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1

Fourier plane image amplifier  

DOEpatents

A solid state laser is frequency tripled to 0.3 {micro}m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only about 1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power. 1 fig.

Hackel, L.A.; Hermann, M.R.; Dane, C.B.; Tiszauer, D.H.

1995-12-12

2

Fourier plane image amplifier  

DOEpatents

A solid state laser is frequency tripled to 0.3 .mu.m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only .about.1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power.

Hackel, Lloyd A. (Livermore, CA); Hermann, Mark R. (San Ramon, CA); Dane, C. Brent (Livermore, CA); Tiszauer, Detlev H. (Tracy, CA)

1995-01-01

3

Image vectorization using blue-noise sampling  

NASA Astrophysics Data System (ADS)

Current image vectorization techniques mainly deal with images with simple and plain colors. For full-color photographs, many difficulties still exist in object segmentation, feature line extraction, and color distribution reconstruction, etc. In this paper, we propose a high-efficiency image vectorization method based on importance sampling and triangulation. A set of blue-noise sampling points is first generated on the image plane by an improved error-diffusion sampling method. The point set well preserves the features in the image. Then after triangulation on this point set, color information can be recorded on the mesh vertices to form a vector image. After certain image editing, e.g. scaling or transforming, the whole image can be reconstructed by color interpolating inside each triangle. Experiments show that the method has high performing efficiency and abilities in feature-preserving. It will bring benefits to many applications, e.g. image compressing, editing, transmitting and resolution enhancement.

Zhao, Jiaojiao; Feng, Jie; Zhou, Bingfeng

2013-03-01

4

Reconnaissance with slant plane circular SAR imaging.  

PubMed

This paper presents a method for imaging from the slant plane data collected by a synthetic aperture radar (SAR) over the full rotation or a partial segment of a circular flight path. A Fourier analysis for the Green's function of the imaging system is provided. This analysis is the basis of an inversion for slant plane circular SAR data. The reconstruction algorithm and resolution for this SAR system are outlined. It is shown that the slant plane circular SAR, unlike the slant plane linear SAR, has the capability to extract three-dimensional imaging information of a target scene. The merits of the algorithm are demonstrated via a simulated target whose ultra wideband foliage penetrating (FOPEN) or ground penetrating (GPEN) ultrahigh frequency (UHF) radar signature varies with the radar's aspect angle. PMID:18285213

Soumekh, M

1996-01-01

5

Active MMW Focal Plane Imaging System  

Microsoft Academic Search

\\u000a Millimeter wave imaging technology has received a lot of attention in recent years. It has been widely applied in aircraft\\u000a landing guidance system, dangerous substance inspection, plasma tests and human carry on safety inspection. It can be applied\\u000a in many areas in the future. This paper studies an active millimeter wave focal plane imaging system. Among the theory and\\u000a key

Pingang Su; Zongxin Wang; Zhengyu Xu

2009-01-01

6

Digital image plane holography (DIPH) for two-phase flow diagnostics in multiple planes  

Microsoft Academic Search

A technique for measuring the size and displacement of the disperse phase in two planes of a two-phase flow is presented. Digital image plane holography (DIPH) is used for the simultaneous recording and independent reconstruction of both planes. Each fluid plane is illuminated with two laser sheets propagating in opposite directions. The defocused image fields are holographically recorded at 90°,

V. Palero; J. Lobera; M. P. Arroyo

2005-01-01

7

Hybrid Image-Plane/Stereo Manipulation  

NASA Technical Reports Server (NTRS)

Hybrid Image-Plane/Stereo (HIPS) manipulation is a method of processing image data, and of controlling a robotic manipulator arm in response to the data, that enables the manipulator arm to place an end-effector (an instrument or tool) precisely with respect to a target (see figure). Unlike other stereoscopic machine-vision-based methods of controlling robots, this method is robust in the face of calibration errors and changes in calibration during operation. In this method, a stereoscopic pair of cameras on the robot first acquires images of the manipulator at a set of predefined poses. The image data are processed to obtain image-plane coordinates of known visible features of the end-effector. Next, there is computed an initial calibration in the form of a mapping between (1) the image-plane coordinates and (2) the nominal three-dimensional coordinates of the noted end-effector features in a reference frame fixed to the main robot body at the base of the manipulator. The nominal three-dimensional coordinates are obtained by use of the nominal forward kinematics of the manipulator arm that is, calculated by use of the currently measured manipulator joint angles and previously measured lengths of manipulator arm segments under the assumption that the arm segments are rigid, that the arm lengths are constant, and that there is no backlash. It is understood from the outset that these nominal three-dimensional coordinates are likely to contain possibly significant calibration errors, but the effects of the errors are progressively reduced, as described next. As the end-effector is moved toward the target, the calibration is updated repeatedly by use of data from newly acquired images of the end-effector and of the corresponding nominal coordinates in the manipulator reference frame. By use of the updated calibration, the coordinates of the target are computed in manipulator-reference-frame coordinates and then used to the necessary manipulator joint angles to position and orient the end-effector at the target with respect to the same kinematic model from the calibration step. As the end-effector/target distance decreases, the computed coordinates of the end-effector and target become more nearly affected by the same errors, so that the differences between their coordinates become increasingly precise. When the end-effector reaches the target, the remaining effective position error is the distance that corresponds to more than about one pixel in the stereoscopic images of the target.

Baumgartner, Eric; Robinson, Matthew

2004-01-01

8

Digital image plane holography (DIPH) for two-phase flow diagnostics in multiple planes  

NASA Astrophysics Data System (ADS)

A technique for measuring the size and displacement of the disperse phase in two planes of a two-phase flow is presented. Digital image plane holography (DIPH) is used for the simultaneous recording and independent reconstruction of both planes. Each fluid plane is illuminated with two laser sheets propagating in opposite directions. The defocused image fields are holographically recorded at 90°, and can be reconstructed either in a defocused or in the best-focused plane. The analysis of the images in a defocused plane provides the sizes, while the cross-correlation of the focused images provides the velocity field, as in a regular particle image velocimetry (PIV) experiment. For air bubbles freely drifting in glycerine, diameters from 50 ?m to 400 ?m and displacements of up to 300 ?m have been measured.

Palero, V.; Lobera, J.; Arroyo, M. P.

2005-08-01

9

Imaging Cold Dust in the Galactic Plane  

NASA Astrophysics Data System (ADS)

Images of continuum emission at wavelengths of 850 and 1200? m from a section of the Galactic Plane near longitude 44o are presented. These data were obtained with the JCMT and SEST bolometer array receivers with beamwidths of about 14 and 22 arcsec respectively, and cover a total area of 2 square degrees. They constitute the first extensive observations of emission primarily from cold dust in a representative part of the Galaxy outside the Galactic Center. We employed complementary techniques at the two telescopes - chop/scan using SCUBA at the JCMT, and Fastscanning (direct detection) with SIMBA at the SEST - which together allow us to assess the reality of emission features where necessary. Since interstellar dust is optically thin at mm/sub-mm wavelengths these observations provide a census of dense cold dust clumps throughout the Galaxy in this direction. Twenty-seven such objects are detected in the present survey, most of which can be identified with regions of star formation. In this paper we use complementary 13CO data from the BU-FCRAO Galactic Ring Survey to determine the kinematic distances of these sources, and compare these data with images obtained in the infrared by the MSX mission. These observations presage the potential of large-scale surveys with forthcoming instrumentation, such as SCUBA2 and HARP/ACSIS at the JCMT.

Matthews, H. E.; Weferling, B.; Evans, A.; Cohen, M.; Jackson, J.; Shah, R.; Simon, R.; Jenness, T.; Davis, G. R.; Pierce-Price, D.; Dent, W. R. F.; Johnstone, D.; Richer, J. S.; Fuller, G. A.; Rathborne, J.

2004-12-01

10

Image sensor with focal plane extraction of polarimetric information  

Microsoft Academic Search

Abstract—A novel ,focal plane imaging ,sensor capable of real ,time extraction of polarization ,information is presented. The imaging ,system consists of a photo array of 256 by 256 linear current mode ,active pixel sensors (APS). Analog ,processing circuitry is included ,at the focal plane for noise suppression and computation ,of the Stokes parameters. The imaging sensor was fabricated in TSMC

Viktor Gruev; Jan Van Der Spiegel; Nader Engheta

2006-01-01

11

Metric Rectification for Perspective Images of Planes  

Microsoft Academic Search

We describe the geometry, constraints and algorithmicimplementation for metric rectification of planes. The rectificationallows metric properties, such as angles and lengthratios, to be measured on the world plane from a perspectiveimage.The novel contributions are: first, that in a stratifiedcontext the various forms of providing metric information,which include a known angle, two equal though unknownangles, and a known length ratio; can

David Liebowitz; Andrew Zisserman

1998-01-01

12

MAGPIS: The Multi-Array Galactic Plane Imaging Survey  

NSDL National Science Digital Library

The Multi-Array Galactic Plane Imaging Survey collects bits and pieces of the Galactic sky that have been imaged at high resolutions. It contains images from VLA, XMM Newton, GLIMPSE Spitzer and MSX. The website allows users to extract a section of an image from the different surveys at multiple frequencies. It also contains a publications page and catalogs constructed from radio images and other data.

White, Richard

2008-06-04

13

General image method in a plane-layered elastostatic medium  

NASA Technical Reports Server (NTRS)

The general-image method presently used to obtain the elastostatic fields in plane-layered media relies on the use of potentials in order to represent elastic fields. For the case of a single interface, this method yields the displacement field in closed form, and is applicable to antiplane, plane, and three-dimensional problems. In the case of multiplane interfaces, the image method generates the displacement fields in terms of infinite series whose convergences can be accelerated to improve method efficiency.

Fares, N.; Li, V. C.

1988-01-01

14

Focal plane resolution and overlapped array TDI imaging  

NASA Astrophysics Data System (ADS)

In this paper we model sub-pixel image registration for a generic earth-observing satellite system with a focal plane using two offset Time Delay and Integrate (TDI) arrays in the focal plane to improve the achievable ground resolution over the resolution achievable with a single array. The modeling process starts with a high-resolution image as ground truth. The Parameterized Image Chain Analysis & Simulation SOftware (PICASSO) modeling tool is used to degrade the images to match the optical transfer function, sampling, and noise characteristics of the target system. The model outputs a pair of images with a separation close to the nominal half-pixel separation between the overlapped arrays. A registration estimation algorithm is used to measure the offset for image reconstruction. The two images are aligned and summed on a grid with twice the capture resolution. We compare the resolution in images between the inputs before overlap, the reconstructed image, and a simulation for the image which would have been captured on a focal plane with twice the resolution. We find the performance to always be better than the lower resolution baseline, and to approach the performance of the high-resolution array in the ideal case. We show that the overlapped array imager significantly outperforms both the conventional high- and low-resolution imagers in conditions with high image smear.

Grycewicz, Thomas J.; Cota, Stephen A.; Lomheim, Terrence S.; Kalman, Linda S.

2008-08-01

15

Off-plane anastigmatic imaging in Offner spectrometers.  

PubMed

In this paper, the imaging performance of an Offner concentric imaging spectrometer is analyzed when the spectrometer entrance slit is disposed arbitrarily on the plane that is parallel to the grating grooves and contains the common center of curvature. Astigmatism-corrected designs are obtained for off-plane incidence on the grating if one point on the slit is located on the Rowland circle of the primary mirror. In this case, the combined system of primary mirror plus diffraction grating provides two astigmatic line images oriented parallel and orthogonal to the plane of diffraction, with the former located on the same plane as the slit. Consequently, these images can be brought to a single focus on this plane by the tertiary mirror if its radius of curvature is chosen properly. In addition, coma aberration is simultaneously removed. These results can be applied to the design of two-mirror or three-mirror spectrometers, generalizing the concept of the best imaging circle and providing solutions to get anastigmatic imaging for two object points and two wavelengths. PMID:22048301

Prieto-Blanco, Xesús; González-Nuñez, Héctor; de la Fuente, Raúl

2011-11-01

16

Blue-Green InGaN/GaN Laser Diodes on Miscut m-Plane GaN Substrate  

NASA Astrophysics Data System (ADS)

Nonpolar blue-green (481 nm) InGaN/GaN laser diodes (LDs) were realized by using m-plane GaN substrates with a misorientation angle of approximately 1° toward [0001] direction. The laser diode structures grown on miscut m-plane GaN substrates showed significantly smoother surface morphology compared to structures grown on nominally on-axis m-plane GaN substrates. It is contributed to lower threshold current densities, longer lasing wavelength, and higher lasing yield than those on on-axis substrates grown by the same growth condition. Material improvement based on the control of substrate misorientation is essential to achieve high performance LDs beyond the blue spectral range.

Lin, You-Da; Hardy, Matthew T.; Hsu, Po Shan; Kelchner, Kathryn M.; Huang, Chia-Yen; Haeger, Daniel A.; Farrell, Robert M.; Fujito, Kenji; Chakraborty, Arpan; Ohta, Hiroaki; Speck, James S.; DenBaars, Steven P.; Nakamura, Shuji

2009-08-01

17

Improved phase imaging from intensity measurements in multiple planes  

SciTech Connect

Problems stemming from quantitative phase imaging from intensity measurements play a key role in many fields of physics. Techniques based on the transport of intensity equation require an estimate of the axial derivative of the intensity to invert the problem. Derivation formulas in two adjacent planes are commonly used to experimentally compute the derivative of the irradiance. Here we propose a formula that improves the estimate of the derivative by using a higher number of planes and taking the noisy nature of the measurements into account. We also establish an upper and lower limit for the estimate error and provide the distance between planes that optimizes the estimate of the derivative.

Soto, Marcos; Acosta, Eva

2007-11-20

18

Automatic Detection of Blue-White Veil by Discrete Colour Matching in Dermoscopy Images  

E-print Network

Automatic Detection of Blue-White Veil by Discrete Colour Matching in Dermoscopy Images Ali Madooei common colours under dermoscopy, blue-grey (blue-white veil) is a strong in- dicator of malignant, to automatically detect and segment blue-white veil areas in dermoscopy images. The proposed method is an attempt

Drew, Mark S.

19

An SIS focal plane imaging array for 350 GHz  

Microsoft Academic Search

Astronomical interest in millimetre and submillimetre wavelengths (f=300 GHz to 1 THz) has fuelled the development of low noise high sensitivity detectors for these wavelengths. HARP (Heterodyne Array Receiver Project) will be a 16 element focal plane imaging array of heterodyne detectors for the 850 micron (325-375 GHz) band. Each element will consist of a mixer employing an SIS (superconductor

J. Leech; S. Withington; G. Yassin

1999-01-01

20

Prototype Focal-Plane-Array Optoelectronic Image Processor  

NASA Technical Reports Server (NTRS)

Prototype very-large-scale integrated (VLSI) planar array of optoelectronic processing elements combines speed of optical input and output with flexibility of reconfiguration (programmability) of electronic processing medium. Basic concept of processor described in "Optical-Input, Optical-Output Morphological Processor" (NPO-18174). Performs binary operations on binary (black and white) images. Each processing element corresponds to one picture element of image and located at that picture element. Includes input-plane photodetector in form of parasitic phototransistor part of processing circuit. Output of each processing circuit used to modulate one picture element in output-plane liquid-crystal display device. Intended to implement morphological processing algorithms that transform image into set of features suitable for high-level processing; e.g., recognition.

Fang, Wai-Chi; Shaw, Timothy; Yu, Jeffrey

1995-01-01

21

Characteristics of stereo images from detectors in focal plane array.  

PubMed

The equivalent ray geometry of two horizontally aligned detectors at the focal plane of the main antenna in a millimeter wave imaging system is analyzed to reveal the reason why the images from the detectors are fused as an image with a depth sense. Scanning the main antenna in both horizontal and vertical directions makes each detector perform as a camera, and the two detectors can work like a stereo camera in the millimeter wave range. However, the stereo camera geometry is different from that of the stereo camera used in the visual spectral range because the detectors' viewing directions are diverging to each other and they are a certain distance apart. The depth sense is mainly induced by the distance between detectors. The images obtained from the detectors in the millimeter imaging system are perceived with a good depth sense. The disparities responsible for the depth sense are identified in the images. PMID:21734748

Son, Jung-Young; Yeom, Seokwon; Chun, Joo-Hwan; Guschin, Vladmir P; Lee, Dong-Su

2011-07-01

22

Pupil plane multiplexing for multi-domain imaging sensors  

NASA Astrophysics Data System (ADS)

We describe an approach to polarimetric imaging based on a unique folded imaging system with an annular aperture. The novelty of this approach lies in the system's collection architecture, which segments the pupil plane to measure the individual polarimetric components contributing to the Stokes vectors. Conventional approaches rely on time sequential measurements (time-multiplexed) using a conventional imaging architecture with a reconfigurable polarization filter, or measurements that segment the focal plane array (spatial multiplexing) by super-imposing an array of polarizers. Our approach achieves spatial multiplexing within the aperture in a compact, lightweight design. The aperture can be configured for sequential collection of the four polarization components required for Stokes vector calculation or in any linear combination of those components on a common focal plane array. Errors in calculating the degree of polarization caused by the manner in which the aperture is partitioned are analyzed, and approaches for reducing that error are investigated. It is shown that reconstructing individual polarization filtered images prior to calculating the Stokes parameters can reduce the error significantly.

Horstmeyer, Roarke; Euliss, Gary W.; Athale, Ravindra A.; Morrison, Rick L.; Stack, Ronald A.; Ford, Joseph

2008-08-01

23

Endoanal MRI of perianal fistulas: the optimal imaging planes  

Microsoft Academic Search

.   Twenty consecutive patients with the clinical suspicion of a perianal fistula were studied to define the optimal and time-efficient\\u000a imaging planes for endoanal MRI in the identification and classification of perianal fistulas. The duration of each part of\\u000a the MR procedure was recorded in all patients. Off-axis axial (A), coronal (C), sagittal (S) and radial (R) T2-weighted sequences\\u000a were

J. Stoker; V. E. Jong Tjien Fa; M. J. C. Eijkemans; W. R. Schouten; J. S. Laméris

1998-01-01

24

Transesophageal echocardiographic imaging workshop: a basic transverse plane examination sequence.  

PubMed Central

This workshop describes a 10-step sequence of transverse plane two-dimensional transesophageal echocardiographic views of the heart and great vessels that constitutes a basic standardized examination capable of being performed by a beginning practitioner. Images Figure 3 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 PMID:10604784

Griffin, M.; Rafferty, T.; Rogers, A.; Prielipp, R.

1998-01-01

25

Stolt's f-k migration for plane wave ultrasound imaging.  

PubMed

Ultrafast ultrasound is an emerging modality that offers new perspectives and opportunities in medical imaging. Plane wave imaging (PWI) allows one to attain very high frame rates by transmission of planar ultrasound wave-fronts. As a plane wave reaches a given scatterer, the latter becomes a secondary source emitting upward spherical waves and creating a diffraction hyperbola in the received RF signals. To produce an image of the scatterers, all the hyperbolas must be migrated back to their apexes. To perform beamforming of plane wave echo RFs and return high-quality images at high frame rates, we propose a new migration method carried out in the frequency-wavenumber (f-k) domain. The f-k migration for PWI has been adapted from the Stolt migration for seismic imaging. This migration technique is based on the exploding reflector model (ERM), which consists in assuming that all the scatterers explode in concert and become acoustic sources. The classical ERM model, however, is not appropriate for PWI. We showed that the ERM can be made suitable for PWI by a spatial transformation of the hyperbolic traces present in the RF data. In vitro experiments were performed to outline the advantages of PWI with Stolt's f-k migration over the conventional delay-and-sum (DAS) approach. The Stolt's f-k migration was also compared with the Fourier-based method developed by J.-Y. Lu. Our findings show that multi-angle compounded f-k migrated images are of quality similar to those obtained with a stateof- the-art dynamic focusing mode. This remained true even with a very small number of steering angles, thus ensuring a highly competitive frame rate. In addition, the new FFT-based f-k migration provides comparable or better contrast-to-noise ratio and lateral resolution than the Lu's and DAS migration schemes. Matlab codes for the Stolt's f-k migration for PWI are provided. PMID:24626107

Garcia, Damien; Le Tarnec, Louis; Muth, Stéphan; Montagnon, Emmanuel; Porée, Jonathan; Cloutier, Guy

2013-09-01

26

Electronics for Fast Vertex Position Measurement and Medical Imaging Topic 34b Blue Sky Electronics, LLC  

E-print Network

Electronics for Fast Vertex Position Measurement and Medical Imaging Topic 34b Blue Sky Electronics, LLC Blue Sky Electronics, LLC 401 Studewood, Ste. 203 Houston, TX 77007 PI: Lloyd Bridges #12;Electronics for Fast Vertex Position Measurement and Medical Imaging Topic 34b Blue Sky Electronics, LLC 11

Llope, William J.

27

Radiometric infrared focal plane array imaging system for thermographic applications  

NASA Astrophysics Data System (ADS)

This document describes research performed under the Radiometric Infrared Focal Plane Array Imaging System for Thermographic Applications contract. This research investigated the feasibility of using platinum silicide (PtSi) Schottky-barrier infrared focal plane arrays (IR FPAs) for NASA Langley's specific radiometric thermal imaging requirements. The initial goal of this design was to develop a high spatial resolution radiometer with an NETD of 1 percent of the temperature reading over the range of 0 to 250 C. The proposed camera design developed during this study and described in this report provides: (1) high spatial resolution (full-TV resolution); (2) high thermal dynamic range (0 to 250 C); (3) the ability to image rapid, large thermal transients utilizing electronic exposure control (commandable dynamic range of 2,500,000:1 with exposure control latency of 33 ms); (4) high uniformity (0.5 percent nonuniformity after correction); and (5) high thermal resolution (0.1 C at 25 C background and 0.5 C at 250 C background).

Esposito, B. J.; McCafferty, N.; Brown, R.; Tower, J. R.; Kosonocky, W. F.

1992-11-01

28

Stolt's f-k migration for plane wave ultrasound imaging  

PubMed Central

Ultrafast ultrasound is an emerging modality that offers new perspectives and opportunities in medical imaging. Plane wave imaging (PWI) allows one to attain very high frame rates by transmission of planar ultrasound wavefronts. As a plane wave reaches a given scatterer, the latter becomes a secondary source emitting upward spherical waves and creating a diffraction hyperbola in the received RF (radio-frequency) signals. To produce an image of the scatterers, all the hyperbolas must be migrated back to their apexes. In order to perform beamforming of plane wave echo RFs and return high-quality images at high frame rates, we propose a new migration method carried out in the frequency-wavenumber (f-k) domain. The f-k migration for PWI has been adapted from the Stolt migration for seismic imaging. This migration technique is based on the exploding reflector model (ERM), which consists in assuming that all the scatterers explode in concert and become acoustic sources. The classical ERM model, however, is not appropriate for PWI. We showed that the ERM can be made suitable for PWI by a spatial transformation of the hyperbolic traces present in the RF data. In vitro experiments were performed to sketch the advantages of PWI with Stolt’s f-k migration over the conventional delay-and-sum (DAS) approach. The Stolt’s f-k migration was also compared with the Fourier-based method developed by J-Y Lu. Our findings show that multi-angle compounded f-k migrated images are of quality similar to those obtained with a state-of-the-art dynamic focusing mode. This remained true even with a very small number of steering angles thus ensuring a highly competitive frame rate. In addition, the new FFT-based f-k migration provides comparable or better contrast-to-noise ratio and lateral resolution than the Lu’s and DAS migration schemes. Matlab codes of the Stolt’s f-k migration for PWI are provided. PMID:24626107

Garcia, Damien; Le Tarnec, Louis; Muth, Stephan; Montagnon, Emmanuel; Poree, Jonathan; Cloutier, Guy

2013-01-01

29

Blue Marble - A Seamless Image Mosaic of the Earth (WMS)  

NSDL National Science Digital Library

This spectacular Blue Marble image is the most detailed true-color image of the entire Earth to date. Using a collection of satellite-based observations, scientists and visualizers stitched together months of observations of the land surface, oceans, sea ice, and clouds into a seamless, true-color mosaic of every square kilometer (.386 square mile) of our planet. Much of the information contained in this image came from a single remote-sensing device-NASAs Moderate Resolution Imaging Spectroradiometer, or MODIS. Flying over 700 km above the Earth onboard the Terra satellite, MODIS provides an integrated tool for observing a variety of terrestrial, oceanic, and atmospheric features of the Earth. The land and coastal ocean portions of these images are based on surface observations collected from June through September 2001 and combined, or composited, every eight days to compensate for clouds that might block the sensors view of the surface on any single day. Two different types of ocean data were used in these images: shallow water true color data, and global ocean color (or chlorophyll) data. Topographic shading is based on the GTOPO 30 elevation dataset compiled by the U.S. Geological Surveys EROS Data Center.

Stockli, Reto; King, Michael

2004-02-16

30

Imaging Polarimetry With Polarization-Sensitive Focal Planes  

NASA Astrophysics Data System (ADS)

We present a compact, lightweight, snapshot imaging polarimeter designed for operation in the near-infrared (NIR) and mid-infrared (MIR). Flux, polarization and spectral energy distribution are the fundamental measurements through which we infer properties of the sources of radiation such as intensity, temperature, chemical composition, emission mechanisms and structure. In recent decades, many scientific fields that utilize radiometry and spectroscopy have benefited from revolutionary improvements in instrumentation, for example, charge-coupled devices, hybridized infrared arrays, multi-object spectrometers and adaptive optics. Advances in polarimetric instrumentation have been more modest. Recently, the fabrication of microgrid polarizer arrays (MGPAs), facilitated the development of polarization-sensitive focal planes. These devices have inherent capability to measure the degree and angle of polarization across a scene (i.e., imaging polarimetry) instantaneously, without the need for multiple exposures and moving optics or multiple detectors. MGPA-based devices are compact, lightweight, and mechanically robust and perfectly suited for deployment on space-based and airborne platforms. We describe the design, operation and expected performance of MGPA-based imaging polarimeters and identify the applications for which these polarimeters are best suited.

Vorobiev, Dmitry; Ninkov, Z.

2014-01-01

31

MAGPIS: A Multi-Array Galactic Plane Imaging Survey  

E-print Network

We present the Multi-Array Galactic Plane Imaging Survey (MAGPIS), which maps portions of the first Galactic quadrant with an angular resolution, sensitivity and dynamic range that surpasses existing radio images of the Milky Way by more than an order of magnitude. The source detection threshold at 20 cm is in the range 1--2 mJy over the 85% of the survey region (5 deg atlas of ~400 diffuse emission regions. New and archival data at 90 cm for the whole survey area are also presented. Comparison of our catalogs and images with the MSX mid-infrared data allow us to provide preliminary discrimination between thermal and non-thermal sources. We identify 49 high-probability supernova remnant candidates, increasing by a factor of seven the number of known remnants with diameters smaller than 5 arcmin in the survey region; several are pulsar wind nebula candidates and/or very small diameter remnants (D<45 arcsec). We report the tentative identification of several hundred H II regions based on a comparison with the mid-IR data; they range in size from unresolved ultra-compact sources to large complexes of diffuse emission on scales of half a degree. In several of the latter regions, cospatial nonthermal emission illustrates the interplay between stellar death and birth. We comment briefly on plans for followup observations and our extension of the survey; when complemented by data from ongoing X-ray and mid-IR observations, we expect MAGPIS to provide the most complete census yet obtained of the birth and death of massive stars in the Milky Way. Catalogs and images are available on the MAGPIS web site (http://third.ucllnl.org/gps).

David J. Helfand; Robert H. Becker; Richard L. White; Adam Fallon; Sarah Tuttle

2005-10-16

32

Application of bit-plane decomposition steganography to wavelet encoded images  

Microsoft Academic Search

This paper presents a steganography method based on a lossy wavelet compression scheme and bit-plane complex- ity segmentation (BPCS) steganography. This method uti- lizes the embedded zerotree wavelet (EZW) compression scheme, where wavelet coefficients of an image are quan- tized into a bit-plane structure. The proposed steganogra- phy enables us to use lossy compressed images as dummy files in bit-plane-based

H. Noda; J. Spaulding; Mahdad Nouri Shirazi; E. Kawaguchi

2002-01-01

33

Depth-enhanced integral imaging display system with electrically variable image planes using polymer-dispersed liquid-crystal layers.  

PubMed

A depth-enhanced three-dimensional integral imaging system with electrically variable image planes is proposed. For implementing the variable image planes, polymer-dispersed liquid-crystal (PDLC) films and a projector are adopted as a new display system in the integral imaging. Since the transparencies of PDLC films are electrically controllable, we can make each film diffuse the projected light successively with a different depth from the lens array. As a result, the proposed method enables control of the location of image planes electrically and enhances the depth. The principle of the proposed method is described, and experimental results are also presented. PMID:17538673

Kim, Yunhee; Choi, Heejin; Kim, Joohwan; Cho, Seong-Woo; Kim, Youngmin; Park, Gilbae; Lee, Byoungho

2007-06-20

34

EXTENDED DEPTH-OF-FIELD USING ADJACENT PLANE DEBLURRING AND MPP WAVELET FUSION FOR MICROSCOPE IMAGES  

E-print Network

to accurately measure the size, shape, and boundary of a blurred object. As a result, several optical sections of directly fusing optical sections, we preprocess the images by performing adjacent plane deblurring fusion. Image fu- sion is a technique that combines several input images into a single composite image

Texas at Austin, University of

35

LEARNING-BASED SCAN PLANE IDENTIFICATION FROM FETAL HEAD ULTRASOUND IMAGES  

E-print Network

-dimensional ultrasound is routinely used in obstetric applications to monitor fetal development. Ultra- soundLEARNING-BASED SCAN PLANE IDENTIFICATION FROM FETAL HEAD ULTRASOUND IMAGES Xiaoming Liua, Pavan-based algorithm to identify an acceptable fetal head scan plane. We divide the problem into cranium detection

36

Focal plane wave-front sensing algorithm for high-contrast imaging  

Microsoft Academic Search

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its\\u000a bright parent star. A major limitation for such direct imaging is the speckle noise that is induced from the wave-front error\\u000a of an optical system. We derive an algorithm for the wave-front measurement directly from 3 focal plane images. The 3 images

Jiangpei Dou; Deqing Ren; Yongtian Zhu; Xi Zhang

2009-01-01

37

The application of digital image plane holography technology to identify Chinese herbal medicine  

NASA Astrophysics Data System (ADS)

In this paper, the imaging technology of digital image plane holography to identify the Chinese herbal medicine is studied. The optical experiment system of digital image plane holography which is the special case of pre-magnification digital holography was built. In the record system, one is an object light by using plane waves which illuminates the object, and the other one is recording hologram by using spherical light wave as reference light. There is a Micro objective lens behind the object. The second phase factor which caus ed by the Micro objective lens can be eliminated by choosing the proper position of the reference point source when digital image plane holography is recorded by spherical light. In this experiment, we use the Lygodium cells and Onion cells as the object. The experiment results with Lygodium cells and Onion cells show that digital image plane holography avoid the process of finding recording distance by using auto-focusing approach, and the phase information of the object can be reconstructed more accurately. The digital image plane holography is applied to the microscopic imaging of cells more effectively, and it is suit to apply for the identify of Chinese Herbal Medicine. And it promotes the application of digital holographic in practice.

Wang, Huaying; Guo, Zhongjia; Liao, Wei; Zhang, Zhihui

2012-03-01

38

The application of digital image plane holography technology to identify Chinese herbal medicine  

NASA Astrophysics Data System (ADS)

In this paper, the imaging technology of digital image plane holography to identify the Chinese herbal medicine is studied. The optical experiment system of digital image plane holography which is the special case of pre-magnification digital holography was built. In the record system, one is an object light by using plane waves which illuminates the object, and the other one is recording hologram by using spherical light wave as reference light. There is a Micro objective lens behind the object. The second phase factor which caus ed by the Micro objective lens can be eliminated by choosing the proper position of the reference point source when digital image plane holography is recorded by spherical light. In this experiment, we use the Lygodium cells and Onion cells as the object. The experiment results with Lygodium cells and Onion cells show that digital image plane holography avoid the process of finding recording distance by using auto-focusing approach, and the phase information of the object can be reconstructed more accurately. The digital image plane holography is applied to the microscopic imaging of cells more effectively, and it is suit to apply for the identify of Chinese Herbal Medicine. And it promotes the application of digital holographic in practice.

Wang, Huaying; Guo, Zhongjia; Liao, Wei; Zhang, Zhihui

2011-11-01

39

ImagePlane: an automated image analysis pipeline for high-throughput screens using the planarian Schmidtea mediterranea.  

PubMed

ImagePlane is a modular pipeline for automated, high-throughput image analysis and information extraction. Designed to support planarian research, ImagePlane offers a self-parameterizing adaptive thresholding algorithm; an algorithm that can automatically segment animals into anterior-posterior/left-right quadrants for automated identification of region-specific differences in gene and protein expression; and a novel algorithm for quantification of morphology of animals, independent of their orientations and sizes. ImagePlane also provides methods for automatic report generation, and its outputs can be easily imported into third-party tools such as R and Excel. Here we demonstrate the pipeline's utility for identification of genes involved in stem cell proliferation in the planarian Schmidtea mediterranea. Although designed to support planarian studies, ImagePlane will prove useful for cell-based studies as well. PMID:23822514

Flygare, Steven; Campbell, Michael; Ross, Robert Mars; Moore, Barry; Yandell, Mark

2013-08-01

40

Focal plane resolution and overlapped array time delay and integrate imaging  

NASA Astrophysics Data System (ADS)

In this paper we model sub-pixel image registration for a generic earth-observing satellite system with a focal plane using two offset time delay and integrate (TDI) arrays in the focal plane to improve the achievable ground resolution over the resolution achievable with a single array. The modeling process starts with a high-resolution image as ground truth. The Parameterized Image Chain Analysis & Simulation Software (PICASSO) modeling tool is used to degrade the images to match the optical transfer function, sampling, and noise characteristics of the target system. The model outputs a pair of images with a separation close to the nominal half-pixel separation between the overlapped arrays. A registration estimation algorithm is used to measure the offset for image reconstruction. The two images are aligned and summed on a grid with twice the capture resolution. We compare the resolution in images between the inputs before overlap, the reconstructed image, and a simulation for the image which would have been captured on a focal plane with twice the resolution. We find the performance to always be better than the lower resolution baseline, and to approach the performance of the high-resolution array in the ideal case. We show that the overlapped array imager significantly outperforms both the conventional high- and low-resolution imagers in conditions with high image smear.

Grycewicz, Thomas J.; Cota, Stephen A.; Lomheim, Terrence S.; Kalman, Linda S.

2010-06-01

41

UNIFYING IMAGE PLANE LIFTINGS FOR CENTRAL CATADIOPTRIC AND DIOPTRIC CAMERAS  

E-print Network

projection of a line is a conic section. A unifying theory for central catadioptric systems has been proposed the division model, the image of a line is in general a conic curve. 2. For both catadioptric and radially

Barreto, Joao

42

Rapid three-dimensional isotropic imaging of living cells using Bessel beam plane illumination  

PubMed Central

A key challenge when imaging living cells is how to noninvasively extract the most spatiotemporal information possible. Unlike popular wide-field and confocal methods, plane-illumination microscopy limits excitation to the information-rich vicinity of the focal plane, providing effective optical sectioning and high speed while minimizing out-of-focus background and premature photobleaching. Here we used scanned Bessel beams in conjunction with structured illumination and/or two-photon excitation to create thinner light sheets (<0.5 ?m) better suited to three-dimensional (3D) subcellular imaging. As demonstrated by imaging the dynamics of mitochondria, filopodia, membrane ruffles, intracellular vesicles and mitotic chromosomes in live cells, the microscope currently offers 3D isotropic resolution down to ~0.3 ?m, speeds up to nearly 200 image planes per second and the ability to noninvasively acquire hundreds of 3D data volumes from single living cells encompassing tens of thousands of image frames. PMID:21378978

Planchon, Thomas A; Gao, Liang; Milkie, Daniel E; Davidson, Michael W; Galbraith, James A; Galbraith, Catherine G; Betzig, Eric

2012-01-01

43

Close-up imaging using microcamera arrays for focal plane synthesis  

NASA Astrophysics Data System (ADS)

Conventional close-up imaging uses lens arrays to form a continuous image of an extended object on a single focal plane sensor or photographic film. By imaging using microcamera arrays onto many separate sensors rather than a single large sensor, the subfields captured by individual sensors may be combined using image processing into a large synthetic image plane. This greatly increases the flexibility of the close-up imaging design because it is no longer required that the close up image be continuous. Using microcamera arrays, hundreds or thousands of megapixel sensors may be combined to form a synthetic gigapixel-scale sensor. This paper is an investigation into the design issues of microcamera arrays, and presents a simple design of a lens suitable for a megapixel class microcamera.

Marks, Daniel L.; Brady, David J.

2011-03-01

44

Quantitative Characterization of Super-Resolution Infrared Imaging Based on Time-Varying Focal Plane Coding  

NASA Astrophysics Data System (ADS)

High resolution infrared image has been the goal of an infrared imaging system. In this paper, a super-resolution infrared imaging method using time-varying coded mask is proposed based on focal plane coding and compressed sensing theory. The basic idea of this method is to set a coded mask on the focal plane of the optical system, and the same scene could be sampled many times repeatedly by using time-varying control coding strategy, the super-resolution image is further reconstructed by sparse optimization algorithm. The results of simulation are quantitatively evaluated by introducing the Peak Signal-to-Noise Ratio (PSNR) and Modulation Transfer Function (MTF), which illustrate that the effect of compressed measurement coefficient r and coded mask resolution m on the reconstructed image quality. Research results show that the proposed method will promote infrared imaging quality effectively, which will be helpful for the practical design of new type of high resolution ! infrared imaging systems.

Wang, X.; Yuan, Y.; Zhang, J.; Chen, Y.; Cheng, Y.

2014-10-01

45

Inter-plane artifact suppression in tomosynthesis using 3D CT image data  

PubMed Central

Background Despite its superb lateral resolution, flat-panel-detector (FPD) based tomosynthesis suffers from low contrast and inter-plane artifacts caused by incomplete cancellation of the projection components stemming from outside the focal plane. The incomplete cancellation of the projection components, mostly due to the limited scan angle in the conventional tomosynthesis scan geometry, often makes the image contrast too low to differentiate the malignant tissues from the background tissues with confidence. Methods In this paper, we propose a new method to suppress the inter-plane artifacts in FPD-based tomosynthesis. If 3D whole volume CT images are available before the tomosynthesis scan, the CT image data can be incorporated into the tomosynthesis image reconstruction to suppress the inter-plane artifacts, hence, improving the image contrast. In the proposed technique, the projection components stemming from outside the region-of-interest (ROI) are subtracted from the measured tomosynthesis projection data to suppress the inter-plane artifacts. The projection components stemming from outside the ROI are calculated from the 3D whole volume CT images which usually have lower lateral resolution than the tomosynthesis images. The tomosynthesis images are reconstructed from the subtracted projection data which account for the x-ray attenuation through the ROI. After verifying the proposed method by simulation, we have performed both CT scan and tomosynthesis scan on a phantom and a sacrificed rat using a FPD-based micro-CT. Results We have measured contrast-to-noise ratio (CNR) from the tomosynthesis images which is an indicator of the residual inter-plane artifacts on the focal-plane image. In both cases of the simulation and experimental imaging studies of the contrast evaluating phantom, CNRs have been significantly improved by the proposed method. In the rat imaging also, we have observed better visual contrast from the tomosynthesis images reconstructed by the proposed method. Conclusions The proposed tomosynthesis technique can improve image contrast with aids of 3D whole volume CT images. Even though local tomosynthesis needs extra 3D CT scanning, it may find clinical applications in special situations in which extra 3D CT scan is already available or allowed. PMID:22151538

2011-01-01

46

Unifying Image Plane Liftings for Central Catadioptric and Dioptric Cameras  

Microsoft Academic Search

In this paper, we study projection systems with a single viewpoint, including combinations of mirrors and lenses (catadioptric) as well as just lenses with or without radial distortion (dioptric systems). Firstly, we extend a well- known unifying model for catadioptric systems to incorporate a class of dioptric systems with radial distortion. Secondly, we provide a new representation for the image

Joao P. Barreto; Kostas Daniilidis

47

Full-color image-plane holographic video display  

Microsoft Academic Search

In this paper, we have investigated real time calculation and display optics of full color hologram with full parallax. In our previous study, full color hologram was realized as the rainbow hologram which discards vertical parallax to reduce computation complexity. Since the color of the reconstructed image changes when observer moves to the vertical direction even a little, proper color

Takeshi Yamaguchi; Gen Okabe; Hiroshi Yoshikawa

2007-01-01

48

The autocorrelation function of polychromatic laser speckle patterns near the image plane  

Microsoft Academic Search

The autocorrelation function of polychromatic speckle patterns produced near the image plane of a double diffraction imaging system is experimentally studied. The condition under which the polychromatic speckle field obeys Gaussian statistics is further investigated as a function of the numberN of scattering cells, using the average contrast of the speckle intensity fluctuations. The profile of the autocorrelation function is

N. Nagamatsu; K. Nakagawa; T. Asakura; K. Morishita

1983-01-01

49

GPU-based beamformer: Fast realization of plane wave compounding and synthetic aperture imaging  

Microsoft Academic Search

Although they show potential to improve ultra- sound image quality, plane wave (PW) compounding and syn- thetic aperture (SA) imaging are computationally demanding and are known to be challenging to implement in real-time. In this work, we have developed a novel beamformer architecture with the real-time parallel processing capacity needed to en- able fast realization of PW compounding and SA

Billy S. Yiu; Ivan H. Tsang; Alfred H. Yu

2011-01-01

50

Application of bit-plane decomposition steganography to JPEG2000 encoded images  

Microsoft Academic Search

This letter presents a steganography method based on a JPEG2000 lossy compression scheme and bit-plane complexity segmentation (BPCS) steganography. It overcomes the lack of robustness of bit-plane-based steganography methods with respect to lossy compression of a dummy image: a critical shortcoming that has hampered deployment in a practical scenario. The proposed method is based on a seamless integration of the

Hideki Noda; Jeremiah Spaulding; Mahdad N. Shirazi; Eiji Kawaguchi

2002-01-01

51

Coronagraphic phase diversity: a simple focal plane sensor for high-contrast imaging.  

PubMed

Exoplanet direct imaging is a challenging goal of today's astronomical instrumentation. Several high-contrast imaging instruments dedicated to this task are currently being integrated; they are ultimately limited by the presence of quasi-static speckles in the imaging focal plane. These speckles originate in residual quasi-static optical aberrations, which must be measured and compensated for, typically at a nanometric level. We present a novel focal plane wavefront sensor (WFS) designed for this particular application. It is an extension of the phase diversity technique to coronagraphic imaging. This sensor requires no dedicated hardware and uses only two scientific images differing from a known aberration, which can be conveniently introduced by the adaptive optics subsystem. The aberrations are therefore calibrated all the way down to the scientific camera, without any differential aberrations between the sensor and the scientific camera. We show the potential of this WFS by means of simulations, and we perform a preliminary experimental validation. PMID:23202053

Sauvage, J-F; Mugnier, L; Paul, B; Villecroze, R

2012-12-01

52

Extended linear detection range for optical tweezers using image-plane detection scheme  

NASA Astrophysics Data System (ADS)

Ability to measure pico- and femto-Newton range forces using optical tweezers (OT) strongly relies on the sensitivity of its detection system. We show that the commonly used back-focal-plane detection method provides a linear response range which is shorter than that of the restoring force of OT for large beads. This limits measurable force range of OT. We show, both theoretically and experimentally, that utilizing a second laser beam for tracking could solve the problem. We also propose a new detection scheme in which the quadrant photodiode is positioned at the plane optically conjugate to the object plane (image plane). This method solves the problem without need for a second laser beam for the bead sizes that are commonly used in force spectroscopy applications of OT, such as biopolymer stretching.

Hajizadeh, Faegheh; Masoumeh Mousavi, S.; Khaksar, Zeinab S.; Reihani, S. Nader S.

2014-10-01

53

GP-grid image interpolation and denoising for division of focal plane sensors  

NASA Astrophysics Data System (ADS)

Image interpolation and denoising are important techniques in image processing. Recently, there has been a growing interest in the use of Gaussian processes (GP) regression for interpolation and denoising of image data. However, exact GP regression suffers from 0 (N3) runtime for data size N, making it intractable for image data. Our GP-grid algorithm reduces the runtime complexity of GP from 0 (N3) to 0 (N312). We provide comprehensive mathematical model as well as experimental results of the GP interpolation performance for division of focal plane polarimeter. The GP interpolation method outperforms the commonly used bilinear interpolation method for polarimeters.

Gilboa, Elad; Cunningham, John P.; Nehorai, Arye; Gruev, Viktor

2014-05-01

54

Focal-Plane Image and Beam Quality Sensors for Adaptive Optics  

E-print Network

Focal-Plane Image and Beam Quality Sensors for Adaptive Optics Marc CohenÝ, Gert Cauwenberghs Laboratory, Adelphi, MD 20783 Abstract Control of adaptive optical elements for real-time wavefront phase to the requirements of high resolution, real-time adaptive optical systems. In this paper we introduce two VLSI focal

Cauwenberghs, Gert

55

Polarized spontaneous emission from blue-green m-plane GaN-based light emitting diodes  

NASA Astrophysics Data System (ADS)

The polarization of spontaneous emission was investigated for various indium compositions and quantum wells on m-plane oriented gallium nitride (GaN) light emitting diodes (LEDs) grown on bulk-GaN substrates. Internal light scattering and depolarization was mitigated with application of absorber materials to the LED die. The polarization ratio (?) was measured under electrical injection for devices with InGaN active regions emitting up to 520 nm and observed as high as 96%. Values of ? were independent of drive current. The valence band energy separation (?E) was characterized using spectral measurement and temperature dependent optical analysis of valence band hole distributions.

Brinkley, Stuart E.; Lin, You-Da; Chakraborty, Arpan; Pfaff, Nathan; Cohen, Daniel; Speck, James S.; Nakamura, Shuji; DenBaars, Steven P.

2011-01-01

56

A blue optical filter for narrow-band imaging in endoscopic capsules  

NASA Astrophysics Data System (ADS)

This paper presents the design, simulation, fabrication, and characterization of a thin-film Fabry-Perot resonator composed of titanium dioxide (TiO2) and silicon dioxide (SiO2) thin-films. The optical filter is developed to be integrated with a light emitting diode (LED) for enabling narrow-band imaging (NBI) in endoscopy. The NBI is a high resolution imaging technique that uses spectrally centered blue light (415 nm) and green light (540 nm) to illuminate the target tissue. The light at 415 nm enhances the imaging of superficial veins due to their hemoglobin absorption, while the light at 540 nm penetrates deeper into the mucosa, thus enhances the sub-epithelial vessels imaging. Typically the endoscopes and endoscopic capsules use white light for acquiring images of the gastrointestinal (GI) tract. However, implementing the NBI technique in endoscopic capsules enhances their capabilities for the clinical applications. A commercially available blue LED with a maximum peak intensity at 404 nm and Full Width Half Maximum (FWHM) of 20 nm is integrated with a narrow band blue filter as the NBI light source. The thin film simulations show a maximum spectral transmittance of 36 %, that is centered at 415 nm with FWHM of 13 nm for combined the blue LED and a Fabry Perot resonator system. A custom made deposition scheme was developed for the fabrication of the blue optical filter by RF sputtering. RF powered reactive sputtering at 200 W with the gas flows of argon and oxygen that are controlled for a 5:1 ratio gives the optimum optical conditions for TiO2 thin films. For SiO2 thin films, a non-reactive RF sputtering at 150 W with argon gas flow at 15 sccm results in the best optical performance. The TiO2 and SiO2 thin films were fully characterized by an ellipsometer in the wavelength range between 250 nm to 1600 nm. Finally, the optical performance of the blue optical filter is measured and presented.

Silva, M. F.; Ghaderi, M.; Goncalves, L. M.; de Graaf, G.; Wolffenbuttel, R. F.; Correia, J. H.

2014-05-01

57

Spatially isotropic four-dimensional imaging with dual-view plane illumination microscopy  

PubMed Central

Optimal four-dimensional imaging requires high spatial resolution in all dimensions, high speed and minimal photobleaching and damage. We developed a dual-view, plane illumination microscope with improved spatiotemporal resolution by switching illumination and detection between two perpendicular objectives in an alternating duty cycle. Computationally fusing the resulting volumetric views provides an isotropic resolution of 330 nm. As the sample is stationary and only two views are required, we achieve an imaging speed of 200 images/s (i.e., 0.5 s for a 50-plane volume). Unlike spinning-disk confocal or Bessel beam methods, which illuminate the sample outside the focal plane, we maintain high spatiotemporal resolution over hundreds of volumes with negligible photobleaching. To illustrate the ability of our method to study biological systems that require high-speed volumetric visualization and/or low photobleaching, we describe microtubule tracking in live cells, nuclear imaging over 14 h during nematode embryogenesis and imaging of neural wiring during Caenorhabditis elegans brain development over 5 h. PMID:24108093

Wu, Yicong; Wawrzusin, Peter; Senseney, Justin; Fischer, Robert S; Christensen, Ryan; Santella, Anthony; York, Andrew G; Winter, Peter W; Waterman, Clare M; Bao, Zhirong; Colon-Ramos, Daniel A; McAuliffe, Matthew; Shroff, Hari

2014-01-01

58

Out-of-plane light-scattering polarimetric imaging of a thread surface  

NASA Astrophysics Data System (ADS)

A novel polarimetric measurement based on hemispherical light-scattering for the assessment of superficial screw is presented. The optical system is capable of capturing polarized light images. The effect of the thread surface backscattering is estimated with the use of in-plane and out-of-plane illumination. The angular distributions of polarized light scattered by the ISO metric screws are measured for light incident from a green laser. A partial Stokes vector imaging detector is mounted on a motorized rotating arm at an oblique angle to the sample normal and consists of a 10-bit scientific camera, an object lens, and a polarizer. The partial Stokes vector images of light scattered towards the camera are generated for each direction and a useful decomposition of the partial Stokes vector is presented. The thread surface effects can be minimized using out-of-plane polarized illumination in conjunction with polarized images. The experimental result may provide a new polarized imaging technique for using visible light to inspect the key features of a screw in automated optical inspection system.

Liu, Cheng-Yang; Chang, Li-Jen

2014-12-01

59

Magneto-optic imaging: Normal and parallel field components of in-plane magnetized samples  

NASA Astrophysics Data System (ADS)

Magneto-optical (MO) imaging has become a powerful tool for determining magnetic properties of materials by detecting the stray magnetic fields. The technique consists in measuring the Faraday rotation, ?F, in the light polarization plane when light travels through a transparent sensitive garnet (ferrite garnet film, FGF) placed in close contact to the sample. For in-plane magnetized samples, the MO image is not trivially related to the sample magnetization, and to contribute to this understanding we have imaged commercial audio tapes in which computer-generated functions were recorded. We present MO images of periodically in-plane magnetized tapes with square, sawtooth, triangular and sinusoidal waveforms, for which we analytically calculate the perpendicular and parallel stray magnetic field components generated by the tape. As a first approach we correlate the measured light intensity with the perpendicular magnetic field component at the FGF, and we show that it can be approximated to the gradient of the sample magnetization. A more detailed calculation, taking into account the effect of both field components in the Faraday rotation, is presented and satisfactorily compared with the obtained MO images. The presence of magnetic domains in the garnet is shown to be related to the change in sign of the parallel component of the stray magnetic field, which can be approximated to the second derivative of the sample magnetization.

Ferrari, H.; Bekeris, V.; Thibeault, M.; Johansen, T. H.

2007-06-01

60

Maximum likelihood blind image separation using nonsymmetrical half-plane Markov random fields.  

PubMed

This paper presents a maximum likelihood approach for blindly separating linear instantaneous mixtures of images. The spatial autocorrelation within each image is described using nonsymmetrical half-plane (NSHP) Markov random fields in order to simplify the joint probability density functions of the source images. A first implementation assuming stationary sources is presented. It is then extended to a more realistic nonstationary image model: two approaches, respectively based on blocking and kernel smoothing, are proposed to cope with the nonstationarity of the images. The estimation of the mixing matrix is performed using an iterative equivariant version of the Newton-Raphson algorithm. Moreover, score functions, required for the computation of the updating rule, are approximated at each iteration by parametric polynomial estimators. Results achieved with artificial mixtures of both artificial and real-world images, including an astrophysical application, clearly prove the high performance of our methods, as compared to classical algorithms. PMID:19596636

Guidara, Rima; Hosseini, Shahram; Deville, Yannick

2009-11-01

61

INVITED PAPER: Application of blue green and ultraviolet micro-LEDs to biological imaging and detection  

NASA Astrophysics Data System (ADS)

This paper reviews authors' laboratory's work on the development of nitride-based blue-green and ultraviolet microscale LED devices with particular classes of imaging and spectroscopic applications in cellular level biology. Starting from neuroscience, we illustrate the utility of blue-green micro-LEDs for voltage-sensitive dye imaging of individual neural cells, as well as their ultraviolet counterparts for photostimulation of neurons. Arrays of micro-LEDs are also shown to be useful in projecting spatiotemporal patterns of photoexcitation to study the visual system development in living animals. As another illustration of the utility of the emerging nitride microdevice technology, we demonstrate the application of UV micro-LED arrays in bio-sensing technology as the core of a real-time fluorescence spectroscopy biowarning system.

Xu, H.; Zhang, J.; Davitt, K. M.; Song, Y.-K.; Nurmikko, A. V.

2008-05-01

62

Holographic illumination in optical readout focal plane array infrared imaging system.  

PubMed

An IR imaging system based on a microelectromechanical system (MEMS) microcantilever is uncooled, low-cost, and more reliable than traditional systems. However, it is difficult to avoid unwanted shape distortions in fabrication, which can degrade image quality in many ways, so we use holography to compensate for these shape distortions in an optical readout focal plane array (FPA) IR imaging system. The experiment shows that it is a feasible way to improve system performance, especially when it is too difficult to perfect the techniques of an FPA fabrication. PMID:19927206

Liu, Ming; Zhao, Yuejin; Dong, Liquan; Yu, Xiaomei; Liu, Xiaohua; Hui, Mei; You, Jianfeng; Yi, Yuliang

2009-11-15

63

Electric Field Reconstruction in the Image Plane of a High-Contrast Coronagraph Using a Set of Pinholes around the Lyot Plane  

NASA Technical Reports Server (NTRS)

In a setup similar to the self coherent camera, we have added a set of pinholes in the diffraction ring of the Lyot plane in a high-contrast stellar Lyot coronagraph. We describe a novel complex electric field reconstruction from image plane intensity measurements consisting of light in the coronagraph's dark hole interfering with light from the pinholes. The image plane field is modified by letting light through one pinhole at a time. In addition to estimation of the field at the science camera, this method allows for self-calibration of the probes by letting light through the pinholes in various permutations while blocking the main Lyot opening. We present results of estimation and calibration from the High Contrast Imaging Testbed along with a comparison to the pair-wise deformable mirror diversity based estimation technique. Tests are carried out in narrow-band light and over a composite 10% bandpass.

Giveona, Amir; Shaklan, Stuart; Kern, Brian; Noecker, Charley; Kendrick, Steve; Wallace, Kent

2012-01-01

64

Dual-plane stereoscopic particle image velocimetry: system set-up and its application on a lobed jet mixing flow  

E-print Network

Dual-plane stereoscopic particle image velocimetry: system set-up and its application on a lobed and system set-up of a dual- plane stereoscopic particle image velocimetry (PIV) system, which can obtain results were compared with the simultaneous measurement re- sults of a laser Doppler velocimetry (LDV

Hu, Hui

65

AlGaN-Free Blue III-Nitride Laser Diodes Grown on c-Plane GaN Substrates  

NASA Astrophysics Data System (ADS)

We report on the fabrication of InGaN-based multiple-quantum-well laser diodes (LDs) emitting at 420 nm. Structures with standard claddings (p- and n-AlGaN), asymmetric claddings (p-GaN and n-AlGaN), and AlGaN-free claddings were grown by metal organic vapor phase epitaxy on polar c-plane free-standing GaN substrates. Electrical and optical properties of each LD are presented. Thanks to an optimized design of the InGaN waveguide and active region, cw lasing of a completely AlGaN-free laser diode is demonstrated, with a threshold current density <5 kA/cm2 and a differential efficiency per facet of ˜0.4 W/A without high-reflection coatings.

Dorsaz, Julien; Castiglia, Antonino; Cosendey, Gatien; Feltin, Eric; Rossetti, Marco; Duelk, Marcus; Velez, Christian; Carlin, Jean-François; Grandjean, Nicolas

2010-09-01

66

Bit-plane based analysis of integer wavelet coefficients for image compression  

NASA Astrophysics Data System (ADS)

This paper presents bit-plane based statistical study for integer wavelet transforms commonly used in image compression. In each bit-plane, the coefficients were modeled as binary random variables. Experimental results indicate the probability of the significant coefficients (P I), in each bit-plane, monotonically increases from P I ~ 0 at the most significant bits (MSB) to P I~ 0.5 at the least significant bits (LSB). Then, a parameterized model to predict P I from the MSB to the LSB was proposed. Also, the correlation among the different bit-planes within the same coefficient was investigated. In addition, this study showed correlation of the significant coefficients in the same spatial orientation among different subbands. Finally, clustering within the each subband and across the different subband with the same spatial orientation was investigated. Our results show strong correlation of previously coded significant coefficients at higher levels and the significant coefficients in future passes at lower levels. The overall study of this paper is useful in understanding and enhancing existing wavelet-based image compression algorithms such as SPIHT and EBC.

Abu-Hajar, Ahmed

2006-01-01

67

PEGylated Prussian blue nanocubes as a theranostic agent for simultaneous cancer imaging and photothermal therapy.  

PubMed

Theranostic agents with both imaging and therapeutic functions have attracted enormous interests in cancer diagnosis and treatment in recent years. In this work, we develop a novel theranostic agent based on Prussian blue nanocubes (PB NCs), a clinically approved agent with strong near-infrared (NIR) absorbance and intrinsic paramagnetic property, for in vivo bimodal imaging-guided photothermal therapy. After being coated with polyethylene glycol (PEG), the obtained PB-PEG NCs are highly stable in various physiological solutions. In vivo T1-weighted magnetic resonance (MR) and photoacoustic tomography (PAT) bimodal imaging uncover that PB-PEG NCs after intravenous (i.v.) injection show high uptake in the tumor. Utilizing the strong and super stable NIR absorbance of PB, in vivo cancer treatment is then conducted upon i.v. injection of PB-PEG NCs followed by NIR laser irradiation of the tumors, achieving excellent therapeutic efficacy in a mouse tumor model. Comprehensive blood tests and careful histological examinations reveal no apparent toxicity of PB-PEG NCs to mice at our tested dose, which is two-fold of the imaging/therapy dose, within two months. Our work highlights the great promise of Prussian blue with well engineered surface coating as a multifunctional nanoprobe for imaging-guided cancer therapy. PMID:25239041

Cheng, Liang; Gong, Hua; Zhu, Wenwen; Liu, Jingjing; Wang, Xiaoyong; Liu, Gang; Liu, Zhuang

2014-12-01

68

Uncooled bolometer-type Terahertz focal plane array and camera for real-time imaging  

NASA Astrophysics Data System (ADS)

Real-time Terahertz (THz) imaging technologies which make use of uncooled bolometer-type infrared focal plane arrays (FPAs) and quantum cascade lasers (QCLs) will be reviewed. A description of how THz focal plane array and THz imagers have been developed on the basis of infrared technologies, especially the improvement in both THz sensitivity of bolometer-type FPA and THz transmittance of materials for lens and vacuum package window will be given. Characteristics of 320×240 THz-FPA, such as relation of noise equivalent power (NEP) to wavelength and real-time THz imageries will be presented. One of the imageries indicates that THz technology is promising for label-free detection of reaction of small molecules with proteins.

Oda, Naoki

2010-08-01

69

Imaging off-plane shear waves with a two-dimensional phononic crystal lens.  

PubMed

A two-dimensional flat phononic crystal (PC) lens for focusing off-plane shear waves is proposed. The lens consists of a triangular lattice hole-array, embedded in a solid matrix. The self-collimation effect is employed to guide the shear waves propagating through the lens along specific directions. The Dirichlet-to-Neumann maps (DtN) method is employed to calculate the band structure of the PC, which can avoid the problems of bad convergence and fake bands automatically in the void-solid PC structure. When the lens is illuminated by the off-plane shear waves emanating from a point source, a subwavelength image appears in the far-field zone. The imaging characteristics are investigated by calculating the displacement fields explicitly using the multiple scattering method, and the results are in good agreement with the ray-trace predictions. Our results may provide insights for designing new phononic devices. PMID:21386343

Chiang, Chen-Yu; Luan, Pi-Gang

2010-02-10

70

Fast functional imaging of multiple brain regions in intact zebrafish larvae using Selective Plane Illumination Microscopy  

PubMed Central

The optical transparency and the small dimensions of zebrafish at the larval stage make it a vertebrate model of choice for brain-wide in-vivo functional imaging. However, current point-scanning imaging techniques, such as two-photon or confocal microscopy, impose a strong limit on acquisition speed which in turn sets the number of neurons that can be simultaneously recorded. At 5 Hz, this number is of the order of one thousand, i.e., approximately 1–2% of the brain. Here we demonstrate that this limitation can be greatly overcome by using Selective-plane Illumination Microscopy (SPIM). Zebrafish larvae expressing the genetically encoded calcium indicator GCaMP3 were illuminated with a scanned laser sheet and imaged with a camera whose optical axis was oriented orthogonally to the illumination plane. This optical sectioning approach was shown to permit functional imaging of a very large fraction of the brain volume of 5–9-day-old larvae with single- or near single-cell resolution. The spontaneous activity of up to 5,000 neurons was recorded at 20 Hz for 20–60 min. By rapidly scanning the specimen in the axial direction, the activity of 25,000 individual neurons from 5 different z-planes (approximately 30% of the entire brain) could be simultaneously monitored at 4 Hz. Compared to point-scanning techniques, this imaging strategy thus yields a ?20-fold increase in data throughput (number of recorded neurons times acquisition rate) without compromising the signal-to-noise ratio (SNR). The extended field of view offered by the SPIM method allowed us to directly identify large scale ensembles of neurons, spanning several brain regions, that displayed correlated activity and were thus likely to participate in common neural processes. The benefits and limitations of SPIM for functional imaging in zebrafish as well as future developments are briefly discussed. PMID:23576959

Panier, Thomas; Romano, Sebastian A.; Olive, Raphael; Pietri, Thomas; Sumbre, German; Candelier, Raphael; Debregeas, Georges

2013-01-01

71

Photo-acoustic imaging of blue nanoparticle targeted brain tumor for intra-operative glioma delineation  

NASA Astrophysics Data System (ADS)

Distinguishing the tumor from the background neo-plastic tissue is challenging for cancer surgery such as surgical resection of glioma. Attempts have been made to use visible or fluorescent markers to delineate the tumors during surgery. However, the systemic injection of the dyes requires high dose, resulting in negative side effects. A novel method to delineate rat brain tumors intra-operatively, as well as post-operatively, using a highly sensitive photoacoustic imaging technique enhanced by tumor targeting blue nanoparticle as contrast agent is demonstrated. The nanoparticles are made of polyacrylamide (PAA) matrix with covalently linked Coomassie-Blue dye. They contain 7.0% dye and the average size is 80nm. Their surface was conjugated with F3 peptide for active tumor targeting. These nanoparticles are nontoxic, chemically inert and have long plasma circulation lifetime, making them suitable as nanodevices for imaging using photoacoustics. Experiments on phantoms and rat brains tumors ex-vivo demonstrate the high sensitivity of photoacoustic imaging in delineating the tumor, containing contrast agent at concentrations too low to be visualized by eye. The control tumors without nanoparticles did not show any enhanced signal. This study shows that photoacoustic imaging facilitated with the nanoparticle contrast agent could contribute to future surgical procedures for glioma.

Ray, Aniruddha; Wang, Xueding; Koo Lee, Yong-Eun; Hah, HoeJin; Kim, Gwangseong; Chen, Thomas; Orrienger, Daniel; Sagher, Oren; Kopelman, Raoul

2011-07-01

72

Multispectral Thermal Imager Optical Assembly Performance and Intergration of the Flight Focal Plane Assembly  

SciTech Connect

The Multispectral Thermal Imager Optical Assembly (OA) has been fabricated, assembled, successfully performance tested, and integrated into the flight payload structure with the flight Focal Plane Assembly (FPA) integrated and aligned to it. This represents a major milestone achieved towards completion of this earth observing E-O imaging sensor that is to be operated in low earth orbit. The OA consists of an off-axis three mirror anastigmatic (TMA) telescope with a 36 cm unobscured clear aperture, a wide-field-of-view (WFOV) of 1.82° along the direction of spacecraft motion and 1.38° across the direction of spacecraft motion. It also contains a comprehensive on-board radiometric calibration system. The OA is part of a multispectral pushbroom imaging sensor which employs a single mechanically cooled focal plane with 15 spectral bands covering a wavelength range from 0.45 to 10.7 µm. The OA achieves near diffraction-limited performance from visible to the long-wave infrared (LWIR) wavelengths. The two major design drivers for the OA are 80% enpixeled energy in the visible bands and radiometric stability. Enpixeled energy in the visible bands also drove the alignment of the FPA detectors to the OA image plane to a requirement of less than ± 20 µm over the entire visible detector field of view (FOV). Radiometric stability requirements mandated a cold Lyot stop for stray light rejection and thermal background reduction. The Lyot stop is part of the FPA assembly and acts as the aperture stop for the imaging system. The alignment of the Lyot stop to the OA drove the centering and to some extent the tilt alignment requirements of the FPA to the OA.

Blake, Dick; Byrd, Don; Christensen, Wynn; Henson, Tammy; Krumel, Les; Rappoport, William; Shen, Gon-Yen

1999-06-08

73

Magnetic resonance imaging planes for the 3-dimensional characterisation of human coronary arteries.  

PubMed Central

We report a magnetic resonance imaging study which developed a consistent hierarchy of imaging planes for examination of the origins, courses and principal branches of the main coronary arteries of prepared human cadaveric hearts. The reference longitudinal axis was chosen between the aortic valve and the apex of the left ventricle. A series of transverse planes then successfully visualised the ostia of the left and right coronary arteries; the left main coronary, its bifurcation, and the left anterior descending artery for a distance 24 mm distal to its origin were clearly distinct in successively posterior sections as was the emergence and course of the right coronary artery. Further sections were derived from an axis that joined the posterior aspects of the left and right coronary artery ostia seen in cross-section, which demonstrated the origins of these arteries. They also traced the circumflex artery 30 mm beyond its point of emergence and demonstrated the course of the right coronary artery between the right ventricle and right atrium. The anatomical identifications were confirmed in selective 3-dimensional reconstructions of the cardiac anatomy around the aortic root and pulmonary artery origin. The orthogonal anatomical arrangements of the left and right coronary artery arterial trees thus permit a consistent set of imaging planes useful for the visualisation of all the major branches in a static heart in vitro. This may offer an approach useful for clinical imaging of human coronary vessels in vivo in the moving heart. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:7961140

Gates, A R; Huang, C L; Crowley, J J; Gresham, A; Shapiro, L M; Carpenter, T A; Hall, L D

1994-01-01

74

Midsagittal plane extraction from brain images based on 3D SIFT  

NASA Astrophysics Data System (ADS)

Midsagittal plane (MSP) extraction from 3D brain images is considered as a promising technique for human brain symmetry analysis. In this paper, we present a fast and robust MSP extraction method based on 3D scale-invariant feature transform (SIFT). Unlike the existing brain MSP extraction methods, which mainly rely on the gray similarity, 3D edge registration or parameterized surface matching to determine the fissure plane, our proposed method is based on distinctive 3D SIFT features, in which the fissure plane is determined by parallel 3D SIFT matching and iterative least-median of squares plane regression. By considering the relative scales, orientations and flipped descriptors between two 3D SIFT features, we propose a novel metric to measure the symmetry magnitude for 3D SIFT features. By clustering and indexing the extracted SIFT features using a k-dimensional tree (KD-tree) implemented on graphics processing units, we can match multiple pairs of 3D SIFT features in parallel and solve the optimal MSP on-the-fly. The proposed method is evaluated by synthetic and in vivo datasets, of normal and pathological cases, and validated by comparisons with the state-of-the-art methods. Experimental results demonstrated that our method has achieved a real-time performance with better accuracy yielding an average yaw angle error below 0.91° and an average roll angle error no more than 0.89°.

Wu, Huisi; Wang, Defeng; Shi, Lin; Wen, Zhenkun; Ming, Zhong

2014-03-01

75

Midsagittal plane extraction from brain images based on 3D SIFT.  

PubMed

Midsagittal plane (MSP) extraction from 3D brain images is considered as a promising technique for human brain symmetry analysis. In this paper, we present a fast and robust MSP extraction method based on 3D scale-invariant feature transform (SIFT). Unlike the existing brain MSP extraction methods, which mainly rely on the gray similarity, 3D edge registration or parameterized surface matching to determine the fissure plane, our proposed method is based on distinctive 3D SIFT features, in which the fissure plane is determined by parallel 3D SIFT matching and iterative least-median of squares plane regression. By considering the relative scales, orientations and flipped descriptors between two 3D SIFT features, we propose a novel metric to measure the symmetry magnitude for 3D SIFT features. By clustering and indexing the extracted SIFT features using a k-dimensional tree (KD-tree) implemented on graphics processing units, we can match multiple pairs of 3D SIFT features in parallel and solve the optimal MSP on-the-fly. The proposed method is evaluated by synthetic and in vivo datasets, of normal and pathological cases, and validated by comparisons with the state-of-the-art methods. Experimental results demonstrated that our method has achieved a real-time performance with better accuracy yielding an average yaw angle error below 0.91° and an average roll angle error no more than 0.89°. PMID:24583964

Wu, Huisi; Wang, Defeng; Shi, Lin; Wen, Zhenkun; Ming, Zhong

2014-03-21

76

Suspended Blue  

Microsoft Academic Search

Driving in the deep plains, surrounded by a boundless plane of land and a sky that demands awe, I am aware of a profound feeling of endlessness. At the transitional moments between day and night, when the sky is filled with such a deep, bright blue that all of the air appears saturated with it, and the uninterrupted horizon turns

Rose Heydt

2012-01-01

77

Detection of cracks under cladding using magneto-optic imaging and rotating in-plane magnetization  

NASA Astrophysics Data System (ADS)

Conventional nondestructive inspection (NDI) of steel components, using magnetic particle, flux-leakage or near surface ultrasonic methods, is rendered difficult by the presence of protective coatings such as paint or stainless- steel cladding. Thick-section nuclear reactor pressure vessels (RPVs), having as-welded cladding up to 0.25 inches thick are a case in point. Here, magnetic particle techniques do not work and ultrasonic techniques are difficult to apply because of cladding roughens and variable elastic properties in the cladding and the weld interface. An NDI technique that is essentially unaffected by standard thicknesses of protective coatings would be a major advance. Magneto-optic imaging is one such technique. While conventional magneto-optic/eddy current imagers (MOIs) are a proven technology in the NDI of nonferromagnetic conductors, they do not possess a self-contained method for magnetizing steel. The purpose of this work was to develop methods for producing rotating, in-plane magnetization and then combine this technology with magneto-optic imaging to produce a self-contained instrument capable of real-time imaging of cracks in steel through protective coatings. We successfully demonstrated rotating in-plane magnetization using special 'quadrature' magnetic-yokes designed to accommodate both flat and cylindrical steel surfaces. The yokes were attached one at a time, to an MOI of reduced size, and the combined system was placed on a sample of the appropriate curvature containing cracks. A two-channel power amplifier was used to drive the yoke coils in quadrature. The resulting crack images were found to be much less sensitive to liftoff than conventional magnetic particle or flux-leakage NDI. In particular, cracks in steel were successfully imaged through 0.125 inches of stainless-steel cladding, making it likely that images of cracks in steel under even thicker cladding should be possible after further development of the technology. Unlike conventional magnetic particle or flux- leakage NDI, where crack orientation is important, rotating in-plane magnetization renders crack orientation irrelevant. Finally, because of these successes, the new NDI technology for steel should find many important applications.

Fitzpatrick, Gerald L.; Skaugset, Richard L.; Thome, David K.; Shih, William C.

1996-11-01

78

Camera model and calibration process for high-accuracy digital image metrology of inspection planes  

NASA Astrophysics Data System (ADS)

High accuracy digital image based metrology must rely on an integrated model of image generation that is able to consider simultaneously the geometry of the camera vs. object positioning, and the conversion of the optical image on the sensor into an electronic digital format. In applications of automated visual inspection involving the analysis of approximately plane objects these models are generally simplified in order to facilitate the process of camera calibration. In this context, the lack of rigor in the determination of the intrinsic parameters in such models is particularly relevant. Aiming at the high accuracy metrology of contours of objects lying on an analysis plane, and involving sub-pixel measurements, this paper presents a three-stage camera model that includes an extrinsic component of perspective distortion and the intrinsic components of radial lens distortion and sensor misalignment. The later two factors are crucial in applications of machine vision that rely on the use of low cost optical components. A polynomial model for the negative radial lens distortion of wide field of view CCTV lenses is also established.

Correia, Bento A. B.; Dinis, Joao

1998-10-01

79

Diffusion tensor imaging and T2 relaxometry of bilateral lumbar nerve roots: feasibility of in-plane imaging  

PubMed Central

Lower back pain is a common problem frequently encountered without specific biomarkers that correlate well with an individual patient's pain generators. MRI quantification of diffusion and T2 relaxation properties may provide novel insight into mechanical and inflammatory changes that occur in lumbosacral nerve roots in patients with lower back pain. Imaging the spinal nerve roots accurately is difficult due to their small caliber and oblique course in all three planes. Two-dimensional in-plane imaging of the lumbosacral nerve roots requires oblique coronal imaging with large field-of-view (FOV) in both dimensions, resulting in severe geometric distortions using single-shot echo planar imaging (EPI) techniques. The present work describes initial success using a reduced-FOV single-shot spin-echo EPI acquisition to obtain in-plane DTI and T2 mapping of the bilateral lumbar nerve roots at the L4 level of healthy subjects, minimizing partial volume effects, breathing artifacts and geometric distortions. A significant variation of DTI and T2 mapping metrics is also reported along the course of the normal nerve root. The FA value is statistically significantly lower in the dorsal root ganglia (0.287 ± 0.068) than in regions more distally in the spinal nerve (0.402 ± 0.040) (p<10?5). The T2 relaxation value is statistically significantly higher in the dorsal root ganglia (78.0 ± 11.9 ms) than in regions more distally in the spinal nerve (59.5 ± 7.4 ms) (p<10?5). Quantification of nerve root DTI and T2 properties using the proposed methodology may identify the specific site of any degenerative and inflammatory changes along the nerve roots of patients with lower back pain. PMID:23208676

Karampinos, Dimitrios C.; Melkus, Gerd; Shepherd, Timothy M.; Banerjee, Suchandrima; Saritas, Emine U.; Shankaranarayanan, Ajit; Hess, Christopher P.; Link, Thomas M.; Dillon, William P.; Majumdar, Sharmila

2013-01-01

80

Clockwork blue: on the evolution of non-image-forming retinal photoreceptors in marine and terrestrial vertebrates  

Microsoft Academic Search

This paper presents a hypothesis that could explain why blue light appears to dominate non-image-forming (NIF) ocular photoreception\\u000a in marine as well as terrestrial vertebrates. Indeed, there is more and more evidence suggesting that ‘novel’ retinal photoreceptors,\\u000a which are sensitive to blue light and were only discovered in the 1990s, could be a feature shared by all vertebrates. In\\u000a our

T. C. Erren; M. Erren; A. Lerchl; V. B. Meyer-Rochow

2008-01-01

81

Sentinel lymph nodes fluorescence detection and imaging using Patent Blue V bound to human serum albumin  

PubMed Central

Patent Blue V (PBV), a dye used clinically for sentinel lymph node detection, was mixed with human serum albumin (HSA). After binding to HSA, the fluorescence quantum yield increased from 5 × 10?4 to 1.7 × 10?2, which was enough to allow fluorescence detection and imaging of its distribution. A detection threshold, evaluated in scattering test objects, lower than 2.5 nmol × L?1 was obtained, using a single-probe setup with a 5-mW incident light power. The detection sensitivity using a fluorescence imaging device was in the µmol × L?1 range, with a noncooled CCD camera. Preclinical evaluation was performed on a rat model and permitted to observe inflamed nodes on all animals. PMID:23024922

Tellier, Franklin; Steibel, Jerome; Chabrier, Renee; Ble, Francois Xavier; Tubaldo, Herve; Rasata, Ravelo; Chambron, Jacques; Duportail, Guy; Simon, Herve; Rodier, Jean-Francois; Poulet, Patrick

2012-01-01

82

Semiconductor detectors and focal plane arrays for far-infrared imaging  

NASA Astrophysics Data System (ADS)

The detection of far-infrared (far-IR) and sub-mm-wave radiation is resistant to the commonly employed techniques in the neighbouring microwave and IR frequency bands. In this wavelength detection range the use of solid state detectors has been hampered for the reasons of transit time of charge carriers being larger than the time of one oscillation period of radiation. Also the energy of radiation quanta is substantially smaller than the thermal energy at room temperature and even liquid nitrogen temperature. The realization of terahertz (THz) emitters and receivers is a challenge because the frequencies are too high for conventional electronics and the photon energies are too small for classical optics. Development of semiconductor focal plane arrays started in seventies last century and has revolutionized imaging systems in the next decades. This paper presents progress in far-IR and sub-mm-wave semiconductor detector technology of focal plane arrays during the past twenty years. Special attention is given on recent progress in the detector technologies for real-time uncooled THz focal plane arrays such as Schottky barrier arrays, field-effect transistor detectors, and microbolometers. Also cryogenically cooled silicon and germanium extrinsic photoconductor arrays, and semiconductor bolometer arrays are considered.

Rogalski, A.

2013-12-01

83

Detection of moving objects in image plane for robot navigation using monocular vision  

NASA Astrophysics Data System (ADS)

This article presents an algorithm for moving object detection (MOD) in robot visual simultaneous localization and mapping (SLAM). This MOD algorithm is designed based on the defining epipolar constraint for the corresponding feature points on image plane. An essential matrix obtained using the state estimator is utilized to represent the epipolar constraint. Meanwhile, the method of speeded-up robust feature (SURF) is employed in the algorithm to provide a robust detection for image features as well as a better description of landmarks and of moving objects in visual SLAM system. Experiments are carried out on a hand-held monocular camera to verify the performances of the proposed algorithm. The results show that the integration of MOD and SURF is efficient for robot navigating in dynamic environments.

Wang, Yin-Tien; Sun, Chung-Hsun; Chiou, Ming-Jang

2012-12-01

84

Use of Fluorescence Imaging in Combination with Patent Blue Dye versus Patent Blue Dye Alone in Sentinel Lymph Node Biopsy in Breast Cancer  

PubMed Central

Purpose Near-infrared fluorescence imaging with indocyanine green (ICG) has the potential to improve sentinel lymph node (SLN) mapping in breast cancer. In this clinical trial, we compared the potential value of ICG combined with blue dye with that of blue dye alone for detecting SLNs. Methods Patients undergoing SLN biopsy (SLNB) between November 2010 and November 2013 were included. Up to December 2011, SLNs were detected by using patent blue (PB) alone, and since January 2012, by using PB in combination with ICG. The patients were divided into the following two groups: group A (ICG-PB; n=96) and group B (PB; n=73), and SLN detection parameters were compared between the groups. All patients underwent level I and II axillary dissections after SLNB. Results In group A, the SLN detection rate was 96.9% (93/96), the accuracy of detection was 98.9% (92/93), and the false-negative rate (FNR) was 3.4% (1/29). In group B, the SLN detection rate was 84.9% (62/73), the accuracy of detection was 96.8% (60/62), and the FNR was 11.1% (2/18). The ICG-PB group showed significantly superior results compared to the PB group for SLN detection (p=0.005) and a greatly improved FNR. Conclusion The combined fluorescence and blue dye-based tracer technique was superior to the use of blue dye alone for identifying SLNs, and for predicting axillary lymph node status in patients with breast cancer; in addition, the combined technique had reduced false-negative results. PMID:25320623

Tong, Meng; Gao, Wei

2014-01-01

85

Vibration measurement of a miniature component by high-speed image-plane digital holographic microscopy  

SciTech Connect

Measuring deformation of vibrating specimens whose dimensions are in the submillimeter range introduces a number of difficulties using laser interferometry. Normal interferometry is not suitable because of a phase ambiguity problem. In addition, the noise effect is much more serious in the measurement of small objects because a high-magnification lens is used. We present a method for full-field measurement of displacement, velocity, and acceleration of a vibrating miniature object based on image-plane digital holographic microscopy. A miniature cantilever beam is excited by a piezoelectric transducer stage with a sinusoidal configuration. A sequence of digital holograms is captured using a high-speed digital holographic microscope. Windowed Fourier analysis is applied in the spatial and spatiotemporal domains to extract the displacement, velocity and acceleration. The result shows that a combination of image-plane digital holographic microscopy and windowed Fourier analyses can be used to study vibration without encountering a phase ambiguity problem, and one can obtain instantaneous kinematic parameters on each point.

Fu Yu; Shi Hongjian; Miao Hong

2009-04-10

86

Solid-state image sensor with focal-plane digital photon-counting pixel array  

NASA Technical Reports Server (NTRS)

A photosensitive layer such as a-Si for a UV/visible wavelength band is provided for low light level imaging with at least a separate CMOS amplifier directly connected to each PIN photodetector diode to provide a focal-plane array of NxN pixels, and preferably a separate photon-counting CMOS circuit directly connected to each CMOS amplifier, although one row of counters may be time shared for reading out the photon flux rate of each diode in the array, together with a buffer memory for storing all rows of the NxN image frame before transfer to suitable storage. All CMOS circuitry is preferably fabricated in the same silicon layer as the PIN photodetector diode for a monolithic structure, but when the wavelength band of interest requires photosensitive material different from silicon, the focal-plane array may be fabricated separately on a different semiconductor layer bump-bonded or otherwise bonded for a virtually monolithic structure with one free terminal of each diode directly connected to the input terminal of its CMOS amplifier and digital counter for integration of the photon flux rate at each photodetector of the array.

Fossum, Eric R. (inventor); Pain, Bedabrata (inventor)

1995-01-01

87

Prefractal scaling of apparent soil moisture estimated from vertical planes of Vertisol pit images  

NASA Astrophysics Data System (ADS)

Image analysis could be a useful tool for investigating the spatial patterns of apparent soil moisture at multiple resolutions. The objectives of the present work were (i) to define apparent soil moisture patterns from vertical planes of Vertisol pit images and (ii) to describe the scaling of apparent soil moisture distribution using fractal parameters. Twelve soil pits (0.70 m long x 0.60 m width x 0.30 m depth) were excavated on a bare Mazic Pellic Vertisol. Six of them were excavated in April/2011 and six pits were established in May/2011 after three days of a moderate rainfall event. Digital photographs were taken from each Vertisol pit using a KodakTM digital camera. The mean image size was 1600 x 945 pixels with one physical pixel ? 373 ?m of the photographed soil pit. Each soil image was analyzed using two prefractal scaling exponents, box counting (capacity) dimension (DBC) and interface fractal dimension (Di), and three prefractal scaling coefficients, the total number of boxes intercepting the foreground pattern at a unit scale (A), fractal lacunarity at the unit scale (?1) and Shannon entropy at the unit scale (S1). All prefractal scaling parameters identified significant differences between both sets of spatial patterns. Fractal lacunarity was the best discriminator between apparent soil moisture patterns. Soil image interpretation with prefractal parameters can be incorporated within site-specific agriculture toolbox. While fractal exponents condense information on space filling characteristics of the pattern, prefractal coefficients represent the investigated soil property as seen through a higher resolution microscope. In spite of some computational and practical limitations, image analysis of apparent soil moisture patterns could be used in connection with traditional soil moisture sampling, which always renders punctual estimates. Key words: Image analysis, fractal scaling, apparent soil moisture, Vertisols Acknowledgements This work has been partially funded by project AGL2010-21501/AGR (MICINN)

Cumbrera, R.; Tarquis, A. M.; Gascó, G.; Millán, H.

2012-04-01

88

Automatic standard plane adjustment on mobile C-Arm CT images of the calcaneus using atlas-based feature registration  

NASA Astrophysics Data System (ADS)

Intraarticular fractures of the calcaneus are routinely treated by open reduction and internal fixation followed by intraoperative imaging to validate the repositioning of bone fragments. C-Arm CT offers surgeons the possibility to directly verify the alignment of the fracture parts in 3D. Although the device provides more mobility, there is no sufficient information about the device-to-patient orientation for standard plane reconstruction. Hence, physicians have to manually align the image planes in a position that intersects with the articular surfaces. This can be a time-consuming step and imprecise adjustments lead to diagnostic errors. We address this issue by introducing novel semi-/automatic methods for adjustment of the standard planes on mobile C-Arm CT images. With the semi-automatic method, physicians can quickly adjust the planes by setting six points based on anatomical landmarks. The automatic method reconstructs the standard planes in two steps, first SURF keypoints (2D and newly introduced pseudo-3D) are generated for each image slice; secondly, these features are registered to an atlas point set and the parameters of the image planes are transformed accordingly. The accuracy of our method was evaluated on 51 mobile C-Arm CT images from clinical routine with manually adjusted standard planes by three physicians of different expertise. The average time of the experts (46s) deviated from the intermediate user (55s) by 9 seconds. By applying 2D SURF key points 88% of the articular surfaces were intersected correctly by the transformed standard planes with a calculation time of 10 seconds. The pseudo-3D features performed even better with 91% and 8 seconds.

Brehler, Michael; Görres, Joseph; Wolf, Ivo; Franke, Jochen; von Recum, Jan; Grützner, Paul A.; Meinzer, Hans-Peter; Nabers, Diana

2014-03-01

89

Simultaneous quantification of flow and tissue velocities based on multi-angle plane wave imaging.  

PubMed

A quantitative angle-independent 2-D modality for flow and tissue imaging based on multi-angle plane wave acquisition was evaluated. Simulations of realistic flow in a carotid artery bifurcation were used to assess the accuracy of the vector Doppler (VD) technique. Reduction in root mean square deviation from 27 cm/s to 6 cm/s and 7 cm/s to 2 cm/s was found for the lateral (vx) and axial (vz) velocity components, respectively, when the ensemble size was increased from 8 to 50. Simulations of a Couette flow phantom (vmax = 2.7 cm/s) gave promising results for imaging of slowly moving tissue, with root mean square deviation of 4.4 mm/s and 1.6 mm/s for the x- and z-components, respectively. A packet acquisition scheme providing both B-mode and vector Doppler RF data was implemented on a research scanner, and beamforming and further post-processing was done offline. In vivo results of healthy volunteers were in accordance with simulations and gave promising results for flow and tissue vector velocity imaging. The technique was also tested in patients with carotid artery disease. Using the high ensemble vector Doppler technique, blood flow through stenoses and secondary flow patterns were better visualized than in ordinary color Doppler. Additionally, the full velocity spectrum could be obtained retrospectively for arbitrary points in the image. PMID:23549533

Ekroll, Ingvild Kinn; Swillens, Abigail; Segers, Patrick; Dahl, Torbjørn; Torp, Hans; Lovstakken, Lasse

2013-04-01

90

An image-plane algorithm for JWST's non-redundant aperture mask data  

E-print Network

The high angular resolution technique of non-redundant masking (NRM) or aperture masking interferometry (AMI) has yielded images of faint protoplanetary companions of nearby stars from the ground. AMI on James Webb Space Telescope (JWST)'s Near Infrared Imager and Slitless Spectrograph (NIRISS) has a lower thermal background than ground-based facilites and does not suffer from atmospheric instability. NIRISS AMI images are likely to have 90 - 95% Strehl ratio between 2.77 and 4.8 micron. In this paper we quantify factors that limit the raw point source contrast of JWST NRM. We develop an analytic model of the NRM point spread function which includes different optical path delays (pistons) between mask holes and fit the model parameters with image plane data. It enables a straightforward way to exclude bad pixels, is suited to limited fields of view, and can incorporate effects such as intra-pixel sensitivity variations. We simulate various sources of noise to estimate their effect on the standard deviation of...

Greenbaum, Alexandra Z; Sivaramakrishnan, Anand; Lacour, Sylvestre

2014-01-01

91

Determination of intracranial tumor volumes in a rodent brain using magnetic resonance imaging, Evans blue, and histology: a comparative study.  

PubMed

The measurement of tumor volumes is a practical and objective method of assessing the efficacy of a therapeutic agent. However, the relative accuracy of different methods of assessing tumor volume has been unclear. Using T1-weighted, gadolinium-enhanced magnetic resonance Imaging (T1-MRI), Evans Blue infusion and histology we measured intracranial tumor volumes in a rodent brain tumor model (RT2) at days 10, 16 and 18 after implantation of cells in the caudate putamen. There is a good correlation between tumor volumes comparing T1-MRI and Evans Blue (r2 = 0.99), T1-MRI and Histology (r2 = 0.98) and histology and Evans Blue (r2 = 0.93). Each of these methods is reliable in estimating tumor volumes in laboratory animals. There was significant uptake of gadolinium and Evans Blue in the tumor suggesting a wide disruption of the blood-brain barrier. PMID:10721633

Prabhu, S S; Broaddus, W C; Oveissi, C; Berr, S S; Gillies, G T

2000-02-01

92

Forensic discrimination of blue ballpoint pen inks based on thin layer chromatography and image analysis.  

PubMed

This article aims to provide a new and fast method for differentiation of inks on a questioned document. The data acquisition was carried out by designing specific image analysis software for evaluating thin layer chromatograms (TLC-IA). The ink spot was extracted from the document using methanol and separated by TLC using plastic sheet silica gel 60 without fluorescent indicator, and a mixture of ethyl acetate, ethanol, and water (70:35:30, v/v/v) as mobile phase. To discriminate between different pen inks, new software was designed on the basis of intensity profile of red, green, and blue (RGB) characteristic. In practice, after development of chromatogram, the chromatograms were scanned by ordinary office scanner, intensity profiles of RGB characteristics on the development straight of each sample were produced and compared with the mentioned software. RGB profiles of ballpoint inks from various manufacturers showed that the patterns in most cases were distinctly different from each other. This new method allowed discriminating among different pen inks with a high reliability and the discriminating power of 92.8%. Blue ballpoint pen inks of 41 different samples available on the local market were successfully analyzed and discriminated. PMID:18639403

Djozan, Djavanshir; Baheri, Tahmineh; Karimian, Ghader; Shahidi, Masomeh

2008-08-01

93

Fractal scaling of apparent soil moisture estimated from vertical planes of Vertisol pit images  

NASA Astrophysics Data System (ADS)

SummaryImage analysis could be a useful tool for investigating the spatial patterns of apparent soil moisture at multiple resolutions. The objectives of the present work were (i) to define apparent soil moisture patterns from vertical planes of Vertisol pit images and (ii) to describe the scaling of apparent soil moisture distribution using fractal parameters. Twelve soil pits (0.70 m long × 0.60 m width × 0.30 m depth) were excavated on a bare Mazic Pellic Vertisol. Six of them were excavated in April/2011 and six pits were established in May/2011 after 3 days of a moderate rainfall event. Digital photographs were taken from each Vertisol pit using a Kodak™ digital camera. The mean image size was 1600 × 945 pixels with one physical pixel ?373 ?m of the photographed soil pit. Each soil image was analyzed using two fractal scaling exponents, box counting (capacity) dimension (DBC) and interface fractal dimension (Di), and three prefractal scaling coefficients, the total number of boxes intercepting the foreground pattern at a unit scale (A), fractal lacunarity at the unit scale (?1) and Shannon entropy at the unit scale (S1). All the scaling parameters identified significant differences between both sets of spatial patterns. Fractal lacunarity was the best discriminator between apparent soil moisture patterns. Soil image interpretation with fractal exponents and prefractal coefficients can be incorporated within a site-specific agriculture toolbox. While fractal exponents convey information on space filling characteristics of the pattern, prefractal coefficients represent the investigated soil property as seen through a higher resolution microscope. In spite of some computational and practical limitations, image analysis of apparent soil moisture patterns could be used in connection with traditional soil moisture sampling, which always renders punctual estimates.

Cumbrera, Ramiro; Tarquis, Ana M.; Gascó, Gabriel; Millán, Humberto

2012-07-01

94

Detecting Planes In An Uncalibrated Image Pair Manolis I.A. Lourakis, Antonis A. Argyros and Stelios C. Orphanoudakis  

E-print Network

initial estimate, Fornland and Schn¨orr [5] propose a two-step method for locating the dominant plane1 two images. Using a set of point and line features that have been matched between images, the method voting scheme for identifying coplanar subsets of the employed feature set. The method does not require

Argyros, Antonis

95

Highly sensitive detection of the soft tissues based on refraction contrast by in-plane diffraction-enhanced imaging CT  

NASA Astrophysics Data System (ADS)

We discuss the recently proposed computed tomography (CT) technique based on refractive effects for biomedical use, which reconstructs the in-plane refractive-index gradient vector field in a cross-sectional plane of interest by detecting the angular deviation of the beam, refracted by a sample, from the incident beam, using the diffraction-enhanced imaging (DEI) method. The CT has advantages for delineating biological weakly absorbing soft tissues over the conventional absorption-contrast CT because of the use of phase sensitive detection. The paper aims to define the imaging scheme rigidly and to demonstrate its efficacy for non-destructive measurement of biomedical soft-tissue samples without imaging agent. We first describe the imaging principle of in-plane DEI-CT from the physico-mathematical viewpoints in detail, and investigate what physical quantities are extracted from the reconstructed images. Then, we introduce the imaging system using the synchrotron radiation as a light source, constructed at beamline BL-14B in KEK, Japan. Finally, we demonstrate the advantage of the refraction-based image for non-destructive analysis of biological sample by investigating the image of human breast cancer tumors obtained using the imaging system. Here, the refraction- and the apparent absorption-based images obtained simultaneously by the in-plane DEI-CT are compared. Also, the conventional absorption-based image obtained using micro-computed tomography (?CT) imaging system is compared with them. Thereby, it is shown that the refraction contrast much more sensitively delineates the soft tissues than the absorption contrast. In addition, the radiologic-histologic correlation study not only validates the efficacy for imaging soft tissues, but also produces the potential that the pathological inspection for the breast cancer tumors may be feasible non-destructively.

Yuasa, Tetsuya; Hashimoto, Eiko; Maksimenko, Anton; Sugiyama, Hiroshi; Arai, Yoshinori; Shimao, Daisuke; Ichihara, Shu; Ando, Masami

2008-07-01

96

LOOKING THROUGH THE GALACTIC PLANE: IMAGING COLD DUST TOWARD l = 44 DEG  

SciTech Connect

We present imaging observations of continuum emission from interstellar dust at 850 and 1200 {mu}m of a section of the Galactic Plane covering 2 deg{sup 2} centered at l = 44 DEG. Complementary jiggle-mapping and fast-scanning techniques were used, respectively, at these two wavelengths. The mapped area includes the well-known star formation regions W49 and G45.1/45.5. Using an automated clump-finding routine, we identify 132 compact 850 {mu}m emission features within the region above a completeness level of about 200 mJy beam{sup -1}. The positions of the latter objects were used to determine fluxes from the 1200 {mu}m image. Spectral line data were subsequently obtained with the same observing beamwidth as at 850 {mu}m for almost half of the objects; these were either imaged in the {sup 13}CO (3-2) line, or basic characteristics determined using the {sup 12}CO (3-2) transition. We use these data, supplemented by existing {sup 13}CO (1-0) and H I survey data, to determine distances and hence derive masses for the dust clump ensemble, assuming a uniform dust temperature of 15 K. From these data we find that the number-mass relationship for clumps in the field is similar to that found for individual star-forming regions.

Matthews, Henry; Kirk, Helen; Johnstone, Doug [National Research Council Canada, Herzberg Institute of Astrophysics, 5071 West Saanich Rd, Victoria, BC, V9E 2E7 (Canada); Weferling, Bernd [University of Hannover, IDMP, Welfengarten 1, 30167 Hannover (Germany); Cohen, Martin [Radio Astronomy Laboratory, University of California at Berkeley, CA 94720 (United States); Jenness, Tim; Davis, Gary [Joint Astronomy Centre, Hilo, HI 96720 (United States); Evans, Aneurin [School of Physical and Geographical Sciences, Keele University (United Kingdom); Dent, William R. F. [Atacama Large Millimeter Array (Chile); Fuller, Gary [University of Manchester, School of Physics and Astronomy Manchester, M60 1QD (United Kingdom); Jackson, James M.; Rathborne, Jill [Department Astronomy, Boston University, MA 02215 (United States); Richer, John [Mullard Radio Astronomy Obs., Cavendish Laboratory Street, Cambridge CB3 0HE (United Kingdom); Simon, Robert [Physikalisches Institut, Universitaet zu Koeln (Germany)], E-mail: henry.matthews@nrc-cnrc.gc.ca

2009-11-15

97

Measuring soft tissue elasticity by monitoring surface acoustic waves using image plane digital holography  

NASA Astrophysics Data System (ADS)

The detection of tumors in soft tissues, such as breast cancer, is important to achieve at the earliest stages of the disease to improve patient outcome. Tumors often exhibit a greater elastic modulus compared to normal tissues. In this paper, we report our first study to measure elastic properties of soft tissues by mapping the surface acoustic waves (SAWs) with image plane digital holography. The experimental results show that the SAW velocity is proportional to the square root of elastic modulus over a range from 3.7-122kPa in homogeneous tissue phantoms, consistent with Rayleigh wave theory. This technique also permits detection of the interface of two-layer phantoms 10mm deep under surface and the interface depth by quantifying the SAW dispersion.

Li, Shiguang; Oldenburg, Amy L.

2011-03-01

98

EMBRYO DEVELOPMENT AND MORPHOMETRY IN THE BLUE KING CRAB PARALITHODES PLATYPUS STUDIED BY USING IMAGE AND CLUSTER ANALYSIS  

Microsoft Academic Search

In this paper the embryonic development of laboratory-reared blue king crab, Paralithodes platypus, from the Pribilof Islands in the eastern Bering Sea is described. Developing embryos were removed from a female crab at various intervals, digitally photographed under a compound microscope and analyzed using Image-Pro Plus. Nine morphometric parameters were used, including seven measurements (total area, yolk area, embryo length

BRADLEY G. STEVENS

2006-01-01

99

Impact of biplane versus single-plane imaging on radiation dose, contrast load and procedural time in coronary angioplasty  

PubMed Central

Coronary angioplasties can be performed with either single-plane or biplane imaging techniques. The aim of this study was to determine whether biplane imaging, in comparison to single-plane imaging, reduces radiation dose and contrast load and shortens procedural time during (i) primary and elective coronary angioplasty procedures, (ii) angioplasty to the main vascular territories and (iii) procedures performed by operators with various levels of experience. This prospective observational study included a total of 504 primary and elective single-vessel coronary angioplasty procedures utilising either biplane or single-plane imaging. Radiographic and clinical parameters were collected from clinical reports and examination protocols. Radiation dose was measured by a dose–area–product (DAP) meter intrinsic to the angiography system. Our results showed that biplane imaging delivered a significantly greater radiation dose (181.4±121.0 Gycm2) than single-plane imaging (133.6±92.8 Gycm2, p<0.0001). The difference was independent of case type (primary or elective) (p = 0.862), vascular territory (p = 0.519) and operator experience (p = 0.903). No significant difference was found in contrast load between biplane (166.8±62.9 ml) and single-plane imaging (176.8±66.0 ml) (p = 0.302). This non-significant difference was independent of case type (p = 0.551), vascular territory (p = 0.308) and operator experience (p = 0.304). Procedures performed with biplane imaging were significantly longer (55.3±27.8 min) than those with single-plane (48.9±24.2 min, p = 0.010) and, similarly, were not dependent on case type (p = 0.226), vascular territory (p = 0.642) or operator experience (p = 0.094). Biplane imaging resulted in a greater radiation dose and a longer procedural time and delivered a non-significant reduction in contrast load than single-plane imaging. These findings did not support the commonly perceived advantages of using biplane imaging in single-vessel coronary interventional procedures. PMID:20019175

Sadick, V; Reed, W; Collins, L; Sadick, N; Heard, R; Robinson, J

2010-01-01

100

Spatiotemporal object-based image analyses in the Blue Nile area using optical multispectral imagery  

NASA Astrophysics Data System (ADS)

Considering the dramatic change occurred in the Blue Nile region of Sudan, this study is of great value for developing a method for identification of forestland cover extents, integrating rate of changes and causes. The study utilizes three consecutive optical multispectral images, two LANDSAT TM images of 1990 and 1999 as well as TERRA ASTER image of 2009 to evaluate forest cover dynamics during the period 1990 to 2009. The method adopted in this research consists in cross operation of classified images of different points in time, which utilizes the overlaying images to be compared for change detection. New layer of segments was created representing the change areas as well as the overlapped areas of each pair of classified images. Consequently, a series of optimized algorithms have been developed to estimate the change in Land Use Land Cover (LULC). At the fundamental stage, smooth and accurate classified images are very essential for any post-classification change detection technique, which were typically achieved by object-based approach (OB) with overall accuracy 91 %, 93 % and 95 % for the years 1990, 1999 and 2009 respectively. Nine LULC classes were generated from each, i.e. agriculture (Ag.), bare-land (Br.), crop-land (Cr.), dense-forest (DF), grassland (Gr.), orchard (Or.), scattered-forest (SF), settlements (St.) and water (W). Therefore, and considering the dramatic change observed in the area, the fusion operation of multi-temporal data results initially in quite numerous change "from-to" information classes, which allows for aggregation of these classes at any hierarchical level of details. Moreover, the developed approach allows the operator to effectively know the spatial pattern of change, trend and magnitude of the dynamics occurred in each of the classified LULC classes. While many change-detection techniques have been developed, a little has been done to assess the quality of these techniques. Hence, the change maps resulting from cross operation were assessed, which reveals that, the accuracies of the change maps for the two time intervals were consistently high.

El-Abbas, Mustafa M.; Csaplovics, E.

2012-10-01

101

Visualization of peripheral vasodilative indices in human skin by use of red, green, blue images  

NASA Astrophysics Data System (ADS)

We propose a method to visualize the arterial inflow, the vascular resistance, and the venous capacitance in the skin tissue from red, green, blue (RGB) digital color images. The arterial inflow and the venous capacitance in the skin tissue are visualized based on an increase in the rate of change in the total blood concentration and the change of the total blood concentration during upper limb occlusion at a pressure of 50 mmHg. The resultant arterial inflow with the measured mean arterial pressure also provides an image of the vascular resistance in human skin. The arterial inflow, the vascular resistance, and the venous capacitance acquired by the method are well correlated with those obtained from the conventional strain-gauge plethysmograph. The correlation coefficients R between the estimated values by the method and the measurements by the SPG are calculated to be 0.83 (P<0.001) for the arterial inflow, 0.77 (P<0.01) for the vascular resistance, and 0.77 (P<0.01) for the venous capacitance. The arterial inflow and the venous capacitance in the skin tissue are significantly higher in active subjects compared with the sedentary subjects, whereas the vascular resistance was significantly lower in the active subjects compared with the sedentary subjects. The results of the present study indicate the possibility of using the proposed method for evaluating the peripheral vascular functions in human skin.

Nishidate, Izumi; Tanaka, Noriyuki; Kawase, Tatsuya; Maeda, Takaaki; Yuasa, Tomonori; Aizu, Yoshihisa; Yuasa, Tetsuya; Niizeki, Kyuichi

2013-06-01

102

Comparative analysis on viewing angle change in Fresnel and Fourier holographic images reconstructed by a tilted plane wave.  

PubMed

We carry out a comparative analysis on a viewing angle change in Fresnel and Fourier holographic images reconstructed by a tilted plane wave. A tilted plane wave illuminating an on-axis hologram generates a diffractive wave carrying the holographic image in a paraxial region of a new diffraction axis. The reconstructed image in the Fresnel hologram is deformed along the new viewing direction, which is well described as Affine transformation. In the Fourier holographic image, the replica of the image is formed without its deformation when the hologram is placed in the front focal plane of the lens, whereas in the case of a hologram that is located at a distance different from a focal length, image deformation arises. This property is investigated through numerical simulation based on a wide-angle diffraction phenomenon. We also perform a similar interpretation for high-order diffraction images appearing in the sampled Fourier hologram and discuss a method for enlarging the viewing angle of the holographic image. PMID:24922205

Chae, Byung Gyu

2014-05-20

103

[Research on the neas infrared focal plane array detector imaging technology used in the laser warning].  

PubMed

In order to achieve the incoming laser's accurate position, it is necessary to improve the detected laser's direction resolution. The InGaAs focal plane array detector with the type of FPA-320 x 256-C was selected as the core component of the diffraction grating laser warning device. The detection theory of laser wavelength and direction based on diffraction grating was introduced. The drive circuit was designed through the analysis of the detector's performance and parameters. Under the FPGA' s timing control, the detector's analog output was sampled by the high-speed AD. The data was cached to FPGA's extended SRAM, and then transferred to a PC through USB. Labview on a PC collects the raw data for processing and displaying. The imaging experiments were completed with the above method. With the wavelength of 1550 nm and 980 nm laser from different directions the diffraction images were detected. Through analysis the location of the zero order and one order can be determined. According to the grating diffraction theory, the wavelength and the direction of the two-dimensional angle can be calculated. It indicates that the wavelength error is less than 10 nm, and the angle error is less than 1 degrees. PMID:25007645

Wang, Zhi-Bin; Huang, Yan-Fei; Wang, Yao-Li; Zhang, Rui; Wang, Yan-Chao

2014-04-01

104

Band-limited image plane masks for the Terrestrial Planet Finder coronagraph: materials and designs for broadband performance.  

PubMed

Coronagraphs for detection and characterization of exosolar earthlike planets require accurate masks with broadband performance in the visible and near infrared spectrum. Design and fabrication of image plane masks capable of suppressing broadband starlight to 10(-10) level contrast presents technical challenges. We discuss basic approaches, material choices, designs, and fabrication options for image plane masks with particular focus on material properties to obtain adequate spectral performance. Based on theoretical analysis, we show that metals such as Pt and Ni, and alloys such as Inconel, may be employed as promising mask materials that can meet broadband performance requirements. PMID:18188191

Balasubramanian, Kunjithapatham

2008-01-10

105

Second Harmonic Imaging of the Human Brain The Practicability of Coronal Insonation Planes and Alternative Perfusion Parameters  

Microsoft Academic Search

Background and Purpose—Second harmonic imaging (SHI) is a novel ultrasound technique that allows the evaluation of brain tissue perfusion. The purpose of this study was to assess normal cerebral echo contrast characteristics in 3 regions of interest (ROIs) in the transverse axial and coronal insonation planes through the temporal bone window. Materials and Methods—SHI examinations were performed in 25 patients

Judith U. Harrer; Christof Klötzsch

2010-01-01

106

Bi-plane correlation imaging for improved detection of lung nodules Ehsan Samei1,2,3  

E-print Network

the x-ray tube vertically and horizontally with respect to the detector. Each image was analyzed using radiography, digital radiography, stereoscopy, lung nodules, lung cancer, computer aided detection (CAD) 1 approach that utilizes angular information from a bi-plane digital acquisition in conjunction with computer

107

Design and performance of single photon APD focal plane arrays for 3-D LADAR imaging  

NASA Astrophysics Data System (ADS)

×We describe the design, fabrication, and performance of focal plane arrays (FPAs) for use in 3-D LADAR imaging applications requiring single photon sensitivity. These 32 × 32 FPAs provide high-efficiency single photon sensitivity for three-dimensional LADAR imaging applications at 1064 nm. Our GmAPD arrays are designed using a planarpassivated avalanche photodiode device platform with buried p-n junctions that has demonstrated excellent performance uniformity, operational stability, and long-term reliability. The core of the FPA is a chip stack formed by hybridizing the GmAPD photodiode array to a custom CMOS read-out integrated circuit (ROIC) and attaching a precision-aligned GaP microlens array (MLA) to the back-illuminated detector array. Each ROIC pixel includes an active quenching circuit governing Geiger-mode operation of the corresponding avalanche photodiode pixel as well as a pseudo-random counter to capture per-pixel time-of-flight timestamps in each frame. The FPA has been designed to operate at frame rates as high as 186 kHz for 2 ?s range gates. Effective single photon detection efficiencies as high as 40% (including all optical transmission and MLA losses) are achieved for dark count rates below 20 kHz. For these planar-geometry diffused-junction GmAPDs, isolation trenches are used to reduce crosstalk due to hot carrier luminescence effects during avalanche events, and we present details of the crosstalk performance for different operating conditions. Direct measurement of temporal probability distribution functions due to cumulative timing uncertainties of the GmAPDs and ROIC circuitry has demonstrated a FWHM timing jitter as low as 265 ps (standard deviation is ~100 ps).

Itzler, Mark A.; Entwistle, Mark; Owens, Mark; Patel, Ketan; Jiang, Xudong; Slomkowski, Krystyna; Rangwala, Sabbir; Zalud, Peter F.; Senko, Tom; Tower, John; Ferraro, Joseph

2010-08-01

108

The nonuniformity measurement and image processing algorithm evaluation for uncooled microbolometer infrared focal plane arrays  

NASA Astrophysics Data System (ADS)

The great achievements were achieved in the manufacturing of uncooled microbolometer infrared focal plane arrays(UFPA). By this technique infrared system can be made in the formation of small volume, light weight, low price and being portable. It promotes greatly the utilization of infrared system in many fields. The main disadvantage of UFPA is non-uniformity. Despite non-uniformity of UFPA has been greatly improved, non-uniformity still restricts the performance of uncooled infrared system. In this paper, the attention is focused on the technology and methods measuring the non-uniformity of UFPA. The system that can measure the non-uniformity of UFPA and evaluate the image processing algorithms is developed. The measurement system consists of blackbody, infrared optics, control units, processing circuit, high-speed A/D converter, computer and software. To obtain the output signals of UFPA, the drive circuit and control circuit of thermoelectric stabilizer(TEC) of UFPA are developed. In the drive circuit, the CPLD device is employed to insure a small size circuit. In the TEC circuit, a kind of highly integrated and cost-effective, high-effiency, switch-mode driver is used to insure temperature stability of 0.01°C. The system is used to measure non-uniformity of microbolometer detectors which are produced by ULIS company. It can also present the evaluation of algorithm. The results are given and analyzed.

Qian, Yunsheng; Chang, BenKang; Zhang, Junju; Xing, Suxia; Yu, Shuizhong; Yang, Ji

2005-01-01

109

Dual-view plane illumination microscopy for rapid and spatially isotropic imaging.  

PubMed

We describe the construction and use of a compact dual-view inverted selective plane illumination microscope (diSPIM) for time-lapse volumetric (4D) imaging of living samples at subcellular resolution. Our protocol enables a biologist with some prior microscopy experience to assemble a diSPIM from commercially available parts, to align optics and test system performance, to prepare samples, and to control hardware and data processing with our software. Unlike existing light sheet microscopy protocols, our method does not require the sample to be embedded in agarose; instead, samples are prepared conventionally on glass coverslips. Tissue culture cells and Caenorhabditis elegans embryos are used as examples in this protocol; successful implementation of the protocol results in isotropic resolution and acquisition speeds up to several volumes per s on these samples. Assembling and verifying diSPIM performance takes ?6 d, sample preparation and data acquisition take up to 5 d and postprocessing takes 3-8 h, depending on the size of the data. PMID:25299154

Kumar, Abhishek; Wu, Yicong; Christensen, Ryan; Chandris, Panagiotis; Gandler, William; McCreedy, Evan; Bokinsky, Alexandra; Colón-Ramos, Daniel A; Bao, Zhirong; McAuliffe, Matthew; Rondeau, Gary; Shroff, Hari

2014-11-01

110

Plane Groups  

NSDL National Science Digital Library

This is a lengthy PDF document (60 pages+) about plane groups and symmetry. It includes colorful images of each of the 17 plane groups, in several different forms. Additionally, there are some summarizing graphics that show unit cells, lattices, symmetry elements, etc. There is lots here to choose from -- I doubt that anyone will want to use all of the images. Studying plane groups is a good way to introduce crystal systems, point groups, lattices, symmetry operators, etc. All is in 2-D, but it is easy to tell students that the principles are the same in 3-D. For those who like to make changes, the PDF document was created from individual EPS files. This means that the files can be opened in Adobe Illustrator, Corel Draw, etc., and modified to fit your own needs.

Perkins, Dexter

111

Imaging with a 90 frames/s microbolometer focal plane array and high-power terahertz free electron laser  

NASA Astrophysics Data System (ADS)

An uncooled microbolometer focal plane array (FPA) has been developed and used for imaging of objects illuminated by monochromatic coherent radiation of a free electron laser tunable in the range of 1.25-2.5THz. A sensitivity threshold of 1.3×10-3W/cm2 was obtained for the FPA with a homemade absolute interferometric power meter. Videos up to 90frames/s were recorded in both transmission and reflection/scattering modes. When objects were illuminated by laser radiation scattered by a rough metal surface, speckled images were observed. Good quality terahertz images were achieved through the fast rotation of the scatterer.

Dem'yanenko, M. A.; Esaev, D. G.; Knyazev, B. A.; Kulipanov, G. N.; Vinokurov, N. A.

2008-03-01

112

Computer-aided method for automated selection of optimal imaging plane for measurement of total cerebral blood flow by MRI  

NASA Astrophysics Data System (ADS)

A computer-aided method for finding an optimal imaging plane for simultaneous measurement of the arterial blood inflow through the 4 vessels leading blood to the brain by phase contrast magnetic resonance imaging is presented. The method performance is compared with manual selection by two observers. The skeletons of the 4 vessels for which centerlines are generated are first extracted. Then, a global direction of the relatively less curved internal carotid arteries is calculated to determine the main flow direction. This is then used as a reference direction to identify segments of the vertebral arteries that strongly deviates from the main flow direction. These segments are then used to identify anatomical landmarks for improved consistency of the imaging plane selection. An optimal imaging plane is then identified by finding a plane with the smallest error value, which is defined as the sum of the angles between the plane's normal and the vessel centerline's direction at the location of the intersections. Error values obtained using the automated and the manual methods were then compared using 9 magnetic resonance angiography (MRA) data sets. The automated method considerably outperformed the manual selection. The mean error value with the automated method was significantly lower than the manual method, 0.09+/-0.07 vs. 0.53+/-0.45, respectively (p<.0001, Student's t-test). Reproducibility of repeated measurements was analyzed using Bland and Altman's test, the mean 95% limits of agreements for the automated and manual method were 0.01~0.02 and 0.43~0.55 respectively.

Teng, Pang-yu; Bagci, Ahmet Murat; Alperin, Noam

2009-02-01

113

Geiger-mode avalanche photodiode focal plane arrays for three-dimensional imaging LADAR  

NASA Astrophysics Data System (ADS)

We report on the development of focal plane arrays (FPAs) employing two-dimensional arrays of InGaAsP-based Geiger-mode avalanche photodiodes (GmAPDs). These FPAs incorporate InP/InGaAs(P) Geiger-mode avalanche photodiodes (GmAPDs) to create pixels that detect single photons at shortwave infrared wavelengths with high efficiency and low dark count rates. GmAPD arrays are hybridized to CMOS read-out integrated circuits (ROICs) that enable independent laser radar (LADAR) time-of-flight measurements for each pixel, providing three-dimensional image data at frame rates approaching 200 kHz. Microlens arrays are used to maintain high fill factor of greater than 70%. We present full-array performance maps for two different types of sensors optimized for operation at 1.06 ?m and 1.55 ?m, respectively. For the 1.06 ?m FPAs, overall photon detection efficiency of >40% is achieved at <20 kHz dark count rates with modest cooling to ~250 K using integrated thermoelectric coolers. We also describe the first evalution of these FPAs when multi-photon pulses are incident on single pixels. The effective detection efficiency for multi-photon pulses shows excellent agreement with predictions based on Poisson statistics. We also characterize the crosstalk as a function of pulse mean photon number. Relative to the intrinsic crosstalk contribution from hot carrier luminescence that occurs during avalanche current flows resulting from single incident photons, we find a modest rise in crosstalk for multi-photon incident pulses that can be accurately explained by direct optical scattering.

Itzler, Mark A.; Entwistle, Mark; Owens, Mark; Patel, Ketan; Jiang, Xudong; Slomkowski, Krystyna; Rangwala, Sabbir; Zalud, Peter F.; Senko, Tom; Tower, John; Ferraro, Joseph

2010-09-01

114

Implications of image plane line-edge roughness requirements on extreme ultraviolet mask specifications  

SciTech Connect

Line-edge roughness (LER) and the related effect of contact size variation remain as significant challenges facing the commercialization of extreme ultraviolet (EUV) lithography. LER is typically viewed as a resist problem; however, recent simulation results have shown that the mask can indeed be an important contributor. Problems arise from both mask absorber LER as well as mask multilayer roughness leading to random phase variations in the reflected beam (see Fig. 1). The latter effect is especially important as higher coherence off-axis illumination conditions are used and defocus is considered. Here we describe these effect in detail and explore how they will impact EUV mask requirements for the 22-nm half-pitch node and beyond. Figure 2 shows modeling results for 22-nm lines printed in a 0.32-numerical aperture system with 100-nm defocus assuming a mask with 0.24-nm rms multilayer roughness and no absorber edge roughness (unlike the example in Fig. 1). The impact of the phase roughness on the printed line-edge roughness is clearly evident and demonstrates the basic problem with mask roughness. The more detailed modeling-based analysis to be presented will account for performance throughout the process window as well as non-stochastic resist effects. We note that the mean-field resist effect is important to consider because, in practice, the resist is the limiting resolution element in the system and therefore dominates the mask-error enhancement factor (MEEF). As is typically the case with projection-optic-induced MEEF, the resist-induced MEEF will lead to even tighter mask requirements. Note that we do not consider resist stochastic effects since the purpose of this study is isolate mask-induced sources of image-plane roughness.

Naulleau, P. P.; George, Simi A.

2009-02-13

115

High-power blue-violet AlGaN-cladding-free m-plane InGaN/GaN laser diodes  

NASA Astrophysics Data System (ADS)

We demonstrate AlGaN-cladding-free (ACF) m-plane InGaN/GaN laser diodes (LDs) with peak output powers and estimated front facet optical power densities that are comparable to the state-of-the-art single-stripe emitter c-plane LDs. The threshold current density, slope efficiency, and peak output power were 4.66 kA/cm2, 1.29 W/A, and 1.6 W, respectively, after facet coating and under pulsed conditions. Catastrophic optical mirror damage was not observed up to an estimated optical power density of 51.2 MW/cm2 at the front mirror facet, indicating the potential for using ACF m-plane InGaN/GaN LDs in high-power LD applications.

Farrell, R. M.; Haeger, D. A.; Hsu, P. S.; Schmidt, M. C.; Fujito, K.; Feezell, D. F.; DenBaars, S. P.; Speck, J. S.; Nakamura, S.

2011-10-01

116

The WIYN one degree imager 2014: performance of the partially populated focal plane and instrument upgrade path  

NASA Astrophysics Data System (ADS)

The One Degree Imager (ODI) was deployed during the summer of 2012 at the WIYN 3.5m telescope, located on Kitt Peak near Tucson, AZ (USA). ODI is an optical imager designed to deliver atmosphere-limited image quality (? 0.4" FWHM) over a one degree field of view, and uses Orthogonal Transfer Array (OTA) detectors to also allow for on-chip tip/tilt image motion compensation. At this time, the focal plane is partially populated ("pODI") with 13 out of 64 OTA detectors, providing a central scientifically usable field of view of about 24' x 24'; four of the thirteen detectors are installed at outlying positions to probe image quality at all field angles. The image quality has been verified to be indeed better than 0.4'' FWHM over the full field when atmospheric conditions allow. Based on over one year of operations, we summarize pODIs performance and lessons learned. As pODI has proven the viability of the ODI instrument, the WIYN consortium is engaging in an upgrade project to add 12 more detectors to the focal plane enlarging the scientifically usable field of view to about 40' x 40'. A design change in the new detectors has successfully addressed a low light level charge transfer inefficiency.

Harbeck, Daniel R.; Boroson, Todd; Lesser, Michael; Rajagopal, Jayadev; Yeatts, Andrey; Corson, Charles; Liu, Wilson; Dell'Antonio, Ian; Kotulla, Ralf; Ouellette, David; Hooper, Eric; Smith, Mike; Bredthauer, Richard; Martin, Pierre; Muller, Gary; Knezek, Patricia; Hunten, Mark

2014-07-01

117

Enhancement of Optical Polarization Anisotropy of a-Plane InGaN/GaN Multiple Quantum Well Structure from Violet to Blue-Green Light  

NASA Astrophysics Data System (ADS)

A nonpolar a-plane (1120) InGaN/GaN epitaxial layer was grown on r-plane (1012) sapphire substrates by metal-organic chemical vapor deposition (MOCVD). In this work, a set of step-stage multiple quantum wells (MQWs) is inserted between underlying GaN and overlying high indium-content MQWs to investigate its influence on the optical properties of the active region. The step-stage MQWs were deposited by varying growth temperature at fixed precursor flow rate. Optical properties were investigated by the measurement of temperature-dependent photoluminescence (TD-PL). The optical polarization ratio, activation energy, and the smile-like curve in full width at half maximum (FWHM) of PL were analyzed in detail.

Su, Sheng-Han; Huang, Shyh-Jer; Su, Yan-Kuin; Hsu, Hsiao-Chiu

2013-01-01

118

Fabrication of Optical Fourier Transform Hologram Using Blue White He-Cd Laser and Visual Appearance of Reconstructed Color Images  

NASA Astrophysics Data System (ADS)

A blue white He-Cd laser composed of three R/G/B component beams is directly applied to fabricate the optical Fourier transform hologram (OFTH). The visual appearance of reconstructed color hologram images is discussed in contrast to that of an ordinary OFTH which is fabricated using a monochromatic He-Ne laser and diode-pumped solid state(Nd:YAG)laser. The characteristic of He-Cd laser is checked from the viewpoint of the visual size and its place of reconstructed color ghost image called cross talk in the reconstruction process. The visual effect of reconstructed hologram ghost image which can be digitally modified and emphasized by means of commercially available software is discussed through this study.

Kariya, M.; Iizuka, M.; Ookuma, Y.; Nakashima, Y.; Takamatsu, M.

119

New optical modalities utilizing curved focal plane imaging detector devices and large arrays for terrestrial and spaceborne telescopes  

NASA Astrophysics Data System (ADS)

As terrestrial and spaceborne astronomical telescopes advance in multi-functional design sophistication, incorporating greater spectral resolutions, the utilization of curved focal plane ccd and cmos imaging detectors, contoured to match the telescope's Petzval field of curvature, provides a fundamental and novel optical simplicity facilitating new imaging frontiers in astronomical research. For space based telescopes, curved focal plane detector devices require significantly fewer optics than their flat counterparts, which require field flattening optics, in achieving maximum imaging resolutions for adjoining spectrometers or imaging cameras. consequently, with fewer optics comes greater room to place other optics within the same space to accomplish other tasks, providing much greater diversification of observing functions and techniques reserved simultaneously for the telescope. Included within this is the operational capability of producing multi-wavelength spectrometers gathering data concurrently at a multitude of selected wavelengths, with greater sensitivity, reliability, size reduction, and operational longevity of the restructured optical system. Specialized applications involving optical interferometry are also achievable with further enhancements when the curved detectors are applied specifically to refine or maximize detection of fringes, and when employing occulting mask algorithms for existing light paths. for planetary surface mapping space probes, curved focal plane detection provides real-time 3D multi-perspective image acquisition for streaming 3D data sets, replacing onboard or remote computationally intensive 3D reconstructions used for examining terrestrial surface features performed with corresponding flat detectors. For earth based telescopes, where mass of the telescope's optics are not so constrained, more degrees of freedom are also part of the benefits introduced by curved focal plane detector device optimization. Associated with the very large Petzval radii of curvature for very large and extreme telescopes within this class are wide field spatial distortions which are instantaneously corrected when arrays of curved CCD's or CMOS devices are joined homogeneously and precisely together along the converging field of curvature, without field flattening optics, insuring complete full field detection superior to flat facet detectors which compromise the telescope's imaging field curvature detection abilities.

Mark, David

2010-07-01

120

Automatic Bilateral Symmetry Midsagittal Plane Extraction from Pathological 3D Neuroradiological Images  

E-print Network

, bleed, stroke of the human brain can be determined by a symmetry-based analysis of neural scans showing the brain's 3D internal structure. Detecting departures of this internal structure from its normal bilateral the ideal symmetry plane midsagittalwith respect to which the brain is invariant under re ection

121

Quantum Well Infrared Photodetector (QWIP) Focal Planes for Long Wave Imaging  

NASA Technical Reports Server (NTRS)

In this paper, we discuss the development of very sensitive long wavelength infrared GaAs/AlxGa1-xAs quantum well infrared photodetectors (QWIPs) based on bound-to-quasibound intersubband transition, fabrication of light coupling schemes for efficient light coupling, and demonstration of several long wavelength infrared cameras based on QWIP focal plane arrays.

Gunapala, S.; Liu, J. K.; Bandara, S. V.; Hong, W.; Maker, P. D.; Muller, R. E.; Krabach, T. N.

1998-01-01

122

Vortices and Rossby waves in cylinder wakes on a parabolic -plane observed by altimetric imaging velocimetry  

E-print Network

velocimetry Y. D. Afanasyev,1,2 P. B. Rhines,2 and E. G. Lindahl2 1 Memorial University of Newfoundland, St to migrate and radiate. A method for imaging rotating flows, which we call "altimetric imaging velocimetry

Afanassiev, Iakov

123

1024 x 1024 pixel mid-wavelength and long-wavelength infrared QWIP focal plane arrays for imaging applications  

NASA Technical Reports Server (NTRS)

Mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) 10(24) x 10(24) pixel quantum well infrared photodetector (QWIP) focal planes have been demonstrated with excellent imaging performance. The MWIR QWIP detector array has demonstrated a noise equivalent differential temperature (NEAT) of 17 mK at a 95 K operating temperature with f/2.5 optics at 300 K background and the LWIR detector array has demonstrated a NEAT of 13 mK at a 70 K operating temperature with the same optical and background conditions as the MWIR detector array after the subtraction of system noise. Both MWIR and LWIR focal planes have shown background limited performance (BLIP) at 90 K and 70 K operating temperatures respectively, with similar optical and background conditions. In this paper, we will discuss the performance in terms of quantum efficiency, NE(delta)T, uniformity, operability and modulation transfer functions.

Gunapala, S. D.; Bandara, S. V.; Liu, J. K.; Hill, C. J.; Rafol, S. B.; Mumolo, J. M.; Trinh, J. T.; Tidrow, M. Z.; LeVan, P. D.

2005-01-01

124

Active hyperspectral imaging using a quantum cascade laser (QCL) array and digital-pixel focal plane array (DFPA) camera.  

PubMed

We demonstrate active hyperspectral imaging using a quantum-cascade laser (QCL) array as the illumination source and a digital-pixel focal-plane-array (DFPA) camera as the receiver. The multi-wavelength QCL array used in this work comprises 15 individually addressable QCLs in which the beams from all lasers are spatially overlapped using wavelength beam combining (WBC). The DFPA camera was configured to integrate the laser light reflected from the sample and to perform on-chip subtraction of the passive thermal background. A 27-frame hyperspectral image was acquired of a liquid contaminant on a diffuse gold surface at a range of 5 meters. The measured spectral reflectance closely matches the calculated reflectance. Furthermore, the high-speed capabilities of the system were demonstrated by capturing differential reflectance images of sand and KClO3 particles that were moving at speeds of up to 10 m/s. PMID:24977536

Goyal, Anish; Myers, Travis; Wang, Christine A; Kelly, Michael; Tyrrell, Brian; Gokden, B; Sanchez, Antonio; Turner, George; Capasso, Federico

2014-06-16

125

InGaAs focal plane arrays and cameras for man-portable near-infrared imaging  

NASA Astrophysics Data System (ADS)

During this presentation, the status of the technology will be described and prototype applications will be demonstrated and discussed. Included in the discussion will be: (1) the ability to distinguish camouflage from the surrounding environment, (2) the ability to see through fog that is opaque to visible imagers, (3) the ability to image eye-safe lasers for range-finding and target-acquisition, and (4) the use in conjunction with NIR flood lights for both covert surveillance and search and rescue operations. The high room-temperature D* makes indium gallium arsenide focal plane arrays excellent candidates for inclusion in small, light-weight, low-power, and low-cost NIR imaging modules. This type of development will enable additional applications such as the use in gun sights and micro-unmanned aerial vehicle surveillance. The presentation will conclude with the discussion of ongoing development activities.

Ettenberg, Martin H.; Cohen, Marshall J.; Olsen, Gregory H.; Kennedy, James J.

1999-07-01

126

Real-time imaging with THz fully-customized uncooled amorphous-silicon microbolometer focal plane arrays  

NASA Astrophysics Data System (ADS)

Terahertz uncooled antenna-coupled microbolometer focal plane arrays are being developed at CEA-LETI for THz imaging and sensing. This detector technology relies on amorphous silicon bolometer know-how and aims at opening the way to real-time video rate 2D imaging, with potential low cost either in fabrication and in operation. First prototypes of 320x240 pixel arrays have been designed for 1-3 THz sensing. Sensors have been fabricated monolithically above CMOS Integrated Circuits while applying only full Si standard silicon processes. We present the results of extensive work of characterization and simulations made to estimate the sensitivity and spectral absorption of these prototypes. Tests of latest real-time imaging with active illumination by QCLs are then reported while explosives samples were placed in an optical set-up in reflection configuration.

Simoens, F.; Meilhan, J.; Delplanque, B.; Gidon, S.; Lasfargues, G.; Lalanne Dera, J.; Nguyen, D. T.; Ouvrier-Buffet, J. L.; Pocas, S.; Maillou, T.; Cathabard, O.; Barbieri, S.

2012-05-01

127

Methyl green and nitrotetrazolium blue chloride co-expression in colon tissue: A hyperspectral microscopic imaging analysis  

NASA Astrophysics Data System (ADS)

Histological observation of dual-stained colon sections is usually performed by visual observation under a light microscope, or by viewing on a computer screen with the assistance of image processing software in both research and clinical settings. These traditional methods are usually not sufficient to reliably differentiate spatially overlapping chromogens generated by different dyes. Hyperspectral microscopic imaging technology offers a solution for these constraints as the hyperspectral microscopic images contain information that allows differentiation between spatially co-located chromogens with similar but different spectra. In this paper, a hyperspectral microscopic imaging (HMI) system is used to identify methyl green and nitrotetrazolium blue chloride in dual-stained colon sections. Hyperspectral microscopic images are captured and the normalized score algorithm is proposed to identify the stains and generate the co-expression results. Experimental results show that the proposed normalized score algorithm can generate more accurate co-localization results than the spectral angle mapper algorithm. The hyperspectral microscopic imaging technology can enhance the visualization of dual-stained colon sections, improve the contrast and legibility of each stain using their spectral signatures, which is helpful for pathologist performing histological analyses.

Li, Qingli; Liu, Hongying; Wang, Yiting; Sun, Zhen; Guo, Fangmin; Zhu, Jianzhong

2014-12-01

128

Imaging off-plane shear waves with a two-dimensional phononic crystal lens  

Microsoft Academic Search

A two-dimensional flat phononic crystal (PC) lens for focusing off-plane shear waves is proposed. The lens consists of a triangular lattice hole-array, embedded in a solid matrix. The self-collimation effect is employed to guide the shear waves propagating through the lens along specific directions. The Dirichlet-to-Neumann maps (DtN) method is employed to calculate the band structure of the PC, which

Chen-Yu Chiang; Pi-Gang Luan

2010-01-01

129

Simulation of crosstalk and quantum efficiency in high-resolution UV-blue imaging arrays  

NASA Astrophysics Data System (ADS)

The current development of UV-Blue sensitive photo-detectors has lead to investigations with the polywell-stacked gradient poly-homojunction (StaG) configuration. Backwall illumination is of interest due to increased fill factor and pixel wavelength band tailoring. The StaG architecture has benefits. However, for benefit to backwall illumination the space charge region needs to be depleted to the backwall, possibly dispensing with the need for the StaG multi-layer. This research is an initial investigation of the benefit to crosstalk and sensitivity of the deep single well in high resolution, 5 ?m pitch, photodiode arrays. The results indicate that geometries that are of fabricatable morphology can benefit backwall illumination especially in the U/V-blue wavelength spectrum.

Jansz, Paul V.; Hinckley, Steven

2011-12-01

130

Lateral modulation boosts image quality in single plane illumination fluorescence microscopy  

NASA Astrophysics Data System (ADS)

A new microscope combines optical sectioning by fluorophore excitation using a single light sheet with structured illumination. Several images with laterally intensity-modulated light sheets are recorded from scattering fluorescent specimens. By applying a simple data processing scheme, the nonmodulated volumes are identified. The blurred features become dark, and the resultant images are improved in terms of contrast and resolution. Hence, the instrument is capable of discriminating against contributions to the image that are induced by the optical properties of the specimen. The new microscope's capabilities are demonstrated by imaging the internals of the head of an adult Drosophila melanogaster (fruit fly) expressing green fluorescent protein-labeled polycomb proteins.

Breuninger, Tobias; Greger, Klaus; Stelzer, Ernst H. K.

2007-07-01

131

Imaging an off-plane shear wave source with two-dimensional phononic-crystal lens  

Microsoft Academic Search

A two dimensional flat phononic crystal (PC) lens for focusing off-plane\\u000ashear waves is proposed. The lens consists of a triangular lattice hole-array,\\u000aembedded in solid matrix. Self-collimation effect is employed to guide the\\u000ashear waves propagating through the lens along specific directions.\\u000aDirichlet-to-Neumann Maps (DtN) method is employed to calculate the band\\u000astructure of the PC, which can avoid

Chen-Yu Chiang; Pi-Gang Luan

2010-01-01

132

Digital pixel CMOS focal plane array with on-chip multiply accumulate units for low-latency image processing  

NASA Astrophysics Data System (ADS)

A digital pixel CMOS focal plane array has been developed to enable low latency implementations of image processing systems such as centroid trackers, Shack-Hartman wavefront sensors, and Fitts correlation trackers through the use of in-pixel digital signal processing (DSP) and generic parallel pipelined multiply accumulate (MAC) units. Light intensity digitization occurs at the pixel level, enabling in-pixel DSP and noiseless data transfer from the pixel array to the peripheral processing units. The pipelined processing of row and column image data prior to off chip readout reduces the required output bandwidth of the image sensor, thus reducing the latency of computations necessary to implement various image processing systems. Data volume reductions of over 80% lead to sub 10?s latency for completing various tracking and sensor algorithms. This paper details the architecture of the pixel-processing imager (PPI) and presents some initial results from a prototype device fabricated in a standard 65nm CMOS process hybridized to a commercial off-the-shelf short-wave infrared (SWIR) detector array.

Little, Jeffrey W.; Tyrrell, Brian M.; D'Onofrio, Richard; Berger, Paul J.; Fernandez-Cull, Christy

2014-06-01

133

Real-time, continuous-wave terahertz imaging using a microbolometer focal-plane array  

NASA Technical Reports Server (NTRS)

The present invention generally provides a terahertz (THz) imaging system that includes a source for generating radiation (e.g., a quantum cascade laser) having one or more frequencies in a range of about 0.1 THz to about 10 THz, and a two-dimensional detector array comprising a plurality of radiation detecting elements that are capable of detecting radiation in that frequency range. An optical system directs radiation from the source to an object to be imaged. The detector array detects at least a portion of the radiation transmitted through the object (or reflected by the object) so as to form a THz image of that object.

Hu, Qing (Inventor); Min Lee, Alan W. (Inventor)

2010-01-01

134

Direct path planning in image plane and tracking for visual servoing  

NASA Astrophysics Data System (ADS)

The image-based visual servoing would lead to image singularities that might cause control instabilities, and there exit other constraints such as the object should remain in the camera field of view and avoid obstacles. This problem can be solved by coupling path planning and image-based control. The trajectory is planned directly in the image space in our strategy to avoid the 3D estimation of the object, which is required in the motion space based path planning method. In the presented method, the initial path is given using the artificial potential field method without considering the constraints and then genetic algorithm based method is used to check and modify the initial path. This method can achieve satisfactory task while decrease the computation. The proposed method is used to align the micro peg and hole, and the simulation results show that the object can reach its desired position accurately without violation these constrains.

Wang, Junping; Liu, An; Cho, Hyungsuck

2007-10-01

135

Instantaneous three-dimensional visualization of concentration distributions in turbulent flows with crossed-plane laser-induced fluorescence imaging  

NASA Astrophysics Data System (ADS)

A laser-based technique for measuring instantaneous three-dimensional species concentration distributions in turbulent flows is presented. The laser beam from a single laser is formed into two crossed light sheets that illuminate the area of interest. The laser-induced fluorescence (LIF) signal emitted from excited species within both planes is detected with a single camera via a mirror arrangement. Image processing enables the reconstruction of the three-dimensional data set in close proximity to the cutting line of the two light sheets. Three-dimensional intensity gradients are computed and compared to the two-dimensional projections obtained from the two directly observed planes. Volume visualization by digital image processing gives unique insight into the three-dimensional structures within the turbulent processes. We apply this technique to measurements of toluene-LIF in a turbulent, non-reactive mixing process of toluene and air and to hydroxyl (OH) LIF in a turbulent methane-air flame upon excitation at 248 nm with a tunable KrF excimer laser.

Hoffmann, A.; Zimmermann, F.; Scharr, H.; Krömker, S.; Schulz, C.

2005-01-01

136

Red, green, and blue gray-value shift-based approach to whole-field imaging for tissue diagnostics  

NASA Astrophysics Data System (ADS)

Identification of abnormal pathology in situ remains one of the challenges of medicine. The interpretation of tissue conditions relies mainly on optical assessment, which can be difficult due to inadequate visual differences or poor color delineation. We propose a methodology to identify regions of abnormal tissue in a targeted area based on red, green, blue (RGB) shift analysis employing a simple CCD color camera and light-emitting diode illumination in a whole-field-imaging scheme. The concept involves analysis of RGB components in an image with respect to a reference set of RGB values under different illumination wavelengths. The magnitude of the gray value shift is estimated by calculating the Euclidean distance between their normalized RGB coordinates. The shift values obtained using these concepts are thereafter used to construct pseudo-colored images with high contrast, enabling easy identification of abnormal areas in the tissue. Images processed from experiments conducted with excised Wistar rat colon sample (lightly doped with Alexafluor 488) and with simulated tumor (cancer cell pellet placed on colon) showed clear localization of tumor region. This proposed approach and methodology is expected to find potential applications for the in vivo diagnosis of disease.

Valiyambath Krishnan, Mohankumar; Vadakke Matham, Murukeshan; Krishnan, Sathiyamoorthy; Parasuraman, Padmanabhan; Joseph, James; Bhakoo, Kishore

2012-07-01

137

The high resolution X-ray imaging detector planes for the MIRAX mission  

NASA Astrophysics Data System (ADS)

The MIRAX X-ray observatory, the first Brazilian-led astrophysics space mission, is designed to perform an unprecedented wide-field, wide-band hard X-ray (5-200 keV) survey of Galactic X-ray transient sources. In the current configuration, MIRAX will carry a set of four coded-masks telescopes with high spatial resolution Cadmium Zinc Telluride (CZT) detector planes, each one consisting of an array of 64 closely tiled CZT pixelated detectors. Taken together, the four telescopes will have a total detection area of 959 cm2, a large field of view (60° × 60° FWHM), high angular resolution for this energy range (6 arcmin) and very good spectral resolution ( ~ 2 keV @ 60 keV). A stratospheric balloon-borne prototype of one of the MIRAX telescopes has been developed, tested and flown by the Harvard-Smithsonian Center for Astrophysics (CfA) as part of the ProtoEXIST program. In this paper we show results of validation and calibration tests with individual CZT detectors of the ProtoEXIST second generation experiment (P2). Each one of 64 detector units of the P2 detector plane consists of an ASIC, developed by Caltech for the NuSTAR telescope, hybridized to a CZT crystal with 0.6 mm pixel size. The performance of each detector was evaluated using radioactive sources in the laboratory. The calibration results show that the P2 detectors have average energy resolution of ~ 2.1 keV @ 60 keV and 2.3 @ 122 keV. P2 was also successfully tested on near-space environment on a balloon flight, demonstrating the detector unit readiness for integration on a space mission telescope, as well as satisfying all MIRAX mission requirements.

Rodrigues, B. H. G.; Grindlay, J. E.; Allen, B.; Hong, J.; Barthelmy, S.; Braga, J.; D'Amico, F.; Rothschild, R. E.

2013-09-01

138

Plane Wave: Step Scattering  

NSDL National Science Digital Library

The Plane Wave: Step Scattering model simulates the time evolution of a free-particle plane wave in position space when it is incident on a potential energy step.  The position-space wave functions are depicted using three colors on the graph: black depicting the absolute square of the wave function, blue depicting the real part of the wave function, and red depicting the imaginary part of the wave function. The user may change the height of the potential step or the plane wave energy by dragging circles on the energy graph. Also shown is the calculated transmission and reflection coefficients. The Plane Wave: Step Scattering model was created using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_qm_plane_step.jar file will run the program if Java is installed.

Palop, Jose I.

2010-12-13

139

Image method for the derivation of point sources in elastostatic problems with plane interfaces  

NASA Technical Reports Server (NTRS)

An image method algorithm is presented for the derivation of point sources of elastostatics in multilayered media assuming the infinite space point source is known. Specific cases were worked out and shown to coincide with well known solutions in the literature.

Fares, Nabil; Li, Victor C.

1986-01-01

140

Morpho blue Morpho blue  

E-print Network

reproduce nature's highly relective structures3; that is, the wing structure of a Morpho blue butterly of visible-light PCs is to structure materials in all three dimen- sions with spatial period smaller than- tured light is limited only by intrinsic absorption in the underlying material. Sub-100 nm structuring

John, Sajeev

141

Subcellular Biochemical Investigation of Purkinje Neurons Using Synchrotron Radiation Fourier Transform Infrared Spectroscopic Imaging with a Focal Plane Array Detector  

PubMed Central

Coupling Fourier transform infrared spectroscopy with focal plane array detectors at synchrotron radiation sources (SR-FTIR-FPA) has provided a rapid method to simultaneously image numerous biochemical markers in situ at diffraction limited resolution. Since cells and nuclei are well resolved at this spatial resolution, a direct comparison can be made between FTIR functional group images and the histology of the same section. To allow histological analysis of the same section analyzed with infrared imaging, unfixed air-dried tissue sections are typically fixed (after infrared spectroscopic analysis is completed) via immersion fixation. This post fixation process is essential to allow histological staining of the tissue section. Although immersion fixation is a common practice in this filed, the initial rehydration of the dehydrated unfixed tissue can result in distortion of subcellular morphology and confound correlation between infrared images and histology. In this study, vapor fixation, a common choice in other research fields where postfixation of unfixed tissue sections is required, was employed in place of immersion fixation post spectroscopic analysis. This method provided more accurate histology with reduced distortions as the dehydrated tissue section is fixed in vapor rather than during rehydration in an aqueous fixation medium. With this approach, accurate correlation between infrared images and histology of the same section revealed that Purkinje neurons in the cerebellum are rich in cytosolic proteins and not depleted as once thought. In addition, we provide the first direct evidence of intracellular lactate within Purkinje neurons. This highlights the significant potential for future applications of SR-FTIR-FPA imaging to investigate cellular lactate under conditions of altered metabolic demand such as increased brain activity and hypoxia or ischemia. PMID:23638613

2013-01-01

142

AVOIDING THE BLUE ROOF DATA DURING EXTRACTING VEGETATION FROM HIGH RESOLUTION IMAGES  

Microsoft Academic Search

The very high resolution multispectral satellites imagery, such as IKONOS and Quickbird satellite provides a level of detail compatible with urban mapping, it collect images which are a need to classify the land use and land cover in urban sites. Some methods have been developed to extract the information from these images. The texture algorithms for this test area represent

Badawi Rami; Feng XueZhi; Xiao Pengfeng

143

Near-infrared fluorescence imaging of a solitary fibrous tumor of the pancreas using methylene blue  

PubMed Central

A 67-year-old female presented with unexplained abdominal pain. A contrast-enhanced computed tomography scan of the abdomen incidentally revealed a mass in the uncinate process of the pancreas. This mass was resected and based on histopathological findings, diagnosed as a solitary fibrous tumor (SFT) of the pancreas. A SFT is an extremely rare benign mesenchymal tumor that in 65% of cases affects the visceral pleura but can also affect extra-pleural sites. The intraoperative demarcation of pancreatic tumors, such as SFTs, can be challenging. In this report, the first clear intraoperative identification of a SFT of the pancreas in a human was shown using near-infrared fluorescence and methylene blue. PMID:22905287

van der Vorst, Joost R; Vahrmeijer, Alexander L; Hutteman, Merlijn; Bosse, Tjalling; Smit, Vincent THBM; van de Velde, Cornelis JH; Frangioni, John V; Bonsing, Bert A

2012-01-01

144

Experimental validation of optimization concepts for focal-plane image processing with adaptive optics  

NASA Astrophysics Data System (ADS)

We show experimental results demonstrating the feasibility of an extremely fast sequential phase-diversity (SPD) algorithm for point sources. The algorithm can be implemented on a typical adaptive optics (AO) system to improve the wavefront reconstruction beyond the capabilities of a wavefront sensor by using the information from the imaging camera. The algorithm is based on a small-phase approximation enabling fast numerical implementation, and it finds the optimal wavefront correction by iteratively updating the deformable mirror. Our experiments were made at an AO-setup with a 37 actuator membrane mirror, and the results show that the algorithm finds an optimal image quality in 5-10 iterations, when the initial wavefront errors are typical non-common path aberrations having a magnitude of 1-1.5 rad rms. The results are in excellent agreement with corresponding numerical simulations.

Korkiakoski, Visa; Keller, Christoph U.; Doelman, Niek; Fraanje, Rufus; Andrei, Raluca; Verhaegen, Michel

2012-07-01

145

640 x 512 Pixels Long-Wavelength Infrared (LWIR) Quantum-Dot Infrared Photodetector (QDIP) Imaging Focal Plane Array  

NASA Technical Reports Server (NTRS)

Epitaxially grown self-assembled. InAs-InGaAs-GaAs quantum dots (QDs) are exploited for the development of large-format long-wavelength infrared focal plane arrays (FPAs). The dot-in-a-well (DWELL) structures were experimentally shown to absorb both 45 degrees and normal incident light, therefore, a reflection grating structure was used to enhance the quantum efficiency. The devices exhibit peak responsivity out to 8.1 micrometers, with peak detectivity reaching approximately 1 X 10(exp 10) Jones at 77 K. The devices were fabricated into the first long-wavelength 640 x 512 pixel QD infrared photodetector imaging FPA, which has produced excellent infrared imagery with noise equivalent temperature difference of 40 mK at 60-K operating temperature.

Gunapala, Sarath D.; Bandara, Sumith V.; Hill, Cory J.; Ting, David Z.; Liu, John K.; Rafol, Sir B.; Blazejewski, Edward R.; Mumolo, Jason M.; Keo, Sam A.; Krishna, Sanjay; Chang, Y. -C.; Shott, Craig A.

2007-01-01

146

Impacts of Cross-Platform Vicarious Calibration on the Deep Blue Aerosol Retrievals for Moderate Resolution Imaging Spectroradiometer Aboard Terra  

NASA Technical Reports Server (NTRS)

The retrieval of aerosol properties from spaceborne sensors requires highly accurate and precise radiometric measurements, thus placing stringent requirements on sensor calibration and characterization. For the Terra/Moderate Resolution Imaging Spedroradiometer (MODIS), the characteristics of the detectors of certain bands, particularly band 8 [(B8); 412 nm], have changed significantly over time, leading to increased calibration uncertainty. In this paper, we explore a possibility of utilizing a cross-calibration method developed for characterizing the Terral MODIS detectors in the ocean bands by the National Aeronautics and Space Administration Ocean Biology Processing Group to improve aerosol retrieval over bright land surfaces. We found that the Terra/MODIS B8 reflectance corrected using the cross calibration method resulted in significant improvements for the retrieved aerosol optical thickness when compared with that from the Multi-angle Imaging Spectroradiometer, Aqua/MODIS, and the Aerosol Robotic Network. The method reported in this paper is implemented for the operational processing of the Terra/MODIS Deep Blue aerosol products.

Jeong, Myeong-Jae; Hsu, N. Christina; Kwiatkowska, Ewa J.; Franz, Bryan A.; Meister, Gerhard; Salustro, Clare E.

2012-01-01

147

Focal Plane Detectors for the Advanced Gamma-Ray Imaging System (AGIS)  

SciTech Connect

The Advanced Gamma-Ray Imaging System (AGIS) is a concept for the next generation observatory in ground-based very high energy gamma-ray astronomy. Design goals are ten times better sensitivity, higher angular resolution, and a lower energy threshold than existing Cherenkov telescopes. Simulations show that a substantial improvement in angular resolution may be achieved if the pixel diameter is reduced to the order of 0.05 deg, i.e. two to three times smaller than the pixel diameter of current Cherenkov telescope cameras. At these dimensions, photon detectors with smaller physical dimensions can be attractive alternatives to the classical photomultiplier tube (PMT). Furthermore, the operation of an experiment with the size of AGIS requires photon detectors that are among other things more reliable, more durable, and possibly higher efficiency photon detectors. Alternative photon detectors we are considering for AGIS include both silicon photomultipliers (SiPMs) and multi-anode photomultipliers (MAPMTs). Here we present results from laboratory testing of MAPMTs and SiPMs along with results from the first incorporation of these devices into cameras on test bed Cherenkov telescopes.

Otte, A. N.; Williams, D. A. [Santa Cruz Institute for Particle Physics, University of California, 1156 High Street, Santa Cruz, CA 95060 (United States); Byrum, K.; Drake, G.; Horan, D.; Smith, A.; Wagner, R. G. [Argonne National Laboratory (United States); Falcone, A. [Pennsylvania State University (United States); Funk, S.; Tajima, H. [Stanford Linear Accelerator Center (United States); Mukherjee, R. [Barnard College (United States)

2008-12-24

148

In-plane vibration characterization of microelectromechanical systems using acousto-optic modulated partially incoherent stroboscopic imaging  

NASA Astrophysics Data System (ADS)

A technique using acousto-optic modulated partially incoherent stroboscopic imaging for measurement of in-plane motion of microelectromechanical systems (MEMS) is presented. Vibration measurement is allowed by using flashes of the partially incoherent light source to freeze the positions of the microstructure at 12 equally spaced phases of the vibration period. The first-order diffracted beam taken out by an acousto-optic modulator (AOM) from the light beam of a laser is made partially incoherent by a rotating diffuser and then serves as the stroboscopic light source. Both the MEMS excitation signal and the flash control signal are provided by a dual-channel function generator. The main advantage of this measurement method is the absence of a stroboscopic generator and a high speed digital camera. Microscale prototypes are fabricated and tested. Quantitative estimates of the harmonic responses of the prototypes are obtained from the recorded images. The results agree with those obtained with a commercial MEMS motion analyzer TM with relative errors less than 2%.

Wang, Dung-An; Sheu, Fang-Wen; Chiu, Yen-Sih

2011-07-01

149

Noninvasive imaging of human skin hemodynamics using a digital red-green-blue camera  

NASA Astrophysics Data System (ADS)

In order to visualize human skin hemodynamics, we investigated a method that is specifically developed for the visualization of concentrations of oxygenated blood, deoxygenated blood, and melanin in skin tissue from digital RGB color images. Images of total blood concentration and oxygen saturation can also be reconstructed from the results of oxygenated and deoxygenated blood. Experiments using tissue-like agar gel phantoms demonstrated the ability of the developed method to quantitatively visualize the transition from an oxygenated blood to a deoxygenated blood in dermis. In vivo imaging of the chromophore concentrations and tissue oxygen saturation in the skin of the human hand are performed for 14 subjects during upper limb occlusion at 50 and 250 mm Hg. The response of the total blood concentration in the skin acquired by this method and forearm volume changes obtained from the conventional strain-gauge plethysmograph were comparable during the upper arm occlusion at pressures of both 50 and 250 mm Hg. The results presented in the present paper indicate the possibility of visualizing the hemodynamics of subsurface skin tissue.

Nishidate, Izumi; Tanaka, Noriyuki; Kawase, Tatsuya; Maeda, Takaaki; Yuasa, Tomonori; Aizu, Yoshihisa; Yuasa, Tetsuya; Niizeki, Kyuichi

2011-08-01

150

Miniaturized imaging spectrometer based on Fabry-Perot MOEMS filters and HgCdTe infrared focal plane arrays  

NASA Astrophysics Data System (ADS)

Imaging spectrometry can be utilized in the midwave infrared (MWIR) and long wave infrared (LWIR) bands to detect, identify and map complex chemical agents based on their rotational and vibrational emission spectra. Hyperspectral datasets are typically obtained using grating or Fourier transform spectrometers to separate the incoming light into spectral bands. At present, these spectrometers are large, cumbersome, slow and expensive, and their resolution is limited by bulky mechanical components such as mirrors and gratings. As such, low-cost, miniaturized imaging spectrometers are of great interest. Microfabrication of micro-electro-mechanicalsystems (MEMS)-based components opens the door for producing low-cost, reliable optical systems. We present here our work on developing a miniaturized IR imaging spectrometer by coupling a mercury cadmium telluride (HgCdTe)-based infrared focal plane array (FPA) with a MEMS-based Fabry-Perot filter (FPF). The two membranes are fabricated from silicon-oninsulator (SOI) wafers using bulk micromachining technology. The fixed membrane is a standard silicon membrane, fabricated using back etching processes. The movable membrane is implemented as an X-beam structure to improve mechanical stability. The geometries of the distributed Bragg reflector (DBR)-based tunable FPFs are modeled to achieve the desired spectral resolution and wavelength range. Additionally, acceptable fabrication tolerances are determined by modeling the spectral performance of the FPFs as a function of DBR surface roughness and membrane curvature. These fabrication non-idealities are then mitigated by developing an optimized DBR process flow yielding high-performance FPF cavities. Zinc Sulfide (ZnS) and Germanium (Ge) are chosen as the low and the high index materials, respectively, and are deposited using an electron beam process. Simulations are presented showing the impact of these changes and non-idealities in both a device and systems level.

Velicu, S.; Buurma, C.; Bergeson, J. D.; Kim, Tae Sung; Kubby, J.; Gupta, N.

2014-05-01

151

A novel Region of Interest (ROI) imaging technique for biplane imaging in interventional suites: high-resolution small field-of-view imaging in the frontal plane and dose-reduced, large field-of-view standard-resolution imaging in the lateral plane  

PubMed Central

Endovascular-Image-Guided-Interventional (EIGI) treatment of neuro-vascular conditions such as aneurysms, stenosed arteries, and vessel thrombosis make use of treatment devices such as stents, coils, and balloons which have very small feature sizes, 10's of microns to a few 100's of microns, and hence demand a high resolution imaging system. The current state-of-the-art flat panel detector (FPD) has about a 200-um pixel size with the Nyquist of 2.5 lp/mm. For higher-resolution imaging a charge-coupled device (CCD) based Micro-Angio -Fluoroscope (MAF-CCD) with a pixel size of 35um (Nyquist of 11 lp/mm) was developed and previously reported. Although the detector addresses the high resolution needs, the Field-Of-View (FOV) is limited to 3.5 cm × 3.5 cm, which is much smaller than current FPDs. During the use of the MAF-CCD for delicate parts of the intervention, it may be desirable to have real-time monitoring outside the MAF FOV with a low dose, and lower, but acceptable, quality image. To address this need, a novel imaging technique for biplane imaging systems has been developed, using an MAF-CCD in the frontal plane and a dose-reduced standard large FOV imager in the lateral plane. The dose reduction is achieved by using a combination of ROI fluoroscopy and spatially different temporal filtering, a technique that has been previously presented. In order to evaluate this technique, a simulation using images acquired during an actual EIGI treatment on a patient, followed by an actual implementation on phantoms is presented.

Swetadri Vasan, S.N; Ionita, C.; Bednarek, D.R; Rudin, S.

2014-01-01

152

positions and a cursor representing hand position on the mirror. This resulted in a visual image that appeared in the same plane as the hand.  

E-print Network

#12;positions and a cursor representing hand position on the mirror. This resulted in a visual image that appeared in the same plane as the hand. Hand position during the experiment was measured was situated in the center of the workspace, 25 cm from the subject's chest along the body mid- line

153

Identification of anthropogenic and natural dust sources using Moderate Resolution Imaging Spectroradiometer (MODIS) Deep Blue level 2 data  

NASA Astrophysics Data System (ADS)

Mineral dust interacts with radiation and impacts both the regional and global climate. The relative contribution of natural and anthropogenic dust sources, however, remains largely uncertain. Although human activities disturb soils and therefore enhance wind erosion, their contribution to global dust emission has never been directly evaluated because of a lack of data. The retrieval of aerosol properties over land, including deserts, using the Moderate Resolution Imaging Spectroradiometer Deep Blue algorithm makes the first direct characterization of the origin of individual sources possible. In order to separate freshly emitted dust from other aerosol types and aged dust particles, the spectral dependence of the single scattering albedo and the Angstrom wavelength exponent are used. Four years of data from the eastern part of West Africa, which includes one of the most active natural dust sources and the highest population density on the continent, are processed. Sources are identified on the basis of the persistence of significant aerosol optical depth from freshly emitted dust, and the origin is characterized as natural or anthropogenic on the basis of a land use data set. Our results indicate that although anthropogenic dust is observed less frequently and with lower optical depth than dust from natural sources in this particular region, it occupies a large area covering most of northern Nigeria and southern Chad, around Lake Chad. In addition, smaller anthropogenic sources are found as far south as 5° of latitude north, well outside the domain of most dust source inventories.

Ginoux, Paul; Garbuzov, Dmitri; Hsu, N. Christina

2010-03-01

154

Intraoperative two-dimensional echocardiography and color flow Doppler imaging: a basic transesophageal single plane patient examination sequence.  

PubMed Central

Recent advances in technology have allowed application of transesophageal echocardiography to intraoperative care of critically ill patients. Early clinical application primarily involved evaluation of left ventricular regional wall motion. However, valid intraoperative use of transesophageal echocardiography should also encompass systematic assessment of the entire heart as well as the great vessels. This report describes a 10-step sequence of single plane, two-dimensional echocardiographic views which constitute a basic patient examination capable of being performed by a practitioner whose primary responsibility is the delivery of anesthesia care. A 5-step color flow Doppler examination sequence is also presented. These views complement the two-dimensional echocardiographic steps. Representations of methods for grading Doppler-defined valvular regurgitation complete the report. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 Figure 26 PMID:7825339

Rafferty, T. D.; Lippmann, H.

1993-01-01

155

Blue Note  

SciTech Connect

Argonne's Murray Gibson is a physicist whose life's work includes finding patterns among atoms. The love of distinguishing patterns also drives Gibson as a musician and Blues enthusiast."Blue" notes are very harmonic notes that are missing from the equal temperament scale.The techniques of piano blues and jazz represent the melding of African and Western music into something totally new and exciting.

Murray Gibson

2007-04-27

156

Dyed red, green, and blue photoresist for manufacture of high-resolution color filter arrays for image sensors  

NASA Astrophysics Data System (ADS)

We are developing a set of dyed red, green, and blue color filter coatings for the fabrication of high resolution CCD and CMOS image sensor arrays. The resists contain photosensitive polymer binders and various curing agents, soluble organic dyes, and solvents. The new dyed photoresists are sensitive to i-line radiation, primarily at 365 nm, and are negative-working, requiring less than 500 mJ of exposure energy for patterning. The coatings are developed in standard Tetramethylammonium Hydroxide (TMAH) developers. Many dyes were examined in order to achieve the desired spectral properties as well as the meet the solvent solubility and thermal stability requirements. Computer modeling was utilized to determine the correct proportions of dye(s) in each resist, after which the modeling results were verified by actual formulation and testing. Thermal stability of the dyes was determined using isothermal. Thermogravimetric Analysis (TGA) at 200°C for 30 minutes. The dyes were evaluated in both traditional (free radical) and novel polymer systems to see if adequate sensitivity, resolution, and feature quality could be obtained. The studies showed that traditional free radical-based photochemistries are marginal at best for high resolution (1-2 micron) applications. To overcome this limitation, a new polymer system having photodimerizable functional units and acid functional groups was developed to impart photosensitivity and developer solubility, respectively. This system, which does not use free radical-initiated photopolymerization as a mechanism for patterning, shows low exposure dose requirements and is capable of resolving features less than 2 micron in size.

Guerrero, Douglas J.; DiMenna, William; Flaim, Tony D.; Mercado, Ramil; Sun, Sam

2003-05-01

157

Structure-guided engineering of a Pacific Blue fluorophore ligase for specific protein imaging in living cells  

PubMed Central

Mutation of a gatekeeper residue, tryptophan 37, in E. coli lipoic acid ligase (LplA), expands substrate specificity such that unnatural probes much larger than lipoic acid can be recognized. This approach, however, has not been successful for anionic substrates. An example is the blue fluorophore Pacific Blue, which is isosteric to 7-hydroxycoumarin, and yet not recognized by the latter’s ligase (W37VLplA) or any tryptophan 37 point mutant. Here we report the results of a structure-guided, two-residue screening matrix to discover an LplA double mutant, E20G/W37TLplA, that ligates Pacific Blue as efficiently as W37VLplA ligates 7-hydroxycoumarin. The utility of this Pacific Blue ligase for specific labeling of recombinant proteins inside living cells, on the cell surface, and inside acidic endosomes is demonstrated. PMID:21859157

Cohen, Justin D.; Thompson, Samuel; Ting, Alice Y.

2011-01-01

158

Imaging, photophysical properties and DFT calculations of manganese blue (barium manganate(vi) sulphate) - a modern pigment.  

PubMed

Manganese blue is a synthetic barium manganate(vi) sulphate compound that was produced from 1935 to the 1990s and was used both as a blue pigment in works of art and by conservators in the restoration of paintings. The photophysical properties of the compound are described as well as the setup needed to record the spatial distribution of the pigment in works of art. PMID:25051118

Accorsi, Gianluca; Verri, Giovanni; Acocella, Angela; Zerbetto, Francesco; Lerario, Giovanni; Gigli, Giuseppe; Saunders, David; Billinge, Rachel

2014-12-18

159

Chicago blues  

Microsoft Academic Search

I was at STOC this year. At least part of the time. Chicago is a remarkable city, especially so when the Blues Festival is underway. What a contrast! The Chicago Hilton on South Michigan Avenue was the venue of STOC; Grant Park across from the hotel on the shores of Lake Michigan was the site of the Blues Festival---a seething

Rocky Ross

2004-01-01

160

X-ray Microbeam Three-Dimensional Topography Imaging and Strain Analysis of Basal-Plane Dislocations and Threading Edge Dislocations in 4H-SiC  

NASA Astrophysics Data System (ADS)

This paper demonstrates the X-ray microbeam three-dimensional (3D) topography of basal-plane dislocations (BPDs) and threading edge dislocations (TEDs) in 4H-SiC. Stereographic images showing the propagation of BPDs from a substrate to an epilayer and the conversion of BPDs into TEDs near the epilayer/substrate interface are successfully obtained. The narrowing of BPD images is observed just before the BPD-TED conversion points. The images of effective misorientations ?? provide a spatial resolution of 1-2 µm for a TED, and the range of ?? corresponds to strains on the order of +/-10-5. We also discuss the image-formation mechanism in 3D topography.

Tanuma, Ryohei; Mori, Daisuke; Kamata, Isaho; Tsuchida, Hidekazu

2012-06-01

161

Pixel Color Clustering of Multi-Temporally Acquired Digital Photographs of a Rice Canopy by Luminosity-Normalization and Pseudo-Red-Green-Blue Color Imaging  

PubMed Central

Red-green-blue (RGB) channels of RGB digital photographs were loaded with luminosity-adjusted R, G, and completely white grayscale images, respectively (RGwhtB method), or R, G, and R + G (RGB yellow) grayscale images, respectively (RGrgbyB method), to adjust the brightness of the entire area of multi-temporally acquired color digital photographs of a rice canopy. From the RGwhtB or RGrgbyB pseudocolor image, cyan, magenta, CMYK yellow, black, L*, a*, and b* grayscale images were prepared. Using these grayscale images and R, G, and RGB yellow grayscale images, the luminosity-adjusted pixels of the canopy photographs were statistically clustered. With the RGrgbyB and the RGwhtB methods, seven and five major color clusters were given, respectively. The RGrgbyB method showed clear differences among three rice growth stages, and the vegetative stage was further divided into two substages. The RGwhtB method could not clearly discriminate between the second vegetative and midseason stages. The relative advantages of the RGrgbyB method were attributed to the R, G, B, magenta, yellow, L*, and a* grayscale images that contained richer information to show the colorimetrical differences among objects than those of the RGwhtB method. The comparison of rice canopy colors at different time points was enabled by the pseudocolor imaging method.

Doi, Ryoichi; Arif, Chusnul

2014-01-01

162

Blue Sky  

NSDL National Science Digital Library

This activity provides instructions for using a flashlight and aquarium (or other container of water) to explain why the sky is blue and sunsets are red. When the white light from the sun shines through the earth's atmosphere, it collides with gas molecules with the blue light scattering more than the other colors, leaving a dominant yellow-orange hue to the transmitted light. The scattered light makes the sky blue; the transmitted light makes the sunset reddish orange. The section entitled What's Going On? explains this phenomena.

2010-01-01

163

Nile-red and Nile-blue-based near-infrared fluorescent probes for in-cellulo imaging of hydrogen sulfide.  

PubMed

Hydrogen sulfide has recently been identified as a biologically responsive species. The design and synthesis of fluorescence probes, which are constructed with Nile-red or Nile-blue fluorophores and a fluorescence-controllable dinitrophenyl group, for hydrogen sulfide are reported in this paper. The Nile-red-dinitrophenyl-ether-group-based probe (1a) is essentially non-fluorescent because of the inhibition of the photo-induced electron-transfer process; when the dinitrobenzene moiety is removed by nucleophilic substitution with the hydrosulfide anion, probe 1a is converted into hydroxy Nile red, eliciting a H2S-induced fluorescence turn-on signal. Furthermore, probe 1a has high selectivity and sensitivity for the hydrosulfide anion, and its potential for biological applications was confirmed by using it for real-time fluorescence imaging of hydrogen sulfide in live HeLa cells. The Nile-blue-dinitrobenzene-based probe (1b) has gradually diminishing brightness in the red-emission channel with increased hydrogen-sulfide concentration. Thus, this paper reports a comparative study of Nile-red and Nile-blue-based hydrogen-sulfide probes. PMID:25258280

Liu, Xiao-Dong; Fan, Chen; Sun, Ru; Xu, Yu-Jie; Ge, Jian-Feng

2014-11-01

164

Voyager 1 'Blue Movie'  

NASA Technical Reports Server (NTRS)

This is the original Voyager 'Blue Movie' (so named because it was built from Blue filter images). It records the approach of Voyager 1 during a period of over 60 Jupiter days. Notice the difference in speed and direction of the various zones of the atmosphere. The interaction of the atmospheric clouds and storms shows how dynamic the Jovian atmosphere is.

As Voyager 1 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 66 images taken once every Jupiter rotation period (about 10 hours). This time-lapse movie uses images taken every time Jupiter longitude 68W passed under the spacecraft. These images were acquired in the Blue filter from Jan. 6 to Feb. 3 1979. The spacecraft flew from 58 million kilometers to 31 million kilometers from Jupiter during that time.

This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

2000-01-01

165

Full-range in-plane rotation measurement for image recognition with hybrid digital-optical correlator  

NASA Astrophysics Data System (ADS)

A hybrid digital-optical correlator (HDOC) based on volume holographic memory is able to compute the correlation of images at a high speed. HDOC is suitable for real-time image processing and has potential usage in big data processing areas. A 7500-channel HDOC system is experimentally set up, and the target image is correlated with all the channels. The large number of parallel correlation channels could contribute to the precise rotation measurement as well as the translation measurement. In the image recognition applications, the target image involves rotation distortion with respect to the template images. A method with two coarse-fine steps is proposed to measure the rotation at a full range of 360 deg. In the coarse step, the target image is rotated 36 times at an increment of 10 deg. The 36 new images are sent into the HDOC to compute with the template images. Each new image corresponds to a correlation matrix. By searching the smallest value throughout the 36 minimums of the 36 correlation matrixes, the rotation of the target image is narrowed into ±5 deg. In the fine step, the new image is rotated another 10 times at an increment of 1 deg. The rotation measurement error is <0.3 deg.

Zheng, Tianxiang; Cao, Liangcai; He, Qingsheng; Jin, Guofan

2014-01-01

166

Generation speed and reconstructed image quality enhancement of a long-depth object using double wavefront recording planes and a GPU.  

PubMed

A method for fast computer hologram generation for long-depth objects using double wavefront recording planes (WRPs) and a graphics-processing unit (GPU) is presented. The WRPs are placed between the object and the hologram plane. Each WRP records the wavefront from a section of the object. Double WRPs can provide a shorter calculation time and enhanced reconstructed image quality compared with a single WRP, especially for long-depth objects. The average generation speed of two WRPs is 2.5 times that of one WRP. The correlation efficiency of the reconstructed layer relative to the original is 94% for two WRPs and 88.3% for one WRP at the close depth layer. PMID:25090310

Phan, Anh-Hoang; Piao, Mei-lan; Gil, Sang-Keun; Kim, Nam

2014-08-01

167

Effects of stifle flexion angle and scan plane on visibility of the normal canine cranial cruciate ligament using low-field magnetic resonance imaging.  

PubMed

Low-field magnetic resonance imaging (MRI) is commonly used to evaluate dogs with suspected cranial cruciate ligament injury; however, effects of stifle positioning and scan plane on visualization of the ligament are incompletely understood. Six stifle joints (one pilot, five test) were collected from dogs that were scheduled for euthanasia due to reasons unrelated to the stifle joint. Each stifle joint was scanned in three angles of flexion (90°, 135°, 145°) and eight scan planes (three dorsal, three axial, two sagittal), using the same low-field MRI scanner and T2-weighted fast spin echo scan protocol. Two experienced observers who were unaware of scan technique independently scored visualization of the cranial cruciate ligament in each scan using a scale of 0-3. Visualization score rank sums were higher when the stifle was flexed at 90° compared to 145°, regardless of the scan plane. Visualization scores for the cranial cruciate ligament in the dorsal (H (2) = 19.620, P = 0.000), axial (H (2) = 14.633, P = 0.001), and sagittal (H (2) = 8.143, P = 0.017) planes were significantly affected by the angle of stifle flexion. Post hoc analysis showed that the ligament was best visualized at 90° compared to 145° in the dorsal (Z = -3.906, P = 0.000), axial (Z = -3.398, P = 0.001), and sagittal (Z = -2.530, P = 0.011) planes. Findings supported the use of a 90° flexed stifle position for maximizing visualization of the cranial cruciate ligament using low-field MRI in dogs. PMID:24450293

Podadera, Juan; Gavin, Patrick; Saveraid, Travis; Hall, Evelyn; Chau, Jennifer; Makara, Mariano

2014-01-01

168

The Blues  

NSDL National Science Digital Library

Noted bluesman Willie Dixon once said, "The blues are the roots; everything else is the fruits". Wise words indeed, and the quote informs the spirit of Martin Scorsese's PBS documentary series "The Blues". This interactive website provides users with some great material about this seven part series, which features segments by Clint Eastwood, Wim Wenders, and of course, Mr. Scorsese. On the site, visitors can watch previews of each segment and learn more about the artists profiled in each one. In "The Songs & the Artists" area, visitors can read musician biographies and even check out the accompanying radio series which was released in conjunction with the documentary. Those who like to travel should click on the "Blues Road Trip" area. Here they will have the opportunity to take a musical journey from the Deep South to Memphis, St. Louis, and Chicago via song, photographs, and maps. The site is rounded out by the "Blues Classroom" area, which is designed for educators. Interested parties can view lesson plans, look over a blues glossary, and read several background essays.

169

Composite x-ray image assembly for large-field digital mammography with one- and two-dimensional positioning of a focal plane array  

NASA Technical Reports Server (NTRS)

To demonstrate the feasibility of a novel large-field digital mammography technique, a 1024 x 1024 pixel Loral charge-coupled device (CCD) focal plane array (FPA) was positioned in a mammographic field with one- and two-dimensional scan sequences to obtain 950 x 1800 pixel and 3600 x 3600 pixel composite images, respectively. These experiments verify that precise positioning of FPAs produced seamless composites and that the CCD mosaic concept has potential for high-resolution, large-field imaging. The proposed CCD mosaic concept resembles a checkerboard pattern with spacing left between the CCDs for the driver and readout electronics. To obtain a complete x-ray image, the mosaic must be repositioned four times, with an x-ray exposure at each position. To reduce the patient dose, a lead shield with appropriately patterned holes is placed between the x-ray source and the patient. The high-precision motorized translation stages and the fiber-coupled-scintillating-screen-CCD sensor assembly were placed in the position usually occupied by the film cassette. Because of the high mechanical precision, seamless composites were constructed from the subimages. This paper discusses the positioning, image alignment procedure, and composite image results. The paper only addresses the formation of a seamless composite image from subimages and will not consider the effects of the lead shield, multiple CCDs, or the speed of motion.

Halama, G.; McAdoo, J.; Liu, H.

1998-01-01

170

De novo design and spectroscopic characterization of Cu(II)-binding peptides based upon the blue copper protein plastocyanin  

E-print Network

those spectroscopic properties. Most blue copper proteins are similar to either plastocyanin or azurin, the best characterized of the blue copper proteins. All blue copper proteins contain a coordination site where Cu(II) is bound in a trigonal plane...

Daugherty, Roxanne Gail

2012-06-07

171

A MultiChannel Radiometer with Focal Plane Array Antenna for W-Band Passive Millimeterwave Imaging  

Microsoft Academic Search

Passive millimeter wave imaging can complement security measures in scenarios such as airports or checkpoints, due to the fact that these frequencies penetrate clothes and enable e.g. concealed weapon detection (CWD). Such a radiometric system has to meet several key requirements concerning its thermal and spatial resolution and the image acquisition time. The latter can be reduced significantly by scanning

Jiirgen Richter; D. Notel; F. Kloppel; J. Huck; H. Essen; L.-P. Schmidt

2006-01-01

172

Blue Pork  

E-print Network

. The blue glow was an uncommon byproduct of bacterial contamination. Although the health department said the pork was safe to eat after cooking, no one wanted to try. Can you blame them? While westerners will gladly eat Day-Glo orange sweet-and-sour pork...

Hacker, Randi; Boyd, David

2011-05-29

173

A study of the feasibility and performance of an active/passive imager using silicon focal plane arrays and incoherent continuous wave laser diodes  

NASA Astrophysics Data System (ADS)

This dissertation describes an active/passive imager (API) that provides reliable, nighttime, target acquisition in a man-portable package with effective visual range of about 4 kilometers. The reflective imagery is easier to interpret than currently used thermal imagery. Also, in the active mode, the API provides performance equivalent to the big-aperture, thermal systems used on weapons platforms like tanks and attack helicopters. This dissertation describes the research needed to demonstrate both the feasibility and utility of the API. Part of the research describes implementation of a silicon focal plane array (SFPA) capable of both active and passive imaging. The passive imaging mode exceeds the nighttime performance of currently fielded, man-portable sensors. Further, when scene illumination is insufficient for passive imaging, the low dark current of SFPA makes it possible to use continuous wave laser diodes (CWLD) to add an active imaging mode. CWLD have advantages of size, efficiency, and improved eye safety when compared to high peak-power diodes. Because of the improved eye safety, the API provides user-demanded features like video output and extended range gates in the active as well as passive imaging modes. Like any other night vision device, the API depends on natural illumination of the scene for passive operation. Although it has been known for decades that "starlight" illumination is actually from diffuse airglow emissions, the research described in this dissertation provides the first estimates of the global and temporal variation of ground illumination due to airglow. A third related element of the current research establishes the impact of atmospheric aerosols on API performance. We know from day experience that atmospheric scattering of sunlight into the imager line-of-sight can blind the imager and drastically degrade performance. Atmospheric scattering of sunlight is extensively covered in the literature. However, previous literature did not cover the impact of atmospheric scattering when the target is diffusely illuminated by airglow.

Vollmerhausen, Richard H.

174

Rotating in-plane magnetization and real-time magneto-optic imaging of cracks in steel through protective coatings or cladding  

SciTech Connect

The magneto-optic/eddy current imager (MOI) is widely used in the nondestructive inspection (NDI) of aging airframes. By combining magneto-optic imaging and eddy current excitation it is possible to obtain real-time eddy current images of fatigue cracks and areas of hidden corrosion in structures such as the aluminum fuselage of an aircraft. The purpose of this paper is to describe new developments in this technology that permit flux-leakage type imaging of cracks and/or corrosion in steel (e.g., plates, pipes or tanks) through insulation or protective coatings such as stainless steel cladding. Until recently the MOI could not perform such inspections. However, in a project for the Department of Energy Physical Research, Inc. (PRi) significantly advanced the state-of-the-art for the NDI of steel. This was accomplished by developing a method for producing rotating in-plane magnetization in steel and then combining this with real-time magneto-optic imaging.

Fitzpatrick, G.L.; Skaugset, R.L.; Thome, D.K. [Physical Research Inc., Kirkland, WA (United States); Shih, W.C.L. [Physical Research, Inc., Torrance, CA (United States)

1996-12-31

175

Fourier transform infrared spectrochemical imaging: review of design and applications with a focal plane array and multiple beam synchrotron radiation source.  

PubMed

The beamline design, microscope specifications, and initial results from the new mid-infrared beamline (IRENI) are reviewed. Synchrotron-based spectrochemical imaging, as recently implemented at the Synchrotron Radiation Center in Stoughton, Wisconsin, demonstrates the new capability to achieve diffraction limited chemical imaging across the entire mid-infrared region, simultaneously, with high signal-to-noise ratio. IRENI extracts a large swath of radiation (320 hor. × 25 vert. mrads(2)) to homogeneously illuminate a commercial infrared (IR) microscope equipped with an IR focal plane array (FPA) detector. Wide-field images are collected, in contrast to single-pixel imaging from the confocal geometry with raster scanning, commonly used at most synchrotron beamlines. IRENI rapidly generates high quality, high spatial resolution data. The relevant advantages (spatial oversampling, speed, sensitivity, and signal-to-noise ratio) are discussed in detail and demonstrated with examples from a variety of disciplines, including formalin-fixed and flash-frozen tissue samples, live cells, fixed cells, paint cross-sections, polymer fibers, and novel nanomaterials. The impact of Mie scattering corrections on this high quality data is shown, and first results with a grazing angle objective are presented, along with future enhancements and plans for implementation of similar, small-scale instruments. PMID:22524953

Hirschmugl, Carol J; Gough, Kathleen M

2012-05-01

176

Comparison between red-green-blue imaging and visible-near infrared reflectance as potential process analytical tools for monitoring syneresis.  

PubMed

The current work focuses on the comparison of 2 on-line optical sensing systems; namely red-green-blue imaging and visible-near infrared reflectance, for monitoring syneresis during cheese manufacture. The experimental design consisted of 3 temperature treatments carried out in an 11-L cheese vat in triplicate. Both systems were shown to predict syneresis without significant differences in prediction accuracy. However, a single-wavelength near infrared model was the most parsimonious (standard error of prediction=4.35g/100g) for predicting syneresis. This technique was also the simplest in terms of parameters in the model (standard error of prediction=4.15g/100g with 2 parameters), when time after gel cutting and process parameters (temperature and cutting time) were included in the models. The study showed that either system could be employed to control syneresis in cheese manufacture and improve the control of moisture content in cheese. PMID:20412901

Mateo, M J; O'Callaghan, D J; O'Donnell, C P

2010-05-01

177

THE DEEP BLUE COLOR OF HD 189733b: ALBEDO MEASUREMENTS WITH HUBBLE SPACE TELESCOPE/SPACE TELESCOPE IMAGING SPECTROGRAPH AT VISIBLE WAVELENGTHS  

SciTech Connect

We present a secondary eclipse observation for the hot Jupiter HD 189733b across the wavelength range 290-570 nm made using the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. We measure geometric albedos of A{sub g} = 0.40 {+-} 0.12 across 290-450 nm and A{sub g} < 0.12 across 450-570 nm at 1{sigma} confidence. The albedo decrease toward longer wavelengths is also apparent when using six wavelength bins over the same wavelength range. This can be interpreted as evidence for optically thick reflective clouds on the dayside hemisphere with sodium absorption suppressing the scattered light signal beyond {approx}450 nm. Our best-fit albedo values imply that HD 189733b would appear a deep blue color at visible wavelengths.

Evans, Thomas M.; Aigrain, Suzanne; Barstow, Joanna K. [Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Pont, Frederic; Sing, David K. [School of Physics, University of Exeter, EX4 4QL Exeter (United Kingdom); Desert, Jean-Michel; Knutson, Heather A. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Gibson, Neale [European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching (Germany); Heng, Kevin [University of Bern, Center for Space and Habitability, Sidlerstrasse 5, CH-3012 Bern (Switzerland); Lecavelier des Etangs, Alain, E-mail: tom.evans@astro.ox.ac.uk [Institut d'Astrophysique de Paris, UMR7095 CNRS, Universite Pierre et Marie Curie, 98 bis Boulevard Arago, F-75014 Paris (France)

2013-08-01

178

Through-Plane Water Transport Visualization in an Operating PEM Fuel Cell by Visible and Infrared Imaging  

E-print Network

that include x-ray and nuclear magnetic resonance imaging and various spectroscopy methods are hindered cell was observed from the cross-section with a digital microscope and a high resolution infrared transparent (6) cells and neutron radiography (7). With recent improvements in neutron detector technology

Kandlikar, Satish

179

Dielectric-loaded surface plasmon polariton waveguides: Figures of merit and mode characterization by image and Fourier plane leakage microscopy  

NASA Astrophysics Data System (ADS)

Waveguiding of surface plasmon polaritons by dielectric-loaded metal structures is studied in detail by combining numerical simulations and leakage radiation microscopy. These types of waveguides are first numerically investigated using the effective index model and the differential method. We analyzed systematically the influence of the ridge width and thickness of the waveguide on the properties of the surface plasmon guided modes. In particular we investigated the confinement factor of the modes and their associated propagation lengths. These two parameters can be optimized by adjusting the thickness of the dielectric layer. Waveguides loaded with thick and thin dielectric ridges are then optically characterized by leakage radiation microscopy. The mode propagation distance is measured by direct-space imaging and the propagation constants are evaluated by Fourier imaging and analysis. Good agreements are found between theoretical and experimental data.

Grandidier, J.; Massenot, S.; Des Francs, G. Colas; Bouhelier, A.; Weeber, J.-C.; Markey, L.; Dereux, A.; Renger, J.; González, M. U.; Quidant, R.

2008-12-01

180

InSb focal plane array chemical imaging enables assessment of unit process efficiency for milling operation.  

PubMed

In the dry milling of wheat flour, each unit process (roller mill, purifier, sifter, etc.) produces a mixture with varying amounts of wheat endosperm and non-endosperm byproducts. Chemical images with 82 000 pixels of each intermediate product stream issuing from an individual processing machine are readily analyzed in terms of the relative amount of endosperm and non-endosperm. Approximately three minutes is required to produce an image of each intermediate product stream. Applying partial least squares (PLS) chemometric software to identify individual pixels, which enables calculation of the relative amount of endosperm and non-endosperm, is not a time-limiting factor. When relative flow rates are known for each stream, mass balance can be calculated from each intermediate stream in terms of the product (endosperm content) and the lower value non-endosperm byproduct. Data is presented from a purifier in a commercial flour mill. Intermediate streams collected from a run with optimized operational parameters were compared to those of another run before adjustment. The endosperm (product) mass balance profile for each run enabled assessment of operational efficiency. The devised chemical imaging analysis system would be particularly useful in commissioning of a new mill or to optimize existing wheat milling systems. Also, when raw material differs from that for which previous optimization was established, a new optimization may be in order. The ability to acquire a large number of spectra from a specimen and apply multivariate statistics to identify each pixel and subsequently count pixels accommodates heterogeneity and reports the results from averaging a very large number of individual spectra. A second illustration of the utility of the imaging method is presented centering on streams from the first and second break unit operations at the beginning of the roller mill process. PMID:21144147

Wetzel, David L; Posner, Elieser S; Dogan, Hulya

2010-12-01

181

Real-time video rate imaging with a 1k-pixel THz CMOS focal plane array  

NASA Astrophysics Data System (ADS)

Future submillimeter-wave and THz (300GHz-3THz) imaging applications will require low-cost portable systems operating at room-temperature with a video-rate speed and capable of delivering acceptable sensitivity at the very low-power consumption levels to become attractive for truly commercial applications. In particular, CMOS technologies are of interest due to their high integration level offered at a high yield that is capable of massive cost reduction of currently existing THz systems. It has been recently demonstrated that CMOS direct detectors achieve the performance comparable or even superior to the today's existing classical THz devices for active imaging operating at room-temperature. So far, however, only single pixels have been used, allowing only a raster-scan operation. To address this obstacle, we present the very initial work on a 1k-pixel camera chip with a completely integrated readout circuitry and with a full video-rate capability at a power consumption of 2.5?W/pixel. The chip is fully compliant with an industrial bulk CMOS technology and it is intended for active imaging applications. It exhibits a pixel pitch of 80?m, defined by a novel on-chip wire ring antenna, and is designed to accommodate silicon hyper-hemispherical lens for a wide operation bandwidth of at least 0.7-1.1 THz.

Grzyb, J.; Sherry, H.; Zhao, Y.; Al Hadi, R.; Cathelin, A.; Kaiser, A.; Pfeiffer, U.

2012-06-01

182

Design and applications of multi-plane Fresnel color holograms  

NASA Astrophysics Data System (ADS)

The numerical iterative method of design of multi-plane Fresnel holograms is presented. It assumes encoding several flat grayscale images into a single thin phase-only element. Each image is placed at a variable distance and the number of images is not limited, thus many interesting applications can be considered. The paper presents the application of such holograms to reconstruct a colorful two-dimensional image with the use of a single spatial light modulator and three laser beams, i.e. red, green and blue. The given solution helps reduce the total cost of a potential holographic projection device since a single light modulator is used instead of three and no refractive volume optics is necessary to form the final image. The reconstructed three component RGB images overlap to form the color image on the screen. Sub-images are reconstructed simultaneously therefore no time-domain sequential switching is required, which is known to cause the obstructing rainbow effect. The proposed holographic projection method allows to obtain a fine image even when several pixels of the light modulator are damaged. The description of the method is given, followed by the results of numerical simulations.

Makowski, Michal; Sypek, Maciej; Kolodziejczyk, Andrzej

2008-12-01

183

Blue Sky  

NSDL National Science Digital Library

In this optics activity, learners explore why the sky is blue and the sunset is red, using a simple setup comprising a transparent plastic box, water, and powdered milk. Learners use a flashlight to shine a beam of light through the container. Learners look at the beam from the side of the container and then from the end of the tank, and compare the colors that they see. Learners also examine a narrower beam of light. Use this activity to introduce learners to the light spectrum, wavelengths, frequency, scattering, and how all this effects what we see in the sky at different times of the day.

Exploratorium, The

2011-12-07

184

Autofocus technique for three-dimensional imaging, direct-detection laser radar using Geiger-mode avalanche photodiode focal-plane array.  

PubMed

An autofocus technique is proposed for a three-dimensional imaging, direct-detection laser radar system that uses a Geiger-mode avalanche photodiode focal plane array (GmAPD-FPA). This technique is implemented by pointing laser pulses on a target of interest and observing its scattered photon distribution on a GmAPD-FPA. Measuring the standard deviation of the photon distribution on a GmAPD-FPA enables the best focus condition to be found. The feasibility of this technique is demonstrated experimentally by employing a 1 × 8 pixel GmAPD-FPA. It is shown that the spatial resolution improves when the GmAPD-FPA is located in the best focus position found by the autofocus technique. PMID:21165141

Oh, Min Seok; Kong, Hong Jin; Kim, Tae Hoon; Jo, Sung Eun

2010-12-15

185

National Geographic: Blue Whales  

NSDL National Science Digital Library

As a cameraman leans in to get a shot of a blue whale, this massive creature glides through the water off of Costa Rica. That's the opening photograph that visitors to this interactive article from National Geographic are presented with, and it's a rather amazing image. This interactive article and feature is derived from a March 2009 feature in the print edition of National Geographic magazine, and it features the photography of Flip Nicklin and the writing of Ken Brower. The article offers an in-depth look into the recovery of the blue whale population off the coast of Costa Rica in recent years, and along the way visitors can stop off to take a look at a special photo gallery, take a quiz on these remarkable creatures, and also watch a video the provides the story behind one of Nicklin's photographs.

Brower, Ken; Nicklin, Flip

186

Semiconducting layered blue phosphorus: a computational study.  

PubMed

We investigate a previously unknown phase of phosphorus that shares its layered structure and high stability with the black phosphorus allotrope. We find the in-plane hexagonal structure and bulk layer stacking of this structure, which we call "blue phosphorus," to be related to graphite. Unlike graphite and black phosphorus, blue phosphorus displays a wide fundamental band gap. Still, it should exfoliate easily to form quasi-two-dimensional structures suitable for electronic applications. We study a likely transformation pathway from black to blue phosphorus and discuss possible ways to synthesize the new structure. PMID:24836265

Zhu, Zhen; Tománek, David

2014-05-01

187

Semiconducting Layered Blue Phosphorus: A Computational Study  

NASA Astrophysics Data System (ADS)

We investigate a previously unknown phase of phosphorus that shares its layered structure and high stability with the black phosphorus allotrope. We find the in-plane hexagonal structure and bulk layer stacking of this structure, which we call "blue phosphorus," to be related to graphite. Unlike graphite and black phosphorus, blue phosphorus displays a wide fundamental band gap. Still, it should exfoliate easily to form quasi-two-dimensional structures suitable for electronic applications. We study a likely transformation pathway from black to blue phosphorus and discuss possible ways to synthesize the new structure.

Zhu, Zhen; Tománek, David

2014-05-01

188

Blue nightshade poisoning  

MedlinePLUS

Blue nightshade poisoning occurs when someone eats parts of the blue nightshade plant. This is for information only and ... The poison is found in the blue nightshade (Solanum dulcamara) plant, especially in the fruit and leaves.

189

Mongolian blue spots  

MedlinePLUS

Mongolian spots are flat, blue, or blue-gray skin markings near the buttocks that appear at birth or shortly thereafter. ... Mongolian blue spots are common among persons who are of Asian, East Indian, and African descent.

190

The Blue Bottle Revisited.  

ERIC Educational Resources Information Center

Presents a modification of the classic Blue Bottle demonstration that involves the alkaline glucose reduction of methylene blue. Uses other indicators in the classic Blue Bottle to produce a rainbow of colors. (JRH)

Vandaveer, Walter R., IV; Mosher, Mel

1997-01-01

191

The VLA Galactic Plane Survey  

NASA Astrophysics Data System (ADS)

The VLA Galactic Plane Survey (VGPS) is a survey of H I and 21 cm continuum emission in the Galactic plane between longitude 18deg and 67deg with latitude coverage from |b|<1.3d to |b|<2.3d. The survey area was observed with the Very Large Array in 990 pointings. Short-spacing information for the H I line emission was obtained by additional observations with the Green Bank Telescope. H I spectral line images are presented with a resolution of 1'×1'×1.56 km s-1 (FWHM) and an rms noise of 2 K per 0.824 km s-1 channel. Continuum images made from channels without H I line emission have 1' (FWHM) resolution. The VGPS images reveal structures of atomic hydrogen and 21 cm continuum as large as several degrees with unprecedented resolution in this part of the Galaxy. With the completion of the VGPS, it is now possible for the first time to assess the consistency between arcminute-resolution surveys of Galactic H I emission. VGPS images are compared with images from the Canadian Galactic Plane Survey (CGPS) and the Southern Galactic Plane Survey (SGPS). In general, the agreement between these surveys is impressive, considering the differences in instrumentation and image-processing techniques used for each survey. The differences between VGPS and CGPS images are small, <~6 K (rms) in channels in which the mean H I brightness temperature in the field exceeds 80 K. A similar degree of consistency is found between the VGPS and SGPS. The agreement we find between arcminute-resolution surveys of the Galactic plane is a crucial step toward combining these surveys into a single uniform data set that covers 90% of the Galactic disk: the International Galactic Plane Survey. The VGPS data will be made available on the World Wide Web through the Canadian Astronomy Data Centre.

Stil, J. M.; Taylor, A. R.; Dickey, J. M.; Kavars, D. W.; Martin, P. G.; Rothwell, T. A.; Boothroyd, A. I.; Lockman, Felix J.; McClure-Griffiths, N. M.

2006-09-01

192

Why is the sky blue? (Tyndall Effect)  

NSDL National Science Digital Library

This website provides an answer to the common question of âWhy is the sky blue?â The page uses drawings and images to explain how Tyndall Effect causes the blue color we see. Similar topics like Sunsets and âWhy is Mars sky red?â are also addressed.

2007-06-22

193

A high-NA solid immersion objective for imaging a Blue-ray disc and investigating subsurface damage  

NASA Astrophysics Data System (ADS)

Nano-scale resolution in miniature optical systems has been realized in the optical data storage industry. Numerical apertures greater than unity have been achieved in by utilizing the high index material of a hemispherical Solid Immersion Lens (SIL), which increases the resolution of the backing objective by a factor that is related to the refractive index of the SIL. In this research, a custom Hyper-Blu-Disc (HBD) NA=1.4 SIL objective is utilized for high-fidelity readout of data pits beneath a 100?m thick cover layer on an optical Blu-Ray Disc. If realized commercially, the increase in data density could be 3X today's Blu-Ray technology. A distinct difference between this work and other work with SILs in optical data storage is the relatively thick cover layer of 100?m. Recently, there has been interest in discovering new ways to apply the technology and methods used in optical data storage for other means. The inherent design of the HBD objective to image through a shallow layer of dielectric material may lend itself to be used as an effective means for characterizing subsurface damage in optical materials. This research will furthermore investigate the HBD objective as a means of detecting subsurface damage.

Densmore, Victor; Kim, Young Sik; Milster, Tom; Watson, Matt; Kwok, Dolaphine

2014-09-01

194

The outlook for blue-phase LCDs  

NASA Astrophysics Data System (ADS)

Polymer-stabilized blue-phase liquid crystal (BPLC) has become an increasingly important technology trend for information display and photonic applications. BPLC exhibits several attractive features, such as reasonably wide temperature range, submillisecond gray-to-gray response time, no need for alignment layer, optically isotropic voltageoff state, and large cell gap tolerance when an in-plane switching (IPS) cell is employed. Fast response time not only suppresses image blurs, improves the overall transmittance but also enables color sequential display without noticeable color breakup. With time sequential RGB LED colors, the spatial color filters can be eliminated so that both optical efficiency and resolution density are tripled. High optical efficiency helps to reduce power consumption while high resolution density is particularly desirable for the future Ultra High Definition Television. However, some bottlenecks such as high operation voltage, hysteresis, low relaxation frequency, residual birefringence, image sticking, charging issue due to the large capacitance, and relatively low transmittance for the IPS mode, remain to be overcome before widespread application of BPLC can be realized. To reduce operation voltage, both new BPLC materials and new device structures have been investigated. In this paper, we highlight some recent advances in large Kerr constant, fast response time BPLC material development, and new device structures. Especially, we will focus on new BP LCDs with low operation voltage, submillisecond response time, high transmittance, and negligible hysteresis and residual birefringence. The sunrise for BP LCD is near.

Chen, Yuan; Wu, Shin-Tson

2014-02-01

195

Recognition of blue movies by fusion of audio and video  

Microsoft Academic Search

Along with the explosive growth of the Internet, comes the proliferation of pornography. Compared with the pornographic texts and images, blue movies can do much harm to children, due to the greater realism and voyeurism of blue movies. In this paper, a framework for recognizing blue movies by fusing the audio and video information is described. A one-class Gaussian mixture

Haiqiang Zuo; Ou Wu; Weiming Hu; Bo Xu

2008-01-01

196

Blue Cross and Blue Shield of Alabama  

NSDL National Science Digital Library

The Alabama BlueCross and BlueShield Medical Information Server, located and developed by the University of Alabama at Birmingham Department of Computer and Information Sciences, through a grant from Blue Cross and Blue Shield of Alabama for the express purpose of providing Internet access to medical information for all physicians and other health care providers in the state of Alabama. It provides links to a broad range of medical information resources located throughout the Internet. Menus provide information on diseases and disorders, patient care and medical practice, medical specialties, journals and newsletters, health care reform, and other medical information.

1997-01-01

197

Blue InGaN MQW laser diodes on sapphire  

Microsoft Academic Search

We report on the properties of blue InGaN MQW laser diodes fabricated using reactive ion etched facets on c-plane sapphire and cleaved facets on a-plane sapphire. We have also investigated the use of silicon doping in the quantum wells for the etched facet lasers

S. P. DenBaars; A. C. Abare; M. P. Mack; M. Hansen; R. K. Sink; P. Kozodoy; S. Keller; J. S. Speck; J. E. Bowers; U. K. Mishra; L. A. Coldren

1998-01-01

198

Imaging-plate plane-wave x-ray topography of local lattice distribution due to growth striations in silicon crystals  

Microsoft Academic Search

X-ray topography has been employed for observing lattice defects in silicon single crystals,“’ although infrequently for quantitative analysis of crystal imperfections. In recent years, growth striations in magnetic-field-applied Czochralski (MCZ) silicon crystals were investigated using synchrotron plane-wave x-ray topography (PWT) ,3 and local variations in the lattice plane spacing Ad\\/d and orientation Aa were individually determined at a sensitivity of

I. Maekawa; Y. Kudo; S. Kojima; S. Kawado; T. Ishikawa

1993-01-01

199

GPC1 and GPC2: the Pan-STARRS 1.4 gigapixel mosaic focal plane CCD cameras with an on-sky on-CCD tip-tilt image compensation  

NASA Astrophysics Data System (ADS)

We will report on the on-sky, on-CCD, tip-tilt image compensation performance of GPC1, the 1.4 gigapixel mosaic focal plane CCD camera for wide field surveys with a 7 square degree field of view. The camera uses 60 Orthogonal Transfer Arrays (OTAs) with a novel 4 phase pixel architecture and the STARGRASP controller for closed loop multi-guide star centroiding and image correction. The Pan-STARRS project is also constructing GPC2, the second 1.4 gigapixel camera using 64 OTAs. GPC2 will include design enhancements over GPC1 including a new generation of OTAs, titanium mosaic focal plane with adjustable three point kinematic mounts, cyro flex wiring and the recent software distributed over 32 controllers. We will discuss the design, cost, schedule, tools developed, shortcomings and future plans for the two largest digital cameras in the world.

Onaka, P.; Rae, C.; Isani, S.; Tonry, J. L.; Lee, A.; Uyeshiro, R.; Robertson, L.; Ching, G.

2012-07-01

200

Optimal focal-plane restoration  

NASA Technical Reports Server (NTRS)

Image restoration can be implemented efficiently by calculating the convolution of the digital image and a small kernel during image acquisition. Processing the image in the focal-plane in this way requires less computation than traditional Fourier-transform-based techniques such as the Wiener filter and constrained least-squares filter. Here, the values of the convolution kernel that yield the restoration with minimum expected mean-square error are determined using a frequency analysis of the end-to-end imaging system. This development accounts for constraints on the size and shape of the spatial kernel and all the components of the imaging system. Simulation results indicate the technique is effective and efficient.

Reichenbach, Stephen E.; Park, Stephen K.

1989-01-01

201

The Pennsylvania State University Marching Blue Band Blue Band Office  

E-print Network

The Pennsylvania State University Marching Blue Band Press Kit Blue Band Office 101 Blue Band Director vcc2@psu.edu orb1@psu.edu gad157@psu.edu (814) 865 - 3982 #12;History of the Blue Band The Marching Blue Band numbers 310 members which includes: 260 instrumentalists, 34 silks, 14 Touch of Blue

Maroncelli, Mark

202

The Blue Flame Cafe  

NSDL National Science Digital Library

This online biographical encyclopedia of the blues contains entries on almost all of the "great blues singers and singers of the blues." Entries include the pioneers and foundational figures such as Bessie Smith, Robert Johnson, and T-Bone Walker; their lesser-known (outside the Blues community) contemporaries; and their more recent musical heirs such as Stevie Ray Vaughan and Eric Clapton. Each singer's entry includes a concise overview of their influences, career, and musical legacy. Most are also accompanied by a tantalizingly short (only ten seconds) song excerpt in .wav format. A collection of blues links and an internal search engine round out the site.

203

Blue Cross and Blue Shield of Florida is now Florida Blue State Employees' PPO Plan health insurance provider Blue Cross and Blue Shield of  

E-print Network

Blue Cross and Blue Shield of Florida is now Florida Blue State Employees' PPO Plan health insurance provider Blue Cross and Blue Shield of Florida has recently changed its name to Florida Blue Resources Benefits Office at (850) 6444015, or insben@admin.fsu.edu. RELATED LINKS ­ Florida Blue

Ronquist, Fredrik

204

SNAP satellite focal plane development  

Microsoft Academic Search

The proposed SuperNova\\/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square degree field in the visible and near-infrared wavelength regime. The requirements for the instrument suite and the present configuration of the focal plane concept are presented. A two year R&D phase, largely supported by the Department of Energy, is just

Christopher Bebek; Carl W. Akerlof; Greg Aldering; R. Amanullah; Pierre Astier; Charles Baltay; E. Barrelet; Stephane Basa; John Bercovitz; Lars Bergstrom; Gary Berstein; Manfred Bester; Ralph C. Bohlin; Alain Bonissent; Charles R. Bower; Myron Campbell; William C. Carithers Jr.; Eugene D. Commins; C. Day; Susana E. Deustua; Richard S. DiGennaro; Anne Ealet; Richard S. Ellis; William Emmett; Mikael Eriksson; D. Fouchez; Andrew Fruchter; Jean-Francois Genat; Gerson Goldhaber; Ariel Goobar; Donald E. Groom; Henry D. Heetderks; Stephen E. Holland; Dragan Huterer; William E. Johnston; Richard W. Kadel; Armin Karcher; Alex G. Kim; William F. Kolbe; Robin E. Lafever; J. I. Lamoureux; Michael L. Lampton; Oliver Le Fèvre; Michael E. Levi; Daniel S. Levin; Eric V. Linder; Stewart C. Loken; Roger Malina; Alain Mazure; Timothy A. McKay; Shawn P. McKee; Ramon Miquel; Nicholas Morgan; E. Mortsell; N. Mostek; Stuart Mufson; J. A. Musser; Natalie A. Roe; Peter E. Nugent; Hakeem M. Oluseyi; Reynald Pain; Nicholas P. Palaio; David H. Pankow; Saul Perlmutter; Eric Prieto; David Rabinowitz; Alexandre Refregier; Jason Rhodes; Michael S. Schubnell; Michael Sholl; G. Smadja; R. Smith; George F. Smoot; Jeffrey A. Snyder; Anthony Spadafora; Andrew Szymkowiak; Gregory Tarle; Keith Taylor; A. Tilquin; Andrew D. Tomasch; D. Vincent; Henrik von der Lippe; Jean-Pierre Walder; Guobin Wang

2003-01-01

205

Fourier plane filters  

NASA Technical Reports Server (NTRS)

An electrically addressed liquid crystal Fourier plane filter capable of real time optical image processing is described. The filter consists of two parts: a wedge filter having forty 9 deg segments and a ring filter having twenty concentric rings in a one inch diameter active area. Transmission of the filter in the off (transparent) state exceeds fifty percent. By using polarizing optics, contrast as high as 10,000:1 can be achieved at voltages compatible with FET switching technology. A phenomenological model for the dynamic scattering is presented for this special case. The filter is designed to be operated from a computer and is addressed by a seven bit binary word which includes an on or off command and selects any one of the twenty rings or twenty wedge pairs. The overall system uses addressable latches so that once an element is in a specified state, it will remain there until a change of state command is received. The drive for the liquid crystal filter is ? 30 V peak at 30 Hz to 70 Hz. These parameters give a rise time for the scattering of 20 msec and a decay time of 80 to 100 msec.

Oliver, D. S.; Aldrich, R. E.; Krol, F. T.

1972-01-01

206

In Situ Nanoscale In-Plane Deformation Studies of Ultrathin Polymeric Films During Tensile Deformation Using Atomic Force Microscopy and Digital Image Correlation Techniques  

Microsoft Academic Search

The local, nanoscale deformation behavior of ultrathin polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) films used as substrates in magnetic tapes was studied by atomic force microscopy (AFM) and digital image correlation (DIC) techniques. A custom-designed tensile stage was integrated with the AFM to perform uniaxial tension tests on the polymeric films in situ where the film surfaces were imaged

Xiaodong Li; Weijie Xu; Michael A. Sutton; Michael Mello

2007-01-01

207

Blue Crab Fisheries  

NSDL National Science Digital Library

A comprehensive resource on the commercial and recreational blue crab fishery in the Maryland and Virginia waters of the Chesapeake Bay. Explore regulation information for both states, as well as the different gear and methods for catching blue crabs. Though most information pertains to MD and VA, there is an abundance of links to additional information that is not area-specific.

2010-12-01

208

A focal plane visual motion measurement sensor  

Microsoft Academic Search

A motion detection algorithm, based on biological and computational models, for focal plane implementation has been developed. This Temporal Domain Optical Flow Measurement (TDOFM) algorithm uses computational components which have direct and compact electronic counterparts. It uses a binary image of zero-crossings, 2 level analog signals, the signs of spatiotemporal derivatives, 1-b multiplication and pulse widths to measure image velocity.

Ralph Etienne-Cummings; Jan Van der Spiegel; Paul Mueller

1997-01-01

209

A focal plane visual motion measurement sensor  

Microsoft Academic Search

A motion detection algorithm, based on biological and computational models, for focal plane implementation has been developed. This Temporal Domain Optical Flow Measurement (TDOFM) algorithm uses computational components which have direct and compact electronic counterparts. It uses a binary image of zero-crossings, 2 level analog signals, the signs of spatiotemporal derivatives, 1-b multiplication and pulsewidths to measure image velocity. Compared

Ralph Etienne-Cummings; Jan Van der Spiegel; Paul Mueller

1997-01-01

210

Optimization of starshades: focal plane versus pupil plane  

NASA Astrophysics Data System (ADS)

We search for the best possible transmission for an external occulter coronagraph that is dedicated to the direct observation of terrestrial exoplanets. We show that better observation conditions are obtained when the flux in the focal plane is minimized in the zone in which the exoplanet is observed, instead of for the total flux received by the telescope. We describe the transmission of the occulter as a sum of basis functions. For each element of the basis, we numerically computed the Fresnel diffraction at the aperture of the telescope and the complex amplitude at its focus. The basis functions are circular disks that are linearly apodized over a few centimeters (truncated cones). We complemented the numerical calculation of the Fresnel diffraction for these functions by a comparison with pure circular disks (cylinder) for which an analytical expression, based on a decomposition in Lommel series, is available. The technique of deriving the optimal transmission for a given spectral bandwidth is a classical regularized quadratic minimization of intensities, but linear optimizations can be used as well. Minimizing the integrated intensity on the aperture of the telescope or for selected regions of the focal plane leads to slightly different transmissions for the occulter. For the focal plane optimization, the resulting residual intensity is concentrated behind the geometrical image of the occulter, in a blind region for the observation of an exoplanet, and the level of background residual starlight becomes very low outside this image. Finally, we provide a tolerance analysis for the alignment of the occulter to the telescope, which also favors the focal plane optimization. This means that telescope offsets of a few decimeters do not strongly reduce the efficiency of the occulter.

Flamary, R.; Aime, C.

2014-09-01

211

Ground-based CCD astrometry with wide field imagers. IV. An improved geometric-distortion correction for the blue prime-focus camera at the LBT  

NASA Astrophysics Data System (ADS)

High precision astrometry requires an accurate geometric-distortion solution. In this work, we present an average correction for the blue camera of the Large Binocular Telescope which enables a relative astrometric precision of ~15 mas for the BBessel and VBessel broad-band filters. The result of this effort is used in two companion papers: the first to measure the absolute proper motion of the open cluster M 67 with respect to the background galaxies; the second to decontaminate the color-magnitude of M 67 from field objects, enabling the study of the end of its white dwarf cooling sequence. Many other applications might find this distortion correction useful. Based on data acquired using the Large Binocular Telescope (LBT) at Mt. Graham, Arizona, under the Commissioning of the Large Binocular Blue Camera. The LBT is an international collaboration among institutions in the United States, Italy and Germany. LBT Corporation partners are: The University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota and University of Virginia.Visiting Ph.D. Student at STScI under the “2008 graduate research assistantship” program.

Bellini, A.; Bedin, L. R.

2010-07-01

212

Imaging anatomy of the head and spine. A photographic color atlas of MRI, CT, gross and microscopic anatomy in axial, coronal, and sagittal planes  

SciTech Connect

This book presents a correlative display of horizontal, coronal, and sagittal sections of the head and spine with a wide array of MRI images, CT scans, and conventional radiographs. Superb full color illustrations of serial dissections emphasize such clinically important areas as the temporal bone, orbit, and cervical spine. The MRI images included are state of the art, and only the highest resolution CT scans appear.

Schnitzlein, H.N.; Murtagh, F.R.

1985-01-01

213

Decomposing bit planes to reduce compression requirement for lossless channels  

NASA Astrophysics Data System (ADS)

Segmentation of images to bit planes is one of the techniques for scalable image compression. Assuming our source image to be from a uniform quantizer, we categorize its bit planes on the basis of their significance, into two groups called MSB-planes and LSB-planes. The MSB planes contain low-entropy structural information, whereas LSB planes contain high entropy texture information. Due to the different nature of information and entropy of the two groups, they can be coded and reconstructed by different algorithms. The structural nature of MSB planes, make them more compressible at entropy coding stage, whereas the low significance of LSB-planes can be exploited against their high entropy. We realize the later by subsampling of LSB-planes, which in turn requires attention to the close coupling of MSB and LSB planes at the reconstruction stage. We introduce an estimation algorithm for the LSB planes. The reconstructed images are found to be perceptually comparable to the original images. Quantitative comparison also shows significant coding gain in terms of SNR vs. bit rate.

Hayat, Asif; Choi, Tae-Sun

2003-01-01

214

Equivalent Crystal Planes Animation  

NSDL National Science Digital Library

This is a 3-D animation of equivalent crystal planes. It shows the Miller indices linking nodes as a corresponding binary family within braces. This animation is approximately 13 seconds in length and would be useful for understanding the conceptual/imaginary planes have on the crystal behavior.

2009-07-22

215

Optimization of a 3.6-THz quantum cascade laser for real-time imaging with a microbolometer focal plane array  

NASA Astrophysics Data System (ADS)

Real-time imaging in the terahertz (THz) spectral range was achieved using a 3.6-THz quantum cascade laser (QCL) and an uncooled, 160×120 pixel microbolometer camera fitted with a picarin lens. Noise equivalent temperature difference of the camera in the 1-5 THz frequency range was calculated to be at least 3 K, confirming the need for external THz illumination when imaging in this frequency regime. After evaluating the effects of various operating parameters on laser performance, the QCL found to perform optimally at 1.9 A in pulsed mode with a 300 kHz repetition rate and 10-20% duty cycle; average output power was approximately 1 mW. Under this scheme, a series of metallic objects were imaged while wrapped in various obscurants. Single-frame and extended video recordings demonstrate strong contrast between metallic materials and those of plastic, cloth, and paper - supporting the viability of this imaging technology in security screening applications. Thermal effects arising from Joule heating of the laser were found to be the dominant issue affecting output power and image quality; these effects were mitigated by limiting laser pulse widths to 670 ns and operating the system under closed-cycle refrigeration at a temperature of 10 K.

Behnken, Barry N.; Karunasiri, Gamani; Chamberlin, Danielle; Robrish, Peter; Faist, Jérôme

2008-02-01

216

Calculation for computer generated hologram using ray-sampling plane.  

PubMed

We introduce a new algorithm for calculating computer generated hologram (CGH) using ray-sampling (RS) plane. RS plane is set at near the object and the light-rays emitted by the object are sampled at the plane. Then the light-rays are transformed into the wavefront with using the Fourier transforms. The wavefront on the CGH plane is calculated by wavefront propagation simulation from RS plane to CGH plane. The proposed method enables to reproduce high resolution image for deep 3D scene with angular reflection properties such as gloss appearance. PMID:21643163

Wakunami, Koki; Yamaguchi, Masahiro

2011-05-01

217

Beautiful Blue Nile  

NSDL National Science Digital Library

In this lesson students learn about the Blue Nile and compare it to rivers in the United States. They discuss their experiences with rivers and what they think it would be like to travel down a river that rapidly descends from the mountains to the plains. After looking at a map of Ethiopia, students describe what they would see in the area around the Blue Nile. They will witness a demonstration of a river running over flat versus mountainous terrain and view photos of the Blue Nile to describe the terrain.

218

Blue Shark Adventure  

NSDL National Science Digital Library

In this video, Jonathan joins Charlie Donilon on his shark charter boat in Rhode Island, Massachusetts, and learns about how shark tagging has shed light on the biology of and behavior of Blue sharks. Tagging has shown that these incredible swimmers actually migrate completely across the Atlantic ocean. Jonathan tries his hand at tagging a shark and then swims with Blue sharks. We also learn that Blue sharks are not nearly as vicious as they have been reputed to be, and the divers are actually able to pet the sharks! Please see the accompanying study guide for educational objectives and discussion points.

Productions, Jonathan B.

2007-03-01

219

Thermodynamically Stable Blue Phases  

E-print Network

We show theoretically that flexoelectricity stabilizes blue phases in chiral liquid crystals. Induced internal polarization reduces the elastic energy cost of splay and bend deformations surrounding singular lines in the director field. The energy of regions of double twist is unchanged. This in turn reduces the free energy of the blue phase with respect to that of the chiral nematic phase, leading to stability over a wider temperature range. The theory explains the discovery of large temperature range blue phases in highly flexoelectric "bimesogenic" and "bent-core" materials, and predicts how this range may be increased further.

F. Castles; S. M. Morris; E. M. Terentjev; H. J. Coles

2011-01-28

220

The imaging photopolarimeter experiment on pioneer 11.  

PubMed

For 2 weeks continuous imaging, photometry, and polarimetry observations were made of Jupiter and the Galilean satellites in red and blue light from Pioneer 11. Measurements of Jupiter's north and south polar regions were possible because the spacecraft trajectory was highly inclined to the planet's equatorial plane. One of the highest resolution images obtained is presented here along with a comparison of a sample of our photometric and polarimetric data with a simple model. The data seem consistent with increased molecular scattering at high latitudes. PMID:17734364

Baker, A L; Baker, L R; Beshore, E; Blenman, C; Castillo, N D; Chen, Y P; Doose, L R; Elston, J P; Fountain, J W; Gehrels, T; Kendall, J H; Kenknight, C E; Norden, R A; Swindell, W; Tomasko, M G; Coffeen, D L

1975-05-01

221

Holo-television system with a single plane  

Microsoft Academic Search

We show a system capable of projecting a video scene on a white-light holographic screen to obtain a kind of image that results in a plane in front of the screen. This holographic screen is mainly a diffractive lens and it is constructed by holography. The image plane can be located at any azimuth angle and seen with continuous parallax

José J. Lunazzi; Daniel S. F. Magalhães; Noemí I. R. Rivera; Rolando L. Serra

2009-01-01

222

Blue Cross Blue Shield of Massachusetts is an Independent Licensee of the Blue Cross and Blue Shield Association Expanded Coverage for Preventive Care Under  

E-print Network

Blue Cross Blue Shield of Massachusetts is an Independent Licensee of the Blue Cross and Blue. Effect the New Rules Will Have on Members and Accounts Blue Cross Blue Shield of Massachusetts. Blue Cross Blue Shield of Massachusetts will offer the following services with no member cost share

Aalberts, Daniel P.

223

GLAMER - II. Multiple-plane gravitational lensing  

NASA Astrophysics Data System (ADS)

We present an extension to multiple planes of the gravitational lensing code GLAMER. The method entails projecting the mass in the observed light-cone on to a discrete number of lens planes and inverse ray-shooting from the image to the source plane. The mass on each plane can be represented as haloes, simulation particles, a projected mass map extracted form a numerical simulation or any combination of these. The image finding is done in a source-oriented fashion, where only regions of interest are iteratively refined on an initially coarse image plane grid. The calculations are performed in parallel on shared memory machines. The code is able to handle different types of analytic haloes (NFW, NSIE, power law, etc.), haloes extracted from numerical simulations and clusters constructed from semi-analytic models (MOKA). Likewise, there are several different options for modelling the source(s) which can be distributed throughout the light-cone. The distribution of matter in the light-cone can be either taken from a pre-existing N-body numerical simulations, from halo catalogues, or are generated from an analytic mass function. We present several tests of the code and demonstrate some of its applications such as generating mock images of galaxy and galaxy cluster lenses.

Petkova, Margarita; Metcalf, R. Benton; Giocoli, Carlo

2014-12-01

224

A 0.8-?m CMOS two-dimensional programmable mixed-signal focal-plane array processor with on-chip binary imaging and instructions storage  

Microsoft Academic Search

This paper presents a CMOS chip for the parallel acquisition and concurrent analog processing of two-dimensional (2-D) binary images. Its processing function is determined by a reduced set of 19 analog coefficients whose values are programmable with 7-b accuracy. The internal programming signals are analog, but the external control interface is fully digital. On-chip nonlinear digital-to-analog converters (DAC's) map digitally

R. Dominguez-Castro; S. Espejo; A. Rodriguez-Vazquez; R. A. Carmona; P. Foldesy; A. Zarandy; P. Szolgay; T. Sziranyi; T. Roska

1997-01-01

225

Semiconducting Layered Blue Phosphorus: A Computational Study Zhen Zhu and David Tomnek*  

E-print Network

structure and high stability with the black phosphorus allotrope. We find the in-plane hexagonal structure. Unlike graphite and black phosphorus, blue phosphorus displays a wide fundamental band gap. Still study a likely transformation pathway from black to blue phosphorus and discuss possible ways

Tománek, David

226

Choosing between Blue Cross plans...  

E-print Network

Choosing between Blue Cross plans... ...when you have Medicare PresentedPresented By Glenn. Medicare and UC II. Medicare and Anthem Blue Cross III. Plan Comparisons · Pros/Cons · Medical coverage will automatically be enrolled in Part D by Blue Cross No additional Part D premium · Blue Cross members have

Burke, Peter

227

Switching dynamics in cholesteric blue phases  

E-print Network

Blue phases are networks of disclination lines, which occur in cholesteric liquid crystals near the transition to the isotropic phase. They have recently been used for the new generation of fast switching liquid crystal displays. Here we study numerically the steady states and switching hydrodynamics of blue phase I (BPI) and blue phase II (BPII) cells subjected to an electric field. When the field is on, there are three regimes: for very weak fields (and strong anchoring at the boundaries) the blue phases are almost unaffected, for intermediate fields the disclinations twist (for BPI) and unzip (for BPII), whereas for very large voltages the network dissolves in the bulk of the cell. Interestingly, we find that a BPII cell can recover its original structure when the field is switched off, whereas a BPI cell is found to be trapped more easily into metastable configurations. The kinetic pathways followed during switching on and off entails dramatic reorganisation of the disclination networks. We also discuss the effect of changing the director field anchoring at the boundary planes and of varying the direction of the applied field.

A. Tiribocchi; G. Gonnella; D. Marenduzzo; E. Orlandini

2011-03-30

228

Fixed sagittal plane imbalance.  

PubMed

Study Design?Literature review. Objective?To discuss the evaluation and management of fixed sagittal plane imbalance. Methods?A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results?Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis?plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction. PMID:25396111

Savage, Jason W; Patel, Alpesh A

2014-12-01

229

Noninvasive photoacoustic identification of sentinel lymph nodes containing methylene blue in vivo  

E-print Network

Noninvasive photoacoustic identification of sentinel lymph nodes containing methylene blue in vivo both methylene blue and radioactive tracers has a high identification rate, it still relies methylene blue injec- tion in a rat model. We successfully image a SLN with high optical contrast 146

Wang, Lihong

230

Holo-Television System with a Single Plane  

E-print Network

We show a system capable of projecting a video scene on a white-light holographic screen to obtain a kind of image that results in a plane in front of the screen. This holographic screen is mainly a diffractive lens and it is constructed by holography. The image plane can be located at any azimuth angle and seen with continuous parallax and without the use of goggles or any special visualization equipment. The image is not volumetric but when the plane is oblique to the observer its appearance looks very close to a real volumetric image.

Lunazzi, J J; Rivera, N I R; Serra, R L

2009-01-01

231

Holo-television system with a single plane.  

PubMed

We show a system capable of projecting a video scene onto a white-light holographic screen to obtain a kind of image that results in a plane in front of the screen. This holographic screen is mainly a diffractive lens and is constructed by holography. The image plane can be located at any azimuth angle and seen with continuous parallax and without the use of goggles or any special visualization equipment. The image is not volumetric, but when the plane is oblique to the observer its appearance looks very close to a real volumetric image. PMID:19373365

Lunazzi, José J; Magalhães, Daniel S F; Rivera, Noemí I R; Serra, Rolando L

2009-02-15

232

Structure analysis for plane geometry figures  

NASA Astrophysics Data System (ADS)

As there are increasing numbers of digital documents for education purpose, we realize that there is not a retrieval application for mathematic plane geometry images. In this paper, we propose a method for retrieving plane geometry figures (PGFs), which often appear in geometry books and digital documents. First, detecting algorithms are applied to detect common basic geometry shapes from a PGF image. Based on all basic shapes, we analyze the structural relationships between two basic shapes and combine some of them to a compound shape to build the PGF descriptor. Afterwards, we apply matching function to retrieve candidate PGF images with ranking. The great contribution of the paper is that we propose a structure analysis method to better describe the spatial relationships in such image composed of many overlapped shapes. Experimental results demonstrate that our analysis method and shape descriptor can obtain good retrieval results with relatively high effectiveness and efficiency.

Feng, Tianxiao; Lu, Xiaoqing; Liu, Lu; Li, Keqiang; Tang, Zhi

2013-12-01

233

Flame Reconstruction Using Synthetic Aperture Imaging  

E-print Network

Flames can be formed by burning methane (CH4). When oxygen is scarce, carbon particles nucleate into solid particles called soot. These particles emit photons, making the flame yellow. Later, methane is pre-mixed with air forming a blue flame; burning more efficiently, providing less soot and light. Imaging flames and knowing their temperature are vital to maximizing efficiency and validating numerical models. Most temperature probes disrupt the flame and create differences leading to an inaccurate measurement of the flame temperature. We seek to image the flame in three dimensions using synthetic aperture imaging. This technique has already successfully measured velocity fields of a vortex ring [1]. Synthetic aperture imaging is a technique that views one scene from multiple cameras set at different angles, allowing some cameras to view objects that are obscured by others. As the resulting images are overlapped different depths of the scene come into and out of focus, known as focal planes, similar to tomogr...

Murray, Preston; Tree, Dale; Truscott, Tadd

2011-01-01

234

Multiple ring nebulae around blue supergiants  

NASA Astrophysics Data System (ADS)

Context: In the course of the life of a massive star, wind-wind interaction can give rise to the formation of circumstellar nebulae which are both predicted and observed in nature. Aims: We present generic model calculations to predict the properties of such nebulae for blue supergiants. Methods: From stellar evolution calculations including rotation, we obtain the time dependence of the stellar wind properties and of the stellar radiation field. These are used as input for hydro-calculations of the circumstellar medium throughout the star's life. Results: Here, we present the results for a rapidly rotating 12 {M}_? single star. This star forms a blue loop during its post main sequence evolution, at the onset of which its contraction spins it up close to critical rotation. Due to the consequent anisotropic mass loss, the blue supergiant wind sweeps up the preceding slow wind into an hourglass structure. Its collision with the previously formed spherical red supergiant wind shell forms a short-lived luminous nebula consisting of two polar caps and a central inner ring. With time, the polar caps evolve into mid-latitude rings which gradually move toward the equatorial plane while the central ring fades. These structures are reminiscent of the observed nebulae around the blue supergiant Sher 25 and the supernova 1987A. Conclusions: The simple model of an hourglass colliding with a spherical shell reproduces most of the intriguing nebula geometries discovered around blue supergiants, and suggests that they form an evolutionary sequence. Our results indicate that a binary system is not required to obtain them. Appendix A is only available in electronic form at http://www.aanda.org

Chita, S. M.; Langer, N.; van Marle, A. J.; García-Segura, G.; Heger, A.

2008-09-01

235

Diffractive centrosymmetric 3D-transmission phase gratings positioned at the image plane of optical systems transform lightlike 4D-WORLD as tunable resonators into spectral metrics...  

NASA Astrophysics Data System (ADS)

Diffractive 3D phase gratings of spherical scatterers dense in hexagonal packing geometry represent adaptively tunable 4D-spatiotemporal filters with trichromatic resonance in visible spectrum. They are described in the (lambda) - chromatic and the reciprocal (nu) -aspects by reciprocal geometric translations of the lightlike Pythagoras theorem, and by the direction cosine for double cones. The most elementary resonance condition in the lightlike Pythagoras theorem is given by the transformation of the grating constants gx, gy, gz of the hexagonal 3D grating to (lambda) h1h2h3 equals (lambda) 111 with cos (alpha) equals 0.5. Through normalization of the chromaticity in the von Laue-interferences to (lambda) 111, the (nu) (lambda) equals (lambda) h1h2h3/(lambda) 111-factor of phase velocity becomes the crucial resonance factor, the 'regulating device' of the spatiotemporal interaction between 3D grating and light, space and time. In the reciprocal space equal/unequal weights and times in spectral metrics result at positions of interference maxima defined by hyperbolas and circles. A database becomes built up by optical interference for trichromatic image preprocessing, motion detection in vector space, multiple range data analysis, patchwide multiple correlations in the spatial frequency spectrum, etc.

Lauinger, Norbert

1999-08-01

236

Powers of Ten with the Blue Morpho Butterfly  

NSDL National Science Digital Library

This lab, presented by the National Nanotechnology Infrastructure Network, introduces students to the concepts of scale and magnification using a Scanning Electron Microscope (SEM) image of a Blue Morpho butterfly wing. If educators do not have access to an SEM,  images is included with the activity. This lesson will prompt students to think about nanoscale, biomimicry, SEM technology, and measurement. Students will examine the nanostructures of the butterfly's wings using either the images or the SEM (if available). Included in this lab are: teacher guide, student worksheet, and an image of a Blue Morpho butterfly.

2014-09-02

237

The Blue Tube.  

ERIC Educational Resources Information Center

The "Blue Tube" is a 2-part academic package developed at the U.S. Air Force Academy consisting of an English course in communication and writing skills and a management course in advertising and marketing; the two courses are interrelated through student assignments in television production. The first part of the package includes training of…

Wallisch, Bill; Taylor, Bob

238

Greening of Blue Mountain  

Microsoft Academic Search

This article describes the revegetation of Blue Mountain in Palmertown, Pennsylvania, which was biologically destroyed by a zinc smelting operation. After application of industrial fly ash and a municipal sludge mixture, grasses and microbes and some tree seedlings are present. The article outlines in detail the processes of testing and experimentation with the soils and the plants.

W. E. Sopper; J. M. McMahon

1987-01-01

239

Large Blue Butterflies  

NSDL National Science Digital Library

This page deals with research being done on the parasitism of the "blue butterfly" group Maculinea. These species are well known for taking advantage of ants by chemically convincing ants that they are one of their own larvae. This page has some lovely photos, and a nice generalized life history table. Other links deal with aspects of the research including population genetics and communication.

0002-11-30

240

Great Blue Heron  

USGS Multimedia Gallery

Great Blue Herons are found throughout much of North America, but are always associated with water. Because they fish by sight, they need relatively shallow water. Release of too much water through the canals north of the Everglades can interfere with their ability to find food....

2009-12-11

241

Blue light emitting polymers  

Microsoft Academic Search

Polymer light emitting diodes have a good chance to become the main display system in the near future since diodes have many advantages concerning preparation and operation over other display systems. This review focuses on blue light emitting polymers introduced in the literature during the last 10 years. The characteristics of the photoluminescence and electroluminescence of these polymers is reviewed.

D. Y Kim; H. N Cho; C. Y Kim

2000-01-01

242

Blue Crab Education Page  

NSDL National Science Digital Library

Information compiled by the Virginia Institute of Marine Science on the anatomy, life cycle, ecology, and fisheries of the blue crab. Data, research reports, and instructions on eating crabs are all available. Educational resources include lesson plans, teaching tools, and access to online publications. Site serves as an exceptional resource for both beginners and experts.

2010-09-21

243

PLANES, SEMIBIPLANES AND RELATED COMPLEXES  

Microsoft Academic Search

We observe a connection between the problem of lifting semibiplanes to projective planes, and the 1-cohomology of a related cell complex. Examples are provided using the translation planes of order 16. 1. Lifting 'quotients' of planes. Given a projective plane ? with an automorphism group G ? Aut ?, the G-orbits on the points and lines of ? form a

G. ERIC MOORHOUSE

244

The Blue Whale, Balaenoptera musculus  

E-print Network

The Blue Whale, Balaenoptera musculus SALLY A. MIZROCH, DALE W. RICE, and JEFFREY M. BREIWICK Introduction The blue whale, Balaenoptera mus- culus (Linnaeus, 1758), is not only the largest of the whales

245

Conversion of red fluorescent protein into a bright blue probe  

PubMed Central

SUMMARY We utilized a red chromophore formation pathway, in which the anionic red chromophore is formed from the neutral blue intermediate, to suggest a novel rational design strategy to develop blue fluorescent proteins with a tyrosine-based chromophore. The strategy was applied to red fluorescent proteins of the different genetic background such as TagRFP, mCherry, HcRed1, M355NA, and mKeima, which were converted into blue probes. Further improvement of a blue variant of TagRFP using random mutagenesis resulted in an enhanced monomeric protein, mTagBFP, characterized by substantially higher brightness, faster chromophore maturation and higher pH stability than blue fluorescence proteins with a histidine in the chromophore. Detailed biochemical and photochemical analysis indicates mTagBFP is the true monomeric protein tag for multicolor and lifetime imaging as well as the outstanding donor for green fluorescent proteins in FRET applications. PMID:18940671

Subach, Oksana M; Gundorov, Illia S.; Yoshimura, Masami; Subach, Fedor V.; Zhang, Jinghang; Gruenwald, David; Souslova, Ekaterina A.; Chudakov, Dmitriy M.; Verkhusha, Vladislav V.

2008-01-01

246

The Blues Machine M. Cicconet  

E-print Network

for mu- sically untrained people. On the other hand, using computer software to simulate traditional still can not play them, in the sense we play the guitar, for example. 2 Playing Blues The 12-bar blues and harmonized by just three chords. That's why normaly the guitar student starts improvising on the blues scale

247

Blue Sky Innovation  

NSDL National Science Digital Library

The Chicago Tribune has broken new ground with this ambitious initiative to gather news, analysis, and events related to innovation and entrepreneurship. As the site indicates, "Blue Sky informs, inspires and connects an audience that looks at businessâ¦in new ways." Visitors can get started by looking over the short-form news stories on the homepage. Recent pieces have covered the curious barge built by Google, the financial stability of Groupon, and the transformation of event planning via mobile apps. Visitors can look over the event calendar, which brings together information about ongoing activities such as mobile app contests and networking events. The Innovation Hub area is a good place to look around, as it features content gathered from organizations recognized for expertise in the field of innovation. Finally, visitors can sign up to receive updates from Blue Sky via Facebook, Google+, or email.

248

Stabilising the Blue Phases  

E-print Network

We present an investigation of the phase diagram of cholesteric liquid crystals within the framework of Landau - de Gennes theory. The free energy is modified to incorporate all three Frank elastic constants and to allow for a temperature dependent pitch in the cholesteric phase. It is found that the region of stability of the cubic blue phases depends significantly on the value of the elastic constants, being reduced when the bend elastic constant is larger than splay and when twist is smaller than the other two. Most dramatically we find a large increase in the region of stability of blue phase I, and a qualitative change in the phase diagram, in a system where the cholesteric phase displays helix inversion.

G. P. Alexander; J. M. Yeomans

2006-09-22

249

Jonathan Bird's Blue World  

NSDL National Science Digital Library

The Jonathan Bird's Blue World Collection is based on a public television science adventure series and offers science curriculum based videos, lesson plans, activities and the capacity to search by topic, NSES, and geography. These materials illustrate topics such as sound, osmosis and pH with videos of sperm whales, mangroves and coral reefs. These resources can be used by learners of all ages in formal and informal settings.

2012-08-06

250

Blue emitting undecaplatinum clusters.  

PubMed

A blue luminescent 11-atom platinum cluster showing step-like optical features and the absence of plasmon absorption was synthesized. The cluster was purified using high performance liquid chromatography (HPLC). Electrospray ionization (ESI) and matrix assisted laser desorption ionization (MALDI) mass spectrometry (MS) suggest a composition, Pt11(BBS)8, which was confirmed by a range of other experimental tools. The cluster is highly stable and compatible with many organic solvents. PMID:24975972

Chakraborty, Indranath; Bhuin, Radha Gobinda; Bhat, Shridevi; Pradeep, T

2014-08-01

251

Contrast resolution measurement of three primary color of the red, the green and the blue  

Microsoft Academic Search

The color vision contrast resolution is a very important element in human perception and quality assessment for color images. We design a measurement phantom of red, green and blue raster-like to measure the color contrast resolution of three primary color of the red, the green and the blue color based on the digital image processing. The measurement results show that

Yu-Hong Liu; Zhi-Fang Wang; Zheng-Xiang Xie

2010-01-01

252

Statistical algorithm for nonuniformity correction in focal-plane arrays  

E-print Network

-impulse-response filter. The algorithm is applied to infrared data, and the restored images compare favorably with those in the response of focal-plane array infrared imaging systems. The algorithm uses initial scene data to generate infrared imaging systems is known to be strongly affected by the spatial nonuniformity in the photoresponse

Hayat, Majeed M.

253

Best Linear Unbiased Estimate Motivation for BLUE  

E-print Network

1 Chapter 6 Best Linear Unbiased Estimate (BLUE) #12;2 Motivation for BLUE Except for Linear Model to a sub-optimal estimate BLUE is one such sub-optimal estimate Idea for BLUE: 1. Restrict estimate) Advantage of BLUE:Needs only 1st and 2nd moments of PDF Mean & Covariance Disadvantages of BLUE: 1. Sub

Fowler, Mark

254

A novel large scale focal plane telescope using focal plane pointing method  

NASA Astrophysics Data System (ADS)

Large scale focal plane are required by a telescope due to wide field of view with high resolution. Since the detector technology could not accomplish the challenge requirement we developed a focal plane pointing method. This method consists of a pointing mirror and four array detectors. The pointing mirror is placed between the optics and focal plane. As the mirror turns around the optical axis, the light from optics will be reflected to different direction where detector array is placed in the position of focal plane. The key techniques of this method are the pointing accuracy and stability of the pointing mirror and the flatness of the mosaic detector array. Our preliminary experiments indicate that this method is an effective and feasible way to get a large field of view and high resolution image.

Lin, Jianchun; Sun, Liwei; Yong, Chaoliang; Yang, Lin; Chen, Fansheng

255

Holo-television system with a single plane  

Microsoft Academic Search

We show a system capable of projecting a video scene on a white-light\\u000aholographic screen to obtain a kind of image that results in a plane in front\\u000aof the screen. This holographic screen is mainly a diffractive lens and it is\\u000aconstructed by holography. The image plane can be located at any azimuth angle\\u000aand seen with continuous parallax

José J. Lunazzi; Daniel S. F. Magalhães; Noemí I. R. Rivera; Rolando L. Serra

2009-01-01

256

The Three Planes of Language.  

ERIC Educational Resources Information Center

Currently, the language sciences place together four different forms of mental activity on one plane of language, which results in confusion. This paper presents arguments from metaphysics, hermeneutics, and semiotics to demonstrate that there are actually three planes of language (a biologically-based information processing plane, a literal…

Sampson, Gloria

1999-01-01

257

Blue semiconductor nanocrystal laser  

NASA Astrophysics Data System (ADS)

We demonstrate tunable room-temperature amplified spontaneous emission and lasing from blue-emitting core-shell CdS /ZnS nanocrystals (NCs) stabilized in a sol-gel derived silica matrix. Variable stripe length measurements show that these NC-silica composites have a modal gain of ˜100cm-1 at room temperature. Coating microspheres with a NC-silica composite film via a facile process resulted in uniform resonators that exhibit room-temperature lasing over long periods of continuous excitation. This work opens up a spectral window for emission tunable, microscale NC-based lasers.

Chan, Yinthai; Steckel, Jonathan S.; Snee, Preston T.; Caruge, J.-Michel; Hodgkiss, Justin M.; Nocera, Daniel G.; Bawendi, Moungi G.

2005-02-01

258

Flexoelectric blue phases  

E-print Network

We describe the occurence and properties of liquid crystal phases showing two dimensional splay and bend distortions which are stabilised by flexoelectric interactions. These phases are characterised by regions of locally double splayed order separated by topological defects and are thus highly analogous to the blue phases of cholesteric liquid crystals. We present a mean field analysis based upon the Landau--de Gennes Q-tensor theory and construct a phase diagram for flexoelectric structures using analytic and numerical results. We stress the similarities and discrepancies between the cholesteric and flexoelectric cases.

G P Alexander; J M Yeomans

2007-07-01

259

Plant blue-light receptors  

Microsoft Academic Search

Plants have several blue-light receptors, which regulate different aspects of growth and development. Recent studies have identified three such receptors: cryptochrome 1, cryptochrome 2 and phototropin. Cryptochromes 1 and 2 are photolyase-like receptors that regulate hypocotyl growth and flowering time; phototropin mediates phototropism in response to blue light. In addition, phytochrome A has also been found to mediate various blue-light

Chentao Lin

2000-01-01

260

Blue emitting undecaplatinum clusters  

NASA Astrophysics Data System (ADS)

A blue luminescent 11-atom platinum cluster showing step-like optical features and the absence of plasmon absorption was synthesized. The cluster was purified using high performance liquid chromatography (HPLC). Electrospray ionization (ESI) and matrix assisted laser desorption ionization (MALDI) mass spectrometry (MS) suggest a composition, Pt11(BBS)8, which was confirmed by a range of other experimental tools. The cluster is highly stable and compatible with many organic solvents.A blue luminescent 11-atom platinum cluster showing step-like optical features and the absence of plasmon absorption was synthesized. The cluster was purified using high performance liquid chromatography (HPLC). Electrospray ionization (ESI) and matrix assisted laser desorption ionization (MALDI) mass spectrometry (MS) suggest a composition, Pt11(BBS)8, which was confirmed by a range of other experimental tools. The cluster is highly stable and compatible with many organic solvents. Electronic supplementary information (ESI) available: Details of experimental procedures, instrumentation, chromatogram of the crude cluster; SEM/EDAX, DLS, PXRD, TEM, FT-IR, and XPS of the isolated Pt11 cluster; UV/Vis, MALDI MS and SEM/EDAX of isolated 2 and 3; and 195Pt NMR of the K2PtCl6 standard. See DOI: 10.1039/c4nr02778g

Chakraborty, Indranath; Bhuin, Radha Gobinda; Bhat, Shridevi; Pradeep, T.

2014-07-01

261

Plant blue-light receptors.  

PubMed

Plants have several blue-light receptors, which regulate different aspects of growth and development. Recent studies have identified three such receptors: cryptochrome 1, cryptochrome 2 and phototropin. Cryptochromes 1 and 2 are photolyase-like receptors that regulate hypocotyl growth and flowering time; phototropin mediates phototropism in response to blue light. In addition, phytochrome A has also been found to mediate various blue-light responses. Although the signal-transduction mechanisms of blue-light receptors remain largely unclear, phototropin is probably a protein kinase that regulates cytoplasmic calcium concentrations, whereas the cryptochromes might regulate anion-channel activity and changes in gene expression. PMID:10908878

Lin, C

2000-08-01

262

Robust ground plane detection for obstacle avoidance of mobile robots using a monocular camera  

Microsoft Academic Search

This paper presents a vision-based obstacle avoidance design using a monocular camera onboard a mobile robot. An image processing procedure is developed to estimate distances between the robot and obstacles based-on inverse perspective transformation (IPT) in image plane. A robust image processing solution is proposed to detect and segment navigatable ground plane area within the camera view. The proposed method

Chia-How Lin; Sin-Yi Jiang; Yueh-Ju Pu; Kai-Tai Song

2010-01-01

263

Phase-error correction for multiple planes using a sharpness metric  

Microsoft Academic Search

Phase errors in multiple planes create an anisoplanatic (space-variant) blur in an image. We show how phase errors in multiple planes can be corrected with the use of a sharpness metric for heterodyne or holo- graphic imaging. We derive the theoretical framework necessary for this anisoplanatic imaging situation. A digital simulation and results are presented. We demonstrate the success of

Abbie E. Tippie; James R. Fienup

2009-01-01

264

Jupiter in blue, ultraviolet and near infrared  

NASA Technical Reports Server (NTRS)

These three images of Jupiter, taken through the narrow angle camera of NASA's Cassini spacecraft from a distance of 77.6 million kilometers (48.2 million miles) on October 8, reveal more than is apparent to the naked eye through a telescope.

The image on the left was taken through the blue filter. The one in the middle was taken in the ultraviolet. The one on the right was taken in the near infrared.

The blue-light filter is within the part of the electromagnetic spectrum detectable by the human eye. The appearance of Jupiter in this image is, consequently, very familiar. The Great Red Spot (below and to the right of center) and the planet's well-known banded cloud lanes are obvious. The brighter bands of clouds are called zones and are probably composed of ammonia ice particles. The darker bands are called belts and are made dark by particles of unknown composition intermixed with the ammonia ice.

Jupiter's appearance changes dramatically in the ultraviolet and near infrared images. These images are near negatives of each other and illustrate the way in which observations in different wavelength regions can reveal different physical regimes on the planet.

All gases scatter sunlight efficiently at short wavelengths; this is why the sky appears blue on Earth. The effect is even more pronounced in the ultraviolet. The gases in Jupiter's atmosphere, above the clouds, are no different. They scatter strongly in the ultraviolet, making the deep banded cloud layers invisible in the middle image. Only the very high altitude haze appears dark against the bright background. The contrast is reversed in the near infrared, where methane gas, abundant on Jupiter but not on Earth, is strongly absorbing and therefore appears dark. Again the deep clouds are invisible, but now the high altitude haze appears relatively bright against the dark background. High altitude haze is seen over the poles and the equator.

The Great Red Spot, prominent in all images, is obviously a feature whose influence extends high in the atmosphere. As the Cassini cameras continue to return images of Jupiter, it will be possible to construct a three-dimensional picture of how clouds form and evolve by watching the changing appearance of Jupiter in different spectral regions.

JPL manages the Cassini mission for NASA's Office of Space Science, Washington, D.C. JPl is a division of the California Institute of Technology in Pasadena.

2000-01-01

265

Blue Care Elect Enhanced Value (PPO)  

E-print Network

Blue Care Elect SM Enhanced Value (PPO) Summary of Benefits Williams College An Association of Independent Blue Cross and Blue Shield Plans This health plan meets Minimum Creditable Coverage Standards of your directory, call Member Service at the number on your ID card. ·Visit the Blue Cross Blue Shield

Aalberts, Daniel P.

266

Blue Ocean vs. Five Forces  

Microsoft Academic Search

The article reports on the authors' research in the Netherlands which focused on a profit model in Dutch retail stores and a so-called blue-ocean approach which requires a new market that attracts consumers and increases profits. Topics include the competitive strategy approach to increasing profits. The authors conclude that the blue-ocean strategy or innovation approach is sustainable.

A. E. Burke; Stel van A. J; A. R. Thurik

2010-01-01

267

Melanoma and satellite blue papule  

PubMed Central

The colors that are seen in dermoscopy depend on the anatomic level of the skin at which the chromophores are seen. Blue color can be found in a variety of melanocytic and nonmelanocytic lesions. An 89-year-old man presented with a 3-year history of a slow-growing, hyperpigmented patch located on the distal third of the right arm. Dermoscopy showed an atypical network, irregularly distributed globules, pigmented internal streaks and a milky-red area. Based on these findings a diagnosis of slow-growing malignant melanoma was made. Simultaneously, a well-defined blue papule was seen on the proximal third of the same arm. Dermoscopy disclosed a homogeneous blue pattern. After clinical and dermoscopic correlation our differential diagnosis for this blue lesion included cutaneous melanoma metastasis, blue nevus and foreign body reaction. The patient recalled its onset 75 years ago after a grenade explosion. We also discuss the blue lesion appearance under reflectance confocal microscopy and high-definition optical coherence tomography. Histopathological examination after excision of the hyperpigmented patch and blue papule revealed a melanoma in situ and a foreign body reaction, respectively. The diagnostic evaluation of a blue lesion should always rely on the integration of all data, especially clinical and dermoscopic features. Other non-invasive techniques, like reflectance confocal microscopy and high-definition optical coherence tomography can also be important aids for its differential diagnosis. PMID:25126462

Oliveira, Andre; Arzberger, Edith; Massone, Cesare; Zalaudek, Iris; Fink-Puches, Regina; Hofmann-Wellenhof, Rainer

2014-01-01

268

Melanoma and satellite blue papule.  

PubMed

The colors that are seen in dermoscopy depend on the anatomic level of the skin at which the chromophores are seen. Blue color can be found in a variety of melanocytic and nonmelanocytic lesions. An 89-year-old man presented with a 3-year history of a slow-growing, hyperpigmented patch located on the distal third of the right arm. Dermoscopy showed an atypical network, irregularly distributed globules, pigmented internal streaks and a milky-red area. Based on these findings a diagnosis of slow-growing malignant melanoma was made. Simultaneously, a well-defined blue papule was seen on the proximal third of the same arm. Dermoscopy disclosed a homogeneous blue pattern. After clinical and dermoscopic correlation our differential diagnosis for this blue lesion included cutaneous melanoma metastasis, blue nevus and foreign body reaction. The patient recalled its onset 75 years ago after a grenade explosion. We also discuss the blue lesion appearance under reflectance confocal microscopy and high-definition optical coherence tomography. Histopathological examination after excision of the hyperpigmented patch and blue papule revealed a melanoma in situ and a foreign body reaction, respectively. The diagnostic evaluation of a blue lesion should always rely on the integration of all data, especially clinical and dermoscopic features. Other non-invasive techniques, like reflectance confocal microscopy and high-definition optical coherence tomography can also be important aids for its differential diagnosis. PMID:25126462

Oliveira, André; Arzberger, Edith; Massone, Cesare; Zalaudek, Iris; Fink-Puches, Regina; Hofmann-Wellenhof, Rainer

2014-07-01

269

High-speed dynamic 3D photoacoustic imaging of sentinel lymph node in a murine model using an ultrasound array  

E-print Network

- operatively to locate the SLN with a handheld gamma probe, followed by a blue dye e.g., methylene blue imaging of the uptake and clearance dynamics of Evans blue dye in SLNs. The photoacoustic imaging system and is convenient to use. Upon injection of Evans blue, a blue dye currently used in clinical SLN biopsy, SLNs

Wang, Lihong

270

Ascorbic Acid and Methylene Blue  

NSDL National Science Digital Library

The WebWare molecules of the month for May are featured in several articles in this issue. "Arsenic: Not So Evil After All?" discusses the pharmaceutical uses of methylene blue and its development as the first synthetic drug used against a specific disease. The JCE Classroom Activity "Out of the Blue" and the article "Greening the Blue Bottle" feature methylene blue and ascorbic acid as two key ingredients in the formulation of the blue bottle. You can also see a colorful example of these two molecules in action on the cover. "Sailing on the 'C': A Vitamin Titration with a Twist" describes an experiment to determine the vitamin C (ascorbic acid) content of citrus fruits and challenges students, as eighteenth-century sea captains, to decide the best fruit to take on a long voyage.

271

Towards Dualband Megapixel QWIP Focal Plane Arrays  

NASA Technical Reports Server (NTRS)

Mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) 1024 x 1024 pixel quantum well infrared photodetector (QWIP) focal planes have been demonstrated with excellent imaging performance. The MWIR QWIP detector array has demonstrated a noise equivalent differential temperature (NEDT) of 17 mK at a 95 K operating temperature with f/2.5 optics at 300 K background and the LWIR detector array has demonstrated a NEDT of 13 mK at a 70 K operating temperature with the same optical and background conditions as the MWIR detector array after the subtraction of system noise. Both MWIR and LWIR focal planes have shown background limited performance (BLIP) at 90 K and 70 K operating temperatures respectively, with similar optical and background conditions. In addition, we have demonstrated MWIR and LWIR pixel co-registered simultaneously readable dualband QWIP focal plane arrays. In this paper, we will discuss the performance in terms of quantum efficiency, NEDT, uniformity, operability, and modulation transfer functions of the 1024 x 1024 pixel arrays and the progress of dualband QWIP focal plane array development work.

Gunapala, S. D.; Bandara, S. V.; Liu, J. K.; Mumolo, J. M.; Hill, C. J.; Rafol, S. B.; Salazar, D.; Woolaway, J.; LeVan, P. D.; Tidrow, M. Z.

2006-01-01

272

Strong lensing, plane gravitational waves and transient flashes  

E-print Network

Plane-symmetric gravitational waves are considered as gravitational lenses. Numbers of images, frequency shifts, mutual angles, and image distortion parameters are computed exactly in essentially all non-singular plane wave spacetimes. For a fixed observation event in a particular plane wave spacetime, the number of images is found to be the same for almost every source. This number can be any positive integer, including infinity. Wavepackets of finite width are discussed in detail as well as waves which maintain a constant amplitude for all time. Short wavepackets are found to generically produce up to two images of each source which appear (separately) only some time after the wave has passed. They are initially infinitely bright, infinitely blueshifted images of the infinitely distant past. Later, these images become dim and acquire a rapidly-increasing redshift. For sufficiently weak wavepackets, one such "flash" almost always exists. The appearance of a second flash requires that the Ricci tensor inside the wave exceed a certain threshold. This might occur if a gravitational plane wave is sourced by, e.g., a sufficiently strong electromagnetic plane wave.

Abraham I. Harte

2012-10-04

273

The Blue Comet: A Railroad's Astronomical Heritage  

NASA Astrophysics Data System (ADS)

Between 1929 February 21 and 1941 September 27, the Central New Jersey Railroad operated a luxury passenger train between Jersey City and Atlantic City. Named The Blue Comet, the locomotive, tender, and coaches sported a unique royal blue paint scheme designed to evoke images of celestial bodies speeding through space. Inside each car were etched window panes and lampshades featuring stars and comets. And each coach sported the name of a famous comet on its side; these comets were of course named for their discoverers. Some of the astronomers honored in this unique fashion remain famous to this day, or at least their comets do. The names D'Arrest, Barnard, Encke, Faye, Giacobini, Halley, Olbers, Temple, Tuttle, and Westphal are familiar ones. But Biela, Brorsen, deVico, Spitaler, and Winnecke have now largely faded into obscurity; their stories are recounted here. Although more than sixty years have elapsed since its last run, The Blue Comet, perhaps the most famous passenger train in American history, lives on in the memories of millions of passengers and railfans. This famous train returned to the attention of millions of television viewers on the evening of 2007 June 3, in an episode of the HBO series The Sopranos. This work was supported by a faculty development grant from Valdosta State University.

Rumstay, Kenneth S.

2009-01-01

274

Plane wave facing technique for ultrasonic elastography  

NASA Astrophysics Data System (ADS)

A shear wave generation technique which exploits multiple plane waves facing with each other toward their center line is introduced. On this line, ultrasonic waves interfere constructively resulting two planar shear waves that propagate to the opposite directions parallel to the transducer instead of oblique wave from multiple point focused pushes due to the temporal inconsistency of the pushes. One advantage of the plane wave facing technique over an unfocused push beam is that it generates much larger shear waves because it actively takes advantage of constructive interference between waves and, moreover, a larger number of elements can be used without diffusing the beam pattern. Field II simulated intensity maps of the push beams using the proposed method are presented with those of multiple point focusing and unfocusing techniques for comparison. In the simulation, two plane waves are considered for the simplicity, and the number of elements, apodization, and steering angles for facing are varied as parameters. Also, elasticity images of CIRS 049A phantom are presented using the proposed technique with comb-shaped push beams, i.e. multiple push beams are used simultaneously at different locations. L7-4 transducer is used for the simulation and elasticity imaging.

Lee, Mingu; Shim, Hwan; Cheon, Byeong Geun; Jung, Yunsub

2014-03-01

275

TETRANITRO-BLUE TETRAZOLIUM  

E-print Network

In Bacillus subtilis the reduction of potassium tellurite and of tetranitro-blue tetrazolium (TNBT) give comparable results: reduced products appear deposited in particular membranous organelles. For this reason these specialized organelles are considered to be chondrioids (1-3). In the Gram-negative Proteus vulgaris similar membranous structures were never observed by us (4, 5). Therefore it is a challenging problem to investigate the location of the respiratory chain in this organism. With potassium tellurite applied to Proteus (2, 4, 5) in a manner similar to that for Bacillus subtilis (1, 2, 5), we observe deposition of reduced product in a rather restricted cytoplasmic area contiguous to the plasma membrane. In view of modern ideas that enzymes belonging to the oxidative phosphorylation process would be located in elementary particles forming part of the cristae mitochondriales, it was considered essential to determine upon what cell structures in this organism the products of tetranitro-blue tetrazolium reduction are deposited. B R I E F N O T E S 241MATERIALS AND METHODS Proteus vulgaris, a strain obtained from Dr. E. Klieneberger-Nobel, was cultivated under vigorous agitation in Difco hcart infusion broth. To cells in the early logarithmic phase of growth washed with S6rensen buffer was added a solution of 0.05 per cent TNBT in the SSrensen buffer together with either one of the following substrates: 0.5 M sodium succinate, sodium formate, sodium pyruvate, or sodium lactate. The incubation media containing TNBT were supplemerited with 0.004 ~ calcium chloride, and incubation was carried out for 1 hour at room temperature. After incubation the cells were washed in acetate-Vcronal buffer and fixed overnight, in the usual way of Ryter and Kellenberger, and subsequently embedded in Vestopal W. For reasons of comparison some embeddings were made in Epon. Thin sections were cut with glass knives on LKB ultrotomes. The electron micrograpsh were made with a Philips EM 200, using the double condenser lens system and the 25 # objective aperture.

Reduction In; Proteus Vulgaris; W. Leene; Woutera Van Iterson

276

Auditory spatial resolution in horizontal, vertical, and diagonal planes.  

PubMed

Minimum audible angle (MAA) and minimum audible movement angle (MAMA) thresholds were measured for stimuli in horizontal, vertical, and diagonal (60 degrees) planes. A pseudovirtual technique was employed in which signals were recorded through KEMAR's ears and played back to subjects through insert earphones. Thresholds were obtained for wideband, high-pass, and low-pass noises. Only 6 of 20 subjects obtained wideband vertical-plane MAAs less than 10 degrees, and only these 6 subjects were retained for the complete study. For all three filter conditions thresholds were lowest in the horizontal plane, slightly (but significantly) higher in the diagonal plane, and highest for the vertical plane. These results were similar in magnitude and pattern to those reported by Perrott and Saberi [J. Acoust. Soc. Am. 87, 1728-1731 (1990)] and Saberi and Perrott [J. Acoust. Soc. Am. 88, 2639-2644 (1990)], except that these investigators generally found that thresholds for diagonal planes were as good as those for the horizontal plane. The present results are consistent with the hypothesis that diagonal-plane performance is based on independent contributions from a horizontal-plane system (sensitive to interaural differences) and a vertical-plane system (sensitive to pinna-based spectral changes). Measurements of the stimuli recorded through KEMAR indicated that sources presented from diagonal planes can produce larger interaural level differences (ILDs) in certain frequency regions than would be expected based on the horizontal projection of the trajectory. Such frequency-specific ILD cues may underlie the very good performance reported in previous studies for diagonal spatial resolution. Subjects in the present study could apparently not take advantage of these cues in the diagonal-plane condition, possibly because they did not externalize the images to their appropriate positions in space or possibly because of the absence of a patterned visual field. PMID:12942980

Grantham, D Wesley; Hornsby, Benjamin W Y; Erpenbeck, Eric A

2003-08-01

277

21073CAMENABC 5/11 Anthem Blue Cross is the trade name of Blue Cross of California. Anthem Blue Cross and Anthem Blue Cross Life and Health Insurance Company are independent licensees of the Blue Cross Association.  

E-print Network

21073CAMENABC 5/11 Anthem Blue Cross is the trade name of Blue Cross of California. Anthem Blue Cross and Anthem Blue Cross Life and Health Insurance Company are independent licensees of the Blue Cross Association. ® ANTHEM is a registered trademark of Anthem Insurance Companies, Inc. The Blue Cross

Rose, Michael R.

278

Chameleon Graphing: The Coordinate Plane  

NSDL National Science Digital Library

This Web unit introduces the coordinate plane with the help of Sam the Chameleon, who illustrates how to find points on a number line and graph points in the coordinate plane. A link to a Java applet for graphing with Sam is included.

Whitcher, Ursula

2000-01-01

279

Short wavelength infrared hybrid focal plane arrays  

NASA Technical Reports Server (NTRS)

The employment of area focal plane arrays (FPA) has made it possible to obtain second generation infrared imaging systems with high resolution and sensitivity. The Short Wavelength Infrared (SWIR) region (1-2.5 microns) is of importance for imaging objects at high temperature and under conditions of reflected sunlight. The present investigation is concerned with electrooptical characterization results for 32 x 32 SWIR detector arrays and FPAs which are suitable for use in a prototype imaging spectrometer. The employed detector material is Hg(1-x)Cd(x)Te grown by liquid phase epitaxy on a CdTe transparent substrate. Attention is given to details of processing, the design of the detector array, the multiplexer, the fabrication of the hybrid FPA, and aspects of performance.

Vural, K.; Blackwell, J. D.; Marin, E. C.; Edwall, D. D.; Rode, J. P.

1983-01-01

280

Theory of Polar Blue Phases  

E-print Network

In liquid crystals, if flexoelectric couplings between polar order and director gradients are strong enough, the uniform nematic phase can become unstable to formation of a modulated polar phase. Previous theories have predicted two types of modulation, twist-bend and splay-bend; the twist-bend phase has been found in recent experiments. Here, we investigate other types of modulation, using lattice simulations and Landau theory. In addition to twist-bend and splay-bend, we also find polar blue phases, with 2D or 3D modulations of both director and polar order. We compare polar blue phases with chiral blue phases, and discuss opportunities for observing them experimentally.

Shaikh M. Shamid; David W. Allender; Jonathan V. Selinger

2014-05-22

281

Polarization independent blue-phase liquid crystal cylindrical lens with a resistive film  

E-print Network

Polarization independent blue-phase liquid crystal cylindrical lens with a resistive film Yan Li,1); published 7 May 2012 We propose a new electrode design for polarization-independent cylindrical lens using and consequently, its image qual- ity is compromised. Polarization independent blue- phase lens using a curved

Wu, Shin-Tson

282

Design study of the accessible focal plane telescope for shuttle  

NASA Technical Reports Server (NTRS)

The design and cost analysis of an accessible focal plane telescope for Spacelab is presented in blueprints, tables, and graphs. Topics covered include the telescope tube, the telescope mounting, the airlock plus Spacelab module aft plate, the instrument adapter, and the instrument package. The system allows access to the image plane with instrumentation that can be operated by a scientist in a shirt sleeve environment inside a Spacelab module.

1976-01-01

283

Ground plane insulating coating for proximity focused devices  

DOEpatents

A thin layer of alumina (aluminum oxide) is coated onto the ground plane of a microchannel plate (MCP) without covering the pores of the MCP so it does not effect the performance. The coating is sputtered onto the ground plane at a very steep angle. The addition of the thin dielectric coating of alumina greatly improves the spatial resolution of proximity focused image intensifiers using a narrow gap between the phosphor screen and the MCP. With the coating on the ground plane and the same gap the phosphor screen can be ran at 9000 volts, as compared to 3 kV without the coating. 3 figs.

Power, G.D.

1998-07-14

284

Hazards of solar blue light  

SciTech Connect

Short-wavelength visible light (blue light) of the Sun has caused retinal damage in people who have stared fixedly at the Sun without adequate protection. The author quantified the blue-light hazard of the Sun according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines by measuring the spectral radiance of the Sun. The results showed that the exposure limit for blue light can be easily exceeded when people view the Sun and that the solar blue-light hazard generally increases with solar elevation, which is in accordance with a model of the atmospheric extinction of sunlight. Viewing the Sun can be very hazardous and therefore should be avoided except at very low solar elevations.

Okuno, Tsutomu

2008-06-01

285

Laponite blue: dissolving the insoluble.  

PubMed

The neutral organic dye indigo forms an inorganic-organic hybrid material with nanoclays (see picture; blue circles on disks symbolizing indigo, spheres indicating liberated cations) and can thus be transferred into aqueous solution. Solids recovered from these solutions resemble the ancient Maya Blue pigment. The method can also be applied to other hydrophobic species and may open the gate for novel solution chemistry, including photonic and catalytic applications. PMID:22952053

Lezhnina, Marina M; Grewe, Tobias; Stoehr, Hardo; Kynast, Ulrich

2012-10-15

286

iPlane: An Information Plane for Distributed Services  

Microsoft Academic Search

In this paper, we present the design, implementation, and evaluation of iPlane, a scalable service providing accu- rate predictions of Internet path performance for emerg- ing overlay services. Unlike the more common black box latency prediction techniques in use today, iPlane adopts a structural approach and predicts end-to-end path per- formance by composing the performance of measured segments of Internet

Harsha V. Madhyastha; Tomas Isdal; Michael Piatek; Colin Dixon; Thomas E. Anderson; Arvind Krishnamurthy; Arun Venkataramani

2006-01-01

287

MUBs inequivalence and affine planes  

NASA Astrophysics Data System (ADS)

There are fairly large families of unitarily inequivalent complete sets of N + 1 mutually unbiased bases (MUBs) known in {C}N for various prime powers N. The number of such sets is not bounded above by any polynomial as a function of N. While it is standard that there is a superficial similarity between complete sets of MUBs and finite affine planes, there is an intimate relationship between these large families and affine planes. This note briefly summarizes "old" results that do not appear to be well known concerning known families of complete sets of MUBs and their associated planes.

Kantor, W. M.

2012-03-01

288

MUBs inequivalence and affine planes  

E-print Network

There are fairly large families of unitarily inequivalent complete sets of N+1 mutually unbiased bases (MUBs) in C^N for various prime powers N. The number of such sets is not bounded above by any polynomial as a function of N. While it is standard that there is a superficial similarity between complete sets of MUBs and finite affine planes, there is an intimate relationship between these large families and affine planes. This note briefly summarizes "old" results that do not appear to be well-known concerning known families of complete sets of MUBs and their associated planes.

W. K. Kantor

2011-04-18

289

STOCK ASSESSMENT OF THE BLUE CRAB  

E-print Network

STOCK ASSESSMENT OF THE BLUE CRAB IN CHESAPEAKE BAY 2011 #12;2011 Stock assessment for blue crab in Chesapeake Bay iii Executive Summary The blue crab (Callinectes sapidus) is an icon for the Chesapeake Bay region. The commercial fisheries for blue crab in the Bay remain one of the most valuable fishery sectors

290

Press Release No Blue Skies for Mice  

E-print Network

Seite 1/2 Press Release No Blue Skies for Mice Scientists at the University of Tübingen study to make intuitive sense: blue light from the sky is detected by the blue cones, while the greenish light the animals no advantage. "The green cones would `see' the light in the sky just like the blue cones

Tübingen, Universität

291

BLUE WHALE-SIZED MOUTHFULS MAKE FORAGING  

E-print Network

Inside JEB i BLUE WHALE-SIZED MOUTHFULS MAKE FORAGING SUPER EFFICIENT When a blue whale dives from the University of British Columbia, Canada, explains that blue whales may be able to dive, measuring the energetics of blue whale lunges at depth seemed almost impossible until Shadwick and his

Martin, Paul R.

292

The Blue Language1 Michael Klling  

E-print Network

1 The Blue Language1 Michael K�lling School of Computer Science and Software Engineering Monash. The system we are about to discuss is named Blue. Blue is an integrated programming environment and an object. In this issue, we discuss the language aspects of Blue. Next month we will continue the discussion by describing

Kent, University of

293

Realtime extraction of polarimetric information at the focal plane  

NASA Astrophysics Data System (ADS)

Traditional imaging systems focus on converting light's intensity and color property into suitable electronic signals. An important property of light, polarization is ignored with these traditional imaging systems. Polarization vision contains information about the imaged environment, such as surface shapes, curvature and material properties. Real time extraction of polarization properties would further allow synergy with traditional adaptive spatiotemporal image processing techniques for synthetic imaging. Therefore, we have developed an image sensor with real-time polarimetric extraction capability at the focal plane using low power analog circuits. This novel imaging system is the first of its kind to compute Stokes parameters at the focal plane in real-time. In order to fully describe the polarization state of light in nature, three linear polarized projections or two linear polarized projections in combination with the total intensity are required. We have fabricated a two layer micro polarizer array with total thickness of around 20?m. The micro polarizer array is mounted on top of the imaging sensor. The image sensor is composed of a 256 by 256 photo pixel array, noise suppression circuitry and analog processing circuitry for polarimetric computation. The image sensor was fabricated in 0.18? process with 10?m pixel pitch and 75% fill factor. Block-parallel pixel read out is employed in order to compute Stokes parameters on a neighborhood of 2 by 2 pixels. The Stokes parameters are presented together with the noise suppressed intensity image. Experimental data from the polarimetric imaging system is also presented.

Gruev, Viktor; Wu, Kejia; Van der Spiegel, Jan; Engheta, Nader

2006-05-01

294

Tune plane scanning at CESR  

NASA Astrophysics Data System (ADS)

Tune plane scanning, whereby beam parameters such as beam size, lifetime, etc. are measured as a function of horizontal and vertical tune, has proved to be an easy and direct method for observing and identifying resonances at CESR.

Temnykh, A.; Sagan, D.; Welch, J.; Rice, D.

1995-09-01

295

Nicole Hudson Sillerman Center Summer Internship at the Blue Cross Blue Shield of Massachusetts Foundation  

E-print Network

Nicole Hudson Sillerman Center Summer Internship at the Blue Cross Blue Shield of Massachusetts of Philanthropy, I had the privilege of interning at The Blue Cross Blue Shield of Massachusetts Foundation (the Blue Shield of Massachusetts. The Foundation's mission is to expand access to health care services

Snider, Barry B.

296

Water Resource Value Monitoring for Blue Spring and Blue Spring Run, Volusia County, Florida.  

National Technical Information Service (NTIS)

The St. Johns River Water Management District (District) has adopted by rule a minimum flow regime (MFR) for Blue Spring and Blue Spring Run (Blue Spring MFR) in Volusia County, Florida. The Blue Spring MFR will support the protection of the use of Blue S...

2009-01-01

297

Blue Planet Biomes  

NSDL National Science Digital Library

This innovative educational website was created by Elisabeth Benders-Hyde, a science aide at the West Tisbury School in Martha's Vineyard, Massachusetts. The site was originally inspired by a biome project developed by West Tisbury 6th grade teachers Ann and Karl Nelson, and incorporates information generated from independent student research. The site offers great information about the world's biomes including Tundra, Chaparral, Deciduous Forest, Alpine, Rainforest, and more. Biome profiles include general background information with separate sections for biome-specific plants, animals, and climates. This site has an artful lay-out with colorful maps denoting specific biomes, and images of biome landscapes, animals, and plants.

Benders-Hyde, Elisabeth

298

Using Colour for Image Indexing Graham D. Finlayson Bernt Schiele James L. Crowley  

E-print Network

. For example, because images of `beach scenes' typically comprise sea (deep blue), sky (light blue) and sand (beige) a tripartite colour query of Find(light blue, sky blue and beige) should suffice in finding] (a beach viewed under a red dusk sky will result in an image where all the colours are redder than

299

The BlueSky Smoke Modeling Framework: Recent Developments  

NASA Astrophysics Data System (ADS)

BlueSky systems—a set of decision support tools including SmartFire and the BlueSky Framework—aid public policy decision makers and scientific researchers in evaluating the air quality impacts of fires. Smoke and fire managers use BlueSky systems in decisions about prescribed burns and wildland firefighting. Air quality agencies use BlueSky systems to support decisions related to air quality regulations. We will discuss a range of recent improvements to the BlueSky systems, as well as examples of applications and future plans. BlueSky systems have the flexibility to accept basic fire information from virtually any source and can reconcile multiple information sources so that duplication of fire records is eliminated. BlueSky systems currently apply information from (1) the National Oceanic and Atmospheric Administration's (NOAA) Hazard Mapping System (HMS), which represents remotely sensed data from the Moderate Resolution Imaging Spectroradiometer (MODIS), Advanced Very High Resolution Radiometer (AVHRR), and Geostationary Operational Environmental Satellites (GOES); (2) the Monitoring Trends in Burn Severity (MTBS) interagency project, which derives fire perimeters from Landsat 30-meter burn scars; (3) the Geospatial Multi-Agency Coordination Group (GeoMAC), which produces helicopter-flown burn perimeters; and (4) ground-based fire reports, such as the ICS-209 reports managed by the National Wildfire Coordinating Group. Efforts are currently underway to streamline the use of additional ground-based systems, such as states' prescribed burn databases. BlueSky systems were recently modified to address known uncertainties in smoke modeling associated with (1) estimates of biomass consumption derived from sparse fuel moisture data, and (2) models of plume injection heights. Additional sources of remotely sensed data are being applied to address these issues as follows: - The National Aeronautics and Space Administration's (NASA) Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis Real-Time (TMPA-RT) data set is being used to improve dead fuel moisture estimates. - EastFire live fuel moisture estimates, which are derived from NASA's MODIS direct broadcast, are being used to improve live fuel moisture estimates. - NASA's Multi-angle Imaging Spectroradiometer (MISR) stereo heights are being used to improve estimates of plume injection heights. Further, the Fire Location and Modeling of Burning Emissions (FLAMBÉ) model was incorporated into the BlueSky Framework as an alternative means of calculating fire emissions. FLAMBÉ directly estimates emissions on the basis of fire detections and radiance measures from NASA's MODIS and NOAA's GOES satellites. (The authors gratefully acknowledge NASA's Applied Sciences Program [Grant Nos. NN506AB52A and NNX09AV76G)], the USDA Forest Service, and the Joint Fire Science Program for their support.)

Sullivan, D. C.; Larkin, N.; Raffuse, S. M.; Strand, T.; ONeill, S. M.; Leung, F. T.; Qu, J. J.; Hao, X.

2012-12-01

300

Image Processing Chapter 6: Color Image  

E-print Network

of color in image processing is motivated by: 1. Color is important in object recognition 2. Human eyes can of human eye: all colors are seen as variable combinations of 3 primary colors, Red, Green and Blue-emitting · Three primary colors are added and received by the eye as a full-color image 9 Color image processing

Wu, Xiaolin

301

Helicoidal plane of dental occlusion.  

PubMed

A helicoidal plane of postcanine occlusion has been patchily reported in many recent and fossil dentitions of man, and has been suggested as a taxonomic marker distinguishing between the dentitions of Homo and Australopithecines. The present paper describes the helicoidal plane in 19 out of 23 modern human (probably Indian) worn dentitions, in both gracile and robust Australopithecines and in extant anthropoids. It is suggested that tooth wear converts the plane of occlusion present in little-worn teeth, the Monson curve, into a helicoidal plane when 1) the diet is more abrasive, 2) the enamel is thinner and less abrasion resistant, and 3) a longer time separates the eruption of the three molar teeth in a jaw quadrant. A model demonstrates that during the power stroke of a chewing cycle the working side molars move in much the same direction whether the molar occlusal plan follows a Monson curve or a helicoidal plane. The difference is that in the former case the three molars work at the same time while in the latter case they work in sequence from anterior to posterior, thereby concentrating force on one tooth at a time. Because the occlusal plane changes during the life of individuals consuming an abrasive diet, the condition of most anthropoids and hominids, it is argued that the Monson curve has functional significance not because of its influence on occlusal relations and/or jaw movement but because the molar teeth are embedded in bone roughly perpendicular to it, a direction which resists tilting of the teeth during mastication. It is concluded that the helicoidal plane probably has little if any value as a taxonomic marker. PMID:6810702

Osborn, J W

1982-03-01

302

Enhanced Deep Blue aerosol retrieval algorithm: The second generation  

NASA Astrophysics Data System (ADS)

The aerosol products retrieved using the Moderate Resolution Imaging Spectroradiometer (MODIS) collection 5.1 Deep Blue algorithm have provided useful information about aerosol properties over bright-reflecting land surfaces, such as desert, semiarid, and urban regions. However, many components of the C5.1 retrieval algorithm needed to be improved; for example, the use of a static surface database to estimate surface reflectances. This is particularly important over regions of mixed vegetated and nonvegetated surfaces, which may undergo strong seasonal changes in land cover. In order to address this issue, we develop a hybrid approach, which takes advantage of the combination of precalculated surface reflectance database and normalized difference vegetation index in determining the surface reflectance for aerosol retrievals. As a result, the spatial coverage of aerosol data generated by the enhanced Deep Blue algorithm has been extended from the arid and semiarid regions to the entire land areas. In this paper, the changes made in the enhanced Deep Blue algorithm regarding the surface reflectance estimation, aerosol model selection, and cloud screening schemes for producing the MODIS collection 6 aerosol products are discussed. A similar approach has also been applied to the algorithm that generates the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Deep Blue products. Based upon our preliminary results of comparing the enhanced Deep Blue aerosol products with the Aerosol Robotic Network (AERONET) measurements, the expected error of the Deep Blue aerosol optical thickness (AOT) is estimated to be better than 0.05 + 20%. Using 10 AERONET sites with long-term time series, 79% of the best quality Deep Blue AOT values are found to fall within this expected error.

Hsu, N. C.; Jeong, M.-J.; Bettenhausen, C.; Sayer, A. M.; Hansell, R.; Seftor, C. S.; Huang, J.; Tsay, S.-C.

2013-08-01

303

Blue phase liquid crystals stabilized by linear photo-polymerization  

NASA Astrophysics Data System (ADS)

Stabilizing a photopolymer-embedded blue phase liquid crystal precursor with linearly polarized UV light is investigated experimentally. When the UV polarization axis is perpendicular to the stripe electrodes of an in-plane-switching cell, anisotropic polymer networks are formed through the linear photo-polymerization process and the electrostriction effect is suppressed. As a result, the measured hysteresis is dramatically reduced from 6.95% to 0.36% and the response time shortened by ˜2× compared to unpolarized UV exposure. To induce larger anisotropy in polymer networks for mitigating the electrostriction effect, high-intensity linearly polarized UV exposure is preferred.

Xu, Daming; Yuan, Jiamin; Schadt, Martin; Wu, Shin-Tson

2014-08-01

304

Simultaneous measurement of in-plane and out-of-plane displacement derivatives using dual-wavelength digital holographic interferometry.  

PubMed

The paper introduces a method for simultaneously measuring the in-plane and out-of-plane displacement derivatives of a deformed object in digital holographic interferometry. In the proposed method, lasers of different wavelengths are used to simultaneously illuminate the object along various directions such that a unique wavelength is used for a given direction. The holograms formed by multiple reference-object beam pairs of different wavelengths are recorded by a 3-color CCD camera with red, green, and blue channels. Each channel stores the hologram related to the corresponding wavelength and hence for the specific direction. The complex reconstructed interference field is obtained for each wavelength by numerical reconstruction and digital processing of the recorded holograms before and after deformation. Subsequently, the phase derivative is estimated for a given wavelength using two-dimensional pseudo Wigner-Ville distribution and the in-plane and out-of-plane components are obtained from the estimated phase derivatives using the sensitivity vectors of the optical configuration. PMID:22193002

Rajshekhar, Gannavarpu; Gorthi, Sai Siva; Rastogi, Pramod

2011-12-01

305

THE WHIQII SURVEY: METALLICITIES AND SPECTROSCOPIC PROPERTIES OF LUMINOUS COMPACT BLUE GALAXIES  

SciTech Connect

As part of the WIYN High Image Quality Indiana-Irvine (WHIQII) survey, we present 123 spectra of faint emission-line galaxies, selected to focus on intermediate redshift (0.4 approx< z approx< 0.8) galaxies with blue colors that appear physically compact on the sky. The sample includes 15 true Luminous Compact Blue Galaxies (LCBGs) and an additional 27 slightly less extreme emission-line systems. These galaxies represent a highly evolving class that may play an important role in the decline of star formation since z approx 1, but their exact nature and evolutionary pathways remain a mystery. Here, we use emission lines to determine metallicities and ionization parameters, constraining their intrinsic properties and state of star formation. Some LCBG metallicities are consistent with a 'bursting dwarf' scenario, while a substantial fraction of others are not, further confirming that LCBGs are a highly heterogeneous population but are broadly consistent with the intermediate redshift field. In agreement with previous studies, we observe overall evolution in the luminosity-metallicity relation at intermediate redshift. Our sample, and particularly the LCBGs, occupies a region in the empirical R{sub 23}-O{sub 32} plane that differs from luminous local galaxies and is more consistent with dwarf irregulars at the present epoch, suggesting that cosmic 'downsizing' is observable in even the most fundamental parameters that describe star formation. These properties for our sample are also generally consistent with lying between local galaxies and those at high redshift, as expected by this scenario. Surprisingly, our sample exhibits no detectable correlation between compactness and metallicity, strongly suggesting that at these epochs of rapid star formation, the morphology of compact star-forming galaxies is largely transient.

Tollerud, Erik J.; Barton, Elizabeth J.; Cooke, Jeff [Center for Cosmology, Department of Physics and Astronomy, University of California at Irvine, Irvine, CA 92697 (United States); Van Zee, Liese [Astronomy Department, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States)

2010-01-10

306

The blue-collar brain.  

PubMed

Much effort has gone into elucidating control of the body by the brain, less so the role of the body in controlling the brain. This essay develops the idea that the brain does a great deal of work in the service of behavior that is controlled by the body, a blue-collar role compared to the white-collar control exercised by the body. The argument that supports a blue-collar role for the brain is also consistent with recent discoveries clarifying the white-collar role of synergies across the body's tensegrity structure, and the evidence of critical phenomena in brain and behavior. PMID:22719730

Van Orden, Guy; Hollis, Geoff; Wallot, Sebastian

2012-01-01

307

Blue-green upconversion laser  

DOEpatents

A blue-green laser (450-550 nm) uses a host crystal doped with Tm.sup.3+. The Tm.sup.+ is excited through upconversion by a red pumping laser and an IR pumping laser to a state which transitions to a relatively lower energy level through emissions in the blue-green band, e.g., 450.20 nm at 75 K. The exciting laser may be tunable dye lasers or may be solid-state semiconductor laser, e.g., GaAlAs and InGaAlP.

Nguyen, Dinh C. (Los Alamos, NM); Faulkner, George E. (Los Alamos, NM)

1990-01-01

308

Blue light emitting thiogallate phosphor  

DOEpatents

A crystalline blue emitting thiogallate phosphor of the formula RGa.sub.2 S.sub.4 :Ce.sub.x where R is selected from the group consisting of calcium, strontium, barium and zinc, and x is from about 1 to 10 atomic percent, the phosphor characterized as having a crystalline microstructure on the size order of from about 100 .ANG. to about 10,000 .ANG. is provided together with a process of preparing a crystalline blue emitting thiogallate phosphor by depositing on a substrate by CVD and resultant thin film electroluminescent devices including a layer of such deposited phosphor on an ordinary glass substrate.

Dye, Robert C. (Los Alamos, NM); Smith, David C. (Los Alamos, NM); King, Christopher N. (Portland, OR); Tuenge, Richard T. (Hillsboro, OR)

1998-01-01

309

The Blue-Collar Brain  

PubMed Central

Much effort has gone into elucidating control of the body by the brain, less so the role of the body in controlling the brain. This essay develops the idea that the brain does a great deal of work in the service of behavior that is controlled by the body, a blue-collar role compared to the white-collar control exercised by the body. The argument that supports a blue-collar role for the brain is also consistent with recent discoveries clarifying the white-collar role of synergies across the body’s tensegrity structure, and the evidence of critical phenomena in brain and behavior. PMID:22719730

Van Orden, Guy; Hollis, Geoff; Wallot, Sebastian

2012-01-01

310

Blues and the Blues Committee Some historical notes  

E-print Network

ever sporting match between Oxford and Cambridge was at cricket, held on 4 June 1827 of the Cambridge Blue is often posed, but does not have a simple answer. Sport at Oxford and Cambridge, as we now developed their own sports clubs, of course, and these again had their own colours and regalia. The first

Travis, Adrian

311

Progress towards a ``blue'' potassium MOT  

NASA Astrophysics Data System (ADS)

One difficulty when preparing quantum degenerate gases of potassium 40 is the low efficiency of sub-Doppler cooling. In this talk, we discuss how we are attempting to circumvent this problem by implementing a ``blue'' MOT for ^40K on the non-cycling 4S1/2->5P3/2 transition, which has a wavelength of 404.53nm and a decay rate of 1.17MHz. The Doppler temperature should be 27?K, which is a factor of five improvement over the D2 transition at 767nm. This lower temperature would also facilitate in-situ imaging of atoms in optical lattices. The laser setup consists of a cooled diode injection locked to an external cavity diode laser. The master laser is in turn locked to ^39K saturation spectroscopy in a heated vapor cell. The proximity of this 4S-5P transition to the wavelength used in ``Blu-ray'' technology provides a relatively inexpensive source of laser diodes with powers up to 150mW. A dual MOT will be implemented using dichroic mirrors and waveplates for loading and capture with 767nm, followed by a switch to a ``blue'' MOT for late-stage cooling before loading into a magnetic trap. We will also present results on the spectroscopy of the ^40K 5P3/2 hyperfine levels using our setup.

McKay, David; Fine, Dan; Jervis, Dylan; Edge, Graham; Thywissen, Joseph

2011-06-01

312

The epitaxial relationship between M-Plane and c-plane GaN grown on gamma-LiAlO2  

NASA Astrophysics Data System (ADS)

The M-plane and c-plane oriented GaN have been found co-existed in the ?-LiAlO2 substrate grown by molecular beam epitaxy (MBE). Two-step growth with different N/Ga ratios has been used in the experiment at growth temperature 670^oC. By the SEM images, the smooth M-plane surface was observed and the c-plane GaN 3-D structures homogenously spread on it. From the scanning of ?-2? X-ray diffraction pattern, the peaks at 32.295^o and 34.505^o were attributed to the M-plane and c-plane GaN. The microstructure of the samples was investigated by transmission electron microscopic (TEM) study. It was found that the c-plane and M-plane GaN both were oriented from the substrate with the same growth direction and arranged vertically to the substrate with a periodical pattern. The interfaces between the c-plane and M-plane GaN can be confirmed clearly by one or two monolayer in high resolution TEM images. The stacking faults were found at the edge of c-plane side at the interface that released the dislocation between the M- and c-plane GaN. In summary, we found that the M-plane and c-plane GaN can be assembled on ?-LiAlO2 substrate with a clear phase-transition interface.

Wang, Ying-Chieh; Lo, Ikai; Shih, Cheng-Hong; Hu, Chia-Hsueng; Tsai, Cheng-Da; You, Shou-Ting

2013-03-01

313

Red QSOs in the M BH -M* plane  

NASA Astrophysics Data System (ADS)

We present new results on the the MBH-M* relation of X-ray obscured, red QSOs at high redshift (1.2plane compared to a sample of optically blue type-1 QSOs and we find that obscured red QSOs show a constant MBH/M* ratio consistent/slightly higher than the local one but lower than what has been found for blue QSOs. These sources may represent the intermediate phase (blow-out phase) between the major-merger induced starbursts which appear as ULIRGs and SMGs and the optical type-1 blue QSOs which are revealed once the dust and nuclear gas is cleared up.

Bongiorno, Angela

2014-07-01

314

Explosive plane-wave lens  

DOEpatents

An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive.

Marsh, Stanley P. (Los Alamos, NM)

1988-01-01

315

Plane waves as tractor beams  

NASA Astrophysics Data System (ADS)

It is shown that in a large class of systems, plane waves act as tractor beams: i.e., an incident plane wave can exert a pulling force on the scatterer. The underlying physical mechanism for the pulling force is due to the sufficiently strong scattering of the incoming wave into another mode carrying more momentum, in which case excess momentum is created behind the scatterer. This tractor beam or negative radiation pressure (NRP) effect, is found to be generic in systems with multiple scattering channels. In a birefringent medium, electromagnetic plane waves incident on a thin plate exert NRP of the same order of magnitude as optical radiation pressure, while in artificial dielectrics (metamaterials), the magnitude of NRP can even be macroscopic. In two dimensions, we study various scattering situations on vortices, and NRP is shown to occur by the scattering of heavy baryons into light leptons off cosmic strings, and by neutron scattering off vortices in the XY model.

Forgács, Péter; Lukács, Árpád; Roma?czukiewicz, Tomasz

2013-12-01

316

Explosive plane-wave lens  

DOEpatents

An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 3 figs., 3 tabs.

Marsh, S.P.

1987-03-12

317

Explosive plane-wave lens  

DOEpatents

An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 4 figs.

Marsh, S.P.

1988-03-08

318

Submicrometer in-plane integrated surface plasmon cavities.  

PubMed

The optical properties of in-plane integrated surface plasmon polariton (SPP) cavities comprised of a thin film area sandwiched between two one-dimensional Bragg SPP mirrors are investigated numerically and experimentally. We discuss the resonance condition of these cavities, and we analyze in details the physical origin of the dispersion of this resonance. On the basis of numerical results, we show that in-plane SPP cavities can be used to achieve local SPP field enhancement and antireflecting SPP layers. The numerical results are compared to near-field optical images recorded by operating a photon scanning tunneling microscope. From the near-field images recorded over cavities with different sizes at different frequencies, we verify the resonance condition obtained numerically and we measure the quality factor of a submicrometer in-plane integrated SPP cavity. PMID:17439291

Weeber, J-C; Bouhelier, A; Francs, G Colas des; Markey, L; Dereux, A

2007-05-01

319

Space-Plane Spreadsheet Program  

NASA Technical Reports Server (NTRS)

Basic Hypersonic Data and Equations (HYPERDATA) spreadsheet computer program provides data gained from three analyses of performance of space plane. Equations used to perform analyses derived from Newton's second law of physics, derivation included. First analysis is parametric study of some basic factors affecting ability of space plane to reach orbit. Second includes calculation of thickness of spherical fuel tank. Third produces ratio between volume of fuel and total mass for each of various aircraft. HYPERDATA intended for use on Macintosh(R) series computers running Microsoft Excel 3.0.

Mackall, Dale

1993-01-01

320

Numerical investigation of lensless zoomable holographic multiple projections to tilted planes  

E-print Network

This paper numerically investigates the feasibility of lensless zoomable holographic multiple projections to tilted planes. We have already developed lensless zoomable holographic single projection using scaled diffraction, which calculates diffraction between parallel planes with different sampling pitches. The structure of this zoomable holographic projection is very simple because it does not need a lens; however, it only projects a single image to a plane parallel to the hologram. The lensless zoomable holographic projection in this paper is capable of projecting multiple images onto tilted planes simultaneously.

Shimobaba, Tomoyoshi; Kakue, Takashi; Okada, Naohisa; Endo, Yutaka; Hirayam, Ryuji; Hiyama, Daisuke; Hasegawa, Satoki; Nagahama, Yuki; Ito, Tomoyoshi

2014-01-01

321

Benefits of oversampled small pixel focal plane arrays  

NASA Astrophysics Data System (ADS)

Infrared Focal Plane Arrays have been developed with reductions in pixel size below the Nyquist limit imposed by the optical systems Point Spread Function (PSF). These smaller sub diffraction limited pixels allows spatial oversampling of the image. We show that oversampling the PSF allows improved fidelity in imaging, resulting in sensitivity improvements due to pixel correlation, reduced false alarm rates, improved detection ranges, and an improved ability to track closely spaced objects.

Caulfield, John T.; Wilson, Jerry A.; Dhar, Nibir K.

2014-06-01

322

Singing' the Black and Blues  

ERIC Educational Resources Information Center

It is so obvious that the sky is blue in the daytime and black at night, but it took the smartest humans thousands of years of observation, thought, discussion, conjecture, and analysis to finally come up with answers that make scientific sense as to why the sky is these colors. This article discusses light and the scientific research…

Fisher, Diane

2004-01-01

323

Blue Sky and Rayleigh Scattering  

NSDL National Science Digital Library

This site from Georgia State University explains why we see the sky as blue. It describes Rayleigh scattering, which refers to the scattering of light off of the molecules of the air, and Mie scattering, which refers to the scattering of light by larger particles.

Carl R. (Rod) Nave; University, Georgia S.

324

The Taos Blue Lake Ceremony.  

ERIC Educational Resources Information Center

Describes the Blue Lake Ceremony of the Taos Pueblo Indians of New Mexico. Reproduces the 1906 account of the ceremony by anthropologist Matilda Coxe Stevenson and notes modern verification and change. Discusses the importance of this annual August pilgrimage and initiation rite to the preservation of Taos culture. (SV)

Bodine, John J.

1988-01-01

325

Blue Crabs in the Chesapeake  

NSDL National Science Digital Library

This resource is a classroom unit and data activity focusing on juvenile and adult blue crab distribution in the Chesapeake Bay. The pdf includes background on crab biology, anatomy, life cycle, and fisheries. Authentic data tables are provided for in-class analysis and discussion questions guide inquiry.

Clark, Vicki P.; Lawrence, Lisa; Musick, Susanna; Van Montfrans, Jacques

2011-06-13

326

Teaching Sherman Alexie's "Reservation Blues."  

ERIC Educational Resources Information Center

A college teacher discusses his experiences of departing from the established literary canon to teach Sherman Alexie's "Reservation Blues" as part of an upper-level American literature survey class. Students reacted to the novel and its characters, evaluated Alexie's writing techniques, and discussed their personal experiences with Native…

McFarland, Ronald E.

2001-01-01

327

Why is the Sky Blue?  

NSDL National Science Digital Library

This site provides a brief description of the scattering of light rays from the sun in the atmosphere of the Earth. It provides an explanation of why the sky is blue and sunsets are red. The discussion avoids the use of numbers.

328

Current and future trends in infrared focal plane array technology  

Microsoft Academic Search

Infrared focal plane arrays are a critical component in many of the military and civilian applications for advanced imaging systems. Advanced material growth and etching techniques have made possible the fabrication of infrared detectors in various configurations and in a broad range of wavelengths for a variety of applications. In the last decade, many researchers have explored advances in the

Latika Becker

2005-01-01

329

Blue Marble: Remote Characterization of Habitable Planets  

NASA Technical Reports Server (NTRS)

The study of the nature and distribution of habitable environments beyond the Solar System is a key area for Astrobiology research. At the present time, our Earth is the only habitable planet that can be characterized in the same way that we might characterize planets beyond the Solar System. Due to limitations in our current and near-future technology, it is likely that extra-solar planets will be observed as single-pixel objects. To understand this data, we must develop skills in analyzing and interpreting the radiation obtained from a single pixel. These skills must include the study of the time variation of the radiation, and the range of its photometric, spectroscopic and polarimetric properties. In addition, to understand whether we are properly analyzing the single pixel data, we need to compare it with a ground truth of modest resolution images in key spectral bands. This paper discusses the concept for a mission called Blue Marble that would obtain data of the Earth using a combination of spectropolarimetry, spectrophotometry, and selected band imaging. To obtain imagery of the proper resolution, it is desirable to place the Blue Marble spacecraft no closer than the outer region of cis-lunar space. This paper explores a conceptual mission design that takes advantage of low-cost launchers, bus designs and mission elements to provide a cost effective observing platform located at one of the stable Earth-moon Lagrangian points (L4, L5). The mission design allows for the development and use of novel technologies, such as a spinning moon sensor for attitude control, and leverages lessons-learned from previous low-cost spacecraft such as Lunar Prospector to yield a low-risk mission concept.

Woolf, Neville; Lewis, Brian; Chartres, James; Genova, Anthony

2009-01-01

330

Imaging.  

PubMed

Imaging of the musculoskeletal system includes many modalities and is an area that is changing rapidly. Selection of the most accurate techniques and avoidance of duplication are vital to both good patient care and cost containment. PMID:3466135

Wilkinson, R

1986-12-01

331

Explosive Plane-Wave Lens.  

National Technical Information Service (NTIS)

An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than aro...

S. P. Marsh

1987-01-01

332

Plane and parabolic solar panels  

E-print Network

We present a plane and parabolic collector that absorbs radiant energy and transforms it in heat. Therefore we have a panel to heat water. We study how to increment this capture of solar beams onto the panel in order to increase its efficiency in heating water.

J. H. O. Sales; A. T. Suzuki

2009-05-14

333

Plane and parabolic solar panels  

E-print Network

We present a plane and parabolic collector that absorbs radiant energy and transforms it in heat. Therefore we have a panel to heat water. We study how to increment this capture of solar beams onto the panel in order to increase its efficiency in heating water.

Sales, J H O

2009-01-01

334

The plane with parallel coordinates  

Microsoft Academic Search

By means ofParallel Coordinates planar “graphs” of multivariate relations are obtained. Certain properties of the relationship correspond tothe geometrical properties of its graph. On the plane a point ?? line duality with several interesting properties is induced. A new duality betweenbounded and unbounded convex sets and hstars (a generalization of hyperbolas) and between Convex Unions and Intersections is found. This

Alfred Inselberg

1985-01-01

335

An Introduction to Inclined Planes  

NSDL National Science Digital Library

Students are introduced to the concept of simple tools and how they can make difficult or impossible tasks easier. They begin by investigating the properties of inclined planes and how implementing them can reduce the force necessary to lift objects off the ground.

Engineering K-Phd Program

336

Color Correction of Underwater Images for Aquatic Robot Inspection  

E-print Network

the color channels) for each pixel in an image. Prominent blue color of clear ocean water, apart from sky to correct the blue-green monochrome look to bring out the color we know marine life has. For aquatic robot/enhancing the color of underwater images. The term color refers to the red, green and blue values (often called

337

2-Tier In-Plane Motion Correction and Out-of-Plane Motion Filtering for Contrast-Enhanced Ultrasound  

E-print Network

(IPMC). A 2-tier IPMC strategy and adaptive out-of-plane motion filter (OPMF) are proposed to provide B-mode and contrast images. For IPMC, the main reference frame was automatically selected for each-pass filtered TIC within the tumor region-of-interest with low OPMM being the goal. Results for IPMC and OPMF

Kummel, Andrew C.

338

Null-plane invariance of Hamiltonian null-plane dynamics  

Microsoft Academic Search

Relativistic Hamiltonian few-body dynamics [1,2] involves two unitary representations of the Poincare group on the Hilbert space H of physical states, with and without interactions. These two representations, U(Î, a) and Uâ(Î,a), coincide for a kinematic subgroup H. The ''Hamiltonians'' are the generators not in the Lie algebra of the kinematic subgroup. The kinematic subgroup of null-plane dynamics leaves the

Coester

1998-01-01

339

William Blue College of Hospitality Management  

E-print Network

and dinner. William Blue Dining gives our students a hands-on learning experience in a comfortableWilliam Blue College of Hospitality Management UAC 2013­14 Guide 441UAC 2013­14 Guide 441 NORTH SYDNEY CAMPUS CRICOS provider number 00246M postal enquiries William Blue College of Hospitality

New South Wales, University of

340

`blue-sky' science Spending review  

E-print Network

CONTENTS Sea 2 Sky `blue-sky' science Spending review Mighty microbe Blackford investment Talking. Cooling Towers Fiddlers Ferry #12;What are the benefits of `blue-sky' science? At a time where every penny counts, the STFC is making the case that fundamental or blue-sky research yields long term benefits

341

Original article Blue-stain fungi associated  

E-print Network

Original article Blue-stain fungi associated with Tomicus piniperda in Sweden and preliminary to determine the development of blue-staining of sapwood. Fungi were isolated from samples of inner bark and blue-stained sapwood in connection with galleries of T piniperda. Samples were also taken from beetle

Paris-Sud XI, Université de

342

Blue Waters: An Extraordinary Research Capability for  

E-print Network

Blue Waters: An Extraordinary Research Capability for Ad ancing Science & Engineering Frontiers will talk about the new supercomputer Blue Waters and its proposed use by the science and engineering of the University of Illinois at Urbana-Champaign. This system, called Blue Waters, is based on the latest computing

343

Sliding Down an Incline Plane Model  

NSDL National Science Digital Library

The Sliding Down an Incline Plane model shows a stone block is lying on an inclined plane. Initially, the component of gravity along the plane surface, Ft, is compensated by the force of static friction Fsf, which is proportional to the normal to the plane, N. Because the modulus of this force cannot exceed a limit value of ?|N| (? is the static friction coefficient between the block and the plane). When the user increases the slope of the plane by dragging the double arrow at the plane top, Ft ends up being larger than this limit and the block slides down the plane The Sliding Down an Incline Plane model was created using the Easy Java Simulations (Ejs) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_murcia_mech_SlidingDownAnInclinePlane.jar file will run the program if Java is installed.

Franciscouembre

2010-04-16

344

IMAGE Spacecraft Pictures Aurora  

NSDL National Science Digital Library

This NASA site hosts a composite image of the southern lights Aurora over the South Pole. A link enables visitors to view a video of this aurora. The image of the Aurora is overlaid on a NASA âBlue Marbleâ image also captured by satellite. Text describes the distortion of Earthâs magnetic field by the stream of protons and electrons from the sun.

2012-12-24

345

1) Anthem Blue Dental PPO Plus 2) Anthem Blue Dental PPO  

E-print Network

- 35 - 1) Anthem Blue Dental PPO Plus 2) Anthem Blue Dental PPO DENTAL INSURANCE ANTHEM BLUE CROSS AND BLUE SHIELD You may select from two separate dental care plans to meet your individual needs. Premium with comprehensive dental care benefits. However, each plan has special features and a variety of ways to manage your

346

Why is the ocean blue? One of these misconceptions is that the ocean is blue  

E-print Network

Why is the ocean blue? One of these misconceptions is that the ocean is blue because the sky owed its color to the sky, it would be a lighter shade of blue and it would be white on cloudy days transparent not turquoise blue, as it is observed even in indoor pools, where there's no sky to be reflected

Cruz-Pol, Sandra L.

347

The riddle of the blue-straggler stars Die Blauen Nachz uglersterne (blue-straggler  

E-print Network

The riddle of the blue-straggler stars Die Blauen Nachz uglersterne (blue-straggler stars) sind sequence beyond the turn o#11;. These so- called blue-straggler stars (BS) are quite common, they occur systems. Fig. 1 provides an example of an intermediate old open cluster with a rich blue

348

Fast & Furious focal-plane wavefront sensing  

E-print Network

We present two complementary algorithms suitable for using focal-plane measurements to control a wavefront corrector with an extremely high spatial resolution. The algorithms use linear approximations to iteratively minimize the aberrations seen by the focal-plane camera. The first algorithm, Fast & Furious (FF), uses a weak-aberration assumption and pupil symmetries to achieve fast wavefront reconstruction. The second algorithm, an extension to FF, can deal with an arbitrary pupil shape; it uses a Gerchberg-Saxton style error reduction to determine the pupil amplitudes. Simulations and experimental results are shown for a spatial light modulator controlling the wavefront with a resolution of 170 x 170 pixels. The algorithms increase the Strehl ratio from ~0.75 to 0.98-0.99, and the intensity of the scattered light is reduced throughout the whole recorded image of 320 x 320 pixels. The remaining wavefront rms error is estimated to be ~0.15 rad with FF and ~0.10 rad with FF-GS.

Korkiakoski, Visa; Doelman, Niek; Kenworthy, Matthew; Otten, Gilles; Verhaegen, Michel

2014-01-01

349

Fast & Furious focal-plane wavefront sensing.  

PubMed

We present two complementary algorithms suitable for using focal-plane measurements to control a wavefront corrector with an extremely high-spatial resolution. The algorithms use linear approximations to iteratively minimize the aberrations seen by the focal-plane camera. The first algorithm, Fast & Furious (FF), uses a weak-aberration assumption and pupil symmetries to achieve fast wavefront reconstruction. The second algorithm, an extension to FF, can deal with an arbitrary pupil shape; it uses a Gerchberg-Saxton (GS)-style error reduction to determine the pupil amplitudes. Simulations and experimental results are shown for a spatial-light modulator controlling the wavefront with a resolution of 170×170??pixels. The algorithms increase the Strehl ratio from ?0.75 to 0.98-0.99, and the intensity of the scattered light is reduced throughout the whole recorded image of 320×320??pixels. The remaining wavefront rms error is estimated to be ?0.15??rad with FF and ?0.10??rad with FF-GS. PMID:25090079

Korkiakoski, Visa; Keller, Christoph U; Doelman, Niek; Kenworthy, Matthew; Otten, Gilles; Verhaegen, Michel

2014-07-10

350

The blue supergiant Sher 25 and its intriguing hourglass nebula  

Microsoft Academic Search

The blue supergiant Sher 25 is surrounded by an asymmetric, hourglass-shaped\\u000acircumstellar nebula. Its structure and dynamics have been studied previously\\u000athrough high-resolution imaging and spectroscopy, and it appears dynamically\\u000asimilar to the ring structure around SN 1987A. Here we present long-slit\\u000aspectroscopy of the circumstellar nebula around Sher 25, and of the background\\u000anebula of the host cluster NGC

M. A. Hendry; S. J. Smartt; E. D. Skillman; C. J. Evans; C. Trundle; D. J. Lennon; P. A. Crowther; I. Hunter

2008-01-01

351

The blue supergiant Sher 25 and its intriguing hourglass nebula  

Microsoft Academic Search

The blue supergiant Sher25 is surrounded by an asymmetric, hourglass-shaped circumstellar nebula. Its structure and dynamics have been studied previously through high-resolution imaging and spectroscopy, and it appears dynamically similar to the ring structure around SN1987A. Here, we present long-slit spectroscopy of the circumstellar nebula around Sher25, and of the background nebula of the host cluster NGC3603. We perform a

M. A. Hendry; S. J. Smartt; E. D. Skillman; C. J. Evans; C. Trundle; D. J. Lennon; P. A. Crowther; I. Hunter

2008-01-01

352

Identification of polymer stabilized blue-phase liquid crystal display by chromaticity diagram  

NASA Astrophysics Data System (ADS)

We reported an identification method of blue phase liquid crystal (BPLC) display status by using Commission International de l'Éclairage (CIE) chromaticity diagram. The BPLC was injected into in-plane-switch (IPS) cell, polymer stabilized (PS) by ultraviolet cured process and analyzed by luminance colorimeter. The results of CIE chromaticity diagram showed a remarkable turning point when polymer stabilized blue phase liquid crystal II (PSBPLC-II) formed in the IPS cell. A mechanism of CIE chromaticity diagram identify PSBPLC display status was proposed, and we believe this finding will be useful to application and production of PSBPLC display.

Lan, Yi-Fen; Tsai, Cheng-Yeh; Wang, Ling-Yung; Ku, Po-Jen; Huang, Tai-Hsiang; Liu, Chu-Yu; Sugiura, Norio

2012-04-01

353

49 CFR 218.23 - Blue signal display.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Blue signal display. 218.23 Section 218...TRANSPORTATION RAILROAD OPERATING PRACTICES Blue Signal Protection of Workers § 218.23 Blue signal display. (a) Blue signals...

2013-10-01

354

49 CFR 218.23 - Blue signal display.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 2012-10-01 false Blue signal display. 218.23 Section 218...TRANSPORTATION RAILROAD OPERATING PRACTICES Blue Signal Protection of Workers § 218.23 Blue signal display. (a) Blue signals...

2012-10-01

355

Status of Blue Ridge Reservoir  

SciTech Connect

This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Blue Ridge Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports and data available, as well as interview with water resource professionals in various federal, state, and local agencies. Blue Ridge Reservoir is a single-purpose hydropower generating project. When consistent with this primary objective, the reservoir is also operated to benefit secondary objectives including water quality, recreation, fish and aquatic habitat, development of shoreline, aesthetic quality, and other public and private uses that support overall regional economic growth and development. 8 refs., 1 fig.

Not Available

1990-09-01

356

Once in a Blue Moon  

NSDL National Science Digital Library

In this lesson, students will demonstrate an understanding of the moon's features by creating an art or writing project about it. They will learn the concept of a "Blue Moon", which occurs in months with two full moons. They will also understand that the moon is smaller than the Earth, has no light of its own, has no air or water, and has a dusty brown surface marked with craters.

1998-01-01

357

Showcase of Blue Sky Catastrophes  

NASA Astrophysics Data System (ADS)

Let a system of differential equations possess a saddle-node periodic orbit such that every orbit in its unstable manifold is homoclinic, i.e. the unstable manifold is a subset of the (global) stable manifold. We study several bifurcation cases where the splitting of such a homoclinic connection causes the Blue Sky Catastrophe, including the onset of complex dynamics. The birth of an invariant torus or a Klein bottle is also described.

Shilnikov, Leonid Pavlovich; Shilnikov, Andrey L.; Turaev, Dmitry V.

2014-08-01

358

Rooting of blue honeysuckle microshoots  

Microsoft Academic Search

Rooting of axillary shoots of two blue honeysuckle forms, Lonicera caerulea f. caerulea and L. caerulea f. edulis, was studied.\\u000a Both in vitro and ex vitro rooting procedures were used, and the effects of mineral and auxin concentrations of the rooting\\u000a media were tested. Reduced mineral nutrient concentrations of modified MS medium allowed more root elongation but did not\\u000a affect

Saila T. Karhu

1997-01-01

359

Role of in-plane polarizability of the tip in scattering near-field microscopy of a plasmonic nanoparticle.  

PubMed

We report that a pyramid-shaped scanning probe microscopy tip has non-zero polarizability along the in-plane direction (perpendicular to the tip axis, z) at visible frequency. The in-plane polarizability enables the scattering-type scanning near-field optical microscopy (s-SNOM) to measure the in-plane field component around a plasmon-resonant nanoparticle. Because of the non-zero in-plane polarizability, the cross-polarized s-SNOM images may contain contributions from the in-plane field component of an out-of-plane plasmon mode as well as the out-of-plane field component of an in-plane mode. By comparing a scattering model and experimental s-SNOM images, we estimate the polarization anisotropies of pyramid-shaped Si-tips and metal-coated Si-tips. PMID:22513579

Kim, Deok-Soo; Kim, Zee Hwan

2012-04-01

360

Confined Cubic Blue Phases under Shear  

E-print Network

We study the behaviour of confined cubic blue phases under shear flow via lattice Boltzmann simulations. We focus on the two experimentally observed phases, blue phase I and blue phase II. The disinclination network of blue phase II continuously breaks and reforms under shear, leading to an oscillatory stress response in time. The oscillations are only regular for very thin samples. For thicker samples, the shear leads to a "stick-slip" motion of part of the network along the vorticity direction. Blue phase I responds very differently: its defect network undergoes seemingly chaotic rearrangements under shear, irrespective of system size.

O. Henrich; K. Stratford; D. Marenduzzo; P. V. Coveney; M. E. Cates

2011-11-23

361

Confined cubic blue phases under shear.  

PubMed

We study the behaviour of confined cubic blue phases under shear flow via lattice Boltzmann simulations. We focus on the two experimentally observed phases, blue phase I and blue phase II. The disclination network of blue phase II continuously breaks and reforms under shear, leading to an oscillatory stress response in time. The oscillations are only regular for very thin samples. For thicker samples, the shear leads to a 'stick-slip' motion of part of the network along the vorticity direction. Blue phase I responds very differently: its defect network undergoes seemingly chaotic rearrangements under shear, irrespective of system size. PMID:22738991

Henrich, O; Stratford, K; Marenduzzo, D; Coveney, P V; Cates, M E

2012-07-18

362

A Comparison of Blue Light and Caffeine Effects on Cognitive Function and Alertness in Humans  

PubMed Central

The alerting effects of both caffeine and short wavelength (blue) light have been consistently reported. The ability of blue light to enhance alertness and cognitive function via non-image forming neuropathways have been suggested as a non-pharmacological countermeasure for drowsiness across a range of occupational settings. Here we compare and contrast the alerting and psychomotor effects of 240 mg of caffeine and a 1-h dose of ~40 lx blue light in a non-athletic population. Twenty-one healthy subjects performed a computer-based psychomotor vigilance test before and after each of four randomly assigned trial conditions performed on different days: white light/placebo; white light/240 mg caffeine; blue light/placebo; blue light/240 mg caffeine. The Karolinska Sleepiness Scale was used to assess subjective measures of alertness. Both the caffeine only and blue light only conditions enhanced accuracy in a visual reaction test requiring a decision and an additive effect was observed with respect to the fastest reaction times. However, in a test of executive function, where a distraction was included, caffeine exerted a negative effect on accuracy. Furthermore, the blue light only condition consistently outperformed caffeine when both congruent and incongruent distractions were presented. The visual reactions in the absence of a decision or distraction were also enhanced in the blue light only condition and this effect was most prominent in the blue-eyed participants. Overall, blue light and caffeine demonstrated distinct effects on aspects of psychomotor function and have the potential to positively influence a range of settings where cognitive function and alertness are important. Specifically, despite the widespread use of caffeine in competitive sporting environments, the possible impact of blue light has received no research attention. PMID:24282477

Beaven, C. Martyn; Ekstrom, Johan

2013-01-01

363

Platinum blue as an alternative to uranyl acetate for staining in transmission electron microscopy.  

PubMed

This paper introduces an aqueous solution of platinum blue (Pt-blue) as an alternative to uranyl acetate (UA) for staining in transmission electron microscopy (TEM). Pt-blue was prepared from a reaction of cis-dichlorodiamine-platinum (II) (cis-platin) with thymidine. When Pt-blue was dried on a microgrid and observed by TEM it showed a uniform appearance with tiny particles less than 1 nm in diameter. The effect of Pt-blue as an electron stain was then examined not only for positive staining of conventional ultrathin resin sections and counterstaining of post-embedding immuno-electron microscopy but also for negative staining. In ultrathin sections of the rat liver and renal glomerulus, Pt-blue provided good contrast images, especially in double staining combined with a lead stain (Pb). Almost all cell organelles were clearly observed with high contrast in these sections. Glycogen granules in the hepatic parenchymal cells were particularly electron dense in Pt-blue stained sections compared with those treated with UA. In longitudinal and transverse sections of budding influenza A viruses, a specific arrangement of rod-like structures, which correspond to the ribonucleoprotein complexes, was clearly shown in each virion stained with Pt-blue and Pb. When post-embedding immunoelectron microscopy was performed in ultrathin sections of HeLa cells embedded in Lowicryl K4M, the localization of Ki-67 protein was sufficiently detected even after Pt-blue and Pb staining. The present study also revealed that Pt-blue could be used for the negative staining of E. coli, allowing the visualization of a flagellum. These findings indicate that Pt-blue is a useful, safe, and easily obtainable electron stain that is an alternative to UA for TEM preparations. PMID:17558143

Inaga, Sumire; Katsumoto, Tetsuo; Tanaka, Keiichi; Kameie, Toshio; Nakane, Hironobu; Naguro, Tomonori

2007-04-01

364

The Cryptochrome Blue Light Receptors  

PubMed Central

Cryptochromes are photolyase-like blue light receptors originally discovered in Arabidopsis but later found in other plants, microbes, and animals. Arabidopsis has two cryptochromes, CRY1 and CRY2, which mediate primarily blue light inhibition of hypocotyl elongation and photoperiodic control of floral initiation, respectively. In addition, cryptochromes also regulate over a dozen other light responses, including circadian rhythms, tropic growth, stomata opening, guard cell development, root development, bacterial and viral pathogen responses, abiotic stress responses, cell cycles, programmed cell death, apical dominance, fruit and ovule development, seed dormancy, and magnetoreception. Cryptochromes have two domains, the N-terminal PHR (Photolyase-Homologous Region) domain that bind the chromophore FAD (flavin adenine dinucleotide), and the CCE (CRY C-terminal Extension) domain that appears intrinsically unstructured but critical to the function and regulation of cryptochromes. Most cryptochromes accumulate in the nucleus, and they undergo blue light-dependent phosphorylation or ubiquitination. It is hypothesized that photons excite electrons of the flavin molecule, resulting in redox reaction or circular electron shuttle and conformational changes of the photoreceptors. The photoexcited cryptochrome are phosphorylated to adopt an open conformation, which interacts with signaling partner proteins to alter gene expression at both transcriptional and posttranslational levels and consequently the metabolic and developmental programs of plants. PMID:21841916

Yu, Xuhong; Liu, Hongtao; Klejnot, John; Lin, Chentao

2010-01-01

365

Models of Individual Blue Stragglers  

E-print Network

This chapter describes the current state of models of individual blue stragglers. Stellar collisions, binary mergers (or coalescence), and partial or ongoing mass transfer have all been studied in some detail. The products of stellar collisions retain memory of their parent stars and are not fully mixed. Very high initial rotation rates must be reduced by an unknown process to allow the stars to collapse to the main sequence. The more massive collision products have shorter lifetimes than normal stars of the same mass, while products between low mass stars are long-lived and look very much like normal stars of their mass. Mass transfer can result in a merger, or can produce another binary system with a blue straggler and the remnant of the original primary. The products of binary mass transfer cover a larger portion of the colour-magnitude diagram than collision products for two reasons: there are more possible configurations which produce blue stragglers, and there are differing contributions to the blended ...

Sills, Alison

2014-01-01

366

Orbital Space Plane (OSP) Program  

NASA Technical Reports Server (NTRS)

Lockheed Martin has been an active participant in NASA's Space Launch Initiative (SLI) programs over the past several years. SLI, part of NASA's Integrated Space Transportation Plan (ISTP), was restructured in November of 2002 to focus the overall theme of safer, more afford-able space transportation along two paths - the Orbital Space Plane Program and the Next Generation Launch Technology programs. The Orbital Space Plane Program has the goal of providing rescue capability from the International Space Station by 2008 and transfer capability for crew (and limited cargo) by 2012. The Next Generation Launch Technology program is combining research and development efforts from the 2nd Generation Reusable Launch Vehicle (2GRLV) program with cutting-edge, advanced space transportation programs (previously designated 3rd Generation) into one program aimed at enabling safe, reliable, cost-effective reusable launch systems by the middle of the next decade. Lockheed Martin is one of three prime contractors working to bring Orbital Space Plane system concepts to a system definition level of maturity by December of 2003. This paper and presentation will update the international community on the progress of the' OSP program, from an industry perspective, and provide insights into Lockheed Martin's role in enabling the vision of a safer, more affordable means of taking people to and from space.

McKenzie, Patrick M.

2003-01-01

367

Plane-wave fluorescence tomography with adaptive finite elements.  

PubMed

We present three-dimensional fluorescence yield tomography of a tissue phantom in a noncontact reflectance imaging setup. The method employs planar illumination with modulated light and frequency domain fluorescence measurements made on the illumination plane. An adaptive finite-element algorithm is used to handle the ill-posed and computationally demanding inverse image reconstruction problem. Tomographic images of fluorescent targets buried at 1-2 cm depths from the illumination surface demonstrate the feasibility of fluorescence tomography from reflectance tomography in clinically relevant tissue volumes. PMID:16441027

Joshi, Amit; Bangerth, Wolfgang; Hwang, Kildong; Rasmussen, John; Sevick-Muraca, Eva M

2006-01-15

368

Enhanced electroluminescence of a-plane InGaN light emitting diodes grown on oxide-patterned r-plane sapphire substrates.  

PubMed

We report on the new fabrication method of a-plane InGaN light emitting diodes (LEDs) using the epitaxy on patterned insulator on sapphire substrate (EPISS). Cathodoluminescence spectrum of the fully coalesced a-plane GaN template showed that band edge emission intensity of the wing region was four times higher than that of the window region. Threading dislocations and basal stacking faults densities in wing region were ~1×10? cm?² and ~5?10? cm?¹, respectively. Blue-emitting (443.4 nm) a-plane InGaN LED employing EPISS showed the optical power of 3.1 mW and the EL FWHM of 25.2 nm at the injection current of 20 mA. PMID:22109183

Hwang, Sung-Min; Song, Hooyoung; Seo, Yong Gon; Son, Ji-Su; Kim, Jihoon; Baik, Kwang Hyeon

2011-11-01

369

Detection of buried land mines using a dual-band LWIR\\/LWIR QWIP focal plane array  

Microsoft Academic Search

We report on the development and testing of a new dual-band infrared focal plane array (FPA) specifically designed to detect buried land mines. The detector response spectra were tailored to take advantage of the sharp spectral features associated with disturbed soils. The goal was to have a “blue” channel with peak response near 9.2 ?m and a “red” channel with

Arnold Goldberg; Parvez N Uppal; Michael Winn

2003-01-01

370

Redox Processes in the Blue Light Response of Guard Cell Protoplasts of Commelina communis L  

PubMed Central

Guard cell protoplasts from Commelina communis L. illuminated with red light responded to a blue light pulse by an H+ extrusion which lasted for about 10 minutes. This proton extrusion was accompanied by an O2 uptake with a 4H+ to O2 ratio. The response to blue light was nil in darkness without a preillumination period of red light and increased with the duration of the red light illumination until about 40 minutes. However, acidification in response to a pulse of blue light was obtained in darkness when external NADH (1 millimolar) was added to the incubation medium, suggesting that redox equivalents necessary for the expression of the response to blue light in darkness may be supplied via red light. In accordance with this hypothesis, the photosystem II inhibitor 3-(3,4-dichlorophenyl)-1, 1-dimethylurea (10 micromolar) decreased the acidification in response to blue light more efficiently when it was added before red light illumination than before the blue light pulse. In the presence of hexacyanoferrate, the acidification in response to a blue light pulse was partly inhibited (53% of control), suggesting a competition for reducing power between ferricyanide reduction and the response to blue light. ImagesFigure 5 PMID:16668634

Gautier, Hélène; Vavasseur, Alain; Lascève, Gérard; Boudet, Alain M.

1992-01-01

371

Inflation and alternatives with blue tensor spectra  

NASA Astrophysics Data System (ADS)

We study the tilt of the primordial gravitational waves spectrum. A hint of blue tilt is shown from analyzing the BICEP2 and POLARBEAR data. Motivated by this, we explore the possibilities of blue tensor spectra from the very early universe cosmology models, including null energy condition violating inflation, inflation with general initial conditions, and string gas cosmology, etc. For the simplest G-inflation, blue tensor spectrum also implies blue scalar spectrum. In general, the inflation models with blue tensor spectra indicate large non-Gaussianities. On the other hand, string gas cosmology predicts blue tensor spectrum with highly Gaussian fluctuations. If further experiments do confirm the blue tensor spectrum, non-Gaussianity becomes a distinguishing test between inflation and alternatives.

Wang, Yi; Xue, Wei

2014-10-01

372

Inflation and Alternatives with Blue Tensor Spectra  

E-print Network

We study the tilt of the primordial gravitational waves spectrum. A hint of blue tilt is shown from analyzing the BICEP2 and POLARBEAR data. Motivated by this, we explore the possibilities of blue tensor spectra from the very early universe cosmology models, including null energy condition violating inflation, inflation with general initial conditions, and string gas cosmology, etc. For the simplest G-inflation, blue tensor spectrum also implies blue scalar spectrum. In general, the inflation models with blue tensor spectra indicate large non-Gaussianities. On the other hand, string gas cosmology predicts blue tensor spectrum with highly Gaussian fluctuations. If further experiments do confirm the blue tensor spectrum, non-Gaussianity becomes a distinguishing test between inflation and alternatives.

Yi Wang; Wei Xue

2014-03-23

373

Growth pressure dependence of optical and structural properties of a-plane InGaN/GaN multi-quantum wells on r-plane sapphire  

NASA Astrophysics Data System (ADS)

We investigated the influence of growth pressure on the characteristics of a-plane InGaN based MQWs. Nonpolar a-plane GaN based MQW films were directly grown on r-plane sapphire by metalorganic chemical vapor deposition (MOCVD). The growth pressure for the MQWs was varied from 100 mbar to 400 mbar, while keeping other growth parameters constant. The polarity of a-plane InGaN/GaN grown on r-plane sapphire was determined by CBED (convergent-beam electron diffraction) measurements. The blue-shifted PL peak wavelength and decreased FWHM of the PL peak were observed as the growth pressure was increased from 100 mbar to 400 mbar. Meanwhile, the PL peak intensity for MQWs increased as the growth pressure increased. This result was explained by the variation of the wafer surface temperature, which was affected by the growth pressure in spite of being exposed to the same susceptor temperature. The increased growth pressure leads to increased gas conduction and, thereby, the wafer surface temperature increased. For MQWs grown at the same wafer surface temperature, the higher growth pressure led to increased In incorporation in a-plane InGaN/GaN MQWs.

Song, Keun-Man; Kim, Jong-Min; Shin, Chan-Soo; Hwang, Sung-Min; Seo, Yong-Gon; Kong, Bo-Hyun; Cho, Hyung-Koun; Yoon, Dae-Ho

2012-01-01

374

1370 Rev. (3/03) An independent licensee of the Blue Cross and Blue Shield Association. Anthem Blue Cross and Blue Shield is the trade name of Anthem Health Plans of New Hampshire, Inc.  

E-print Network

1370 Rev. (3/03) An independent licensee of the Blue Cross and Blue Shield Association. Anthem Blue Cross and Blue Shield is the trade name of Anthem Health Plans of New Hampshire, Inc. ® Registered marks of the Blue Cross and Blue Shield Association. Request for Certification for a Mentally or Physically

Myers, Lawrence C.

375

Improved wheal detection from skin prick test images  

NASA Astrophysics Data System (ADS)

Skin prick test is a commonly used method for diagnosis of allergic diseases (e.g., pollen allergy, food allergy, etc.) in allergy clinics. The results of this test are erythema and wheal provoked on the skin where the test is applied. The sensitivity of the patient against a specific allergen is determined by the physical size of the wheal, which can be estimated from images captured by digital cameras. Accurate wheal detection from these images is an important step for precise estimation of wheal size. In this paper, we propose a method for improved wheal detection on prick test images captured by digital cameras. Our method operates by first localizing the test region by detecting calibration marks drawn on the skin. The luminance variation across the localized region is eliminated by applying a color transformation from RGB to YCbCr and discarding the luminance channel. We enhance the contrast of the captured images for the purpose of wheal detection by performing principal component analysis on the blue-difference (Cb) and red-difference (Cr) color channels. We finally, perform morphological operations on the contrast enhanced image to detect the wheal on the image plane. Our experiments performed on images acquired from 36 different patients show the efficiency of the proposed method for wheal detection from skin prick test images captured in an uncontrolled environment.

Bulan, Orhan

2014-03-01

376

Performance evaluation of electro-optical focal planes for aerial reconnaissance  

Microsoft Academic Search

The Optical Systems Division of Itek Corporation has developed techniques for analytical and experimental evaluation of image performance that have proven especially well suited to verifying the design of electro-optical focal planes. Analytical techniques used in the design process include computer programs that calculate focal plane signal parameters versus scene and camera system parameters. The results are applied to calibrated

W. J. Abrams

1978-01-01

377

Micro-and Nanoscale Deformation Measurement of Surface and Internal Planes via Digital  

E-print Network

media) of a deforming body. Digital image Experimental Mechanics (2007) 47: 51­62 DOI 10.1007/s11340Micro- and Nanoscale Deformation Measurement of Surface and Internal Planes via Digital Image Mechanics 2007 Abstract The digital image correlation (DIC) tech- nique is successfully applied across

Sottos, Nancy R.

378

Second-Order Design Methods for Definitive Studies of Plane-Symmetric, Two-Mirror Systems.  

National Technical Information Service (NTIS)

In the early stages of optical design, the consideration of low-order imaging properties significantly simplifies the identification of promising configurations. This process is investigated here for plane symmetric systems composed of two off-axis sectio...

B. D. Stone, G. W. Forbes

1994-01-01

379

Application of morphological bit planes in retinal blood vessel extraction.  

PubMed

The appearance of the retinal blood vessels is an important diagnostic indicator of various clinical disorders of the eye and the body. Retinal blood vessels have been shown to provide evidence in terms of change in diameter, branching angles, or tortuosity, as a result of ophthalmic disease. This paper reports the development for an automated method for segmentation of blood vessels in retinal images. A unique combination of methods for retinal blood vessel skeleton detection and multidirectional morphological bit plane slicing is presented to extract the blood vessels from the color retinal images. The skeleton of main vessels is extracted by the application of directional differential operators and then evaluation of combination of derivative signs and average derivative values. Mathematical morphology has been materialized as a proficient technique for quantifying the retinal vasculature in ocular fundus images. A multidirectional top-hat operator with rotating structuring elements is used to emphasize the vessels in a particular direction, and information is extracted using bit plane slicing. An iterative region growing method is applied to integrate the main skeleton and the images resulting from bit plane slicing of vessel direction-dependent morphological filters. The approach is tested on two publicly available databases DRIVE and STARE. Average accuracy achieved by the proposed method is 0.9423 for both the databases with significant values of sensitivity and specificity also; the algorithm outperforms the second human observer in terms of precision of segmented vessel tree. PMID:22832895

Fraz, M M; Basit, A; Barman, S A

2013-04-01

380

Greenâs Functions for a Bimaterial Consisting of Two Orthotropic Quarter Planes Subjected to an Antiplane Force and a Screw Dislocation  

NSDL National Science Digital Library

The image singularity approach is employed to construct the Greenâs function for a quarter plane and a bimaterial that consists of two quarter planes bonded together. The material is orthotropic, and is subjected to an antiplane force f and a screw dislocation with magnitude b. Explicit expressions are obtained for the antiplane forces and screw dislocations that are applied at the image singularities.

Ting, T. C.

2006-11-14

381

Exfoliation of Egyptian Blue and Han Blue, Two Alkali Earth Copper Silicate-based Pigments  

PubMed Central

In a visualized example of the ancient past connecting with modern times, we describe the preparation and exfoliation of CaCuSi4O10 and BaCuSi4O10, the colored components of the historic Egyptian blue and Han blue pigments. The bulk forms of these materials are synthesized by both melt flux and solid-state routes, which provide some control over the crystallite size of the product. The melt flux process is time intensive, but it produces relatively large crystals at lower reaction temperatures. In comparison, the solid-state method is quicker yet requires higher reaction temperatures and yields smaller crystallites. Upon stirring in hot water, CaCuSi4O10 spontaneously exfoliates into monolayer nanosheets, which are characterized by TEM and PXRD. BaCuSi4O10 on the other hand requires ultrasonication in organic solvents to achieve exfoliation. Near infrared imaging illustrates that both the bulk and nanosheet forms of CaCuSi4O10 and BaCuSi4O10 are strong near infrared emitters. Aqueous CaCuSi4O10 and BaCuSi4O10 nanosheet dispersions are useful because they provide a new way to handle, characterize, and process these materials in colloidal form. PMID:24796494

Johnson-McDaniel, Darrah; Salguero, Tina T.

2014-01-01

382

Visual Analysis on Relations between Nouns and Adjectives Using a Large Number of Web Images  

E-print Network

-search with multiple keywords. For example, we obtain a photo showing blue sky and a red car for the query with "blue such as "car" and "sea" and and adjectives re- lated to color such as "red" and "blue" was relatively high AND car". To remove such a photo and to obtain only the pho- tos including blue cars, simultaneous image

Yanai, Keiji

383

Division Plane Orientation in Plant Cells  

Microsoft Academic Search

This review discusses current knowledge on division plane determination in plant cells and how division\\u000a within this plane is executed during cytokinesis. Plants cells are unusual among eukaryotes in that their\\u000a planes of division are established prior to the onset of mitosis. Factors that contribute to the initial\\u000a selection of the division plane include extra-cellular signals, cell geometry and polarity,

Amanda J. Wright; Laurie G. Smith

384

Quantum-Well Infrared Photodetector (QWIP) Focal Plane Assembly  

NASA Technical Reports Server (NTRS)

A paper describes the Thermal Infrared Sensor (TIRS), a QWIP-based instrument intended to supplement the Operational Land Imager (OLI) for the Landsat Data Continuity Mission (LDCM). The TIRS instrument is a far-infrared imager operating in the pushbroom mode with two IR channels: 10.8 and 12 microns. The focal plane will contain three 640x512 QWIP arrays mounted on a silicon substrate. The silicon substrate is a custom-fabricated carrier board with a single layer of aluminum interconnects. The general fabrication process starts with a 4-in. (approx.10-cm) diameter silicon wafer. The wafer is oxidized, a single substrate contact is etched, and aluminum is deposited, patterned, and alloyed. This technology development is aimed at incorporating three large-format infrared detecting arrays based on GaAs QWIP technology onto a common focal plane with precision alignment of all three arrays. This focal plane must survive the rigors of flight qualification and operate at a temperature of 43 K (-230 C) for five years while orbiting the Earth. The challenges presented include ensuring thermal compatibility among all the components, designing and building a compact, somewhat modular system and ensuring alignment to very tight levels. The multi-array focal plane integrated onto a single silicon substrate is a new application of both QWIP array development and silicon wafer scale integration. The Invar-based assembly has been tested to ensure thermal reliability.

Jhabvala, Murzy; Jhabvala, Christine A.; Ewin, Audrey J.; Hess, Larry A.; Hartmann, Thomas M.; La, Anh T.

2012-01-01

385

Optimization of starshades: focal plane versus pupil plane  

E-print Network

We search for the best possible transmission for an external occulter coronagraph that is dedicated to the direct observation of terrestrial exoplanets. We show that better observation conditions are obtained when the flux in the focal plane is minimized in the zone in which the exoplanet is observed, instead of the total flux received by the telescope. We describe the transmission of the occulter as a sum of basis functions. For each element of the basis, we numerically computed the Fresnel diffraction at the aperture of the telescope and the complex amplitude at its focus. The basis functions are circular disks that are linearly apodized over a few centimeters (truncated cones). We complemented the numerical calculation of the Fresnel diffraction for these functions by a comparison with pure circular discs (cylinder) for which an analytical expression, based on a decomposition in Lommel series, is available. The technique of deriving the optimal transmission for a given spectral bandwidth is a classical reg...

Flamary, Rémi

2014-01-01

386

I was six years old when Voyager sent its final images of the solar system. I was enchanted by the dramatic, mysterious blues of Neptune and the icy volcanoes of  

E-print Network

with people who can see beyond the "bubble world" of deadlines and dorm life to work for positive change Voyager spacecraft carried a record titled the Sounds of Earth, filled with music, images, and greetings to learn concepts and do projects that I thought were beyond my grasp. It is beautiful to see so much

Richardson Jr., James E.

387

Eta Carinae: Orientation of The Orbital Plane  

NASA Astrophysics Data System (ADS)

Evidence continues to build that Eta Carinae is a massive binary system with a hidden hot companion in a highly elliptical orbit. We present imaging and spectroscopic evidence that provide clues to the orientation of the orbital plane. The circumstellar ejecta, known as the Homunculus and Little Homunculus, are hourglass-shaped structures, one encapsulated within the other, tilted at about 45 degrees from the sky plane. A disk region lies between the bipolar lobes. Based upon their velocities and proper motions, Weigelt blobs B, C and D, very bright emission clumps 0.1 to 0.3" Northwest from Eta Carinae, lie in the disk. UV flux from the hot companion, Eta Car B, photoexcites the Weigelt blobs. Other clumps form a complete chain around the star, but are not significantly photoexcited. The strontium filament, a 'neutral' emission structure, lies in the same general direction as the Weigelt blobs and exhibits peculiar properties indicative that much mid-UV, but no hydrogen-ionizing radiation impinges on this structure. It is shielded by singly-ionized iron. P Cygni absorptions in Fe II lines, seen directly in line of sight from Eta Carinae, are absent in the stellar light scattered by the Weigelt blobs. Rather than a strong absorption extending to -600 km/s, a low velocity absorption feature extends from -40 to -150 km/s. No absorbing Fe II exists between Eta Carinae and Weigelt D, but the outer reaches of the wind are intercepted in line of sight from Weigelt D to the observer. This indicates that the UV radiation is constrained by the dominating wind of Eta Car A to a small cavity carved out by the weaker wind of Eta Car B. Since the high excitation nebular lines are seen in the Weigelt blobs at most phases, the cavity, and hence the major axis of the highly elliptical orbit, must lie in the general direction of the Weigelt blobs. The evidence is compelling that the orbital major axis of Eta Carinae is projected at -45 degrees position angle on the sky. Moreover the milliarcsecond-scale extended structure of Eta Carinae, recently detected by VLTI, may be evidence of the binary companion in the disk plane, not necessarily of a single star as a prolate spheroid extending along the ejecta polar axis. Observations for this activity were accomplished with HST through the STScI and by funding from the STIS GTO and HST GO programs.

Gull, T. R.; Nielsen, K. E.; Ivarsson, S.; Corcoran, M. F.; Verner, E.; Hillier, J. D.

2005-12-01

388

Modeling Blue Horizontal Branch Stars  

NASA Astrophysics Data System (ADS)

The stars of the Blue Horizontal Branch (BHB) are characterized by having being through most of their evolutionary process and lost part of their external layers, leaving only a thin layer of hydrogen and a burning Helium nucleus. This makes these stars very blue and hot, although old. They are present in many stellar population systems (e.g. stellar clusters and elliptical galaxies), and their presence can induce errors in the age determination of these objects using integrated spectra. The stellar population analysis technique using integrated spectra is a very powerful tool nowadays, however stellar population models do not account for the BHB stars. Because of that, the presence of these stars induces to the determination of younger ages than expected for these systems. In this project we will create synthetic spectra for the BHB stars that can be incorporated to the stellar population models to be used in spectral synthesis. Here we present a study of the atmospheric parameters of these stars that will be used to create the synthetic spectra.

Santos, R. G.; Martins, L. P.

2014-10-01

389

Prussian Blue thin films: electrochemical deposition and characterization  

NASA Astrophysics Data System (ADS)

Prussian Blue thin films Fe4[Fe(CN)6]3 are relevant for many applications such as molecular magnets, electrochromism and electrochemical sensors. In this work, Prussian Blue layers were grown through electrochemical deposition on 50 nm Au coated n-type Si (100) substrates, at room temperature, from electrolyte containing HCl, KCl, FeCl3 and K3[Fe(CN)6]. The layer formation was promoted by scanning sequentially the applied voltage, varying the scan rate and the number of cycles. Emphasis was given to the characterization of the samples with scanning and transmission electron microscopy, X-ray diffraction and atomic force microscopy. Pyramidal grains were typically observed with size increasing with the deposition time. The analysis of the topographic images allowed the determination of important practical parameters as the saturation roughness and correlation length, and scaling regime and exponents.

Pasa, Andre A.; Alamini, Marilia F.; da Silva, Rene C.; Zoldan, Vinícius C.; Isoppo, Eduardo A.; Rodrigues Filho, Ubirajara P.; Klein, Aloísio N.

2010-03-01

390

Demonstration AOTF Imaging Spectrometer  

NASA Technical Reports Server (NTRS)

Spectral images of high quality obtained. Acousto-optical-tunable-filter (AOTF) imaging spectrometer is optical system in which AOTF serves as spectrally dispersive element causing image on final focal plane to be shifted on plane by distance depending on wavelength of light emanating from scene. Useful in several applications involving identification, via characteristic spectras, of substances in observed scenes: examples include prospecting for minerals and detecting chemical pollutants.

Chao, Tien-Hsin; Yu, Jeffrey; Cheng, Li-Jen

1993-01-01

391

Optically tuneable blue phase photonic band gaps  

SciTech Connect

This study investigates an optically switchable band gap of photonic crystal that is based on an azobenzene-doped liquid crystal blue phase. The trans-cis photoisomerization of azobenzene deforms the cubic unit cell of the blue phase and shifts the photonic band gap. The fast back-isomerization of azobenzene was induced by irradiation with different wavelengths light. The crystal structure is verified using Kossel diffraction diagram. An optically addressable blue phase display, based on Bragg reflection from the photonic band gap, is also demonstrated. The tunable ranges are around red, green, and blue wavelengths and exhibit a bright saturated color.

Liu, H.-Y.; Wang, C.-T.; Hsu, C.-Y.; Lin, T.-H. [Department of Photonics, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan (China); Liu, J.-H. [Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China)

2010-03-22

392

Snakes Out of the Plane  

NASA Astrophysics Data System (ADS)

We develop a new computational model of elastic rods, taking into account shear and full rotational dynamics, as well as friction, adhesion, and collision. This model is used to study the movement of snakes in different environments. By applying different muscular activation patterns to the snake, we observe many different patterns of motion, from planar undulation to sudden strikes. Many of the most interesting behaviors involve the snake rising out of the horizontal plane in the vertical direction. Such behaviors include a sand snake sidewinding over the hot desert sand and a cobra rearing up into a defensive striking position. Experimental videos of live snakes are analyzed and compared with computational results. We identify and explain a new form of movement previously unobserved: ``collateral locomotion.''

McCormick, Andrew; Young, Bruce A.; Mahadevan, L.

2012-02-01

393

Broken chiral symmetry on a null plane  

SciTech Connect

On a null-plane (light-front), all effects of spontaneous chiral symmetry breaking are contained in the three Hamiltonians (dynamical Poincaré generators), while the vacuum state is a chiral invariant. This property is used to give a general proof of Goldstone’s theorem on a null-plane. Focusing on null-plane QCD with N degenerate flavors of light quarks, the chiral-symmetry breaking Hamiltonians are obtained, and the role of vacuum condensates is clarified. In particular, the null-plane Gell-Mann–Oakes–Renner formula is derived, and a general prescription is given for mapping all chiral-symmetry breaking QCD condensates to chiral-symmetry conserving null-plane QCD condensates. The utility of the null-plane description lies in the operator algebra that mixes the null-plane Hamiltonians and the chiral symmetry charges. It is demonstrated that in a certain non-trivial limit, the null-plane operator algebra reduces to the symmetry group SU(2N) of the constituent quark model. -- Highlights: •A proof (the first) of Goldstone’s theorem on a null-plane is given. •The puzzle of chiral-symmetry breaking condensates on a null-plane is solved. •The emergence of spin-flavor symmetries in null-plane QCD is demonstrated.

Beane, Silas R., E-mail: silas@physics.unh.edu

2013-10-15

394

Focal plane detectors possible detector technologies for OWL/AIRWATCH  

SciTech Connect

New satellite-born projects OWL and AIRWATCH will need single-photon focal-plane detectors of a million pixels in a design which is optimized to the focusing optics and electronics at acceptable cost. We discuss different phototube possibilities and their pros and cons with crude cost estimates. We conclude that a multichannel-photomultiplier solution is safe. A better compromise may be to adapt a 6 or 9 inch X-ray image intensifier tube or develop a 12 inch image intensifier for detecting individual photons, and adapt the optics to have many mirror modules. The possibility of developing super-large-area phototubes is also discussed.

Flyckt, Esso [Photonis SAS, BP250, F-18106 Brive (France)

1998-06-15

395

Ecology of Blue Straggler Stars  

E-print Network

The existence of blue straggler stars (BSS), which appear younger, hotter, and more massive than their siblings, is at odds with a simple picture of stellar evolution, as such stars should have exhausted their nuclear fuel and evolved long ago to become cooling white dwarfs. As such, BSS could just be some quirks but in fact their understanding requires a deep knowledge of many different areas in astronomy, from stellar evolution through cluster dynamics, from chemical abundances to stellar populations. In November 2012, a workshop on this important topic took place at the ESO Chilean headquarters in Santiago. The many topics covered at this workshop were introduced by very comprehensive invited reviews, providing a unique and insightful view on the field. These reviews have now become chapters of the first ever book on BSS.

Boffin, H M J; Beccari, G

2014-01-01

396

Comparisons of surface vs. volumetric model-based registration methods using single-plane vs. bi-plane fluoroscopy in measuring spinal kinematics.  

PubMed

Several 2D-to-3D image registration methods are available for measuring 3D vertebral motion but their performance has not been evaluated under the same experimental protocol. In this study, four major types of fluoroscopy-to-CT registration methods, with different use of surface vs. volumetric models, and single-plane vs. bi-plane fluoroscopy, were evaluated: STS (surface, single-plane), VTS (volumetric, single-plane), STB (surface, bi-plane) and VTB (volumetric, bi-plane). Two similarity measures were used: 'Contour Difference' for STS and STB and 'Weighted Edge-Matching Score' for VTS and VTB. Two cadaveric porcine cervical spines positioned in a box filled with paraffin and embedded with four radiopaque markers were CT scanned to obtain vertebral models and marker coordinates, and imaged at ten static positions using bi-plane fluoroscopy for subsequent registrations using different methods. The registered vertebral poses were compared to the gold standard poses defined by the marker positions determined using CT and Roentgen stereophotogrammetry analysis. The VTB was found to have the highest precision (translation: 0.4mm; rotation: 0.3°), comparable with the VTS in rotations (0.3°), and the STB in translations (0.6mm). The STS had the lowest precision (translation: 4.1mm; rotation: 2.1°). PMID:24011956

Lin, Cheng-Chung; Lu, Tung-Wu; Wang, Ting-Ming; Hsu, Chao-Yu; Shih, Ting-Fang

2014-02-01

397

In-plane video force microscopy of morphogenesis in epithelia  

NASA Astrophysics Data System (ADS)

Video force microscopy (VFM) is a technique that takes segmented time-lapse images as input and makes least-squares estimates for the cell-edge tensions and cell-internal pressures needed to drive observed changes in cell shape. VFM has previously been used to estimate the cell-level forces that drive invagination during Drosophila gastrulation. Doing so required time-lapse images containing entire cross-sections of the embryo. Here, we extend video force microscopy to in-plane images of epithelia -- including examples in which the images cover only a small region of a larger epithelium. This extension requires imposition of constraints on the average cell-internal pressure and the average stress external to the observed patch. We will demonstrate successful estimation of forces in exact models, as well as anomalous cases that prevent successful force estimation. We will then show applications of this technique for inferring the forces driving Drosophila germband retraction and wound healing.

Hutson, M. Shane; Mashburn, David; Copenhaver, Eric; McCleery, W. Tyler; Veldhuis, Jim; Kim, Steven; Brodland, G. Wayne

2013-03-01

398

Blue Skies, Coffee Creamer, and Rayleigh Scattering  

ERIC Educational Resources Information Center

The first physical explanation of Earths blue sky was fashioned in 1871 by Lord Rayleigh. Many discussions of Rayleigh scattering and approaches to studying it both in and out of the classroom are available. Rayleigh scattering accounts for the blue color of the sky and the orange/red color of the Sun near sunset and sunrise, and a number of…

Liebl, Michael

2010-01-01

399

Ostracoda (Myodocopina) from Bahamian Blue Holes  

E-print Network

an account of the new discoveries in science, and of the changes made from year to year in all branches Myodocopida are reported from eight oceanic blue holes in the vicinity of Exuma Cays and Andros Island ostracodes have been collected in oceanic blue holes, nor have they been reported from shallow open waters

Iliffe, Thomas M.

400

Quirks of dye nomenclature. 1. Evans blue.  

PubMed

The history, origin, identity, chemistry and use of Evans blue dye are described along with the first application to staining by Herbert McLean Evans in 1914. In the 1930s, the dye was marketed under the name, Evans blue dye, which was profoundly more acceptable than the ponderous chemical name. PMID:23957706

Cooksey, C J

2014-02-01

401

Nile Blue derivatives as lysosomotropic photosensitizers  

Microsoft Academic Search

The benzophenoxazines, including several Nile blue analogues, are a unique group of dyes that localize selectively in animal tumors. Chemical modifications of Nile blue A can yield derivatives with high 1O2 quantum yields. These derivatives represent a group of potentially effective photosensitizers for selective phototherapy of malignant tumors. In vitro evaluation of these derivatives has indicated that those with high

Chi-Wei Lin; Janine R. Shulok; S. D. Kirley; Louis Cincotta; James W. Foley

1991-01-01

402

Out-of-plane properties  

NASA Technical Reports Server (NTRS)

This paper summarizes three areas of research which were performed to characterize out-of-plane properties of composite materials. In the first investigation, a series of tests was run to characterize the through-the-thickness tensile strength for a variety of composites that included 2D braids, 2D and 3D weaves, and prepreg tapes. A new test method based on a curved beam was evaluated. Failures were significantly different between the 2D materials and the 3D weaves. The 2D materials delaminated between layers due to out-of-plane tensile stresses while the 3D weaves failed due to the formation of radial cracks between the surface plies caused by high circumferential stresses along the inner radius. The strength of the 2D textile composites did not increase relative to the tapes. Final failure in the 3D weaves was caused by a circumferential crack similar to the 2D materials and occurred at a lower bending moment than in other materials. The early failures in the 3D weaves were caused by radial crack formation rather than a low through-the-thickness strength. The second investigation focused on the development of a standard impact test method to measure impact damage resistance. The only impact tests that currently exist are compression after impact (CAI) tests which incorporate elements of both damage resistance and damage tolerance. A new impact test method is under development which uses a quasi-static indentation (QSI) test to directly measure damage resistance. Damage resistance is quantified in terms of the contact force to produce a unit of damage where a metric for damage may be area in C-scan, depth of residual dent , penetration, damage growth, etc. A final draft of an impact standard that uses a QSI test method will be presented to the ASTM Impact Task Group on impact. In the third investigation, the impact damage resistance behavior of a variety of textile materials was studied using the QSI test method. In this study, the force where large damage initiates was measured and the delamination size as a function of force was determined. The force to initiate large damage was significantly lower in braids and weaves. The delamination diameter - impact forace relationship was quanitfied using a damage resistance parameter, Q(*), which related delamination diameter to imapct force over a range of delamination sizes. Using this Q(*) parameter to rate the materials, the stitched uniweaves, toughened epoxy tapes, and through-the-thickness orthogonal interlock weave were the most damage resistant.

Jackson, Wade C.; Portanova, Marc A.

1995-01-01

403

Out-of-plane properties  

SciTech Connect

This paper summarizes three areas of research which were performed to characterize out-of-plane properties of composite materials. In the first investigation, a series of tests was run to characterize the through-the-thickness tensile strength for a variety of composites that included 2D braids, 2D and 3D weaves, and prepreg tapes. A new test method based on a curved beam was evaluated. Failures were significantly different between the 2D materials and the 3D weaves. The 2D materials delaminated between layers due to out-of-plane tensile stresses while the 3D weaves failed due to the formation of radial cracks between the surface plies caused by high circumferential stresses along the inner radius. The strength of the 2D textile composites did not increase relative to the tapes. Final failure in the 3D weaves was caused by a circumferential crack similar to the 2D materials and occurred at a lower bending moment than in other materials. The early failures in the 3D weaves were caused by radial crack formation rather than a low through-the-thickness strength. The second investigation focused on the development of a standard impact test method to measure impact damage resistance. The only impact tests that currently exist are compression after impact (CAI) tests which incorporate elements of both damage resistance and damage tolerance. A new impact test method is under development which uses a quasi-static indentation (QSI) test to directly measure damage resistance. Damage resistance is quantified in terms of the contact force to produce a unit of damage where a metric for damage may be area in C-scan, depth of residual dent, penetration, damage growth, etc. A final draft of an impact standard that uses a QSI test method will be presented to the ASTM Impact Task Group on impact. In the third investigation, the impact damage resistance behavior of a variety of textile materials was studied using the QSI test method.

Jackson, W.C.; Portanova, M.A.

1995-10-01

404

Blue Marble Matches: Using Earth for Planetary Comparisons  

NSDL National Science Digital Library

This activity is designed to introduce students to planetary geologic features and processes. First, students will use NASA satellite images to identify geologic surface features on the "Blue Marble" (Earth), and will explore the connection between those features and the geologic processes that created them. Using that information, students will then compare and discuss similar features on images from other planets. Included are the following materials: teacher's guide (with reference and resource information), student's guide (with activity sheets), and multiple cards of planetary images. Note that the range of targeted grade levels is quite broad; however, explicit adaptations for younger students are highlighted throughout the teacher's guide. This lesson is part of the Expedition Earth and Beyond Education Program.

405

Featured Molecules: Ascorbic Acid and Methylene Blue  

NASA Astrophysics Data System (ADS)

The WebWare molecules of the month for May are featured in several articles in this issue. "Arsenic: Not So Evil After All?" discusses the pharmaceutical uses of methylene blue and its development as the first synthetic drug used against a specific disease. The JCE Classroom Activity "Out of the Blue" and the article "Greening the Blue Bottle" feature methylene blue and ascorbic acid as two key ingredients in the formulation of the blue bottle. You can also see a colorful example of these two molecules in action on the cover. "Sailing on the 'C': A Vitamin Titration with a Twist" describes an experiment to determine the vitamin C (ascorbic acid) content of citrus fruits and challenges students, as eighteenth-century sea captains, to decide the best fruit to take on a long voyage. Fully manipulable (Chime) versions of these and other molecules are available at Only@JCE Online.

Coleman, William F.; Wildman, Randall J.

2003-05-01

406

Blue Stragglers After the Main Sequence  

E-print Network

We study the post-main sequence evolution of products of collisions between main sequence stars (blue stragglers), with particular interest paid to the horizontal branch and asymptotic giant branch phases. We found that the blue straggler progeny populate the colour-magnitude diagram slightly blueward of the red giant branch and between 0.2 and 1 magnitudes brighter than the horizontal branch. We also found that the lifetimes of collision products on the horizontal branch is consistent with the numbers of so-called "evolved blue straggler stars" (E-BSS) identified by various authors in a number of globular clusters, and is almost independent of mass or initial composition profile. The observed ratio of the number of E-BSS to blue stragglers points to a main sequence lifetime for blue stragglers of approximately 1-2 Gyr on average.

Alison Sills; Amanda Karakas; John Lattanzio

2008-11-18

407

Mosaic near-infrared focal plane array  

NASA Astrophysics Data System (ADS)

To built a 3K X 3K pixel near-IR FPA, we have made a package and a multi-chip module for Mitsubishi 1040 X 1040 PtSi CSD, which is one of the largest SWIR FPAs. Mosaicing demands smallest gaps between chips to achieve a large fill-factor and controlled flatness to fit a camera focal plane. The package of 52-pin half-pitch PGA has been designed to be smaller than the bear chip. After the chip is glued on the package and wire-bonded, nine packages with the chip are arrayed in three by three on a multi chip module (MCM) of 6 cm X 6 cm area. The fill-factor of the imaging area is 89 percent. The package and MCM are made of AlN ceramic of high thermal conductivity. MCM, therefore, plays a role of an efficient heat sink. The surface of the package, with which the chip is in contact, has been polished with accurate flatness as well as MCM. As the result, the height of nine chips built on MCM are uniform within approximately 20 micrometers in 6 cm X 6 cm area. The mosaic array will be equipped in a near-IR camera for astronomical observations of a wide field view.

Ichikawa, Takashi; Itoh, Nobunari; Yanagisawa, Kenshi; Asai, Kenichirou; Shiraishi, Tadashi; Kimata, Masafumi

1998-08-01

408

ORFEUS focal plane instrumentation: The Berkeley spectrometer  

NASA Technical Reports Server (NTRS)

A spectrograph for the ORFEUS mission that incorporates four varied line-space, spherically figured diffraction gratings was designed. The ORFEUS, a 1-m normal incidence telescope is equipped with 2 focal plane spectrographs. The Berkeley spectrograph was developed with an optimizing raytracing computer code. Each grating accepts the light from 20 percent of the aperture of the telescope primary mirror and has a unique set of characteristics to cover a sub-bandpass within the 390 to 1200 A spectral range. Two photon-counting detectors incorporating a time delay readout system are used to record the spectra from all four gratings simultaneously. The nominal design achieves a spectral resolution (FWHM) in excess of 5500 at all wavelengths within the bandpass. The resolution is limited primarily by the detector spatial resolution. The 1 sigma astigmatism of this design varies between 13 and 150 micrometer on the same focal surface. An independent, direct imaging system tracks the drift of the target within the spectrometer aperture and allows measurement of the misalignment between the telescope optical axis and that of the external star tracker. The resolution and astigmatism achievable with this design are superior to those of a standard Rowland spectrograph designed with the same constraints.

Hurwitz, Mark; Bowyer, Stuart

1988-01-01

409

Chandra Multi-wavelength Plane Survey  

NASA Astrophysics Data System (ADS)

The ChaMPlane Survey is designed to investigate the nature of the serendipitous X-ray point sources discovered by the Chandra X-ray Observatory, with its unprecedented spatial resolution, in the galactic plane. This multi-wavelength survey includes data from the Chandra archive and our own 840ks Chandra observations near the galactic center, as well as optical and infrared images and spectra we obtained from the Gemini-S, CTIO-4m, KPNO-4m, Magellan, MMT, WIYN and FLWO-1.5m. Its science goals are: 1) to determine the space density of faint accretion-powered binaries, mainly accreting white dwarfs in cataclysmic variables (CVs) and neutron stars or black holes in low-mass X-ray binaries in quiescence (qLMXBs) in the Galaxy; 2) to measure the Be High-Mass X-ray Binary (BeHMXB) density; and 3) to study the population of stellar coronal X-ray sources. We report our findings and summarize selected highlights from this legacy survey.

Zhao, Ping; Grindlay, Jonathan; Hong, Jaesub; Servillat, Mathieu; Van den Berg, Maureen

410

NuSTAR Galactic Plane Survey Program  

NASA Astrophysics Data System (ADS)

The NuSTAR Galactic Plane Survey program consists of several deep surveys and dedicated pointing observations. The survey of a 2x0.8 degree field near Sgr A* should detect hundreds of the sources uncovered by Chandra and help identify their nature by spectroscopy and timing analysis. A similar survey of the Norma region will be performed for comparative population studies. An observation of the Limiting Window, which holds a possible new class of CVs, will yield information on their nature. With NuSTAR's superb hard X-ray sensitivity, these surveys will detect and map the low energy extension of the diffuse gamma-ray background observed by INTEGRAL. NuSTAR will observe Sgr A*, in coordination with Chandra and other observatories, to search for hard X-ray flaring, and provide an image of the central few tens of parsecs of the Galaxy with more than an order of magnitude better sensitivity than INTEGRAL. NuSTAR plans to observe the G2 molecular cloud's infall to Sgr A* in the spring of 2013. NuSTAR will spatially resolve the hard X-ray emission in the molecular cloud Sgr B2. In addition, the 2x0.8 degree field survey will observe other giant molecular clouds such as Sgr A, B1 and C to help us understand their X-ray emission possibly due to a giant flare from Sgr A* in the past.

Mori, Kaya; Barriere, N.; Bauer, F. E.; Boggs, S. E.; Craig, W.; Christensen, F.; Dufour, F.; Gotthelf, E. V.; Grindlay, J. E.; Hailey, C. J.; Harrison, F.; Helfand, D. J.; Hong, J.; Hornstrup, A.; Jakobsen, S.; Kaspi, V.; Krivonos, R.; Madsen, K.; Natalucci, L.; Perez, K.; Smith, D. M.; Stern, D.; Tomsick, J.; Zhang, S.; Zhang, W.; NuSTAR Team

2013-01-01

411

A Statistical Learning-Based Method for Color Correction of Underwater Images  

E-print Network

) for each pixel in an image. Prominent blue color of clear ocean water, apart from sky reflection, is due a challenge when trying to correct the blue-green monochrome shift to bring out the color visible under full images. The term color refers to #12;the red, green and blue values (often called the color channels

412

Focal plane infrared readout circuit  

NASA Technical Reports Server (NTRS)

An infrared imager, such as a spectrometer, includes multiple infrared photodetectors and readout circuits for reading out signals from the photodetectors. Each readout circuit includes a buffered direct injection input circuit including a differential amplifier with active feedback provided through an injection transistor. The differential amplifier includes a pair of input transistors, a pair of cascode transistors and a current mirror load. Photocurrent from a photodetector can be injected onto an integration capacitor in the readout circuit with high injection efficiency at high speed. A high speed, low noise, wide dynamic range linear infrared multiplexer array for reading out infrared detectors with large capacitances can be achieved even when short exposure times are used. The effect of image lag can be reduced.

Pain, Bedabrata (Inventor)

2002-01-01

413

3-facial colouring of plane graphs  

Microsoft Academic Search

A plane graph is l-facially k-colourable if its vertices can be coloured with\\u000ak colours such that any two distinct vertices on a facial segment of length at\\u000amost l are coloured differently. We prove that every plane graph is 3-facially\\u000a11-colourable. As a consequence, we derive that every 2-connected plane graph\\u000awith maximum face-size at most 7 is cyclically

Frédéric Havet; Jean-Sébastien Sereni; Riste Skrekovski

2006-01-01

414

1. GENERAL VIEW OF ENTRANCE TO BLUE RIDGE TUNNEL (LEFT) ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. GENERAL VIEW OF ENTRANCE TO BLUE RIDGE TUNNEL (LEFT) FROM SOUTHEAST. ORIGINAL BLUE RIDGE R.R. (CROZET) TUNNEL IS VISIBLE AT RIGHT. - Chesapeake & Ohio Railroad, Blue Ridge Tunnel, Highway 250 at Rockfish Gap, Afton, Nelson County, VA

415

7 CFR 1217.2 - Blue Ribbon Commission or BRC.  

... 10 2014-01-01 2014-01-01 false Blue Ribbon Commission or BRC. 1217.2 Section...Industry Information Order Definitions § 1217.2 Blue Ribbon Commission or BRC. Blue Ribbon Commission or BRC means the...

2014-01-01

416

7 CFR 1217.2 - Blue Ribbon Commission or BRC.  

Code of Federal Regulations, 2013 CFR

... 10 2013-01-01 2013-01-01 false Blue Ribbon Commission or BRC. 1217.2 Section...Industry Information Order Definitions § 1217.2 Blue Ribbon Commission or BRC. Blue Ribbon Commission or BRC means the...

2013-01-01

417

7 CFR 1217.2 - Blue Ribbon Commission or BRC.  

Code of Federal Regulations, 2012 CFR

... 10 2012-01-01 2012-01-01 false Blue Ribbon Commission or BRC. 1217.2 Section...Industry Information Order Definitions § 1217.2 Blue Ribbon Commission or BRC. Blue Ribbon Commission or BRC means the...

2012-01-01

418

Autonomous real-time interventional scan plane control with a 3-d shape-sensing needle.  

PubMed

This study demonstrates real-time scan plane control dependent on three-dimensional needle bending, as measured from magnetic resonance imaging (MRI)-compatible optical strain sensors. A biopsy needle with embedded fiber Bragg grating (FBG) sensors to measure surface strains is used to estimate its full 3-D shape and control the imaging plane of an MR scanner in real-time, based on the needle's estimated profile. The needle and scanner coordinate frames are registered to each other via miniature radio-frequency (RF) tracking coils, and the scan planes autonomously track the needle as it is deflected, keeping its tip in view. A 3-D needle annotation is superimposed over MR-images presented in a 3-D environment with the scanner's frame of reference. Scan planes calculated based on the FBG sensors successfully follow the tip of the needle. Experiments using the FBG sensors and RF coils to track the needle shape and location in real-time had an average root mean square error of 4.2 mm when comparing the estimated shape to the needle profile as seen in high resolution MR images. This positional variance is less than the image artifact caused by the needle in high resolution SPGR (spoiled gradient recalled) images. Optical fiber strain sensors can estimate a needle's profile in real-time and be used for MRI scan plane control to potentially enable faster and more accurate physician response. PMID:24968093

Elayaperumal, Santhi; Plata, Juan Camilo; Holbrook, Andrew B; Park, Yong-Lae; Pauly, Kim Butts; Daniel, Bruce L; Cutkosky, Mark R

2014-11-01

419

Orange a-plane InGaN/GaN light-emitting diodes grown on r-plane sapphire substrates.  

PubMed

We report on orange a-plane light-emitting diodes (LEDs) with InGaN single quantum well (SQW) grown on r-plane sapphire substrates by metal organic chemical vapor deposition (MOCVD). The peak wavelength and the full-width at half maximum (FWHM) at a drive current of 20mA were 612.2 nm and 72 nm, respectively. The device demonstrated a blue shift in emission wavelength from 614.6 nm at 10 mA to 607.5 nm at 100 mA, representing a net shift of 7.1 nm over a 90 mA range, which is the longest wavelength compared with reported values in nonpolar LEDs. The polarization ratio values obtained from the orange LED varied between 0.36 and 0.44 from 10 to 100mA and a weak dependence of the polarization ratio on the injection current was observed. PMID:21747444

Seo, Yong Gon; Baik, Kwang Hyeon; Song, Hooyoung; Son, Ji-Su; Oh, Kyunghwan; Hwang, Sung-Min

2011-07-01

420

typical introduction to geometrical optics treats plane and spherical mirrors. At first  

E-print Network

are the real image of an object (outside the focal length) reflected in a concave spherical mirror and the virtual image of an object reflected in a plane mirror. A concave cylin- drical mirror has a circular- duced both before and behind a concave cylindrical mirror.3 He also speculated on how this extreme astig

DeWeerd, Alan

421

The ring nebula around the blue supergiant SBW1: pre-explosion snapshot of an SN 1987A twin  

NASA Astrophysics Data System (ADS)

SBW1 is a B-type supergiant surrounded by a ring nebula that is a nearby twin of SN 1987A's progenitor and its circumstellar ring. We present images and spectra of SBW1 obtained with the Hubble Space Telescope (HST), the Spitzer Space Telescope and Gemini South. HST images of SBW1 do not exhibit long Rayleigh-Taylor (RT) fingers, which are presumed to cause the `hotspots' in the SN 1987A ring when impacted by the blast wave, but instead show a geometrically thin (?R/R ? 0.05) clumpy ring. The radial mass distribution and size scales of inhomogeneities in SBW1's ring closely resemble those in the SN 1987A ring, but the more complete disc expected to reside at the base of the RT fingers is absent in SBW1. This structure may explain why portions of the SN 1987A ring between the hotspots have not yet brightened, more than 15 years after the first hotspots appeared. The model we suggest does not require a fast wind colliding with a previous red supergiant wind, because a slowly expanding equatorial ring may be ejected by a rotating blue supergiant star or in a close binary system. More surprisingly, high-resolution images of SBW1 also reveal diffuse emission filling the interior of the ring seen in H? and in thermal-infrared (IR) emission; ˜190 K dust dominates the 8-20 ?m luminosity (but contains only 10-5 M? of dust). Cooler (˜85 K) dust resides in the equatorial ring itself (and has a dust mass of at least 5 × 10-3 M?). Diffuse emission extends inward to ˜1 arcsec from the central star, where a paucity of H? and IR emission suggests an inner hole excavated by the B-supergiant wind. We propose that diffuse emission inside the ring arises from an ionized flow of material photoevaporated from the dense ring, and its pressure prevents the B-supergiant wind from advancing in the equatorial plane. This inner emission could correspond to a structure hypothesized to reside around Sk-69°202 that was never directly detected. If this interpretation is correct, it would suggest that photoionization can play an important dynamical role in shaping the ring nebula, and we speculate that this might help explain the origin of the polar rings around SN 1987A. In effect, the photoevaporative flow shields the outer bipolar nebula at low latitudes, whereas the blue supergiant wind expands freely out the poles and clears away the polar caps of the nebula; the polar rings reside at the intersection of these two zones.

Smith, Nathan; Arnett, W. David; Bally, John; Ginsburg, Adam; Filippenko, Alexei V.

2013-02-01

422

The lizard celestial compass detects linearly polarized light in the blue.  

PubMed

The present study first examined whether ruin lizards, Podarcis sicula, are able to orientate using plane-polarized light produced by an LCD screen. Ruin lizards were trained and tested indoors, inside a hexagonal Morris water maze positioned under an LCD screen producing white polarized light with a single E-vector, which provided an axial cue. White polarized light did not include wavelengths in the UV. Lizards orientated correctly either when tested with E-vector parallel to the training axis or after 90 deg rotation of the E-vector direction, thus validating the apparatus. Further experiments examined whether there is a preferential region of the light spectrum to perceive the E-vector direction of polarized light. For this purpose, lizards reaching learning criteria under white polarized light were subdivided into four experimental groups. Each group was tested for orientation under a different spectrum of plane-polarized light (red, green, cyan and blue) with equalized photon flux density. Lizards tested under blue polarized light orientated correctly, whereas lizards tested under red polarized light were completely disoriented. Green polarized light was barely discernible by lizards, and thus insufficient for a correct functioning of their compass. When exposed to cyan polarized light, lizard orientation performances were optimal, indistinguishable from lizards detecting blue polarized light. Overall, the present results demonstrate that perception of linear polarization in the blue is necessary - and sufficient - for a proper functioning of the sky polarization compass of ruin lizards. This may be adaptively important, as detection of polarized light in the blue improves functioning of the polarization compass under cloudy skies, i.e. when the alternative celestial compass based on detection of the sun disk is rendered useless because the sun is obscured by clouds. PMID:22693032

Beltrami, Giulia; Parretta, Antonio; Petrucci, Ferruccio; Buttini, Paola; Bertolucci, Cristiano; Foà, Augusto

2012-09-15

423

Spitzer observations of a circumstellar nebula around the candidate luminous blue variable MWC 930  

NASA Astrophysics Data System (ADS)

Context. The source MWC 930 is a star just ~2° above the Galactic plane whose nature is not clear and has not been studied in detail so far. While a post-asymptotic giant branch classification was proposed in the past, studies of its optical spectrum and photometry pointed toward strong variability, therefore, the object was reclassified as a luminous blue variable (LBV) candidate. Aims: The LBVs typically undergo phases of strong mass loss in the form of eruptions that can create shells of ejecta around the star. Our goal is to search for the presence of such a circumstellar nebula in MWC 930 and investigate its properties. Methods: To do so, we make use of space-based infrared data from our Spitzer campaign performed with the InfraRed Array Camera (IRAC) and the InfraRed Spectrograph (IRS), as well as data from optical and infrared (IR) surveys. Results: In our Spitzer images, we clearly detect an extended shell around MWC 930 at wavelengths longer than 5 ?m. The mid-infrared spectrum is dominated by the central star and mostly shows forbidden lines of [FeII] with an underlying continuum that decreases with wavelengths up to ~15 ?m and then inverts its slope, displaying a second peak around 60 ?m, which is evidence of cold dust grains formed in a past eruption. By modeling the spectral energy distribution, we identify two central components, beside the star and the outer shell. These extra sources of radiation are interpreted as material close to the central star, which may be due to a recent ejection. Features of C-bearing molecules or grains are not detected.

Cerrigone, L.; Umana, G.; Buemi, C. S.; Hora, J. L.; Trigilio, C.; Leto, P.; Hart, A.

2014-02-01

424

47 CFR 73.160 - Vertical plane radiation characteristics, f(?).  

Code of Federal Regulations, 2012 CFR

...to the horizontal plane. The vertical angle, represented as ?...the horizontal plane. The vertical plane radiation characteristic...computing radiation in the vertical plane, unless the applicant...formula for a particular type of antenna. If a special formula...

2012-10-01

425

47 CFR 73.160 - Vertical plane radiation characteristics, f(?).  

Code of Federal Regulations, 2010 CFR

...to the horizontal plane. The vertical angle, represented as ?...the horizontal plane. The vertical plane radiation characteristic...computing radiation in the vertical plane, unless the applicant...formula for a particular type of antenna. If a special formula...

2010-10-01

426

47 CFR 73.160 - Vertical plane radiation characteristics, f(?).  

Code of Federal Regulations, 2011 CFR

...to the horizontal plane. The vertical angle, represented as ?...the horizontal plane. The vertical plane radiation characteristic...computing radiation in the vertical plane, unless the applicant...formula for a particular type of antenna. If a special formula...

2011-10-01

427

Methylene blue and Alzheimer's disease.  

PubMed

The relationship between methylene blue (MB) and Alzheimer's disease (AD) has recently attracted increasing scientific attention since it has been suggested that MB may slow down the progression of this disease. In fact, MB, in addition to its well characterized inhibitory actions on the cGMP pathway, affects numerous cellular and molecular events closely related to the progression of AD. Currently, MB has been shown to attenuate the formations of amyloid plaques and neurofibrillary tangles, and to partially repair impairments in mitochondrial function and cellular metabolism. Furthermore, various neurotransmitter systems (cholinergic, serotonergic and glutamatergic), believed to play important roles in the pathogenesis of AD and other cognitive disorders, are also influenced by MB. Recent studies suggest that the combination of diverse actions of MB on these cellular functions is likely to mediate potential beneficial effects of MB. This has lead to attempts to develop novel MB-based treatment modalities for AD. In this review article, actions of MB on neurotransmitter systems and multiple cellular and molecular targets are summarized with regard to their relevance to AD. PMID:19433072

Oz, Murat; Lorke, Dietrich E; Petroianu, George A

2009-10-15

428

ECLAIRs detection plane: current state of development  

NASA Astrophysics Data System (ADS)

ECLAIRs, a 2-D coded-mask imaging camera on-board the Sino-French SVOM space mission, will detect and locate Gamma-ray bursts (GRBs) in near real time in the 4-150 keV energy band. The design of ECLAIRs has been mainly driven by the objective of achieving a low-energy threshold of 4 keV, unprecedented for this type of instrument. The detection plane is an assembly of 6400 Schottky CdTe semiconductor detectors of size 4x4x1 mm3 organized on elementary hybrid matrices of 4x8 detectors. The detectors will be polarized from -300V to -500V and operated at -20°C to reduce both the leakage current and the polarization effect induced by the Schottky contact. The remarkable low-energy threshold homogeneity required for the detection plane has been achieved thanks to: i) an extensive characterization and selection of the detectors, ii) the development of a specific low-noise 32-channel ASIC, iii) the realization of an innovative hybrid module composed of a thick film ceramic (holding 32 CdTe detectors with their high voltage grid), associated to an HTCC ceramic (housing the ASIC chip within an hermetic enclosure). In this paper, we start describing a complete hybrid matrix, and then the manufacturing of a first set of 50 matrices (representing 1600 detectors, i.e. a quarter of ECLAIRs detector's array). We show how this manufacturing allowed to validate the different technologies used for this hybridization, as well as the industrialization processes. During this phase, we systematically measured the leakage current on Detector Ceramics after an outgassing, and the Equivalent Noise Charge (ENC) for each of the 32 channels on ASIC Ceramics, in order to optimize the coupling of the two ceramics. Finally, we performed on each hybrid module, spectral measurements at -20°C in our vacuum chamber, using several calibrated radioactive sources (241Am and 55Fe), to check the performance homogeneity of the 50 modules. The results demonstrated that the 32-detector hybrid matrices presented homogeneous spectral properties and that a lowenergy threshold of 4 keV for each detector could be reached. In conclusion, our hybrid module has obtained the performance required at the SVOM mission level and successfully withstood the space environment tests (TRL 6/7). This development phase has given us the opportunity to build a detector's array prototype (Engineering Model) equipped with 50 hybrid modules. Thanks to this prototype we are in the process of validating a complete detection chain (from the detectors to the backend electronics) and checking the performance. In addition it enables us to consolidate the instrument's mechanical and thermal design, and to write preliminary versions of the quality procedures required for integration, functional tests and calibration steps. At the end of this prototype development and testing, we will be ready to start the detailed design of the detection plane Flight Model.

Lacombe, K.; Pons, R.; Amoros, C.; Atteia, J.-L.; Barret, D.; Billot, M.; Bordon, S.; Cordier, B.; Gevin, O.; Godet, O.; Gonzalez, F.; Houret, B.; Mercier, K.; Mandrou, P.; Marty, W.; Nasser, G.; Rambaud, D.; Ramon, P.; Rouaix, G.; Waegebaert, V.

2014-07-01

429

High operating temperature interband cascade focal plane arrays  

NASA Astrophysics Data System (ADS)

In this paper, we report the initial demonstration of mid-infrared interband cascade (IC) photodetector focal plane arrays with multiple-stage/junction design. The merits of IC photodetectors include low noise and efficient photocarrier extraction, even for zero-bias operation. By adopting enhanced electron barrier design and a total absorber thickness of 0.7 ?m, the 5-stage IC detectors show very low dark current (1.10 × 10-7 A/cm2 at -5 mV and 150 K). Even with un-optimized fabrication and standard commercial (mis-matched) read-out circuit technology, infrared images are obtained by the 320 × 256 IC focal plane array up to 180 K with f/2.3 optics. The minimum noise equivalent temperature difference of 28 mK is obtained at 120 K. These initial results indicate great potential of IC photodetectors, particularly for high operating temperature applications.

Tian, Z.-B.; Godoy, S. E.; Kim, H. S.; Schuler-Sandy, T.; Montoya, J. A.; Krishna, S.

2014-08-01

430

Solar Impulse's Solar-Powered Plane  

ScienceCinema

Solar Impulse lands in Washington, DC at Washington Dulles International Airport as part of its journey across the United States. Secretary Ernest Moniz speaks about how advancements like those at the Department of Energy are leading the way for innovations like the solar-powered plane. Footage of the solar-powered plane courtesy of Solar Impulse.

Moniz, Ernest; Piccard, Bertrand; Reicher, Dan

2014-01-07

431

BRIEF NOTES Thermoelastic Green's Functions for Plane  

E-print Network

of the coor- dinate axes, the governing equations of the plane problem could be reduced to Laplacian form of coordinates, equation (3) can be reduced to plane harmonic form. We define the modified complex variable z) With this notation, it follows that any distribution of the form T(xi,x2)=f(z,) satisfies equation (3) where f

Barber, James R.

432

Diffraction at a plane angular sector  

Microsoft Academic Search

A closed form solution is presented for the scattering in the far zone by a vertex at the interconnection between the two edges of a plane angular sector, when it is illuminated by a plane wave. The solution is obtained as a superposition of simple interaction mechanisms between the two adjacent edges. The spectral representation of the field diffracted by

S. Maci; R. Tiberio; A. Toccafondi

1994-01-01

433

Holographic nondestructive testing at the Fourier plane  

Microsoft Academic Search

A technique for the holographic nondestructive testing at the Fourier plane is proposed. An object's lateral and longitudinal rigid body translations are equivalent to linear and quadratic phase shifts in the object's Fourier spectrum. Thus a double-exposure hologram at the Fourier plane produces fringes on reconstruction which are straight for lateral and circular for longitudinal object translation. The fringes are

C. Roychoudhuri; R. Machorro

1978-01-01

434

Slipping and Rolling on an Inclined Plane  

ERIC Educational Resources Information Center

In the first part of the paper, using a direct calculation two-dimensional motion of a particle sliding on an inclined plane is investigated for general values of friction coefficient ([mu]). A parametric equation for the trajectory of the particle is also obtained. In the second part of the paper, the motion of a sphere on the inclined plane is…

Aghamohammadi, Cina; Aghamohammadi, Amir

2011-01-01

435

Blue E/S0 galaxies: merger remnants or disk rebuilding galaxies?  

E-print Network

Morphological early-type galaxies residing in the blue cloud (\\emph{blue E/S0s}) could be nice laboratories to understand the physical processes that provoke galaxy migrations in the color-mas space. We define blue E/S0 galaxies as objects having a clear early-type morphology on the HST/ACS images but with a blue rest-frame color. We isolate this way 210 $I_{AB}10^{10}$ in the COSMOS field located in three redshift bins ($0.2blue E/S0 resemble to merger remnants probably migrating to the red-sequence in a time-scale of $\\sim 3$ Gyr. Below this mass, they seem to be closer to normal late-type galaxies as if they were the result of minor mergers which triggered the central star-formation or were rebuilding a disk from the surrounding gas in a much longer time-scale, suggesting that they are moving back or staying in the blue-cloud.

López-Aguerri, J A; Tresse, L

2009-01-01

436

Quality analysis of blue-veined cheeses by MRI: a preliminary study  

Microsoft Academic Search

This paper describes a preliminary study aimed at improving the quality of soft-blue veined cheeses by the use of magnetic resonance images analysis. MRI measurements were performed on thirty-two samples from two different processing conditions and at three different stages from day 3 after the production to day 37. A segmentation algorithm based on a Self Organizing Map was used

Alexandru Onea; Guykaine Collewet; Christine Fernandez; Constantin Vertan; Noeul Richard; Francois Mariette

2003-01-01

437

Pontamine sky blue: A counterstain for background autofluorescence in fluorescence and immunofluorescence histochemistry  

Microsoft Academic Search

The stain pontamine sky blue (PSB) has been shown to reduce background autofluorescence in catecholamine fluorescence and immunofluorescence histochemical preparations. Using PSB as a counterstain on whole-mount stretch preparations of human mesenteric blood vessels, a medium dense noradrenergic nerve plexus is clearly revealed, which previously had been only partially visible because of background autofluorescence. Image analysis of nerve densities in

T. Cowen; A. J. Haven; G. Burnstock

1985-01-01

438

A feasibility study of a molecular-based patient setup verification method using a parallel-plane PET system  

NASA Astrophysics Data System (ADS)

A feasibility study of a novel PET-based molecular image guided radiation therapy (m-IGRT) system was conducted by comparing PET-based digitally reconstructed planar image (PDRI) registration with radiographic registration. We selected a pair of opposing parallel-plane PET systems for the practical implementation of this system. Planar images along the in-plane and cross-plane directions were reconstructed from the parallel-plane PET data. The in-plane and cross-plane FWHM of the profile of 2 mm diameter sources was approximately 1.8 and 8.1 mm, respectively. Therefore, only the reconstructed in-plane image from the parallel-plane PET data was used in the PDRI registration. In the image registration, five different sizes of 18F cylindrical sources (diameter: 8, 12, 16, 24, 32 mm) were used to determine setup errors. The data acquisition times were 1, 3 and 5 min. Image registration was performed by five observers to determine the setup errors from PDRI registration and radiographic registration. The majority of the mean registration errors obtained from the PDRI registration were not significantly different from those obtained from the radiographic registration. Acquisition time did not appear to result in significant differences in the mean registration error. The mean registration error for the PDRI registration was found to be 0.93 ± 0.33 mm. This is not statistically different from the radiographic registration which had a mean registration error of 0.92 ± 0.27 mm. Our results suggest that m-IGRT image registration using PET-based reconstructed planar images along the in-plane direction is feasible for clinical use if PDRI registration is performed at two orthogonal gantry angles.

Yamaguchi, Satoshi; Ishikawa, Masayori; Bengua, Gerard; Sutherland, Kenneth; Nishio, Teiji; Tanabe, Satoshi; Miyamoto, Naoki; Suzuki, Ryusuke; Shirato, Hiroki

2011-02-01

439

Study the Z-Plane Strip Capacitance  

SciTech Connect

The BaBaR detector at the Stanford Linear Accelerator Center is currently undergoing an upgrade to improve its muon and neutral hadron detection system. The Resistive Plate Chambers (RPCs) that had been used till now have deteriorated in performance over the past few years and are being replaced by Limited Streamer Tube (LSTs). Each layer of the system consists of a set of up to 10 streamer tube modules which provide one coordinate ({phi} coordinate) and a single ''Z-plane'' which provides the Z coordinate of the hit. The large area Z-planes (up to 12m{sup 2}) are 1mm thick and contain 96 copper strips that detect the induced charge from avalanches created in the streamer tube wires. All the Z-planes needed for the upgrade have already been constructed, but only a third of the planes were installed last summer. After installing the 24 Z-planes last year, it was learned that 0.7% of the strips were dead when put inside the detector. This was mainly due to the delicate solder joint between the read-out cable and the strip, and since it is difficult to access or replace the Z-planes inside the detector, it is very important to perform various tests to make sure that the Z-planes will be efficient and effective in the long term. We measure the capacitance between the copper strips and the ground plane, and compare it to the theoretical value that we expect. Instead of measuring the capacitance channel by channel, which would be a very tedious job, we developed a more effective method of measuring the capacitance. Since all the Z-planes were built at SLAC, we also built a smaller 46 cm by 30 cm Z-plane with 12 strips just to see how they were constructed and to gain a better understanding about the solder joints.

Parikh, H.; /Illinois U., Urbana; Swain, S.; /SLAC

2005-12-15

440

Phototherapy with turquoise versus blue light  

Microsoft Academic Search

Preterm jaundiced infants were treated by phototherapy with a new turquoise fluorescent lamp. This was more effective in reducing plasma total bilirubin in relation to light irradiance than the ubiquitously used blue fluorescent lamp.

F Ebbesen; G Agati; R Pratesi

2003-01-01

441

Blue Origin Conducts Pad Escape Test  

NASA Video Gallery

Blue Origin conducted a successful pad escape test Oct. 19 at the company's West Texas launch site, firing its pusher escape motor and launching a full-scale suborbital crew capsule from a simulate...

442

Subungual and periungual congenital blue naevus.  

PubMed

Subungual pigmented lesions should raise concern about malignant melanoma. Blue naevus of the nail apparatus is a rare entity, with only ten cases described in the literature. We report a 21-year-old Hispanic woman with a slowly enlarging 1.7 x 2.3-cm subungual and periungual pigmented plaque present since birth on her right second toe. Initial biopsy was consistent with a blue naevus of the cellular type and, given the recent clinical change and periungual extension, complete excision was recommended. The entire nail unit was resected down to periosteum with prior avulsion of the nail plate. Reconstruction was performed with a full-thickness skin graft. Follow up at 1 year revealed well-healed graft and donor sites with complete return of function. We present a case of a congenital subungual and periungual blue naevus of the cellular type and review the literature on this rare presentation of a congenital blue naevus. PMID:19397572

Gershtenson, Platina Coy; Krunic, Aleksandar; Chen, Helen; Konanahalli, Madhuri; Worobec, Sophie

2009-05-01

443

Blue Ribbon Commission Tour of Hanford Site  

SciTech Connect

The Blue Ribbon Commission on America's Nuclear Future toured the Department of Energy's Hanford Site on July 14, 2010. Commission members, invited guests, and members of the public visited facilities that store high-level, radioactive waste.

Paul Saueressig

2010-07-14

444

Blue Origin Tests BE-3 Engine  

NASA Video Gallery

Blue Origin successfully fires the thrust chamber assembly for its new 100,000 pound thrust BE-3 liquid oxygen, liquid hydrogen rocket engine. As part of the company's Reusable Booster System (RBS)...

445

Heparin sensing: Blue-chip binding  

E-print Network

Heparin is an anionic polysaccharide that has tremendous clinical importance as an anticoagulant. Several dyes have been developed that can detect heparin, and the latest example — named Mallard Blue — has now been shown ...

Shriver, Zachary H.

446

The Compact Disk of Blue Stars Orbiting the M31 Black Hole  

NASA Astrophysics Data System (ADS)

We propose ACS/HRC U and B band imaging of the compact cluster of blue stars at the precise center of M31, which hosts the 1.3X10^8 solar-mass nuclear black hole. Analysis of STIS spectra and WFPC2 images suggest that the cluster is actually a disk. Recovering an accurate light distribution of the disk is essential for obtaining a precise estimate of the black hole mass from the STIS spectra, an approach that is attractive as it bypasses modeling the complex structure and dynamics of the M31 double nucleus by using the Keplerian rotation of the blue disk as a direct mass indicator. Dithered ACS/HRC observations in the blue provide the best spatial resolution available from HST, which is 2X finer than could be obtained by the WFPC2 observations that first elucidated the structure of the blue cluster. The cluster effective radius {barely resolved by WFPC2} is only 0.06'', thus the ultimate resolution and improved S/N offered by re-observation with ACS/HRC are essential to fully understand the disk inclination and radial starlight distribution. Analysis of the "smoothness" of the blue light distribution may also reveal its composition. The low-luminosity of the disk, M{AB}=-5.5 can be produced by only a few hundred A-stars, a small enough number that fluctuation statistics should leave an obvious signature on the light distribution.

Lauer, Tod

2005-07-01

447

Dual-band technology on indium gallium arsenide focal plane arrays  

NASA Astrophysics Data System (ADS)

While InGaAs-based SWIR imaging technology has been improved dramatically over the past 10 years, the motivation remains to reduce Size Weight and Power (SWaP) for applications in Intelligence Surveillance and Reconnaissance (ISR). Goodrich ISR Systems, Princeton (Sensors Unlimited, Inc.) has continued to improve detector sensitivity. Additionally, SUI is working jointly with DRS-RSTA to develop innovative techniques for manufacturing dual-band focal planes to provide next generation technology for not only reducing SWaP for SWIR imagers, but also to combine imaging solutions for providing a single imager for Visible Near-SWIR (VNS) + LW imaging solutions. Such developments are targeted at reducing system SWaP, cost and complexity for imaging payloads on board UASs as well as soldier deployed systems like weapon sights. Our motivation is to demonstrate capability in providing superior image quality in fused LWIR and SWIR imaging systems, while reducing the total system SWaP and cost by enabling Short Wave and Thermal imaging in a single uncooled imager. Under DARPA MTO awarded programs, a LW bolometer (DRS-RSTA) is fabricated on a Short Wave (SW) InGaAs Vis-SWIR (SUI-Goodrich) Imager. The combined imag