB)

    Nieto, J., E-mail: jnieto@sec.upm.es [Grupo de Investigación en Instrumentación y Acústica Aplicada, Universidad Politécnica de Madrid, Crta. Valencia Km-7, Madrid 28031 (Spain); Sanz, D.; Guillén, P.; Esquembri, S.; Arcas, G. de; Ruiz, M. [Grupo de Investigación en Instrumentación y Acústica Aplicada, Universidad Politécnica de Madrid, Crta. Valencia Km-7, Madrid 28031 (Spain); Vega, J.; Castro, R. [Asociación EURATOM/CIEMAT para Fusión, Madrid (Spain)

    2016-11-15

    Highlights: • To test an image acquisition and processing system for Camera Link devices based in a FPGA, compliant with ITER fast controllers. • To move data acquired from the set NI1483-NIPXIe7966R directly to a NVIDIA GPU using NVIDIA GPUDirect RDMA technology. • To obtain a methodology to include GPUs processing in ITER Fast Plant Controllers, using EPICS integration through Nominal Device Support (NDS). - Abstract: The two dominant technologies that are being used in real time image processing are Field Programmable Gate Array (FPGA) and Graphical Processor Unit (GPU) due to their algorithm parallelization capabilities. But not much work has been done to standardize how these technologies can be integrated in data acquisition systems, where control and supervisory requirements are in place, such as ITER (International Thermonuclear Experimental Reactor). This work proposes an architecture, and a development methodology, to develop image acquisition and processing systems based on FPGAs and GPUs compliant with ITER fast controller solutions. A use case based on a Camera Link device connected to an FPGA DAQ device (National Instruments FlexRIO technology), and a NVIDIA Tesla GPU series card has been developed and tested. The architecture proposed has been designed to optimize system performance by minimizing data transfer operations and CPU intervention thanks to the use of NVIDIA GPUDirect RDMA and DMA technologies. This allows moving the data directly between the different hardware elements (FPGA DAQ-GPU-CPU) avoiding CPU intervention and therefore the use of intermediate CPU memory buffers. A special effort has been put to provide a development methodology that, maintaining the highest possible abstraction from the low level implementation details, allows obtaining solutions that conform to CODAC Core System standards by providing EPICS and Nominal Device Support.

  9. Image acquisition and interpretation criteria for {sup 99m}Tc-HMPAO-labelled white blood cell scintigraphy: results of a multicentre study

    Energy Technology Data Exchange (ETDEWEB)

    Erba, Paola A. [University of Pisa Medical School (Italy). Regional Center of Nuclear Medicine; Glaudemans, Andor W.J.M.; Dierckx, Rudi A.J.O. [University Medical Center Groningen (Netherlands). Dept. of Nuclear Medicine and Molecular Imaging; Veltman, Niels C. [Jeroen Bosch Hospital, ' s-Hertogenbosch (Netherlands). Dept. of Nuclear Medicine; Sollini, Martina [Arcisprdale S. Maria Nuova - IRCCS, Reggio Emilia (Italy). Nuclear Medicine Unit; Pacilio, Marta; Galli, Filippo [Sapienza Univ., Rome (Italy). Nuclear Medicine Unit; Signore, Alberto [University Medical Center Groningen (Netherlands). Dept. of Nuclear Medicine and Molecular Imaging; Sapienza Univ., Rome (Italy). Nuclear Medicine Unit; Sapienza Univ., Rome (Italy). Ospedale S. Andrea Medicina Nucleare

    2014-04-15

    There is no consensus yet on the best protocol for planar image acquisition and interpretation of radiolabelled white blood cell (WBC) scintigraphy. This may account for differences in reported diagnostic accuracy amongst different centres. This was a multicentre retrospective study analysing 235 WBC scans divided into two groups. The first group of scans (105 patients) were acquired with a fixed-time acquisition protocol and the second group (130 patients) were acquired with a decay time-corrected acquisition protocol. Planar images were interpreted both qualitatively and semiquantitatively. Three blinded readers analysed the images. The most accurate imaging acquisition protocol comprised image acquisition at 3 - 4 h and at 20 - 24 h in time mode with acquisition times corrected for isotope decay. Using this protocol, visual analysis had high sensitivity and specificity in the diagnosis of infection. Semiquantitative analysis could be used in doubtful cases, with no cut-off for the percentage increase in radiolabelled WBC over time, as a criterion to define a positive scan. (orig.)

  10. Multimodal imaging documentation of rapid evolution of retinal changes in handheld laser-induced maculopathy.

    Science.gov (United States)

    Dhrami-Gavazi, Elona; Lee, Winston; Balaratnasingam, Chandrakumar; Kayserman, Larisa; Yannuzzi, Lawrence A; Freund, K Bailey

    2015-01-01

    To use multimodal imaging to document the relatively rapid clinical evolution of handheld laser-induced maculopathy (HLIM). To demonstrate that inadvertent ocular injury can result from devices mislabeled with respect to their power specifications. The clinical course of a 17-year-old male who sustained self-inflicted, central macular damage from a 20-25 s direct stare at a red-spectrum, handheld laser pointer ordered from an internet retailer is provided. Retrospective review of multimodal imaging that includes fundus photography, fluorescein angiography, MultiColor reflectance, eye-tracked spectral domain optical coherence tomography (SD-OCT), fundus autofluorescence, and microperimetry is used to describe the evolving clinical manifestations of HLIM in the first 3 months. Curvilinear bands of dense hyperreflectivity extending from the outer retina and following the Henle fibers were seen on SD-OCT immediately after injury. This characteristic appearance had largely resolved by 2 weeks. There was significant non-uniformity in the morphological characteristics of HLIM lesions between autofluorescence and reflectance images. The pattern of lesion evolution was also significantly different between imaging modalities. Analysis of the laser device showed its wavelength to be correctly listed, but the power was found to be 102.5-105 mW, as opposed to the laser -induced maculopathy, this finding can undergo rapid resolution in the span of several days. In the absence of this finding, other multimodal imaging clues and a careful history may aid in recognizing this diagnosis. A greater awareness regarding inaccurate labeling on some of these devices could help reduce the frequency of this preventable entity.

  11. Brain activity-based image classification from rapid serial visual presentation.

    Science.gov (United States)

    Bigdely-Shamlo, Nima; Vankov, Andrey; Ramirez, Rey R; Makeig, Scott

    2008-10-01

    We report the design and performance of a brain-computer interface (BCI) system for real-time single-trial binary classification of viewed images based on participant-specific dynamic brain response signatures in high-density (128-channel) electroencephalographic (EEG) data acquired during a rapid serial visual presentation (RSVP) task. Image clips were selected from a broad area image and presented in rapid succession (12/s) in 4.1-s bursts. Participants indicated by subsequent button press whether or not each burst of images included a target airplane feature. Image clip creation and search path selection were designed to maximize user comfort and maintain user awareness of spatial context. Independent component analysis (ICA) was used to extract a set of independent source time-courses and their minimally-redundant low-dimensional informative features in the time and time-frequency amplitude domains from 128-channel EEG data recorded during clip burst presentations in a training session. The naive Bayes fusion of two Fisher discriminant classifiers, computed from the 100 most discriminative time and time-frequency features, respectively, was used to estimate the likelihood that each clip contained a target feature. This estimator was applied online in a subsequent test session. Across eight training/test session pairs from seven participants, median area under the receiver operator characteristic curve, by tenfold cross validation, was 0.97 for within-session and 0.87 for between-session estimates, and was nearly as high (0.83) for targets presented in bursts that participants mistakenly reported to include no target features.

  12. Rapid intracerebroventricular delivery of Cu-DOTA-etanercept after peripheral administration demonstrated by PET imaging

    Directory of Open Access Journals (Sweden)

    Chen Xiaoyuan

    2009-02-01

    Full Text Available Abstract Background The cytokines interleukin-1 and tumor necrosis factor (TNF, and the cytokine blocker interleukin-1 receptor antagonist, all have been demonstrated to enter the cerebrospinal fluid (CSF following peripheral administration. Recent reports of rapid clinical improvement in patients with Alzheimer's disease and related forms of dementia following perispinal administration of etanercept, a TNF antagonist, suggest that etanercept also has the ability to reach the brain CSF. To investigate, etanercept was labeled with a positron emitter to enable visualization of its intracranial distribution following peripheral administration by PET in an animal model. Findings Radiolabeling of etanercept with the PET emitter 64Cu was performed by DOTA (1,4,7,10-tetraazadodecane-N,N',N",N"'-tetraacetic acid conjugation of etanercept, followed by column purification and 64Cu labeling. MicroPET imaging revealed accumulation of 64Cu-DOTA-etanercept within the lateral and third cerebral ventricles within minutes of peripheral perispinal administration in a normal rat anesthesized with isoflurane anesthesia, with concentration within the choroid plexus and into the CSF. Conclusion Synthesis of 64Cu-DOTA-etanercept enabled visualization of its intracranial distribution by microPET imaging. MicroPET imaging documented rapid accumulation of 64Cu-DOTA-etanercept within the choroid plexus and the cerebrospinal fluid within the cerebral ventricles of a living rat after peripheral administration. Further study of the effects of etanercept and TNF at the level of the choroid plexus may yield valuable insights into the pathogenesis of Alzheimer's disease.

  13. The Java Image Science Toolkit (JIST) for Rapid Prototyping and Publishing of Neuroimaging Software

    Science.gov (United States)

    Lucas, Blake C.; Bogovic, John A.; Carass, Aaron; Bazin, Pierre-Louis; Prince, Jerry L.; Pham, Dzung

    2010-01-01

    Non-invasive neuroimaging techniques enable extraordinarily sensitive and specific in vivo study of the structure, functional response and connectivity of biological mechanisms. With these advanced methods comes a heavy reliance on computer-based processing, analysis and interpretation. While the neuroimaging community has produced many excellent academic and commercial tool packages, new tools are often required to interpret new modalities and paradigms. Developing custom tools and ensuring interoperability with existing tools is a significant hurdle. To address these limitations, we present a new framework for algorithm development that implicitly ensures tool interoperability, generates graphical user interfaces, provides advanced batch processing tools, and, most importantly, requires minimal additional programming or computational overhead. Java-based rapid prototyping with this system is an efficient and practical approach to evaluate new algorithms since the proposed system ensures that rapidly constructed prototypes are actually fully-functional processing modules with support for multiple GUI's, a broad range of file formats, and distributed computation. Herein, we demonstrate MRI image processing with the proposed system for cortical surface extraction in large cross-sectional cohorts, provide a system for fully automated diffusion tensor image analysis, and illustrate how the system can be used as a simulation framework for the development of a new image analysis method. The system is released as open source under the Lesser GNU Public License (LGPL) through the Neuroimaging Informatics Tools and Resources Clearinghouse (NITRC). PMID:20077162

  14. Rapid and Quantitative Assessment of Cancer Treatment Response Using In Vivo Bioluminescence Imaging

    Directory of Open Access Journals (Sweden)

    Alnawaz Rehemtulla

    2000-01-01

    Full Text Available Current assessment of orthotopic tumor models in animals utilizes survival as the primary therapeutic end point. In vivo bioluminescence imaging (BLI is a sensitive imaging modality that is rapid and accessible, and may comprise an ideal tool for evaluating antineoplastic therapies [1 ]. Using human tumor cell lines constitutively expressing luciferase, the kinetics of tumor growth and response to therapy have been assessed in intraperitoneal [2], subcutaneous, and intravascular [3] cancer models. However, use of this approach for evaluating orthotopic tumor models has not been demonstrated. In this report, the ability of BLI to noninvasively quantitate the growth and therapeuticinduced cell kill of orthotopic rat brain tumors derived from 9L gliosarcoma cells genetically engineered to stably express firefly luciferase (9LLuc was investigated. Intracerebral tumor burden was monitored over time by quantitation of photon emission and tumor volume using a cryogenically cooled CCD camera and magnetic resonance imaging (MRI, respectively. There was excellent correlation (r=0.91 between detected photons and tumor volume. A quantitative comparison of tumor cell kill determined from serial MRI volume measurements and BLI photon counts following 1,3-bis(2-chloroethyl-1-nitrosourea (BCNU treatment revealed that both imaging modalities yielded statistically similar cell kill values (P=.951. These results provide direct validation of BLI imaging as a powerful and quantitative tool for the assessment of antineoplastic therapies in living animals.

  15. VPI - VIBRATION PATTERN IMAGER: A CONTROL AND DATA ACQUISITION SYSTEM FOR SCANNING LASER VIBROMETERS

    Science.gov (United States)

    Rizzi, S. A.

    1994-01-01

    The Vibration Pattern Imager (VPI) system was designed to control and acquire data from laser vibrometer sensors. The PC computer based system uses a digital signal processing (DSP) board and an analog I/O board to control the sensor and to process the data. The VPI system was originally developed for use with the Ometron VPI Sensor (Ometron Limited, Kelvin House, Worsley Bridge Road, London, SE26 5BX, England), but can be readily adapted to any commercially available sensor which provides an analog output signal and requires analog inputs for control of mirror positioning. VPI's graphical user interface allows the operation of the program to be controlled interactively through keyboard and mouse-selected menu options. The main menu controls all functions for setup, data acquisition, display, file operations, and exiting the program. Two types of data may be acquired with the VPI system: single point or "full field". In the single point mode, time series data is sampled by the A/D converter on the I/O board at a user-defined rate for the selected number of samples. The position of the measuring point, adjusted by mirrors in the sensor, is controlled via a mouse input. In the "full field" mode, the measurement point is moved over a user-selected rectangular area with up to 256 positions in both x and y directions. The time series data is sampled by the A/D converter on the I/O board and converted to a root-mean-square (rms) value by the DSP board. The rms "full field" velocity distribution is then uploaded for display and storage. VPI is written in C language and Texas Instruments' TMS320C30 assembly language for IBM PC series and compatible computers running MS-DOS. The program requires 640K of RAM for execution, and a hard disk with 10Mb or more of disk space is recommended. The program also requires a mouse, a VGA graphics display, a Four Channel analog I/O board (Spectrum Signal Processing, Inc.; Westborough, MA), a break-out box and a Spirit-30 board (Sonitech

  16. Rapid susceptibility testing and microcolony analysis of Candida spp. cultured and imaged on porous aluminum oxide.

    Science.gov (United States)

    Ingham, Colin J; Boonstra, Sjoukje; Levels, Suzanne; de Lange, Marit; Meis, Jacques F; Schneeberger, Peter M

    2012-01-01

    Acquired resistance to antifungal agents now supports the introduction of susceptibility testing for species-drug combinations for which this was previously thought unnecessary. For pathogenic yeasts, conventional phenotypic testing needs at least 24 h. Culture on a porous aluminum oxide (PAO) support combined with microscopy offers a route to more rapid results. Microcolonies of Candida species grown on PAO were stained with the fluorogenic dyes Fun-1 and Calcofluor White and then imaged by fluorescence microscopy. Images were captured by a charge-coupled device camera and processed by publicly available software. By this method, the growth of yeasts could be detected and quantified within 2 h. Microcolony imaging was then used to assess the susceptibility of the yeasts to amphotericin B, anidulafungin and caspofungin (3.5 h culture), and voriconazole and itraconazole (7 h culture). Overall, the results showed good agreement with EUCAST (86.5% agreement; n = 170) and E-test (85.9% agreement; n = 170). The closest agreement to standard tests was found when testing susceptibility to amphotericin B and echinocandins (88.2 to 91.2%) and the least good for the triazoles (79.4 to 82.4%). Furthermore, large datasets on population variation could be rapidly obtained. An analysis of microcolonies revealed subtle effects of antimycotics on resistant strains and below the MIC of sensitive strains, particularly an increase in population heterogeneity and cell density-dependent effects of triazoles. Additionally, the method could be adapted to strain identification via germ tube extension. We suggest PAO culture is a rapid and versatile method that may be usefully adapted to clinical mycology and has research applications.

  17. Rapid susceptibility testing and microcolony analysis of Candida spp. cultured and imaged on porous aluminum oxide.

    Directory of Open Access Journals (Sweden)

    Colin J Ingham

    Full Text Available BACKGROUND: Acquired resistance to antifungal agents now supports the introduction of susceptibility testing for species-drug combinations for which this was previously thought unnecessary. For pathogenic yeasts, conventional phenotypic testing needs at least 24 h. Culture on a porous aluminum oxide (PAO support combined with microscopy offers a route to more rapid results. METHODS: Microcolonies of Candida species grown on PAO were stained with the fluorogenic dyes Fun-1 and Calcofluor White and then imaged by fluorescence microscopy. Images were captured by a charge-coupled device camera and processed by publicly available software. By this method, the growth of yeasts could be detected and quantified within 2 h. Microcolony imaging was then used to assess the susceptibility of the yeasts to amphotericin B, anidulafungin and caspofungin (3.5 h culture, and voriconazole and itraconazole (7 h culture. SIGNIFICANCE: Overall, the results showed good agreement with EUCAST (86.5% agreement; n = 170 and E-test (85.9% agreement; n = 170. The closest agreement to standard tests was found when testing susceptibility to amphotericin B and echinocandins (88.2 to 91.2% and the least good for the triazoles (79.4 to 82.4%. Furthermore, large datasets on population variation could be rapidly obtained. An analysis of microcolonies revealed subtle effects of antimycotics on resistant strains and below the MIC of sensitive strains, particularly an increase in population heterogeneity and cell density-dependent effects of triazoles. Additionally, the method could be adapted to strain identification via germ tube extension. We suggest PAO culture is a rapid and versatile method that may be usefully adapted to clinical mycology and has research applications.

  18. Microdose acquisition in adolescent leg length discrepancy using a low-dose biplane imaging system

    DEFF Research Database (Denmark)

    Jensen, Janni; Mussmann, Bo Redder; Hjarbæk, John

    2017-01-01

    Background Children with leg length discrepancy often undergo repeat imaging. Therefore, every effort to reduce radiation dose is important. Using low dose preview images and noise reduction software rather than diagnostic images for length measurements might contribute to reducing dose. Purpose ...

  19. Imageability Predicts the Age of Acquisition of Verbs in Chinese Children

    Science.gov (United States)

    Ma, Weiyi; Golinkoff, Roberta Michnick; Hirsh-Pasek, Kathy; McDonough, Colleen; Tardif, Twila

    2009-01-01

    Verbs are harder to learn than nouns in English and in many other languages, but are relatively easy to learn in Chinese. This paper evaluates one potential explanation for these findings by examining the construct of imageability, or the ability of a word to produce a mental image. Chinese adults rated the imageability of Chinese words from the…

  20. Cranial nerve assessment in cavernous sinus tumors with contrast-enhanced 3D fast-imaging employing steady-state acquisition MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Amemiya, Shiori; Aoki, Shigeki; Ohtomo, Kuni [University of Tokyo, Department of Radiology, Graduate School of Medicine, Bunkyo-ku, Tokyo (Japan)

    2009-07-15

    The purpose of this study is to apply contrast-enhanced 3D fast-imaging employing steady-state acquisition (3D-FIESTA) imaging to the evaluation of cranial nerves (CN) in patients with cavernous sinus tumors. Contrast-enhanced 3D-FIESTA images were acquired from ten patients with cavernous sinus tumors with a 3-T unit. In all cases, the trigeminal nerve with tumor involvement was easily identified in the cavernous portions. Although oculomotor and abducens nerves were clearly visualized against the tumor area with intense contrast enhancement, they were hardly identifiable within the area lacking contrast enhancement. The trochlear nerve was visualized in part, but not delineated as a linear structure outside of the lesion. Contrast-enhanced 3D-FIESTA can be useful in the assessment of cranial nerves in and around the cavernous sinus with tumor involvement. (orig.)

  1. Optimization of an on-board imaging system for extremely rapid radiation therapy

    Science.gov (United States)

    Cherry Kemmerling, Erica M.; Wu, Meng; Yang, He; Maxim, Peter G.; Loo, Billy W.; Fahrig, Rebecca

    2015-01-01

    Purpose: Next-generation extremely rapid radiation therapy systems could mitigate the need for motion management, improve patient comfort during the treatment, and increase patient throughput for cost effectiveness. Such systems require an on-board imaging system that is competitively priced, fast, and of sufficiently high quality to allow good registration between the image taken on the day of treatment and the image taken the day of treatment planning. In this study, three different detectors for a custom on-board CT system were investigated to select the best design for integration with an extremely rapid radiation therapy system. Methods: Three different CT detectors are proposed: low-resolution (all 4 × 4 mm pixels), medium-resolution (a combination of 4 × 4 mm pixels and 2 × 2 mm pixels), and high-resolution (all 1 × 1 mm pixels). An in-house program was used to generate projection images of a numerical anthropomorphic phantom and to reconstruct the projections into CT datasets, henceforth called “realistic” images. Scatter was calculated using a separate Monte Carlo simulation, and the model included an antiscatter grid and bowtie filter. Diagnostic-quality images of the phantom were generated to represent the patient scan at the time of treatment planning. Commercial deformable registration software was used to register the diagnostic-quality scan to images produced by the various on-board detector configurations. The deformation fields were compared against a “gold standard” deformation field generated by registering initial and deformed images of the numerical phantoms that were used to make the diagnostic and treatment-day images. Registrations of on-board imaging system data were judged by the amount their deformation fields differed from the corresponding gold standard deformation fields—the smaller the difference, the better the system. To evaluate the registrations, the pointwise distance between gold standard and realistic registration

  2. CD-SEM image acquisition effects on 193-nm resists line slimming

    Science.gov (United States)

    Sullivan, Neal T.; Mastovich, Martin E.; Bowdoin, Scott; Brandom, Robert

    2003-05-01

    ArF resist slimming under electron beam exposure introduces significant measurement uncertainty in the metrology of 193nm resists. Previous studies have demonstrated the primary effect of electron landing energy on ArF resist line slimming; this work examines the influence of acquisition time, beam blanking, probe current and measurement magnification. This work will demonstrate, in concurrence with other research, that reducing landing energy remains the most effective method for minimizing line slimming of ArF resist under electron beam exposure. However, the other parameters studied can also affect the magnitude of line slimming. This becomes especially important for line edge roughness (LER) measurements which require a greater total dose be imparted to the sample to maintain measurement precision. Control over all acquisition parameters is essential to achieve accurate and repeatable LER measurements.

  3. A new acquisition and imaging system for environmental measurements: an experience on the Italian cultural heritage.

    Science.gov (United States)

    Leccese, Fabio; Cagnetti, Marco; Calogero, Andrea; Trinca, Daniele; di Pasquale, Stefano; Giarnetti, Sabino; Cozzella, Lorenzo

    2014-05-23

    A new acquisition system for remote control of wall paintings has been realized and tested in the field. The system measures temperature and atmospheric pressure in an archeological site where a fresco has been put under control. The measuring chain has been designed to be used in unfavorable environments where neither electric power nor telecommunication infrastructures are available. The environmental parameters obtained from the local monitoring are then transferred remotely allowing an easier management by experts in the field of conservation of cultural heritage. The local acquisition system uses an electronic card based on microcontrollers and sends the data to a central unit realized with a Raspberry-Pi. The latter manages a high quality camera to pick up pictures of the fresco. Finally, to realize the remote control at a site not reached by internet signals, a WiMAX connection based on different communication technologies such as WiMAX, Ethernet, GPRS and Satellite, has been set up.

  4. A New Acquisition and Imaging System for Environmental Measurements: An Experience on the Italian Cultural Heritage

    Directory of Open Access Journals (Sweden)

    Fabio Leccese

    2014-05-01

    Full Text Available A new acquisition system for remote control of wall paintings has been realized and tested in the field. The system measures temperature and atmospheric pressure in an archeological site where a fresco has been put under control. The measuring chain has been designed to be used in unfavorable environments where neither electric power nor telecommunication infrastructures are available. The environmental parameters obtained from the local monitoring are then transferred remotely allowing an easier management by experts in the field of conservation of cultural heritage. The local acquisition system uses an electronic card based on microcontrollers and sends the data to a central unit realized with a Raspberry-Pi. The latter manages a high quality camera to pick up pictures of the fresco. Finally, to realize the remote control at a site not reached by internet signals, a WiMAX connection based on different communication technologies such as WiMAX, Ethernet, GPRS and Satellite, has been set up.

  5. How Lovebirds Maneuver Rapidly Using Super-Fast Head Saccades and Image Feature Stabilization.

    Directory of Open Access Journals (Sweden)

    Daniel Kress

    Full Text Available Diurnal flying animals such as birds depend primarily on vision to coordinate their flight path during goal-directed flight tasks. To extract the spatial structure of the surrounding environment, birds are thought to use retinal image motion (optical flow that is primarily induced by motion of their head. It is unclear what gaze behaviors birds perform to support visuomotor control during rapid maneuvering flight in which they continuously switch between flight modes. To analyze this, we measured the gaze behavior of rapidly turning lovebirds in a goal-directed task: take-off and fly away from a perch, turn on a dime, and fly back and land on the same perch. High-speed flight recordings revealed that rapidly turning lovebirds perform a remarkable stereotypical gaze behavior with peak saccadic head turns up to 2700 degrees per second, as fast as insects, enabled by fast neck muscles. In between saccades, gaze orientation is held constant. By comparing saccade and wingbeat phase, we find that these super-fast saccades are coordinated with the downstroke when the lateral visual field is occluded by the wings. Lovebirds thus maximize visual perception by overlying behaviors that impair vision, which helps coordinate maneuvers. Before the turn, lovebirds keep a high contrast edge in their visual midline. Similarly, before landing, the lovebirds stabilize the center of the perch in their visual midline. The perch on which the birds land swings, like a branch in the wind, and we find that retinal size of the perch is the most parsimonious visual cue to initiate landing. Our observations show that rapidly maneuvering birds use precisely timed stereotypic gaze behaviors consisting of rapid head turns and frontal feature stabilization, which facilitates optical flow based flight control. Similar gaze behaviors have been reported for visually navigating humans. This finding can inspire more effective vision-based autopilots for drones.

  6. How Lovebirds Maneuver Rapidly Using Super-Fast Head Saccades and Image Feature Stabilization

    Science.gov (United States)

    Kress, Daniel; van Bokhorst, Evelien; Lentink, David

    2015-01-01

    Diurnal flying animals such as birds depend primarily on vision to coordinate their flight path during goal-directed flight tasks. To extract the spatial structure of the surrounding environment, birds are thought to use retinal image motion (optical flow) that is primarily induced by motion of their head. It is unclear what gaze behaviors birds perform to support visuomotor control during rapid maneuvering flight in which they continuously switch between flight modes. To analyze this, we measured the gaze behavior of rapidly turning lovebirds in a goal-directed task: take-off and fly away from a perch, turn on a dime, and fly back and land on the same perch. High-speed flight recordings revealed that rapidly turning lovebirds perform a remarkable stereotypical gaze behavior with peak saccadic head turns up to 2700 degrees per second, as fast as insects, enabled by fast neck muscles. In between saccades, gaze orientation is held constant. By comparing saccade and wingbeat phase, we find that these super-fast saccades are coordinated with the downstroke when the lateral visual field is occluded by the wings. Lovebirds thus maximize visual perception by overlying behaviors that impair vision, which helps coordinate maneuvers. Before the turn, lovebirds keep a high contrast edge in their visual midline. Similarly, before landing, the lovebirds stabilize the center of the perch in their visual midline. The perch on which the birds land swings, like a branch in the wind, and we find that retinal size of the perch is the most parsimonious visual cue to initiate landing. Our observations show that rapidly maneuvering birds use precisely timed stereotypic gaze behaviors consisting of rapid head turns and frontal feature stabilization, which facilitates optical flow based flight control. Similar gaze behaviors have been reported for visually navigating humans. This finding can inspire more effective vision-based autopilots for drones. PMID:26107413

  7. How Lovebirds Maneuver Rapidly Using Super-Fast Head Saccades and Image Feature Stabilization.

    Science.gov (United States)

    Kress, Daniel; van Bokhorst, Evelien; Lentink, David

    2015-01-01

    Diurnal flying animals such as birds depend primarily on vision to coordinate their flight path during goal-directed flight tasks. To extract the spatial structure of the surrounding environment, birds are thought to use retinal image motion (optical flow) that is primarily induced by motion of their head. It is unclear what gaze behaviors birds perform to support visuomotor control during rapid maneuvering flight in which they continuously switch between flight modes. To analyze this, we measured the gaze behavior of rapidly turning lovebirds in a goal-directed task: take-off and fly away from a perch, turn on a dime, and fly back and land on the same perch. High-speed flight recordings revealed that rapidly turning lovebirds perform a remarkable stereotypical gaze behavior with peak saccadic head turns up to 2700 degrees per second, as fast as insects, enabled by fast neck muscles. In between saccades, gaze orientation is held constant. By comparing saccade and wingbeat phase, we find that these super-fast saccades are coordinated with the downstroke when the lateral visual field is occluded by the wings. Lovebirds thus maximize visual perception by overlying behaviors that impair vision, which helps coordinate maneuvers. Before the turn, lovebirds keep a high contrast edge in their visual midline. Similarly, before landing, the lovebirds stabilize the center of the perch in their visual midline. The perch on which the birds land swings, like a branch in the wind, and we find that retinal size of the perch is the most parsimonious visual cue to initiate landing. Our observations show that rapidly maneuvering birds use precisely timed stereotypic gaze behaviors consisting of rapid head turns and frontal feature stabilization, which facilitates optical flow based flight control. Similar gaze behaviors have been reported for visually navigating humans. This finding can inspire more effective vision-based autopilots for drones.

  8. Rapid determination of biogenic amines in cooked beef using hyperspectral imaging with sparse representation algorithm

    Science.gov (United States)

    Yang, Dong; Lu, Anxiang; Ren, Dong; Wang, Jihua

    2017-11-01

    This study explored the feasibility of rapid detection of biogenic amines (BAs) in cooked beef during the storage process using hyperspectral imaging technique combined with sparse representation (SR) algorithm. The hyperspectral images of samples were collected in the two spectral ranges of 400-1000 nm and 1000-1800 nm, separately. The spectral data were reduced dimensionality by SR and principal component analysis (PCA) algorithms, and then integrated the least square support vector machine (LS-SVM) to build the SR-LS-SVM and PC-LS-SVM models for the prediction of BAs values in cooked beef. The results showed that the SR-LS-SVM model exhibited the best predictive ability with determination coefficients (RP2) of 0.943 and root mean square errors (RMSEP) of 1.206 in the range of 400-1000 nm of prediction set. The SR and PCA algorithms were further combined to establish the best SR-PC-LS-SVM model for BAs prediction, which had high RP2of 0.969 and low RMSEP of 1.039 in the region of 400-1000 nm. The visual map of the BAs was generated using the best SR-PC-LS-SVM model with imaging process algorithms, which could be used to observe the changes of BAs in cooked beef more intuitively. The study demonstrated that hyperspectral imaging technique combined with sparse representation were able to detect effectively the BAs values in cooked beef during storage and the built SR-PC-LS-SVM model had a potential for rapid and accurate determination of freshness indexes in other meat and meat products.

  9. Rapid non-contrast magnetic resonance imaging for post appendectomy intra-abdominal abscess in children

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Megan H. [Washington University School of Medicine in St. Louis, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Eutsler, Eric P.; Khanna, Geetika [Washington University School of Medicine in St. Louis, Pediatric Radiology, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Sheybani, Elizabeth F. [Mercy Hospital St. Louis, Department of Radiology, St. Louis, MO (United States)

    2017-07-15

    Acute appendicitis, especially if perforated at presentation, is often complicated by postoperative abscess formation. The detection of a postoperative abscess relies primarily on imaging. This has traditionally been done with contrast-enhanced computed tomography. Non-contrast magnetic resonance imaging (MRI) has the potential to accurately detect intra-abdominal abscesses, especially with the use of diffusion-weighted imaging (DWI). To evaluate our single-center experience with a rapid non-contrast MRI protocol evaluating post-appendectomy abscesses in children with persistent postsurgical symptoms. In this retrospective, institutional review board-approved study, all patients underwent a clinically indicated non-contrast 1.5- or 3-Tesla abdomen/pelvis MRI consisting of single-shot fast spin echo, inversion recovery and DWI sequences. All MRI studies were reviewed by two blinded pediatric radiologists to identify the presence of a drainable fluid collection. Each fluid collection was further characterized as accessible or not accessible for percutaneous or transrectal drainage. Imaging findings were compared to clinical outcome. Seven of the 15 patients had a clinically significant fluid collection, and 5 of these patients were treated with percutaneous drain placement or exploratory laparotomy. The other patients had a phlegmon or a clinically insignificant fluid collection and were discharged home within 48 h. Rapid non-contrast MRI utilizing fluid-sensitive and DWI sequences can be used to identify drainable fluid collections in post-appendectomy patients. This protocol can be used to triage patients between conservative management vs. abscess drainage without oral/intravenous contrast or exposure to ionizing radiation. (orig.)

  10. Low radiation dose C-arm cone-beam CT based on prior image constrained compressed sensing (PICCS): including compensation for image volume mismatch between multiple data acquisitions

    Science.gov (United States)

    Nett, Brian; Tang, Jie; Aagaard-Kienitz, Beverly; Rowley, Howard; Chen, Guang-Hong

    2009-02-01

    C-arm based cone-beam CT (CBCT) has evolved into a routine clinical imaging modality to provide threedimensional tomographic image guidance before, during, and after an interventional procedure. It is often used to update the clinician to the state of the patient anatomy and interventional tool placement. Due to the repeatedly use of CBCT, the accumulated radiation dose in an interventional procedure has become a concern. There is a strong desire from both patients and health care providers to reduce the radiation exposure required for these exams. The overall objective of this work is to propose and validate a method to significantly reduce the total radiation dose used during a CBCT image guided intervention. The basic concept is that the first cone-beam CT scan acquired at the full dose will be used to constrain the reconstruction of the later CBCT scans acquired at a much lower radiation dose. A recently developed new image reconstruction algorithm, Prior Image Constrained Compressed Sensing (PICCS), was used to reconstruct subsequent CBCT images with lower dose. This application differs from other applications of the PICCS algorithm, such as time-resolved CT or fourdimensional CBCT (4DCBCT), because the patient position may be frequently changed from one CBCT scan to another during the procedure. Thus, an image registration step to account for the change in patient position is indispensable for use of the PICCS image reconstruction algorithm. In this paper, the image registration step is combined with the PICCS algorithm to enable radiation dose reduction in CBCT image guided interventions. Experimental results acquired from a clinical C-arm system using a human cadaver were used to validate the PICCS algorithm based radiation dose reduction scheme. Using the proposed method in this paper, it has been demonstrated that, instead of 300 view angles, this technique requires about 20 cone-beam view angles to reconstruct CBCT angiograms. This signals a radiation

  11. IMAGO: a complete system for acquisition, processing, two/three-dimensional and temporal display of microscopic bio-images.

    Science.gov (United States)

    Diaspro, A; Adami, M; Sartore, M; Nicolini, C

    1990-01-01

    This work describes IMAGO, an integrated bio-imaging system developed in our laboratory. The whole system consists of a personal computer, a commercially available frame grabber directly plugged into a personal computer, video input/output modules, specific hardware for z-axis movement and light shuttering, and a software package. IMAGO is user-friendly, menu driven and enables one to perform image acquisition with different methods: optical sectioning, flashing epifluorescence, transmitted and phase contrast microscopy. It makes various functions possible, including: image transfer, gray scale processing, conventional and advanced filtering, logical operations, look-up table management, three-dimensional (3D) editing, 3D representation and auto-correlation techniques. More than 100 image processing functions have been implemented and can be easily managed through IMAGO. Examples are given in the area of biophysical research, like 3D representation of nuclei and of electron microscopic images, in situ microscopy of living cells. IMAGO processes information in an x, y, z, t space.

  12. Acquisition of 3D urban models by analysis of aerial images, digital surface models, and existing 2D building information

    Science.gov (United States)

    Haala, Norbert; Anders, Karl-Heinrich

    1997-08-01

    For a task like 3D building reconstruction, there are three main data sources carrying information which is reburied for a highly automated data acquisition. These data sources are aerial images, digital surface models (DSM), which can either be derived by stereo matching from aerial images or be directly measured by scanning laser systems, and -- at least for highly developed countries -- existing (2D) GIS information on the ground plan or usage of buildings. The way these different data sources should be utilized by a process of 3D building reconstruction depends on the distinctive characteristics of the different, partly complementary type of information they contain. Image data contains much information, but just this complexity causes enormous problems for the automatic interpretation of this data type. The GIS as a secondary data source provides information on the 2D shape, i.e. the ground plan of a building, which is very reliable, although information on the third dimension is missing and therefore has to be provided by other data sources. As the information of a DSM is restricted to surface geometry, the interpretation of this kind of data is easier compared to the interpretation of image data. Nevertheless, due to insufficient spatial resolution or quality of the DSM, optimal results can only be achieved by the combination of all data sources. Within this paper two approaches aiming on the combination of aerial images, digital surface models and existing ground plans for the reconstruction of three- dimensional building reconstructions are demonstrated.

  13. Clinical evaluation of PET image quality as a function of acquisition time in a new TOF-PET/MR compared to TOF-PET/CT - initial results

    Energy Technology Data Exchange (ETDEWEB)

    Zeimpekis, Konstantinos; Huellner, Martin; De Galiza Barbosa, Felipe; Ter Voert, Edwin; Davison, Helen; Delso, Gaspar; Veit-Haibach, Patrick [Nuclear Medicine, University Hospital Zurich (Switzerland)

    2015-05-18

    The recently available integrated PET/MR imaging can offer significant additional advances in clinical imaging. The purpose of this study was to compare the PET performance between a PET/CT scanner and an integrated TOF-PET/MR scanner concerning image quality parameters and quantification in terms of SUV as a function of acquisition time (a surrogate of dose). Five brain and five whole body patients were included in the study. The PET/CT scan was used as a reference and the PET/MR acquisition time was consecutively adjusted, taking into account the decay between the scans in order to expose both systems to the same amount of emitted signal. The acquisition times were then retrospectively reduced to assess the performance of the PET/MRI for lower count rates. Image quality, image sharpness, artifacts and noise were evaluated. SUV measurements were taken in the liver and in white matter to compare quantification. Quantitative evaluation showed good correlation between PET/CT and PET/MR brain SUVs. Liver correlation was lower, with uptake underestimation in PET/MR, partially justified by bio-redistribution. The clinical evaluation showed that PET/MR offers higher image quality and sharpness with lower levels of noise and artefacts compared to PET/CT with reduced acquisition times for whole body scans, while for brain scans there is no significant difference. The PET-component of the TOF-PET/MR showed higher image quality compared to PET/CT as tested with reduced imaging times. However, these results account mainly for body imaging, while no significant difference were found in brain imaging. This overall higher image quality suggests that the acquisition time or injected activity can be reduced by at least 37% on the PET/MR scanner.

  14. JMorph: Software for performing rapid morphometric measurements on digital images of fossil assemblages

    Science.gov (United States)

    Lelièvre, Peter G.; Grey, Melissa

    2017-08-01

    Quantitative morphometric analyses of form are widely used in palaeontology, especially for taxonomic and evolutionary research. These analyses can involve several measurements performed on hundreds or even thousands of samples. Performing measurements of size and shape on large assemblages of macro- or microfossil samples is generally infeasible or impossible with traditional instruments such as vernier calipers. Instead, digital image processing software is required to perform measurements via suitable digital images of samples. Many software packages exist for morphometric analyses but there is not much available for the integral stage of data collection, particularly for the measurement of the outlines of samples. Some software exists to automatically detect the outline of a fossil sample from a digital image. However, automatic outline detection methods may perform inadequately when samples have incomplete outlines or images contain poor contrast between the sample and staging background. Hence, a manual digitization approach may be the only option. We are not aware of any software packages that are designed specifically for efficient digital measurement of fossil assemblages with numerous samples, especially for the purposes of manual outline analysis. Throughout several previous studies, we have developed a new software tool, JMorph, that is custom-built for that task. JMorph provides the means to perform many different types of measurements, which we describe in this manuscript. We focus on JMorph's ability to rapidly and accurately digitize the outlines of fossils. JMorph is freely available from the authors.

  15. A user report on the trial use of gesture commands for image manipulation and X-ray acquisition.

    Science.gov (United States)

    Li, Ellis Chun Fai; Lai, Christopher Wai Keung

    2016-07-01

    Touchless environment for image manipulation and X-ray acquisition may enhance the current infection control measure during X-ray examination simply by avoiding any touch on the control panel. The present study is intended at designing and performing a trial experiment on using motion-sensing technology to perform image manipulation and X-ray acquisition function (the activities a radiographer frequently performs during an X-ray examination) under an experimental setup. Based on the author's clinical experience, several gesture commands were designed carefully to complete a single X-ray examination. Four radiographers were randomly recruited for the study. They were asked to perform gesture commands in front of a computer integrated with a gesture-based touchless controller. The translational movements of the tip of their thumb and index finger while performing different gesture commands were recorded for analysis. Although individual operators were free to decide the extent of movement and the speed at which their fingers and thumbs moved while performing these gesture commands, the result of our study demonstrated that all operators could perform our proposed gesture commands with good consistency, suggesting that motion-sensing technology could, in practice, be integrated into radiographic examinations. To summarize, although the implementation of motion-sensing technology as an input command in radiographic examination might inevitably slow down the examination throughput considering that extra procedural steps are required to trigger specific gesture commands in sequence, it is advantageous in minimizing the potential of the pathogen contamination during image operation and image processing that leads to cross infection.

  16. Rapid total body fat measurement by magnetic resonance imaging: quantification and topography; Schnelle Ganzkoerperfettmessung mittels MRT: Quantifizierung und Topografie

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, F.M.; Hunold, P.; Greiff, A. de; Nuefer, M.; Barkhausen, J.; Ladd, S.C. [Uniklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie; Ruehm, S. [David Geffen School of Medicine at UCLA (United States). Dept. of Radiology

    2007-05-15

    Purpose: To evaluate a rapid and comprehensive MR protocol based on a T1-weighted sequence in conjunction with a rolling table platform for the quantification of total body fat. Materials and Methods: 11 healthy volunteers and 50 patients were included in the study. MR data was acquired on a 1.5-T system (Siemens Magnetom Sonata). An axial T1-weighted flash 2D sequence (TR 101, TE 4.7, FA 70, FOV 50 cm, 205 x 256 matrix, slice thickness: 10 mm, 10 mm interslice gap) was used for data acquisition. Patients were placed in a supine position on a rolling table platform capable of acquiring multiple consecutive data sets by pulling the patient through the isocenter of the magnet. Data sets extending from the upper to lower extremities were collected. The images were analyzed with respect to the amount of intraabdominal, subcutaneous and total abdominal fat by semi-automated image segmentation software that employs a contour-following algorithm. Results: The obtained MR images were able to be evaluated for all volunteers and patients. Excellent correlation was found between whole body MRI results in volunteers with DEXA (r{sup 2} = 0.95) and bioimpedance (r{sup 2} = 0.89) measurements, while the correlation coefficient was 0.66 between MRI and BMI, indicating only moderate reliability of the BMI method. Variations in patients with respect to the amount of total, subcutaneous, and intraabdominal adipose tissue was not related to standard anthropometric measurements and metabolic lipid profiles (r{sup 2} = 0,001 to 0.48). The results showed that there was a significant variation in intraabdominal adipose tissue which could not be predicted from the total body fat (r{sup 2} = 0.14) or subcutaneous adipose tissue (r{sup 2} = 0.04). Although no significant differences in BMI could be found between females and males (p = 0.26), females showed significantly higher total and subcutaneous abdominal adipose tissue (p < 0.05). Conclusion. (orig.)

  17. Rapid diagnosis and intraoperative margin assessment of human lung cancer with fluorescence lifetime imaging microscopy

    Directory of Open Access Journals (Sweden)

    Mengyan Wang

    2017-12-01

    Full Text Available A method of rapidly differentiating lung tumor from healthy tissue is extraordinarily needed for both the diagnosis and the intraoperative margin assessment. We assessed the ability of fluorescence lifetime imaging microscopy (FLIM for differentiating human lung cancer and normal tissues with the autofluorescence, and also elucidated the mechanism in tissue studies and cell studies. A 15-patient testing group was used to compare FLIM results with traditional histopathology diagnosis. Based on the endogenous fluorescence lifetimes of the testing group, a criterion line was proposed to distinguish normal and cancerous tissues. Then by blinded examined 41 sections from the validation group of other 16 patients, the sensitivity and specificity of FLIM were determined. The cellular metabolism was studied with specific perturbations of oxidative phosphorylation and glycolysis in cell studies. The fluorescence lifetime of cancerous lung tissues is consistently lower than normal tissues, and this is due to the both decrease of reduced nicotinamide adenine dinucleotide (NADH and flavin adenine dinucleotide (FAD lifetimes. A criterion line of lifetime at 1920 ps can be given for differentiating human lung cancer and normal tissues.The sensitivity and specificity of FLIM for lung cancer diagnosis were determined as 92.9% and 92.3%. These findings suggest that NADH and FAD can be used to rapidly diagnose lung cancer. FLIM is a rapid, accurate and highly sensitive technique in the judgment during lung cancer surgery and it can be potential in earlier cancer detection.

  18. Rapid diagnosis and intraoperative margin assessment of human lung cancer with fluorescence lifetime imaging microscopy.

    Science.gov (United States)

    Wang, Mengyan; Tang, Feng; Pan, Xiaobo; Yao, Longfang; Wang, Xinyi; Jing, Yueyue; Ma, Jiong; Wang, Guifang; Mi, Lan

    2017-12-01

    A method of rapidly differentiating lung tumor from healthy tissue is extraordinarily needed for both the diagnosis and the intraoperative margin assessment. We assessed the ability of fluorescence lifetime imaging microscopy (FLIM) for differentiating human lung cancer and normal tissues with the autofluorescence, and also elucidated the mechanism in tissue studies and cell studies. A 15-patient testing group was used to compare FLIM results with traditional histopathology diagnosis. Based on the endogenous fluorescence lifetimes of the testing group, a criterion line was proposed to distinguish normal and cancerous tissues. Then by blinded examined 41 sections from the validation group of other 16 patients, the sensitivity and specificity of FLIM were determined. The cellular metabolism was studied with specific perturbations of oxidative phosphorylation and glycolysis in cell studies. The fluorescence lifetime of cancerous lung tissues is consistently lower than normal tissues, and this is due to the both decrease of reduced nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) lifetimes. A criterion line of lifetime at 1920 ps can be given for differentiating human lung cancer and normal tissues.The sensitivity and specificity of FLIM for lung cancer diagnosis were determined as 92.9% and 92.3%. These findings suggest that NADH and FAD can be used to rapidly diagnose lung cancer. FLIM is a rapid, accurate and highly sensitive technique in the judgment during lung cancer surgery and it can be potential in earlier cancer detection.

  19. Quantitative assessment of parallel acquisition techniques in diffusion tensor imaging at 3.0 Tesla.

    Science.gov (United States)

    Ardekani, S; Sinha, U

    2004-01-01

    Single shot echo-planar based diffusion tensor imaging is prone to geometric and intensity distortions which scale with the magnetic field. Parallel imaging is a means of reducing these distortions while preserving spatial resolution. A quantitative comparison at 3 T of parallel imaging for diffusion tensor sequences using k-space (GRAPPA) and image domain (SENSE) reconstructions is reported here. Indices quantifying distortions, artifacts and reliability were compared for all voxels in the corpus callosum and showed that GRAPPA with an acceleration factor of 2 was the optimal sequence.

  20. Optimization of Sample Preparation and Instrumental Parameters for the Rapid Analysis of Drugs of Abuse in Hair samples by MALDI-MS/MS Imaging

    Science.gov (United States)

    Flinders, Bryn; Beasley, Emma; Verlaan, Ricky M.; Cuypers, Eva; Francese, Simona; Bassindale, Tom; Clench, Malcolm R.; Heeren, Ron M. A.

    2017-08-01

    Matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) has been employed to rapidly screen longitudinally sectioned drug user hair samples for cocaine and its metabolites using continuous raster imaging. Optimization of the spatial resolution and raster speed were performed on intact cocaine contaminated hair samples. The optimized settings (100 × 150 μm at 0.24 mm/s) were subsequently used to examine longitudinally sectioned drug user hair samples. The MALDI-MS/MS images showed the distribution of the most abundant cocaine product ion at m/z 182. Using the optimized settings, multiple hair samples obtained from two users were analyzed in approximately 3 h: six times faster than the standard spot-to-spot acquisition method. Quantitation was achieved using longitudinally sectioned control hair samples sprayed with a cocaine dilution series. A multiple reaction monitoring (MRM) experiment was also performed using the `dynamic pixel' imaging method to screen for cocaine and a range of its metabolites, in order to differentiate between contaminated hairs and drug users. Cocaine, benzoylecgonine, and cocaethylene were detectable, in agreement with analyses carried out using the standard LC-MS/MS method. [Figure not available: see fulltext.

  1. IQ SPECT allows a significant reduction in administered dose and acquisition time for myocardial perfusion imaging: evidence from a phantom study.

    Science.gov (United States)

    Caobelli, Federico; Kaiser, Stefano Ren; Thackeray, James T; Bengel, Frank M; Chieregato, Matteo; Soffientini, Alberto; Pizzocaro, Claudio; Savelli, Giordano; Galelli, Marco; Guerra, Ugo Paolo

    2014-12-01

    We recently demonstrated in a clinical trial the ability of a new protocol, IQ SPECT, to acquire myocardial perfusion imaging (MPI) studies in a quarter of the time (12 s/view) of the standard protocol, with preserved diagnostic accuracy. We now aim to establish the lower limit of radioactivity that can be administered to patients and the minimum acquisition time in SPECT MPI using an IQ SPECT protocol, while preserving diagnostic accuracy. An anthropomorphic cardiac phantom was used to acquire clinical rest scans with a simulated in vivo distribution of (99m)Tc-tetrofosmin at full dose (740 MBq) and at doses equal to 50%, 25%, and 18%. For each dose, 2 sets of images were acquired, with and without a transmural defect (TD). Variable acquisition times were also used for each dose. We analyzed raw data and reconstructed images, including no correction and correction for attenuation (AC), for scatter (SC), or for both (ACSC). Images were evaluated qualitatively and quantitatively in order to assess left ventricle (LV) wall thickness (full width at half maximum of the medial sections), TD, and cavity contrast in the LV wall. Data were compared across different acquisition times within the same dose and across doses with the same acquisition time. Images were visually scored as very-good quality except those acquired with 4 s/view or less at 100% dose and 6 s/view or less with 50%, 25%, or 18% dose, due to false-positive defects. LV wall thickness was not significantly different among all acquisitions. Cavity contrast remained unchanged within the same dose for all images and tended to be higher in AC and ACSC images. TD contrast remained unchanged within the same dose for all images. In SC and no-correction images, contrast was constant for all doses. AC images had significantly higher TD contrast values, and ACSC images showed a drop in TD contrast for a 50% dose. IQ SPECT effectively preserved both image quality and quantitative measurements with reduced acquisition

  2. TOD Predicts Target Acquisition Performance for Staring and Scanning Thermal Imagers

    NARCIS (Netherlands)

    Bijl, P.; Valeton, J.M.; Jong, A.N. de

    2000-01-01

    Identification and recognition performance for four staring and two scanning thermal imagers, were measured in an observer experiment using images that were collected during a NATO field trial in Nettuno, Italy, in 1998. The dataset allows validation of the MRTD and alternative sensor performance

  3. The influence of the microscope lamp filament colour temperature on the process of digital images of histological slides acquisition standardization.

    Science.gov (United States)

    Korzynska, Anna; Roszkowiak, Lukasz; Pijanowska, Dorota; Kozlowski, Wojciech; Markiewicz, Tomasz

    2014-01-01

    The aim of this study is to compare the digital images of the tissue biopsy captured with optical microscope using bright field technique under various light conditions. The range of colour's variation in immunohistochemically stained with 3,3'-Diaminobenzidine and Haematoxylin tissue samples is immense and coming from various sources. One of them is inadequate setting of camera's white balance to microscope's light colour temperature. Although this type of error can be easily handled during the stage of image acquisition, it can be eliminated with use of colour adjustment algorithms. The examination of the dependence of colour variation from microscope's light temperature and settings of the camera is done as an introductory research to the process of automatic colour standardization. Six fields of view with empty space among the tissue samples have been selected for analysis. Each field of view has been acquired 225 times with various microscope light temperature and camera white balance settings. The fourteen randomly chosen images have been corrected and compared, with the reference image, by the following methods: Mean Square Error, Structural SIMilarity and visual assessment of viewer. For two types of backgrounds and two types of objects, the statistical image descriptors: range, median, mean and its standard deviation of chromaticity on a and b channels from CIELab colour space, and luminance L, and local colour variability for objects' specific area have been calculated. The results have been averaged for 6 images acquired in the same light conditions and camera settings for each sample. The analysis of the results leads to the following conclusions: (1) the images collected with white balance setting adjusted to light colour temperature clusters in certain area of chromatic space, (2) the process of white balance correction for images collected with white balance camera settings not matched to the light temperature moves image descriptors into proper

  4. Optical scatter imaging: a microscopic modality for the rapid morphological assay of living cells

    Science.gov (United States)

    Boustany, Nada N.

    2007-02-01

    Tumors derived from epithelial cells comprise the majority of human tumors and their growth results from the accumulation of multiple mutations affecting cellular processes critical for tissue homeostasis, including cell proliferation and cell death. To understand these processes and address the complexity of cancer cell function, multiple cellular responses to different experimental conditions and specific genetic mutations must be analyzed. Fundamental to this endeavor is the development of rapid cellular assays in genetically defined cells, and in particular, the development of optical imaging methods that allow dynamic observation and real-time monitoring of cellular processes. In this context, we are developing an optical scatter imaging technology that is intended to bridge the gap between light and electron microscopy by rapidly providing morphometric information about the relative size and shape of non-spherical organelles, with sub-wavelength resolution. Our goal is to complement current microscopy techniques used to study cells in-vitro, especially in long-term time-lapse studies of living cells, where exogenous labels can be toxic, and electron microscopy will destroy the sample. The optical measurements are based on Fourier spatial filtering in a standard microscope, and could ultimately be incorporated into existing high-throughput diagnostic platforms for cancer cell research and histopathology of neoplastic tissue arrays. Using an engineered epithelial cell model of tumor formation, we are currently studying how organelle structure and function are altered by defined genetic mutations affecting the propensity for cell death and oncogenic potential, and by environmental conditions promoting tumor growth. This talk will describe our optical scatter imaging technology and present results from our studies on apoptosis, and the function of BCL-2 family proteins.

  5. Technical Note: Rapid prototyping of 3D grid arrays for image guided therapy quality assurance

    Energy Technology Data Exchange (ETDEWEB)

    Kittle, David; Holshouser, Barbara; Slater, James M.; Guenther, Bob D.; Pitsianis, Nikos P.; Pearlstein, Robert D. [Department of Radiation Medicine, Epilepsy Radiosurgery Research Program, Loma Linda University, Loma Linda, California 92354 (United States); Department of Radiology, Loma Linda University Medical Center, Loma Linda, California 92354 (United States); Department of Radiation Medicine, Loma Linda University, Loma Linda, California 92354 (United States); Department of Physics, Duke University, Durham, North Carolina 27708 (United States); Department of Electrical and Computer Engineering and Department of Computer Science, Duke University, Durham, North Carolina 27708 (United States); Department of Radiation Medicine, Epilepsy Radiosurgery Research Program, Loma Linda University, Loma Linda, California 92354 and Department of Surgery-Neurosurgery, Duke University and Medical Center, Durham, North Carolina 27710 (United States)

    2008-12-15

    Three dimensional grid phantoms offer a number of advantages for measuring imaging related spatial inaccuracies for image guided surgery and radiotherapy. The authors examined the use of rapid prototyping technology for directly fabricating 3D grid phantoms from CAD drawings. We tested three different fabrication process materials, photopolymer jet with acrylic resin (PJ/AR), selective laser sintering with polyamide (SLS/P), and fused deposition modeling with acrylonitrile butadiene styrene (FDM/ABS). The test objects consisted of rectangular arrays of control points formed by the intersections of posts and struts (2 mm rectangular cross section) and spaced 8 mm apart in the x, y, and z directions. The PJ/AR phantom expanded after immersion in water which resulted in permanent warping of the structure. The surface of the FDM/ABS grid exhibited a regular pattern of depressions and ridges from the extrusion process. SLS/P showed the best combination of build accuracy, surface finish, and stability. Based on these findings, a grid phantom for assessing machine-dependent and frame-induced MR spatial distortions was fabricated to be used for quality assurance in stereotactic neurosurgical and radiotherapy procedures. The spatial uniformity of the SLS/P grid control point array was determined by CT imaging (0.6x0.6x0.625 mm{sup 3} resolution) and found suitable for the application, with over 97.5% of the control points located within 0.3 mm of the position specified in CAD drawing and none of the points off by more than 0.4 mm. Rapid prototyping is a flexible and cost effective alternative for development of customized grid phantoms for medical physics quality assurance.

  6. Image analysis in modern ophthalmology: from acquisition to computer assisted diagnosis and telemedicine

    Science.gov (United States)

    Marrugo, Andrés G.; Millán, María S.; Cristóbal, Gabriel; Gabarda, Salvador; Sorel, Michal; Sroubek, Filip

    2012-06-01

    Medical digital imaging has become a key element of modern health care procedures. It provides visual documentation and a permanent record for the patients, and most important the ability to extract information about many diseases. Modern ophthalmology thrives and develops on the advances in digital imaging and computing power. In this work we present an overview of recent image processing techniques proposed by the authors in the area of digital eye fundus photography. Our applications range from retinal image quality assessment to image restoration via blind deconvolution and visualization of structural changes in time between patient visits. All proposed within a framework for improving and assisting the medical practice and the forthcoming scenario of the information chain in telemedicine.

  7. Analysis of Crack Image Recognition Characteristics in Concrete Structures Depending on the Illumination and Image Acquisition Distance through Outdoor Experiments.

    Science.gov (United States)

    Cho, Hyun-Woo; Yoon, Hyuk-Jin; Yoon, Jae-Chan

    2016-10-06

    The effects of illumination and shooting distance on crack image recognition were investigated by examining cracks in images taken with a camera. In order to examine the effects, images of cracks in a concrete structure taken while varying the illumination and shooting distance in an outdoor environment were analyzed. The images were acquired at a daytime illumination of 52,000 lx and a night illumination of 13 lx. The crack specimen images produced for the experiment were taken by increasing the shooting distance from 5 m to 100 m in each illumination. On the basis of the analysis on the modulation transfer function (MTF) and contrast sensitivity of the crack images, the effects of illumination and shooting distance on the sharpness of the crack images were investigated. The minimum crack widths that can be identified under each illumination were analyzed using MTF10 and Weber contrast 0.1, respectively. It was found that as the shooting distance increases, the effects of illumination on crack recognition become greater.

  8. Analysis of Crack Image Recognition Characteristics in Concrete Structures Depending on the Illumination and Image Acquisition Distance through Outdoor Experiments

    Directory of Open Access Journals (Sweden)

    Hyun-Woo Cho

    2016-10-01

    Full Text Available The effects of illumination and shooting distance on crack image recognition were investigated by examining cracks in images taken with a camera. In order to examine the effects, images of cracks in a concrete structure taken while varying the illumination and shooting distance in an outdoor environment were analyzed. The images were acquired at a daytime illumination of 52,000 lx and a night illumination of 13 lx. The crack specimen images produced for the experiment were taken by increasing the shooting distance from 5 m to 100 m in each illumination. On the basis of the analysis on the modulation transfer function (MTF and contrast sensitivity of the crack images, the effects of illumination and shooting distance on the sharpness of the crack images were investigated. The minimum crack widths that can be identified under each illumination were analyzed using MTF10 and Weber contrast 0.1, respectively. It was found that as the shooting distance increases, the effects of illumination on crack recognition become greater.

  9. A Model for the Omnidirectional Acquisition and Rendering of Stereoscopic Images for Human Viewing

    Science.gov (United States)

    Gurrieri, Luis E.; Dubois, Eric

    2015-12-01

    Interactive visual media enable the visualization and navigation of remote-world locations in all gaze directions. A large segment of such media is created using pictures from the remote sites thanks to the advance in panoramic cameras. A desirable enhancement is to facilitate the stereoscopic visualization of remote scenes in all gaze directions. In this context, a model for the signal to be acquired by an omnistereoscopic sensor is needed in order to design better acquisition strategies. This omnistereoscopic viewing model must take into account the geometric constraints imposed by our binocular vision system since we want to produce stereoscopic imagery capable to induce stereopsis consistently in any gaze direction; in this paper, we present such model. In addition, we discuss different approaches to sample or to approximate this function and we propose a general acquisition model for sampling the omnistereoscopic light signal. From this model, we propose that by acquiring and mosaicking sparse sets of partially overlapped stereoscopic snapshots, a satisfactory illusion of depth can be evoked. Finally, we show an example of the rendering pipeline to create the omnistereoscopic imagery.

  10. Imaging Spectroscopy Techniques for Rapid Assessment of Geologic and Cryospheric Science Data from future Satellite Sensors

    Science.gov (United States)

    Calvin, W. M.; Hill, R.

    2016-12-01

    Several efforts are currently underway to develop and launch the next generation of imaging spectrometer systems on satellite platforms for a wide range of Earth Observation goals. Systems that include the reflected solar wavelength range up to 2.5 μm will be capable of detailed mapping of the composition of the Earth's surface. Sensors under development include EnMAP, HISUI, PRISMA, HERO, and HyspIRI. These systems are expected to be able to provide global data for insights and constraints on fundamental geological processes, natural and anthropogenic hazards, water, energy and mineral resource assessments. Coupled with the development of these sensors is the challenge of bringing a multi-channel user community (from Landsat, MODIS, and ASTER) into the rich science return available from imaging spectrometer systems. Most data end users will never be spectroscopy experts so that making the derived science products accessible to a wide user community is imperative. Simple band parameterizations have been developed for the CRISM instrument at Mars, including mafic and alteration minerals, frost and volatile ice indices. These products enhance and augment the use of that data set by broader group of scientists. Summary products for terrestrial geologic and water resource applications would help build a wider user base for future satellite systems, and rapidly key spectral experts to important regions for detailed spectral mapping. Summary products take advantage of imaging spectroscopy's narrow spectral channels with band depth calculations in addition to band ratios that are commonly used by multi-channel systems (e.g. NDVI, NDWI, NDSI). We are testing summary products for Earth geologic and snow scenes over California using AVIRIS data at 18m/pixel. This has resulted in several algorithms for rapid mineral discrimination and mapping and data collects over the melting Sierra snowpack in spring 2016 are expected to generate algorithms for snow grain size and surface

  11. Uncertainty of soil reflectance retrieval from SPOT and RapidEye multispectral satellite images using a per-pixel bootstrapped empirical line atmospheric correction over an agricultural region

    Science.gov (United States)

    Vaudour, E.; Gilliot, J. M.; Bel, L.; Bréchet, L.; Hamiache, J.; Hadjar, D.; Lemonnier, Y.

    2014-02-01

    Many authors have reported the use of empirical line regression between field target sites and image pixels in order to perform atmospheric correction of multispectral images. However few studies were dedicated to the specific reflectance retrieval for cultivated bare soils from multispectral satellite images, from a large number (≥15) of bare field targets spread over a region. Even fewer were oriented towards additional field targets for validation and uncertainty assessment of reflectance error. This study aimed at assessing ELM validation accuracy and uncertainty for predicting topsoil reflectance over a wide area (221 km2) with contrasting soils and tillage practices using a set of six multispectral images at very high (supermode SPOT5, 2.5 m), high (RapidEye, 6.5 m) and medium (SPOT4, 20 m) spatial resolutions. For each image and each spectral band, linear regression (LR) models were constructed through a series of 1000 bootstrap datasets of training/validation samples generated amongst a total of about 30 field sites used as targets, the reflectance measurements of which were made between -6 days/+7 days around acquisition date. The achieved models had an average coefficient of variation of validation errors of ∼14%, which indicates that the composition of training field sites does influence performance results of ELM. However, according to median LR-models, our approach mostly resulted in accurate predictions with low standard errors of estimation around 1-2% reflectance, validation errors of 2-3% reflectance, low validation bias (March: in agricultural areas, images programmed during periods when most field tillage operations have resulted in smooth seedbed conditions (April in this study) are in favour of better performances of soil reflectance prediction. Nevertheless, directional effects appear to mainly and moderately affect the global performance of near-infrared and SWIR bands-models except for oblique viewing images (viewing angle > |20°|). The

  12. Générateur de timing local pour l'acquisition des transformateurs rapides (LEIR, LINAC 3, LINAC 2, Ligne d'injection PSB)

    CERN Document Server

    Schnell, J D

    2006-01-01

    Dans le cadre des acquisitions des transformateurs rapides des deux LINACS, de la ligne d'injection PSB et de la machine LEIR, un nouveau hardware a été mis en opération [1]. Celui-ci assure la digitalisation des signaux analogiques et aussi de certains signaux de timing devant cadrer la mesure. Pour ce faire des ADC SIS3300 (SIS3320) et des DPRAM 80408 sont mis en service. Ces unités nécéssitent pour leur fonctionnement des horloges et des timings qui normalement sont intégralement fournis par l'équipement standard CO, notamment des CTRV et autres TG8. Suite à des problèmes d'approvisionnement, il existe des cas où l'on ne dispose pas (du moins pour le court terme) de suffisemment de ressources standard pour pourvoir au timing mentionné plus haut. Le tiroir qui fait l'objet de la présente description assure, avec certaines limitations, la génération des timings et autres horloges utilisées par les DPRAM 80408 et les ADC SIS3300.

  13. Data acquisition and analysis of mammography images at the NSLS June--August 1995

    Energy Technology Data Exchange (ETDEWEB)

    Arfelli, F. [Brookhaven National Lab., Upton, NY (United States). National Synchrotron Light Source; Burns, C. [Univ. of North Carolina, Chapel Hill, NC (United States). Dept. of Radiology; Chapman, D. [Brookhaven National Lab., Upton, NY (United States). National Synchrotron Light Source]|[Illinois Inst. of Tech., Chicago, IL (United States)] [and others

    1995-12-31

    At Brookhaven National Laboratory mammography experiments are being carried out at the X27C R and D beamline of the National Synchrotron Light Source using a monochromatic x-ray beam in order to explore the potential of monoenergetic photons for mammographic imaging. In two different periods of beamtime the authors have performed preliminary studies of mammographic imaging using a monochromatic synchrotron radiation source. They used both phantom objects and real tissue samples. Qualitative studies with the contrast-detail phantom show good agreement when compared with the theoretical contrast. As expected, the contrast is higher if the energy is lower. The results show an improved contrast with energies 18 keV and lower compared to images obtained from conventional polyenergetic x-ray imaging systems. The results also show that for similar imaging conditions the monoenergetic mean glandular dose is less than that from polyenergetic sources. This is due both to the increased sensitivity of the image plate detectors and to actual reductions of dose for truly monochromatic beams.

  14. Acquisition of multi-spectral flash image using optimization method via weight map

    Science.gov (United States)

    Choi, Bong-Seok; Kim, Dae-Chul; Kwon, Oh-Seol; Ha, Yeong-Ho

    2013-02-01

    To acquire images in low-light environments, it is usually necessary to adopt long exposure times or to resort to flashes. Flashes, however, often induce color distortion, cause the red-eye effect and can be disturbing to the subjects. On the other hand, long-exposure shots are susceptible to subject-motion, as well as motion-blur due to camera shake when performed with a hand-held camera. A recently introduced technique to overcome the limitations of the traditional lowlight photography is the use of the multi-spectral flash. Multi-spectral flash images are a combination of UV/IR and visible spectrum information. The general idea is to retrieve the details from the UV/IR spectrum and the color from the visible spectrum. Multi-spectral flash images, however, are themselves subject to color distortion and noise. In this work, a method of computing multi-spectral flash images so as to reduce the noise and to improve the color accuracy is presented. The proposed method is a previously seen optimization method, improved by introducing a weight map used to discriminate the uniform regions from the detail regions. The optimization target function takes into account the output likelihood with respect to the ambient light image, the sparsity of image gradients, and the spectral constraints for the IR-red and UV-blue channels. The performance of the proposed method was objectively evaluated using longexposure shots as references.

  15. Rapid comprehensive evaluation of luminography and hemodynamic function with 3D radially undersampled phase contrast imaging MRI.

    Science.gov (United States)

    Johnson, Kevin M; Francois, Chris; Lum, Darren; Bley, Thorsten A; Nett, Elisabeth; Landgraf, Benjamin; Reeder, Scott B; Grist, Thomas M; Wieben, Oliver

    2009-01-01

    Quantitative flow measurements with volumetric coverage and three directional flow encoding are technically feasible with magnetic resonance imaging yet prohibitively long in clinical settings. Data reconstruction from three dimensional angular undersampled MR acquisitions allows for dramatic reductions in scan time with tolerable imaging artifacts in many clinical applications. This approach provides high spatial resolution suitable for hemodynamic analysis in smaller vessels such as the renal artery, thereby providing additional crucial diagnostic information in a non invasive fashion. In an animal model, transstenotic pressure gradient measurements obtained with the novel acquisition scheme compared favorably with invasive intra arterial measurements (r=0.977; 95% CI: 0.931-0.998; p<0.001). In addition, human studies demonstrate the suitability of the technique for lumen measurements as an alternative for contrast enhanced MR Angiography and the associated risks with the use of an external contrast agent in certain patient populations.

  16. Visual processing in rapid-chase systems: Image processing, attention, and awareness

    Directory of Open Access Journals (Sweden)

    Thomas eSchmidt

    2011-07-01

    Full Text Available Visual stimuli can be classified so rapidly that their analysis may be based on a single sweep of feedforward processing through the visuomotor system. Behavioral criteria for feedforward processing can be evaluated in response priming tasks where speeded pointing or keypress responses are performed towards target stimuli which are preceded by prime stimuli. We apply this method to several classes of complex stimuli. 1 When participants classify natural images into animals or non-animals, the time course of their pointing responses indicates that prime and target signals remain strictly sequential throughout all processing stages, meeting stringent behavioral criteria for feedforward processing (rapid-chase criteria. 2 Such priming effects are boosted by selective visual attention for positions, shapes, and colors, in a way consistent with bottom-up enhancement of visuomotor processing, even when primes cannot be consciously identified. 3 Speeded processing of phobic images is observed in participants specifically fearful of spiders or snakes, suggesting enhancement of feedforward processing by long-term perceptual learning. 4 When the perceived brightness of primes in complex displays is altered by means of illumination or transparency illusions, priming effects in speeded keypress responses can systematically contradict subjective brightness judgments, such that one prime appears brighter than the other but activates motor responses as if it was darker. We propose that response priming captures the output of the first feedforward pass of visual signals through the visuomotor system, and that this output lacks some characteristic features of more elaborate, recurrent processing. This way, visuomotor measures may become dissociated from several aspects of conscious vision. We argue that "fast" visuomotor measures predominantly driven by feedforward processing should supplement "slow" psychophysical measures predominantly based on visual

  17. Rapidly destructive arthrosis of the shoulder joints: radiographic, magnetic resonance imaging, and histopathologic findings.

    Science.gov (United States)

    Kekatpure, Aashay L; Sun, Ji-Ho; Sim, Gyeong-Bo; Chun, Jae-Myeung; Jeon, In-Ho

    2015-06-01

    Rapidly destructive arthrosis of the humeral head is a rare condition with an elusive pathophysiologic mechanism. In this study, radiographic and histopathologic findings were analyzed to determine the clinical characteristics of this rare condition. We retrospectively analyzed 189 patients who underwent total shoulder arthroplasty from January 2001 to August 2012. Among them, 9 patients showed a particular pattern of rapid collapse of the humeral head on plain radiography and magnetic resonance imaging (MRI) within 12 months from symptom onset. Patients with trauma, rheumatoid arthritis, steroid intake, neurologic osteoarthropathy, osteonecrosis, renal osteoarthropathy, or gout were excluded. All patients were women, with a mean age of 72.0 years (range, 63-85 years). The right side was involved in 7 cases and the left in 2 cases. The mean duration of humeral head collapse was 5.6 months (range, 2-11 months) from the onset of shoulder pain. Plain radiographs of all patients showed a unique pattern of humeral head flattening, which appeared like a clean surgical cut with bone debris around the humeral head. MRI findings revealed significant joint effusion and bone marrow edema in the humeral head, without involvement of the glenoid. Pathologic findings showed both fragmentation and regeneration of bone matrix, representing fracture healing. The important features of rapidly destructive shoulder arthrosis are unique flattened humeral head collapse with MRI showing massive joint effusion and bone marrow edema in the remnant humeral head. This condition should be considered in the differential diagnosis of elderly women with insidious shoulder pain. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  18. Rapid microwave-assisted synthesis of dextran-coated iron oxide nanoparticles for magnetic resonance imaging

    Science.gov (United States)

    Osborne, Elizabeth A.; Atkins, Tonya M.; Gilbert, Dustin A.; Kauzlarich, Susan M.; Liu, Kai; Louie, Angelique Y.

    2012-06-01

    Currently, magnetic iron oxide nanoparticles are the only nanosized magnetic resonance imaging (MRI) contrast agents approved for clinical use, yet commercial manufacturing of these agents has been limited or discontinued. Though there is still widespread demand for these particles both for clinical use and research, they are difficult to obtain commercially, and complicated syntheses make in-house preparation unfeasible for most biological research labs or clinics. To make commercial production viable and increase accessibility of these products, it is crucial to develop simple, rapid and reproducible preparations of biocompatible iron oxide nanoparticles. Here, we report a rapid, straightforward microwave-assisted synthesis of superparamagnetic dextran-coated iron oxide nanoparticles. The nanoparticles were produced in two hydrodynamic sizes with differing core morphologies by varying the synthetic method as either a two-step or single-step process. A striking benefit of these methods is the ability to obtain swift and consistent results without the necessity for air-, pH- or temperature-sensitive techniques; therefore, reaction times and complex manufacturing processes are greatly reduced as compared to conventional synthetic methods. This is a great benefit for cost-effective translation to commercial production. The nanoparticles are found to be superparamagnetic and exhibit properties consistent for use in MRI. In addition, the dextran coating imparts the water solubility and biocompatibility necessary for in vivo utilization.

  19. High-speed multiframe dynamic transmission electron microscope image acquisition system with arbitrary timing

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Bryan W.; DeHope, William J.; Huete, Glenn; LaGrange, Thomas B.; Shuttlesworth, Richard M.

    2015-10-20

    An electron microscope is disclosed which has a laser-driven photocathode and an arbitrary waveform generator (AWG) laser system ("laser"). The laser produces a train of temporally-shaped laser pulses of a predefined pulse duration and waveform, and directs the laser pulses to the laser-driven photocathode to produce a train of electron pulses. An image sensor is used along with a deflector subsystem. The deflector subsystem is arranged downstream of the target but upstream of the image sensor, and has two pairs of plates arranged perpendicular to one another. A control system controls the laser and a plurality of switching components synchronized with the laser, to independently control excitation of each one of the deflector plates. This allows each electron pulse to be directed to a different portion of the image sensor, as well as to be provided with an independently set duration and independently set inter-pulse spacings.

  20. High-speed multiframe dynamic transmission electron microscope image acquisition system with arbitrary timing

    Science.gov (United States)

    Reed, Bryan W.; Dehope, William J; Huete, Glenn; LaGrange, Thomas B.; Shuttlesworth, Richard M

    2016-06-21

    An electron microscope is disclosed which has a laser-driven photocathode and an arbitrary waveform generator (AWG) laser system ("laser"). The laser produces a train of temporally-shaped laser pulses of a predefined pulse duration and waveform, and directs the laser pulses to the laser-driven photocathode to produce a train of electron pulses. An image sensor is used along with a deflector subsystem. The deflector subsystem is arranged downstream of the target but upstream of the image sensor, and has two pairs of plates arranged perpendicular to one another. A control system controls the laser and a plurality of switching components synchronized with the laser, to independently control excitation of each one of the deflector plates. This allows each electron pulse to be directed to a different portion of the image sensor, as well as to be provided with an independently set duration and independently set inter-pulse spacings.

  1. High-speed multi-frame dynamic transmission electron microscope image acquisition system with arbitrary timing

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Bryan W.; DeHope, William J.; Huete, Glenn; LaGrange, Thomas B.; Shuttlesworth, Richard M.

    2016-02-23

    An electron microscope is disclosed which has a laser-driven photocathode and an arbitrary waveform generator (AWG) laser system ("laser"). The laser produces a train of temporally-shaped laser pulses each being of a programmable pulse duration, and directs the laser pulses to the laser-driven photocathode to produce a train of electron pulses. An image sensor is used along with a deflector subsystem. The deflector subsystem is arranged downstream of the target but upstream of the image sensor, and has a plurality of plates. A control system having a digital sequencer controls the laser and a plurality of switching components, synchronized with the laser, to independently control excitation of each one of the deflector plates. This allows each electron pulse to be directed to a different portion of the image sensor, as well as to enable programmable pulse durations and programmable inter-pulse spacings.

  2. Registration-based regional lung mechanical analysis: retrospectively reconstructed dynamic imaging versus static breath-hold image acquisition

    Science.gov (United States)

    Ding, Kai; Cao, Kunlin; Christensen, Gary E.; Hoffman, Eric A.; Reinhardt, Joseph M.

    2009-02-01

    The lungs undergo expansion and contraction during the respiratory cycle. Since many disease or injury conditions are associated with the biomechanical or material property changes that can alter lung function, there is a great interest in measuring regional lung ventilation and regional mechanical changes. We describe a technique that uses multiple respiratory-gated CT images and non-rigid 3D image registration to make local estimates of lung tissue expansion. The degree of regional lung expansion is measured using the Jacobian (a function of local partial derivatives) of the registration displacement field. We compare the ventral-dorsal patterns of lung expansion estimated in both retrospectively reconstructed dynamic scans and static breath-hold scans to a xenon CT based measure of specific ventilation and a semi-automatic reference standard in four anesthetized sheep studied in the supine orientation. The regional lung expansion estimated by 3D image registration of images acquired at 50% and 75% phase points of the inspiratory portion of the respiratory cycle and 20 cm H2O and 25 cm H2O airway pressures gave the best match between the average Jacobian and the xenon CT specific ventilation respectively (linear regression, average r2 = 0.85 and r2 = 0.84). The registration accuracy assessed by 200 semi-automatically matched landmarks in both the dynamic and static scans show landmark error on the order of 2 mm.

  3. Rapid and noncontact photoacoustic tomography imaging system using an interferometer with high-speed phase modulation technique

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jun [School of Physics and Telecom Engineering, South China Normal University, Guangzhou 510006 (China); Tang, Zhilie; Wu, Yongbo [School of Physics and Telecom Engineering, South China Normal University, Guangzhou 510006 (China); GuangDong Province Key Laboratory of Quantum Engineering and Quantum Materials, South China Normal University, IMOT, Guangzhou 510006 (China); Wang, Yi [School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004 (China)

    2015-04-15

    We designed, fabricated, and tested a rapid and noncontact photoacoustic tomography (PAT) imaging system using a low-coherence interferometer with high-speed phase modulation technique. Such a rapid and noncontact probing system can greatly decrease the time of imaging. The proposed PAT imaging system is experimentally verified by capturing images of a simulated tissue sample and the blood vessels within the ear flap of a mouse (pinna) in vivo. The axial and lateral resolutions of the system are evaluated at 45 and ∼15 μm, respectively. The imaging depth of the system is 1 mm in a special phantom. Our results show that the proposed system opens a promising way to realize noncontact, real-time PAT.

  4. Cardiac imaging with multi-sector data acquisition in volumetric CT: variation of effective temporal resolution and its potential clinical consequences

    Science.gov (United States)

    Tang, Xiangyang; Hsieh, Jiang; Taha, Basel H.; Vass, Melissa L.; Seamans, John L.; Okerlund, Darin R.

    2009-02-01

    With increasing longitudinal detector dimension available in diagnostic volumetric CT, step-and-shoot scan is becoming popular for cardiac imaging. In comparison to helical scan, step-and-shoot scan decouples patient table movement from cardiac gating/triggering, which facilitates the cardiac imaging via multi-sector data acquisition, as well as the administration of inter-cycle heart beat variation (arrhythmia) and radiation dose efficiency. Ideally, a multi-sector data acquisition can improve temporal resolution at a factor the same as the number of sectors (best scenario). In reality, however, the effective temporal resolution is jointly determined by gantry rotation speed and patient heart beat rate, which may significantly lower than the ideal or no improvement (worst scenario). Hence, it is clinically relevant to investigate the behavior of effective temporal resolution in cardiac imaging with multi-sector data acquisition. In this study, a 5-second cine scan of a porcine heart, which cascades 6 porcine cardiac cycles, is acquired. In addition to theoretical analysis and motion phantom study, the clinical consequences due to the effective temporal resolution variation are evaluated qualitative or quantitatively. By employing a 2-sector image reconstruction strategy, a total of 15 (the permutation of P(6, 2)) cases between the best and worst scenarios are studied, providing informative guidance for the design and optimization of CT cardiac imaging in volumetric CT with multi-sector data acquisition.

  5. Rapid implementation of image processing onto FPGA using modular DSP C6201 VHDL model

    Science.gov (United States)

    Brost, V.; Yang, F.; Paindavoine, M.; Liu, X. J.

    2007-01-01

    Recent FPGA chips, with their large capacity memory and reconfigurability potential, have opened new frontiers for rapid prototyping of embedded systems. With the advent of high density FPGAs it is now feasible to implement a high-performance VLIW processor core in an FPGA. We describe research results of enabling the DSP TMS320 C6201 model for real-time image processing applications, by exploiting FPGA technology. The goals are, firstly, to keep the flexibility of DSP in order to shorten the development cycle, and secondly, to use powerful available resources on FPGA to a maximum in order to increase real-time performance. We present a modular DSP C6201 VHDL model which contains only the bare minimum number of instruction sets, or modules, necessary for each target application. This allows an optimal implementation on the FPGA. Some common algorithms of image processing were created and validated on an FPGA VirtexII-2000 multimedia board using the proposed application development cycle. Our results demonstrate that an algorithm can easily be, in an optimal manner, specified and then automatically converted to VHDL language and implemented on an FPGA device with system level software.

  6. Rapid in situ biosynthesis of gold nanoparticles in living platelets for multimodal biomedical imaging.

    Science.gov (United States)

    Jin, Juan; Liu, Taotao; Li, Mingxi; Yuan, Chuxiao; Liu, Yang; Tang, Jian; Feng, Zhenqiang; Zhou, Yue; Yang, Fang; Gu, Ning

    2018-01-10

    Inspired by the nature, the biomimetic nanomaterial design strategies have attracted great interest because the bioinspired nanoplatforms may enhance the functionality of current nanoparticles. Especially, the cell membrane-derived nanoparticles can more effectively navigate and interact with the complex biological microenvironment. In this study, we have explored a novel strategy to rapidly in situ biosynthesize gold nanoparticles (GNPs) in living platelets with the help of ultrasound energy. Firstly, under the ultrasound exposure, the biocompatible chloroauric acid salts (HAuCl 4 ) can be enhanced to permeate into the platelet cytoplasm. Then, by the assist of reducing agent (NaBH 4 and sodium citrate) and platelet enzyme, GNPs were fast in situ synthesized in intra-platelets. The biosynthesized GNPs had a size of about 5 nm and were uniformly distributed in the cytoplasm. Atomic absorption spectrometry (AAS) showed the synthesized amount of Au is (12.7 ± 2.4) × 10 -3  pg per one platelet. The GNPs in platelets can produce Raman enhancement effect and further be probed for both dark-field microscopy (DFM)-based imaging and computed tomography (CT) imaging. Moreover, the platelets were not activated and remained aggregation bioactivity when intra-platelet GNPs synthesis. Therefore, such mimicking GNPs-platelets with in situ GNPs components remain inherent platelet bioactivity will find potential theranostic implications with unique GNPs properties. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Nosocomial rapidly growing mycobacterial infections following laparoscopic surgery: CT imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Volpato, Richard [Cassiano Antonio de Moraes University Hospital, Department of Diagnostic Radiology, Vitoria, ES (Brazil); Campi de Castro, Claudio [University of Sao Paulo Medical School, Department of Radiology, Cerqueira Cesar, Sao Paulo (Brazil); Hadad, David Jamil [Cassiano Antonio de Moraes University Hospital, Nucleo de Doencas Infecciosas, Department of Internal Medicine, Vitoria, ES (Brazil); Silva Souza Ribeiro, Flavya da [Laboratorio de Patologia PAT, Department of Diagnostic Radiology, Unit 1473, Vitoria, ES (Brazil); Filho, Ezequiel Leal [UNIMED Diagnostico, Department of Diagnostic Radiology, Unit 1473, Vitoria, ES (Brazil); Marcal, Leonardo P. [The University of Texas M D Anderson Cancer Center, Department of Diagnostic Radiology, Unit 1473, Houston, TX (United States)

    2015-09-15

    To identify the distribution and frequency of computed tomography (CT) findings in patients with nosocomial rapidly growing mycobacterial (RGM) infection after laparoscopic surgery. A descriptive retrospective study in patients with RGM infection after laparoscopic surgery who underwent CT imaging prior to initiation of therapy. The images were analyzed by two radiologists in consensus, who evaluated the skin/subcutaneous tissues, the abdominal wall, and intraperitoneal region separately. The patterns of involvement were tabulated as: densification, collections, nodules (≥1.0 cm), small nodules (<1.0 cm), pseudocavitated nodules, and small pseudocavitated nodules. Twenty-six patients met the established criteria. The subcutaneous findings were: densification (88.5 %), small nodules (61.5 %), small pseudocavitated nodules (23.1 %), nodules (38.5 %), pseudocavitated nodules (15.4 %), and collections (26.9 %). The findings in the abdominal wall were: densification (61.5 %), pseudocavitated nodules (3.8 %), and collections (15.4 %). The intraperitoneal findings were: densification (46.1 %), small nodules (42.3 %), nodules (15.4 %), and collections (11.5 %). Subcutaneous CT findings in descending order of frequency were: densification, small nodules, nodules, small pseudocavitated nodules, pseudocavitated nodules, and collections. The musculo-fascial plane CT findings were: densification, collections, and pseudocavitated nodules. The intraperitoneal CT findings were: densification, small nodules, nodules, and collections. (orig.)

  8. Teaching the Dance Class: Strategies to Enhance Skill Acquisition, Mastery and Positive Self-Image

    Science.gov (United States)

    Mainwaring, Lynda M.; Krasnow, Donna H.

    2010-01-01

    Effective teaching of dance skills is informed by a variety of theoretical frameworks and individual teaching and learning styles. The purpose of this paper is to present practical teaching strategies that enhance the mastery of skills and promote self-esteem, self-efficacy, and positive self-image. The predominant thinking and primary research…

  9. Ultrashort echo time imaging with acquisition trajectory mapping for correction of gradient imperfections

    Czech Academy of Sciences Publication Activity Database

    Latta, P.; Starčuk jr., Zenon; Gruwel, M. L. H.; Tománek, B.

    2015-01-01

    Roč. 28, S1 (2015), S102 ISSN 0968-5243. [ESMRMB 2015. Annual Scientific Meeting /32./. 01.09.2015-03.09.2015, Edinburgh] R&D Projects: GA ČR(CZ) GA15-12607S Institutional support: RVO:68081731 Keywords : UTE MRI * radial sampling * image reconstructio Subject RIV: FS - Medical Facilities ; Equipment

  10. Design and characterization of a digital image acquisition system for whole-specimen breast histopathology

    Science.gov (United States)

    Clarke, Gina M.; Peressotti, Chris; Mawdsley, Gordon E.; Yaffe, Martin J.

    2006-10-01

    We have developed a digital histopathology imaging system capable of producing a three-dimensional (3D) representation of histopathology from an entire lumpectomy specimen. The system has the potential to improve the accuracy of surgical margin assessment in the treatment of breast cancer by providing finer sampling and 3D visualization. A scanning light microscope was modified to allow digital photomicrography of a stack of large (up to 120 × 170 mm2) histology slides cut serially through the entire specimen. The images are registered and displayed in 2D and 3D. The design of the system, which reduces or eliminates the appearance of 'tiling' and 'seam' artefacts inherent in the scanning method, is described and its resolution, contrast/noise and coverage properties are characterized through measurements of the modulation transfer function (MTF), depth of field (DOF) and signal difference to noise ratio (SDNR). The imaging task requires a lateral resolution of 5 µm, an SDNR of 5 between relevant features, 'tiling artefact' at a level below the detectability threshold of the eye, and 'seam artefact' of less than 5-10 µm. The tests demonstrate that the system is largely adequate for the imaging task, although further optimizations are required to reduce the degradation of coverage incurred by seam artefact.

  11. Design and characterization of a digital image acquisition system for whole-specimen breast histopathology

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, Gina M [Imaging Research Program, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5 (Canada); Peressotti, Chris [Imaging Research Program, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5 (Canada); Mawdsley, Gordon E [Imaging Research Program, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5 (Canada); Yaffe, Martin J [Imaging Research Program, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5 (Canada)

    2006-10-21

    We have developed a digital histopathology imaging system capable of producing a three-dimensional (3D) representation of histopathology from an entire lumpectomy specimen. The system has the potential to improve the accuracy of surgical margin assessment in the treatment of breast cancer by providing finer sampling and 3D visualization. A scanning light microscope was modified to allow digital photomicrography of a stack of large (up to 120 x 170 mm{sup 2}) histology slides cut serially through the entire specimen. The images are registered and displayed in 2D and 3D. The design of the system, which reduces or eliminates the appearance of 'tiling' and 'seam' artefacts inherent in the scanning method, is described and its resolution, contrast/noise and coverage properties are characterized through measurements of the modulation transfer function (MTF), depth of field (DOF) and signal difference to noise ratio (SDNR). The imaging task requires a lateral resolution of 5 {mu}m, an SDNR of 5 between relevant features, 'tiling artefact' at a level below the detectability threshold of the eye, and 'seam artefact' of less than 5-10 {mu}m. The tests demonstrate that the system is largely adequate for the imaging task, although further optimizations are required to reduce the degradation of coverage incurred by seam artefact.

  12. Recovering the dynamics of root growth and development using novel image acquisition and analysis methods.

    Science.gov (United States)

    Wells, Darren M; French, Andrew P; Naeem, Asad; Ishaq, Omer; Traini, Richard; Hijazi, Hussein I; Hijazi, Hussein; Bennett, Malcolm J; Pridmore, Tony P

    2012-06-05

    Roots are highly responsive to environmental signals encountered in the rhizosphere, such as nutrients, mechanical resistance and gravity. As a result, root growth and development is very plastic. If this complex and vital process is to be understood, methods and tools are required to capture the dynamics of root responses. Tools are needed which are high-throughput, supporting large-scale experimental work, and provide accurate, high-resolution, quantitative data. We describe and demonstrate the efficacy of the high-throughput and high-resolution root imaging systems recently developed within the Centre for Plant Integrative Biology (CPIB). This toolset includes (i) robotic imaging hardware to generate time-lapse datasets from standard cameras under infrared illumination and (ii) automated image analysis methods and software to extract quantitative information about root growth and development both from these images and via high-resolution light microscopy. These methods are demonstrated using data gathered during an experimental study of the gravitropic response of Arabidopsis thaliana.

  13. Clinical Evaluation of PET Image Quality as a Function of Acquisition Time in a New TOF-PET/MRI Compared to TOF-PET/CT--Initial Results.

    Science.gov (United States)

    Zeimpekis, Konstantinos G; Barbosa, Felipe; Hüllner, Martin; ter Voert, Edwin; Davison, Helen; Veit-Haibach, Patrick; Delso, Gaspar

    2015-10-01

    The purpose of this study was to compare only the performance of the PET component between a TOF-PET/CT (henceforth noted as PET/CT) scanner and an integrated TOF-PET/MRI (henceforth noted as PET/MRI) scanner concerning image quality parameters and quantification in terms of standardized uptake value (SUV) as a function of acquisition time (a surrogate of dose). The CT and MR image quality were not assessed, and that is beyond the scope of this study. Five brain and five whole-body patients were included in the study. The PET/CT scan was used as a reference and the PET/MRI acquisition time was consecutively adjusted, taking into account the decay between the scans in order to expose both systems to the same amount of the emitted signal. The acquisition times were then retrospectively reduced to assess the performance of the PET/MRI for lower count rates. Image quality, image sharpness, artifacts, and noise were evaluated. SUV measurements were taken in the liver and in the white matter to compare quantification. Quantitative evaluation showed strong correlation between PET/CT and PET/MRI brain SUVs. Liver correlation was good, however, with lower uptake estimation in PET/MRI, partially justified by bio-redistribution. The clinical evaluation showed that PET/MRI offers higher image quality and sharpness with lower levels of noise and artifacts compared to PET/CT with reduced acquisition times for whole-body scans while for brain scans there is no significant difference. The TOF-PET/MRI showed higher image quality compared to TOF-PET/CT as tested with reduced imaging times. However, this result accounts mainly for body imaging, while no significant differences were found in brain imaging.

  14. Simultaneous acquisition of magnetic resonance spectroscopy (MRS) data and positron emission tomography (PET) images with a prototype MR-compatible, small animal PET imager

    Energy Technology Data Exchange (ETDEWEB)

    Raylman, Raymond R; Majewski, Stan; Velan, S Sendhil; Lemieux, Susan; Kross, Brian; Popov, Vladimir; Smith, Mark F; Weisenberger, Andrew G

    2007-06-01

    Multi-modality imaging (such as PET-CT) is rapidly becoming a valuable tool in the diagnosis of disease and in the development of new drugs. Functional images produced with PET, fused with anatomical images created by MRI, allow the correlation of form with function. Perhaps more exciting than the combination of anatomical MRI with PET, is the melding of PET with MR spectroscopy (MRS). Thus, two aspects of physiology could be combined in novel ways to produce new insights into the physiology of normal and pathological processes. Our team is developing a system to acquire MRI images and MRS spectra, and PET images contemporaneously. The prototype MR-compatible PET system consists of two opposed detector heads (appropriate in size for small animal imaging), operating in coincidence mode with an active field-of-view of ∼14 cm in diameter. Each detector consists of an array of LSO detector elements coupled through a 2-m long fiber optic light guide to a single position-sensitive photomultiplier tube. The use of light guides allows these magnetic field-sensitive elements of the PET imager to be positioned outside the strong magnetic field of our 3T MRI scanner. The PET scanner imager was integrated with a 12-cm diameter, 12-leg custom, birdcage coil. Simultaneous MRS spectra and PET images were successfully acquired from a multi-modality phantom consisting of a sphere filled with 17 brain relevant substances and a positron-emitting radionuclide. There were no significant changes in MRI or PET scanner performance when both were present in the MRI magnet bore. This successful initial test demonstrates the potential for using such a multi-modality to obtain complementary MRS and PET data.

  15. Acquisition of quantitative physiological data and computerized image reconstruction using a single scan TV system

    Science.gov (United States)

    Baily, N. A.

    1976-01-01

    A single-scan radiography system has been interfaced to a minicomputer, and the combined system has been used with a variety of fluoroscopic systems and image intensifiers available in clinical facilities. The system's response range is analyzed, and several applications are described. These include determination of the gray scale for typical X-ray-fluoroscopic-television chains, measurement of gallstone volume in patients, localization of markers or other small anatomical features, determinations of organ areas and volumes, computer reconstruction of tomographic sections of organs in motion, and computer reconstruction of transverse axial body sections from fluoroscopic images. It is concluded that this type of system combined with a minimum of statistical processing shows excellent capabilities for delineating small changes in differential X-ray attenuation.

  16. A low-cost multielectrode system for data acquisition enabling real-time closed-loop processing with rapid recovery from stimulation artifacts

    Directory of Open Access Journals (Sweden)

    John D Rolston

    2009-07-01

    Full Text Available Commercially available data acquisition systems for multielectrode recording from freely moving animals are expensive, often rely on proprietary software, and do not provide detailed, modifiable circuit schematics. When used in conjunction with electrical stimulation, they are prone to prolonged, saturating stimulation artifacts that prevent the recording of short-latency evoked responses. Yet electrical stimulation is integral to many experimental designs, and critical for emerging brain-computer interfacing and neuroprosthetic applications. To address these issues, we developed an easy-to-use, modifiable, and inexpensive system for multielectrode neural recording and stimulation. Setup costs are less than US$10,000 for 64 channels, an order of magnitude lower than comparable commercial systems. Unlike commercial equipment, the system recovers rapidly from stimulation and allows short-latency action potentials (<1 ms post-stimulus to be detected, facilitating closed-loop applications and exposing neural activity that would otherwise remain hidden. To illustrate this capability, evoked activity from microstimulation of the rodent hippocampus is presented. The system is modular, in banks of 16 channels, and flexible in usage: while primarily designed for in vivo use, it can be combined with commercial preamplifiers to record from in vitro multielectrode arrays. The system’s open-source control software, NeuroRighter, is implemented in C#, with an easy-to-use graphical interface. As C# functions in a managed code environment, which may impact performance, analysis was conducted to ensure comparable speed to C++ for this application. Hardware schematics, layout files, and software are freely available. Since maintaining wired headstage connections with freely moving animals is difficult, we describe a new method of electrode-headstage coupling using neodymium magnets.

  17. Quantitative Functional Imaging Using Dynamic Positron Computed Tomography and Rapid Parameter Estimation Techniques

    Science.gov (United States)

    Koeppe, Robert Allen

    Positron computed tomography (PCT) is a diagnostic imaging technique that provides both three dimensional imaging capability and quantitative measurements of local tissue radioactivity concentrations in vivo. This allows the development of non-invasive methods that employ the principles of tracer kinetics for determining physiological properties such as mass specific blood flow, tissue pH, and rates of substrate transport or utilization. A physiologically based, two-compartment tracer kinetic model was derived to mathematically describe the exchange of a radioindicator between blood and tissue. The model was adapted for use with dynamic sequences of data acquired with a positron tomograph. Rapid estimation techniques were implemented to produce functional images of the model parameters by analyzing each individual pixel sequence of the image data. A detailed analysis of the performance characteristics of three different parameter estimation schemes was performed. The analysis included examination of errors caused by statistical uncertainties in the measured data, errors in the timing of the data, and errors caused by violation of various assumptions of the tracer kinetic model. Two specific radioindicators were investigated. ('18)F -fluoromethane, an inert freely diffusible gas, was used for local quantitative determinations of both cerebral blood flow and tissue:blood partition coefficient. A method was developed that did not require direct sampling of arterial blood for the absolute scaling of flow values. The arterial input concentration time course was obtained by assuming that the alveolar or end-tidal expired breath radioactivity concentration is proportional to the arterial blood concentration. The scale of the input function was obtained from a series of venous blood concentration measurements. The method of absolute scaling using venous samples was validated in four studies, performed on normal volunteers, in which directly measured arterial concentrations

  18. QR-on-a-chip: a computer-recognizable micro-pattern engraved microfluidic device for high-throughput image acquisition.

    Science.gov (United States)

    Yun, Kyungwon; Lee, Hyunjae; Bang, Hyunwoo; Jeon, Noo Li

    2016-02-21

    This study proposes a novel way to achieve high-throughput image acquisition based on a computer-recognizable micro-pattern implemented on a microfluidic device. We integrated the QR code, a two-dimensional barcode system, onto the microfluidic device to simplify imaging of multiple ROIs (regions of interest). A standard QR code pattern was modified to arrays of cylindrical structures of polydimethylsiloxane (PDMS). Utilizing the recognition of the micro-pattern, the proposed system enables: (1) device identification, which allows referencing additional information of the device, such as device imaging sequences or the ROIs and (2) composing a coordinate system for an arbitrarily located microfluidic device with respect to the stage. Based on these functionalities, the proposed method performs one-step high-throughput imaging for data acquisition in microfluidic devices without further manual exploration and locating of the desired ROIs. In our experience, the proposed method significantly reduced the time for the preparation of an acquisition. We expect that the method will innovatively improve the prototype device data acquisition and analysis.

  19. Interannual Change Detection of Mediterranean Seagrasses Using RapidEye Image Time Series

    Directory of Open Access Journals (Sweden)

    Dimosthenis Traganos

    2018-02-01

    Full Text Available Recent research studies have highlighted the decrease in the coverage of Mediterranean seagrasses due to mainly anthropogenic activities. The lack of data on the distribution of these significant aquatic plants complicates the quantification of their decreasing tendency. While Mediterranean seagrasses are declining, satellite remote sensing technology is growing at an unprecedented pace, resulting in a wealth of spaceborne image time series. Here, we exploit recent advances in high spatial resolution sensors and machine learning to study Mediterranean seagrasses. We process a multispectral RapidEye time series between 2011 and 2016 to detect interannual seagrass dynamics in 888 submerged hectares of the Thermaikos Gulf, NW Aegean Sea, Greece (eastern Mediterranean Sea. We assess the extent change of two Mediterranean seagrass species, the dominant Posidonia oceanica and Cymodocea nodosa, following atmospheric and analytical water column correction, as well as machine learning classification, using Random Forests, of the RapidEye time series. Prior corrections are necessary to untangle the initially weak signal of the submerged seagrass habitats from satellite imagery. The central results of this study show that P. oceanica seagrass area has declined by 4.1%, with a trend of −11.2 ha/yr, while C. nodosa seagrass area has increased by 17.7% with a trend of +18 ha/yr throughout the 5-year study period. Trends of change in spatial distribution of seagrasses in the Thermaikos Gulf site are in line with reported trends in the Mediterranean. Our presented methodology could be a time- and cost-effective method toward the quantitative ecological assessment of seagrass dynamics elsewhere in the future. From small meadows to whole coastlines, knowledge of aquatic plant dynamics could resolve decline or growth trends and accurately highlight key units for future restoration, management, and conservation.

  20. SU-F-T-626: Intracranial SRS Re-Treatment Without Acquisition of New CT Images

    Energy Technology Data Exchange (ETDEWEB)

    Wiant, D; Manning, M; Liu, H; Maurer, J; Hayes, T; Sintay, B [Cone Health Cancer Center, Greensboro, NC (United States)

    2016-06-15

    Purpose: Linear accelerator based stereotactic radiosurgery (SRS) for multiple intracranial lesions with frequent surveillance is becoming a popular treatment option. This strategy leads to retreatment with SRS as new lesions arise. Currently, each course of treatment uses magnetic resonance (MR) and computed tomography (CT) images for treatment planning. We propose that new MR images, with course 1 CT images, may be used for future treatment plans with negligible loss of dosimetric accuracy. Methods: Ten patients that received multiple courses of SRS were retrospectively reviewed. The treatment plans and contours from non-initial courses were copied to the initial CTs and recalculated. Doses metrics for the plans calculated on the initial CTs and later CTs were compared. All CT scans were acquired on a Philips CT scanner with a 600 mm field of view and 1 mm slice thickness (Philips Healthcare, Andover, MA). All targets were planned to 20 Gy and calculated in Eclipse V. 13.6 (Varian, Palo Alto, CA) using analytic anisotropic algorithm with 1 mm calculation grid. Results: Sixteen lesions were evaluated. The mean time between courses was 250 +/− 215 days (range 103–979). The mean target volume was 2.0 +/− 2.9 cc (range 0.1–10.1). The average difference in mean target dose between the two calculations was 0.2 +/− 0.3 Gy (range 0.0 – 1.0). The mean conformity index (CI) was 1.28 +/− 0.14 (range 1.07 – 1.82). The average difference in CI was 0.03 +/− 0.16 (range 0.00 – 0.44). Targets volumes < 0.5 cc showed the largest changes in both metrics. Conclusion: Continued treatment based on initial CT images is feasible. Dose calculation on the initial CT for future treatments provides reasonable dosimetric accuracy. Changes in dose metrics are largest for small volumes, and are likely dominated by partial volume effects in target definition.

  1. A case of timely satellite image acquisitions in support of coastal emergency environmental response management

    Science.gov (United States)

    Ramsey, Elijah W.; Werle, Dirk; Lu, Zhong; Rangoonwala, Amina; Suzuoki, Yukihiro

    2009-01-01

    The synergistic application of optical and radar satellite imagery improves emergency response and advance coastal monitoring from the realm of “opportunistic” to that of “strategic.” As illustrated by the Hurricane Ike example, synthetic aperture radar imaging capabilities are clearly applicable for emergency response operations, but they are also relevant to emergency environmental management. Integrated with optical monitoring, the nearly real-time availability of synthetic aperture radar provides superior consistency in status and trends monitoring and enhanced information concerning causal forces of change that are critical to coastal resource sustainability, including flooding extent, depth, and frequency.

  2. A Simple Aerial Photogrammetric Mapping System Overview and Image Acquisition Using Unmanned Aerial Vehicles (UAVs

    Directory of Open Access Journals (Sweden)

    Wenang Anurogo

    2017-06-01

    Full Text Available Aerial photogrammetry is one of the Alternative technologies for more detailed data, real time, fast and cheaper. Nowadays, many photogrammetric mapping methods have used UAV / unmanned drones or drones to retrieve and record data from an object in the earth. The application of drones in the field of geospatial science today is in great demand because of its relatively easy operation and relatively affordable cost compared to satellite systems especially high - resolution satellite imagery.  This research aims to determine the stage or overview of data retrieval process with DJI Phantom 4 (multi - rotor quad - copter drone with processing using third party software. This research also produces 2 - dimensional high resolution image data on the research area. Utilization of third party software (Agisoft PhotoScan making it easier to acquire and process aerial photogrammetric data. The results of aerial photogrammetric recording with a flying altitude of 70 meters obtained high resolution images with a spatial resolution of 2 inches / pixels.

  3. Target acquisition and tracking based on a priori knowledge and an image sensor

    Science.gov (United States)

    Fang, Zhonghua; Chen, Tao

    2002-07-01

    When intercepting and tracking low-observable point-source or highly maneuvering big targets, the electro-optical (E-O) system will meet a fatal problem that the target lost easily. No effective method intercepts it again according to the dispersed azimuth and elevation tracking data. First, the paper gives an intelligent ATP control system architecture based on the data mart. Then an automatic real-time control algorithm is proposed, which is found on linguistic cloud model and fuzzy logic techniques. The linguistic cloud model is used to translate a linguistic term of qualitative concept into its numerical representation, such that the ATP control system can take full advantage of a priori knowledge which is always presented in natural language to refine the results of sequence images processing. The fuzzy logic technique is adopted to associate these results to target's trajectories. The paper offers an automatic reacquisition and tracking method to solve the targets lost problem.

  4. Design of deep convolutional networks for prediction of image rapid serial visual presentation events.

    Science.gov (United States)

    Zijing Mao; Wan Xiang Yao; Yufe Huang

    2017-07-01

    We report in this paper an investigation of convolutional neural network (CNN) models for target prediction in time-locked image rapid serial visual presentation (RSVP) experiment. We investigated CNN models with 11 different designs of convolution filters in capturing spatial and temporal correlations in EEG data. We showed that for both within-subject and cross-subject predictions, the CNN models outperform the state-of-the-art algorithms: Bayesian linear discriminant analysis (BLDA) and xDAWN spatial filtering and achieved >6% improvement. Among the 11 different CNN models, the global spatial filter and our proposed region of interest (ROI) achieved best performance. We also implemented the deconvolution network to show how we can visualize from activated hidden units for target/nontarget events learned by the ROI-CNN. Our study suggests that deep learning is a powerful tool for RSVP target prediction and the proposed model is applicable for general EEG-based classifications in brain computer interaction research. The code of this project is available at https://github.com/ZijingMao/ROICNN.

  5. Rapid wide-field Mueller matrix polarimetry imaging based on four photoelastic modulators with no moving parts.

    Science.gov (United States)

    Alali, Sanaz; Gribble, Adam; Vitkin, I Alex

    2016-03-01

    A new polarimetry method is demonstrated to image the entire Mueller matrix of a turbid sample using four photoelastic modulators (PEMs) and a charge coupled device (CCD) camera, with no moving parts. Accurate wide-field imaging is enabled with a field-programmable gate array (FPGA) optical gating technique and an evolutionary algorithm (EA) that optimizes imaging times. This technique accurately and rapidly measured the Mueller matrices of air, polarization elements, and turbid phantoms. The system should prove advantageous for Mueller matrix analysis of turbid samples (e.g., biological tissues) over large fields of view, in less than a second.

  6. Facial acquisition by dynamic optical tracked laser imaging: a new approach.

    Science.gov (United States)

    Schwenzer-Zimmerer, K; Boerner, B-I; Schwenzer, N F; Müller, A A; Juergens, P; Ringenbach, A; Schkommodau, E; Zeilhofer, H-F

    2009-09-01

    Three-dimensional capture of the surface of soft tissue is a desirable support for documentation and therapy planning in plastic and reconstructive surgery concerning the complex anatomy of the face, particularly cleft lip and palate (CLP). Different scanning systems are used for capturing facial surfaces. These systems are mostly based on a static linear measuring arrangement. Established systems work on the basis of coded white light or linear laser triangulation and digital stereophotogrammetric approaches. Shadowing effects occur with these devices. These effects may be avoided by a radical new approach first used in automotive industries that employs a mobile, flexible handheld laser scanner with simultaneous registration by optical tracking. The aim of this study was to assess the suitability of this scanner for surgical procedures on the human face in operating theatre. Five babies aged about 3 months with cleft deformities (one CLP, one bilateral CLP, three isolated cleft lips) were captured directly: twice preoperatively, twice postoperatively and twice after 7 days. An industrial standard specimen and two plaster cast masks of CLP babies were taken and subsequently measured to assess reliability and validity of the device. Masks were measured to reflect the complex surface of the cleft deformity. Data evaluation was done with respect to completeness of the data sets, as well as reliability and validity of the system. Missing data caused by shadowing could be avoided in all images. Even complex areas with undercuts could be reproduced completely and precisely with an accuracy in the sub-millimetre range.

  7. Front-end electronics and data acquisition system for imaging atmospheric Cherenkov telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y.T., E-mail: chenytao@ynu.edu.cn [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Yunnan University, 650091 Kunming (China); La Taille, C. de [OMEGA (UMS 3605) - IN2P3/CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Suomijärvi, T. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Cao, Z. [Institute of High Energy Physics, 100049 Beijing (China); Deligny, O. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Dulucq, F. [OMEGA (UMS 3605) - IN2P3/CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Ge, M.M. [Yunnan University, 650091 Kunming (China); Lhenry-Yvon, I. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Martin-Chassard, G. [OMEGA (UMS 3605) - IN2P3/CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Nguyen Trung, T.; Wanlin, E. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Xiao, G.; Yin, L.Q. [Institute of High Energy Physics, 100049 Beijing (China); Yun Ky, B. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Zhang, L. [Yunnan University, 650091 Kunming (China); Zhang, H.Y. [Tsinghua University, 100084 Beijing (China); Zhang, S.S.; Zhu, Z. [Institute of High Energy Physics, 100049 Beijing (China)

    2015-09-21

    In this paper, a front-end electronics based on an application-specific integrated circuit (ASIC) is presented for the future imaging atmospheric Cherenkov telescopes (IACTs). To achieve this purpose, a 16-channel ASIC chip, PARISROC 2 (Photomultiplier ARray Integrated in SiGe ReadOut Chip) is used in the analog signal processing and digitization. The digitized results are sent to the server by a user-defined User Datagram Protocol/Internet Protocol (UDP/IP) hardcore engine through Ethernet that is managed by a FPGA. A prototype electronics fulfilling the requirements of the Wide Field of View Cherenkov Telescope Array (WFCTA) of the Large High Altitude Air Shower Observatory (LHAASO) project has been designed, fabricated and tested to prove the concept of the design. A detailed description of the development with the results of the test measurements are presented. By using a new input structure and a new configuration of the ASIC, the dynamic range of the circuit is extended. A highly precise-time calibrating algorithm is also proposed, verified and optimized for the mass production. The test results suggest that the proposed electronics design fulfills the general specification of the future IACTs.

  8. How we read pediatric PET/CT: indications and strategies for image acquisition, interpretation and reporting.

    Science.gov (United States)

    Colleran, Gabrielle C; Kwatra, Neha; Oberg, Leah; Grant, Frederick D; Drubach, Laura; Callahan, Michael J; MacDougall, Robert D; Fahey, Frederic H; Voss, Stephan D

    2017-11-07

    PET/CT plays an important role in the diagnosis, staging and management of many pediatric malignancies. The techniques for performing PET/CT examinations in children have evolved, with increasing attention focused on reducing patient exposure to ionizing radiation dose whenever possible and minimizing scan duration and sedation times, with a goal toward optimizing the overall patient experience. This review outlines our approach to performing PET/CT, including a discussion of the indications for a PET/CT exam, approaches for optimizing the exam protocol, and a review of different approaches for acquiring the CT portion of the PET/CT exam. Strategies for PACS integration, image display, interpretation and reporting are also provided. Most practices will develop a strategy for performing PET/CT that best meets their respective needs. The purpose of this article is to provide a comprehensive overview for radiologists who are new to pediatric PET/CT, and also to provide experienced PET/CT practitioners with an update on state-of-the art CT techniques that we have incorporated into our protocols and that have enabled us to make considerable improvements to our PET/CT practice.

  9. Vibration Pattern Imager (VPI): A control and data acquisition system for scanning laser vibrometers

    Science.gov (United States)

    Rizzi, Stephen A.; Brown, Donald E.; Shaffer, Thomas A.

    1993-01-01

    The Vibration Pattern Imager (VPI) system was designed to control and acquire data from scanning laser vibrometer sensors. The PC computer based system uses a digital signal processing (DSP) board and an analog I/O board to control the sensor and to process the data. The VPI system was originally developed for use with the Ometron VPI Sensor, but can be readily adapted to any commercially available sensor which provides an analog output signal and requires analog inputs for control of mirror positioning. The sensor itself is not part of the VPI system. A graphical interface program, which runs on a PC under the MS-DOS operating system, functions in an interactive mode and communicates with the DSP and I/O boards in a user-friendly fashion through the aid of pop-up menus. Two types of data may be acquired with the VPI system: single point or 'full field.' In the single point mode, time series data is sampled by the A/D converter on the I/O board (at a user-defined sampling rate for a selectable number of samples) and is stored by the PC. The position of the measuring point (adjusted by mirrors in the sensor) is controlled via a mouse input. The mouse input is translated to output voltages by the D/A converter on the I/O board to control the mirror servos. In the 'full field' mode, the measurement point is moved over a user-selectable rectangular area. The time series data is sampled by the A/D converter on the I/O board (at a user-defined sampling rate for a selectable number of samples) and converted to a root-mean-square (rms) value by the DSP board. The rms 'full field' velocity distribution is then uploaded for display and storage on the PC.

  10. Rapid Assessment of Earthquakes with Radar and Optical Geodetic Imaging and Finite Fault Models (Invited)

    Science.gov (United States)

    Fielding, E. J.; Sladen, A.; Simons, M.; Rosen, P. A.; Yun, S.; Li, Z.; Avouac, J.; Leprince, S.

    2010-12-01

    Earthquake responders need to know where the earthquake has caused damage and what is the likely intensity of damage. The earliest information comes from global and regional seismic networks, which provide the magnitude and locations of the main earthquake hypocenter and moment tensor centroid and also the locations of aftershocks. Location accuracy depends on the availability of seismic data close to the earthquake source. Finite fault models of the earthquake slip can be derived from analysis of seismic waveforms alone, but the results can have large errors in the location of the fault ruptures and spatial distribution of slip, which are critical for estimating the distribution of shaking and damage. Geodetic measurements of ground displacements with GPS, LiDAR, or radar and optical imagery provide key spatial constraints on the location of the fault ruptures and distribution of slip. Here we describe the analysis of interferometric synthetic aperture radar (InSAR) and sub-pixel correlation (or pixel offset tracking) of radar and optical imagery to measure ground coseismic displacements for recent large earthquakes, and lessons learned for rapid assessment of future events. These geodetic imaging techniques have been applied to the 2010 Leogane, Haiti; 2010 Maule, Chile; 2010 Baja California, Mexico; 2008 Wenchuan, China; 2007 Tocopilla, Chile; 2007 Pisco, Peru; 2005 Kashmir; and 2003 Bam, Iran earthquakes, using data from ESA Envisat ASAR, JAXA ALOS PALSAR, NASA Terra ASTER and CNES SPOT5 satellite instruments and the NASA/JPL UAVSAR airborne system. For these events, the geodetic data provided unique information on the location of the fault or faults that ruptured and the distribution of slip that was not available from the seismic data and allowed the creation of accurate finite fault source models. In many of these cases, the fault ruptures were on previously unknown faults or faults not believed to be at high risk of earthquakes, so the area and degree of

  11. Using multimodal imaging techniques to monitor limb ischemia: a rapid noninvasive method for assessing extremity wounds

    Science.gov (United States)

    Luthra, Rajiv; Caruso, Joseph D.; Radowsky, Jason S.; Rodriguez, Maricela; Forsberg, Jonathan; Elster, Eric A.; Crane, Nicole J.

    2013-03-01

    Over 70% of military casualties resulting from the current conflicts sustain major extremity injuries. Of these the majority are caused by blasts from improvised explosive devices. The resulting injuries include traumatic amputations, open fractures, crush injuries, and acute vascular disruption. Critical tissue ischemia—the point at which ischemic tissues lose the capacity to recover—is therefore a major concern, as lack of blood flow to tissues rapidly leads to tissue deoxygenation and necrosis. If left undetected or unaddressed, a potentially salvageable limb may require more extensive debridement or, more commonly, amputation. Predicting wound outcome during the initial management of blast wounds remains a significant challenge, as wounds continue to "evolve" during the debridement process and our ability to assess wound viability remains subjectively based. Better means of identifying critical ischemia are needed. We developed a swine limb ischemia model in which two imaging modalities were combined to produce an objective and quantitative assessment of wound perfusion and tissue viability. By using 3 Charge-Coupled Device (3CCD) and Infrared (IR) cameras, both surface tissue oxygenation as well as overall limb perfusion could be depicted. We observed a change in mean 3CCD and IR values at peak ischemia and during reperfusion correlate well with clinically observed indicators for limb function and vitality. After correcting for baseline mean R-B values, the 3CCD values correlate with surface tissue oxygenation and the IR values with changes in perfusion. This study aims to not only increase fundamental understanding of the processes involved with limb ischemia and reperfusion, but also to develop tools to monitor overall limb perfusion and tissue oxygenation in a clinical setting. A rapid and objective diagnostic for extent of ischemic damage and overall limb viability could provide surgeons with a more accurate indication of tissue viability. This may

  12. Development of a hybrid MSGC detector for thermal neutron imaging with a MHz data acquisition and histogramming system

    CERN Document Server

    Gebauer, B; Richter, G; Levchanovsky, F V; Nikiforov, A

    2001-01-01

    For thermal neutron imaging at the next generation of high-flux pulsed neutron sources a large area and fourfold segmented, hybrid, low-pressure, two-dimensional position sensitive, microstrip gas chamber detector, fabricated in a multilayer technology on glass substrates, is presently being developed, which utilizes a thin composite sup 1 sup 5 sup 7 Gd/CsI neutron converter. The present article focusses on the readout scheme and the data acquisition (DAQ) system. For position encoding, interpolating and fast multihit delay line based electronics is applied with up to eightfold sub-segmentation per geometrical detector segment. All signals, i.e. position, time-of-flight and pulse-height signals, are fed into deadtime-less 8-channel multihit TDC chips with 120 ps LSB via constant fraction and time-over-threshold discriminators, respectively. The multihit capability is utilized to raise the count rate limit in combination with a sum check algorithm for disentangling pulses from different events. The first vers...

  13. Linear terrestrial laser scanning using array avalanche photodiodes as detectors for rapid three-dimensional imaging.

    Science.gov (United States)

    Cai, Yinqiao; Tong, Xiaohua; Tong, Peng; Bu, Hongyi; Shu, Rong

    2010-12-01

    As an active remote sensor technology, the terrestrial laser scanner is widely used for direct generation of a three-dimensional (3D) image of an object in the fields of geodesy, surveying, and photogrammetry. In this article, a new laser scanner using array avalanche photodiodes, as designed by the Shanghai Institute of Technical Physics of the Chinese Academy of Sciences, is introduced for rapid collection of 3D data. The system structure of the new laser scanner is first presented, and a mathematical model is further derived to transform the original data to the 3D coordinates of the object in a user-defined coordinate system. The performance of the new laser scanner is tested through a comprehensive experiment. The result shows that the new laser scanner can scan a scene with a field view of 30° × 30° in 0.2 s and that, with respect to the point clouds obtained on the wall and ground floor surfaces, the root mean square errors for fitting the two planes are 0.21 and 0.01 cm, respectively. The primary advantages of the developed laser scanner include: (i) with a line scanning mode, the new scanner achieves simultaneously the 3D coordinates of 24 points per single laser pulse, which enables it to scan faster than traditional scanners with a point scanning mode and (ii) the new scanner makes use of two galvanometric mirrors to deflect the laser beam in both the horizontal and the vertical directions. This capability makes the instrument smaller and lighter, which is more acceptable for users.

  14. Acquisition Research Program Homepage

    OpenAIRE

    2015-01-01

    Includes an image of the main page on this date and compressed file containing additional web pages. Established in 2003, Naval Postgraduate School’s (NPS) Acquisition Research Program provides leadership in innovation, creative problem solving and an ongoing dialogue, contributing to the evolution of Department of Defense acquisition strategies.

  15. An image-intensive ePR for image-guided minimally invasive spine surgery applications including real-time intra-operative image acquisition, archival, and display

    Science.gov (United States)

    Documet, Jorge R.; Le, Anh; Liu, Brent; Huang, H. K.; Chiu, John

    2009-02-01

    Recent developments in medical imaging informatics have improved clinical workflow in Radiology enterprise but gaps remain in the clinical workflow from diagnosis to surgical treatment through post-operative follow-up. One solution to bridge this gap is the development of an electronic patient record (ePR) that integrates key imaging and informatics data during the pre, intra, and post-operative phases of clinical workflow. We present an ePR system based on standards and tailored to the clinical application for image-guided minimally invasive spinal surgery (MISS). The ePR system has been implemented in a clinical environment for a half-year.

  16. Image quality of ultra-low-dose dual-source CT angiography using high-pitch spiral acquisition and iterative reconstruction in young children with congenital heart disease.

    Science.gov (United States)

    Zheng, Minwen; Zhao, Hongliang; Xu, Jian; Wu, Yongjie; Li, Jian

    2013-01-01

    Obtaining diagnostic CT image quality with ultra-low radiation dose in young children with congenital heart disease remains challenging. We evaluated the feasibility and image quality of prospectively electrocardiogram (ECG)-triggered high-pitch spiral acquisition with iterative reconstruction for pediatric cardiovascular CT angiography. Sixty-two consecutive pediatric patients younger than 2 years with congenital heart disease underwent prospectively ECG-triggered high-pitch spiral dual-source CT acquisition. Patients were randomly assigned into 2 groups: full tube current (40-70 mAs) scans with filtered back projection reconstruction (group A) and half tube current (20-35 mAs) scans with sinogram-affirmed iterative reconstruction (group B). Attenuation, noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and subjective image quality were compared between the 2 groups. Effective radiation dose was also estimated for both groups. No significant difference was found in the attenuation, image noise, SNR, and CNR between the 2 groups in the same evaluated anatomic regions, whereas the attenuation and image noise were slightly lower, and the SNR and CNR were slightly higher in group B. No significant difference was found in subjective image quality between the 2 groups (4.27 ± 0.73 vs. 4.34 ± 0.42; P = .813). Effective dose was 0.06 ± 0.03 mSv in group B and 0.13 ± 0.04 mSv in group A, reflecting dose savings of 53.8% by using iterative reconstruction. A combination of prospectively ECG-triggered high-pitch spiral acquisition, low tube current, and iterative reconstruction may offer diagnostic image quality in pediatric cardiovascular CT angiography with effective radiation dose < 0.1 mSv. Copyright © 2013 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

  17. Impact of PET acquisition durations on image quality and lesion detectability in whole-body (68)Ga-PSMA PET-MRI.

    Science.gov (United States)

    Noto, Benjamin; Büther, Florian; Auf der Springe, Katharina; Avramovic, Nemanja; Heindel, Walter; Schäfers, Michael; Allkemper, Thomas; Stegger, Lars

    2017-12-01

    While (68)Ga-PSMA PET-MRI might be superior to PET-CT with regard to soft tissue assessment in prostate cancer evaluation, it is also known to potentially introduce additional PET image artefacts. Therefore, the impact of PET acquisition duration and attenuation data on artefact occurrence, lesion detectability, and quantification was investigated. To this end, whole-body PET list mode data from 12 patients with prostate cancer were acquired 1 h after injection of 2 MBq/kg [(68)Ga]HBED-CC-PSMA on a hybrid PET-MRI system. List mode data were further transformed into data sets representing 300, 180, 90, and 30 s acquisition duration per bed position. Standard attenuation and scatter corrections were performed based on MRI-derived attenuation maps, complemented by emission-based attenuation data in areas not covered by MRI. A total of 288 image data sets were reconstructed with varying acquisition durations for emission and attenuation data with and without scatter and prompt gamma correction, and further analysed regarding image quality and diagnostic performance. Decreased PET acquisition durations resulted in a significantly increased incidence of halo artefacts around kidneys and bladder, decreased lesion detectability and lower SUV as well as markedly lower arm attenuation values: Halo artefacts were present in 5 out of 12 cases at 300-s duration, in 6 at 180 s, in 10 at 90 s, and in 11 cases at 30 s. Using attenuation data of the 300 s scans restored artefact occurrence to the original 300-s level. Prompt gamma correction only led to small improvements in terms of artefact occurrence and size. Of the 141 detected lesions in the 300-s images one lesion was not detected at 180 s, 28 at 90 s, and 64 at 30 s. Using the 300-s attenuation map decreased non-detectability of lesions to zero at 180 s, 9 at 90 s, and 52 at 30 s. Attenuation maps at 90 and 30 s demonstrated markedly lower mean arm attenuation values (0.002 cm(-1)) than those at 300 s (0

  18. Rapid detection of parasite in muscle fibers of fishes using a portable microscope imaging technique (Conference Presentation)

    Science.gov (United States)

    Lee, Jayoung; Lee, Hoonsoo; Kim, Moon S.; Cho, Byoungkwan

    2017-05-01

    Fishes are a widely used food material in the world. Recently about 4% of the fishes are infected with Kudoa thyrsites in Asian ocean. Kudoa thyrsites is a parasite that is found within the muscle fibers of fishes. The infected fishes can be a reason of food poisoning, which should be sorted out before distribution and consumption. Although Kudoa thyrsites is visible to the naked eye, it could be easily overlooked due to the micro-scale size and similar color with fish tissue. In addition, the visual inspection is labor intensive works resulting in loss of money and time. In this study, a portable microscopic camera was utilized to obtain images of raw fish slices. The optimized image processing techniques with polarized transmittance images provided reliable performance. The result shows that the portable microscopic imaging method can be used to detect parasites rapidly and non-destructively, which could be an alternative to manual inspections.

  19. Spectral phasor analysis allows rapid and reliable unmixing of fluorescence microscopy spectral images

    NARCIS (Netherlands)

    Fereidouni, F.|info:eu-repo/dai/nl/372641431; Bader, A.N.|info:eu-repo/dai/nl/291137334; Gerritsen, H.C.|info:eu-repo/dai/nl/071548777

    2012-01-01

    A new global analysis algorithm to analyse (hyper-) spectral images is presented. It is based on the phasor representation that has been demonstrated to be very powerful for the analysis of lifetime imaging data. In spectral phasor analysis the fluorescence spectrum of each pixel in the image is

  20. Multiplexed Eighty Channel PMT List-Mode Data Acquisition System for 27-511 keV Gamma Ray Imaging

    Science.gov (United States)

    Tapias, G.; Villena, J. L.; Kreuger, R.; Lage, E.; Beekman, F. J.

    2012-06-01

    We have developed an 80-channel readout system for gamma cameras which acquires PMT signals and stores them in list-mode format on a computer. The system combines low noise and a large signal range to handle PMT signals from a wide range of SPECT and PET tracers simultaneously (27 to 511 keV). All channels of the read-out system have a gated integrator to determine the charge per event. Each 16 channels are multiplexed to a 12-bit 40 MS/s pipelined ADCs. Using multiplexing only 5 ADCs are needed which share a commercial USB 2.0 interface board to send the event data to the computer. The signal input range is up to 120 pC with a noise level of 57 fC. The integral non-linearity is better than 1% for all channels, while the channel response has a gain non-uniformity less than 2.4% for the different channels. The crosstalk between channels is better than 64 dB. The dead time is 2.5 μs, including a 760 ns integration period. The system can handle a sustained event rate of 155 kcps on the USB 2.0 bus. Connected to a clinical gamma camera we show that the isotopes 125I (27-35 keV), 99mTc (140.5 keV) and 22Na (511 keV) can all be imaged without electronic adjustments thus enabling, for instance, simultaneous pinhole PET/SPECT. With this PMT list-mode acquisition system, advanced offline event positioning and energy estimation with e.g. maximum likelihood methods are enabled.

  1. Towards the low-dose characterization of beam sensitive nanostructures via implementation of sparse image acquisition in scanning transmission electron microscopy

    Science.gov (United States)

    Hwang, Sunghwan; Han, Chang Wan; Venkatakrishnan, Singanallur V.; Bouman, Charles A.; Ortalan, Volkan

    2017-04-01

    Scanning transmission electron microscopy (STEM) has been successfully utilized to investigate atomic structure and chemistry of materials with atomic resolution. However, STEM’s focused electron probe with a high current density causes the electron beam damages including radiolysis and knock-on damage when the focused probe is exposed onto the electron-beam sensitive materials. Therefore, it is highly desirable to decrease the electron dose used in STEM for the investigation of biological/organic molecules, soft materials and nanomaterials in general. With the recent emergence of novel sparse signal processing theories, such as compressive sensing and model-based iterative reconstruction, possibilities of operating STEM under a sparse acquisition scheme to reduce the electron dose have been opened up. In this paper, we report our recent approach to implement a sparse acquisition in STEM mode executed by a random sparse-scan and a signal processing algorithm called model-based iterative reconstruction (MBIR). In this method, a small portion, such as 5% of randomly chosen unit sampling areas (i.e. electron probe positions), which corresponds to pixels of a STEM image, within the region of interest (ROI) of the specimen are scanned with an electron probe to obtain a sparse image. Sparse images are then reconstructed using the MBIR inpainting algorithm to produce an image of the specimen at the original resolution that is consistent with an image obtained using conventional scanning methods. Experimental results for down to 5% sampling show consistency with the full STEM image acquired by the conventional scanning method. Although, practical limitations of the conventional STEM instruments, such as internal delays of the STEM control electronics and the continuous electron gun emission, currently hinder to achieve the full potential of the sparse acquisition STEM in realizing the low dose imaging condition required for the investigation of beam-sensitive materials

  2. NDER: A novel web application using annotated whole slide images for rapid improvements in human pattern recognition

    Directory of Open Access Journals (Sweden)

    Nicholas P Reder

    2016-01-01

    Full Text Available Context: Whole-slide images (WSIs present a rich source of information for education, training, and quality assurance. However, they are often used in a fashion similar to glass slides rather than in novel ways that leverage the advantages of WSI. We have created a pipeline to transform annotated WSI into pattern recognition training, and quality assurance web application called novel diagnostic electronic resource (NDER. Aims: Create an efficient workflow for extracting annotated WSI for use by NDER, an attractive web application that provides high-throughput training. Materials and Methods: WSI were annotated by a resident and classified into five categories. Two methods of extracting images and creating image databases were compared. Extraction Method 1: Manual extraction of still images and validation of each image by four breast pathologists. Extraction Method 2: Validation of annotated regions on the WSI by a single experienced breast pathologist and automated extraction of still images tagged by diagnosis. The extracted still images were used by NDER. NDER briefly displays an image, requires users to classify the image after time has expired, then gives users immediate feedback. Results: The NDER workflow is efficient: annotation of a WSI requires 5 min and validation by an expert pathologist requires An additional one to 2 min. The pipeline is highly automated, with only annotation and validation requiring human input. NDER effectively displays hundreds of high-quality, high-resolution images and provides immediate feedback to users during a 30 min session. Conclusions: NDER efficiently uses annotated WSI to rapidly increase pattern recognition and evaluate for diagnostic proficiency.

  3. Direct, rapid antimicrobial susceptibility test from positive blood cultures based on microscopic imaging analysis

    OpenAIRE

    Choi, Jungil; Jeong, Hyun Yong; Lee, Gi Yoon; Han, Sangkwon; Han, Shinhun; Jin, Bonghwan; Lim, Taegeun; Kim, Shin; Kim, Dong Young; Kim, Hee Chan; Kim, Eui-Chong; Song, Sang Hoon; Kim, Taek Soo; Kwon, Sunghoon

    2017-01-01

    For the timely treatment of patients with infections in bloodstream and cerebrospinal fluid, a rapid antimicrobial susceptibility test (AST) is urgently needed. Here, we describe a direct and rapid antimicrobial susceptibility testing (dRAST) system, which can determine the antimicrobial susceptibility of bacteria from a positive blood culture bottle (PBCB) in six hours. The positive blood culture sample is directly mixed with agarose and inoculated into a micropatterned plastic microchip wit...

  4. Shadow and feature recognition aids for rapid image geo-registration in UAV vision system architectures

    Science.gov (United States)

    Baer, Wolfgang; Kölsch, Mathias

    2009-05-01

    The problem of real-time image geo-referencing is encountered in all vision based cognitive systems. In this paper we present a model-image feedback approach to this problem and show how it can be applied to image exploitation from Unmanned Arial Vehicle (UAV) vision systems. By calculating reference images from a known terrain database, using a novel ray trace algorithm, we are able to eliminate foreshortening, elevation, and lighting distortions, introduce registration aids and reduce the geo-referencing problem to a linear transformation search over the two dimensional image space. A method for shadow calculation that maintains real-time performance is also presented. The paper then discusses the implementation of our model-image feedback approach in the Perspective View Nascent Technology (PVNT) software package and provides sample results from UAV mission control and target mensuration experiments conducted at China Lake and Camp Roberts, California.

  5. Rapid Measurements of Intensities for Safety Assessment of Advanced Imaging Sequences

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Rasmussen, Morten Fischer; Stuart, Matthias Bo

    2014-01-01

    FDA requires that intensity and safety parameters are measured for all imaging schemes for clinical imaging. This is often cumbersome, since the scan sequence has to broken apart, measurements conducted for the individually emitted beams, and the nal intensity levels calculated by combining the i...

  6. Rapid Retrieval of Lung Nodule CT Images Based on Hashing and Pruning Methods

    Directory of Open Access Journals (Sweden)

    Ling Pan

    2016-01-01

    Full Text Available The similarity-based retrieval of lung nodule computed tomography (CT images is an important task in the computer-aided diagnosis of lung lesions. It can provide similar clinical cases for physicians and help them make reliable clinical diagnostic decisions. However, when handling large-scale lung images with a general-purpose computer, traditional image retrieval methods may not be efficient. In this paper, a new retrieval framework based on a hashing method for lung nodule CT images is proposed. This method can translate high-dimensional image features into a compact hash code, so the retrieval time and required memory space can be reduced greatly. Moreover, a pruning algorithm is presented to further improve the retrieval speed, and a pruning-based decision rule is presented to improve the retrieval precision. Finally, the proposed retrieval method is validated on 2,450 lung nodule CT images selected from the public Lung Image Database Consortium (LIDC database. The experimental results show that the proposed pruning algorithm effectively reduces the retrieval time of lung nodule CT images and improves the retrieval precision. In addition, the retrieval framework is evaluated by differentiating benign and malignant nodules, and the classification accuracy can reach 86.62%, outperforming other commonly used classification methods.

  7. Rapid Retrieval of Lung Nodule CT Images Based on Hashing and Pruning Methods.

    Science.gov (United States)

    Pan, Ling; Qiang, Yan; Yuan, Jie; Wu, Lidong

    2016-01-01

    The similarity-based retrieval of lung nodule computed tomography (CT) images is an important task in the computer-aided diagnosis of lung lesions. It can provide similar clinical cases for physicians and help them make reliable clinical diagnostic decisions. However, when handling large-scale lung images with a general-purpose computer, traditional image retrieval methods may not be efficient. In this paper, a new retrieval framework based on a hashing method for lung nodule CT images is proposed. This method can translate high-dimensional image features into a compact hash code, so the retrieval time and required memory space can be reduced greatly. Moreover, a pruning algorithm is presented to further improve the retrieval speed, and a pruning-based decision rule is presented to improve the retrieval precision. Finally, the proposed retrieval method is validated on 2,450 lung nodule CT images selected from the public Lung Image Database Consortium (LIDC) database. The experimental results show that the proposed pruning algorithm effectively reduces the retrieval time of lung nodule CT images and improves the retrieval precision. In addition, the retrieval framework is evaluated by differentiating benign and malignant nodules, and the classification accuracy can reach 86.62%, outperforming other commonly used classification methods.

  8. Rapid Assessment of Tablet Film Coating Quality by Multispectral UV Imaging

    DEFF Research Database (Denmark)

    Klukkert, Marten; Wu, Jian X.; Rantanen, Jukka

    2016-01-01

    and coated with a polyvinyl alcohol-polyethylene glycol graft copolymer using a pan coater. It was demonstrated that the coating intactness can be assessed accurately and fast by UV imaging. The different types of coating defects could be differentiated and localized based on multivariate image analysis...

  9. Dark blood versus bright blood T2* acquisition in cardiovascular magnetic resonance (CMR) for thalassaemia major (TM) patients: Evaluation of feasibility, reproducibility and image quality

    Energy Technology Data Exchange (ETDEWEB)

    Liguori, Carlo, E-mail: c.liguori@unicampus.it [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Di Giampietro, Ilenia; Pitocco, Francesca; De Vivo, Aldo Eros [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Schena, Emiliano [Unit of Measurements and Biomedical Instrumentation, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Mortato, Luca [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Pirro, Federica [Department of Biomaging and Radiological Sciences, Catholic University of Sacred Herart, Largo A. Gemelli 1, 00135 Rome (Italy); Cianciulli, Paolo [Thalassemia Unit, Ospedale Sant Eugenio, Piazzale dell’Umanesimo 10, 00143 Rome (Italy); Zobel, Bruno Beomonte [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy)

    2014-01-15

    Objectives: To compare the effectiveness of dark blood (DB) versus bright blood (BB) sequences. To assess the intra and inter-observer variability and inter-study reproducibility between BB versus DB. To evaluate image quality level in the two sequences. Methods: In a setting of 138 patients we performed CMR using cardiac gated Gradient-multiecho single breath-hold BB and DB sequences in the middle ventricular septum. Each acquisition was repeated during the same exam. Truncation method was used to account for background noise. Image quality (IQ) was assessed using a 5 point grading scale and image analysis was conducted by 2 experienced observers. Results: Compared with the conventional BB acquisition, the coefficient of correlation and significance of the DB technique was superior for intra-observer reproducibility (p < 0.001), inter-observer reproducibility (p < 0.001) and inter-study reproducibility (p < 0.001). The variability is also lower for DB sequences for T2* values <14 ms. Assessment of artifacts showed a superior score for DB versus BB scans (4 versus 3, p < 0.001). Conclusions: Improvement in terms of inter observer and inter study variability using DB sequences was obtained. The greatest disparity between them was seen in inter-study reproducibility and higher IQ in DB was seen. Study demonstrates better performance of DB imaging compared to BB in presence of comparable effectiveness.

  10. Evaluation of image quality for different kV cone-beam CT acquisition and reconstruction methods in the head and neck region

    Energy Technology Data Exchange (ETDEWEB)

    Elstroem, Ulrik V.; Muren, Ludvig P. (Dept. of Oncology, Aarhus Univ. Hospital, Aarhus (Denmark); Dept. of Medical Physics, Aarhus Univ. Hospital, Aarhus (Denmark)), e-mail: ulrielst@rm.dk; Petersen, Joergen B. B. (Dept. of Medical Physics, Aarhus Univ. Hospital, Aarhus (Denmark)); Grau, Cai (Dept. of Oncology, Aarhus Univ. Hospital, Aarhus (Denmark))

    2011-08-15

    Purpose. To evaluate the image quality obtained in a standard QA phantom with both clinical and non-clinical cone-beam computed tomography (CBCT) acquisition modes for the head and neck (HN) region as a step towards CBCT-based treatment planning. The impact of deteriorated Hounsfield unit (HU) accuracy was investigated by comparing results from clinical CBCT image reconstructions to those obtained from a pre-clinical scatter correction algorithm. Methods. Five different CBCT acquisition modes on a clinical system for kV CBCT-guided radiotherapy were investigated. Image reconstruction was performed in both standard clinical software and with an experimental reconstruction algorithm with improved beam hardening and scatter correction. Using the Catphan 504 phantom, quantitative measures of HU uniformity, HU verification and linearity, contrast-to-noise ratio (CNR), and spatial resolution using modulation transfer function (MTF) estimation were assessed. To benchmark the CBCT image properties, comparison to standard HN protocols on conventional CT scanners was performed by similar measures. Results. The HU uniformity within a water-equivalent homogeneous region was considerably improved using experimental vs. standard reconstruction, by factors of two for partial scans and four for full scans. Similarly, the amount of capping/cupping artifact was reduced by more than 1.5%. With mode and reconstruction specific HU calibration using seven inhomogeneity inserts comparable HU linearity was observed. CNR was on average 5% higher for experimental reconstruction (scaled with the square-root of dose between modes for both reconstruction methods). Conclusions. Judged on parameters affecting the common diagnostic image properties, improved beam hardening and scatter correction diminishes the difference between CBCT and CT image quality considerably. In the pursuit of CBCT-based treatment adaptation, dedicated imaging protocols may be required

  11. Television, disordered eating, and young women in Fiji: negotiating body image and identity during rapid social change.

    Science.gov (United States)

    Becker, Anne E

    2004-12-01

    Although the relationship between media exposure and risk behavior among youth is established at a population level, the specific psychological and social mechanisms mediating the adverse effects of media on youth remain poorly understood. This study reports on an investigation of the impact of the introduction of television to a rural community in Western Fiji on adolescent ethnic Fijian girls in a setting of rapid social and economic change. Narrative data were collected from 30 purposively selected ethnic Fijian secondary school girls via semi-structured, open-ended interviews. Interviews were conducted in 1998, 3 years after television was first broadcast to this region of Fiji. Narrative data were analyzed for content relating to response to television and mechanisms that mediate self and body image in Fijian adolescents. Data in this sample suggest that media imagery is used in both creative and destructive ways by adolescent Fijian girls to navigate opportunities and conflicts posed by the rapidly changing social environment. Study respondents indicated their explicit modeling of the perceived positive attributes of characters presented in television dramas, but also the beginnings of weight and body shape preoccupation, purging behavior to control weight, and body disparagement. Response to television appeared to be shaped by a desire for competitive social positioning during a period of rapid social transition. Understanding vulnerability to images and values imported with media will be critical to preventing disordered eating and, potentially, other youth risk behaviors in this population, as well as other populations at risk.

  12. Development of a symmetric echo planar imaging framework for clinical translation of rapid dynamic hyperpolarized 13 C imaging.

    Science.gov (United States)

    Gordon, Jeremy W; Vigneron, Daniel B; Larson, Peder E Z

    2017-02-01

    To develop symmetric echo planar imaging (EPI) and a reference scan framework for hyperpolarized 13 C metabolic imaging. Symmetric, ramp-sampled EPI with partial Fourier reconstruction was implemented on a 3T scanner. The framework for acquiring a reference scan on the 1 H channel and applied to 13 C data was described and validated in both phantoms and in vivo metabolism of [1-13 C]pyruvate. Ramp-sampled, symmetric EPI provided a substantial increase in the signal-to-noise ratio of the phantom experiments. The reference scan acquired on the 1 H channel yielded 13 C phantom images that varied in mean signal intensity Ramp-sampled, symmetric EPI with spectral-spatial excitation of a single metabolite provides a fast, robust, and clinically efficacious approach to acquire hyperpolarized 13 C dynamic molecular imaging data. The gains of this efficient sampling, combined with partial Fourier methods, enables large matrix sizes required for human studies. Magn Reson Med 77:826-832, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  13. Hepatic adenomatosis: rapid sequence MR imaging following gadolinium enhancement: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Brummett, D. [Dept. of Radiology, Medical College of Georgia, Augusta (United States); Burton, E.M. [Dept. of Radiology, Medical College of Georgia, Augusta (United States)]|[Dept. of Pediatrics, Medical College of Georgia, Augusta (United States); Sabio, H. [Dept. of Pediatrics, Medical College of Georgia, Augusta (United States)

    1999-04-01

    Hepatic adenomas are primary liver tumors usually associated with underlying metabolic disease or with anabolic steroid or oral contraceptive use. Hepatic adenomatosis (HA) is defined as the presence of more than four adenomas. Only 13 cases of HA have been reported in patients without glycogen storage disease or steroid use. We report a case of HA imaged by postcontrast T1-weighted images obtained during a breath-holding series. The lesions were most conspicuous 3-4 min after contrast administration; 4 of the 5 tumors were not identified on T2-weighted images. Unlike previous reports of HA in which the lesions remained hyperintense during sequential postcontrast imaging, the smaller lesions in this case demonstrated contrast washout, thereby distinguishing them from hemangiomata. (orig.) With 3 figs., 10 refs.

  14. Process for rapid detection of fratricidal defects on optics using Linescan Phase Differential Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ravizza, F L; Nostrand, M C; Kegelmeyer, L M; Hawley, R A; Johnson, M A

    2009-11-05

    Phase-defects on optics used in high-power lasers can cause light intensification leading to laser-induced damage of downstream optics. We introduce Linescan Phase Differential Imaging (LPDI), a large-area dark-field imaging technique able to identify phase-defects in the bulk or surface of large-aperture optics with a 67 second scan-time. Potential phase-defects in the LPDI images are indentified by an image analysis code and measured with a Phase Shifting Diffraction Interferometer (PSDI). The PSDI data is used to calculate the defects potential for downstream damage using an empirical laser-damage model that incorporates a laser propagation code. A ray tracing model of LPDI was developed to enhance our understanding of its phase-defect detection mechanism and reveal limitations.

  15. Lobster-eye x-ray optics: a rapid evaluation of the image distribution.

    Science.gov (United States)

    Peele, A G; Nugent, K A

    1998-02-01

    A method for calculating the image distribution for one-dimensional lobster-eye optics is presented. This method gives the image distribution exactly for certain cases and offers improved speed over the method of ray tracing. Examples of the use of the algorithm are given. We show that the algorithm gives the same results as detailed ray-tracing codes. Extension of the method to the two-dimensional case is discussed.

  16. [Rapid 2D-3D medical image registration based on CUDA].

    Science.gov (United States)

    Li, Lingzhi; Zou, Beiji

    2014-08-01

    The medical image registration between preoperative three-dimensional (3D) scan data and intraoperative two-dimensional (2D) image is a key technology in the surgical navigation. Most previous methods need to generate 2D digitally reconstructed radiographs (DRR) images from the 3D scan volume data, then use conventional image similarity function for comparison. This procedure includes a large amount of calculation and is difficult to archive real-time processing. In this paper, with using geometric feature and image density mixed characteristics, we proposed a new similarity measure function for fast 2D-3D registration of preoperative CT and intraoperative X-ray images. This algorithm is easy to implement, and the calculation process is very short, while the resulting registration accuracy can meet the clinical use. In addition, the entire calculation process is very suitable for highly parallel numerical calculation by using the algorithm based on CUDA hardware acceleration to satisfy the requirement of real-time application in surgery.

  17. 3D noninvasive, high-resolution imaging using a photoacoustic tomography (PAT) system and rapid wavelength-cycling lasers

    Science.gov (United States)

    Sampathkumar, Ashwin; Gross, Daniel; Klosner, Marc; Chan, Gary; Wu, Chunbai; Heller, Donald F.

    2015-05-01

    Globally, cancer is a major health issue as advances in modern medicine continue to extend the human life span. Breast cancer ranks second as a cause of cancer death in women in the United States. Photoacoustic (PA) imaging (PAI) provides high molecular contrast at greater depths in tissue without the use of ionizing radiation. In this work, we describe the development of a PA tomography (PAT) system and a rapid wavelength-cycling Alexandrite laser designed for clinical PAI applications. The laser produces 450 mJ/pulse at 25 Hz to illuminate the entire breast, which eliminates the need to scan the laser source. Wavelength cycling provides a pulse sequence in which the output wavelength repeatedly alternates between 755 nm and 797 nm rapidly within milliseconds. We present imaging results of breast phantoms with inclusions of different sizes at varying depths, obtained with this laser source, a 5-MHz 128-element transducer and a 128-channel Verasonics system. Results include PA images and 3D reconstruction of the breast phantom at 755 and 797 nm, delineating the inclusions that mimic tumors in the breast.

  18. Rapid 3D imaging of the lower airway by MRI in patients with congenital heart disease: A retrospective comparison of delayed volume interpolated breath-hold examination (VIBE) to turbo spin echo (TSE).

    Science.gov (United States)

    Goot, Benjamin H; Patel, Sonali; Fonseca, Brian

    2017-01-01

    When imaging the lower airway by MRI, the traditional technique turbo spin echo (TSE) results in high quality 2D images, however planning and acquisition times are lengthy. An alternative, delayed volume interpolated breath-holds examination (VIBE), is a 3D gradient echo technique that produces high spatial resolution imaging of the airway in one breath-hold. The objective of this study is to retrospectively evaluate the accuracy of lower airway measurements obtained by delayed VIBE when compared to TSE. Patients with congenital heart disease who underwent a cardiac MRI (CMR) that included a delayed VIBE sequence from 5/2008 to 9/2013 were included. Standard TSE imaging was performed and delayed VIBE was acquired 5 min after gadolinium contrast administration. Airway measurements were made on both sequences by two observers in a blinded fashion to the other observer and other technique. Intraclass correlations (ICC) were calculated to assess for agreement between both techniques and the observers. 29 studies met inclusion criteria with a mean patient age of 8.8 years (2 months to 63 years) and mean patient weight of 30.2 kg (3.5-110). All delayed VIBE and TSE sequences were found to be of diagnostic quality. Mean acquisition time was shorter for the delayed VIBE (13.1 seconds) than TSE (949.9 seconds). Overall there was very good agreement between the delayed VIBE and TSE measurements for both observers (ICC 0.78-0.94) with the exception of the distal right bronchus (ICC 0.67) The interobserver agreement was also excellent for both TSE (ICC 0.78-0.96) and VIBE (ICC 0.85-0.96). Delayed VIBE is rapid and at least as accurate as the alternative TSE imaging for assessment of the lower airway by MRI across a wide spectrum of patients. © 2016 Wiley Periodicals, Inc.

  19. Test bed for real-time image acquisition and processing systems based on FlexRIO, CameraLink, and EPICS

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, E., E-mail: eduardo.barrera@upm.es [Grupo de Investigación en Instrumentación y Acústica Aplicada, Universidad Politécnica de Madrid (UPM) (Spain); Ruiz, M.; Sanz, D. [Grupo de Investigación en Instrumentación y Acústica Aplicada, Universidad Politécnica de Madrid (UPM) (Spain); Vega, J.; Castro, R. [Asociación EURATOM/CIEMAT para Fusión, Madrid (Spain); Juárez, E.; Salvador, R. [Centro de Investigación en Tecnologías Software y Sistemas Multimedia para la Sostenibilidad, Universidad Politécnica de Madrid (UPM) (Spain)

    2014-05-15

    Highlights: • The test bed allows for the validation of real-time image processing techniques. • Offers FPGA (FlexRIO) image processing that does not require CPU intervention. • Is fully compatible with the architecture of the ITER Fast Controllers. • Provides flexibility and easy integration in distributed experiments based on EPICS. - Abstract: Image diagnostics are becoming standard ones in nuclear fusion. At present, images are typically analyzed off-line. However, real-time processing is occasionally required (for instance, hot-spot detection or pattern recognition tasks), which will be the objective for the next generation of fusion devices. In this paper, a test bed for image generation, acquisition, and real-time processing is presented. The proposed solution is built using a Camera Link simulator, a Camera Link frame-grabber, a PXIe chassis, and offers software interface with EPICS. The Camera Link simulator (PCIe card PCIe8 DVa C-Link from Engineering Design Team) generates simulated image data (for example, from video-movies stored in fusion databases) using a Camera Link interface to mimic the frame sequences produced with diagnostic cameras. The Camera Link frame-grabber (FlexRIO Solution from National Instruments) includes a field programmable gate array (FPGA) for image acquisition using a Camera Link interface; the FPGA allows for the codification of ad-hoc image processing algorithms using LabVIEW/FPGA software. The frame grabber is integrated in a PXIe chassis with system architecture similar to that of the ITER Fast Controllers, and the frame grabber provides a software interface with EPICS to program all of its functionalities, capture the images, and perform the required image processing. The use of these four elements allows for the implementation of a test bed system that permits the development and validation of real-time image processing techniques in an architecture that is fully compatible with that of the ITER Fast Controllers

  20. Fast acceleration of ASL-based time-resolved magnetic resonance angiography by acquisition of control and labeled images in the same shot (fast ACTRESS): An optimization study.

    Science.gov (United States)

    Sugimori, Hiroyuki; Fujima, Noriyuki; Suzuki, Yuriko; Hamaguchi, Hiroyuki; Ishizaka, Kinya; Kudo, Kohsuke

    2017-11-01

    To establish an optimized sequence design for fast acceleration of arterial spin labeling (ASL)-based time-resolved magnetic resonance angiography (MRA) by acquisition of control and labeled images in the same shot (fast ACTRESS) and a scan time of <1min, for the evaluation of intracranial vessels. Ten healthy volunteers with no unilateral symptomatic arterial stenosis, who underwent 3-tesla MRI, were investigated. Imaging parameters for the fast ACTRESS sequence were set with an acquisition time of 45s. During post-processing, the first phase in the multi-phase readout, which was defined as the control image, was subtracted from each of the other phases. Thus, four-dimensional (4D)-MRA images of each phase were obtained. The maximum intensity projection was used for the reconstruction of 4D-MRA images and time-to-signal intensity curves (TIC) obtained for each vessel. The area under the curve (AUC), peak time, and maximum signal intensity were obtained from TIC. The different labeling types were broadly divided into six groups: L1, L2, L3, L4, L5, and L6 according to the actual number of labeling pulse. A total of 5040 regions of interest were evaluated. The peak SI of L3, except for those in the A2 segment of the anterior cerebral artery, was significantly higher than that of L5. However, there were no significant differences between L4 and L5. Although the AUCs of L3 and L4 for anterior circulation were relatively higher than that of the other subgroups, the AUC of L3 was significantly higher than that of L4. The fast ACTRESS was optimized and indicated that the labeling type of L3 was the most appropriate for the well visualization of intracranial arteries. The fast ACTRESS sequence was useful to acquire well-delineated images of intracranial vessels in ˂1min. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Tissue viability (TiVi) imaging: utility in assessment of rapid changes in the cutaneous microvasculature

    Science.gov (United States)

    McNamara, Paul M.; O'Doherty, Jim; O'Connell, Marie-Louise; Fitzgerald, Barry W.; Anderson, Chris D.; Nilsson, Gert E.; Leahy, Martin J.

    2010-02-01

    This report outlines results from an independent study assessing the clinical potential of an emerging, contemporary imaging technology. Tissue Viability (TiVi) imaging is an easily implemented, non-invasive, and portable technique which maps the blood circulation in the surface dermal layer. However, its routine clinical implementation awaits the development of the necessary standardised protocols. Thus the pilot study examines the efficacy of a novel TiVi imaging device within a localised skin blood flow occlusion protocol. The test was administered to the upper volar forearm of 19 healthy subjects (10:9 Female:Male) for 5 different time periods ranging from 5 to 25 seconds. Dermal areas corresponding to 100 × 100 pixels (2.89 cm2) were monitored for 60 seconds prior to, during and after each occlusal test. Our results support the relevance of a TiVi occlusion protocol for physiological assessment of the skin microcirculation.

  2. Rapid Cancer Fluorescence Imaging Using A γ-Glutamyltranspeptidase-Specific Probe For Primary Lung Cancer

    Directory of Open Access Journals (Sweden)

    Haruaki Hino

    2016-06-01

    Full Text Available BACKGROUND: We set out to examine the activity of γ-glutamyltranspeptidase (GGT in lung cancer and the validity of γ-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG for intraoperative imaging of primary lung cancer. METHODS: GGT activities and mRNA expression levels of GGT1 (one of the GGT subtypes in five human lung cancer cell lines were examined by fluorescence imaging and quantitative reverse transcription polymerase chain reaction. In vivo imaging of an orthotopic A549 xenograft model in nude mice was performed to confirm its applicability to intraoperative imaging. Furthermore, ex vivo imaging of 73 specimens from lung cancer patients were performed and analyzed to calculate the sensitivity/specificity of gGlu-HMRG for lung cancer diagnosis. RESULTS: GGT activities and mRNA expression levels of GGT1 are diverse depending on cell type; A549, H441, and H460 showed relatively high GGT activities and expression levels, whereas H82 and H226 showed lower values. In the in vivo mouse model study, tiny pleural dissemination and hilar/mediastinal lymph node metastasis (less than 1 mm in diameter were clearly detected 15 minutes after topical application of gGlu-HMRG. In the ex vivo study of specimens from patients, the sensitivity and specificity of gGlu-HMRG were calculated to be 43.8% (32/73 and 84.9% (62/73, respectively. When limited to female patients, never smokers, and adenocarcinomas, these values were 78.9% (15/19 and 73.7% (14/19, respectively. CONCLUSIONS: Although GGT activity of lung cancer cells vary, gGlu-HMRG can serve as an intraoperative imaging tool to detect small foci of lung cancer when such cells have sufficient GGT activity.

  3. Acquisition of the Gatan Image Filter System and an Environmental Cell for an Existing Phillips CM-200 FEG-TEM

    National Research Council Canada - National Science Library

    Aksay, Ilhan

    2001-01-01

    ...) with short acquisition times (seconds). In the past 5 years, we have made exciting progress in both research and education at Princeton and have made an impact in the materials science community by utilizing this state-of-the-art electron...

  4. Rest myocardial perfusion/metabolism imaging using simultaneous dual-isotope acquisition SPECT with technetium-99m-MIBI/fluorine-18-FDG.

    Science.gov (United States)

    Delbeke, D; Videlefsky, S; Patton, J A; Campbell, M G; Martin, W H; Ohana, I; Sandler, M P

    1995-11-01

    The purpose of this study was to develop a dual-isotope simultaneous acquisition (DISA) protocol using a multihead SPECT camera equipped with an ultrahigh-energy (UHE) collimator to evaluate simultaneously rest cardiac perfusion and metabolism with 99mTc-MIBI/18FDG. Physical measurements were first performed with phantoms to develop the acquisition protocol. Fifteen patients underwent DISA-SPECT with 99mTc-MIBI/18FDG to validate the protocol. To evaluate the quality of the 99mTc-MIBI images acquired with the UHE collimator, four patients underwent a resting 99mTc-MIBI scan acquired with a high-resolution, low-energy collimator prior to DISA-SPECT. With a window of 20% for both photopeaks and a 99mTc/18F concentration ratio of 3.2:1, the spillover from 18F into the 99mTc window is 6% of the counts in the window for normal subjects. Phantom images clearly demonstrated defects measuring 2 x 1 and 2 x 0.5 cm. Technetium-99m-MIBI images obtained with the UHE and high-resolution collimators provided similar diagnostic information. Using a stenosis of > 70% as criteria to diagnose coronary artery disease, DISA-SPECT had a sensitivity of 100% and a positive predictive value of 93%. Simultaneous evaluation of rest myocardial perfusion/metabolism with a multihead SPECT camera equipped with an UHE collimator is possible using 99mTc-MIBI/18FDG with a dual-isotope simultaneous acquisition protocol.

  5. Study on clear stereo image pair acquisition method for small objects with big vertical size in SLM vision system.

    Science.gov (United States)

    Wang, Yuezong; Jin, Yan; Wang, Lika; Geng, Benliang

    2016-05-01

    Microscopic vision system with stereo light microscope (SLM) has been applied to surface profile measurement. If the vertical size of a small object exceeds the range of depth, its images will contain clear and fuzzy image regions. Hence, in order to obtain clear stereo images, we propose a microscopic sequence image fusion method which is suitable for SLM vision system. First, a solution to capture and align image sequence is designed, which outputs an aligning stereo images. Second, we decompose stereo image sequence by wavelet analysis theory, and obtain a series of high and low frequency coefficients with different resolutions. Then fused stereo images are output based on the high and low frequency coefficient fusion rules proposed in this article. The results show that Δw1 (Δw2 ) and ΔZ of stereo images in a sequence have linear relationship. Hence, a procedure for image alignment is necessary before image fusion. In contrast with other image fusion methods, our method can output clear fused stereo images with better performance, which is suitable for SLM vision system, and very helpful for avoiding image fuzzy caused by big vertical size of small objects. © 2016 Wiley Periodicals, Inc.

  6. Diagnosing lung nodules on oncologic MR/PET imaging: Comparison of fast T1-weighted sequences and influence of image acquisition in inspiration and expiration breath-hold

    Energy Technology Data Exchange (ETDEWEB)

    Schwenzer, Nina F.; Seith, Ferdinand; Gatidis, Sergios; Brendle, Cornelia; Schmidt, Holger; Pfannenberg, Christina A; LaFougère, Christian; Nikolaou, Konstantin; Schraml, Christina [University Hospital of Tuebingen, Tuebingen (Germany)

    2016-09-15

    First, to investigate the diagnostic performance of fast T1-weighted sequences for lung nodule evaluation in oncologic magnetic resonance (MR)/positron emission tomography (PET). Second, to evaluate the influence of image acquisition in inspiration and expiration breath-hold on diagnostic performance. The study was approved by the local Institutional Review Board. PET/CT and MR/PET of 44 cancer patients were evaluated by 2 readers. PET/CT included lung computed tomography (CT) scans in inspiration and expiration (CTin, CTex). MR/PET included Dixon sequence for attenuation correction and fast T1-weighted volumetric interpolated breath-hold examination (VIBE) sequences (volume interpolated breath-hold examination acquired in inspiration [VIBEin], volume interpolated breath-hold examination acquired in expiration [VIBEex]). Diagnostic performance was analyzed for lesion-, lobe-, and size-dependence. Diagnostic confidence was evaluated (4-point Likert-scale; 1 = high). Jackknife alternative free-response receiver-operating characteristic (JAFROC) analysis was performed. Seventy-six pulmonary lesions were evaluated. Lesion-based detection rates were: CTex, 77.6%; VIBEin, 53.3%; VIBEex, 51.3%; and Dixon, 22.4%. Lobe-based detection rates were: CTex, 89.6%; VIBEin, 58.3%; VIBEex, 60.4%; and Dixon, 31.3%. In contrast to CT, inspiration versus expiration did not alter diagnostic performance in VIBE sequences. Diagnostic confidence was best for VIBEin and CTex and decreased in VIBEex and Dixon (1.2 ± 0.6; 1.2 ± 0.7; 1.5 ± 0.9; 1.7 ± 1.1, respectively). The JAFROC figure-of-merit of Dixon was significantly lower. All patients with malignant lesions were identified by CTex, VIBEin, and VIBEex, while 3 patients were false-negative in Dixon. Fast T1-weighted VIBE sequences allow for identification of patients with malignant pulmonary lesions. The Dixon sequence is not recommended for lung nodule evaluation in oncologic MR/PET patients. In contrast to CT, inspiration versus

  7. Diagnosing Lung Nodules on Oncologic MR/PET Imaging: Comparison of Fast T1-Weighted Sequences and Influence of Image Acquisition in Inspiration and Expiration Breath-Hold

    Energy Technology Data Exchange (ETDEWEB)

    Schwenzer, Nina F.; Seith, Ferdinand; Gatidis, Sergios [Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen 72076 (Germany); Brendle, Cornelia [Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen 72076 (Germany); Department of Diagnostic and Interventional Neuroradiology, University Hospital of Tuebingen, Tuebingen 72076 (Germany); Schmidt, Holger; Pfannenberg, Christina A. [Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen 72076 (Germany); Fougère, Christian la [Department of Nuclear Medicine, University Hospital of Tuebingen, Tuebingen 72076 (Germany); Nikolaou, Konstantin; Schraml, Christina [Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen 72076 (Germany)

    2016-11-01

    First, to investigate the diagnostic performance of fast T1-weighted sequences for lung nodule evaluation in oncologic magnetic resonance (MR)/positron emission tomography (PET). Second, to evaluate the influence of image acquisition in inspiration and expiration breath-hold on diagnostic performance. The study was approved by the local Institutional Review Board. PET/CT and MR/PET of 44 cancer patients were evaluated by 2 readers. PET/CT included lung computed tomography (CT) scans in inspiration and expiration (CTin, CTex). MR/PET included Dixon sequence for attenuation correction and fast T1-weighted volumetric interpolated breath-hold examination (VIBE) sequences (volume interpolated breath-hold examination acquired in inspiration [VIBEin], volume interpolated breath-hold examination acquired in expiration [VIBEex]). Diagnostic performance was analyzed for lesion-, lobe-, and size-dependence. Diagnostic confidence was evaluated (4-point Likert-scale; 1 = high). Jackknife alternative free-response receiver-operating characteristic (JAFROC) analysis was performed. Seventy-six pulmonary lesions were evaluated. Lesion-based detection rates were: CTex, 77.6%; VIBEin, 53.3%; VIBEex, 51.3%; and Dixon, 22.4%. Lobe-based detection rates were: CTex, 89.6%; VIBEin, 58.3%; VIBEex, 60.4%; and Dixon, 31.3%. In contrast to CT, inspiration versus expiration did not alter diagnostic performance in VIBE sequences. Diagnostic confidence was best for VIBEin and CTex and decreased in VIBEex and Dixon (1.2 ± 0.6; 1.2 ± 0.7; 1.5 ± 0.9; 1.7 ± 1.1, respectively). The JAFROC figure-of-merit of Dixon was significantly lower. All patients with malignant lesions were identified by CTex, VIBEin, and VIBEex, while 3 patients were false-negative in Dixon. Fast T1-weighted VIBE sequences allow for identification of patients with malignant pulmonary lesions. The Dixon sequence is not recommended for lung nodule evaluation in oncologic MR/PET patients. In contrast to CT, inspiration versus

  8. The Agile Rapid Global Combat Support (ARGCS) System: A Cost and Benefit Analysis of Including the ARGCS Technologies in the Acquisition of the Enhanced Consolidated Support System (ECASS)

    Science.gov (United States)

    2007-12-01

    Franck and Carmelita Troy in January 2007. Revised in May of 2007, this interim BCA, based on the data then available, offered an assessment of the...www.drivedemand.com/roipart1.html Franck, Raymond and Carmelita Troy, Agile Rapid Global Combat Support, Business Case Analysis, Version 1.0. Naval

  9. Digital radiography image quality: image processing and display.

    Science.gov (United States)

    Krupinski, Elizabeth A; Williams, Mark B; Andriole, Katherine; Strauss, Keith J; Applegate, Kimberly; Wyatt, Margaret; Bjork, Sandra; Seibert, J Anthony

    2007-06-01

    This article on digital radiography image processing and display is the second of two articles written as part of an intersociety effort to establish image quality standards for digital and computed radiography. The topic of the other paper is digital radiography image acquisition. The articles were developed collaboratively by the ACR, the American Association of Physicists in Medicine, and the Society for Imaging Informatics in Medicine. Increasingly, medical imaging and patient information are being managed using digital data during acquisition, transmission, storage, display, interpretation, and consultation. The management of data during each of these operations may have an impact on the quality of patient care. These articles describe what is known to improve image quality for digital and computed radiography and to make recommendations on optimal acquisition, processing, and display. The practice of digital radiography is a rapidly evolving technology that will require timely revision of any guidelines and standards.

  10. [Rapid Identification of Epicarpium Citri Grandis via Infrared Spectroscopy and Fluorescence Spectrum Imaging Technology Combined with Neural Network].

    Science.gov (United States)

    Pan, Sha-sha; Huang, Fu-rong; Xiao, Chi; Xian, Rui-yi; Ma, Zhi-guo

    2015-10-01

    To explore rapid reliable methods for detection of Epicarpium citri grandis (ECG), the experiment using Fourier Transform Attenuated Total Reflection Infrared Spectroscopy (FTIR/ATR) and Fluorescence Spectrum Imaging Technology combined with Multilayer Perceptron (MLP) Neural Network pattern recognition, for the identification of ECG, and the two methods are compared. Infrared spectra and fluorescence spectral images of 118 samples, 81 ECG and 37 other kinds of ECG, are collected. According to the differences in tspectrum, the spectra data in the 550-1 800 cm(-1) wavenumber range and 400-720 nm wavelength are regarded as the study objects of discriminant analysis. Then principal component analysis (PCA) is applied to reduce the dimension of spectroscopic data of ECG and MLP Neural Network is used in combination to classify them. During the experiment were compared the effects of different methods of data preprocessing on the model: multiplicative scatter correction (MSC), standard normal variable correction (SNV), first-order derivative(FD), second-order derivative(SD) and Savitzky-Golay (SG). The results showed that: after the infrared spectra data via the Savitzky-Golay (SG) pretreatment through the MLP Neural Network with the hidden layer function as sigmoid, we can get the best discrimination of ECG, the correct percent of training set and testing set are both 100%. Using fluorescence spectral imaging technology, corrected by the multiple scattering (MSC) results in the pretreatment is the most ideal. After data preprocessing, the three layers of the MLP Neural Network of the hidden layer function as sigmoid function can get 100% correct percent of training set and 96.7% correct percent of testing set. It was shown that the FTIR/ATR and fluorescent spectral imaging technology combined with MLP Neural Network can be used for the identification study of ECG and has the advantages of rapid, reliable effect.

  11. A rapid ex vivo tissue model for optimising drug detection and ionisation in MALDI imaging studies.

    Science.gov (United States)

    Huber, K; Aichler, M; Sun, N; Buck, A; Li, Z; Fernandez, I E; Hauck, S M; Zitzelsberger, H; Eickelberg, O; Janssen, K P; Keller, U; Walch, A

    2014-10-01

    The aim of this study was to establish an ex vivo model for a faster optimisation of sample preparation procedures, for example matrix choice, in matrix-assisted laser desorption/ionisation (MALDI) drug imaging studies. The ionisation properties of four drugs, afatinib, erlotinib, irinotecan and pirfenidone, were determined in an ex vivo tissue experiment by spotting decreasing dilution series onto liver sections. Hereby, the drug signals were distinctly detectable using different matrix compounds, which allowed the selection of the optimal matrix for each drug. The analysis of afatinib and erlotinib yielded high drug signals with α-cyano-4-hydroxycinnamic acid matrix, whereas 2,3-dihydroxybenzoic acid was identified as optimal matrix for irinotecan and pirfenidone detection. Our method was validated by a MALDI drug imaging approach of in vivo treated mouse tissue resulting in corresponding findings, indicating the spotting method as an appropriate approach to determine the matrix of choice. The present study shows the accordance between the detection of ex vivo spotted drugs and in vivo administered drugs by MALDI-TOF and MALDI-FT-ICR imaging, which has not been demonstrated so far. Our data suggest the ex vivo tissue spotting method as an easy and reliable model to optimise MALDI imaging measurements and to predict drug detection in tissue sections derived from treated mice prior to the recruitment of laboratory animals, which helps to save animals, time and costs.

  12. How lovebirds maneuver rapidly using super-fast head saccades and image feature stabilization

    NARCIS (Netherlands)

    Kress, Daniel; Bokhorst, Van Evelien; Lentink, David

    2015-01-01

    Diurnal flying animals such as birds depend primarily on vision to coordinate their flight path during goal-directed flight tasks. To extract the spatial structure of the surrounding environment, birds are thought to use retinal image motion (optical flow) that is primarily induced by motion of

  13. TU-AB-BRA-04: Quantitative Radiomics: Sensitivity of PET Textural Features to Image Acquisition and Reconstruction Parameters Implies the Need for Standards

    Energy Technology Data Exchange (ETDEWEB)

    Nyflot, MJ; Yang, F; Byrd, D; Bowen, SR; Sandison, GA; Kinahan, PE [University of Washington, Seattle, WA (United States)

    2015-06-15

    Purpose: Despite increased use of heterogeneity metrics for PET imaging, standards for metrics such as textural features have yet to be developed. We evaluated the quantitative variability caused by image acquisition and reconstruction parameters on PET textural features. Methods: PET images of the NEMA IQ phantom were simulated with realistic image acquisition noise. 35 features based on intensity histograms (IH), co-occurrence matrices (COM), neighborhood-difference matrices (NDM), and zone-size matrices (ZSM) were evaluated within lesions (13, 17, 22, 28, 33 mm diameter). Variability in metrics across 50 independent images was evaluated as percent difference from mean for three phantom girths (850, 1030, 1200 mm) and two OSEM reconstructions (2 iterations, 28 subsets, 5 mm FWHM filtration vs 6 iterations, 28 subsets, 8.6 mm FWHM filtration). Also, patient sample size to detect a clinical effect of 30% with Bonferroni-corrected α=0.001 and 95% power was estimated. Results: As a class, NDM features demonstrated greatest sensitivity in means (5–50% difference for medium girth and reconstruction comparisons and 10–100% for large girth comparisons). Some IH features (standard deviation, energy, entropy) had variability below 10% for all sensitivity studies, while others (kurtosis, skewness) had variability above 30%. COM and ZSM features had complex sensitivities; correlation, energy, entropy (COM) and zone percentage, short-zone emphasis, zone-size non-uniformity (ZSM) had variability less than 5% while other metrics had differences up to 30%. Trends were similar for sample size estimation; for example, coarseness, contrast, and strength required 12, 38, and 52 patients to detect a 30% effect for the small girth case but 38, 88, and 128 patients in the large girth case. Conclusion: The sensitivity of PET textural features to image acquisition and reconstruction parameters is large and feature-dependent. Standards are needed to ensure that prospective trials

  14. Active machine learning for rapid landslide inventory mapping with VHR satellite images (Invited)

    Science.gov (United States)

    Stumpf, A.; Lachiche, N.; Malet, J.; Kerle, N.; Puissant, A.

    2013-12-01

    VHR satellite images have become a primary source for landslide inventory mapping after major triggering events such as earthquakes and heavy rainfalls. Visual image interpretation is still the prevailing standard method for operational purposes but is time-consuming and not well suited to fully exploit the increasingly better supply of remote sensing data. Recent studies have addressed the development of more automated image analysis workflows for landslide inventory mapping. In particular object-oriented approaches that account for spatial and textural image information have been demonstrated to be more adequate than pixel-based classification but manually elaborated rule-based classifiers are difficult to adapt under changing scene characteristics. Machine learning algorithm allow learning classification rules for complex image patterns from labelled examples and can be adapted straightforwardly with available training data. In order to reduce the amount of costly training data active learning (AL) has evolved as a key concept to guide the sampling for many applications. The underlying idea of AL is to initialize a machine learning model with a small training set, and to subsequently exploit the model state and data structure to iteratively select the most valuable samples that should be labelled by the user. With relatively few queries and labelled samples, an AL strategy yields higher accuracies than an equivalent classifier trained with many randomly selected samples. This study addressed the development of an AL method for landslide mapping from VHR remote sensing images with special consideration of the spatial distribution of the samples. Our approach [1] is based on the Random Forest algorithm and considers the classifier uncertainty as well as the variance of potential sampling regions to guide the user towards the most valuable sampling areas. The algorithm explicitly searches for compact regions and thereby avoids a spatially disperse sampling pattern

  15. PET/MR - a rapidly growing technique of imaging in oncology and neurology.

    Science.gov (United States)

    Sałyga, Alicja; Guzikowska-Ruszkowska, Izabela; Czepczyński, Rafał; Ruchała, Marek

    2016-01-01

    The combination of positron emission tomography (PET) and magnetic resonance (MR) has become a subject of interest for researchers in the recent several years. Positron emission tomography in combination with magnetic resonance (PET/MR) is the most recent imaging technique classified in the so called hybrid systems category. This review briefly discusses the development history of PET/MR scanners, the principle of their operation, of tandem systems, as well as fully integrated devices. Further, it summarizes recent reports on the application of PET/MR scans and their possible future role in oncological and non-oncological diagnostics. Recent reports regarding the application of PET/MR scanners show huge potential of simultaneously received images, which exceed the advantages of either of those scans used separately. However, the results so far remain uncertain and require further investigations, especially in terms of clinical studies, not only for scientific purposes.

  16. 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.

  17. Recent advances in rapid and non-destructive assessment of meat quality using hyperspectral imaging

    Science.gov (United States)

    Tao, Feifei; Ngadi, Michael

    2016-05-01

    Meat is an important food item in human diet. Its production and consumption has greatly increased in the last decades with the development of economies and improvement of peoples' living standards. However, most of the traditional methods for evaluation of meat quality are time-consuming, laborious, inconsistent and destructive to samples, which make them not appropriate for a fast-paced production and processing environment. Development of innovative and non-destructive optical sensing techniques to facilitate simple, fast, and accurate evaluation of quality are attracting increasing attention in the food industry. Hyperspectral imaging is one of the promising techniques. It integrates the combined merits of imaging and spectroscopic techniques. This paper provides a comprehensive review on recent advances in evaluation of the important quality attributes of meat including color, marbling, tenderness, pH, water holding capacity, and also chemical composition attributes such as moisture content, protein content and fat content in pork, beef and lamb. In addition, the future potential applications and trends of hyperspectral imaging are also discussed in this paper.

  18. Rapid image recognition of body parts scanned in computed tomography datasets.

    Science.gov (United States)

    Dicken, Volker; Lindow, B; Bornemann, L; Drexl, J; Nikoubashman, A; Peitgen, H-O

    2010-09-01

    Automatic CT dataset classification is important to efficiently create reliable database annotations, especially when large collections of scans must be analyzed. An automated segmentation and labeling algorithm was developed based on a fast patient segmentation and extraction of statistical density class features from the CT data. The method also delivers classifications of image noise level and patient size. The approach is based on image information only and uses an approximate patient contour detection and statistical features of the density distribution. These are obtained from a slice-wise analysis of the areas filled by various materials related to certain density classes and the spatial spread of each class. The resulting families of curves are subsequently classified using rules derived from knowledge about features of the human anatomy. The method was successfully applied to more than 5,000 CT datasets. Evaluation was performed via expert visual inspection of screenshots showing classification results and detected characteristic positions along the main body axis. Accuracy per body region was very satisfactory in the trunk (lung/liver >99.5% detection rate, presence of abdomen >97% or pelvis >95.8%) improvements are required for zoomed scans. The method performed very reliably. A test on 1,860 CT datasets collected from an oncological trial showed that the method is feasible, efficient, and is promising as an automated tool for image post-processing.

  19. Time-gated FRET nanoassemblies for rapid and sensitive intra- and extracellular fluorescence imaging.

    Science.gov (United States)

    Afsari, Hamid Samareh; Cardoso Dos Santos, Marcelina; Lindén, Stina; Chen, Ting; Qiu, Xue; van Bergen En Henegouwen, Paul M P; Jennings, Travis L; Susumu, Kimihiro; Medintz, Igor L; Hildebrandt, Niko; Miller, Lawrence W

    2016-06-01

    Time-gated Förster resonance energy transfer (FRET) using the unique material combination of long-lifetime terbium complexes (Tb) and semiconductor quantum dots (QDs) provides many advantages for highly sensitive and multiplexed biosensing. Although time-gated detection can efficiently suppress sample autofluorescence and background fluorescence from directly excited FRET acceptors, Tb-to-QD FRET has rarely been exploited for biomolecular imaging. We demonstrate Tb-to-QD time-gated FRET nanoassemblies that can be applied for intra- and extracellular imaging. Immunostaining of different epitopes of the epidermal growth factor receptor (EGFR) with Tb- and QD-conjugated antibodies and nanobodies allowed for efficient Tb-to-QD FRET on A431 cell membranes. The broad usability of Tb-to-QD FRET was further demonstrated by intracellular Tb-to-QD FRET and Tb-to-QD-to-dye FRET using microinjection as well as cell-penetrating peptide-mediated endocytosis with HeLa cells. Effective brightness enhancement by FRET from several Tb to the same QD, the use of low nanomolar concentrations, and the quick and sensitive detection void of FRET acceptor background fluorescence are important advantages for advanced intra- and extracellular imaging of biomolecular interactions.

  20. MR Diffusion Tensor Imaging Detects Rapid Microstructural Changes in Amygdala and Hippocampus Following Fear Conditioning in Mice

    Science.gov (United States)

    Ding, Abby Y.; Li, Qi; Zhou, Iris Y.; Ma, Samantha J.; Tong, Gehua; McAlonan, Grainne M.; Wu, Ed X.

    2013-01-01

    Background Following fear conditioning (FC), ex vivo evidence suggests that early dynamics of cellular and molecular plasticity in amygdala and hippocampal circuits mediate responses to fear. Such altered dynamics in fear circuits are thought to be etiologically related to anxiety disorders including posttraumatic stress disorder (PTSD). Consistent with this, neuroimaging studies of individuals with established PTSD in the months after trauma have revealed changes in brain regions responsible for processing fear. However, whether early changes in fear circuits can be captured in vivo is not known. Methods We hypothesized that in vivo magnetic resonance diffusion tensor imaging (DTI) would be sensitive to rapid microstructural changes elicited by FC in an experimental mouse PTSD model. We employed a repeated measures paired design to compare in vivo DTI measurements before, one hour after, and one day after FC-exposed mice (n = 18). Results Using voxel-wise repeated measures analysis, fractional anisotropy (FA) significantly increased then decreased in amygdala, decreased then increased in hippocampus, and was increasing in cingulum and adjacent gray matter one hour and one day post-FC respectively. These findings demonstrate that DTI is sensitive to early changes in brain microstructure following FC, and that FC elicits distinct, rapid in vivo responses in amygdala and hippocampus. Conclusions Our results indicate that DTI can detect rapid microstructural changes in brain regions known to mediate fear conditioning in vivo. DTI indices could be explored as a translational tool to capture potential early biological changes in individuals at risk for developing PTSD. PMID:23382811

  1. Rapid Stereomicroscopic Imaging of HER2 Overexpression in Ex Vivo Breast Tissue Using Topically Applied Silica-Based Gold Nanoshells

    Directory of Open Access Journals (Sweden)

    Lissett R. Bickford

    2012-01-01

    Full Text Available Tumor margin detection for patients undergoing breast conservation surgery primarily occurs postoperatively. Previously, we demonstrated that gold nanoshells rapidly enhance contrast of HER2 overexpression in ex vivo tissue sections. Our ultimate objective, however, is to discern HER2 overexpressing tissue from normal tissue in whole, nonsectioned, specimens to facilitate rapid diagnoses. Here, we use targeted nanoshells to quickly and effectively visualize HER2 receptor expression in intact ex vivo human breast tissue specimens. Punch biopsies of human breast tissue were analyzed after a brief 5-minute incubation with and without HER2-targeted silica-gold nanoshells using two-photon microscopy and stereomicroscopy. Labeling was subsequently verified using reflectance confocal microscopy, darkfield hyperspectral imaging, and immunohistochemistry to confirm levels of HER2 expression. Our results suggest that anti-HER2 nanoshells used in tandem with a near-infrared reflectance confocal microscope and a standard stereomicroscope may potentially be used to discern HER2-overexpressing cancerous tissue from normal tissue in near real time and offer a rapid supplement to current diagnostic techniques.

  2. Rapidly updated hyperspectral sounding and imaging data for severe storm prediction

    Science.gov (United States)

    Bingham, Gail; Jensen, Scott; Elwell, John; Cardon, Joel; Crain, David; Huang, Hung-Lung (Allen); Smith, William L.; Revercomb, Hank E.; Huppi, Ronald J.

    2013-09-01

    Several studies have shown that a geostationary hyperspectral imager/sounder can provide the most significant value increase in short term, regional numerical prediction weather models over a range of other options. In 1998, the Geostationary Imaging Fourier Transform Spectrometer (GIFTS) proposal was selected by NASA as the New Millennium Earth Observation 3 program over several other geostationary instrument development proposals. After the EO3 GIFTS flight demonstration program was changed to an Engineering Development Unit (EDU) due to funding limitations by one of the partners, the EDU was subjected to flight-like thermal vacuum calibration and testing and successfully validated the breakthrough technologies needed to make a successful observatory. After several government stops and starts, only EUMETSAT's Meteosat Third Generation (MTG-S) sounder is in operational development. Recently, a commercial partnership has been formed to fill the significant data gap. AsiaSat has partnered with GeoMetWatch (GMW)1 to fund the development and launch of the Sounding and Tracking Observatory for Regional Meteorology (STORMTM) sensor, a derivative of the Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) EDU that was designed, built, and tested by Utah State University (USU). STORMTM combines advanced technologies to observe surface thermal properties, atmospheric weather, and chemistry variables in four dimensions to provide high vertical resolution temperature and moisture sounding information, with the fourth dimension (time) provided by the geosynchronous satellite platform ability to measure a location as often as desired. STORMTM will enhance the polar orbiting imaging and sounding measurements by providing: (1) a direct measure of moisture flux and altitude-resolved water vapor and cloud tracer winds throughout the troposphere, (2) an observation of the time varying atmospheric thermodynamics associated with storm system development, and (3) the

  3. MO-FG-CAMPUS-IeP1-01: Alternative K-Edge Filters for Low-Energy Image Acquisition in Contrast Enhanced Spectral Mammography

    Energy Technology Data Exchange (ETDEWEB)

    Shrestha, S; Vedantham, S; Karellas, A [University of Massachusetts Medical School, Worcester, MA (United States)

    2016-06-15

    Purpose: In Contrast Enhanced Spectral Mammography (CESM), Rh filter is often used during low-energy image acquisition. The potential for using Ag, In and Sn filters, which exhibit K-edge closer to, and just below that of Iodine, instead of the Rh filter, was investigated for the low-energy image acquisition. Methods: Analytical computations of the half-value thickness (HVT) and the photon fluence per mAs (photons/mm2/mAs) for 50µm Rh were compared with other potential K-edge filters (Ag, In and Sn), all with K-absorption edge below that of Iodine. Two strategies were investigated: fixed kVp and filter thickness (50µm for all filters) resulting in HVT variation, and fixed kVp and HVT resulting in variation in Ag, In and Sn thickness. Monte Carlo simulations (GEANT4) were conducted to determine if the scatter-to-primary ratio (SPR) and the point spread function of scatter (scatter PSF) differed between Rh and other K-edge filters. Results: Ag, In and Sn filters (50µm thick) increased photon fluence/mAs by 1.3–1.4, 1.8–2, and 1.7–2 at 28-32 kVp compared to 50µm Rh, which could decrease exposure time. Additionally, the fraction of spectra closer to and just below Iodine’s K-edge increased with these filters, which could improve post-subtraction image contrast. For HVT matched to 50µm Rh filtered spectra, the thickness range for Ag, In, and Sn were (41,44)µm, (49,55)µm and (45,53)µm, and increased photon fluence/mAs by 1.5–1.7, 1.6–2, and 1.6–2.2, respectively. Monte Carlo simulations showed that neither the SPR nor the scatter PSF of Ag, In and Sn differed from Rh, indicating no additional detriment due to x-ray scatter. Conclusion: The use of Ag, In and Sn filters for low-energy image acquisition in CESM is potentially feasible and could decrease exposure time and may improve post-subtraction image contrast. Effect of these filters on radiation dose, contrast, noise and associated metrics are being investigated. Funding Support: Supported in

  4. Priming from distractors in rapid serial visual presentation is modulated by image properties and attention.

    Science.gov (United States)

    Harris, Irina M; Benito, Claire T; Dux, Paul E

    2010-12-01

    We investigated distractor processing in a dual-target rapid serial visual presentation (RSVP) task containing familiar objects, by measuring repetition priming from a priming distractor (PD) to Target 2 (T2). Priming from a visually identical PD was contrasted with priming from a PD in a different orientation from T2. We also tested the effect of attention on distractor processing, by placing the PD either within or outside the attentional blink (AB). PDs outside the AB induced positive priming when they were in a different orientation to T2 and no priming, or negative priming, when they were perceptually identical to T2. PDs within the AB induced positive priming regardless of orientation. These findings demonstrate (1) that distractors are processed at multiple levels of representation; (2) that the view-specific representations of distractors are actively suppressed during RSVP; and (3) that this suppression fails in the absence of attention.

  5. Imaging of acute pulmonary embolism using a dual energy CT system with rapid kVp switching: Initial results

    Energy Technology Data Exchange (ETDEWEB)

    Geyer, Lucas L., E-mail: Lucas.Geyer@med.uni-muenchen.de [Department of Clinical Radiology, Medical Center of the University of Munich, Nussbaumstraße 20, 80336 Munich (Germany); Scherr, Michael, E-mail: michael.scherr@med.uni-muenchen.de [Department of Clinical Radiology, Medical Center of the University of Munich, Nussbaumstraße 20, 80336 Munich (Germany); Körner, Markus, E-mail: markus.koerner@med.uni-muenchen.de [Department of Clinical Radiology, Medical Center of the University of Munich, Nussbaumstraße 20, 80336 Munich (Germany); Wirth, Stefan, E-mail: stefan.wirth@med.uni-muenchen.de [Department of Clinical Radiology, Medical Center of the University of Munich, Nussbaumstraße 20, 80336 Munich (Germany); Deak, Paul, E-mail: paul.deak@ge.com [GE Healthcare, Oskar-Schlemmer-Straße 11, 80807 Munich (Germany); Reiser, Maximilian F., E-mail: maximilian.reiser@med.uni-muenchen.de [Department of Clinical Radiology, Medical Center of the University of Munich, Nussbaumstraße 20, 80336 Munich (Germany); Linsenmaier, Ulrich, E-mail: ulrich.linsenmaier@med.uni-muenchen.de [Department of Clinical Radiology, Medical Center of the University of Munich, Nussbaumstraße 20, 80336 Munich (Germany)

    2012-12-15

    Purpose: Computed tomography pulmonary angiography (CTPA) is considered as clinical gold standard for diagnosing pulmonary embolism (PE). Whereas conventional CTPA only offers anatomic information, dual energy CT (DECT) provides functional information on blood volume as surrogate of perfusion by assessing the pulmonary iodine distribution. The purpose of this study was to evaluate the feasibility of lung perfusion imaging using a single-tube DECT scanner with rapid kVp switching. Materials and methods: Fourteen patients with suspicion of acute PE underwent DECT. Two experienced radiologists assessed the CTPA images and lung perfusion maps regarding the presence of PE. The image quality was rated using a semi-quantitative 5-point scale: 1 (=excellent) to 5 (=non-diagnostic). Iodine concentrations were quantified by a ROI analysis. Results: Seventy perfusion defects were identified in 266 lung segments: 13 (19%) were rated as consistent with PE. Five patients had signs of PE at CTPA. All patients with occlusive clots were correctly identified by DECT perfusion maps. On a per patient basis the sensitivity and specificity were 80.0% and 88.9%, respectively, while on a per segment basis it was 40.0% and 97.6%, respectively. None of the patients with a homogeneous perfusion map had an abnormal CTPA. The overall image quality of the perfusion maps was rated with a mean score of 2.6 ± 0.6. There was a significant ventrodorsal gradient of the median iodine concentrations (1.1 mg/cm{sup 3} vs. 1.7 mg/cm{sup 3}). Conclusion: Lung perfusion imaging on a DE CT-system with fast kVp-switching is feasible. DECT might be a helpful adjunct to assess the clinical severity of PE.

  6. Study of the acquisition and reconstruction parameters of myocardial perfusion images in the detection of lesions; Estudo dos parametros de aquisicao e reconstrucao em imagens de perfusao de miocardio na deteccao de lesoes

    Energy Technology Data Exchange (ETDEWEB)

    Favero, Mariana S.; Finatto, Jerusa D.; Friedrich, Barbara Q.; Silva, Ana Maria M., E-mail: mariana.saibt@acad.pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (NIMed/PUCRS), Porto Alegre, RS (Brazil). Nucleo de Pesquisas em Imagens Medicas; Mazzola, Carolina F.S. [Hospital Sao Lucas (HSL/PUCRS), Porto Alegre, RS (Brazil). Servico de Medicina Nuclear

    2012-12-15

    The aim of this paper was to analyze the influence of different acquisition parameters and reconstruction methods used in myocardial SPECT examinations in order to optimize the image of the left ventricle, allowing better visualization of lesions. For this purpose, a study was performed with images acquired on a Philips Forte SPECT equipment with an anthropomorphic phantom with cardiac insert filled with Tc-99m. Acrylic regions, representing cold lesions, were inserted into the lateral septum. The image was evaluated by profile counting, relative contrast and polar map. It was observed that the different parameters and acquisition reconstruction methods do not produce significant visual differences in the resulting images. Quantitatively, the acquisition with 64 projections reconstructed with the iterative method has a higher contrast. (author)

  7. Multichannel microfluidic chip for rapid and reliable trapping and imaging plant-parasitic nematodes

    Science.gov (United States)

    Amrit, Ratthasart; Sripumkhai, Witsaroot; Porntheeraphat, Supanit; Jeamsaksiri, Wutthinan; Tangchitsomkid, Nuchanart; Sutapun, Boonsong

    2013-05-01

    Faster and reliable testing technique to count and identify nematode species resided in plant roots is therefore essential for export control and certification. This work proposes utilizing a multichannel microfluidic chip with an integrated flow-through microfilter to retain the nematodes in a trapping chamber. When trapped, it is rather simple and convenient to capture images of the nematodes and later identify their species by a trained technician. Multiple samples can be tested in parallel using the proposed microfluidic chip therefore increasing number of samples tested per day.

  8. A state-of-the-art pipeline for postmortem CT and MRI visualization: from data acquisition to interactive image interpretation at autopsy.

    Science.gov (United States)

    Persson, Anders; Lindblom, Maria; Jackowski, Christian

    2011-06-01

    The importance of autopsy procedures leading to the establishment of the cause of death is well-known. A recent addition to the autopsy work flow is the possibility of conducting postmortem imaging, in its 3D version also called virtual autopsy (VA), using multidetector computed tomography (MDCT) or magnetic resonance imagining (MRI) data from scans of cadavers displayed with direct volume rendering (DVR) 3D techniques. The use of the data and their workflow are presented. Data acquisition was performed and high quality data-sets with submillimeter precision were acquired. New data acquisition techniques such as dual-energy CT (DECT) and quantitative MRI, then were implemented and provided additional information. Particular findings hardly visualized in conventional autopsy can rather easy be seen at the full body CT, such as air distribution, e.g. pneumothorax, pneumopericardium, air embolism, and wound channels. MRI shows natural deaths such as myocardial infarctions. Interactive visualization of these 3D data-sets can provide valuable insight into the corpses and enables non-invasive diagnostic procedures. In postmortem CT imaging, not being limited by a patient depending radiation dose limit the data-sets can, however, be generated with such a high resolution that they become difficult to handle in today's archive retrieval and interactive visualization systems, specifically in the case of full body scans. To take full advantage of these new technologies the postmortem workflow needs to be tailored to the demands and opportunities that the new technologies allow.

  9. A state-of-the-art pipeline for postmortem CT and MRI visualization: from data acquisition to interactive image interpretation at autopsy

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Anders (Center for Medical Image Science and Visualization (CMIV), Univ. of Linkoeping, Linkoeping (Sweden); Dept. of Radiology of Medical and Health Sciences (IMH), Linkoeping Univ. Hospital, Linkoeping (Sweden)), email: anders.persson@cmiv.liu.se; Lindblom, Maria (Dept. of Radiology of Medical and Health Sciences (IMH), Linkoeping Univ. Hospital, Linkoeping (Sweden)); Jackowski, Christian (Inst. of Legal Medicine, Univ. of Zurich, Zurich (Switzerland))

    2011-06-15

    The importance of autopsy procedures leading to the establishment of the cause of death is well-known. A recent addition to the autopsy work flow is the possibility of conducting postmortem imaging, in its 3D version also called virtual autopsy (VA), using multidetector computed tomography (MDCT) or magnetic resonance imagining (MRI) data from scans of cadavers displayed with direct volume rendering (DVR) 3D techniques. The use of the data and their workflow are presented. Data acquisition was performed and high quality data-sets with submillimeter precision were acquired. New data acquisition techniques such as dual-energy CT (DECT) and quantitative MRI, then were implemented and provided additional information. Particular findings hardly visualized in conventional autopsy can rather easy be seen at the full body CT, such as air distribution, e.g. pneumothorax, pneumopericardium, air embolism, and wound channels. MRI shows natural deaths such as myocardial infarctions. Interactive visualization of these 3D data-sets can provide valuable insight into the corpses and enables non-invasive diagnostic procedures. In postmortem CT imaging, not being limited by a patient depending radiation dose limit the data-sets can, however, be generated with such a high resolution that they become difficult to handle in today's archive retrieval and interactive visualization systems, specifically in the case of full body scans. To take full advantage of these new technologies the postmortem workflow needs to be tailored to the demands and opportunities that the new technologies allow

  10. StripeSTEM, a technique for the isochronous acquisition of high angle annular dark-field images and monolayer resolved electron energy loss spectra

    Energy Technology Data Exchange (ETDEWEB)

    Heidelmann, M., E-mail: m.heidelmann@fz-juelich.de [Institute of Solid State Research and Ernst Ruska Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany); Barthel, J.; Houben, L. [Institute of Solid State Research and Ernst Ruska Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany)

    2009-11-15

    A technique capable of producing monolayer resolved electron energy loss (EEL) spectroscopy data along one direction in crystal structures is introduced. Unambiguous assignment of EEL spectra to atomic planes is possible via the execution of high angle annular dark-field (HAADF) imaging and EEL spectrum acquisition in parallel. The recording of instrumental instabilities in the HAADF image during the measurement enables a proper quantification by virtue of post-acquisition correction. Compared to the conventional line profile technique a dose reduction by several orders of magnitude can be achieved. The technique is applied to bulk SrTiO{sub 3} and ZnO:In{sub 2}O{sub 3} in order to explore its capabilities and limits. Monolayer resolution was achieved for the Ti-L{sub 23} and In-M{sub 45} core-losses. Multislice calculations were carried out for the purpose of assessing the residual delocalisation of the inelastic signal. Fundamental limits to the resolution are imposed by dynamical dispersion of the electron wave in the crystal combined with the extension of the inelastic potential. In the present case, owing to the requirement of a high beam current, the geometrical probe size cannot be neglected when compared to the width of an inelastic scattering potential.

  11. Graphics Processing Unit (GPU) implementation of image processing algorithms to improve system performance of the Control, Acquisition, Processing, and Image Display System (CAPIDS) of the Micro-Angiographic Fluoroscope (MAF).

    Science.gov (United States)

    Vasan, S N Swetadri; Ionita, Ciprian N; Titus, A H; Cartwright, A N; Bednarek, D R; Rudin, S

    2012-02-23

    We present the image processing upgrades implemented on a Graphics Processing Unit (GPU) in the Control, Acquisition, Processing, and Image Display System (CAPIDS) for the custom Micro-Angiographic Fluoroscope (MAF) detector. Most of the image processing currently implemented in the CAPIDS system is pixel independent; that is, the operation on each pixel is the same and the operation on one does not depend upon the result from the operation on the other, allowing the entire image to be processed in parallel. GPU hardware was developed for this kind of massive parallel processing implementation. Thus for an algorithm which has a high amount of parallelism, a GPU implementation is much faster than a CPU implementation. The image processing algorithm upgrades implemented on the CAPIDS system include flat field correction, temporal filtering, image subtraction, roadmap mask generation and display window and leveling. A comparison between the previous and the upgraded version of CAPIDS has been presented, to demonstrate how the improvement is achieved. By performing the image processing on a GPU, significant improvements (with respect to timing or frame rate) have been achieved, including stable operation of the system at 30 fps during a fluoroscopy run, a DSA run, a roadmap procedure and automatic image windowing and leveling during each frame.

  12. Including secondary illumination in seismic acquisition design

    NARCIS (Netherlands)

    Kumar, A.; Blacquière, G.

    2013-01-01

    A subsurface image obtained from seismic data is influenced by the acquisition geometry, as it contains an acquisition foot-print which can obscure the true reflection response of the subsurface. Hence, the acquisition geometry should be designed in such a way that it allows high-quality images and

  13. A method for rapid quantitative assessment of biofilms with biomolecular staining and image analysis.

    Science.gov (United States)

    Larimer, Curtis; Winder, Eric; Jeters, Robert; Prowant, Matthew; Nettleship, Ian; Addleman, Raymond Shane; Bonheyo, George T

    2016-01-01

    The accumulation of bacteria in surface-attached biofilms can be detrimental to human health, dental hygiene, and many industrial processes. Natural biofilms are soft and often transparent, and they have heterogeneous biological composition and structure over micro- and macroscales. As a result, it is challenging to quantify the spatial distribution and overall intensity of biofilms. In this work, a new method was developed to enhance the visibility and quantification of bacterial biofilms. First, broad-spectrum biomolecular staining was used to enhance the visibility of the cells, nucleic acids, and proteins that make up biofilms. Then, an image analysis algorithm was developed to objectively and quantitatively measure biofilm accumulation from digital photographs and results were compared to independent measurements of cell density. This new method was used to quantify the growth intensity of Pseudomonas putida biofilms as they grew over time. This method is simple and fast, and can quantify biofilm growth over a large area with approximately the same precision as the more laborious cell counting method. Stained and processed images facilitate assessment of spatial heterogeneity of a biofilm across a surface. This new approach to biofilm analysis could be applied in studies of natural, industrial, and environmental biofilms.

  14. Rapid simulation of X-ray transmission imaging for baggage inspection via GPU-based ray-tracing

    Science.gov (United States)

    Gong, Qian; Stoian, Razvan-Ionut; Coccarelli, David S.; Greenberg, Joel A.; Vera, Esteban; Gehm, Michael E.

    2018-01-01

    We present a pipeline that rapidly simulates X-ray transmission imaging for arbitrary system architectures using GPU-based ray-tracing techniques. The purpose of the pipeline is to enable statistical analysis of threat detection in the context of airline baggage inspection. As a faster alternative to Monte Carlo methods, we adopt a deterministic approach for simulating photoelectric absorption-based imaging. The highly-optimized NVIDIA OptiX API is used to implement ray-tracing, greatly speeding code execution. In addition, we implement the first hierarchical representation structure to determine the interaction path length of rays traversing heterogeneous media described by layered polygons. The accuracy of the pipeline has been validated by comparing simulated data with experimental data collected using a heterogenous phantom and a laboratory X-ray imaging system. On a single computer, our approach allows us to generate over 400 2D transmission projections (125 × 125 pixels per frame) per hour for a bag packed with hundreds of everyday objects. By implementing our approach on cloud-based GPU computing platforms, we find that the same 2D projections of approximately 3.9 million bags can be obtained in a single day using 400 GPU instances, at a cost of only 0.001 per bag.

  15. Cardiac Light-Sheet Fluorescent Microscopy for Multi-Scale and Rapid Imaging of Architecture and Function

    Science.gov (United States)

    Fei, Peng; Lee, Juhyun; Packard, René R. Sevag; Sereti, Konstantina-Ioanna; Xu, Hao; Ma, Jianguo; Ding, Yichen; Kang, Hanul; Chen, Harrison; Sung, Kevin; Kulkarni, Rajan; Ardehali, Reza; Kuo, C.-C. Jay; Xu, Xiaolei; Ho, Chih-Ming; Hsiai, Tzung K.

    2016-03-01

    Light Sheet Fluorescence Microscopy (LSFM) enables multi-dimensional and multi-scale imaging via illuminating specimens with a separate thin sheet of laser. It allows rapid plane illumination for reduced photo-damage and superior axial resolution and contrast. We hereby demonstrate cardiac LSFM (c-LSFM) imaging to assess the functional architecture of zebrafish embryos with a retrospective cardiac synchronization algorithm for four-dimensional reconstruction (3-D space + time). By combining our approach with tissue clearing techniques, we reveal the entire cardiac structures and hypertrabeculation of adult zebrafish hearts in response to doxorubicin treatment. By integrating the resolution enhancement technique with c-LSFM to increase the resolving power under a large field-of-view, we demonstrate the use of low power objective to resolve the entire architecture of large-scale neonatal mouse hearts, revealing the helical orientation of individual myocardial fibers. Therefore, our c-LSFM imaging approach provides multi-scale visualization of architecture and function to drive cardiovascular research with translational implication in congenital heart diseases.

  16. Rapid estimation of cartilage T2 with reduced T1 sensitivity using double echo steady state imaging.

    Science.gov (United States)

    Heule, Rahel; Ganter, Carl; Bieri, Oliver

    2014-03-01

    In principle, double echo steady state (DESS) offers morphological and quantitative T2 imaging of cartilage within one single scan. However, accurate T2 estimation is hampered by its prominent T1 dependency in the limit of low flip angles, generally used to image cartilage morphology, as for the osteoarthritis initiative. A new postprocessing approach is introduced to overcome this T1-related bias for rapid DESS-based T2 quantification in the low flip angle regime. Based on a rough global T1 estimator and a golden section search, T2 is extracted from the ratio of the two echoes acquired with DESS. The new relaxometry method is evaluated from simulations and in vivo 3D measurements of the knee joint at 3T. A pronounced reduction in the T1-related bias of DESS-T2 estimation and increased zonal variation in T2 between deep and superficial cartilage layers are observed. The improvement becomes particularly evident in the range of low flip angles (α estimate, the reliability of DESS-T2 quantification can be considerably increased. The results emphasize the potential of DESS to fuse accurate quantitative T2 and morphological imaging of the musculoskeletal system within one single scan. Copyright © 2013 Wiley Periodicals, Inc.

  17. Development of an AutoFlat program for the acquisition of effective flat images in the automated observation system

    Directory of Open Access Journals (Sweden)

    Joh-Na Yoon

    2013-12-01

    Full Text Available The purpose of this study is to develop an observation program for obtaining effective flat images that are necessary for photometric observation. The development of the program was achieved by improving the existing method for obtaining twilight flat images. The existing method for obtaining twilight flat images acquires flat images by observing the sky light after sunset or light before sunrise. The decision of when to observe flat images at each night is solely dependent on the judgment of an observer, and thus the obtained flat images for particular nights may not be clean. Especially, in the case of the observatories where an automated observation system is in operation, there is a difficulty that an observer should pay attention during sunrise and sunset in order to obtain flat images. In this study, a computer program is developed to improve this inconvenience and to efficiently perform photometric observation in the observatories where an automated observation system is applied. This program can obtain flat images by calculating the time for obtaining flat images automatically and the exposure time using a numerically calculated function. When obtaining twilight flat images at dusk and at dawn, the developed program performs automated observation and provides effective flat images by acquiring appropriate exposure time considering the sunrise and sunset times that vary depending on the day of observation. The code for performing this task was added to Obs Tool II (Yoon et al. 2006, which is the automated observation system of the Chungbuk National University Observatory, and the usefulness of the developed program was examined by performing an actual automated observation. If this program is applied to other observatories where automated observation is in operation, it is expected that stable and highquality flat images could be obtained, which can be used for the pre-processing of photometric observation data.

  18. Highly accelerated acquisition and homogeneous image reconstruction with rotating RF coil array at 7T-A phantom based study.

    Science.gov (United States)

    Li, Mingyan; Zuo, Zhentao; Jin, Jin; Xue, Rong; Trakic, Adnan; Weber, Ewald; Liu, Feng; Crozier, Stuart

    2014-03-01

    Parallel imaging (PI) is widely used for imaging acceleration by means of coil spatial sensitivities associated with phased array coils (PACs). By employing a time-division multiplexing technique, a single-channel rotating radiofrequency coil (RRFC) provides an alternative method to reduce scan time. Strategically combining these two concepts could provide enhanced acceleration and efficiency. In this work, the imaging acceleration ability and homogeneous image reconstruction strategy of 4-element rotating radiofrequency coil array (RRFCA) was numerically investigated and experimental validated at 7T with a homogeneous phantom. Each coil of RRFCA was capable of acquiring a large number of sensitivity profiles, leading to a better acceleration performance illustrated by the improved geometry-maps that have lower maximum values and more uniform distributions compared to 4- and 8-element stationary arrays. A reconstruction algorithm, rotating SENSitivity Encoding (rotating SENSE), was proposed to provide image reconstruction. Additionally, by optimally choosing the angular sampling positions and transmit profiles under the rotating scheme, phantom images could be faithfully reconstructed. The results indicate that, the proposed technique is able to provide homogeneous reconstructions with overall higher and more uniform signal-to-noise ratio (SNR) distributions at high reduction factors. It is hoped that, by employing the high imaging acceleration and homogeneous imaging reconstruction ability of RRFCA, the proposed method will facilitate human imaging for ultra high field MRI. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Optimizing the Attitude Control of Small Satellite Constellations for Rapid Response Imaging

    Science.gov (United States)

    Nag, S.; Li, A.

    2016-12-01

    Distributed Space Missions (DSMs) such as formation flight and constellations, are being recognized as important solutions to increase measurement samples over space and time. Given the increasingly accurate attitude control systems emerging in the commercial market, small spacecraft now have the ability to slew and point within few minutes of notice. In spite of hardware development in CubeSats at the payload (e.g. NASA InVEST) and subsystems (e.g. Blue Canyon Technologies), software development for tradespace analysis in constellation design (e.g. Goddard's TAT-C), planning and scheduling development in single spacecraft (e.g. GEO-CAPE) and aerial flight path optimizations for UAVs (e.g. NASA Sensor Web), there is a gap in open-source, open-access software tools for planning and scheduling distributed satellite operations in terms of pointing and observing targets. This paper will demonstrate results from a tool being developed for scheduling pointing operations of narrow field-of-view (FOV) sensors over mission lifetime to maximize metrics such as global coverage and revisit statistics. Past research has shown the need for at least fourteen satellites to cover the Earth globally everyday using a LandSat-like sensor. Increasing the FOV three times reduces the need to four satellites, however adds image distortion and BRDF complexities to the observed reflectance. If narrow FOV sensors on a small satellite constellation were commanded using robust algorithms to slew their sensor dynamically, they would be able to coordinately cover the global landmass much faster without compensating for spatial resolution or BRDF effects. Our algorithm to optimize constellation satellite pointing is based on a dynamic programming approach under the constraints of orbital mechanics and existing attitude control systems for small satellites. As a case study for our algorithm, we minimize the time required to cover the 17000 Landsat images with maximum signal to noise ratio fall

  20. Rapid acquisition and modulation of colistin-resistance by an extensively drug-resistant Acinetobacter baumannii: case report and review of current literature

    Directory of Open Access Journals (Sweden)

    Jari Intra

    2016-10-01

    Full Text Available Acinetobacter baumannii has emerged as a major cause of healthcare-associated infections. It commonly expresses clinical resistance to multiple antimicrobial agents, and hence, it is considered the paradigm of an extensively drug-resistant (XDR bacterium. XDR A. baumannii is a rapidly emerging pathogen, especially in the intensive care unit (ICU, causing nosocomial infections including sepsis, ventilatorassociated pneumonia, meningitis, peritonitis, urinary tract infection, and central venous catheter-related infection. In the present report, we described an in vivo evolution of A. baumannii strain from a colistinsusceptibility to a colistin-resistance state. A 65-year-old male, who suffered a duodenal ulcer, two days after hospitalization and during the stay in ICU, contracted a pneumonia and peritoneal infection by a carbapenem-resistant A. baumannii strain. After a combination treatment with colistin, vancomycin plus imipenem, and within seven days, the pathogen rapidly evolved in seven days to a pandrug-resistant phenotype. As the antimicrobial treatment was stopped, the A. baumannii isolate changed another time its profile to colistin, becoming newly susceptible, showing a very high level of adaptability to external conditions. We also have reviewed here the current literature on this worryingly public health threat.

  1. Image quality and radiation dose of lower extremity CT angiography using 70 kVp, high pitch acquisition and sinogram-affirmed iterative reconstruction.

    Directory of Open Access Journals (Sweden)

    Li Qi

    Full Text Available OBJECTIVES: The purpose of this study was to assess image quality and radiation dose of lower extremity CT angiography (CTA with 70 kVp, high pitch acquisition and sinogram-affirmed iterative reconstruction (SAFIRE. METHODS: Lower extremity CTAs were performed on 44 patients: 22 patients were examined using protocol A (120 kVp, pitch of 0.85 and 120 ml of contrast agent on a first-generation dual-source CT (120 kVp group and 22 patients were evaluated with protocol B (70 kVp, pitch of 2.2 and 80 ml of contrast agent on a second-generation dual-source CT (70 kVp group. Images from the 120 kVp group were reconstructed with filtered back projection (FBP and images from the 70 kVp group with SAFIRE. The attenuation, image noise, signal-to-noise ratio (SNR and contrast-to-noise ratio (CNR were calculated. Two radiologists subjectively assessed image quality of lower extremity arteries, plantar arterial enhancement and venous contamination of all patients. Radiation dose was compared between the two groups. RESULTS: Higher mean intravascular attenuation was obtained in the 70 kVp group (70 vs. 120 kVp group, 555.4 ± 83.4 HU vs. 300.9 ± 81.4 HU, P0.05. The venous contamination score was 1.5 ± 0.8 for 120 kVp group while no venous contamination was found in 70 kVp group. The inter-observer agreement was moderate to good for both groups (0.515∼1, P<0.001. The effective dose was lower in 70 kVp group (0.3 ± 0.1 mSv than in 120 kVp group (1.6 ± 0.7 mSv(P<0.001. CONCLUSIONS: Lower extremity CTA using 70 kVp, high pitch acquisition and SAFIRE, except increasing imaging noise, allows for lower radiation dose and contrast material volume without compromising image quality.

  2. Rapid imaging, detection and quantification of Giardia lamblia cysts using mobile-phone based fluorescent microscopy and machine learning.

    Science.gov (United States)

    Koydemir, Hatice Ceylan; Gorocs, Zoltan; Tseng, Derek; Cortazar, Bingen; Feng, Steve; Chan, Raymond Yan Lok; Burbano, Jordi; McLeod, Euan; Ozcan, Aydogan

    2015-03-07

    Rapid and sensitive detection of waterborne pathogens in drinkable and recreational water sources is crucial for treating and preventing the spread of water related diseases, especially in resource-limited settings. Here we present a field-portable and cost-effective platform for detection and quantification of Giardia lamblia cysts, one of the most common waterborne parasites, which has a thick cell wall that makes it resistant to most water disinfection techniques including chlorination. The platform consists of a smartphone coupled with an opto-mechanical attachment weighing ~205 g, which utilizes a hand-held fluorescence microscope design aligned with the camera unit of the smartphone to image custom-designed disposable water sample cassettes. Each sample cassette is composed of absorbent pads and mechanical filter membranes; a membrane with 8 μm pore size is used as a porous spacing layer to prevent the backflow of particles to the upper membrane, while the top membrane with 5 μm pore size is used to capture the individual Giardia cysts that are fluorescently labeled. A fluorescence image of the filter surface (field-of-view: ~0.8 cm(2)) is captured and wirelessly transmitted via the mobile-phone to our servers for rapid processing using a machine learning algorithm that is trained on statistical features of Giardia cysts to automatically detect and count the cysts captured on the membrane. The results are then transmitted back to the mobile-phone in less than 2 minutes and are displayed through a smart application running on the phone. This mobile platform, along with our custom-developed sample preparation protocol, enables analysis of large volumes of water (e.g., 10-20 mL) for automated detection and enumeration of Giardia cysts in ~1 hour, including all the steps of sample preparation and analysis. We evaluated the performance of this approach using flow-cytometer-enumerated Giardia-contaminated water samples, demonstrating an average cyst capture

  3. Rapid, semi-automatic fracture and contact mapping for point clouds, images and geophysical data

    Science.gov (United States)

    Thiele, Samuel T.; Grose, Lachlan; Samsu, Anindita; Micklethwaite, Steven; Vollgger, Stefan A.; Cruden, Alexander R.

    2017-12-01

    The advent of large digital datasets from unmanned aerial vehicle (UAV) and satellite platforms now challenges our ability to extract information across multiple scales in a timely manner, often meaning that the full value of the data is not realised. Here we adapt a least-cost-path solver and specially tailored cost functions to rapidly interpolate structural features between manually defined control points in point cloud and raster datasets. We implement the method in the geographic information system QGIS and the point cloud and mesh processing software CloudCompare. Using these implementations, the method can be applied to a variety of three-dimensional (3-D) and two-dimensional (2-D) datasets, including high-resolution aerial imagery, digital outcrop models, digital elevation models (DEMs) and geophysical grids. We demonstrate the algorithm with four diverse applications in which we extract (1) joint and contact patterns in high-resolution orthophotographs, (2) fracture patterns in a dense 3-D point cloud, (3) earthquake surface ruptures of the Greendale Fault associated with the Mw7.1 Darfield earthquake (New Zealand) from high-resolution light detection and ranging (lidar) data, and (4) oceanic fracture zones from bathymetric data of the North Atlantic. The approach improves the consistency of the interpretation process while retaining expert guidance and achieves significant improvements (35-65 %) in digitisation time compared to traditional methods. Furthermore, it opens up new possibilities for data synthesis and can quantify the agreement between datasets and an interpretation.

  4. Evaluation of a multiple spin- and gradient-echo (SAGE) EPI acquisition with SENSE acceleration: applications for perfusion imaging in and outside the brain.

    Science.gov (United States)

    Skinner, Jack T; Robison, Ryan K; Elder, Christopher P; Newton, Allen T; Damon, Bruce M; Quarles, C Chad

    2014-12-01

    Perfusion-based changes in MR signal intensity can occur in response to the introduction of exogenous contrast agents and endogenous tissue properties (e.g. blood oxygenation). MR measurements aimed at capturing these changes often implement single-shot echo planar imaging (ssEPI). In recent years ssEPI readouts have been combined with parallel imaging (PI) to allow fast dynamic multi-slice imaging as well as the incorporation of multiple echoes. A multiple spin- and gradient-echo (SAGE) EPI acquisition has recently been developed to allow measurement of transverse relaxation rate (R2 and R2(*)) changes in dynamic susceptibility contrast (DSC)-MRI experiments in the brain. With SAGE EPI, the use of PI can influence image quality, temporal resolution, and achievable echo times. The effect of PI on dynamic SAGE measurements, however, has not been evaluated. In this work, a SAGE EPI acquisition utilizing SENSE PI and partial Fourier (PF) acceleration was developed and evaluated. Voxel-wise measures of R2 and R2(*) in healthy brain were compared using SAGE EPI and conventional non-EPI multiple echo acquisitions with varying SENSE and PF acceleration. A conservative SENSE factor of 2 with PF factor of 0.73 was found to provide accurate measures of R2 and R2(*) in white (WM) (rR2=[0.55-0.79], rR2*=[0.47-0.71]) and gray (GM) matter (rR2=[0.26-0.59], rR2*=[0.39-0.74]) across subjects. The combined use of SENSE and PF allowed the first dynamic SAGE EPI measurements in muscle, with a SENSE factor of 3 and PF factor of 0.6 providing reliable relaxation rate estimates when compared to multi-echo methods. Application of the optimized SAGE protocol in DSC-MRI of high-grade glioma patients provided T1 leakage-corrected estimates of CBV and CBF as well as mean vessel diameter (mVD) and simultaneous measures of DCE-MRI parameters K(trans) and ve. Likewise, application of SAGE in a muscle reperfusion model allowed dynamic measures of R2', a parameter that has been shown to correlate

  5. Programmatically Optimized SEM Image Acquisition for Measurement of Contamination on Molybdenum Coated Foils from the NASA Genesis Mission

    Science.gov (United States)

    Gil, A.

    2016-12-01

    The NASA Genesis Mission flew high-purity collector materials on a satellite from 2001-2004 to collect a sample of the solar wind. Upon return to Earth, a spacecraft malfunction caused the onboard sample materials to be severely contaminated during the crash landing in the Utah desert. As part of an ongoing effort to decontaminate the collector materials, they are being scanned with a scanning electron microscope (SEM) to determine the amount of dirt and spacecraft debris contaminating the collectors. This effort is underway currently, but we have identified an opportunity to improve the quality of the SEM data collected. At present, many small images are acquired and stitched together to form larger images of Genesis collector pieces, which are then analyzed. The collectors are physically distorted, however, and the imaging method presently used doesn't allow imaging parameters to be adjusted between images to correct for this distortion. In order to improve the quality of the collected imaging, we are developing a program to acquire a focus map of each sample prior to image collection. The program then uses this data to adjust the position of the sample in the SEM to image all sections in focus and at a constant focal length. This is accomplished using the Python programming language, and the programmatic interface built into our Tescan VEGA Scanning Electron Microscope. Our approach, progress to date, and challenges are discussed.

  6. Synthetic Receive Beamforming and Image Acquisition Capabilities Using an 8 x 128 1.75D Array

    DEFF Research Database (Denmark)

    Fernandez, Anna T.; Gammelmark, Kim; Dahl, Jeremy J.

    2003-01-01

    Ultrasound imaging can be improved with higher order arrays through elevation dynamic focusing in future, higher channel count systems. However, modifications to current system hardware could yield increased imaging depth-of-field with 1.75D arrays (arrays with individually addressable elements, ...

  7. A game-based crowdsourcing platform for rapidly training middle and high school students to perform biomedical image analysis

    Science.gov (United States)

    Feng, Steve; Woo, Min-jae; Kim, Hannah; Kim, Eunso; Ki, Sojung; Shao, Lei; Ozcan, Aydogan

    2016-03-01

    We developed an easy-to-use and widely accessible crowd-sourcing tool for rapidly training humans to perform biomedical image diagnostic tasks and demonstrated this platform's ability on middle and high school students in South Korea to diagnose malaria infected red-blood-cells (RBCs) using Giemsa-stained thin blood smears imaged under light microscopes. We previously used the same platform (i.e., BioGames) to crowd-source diagnostics of individual RBC images, marking them as malaria positive (infected), negative (uninfected), or questionable (insufficient information for a reliable diagnosis). Using a custom-developed statistical framework, we combined the diagnoses from both expert diagnosticians and the minimally trained human crowd to generate a gold standard library of malaria-infection labels for RBCs. Using this library of labels, we developed a web-based training and educational toolset that provides a quantified score for diagnosticians/users to compare their performance against their peers and view misdiagnosed cells. We have since demonstrated the ability of this platform to quickly train humans without prior training to reach high diagnostic accuracy as compared to expert diagnosticians. Our initial trial group of 55 middle and high school students has collectively played more than 170 hours, each demonstrating significant improvements after only 3 hours of training games, with diagnostic scores that match expert diagnosticians'. Next, through a national-scale educational outreach program in South Korea we recruited >1660 students who demonstrated a similar performance level after 5 hours of training. We plan to further demonstrate this tool's effectiveness for other diagnostic tasks involving image labeling and aim to provide an easily-accessible and quickly adaptable framework for online training of new diagnosticians.

  8. Cartilage imaging at 3.0T with gradient refocused acquisition in the steady-state (GRASS) and IDEAL fat-water separation.

    Science.gov (United States)

    Kijowski, Richard; Tuite, Michael; Passov, Leo; Shimakawa, Ann; Yu, Huanzhou; Hu, Huanzhou; Reeder, Scott B

    2008-07-01

    To demonstrate the feasibility of evaluating the articular cartilage of the knee joint at 3.0T using gradient refocused acquisition in the steady-state (GRASS) and iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) fat-water separation. Bloch equation simulations and a clinical pilot study (n = 10 knees) were performed to determine the influence of flip angle of the IDEAL-GRASS sequence on the signal-to-noise ratio (SNR) of cartilage and synovial fluid and the contrast-to-noise ratio (CNR) between cartilage and synovial fluid at 3.0T. The optimized IDEAL-GRASS sequence was then performed on 30 symptomatic patients as part of the routine 3.0T knee MRI examination at our institution. The optimal flip angle was 50 degrees for IDEAL-GRASS cartilage imaging, which maximized contrast between cartilage and synovial fluid. The IDEAL-GRASS sequence consistently produced high-quality fat- and water-separated images of the knee with bright synovial fluid and 0.39 x 0.67 x 1.0 mm resolution in 5 minutes. IDEAL-GRASS images had high cartilage SNR and high contrast between cartilage and adjacent joint structures. The IDEAL-GRASS sequence provided excellent visualization of cartilage lesions in all patients. The IDEAL-GRASS sequence shows promise for use as a morphologic cartilage imaging sequence at 3.0T. (c) 2008 Wiley-Liss, Inc.

  9. Dural attachment of intracranial meningiomas: evaluation with contrast-enhanced three-dimensional fast imaging with steady-state acquisition (FIESTA) at 3 T

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Junkoh; Takahashi, Mayu; Aoyama, Yuichi; Soejima, Yoshiteru; Saito, Takeshi; Akiba, Daisuke; Nishizawa, Shigeru [University of Occupational and Environmental Health, Department of Neurosurgery, Kitakyusyu (Japan); Kakeda, Shingo; Korogi, Yukunori [University of Occupational and Environmental Health, Department of Radiology, Kitakyusyu (Japan)

    2011-06-15

    The purpose of this study was to evaluate the role of contrast-enhanced fast imaging with steady-state acquisition (CE-FIESTA) for assessing whether dural attachment in intracranial meningiomas is adhesive or not by correlation with intraoperative findings. Fourteen consecutive patients who were candidates for surgical treatment of meningiomas were prospectively analyzed with preoperative magnetic resonance imaging, including CE-FIESTA at 3 T. First, two neuroradiologists assessed several characteristics of the attachment of the meningioma to the dura mater or skull base on CE-FIESTA images. Second, the surgical findings of adhesion at the dural attachment of meningiomas were evaluated by two neurosurgeons. Finally, the CE-FIESTA findings were correlated with the surgical findings by one neurosurgeon and one neuroradiologist by consensus. CE-FIESTA clearly depicted a hypointense marginal line at the attachment site of the meningioma. When CE-FIESTA revealed smooth marginal lines or hyperintense zones along the marginal lines, tumors were detached easily from the dura mater. On the contrary, when CE-FIESTA showed an irregularity, such as partial disruption of the marginal lines, vessels, or bony hyperostosis, the tumors tended to adhere firmly to the dura mater, which was found to contain small vessels and fine fibrous tissues. There seems to be an excellent correlation between the characteristics of dural attachment of meningiomas on CE-FIESTA images and intraoperative findings. Therefore, for operative planning, CE-FIESTA may provide useful information regarding the adhesiveness of dural attachment. (orig.)

  10. Rapid and accurate tumor-target bio-imaging through specific in vivo biosynthesis of a fluorescent europium complex.

    Science.gov (United States)

    Ye, Jing; Wang, Jianling; Li, Qiwei; Dong, Xiawei; Ge, Wei; Chen, Yun; Jiang, Xuerui; Liu, Hongde; Jiang, Hui; Wang, Xuemei

    2016-04-01

    A new and facile method for rapidly and accurately achieving tumor targeting fluorescent images has been explored using a specifically biosynthesized europium (Eu) complex in vivo and in vitro. It demonstrated that a fluorescent Eu complex could be bio-synthesized through a spontaneous molecular process in cancerous cells and tumors, but not prepared in normal cells and tissues. In addition, the proteomics analyses show that some biological pathways of metabolism, especially for NADPH production and glutamine metabolism, are remarkably affected during the relevant biosynthesis process, where molecular precursors of europium ions are reduced to fluorescent europium complexes inside cancerous cells or tumor tissues. These results proved that the specific self-biosynthesis of a fluorescent Eu complex by cancer cells or tumor tissues can provide a new strategy for accurate diagnosis and treatment strategies in the early stages of cancers and thus is beneficial for realizing precise surgical intervention based on the relevant cheap and readily available agents.

  11. Rapid Follow-Up Observations of Tidal Disruption Events Discovered in the GALEX Ultra-Deep Imaging Survey

    Science.gov (United States)

    Gezari, Suvi

    2005-09-01

    Luminous UV/X-ray flares are predicted to occur in the nuclei of inactive galaxies when a star is tidally disrupted by the galaxy's central supermassive black hole (SMBH), and the bound fraction of the tidal debris is accreted. The GALEX Ultra-Deep Imaging Survey (UDIS) has the ideal depth, wavelength coverage, and temporal sampling for detecting flares from TDEs in the nuclei of galaxies over a large range of redshifts. We propose to catch the decay of candidate tidal disruption flares discovered in the UDIS with rapid follow-up TOO Chandra observations, and measure for the first time, the early phase of the decay of a tidal disruption flare in detail in the soft and hard X-rays.

  12. Chaîne de traitement automatisée pour l'acquisition par drone d'images multispectrales haute résolution de parcelles de culture

    OpenAIRE

    Rabatel, G.; Labbé, S.

    2015-01-01

    International audience; In the context of the RHEA European project addressing site-specific weeding on arable crops, a complete aerial image acquisition chain has been developed, providing a geo-referenced multispectral image of a total parcel with 1 cm spatial resolution. Robust automatic ground control point detection and near infrared - visible sensor image registration modules have been implemented and associated with the MicMac photogrammetric software suite to provide a fully automatiz...

  13. Advanced CLARITY for rapid and high-resolution imaging of intact tissues.

    Science.gov (United States)

    Tomer, Raju; Ye, Li; Hsueh, Brian; Deisseroth, Karl

    2014-07-01

    CLARITY is a method for chemical transformation of intact biological tissues into a hydrogel-tissue hybrid, which becomes amenable to interrogation with light and macromolecular labels while retaining fine structure and native biological molecules. This emerging accessibility of information from large intact samples has created both new opportunities and new challenges. Here we describe protocols spanning multiple dimensions of the CLARITY workflow, ranging from simple, reliable and efficient lipid removal without electrophoretic instrumentation (passive CLARITY) to optimized objectives and integration with light-sheet optics (CLARITY-optimized light-sheet microscopy (COLM)) for accelerating data collection from clarified samples by several orders of magnitude while maintaining or increasing quality and resolution. The entire protocol takes from 7-28 d to complete for an adult mouse brain, including hydrogel embedding, full lipid removal, whole-brain antibody staining (which, if needed, accounts for 7-10 of the days), and whole-brain high-resolution imaging; timing within this window depends on the choice of lipid removal options, on the size of the tissue, and on the number and type of immunostaining rounds performed. This protocol has been successfully applied to the study of adult mouse, adult zebrafish and adult human brains, and it may find many other applications in the structural and molecular analysis of large assembled biological systems.

  14. Rapid and non-destructive assessment of polyunsaturated fatty acids contents in Salmon using near-infrared hyperspectral imaging

    Science.gov (United States)

    Tao, Feifei; Mba, Ogan; Liu, Li; Ngadi, Michael

    2017-04-01

    Polyunsaturated fatty acids (PUFAs) are important nutrients present in Salmon. However, current methods for quantifying the fatty acids (FAs) contents in foods are generally based on gas chromatography (GC) technique, which is time-consuming, laborious and destructive to the tested samples. Therefore, the capability of near-infrared (NIR) hyperspectral imaging to predict the PUFAs contents of C20:2 n-6, C20:3 n-6, C20:5 n-3, C22:5 n-3 and C22:6 n-3 in Salmon fillets in a rapid and non-destructive way was investigated in this work. Mean reflectance spectra were first extracted from the region of interests (ROIs), and then the spectral pre-processing methods of 2nd derivative and Savitzky-Golay (SG) smoothing were performed on the original spectra. Based on the original and the pre-processed spectra, PLSR technique was employed to develop the quantitative models for predicting each PUFA content in Salmon fillets. The results showed that for all the studied PUFAs, the quantitative models developed using the pre-processed reflectance spectra by "2nd derivative + SG smoothing" could improve their modeling results. Good prediction results were achieved with RP and RMSEP of 0.91 and 0.75 mg/g dry weight, 0.86 and 1.44 mg/g dry weight, 0.82 and 3.01 mg/g dry weight for C20:3 n-6, C22:5 n-3 and C20:5 n-3, respectively after pre-processing by "2nd derivative + SG smoothing". The work demonstrated that NIR hyperspectral imaging could be a useful tool for rapid and non-destructive determination of the PUFA contents in fish fillets.

  15. Rapid fabrication of carbon quantum dots as multifunctional nanovehicles for dual-modal targeted imaging and chemotherapy.

    Science.gov (United States)

    Chiu, Sheng-Hui; Gedda, Gangaraju; Girma, Wubshet Mekonnen; Chen, Jem-Kun; Ling, Yong-Chien; Ghule, Anil V; Ou, Keng-Liang; Chang, Jia-Yaw

    2016-12-01

    Herein, we synthesized an S, N, and Gd tri-element doped magnetofluorescent carbon quantum dots (GdNS@CQDs) within 10min by using a one-pot microwave method. Our results showed that these magnetofluorescent GdNS@CQDs have excellent fluorescent and magnetic properties. Moreover, GdNS@CQDs exhibited high stability at physiological conditions and ionic strength. These magnetofluorescent GdNS@CQDs were conjugated with a folic acid, denoted as FA-GdNS@CQDs, for targeting dual modal fluorescence/magnetic resonance (MR) imaging. The in vitro and in vivo studies confirmed the high biocompatibility and low toxicity of FA-GdNS@CQDs. FA-GdNS@CQDs enhanced the MR response as compared to that for commercial Gd-DTPA. The targeting capabilities of FA-GdNS@CQDs were confirmed in HeLa and HepG2 cells using in vitro fluorescence and MR dual modality imaging. Additionally, an anticancer drug, doxorubicin, was incorporated into the FA-GdNS@CQDs forming FA-GdNS@CQDs-DOX, which enables targeted drug delivery. Importantly, the prepared FA-GdNS@CQDs-DOX showed a high quantity of doxorubicin loading capacity (about 80%) and pH-sensitive drug release. The uptake into cancer cells and the intracellular location of the FA-GdNS@CQDs were observed by confocal laser scanning microscopy. We also successfully demonstrated in vivo fluorescence bio imaging of the FA-GdNS@CQDs, using zebrafish as an animal model. In this manuscript, we reported a facial, rapid, and environmental friendly method to fabricate hetero atoms including gadolinium, nitrogen, and sulfur doped multi-functional magnetofluorescent carbon quantum dots (GdNS@CQDs) nanocomposite. These multifunctional GdNS@CQDs were conjugated with a folic acid for targeting dual modal fluorescence/magnetic resonance imaging. Additionally, an anticancer drug, doxorubicin, was incorporated into the nanocomposite forming FA-GdNS@CQDs-DOX, which enables targeted drug delivery. We have developed GdNS@CQDs with integrated functions for simultaneous in

  16. Mergers & Acquisitions

    DEFF Research Database (Denmark)

    Fomcenco, Alex

    MERGERS & ACQUISITIONS: Counseling and Choice of Method describes and analyzes the current state of law in Europe in regard to some relevant selected elements related to mergers and acquisitions, and the adviser’s counsel in this regard. The focus is aimed and maintained at application...

  17. Rapid prototyping of SoC-based real-time vision system: application to image preprocessing and face detection

    Science.gov (United States)

    Jridi, Maher; Alfalou, Ayman

    2017-05-01

    By this paper, the major goal is to investigate the Multi-CPU/FPGA SoC (System on Chip) design flow and to transfer a know-how and skills to rapidly design embedded real-time vision system. Our aim is to show how the use of these devices can be benefit for system level integration since they make possible simultaneous hardware and software development. We take the facial detection and pretreatments as case study since they have a great potential to be used in several applications such as video surveillance, building access control and criminal identification. The designed system use the Xilinx Zedboard platform. The last is the central element of the developed vision system. The video acquisition is performed using either standard webcam connected to the Zedboard via USB interface or several camera IP devices. The visualization of video content and intermediate results are possible with HDMI interface connected to HD display. The treatments embedded in the system are as follow: (i) pre-processing such as edge detection implemented in the ARM and in the reconfigurable logic, (ii) software implementation of motion detection and face detection using either ViolaJones or LBP (Local Binary Pattern), and (iii) application layer to select processing application and to display results in a web page. One uniquely interesting feature of the proposed system is that two functions have been developed to transmit data from and to the VDMA port. With the proposed optimization, the hardware implementation of the Sobel filter takes 27 ms and 76 ms for 640x480, and 720p resolutions, respectively. Hence, with the FPGA implementation, an acceleration of 5 times is obtained which allow the processing of 37 fps and 13 fps for 640x480, and 720p resolutions, respectively.

  18. Fast abdominal magnetic resonance imaging; Schnelle Abdomenbildgebung in der Magnetresonanztomografie

    Energy Technology Data Exchange (ETDEWEB)

    Budjan, J.; Schoenberg, S.O.; Riffel, P. [University Medical Center Mannheim (Germany). Dept. of Clinical Radiology and Nuclear Medicine

    2016-06-15

    Abdominal imaging is the driving force that necessitates the development of numerous techniques for accelerated image acquisition in magnetic resonance imaging (MRI). Today, numerous techniques are available that enable rapid, high spatial resolution acquisition for both T1 and T2 weighted images. These techniques open new opportunities in the detection and classification of numerous pathologies in the abdomen. However, there is still ongoing progress in the development of fast and ultrafast sequences and promising techniques are currently close to clinical application. With these 4D-technologies, MRI is becoming the central imaging modality for dynamic, motion-compensated imaging of the parenchymal abdominal organs such as liver, pancreas and kidney.

  19. Rapid sphere sizing using a Bayesian analysis of reciprocal space imaging data.

    Science.gov (United States)

    Ziovas, K; Sederman, A J; Gehin-Delval, C; Gunes, D Z; Hughes, E; Mantle, M D

    2016-01-15

    Dispersed systems are important in many applications in a wide range of industries such as the petroleum, pharmaceutical and food industries. Therefore the ability to control and non-invasively measure the physical properties of these systems, such as the dispersed phase size distribution, is of significant interest, in particular for concentrated systems, where microscopy or scattering techniques may not apply or with very limited output quality. In this paper we show how reciprocal space data acquired using both 1D magnetic resonance imaging (MRI) and 2D X-ray micro-tomographic (X-ray μCT) data can be analysed, using a Bayesian statistical model, to extract the sphere size distribution (SSD) from model sphere systems and dispersed food foam samples. Glass spheres-in-xanthan gels were used as model samples with sphere diameters (D) in the range of 45μm⩽D⩽850μm. The results show that the SSD was successfully estimated from both the NMR and X-ray μCT with a good degree of accuracy for the entire range of glass spheres in times as short as two seconds. After validating the technique using model samples, the Bayesian sphere sizing method was successfully applied to air/water foam samples generated using a microfluidics apparatus with 160μm⩽D⩽400μm. The effect of different experimental parameters such as the standard deviation of the bubble size distribution and the volume fraction of the dispersed phase is discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Towards the automated localisation of targets in rapid image-sifting by collaborative brain-computer interfaces.

    Directory of Open Access Journals (Sweden)

    Ana Matran-Fernandez

    Full Text Available The N2pc is a lateralised Event-Related Potential (ERP that signals a shift of attention towards the location of a potential object of interest. We propose a single-trial target-localisation collaborative Brain-Computer Interface (cBCI that exploits this ERP to automatically approximate the horizontal position of targets in aerial images. Images were presented by means of the rapid serial visual presentation technique at rates of 5, 6 and 10 Hz. We created three different cBCIs and tested a participant selection method in which groups are formed according to the similarity of participants' performance. The N2pc that is elicited in our experiments contains information about the position of the target along the horizontal axis. Moreover, combining information from multiple participants provides absolute median improvements in the area under the receiver operating characteristic curve of up to 21% (for groups of size 3 with respect to single-user BCIs. These improvements are bigger when groups are formed by participants with similar individual performance, and much of this effect can be explained using simple theoretical models. Our results suggest that BCIs for automated triaging can be improved by integrating two classification systems: one devoted to target detection and another to detect the attentional shifts associated with lateral targets.

  1. Rapid detection of Clostridium difficile via magnetic bead aggregation in cost-effective polyester microdevices with cell phone image analysis.

    Science.gov (United States)

    DuVall, Jacquelyn A; Cabaniss, Scott T; Angotti, Morgan L; Moore, John H; Abhyankar, Mayuresh; Shukla, Nishant; Mills, Daniel L; Kessel, Bryan G; Garner, Gavin T; Swami, Nathan S; Landers, James P

    2016-10-07

    Pathogen detection has traditionally been accomplished by utilizing methods such as cell culture, immunoassays, and nucleic acid amplification tests; however, these methods are not easily implemented in resource-limited settings because special equipment for detection and thermal cycling is often required. In this study, we present a magnetic bead aggregation assay coupled to an inexpensive microfluidic fabrication technique that allows for cell phone detection and analysis of a notable pathogen in less than one hour. Detection is achieved through the use of a custom-built system that allows for fluid flow control via centrifugal force, as well as manipulation of magnetic beads with an adjustable rotating magnetic field. Cell phone image capture and analysis is housed in a 3D-printed case with LED backlighting and a lid-mounted Android phone. A custom-written application (app.) is employed to interrogate images for the extent of aggregation present following loop-mediated isothermal amplification (LAMP) coupled to product-inhibited bead aggregation (PiBA) for detection of target sequences. Clostridium difficile is a pathogen of increasing interest due to its causative role in intestinal infections following antibiotic treatment, and was therefore chosen as the pathogen of interest in the present study to demonstrate the rapid, cost-effective, and sequence-specific detection capabilities of the microfluidic platform described herein.

  2. Characterization of Diesel and Gasoline Compression Ignition Combustion in a Rapid Compression-Expansion Machine using OH* Chemiluminescence Imaging

    Science.gov (United States)

    Krishnan, Sundar Rajan; Srinivasan, Kalyan Kumar; Stegmeir, Matthew

    2015-11-01

    Direct-injection compression ignition combustion of diesel and gasoline were studied in a rapid compression-expansion machine (RCEM) using high-speed OH* chemiluminescence imaging. The RCEM (bore = 84 mm, stroke = 110-250 mm) was used to simulate engine-like operating conditions at the start of fuel injection. The fuels were supplied by a high-pressure fuel cart with an air-over-fuel pressure amplification system capable of providing fuel injection pressures up to 2000 bar. A production diesel fuel injector was modified to provide a single fuel spray for both diesel and gasoline operation. Time-resolved combustion pressure in the RCEM was measured using a Kistler piezoelectric pressure transducer mounted on the cylinder head and the instantaneous piston displacement was measured using an inductive linear displacement sensor (0.05 mm resolution). Time-resolved, line-of-sight OH* chemiluminescence images were obtained using a Phantom V611 CMOS camera (20.9 kHz @ 512 x 512 pixel resolution, ~ 48 μs time resolution) coupled with a short wave pass filter (cut-off ~ 348 nm). The instantaneous OH* distributions, which indicate high temperature flame regions within the combustion chamber, were used to discern the characteristic differences between diesel and gasoline compression ignition combustion. The authors gratefully acknowledge facilities support for the present work from the Energy Institute at Mississippi State University.

  3. Automated short-axis cardiac magnetic resonance image acquisitions: accuracy of left ventricular dimension measurements in normal subjects and patients.

    Science.gov (United States)

    Danilouchkine, Mikhail G; Westenberg, Jos J M; Reiber, Johan H C; Lelieveldt, Boudewijn P F

    2004-12-01

    This study investigates the use of an automated observer-independent planning system for short-axis cardiovascular magnetic resonance (MR) acquisitions in the clinical environment. The capacity of the automated method to produce accurate measurements of left ventricular dimensions and function was quantitatively assessed in normal subjects and patients. Fourteen healthy volunteers and 8 patients underwent cardiovascular MR (CMR) acquisitions for ventricular function assessment. Short-axis datasets of the left ventricle (LV) were acquired in 2 ways: manually planned and generated in an automatic fashion. End-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), and left ventricular mass (LVM) were derived from the 2 datasets. The agreement between the manual and automatic planning methods was assessed. The mean differences between the manual and automated CMR planning methods for the normal subjects and patients were 5.89 mL and 1.93 mL (EDV), 1.14 mL and -0.41 mL (ESV), 0.81% and 0.89% (EF), and 4.35 g and 3.88 g (LVM), respectively. There was no significant difference in ESV and EF. LVM significantly differed in both groups, whereas EDV was significantly different in the normal subjects and insignificantly different in the patients. The variability coefficients were 2.8 and 3.59 (EDV), 3.3 and 5.03 (ESV), 1.79 and 2.65 (EF), and 4.36 and 2.27 (LVM) for the normal subjects and patients, respectively. The mean angular deviation of the LV axes turned out to be 8.58 +/- 5.76 degrees for the normal subjects and 8.35 +/- 5.15 degrees for the patients. Automated CMR planning method can provide accurate measurements of LV dimensions in normal subjects and patients, and therefore, can be used in the clinical environment for functional assessment of the human cardiovascular system.

  4. An open-source, FireWire camera-based, Labview-controlled image acquisition system for automated, dynamic pupillometry and blink detection.

    Science.gov (United States)

    de Souza, John Kennedy Schettino; Pinto, Marcos Antonio da Silva; Vieira, Pedro Gabrielle; Baron, Jerome; Tierra-Criollo, Carlos Julio

    2013-12-01

    The dynamic, accurate measurement of pupil size is extremely valuable for studying a large number of neuronal functions and dysfunctions. Despite tremendous and well-documented progress in image processing techniques for estimating pupil parameters, comparatively little work has been reported on practical hardware issues involved in designing image acquisition systems for pupil analysis. Here, we describe and validate the basic features of such a system which is based on a relatively compact, off-the-shelf, low-cost FireWire digital camera. We successfully implemented two configurable modes of video record: a continuous mode and an event-triggered mode. The interoperability of the whole system is guaranteed by a set of modular software components hosted on a personal computer and written in Labview. An offline analysis suite of image processing algorithms for automatically estimating pupillary and eyelid parameters were assessed using data obtained in human subjects. Our benchmark results show that such measurements can be done in a temporally precise way at a sampling frequency of up to 120 Hz and with an estimated maximum spatial resolution of 0.03 mm. Our software is made available free of charge to the scientific community, allowing end users to either use the software as is or modify it to suit their own needs. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  5. MERGERS & ACQUISITIONS

    National Research Council Canada - National Science Library

    Rodgers Mavhiki

    2013-01-01

      Mergers and acquisitions (M&A) tend to be dominated by M&A specialists such as lawyers, valuations specialists and investment gurus, leaving the funding function for the Chief Financial Officer (CFO...

  6. Aquisição e manipulação de imagens por tomografia computadorizada da região maxilofacial visando à obtenção de protótipos biomédicos Acquisition and manipulation of computed tomography images of the maxillofacial region for biomedical prototyping

    Directory of Open Access Journals (Sweden)

    Maria Inês Meurer

    2008-02-01

    Full Text Available O processo de construção de protótipos biomédicos surgiu da união das tecnologias de prototipagem rápida e do diagnóstico por imagens. No entanto, este processo é complexo, em função da necessária interação entre as ciências biomédicas e a engenharia. Para que bons resultados sejam obtidos, especial atenção deve ser dispensada à aquisição das imagens por tomografia computadorizada e à manipulação dessas imagens em softwares específicos. Este artigo apresenta a experiência multidisciplinar de um grupo de pesquisadores com a aquisição e a manipulação de imagens por tomografia computadorizada do complexo maxilofacial, visando à construção de protótipos biomédicos com finalidade cirúrgica.Biomedical prototyping has resulted from a merger of rapid prototyping and imaging diagnosis technologies. However, this process is complex, considering the necessity of interaction between biomedical sciences and engineering. Good results are highly dependent on the acquisition of computed tomography images and their subsequent manipulation by means of specific softwares. The present study describes the experience of a multidisciplinary group of researchers in the acquisition and manipulation of computed tomography images of the maxillofacial region aiming at biomedical prototyping for surgical purposes.

  7. Preliminary timing measurements on a data acquisition chain for a SiPM-based detector for prostate imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gabrielli, A.; Antonioli, P.; D' Antone, I.; Giorgi, F.M.; Lax, I.; Lolli, M. [Physics Department University of Bologna Viale Berti Pichat 6/2, 40127, Bologna (Italy); De Leo, R.; De Robertis, G.; Foresta, M.; Loddo, F.; Ranieri, A. [INFN University of Bari (Italy); Cosentino, G.; Finocchiaro, P.; Pappalardo, A.D. [INFN LNS University of Catania (Italy); Fonte, R. [INFN Catania (Italy); Calvini, C.; Musico, P.; Ottonello, P. [INFN Genova (Italy); Cusanno, F.; Garibaldi, F. [INFN Roma1 and gruppo collegato ISS (Italy)

    2011-06-15

    Prostate cancer (PC) is one of the most common diseases in western countries and a leading cause of cancer death. A variety of treatment options are available but a precise disease characterization is needed: evaluation of cancer location, size, and extent and an indication of tumor aggressiveness. The current standard for diagnosing PC is transrectal ultrasound guided sextant biopsy. A novel multidisciplinary approach is required. Imaging may play a key role provided that dedicated prostate imagers and procedures are available: considerable improvements have been achieved in diagnosis with the Magnetic Resonance Imaging (MRI) and nuclear medicine (Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT)) techniques. Nevertheless, due to sub-optimal prostate imaging geometries with these generic large instruments preventing separation of the signal from surrounding organs, the sensitivity, spatial resolution and lesion contrast detected are lower compared to what can be potentially achievable with optimized dedicated prostate imagers and procedures. Fully exploiting the Time Of Flight (TOF) capability would allow not only to increase the Signal-to-Noise ratio (SNR) / Noise Equivalent Count Rate (NECR) but also to get rid of the huge background coming from neighboring organs i.e. the bladder. Recently a new research project was initiated by a large INFN collaboration, and a 'TOF-PET and MRI for prostate cancer diagnosis and follow up experiment' (TOPEM) was financed as a 3-year experiment by the Italian 'INFN Commissione Scientifica Nazionale V' with the goal of designing, building and testing in phantom tests an endorectal PET-TOF probe compatible with MRI.

  8. Plasmonic Thermal Decomposition/Digestion of Proteins: A Rapid On-Surface Protein Digestion Technique for Mass Spectrometry Imaging.

    Science.gov (United States)

    Zhou, Rong; Basile, Franco

    2017-09-05

    A method based on plasmon surface resonance absorption and heating was developed to perform a rapid on-surface protein thermal decomposition and digestion suitable for imaging mass spectrometry (MS) and/or profiling. This photothermal process or plasmonic thermal decomposition/digestion (plasmonic-TDD) method incorporates a continuous wave (CW) laser excitation and gold nanoparticles (Au-NPs) to induce known thermal decomposition reactions that cleave peptides and proteins specifically at the C-terminus of aspartic acid and at the N-terminus of cysteine. These thermal decomposition reactions are induced by heating a solid protein sample to temperatures between 200 and 270 °C for a short period of time (10-50 s per 200 μm segment) and are reagentless and solventless, and thus are devoid of sample product delocalization. In the plasmonic-TDD setup the sample is coated with Au-NPs and irradiated with 532 nm laser radiation to induce thermoplasmonic heating and bring about site-specific thermal decomposition on solid peptide/protein samples. In this manner the Au-NPs act as nanoheaters that result in a highly localized thermal decomposition and digestion of the protein sample that is independent of the absorption properties of the protein, making the method universally applicable to all types of proteinaceous samples (e.g., tissues or protein arrays). Several experimental variables were optimized to maximize product yield, and they include heating time, laser intensity, size of Au-NPs, and surface coverage of Au-NPs. Using optimized parameters, proof-of-principle experiments confirmed the ability of the plasmonic-TDD method to induce both C-cleavage and D-cleavage on several peptide standards and the protein lysozyme by detecting their thermal decomposition products with matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The high spatial specificity of the plasmonic-TDD method was demonstrated by using a mask to digest designated sections of

  9. Acquisition of a Surface Plasmon Resonance Imager, Digital Microscope, and Peristaltic Pumps for Defense-Based Research

    Science.gov (United States)

    2016-05-05

    small power sources to operate them. We have been developing microfluidic formate, methanol , and hydrogen fuel cells (FCs). The use of these... fuels entails one of the most promising mobile technologies by which such power can be provided. FCs can be considered chemical reactors designed to...SECURITY CLASSIFICATION OF: The goal of this proposal is to purchase the GWC Technologies , Inc. Horizontal Surface Plasmon Resonance Imaging (SPRi

  10. Acquisition and interpretation of focused diagnostic ultrasound images by ultrasound-naive advanced paramedics: trialling a PHUS education programme.

    Science.gov (United States)

    Brooke, Mike; Walton, Julie; Scutt, Diane; Connolly, Jim; Jarman, Bob

    2012-04-01

    This trial investigated whether advanced paramedics from a UK regional ambulance service have the ability to acquire and interpret diagnostic quality ultrasound images following a 2-day programme of education and training covering the fundamental aspects of lung ultrasound. The participants were tested using a two-part examination; assessing both their theoretical understanding of image interpretation and their practical ability to acquire diagnostic quality ultrasound images. The results obtained were subsequently compared with those obtained from expert physician sonographers. The advanced paramedics demonstrated an overall accuracy in identifying the presence or absence of pneumothorax in M-mode clips of 0.94 (CI 0.86 to 0.99), compared with the experts who achieved 0.93 (CI 0.67 to 1.0). In two-dimensional mode, the advanced paramedics demonstrated an overall accuracy of 0.78 (CI 0.72 to 0.83), compared with the experts who achieved 0.76 (CI 0.62 to 0.86). In total, the advanced paramedics demonstrated an overall accuracy at identifying the presence or absence of pneumothorax in prerecorded video clip images of 0.82 (CI 0.77 to 0.86), in comparison with the expert users of 0.80 (CI 0.68 to 0.88). All of the advanced paramedics passed the objective structured clinical examination and achieved a practical standard considered by the examiners to be equivalent to that which would be expected from candidates enrolled on the thoracic module of the College of Emergency Medicine level 2 ultrasound programme. This trial demonstrated that ultrasound-naive practitioners can achieve an acceptable standard of competency in a simulated environment in a relatively short period of time.

  11. An Evaluation of the Benefits of Simultaneous Acquisition on PET/MR Coregistration in Head/Neck Imaging

    Science.gov (United States)

    Monti, Serena; Cavaliere, Carlo; Covello, Mario; Nicolai, Emanuele; Salvatore, Marco; Aiello, Marco

    2017-01-01

    Coregistration of multimodal diagnostic images is crucial for qualitative and quantitative multiparametric analysis. While retrospective coregistration is computationally intense and could be inaccurate, hybrid PET/MR scanners allow acquiring implicitly coregistered images. Aim of this study is to assess the performance of state-of-the-art coregistration methods applied to PET and MR acquired as single modalities, comparing the results with the implicitly coregistration of a hybrid PET/MR, in complex anatomical regions such as head/neck (HN). A dataset consisting of PET/CT and PET/MR subsequently acquired in twenty-three patients was considered: performance of rigid (RR) and deformable (DR) registration obtained by a commercial software and an open-source registration package was evaluated. Registration accuracy was qualitatively assessed in terms of visual alignment of anatomical structures and qualitatively measured by the Dice scores computed on segmented tumors in PET and MRI. The resulting scores highlighted that hybrid PET/MR showed higher registration accuracy than retrospectively coregistered images, because of an overall misalignment after RR, unrealistic deformations and volume variations after DR. DR revealed superior performance compared to RR due to complex nonrigid movements of HN district. Moreover, simultaneous PET/MR offers unique datasets serving as ground truth for the improvement and validation of coregistration algorithms, if acquired with PET/CT. © 2017 Serena Monti et al.

  12. A database of 629 English compound words: ratings of familiarity, lexeme meaning dominance, semantic transparency, age of acquisition, imageability, and sensory experience.

    Science.gov (United States)

    Juhasz, Barbara J; Lai, Yun-Hsuan; Woodcock, Michelle L

    2015-12-01

    Since the work of Taft and Forster (1976), a growing literature has examined how English compound words are recognized and organized in the mental lexicon. Much of this research has focused on whether compound words are decomposed during recognition by manipulating the word frequencies of their lexemes. However, many variables may impact morphological processing, including relational semantic variables such as semantic transparency, as well as additional form-related and semantic variables. In the present study, ratings were collected on 629 English compound words for six variables [familiarity, age of acquisition (AoA), semantic transparency, lexeme meaning dominance (LMD), imageability, and sensory experience ratings (SER)]. All of the compound words selected for this study are contained within the English Lexicon Project (Balota et al., 2007), which made it possible to use a regression approach to examine the predictive power of these variables for lexical decision and word naming performance. Analyses indicated that familiarity, AoA, imageability, and SER were all significant predictors of both lexical decision and word naming performance when they were added separately to a model containing the length and frequency of the compounds, as well as the lexeme frequencies. In addition, rated semantic transparency also predicted lexical decision performance. The database of English compound words should be beneficial to word recognition researchers who are interested in selecting items for experiments on compound words, and it will also allow researchers to conduct further analyses using the available data combined with word recognition times included in the English Lexicon Project.

  13. Imaging characterization of the rapid adiabatic passage in a source-rotatable, crossed-beam scattering experiment

    Science.gov (United States)

    Pan, Huilin; Mondal, Sohidul; Yang, Chung-Hsin; Liu, Kopin

    2017-07-01

    In order to achieve a more efficient preparation of a specific ro-vibrationally excited reactant state for reactive scattering experiments, we implemented the rapid adiabatic passage (RAP) scheme to our pulsed crossed-beam machine, using a single-mode, continuous-wave mid-infrared laser. The challenge for this source-rotatable apparatus lies in the non-orthogonal geometry between the molecular beam and the laser propagation directions. As such, the velocity spread of the supersonic beam results in a significantly broader Doppler distribution that needs to be activated for RAP to occur than the conventional orthogonal configuration. In this report, we detail our approach to shifting, locking, and stabilizing the absolute mid-infrared frequency. We exploited the imaging detection technique to characterize the RAP process and to quantify the excitation efficiency. We showed that with appropriate focusing of the IR laser, a nearly complete population transfer can still be achieved in favorable cases. Compared to our previous setup—a pulsed optical parametric oscillator/amplifier in combination with a multipass ring reflector for saturated absorption, the present RAP scheme with a single-pass, continuous-wave laser yields noticeably higher population-transfer efficiency.

  14. Reduced medial prefrontal-subcortical connectivity in dysphoria: Granger causality analyses of rapid functional magnetic resonance imaging.

    Science.gov (United States)

    Sabatinelli, Dean; McTeague, Lisa M; Dhamala, Mukesh; Frank, David W; Wanger, Timothy J; Adhikari, Bhim M

    2015-02-01

    A cortico-limbic network consisting of the amygdala, medial prefrontal cortex (mPFC), and ventral striatum (vSTR) has been associated with altered function in emotional disorders. Here we used rapidly sampled functional magnetic resonance imaging and Granger causality analyses to assess the directional connectivity between these brain structures in a sample of healthy and age-matched participants endorsing moderate to severe depressive symptomatology as they viewed a series of natural scene stimuli varying systematically in pleasantness and arousal. Specifically during pleasant scene perception, dysphoric participants showed reduced activity in mPFC and vSTR, relative to healthy participants. In contrast, amygdala activity was enhanced to pleasant as well as unpleasant arousing scenes in both participant groups. Granger causality estimates of influence between mPFC and vSTR were significantly reduced in dysphoric relative to control participants during all picture contents. These findings provide direct evidence that during visual perception of evocative emotional stimuli, reduced reward-related activity in dysphoria is associated with dysfunctional causal connectivity between mPFC, amygdala, and vSTR.

  15. Technique for diamond machining large ZnSe grisms for the Rapid Infrared/Imager Spectrograph (RIMAS)

    Science.gov (United States)

    Kuzmenko, Paul J.; Little, Steve L.; Kutyrev, Alexander S.; Capone, John I.

    2016-07-01

    The Rapid Infrared Imager/Spectrograph (RIMAS) is an instrument designed to observe gamma ray burst afterglows following initial detection by the SWIFT satellite. Operating in the near infrared between 0.9 and 2.4 μm, it has capabilities for both low resolution (R 25) and moderate resolution (R 4000) spectroscopy. Two zinc selenide (ZnSe) grisms provide dispersion in the moderate resolution mode: one covers the Y and J bands and the other covers the H and K. Each has a clear aperture of 44 mm. The YJ grism has a blaze angle of 49.9° with a 40 μm groove spacing. The HK grism is blazed at 43.1° with a 50 μm grooves spacing. Previous fabrication of ZnSe grisms on the Precision Engineering Research Lathe (PERL II) at LLNL has demonstrated the importance of surface preparation, tool and fixture design, tight thermal control, and backup power sources for the machine. The biggest challenges in machining the RIMAS grisms are the large grooved area, which indicates long machining time, and the relatively steep blaze angle, which means that the grism wavefront error is much more sensitive to lathe metrology errors. Mitigating techniques are described.

  16. Quasi-simultaneous acquisition of hard electron ionization and soft single-photon ionization mass spectra during GC/MS analysis by rapid switching between both ionization methods: analytical concept, setup, and application on diesel fuel.

    Science.gov (United States)

    Eschner, Markus S; Gröger, Thomas M; Horvath, Thomas; Gonin, Marc; Zimmermann, Ralf

    2011-05-15

    This work describes the realization of rapid switching between hard electron ionization (EI) and soft single-photon ionization (SPI) integrated in a compact orthogonal acceleration time-of-flight mass spectrometer. Vacuum-ultraviolet (VUV) photons of 9.8 eV (126 nm) emitted from the innovative electron-beam-pumped rare-gas excimer light source (EBEL) filled with argon are focused into the ion chamber by an ellipsoidal mirror optic for accomplishing of SPI. This novel orthogonal acceleration time-of-flight mass spectrometer with switching capability was hyphenated to one-dimensional gas chromatography (GC) and comprehensive two-dimensional (2D) gas chromatography (GC × GC) for the first time. Within this demonstration study, a maximum switching frequency of 80 Hz was applied for investigation of a mineral-oil-type diesel sample. This approach allows the quasi-simultaneous acquisition of complementary information about the fragmentation pattern (EI) as well as the molecular mass (SPI) of compounds within a single analysis. Furthermore, by application of a polar GC column for separation, the SPI data can be displayed in a 2D contour plot, leading to a comprehensive 2D characterization (GC × MS), whereas the typical group-type assignment for diesel is also met.

  17. Mergers and acquisitions for the radiologist.

    Science.gov (United States)

    Fleishon, Howard B

    2008-05-01

    In 2006 and the first half of 2007, the rapid pace of global activity contributed to the popularity of mergers and acquisitions (M&A). In fact, the medical imaging industry has a significant history in M&A as well. Along with the expectation of continued growth in medical imaging utilization and other industry trends, radiologists may become more involved in M&A transactions. There is little in the radiology literature dealing with the logistics and pitfalls of M&A. This article is an introduction for radiologists who might consider buying or selling their practices or merging with strategic partners. Although there are significant differences in the approaches of buy or sell situations compared with mergers, they do share several concepts that are outlined. One key to success in M&A transactions is the "process" or approach, which is described with some practical guidelines. Some basic terms and suggestions are also presented for reference.

  18. Affective Norms for 4900 Polish Words Reload (ANPW_R): Assessments for Valence, Arousal, Dominance, Origin, Significance, Concreteness, Imageability and, Age of Acquisition.

    Science.gov (United States)

    Imbir, Kamil K

    2016-01-01

    In studies that combine understanding of emotions and language, there is growing demand for good-quality experimental materials. To meet this expectation, a large number of 4905 Polish words was assessed by 400 participants in order to provide a well-established research method for everyone interested in emotional word processing. The Affective Norms for Polish Words Reloaded (ANPW_R) is designed as an extension to the previously introduced the ANPW dataset and provides assessments for eight different affective and psycholinguistic measures of Valence, Arousal, Dominance, Origin, Significance, Concreteness, Imageability, and subjective Age of Acquisition. The ANPW_R is now the largest available dataset of affective words for Polish, including affective scores that have not been measured in any other dataset (concreteness and age of acquisition scales). Additionally, the ANPW_R allows for testing hypotheses concerning dual-mind models of emotion and activation (origin and subjective significance scales). Participants in the current study assessed all 4905 words in the list within 1 week, at their own pace in home sessions, using eight different Self-assessment Manikin (SAM) scales. Each measured dimension was evaluated by 25 women and 25 men. The ANPW_R norms appeared to be reliable in split-half estimation and congruent with previous normative studies in Polish. The quadratic relation between valence and arousal was found to be in line with previous findings. In addition, nine other relations appeared to be better described by quadratic instead of linear function. The ANPW_R provides well-established research materials for use in psycholinguistic and affective studies in Polish-speaking samples.

  19. Reducing the Effects of Background Noise during Auditory Functional Magnetic Resonance Imaging of Speech Processing: Qualitative and Quantitative Comparisons between Two Image Acquisition Schemes and Noise Cancellation

    Science.gov (United States)

    Blackman, Graham A.; Hall, Deborah A.

    2011-01-01

    Purpose: The intense sound generated during functional magnetic resonance imaging (fMRI) complicates studies of speech and hearing. This experiment evaluated the benefits of using active noise cancellation (ANC), which attenuates the level of the scanner sound at the participant's ear by up to 35 dB around the peak at 600 Hz. Method: Speech and…

  20. Digital still images from Coral Reef Assessment and Monitoring Program (CRAMP) Rapid Assessment Transect surveys from 2006 in the coastal waters of Hawaii, 22 June - 12 December 2006 (NODC Accession 0039627)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of digital still images taken during CRAMP Rapid Assessment Transect surveys taken in 2006 and includes images of substrate type and species....

  1. Assessment of Accelerated Acquisition of Defense Programs

    Science.gov (United States)

    2016-09-01

    117A Stealth Attack Aircraft Crash /rapid/time constrained/spiral Mine-Resistant/Ambush-Protected Vehicle (MRAP) Rapid/time constrained Stryker...contractor. The Air Force delivered the aircraft directly from the factory to the front lines with no developmental or operational testing . Prior...availability: 1. Time-constrained acquisition 2. “ Crash ” program 3. Rapid acquisition 4. Early fielding experiments 5. Spiral/evolutionary

  2. Outcome of universal newborn eye screening with wide-field digital retinal image acquisition system: a pilot study.

    Science.gov (United States)

    Goyal, P; Padhi, T R; Das, T; Pradhan, L; Sutar, S; Butola, S; Behera, U C; Jain, L; Jalali, S

    2017-07-24

    PurposeTo evaluate the outcome of universal newborn eye screening with wide-field digital retinal imaging (WFDRI) system.MethodsIn this pilot study, we examined 1152 apparently healthy newborn infants in the obstetrics and gynecology ward of a civil hospital in Eastern India over 1.5 years. The examination included external eye examination, red reflex test and fundus imaging by WFDRI (RetCam II, Clarity medical system, Pleasanton, CA, USA) by a trained optometrist. The pathologies detected, net monetary gain and skilled manpower saved were documented. The results were compared with three similar studies thus far published in the literature.ResultsOcular abnormality of any kind was seen in 172 (14.93%) babies. Retinal hemorrhage in 153 babies (88.9% of all abnormal findings) was the most common abnormality; it was bilateral in 118 (77.12%) babies and 4 babies had foveal hemorrhage. Other abnormalities included vitreous hemorrhage (n=1), congenital glaucoma (n=2), uveal coloboma (n=2), retinopathy mimicking retinopathy of prematurity (n=2), and cystic fovea (n=3). The retinal hemorrhages resolved spontaneously in all eyes. One baby with congenital glaucoma received surgery and the other was treated medically. The benefits included savings in skilled manpower, a net monetary gain of INR 4.195 million (US$ 62,612) and skilled manpower saving by 319.4 h.ConclusionsThe universal neonatal eye screening using WFDRI detected pathologies that needed immediate care or regular follow up; saved skilled manpower with a net monetary gain. But compared to a red reflex test the benefits were marginal in terms of detecting treatment warranting ocular pathologies.Eye advance online publication, 24 July 2017; doi:10.1038/eye.2017.129.

  3. Tailoring Systems Engineering for Rapid Acquisition

    Science.gov (United States)

    2014-03-27

    constraints associated with the research program, the total number interviews conducted was capped at twelve to allow proper time to conduct data analysis...incremental process or a single time solution? Incremental solutions with interviewee’s organization working the systems from cradle to grave. They are

  4. An Analysis of Army Rapid Acquisition

    Science.gov (United States)

    2015-09-01

    IOT &E initial operational test & evaluation IT information technology IPT integrated process team IUID item unique identification IWN immediate...Forces’ efforts to defeat Improvised Explosive Devices as weapons of strategic influence.”36 JIDA focuses on defeating IEDs, attacking the network , and...deference to private industry to a frame-of-mind more appropriate for a government customer accountable to the U.S. taxpayer. The challenge here is

  5. Rapid detection of Colorado potato beetle damage using small unmanned aircraft

    Science.gov (United States)

    Remote sensing with small unmanned aircraft systems (sUAS) has potential applications in agriculture because low flight altitudes allow image acquisition at very high spatial resolution. Damage to potato fields by the Colorado potato beetle (Leptinotarsa decemlineata) rapidly increases from initial...

  6. The potential for early and rapid pathogen detection within poultry processing through hyperspectral microscopy

    Science.gov (United States)

    The acquisition of hyperspectral microscopic images containing both spatial and spectral data has shown potential for the early and rapid optical classification of foodborne pathogens. A hyperspectral microscope with a metal halide light source and acousto-optical tunable filter (AOTF) collects 89 ...

  7. Rapid microwave-assisted synthesis of PVP-coated ultrasmall gadolinium oxide nanoparticles for magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Vahdatkhah, Parisa [Department of Materials Science and Engineering, Sharif University of Technology (Iran, Islamic Republic of); Madaah Hosseini, Hamid Reza, E-mail: Madaah@sharif.ir [Department of Materials Science and Engineering, Sharif University of Technology (Iran, Islamic Republic of); Khodaei, Azin [Department of Materials Science and Engineering, Sharif University of Technology (Iran, Islamic Republic of); Montazerabadi, Ali Reza [Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences (Iran, Islamic Republic of); Irajirad, Rasoul [Biomolecular Image Analysis Group, Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences (Iran, Islamic Republic of); Oghabian, Mohamad Ali [Biomolecular Image Analysis Group, Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences (Iran, Islamic Republic of); Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences (Iran, Islamic Republic of); Delavari, Hamid H., E-mail: Hamid.delavari@modares.ac.ir [Department of Materials Engineering, Tarbiat Modares University, Tehran, PO Box 14115-143 (Iran, Islamic Republic of)

    2015-05-12

    Highlights: • A rapid microwave-assisted polyol process used to synthesize Gd{sub 2}O{sub 3} nanoparticles. • In situ surface modification of ultrasmall Gd{sub 2}O{sub 3}NPs with PVP has been performed. • Gd{sub 2}O{sub 3}NPs shows considerable increasing of relaxivity in comparison to Gd-chelates. • PVP-covered Gd{sub 2}O{sub 3}NPs show appropriate stability for approximately 15 days. • Spectrophotometric indicates the leaching of free Gd ions not occurred versus time. - Abstract: Synthesis of polyvinyl pyrrolidone (PVP) coated ultrasmall Gd{sub 2}O{sub 3} nanoparticles (NPs) with enhanced T{sub 1}-weighted signal intensity and r{sub 2}/r{sub 1} ratio close to unity is performed by a microwave-assisted polyol process. PVP coated Gd{sub 2}O{sub 3}NPs with spherical shape and uniform size of 2.5 ± 0.5 nm have been synthesized below 5 min and structure and morphology confirmed by HRTEM, XRD and FTIR. The longitudinal (r{sub 1}) and transversal relaxation (r{sub 2}) of Gd{sub 2}O{sub 3}NPs is measured by a 3 T MRI scanner. The results showed considerable increasing of relaxivity for Gd{sub 2}O{sub 3}NPs in comparison to gadolinium chelates which are commonly used for clinical magnetic resonance imaging. In addition, a mechanism for Gd{sub 2}O{sub 3}NPs formation and in situ surface modification of PVP-grafted Gd{sub 2}O{sub 3}NPs is proposed.

  8. New layer-based imaging and rapid prototyping techniques for computer-aided design and manufacture of custom dental restoration.

    Science.gov (United States)

    Lee, M-Y; Chang, C-C; Ku, Y C

    2008-01-01

    Fixed dental restoration by conventional methods greatly relies on the skill and experience of the dental technician. The quality and accuracy of the final product depends mostly on the technician's subjective judgment. In addition, the traditional manual operation involves many complex procedures, and is a time-consuming and labour-intensive job. Most importantly, no quantitative design and manufacturing information is preserved for future retrieval. In this paper, a new device for scanning the dental profile and reconstructing 3D digital information of a dental model based on a layer-based imaging technique, called abrasive computer tomography (ACT) was designed in-house and proposed for the design of custom dental restoration. The fixed partial dental restoration was then produced by rapid prototyping (RP) and computer numerical control (CNC) machining methods based on the ACT scanned digital information. A force feedback sculptor (FreeForm system, Sensible Technologies, Inc., Cambridge MA, USA), which comprises 3D Touch technology, was applied to modify the morphology and design of the fixed dental restoration. In addition, a comparison of conventional manual operation and digital manufacture using both RP and CNC machining technologies for fixed dental restoration production is presented. Finally, a digital custom fixed restoration manufacturing protocol integrating proposed layer-based dental profile scanning, computer-aided design, 3D force feedback feature modification and advanced fixed restoration manufacturing techniques is illustrated. The proposed method provides solid evidence that computer-aided design and manufacturing technologies may become a new avenue for custom-made fixed restoration design, analysis, and production in the 21st century.

  9. Study on microstructure of corpus striatum in patients with idiopathic rapid eye movement sleep behavior disorder using magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Ya-meng ZHANG

    2017-07-01

    Full Text Available Objective To investigate the structure of corpus striatum and the integrity of white matter fiber in patients with Parkinson's disease (PD and idiopathic rapid eye movement sleep behavior disorder (iRBD.  Methods Twelve patients with iRBD, 12 patients with PD and 10 healthy subjects that were well matched in gender, age and education were enrolled in this study. Head MRI examination was performed to all subjects to observe the changes of corpus striatum structure (the gray matter volume and the integrity of white matter fiber [fractional anisotropy (FA] by combining voxel?based morphometry (VBM and diffusion tensor imaging (DTI.  Results Compared with healthy subjects, the gray matter volume of left caudate nucleus was significantly decreased (P < 0.005, and FA values of left caudate nucleus (P < 0.005, right caudate nucleus (P < 0.001 and right putamen (P < 0.05 were all significantly reduced in iRBD patients; FA value of right putamen was significantly decreased in PD patients (P < 0.05. Compared with PD patients, the gray matter volume of left caudate nucleus of iRBD patients was significantly reduced (P < 0.001, FA values of left caudate nucleus (P < 0.01 and right caudate nucleus (P < 0.005 of iRBD patients were significantly reduced.  Conclusions There is atrophy of gray matter volume and extensive white matter fiber impairment in corpus striatum of patients with iRBD, and the white matter fiber impairment was similar to PD, which provides an anatomical evidence for iRBD being presymptom of PD. DOI: 10.3969/j.issn.1672-6731.2017.05.008

  10. Mergers + acquisitions.

    Science.gov (United States)

    Hoppszallern, Suzanna

    2002-05-01

    The hospital sector in 2001 led the health care field in mergers and acquisitions. Most deals involved a network augmenting its presence within a specific region or in a market adjacent to its primary service area. Analysts expect M&A activity to increase in 2002.

  11. Mergers & Acquisitions

    DEFF Research Database (Denmark)

    Fomcenco, Alex

    This dissertation is a legal dogmatic thesis, the goal of which is to describe and analyze the current state of law in Europe in regard to some relevant selected elements related to mergers and acquisitions, and the adviser’s counsel in this regard. Having regard to the topic of the dissertation...

  12. Unmanned aerial vehicle acquisition of three-dimensional digital image correlation measurements for structural health monitoring of bridges

    Science.gov (United States)

    Reagan, Daniel; Sabato, Alessandro; Niezrecki, Christopher

    2017-04-01

    Civil engineering structures such as bridges, buildings, and tunnels continue to be used despite aging and deterioration well past their design life. In 2013, the American Society of Civil Engineers (ASCE) rated the state of the U.S. bridges as mediocre, despite the $12.8 billion USD annually invested. Traditional inspection and monitoring techniques may produce inconsistent results, are labor intensive and too time-consuming to be considered effective for large-scale monitoring. Therefore, new structural health monitoring systems must be developed that are automated, highly accurate, minimally invasive, and cost effective. Three-dimensional (3D) digital image correlation (DIC) systems possess the capability of extracting full-field strain, displacement, and geometry profiles. Furthermore, as this measurement technique is implemented within an Unmanned Aerial Vehicle (UAV) the capability to expedite the optical-based measurement process is increased as well as the infrastructure downtime being reduced. These resulting integrity maps of the structure of interest can be easily interpreted by trained personal. Within this paper, the feasibility of performing DIC measurements using a pair of cameras installed on a UAV is shown. Performance is validated with in-flight measurements. Also, full-field displacement monitoring, 3D measurement stitching, and 3D point-tracking techniques are employed in conjunction with 3D mapping and data management software. The results of these experiments show that the combination of autonomous flight with 3D DIC and other non-contact measurement systems provides a highly valuable and effective civil inspection platform.

  13. Digital breast tomosynthesis for detecting multifocal and multicentric breast cancer: influence of acquisition geometry on model observer performance in breast phantom images

    Science.gov (United States)

    Wen, Gezheng; Park, Subok; Markey, Mia K.

    2017-03-01

    Multifocal and multicentric breast cancer (MFMC), i.e., the presence of two or more tumor foci within the same breast, has an immense clinical impact on treatment planning and survival outcomes. Detecting multiple breast tumors is challenging as MFMC breast cancer is relatively uncommon, and human observers do not know the number or locations of tumors a priori. Digital breast tomosynthesis (DBT), in which an x-ray beam sweeps over a limited angular range across the breast, has the potential to improve the detection of multiple tumors.1, 2 However, prior efforts to optimize DBT image quality only considered unifocal breast cancers (e.g.,3-9), so the recommended geometries may not necessarily yield images that are informative for the task of detecting MFMC. Hence, the goal of this study is to employ a 3D multi-lesion (ml) channelized-Hotelling observer (CHO) to identify optimal DBT acquisition geometries for MFMC. Digital breast phantoms and simulated DBT scanners of different geometries (e.g., wide or narrow arc scans, different number of projections in each scan) were used to generate image data for the simulation study. Multiple 3D synthetic lesions were inserted into different breast regions to simulate MF cases and MC cases. 3D partial least squares (PLS) channels, and 3D Laguerre-Gauss (LG) channels were estimated to capture discriminant information and correlations among signals in locally varying anatomical backgrounds, enabling the model observer to make both image-level and location-specific detection decisions. The 3D ml-CHO with PLS channels outperformed that with LG channels in this study. The simulated MC cases and MC cases were not equally difficult for the ml-CHO to detect across the different simulated DBT geometries considered in this analysis. Also, the results suggest that the optimal design of DBT may vary as the task of clinical interest changes, e.g., a geometry that is better for finding at least one lesion may be worse for counting the

  14. Four-band image mosaic of the Colorado River corridor downstream of Glen Canyon Dam in Arizona, derived from the May 2013 airborne image acquisition

    Science.gov (United States)

    Durning, Laura E.; Sankey, Joel B.; Davis, Philip A.; Sankey, Temuulen T.

    2016-12-14

    In May 2013, the U.S. Geological Survey’s Grand Canyon Monitoring and Research Center acquired airborne multispectral high-resolution data for the Colorado River in the Grand Canyon, Arizona. The image data, which consist of four color bands (blue, green, red, and near-infrared) with a ground resolution of 20 centimeters, are available to the public as 16-bit geotiff files at http://dx.doi.org/10.5066/F7TX3CHS. The images are projected in the State Plane map projection, using the central Arizona zone (202) and the North American Datum of 1983. The assessed accuracy for these data is based on 91 ground-control points and is reported at the 95-percent confidence level as 0.64 meter (m) and a root mean square error of 0.36 m. The primary intended uses of this dataset are for maps to support field data collection and simple river navigation; high-spatial-resolution change detection of sandbars, other geomorphic landforms, riparian vegetation, and backwater and nearshore habitats; and other ecosystem-wide mapping.

  15. Fast imaging employing steady-state acquisition (FIESTA) MRI to investigate cerebrospinal fluid (CSF) within dural reflections of posterior fossa cranial nerves.

    Science.gov (United States)

    Noble, David J; Scoffings, Daniel; Ajithkumar, Thankamma; Williams, Michael V; Jefferies, Sarah J

    2016-11-01

    There is no consensus approach to covering skull base meningeal reflections-and cerebrospinal fluid (CSF) therein-of the posterior fossa cranial nerves (CNs VII-XII) when planning radiotherapy (RT) for medulloblastoma and ependymoma. We sought to determine whether MRI and specifically fast imaging employing steady-state acquisition (FIESTA) sequences can answer this anatomical question and guide RT planning. 96 posterior fossa FIESTA sequences were reviewed. Following exclusions, measurements were made on the following scans for each foramen respectively (left, right); internal acoustic meatus (IAM) (86, 84), jugular foramen (JF) (83, 85) and hypoglossal canal (HC) (42, 45). A protocol describes measurement procedure. Two observers measured distances for five cases and agreement was assessed. One observer measured all the remaining cases. IAM and JF measurement interobserver variability was compared. Mean measurement difference between observers was -0.275 mm (standard deviation 0.557). IAM and JF measurements were normally distributed. Mean IAM distance was 12.2 mm [95% confidence interval (CI) 8.8-15.6]; JF was 7.3 mm (95% CI 4.0-10.6). The HC was difficult to visualize on many images and data followed a bimodal distribution. Dural reflections of posterior fossa CNs are well demonstrated by FIESTA MRI. Measuring CSF extension into these structures is feasible and robust; mean CSF extension into IAM and JF was measured. We plan further work to assess coverage of these structures with photon and proton RT plans. Advances in knowledge: We have described CSF extension beyond the internal table of the skull into the IAM, JF and HC. Oncologists planning RT for patients with medulloblastoma and ependymoma may use these data to guide contouring.

  16. T1 mapping using saturation recovery single-shot acquisition at 3-tesla magnetic resonance imaging in hypertrophic cardiomyopathy: comparison to late gadolinium enhancement.

    Science.gov (United States)

    Ogawa, Ryo; Kido, Tomoyuki; Nakamura, Masashi; Kido, Teruhito; Kurata, Akira; Uetani, Teruyoshi; Ogimoto, Akiyoshi; Miyagawa, Masao; Mochizuki, Teruhito

    2017-03-01

    We evaluated the T1 values of segments and slices and the reproducibility in healthy controls, using saturation recovery single-shot acquisition (SASHA) at 3T magnetic resonance imaging. Moreover, we examined the difference in T1 values between hypertrophic cardiomyopathy (HCM) and healthy controls, and compared those with late gadolinium enhancement (LGE). Twenty-one HCM patients and 10 healthy controls underwent T1 mapping before and after contrast administration. T1 values were measured in 12 segments. Native T1 values were significantly longer in HCM than in healthy controls [1373 ms (1312-1452 ms) vs. 1279 ms (1229-1326 ms); p T1 values were significantly longer than in healthy control segments [1366 ms (1300-1439 ms) vs. 1279 ms (1229-1326 ms); p T1 values, we differentiated between HCM and healthy controls with 95% sensitivity, 90% specificity, 94% accuracy, and an area under the curve of 0.95. Native T1 values using a SASHA at 3T could differentiate HCM from healthy controls. Moreover, native T1 values have the potential to detect abnormal myocardium that cannot be identified adequately by LGE in HCM.

  17. Imaging and quantitative data acquisition of biological cell walls with Atomic Force Microscopy and Scanning Acoustic Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tittmann, B. R. [Penn S