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Sample records for acoustic holography nah

  1. Nearfield acoustic holography. I - Theory of generalized holography and the development of NAH

    NASA Technical Reports Server (NTRS)

    Maynard, J. D.; Williams, E. G.; Lee, Y.

    1985-01-01

    Because its underlying principles are so fundamental, holography has been studied and applied in many areas of science. Recently, a technique has been developed which takes the maximum advantage of the fundamental principles and extracts much more information from a hologram than is customarily associated with such a measurement. In this paper the fundamental principles of holography are reviewed, and a sound radiation measurement system, called nearfield acoustic holography (NAH), which fully exploits the fundamental principles, is described.

  2. Nearfield Acoustical Holography

    NASA Astrophysics Data System (ADS)

    Hayek, Sabih I.

    Nearfield acoustical holography (NAH) is a method by which a set of acoustic pressure measurements at points located on a specific surface (called a hologram) can be used to image sources on vibrating surfaces on the acoustic field in three-dimensional space. NAH data are processed to take advantage of the evanescent wavefield to image sources that are separated less that one-eighth of a wavelength.

  3. Regularization methods for near-field acoustical holography.

    PubMed

    Williams, E G

    2001-10-01

    The reconstruction of the pressure and normal surface velocity provided by near-field acoustical holography (NAH) from pressure measurements made near a vibrating structure is a linear, ill-posed inverse problem due to the existence of strongly decaying, evanescentlike waves. Regularization provides a technique of overcoming the ill-posedness and generates a solution to the linear problem in an automated way. We present four robust methods for regularization; the standard Tikhonov procedure along with a novel improved version, Landweber iteration, and the conjugate gradient approach. Each of these approaches can be applied to all forms of interior or exterior NAH problems; planar, cylindrical, spherical, and conformal. We also study two parameter selection procedures, the Morozov discrepancy principle and the generalized cross validation, which are crucial to any regularization theory. In particular, we concentrate here on planar and cylindrical holography. These forms of NAH which rely on the discrete Fourier transform are important due to their popularity and to their tremendous computational speed. In order to use regularization theory for the separable geometry problems we reformulate the equations of planar, cylindrical, and spherical NAH into an eigenvalue problem. The resulting eigenvalues and eigenvectors couple easily to regularization theory, which can be incorporated into the NAH software with little sacrifice in computational speed. The resulting complete automation of the NAH algorithm for both separable and nonseparable geometries overcomes the last significant hurdle for NAH.

  4. A refined wideband acoustical holography based on equivalent source method

    PubMed Central

    Ping, Guoli; Chu, Zhigang; Xu, Zhongming; Shen, Linbang

    2017-01-01

    This paper is concerned with acoustical engineering and mathematical physics problem for the near-field acoustical holography based on equivalent source method (ESM-based NAH). An important mathematical physics problem in ESM-based NAH is to solve the equivalent source strength, which has multiple solving algorithms, such as Tikhonov regularization ESM (TRESM), iterative weighted ESM (IWESM) and steepest descent iteration ESM (SDIESM). To explore a new solving algorithm which can achieve better reconstruction performance in wide frequency band, a refined wideband acoustical holography (RWAH) is proposed. RWAH adopts IWESM below a transition frequency and switches to SDIESM above that transition frequency, and the principal components of input data in RWAH have been truncated. Further, the superiority of RWAH is verified by the comparison of comprehensive performance of TRESM, IWESM, SDIESM and RWAH. Finally, the experiments are conducted, confirming that RWAH can achieve better reconstruction performance in wide frequency band. PMID:28266531

  5. A refined wideband acoustical holography based on equivalent source method

    NASA Astrophysics Data System (ADS)

    Ping, Guoli; Chu, Zhigang; Xu, Zhongming; Shen, Linbang

    2017-03-01

    This paper is concerned with acoustical engineering and mathematical physics problem for the near-field acoustical holography based on equivalent source method (ESM-based NAH). An important mathematical physics problem in ESM-based NAH is to solve the equivalent source strength, which has multiple solving algorithms, such as Tikhonov regularization ESM (TRESM), iterative weighted ESM (IWESM) and steepest descent iteration ESM (SDIESM). To explore a new solving algorithm which can achieve better reconstruction performance in wide frequency band, a refined wideband acoustical holography (RWAH) is proposed. RWAH adopts IWESM below a transition frequency and switches to SDIESM above that transition frequency, and the principal components of input data in RWAH have been truncated. Further, the superiority of RWAH is verified by the comparison of comprehensive performance of TRESM, IWESM, SDIESM and RWAH. Finally, the experiments are conducted, confirming that RWAH can achieve better reconstruction performance in wide frequency band.

  6. Underwater hybrid near-field acoustical holography based on the measurement of vector hydrophone array

    NASA Astrophysics Data System (ADS)

    Hu, Bo; Yang, Desen; Sun, Yu

    2010-06-01

    Hybrid near-field acoustical holography (NAH) is developed for reconstructing acoustic radiation from a cylindrical source in a complex underwater environment. In hybrid NAH, we combine statistically optimized near-field acoustical holography (SONAH) and broadband acoustical holography from intensity measurements (BAHIM) to reconstruct the underwater cylindrical source field. First, the BAHIM is utilized to regenerate as much acoustic pressures on the hologram surface as necessary, and then the acoustic pressures are taken as input to the formulation implemented numerically by SONAH. The main advantages of this technology are that the complex pressure on the hologram surface can be reconstructed without reference signal, and the measurement array can be smaller than the source, thus the practicability and efficiency of this technology are greatly enhanced. Numerical examples of a cylindrical source are demonstrated. Test results show that hybrid NAH can yield a more accurate reconstruction than conventional NAH. Then, an experiment has been carried out with a vector hydrophone array. The experimental results show the advantage of hybrid NAH in the reconstruction of an acoustic field and the feasibility of using a vector hydrophone array in an underwater NAH measurement, as well as the identification and localization of noise sources.

  7. Acoustic emission linear pulse holography

    SciTech Connect

    Collins, H.D.; Busse, L.J.; Lemon, D.K.

    1983-10-25

    This device relates to the concept of and means for performing Acoustic Emission Linear Pulse Holography, which combines the advantages of linear holographic imaging and Acoustic Emission into a single non-destructive inspection system. This unique system produces a chronological, linear holographic image of a flaw by utilizing the acoustic energy emitted during crack growth. The innovation is the concept of utilizing the crack-generated acoustic emission energy to generate a chronological series of images of a growing crack by applying linear, pulse holographic processing to the acoustic emission data. The process is implemented by placing on a structure an array of piezoelectric sensors (typically 16 or 32 of them) near the defect location. A reference sensor is placed between the defect and the array.

  8. Leakage detection and quantification techniques using various methods of nearfield acoustic holography

    NASA Astrophysics Data System (ADS)

    Chelliah, Kanthasamy

    This thesis proposes an acoustic technique to detect and relatively quantify leakages in buildings and enclosures using various methods of nearfield acoustic holography (NAH). This laboratory study was performed on a scaled, wooden building model. Known leakages can be created in the wooden model and the acoustic method was tested to localize and relatively quantify these known leakage areas. An acoustic source was placed inside the building model and a planar hologram measurement was performed near the surface of the building model. Various methods of NAH were applied on the hologram data to reconstruct the sound pressure field on the wall of the building model. The detection and quantification capabilities of four different NAH methods, namely, discrete Fourier transform (DFT) based NAH, equivalent source model (ESM) based NAH, boundary element method (BEM) based NAH and statistically optimized NAH (SONAH), were compared in this study. It was shown that the NAH methods were able to successfully locate and relatively quantify the area of the leakages using the reconstructions. Although all the four algorithms produced comparable results in the very nearfield, at larger hologram distances, ESM and SONAH reconstructions were more accurate than the reconstructions using the other methods. Although, ESM and SONAH produced similar results for most of the cases, ESM is more preferable due to its simplicity in implementation and less computational time requirements. Lower frequency reconstructions were found to be more accurate and advantageous in the context of leakage detection and quantification. When the hologram distance was increased more than a particular limit, all the four algorithms arrive at inaccurate reconstructions due to the very ill-conditioned propagation matrices. New filtering methods to alleviate these larger reconstruction errors were introduced and the results were demonstrated. Effects of large sensor phase mismatch were also studied. It was

  9. Research on Diagnosing the Gearbox Faults Based on Near Field Acoustic Holography

    NASA Astrophysics Data System (ADS)

    Jiang, W. K.; Hou, J. J.; Xing, J. T.

    2011-07-01

    The gearbox fault diagnosis was developed for some decades. The current diagnosis techniques were mostly based on analyzing the shell vibration signals especially close to the bearing seat of gearbox. In order to utilize the spatial distribution information of fault signal, the near field acoustic holography (NAH) is employed for the condition monitoring and fault diagnosis of the gearbox in this presentation. The distribution images of sound pressure on the surface of gearbox are reconstructed by NAH, and the feature extraction and pattern recognition can be made by image processing techniques. A gearbox is studied in a semi-anechoic chamber to verify the fault diagnosis technique based on NAH. The pitting and partial broken tooth faults of gears are artificially made on one gear as the fault statuses, and the differences of acoustic images among normal and fault working states under the idling condition are analyzed. It can be found that the acoustic images of gearbox in the three different situations change regularly, and the main sound sources can be recognized from the acoustic images which also contain rich diagnosis information. After feature extraction of the acoustic images, the pattern reorganization technique is employed for diagnosis. The results indicate that this diagnosis procedure based on acoustic images is available and feasible for the gearbox fault diagnosis.

  10. Acoustic-emission linear-pulse holography

    SciTech Connect

    Collins, H.D.; Lemon, D.K.; Busse, L.J.

    1982-06-01

    This paper describes Acoustic Emission Linear Pulse Holography which combines the advantages of linear imaging and acoustic emission into a single NDE inspection system. This unique system produces a chronological linear holographic image of a flaw by utilizing the acoustic energy emitted during crack growth. Conventional linear holographic imaging uses an ultrasonic transducer to transmit energy into the volume being imaged. When the crack or defect reflects that energy, the crack acts as a new source of acoustic waves. To formulate an image of that source, a receiving transducer is scanned over the volume of interest and the phase of the received signals is measured at successive points on the scan. The innovation proposed here is the utilization of the crack generated acoustic emission as the acoustic source and generation of a line image of the crack as it grows. A thirty-two point sampling array is used to construct phase-only linear holograms of simulated acoustic emission sources on large metal plates. The phases are calculated using the pulse time-of-flight (TOF) times from the reference transducer to the array of receivers. Computer reconstruction of the image is accomplished using a one-dimensional FFT algorithm (i.e., backward wave). Experimental results are shown which graphically illustrate the unique acoustic emission images of a single point and a linear crack in a 100 mm x 1220 mm x 1220 mm aluminum plate.

  11. Acoustic emission linear pulse holography

    DOEpatents

    Collins, H. Dale; Busse, Lawrence J.; Lemon, Douglas K.

    1985-01-01

    Defects in a structure are imaged as they propagate, using their emitted acoustic energy as a monitored source. Short bursts of acoustic energy propagate through the structure to a discrete element receiver array. A reference timing transducer located between the array and the inspection zone initiates a series of time-of-flight measurements. A resulting series of time-of-flight measurements are then treated as aperture data and are transferred to a computer for reconstruction of a synthetic linear holographic image. The images can be displayed and stored as a record of defect growth.

  12. Acoustic emission linear pulse holography

    SciTech Connect

    Collins, H. D.; Busse, L. J.; Lemon, D. K.

    1985-07-30

    Defects in a structure are imaged as they propagate, using their emitted acoustic energy as a monitored source. Short bursts of acoustic energy propagate through the structure to a discrete element receiver array. A reference timing transducer located between the array and the inspection zone initiates a series of time-of-flight measurements. A resulting series of time-of-flight measurements are then treated as aperture data and are transferred to a computer for reconstruction of a synthetic linear holographic image. The images can be displayed and stored as a record of defect growth.

  13. Experimental study using Nearfield Acoustical Holography of sound transmission fuselage sidewall structures

    NASA Technical Reports Server (NTRS)

    Maynard, J. D.

    1983-01-01

    This project involves the development of the Nearfield Acoustic Holography (NAH) technique (in particular its extension from single frequency to wideband noise measurement) and its application in a detailed study of the noise radiation characteristics of several samples of aircraft sidewall panels. With the extensive amount of information provided by the NAH technique, the properties of the sound field radiated by the panels may be correlated with their structure, mounting, and excitation (single frequency or wideband, spatially correlated or uncorrelated, structure-borne). The work accomplished at the beginning of this grant period included: (1) Calibration of the 256 microphone array and test of its accuracy. (2) extension of the facility to permit measurements on wideband noise sources. The extensions incuded the addition of high-speed data acquisition hardware and an array processor, and the development of new software. (3) Installation of motion picture graphics for correlating panel motion with structure, mounting, radiation, etc. (4) Development of new holographic data processing techniques.

  14. Near field acoustic holography measurements of carbon nanotube thin film speakers.

    PubMed

    Asgarisabet, Mahsa; Barnard, Andrew R; Bouman, Troy M

    2016-12-01

    Carbon nanotube (CNT) thin film speakers produce sound with the thermoacoustic effect. Better understanding of the physical acoustic properties of these speakers will drive future design improvements. Measuring acoustic properties at the surface of the CNT thin film is difficult because the films, themselves, do not vibrate, are fragile and have a high surface temperature. In order to measure the surface particle velocity and sound pressure level (SPL), near field acoustic holography (NAH) has been used by employing probe microphones. NAH images the acoustic quantities of the source system using the set of acoustic pressure measurements on a hologram parallel to the source surface. It is shown that the particle velocity at the surface of an open-air, double-sided speaker is nominally zero, as expected. However, the SPL distribution is not uniform on the source surface, contrary to common lumped parameter model assumptions. Also, particle velocity and sound intensity distributions on the hologram have been obtained in this study. Finally, measured directivity patterns of the planar CNT speaker are reported.

  15. Identification of vibration excitations from acoustic measurements using near field acoustic holography and the force analysis technique

    NASA Astrophysics Data System (ADS)

    Pézerat, C.; Leclère, Q.; Totaro, N.; Pachebat, M.

    2009-10-01

    This study presents a method of using acoustic holography and the force analysis technique to identify vibration sources from radiated noise measurements. The structure studied is a plate excited by a shaker on which three measurements were performed: the first is a reference measurement of plate velocity obtained by scanning laser vibrometry, the second is based on sound pressure measurements in the near field of the structure, and the third is the measurement of normal acoustic velocities by using a p-U probe recently developed by Microflown Technologies. This was followed by the application of classical NAH, known as pressure-to-velocity holography and velocity-to-velocity holography to predict the plate velocity field from acoustic measurements at distances of 1 and 5 cm. Afterwards, the force analysis technique, also known as the RIFF technique, is applied with these five data sets. The principle is to inject the displacement field of the structure into its equation of motion and extract the resulting force distribution. This technique requires regularization done by a low-pass filter in the wavenumber domain. Apart from pressure-to-velocity holography at 5 cm, the reconstructed force distribution allows localizing the excitation point in the measurement area. FAT regularization is also shown to improve results as its cutoff wavenumber is optimized with the natural wavenumber of the plate. Lastly, quantitative force values are extracted from force distributions at all frequencies of the band 0-4 kHz studied and compared with the force spectrum measured directly by a piezoelectric sensor.

  16. Near-field acoustic holography using sparse regularization and compressive sampling principles.

    PubMed

    Chardon, Gilles; Daudet, Laurent; Peillot, Antoine; Ollivier, François; Bertin, Nancy; Gribonval, Rémi

    2012-09-01

    Regularization of the inverse problem is a complex issue when using near-field acoustic holography (NAH) techniques to identify the vibrating sources. This paper shows that, for convex homogeneous plates with arbitrary boundary conditions, alternative regularization schemes can be developed based on the sparsity of the normal velocity of the plate in a well-designed basis, i.e., the possibility to approximate it as a weighted sum of few elementary basis functions. In particular, these techniques can handle discontinuities of the velocity field at the boundaries, which can be problematic with standard techniques. This comes at the cost of a higher computational complexity to solve the associated optimization problem, though it remains easily tractable with out-of-the-box software. Furthermore, this sparsity framework allows us to take advantage of the concept of compressive sampling; under some conditions on the sampling process (here, the design of a random array, which can be numerically and experimentally validated), it is possible to reconstruct the sparse signals with significantly less measurements (i.e., microphones) than classically required. After introducing the different concepts, this paper presents numerical and experimental results of NAH with two plate geometries, and compares the advantages and limitations of these sparsity-based techniques over standard Tikhonov regularization.

  17. Acoustic holography. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Reed, W. E.

    1980-07-01

    Aspects of acoustic holography are covered in this bibliography of Federally funded research. Theory, equipment design, uses, and imaging techniques are presented. The applications include underwater and underground object locating, structural geology and tectonics, sonar imaging, non destructive testing, antenna radiation patterns, nuclear reactor inspection, remote sensing, and use in medical examination. This updated bibliography contains 166 citations, 15 of which are new entries to the previous edition.

  18. Experimental study of the mapping relationship based near-field acoustic holography with spherical fundamental solutions

    NASA Astrophysics Data System (ADS)

    Wu, Haijun; Jiang, Weikang

    2017-04-01

    This paper is a consequent work of the previously proposed mapping relationship based near-field acoustic holography (MRS-based NAH), [H.J.Wu W.K. Jiang and H.B. Zhang, JSV, 373:66-88, 2016]. It is devoted to the performance study of its practical application with error analysis and experimental validation. Two types of errors, the truncation errors due to the limited number of participant modes, and the inevitable measurement errors caused by uncertainties in the experiment, are considered in the analysis. The influences of the errors on the performance of MRS-based NAH are systematically investigated. First of all, expression of the relative reconstruction error of the pressure energy is derived based on the two types of errors. An approach is developed to estimate the lower and upper bounds of the relative error. It gives a guide to predict the error for a reconstruction under the condition that the truncation error and the signal-to-noise ratio are given. Then, the condition number of the inverse operator is investigated to measure the sensitivity of the reconstruction to the input errors. Asymptotic expressions of the condition number for a special case, conformal spherical model and hologram, are obtained, which indicates the condition number has a geometric growth with the number of participant modes. Numerical examples with different kinds of errors are elaborately designed to validate the stability as well as the correctness of the error analysis. At last, the MRS-based NAH is further examined and verified by a physical experiment, a vibrating cubic model reconstructed from measurement on a spherical hologram. A satisfied agreement with the directly measured pressure on a validation surface is observed for both quantity and distribution of the reconstructed pressure.

  19. Complete de-Dopplerization and acoustic holography for external noise of a high-speed train.

    PubMed

    Yang, Diange; Wen, Junjie; Miao, Feng; Wang, Ziteng; Gu, Xiaoan; Lian, Xiaomin

    2016-09-01

    Identification and measurement of moving sound sources are the bases for vehicle noise control. Acoustic holography has been applied in successfully identifying the moving sound source since the 1990s. However, due to the high demand for the accuracy of holographic data, currently the maximum velocity achieved by acoustic holography is just above 100 km/h. The objective of this study was to establish a method based on the complete Morse acoustic model to restore the measured signal in high-speed situations, and to propose a far-field acoustic holography method applicable for high-speed moving sound sources. Simulated comparisons of the proposed far-field acoustic holography with complete Morse model, the acoustic holography with simplified Morse model and traditional delay-and-sum beamforming were conducted. Experiments with a high-speed train running at the speed of 278 km/h validated the proposed far-field acoustic holography. This study extended the applications of acoustic holography to high-speed situations and established the basis for quantitative measurements of far-field acoustic holography.

  20. On optimal retreat distance for the equivalent source method-based nearfield acoustical holography.

    PubMed

    Bai, Mingsian R; Chen, Ching-Cheng; Lin, Jia-Hong

    2011-03-01

    As a basic form of the equivalent source method (ESM) that is used to nearfield acoustical holography (NAH) problems, discrete monopoles are utilized to represent the sound field of interest. When setting up the virtual source distribution, it is vital to maintain a "retreat distance" between the virtual sources and the actual source surface such that reconstruction would not suffer from singularity problems. However, one cannot increase the distance without bound because of the ill-posedness inherent in the reconstruction process with large distance. In prior research, 1-2 times lattice spacing, or the inter-element distance of microphones, is generally recommended as retreat distance in using the ESM-based NAH. While this rule has shown to yield good results in many cases, the optimal choice is a complicated issue that depends on frequency, geometry of the physical source, content of evanescent waves, distribution of sensors and virtual sources, etc. This paper deals about attaining the best compromise between the reconstruction errors induced by the point source singularity; the reconstruction ill-posedness is an interesting problem in its own right. The paper revisits this issue, with the aid of an optimization algorithm based on the golden section search and parabolic interpolation. Numerical simulations were conducted for a baffled planar piston source and a spherically baffled piston source. The results revealed that the retreat distance appropriate for the ESM ranged from 0.4 to 0.5 times the spacing for the planar piston, while from 0.8 to 1.7 times average spacing for the spherical piston. Experiments carried out for a vibrating aluminum plate also revealed that the retreat distance with 0.5 times the spacing yielded better reconstructed velocity than those with 1/20 and 1 times the spacing.

  1. Cylindrical acoustical holography applied to full-scale jet noise.

    PubMed

    Wall, Alan T; Gee, Kent L; Neilsen, Tracianne B; Krueger, David W; James, Michael M

    2014-09-01

    Near-field acoustical holography methods are used to predict sound radiation from an engine installed on a high-performance military fighter aircraft. Cylindrical holography techniques are an efficient approach to measure the large and complex sound fields produced by full-scale jets. It is shown that a ground-based, one-dimensional array of microphones can be used in conjunction with a cylindrical wave function field representation to provide a holographic reconstruction of the radiated sound field at low frequencies. In the current work, partial field decomposition methods and numerical extrapolation of data beyond the boundaries of the hologram aperture are required prior to holographic projection. Predicted jet noise source distributions and directionality are shown for four frequencies between 63 and 250 Hz. It is shown that the source distribution narrows and moves upstream, and that radiation directionality shifts toward the forward direction, with increasing frequency. A double-lobe feature of full-scale jet radiation is also demonstrated.

  2. Near-field acoustical holography of military jet aircraft noise

    NASA Astrophysics Data System (ADS)

    Wall, Alan T.; Gee, Kent L.; Neilsen, Tracianne; Krueger, David W.; Sommerfeldt, Scott D.; James, Michael M.

    2010-10-01

    Noise radiated from high-performance military jet aircraft poses a hearing-loss risk to personnel. Accurate characterization of jet noise can assist in noise prediction and noise reduction techniques. In this work, sound pressure measurements were made in the near field of an F-22 Raptor. With more than 6000 measurement points, this is the most extensive near-field measurement of a high-performance jet to date. A technique called near-field acoustical holography has been used to propagate the complex pressure from a two- dimensional plane to a three-dimensional region in the jet vicinity. Results will be shown and what they reveal about jet noise characteristics will be discussed.

  3. A gearbox fault diagnosis scheme based on near-field acoustic holography and spatial distribution features of sound field

    NASA Astrophysics Data System (ADS)

    Lu, Wenbo; Jiang, Weikang; Yuan, Guoqing; Yan, Li

    2013-05-01

    Vibration signal analysis is the main technique in machine condition monitoring or fault diagnosis, whereas in some cases vibration-based diagnosis is restrained because of its contact measurement. Acoustic-based diagnosis (ABD) with non-contact measurement has received little attention, although sound field may contain abundant information related to fault pattern. A new scheme of ABD for gearbox based on near-field acoustic holography (NAH) and spatial distribution features of sound field is presented in this paper. It focuses on applying distribution information of sound field to gearbox fault diagnosis. A two-stage industrial helical gearbox is experimentally studied in a semi-anechoic chamber and a lab workshop, respectively. Firstly, multi-class faults (mild pitting, moderate pitting, severe pitting and tooth breakage) are simulated, respectively. Secondly, sound fields and corresponding acoustic images in different gearbox running conditions are obtained by fast Fourier transform (FFT) based NAH. Thirdly, by introducing texture analysis to fault diagnosis, spatial distribution features are extracted from acoustic images for capturing fault patterns underlying the sound field. Finally, the features are fed into multi-class support vector machine for fault pattern identification. The feasibility and effectiveness of our proposed scheme is demonstrated on the good experimental results and the comparison with traditional ABD method. Even with strong noise interference, spatial distribution features of sound field can reliably reveal the fault patterns of gearbox, and thus the satisfactory accuracy can be obtained. The combination of histogram features and gray level gradient co-occurrence matrix features is suggested for good diagnosis accuracy and low time cost.

  4. Holography.

    ERIC Educational Resources Information Center

    Klein, H. Arthur

    Holography is a process which numbers among its many applications the creation of holograms--unique three dimensional photographs that show spatial relations and shifts just as they exist in reality. This book recounts the history of holography, tracing its development from Euclid's theory of light rays through Huygens' theory of wave motion to…

  5. Analytical study of acousto/optical holography-interfacing methods for acoustical and optical holography NDT research

    NASA Technical Reports Server (NTRS)

    El-Sum, H. M. A.

    1976-01-01

    The international status of the art of acousto optical imaging techniques adaptable to nondestructive testing and, interfacing methods for acoustical and optical holography in nondestructive testing research are studied. Evaluation of 20 different techniques encompassed investigation of varieties of detectors and detection schemes, all of which are described and summarized. Related investigation is reported in an Appendix. Important remarks on image quality, factors to be considered in designing a particular system, and conclusions and recommendations are presented. Three bibliographies are included.

  6. Haptic Holography: Acoustic Space and the Evolution of the Whole Message

    NASA Astrophysics Data System (ADS)

    Logan, N.

    2013-02-01

    The paper argues that the Haptic Holography Work Station is an example of a medium that fit's with McLuhan's notion of Acoustic Space, that is it is a medium which stimulates more than one sense of perception at a time. As a result, the Haptic Holography Work Station transmits information about the subject much more rapidly than other media that precedes it, be it text, photography or television.

  7. Enhanced nearfield acoustic holography for larger distances of reconstructions using fixed parameter Tikhonov regularization

    DOE PAGES

    Chelliah, Kanthasamy; Raman, Ganesh G.; Muehleisen, Ralph T.

    2016-07-07

    This paper evaluates the performance of various regularization parameter choice methods applied to different approaches of nearfield acoustic holography when a very nearfield measurement is not possible. For a fixed grid resolution, the larger the hologram distance, the larger the error in the naive nearfield acoustic holography reconstructions. These errors can be smoothed out by using an appropriate order of regularization. In conclusion, this study shows that by using a fixed/manual choice of regularization parameter, instead of automated parameter choice methods, reasonably accurate reconstructions can be obtained even when the hologram distance is 16 times larger than the grid resolution.

  8. Tomographic reconstruction of transient acoustic fields recorded by pulsed TV holography.

    PubMed

    Gren, P; Schedin, S; Li, X

    1998-02-10

    Pulsed TV holography combined with computerized tomography (CT) are used to evaluate the three-dimensional distribution of transient acoustic fields in air. Experiments are performed with an electrical discharge between two electrodes as the sound source. Holograms from several directions of the acoustic field are recorded directly onto a CCD detector by use of a double-pulsed ruby laser as the light source. Phase maps, representing projections of the acoustic field, are evaluated quantitatively from the recorded holograms. The projections are used for the CT reconstruction to evaluate the pressure-field distribution in any cross section of the measured volume of air.

  9. Military jet noise source imaging using multisource statistically optimized near-field acoustical holography.

    PubMed

    Wall, Alan T; Gee, Kent L; Neilsen, Tracianne B; McKinley, Richard L; James, Michael M

    2016-04-01

    The identification of acoustic sources is critical to targeted noise reduction efforts for jets on high-performance tactical aircraft. This paper describes the imaging of acoustic sources from a tactical jet using near-field acoustical holography techniques. The measurement consists of a series of scans over the hologram with a dense microphone array. Partial field decomposition methods are performed to generate coherent holograms. Numerical extrapolation of data beyond the measurement aperture mitigates artifacts near the aperture edges. A multisource equivalent wave model is used that includes the effects of the ground reflection on the measurement. Multisource statistically optimized near-field acoustical holography (M-SONAH) is used to reconstruct apparent source distributions between 20 and 1250 Hz at four engine powers. It is shown that M-SONAH produces accurate field reconstructions for both inward and outward propagation in the region spanned by the physical hologram measurement. Reconstructions across the set of engine powers and frequencies suggests that directivity depends mainly on estimated source location; sources farther downstream radiate at a higher angle relative to the inlet axis. At some frequencies and engine powers, reconstructed fields exhibit multiple radiation lobes originating from overlapped source regions, which is a phenomenon relatively recently reported for full-scale jets.

  10. Underwater patch near-field acoustical holography based on particle velocity and vector hydrophone array

    NASA Astrophysics Data System (ADS)

    Hu, Bo; Yang, DeSen; Li, SiChun; Sun, Yu; Mo, ShiQi; Shi, ShengGuo

    2012-11-01

    One-step patch near-field acoustical holography (PNAH) is a powerful tool for identifying noise sources from the partially known sound pressure field. The acoustical property to be reconstructed on the surface of interest is related to the partially measured pressure on the hologram surface in terms of sampling and bandlimiting matrices, which cost more in computation. A one-step procedure based on measuring of the normal component of the particle velocity is described, including the mathematical formulation. The numerical simulation shows that one-step PNAH based on particle velocity can obtain more accurately reconstructed results and it is also less sensitive to noise than the method based on pressure. These findings are confirmed by an underwater near-field acoustical holography experiment conducted with a vector hydrophone array. The experimental results have illustrated the high performance of one-step PNAH based on particle velocity in the reconstruction of sound field and the advantages of a vector hydrophone array in an underwater near-field measurement.

  11. Acoustic holography as a metrological tool for characterizing medical ultrasound sources and fields

    PubMed Central

    Sapozhnikov, Oleg A.; Tsysar, Sergey A.; Khokhlova, Vera A.; Kreider, Wayne

    2015-01-01

    Acoustic holography is a powerful technique for characterizing ultrasound sources and the fields they radiate, with the ability to quantify source vibrations and reduce the number of required measurements. These capabilities are increasingly appealing for meeting measurement standards in medical ultrasound; however, associated uncertainties have not been investigated systematically. Here errors associated with holographic representations of a linear, continuous-wave ultrasound field are studied. To facilitate the analysis, error metrics are defined explicitly, and a detailed description of a holography formulation based on the Rayleigh integral is provided. Errors are evaluated both for simulations of a typical therapeutic ultrasound source and for physical experiments with three different ultrasound sources. Simulated experiments explore sampling errors introduced by the use of a finite number of measurements, geometric uncertainties in the actual positions of acquired measurements, and uncertainties in the properties of the propagation medium. Results demonstrate the theoretical feasibility of keeping errors less than about 1%. Typical errors in physical experiments were somewhat larger, on the order of a few percent; comparison with simulations provides specific guidelines for improving the experimental implementation to reduce these errors. Overall, results suggest that holography can be implemented successfully as a metrological tool with small, quantifiable errors. PMID:26428789

  12. Acoustic holography as a metrological tool for characterizing medical ultrasound sources and fields.

    PubMed

    Sapozhnikov, Oleg A; Tsysar, Sergey A; Khokhlova, Vera A; Kreider, Wayne

    2015-09-01

    Acoustic holography is a powerful technique for characterizing ultrasound sources and the fields they radiate, with the ability to quantify source vibrations and reduce the number of required measurements. These capabilities are increasingly appealing for meeting measurement standards in medical ultrasound; however, associated uncertainties have not been investigated systematically. Here errors associated with holographic representations of a linear, continuous-wave ultrasound field are studied. To facilitate the analysis, error metrics are defined explicitly, and a detailed description of a holography formulation based on the Rayleigh integral is provided. Errors are evaluated both for simulations of a typical therapeutic ultrasound source and for physical experiments with three different ultrasound sources. Simulated experiments explore sampling errors introduced by the use of a finite number of measurements, geometric uncertainties in the actual positions of acquired measurements, and uncertainties in the properties of the propagation medium. Results demonstrate the theoretical feasibility of keeping errors less than about 1%. Typical errors in physical experiments were somewhat larger, on the order of a few percent; comparison with simulations provides specific guidelines for improving the experimental implementation to reduce these errors. Overall, results suggest that holography can be implemented successfully as a metrological tool with small, quantifiable errors.

  13. Acoustic Holography of the Solar Convection Zone with SOHO-MDI Observations

    NASA Technical Reports Server (NTRS)

    Lindsey, Charles

    2005-01-01

    The original grant with the title stated above was NAG5-10984, awarded to the Solar Physics Research Corporation (SPRC) in July, 2001, and was to be a three-year project. The basic theme of the project was the development and application of computational seismic holography for imaging, diagnostics, and monitoring of magnetic anomalies beneath active regions, in the deep solar interior, and on the Sun's far surface. The project was roughly separated into the following five tasks: (1) A holographic survey of active regions. (2) p-Mode absorption diagnostics of magnetic regions. (3) Acoustic modeling of the shallow subphotospheres of active regions and the quiet-Sun supergranulation based on phase-correlation seismic holography. (4) Seismic holography of the deep convection zone. (5) Improvements in holographic imaging of the far surface of the Sun. Following the death of Karen Harvey, President of SPRC, during the first year, the grant was transferred to Northwest Research Associates as NAG5-12901. Substantial but progress had been made on most of the above tasks in the first year under NAG5-10984, but none were completed. This work was continued under NAG5-12901.

  14. Investigation of 3D surface acoustic waves in granular media with 3-color digital holography

    NASA Astrophysics Data System (ADS)

    Leclercq, Mathieu; Picart, Pascal; Penelet, Guillaume; Tournat, Vincent

    2017-01-01

    This paper reports the implementation of digital color holography to investigate elastic waves propagating along a layer of a granular medium. The holographic set-up provides simultaneous recording and measurement of the 3D dynamic displacement at the surface. Full-field measurements of the acoustic amplitude and phase at different excitation frequencies are obtained. It is shown that the experimental data can be used to obtain the dispersion curve of the modes propagating in this granular medium layer. The experimental dispersion curve and that obtained from a finite element modeling of the problem are found to be in good agreement. In addition, full-field images of the interaction of an acoustic wave guided in the granular layer with a buried object are also shown.

  15. Developing a confocal acoustic holography microscope for non-invasive 3D temperature and composition measurements.

    PubMed

    Herring, Rodney A; Jacquemin, Peter; Sawicka, Barbara D; Atalick, Stefan

    2009-06-01

    A confocal acoustic holography microscope (CAHM) has been designed, simulated and partially verified experimentally to take holograms for non-invasive, three-dimensional measurements of a specimen's refractive indices from one view point. The designed and simulated prototype CAHM used a frequency of 2.25 MHz and measured sound speed changes of 16 m/s, temperature changes of 5 degrees C and had a spatial resolution of 660 microm. With future improvements utilizing the latest technologies such as two-dimensional array detectors, Micro-Electro-Mechanical Systems (MEMS), and acoustic lenses, resolutions of 1m/s, 0.5 degrees C, and 150 microm are expected. The CAHM is expected to have many useful applications, including non-invasive mass and heat transfer measurements in fluids and materials and as a medical diagnostic tool to non-intrusively visualize compositions and temperatures within the human body.

  16. A sparse equivalent source method for near-field acoustic holography.

    PubMed

    Fernandez-Grande, Efren; Xenaki, Angeliki; Gerstoft, Peter

    2017-01-01

    This study examines a near-field acoustic holography method consisting of a sparse formulation of the equivalent source method, based on the compressive sensing (CS) framework. The method, denoted Compressive-Equivalent Source Method (C-ESM), encourages spatially sparse solutions (based on the superposition of few waves) that are accurate when the acoustic sources are spatially localized. The importance of obtaining a non-redundant representation, i.e., a sensing matrix with low column coherence, and the inherent ill-conditioning of near-field reconstruction problems is addressed. Numerical and experimental results on a classical guitar and on a highly reactive dipole-like source are presented. C-ESM is valid beyond the conventional sampling limits, making wide-band reconstruction possible. Spatially extended sources can also be addressed with C-ESM, although in this case the obtained solution does not recover the spatial extent of the source.

  17. Investigation of an acoustical holography system for real-time imaging

    NASA Astrophysics Data System (ADS)

    Fecht, Barbara A.; Andre, Michael P.; Garlick, George F.; Shelby, Ronald L.; Shelby, Jerod O.; Lehman, Constance D.

    1998-07-01

    A new prototype imaging system based on ultrasound transmission through the object of interest -- acoustical holography -- was developed which incorporates significant improvements in acoustical and optical design. This system is being evaluated for potential clinical application in the musculoskeletal system, interventional radiology, pediatrics, monitoring of tumor ablation, vascular imaging and breast imaging. System limiting resolution was estimated using a line-pair target with decreasing line thickness and equal separation. For a swept frequency beam from 2.6 - 3.0 MHz, the minimum resolution was 0.5 lp/mm. Apatite crystals were suspended in castor oil to approximate breast microcalcifications. Crystals from 0.425 - 1.18 mm in diameter were well resolved in the acoustic zoom mode. Needle visibility was examined with both a 14-gauge biopsy needle and a 0.6 mm needle. The needle tip was clearly visible throughout the dynamic imaging sequence as it was slowly inserted into a RMI tissue-equivalent breast biopsy phantom. A selection of human images was acquired in several volunteers: a 25 year-old female volunteer with normal breast tissue, a lateral view of the elbow joint showing muscle fascia and tendon insertions, and the superficial vessels in the forearm. Real-time video images of these studies will be presented. In all of these studies, conventional sonography was used for comparison. These preliminary investigations with the new prototype acoustical holography system showed favorable results in comparison to state-of-the-art pulse-echo ultrasound and demonstrate it to be suitable for further clinical study. The new patient interfaces will facilitate orthopedic soft tissue evaluation, study of superficial vascular structures and potentially breast imaging.

  18. Transient nearfield acoustic holography based on an interpolated time-domain equivalent source method.

    PubMed

    Zhang, Xiao-Zheng; Bi, Chuan-Xing; Zhang, Yong-Bin; Xu, Liang

    2011-09-01

    Transient nearfield acoustic holography based on an interpolated time-domain equivalent source method (ESM) is proposed to reconstruct transient acoustic fields directly in the time domain. Since the equivalent source strengths solved by the traditional time-domain ESM formulation cannot be used to reconstruct the pressure on the source surface directly, an interpolation function is introduced to develop an interpolated time-domain ESM formulation which permits one to deduce an iterative reconstruction process. As the reconstruction process is ill-conditioned and especially there exists a cumulative effect of errors, the Tikhonov regularization is used to stabilize the process. Numerical examples of reconstructing transient acoustic fields from a baffled planar piston, an impulsively accelerating sphere and a cube box, respectively, demonstrate that the proposed method not only can effectively reconstruct transient acoustic fields in the time domain, but also can visualize acoustic fields in the space domain. And, in the first numerical example, the cumulative effect of errors and the validity of using the Tikhonov regularization to suppress the errors are described.

  19. Reconstruction and separation of vibratory field using structural holography

    NASA Astrophysics Data System (ADS)

    Chesnais, C.; Totaro, N.; Thomas, J.-H.; Guyader, J.-L.

    2017-02-01

    A method for reconstructing and separating vibratory field on a plate-like structure is presented. The method, called ;Structural Holography; is derived from classical Near-field Acoustic Holography (NAH) but in the vibratory domain. In this case, the plate displacement is measured on one-dimensional lines (the holograms) and used to reconstruct the entire two-dimensional displacement field. As a consequence, remote measurements on non directly accessible zones are possible with Structural Holography. Moreover, as it is based on the decomposition of the field into forth and back waves, Structural Holography permits to separate forces in the case of multi-sources excitation. The theoretical background of the Structural Holography method is described first. Then, to illustrate the process and the possibilities of Structural Holography, the academic test case of an infinite plate excited by few point forces is presented. With the principle of vibratory field separation, the displacement fields produced by each point force separately is reconstructed. However, the displacement field is not always meaningful and some additional treatments are mandatory to localize the position of point forces for example. From the simple example of an infinite plate, a post-processing based on the reconstruction of the structural intensity field is thus proposed. Finally, Structural Holography is generalized to finite plates and applied to real experimental measurements

  20. Regularization method for measurement of structural intensity using nearfield acoustical holography.

    PubMed

    Saijyou, Kenji; Okawara, Chiaki

    2005-04-01

    The regularization method for measurement of structural intensity using nearfield acoustical holography is proposed. Spatial derivatives of normal displacement are necessary to obtain the structural intensity. The derivative operations amplify high-wave-number components of measurement noise. Therefore, the estimation of an appropriate wave-number filter is crucial for implementation of the measurement of structural intensity. In conventional methods, this wave-number filter is determined from the flexural wavelength. And the same wave-number filter is applied to obtain all spatial derivatives. As a result, structural intensity obtained from the pressure hologram, whose signal-to-noise ratio is low, is seriously contaminated by the noise. To overcome this difficulty, regularization theory is applied to determine the appropriate wave-number filter for each order of derivatives. The effectiveness of the proposed method is demonstrated by experiments.

  1. Holography: A survey

    NASA Technical Reports Server (NTRS)

    Dudley, D. D.

    1973-01-01

    The development of holography and the state of the art in recording and displaying information, microscopy, motion, pictures, and television applications are discussed. In addition to optical holography, information is presented on microwave, acoustic, ultrasonic, and seismic holography. Other subjects include data processing, data storage, pattern recognition, and computer-generated holography. Diagrams of holographic installations are provided. Photographs of typical holographic applications are used to support the theoretical aspects.

  2. Shape and 3D acoustically induced vibrations of the human eardrum characterized by digital holography

    NASA Astrophysics Data System (ADS)

    Khaleghi, Morteza; Furlong, Cosme; Cheng, Jeffrey Tao; Rosowski, John J.

    2014-07-01

    The eardrum or Tympanic Membrane (TM) transfers acoustic energy from the ear canal (at the external ear) into mechanical motions of the ossicles (at the middle ear). The acousto-mechanical-transformer behavior of the TM is determined by its shape and mechanical properties. For a better understanding of hearing mysteries, full-field-of-view techniques are required to quantify shape, nanometer-scale sound-induced displacement, and mechanical properties of the TM in 3D. In this paper, full-field-of-view, three-dimensional shape and sound-induced displacement of the surface of the TM are obtained by the methods of multiple wavelengths and multiple sensitivity vectors with lensless digital holography. Using our developed digital holographic systems, unique 3D information such as, shape (with micrometer resolution), 3D acoustically-induced displacement (with nanometer resolution), full strain tensor (with nano-strain resolution), 3D phase of motion, and 3D directional cosines of the displacement vectors can be obtained in full-field-ofview with a spatial resolution of about 3 million points on the surface of the TM and a temporal resolution of 15 Hz.

  3. Quantitative measurement of ultrasound pressure field by optical phase contrast method and acoustic holography

    NASA Astrophysics Data System (ADS)

    Oyama, Seiji; Yasuda, Jun; Hanayama, Hiroki; Yoshizawa, Shin; Umemura, Shin-ichiro

    2016-07-01

    A fast and accurate measurement of an ultrasound field with various exposure sequences is necessary to ensure the efficacy and safety of various ultrasound applications in medicine. The most common method used to measure an ultrasound pressure field, that is, hydrophone scanning, requires a long scanning time and potentially disturbs the field. This may limit the efficiency of developing applications of ultrasound. In this study, an optical phase contrast method enabling fast and noninterfering measurements is proposed. In this method, the modulated phase of light caused by the focused ultrasound pressure field is measured. Then, a computed tomography (CT) algorithm used to quantitatively reconstruct a three-dimensional (3D) pressure field is applied. For a high-intensity focused ultrasound field, a new approach that combines the optical phase contrast method and acoustic holography was attempted. First, the optical measurement of focused ultrasound was rapidly performed over the field near a transducer. Second, the nonlinear propagation of the measured ultrasound was simulated. The result of the new approach agreed well with that of the measurement using a hydrophone and was improved from that of the phase contrast method alone with phase unwrapping.

  4. Source characterization of a subsonic jet by using near-field acoustical holography.

    PubMed

    Lee, Moohyung; Bolton, J Stuart

    2007-02-01

    In the present study, patch near-field acoustical holography was used in conjunction with a multireference, cross-spectral sound pressure measurement to visualize the sound field emitted by a subsonic jet and to predict its farfield radiation pattern. A strategy for microphone array design is described that accounts for the low spatial coherence of aeroacoustic sources and for microphone self-noise resulting from entrained flow near the jet. In the experiments, a 0.8-cm-diameter burner was used to produce a subsonic, turbulent jet with a Mach number of 0.26. Six fixed, linear arrays holding eight reference microphones apiece were disposed circumferentially around the jet, and a circular array holding sixteen, equally spaced field microphones was traversed along the jet axis to measure the sound field on a 30-cm-diameter cylindrical surface enclosing the jet. The results revealed that the jet could be modeled as a combination of eleven uncorrelated dipole-, quadrupole-, and octupole-like sources, and the contribution of each source type to the total radiated sound power could be identified. Both the total sound field reconstructed in a three-dimensional space and the farfield radiation directivity obtained by using the latter model were successfully validated by comparisons to directly measured results.

  5. Application of cylindrical near-field acoustical holography to the visualization of aeroacoustic sources.

    PubMed

    Lee, Moohyung; Bolton, J Stuart; Mongeau, Luc

    2003-08-01

    The purpose of this study was to develop methods for visualizing the sound radiation from aeroacoustic sources in order to identify their source strength distribution, radiation patterns, and to quantify the performance of noise control solutions. Here, cylindrical Near-field Acoustical Holography was used for that purpose. In a practical holographic measurement of sources comprising either partially correlated or uncorrelated subsources, it is necessary to use a number of reference microphones so that the sound field on the hologram surface can be decomposed into mutually incoherent partial fields before holographic projection. In this article, procedures are described for determining the number of reference microphones required when visualizing partially correlated aeroacoustic sources; performing source nonstationarity compensation; and applying regularization. The procedures have been demonstrated by application to a ducted fan. Holographic tests were performed to visualize the sound radiation from that source in its original form. The system was then altered to investigate the effect of two modifications on the fan's sound radiation pattern: first, leaks were created in the fan and duct assembly, and second, sound absorbing material was used to line the downstream duct section. Results in all three cases are shown at the blade passing frequency and for a broadband noise component. In the absence of leakage, both components were found to exhibit a dipole-like radiation pattern. Leakage was found to have a strong influence on the directivity of the blade passing tone. The increase of the flow resistance caused by adding the acoustical lining resulted in a nearly symmetric reduction of sound radiation.

  6. Reconstruction of the Acoustic Field Using a Conformal Array

    NASA Technical Reports Server (NTRS)

    Valdivia, Nichlas P.; Williams, Earl G.; Klos, Jacob

    2006-01-01

    Near-field acoustical holography (NAH) requires the measurement of the near-field pressure field over a conformal and closed surface in order to recover the acoustic field on a nearby surface. We are interested in the reconstruction of the acoustic field over the fuselage of a Boeing 757 airplane when pressure data is available over an array of microphones that are conformal to the fuselage surface. In this case the strict NAH theory does not hold, but still there are techniques used to overcome this difficulty. The best known is patch NAH, which has been used for planar surfaces. In this work we will discuss two new techniques used for surfaces with an arbitrarily shape: patch inverse boundary element methods (IBEM) and patch equivalent sources method (ESM). We will discuss the theoretical justification of the method and show reconstructions for in-flight data taken inside a Boeing 757 airplane.

  7. Partial sound field decomposition in multireference near-field acoustical holography by using optimally located virtual references

    NASA Astrophysics Data System (ADS)

    Kim, Yong-Joe; Bolton, J. Stuart; Kwon, Hyu-Sang

    2004-04-01

    It has been shown previously that the multiple reference and field signals recorded during a scanning acoustical holography measurement can be used to decompose the sound field radiated by a composite sound source into mutually incoherent partial fields. To obtain physically meaningful partial fields, i.e., fields closely related to particular component sources, the reference microphones should be positioned as close as possible to the component physical sources that together comprise the complete source. However, it is not always possible either to identify the optimal reference microphone locations prior to performing a holographic measurement, or to place reference microphones at those optimal locations, even if known, owing to physical constraints. Here, post-processing procedures are described that make it possible both to identify the optimal reference microphone locations and to place virtual references at those locations after performing a holographic measurement. The optimal reference microphone locations are defined to be those at which the MUSIC power is maximized in a three-dimensional space reconstructed by holographic projection. The acoustic pressure signals at the locations thus identified can then be used as optimal ``virtual'' reference signals. It is shown through an experiment and numerical simulation that the optimal virtual reference signals can be successfully used to identify physically meaningful partial sound fields, particularly when used in conjunction with partial coherence decomposition procedures.

  8. Violin f-hole contribution to far-field radiation via patch near-field acoustical holography.

    PubMed

    Bissinger, George; Williams, Earl G; Valdivia, Nicolas

    2007-06-01

    The violin radiates either from dual ports (f-holes) or via surface motion of the corpus (top+ribs+back), with no clear delineation between these sources. Combining "patch" near-field acoustical holography over just the f-hole region of a violin with far-field radiativity measurements over a sphere, it was possible to separate f-hole from surface motion contributions to the total radiation of the corpus below 2.6 kHz. A0, the Helmholtz-like lowest cavity resonance, radiated essentially entirely through the f-holes as expected while A1, the first longitudinal cavity mode with a node at the f-holes, had no significant f-hole radiation. The observed A1 radiation comes from an indirect radiation mechanism, induced corpus motion approximately mirroring the cavity pressure profile seen for violinlike bowed string instruments across a wide range of sizes. The first estimates of the fraction of radiation from the f-holes F(f) indicate that some low frequency corpus modes thought to radiate only via surface motion (notably the first corpus bending modes) had significant radiation through the f-holes, in agreement with net volume changes estimated from experimental modal analysis. F(f) generally trended lower with increasing frequency, following corpus mobility decreases. The f-hole directivity (top/back radiativity ratio) was generally higher than whole-violin directivity.

  9. Characterization of a multi-element clinical HIFU system using acoustic holography and nonlinear modeling.

    PubMed

    Kreider, Wayne; Yuldashev, Petr V; Sapozhnikov, Oleg A; Farr, Navid; Partanen, Ari; Bailey, Michael R; Khokhlova, Vera A

    2013-08-01

    High-intensity focused ultrasound (HIFU) is a treatment modality that relies on the delivery of acoustic energy to remote tissue sites to induce thermal and/or mechanical tissue ablation. To ensure the safety and efficacy of this medical technology, standard approaches are needed for accurately characterizing the acoustic pressures generated by clinical ultrasound sources under operating conditions. Characterization of HIFU fields is complicated by nonlinear wave propagation and the complexity of phased-array transducers. Previous work has described aspects of an approach that combines measurements and modeling, and here we demonstrate this approach for a clinical phased-array transducer. First, low amplitude hydrophone measurements were performed in water over a scan plane between the array and the focus. Second, these measurements were used to holographically reconstruct the surface vibrations of the transducer and to set a boundary condition for a 3-D acoustic propagation model. Finally, nonlinear simulations of the acoustic field were carried out over a range of source power levels. Simulation results were compared with pressure waveforms measured directly by hydrophone at both low and high power levels, demonstrating that details of the acoustic field, including shock formation, are quantitatively predicted.

  10. Characterization of a Multi-element Clinical HIFU System Using Acoustic Holography and Nonlinear Modeling

    PubMed Central

    Kreider, Wayne; Yuldashev, Petr V.; Sapozhnikov, Oleg A.; Farr, Navid; Partanen, Ari; Bailey, Michael R.; Khokhlova, Vera A.

    2014-01-01

    High-intensity focused ultrasound (HIFU) is a treatment modality that relies on the delivery of acoustic energy to remote tissue sites to induce thermal and/or mechanical tissue ablation. To ensure the safety and efficacy of this medical technology, standard approaches are needed for accurately characterizing the acoustic pressures generated by clinical ultrasound sources under operating conditions. Characterization of HIFU fields is complicated by nonlinear wave propagation and the complexity of phased-array transducers. Previous work has described aspects of an approach that combines measurements and modeling, and here we demonstrate this approach for a clinical phased array transducer. First, low-amplitude hydrophone measurements were performed in water over a scan plane between the array and the focus. Second, these measurements were used to holographically reconstruct the surface vibrations of the transducer and to set a boundary condition for a 3-D acoustic propagation model. Finally, nonlinear simulations of the acoustic field were carried out over a range of source power levels. Simulation results were compared to pressure waveforms measured directly by hydrophone at both low and high power levels, demonstrating that details of the acoustic field including shock formation are quantitatively predicted. PMID:25004539

  11. Krylov subspace iterative methods for boundary element method based near-field acoustic holography.

    PubMed

    Valdivia, Nicolas; Williams, Earl G

    2005-02-01

    The reconstruction of the acoustic field for general surfaces is obtained from the solution of a matrix system that results from a boundary integral equation discretized using boundary element methods. The solution to the resultant matrix system is obtained using iterative regularization methods that counteract the effect of noise on the measurements. These methods will not require the calculation of the singular value decomposition, which can be expensive when the matrix system is considerably large. Krylov subspace methods are iterative methods that have the phenomena known as "semi-convergence," i.e., the optimal regularization solution is obtained after a few iterations. If the iteration is not stopped, the method converges to a solution that generally is totally corrupted by errors on the measurements. For these methods the number of iterations play the role of the regularization parameter. We will focus our attention to the study of the regularizing properties from the Krylov subspace methods like conjugate gradients, least squares QR and the recently proposed Hybrid method. A discussion and comparison of the available stopping rules will be included. A vibrating plate is considered as an example to validate our results.

  12. Analyzing panel acoustic contributions toward the sound field inside the passenger compartment of a full-size automobile.

    PubMed

    Wu, Sean F; Moondra, Manmohan; Beniwal, Ravi

    2015-04-01

    The Helmholtz equation least squares (HELS)-based nearfield acoustical holography (NAH) is utilized to analyze panel acoustic contributions toward the acoustic field inside the interior region of an automobile. Specifically, the acoustic power flows from individual panels are reconstructed, and relative contributions to sound pressure level and spectrum at any point of interest are calculated. Results demonstrate that by correlating the acoustic power flows from individual panels to the field acoustic pressure, one can correctly locate the panel allowing the most acoustic energy transmission into the vehicle interior. The panel on which the surface acoustic pressure amplitude is the highest should not be used as indicative of the panel responsible for the sound field in the vehicle passenger compartment. Another significant advantage of this HELS-based NAH is that measurements of the input data only need to be taken once by using a conformal array of microphones in the near field, and ranking of panel acoustic contributions to any field point can be readily performed. The transfer functions between individual panels of any vibrating structure to the acoustic pressure anywhere in space are calculated not measured, thus significantly reducing the time and effort involved in panel acoustic contributions analyses.

  13. Compressive Holography

    NASA Astrophysics Data System (ADS)

    Lim, Se Hoon

    Compressive holography estimates images from incomplete data by using sparsity priors. Compressive holography combines digital holography and compressive sensing. Digital holography consists of computational image estimation from data captured by an electronic focal plane array. Compressive sensing enables accurate data reconstruction by prior knowledge on desired signal. Computational and optical co-design optimally supports compressive holography in the joint computational and optical domain. This dissertation explores two examples of compressive holography: estimation of 3D tomographic images from 2D data and estimation of images from under sampled apertures. Compressive holography achieves single shot holographic tomography using decompressive inference. In general, 3D image reconstruction suffers from underdetermined measurements with a 2D detector. Specifically, single shot holographic tomography shows the uniqueness problem in the axial direction because the inversion is ill-posed. Compressive sensing alleviates the ill-posed problem by enforcing some sparsity constraints. Holographic tomography is applied for video-rate microscopic imaging and diffuse object imaging. In diffuse object imaging, sparsity priors are not valid in coherent image basis due to speckle. So incoherent image estimation is designed to hold the sparsity in incoherent image basis by support of multiple speckle realizations. High pixel count holography achieves high resolution and wide field-of-view imaging. Coherent aperture synthesis can be one method to increase the aperture size of a detector. Scanning-based synthetic aperture confronts a multivariable global optimization problem due to time-space measurement errors. A hierarchical estimation strategy divides the global problem into multiple local problems with support of computational and optical co-design. Compressive sparse aperture holography can be another method. Compressive sparse sampling collects most of significant field

  14. Thermodynamic holography

    NASA Astrophysics Data System (ADS)

    Wei, Bo-Bo; Jiang, Zhan-Feng; Liu, Ren-Bao

    2015-10-01

    The holographic principle states that the information about a volume of a system is encoded on the boundary surface of the volume. Holography appears in many branches of physics, such as optics, electromagnetism, many-body physics, quantum gravity, and string theory. Here we show that holography is also an underlying principle in thermodynamics, a most important foundation of physics. The thermodynamics of a system is fully determined by its partition function. We prove that the partition function of a finite but arbitrarily large system is an analytic function on the complex plane of physical parameters, and therefore the partition function in a region on the complex plane is uniquely determined by its values along the boundary. The thermodynamic holography has applications in studying thermodynamics of nano-scale systems (such as molecule engines, nano-generators and macromolecules) and provides a new approach to many-body physics.

  15. Seismic Holography of Solar Activity

    NASA Technical Reports Server (NTRS)

    Lindsey, Charles

    2000-01-01

    The basic goal of the project was to extend holographic seismic imaging techniques developed under a previous NASA contract, and to incorporate phase diagnostics. Phase-sensitive imaging gives us a powerful probe of local thermal and Doppler perturbations in active region subphotospheres, allowing us to map thermal structure and flows associated with "acoustic moats" and "acoustic glories". These remarkable features were discovered during our work, by applying simple acoustic power holography to active regions. Included in the original project statement was an effort to obtain the first seismic images of active regions on the Sun's far surface.

  16. Novel Acoustic Scattering Processes for Target Discrimination

    DTIC Science & Technology

    2007-09-30

    acoustic signal using algorithms originally developed for high-frequency acoustical holography [11]. Data is only acquired by scanning a hydrophone ...by the application of a back-propagation algorithm based on the methods of acoustic holography . Selected results relevant to the interpretation of...Novel Acoustic Scattering Processes for Target Discrimination Philip L. Marston Physics and Astronomy Dept., Washington State University, Pullman

  17. Novel Acoustic Scattering Processes for Target Discrimination

    DTIC Science & Technology

    2006-09-30

    based on acoustic holography algorithms): It has been possible to form images from data acquired as noted in item (2) by the application of a back...propagation algorithm based on the methods of acoustic holography . Selected results relevant to the interpretation of Bistatic SAS images are noted...to back-propagate the sampled acoustic signal using algorithms originally developed for high-frequency acoustical holography [10]. Data is only

  18. Dental Holography

    NASA Astrophysics Data System (ADS)

    Dirtoft, Ingegerd

    1983-12-01

    Ten years have passed since the first articles appeared in this new field. The qualities of the laser light together with the need of contactless 3-D measurements for different dental purposes seemed to be extremely promising, but still just a few scientists have used the method and mostly for laboratory studies. For some reason there has been a preponderance for orthodontic measurements. This seems to be a bit peculiar from holographic view compared with measurements for engineering purposes, which usually are made on metals. So naturally holography can become a clinical tool for measurements in the field of fixed bridges, removable partial dentures and implants. One of the problems is that the need for holography in dental research must be fulfilled in collaboration with physicists. Only a two-way communication during an entire experiment can balance both technical and odontological demands and thus give practical and clinical important results. The need for an easy way of handling the evaluation to get all required information is another problem and of course the holographic equipment must be converted to a box easy to handle for everyone. At last the position of dental holography today is going to be carefully examined together with an attempt to look into the hopefully exciting and not to utopic future for this research field.

  19. Combined Helmholtz equation-least squares method for reconstructing acoustic radiation from arbitrarily shaped objects

    NASA Astrophysics Data System (ADS)

    Wu, Sean F.; Zhao, Xiang

    2002-07-01

    A combined Helmholtz equation-least squares (CHELS) method is developed for reconstructing acoustic radiation from an arbitrary object. This method combines the advantages of both the HELS method and the Helmholtz integral theory based near-field acoustic holography (NAH). As such it allows for reconstruction of the acoustic field radiated from an arbitrary object with relatively few measurements, thus significantly enhancing the reconstruction efficiency. The first step in the CHELS method is to establish the HELS formulations based on a finite number of acoustic pressure measurements taken on or beyond a hypothetical spherical surface that encloses the object under consideration. Next enough field acoustic pressures are generated using the HELS formulations and taken as the input to the Helmholtz integral formulations implemented through the boundary element method (BEM). The acoustic pressure and normal component of the velocity at the discretized nodes on the surface are then determined by solving two matrix equations using singular value decomposition (SVD) and regularization techniques. Also presented are in-depth analyses of the advantages and limitations of the CHELS method. Examples of reconstructing acoustic radiation from separable and nonseparable surfaces are demonstrated. copyright 2002 Acoustical Society of America.

  20. Incoherent holography

    NASA Astrophysics Data System (ADS)

    Abramson, Nils H.

    2000-10-01

    Dennis Gabor invented in-line holography in 1947, but at that time the coherent light from a laser did not yet exist and therefore the holograms he produced were of very low quality. When the laser was born in 1960 beautiful 3-D off- center holograms were for the first time produced by Emmett Leith and Juris Upatnieks. However, already as early as 1934 the inventor and artist Hans Weil patented a method to produce simple pictures that appeared floating in space, by scratching a transparent or metallic surface in certain directions. In 1995 William J. Beaty published a method for Hand-Drawn Holograms. Then it became possible for any artist to draw his own 3-D pictures of simple objects and using his ingenious techniques these hand drawn images will mimic many of the qualities of ordinary holograms.

  1. Emerging holography

    SciTech Connect

    Erlich, Joshua; Kribs, Graham D.; Low, Ian

    2006-05-01

    We rederive AdS/CFT predictions for infrared two-point functions by an entirely four-dimensional approach, without reference to holography. This approach, originally due to Migdal in the context of QCD, utilizes an extrapolation from the ultraviolet to the infrared using a Pade approximation of the two-point function. We show that the Pade approximation and AdS/CFT give the same leading order predictions, and we discuss including power corrections such as those due to condensates of gluons and quarks in QCD. At finite order the Pade approximation provides a gauge invariant regularization of a higher dimensional gauge theory in the spirit of deconstructed extra dimensions. The radial direction of anti-de Sitter space emerges naturally in this approach.

  2. Holography and tomography

    SciTech Connect

    Howells, M.

    1997-02-01

    This session includes a collection of outlines of pertinent information, diagrams, graphs, electron micrographs, and color photographs pertaining to historical aspects and recent advances in the development of X-ray Gabor Holography. Many of the photographs feature or pertain to instrumentation used in holography, tomography, and cryo-holography.

  3. Combined Helmholtz equation-least squares method for reconstructing acoustic radiation from arbitrarily shaped objects.

    PubMed

    Wu, Sean F; Zhao, Xiang

    2002-07-01

    A combined Helmholtz equation-least squares (CHELS) method is developed for reconstructing acoustic radiation from an arbitrary object. This method combines the advantages of both the HELS method and the Helmholtz integral theory based near-field acoustic holography (NAH). As such it allows for reconstruction of the acoustic field radiated from an arbitrary object with relatively few measurements, thus significantly enhancing the reconstruction efficiency. The first step in the CHELS method is to establish the HELS formulations based on a finite number of acoustic pressure measurements taken on or beyond a hypothetical spherical surface that encloses the object under consideration. Next enough field acoustic pressures are generated using the HELS formulations and taken as the input to the Helmholtz integral formulations implemented through the boundary element method (BEM). The acoustic pressure and normal component of the velocity at the discretized nodes on the surface are then determined by solving two matrix equations using singular value decomposition (SVD) and regularization techniques. Also presented are in-depth analyses of the advantages and limitations of the CHELS method. Examples of reconstructing acoustic radiation from separable and nonseparable surfaces are demonstrated.

  4. Guest Editoria Holography A Dedication To Dennis Gabor

    NASA Astrophysics Data System (ADS)

    Wyant, James C.; Chen, Chungte T.; Reynolds, George O.

    1980-10-01

    We thought it was time to bring the readers of Optical Engineering up to date on the new developments in holography, as was done exactly five years ago with the September/October 1975 special issue. The seeds for this special issue were sown during the 1978 Gordon Conference on Coherent Optics and Holography held at the Miramar Hotel in Santa Barbara, California. The conference clearly demonstrated, through the discussion of many interesting research and development applications, that holography is alive and well. For example, artists have discovered holography as a new medium and there is a museum for displaying new holographic developments and inventions. In addition to the opening of the New York museum where artists and patrons are thoroughly enjoying holography, the past five years have witnessed the publication of the Handbook of Optical Holography, continuing issues of the Acoustical Holography proceedings, the gathering of scientists to exchange ideas at three Gordon Conferences in 1976, 1978, and 1980, and the SPIE conference on holography held in Los Angeles in February 1980.

  5. 48 Years with holography

    NASA Astrophysics Data System (ADS)

    Kubota, Toshihiro

    2014-11-01

    The invention of holography was epoch-making in optics. Although the research on holography has cycled through active and stagnant periods, holography has gradually become a practical technique thanks to researchers' steady efforts. The technique has many attractive features and is used in many fields nowadays. The latest developments in high-definition image sensors and ultrashort pulsed lasers have given rise to a new possibility of holography. I have been engaged in the research and development of holography since I knew it by casual opportunity. In this paper, the research in early stages of holography is briefly described, and some of my basic and applied research in which I have so far engaged are introduced.

  6. Predictive dynamic digital holography

    NASA Astrophysics Data System (ADS)

    Sulaiman, Sennan; Gibson, Steve; Spencer, Mark

    2016-09-01

    Digital holography has received recent attention for many imaging and sensing applications, including imaging through turbulent and turbid media, adaptive optics, three dimensional projective display technology and optical tweezing. A significant obstacle for digital holography in real-time applications, such as wavefront sensing for high energy laser systems and high speed imaging for target tracking, is the fact that digital holography is computationally intensive; it requires iterative virtual wavefront propagation and hill-climbing to optimize some sharpness criteria. This paper demonstrates real-time methods for digital holography based on approaches developed recently at UCLA for optimal and adaptive identification, prediction, and control of optical wavefronts. The methods presented integrate minimum variance wavefront prediction into digital holography schemes to short-circuit the computationally intensive algorithms for iterative propagation of virtual wavefronts and hill climbing for sharpness optimization.

  7. Artistic Representation with Pulsed Holography

    NASA Astrophysics Data System (ADS)

    Ishii, S.

    2013-02-01

    This thesis describes artistic representation through pulsed holography. One of the prevalent practical problems in making holograms is object movement. Any movement of the object or film, including movement caused by acoustic vibration, has the same fatal results. One way of reducing the chance of movement is by ensuring that the exposure is very quick; using a pulsed laser can fulfill this objective. The attractiveness of using pulsed laser is based on the variety of materials or objects that can be recorded (e.g., liquid material or instantaneous scene of a moving object). One of the most interesting points about pulsed holograms is that some reconstructed images present us with completely different views of the real world. For example, the holographic image of liquid material does not appear fluid; it looks like a piece of hard glass that would produce a sharp sound upon tapping. In everyday life, we are unfamiliar with such an instantaneous scene. On the other hand, soft-textured materials such as a feather or wool differ from liquids when observed through holography. Using a pulsed hologram, we can sense the soft touch of the object or material with the help of realistic three-dimensional (3-D) images. The images allow us to realize the sense of touch in a way that resembles touching real objects. I had the opportunity to use a pulsed ruby laser soon after I started to work in the field of holography in 1979. Since then, I have made pulsed holograms of activities, including pouring water, breaking eggs, blowing soap bubbles, and scattering feathers and popcorn. I have also created holographic art with materials and objects, such as silk fiber, fabric, balloons, glass, flowers, and even the human body. Whenever I create art, I like to present the spectator with a new experience in perception. Therefore, I would like to introduce my experimental artwork through those pulsed holograms.

  8. Characterization of Transducer Performance and Narrowband Transient Ultrasonic Fields in Metals by Rayleigh-Sommerfeld Backpropagation of Compression Acoustic Waves Measured with Double-Pulsed Tv Holography

    NASA Astrophysics Data System (ADS)

    Trillo, Cristina; Doval, Ángel F.; Fernández, José L.; Rodríguez-Gómez, Pablo; López-Vázquez, J. Carlos

    2014-10-01

    This article presents a method aimed at the characterization of the narrowband transient acoustic field radiated by an ultrasonic plane transducer into a homogeneous, isotropic and optically opaque prismatic solid, and the assessment of the performance of the acoustic source. The method relies on a previous technique based on the full-field optical measurement of an acoustic wavepacket at the surface of a solid and its subsequent numerical backpropagation within the material. The experimental results show that quantitative transversal and axial profiles of the complex amplitude of the beam can be obtained at any plane between the measurement and excitation surfaces. The reconstruction of the acoustic field at the transducer face, carried out on a defective transducer model, shows that the method could also be suitable for the nondestructive testing of the performance of ultrasonic sources. In all cases, the measurements were performed with the transducer working under realistic loading conditions.

  9. An Introduction to Educational Holography.

    ERIC Educational Resources Information Center

    Lloyd, R. Scott

    Holograms are capable of taking the two-dimensional ways of envisioning information to another dimension of presentation, representation, and conceptualization. Educational holography is joining display holography, holographic testing of materials, and holographic optical elements as a fourth major field in holography. Holograms are explored as…

  10. Holography and Optical Storage

    NASA Astrophysics Data System (ADS)

    Imlau, Mirco; Fally, Martin; Burr, Geoffrey W.; Sincerbox, Glenn T.

    The term holography is composed of the Greek words holos (= whole) and graphein (= to record, to write), and thus summarizes the key aspects of its underlying principle: recording the complete wavefront of an object, i.e., its intensity as well as its phase. Interference and diffraction phenomena are employed to record and retrieve the full information, a technique pioneered by Dennis Gabor in 1948. He was honored with the Nobel prize in Physics in 1971, reflecting the general impact of holography on modern physics.

  11. Acoustics

    NASA Technical Reports Server (NTRS)

    Goodman, Jerry R.; Grosveld, Ferdinand

    2007-01-01

    The acoustics environment in space operations is important to maintain at manageable levels so that the crewperson can remain safe, functional, effective, and reasonably comfortable. High acoustic levels can produce temporary or permanent hearing loss, or cause other physiological symptoms such as auditory pain, headaches, discomfort, strain in the vocal cords, or fatigue. Noise is defined as undesirable sound. Excessive noise may result in psychological effects such as irritability, inability to concentrate, decrease in productivity, annoyance, errors in judgment, and distraction. A noisy environment can also result in the inability to sleep, or sleep well. Elevated noise levels can affect the ability to communicate, understand what is being said, hear what is going on in the environment, degrade crew performance and operations, and create habitability concerns. Superfluous noise emissions can also create the inability to hear alarms or other important auditory cues such as an equipment malfunctioning. Recent space flight experience, evaluations of the requirements in crew habitable areas, and lessons learned (Goodman 2003; Allen and Goodman 2003; Pilkinton 2003; Grosveld et al. 2003) show the importance of maintaining an acceptable acoustics environment. This is best accomplished by having a high-quality set of limits/requirements early in the program, the "designing in" of acoustics in the development of hardware and systems, and by monitoring, testing and verifying the levels to ensure that they are acceptable.

  12. Holography: science and art

    NASA Astrophysics Data System (ADS)

    Boone, Pierre M.

    1998-09-01

    Art and science are separated by a very large distance nowadays. Long ago, e.g. in Renaissance, or even earlier, in classic Greece and Rome, or still earlier in Egypt or Mesopotamia, arts and sciences were united. Today they seem to go separate paths: science for the industry, arts for the gallery. Holography is an exception: no art without science, but also no science without art.

  13. Dynamic holography using pixelated light modulators.

    PubMed

    Zwick, Susanne; Haist, Tobias; Warber, Michael; Osten, Wolfgang

    2010-09-01

    Dynamic holography using spatial light modulators is a very flexible technique that offers various new applications compared to static holography. We give an overview on the technical background of dynamic holography focusing on pixelated spatial light modulators and their technical restrictions, and we present a selection of the numerous applications of dynamic holography.

  14. Holography in the Junior High.

    ERIC Educational Resources Information Center

    Tomaszkiewicz, Frank

    1988-01-01

    Examines the use of holography in the art technology program of a junior high school. Characterizing holography as a valuable artistic experience and discovery experience and stressing the importance of student interest and involvement, the author discusses the necessary equipment for the project and includes two diagrams of a holographic setup.…

  15. Acoustic Intensity Measurements in the Presence of Low Mach Number Flow

    DTIC Science & Technology

    1993-09-01

    broadband acoustic holography ,3 intensity measurements in the presence of flow,"𔄁𔄀. 7 in-situ evaluation of the acoustic impedance and sound absorption...Cross Spectra" Ph.D. Thesis, Catholic University, (1987). 3. Loyau, T., Pascal, J., Gaillard, P., "Broadband Acoustic Holography Reconstruction From...AD-A269 995 The Pennsylvania State University APPLIED RESEARCH LABORATORY P.O. Box 30 State College, PA 16804 ACOUSTIC INTENSITY MEASUREMENTS IN THE

  16. Generalized phase-shifting color digital holography

    NASA Astrophysics Data System (ADS)

    Nomura, Takanori; Kawakami, Takaaki; Shinomura, Kazuma

    2016-06-01

    Two methods to apply the generalized phase-shifting digital holography to color digital holography are proposed. One is wave-splitting generalized phase-shifting color digital holography. This is realized by using a color Bayer camera. Another is multiple exposure generalized phase-shifting color digital holography. This is realized by the wavelength-dependent phase-shifting devices. Experimental results for both generalized phase-shifting color digital holography are presented to confirm the proposed methods.

  17. Tracking Energy Flow Using a Volumetric Acoustic Intensity Imager (VAIM)

    NASA Technical Reports Server (NTRS)

    Klos, Jacob; Williams, Earl G.; Valdivia, Nicolas P.

    2006-01-01

    A new measurement device has been invented at the Naval Research Laboratory which images instantaneously the intensity vector throughout a three-dimensional volume nearly a meter on a side. The measurement device consists of a nearly transparent spherical array of 50 inexpensive microphones optimally positioned on an imaginary spherical surface of radius 0.2m. Front-end signal processing uses coherence analysis to produce multiple, phase-coherent holograms in the frequency domain each related to references located on suspect sound sources in an aircraft cabin. The analysis uses either SVD or Cholesky decomposition methods using ensemble averages of the cross-spectral density with the fixed references. The holograms are mathematically processed using spherical NAH (nearfield acoustical holography) to convert the measured pressure field into a vector intensity field in the volume of maximum radius 0.4 m centered on the sphere origin. The utility of this probe is evaluated in a detailed analysis of a recent in-flight experiment in cooperation with Boeing and NASA on NASA s Aries 757 aircraft. In this experiment the trim panels and insulation were removed over a section of the aircraft and the bare panels and windows were instrumented with accelerometers to use as references for the VAIM. Results show excellent success at locating and identifying the sources of interior noise in-flight in the frequency range of 0 to 1400 Hz. This work was supported by NASA and the Office of Naval Research.

  18. Adaptive Optical Scanning Holography

    PubMed Central

    Tsang, P. W. M.; Poon, Ting-Chung; Liu, J.-P.

    2016-01-01

    Optical Scanning Holography (OSH) is a powerful technique that employs a single-pixel sensor and a row-by-row scanning mechanism to capture the hologram of a wide-view, three-dimensional object. However, the time required to acquire a hologram with OSH is rather lengthy. In this paper, we propose an enhanced framework, which is referred to as Adaptive OSH (AOSH), to shorten the holographic recording process. We have demonstrated that the AOSH method is capable of decreasing the acquisition time by up to an order of magnitude, while preserving the content of the hologram favorably. PMID:26916866

  19. Femtosecond spectral holography

    NASA Astrophysics Data System (ADS)

    Weiner, Andrew M.; Leaird, Daniel E.; Reitze, David H.; Paek, Eung G.

    1992-10-01

    Storage, recall, and processing of shaped femtosecond waveforms are achieved by performing spectral holography within a femtosecond pulse shaping apparatus. Time reversal, as well as correlation and convolution, of femtosecond temporal signals is demonstrated. Applications of this technique to matched filtering, dispersion compensation, encryption and decoding, and femtosecond waveform synthesis are also discussed. The work extends the powerful principles of holographic signal processing, which have been used extensively for pattern recognition and filtering of two-dimensional spatial signals, to the femtosecond time domain.

  20. Femtosecond spectral holography

    SciTech Connect

    Weiner, A.M.; Leaird, D.E.; Reitze, D.H.; Paek, E.G. )

    1992-10-01

    Storage, recall, and processing of shaped femtosecond waveforms are achieved by performing spectral holography within a femtosecond pulse shaping apparatus. Time reversal, as well as correlation and convolution, of femtosecond temporal signals is demonstrated. Applications of this technique to matched filtering, dispersion compensation, encryption and decoding, and femtosecond waveform synthesis are also discussed. The work extends the powerful principles of holographic signal processing, which have been used extensively for pattern recognition and filtering of two-dimensional spatial signals, to the femtosecond time domain. 44 refs.

  1. Adaptive Optical Scanning Holography

    NASA Astrophysics Data System (ADS)

    Tsang, P. W. M.; Poon, Ting-Chung; Liu, J.-P.

    2016-02-01

    Optical Scanning Holography (OSH) is a powerful technique that employs a single-pixel sensor and a row-by-row scanning mechanism to capture the hologram of a wide-view, three-dimensional object. However, the time required to acquire a hologram with OSH is rather lengthy. In this paper, we propose an enhanced framework, which is referred to as Adaptive OSH (AOSH), to shorten the holographic recording process. We have demonstrated that the AOSH method is capable of decreasing the acquisition time by up to an order of magnitude, while preserving the content of the hologram favorably.

  2. Holography gets smart

    NASA Astrophysics Data System (ADS)

    Lowe, Chris; Larbey, Cynthia

    2008-02-01

    At least 6% of world trade, amounting to some 200bn per year, involves counterfeit goods. But this figure would be even higher were it not for the humble hologram. Invented 50 years ago, holograms provide authentication tags to deter copying, and can be found everywhere from credit cards, passports and banknotes to consumer goods, cosmetics and pharmaceuticals. Holography also underpins supermarket scanners and CD players; it can even be used to store optical data in 3D. Now, however, holograms are making their mark as powerful yet cheap diagnostic tools, which could in particular have many applications in biomedicine.

  3. Split-illumination electron holography

    SciTech Connect

    Tanigaki, Toshiaki; Aizawa, Shinji; Suzuki, Takahiro; Park, Hyun Soon; Inada, Yoshikatsu; Matsuda, Tsuyoshi; Taniyama, Akira; Shindo, Daisuke; Tonomura, Akira

    2012-07-23

    We developed a split-illumination electron holography that uses an electron biprism in the illuminating system and two biprisms (applicable to one biprism) in the imaging system, enabling holographic interference micrographs of regions far from the sample edge to be obtained. Using a condenser biprism, we split an electron wave into two coherent electron waves: one wave is to illuminate an observation area far from the sample edge in the sample plane and the other wave to pass through a vacuum space outside the sample. The split-illumination holography has the potential to greatly expand the breadth of applications of electron holography.

  4. Pre-holography

    SciTech Connect

    Kay, Bernard S.; Larkin, Peter

    2008-06-15

    We construct a symplectic isomorphism h from classical Klein Gordon solutions of mass m on (d+1)-dimensional Lorentzian anti-de Sitter space (equipped with the usual symplectic form) to a certain symplectic space of functions on its conformal boundary (only) for all integer and half-integer {delta} (=(d/2)+(1/2)(d{sup 2}+4m{sup 2}){sup 1/2}). h induces a large family of new examples of Rehren's algebraic holography in which the net of local quantum Klein Gordon algebras in AdS is seen to map to a suitably defined net of local algebras for the (generalized free) scalar conformal field with anomalous dimension {delta} on d-dimensional Minkowski space (the AdS boundary). Relatedly, we show for these models that Bertola et al.'s boundary-limit holography becomes a quantum duality (only) if the test functions for boundary Wightman distributions are restricted in a particular way.

  5. Tailoring ultrasonic beams with optoacoustic holography

    NASA Astrophysics Data System (ADS)

    Meyer, Alex; Gspan, Stefan J.; Bernet, Stefan; Ritsch-Marte, Monika

    2003-06-01

    A combination of laser-induced ultrasound generation and ultrasonic holography for spatial control of the generated ultrasonic pulse is presented. Ultrasound is produced by absorption of laser pulses at an absorbing layer in a water tank via the optoacoustic effect. In order to produce a defined ultrasonic frequency in the MHz range, the laser pulses are harmonically time-modulated using an acousto-optic modulator (AOM). Additionally, the laser intensity is spatially controlled. This is realized with a high resolution liquid crystal spatial light modulator (LCD). A computer generated pattern is displayed at the LCD and projected by the expanded laser beam to an absorptive layer in the water tank. As a result, the emitted ultrasonic wave emerges in a predetermined way, which is an acoustical analogue to the effect of a "diffractive optical element" in laser optics. The flexible method of optical ultrasound generation and diffractive steering promises new applications in medical and technical ultrasound diagnostics.

  6. Atomic resolution holography.

    PubMed

    Hayashi, Kouichi

    2014-11-01

    Atomic resolution holography, such as X-ray fluorescence holography (XFH)[1] and photoelectron holography (PH), has the attention of researcher as an informative local structure analysis, because it provides three dimensional atomic images around specific elements within a range of a few nanometers. It can determine atomic arrangements around a specific element without any prior knowledge of structures. It is considered that the atomic resolution holographic is a third method of structural analysis at the atomic level after X-ray diffraction (XRD) and X-ray absorption fine structure (XAFS). As known by many researchers, XRD and XAFS are established methods that are widespread use in various fields. XRD and XAFS provide information on long-range translational periodicities and very local environments, respectively, whereas the atomic resolution holography gives 3D information on the local order and can visualize surrounding atoms with a large range of coordination shells. We call this feature "3D medium-range local structure observation".In addition to this feature, the atomic resolution holography is very sensitive to the displacement of atoms from their ideal positions, and one can obtain quantitative information about local lattice distortions by analyzing reconstructed atomic images[2] When dopants with different atomic radii from the matrix elements are present, the lattices around the dopants are distorted. However, using the conventional methods of structural analysis, one cannot determine the extent to which the local lattice distortions are preserved from the dopants. XFH is a good tool for solving this problem.Figure 1 shows a recent achievement on a relaxor ferroelectric of Pb(Mg1/3Nb2/3)O3 (PMN) using XFH. The structural studies of relaxor ferroelectrics have been carried out by X-ray or neutron diffractions, which suggested rhombohedral distortions of their lattices. However, their true pictures have not been obtained, yet. The Nb Kα holograms showed

  7. Vibration testing and analysis using holography

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Time average holography is useful in recording steady state vibrational mode patterns. Phase relationships under steady state conditions are measured with real time holography and special phase shifting techniques. Data from Michelson interferometer verify vibration amplitudes from holographic data.

  8. Mathematical refocusing of images in electronic holography

    SciTech Connect

    Stetson, Karl A.

    2009-07-01

    This paper presents an illustration of mathematical refocusing of images obtained by the HoloFringe300K electronic holography program. The purpose is to demonstrate that this form of electronic holography is equivalent to image-plane, phase-stepped digital holography. The mathematical refocusing method used here differs from those in common use and may have some advantages.

  9. Holography inspired stringy hadrons

    NASA Astrophysics Data System (ADS)

    Sonnenschein, Jacob

    2017-01-01

    Holography inspired stringy hadrons (HISH) is a set of models that describe hadrons: mesons, baryons and glueballs as strings in flat four dimensional space-time. The models are based on a "map" from stringy hadrons of holographic confining backgrounds. In this note we review the "derivation" of the models. We start with a brief reminder of the passage from the AdS5 ×S5 string theory to certain flavored confining holographic models. We then describe the string configurations in holographic backgrounds that correspond to a Wilson line, a meson, a baryon and a glueball. The key ingredients of the four dimensional picture of hadrons are the "string endpoint mass" and the "baryonic string vertex". We determine the classical trajectories of the HISH. We review the current understanding of the quantization of the hadronic strings. We end with a summary of the comparison of the outcome of the HISH models with the PDG data about mesons and baryons. We extract the values of the tension, masses and intercepts from best fits, write down certain predictions for higher excited hadrons and present attempts to identify glueballs.

  10. Industrial Application Of Instant Holography

    NASA Astrophysics Data System (ADS)

    Schorner, J.; Rottenkolber, H.

    1983-10-01

    The development of holographic test methods has lead to a wide industrial application. Today serial tests of aircraft tyres with holography have become routine. A large chemical company is testing their plastic materials like tanks, wheels and fans with the method of holographic interferometry. In the power engine industry turbine blades are tested holographically to find an optimal shape and to test the vibration behaviour. The automotive industry is using holographic methods' for construction optimization. The economic application of these test methods was possible by using instant holography. The principle of a new hologramrecorder is presented. The application of this equipment is shown in examples of testing materials, optimizing constructions and vibration analysis.

  11. Green light for pulsed holography

    NASA Astrophysics Data System (ADS)

    Olson, Bernadette L.; Olson, Ron B.; Hess, Robert A.

    1993-03-01

    This paper reviews the historical reasons why so few neodymium:yttrium aluminum garnet (Nd:YAG) lasers are dedicated to display holography in comparison to ruby lasers, why positive light holographics (PLH) decided to use an Nd:YAG/Nd:Glass laser and what kind of configuration is used. A practical overview on how to use an Nd:YAG/Nd:Glass laser for deep-image holography is discussed, and an evaluation of the transmission holograms recorded with an Nd:YAG/Nd:Glass laser is made in particular from an image planing point of view.

  12. Holography with a neutron interferometer.

    PubMed

    Sarenac, Dusan; Huber, Michael G; Heacock, Benjamin; Arif, Muhammad; Clark, Charles W; Cory, David G; Shahi, Chandra B; Pushin, Dmitry A

    2016-10-03

    We use a Mach-Zehnder interferometer to perform neutron holography of a spiral phase plate. The object beam passes through a spiral phase plate, acquiring the phase twist characteristic of orbital angular momentum states. The reference beam passes through a fused silica prism, acquiring a linear phase gradient. The resulting hologram is a fork dislocation image, which could be used to reconstruct neutron beams with various orbital angular momenta. This work paves the way for novel applications of neutron holography, diffraction and imaging.

  13. Hybridization approach to in-line and off-axis (electron) holography for superior resolution and phase sensitivity

    PubMed Central

    Ozsoy-Keskinbora, C.; Boothroyd, C. B.; Dunin-Borkowski, R. E.; van Aken, P. A.; Koch, C. T.

    2014-01-01

    Holography - originally developed for correcting spherical aberration in transmission electron microscopes - is now used in a wide range of disciplines that involve the propagation of waves, including light optics, electron microscopy, acoustics and seismology. In electron microscopy, the two primary modes of holography are Gabor's original in-line setup and an off-axis approach that was developed subsequently. These two techniques are highly complementary, offering superior phase sensitivity at high and low spatial resolution, respectively. All previous investigations have focused on improving each method individually. Here, we show how the two approaches can be combined in a synergetic fashion to provide phase information with excellent sensitivity across all spatial frequencies, low noise and an efficient use of electron dose. The principle is also expected to be widely to applications of holography in light optics, X-ray optics, acoustics, ultra-sound, terahertz imaging, etc. PMID:25387480

  14. Hybridization approach to in-line and off-axis (electron) holography for superior resolution and phase sensitivity

    NASA Astrophysics Data System (ADS)

    Ozsoy-Keskinbora, C.; Boothroyd, C. B.; Dunin-Borkowski, R. E.; van Aken, P. A.; Koch, C. T.

    2014-11-01

    Holography - originally developed for correcting spherical aberration in transmission electron microscopes - is now used in a wide range of disciplines that involve the propagation of waves, including light optics, electron microscopy, acoustics and seismology. In electron microscopy, the two primary modes of holography are Gabor's original in-line setup and an off-axis approach that was developed subsequently. These two techniques are highly complementary, offering superior phase sensitivity at high and low spatial resolution, respectively. All previous investigations have focused on improving each method individually. Here, we show how the two approaches can be combined in a synergetic fashion to provide phase information with excellent sensitivity across all spatial frequencies, low noise and an efficient use of electron dose. The principle is also expected to be widely to applications of holography in light optics, X-ray optics, acoustics, ultra-sound, terahertz imaging, etc.

  15. Time dependent holography

    NASA Astrophysics Data System (ADS)

    Das, Diptarka

    One of the most important results emerging from string theory is the gauge gravity duality (AdS/CFT correspondence) which tells us that certain problems in particular gravitational backgrounds can be exactly mapped to a particular dual gauge theory a quantum theory very similar to the one explaining the interactions between fundamental subatomic particles. The chief merit of the duality is that a difficult problem in one theory can be mapped to a simpler and solvable problem in the other theory. The duality can be used both ways. Most of the current theoretical framework is suited to study equilibrium systems, or systems where time dependence is at most adiabatic. However in the real world, systems are almost always out of equilibrium. Generically these scenarios are described by quenches, where a parameter of the theory is made time dependent. In this dissertation I describe some of the work done in the context of studying quantum quench using the AdS/CFT correspondence. We recover certain universal scaling type of behavior as the quenching is done through a quantum critical point. Another question that has been explored in the dissertation is time dependence of the gravity theory. Present cosmological observations indicate that our universe is accelerating and is described by a spacetime called de-Sitter(dS). In 2011 there had been a speculation over a possible duality between de-Sitter gravity and a particular field theory (Euclidean SP(N) CFT). However a concrete realization of this proposition was still lacking. Here we explicitly derive the dS/CFT duality using well known methods in field theory. We discovered that the time dimension emerges naturally in the derivation. We also describe further applications and extensions of dS/CFT. KEYWORDS: Holography, AdS/CFT correspondence, Quantum Quench, dS/CFT correspondence, Chaos.

  16. Rainbow holography and its applications

    NASA Astrophysics Data System (ADS)

    Vlasov, N. G.; Ivanov, Vladimir S.

    1993-09-01

    The general equations of the rainbow holography are deduced. Their analysis makes it possible to offer different methods of the rainbow holographic images production. A new way of using the rainbow holograms as optical elements for effective color illuminating of transparent, specular, and polished objects is proposed. Application fields are the advertising industry, shop windows design, etc.

  17. Application of Compressive Sensing to Digital Holography

    DTIC Science & Technology

    2015-05-01

    AFRL-RY-WP-TR-2015-0071 APPLICATION OF COMPRESSIVE SENSING TO DIGITAL HOLOGRAPHY Mark Neifeld University of Arizona...From - To) May 2015 Final 3 September 2013 – 27 February 2015 4. TITLE AND SUBTITLE APPLICATION OF COMPRESSIVE SENSING TO DIGITAL HOLOGRAPHY 5a...from under- sampled data. This work presents a new reconstruction algorithm for use with under-sampled digital holography measurements and yields

  18. Digital holography and 3-D imaging.

    PubMed

    Banerjee, Partha; Barbastathis, George; Kim, Myung; Kukhtarev, Nickolai

    2011-03-01

    This feature issue on Digital Holography and 3-D Imaging comprises 15 papers on digital holographic techniques and applications, computer-generated holography and encryption techniques, and 3-D display. It is hoped that future work in the area leads to innovative applications of digital holography and 3-D imaging to biology and sensing, and to the development of novel nonlinear dynamic digital holographic techniques.

  19. Acoustic Source Localization in Aircraft Interiors Using Microphone Array Technologies

    NASA Technical Reports Server (NTRS)

    Sklanka, Bernard J.; Tuss, Joel R.; Buehrle, Ralph D.; Klos, Jacob; Williams, Earl G.; Valdivia, Nicolas

    2006-01-01

    Using three microphone array configurations at two aircraft body stations on a Boeing 777-300ER flight test, the acoustic radiation characteristics of the sidewall and outboard floor system are investigated by experimental measurement. Analysis of the experimental data is performed using sound intensity calculations for closely spaced microphones, PATCH Inverse Boundary Element Nearfield Acoustic Holography, and Spherical Nearfield Acoustic Holography. Each method is compared assessing strengths and weaknesses, evaluating source identification capability for both broadband and narrowband sources, evaluating sources during transient and steady-state conditions, and quantifying field reconstruction continuity using multiple array positions.

  20. Ultrasonic Imaging of Subsurface Objects Using Photorefractive Dynamic Holography

    SciTech Connect

    Deason, Vance Albert; Telschow, Kenneth Louis; Watson, Scott Marshall

    2001-07-01

    The INEEL has developed a photorefractive ultrasonic imaging technology that records both phase and amplitude of ultrasonic waves on the surface of solids. Phase locked dynamic holography provides full field images of these waves scattered from subsurface defects in solids, and these data are compared with theoretical predictions. Laser light reflected by a vibrating surface is imaged into a photorefractive material where it is mixed in a heterodyne technique with a reference wave. This demodulates the data and provides an image of the ultrasonic waves in either 2 wave or 4 wave mixing mode. These data images are recorded at video frame rates and show phase locked traveling or resonant acoustic waves. This technique can be used over a broad range of ultrasonic frequencies. Acoustic frequencies from 2 kHz to 10 MHz have been imaged, and a point measuring (non-imaging) version of the system has measured picometer amplitudes at 1 GHz.

  1. Aspects of holography

    NASA Astrophysics Data System (ADS)

    Kaplan, Jared Daniel

    The principle of holography---that theories of gravity should be described in terms of their boundaries---has been the driving force behind many great strides in quantum gravity, gauge theory, and even in phenomenology. The most concrete example of holographic duality is the AdS/CFT correspondence, which relates quantum gravity in Anti-deSitter space to a Conformal Field Theory in Minkowski space. In this thesis we begin with a chapter on black holes in the AdS/CFT duality, and then move on to the main line of development, where we describe the exciting first steps towards the discovery of a holographic duality for quantum gravity in flat spacetime. A holographic description of flat spacetime would be a theory of the Scattering Matrix, which contains the quantum mechanical amplitudes that determine how incoming states from past infinity scatter into outgoing states at future infinity. We suspect that a holographic duality between a local spacetime description of quantum gravity and a non-local boundary description of the S-Matrix would be a weak coupling-weak coupling duality. We work towards this concrete goal from the bottom up by studying new methods for computing scattering amplitudes. We begin by studying the BCFW Recursion Relations, which are an explicitly non-local, boundary oriented method for computing tree-level scattering amplitudes. We give an elementary derivation of these relations for general theories in any number of dimensions, showing that their existence is a deep feature of field theory. Next we argue that, counter to naive expectations, N = 8 Supergravity may be the simplest quantum field theory. We demonstrate this by explicitly solving its one-loop S-Matrix with techniques that rely on our understanding of tree amplitudes to vastly simplify calculations. Finally, we show that the BCFW recursion relations find their natural home in Twistor Space, where it is possible to formulate classical scattering theory in a beautiful and manifestly

  2. Digital Holography Display (2)

    NASA Astrophysics Data System (ADS)

    Lee, Cheok Peng; Asundi, A.; Yu, Yang; Xiao, Zhen Zhong

    This paper describes the extension work from the last Digital Holography Projector System. From the developed works shows that, some unforeseen factors have created the difficulties for the system alignment. Such factors are the DMD frame rate, light source and diffractive zero order. It is really the challenging development works to achieve the virtual 3D model display on the high speed rotation screen. The three most key factors are emphasizing: 1) The display device's frame rate; 2) The light source orientation angle; and 3) The zero order filtering optic. 1) This device's is the digital micro mirror, in short is DMD. It is the high speed switching device has developed by the most recent technology. The switching frame rate can go up as high as 291fps. At first, the 8 bits depth file must be digitalized and stored for DMD onboard Ram. The digitalized data are transmitting from the PC USB to DMD onboard Ram. Instead of the data are downloading directly from the PC to DVI or VGA during display, this downloading method cause slower down the display speed, which is the common frame rate of 30 Hz. Next, the onboard Ram data then transfer to the DMD mirror's for display, at the 8 bits 291 fps speed. At this frame rate, the display 2D image can almost cover for 10 of out of the 360 0 in 1 revolution. 2) This laser light source must be installed such that free for orientated in any arbitrary angle from 220 to 450. Which is normalized to the DMD mirrors and the brief sketch show on figure (a). The purpose of orientated the light source is ensure that multi diffractive order would be reflected straight from the mirrors. (This multi diffractive order is the phenomenon of the digital micro mirror's characteristic). This mean, the reconstruct images would be followed the DMD normalized direction reflected up to fibre conduit. Moreover, this orientated method install of the laser light source is making space for other optical lenses or device driver/controller. Because, all

  3. 'Micromanaging de Sitter holography'

    SciTech Connect

    Dong, Xi; Horn, Bart; Silverstein, Eva; Torroba, Gonzalo; /SLAC /Stanford U., Phys. Dept. /Santa Barbara, KITP

    2010-08-26

    We develop tools to engineer de Sitter vacua with semi-holographic duals, using elliptic fibrations and orientifolds to uplift Freund-Rubin compactifications with CFT duals. The dual brane construction is compact and constitutes a microscopic realization of the dS/dS correspondence, realizing d-dimensional de Sitter space as a warped compactification down to (d-1)-dimensional de Sitter gravity coupled to a pair of large-N matter sectors. This provides a parametric microscopic interpretation of the Gibbons-Hawking entropy. We illustrate these ideas with an explicit class of examples in three dimensions, and describe ongoing work on four-dimensional constructions. The Gibbons-Hawking entropy of the de Sitter horizon [1] invites a microscopic interpretation and a holographic formulation of inflating spacetimes. Much progress was made in the analogous problem in black hole physics using special black holes in string theory whose microstates could be reliably counted, such as those analyzed in [2,3]; this led to the AdS/CFT correspondence [4]. In contrast, a microscopic understanding of the entropy of de Sitter space is more difficult for several reasons including its potential dynamical connections to other backgrounds (metastability), the absence of a non-fluctuating timelike boundary, and the absence of supersymmetry. In this paper, we develop a class of de Sitter constructions in string theory, built up from AdS/CFT dual pairs along the lines of [5], which are simple enough to provide a microscopic accounting of the parametric scaling of the Gibbons-Hawking entropy. These models realize microscopically a semi-holographic description of metastable de Sitter space which had been derived macroscopically in [6]. It would also be interesting to connect this to other approaches to de Sitter holography such as [7, 8] and to other manifestations of the de Sitter entropy such as [9]. The construction is somewhat analogous to neutral black branes analyzed in [11]. We will

  4. Surpassing digital holography limits by lensless object scanning holography.

    PubMed

    Micó, Vicente; Ferreira, Carlos; García, Javier

    2012-04-23

    We present lensless object scanning holography (LOSH) as a fully lensless method, capable of improving image quality in reflective digital Fourier holography, by means of an extremely simplified experimental setup. LOSH is based on the recording and digital post-processing of a set of digital lensless holograms and results in a synthetic image with improved resolution, field of view (FOV), signal-to-noise ratio (SNR), and depth of field (DOF). The superresolution (SR) effect arises from the generation of a synthetic aperture (SA) based on the linear movement of the inspected object. The same scanning principle enlarges the object FOV. SNR enhancement is achieved by speckle suppression and coherent artifacts averaging due to the coherent addition of the multiple partially overlapping bandpass images. And DOF extension is performed by digital refocusing to different object's sections. Experimental results showing an impressive image quality improvement are reported for a one-dimensional reflective resolution test target.

  5. Multicolor Holography With Phase Shifting

    NASA Technical Reports Server (NTRS)

    Vikram, Chandra S.

    1996-01-01

    Prototype apparatus constructed to test feasibility of two-color holographic interferometric scheme in which data for reconstructing holographic wavefront obtained with help of phase-shifting technique. Provides two sets of data needed to solve equations for effects of temperature and concentration. Concept extended to holography at three or more wavelengths to measure three or more phenomena associated with significant variations in index of refraction

  6. Phase-shift coherence holography.

    PubMed

    Naik, Dinesh N; Ezawa, Takahiro; Miyamoto, Yoko; Takeda, Mitsuo

    2010-05-15

    We propose and experimentally demonstrate a new reconstruction scheme for coherence holography using computer-generated phase-shift coherence holograms. A 3D object encoded into the spatial coherence function is reconstructed directly from a set of incoherently illuminated computer-generated holograms with numerically introduced phase shifts. Although a rotating ground glass is used to introduce spatially incoherent illumination, the phase-shifting portion of the system is simple and free from mechanically moving components.

  7. Multicolor holography: a comparative study

    NASA Astrophysics Data System (ADS)

    Oliveira, Rosa M.; Bernardo, Luis M.; Pinto, Joao L.

    2000-10-01

    A multicolor holography study case will be presented with emphasis on color control in different silver-halide materials. It has been systematized in order to compare the results obtained with Agfa 8E 75HD to those with Slavich PFG-01. Some experiments were made and the emulsion was manipulated before exposure to achieve high quality multicolored white light reflection holograms. This work has therefore been developed in order to obtain the various colors in a very well controlled way.

  8. Particle and flow field holography

    NASA Astrophysics Data System (ADS)

    Trolinger, J. D.

    1985-01-01

    The current status of particle field and flow field holography is examined, and the methods based on the principles of either class of imagery are described. Special consideration is given to the automated data reduction technology. Current applications of flow diagnostics, which can provide thousands of holograms during a one-day experiment, include NASA applications in wind tunnel holography, in a Laser Doppler Velocimeter, in holographic movies, and in an optical device for recording crystal growth at zero gravity, to be used in the Space Lab 3 shuttle mission scheduled for May 1985. Military applications of the flow diagnostics include the use of holographic tomography for visualizing flow fields around airborne structures, in wind tunnels, and in the analyses of rocket exhausts and gun ranges. The information provided by the particle sizing holography, concerning the size, shape, number, and velocity of particles and the records of the particle break-up phenomenon, can be used in various military field oriented and airborne applications and in meteorology and environment protection science.

  9. Holography: childrens' window to relativity

    NASA Astrophysics Data System (ADS)

    MacShane, James E.

    1995-02-01

    This paper is concerned with the development of the concept of natural education. Psychology has discovered that all humans learn intuitively the cultural concepts of time from birth to eight and one-half to ten years of age. Einstein showed us that this must also be the natural time for the development of spatial concepts. The importance of this has been dramatized for me in the past eight years that I have been developing the Laser Arts and Holography Programs and Workshops. I have worked with over 100,000 students kindergarten through eighth grade. I have worked with 175 students age 8 to 10 in three hour and one half workshops specifically on the development of time and space concepts. The concepts developed are based upon the vast amount of psychological evidence related to the natural development of time and space understandings, Dr. Nils Abramson's 'Light in Flight' and subsequent work on the clarification of relativity through holography, and Maria Montessori's method of Scientific Education. The paper also demonstrates the natural method of teaching science to younger students is to teach scientifically. All of the research which has been done in the past 100 years has been used by the educational institutions to try to improve the system. What has not been done is changing the system to how humans learn. Because of the perceived hi-tech nature of the program I am able to dramatize the potential. An outline for a holography curriculum kindergarten through eighth grade is included.

  10. Acoustic-optical imaging without immersion

    NASA Technical Reports Server (NTRS)

    Liu, H.

    1979-01-01

    System using membraneous end wall of Bragg cell to separate test specimen from acoustic transmission medium, operates in real time and uses readily available optical components. System can be easily set up and maintained by people with little or no training in holography.

  11. Identification of nah-1 genes of the Pseudomonas putida naphthalene-degrading NPL-41 plasmid operon.

    PubMed

    Serebriiskaya, T S; Lenets, A A; Goldenkova, I V; Kobets, N S; Piruzian, E S

    1999-01-01

    Pseudomonas putida BS202 degrades naphthalene via a plasmid-encoded catabolic pathway. The nucleotide sequence of the nahC gene encoding one of this pathway enzymes, 1,2-dihydroxynaphthalene dioxygenase, has been determined. Analysis of nucleotide sequence of its flanking regions identified partially the nahF and putative nahQ genes. Comparison of these three genes with corresponding ones in the NAH7 plasmid and DOX operon showed a high degree of homology.

  12. Underwater holography: past and future

    NASA Astrophysics Data System (ADS)

    Watson, John

    2006-05-01

    Holography is a well-known optical technique which can provide valuable information on the location and distribution of small particles in three-dimensional space. For several years now, we have utilised holography for high-precision subsea inspection and measurement. One specific application which spurred much of our work was the need for high-precision inspection and analysis of plankton sizes, distribution and species identification. To this end we have developed a subsea holographic camera (HoloMar) for recording of plankton and other marine organisms in situ in their natural environment. This camera is unique in that it is able to record simultaneous in-line and off-axis holograms to cover a range of size of marine organisms from a few microns to tens of millimetres and at concentrations from a few particles per cubic centimetre to dense aggregates. Holograms of aquatic systems of up to 50000 cm 3 volume (off-axis) and 9500 cm 3 (in-line), have been recorded in situ, using a pulsed laser (Q-switched, frequency-doubled Nd-YAG, 532 nm). The use of a pulsed laser effectively "freezes" the scene at a given instant. Although the recording of the holograms takes place in water, replay of the image is carried out in the laboratory in air, using the projected (real) image mode of reconstruction. By precision translation of a computer-controlled video-camera through the replayed image volume and performing "optical sectioning" on the image, individual organisms can be isolated and their size, shape and relative location precisely determined. Image processing algorithms, will allow optimisation of the holographic image together with automated identification of individual species and enumeration of concentrations. The local interactions between different organisms and particles can be observed, recorded and quantitatively determined. Following initial laboratory and observation tank testing, the holo-camera was deployed in a sea loch in the West of Scotland to a depth of

  13. Aesthetics and representation in holography

    NASA Astrophysics Data System (ADS)

    Kac, Eduardo

    1995-02-01

    Every medium has a code, a set of rules or conventions according to which determined elements are organized into a signifying system. The English language is a code as is perspective in painting and photography. In the first case, the elements are phonemes organized into words and sentences according to a social convention: the syntax of English. In the second case, the elements are dots and lines organized into pictures according to a geometric method. An artist or movement can break the conventions of the medium, as has done Cezanne with painting, Moholy-Nagy with photography and cummings with the English idiom in poetry, and create new elements and rules for combining them. If this is done, the level of predictability (or conventionality) is lowered and unpredictability is increased -- becoming more difficult for the immediate audience to understand it. But once these new rules are learned and the ideas behind them widely understood, the level of unpredictability is lowered and they become new conventions that can be accepted by the audience. Holographic artists exploring the medium -- as opposed to advertisers using holography, who favor a high level of predictability -- are breaking several visual and cultural conventions. As a matter of fact, holography is so new that many questions are left open about the nature of the medium. Therefore, any attempt to clarify the issues raised by holography on a cultural level has a prospective (and not conclusive) tone, concentrating more thoroughly on general points and on the promise of its potentialities than on the records of its historical achievements so far.

  14. Frequency analysis of digital holography

    NASA Astrophysics Data System (ADS)

    Kreis, Thomas M.

    2002-04-01

    A coherent optical imaging system consisting of recording a digital hologram by a CCD array and numerical reconstruction of the complex wave field in a computer is subjected to a frequency analysis. This analysis recognizes Fresnel and lensless Fourier transform holography; collimated and divergent reference waves; as well as the real image, the virtual image, and the dc term. The influences of finite sampling and the fill factor of the CCD pixels are examined. The impulse response of the system is a shifted Fraunhofer diffraction pattern of the aperture defined by the CCD. A fill factor below unity leads to a contrast decrease, which is quantitatively described in the modulation transfer function.

  15. Digital holography based submicron thermometry.

    PubMed

    Moradi, Amin; Akhlaghi, Ehsan A; Hajizedeh, Faegheh; Reihani, S Nader S

    2016-12-12

    Here we introduce a phase-shifting digital holography-based method to determine the temperature profile around an irradiated (sub-)micron spherical bead. The method utilizes a Mach-Zehnder interferometer implemented into an open setup microscope. The results of irradiated gold spheres with diameter of 400 nm and also silver-coated micron-sized silica beads embedded in silicone oil are presented. We show that the applied method is able to accurately determine the surface temperature with accuracy of 1 °C. Our experimental results perfectly confirm the theoretical prediction of temperature profile around the irradiated bead.

  16. Damage Detection Using Holography and Interferometry

    NASA Technical Reports Server (NTRS)

    Decker, Arthur J.

    2003-01-01

    This paper reviews classical approaches to damage detection using laser holography and interferometry. The paper then details the modern uses of electronic holography and neural-net-processed characteristic patterns to detect structural damage. The design of the neural networks and the preparation of the training sets are discussed. The use of a technique to optimize the training sets, called folding, is explained. Then a training procedure is detailed that uses the holography-measured vibration modes of the undamaged structures to impart damage-detection sensitivity to the neural networks. The inspections of an optical strain gauge mounting plate and an International Space Station cold plate are presented as examples.

  17. Holograms for acoustics

    NASA Astrophysics Data System (ADS)

    Melde, Kai; Mark, Andrew G.; Qiu, Tian; Fischer, Peer

    2016-09-01

    Holographic techniques are fundamental to applications such as volumetric displays, high-density data storage and optical tweezers that require spatial control of intricate optical or acoustic fields within a three-dimensional volume. The basis of holography is spatial storage of the phase and/or amplitude profile of the desired wavefront in a manner that allows that wavefront to be reconstructed by interference when the hologram is illuminated with a suitable coherent source. Modern computer-generated holography skips the process of recording a hologram from a physical scene, and instead calculates the required phase profile before rendering it for reconstruction. In ultrasound applications, the phase profile is typically generated by discrete and independently driven ultrasound sources; however, these can only be used in small numbers, which limits the complexity or degrees of freedom that can be attained in the wavefront. Here we introduce monolithic acoustic holograms, which can reconstruct diffraction-limited acoustic pressure fields and thus arbitrary ultrasound beams. We use rapid fabrication to craft the holograms and achieve reconstruction degrees of freedom two orders of magnitude higher than commercial phased array sources. The technique is inexpensive, appropriate for both transmission and reflection elements, and scales well to higher information content, larger aperture size and higher power. The complex three-dimensional pressure and phase distributions produced by these acoustic holograms allow us to demonstrate new approaches to controlled ultrasonic manipulation of solids in water, and of liquids and solids in air. We expect that acoustic holograms will enable new capabilities in beam-steering and the contactless transfer of power, improve medical imaging, and drive new applications of ultrasound.

  18. Resolution factors in edgeline holography.

    PubMed

    Trolinger, J D; Gee, T H

    1971-06-01

    When an in-line Fresnel hologram of an object such as a projectile in flight is made, the reconstruction comprises an image of the outside edge of the object superimposed upon a Fresnel diffraction pattern of the edge and an unmodulated portion of the reconstruction beam. When the reconstructed image is bandpass filtered, the only remaining significant contribution is that of a diffraction pattern which is symmetrical about an edgeline gaussian image of the object. The present paper discusses the application of this type of holography in accurately locating the edge of a large dynamic object, the position of which is not accurately known in any dimension. A theoretical and experimental analysis was performed to study the effects of motion, hologram size, film type, and practical limitations upon the attainable resolution in the reconstructed image. The bandlimiting effect of motion is used to relate the motion effected resolution limit of holography to that of photography. The study shows that an edgeline can be accurately located even at high velocity normal to the edge.

  19. Dissociation energy of the ground state of NaH

    NASA Astrophysics Data System (ADS)

    Huang, Hsien-Yu; Lu, Tsai-Lien; Whang, Thou-Jen; Chang, Yung-Yung; Tsai, Chin-Chun

    2010-07-01

    The dissociation energy of the ground state of NaH was determined by analyzing the observed near dissociation rovibrational levels. These levels were reached by stimulated emission pumping and fluorescence depletion spectroscopy. A total of 114 rovibrational levels in the ranges 9≤v″≤21 and 1≤J″≤14 were assigned to the X Σ1+ state of NaH. The highest vibrational level observed was only about 40 cm-1 from the dissociation limit in the ground state. One quasibound state, above the dissociation limit and confined by the centrifugal barrier, was observed. Determining the vibrational quantum number at dissociation vD from the highest four vibrational levels yielded the dissociation energy De=15 815±5 cm-1. Based on new observations and available data, a set of Dunham coefficients and the rotationless Rydberg-Klein-Rees curve were constructed. The effective potential curve and the quasibound states were discussed.

  20. Present State Iof Holography In Japan

    NASA Astrophysics Data System (ADS)

    Suzuki, Masane; Hayashi, Yuzo; Yamamoto, Y.

    1983-07-01

    In 1948,Dr. Dennis Gabor introduced the theory of holography as "the optical recording of the object wave formed by the resulting interference pattern of two mutually coherent, component light beams." Through the studies of enumerous practical applications, the theory of holography was further advanced to be used in conjunction with the laser beam to better serve a more practical minded industry. Such developments were introduced and engineered by Dr. Emmett Leith and Dr. Juris Upatnieks in 1962.

  1. Horizontal-parallax-only electronic holography

    NASA Astrophysics Data System (ADS)

    Poon, T.-C.; Akin, T.; Indebetouw, G.; Kim, T.

    2005-04-01

    The principle of optical scanning holography (OSH) is proposed to acquire horizontal-parallax-only (HPO) holographic information electronically. We first briefly summarize the results of OSH and then discuss how HPO-electronic holographic information can be acquired using OSH. Finally we provide simulations to illustrate and clarify the proposed idea. Although many ideas of HPO-holography have been proposed and studied, to the best of our knowledge, this is the first proposed electronic technique to acquire HPO-holographic information.

  2. Applications of real-time holography

    NASA Astrophysics Data System (ADS)

    Feinberg, J.

    1985-01-01

    Holographic principles are discussed, with a description of the steps of hologram production and reconstruction and the materials used in storage of the images. Real-time holography applications, including photolithography, double-exposure interferometry, time-averaged holography, parallel optical processing, optical phase conjugation, beam steering, and moving holograms, are described in detail. In addition, current areas of active research and some experimental applications are discussed.

  3. Helioseismic Holography and a Study of the Process of Magnetic Flux Disappearance in Canceling Bipoles

    NASA Technical Reports Server (NTRS)

    Lindsey, Charles; Harvey, Karen L.; Braun, D.; Jones, H. P.; Penn, M.; Hassler, D.

    2001-01-01

    Project 1: We have developed and applied a technique of helioseismic holography along the lines of originally set out in our proposal. The result of the application of this diagnostic technique to solar activity and the quiet Sun has produced a number of important discoveries: (1) acoustic moats surrounding sunspots; (2) acoustic glories surround large active regions; (3) acoustic condensations beneath active regions; and (4) temporally-resolve acoustic images of a solar flare. These results have been published in a series of papers in the Astrophysical Journal. We think that helioseismic holography is now established as the most powerful and discriminating diagnostic in local helioseismology. Project 2: We conducted a collaborative observational program to define the physical character and magnetic geometry of canceling magnetic bipoles aimed at determining if the cancellation process is the result of submergence of magnetic fields. This assessment is based on ground-based observations combining photospheric and chromospheric magnetograms from NSO/KP, BBSO, and SOHO-MDI, and EUV and X-ray images from SOHO EIT/CDS, Yohkoh/SXT, and TRACE. Our study involves the analysis of data taken during three observing campaigns to define the height structure of canceling bipoles inferred from magnetic field and intensity images, and how this varies with time. We find that some canceling bipoles can be explained by the submerge of their magnetic flux. A paper on the results of this analysis will be presented at an upcoming scientific meeting and be written up for publication.

  4. Visualizing Breath using Digital Holography

    NASA Astrophysics Data System (ADS)

    Hobson, P. R.; Reid, I. D.; Wilton, J. B.

    2013-02-01

    Artist Jayne Wilton and physicists Peter Hobson and Ivan Reid of Brunel University are collaborating at Brunel University on a project which aims to use a range of techniques to make visible the normally invisible dynamics of the breath and the verbal and non-verbal communication it facilitates. The breath is a source of a wide range of chemical, auditory and physical exchanges with the direct environment. Digital Holography is being investigated to enable a visually stimulating articulation of the physical trajectory of the breath as it leaves the mouth. Initial findings of this research are presented. Real time digital hologram replay allows the audience to move through holographs of breath-born particles.

  5. Digital holography-based steganography.

    PubMed

    Hamam, Habib

    2010-12-15

    A steganographic method offering a high hiding capacity is presented in which the techniques of digital holography are used to distribute information from a small secret image across the larger pixel field of a cover image. An iterative algorithm is used to design a phase-only or complex hologram from a padded version of the secret image, quantizing this data according to the carrier data bits that are available within the intended cover image. By introducing the hologram data only into low-order bits of larger amplitude cover pixels, the change in the cover image remains imperceptible to the casual observer, with a peak signal-to-noise ratio of >40 dB.

  6. Digital holography to light field

    NASA Astrophysics Data System (ADS)

    Asundi, Anand; Zuo, Chao

    2014-05-01

    Holography uses wave (physical) optical principles of interference and diffraction to record and display images. Interference allows us to record the amplitude and phase of the optical wave emanating from an object on a film or recording medium and diffraction enables us to see this wave-field, i.e. the amplitude and phase of the object. Visually this corresponds to both perspective and depth information being reconstructed as in the original scene. Digital Holography has enabled quantification of phase which in some applications provides meaningful engineering parameters. There is growing interest in reconstructing this wavefield without interference. Thus the non-interferometric Transport of Intensity Equation (TIE) method is gaining increased research, which uses two or more defocused images to reconstruct the phase. Due to its non-interferometric nature, TIE relaxes the stringent beam-coherence requirements for interferometry, extending its applications to various optical fields with arbitrary spatial and temporal coherence. The alternate school of thought emerges from the computer science community primarily deals with ray optics. In a normal imaging system all rays emerging from an object point into are focused to a conjugate image point. Information of ray direction is lost and thus the perspective and depth information. A light field image is one that has information of both amplitude and direction of rays fanning from any object point and thus provides perspective (or what could be termed as phase) of the object wave as well. It would thus be possible to extract phase as we know it from this albeit for a coherent illumination case.

  7. Frustrated total internal reflection acoustic field sensor

    DOEpatents

    Kallman, Jeffrey S.

    2000-01-01

    A frustrated total internal reflection acoustic field sensor which allows the acquisition of the acoustic field over an entire plane, all at once. The sensor finds use in acoustic holography and acoustic diffraction tomography. For example, the sensor may be produced by a transparent plate with transparent support members tall enough to support one or more flexible membranes at an appropriate height for frustrated total internal reflection to occur. An acoustic wave causes the membrane to deflect away from its quiescent position and thus changes the amount of light that tunnels through the gap formed by the support members and into the membrane, and so changes the amount of light reflected by the membrane. The sensor(s) is illuminated by a uniform tight field, and the reflection from the sensor yields acoustic wave amplitude and phase information which can be picked up electronically or otherwise.

  8. Recent developments on holography in China

    NASA Astrophysics Data System (ADS)

    Hsu, Dahsiung; Jiao, Jiangzhong; Tao, Huiying; Long, Pin

    1991-02-01

    Since the 1985 Lake Forest International Conference on display holography, USA) more developments have been made on holographic applications in China among which the important events and progress were: the International Conference on holography applications em bossing holography new holographic optical elements and equipments etc. . 1. INTERNATIONAL CONFEPENCE ON GRAPHY APPLICATIONS'' ( I CHA ''86. BEIJING) More than 280 holographers from 18 countries gathered in the Science Hall in Beijing from July 2 to for the International Conference on holography applications''86. The conference was sponsor ed by the Chinese OPtical Society the Chinese Theoretical Applied Mechanics Society and cosponsored by the Society of Photooptical Instrumentation Engineers the European Photonic Association in cooperation with the China Association for Science And Technology. It was chaired by Prof. Wang Daheng vice president of the China Association for Science Technology and president of the Chinese Optical Society cochaired by DP. H. J. Caulfield of the Univ. of Alabama Dr. G. von Bally of the Munster Univ. in West Germany and Dr. J. Tsujiuchi of the Tokyo Institute of Technology. SPIE Vol. 1238 Three-Dimensional Holography: Science Culture Education (1989) / 13

  9. Wavelet image processing applied to optical and digital holography: past achievements and future challenges

    NASA Astrophysics Data System (ADS)

    Jones, Katharine J.

    2005-08-01

    The link between wavelets and optics goes back to the work of Dennis Gabor who both invented holography and developed Gabor decompositions. Holography involves 3-D images. Gabor decompositions involves 1-D signals. Gabor decompositions are the predecessors of wavelets. Wavelet image processing of holography, both optical holography and digital holography, will be examined with respect to past achievements and future challenges.

  10. Holography in the curriculum of medical institutes

    NASA Astrophysics Data System (ADS)

    Gorelik, S. Y.; Nagibina, I. M.; Baranov, S. V.; Bolshakov, Oleg P.; Petrishin, V. L.

    1995-11-01

    Holography at present is the most effective technique of obtaining 3-D images of different objects. That's why there is more and more dissemination of holography in different fields of science and engineering, for example, in medicine. So, last time the technique of synthesized holograms obtained for evaluating inner organs states of patients without surgical intervention was designed. Due to properties of the hologram such as high quality of image and relative simplicity of duplication it is clear that holography could take its place in the curriculum of medical specializations because posters, photos, and models cannot give a full notation about an object of interest. The attempt to obtain holographical complete sets to demonstrate the most frequent pathologic changes of a human's bones was undertaken by our Institutes. The aim of our research was to obtain holograms with the following properties: minimum cost and high quality of reconstructed image to identify both the presented objects and the pathologic changes of them.

  11. Advanced technology development multi-color holography

    NASA Technical Reports Server (NTRS)

    Vikram, Chandra S.

    1994-01-01

    Several key aspects of multi-color holography and some non-conventional ways to study the holographic reconstructions are considered. The error analysis of three-color holography is considered in detail with particular example of a typical triglycine sulfate crystal growth situation. For the numerical analysis of the fringe patterns, a new algorithm is introduced with experimental verification using sugar-water solution. The role of the phase difference among component holograms is also critically considered with examples of several two- and three-color situations. The status of experimentation on two-color holography and fabrication of a small breadboard system is also reported. Finally, some successful demonstrations of unconventional ways to study holographic reconstructions are described. These methods are deflectometry and confocal optical processing using some Spacelab III holograms.

  12. Spin and wavelength multiplexed nonlinear metasurface holography

    PubMed Central

    Ye, Weimin; Zeuner, Franziska; Li, Xin; Reineke, Bernhard; He, Shan; Qiu, Cheng-Wei; Liu, Juan; Wang, Yongtian; Zhang, Shuang; Zentgraf, Thomas

    2016-01-01

    Metasurfaces, as the ultrathin version of metamaterials, have caught growing attention due to their superior capability in controlling the phase, amplitude and polarization states of light. Among various types of metasurfaces, geometric metasurface that encodes a geometric or Pancharatnam–Berry phase into the orientation angle of the constituent meta-atoms has shown great potential in controlling light in both linear and nonlinear optical regimes. The robust and dispersionless nature of the geometric phase simplifies the wave manipulation tremendously. Benefitting from the continuous phase control, metasurface holography has exhibited advantages over conventional depth controlled holography with discretized phase levels. Here we report on spin and wavelength multiplexed nonlinear metasurface holography, which allows construction of multiple target holographic images carried independently by the fundamental and harmonic generation waves of different spins. The nonlinear holograms provide independent, nondispersive and crosstalk-free post-selective channels for holographic multiplexing and multidimensional optical data storages, anti-counterfeiting, and optical encryption. PMID:27306147

  13. Holography with a Landau pole

    NASA Astrophysics Data System (ADS)

    Faedo, Antón F.; Mateos, David; Pantelidou, Christiana; Tarrío, Javier

    2017-02-01

    Holography for UV-incomplete gauge theories is important but poorly understood. A paradigmatic example is d = 4, N=4 super Yang-Mills coupled to N f quark flavors, which possesses a Landau pole at a UV scale ΛLP. The dual gravity solution exhibits a UV singularity at a finite proper distance along the holographic direction. Despite this, holographic renormalization can be fully implemented via analytic continuation to an AdS solution. The presence of a UV cut-off manifests itself in several interesting ways. At energies E ≪ ΛLP no pathologies appear, as expected from effective field theory. In contrast, at scales E ≲ ΛLP the gravitational potential becomes repulsive, and at temperatures T ≲ ΛLP the specific heat becomes negative. Although we focus on N=4 super Yang-Mills with flavor, our qualitative results apply to a much more general class of theories, since they only depend on the fact that the metric near the UV singularity is a hyper-scaling violating metric with exponent θ > d - 1.

  14. DSS-24 microwave holography measurements

    NASA Technical Reports Server (NTRS)

    Rochblatt, D. J.; Withington, P. M.; Jackson, H. J.

    1995-01-01

    The JPL DSN Microwave Antenna Holography System (MAHST) was applied to the newly constructed DSS-24 34-m beam-waveguide antenna at Goldstone, California. The application of MAHST measurements and corrections at DSS 24 provided the critical RF performance necessary to not only meet the project requirements and goals, but to surpass them. A performance increase of 0.35 dB at X-band (8.45 GHz) and 4.9 dB at Ka-band (32 GHz) was provided by MAHST, resulting in peak efficiencies of 75.25 percent at X-band and 60.6 percent at Ka-band (measured from the Cassegrain focus at f1). The MAHST enabled setting the main reflector panels of DSS 24 to 0.25-mm rms, making DSS 24 the highest precision antenna in the NASA/JPL DSN. The precision of the DSS-24 antenna (diameter/rms) is 1.36 x 10(exp 5), and its gain limit is at 95 GHz.

  15. Acoustic neuroma

    MedlinePlus

    Vestibular schwannoma; Tumor - acoustic; Cerebellopontine angle tumor; Angle tumor; Hearing loss - acoustic; Tinnitus - acoustic ... Acoustic neuromas have been linked with the genetic disorder neurofibromatosis type 2 (NF2). Acoustic neuromas are uncommon.

  16. Holography - Application To Art: Curatorial Observations

    NASA Astrophysics Data System (ADS)

    Dinsmore, Sydney

    1987-06-01

    An exploration of the need to define a specific and critical language to describe the art of holography. Within any discussion of art, critical analysis must maintain an objective openess, particularily when the discourse concerns new media. To apply technological invention to art, new media is often without precedent on which to base criticism and bias. For this reason, holography falls prey to comparative rhetoric and established evaluation of other forms of imaging,as photography emulated the compositional romanticism of painting initially. Isolated and often misunderstood within the context of history, new media vascillates between legitimacy and curiosity in an attempt to create specific parameters to identify perceptual transition.

  17. Systems analysis for DSN microwave antenna holography

    NASA Technical Reports Server (NTRS)

    Rochblatt, D. J.

    1989-01-01

    Proposed systems for Deep Space Network (DSN) microwave antenna holography are analyzed. Microwave holography, as applied to antennas, is a technique which utilizes the Fourier Transform relation between the complex far-field radiation pattern of an antenna and the complex aperture field distribution to provide a methodology for the analysis and evaluation of antenna performance. Resulting aperture phase and amplitude distribution data are used to precisely characterize various crucial performance parameters, including panel alignment, subreflector position, antenna aperture illumination, directivity at various frequencies, and gravity deformation. Microwave holographic analysis provides diagnostic capacity as well as being a powerful tool for evaluating antenna design specifications and their corresponding theoretical models.

  18. Is holography ready for yet another life? or make holography great again

    NASA Astrophysics Data System (ADS)

    Trolinger, James D.

    2016-08-01

    Holographic metrology, unlike most other applications of holography, has always thrived and continues to thrive by continuously incorporating new supporting technologies that make it more powerful and useful. Successes, failures, lives, and deaths are examined and recognized as evolutionary steps that position the field where opportunities are as great and as many as ever. This is a story of that evolution. Comparisons and analogies with other applications of holography such as data storage, archiving, the arts, entertainment, advertising, and security and their evolution are interesting. Critical events, successes, mistakes, and coincidences represent milestones of abandonment or failure to deliver in many holography communities that followed a different evolutionary path. Events and new technical developments continue to emerge in supporting fields that can revive and expand all holography applications. New opportunities are described with encouragement to act on them and take some risks. Don't wait until all of the required technology and hardware are available, because good scientists always act before then. The paper is about "making holography great again" and your opportunity to be a part of the upcoming revolution. Although the discussion focuses on holographic metrology, the same principles should apply to other holography communities.

  19. Cyclic adenosine monophosphate acutely inhibits and chronically stimulates Na/H antiporter in OKP cells.

    PubMed Central

    Cano, A; Preisig, P; Alpern, R J

    1993-01-01

    Parathyroid hormone, dopamine, alpha-adrenergic catecholamines, and angiotensin II regulate renal Na excretion, at least in part through modulation of acute cyclic (c)AMP-induced proximal tubule Na/H antiporter inhibition. The present studies examined the effect of chronic increases in cell cAMP on Na/H antiporter activity in OKP cells. Whereas 8-bromo cAMP acutely inhibited Na/H antiporter activity, chronic application for 6 h led to a 24% increase in Na/H antiporter activity measured 16-20 h after cAMP removal. This chronic persistent activation of the Na/H antiporter required > 2 h exposure. This effect was not a nonspecific effect of 8-bromo cAMP, in that addition of forskolin or forskolin + 3-isobutyl-1-methylxanthine for 6 h also led to a chronic persistent increase in Na/H antiporter activity. Inhibition of protein synthesis with cycloheximide prevented 8-bromo cAMP-induced Na/H antiporter stimulation. Although 8-bromo cAMP addition decreased cell pH by 0.15-0.20 pH U, Na/H antiporter stimulation could be dissociated from cell acidification. In summary, while cAMP acutely inhibits Na/H antiporter activity, it chronically increases antiporter activity. This chronic activation occurs with exogenous addition or endogenous generation of cAMP. These results imply that for hormones that modulate renal Na excretion and proximal tubule Na/H antiporter activity via cAMP and protein kinase A, acute effects may not predict chronic effects. PMID:7691881

  20. Adaptive phase calibration of a microphone array for acoustic holography.

    PubMed

    Teal, Paul D; Poletti, Mark A

    2010-04-01

    Previous work has indicated that a limitation on the performance of a circular microphone array for holographic sound field recording at low frequencies is phase mismatch between the microphones in the array. At low frequencies these variations become more significant than at mid-range and high frequencies because the high order phase mode responses at low frequencies are lower in amplitude. This paper demonstrates the feasibility of a "self-calibration" method. The basis of the calibration is to estimate the location of one or more wide-band sources using mid-range frequencies and to use this source location information to perform correction to the array at low frequencies. In its simplest form the calibration must be performed in an anechoic environment, since multipath effects at widely differing frequencies are uncorrelated. The approach is first demonstrated in such an environment using recordings from an array of high quality microphones. The technique is then extended to an adaptive calibration that can be used in an environment that is somewhat reverberant. The validity of the adaptive approach is demonstrated using recordings from an array of inexpensive microphones.

  1. Synthetic optical holography for rapid nanoimaging

    PubMed Central

    Schnell, M.; Carney, P. S.; Hillenbrand, R.

    2014-01-01

    Holography has paved the way for phase imaging in a variety of wide-field techniques, including electron, X-ray and optical microscopy. In scanning optical microscopy, however, the serial fashion of image acquisition seems to challenge a direct implementation of traditional holography. Here we introduce synthetic optical holography (SOH) for quantitative phase-resolved imaging in scanning optical microscopy. It uniquely combines fast phase imaging, technical simplicity and simultaneous operation at visible and infrared frequencies with a single reference arm. We demonstrate SOH with a scattering-type scanning near-field optical microscope (s-SNOM) where it enables reliable quantitative phase-resolved near-field imaging with unprecedented speed. We apply these capabilities to nanoscale, non-invasive and rapid screening of grain boundaries in CVD-grown graphene, by recording 65 kilopixel near-field images in 26 s and 2.3 megapixel images in 13 min. Beyond s-SNOM, the SOH concept could boost the implementation of holography in other scanning imaging applications such as confocal microscopy. PMID:24651276

  2. Haptic Holography/Touching the Ethereal

    NASA Astrophysics Data System (ADS)

    Page, Michael

    2013-02-01

    Haptic Holography, was perhaps, first proposed by workers at MIT in the 90s. The Media Lab, headed up by Dr. Stephen Benton, with published papers by Wendy Plesiak and Ravi Pappuh. -1 Recent developments in both the technology of digital holography and haptics have made it practical to conduct further investigations. Haptic holography is auto-stereoscopic and provides co-axial viewing for the user. Haptic holography may find application in medical & surgical training and as a new form of synthetic reality for artists and designers. At OCAD's PHASE Lab (Prototypes for Holographic Art and Science Explorations) workers are exploring hybrid forms of augmented reality, that combine haptics, interactivity and auto-stereoscopic imagery. Conventional Haptic environments, while presenting a 3D physics environment, typically provide a 2D visual work/play space. Orienteering in such an environment creates an uncertain spatial relationship for the user. Our group creates 3d models from which we create holographic constructs. The same model is used to create the physics environment. The two models are super-imposed. The result: Holograms you can touch.

  3. Advanced technology development multi-color holography

    NASA Technical Reports Server (NTRS)

    Vikram, Chandra S.

    1993-01-01

    This is the final report of the Multi-color Holography project. The comprehensive study considers some strategic aspects of multi-color holography. First, various methods of available techniques for accurate fringe counting are reviewed. These are heterodyne interferometry, quasi-heterodyne interferometry, and phase-shifting interferometry. Phase-shifting interferometry was found to be the most suitable for multi-color holography. Details of experimentation with a sugar solution are also reported where better than 1/200 of a fringe order measurement capability was established. Rotating plate glass phase shifter was used for the experimentation. The report then describes the possible role of using more than two wavelengths with special reference-to-object beam intensity ratio needs in multicolor holography. Some specific two- and three-color cases are also described in detail. Then some new analysis methods of the reconstructed wavefront are considered. These are deflectometry, speckle metrology, confocal optical signal processing, and phase shifting technique related applications. Finally, design aspects of an experimental breadboard are presented.

  4. Entangled States, Holography and Quantum Surfaces

    SciTech Connect

    Chapline, G F

    2003-08-13

    Starting with an elementary discussion of quantum holography, we show that entangled quantum states of qubits provide a ''local'' representation of the global geometry and topology of quantum Riemann surfaces. This representation may play an important role in both mathematics and physics. Indeed, the simplest way to represent the fundamental objects in a ''theory of everything'' may be as muti-qubit entangled states.

  5. "Hare and Hounds" Tests of Helioseismic Holography

    NASA Astrophysics Data System (ADS)

    Birch, A. C.; Parchevsky, K. V.; Braun, D. C.; Kosovichev, A. G.

    2011-08-01

    We use the output of numerical wave-propagation simulations as synthetic data for "hare and hounds" tests of helioseismic holography. In the simple non-magnetic models examined here, we show that when the inversion method includes a consistent treatment of the filtering applied during the data analysis the inversions for the subsurface sound speed are qualitatively correct.

  6. Parallel three-step phase-shifting digital holography.

    PubMed

    Awatsuji, Yasuhiro; Fujii, Atsushi; Kubota, Toshihiro; Matoba, Osamu

    2006-05-01

    We propose parallel three-step phase-shifting digital holography as a technique capable of noiseless instantaneous measurement of three-dimensional objects based on phase-shifting interferometry. The proposed digital holography carries out three-step phase shifting at the same time by using a phase-shifting array device located in the reference beam. The array device has a periodic three-step phase distribution, and its configuration is simplified compared with that required for conventional parallel phase-shifting digital holography. Therefore the optical system of the proposed parallel phase-shifting digital holography is more suitable for the realization of the proposed holography. We conduct both a numerical simulation and a preliminary experiment. The results of the simulation and experiment agree well with those of the conventional phase-shifting method and are superior to the results obtained by conventional digital holography by using the Fresnel transform alone. Thus the effectiveness of the proposed technique is verified.

  7. Two-dimensional Phase Unwrapping for Digital Holography

    DTIC Science & Technology

    2012-09-01

    Two-dimensional Phase Unwrapping for Digital Holography by Neal K. Bambha, Justin R. Bickford, and Karl K. Klett, Jr. ARL-TR-6225...1197 ARL-TR-6225 September 2012 Two-dimensional Phase Unwrapping for Digital Holography Neal K. Bambha, Justin R. Bickford, and Karl K...2. REPORT TYPE Final 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Two-dimensional Phase Unwrapping for Digital Holography 5a. CONTRACT

  8. Display holography an SPIE critical review of technology

    NASA Astrophysics Data System (ADS)

    Benton, S. A.

    1985-01-01

    Various techniques used in holographic imagery are presented. The prominent features, potentials, and limitations of the laser transmission ('Leith and Upatnieks') holography, the white light transmission ('rainbow' or 'Benton') holography, and the reflection ('Denisyuk') holography methods are discused. Special consideration is given to the practical technique of holographic stereograms, which permits accurate production of three-dimensional, magnified and minified, images of moving objects or moving images, and which is part of all three classes of holographic methods.

  9. Computer holography by means of the laser diodes

    NASA Astrophysics Data System (ADS)

    Borodin, Arthur N.; Ilchenko, Volodymyr; Malov, Alexander N.; Sychevskiy, Alexey V.

    2007-02-01

    A computer holography is the optical hologram recording on the CCD-matrix with digital reconstruction of the 2Dimages for the different volume object cross-sections. The possibility to use compact semiconductor laser diodes in the computer holography for 3D-scene registration is experimentally proved in the D. Gabor's scheme. For off axis hologram recording the S. Benton's scheme for holography using is suggested.

  10. Functional role of polar amino acid residues in Na+/H+ exchangers.

    PubMed Central

    Wiebe, C A; Dibattista, E R; Fliegel, L

    2001-01-01

    Na(+)/H(+) exchangers are a family of ubiquitous membrane proteins. In higher eukaryotes they regulate cytosolic pH by removing an intracellular H(+) in exchange for an extracellular Na(+). In yeast and Escherichia coli, Na(+)/H(+) exchangers function in the opposite direction to remove intracellular Na(+) in exchange for extracellular H(+). Na(+)/H(+) exchangers display an internal pH-sensitivity that varies with the different antiporter types. Only recently have investigations examined the amino acids involved in pH-sensitivity and in cation binding and transport. Histidine residues are good candidates for H(+)-sensing amino acids, since they can ionize within the physiological pH range. Histidine residues have been shown to be important in the function of the E. coli Na(+)/H(+) exchanger NhaA and in the yeast Na(+)/H(+) exchanger sod2. In E. coli, His(225) of NhaA may function to interact with, or regulate, the pH-sensory region of NhaA. In sod2, His(367) is also critical to transport and may be a functional analogue of His(225) of NhaA. Histidine residues are not critical for the function of the mammalian Na(+)/H(+) exchanger, although an unusual histidine-rich sequence of the C-terminal tail has some influence on activity. Other amino acids involved in cation binding and transport by Na(+)/H(+) exchangers are only beginning to be studied. Amino acids with polar side chains such as aspartate and glutamate have been implicated in transport activity of NhaA and sod2, but have not been studied in the mammalian Na(+)/H(+) exchanger. Further studies are needed to elucidate the mechanisms involved in pH-sensitivity and cation binding and transport by Na(+)/H(+) exchangers. PMID:11415429

  11. High precision phase-shifting electron holography

    PubMed

    Yamamoto; Kawajiri; Tanji; Hibino; Hirayama

    2000-01-01

    Today's information-oriented society requires high density and high quality magnetic recording media. The quantitative observation of fine magnetic structures by electron holography is greatly anticipated in the development of such new recording materials. However, the magnetic fields around particles <50 nm have not been observed, because the fields are too weak to observe in the usual way. Here we present a highly precise phase measurement technique: improved phase-shifting electron holography. Using this method, the electric field around a charged polystyrene latex particle (100 nm in diameter) and the magnetic field around iron particles (30 nm in diameter) are observed precisely. A precision of the reconstructed phase image of 2pi/300 rad is achieved in the image of the latex particle.

  12. Subaperture stitching interferometry based on digital holography

    NASA Astrophysics Data System (ADS)

    Pan, Feng; Lu, Xiaoyun; Dong, Bin; Ma, Xichao; Xiao, Wen

    2016-11-01

    A novel subaperture stitching interferometry based on digital holography is developed to measure the deformation of spherical surfaces. The subaperture measurement is performed by off-axis digital holography on single exposure. Then, the subaperture phase maps are obtained by digital holographic reconstruction, in which the phase aberration caused by position errors of each subaperture measurement is effectively compensated by the method of numerical parametric lens. After that, the full aperture phase map is retrieved by a subaperture stitching algorithm, in which the relative alignment errors of adjacent subapertures are eliminated with an iterative process of stitching optimization. The experiments demonstrate the feasibility and effectiveness of the proposed interferometry, which provides a rapid and robust way to measure spherical surfaces with high resolution and precision. A practical example is given to demonstrate the performance of this method. The stitching result shows good agreement with the full-aperture result.

  13. Imaging nanoparticles in cells by nanomechanical holography

    SciTech Connect

    Tetard, Laurene; Passian, Ali; Venmar, Katherine T; Lynch, Rachel M; Voy, Brynn H; Shekhawat, Gajendra; Dravid, Vinayak; Thundat, Thomas George

    2008-06-01

    Nanomaterials have potential medical applications, for example in the area of drug delivery, and their possible adverse effects and cytotoxicity are curently receiving attention1,2. Inhalation of nanoparticles is of great concern, because nanoparticles can be easily aerosolized. Imaging techniques that can visualize local populations of nanoparticles at nanometre resolution within the structures of cells are therefore important3. Here we show that cells obtained from mice exposed to single-walled carbon nanohorns can be probed using a scanning probe microscopy technique called scanning near field ultrasonic holography. The nanohorns were observed inside the cells, and this was further confirmed using micro Raman spectroscopy. Scanning near field ultrasonic holography is a useful technique for probing the interactions of engineered nanomaterials in biological systems, which will greatly benefit areas in drug delivery and nanotoxicology.

  14. Digital holography techniques for optical interference

    NASA Astrophysics Data System (ADS)

    Perez-Garcia, Benjamin; Gossman, David; Hernandez-Aranda, Raul I.; Forbes, Andrew

    2016-09-01

    In this work we revisit Young's experiment and show how it can be done with digital holography. We study different properties of light and show that depending on how light interferes, fringe patterns in other observables arise. We explain this conceptually and demonstrate how this can be implemented experimentally. We aid the reader with a tutorial-like approach and provide the necessary tools to easily perform the experiments.

  15. White Light Holography Using Flexible Membrane Mirrors

    NASA Astrophysics Data System (ADS)

    Warren, D.; King, W.; Waddell, P.; Raptodimos, T.

    1988-06-01

    White light transmission holograms have been made using revolutionary flexible membrane concave mirrors of variable focal length. These mirrors are used as collimators to produce and project conjugate imagery for making white light holograms. The era of super large scale white light holography with undistorted imagery and large angular field of view is predicted, based on current results and the availability of very wide plastic sheets suitable for use as the reflective membrane of the flexible mirrors.

  16. Quantitative phase microscopy with asynchronous digital holography.

    PubMed

    Chalut, Kevin J; Brown, William J; Wax, Adam

    2007-03-19

    We demonstrate a new method of measuring quantitative phase in imaging of biological materials. This method, asynchronous digital holography, employs knowledge of a moving fringe created by acousto-optic modulators to execute phase-shifting interferometry using two near-simultaneous interferograms. The method can be used to obtain quantitative phase images of dynamic biological samples on millisecond time scales. We present results on a standard sample, and on live cell samples.

  17. Medical Holography for Basic Anatomy Training

    DTIC Science & Technology

    2013-12-01

    current holographic technology is able to present high quality auto-stereoscopic (no-glasses) 30 visuals. Holography began in the 1940s, when Dennis ... Gabor invented the hologram and won the Nobel Prize for the achievement ( Gabor , 1948). Significant advances occurred when researchers created the...Investigating Geospatial Holograms for Special Weapons and Tactics Teams. Cartographic Perspectives, (63), 5-19. Gabor , D. (1948). A new

  18. Chaos in AdS2 Holography

    NASA Astrophysics Data System (ADS)

    Jensen, Kristan

    2016-09-01

    We revisit two-dimensional holography with the Sachdev-Ye-Kitaev models in mind. Our main result is to rewrite a generic theory of gravity near a two-dimensional anti-de Sitter spacetime throat as a novel hydrodynamics coupled to the correlation functions of a conformal quantum mechanics. This gives a prescription for the computation of n -point functions in the dual quantum mechanics. We thereby find that the dual is maximally chaotic.

  19. Multidimensional imaging using compressive Fresnel holography.

    PubMed

    Horisaki, Ryoichi; Tanida, Jun; Stern, Adrian; Javidi, Bahram

    2012-06-01

    We propose a generalized framework for single-shot acquisition of multidimensional objects using compressive Fresnel holography. A multidimensional object with spatial, spectral, and polarimetric information is propagated with the Fresnel diffraction, and the propagated signal of each channel is observed by an image sensor with randomly arranged optical elements for filtering. The object data are reconstructed using a compressive sensing algorithm. This scheme is verified with numerical experiments. The proposed framework can be applied to imageries for spectrum, polarization, and so on.

  20. Ultrarealistic imaging: the future of display holography

    NASA Astrophysics Data System (ADS)

    Bjelkhagen, Hans I.; Brotherton-Ratcliffe, David

    2014-11-01

    Ultrarealistic imaging is the science of producing images that faithfully recreate the light field surrounding an object, such that the unaided eye of a human observer cannot distinguish the difference between the original and the image. Recent technology improvements are now set to transform the fields of both analog and digital display holography, permitting both techniques to operate in the ultrarealistic regime. In particular, ultrarealistic analog holograms have now heralded the serious use of holography in such areas as museum display and cultural heritage protection. These full-color holograms are characterized by a substantially lower noise and a greater spectral fidelity. New recording systems, based on recent diode-pumped solid-state and semiconductor lasers combined with recording materials and processing, have been behind these improvements. Progress in illumination technology, however, has also led to a major reduction in display noise and to a significant increase in the clear image depth and brightness of holograms. Recent progress in one-step direct-write digital holography (DWDH) is now also opening the way to the creation of a new type of ultrarealistic display: the high virtual volume display. This is a large format full-parallax DWDH reflection hologram having a fundamentally larger clear image depth.

  1. Generalized phase-shifting digital holography for single-exposure

    NASA Astrophysics Data System (ADS)

    Nomura, Takanori; Imbe, Masatoshi

    2015-07-01

    Single exposure phase-shifting digital holography is mandatory for recording/analyzing dynamic phenomena. As one of the candidate for the single exposure phase-shifting digital holography is the wave-splitting phase-shifting digital holography. We have proposed generalized phase-shifting digital holography as one of the wave-splitting phase-shifting digital holography. In the digital holography, the phase-shift quantity, which corresponds to the difference between the phase quantities of the reference wave on the adjacent pixels is generalized different from ordinal wave-splitting methods. Owing to the generalized phase-shifting, we can use a random-phase wave as the reference wave. The proposed phase-shifting digital holography enables us to record a fully-complex field of a dynamic phenomena without dc and conjugate terms using a commercially available optical devices. The relation between the property of the reference wave and the quality of the reconstructed images are discussed. Experimental results are given to confirm the proposed phase-shifting digital holography.

  2. Display holography in the United Kingdom, 1994-1997

    NASA Astrophysics Data System (ADS)

    Benyon, Margaret

    1998-02-01

    This paper reports on developments in display holography in the UK since 1994, covering the activities of individual holographers and artists, small companies and larger commercial concerns. It also includes comments on reactions to the withdrawal of Agfa-Geveart Ltd from the production of silver-halide materials for holography.

  3. Acoustic Neuroma

    MedlinePlus

    ... search IRSA's site Unique Hits since January 2003 Acoustic Neuroma Click Here for Acoustic Neuroma Practice Guideline ... to microsurgery. One doctor's story of having an acoustic neuroma In August 1991, Dr. Thomas F. Morgan ...

  4. Ethereal presences in holography and photography

    NASA Astrophysics Data System (ADS)

    Richardson, M.; Byrne, Kay

    2007-02-01

    This paper examines the concept of the 'Presence of Absence' in post-mortem photography and holography, drawing upon both historical and lesser-known images as reference. To create a photographic negative one needs the presence of light to expose the light sensitive surface, be it glass, a polished plate or plastic. A hologram may also be created when a coherent light source, for example from a Laser, travels through a light sensitive material and falls upon the subject to be recorded. A holograph however, retains the optical qualities of both phase and amplitude, the memory of light. Both mediums recall, as it were, 'now absent moments', and confronts us with what is 'not there' as much as 'what is'. This paper examines the exploration of absence and presence in post-mortem photography and holography and it's a richly visceral visual language. A photonic syntax can interpret death as an elegant yet horrific aesthetic, the photograph may be beautify screened and yet obscene in its content. In essence one can be a voyeur, experiencing a mere visual whisper of the true nature of the subject. Our Victorian forefathers explored postmortem photography as an object of mourning, and at the close of the nineteenth century when Jack the Ripper had the inhabitants of White Chapel in a grip of fear, photography made its mark as a documentation of violent crime. Today, within contemporary photography, death is now presented within the confines of the 'Art Gallery', as a sensual, and at times, sensationalised art form. In exploring post-mortem imagery, both in holography and conventional photography, absence presents an aspect of death as startling in its unanimated form and detailed in its finite examination of mortality.

  5. Applications of digital holography to measurements and optical characterization

    NASA Astrophysics Data System (ADS)

    Sang, Xinzhu; Yu, Chongxiu; Yu, Miao; Hsu, Dashsiung

    2011-09-01

    With recent advances in high-speed computer and video capture technology, holographic films used in classical holography can be replaced with charged-coupled devices (CCD) and complementary metal-oxide-semiconductor (CMOS) image sensors to record and numerically reconstruct a hologram, which is now known as digital holography. Digital holography introduces something new to optical science. Wet chemical processing and other time-consuming procedures can be removed, so numerical recording and reconstruction can be realized in almost real time. It allows us to characterize the phase of a light field as well the intensity, and so the whole wave field can be measured and stored in a computer. Digital holography is expanding applications of holography and becoming a scientific and technological tool. Its use has now increased for measuring amplitude and the phase of object waves, displacement and three dimensional shape, particle distributions and motions, characterization of the refractive index and biological tissues, and vibration analysis, etc. Here, basic principles of digital holography for optical measurement and characterization are described. Taking into consideration the rapid advance in CCD and CMOS sensors as the background, the state-of-the-art applications of digital holography to optical measurement and characterization are presented.

  6. "Kunstwerk" in the age of holography

    NASA Astrophysics Data System (ADS)

    Öhlmann, Dietmar; Meulien Ohlmann, Odile

    2013-02-01

    In 2007 one auction shocked collectors and artists: Two art works of Rudie Berkhout were offered for one thousand dollars on eBay. The closing down of museums for holography in Cologne, New York and Washington DC paid a big price of respect for true art. Benjamin's vision about "Art in the Age of Mechanical Reproduction" found a new expression in abuse and ignorance. Beautiful sculptures of Art are reduced to "Holograms" like Rudie's "Cairo Aspect" placed in a rummage sale, covered by fingerprints of ignorance.

  7. Observation of magnetic multilayers by electron holography.

    PubMed

    Tanji, T; Hasebe, S; Nakagami, Y; Yamamoto, K; Ichihashi, M

    2004-02-01

    Magnetic structures of Co/Cu multilayers in cross section are observed by two kinds of electron holography: a Fourier method and a phase-shifting method, which is introduced briefly. The Fourier method can easily reconstruct wave functions and is applied to many specimens, whereas the phase-shifting method requires longer time for processing, but has a higher spatial resolution that permits us to discuss fine structures. Magnetization vectors in Co layers aligning parallel and separating into two blocks with antiparallel alignment are observed. Magnetic blurring on the boundary between Co and Cu in the reconstructed phase images is larger than the estimated atomic roughness.

  8. Optical vortex phase-shifting digital holography.

    PubMed

    Guo, Cheng-Shan; Cheng, Xin; Ren, Xiu-Yun; Ding, Jian-Ping; Wang, Hui-Tian

    2004-10-18

    We report a new optical vortex phase-shifting method for digital holography, in which an optical vortex mode is taken as the reference beam for holographic recording, and the required phase shifts are directly generated by rotating the vortex mode. In digital reconstruction, the complex amplitude of the object wave can be retrieved by use of the conventional phase shifting algorithm on condition that the digital illumination beam is replaced by an vortex beam with the same topological charge as the reference used. Both the theoretical analysis and experimental results demonstrate the feasibility of this approach.

  9. Art of color holography: pioneers in change

    NASA Astrophysics Data System (ADS)

    Richardson, Martin J.; Bjelkhagen, Hans I.

    2000-10-01

    The possibility to easily record full color holograms, (simply color holograms) has opened new possibilities for art holographers. This paper includes details concerning preparation of subject matter and its practical suitability for color holographic recordings from practical working sessions at ARTCAPI Atelier de Recherche Technique et de Creation Artistique en Physique et en Informatique in France. Martin Richardson as invited artist and Hans Bjelkhagen as scientist holographer describe color holography to a wider public audience through artistic display. Both directly recorded true color images and computer-generated images based on the ZEBRA printing technique are to be presented.

  10. Infrared digital holography for large objects investigation

    NASA Astrophysics Data System (ADS)

    Geltrude, A.; Locatelli, M.; Poggi, P.; Pelagotti, A.; Paturzo, M.; Ferraro, P.; Meucci, R.

    2011-05-01

    In this work we show several acquisition setups and techniques which make it possible to obtain holographic recording and reconstruction of large objects by means of Infrared Digital Holography (IDH). In previous works it was demonstrated that, using the long wavelength coherent radiation produced by a CO2 laser instead of visible radiation, it is possible to obtain advantages in terms of larger field of view and lower seismic noise sensitivity. The only drawback using this wavelength is represented by the low resolution of current recording devices in this spectral region. The reported methods may have industrial applications where investigation of large dimension samples is needed.

  11. EDITORIAL: Optical tomography and digital holography

    NASA Astrophysics Data System (ADS)

    Coupland, Jeremy; Lobera, Julia

    2008-07-01

    The articles in this special feature in Measurement Science and Technology concern exciting new developments in the field of digital holography—the process of electronically recording and numerically reconstructing an optical field [1]. Making use of the enormous advances in digital imaging and computer technology, digital holography is presented in a range of applications from fluid flow measurement and structural analysis to medical imaging. The science of digital holography rests on the foundations of optical holography, on the work of Gabor in the late 1940s, and on the development of laser sources in the 1960s, which made his vision a practical reality [2]. Optical holography, however, uses a photosensitive material, both to record a latent image and subsequently to behave as a diffractive optical element with which to reconstruct the incident field. In this way display holograms, using silver halide materials for example, can produce life-size images that are virtually indistinguishable from the object itself [3]. Digital holography, in contrast, separates the steps of recording and reconstruction, and the final image is most often in the form of a 3D computer model. Of course, television cameras have been used from the beginnings of holography to record interferometric images. However, the huge disparity between the resolution of holographic recording materials (more than 3000 cycles/mm) and television cameras (around 50 cycles/mm) was raised as a major concern by early researchers. TV holography, as it was sometimes called, generally recorded low numerical aperture (NA) holograms producing images with characteristically large speckle and was therefore more often referred to as electronic speckle pattern interferomery (ESPI) [4]. It is possible, however, to record large NA holograms on a sensor with restricted resolution by using an objective lens or a diverging reference wave [5]. This is generally referred to as digital holographic microscopy (DHM) since

  12. Improved processing for silver halide pulse holography

    NASA Astrophysics Data System (ADS)

    Mikhailov, Viktor N.; Son, Jung-Young; Grinevitskaya, Olga V.; Lee, Hyuk-Soo; Choi, Yong-Jin

    1996-04-01

    Using of an improved developer with optical latensification allowed to significantly increase exposure sensitivity of currently in use silver halide materials. Transmission large-scale holograms (30 X 40 cm2) of diffused objects have been recorded under pulse exposure of about 6.5 X 10-6 J/cm2 for VRP and of about 2 X 10-6 J/cm2 for Agfa-Gavaert 8E56HD, in both cases without appreciable contrast deterioration. Results of the first experiments on pulse reflection holography are also discussed.

  13. Multi-field inflation from holography

    SciTech Connect

    Garriga, Jaume; Urakawa, Yuko; Skenderis, Kostas E-mail: K.Skenderis@soton.ac.uk

    2015-01-01

    We initiate the study of multi-field inflation using holography. Bulk light scalar fields correspond to nearly marginal operators in the boundary theory and the dual quantum field theory is a deformation of a CFT by such operators. We compute the power spectra of adiabatic and entropy perturbations in a simple model and find that the adiabatic curvature perturbation is not conserved in the presence of entropy perturbations but becomes conserved when the entropy perturbations are set to zero or the model is effectively a single scalar model, in agreement with expectations from cosmological perturbation theory.

  14. A system of enlarging visual field and viewing zone simultaneously for electro-holography

    NASA Astrophysics Data System (ADS)

    Nagai, Toshiaki; Yabe, Yoshiaki; Sakamoto, Yuji

    2007-02-01

    It is difficult to realize a practical electro-holography, because visual field and viewing zone are limited, which are very narrow to see by both eyes. The problems are caused by the resolution of devices that display fringe pattern, such as on a SLM (spatial light modulator) and an AOM (acoustic optic modulator). A low resolution of device occurs ghost images that are high-order diffraction images of reconstructed images. Therefore the ghost images prevent large visual field and large viewing zone. We propose new configuration of electro-holography using LCD (liquid crystal display) that enlarges visual field and viewing zone simultaneously. The system consists of an array of reconstruction lights, LCD, electro-shutter that is located between SLM and viewer. It is possible to prevent the rays from the ghost images by the shutter, to choose appropriate positions of both a reconstruction light in array and an aperture of electro-shutter. It shows viewers the original 3D objects without ghosts. Switching the combination of positions of reconstruction light and aperture of shutter for all fringe patterns synchronously is possible to see no-ghost images from any point of view. Furthermore, to switching very fast by time-division multiplexing, we can get large visual field and large viewing zone simultaneously. To verify the principle of the method, we made a system and carried out the experiments. In this paper, we discuss the method and the experimental results.

  15. Uncertainty-managed phase-shifting digital holography.

    PubMed

    Hahn, Joonku; Kim, Hwi

    2012-11-01

    Phase-shifting digital holography is a digital measurement technology of a complex optical field profile that uses focal plane array detectors without the loss of bandwidth. It has been known that the accuracy of phase-shifting digital holography is limited mainly by the phase tolerance of reference. In this Letter, it is revealed that the uncertainty in an expected signal is highly dependent on the phase of the signal itself, as well as the phase tolerance of the reference. Based on the uncertainty analysis, we propose a novel scheme of phase-shifting digital holography that exploits an uncertainty property to enhance the measurement accuracy even under significant reference phase tolerance.

  16. Polarization manipulation in single refractive prism based holography lithography

    NASA Astrophysics Data System (ADS)

    Xiong, Wenjie; Xu, Yi; Xiao, Yujian; Lv, Xiaoxu; Wu, Lijun

    2015-01-01

    We propose theoretically and demonstrate experimentally a simple but effective strategy for polarization manipulation in single refractive prism based holographic lithography. By tuning the polarization of a single laser beam, we can obtain the pill shape interference pattern with a high-contrast where a complex optical setup and multiple polarizers are needed in the conventional holography lithography. Fabrication of pill shape two-dimensional polymer photonic crystals using one beam and one shoot holography lithography is shown as an example to support our theoretical results. This integrated polarization manipulation technique can release the crucial stability restrictions imposed on the multiple beams holography lithography.

  17. High-resolution imaging using endoscopic holography

    NASA Astrophysics Data System (ADS)

    Bjelkhagen, Hans I.

    1990-08-01

    Endoscopic holography or endoholography combines the features of endoscopy and holography. The purpose of endoholographic imaging is to provide the physician with a unique means of extending diagnosis by providing a life-like record of tissue. Endoholographic recording will provide means for microscopic examination of tissue and in some cases may obviate the need to excise specimens for biopsy. In this method holograms which have the unique properties of three-dimensionality large focal depth and high resolution are made with a newly designed endoscope. The endoscope uses a single-mode optical fiber for illumination and single-beam reflection holograms are recorded in close contact with the tissue at the distal end of the endoscope. The holograms are viewed under a microscope. By using the proper combinations of dyes for staining specific tissue types with various wavelengths of laser illumination increased contrast on the cellular level can be obtained. Using dyes such as rose bengal in combination with the 514. 5 nm line of an argon ion laser and trypan blue or methylene blue with the 647. 1 nm line of a krypton ion laser holograms of the stained colon of a dog showed the architecture of the colon''s columnar epithelial cells. It is hoped through chronological study using this method in-vivo an increased understanding of the etiology and pathology of diseases such as Crohn''s diseases colitis proctitis and several different forms of cancer will help to their control. 1.

  18. Stückelberg formulation of holography

    NASA Astrophysics Data System (ADS)

    Dvali, Gia; Gomez, Cesar; Wintergerst, Nico

    2016-10-01

    We suggest that holography can be formulated in terms of the information capacity of the Stückelberg degrees of freedom that maintain gauge invariance of the theory in the presence of an information boundary. These Stückelbergs act as qubits that account for a certain fraction of quantum information. Their information capacity is measured by the ratio of the inverse Stückelberg energy gap to the size of the system. Systems with the smallest gap are maximally holographic. For massless gauge systems this information measure is universally equal to the inverse coupling evaluated at the systems' length scale. In this language it becomes very transparent why the Stückelberg information capacity of black holes saturates the Bekenstein bound and accounts for the entire information of the system. The physical reason is that the strength of quantum interaction is bounded from below by the gravitational coupling, which scales as area. Observing the striking similarity between the scalings of the energy gap of the boundary Stückelberg modes and the Bogoliubov modes of critical many-body systems, we establish a connection between holography and quantum criticality through the correspondence between these modes.

  19. Massively parallel X-ray holography

    SciTech Connect

    Spence, John C.H; Marchesini, Stefano; Boutet, Sebastien; Sakdinawat, Anne E.; Bogan, Michael J.; Bajt, Sasa; Barty, Anton; Chapman, Henry N.; Frank, Matthias; Hau-Riege, Stefan P.; Szöke, Abraham; Cui, Congwu; Shapiro, David A.; Howells, MAlcolm R.; Shaevitz, Joshua W; Lee, Joanna Y.; Hajdu, Janos; Seibert, Marvin M.

    2008-08-01

    Advances in the development of free-electron lasers offer the realistic prospect of nanoscale imaging on the timescale of atomic motions. We identify X-ray Fourier-transform holography1,2,3 as a promising but, so far, inefficient scheme to do this. We show that a uniformly redundant array4 placed next to the sample, multiplies the efficiency of X-ray Fourier transform holography by more than three orders of magnitude, approaching that of a perfect lens, and provides holographic images with both amplitude- and phase-contrast information. The experiments reported here demonstrate this concept by imaging a nano-fabricated object at a synchrotron source, and a bacterial cell with a soft-X-ray free-electron laser, where illumination by a single 15-fs pulse was successfully used in producing the holographic image. As X-ray lasers move to shorter wavelengths we expect to obtain higher spatial resolution ultrafast movies of transient states of matter

  20. Introductory overview of holography and speckle

    NASA Astrophysics Data System (ADS)

    Parker, David E.

    1990-10-01

    The purpose of this paper is to provide a nonmathematical overview of holographic and speckle interferometry. This provides information necessary for those participants with little or no background in these areas to understand the application papers in the Holography Speckle session of ICALEO''89. Holography A hologram is an optical device which is capable of producing threedimensional images. The word hologram stems from the Greek root holos which means whole complete or entire and the word gram which means message. Thus a hologram is a complete record of a scene or object. The first hologram was produced by Dennis Gabor in 1948. In 1971 he won the Nobel Prize for his work. Leith and Upatnieks produced the first holograms using a laser in the early 1960''s. In conventional photography the light reflected from a scene is focused by a camera lens onto a photographic emulsion. The variation in irradiance of the light reaching the emulsion is related only to the amplitude of the electric field due to the light. To produce three-dimensional images a hologram records information about both the amplitude and phase of light reflected from a scene or object. Production Hologram Figure 1 is a sketch of a system which can be used to produce optical holograms. A laser operating in the TEM mode is used as a light source. A continuous wave or a pulsed laser can be

  1. Compressed digital holography: from micro towards macro

    NASA Astrophysics Data System (ADS)

    Schretter, Colas; Bettens, Stijn; Blinder, David; Pesquet-Popescu, Béatrice; Cagnazzo, Marco; Dufaux, Frédéric; Schelkens, Peter

    2016-09-01

    signal processing methods from software-driven computer engineering and applied mathematics. The compressed sensing theory in particular established a practical framework for reconstructing the scene content using few linear combinations of complex measurements and a sparse prior for regularizing the solution. Compressed sensing found direct applications in digital holography for microscopy. Indeed, the wave propagation phenomenon in free space mixes in a natural way the spatial distribution of point sources from the 3-dimensional scene. As the 3-dimensional scene is mapped to a 2-dimensional hologram, the hologram samples form a compressed representation of the scene as well. This overview paper discusses contributions in the field of compressed digital holography at the micro scale. Then, an outreach on future extensions towards the real-size macro scale is discussed. Thanks to advances in sensor technologies, increasing computing power and the recent improvements in sparse digital signal processing, holographic modalities are on the verge of practical high-quality visualization at a macroscopic scale where much higher resolution holograms must be acquired and processed on the computer.

  2. Holography for automotive head-up displays

    NASA Astrophysics Data System (ADS)

    Ramsbottom, Andrew P.; Sergeant, Shirley A.; Sheel, David W.

    1992-05-01

    There is increasing interest in head-up-displays (HUDs) for automotive use. A number of technologies could be employed for the combiner function including plain glass reflection, dielectric enhancement, and holography. This paper will consider the potential role for conformal holography as the combiner element by initially reviewing the system requirements from an optical design view, how these differ significantly from an avionic HUD, and how they relate to material characteristics and process features. This will involve a consideration in some detail of the effects of specified hologram properties and lamination features on the optical performance and image characteristic of a car HUD. In particular, we shall examine such features as hologram efficiency, bandwidth, tuning position, environmental stability, tolerances, and film lamination effects and how these may influence the key optical characteristics of the image, i.e., distortions, blur, brightness, double imaging (separation and contrast) outside world view, etc.. A theoretical model based on Kogelnik coupled wave theory will be used to illustrate the various tradeoffs between hologram properties and process, image features, and display characteristics (bandwidth, polarization, etc.). This analysis will be related to properties of currently available holographic materials with reference to recent experimental work.

  3. Simulated electron holography of PSD particles

    NASA Astrophysics Data System (ADS)

    Conbhuí, Pádraig Ó.; Williams, Wyn; Nagy, Les

    2016-04-01

    Electron holography is an experimental technique that is capable of observing magnetic microstructures on the same scale as can be determined using numerical modeling and thus bridge the gap between experimental measurements and theory. I will present a technique for simulating holographic images from the results of micromagnetic models and demonstrate an easily used tool for generating holograms on the fly in an interactive environment (ie in ParaView). Since holography flattens 3D information onto a 2D image, some useful information can be lost. By looking at some examples of holograms of interesting 3D magnetizations (ie PSD structures), particularly how they change as they're rotated, along with comparisons of different structures, I will examine what information can be retrieved and what might be lost. The existance of an external dipole can be indicative of an in-plane component of a seemingly out-of-plane vortex core. It is also seen, however, that two quite different structures (in this case a [111] vortex core and a [111] uniform magnetization) can sometimes be quite indistinguishable.

  4. High thermopower and potential thermoelectric properties of crystalline LiH and NaH

    NASA Astrophysics Data System (ADS)

    Zhao, Yinchang; Dai, Zhenhong; Zhang, Chao; Lian, Chao; Zeng, Shuming; Li, Geng; Meng, Sheng; Ni, Jun

    2017-01-01

    We use first-principles calculations combined with the Boltzmann transport equation and semiclassical analysis to investigate the thermal conductivity κ , electrical conductivity σ , and thermopower S of crystalline LiH and NaH. Remarkably, the calculated S is extraordinarily high while the lattice thermal conductivity κL is fairly low, which, as a result, leads to a much high thermoelectric power factor σ S2 and good thermoelectric properties, with the figure of merit z T even larger than 1.5 in the p -type doped NaH. Further analyses reveal that (i) the large band gap and the flat band around the Fermi level cause the high S and (ii) strong anharmonic phonon scatterings and relevant phonon group velocities result in the low κL in these light materials. Our results support that crystalline LiH and NaH may be potential materials for thermoelectric applications.

  5. High speed 3D surface inspection with digital holography

    NASA Astrophysics Data System (ADS)

    Brunn, Andreas; Aspert, Nicolas; Cuche, Etienne; Emery, Yves; Ettemeyer, Andreas

    2013-01-01

    Digital holography has proven its ability to acquire high accuracy full field 3D data with one single image acquisition. This means that in principle this technique offers the chance to perform 3D serial inspection processes, as well. However, one limitation in digital holography is its limited ability to measure rough surfaces. In the presence of rough surfaces, the magnification of the image has to be increased to capture the required phase information on each camera pixel. However, this leads to significant reduction of inspection speed. If low magnification is selected, the rough surface produces speckles which cannot be treated properly by digital holography algorithms. In this paper, we describe the extension of digital holography to rough surface applications using speckle interferometry technique. This technique is capable of fast inspection of rough surfaces with sub-micrometer accuracy. The principle of this approach is shown and a practical application for 3D surface inspection of wafer cutting processes is given.

  6. Theoretical scheme for simultaneously observing forward-backward photoelectron holography.

    PubMed

    Du, Hongchuan; Wu, Hongmei; Wang, Huiqiao; Yue, Shengjun; Hu, Bitao

    2016-02-15

    Photoelectron angular momentum distribution of He+ driven by a few-cycle laser is investigated numerically. We simultaneously observe two dominant interference patterns with one shot of lasers by solving the 3D time-dependent Schrodinger equation. Analysis of a semiclassical model identifies these two interference patterns as two types of photoelectron holography. The interference pattern with Pz0 is a type of forward rescattering holography, which comes from the interference between direct (reference) and rescattered (signal) forward electrons ionized in the same quarter-cycle. The interference pattern with Pz<0 is a type of backward rescattering holography, which comes from the interference between a direct electron ionized in the third quarter-cycle and rescattered backward electron ionized in the first quarter-cycle. Moreover, we propose a method to distinguish this backward rescattering holography and intracycle interference patterns of direct electrons.

  7. Absorbing New Subjects: Holography as an Analog of Photography

    NASA Astrophysics Data System (ADS)

    Johnston, Sean F.

    2006-05-01

    I discuss the early history of holography and explore how perceptions, applications, and forecasts of the subject were shaped by prior experience. I focus on the work of Dennis Gabor (1900 1979) in England,Yury N. Denisyuk (b. 1924) in the Soviet Union, and Emmett N. Leith (1927 2005) and Juris Upatnieks (b. 1936) in the United States. I show that the evolution of holography was simultaneously promoted and constrained by its identification as an analog of photography, an association that influenced its assessment by successive audiences of practitioners, entrepreneurs, and consumers. One consequence is that holography can be seen as an example of a modern technical subject that has been shaped by cultural influences more powerfully than generally appreciated. Conversely, the understanding of this new science and technology in terms of an older one helps to explain why the cultural effects of holography have been more muted than anticipated by forecasters between the 1960s and 1990s.

  8. Optical HAAR Wavelet Transforms using Computer Generated Holography

    DTIC Science & Technology

    1992-12-17

    This research introduces an optical implementation of the continuous wavelet transform to filter images. The wavelet transform is modeled as a...continuous wavelet transform was performed and that the results compared favorably to digital simulation. Wavelets, Holography, Optical correlators.

  9. Fresnel Lens Scatter Plate for Data Reduction Holography.

    DTIC Science & Technology

    In the patent the holographic apparatus and method uses a Fresnel lens as a scatter plate in data reduction holography. A second embodiment uses a Fresnel lens in series with a fly’s eye lens array.

  10. Particle and flow field holography: A critical survey

    NASA Technical Reports Server (NTRS)

    Trolinger, James D.

    1987-01-01

    A brief background is provided for the fields of particle and flow visualization holography. A summary of methods currently in use is given, followed by a discussion of more recent and unique applications. The problem of data reduction is discussed. A state of the art summary is then provided with a prognosis of the future of the field. Particle and flow visualization holography are characterized as powerful tools currently in wide use and with significant untapped potential.

  11. Incoherent digital holography with phase-only spatial light modulators

    NASA Astrophysics Data System (ADS)

    Rosen, Joseph; Kelner, Roy; Kashter, Yuval

    2015-10-01

    Today, spatial light modulators (SLMs) offer the world of digital holography a robust technology that can be incorporated into hologram recorders. This review surveys recent developments related to the role of SLMs in a family of incoherent digital hologram recorders termed Fresnel incoherent correlation holography (FINCH). Two systems branching out from FINCH, and discussed herein, are a confocal version of FINCH and a synthetic aperture FINCH-based system.

  12. Quantification of phnAc and nahAc in contaminated New Zealand soils by competitive PCR

    SciTech Connect

    Laurie, A.D.; Lloyd-Jones, G.

    2000-05-01

    Unculturable polycyclic aromatic hydrocarbon (PAH)-degrading bacteria are a significant reservoir of the microbial potential to catabolize low-molecular-weight PAHs. The population of these bacteria is larger than the population of nah-like bacteria that are the dominant organisms in culture-based studies. The authors used the recently described phn genes of Burkholderia sp. strain RP007, which feature only rarely in culture-based studies, as an alternative genotype for naphthalene and phenanthrene degradation and compared this genotype with the genotypically distinct but ubiquitous nah-like class in different soils. Competitive PCR quantification of phnAc and nahAc, which encode the iron sulfur protein large ({alpha}) subunits of PAH dioxygenases in nah-like and phn catabolic operons, revealed that the phn genotype can have a greater ecological significance than the nah-like genotype.

  13. Neural-net Processed Electronic Holography for Rotating Machines

    NASA Technical Reports Server (NTRS)

    Decker, Arthur J.

    2003-01-01

    This report presents the results of an R&D effort to apply neural-net processed electronic holography to NDE of rotors. Electronic holography was used to generate characteristic patterns or mode shapes of vibrating rotors and rotor components. Artificial neural networks were trained to identify damage-induced changes in the characteristic patterns. The development and optimization of a neural-net training method were the most significant contributions of this work, and the training method and its optimization are discussed in detail. A second positive result was the assembly and testing of a fiber-optic holocamera. A major disappointment was the inadequacy of the high-speed-holography hardware selected for this effort, but the use of scaled holograms to match the low effective resolution of an image intensifier was one interesting attempt to compensate. This report also discusses in some detail the physics and environmental requirements for rotor electronic holography. The major conclusions were that neural-net and electronic-holography inspections of stationary components in the laboratory and the field are quite practical and worthy of continuing development, but that electronic holography of moving rotors is still an expensive high-risk endeavor.

  14. Simultaneous Conoscopic Holography and Raman Spectroscopy

    NASA Technical Reports Server (NTRS)

    Schramm, Harry F.; Kaiser, Bruce

    2005-01-01

    A new instrument was developed for chemical characterization of surfaces that combines the analytical power of Raman spectroscopy with the three-dimensional topographic information provided by conoscopic holography. The figure schematically depicts the proposed hybrid instrument. The output of the conoscopic holographic portion of the instrument is a topographical map of the surface; the output of the Raman portion of the instrument is hyperspectral Raman data, from which the chemical and/or biological composition of the surface would be deduced. By virtue of the basic principles of design and operation of the instrument, the hyperspectral image data would be inherently spatially registered with the topographical data. In conoscopic holography, the object and reference beams of classical holography are replaced by the ordinary and extraordinary components generated by a single beam traveling through a birefringent, uniaxial crystal. In the basic conoscopic configuration, a laser light is projected onto a specimen and the resulting illuminated spot becomes a point source of diffuse light that propagates in every direction. The laser beam is rasterscanned in two dimensions (x and y) perpendicular to the beam axis (z), and at each x,y location, the pattern of interference between the ordinary and extraordinary rays is recorded. The recorded interferogram constitutes the conoscopic hologram. Of particular significance for the proposed instrument is that the conoscopic hologram contains information on the z coordinate (height) of the illuminated surface spot. Hence, a topographical map of the specimen is constructed point-by-point by rastering the laser beam in the x and y directions and correlating the x and y coordinates with the z information obtained from the interferograms. Conoscopic imaging is an established method, and conoscopic laboratory instruments for surface metrology are commercially available. In Raman spectroscopy of a surface, one measures the spectrum

  15. When holography meets coherent diffraction imaging.

    PubMed

    Latychevskaia, Tatiana; Longchamp, Jean-Nicolas; Fink, Hans-Werner

    2012-12-17

    The phase problem is inherent to crystallographic, astronomical and optical imaging where only the intensity of the scattered signal is detected and the phase information is lost and must somehow be recovered to reconstruct the object's structure. Modern imaging techniques at the molecular scale rely on utilizing novel coherent light sources like X-ray free electron lasers for the ultimate goal of visualizing such objects as individual biomolecules rather than crystals. Here, unlike in the case of crystals where structures can be solved by model building and phase refinement, the phase distribution of the wave scattered by an individual molecule must directly be recovered. There are two well-known solutions to the phase problem: holography and coherent diffraction imaging (CDI). Both techniques have their pros and cons. In holography, the reconstruction of the scattered complex-valued object wave is directly provided by a well-defined reference wave that must cover the entire detector area which often is an experimental challenge. CDI provides the highest possible, only wavelength limited, resolution, but the phase recovery is an iterative process which requires some pre-defined information about the object and whose outcome is not always uniquely-defined. Moreover, the diffraction patterns must be recorded under oversampling conditions, a pre-requisite to be able to solve the phase problem. Here, we report how holography and CDI can be merged into one superior technique: holographic coherent diffraction imaging (HCDI). An inline hologram can be recorded by employing a modified CDI experimental scheme. We demonstrate that the amplitude of the Fourier transform of an inline hologram is related to the complex-valued visibility, thus providing information on both, the amplitude and the phase of the scattered wave in the plane of the diffraction pattern. With the phase information available, the condition of oversampling the diffraction patterns can be relaxed, and the

  16. Quantum probabilities for inflation from holography

    SciTech Connect

    Hartle, James B.; Hawking, S.W.; Hertog, Thomas E-mail: S.W.Hawking@damtp.cam.ac.uk

    2014-01-01

    The evolution of the universe is determined by its quantum state. The wave function of the universe obeys the constraints of general relativity and in particular the Wheeler-DeWitt equation (WDWE). For non-zero Λ, we show that solutions of the WDWE at large volume have two domains in which geometries and fields are asymptotically real. In one the histories are Euclidean asymptotically anti-de Sitter, in the other they are Lorentzian asymptotically classical de Sitter. Further, the universal complex semiclassical asymptotic structure of solutions of the WDWE implies that the leading order in h-bar quantum probabilities for classical, asymptotically de Sitter histories can be obtained from the action of asymptotically anti-de Sitter configurations. This leads to a promising, universal connection between quantum cosmology and holography.

  17. Electromagnetic induction holography imaging for stroke detection.

    PubMed

    Wang, Lulu

    2017-02-01

    This paper presents the application of the electromagnetic induction holography (EMIH) approach to imaging the electromagnetic activity of the brain, with a particular focus on stroke detection. An integral equation formulation is presented to describe the scattered magnetic field from the distribution of optically small dielectric and magnetic objects of arbitrary shapes adsorbed onto a planar electromagnetic substrate. A numerical computer model was developed in a MATLAB environment to validate the theory. Several realistic human head models were developed to investigate the detectability of strokes with the multi-channel EMIH system. Small strokes can be clearly identified with the correct location and size in the reconstructed head images. The simulation results demonstrated the feasibility of detecting and imaging small strokes using the approach.

  18. Adaptive holography for optical sensing applications

    NASA Astrophysics Data System (ADS)

    Residori, S.; Bortolozzo, U.; Peigné, A.; Molin, S.; Nouchi, P.; Dolfi, D.; Huignard, J. P.

    2016-03-01

    Adaptive holography is a promising method for high sensitivity phase modulation measurements in the presence of slow perturbations from the environment. The technique is based on the use of a nonlinear recombining medium, here an optically addressed spatial light modulator specifically realized to operate at 1.55 μm. Owing to the physical mechanisms involved, the interferometer adapts to slow phase variations within a range of 5-10 Hz, thus filtering out low frequency noise while transmitting higher frequency phase modulations. We present the basic principles of the adaptive interferometer and show that it can be used in association with a sensing fiber in order to detect phase modulations. Finally, a phase-OTDR architecture using the adaptive holographic interferometer is presented and shown to allows the detection of localized perturbations along the sensing fiber.

  19. X-ray holography in-flight

    NASA Astrophysics Data System (ADS)

    Gorkhover, Tais; Ulmer, Anatoli; Ferguson, Ken; Bucher, Max; Ekeberg, Tomas; Hantke, Max; Daurer, Benedikt; Nettelblad, Carl; Bielecki, Johan; Faigel, Guila; Hasse, Dirk; Morgan, Andrew; Mühlig, Kerstin; Seibert, Marvin; Chapman, Henry; Hajdu, Janos; Maia, Filipe; Moeller, Thomas; Bostedt, Christoph

    2016-05-01

    The advent of X-ray free-electron lasers, delivering ultra intense femtosecond X-ray flashes, opens the door for structure determination of single nanoparticles and biosamples with single shots. The first X-ray diffraction imaging experiments at LCLS delivered promising results on samples in the gas phase. However, the reconstruction of non-periodic structures is still challenging due to the loss of phase information. Meanwhile, X-ray holographic approaches allow for recording the phase directly into the diffraction image. In my talk, I will present the first successful proof-of-principle experiment for ``in-flight''-holography with free viruses. Our experiments pave the way for unique studies on levitating nanospecimen that are of central interest in several scientific communities including atmosphere research, chemistry, material sciences, and studies on matter under extreme conditions.

  20. Very high-speed digital holography

    NASA Astrophysics Data System (ADS)

    Pérez López, Carlos; Mendoza Santoyo, Fernando; Rodríguez Vera, Ramón; Moreno, David; Barrientos, Bernardino

    2006-08-01

    It is reported for the first time the use of a high speed camera in digital holography with an out of plane sensitivity. The camera takes the image plane holograms of a cw laser illuminated rectangular framed polyester material at a rate of 5000 per second, that is a spacing of 200 microseconds between holograms, and 512 by 500 pixels at 10 bit resolution. The freely standing object has a random movement due to non controlled environmental air currents. As is usual with this technique each digital hologram is Fourier processed in order to obtain upon comparison with a consecutive digital hologram the phase map of the displacement. High quality results showing the amplitude and direction of the random movement are presented.

  1. Phase-shifting color digital holography.

    PubMed

    Yamaguchi, Ichirou; Matsumura, Tatsuki; Kato, Jun-Ichi

    2002-07-01

    Digital holography with a three-wavelength laser and a color CCD has been demonstrated. With the phase shifting of the reference beam, in-line holograms for three wavelengths are recorded simultaneously for derivation of the complex amplitude at each wavelength, and then the three monochromatic images are reconstructed and combined into full-color images in the computer. Laser power variation for wavelengths can be compensated for in the reconstruction process. We have compared the images reconstructed by two algorithms using a single Fourier transformation and a convolution with each other by both experiments and numerical simulations. Phase-shifting errors arising at two of the three wavelengths have proved not to cause serious deterioration of the reconstructed images.

  2. Remote metrology by comparative digital holography

    SciTech Connect

    Baumbach, Torsten; Osten, Wolfgang; Kopylow, Christoph von; Jueptner, Werner

    2006-02-10

    A method for the remote comparison of objects with regard to their shape or response to a load is presented. The method allows interferometric sensitivity for comparing objects with different microstructure. In contrast to the well-known incoherent techniques based on inverse fringe projection this new approach uses the coherent optical wave field of the master object as a mask for the illumination of the sample object. The coherent mask is created by digital holography to allow instant access to the complete optical information of the master object at any place desired. The mask is reconstructed by a spatial light modulator (SLM). The optical reconstruction of digital holograms with SLM technology allows modification of reconstructed wavefronts with respect to improvement of image quality, the skilled introduction of additional information about the object (augmented reality), and the alignment of the master and test object.

  3. Optical scanning holography for stereoscopic display

    NASA Astrophysics Data System (ADS)

    Liu, Jung-Ping; Wen, Hsuan-Hsuan

    2016-10-01

    Optical Scanning Holography (OSH) is a scanning-type digital holographic recording technique. One of OSH's most important properties is that the OSH can record an incoherent hologram, which is free of speckle and thus is suitable for the applications of holographic display. The recording time of a scanning hologram is proportional to the sampling resolution. Hence the viewing angle as well as the resolution of a scanning hologram is limited for avoid too long recording. As a result, the viewing angle is not large enough for optical display. To solve this problem, we recorded two scanning holograms at different viewing angles. The two holograms are synthesized to a single stereoscopic hologram with two main viewing angles. In displaying, two views at the two main viewing angles are reconstructed. Because both views contain full-depth-resolved 3D scenes, the problem of accommodation conflict in conventional stereogram is avoided.

  4. Holography for Schrödinger backgrounds

    NASA Astrophysics Data System (ADS)

    Guica, Monica; Skenderis, Kostas; Taylor, Marika; van Rees, Balt C.

    2011-02-01

    We discuss holography for Schrödinger solutions of both topologically massive gravity in three dimensions and massive vector theories in ( d + 1) dimensions. In both cases the dual field theory can be viewed as a d-dimensional conformal field theory (two dimensional in the case of TMG) deformed by certain operators that respect the Schrödinger symmetry. These operators are irrelevant from the viewpoint of the relativistic conformal group but they are exactly marginal with respect to the non-relativistic conformal group. The spectrum of linear fluctuations around the background solutions corresponds to operators that are labeled by their scaling dimension and the lightcone momentum k v . We set up the holographic dictionary and compute 2-point functions of these operators both holographically and in field theory using conformal perturbation theory and find agreement. The counterterms needed for holographic renormalization are non-local in the v lightcone direction.

  5. Direct-to-digital holography and holovision

    DOEpatents

    Thomas, Clarence E.; Baylor, Larry R.; Hanson, Gregory R.; Rasmussen, David A.; Voelkl, Edgar; Castracane, James; Simkulet, Michelle; Clow, Lawrence

    2000-01-01

    Systems and methods for direct-to-digital holography are described. An apparatus includes a laser; a beamsplitter optically coupled to the laser; a reference beam mirror optically coupled to the beamsplitter; an object optically coupled to the beamsplitter, a focusing lens optically coupled to both the reference beam mirror and the object; and a digital recorder optically coupled to the focusing lens. A reference beam is incident upon the reference beam mirror at a non-normal angle, and the reference beam and an object beam are focused by the focusing lens at a focal plane of the digital recorder to form an image. The systems and methods provide advantages in that computer assisted holographic measurements can be made.

  6. Finite Inflation, Holography, and Dark Matter Annihilation

    NASA Astrophysics Data System (ADS)

    Scacco, Andrew Joseph

    This thesis covers work on theoretical cosmology relating to inflation, de Sitter space, dark matter annihilation, and holography. A unifying feature of all these topics is that all of them occur in de Sitter space or focus on epochs of the Universe when the spacetime was close to de Sitter and that all of them have some connection to holography. Chapter 1 provides a pedagogical introduction to the fundamentals of cosmology, inflation, de Sitter space, dark matter annihilation and entanglement entropy. Chapter 2 covers the impact on the causal entropic principle of dark matter annihilation that we find to have the greatest relevance at late times in the future when the dark energy has driven the universe to be asymptotically de Sitter. In this chapter we estimate holographically preferred dark matter properties for a range of assumptions. Chapter 3 covers holographic bounds in models of finite inflation, specifically the Banks-Fischler bound and de Sitter equilibrium. The assumptions in each of these models are explored in detail and some interesting new connections are presented. Chapter 4 tests models of inflation with a fast-roll start that happen to satisfy the holographic bounds in Chapter 3 against cosmic microwave background data from Planck. We find a slight preference for a feature at the scale predicted by the Banks-Fischler bound though this preference is not found to be statistically significant. Chapter 5 contains a numerical computation of the holographic mutual information for an annular configuration of regions on a conformal field theory in de Sitter space using the AdS/CFT correspondence. This computation shows that the de Sitter space CFT entanglement entropy matches what would be expected from a Minkowski CFT and shows that the HRT conjecture works for this case.

  7. Electrogenic Cation Binding in the Electroneutral Na+/H+ Antiporter of Pyrococcus abyssi.

    PubMed

    Călinescu, Octavian; Linder, Mark; Wöhlert, David; Yildiz, Özkan; Kühlbrandt, Werner; Fendler, Klaus

    2016-12-23

    Na(+)/H(+) antiporters in the CPA1 branch of the cation proton antiporter family drive the electroneutral exchange of H(+) against Na(+) ions and ensure pH homeostasis in eukaryotic and prokaryotic organisms. Although their transport cycle is overall electroneutral, specific partial reactions are electrogenic. Here, we present an electrophysiological study of the PaNhaP Na(+)/H(+) antiporter from Pyrococcus abyssi reconstituted into liposomes. Positive transient currents were recorded upon addition of Na(+) to PaNhaP proteoliposomes, indicating a reaction where positive charge is rapidly displaced into the proteoliposomes with a rate constant of k >200 s(-1) We attribute the recorded currents to an electrogenic reaction that includes Na(+) binding and possibly occlusion. Subsequently, positive charge is transported out of the cell associated with H(+) binding, so that the overall reaction is electroneutral. We show that the differences in pH profile and Na(+) affinity of PaNhaP and the related MjNhaP1 from Methanocaldococcus jannaschii can be attributed to an additional negatively charged glutamate residue in PaNhaP. The results are discussed in the context of the physiological function of PaNhaP and other microbial Na(+)/H(+) exchangers. We propose that both, electroneutral and electrogenic Na(+)/H(+) antiporters, represent a carefully tuned self-regulatory system, which drives the cytoplasmic pH back to neutral after any deviation.

  8. Electrogenic Cation Binding in the Electroneutral Na+/H+ Antiporter of Pyrococcus abyssi*

    PubMed Central

    Călinescu, Octavian; Linder, Mark; Wöhlert, David; Yildiz, Özkan; Kühlbrandt, Werner

    2016-01-01

    Na+/H+ antiporters in the CPA1 branch of the cation proton antiporter family drive the electroneutral exchange of H+ against Na+ ions and ensure pH homeostasis in eukaryotic and prokaryotic organisms. Although their transport cycle is overall electroneutral, specific partial reactions are electrogenic. Here, we present an electrophysiological study of the PaNhaP Na+/H+ antiporter from Pyrococcus abyssi reconstituted into liposomes. Positive transient currents were recorded upon addition of Na+ to PaNhaP proteoliposomes, indicating a reaction where positive charge is rapidly displaced into the proteoliposomes with a rate constant of k >200 s−1. We attribute the recorded currents to an electrogenic reaction that includes Na+ binding and possibly occlusion. Subsequently, positive charge is transported out of the cell associated with H+ binding, so that the overall reaction is electroneutral. We show that the differences in pH profile and Na+ affinity of PaNhaP and the related MjNhaP1 from Methanocaldococcus jannaschii can be attributed to an additional negatively charged glutamate residue in PaNhaP. The results are discussed in the context of the physiological function of PaNhaP and other microbial Na+/H+ exchangers. We propose that both, electroneutral and electrogenic Na+/H+ antiporters, represent a carefully tuned self-regulatory system, which drives the cytoplasmic pH back to neutral after any deviation. PMID:27821589

  9. Sodium-Proton (Na(+)/H(+)) Antiporters: Properties and Roles in Health and Disease.

    PubMed

    Padan, Etana; Landau, Meytal

    2016-01-01

    The transmembranal Na(+)/H(+) antiporters transport sodium (or several other monovalent cations) in exchange for H(+) across lipid bilayers in all kingdoms of life. They are critical in pH homeostasis of the cytoplasm and/or organelles. A particularly notable example is the SLC9 gene family, which encodes Na(+)/H(+) exchangers (NHEs) in many species from prokaryotes to eukaryotes. In humans, these proteins are associated with the pathophysiology of various diseases. Yet, the most extensively studied Na(+)/H(+) antiporter is Ec-NhaA, the main Na(+)/H(+) antiporter of Escherichia coli.The crystal structure of down-regulated Ec-NhaA, determined at acidic pH, has provided the first structural insights into the antiport mechanism and pH regulation of an Na(+)/H(+) antiporter. It reveals a unique structural fold (called the NhaA fold) in which transmembrane segments (TMs) are organized in inverted-topology repeats, including two antiparallel unfolded regions that cross each other, forming a delicate electrostatic balance in the middle of the membrane. This unique structural fold (The NhaA fold) contributes to the cation binding site and facilitates the rapid conformational changes expected for Ec-NhaA. The NhaA fold has now been recognized to be shared by four Na(+)/H(+) antiporters (bacterial and archaeal) and a Na(+) symporter. Remarkably, no crystal structure of any of the human Na(+)/H(+) antiporters exists. Nevertheless, the Ec-NhaA crystal structure has enabled the structural modeling of NHE1, NHE9, and NHA2, three human plasmalemmal proteins that are members of the SLC9 family that are involved in human pathophysiology. Moreover, as outlined in this review, developments in the field, including cellular and biophysical methods that enable ion levels and fluxes to be measured in intact cells as well as in knockout mice, have led to striking advances in the identification and characterization of plasma membrane NHEs and NHA.Very little is known about the endomembrane

  10. Functional characterization of a NapA Na(+)/H(+) antiporter from Thermus thermophilus.

    PubMed

    Furrer, Esther M; Ronchetti, Mirco F; Verrey, François; Pos, Klaas M

    2007-02-06

    Na(+)/H(+) antiporters are ubiquitous membrane proteins and play an important role in cell homeostasis. We amplified a gene encoding a member of the monovalent cation:proton antiporter-2 (CPA2) family (TC 2.A.37) from the Thermus thermophilus genome and expressed it in Escherichia coli. The gene product was identified as a member of the NapA subfamily and was found to be an active Na(+)(Li(+))/H(+) antiporter as it conferred resistance to the Na(+) and Li(+) sensitive strain E. coli EP432 (DeltanhaA, DeltanhaB) upon exposure to high concentration of these salts in the growth medium. Fluorescence measurements using the pH sensitive dye 9-amino-6-chloro-2-methoxyacridine in everted membrane vesicles of complemented E. coli EP432 showed high Li(+)/H(+) exchange activity at pH 6, but marginal Na(+)/H(+) antiport activity. Towards more alkaline conditions, Na(+)/H(+) exchange activity increased to a relative maximum at pH 8, where by contrast the Li(+)/H(+) exchange activity reached its relative minimum. Substitution of conserved residues D156 and D157 (located in the putative transmembrane helix 6) with Ala resulted in the complete loss of Na(+)/H(+) activity. Mutation of K305 (putative transmembrane helix 10) to Ala resulted in a compromised phenotype characterized by an increase in apparent K(m) for Na(+) (36 vs. 7.6 mM for the wildtype) and Li(+) (17 vs. 0.22 mM), In summary, the Na(+)/H(+) antiport activity profile of the NapA type transporter of T. thermophilus resembles that of NhaA from E. coli, whereas in contrast to NhaA the T. thermophilus NapA antiporter is characterized by high Li(+)/H(+) antiport activity at acidic pH.

  11. Acoustic Neuroma

    MedlinePlus

    An acoustic neuroma is a benign tumor that develops on the nerve that connects the ear to the brain. ... can press against the brain, becoming life-threatening. Acoustic neuroma can be difficult to diagnose, because the ...

  12. Acoustic Holographic Rendering with Two-dimensional Metamaterial-based Passive Phased Array.

    PubMed

    Xie, Yangbo; Shen, Chen; Wang, Wenqi; Li, Junfei; Suo, Dingjie; Popa, Bogdan-Ioan; Jing, Yun; Cummer, Steven A

    2016-10-14

    Acoustic holographic rendering in complete analogy with optical holography are useful for various applications, ranging from multi-focal lensing, multiplexed sensing and synthesizing three-dimensional complex sound fields. Conventional approaches rely on a large number of active transducers and phase shifting circuits. In this paper we show that by using passive metamaterials as subwavelength pixels, holographic rendering can be achieved without cumbersome circuitry and with only a single transducer, thus significantly reducing system complexity. Such metamaterial-based holograms can serve as versatile platforms for various advanced acoustic wave manipulation and signal modulation, leading to new possibilities in acoustic sensing, energy deposition and medical diagnostic imaging.

  13. Acoustic Holographic Rendering with Two-dimensional Metamaterial-based Passive Phased Array

    NASA Astrophysics Data System (ADS)

    Xie, Yangbo; Shen, Chen; Wang, Wenqi; Li, Junfei; Suo, Dingjie; Popa, Bogdan-Ioan; Jing, Yun; Cummer, Steven A.

    2016-10-01

    Acoustic holographic rendering in complete analogy with optical holography are useful for various applications, ranging from multi-focal lensing, multiplexed sensing and synthesizing three-dimensional complex sound fields. Conventional approaches rely on a large number of active transducers and phase shifting circuits. In this paper we show that by using passive metamaterials as subwavelength pixels, holographic rendering can be achieved without cumbersome circuitry and with only a single transducer, thus significantly reducing system complexity. Such metamaterial-based holograms can serve as versatile platforms for various advanced acoustic wave manipulation and signal modulation, leading to new possibilities in acoustic sensing, energy deposition and medical diagnostic imaging.

  14. Acoustic Holographic Rendering with Two-dimensional Metamaterial-based Passive Phased Array

    PubMed Central

    Xie, Yangbo; Shen, Chen; Wang, Wenqi; Li, Junfei; Suo, Dingjie; Popa, Bogdan-Ioan; Jing, Yun; Cummer, Steven A.

    2016-01-01

    Acoustic holographic rendering in complete analogy with optical holography are useful for various applications, ranging from multi-focal lensing, multiplexed sensing and synthesizing three-dimensional complex sound fields. Conventional approaches rely on a large number of active transducers and phase shifting circuits. In this paper we show that by using passive metamaterials as subwavelength pixels, holographic rendering can be achieved without cumbersome circuitry and with only a single transducer, thus significantly reducing system complexity. Such metamaterial-based holograms can serve as versatile platforms for various advanced acoustic wave manipulation and signal modulation, leading to new possibilities in acoustic sensing, energy deposition and medical diagnostic imaging. PMID:27739472

  15. Acoustic Seaglider

    DTIC Science & Technology

    2008-03-07

    a national naval responsibility. Acoustic sensors on mobile, autonomous platforms will enable basic research topics on temporal and spatial...problem and acoustic navigation and communications within the context of distributed autonomous persistent undersea surveillance sensor networks...Acoustic sensors on mobile, autonomous platforms will enable basic research topics on temporal and spatial coherence and the description of ambient

  16. Acoustic seal

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M. (Inventor)

    2006-01-01

    The invention relates to a sealing device having an acoustic resonator. The acoustic resonator is adapted to create acoustic waveforms to generate a sealing pressure barrier blocking fluid flow from a high pressure area to a lower pressure area. The sealing device permits noncontacting sealing operation. The sealing device may include a resonant-macrosonic-synthesis (RMS) resonator.

  17. Acoustic Seal

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M. (Inventor)

    2006-01-01

    The invention relates to a sealing device having an acoustic resonator. The acoustic resonator is adapted to create acoustic waveforms to generate a sealing pressure barrier blocking fluid flow from a high pressure area to a lower pressure area. The sealing device permits noncontacting sealing operation. The sealing device may include a resonant-macrosonic-synthesis (RMS) resonator.

  18. Parallel two-step phase-shifting digital holography.

    PubMed

    Awatsuji, Yasuhiro; Tahara, Tatsuki; Kaneko, Atsushi; Koyama, Takamasa; Nishio, Kenzo; Ura, Shogo; Kubota, Toshihiro; Matoba, Osamu

    2008-07-01

    We propose a parallel two-step phase-shifting digital holography technique capable of instantaneous measurement of three-dimensional objects, with a view toward measurement of dynamically moving objects. The technique is based on phase-shifting interferometry. The proposed technique carries out the two-step phase-shifting method at one time and can be optically implemented by using a phase-shifting array device located in the reference beam. The array device has a periodic two-step phase distribution, and its configuration is simplified compared with that required for three-step and four-step parallel phase-shifting digital holographies. Therefore the optical system of the proposed technique is more suitable for the realization of a parallel phase-shifting digital holography system. We conduct both a numerical simulation and a preliminary experiment in the proposed technique. The results of the simulation and the experiment agree well with those of sequential phase-shifting digital holography, and results are superior to those obtained by conventional digital holography using the Fresnel transform alone. Thus the effectiveness of the proposed technique is verified.

  19. Advanced Electron Holography Applied to Electromagnetic Field Study in Materials Science.

    PubMed

    Shindo, Daisuke; Tanigaki, Toshiaki; Park, Hyun Soon

    2016-11-17

    Advances and applications of electron holography to the study of electromagnetic fields in various functional materials are presented. In particular, the development of split-illumination electron holography, which introduces a biprism in the illumination system of a holography electron microscope, enables highly accurate observations of electromagnetic fields and the expansion of the observable area. First, the charge distributions on insulating materials were studied by using split-illumination electron holography and including a mask in the illumination system. Second, the three-dimensional spin configurations of skyrmion lattices in a helimagnet were visualized by using a high-voltage holography electron microscope. Third, the pinning of the magnetic flux lines in a high-temperature superconductor YBa2 Cu3 O7-y was analyzed by combining electron holography and scanning ion microscopy. Finally, the dynamic accumulation and collective motions of electrons around insulating biomaterial surfaces were observed by utilizing the amplitude reconstruction processes of electron holography.

  20. Dynamic imaging through turbid media based on digital holography.

    PubMed

    Li, Shiping; Zhong, Jingang

    2014-03-01

    Imaging through turbid media using visible or IR light instead of harmful x ray is still a challenging problem, especially in dynamic imaging. A method of dynamic imaging through turbid media using digital holography is presented. In order to match the coherence length between the dynamic object wave and the reference wave, a cw laser is used. To solve the problem of difficult focusing in imaging through turbid media, an autofocus technology is applied. To further enhance the image contrast, a spatial filtering technique is used. A description of digital holography and experiments of imaging the objects hidden in turbid media are presented. The experimental result shows that dynamic images of the objects can be achieved by the use of digital holography.

  1. Compressive Fresnel digital holography using Fresnelet based sparse representation

    NASA Astrophysics Data System (ADS)

    Ramachandran, Prakash; Alex, Zachariah C.; Nelleri, Anith

    2015-04-01

    Compressive sensing (CS) in digital holography requires only very less number of pixel level detections in hologram plane for accurate image reconstruction and this is achieved by exploiting the sparsity of the object wave. When the input object fields are non-sparse in spatial domain, CS demands a suitable sparsification method like wavelet decomposition. The Fresnelet, a suitable wavelet basis for processing Fresnel digital holograms is an efficient sparsifier for the complex Fresnel field obtained by the Fresnel transform of the object field and minimizes the mutual coherence between sensing and sparsifying matrices involved in CS. The paper demonstrates the merits of Fresnelet based sparsification in compressive digital Fresnel holography over conventional method of sparsifying the input object field. The phase shifting digital Fresnel holography (PSDH) is used to retrieve the complex Fresnel field for the chosen problem. The results are presented from a numerical experiment to show the proof of the concept.

  2. Pit Distribution Design for Computer-Generated Waveguide Holography

    NASA Astrophysics Data System (ADS)

    Yagi, Shogo; Imai, Tadayuki; Ueno, Masahiro; Ohtani, Yoshimitsu; Endo, Masahiro; Kurokawa, Yoshiaki; Yoshikawa, Hiroshi; Watanabe, Toshifumi; Fukuda, Makoto

    2008-02-01

    Multilayered waveguide holography (MWH) is one of a number of page-oriented data multiplexing holographies that will be applied to optical data storage and three-dimensional (3D) moving images. While conventional volumetric holography using photopolymer or photorefractive materials requires page-by-page light exposure for recording, MWH media can be made by employing stamping and laminating technologies that are suitable for mass production. This makes devising an economical mastering technique for replicating holograms a key issue. In this paper, we discuss an approach to pit distribution design that enables us to replace expensive electron beam mastering with economical laser beam mastering. We propose an algorithm that avoids the overlapping of even comparatively large adjacent pits when we employ laser beam mastering. We also compensate for the angular dependence of the diffraction power, which strongly depends on pit shape, by introducing an enhancement profile so that a diffracted image has uniform intensity.

  3. OTF and PSF of circular-grating optical scanning holography

    NASA Astrophysics Data System (ADS)

    Liang, Wanguo; Zhao, Dazun; Xie, Jinghui; Zhao, Yeling

    1998-08-01

    The recording of the hologram in the optical scanning holography (OSH) proposed by T.C. Poon is a process in which a Fresnel zone plate (FZP) is used to scan the object, but since the spacing between two adjacent rings of FZP at the center portion is greater than that at the edge portion, the resolution capability of the system, which can resolve the edge portion of the FZP, is not fully exploited. The fact that a circular grating (CG) has uniform spacings everywhere, enlightens us to suggest the CG optical scanning holography. It has been found that the optical transfer function of the system equals the Fourier transform of the intensity transmissivity of the projecting circular grating, and the point spread function of the system equals to a (delta) function. Also given in this paper are the principles of the CG optical scanning holography and the computer simulations.

  4. Near-field electromagnetic holography for high-resolution analysis of network interactions in neuronal tissue

    PubMed Central

    Kjeldsen, Henrik D.; Kaiser, Marcus; Whittington, Miles A.

    2015-01-01

    Background Brain function is dependent upon the concerted, dynamical interactions between a great many neurons distributed over many cortical subregions. Current methods of quantifying such interactions are limited by consideration only of single direct or indirect measures of a subsample of all neuronal population activity. New method Here we present a new derivation of the electromagnetic analogy to near-field acoustic holography allowing high-resolution, vectored estimates of interactions between sources of electromagnetic activity that significantly improves this situation. In vitro voltage potential recordings were used to estimate pseudo-electromagnetic energy flow vector fields, current and energy source densities and energy dissipation in reconstruction planes at depth into the neural tissue parallel to the recording plane of the microelectrode array. Results The properties of the reconstructed near-field estimate allowed both the utilization of super-resolution techniques to increase the imaging resolution beyond that of the microelectrode array, and facilitated a novel approach to estimating causal relationships between activity in neocortical subregions. Comparison with existing methods The holographic nature of the reconstruction method allowed significantly better estimation of the fine spatiotemporal detail of neuronal population activity, compared with interpolation alone, beyond the spatial resolution of the electrode arrays used. Pseudo-energy flow vector mapping was possible with high temporal precision, allowing a near-realtime estimate of causal interaction dynamics. Conclusions Basic near-field electromagnetic holography provides a powerful means to increase spatial resolution from electrode array data with careful choice of spatial filters and distance to reconstruction plane. More detailed approaches may provide the ability to volumetrically reconstruct activity patterns on neuronal tissue, but the ability to extract vectored data with the

  5. Experimental research of CCD/LCD in holography

    NASA Astrophysics Data System (ADS)

    Yin, Na; Li, Lintao; Wang, Hongtao; Guo, Fei; Wang, Wensheng

    2008-03-01

    Holography has been widely applied in industry measurement, especially in 3D non-contact testing. Combining a high resolution charge-coupled device (CCD) with a phase modulating liquid crystal display (LCD), holographic interferogram recording and display could be realized by digital holographic technique. Digital holographic technique has a great number of important and practical applications. In the conventional holography hologram was detected and reconstructed by the holography panchromatic plate, or the photoconductive thermoplastic film, or the BSO crystal and etc. But in the digital holography--the numerical version of the conventional holographic technique, hologram is digitally detected by CCD and then displayed on the computer monitor. By reconstruction, the hologram is writted into LCD, then illuminating the LCD with the reference wave, the tested object may be reconstructed optically. In this paper the application technique of CCD/LCD in holography is theoretically studied and the bottle techniques have been solved. According to the resolving power of the CCD and LCD, the angle between the two interfering waves should be less than 3° for recording the interference fringes with high spatial frequency. The simple and prospective optical architecture is perhaps Twyman-Green interferometer for easy to adjust the required small angle between reference and tested object waves, and also optical path deference for satisfying the requirement of spatial and temporal coherence. The disadvantages of CCD/LCD digital holographic technique is the small separation angle between zero-order and +/-1-order diffraction. In order to separate +/-1-order from zero-order diffraction, the minimum fringe spacing formed by the interference of object wave with reference wave should satisfy the sampling theorem. This decides a relationship between the size of object and the recording distance, which will be discussed in detail in the following text. And also discussion about the

  6. Digital holography with electron wave: measuring into the nanoworld

    NASA Astrophysics Data System (ADS)

    Mendoza Santoyo, Fernando; Voelkl, Edgar

    2016-04-01

    Dennis Gabor invented Holography in 1949. His main concern at the time was centered on the spherical aberration correction in the recently created electron microscopes, especially after O. Scherzer had shown mathematically that round electron optical lenses always have a positive spherical aberration coefficient and the mechanical requirements for minimizing the spherical aberration were too high to allow for atomic resolution. At the time the lack of coherent electron sources meant that in-line holography was developed using quasi-coherent light sources. As such Holography did not produce scientific good enough results to be considered a must use tool. In 1956, G. Moellenstedt invented a device called a wire-biprism that allowed the object and reference beams to be combined in an off-axis configuration. The invention of the laser at the end of the 1950s gave a great leap to Holography since this light source was highly coherent and hence led to the invention of Holographic Interferometry during the first lustrum of the 1960s. This new discipline in the Optics field has successfully evolved to become a trusted tool in a wide variety of areas. Coherent electron sources were made available only by the late 1970s, a fact that gave an outstanding impulse to electron holography so that today nanomaterials and structures belonging to a wide variety of subjects can be characterized in regards to their physical and mechanical parameters. This invited paper will present and discuss electron holography's state of the art applications to study the shape of nanoparticles and bacteria, and the qualitative and quantitative study of magnetic and electric fields produced by novel nano-structures.

  7. m-Learning and holography: Compatible techniques?

    NASA Astrophysics Data System (ADS)

    Calvo, Maria L.

    2014-07-01

    Since the last decades, cell phones have become increasingly popular and are nowadays ubiquitous. New generations of cell phones are now equipped with text messaging, internet, and camera features. They are now making their way into the classroom. This is creating a new teaching and learning technique, the so called m-Learning (or mobile-Learning). Because of the many benefits that cell phones offer, teachers could easily use them as a teaching and learning tool. However, an additional work from the teachers for introducing their students into the m-Learning in the classroom needs to be defined and developed. As an example, optical techniques, based upon interference and diffraction phenomena, such as holography, appear to be convenient topics for m-Learning. They can be approached with simple examples and experiments within the cell phones performances and classroom accessibility. We will present some results carried out at the Faculty of Physical Sciences in UCM to obtain very simple holographic recordings via cell phones. The activities were carried out inside the course on Optical Coherence and Laser, offered to students in the fourth course of the Grade in Physical Sciences. Some open conclusions and proposals will be presented.

  8. Holography And Holometry Applications In Dental Research

    NASA Astrophysics Data System (ADS)

    Willenborg, George C.

    1987-06-01

    The earliest reference to holographic applications appeared in the dental literature in 1972 when Wictorin, Bjelkhagen and Abramson described a method to study elastic deformation of defective gold solder joints in simulated fixed bridges. Their paper, published in the Swedish dental literature, offered a concise presentation of the interferometry technique which led to the development of other research applications of holographic interferometry(holometry) in dentistry. In this presentation, the development and application of the interferometry technique in the dental field will be discussed. Various interesting and potentially useful applications of holography have appeared in the dental literature over the past decade. Some of these, which will be discussed, include the use of holograms as a storage medium for dental study models, multiplexing of computer(CT) scan sections to form white light viewable holograms and the potential application of holographic training aids in the teaching of the basic courses of dental anatomy and restorative dentistry. In addition, some unique related applications will be mentioned including a laser reflection method for accurate non-contact measurement of tooth mobility/movement and a technique for contour mapping of occlusal surfaces to measure wear of restorative materials.

  9. Digital holography system for undergraduate student laboratory

    NASA Astrophysics Data System (ADS)

    Buranasiri, P.; Plaipichit, S.; Yindeesuk, W.; Yoshimori, K.

    2015-07-01

    In this paper, we discuss the digital holography (DH) experiment in our optical and communication laboratory course for undergraduate students at Physics department, KMITL. The purposes of DH experiment are presenting our students the meaning and advantage of DH and its applications. The Gabor configurations of in-line DH has been set up for recording a number of samples, which were placed on different distances, simultaneously. Then, the images of all objects have been numerical reconstructed by using computer. The students have been learned that all of reconstructed images have been got from only one time recording, while using the conventional recording technique, sharp images of different objects have been gotten from different recording time. The students also have been learned how to use DH technique for investigation some different kinds of samples on their own of interested such as a human hair or a fingerprint. In our future work, our DH system will be developed to be a portable apparatus for easily showing to children in different areas.

  10. Synthetic holography based on scanning microcavity

    NASA Astrophysics Data System (ADS)

    Di Donato, A.; Farina, M.

    2015-11-01

    Synthetic optical holography (SOH) is an imaging technique, introduced in scanning microscopy to record amplitude and phase of a scattered field from a sample. In this paper, it is described a novel implementation of SOH through a lens-free low-coherence system, based on a scanning optical microcavity. This technique combines the low-coherence properties of the source with the mutual interference of scattered waves and the resonant behavior of a micro-cavity, in order to realize a high sensitive imaging system. Micro-cavity is compact and realized by approaching a cleaved optical fiber to the sample. The scanning system works in an open-loop configuration without the need for a reference wave, usually required in interferometric systems. Measurements were performed over calibration samples and a lateral resolution of about 1 μm is achieved by means of an optical fiber with a Numerical Aperture (NA) equal to 0.1 and a Mode Field Diameter (MDF) of 5.6 μm.

  11. Effective actions for relativistic fluids from holography

    NASA Astrophysics Data System (ADS)

    de Boer, Jan; Heller, Michal P.; Pinzani-Fokeeva, Natalia

    2015-08-01

    Motivated by recent progress in developing action formulations of relativistic hydrodynamics, we use holography to derive the low energy dissipationless effective action for strongly coupled conformal fluids. Our analysis is based on the study of novel double Dirichlet problems for the gravitational field, in which the boundary conditions are set on two codimension one timelike hypersurfaces (branes). We provide a geometric interpretation of the Goldstone bosons appearing in such constructions in terms of a family of spatial geodesics extending between the ultraviolet and the infrared brane. Furthermore, we discuss supplementing double Dirichlet problems with information about the near-horizon geometry. We show that upon coupling to a membrane paradigm boundary condition, our approach reproduces correctly the complex dispersion relation for both sound and shear waves. We also demonstrate that upon a Wick rotation, our formulation reproduces the equilibrium partition function formalism, provided the near- horizon geometry is properly accounted for. Finally, we define the conserved hydrodynamic entropy current as the Noether current associated with a particular transformation of the Goldstone bosons.

  12. NAH plasmid-mediated catabolism of anthracene and phenanthrene to naphthoic acids.

    PubMed Central

    Menn, F M; Applegate, B M; Sayler, G S

    1993-01-01

    Pseudomonas fluorescens 5R contains an NAH7-like plasmid (pKA1), and P. fluorescens 5R mutant 5RL contains a bioluminescent reporter plasmid (pUTK21) which was constructed by transposon mutagenesis. Polymerase chain reaction mapping confirmed the localization of lux transposon Tn4431 300 bp downstream from the start of the nahG gene. Two degradation products, 2-hydroxy-3-naphthoic acid and 1-hydroxy-2-naphthoic acid, were recovered and identified from P. fluorescens 5RL as biochemical metabolites from the biotransformation of anthracene and phenanthrene, respectively. This is the first report which provides direct biochemical evidence that the naphthalene plasmid degradative enzyme system is involved in the degradation of higher-molecular-weight polycyclic aromatic hydrocarbons other than naphthalene. Images PMID:8328810

  13. High Temperature Measurements Of Martensitic transformations Using Digital Holography

    SciTech Connect

    Thiesing, Benjamin; Mann, Christopher J; Dryepondt, Sebastien N

    2013-01-01

    During thermal cycling of nickel-aluminum-platinum (NiAlPt) and single crystal Fe-15Cr-15Ni alloys, the structural changes associated with the martensite to austenite phase transformation were measured using dual-wavelength digital holography. Real-time in-situ measurements reveal the formation of striations within the NiPtAl alloy at 70 C and the FeCrNi alloy at 520 C. The results demonstrate that digital holography is an effective technique for acquiring non-contact, high precision information of the surface evolution of alloys at high temperatures.

  14. Second-harmonic radiating imaging probes and harmonic holography

    NASA Astrophysics Data System (ADS)

    Pu, Ye; Psaltis, Demetri

    2016-10-01

    Compared with other imaging probes such as fluorescent dyes and quantum dots, second-harmonic radiating imaging probes (SHRIMPs) provide a unique ultrafast, coherent optical contrast that is free of photobleaching and emission intermittency. Using the second-harmonic signal emitted from SHRIMPs, harmonic holography achieves threedimensional holographic imaging with a color contrast similar to fluorescence microscopy where the uninterested background scattering is efficiently suppressed by an optical filter. The coherent contrast provided by SHRIMPs also enables imaging through turbid media via digital phase conjugation. Here we review the developments and applications of SHRIMPs and harmonic holography.

  15. Two-step-only quadrature phase-shifting digital holography.

    PubMed

    Liu, Jung-Ping; Poon, Ting-Chung

    2009-02-01

    Conventional methods of quadrature phase-shifting holography require two holograms and either intensity distribution of the reference wave or that of the object wave to reconstruct an original object without the zero order and the twin-image noise in an on-axis holographic recording setup. We present a technique called two-step-only quadrature phase-shifting holography in which solely two quadrature-phase holograms are required. Neither reference-wave intensity nor an object-wave intensity measurement is needed in the technique.

  16. Holography and the virtual patient: the holographic medical image

    NASA Astrophysics Data System (ADS)

    Ko, Kathryn; Erickson, Ronald R.; Webster, John M.

    1996-12-01

    Practical holographic systems utilizing the pulsed laser are finding potential applications in medicine. Exploiting both the hologram's true 3D image and holographic interferometry these techniques enhance the physician's vision beyond the 2D radiological imaging of even the best CT and MRI. The authors describe the use of pulsed laser holography as applied to the morphological specialties: anatomy, pathology, and surgery. The authors report on the Holographic Brain Anatomy Atlas for medical education; pathologic documentation with holography, and the use of holographic interferometry in surgical planning. The techniques are outlined and a discussion on the interpretation of holographic interferometry with living subjects is provided.

  17. High temperature measurements of martensitic transformations using digital holography.

    PubMed

    Thiesing, Benjamin P; Mann, Christopher J; Dryepondt, Sebastien

    2013-07-01

    During thermal cycling of nickel-aluminum-platinum (NiAlPt) and single crystal iron-chromium-nickel (FeCrNi) alloys, the structural changes associated with the martensite to austenite phase transformation were measured using dual-wavelength digital holography. Real-time in situ measurements reveal the formation of striations within the NiAlPt alloy at 70°C and the FeCrNi alloy at 520°C. The results demonstrate that digital holography is an effective technique for acquiring noncontact, high precision information of the surface evolution of alloys at high temperatures.

  18. Continuous-wave terahertz reflective off-axis digital holography

    NASA Astrophysics Data System (ADS)

    Wan, Min; Wang, Dayong; Rong, Lu; Wang, Yunxin; Huang, Haochong; Li, Bin

    2016-10-01

    Terahertz (THz) continuous-wave digital holography is an advanced interference imaging technique that can reconstruct quantitative distributions of amplitude and phase of the sample in real time with high resolution. In this paper, a reflective off-axis holographic system is presented. A Gaussian fitting method is applied to enhance the hologram contrast and Laplacian of Gaussian filter is used to obtain the reconstructed distance automatically. Furthermore, spectrum filtering method and angular spectrum algorithm are used to obtain the complex amplitude of the one-yuan chinese metal coin. The results confirm the prospective application of terahertz digital holography in the surface morphology for reflective samples.

  19. Na+/H+ exchanger 1 inhibition reverses manifestation of peripheral diabetic neuropathy in type 1 diabetic rats

    PubMed Central

    Lupachyk, Sergey; Watcho, Pierre; Shevalye, Hanna; Vareniuk, Igor; Obrosov, Alexander; Obrosova, Irina G.

    2013-01-01

    Evidence for an important role for Na+/H+ exchangers in diabetic complications is emerging. The aim of this study was to evaluate whether Na+/H+ exchanger 1 inhibition reverses experimental peripheral diabetic neuropathy. Control and streptozotocin-diabetic rats were treated with the specific Na+/H+ exchanger 1 inhibitor cariporide for 4 wk after 12 wk without treatment. Neuropathy end points included sciatic motor and sensory nerve conduction velocities, endoneurial nutritive blood flow, vascular reactivity of epineurial arterioles, thermal nociception, tactile allodynia, and intraepidermal nerve fiber density. Advanced glycation end product and markers of oxidative stress, including nitrated protein levels in sciatic nerve, were evaluated by Western blot. Rats with 12-wk duration of diabetes developed motor and sensory nerve conduction deficits, thermal hypoalgesia, tactile allodynia, and intraepidermal nerve fiber loss. All these changes, including impairment of nerve blood flow and vascular reactivity of epineurial arterioles, were partially reversed by 4 wk of cariporide treatment. Na+/H+ exchanger 1 inhibition was also associated with reduction of diabetes-induced accumulation of advanced glycation endproduct, oxidative stress, and nitrated proteins in sciatic nerve. In conclusion, these findings support an important role for Na+/H+ exchanger 1 in functional, structural, and biochemical manifestations of peripheral diabetic neuropathy and provide the rationale for development of Na+/H+ exchanger 1 inhibitors for treatment of diabetic vascular and neural complications. PMID:23736542

  20. Functional analysis of amino acids of the Na+/H+ exchanger that are important for proton translocation.

    PubMed

    Wiebe, Christine A; Rieder, Carmen; Young, Paul G; Dibrov, Pavel; Fliegel, Larry

    2003-12-01

    The Na+/H+ exchanger is an integral membrane protein found in the plasma membrane of eukaryotic and prokaryotic cells. In eukaryotes it functions to exchange one proton for a sodium ion. In mammals it removes intracellular protons while in plants and fungal cells the plasma membrane form removes intracellular sodium in exchange for extracellular protons. In this study we used the Na+/H+ exchanger of Schizosaccharomyces pombe (Sod2) as a model system to study amino acids critical for activity of the protein. Twelve mutant forms of the Na+/H+ exchanger were examined for their ability to translocate protons as assessed by a Cytosensor microphysiometer. Mutation of the amino acid Histidine 367 resulted in defective proton translocation. The acidic residues Asp145, Asp178, Asp266 and Asp267 were important in the proton translocation activity of the Na+/H+ exchanger. Mutation of amino acids His98, His233 and Asp241 did not significantly impair proton translocation by the Na+/H+ exchanger. These results confirm that polar amino acids are important in proton flux activity of Na+/H+ exchangers.

  1. A novel plant vacuolar Na+/H+ antiporter gene evolved by DNA shuffling confers improved salt tolerance in yeast.

    PubMed

    Xu, Kai; Zhang, Hui; Blumwald, Eduardo; Xia, Tao

    2010-07-23

    Plant vacuolar Na(+)/H(+) antiporters play important roles in maintaining cellular ion homeostasis and mediating the transport of Na(+) out of the cytosol and into the vacuole. Vacuolar antiporters have been shown to play significant roles in salt tolerance; however the relatively low V(max) of the Na(+)/H(+) exchange of the Na(+)/H(+) antiporters identified could limit its application in the molecular breeding of salt tolerant crops. In this study, we applied DNA shuffling methodology to generate and recombine the mutations of Arabidopsis thaliana vacuolar Na(+)/H(+) antiporter gene AtNHX1. Screening using a large scale yeast complementation system identified AtNHXS1, a novel Na(+)/H(+) antiporter. Expression of AtNHXS1 in yeast showed that the antiporter localized to the vacuolar membrane and that its expression improved the tolerance of yeast to NaCl, KCl, LiCl, and hygromycin B. Measurements of the ion transport activity across the intact yeast vacuole demonstrated that the AtNHXS1 protein showed higher Na(+)/H(+) exchange activity and a slightly improved K(+)/H(+) exchange activity.

  2. Effects of electron doping on the stability of the metal hydride NaH

    NASA Astrophysics Data System (ADS)

    Olea-Amezcua, M. A.; Rivas-Silva, J. F.; de la Peña-Seaman, O.; Heid, R.; Bohnen, K. P.

    2017-04-01

    Alkali and alkali-earth metal hydrides have high volumetric and gravimetric hydrogen densities, but due to their high thermodynamic stability, they possess high dehydrogenation temperatures which may be reduced by transforming these compounds into less stable states/configurations. We present a systematic computational study of the electron doping effects on the stability of the alkali metal hydride NaH substituted with Mg, using the self-consistent version of the virtual crystal approximation to model the alloy Na1‑x Mg x H. The phonon dispersions were studied paying special attention to the crystal stability and the correlations with the electronic structure taking into account the zero point energy contribution. We found that substitution of Na by Mg in the hydride invokes a reduction of the frequencies, leading to dynamical instabilities for Mg content of 25%. The microscopic origin of these instabilities could be related to the formation of ellipsoidal Fermi surfaces centered at the L point due to the metallization of the hydride by the Mg substitution. Applying the quasiharmonic approximation, thermodynamic properties like heat capacities, vibrational entropies and vibrational free energies as a function of temperature at zero pressure are obtained. These properties determine an upper temperature for the thermodynamic stability of the hydride, which decreases from 600 K for NaH to 300 K at 20% Mg concentration. This significant reduction of the stability range indicates that dehydrogenation could be favoured by electron doping of NaH.

  3. Functional expression of the Schizosaccharomyces pombe Na+/H+ antiporter gene, sod2, in Saccharomyces cerevisiae.

    PubMed Central

    Hahnenberger, K M; Jia, Z; Young, P G

    1996-01-01

    In the fission yeast, Schizosaccharomyces pombe, tolerance to high sodium and lithium concentrations requires the functioning of the sod2, Na+/H+ antiporter. We have directly measured the activity of this antiporter and demonstrated reconstitution of the activity in gene deletion strains. In addition, we have shown that it can be transferred to, and its antiporter activity detected in, the budding yeast, Saccharomyces cerevisiae, where it also confers sodium and lithium tolerance. Proton flux through the S. pombe Na+/H+ antiporter was directly measured using microphysiometry. The direction of transmembrane proton flux mediated by this antiporter was reversible, with protons being imported or exported in response to the external concentration of sodium. This bidirectional activity was also detected in S. cerevisiae strains expressing sod2 and expression of this gene complemented the sodium and lithium sensitivity resulting from inactivation of the ENA1/PMR2 encoded Na+-exporting ATPases. This suggests that antiporters or sodium pumps can be utilized interchangeably by S. cerevisiae to regulate internal sodium concentration. Potent inhibitors of mammalian Na+/H+ exchangers were found to have no effect on sod2 activity. The proton flux mediated by sod2 was also found to be unaffected by perturbation of membrane potential or the plasma membrane proton gradient. PMID:8643524

  4. Monitoring of naphthalene catabolism by bioluminescence with nah-lux transcriptional fusions.

    PubMed Central

    Burlage, R S; Sayler, G S; Larimer, F

    1990-01-01

    We have demonstrated the efficacy of a light-generating genetic construction in describing the induction of a nah operon for the catabolism of naphthalene. A fragment from plasmid NAH7, which contains the promoter for the upper pathway of degradation, was transcriptionally fused to the lux genes of Vibrio fischeri. A Pseudomonas strain containing this construction is inducible to high levels of light production in the presence of a suitable substrate and the nahR regulatory gene product. This system was used to examine catabolic activity in a unique manner under a variety of growth conditions. Induction of bioluminescence was demonstrated to coincide with naphthalene degradation in all cases through the use of mineralization assays. A significant delay in bioluminescence and biodegradation was observed when naphthalene was added to batch cultures that were growing exponentially. These results suggest that the metabolism of naphthalene by this Pseudomonas strain is optimal when the growth rate of the culture is slow and is greatly reduced during exponential growth. Images PMID:2203729

  5. Effects of electron doping on the stability of the metal hydride NaH.

    PubMed

    Olea-Amezcua, M A; Rivas-Silva, J F; de la Peña-Seaman, O; Heid, R; Bohnen, K P

    2017-04-12

    Alkali and alkali-earth metal hydrides have high volumetric and gravimetric hydrogen densities, but due to their high thermodynamic stability, they possess high dehydrogenation temperatures which may be reduced by transforming these compounds into less stable states/configurations. We present a systematic computational study of the electron doping effects on the stability of the alkali metal hydride NaH substituted with Mg, using the self-consistent version of the virtual crystal approximation to model the alloy Na1-x Mg x H. The phonon dispersions were studied paying special attention to the crystal stability and the correlations with the electronic structure taking into account the zero point energy contribution. We found that substitution of Na by Mg in the hydride invokes a reduction of the frequencies, leading to dynamical instabilities for Mg content of 25%. The microscopic origin of these instabilities could be related to the formation of ellipsoidal Fermi surfaces centered at the L point due to the metallization of the hydride by the Mg substitution. Applying the quasiharmonic approximation, thermodynamic properties like heat capacities, vibrational entropies and vibrational free energies as a function of temperature at zero pressure are obtained. These properties determine an upper temperature for the thermodynamic stability of the hydride, which decreases from 600 K for NaH to 300 K at 20% Mg concentration. This significant reduction of the stability range indicates that dehydrogenation could be favoured by electron doping of NaH.

  6. Volumetric Acoustic Vector Intensity Probe

    NASA Technical Reports Server (NTRS)

    Klos, Jacob

    2006-01-01

    A new measurement tool capable of imaging the acoustic intensity vector throughout a large volume is discussed. This tool consists of an array of fifty microphones that form a spherical surface of radius 0.2m. A simultaneous measurement of the pressure field across all the microphones provides time-domain near-field holograms. Near-field acoustical holography is used to convert the measured pressure into a volumetric vector intensity field as a function of frequency on a grid of points ranging from the center of the spherical surface to a radius of 0.4m. The volumetric intensity is displayed on three-dimensional plots that are used to locate noise sources outside the volume. There is no restriction on the type of noise source that can be studied. The sphere is mobile and can be moved from location to location to hunt for unidentified noise sources. An experiment inside a Boeing 757 aircraft in flight successfully tested the ability of the array to locate low-noise-excited sources on the fuselage. Reference transducers located on suspected noise source locations can also be used to increase the ability of this device to separate and identify multiple noise sources at a given frequency by using the theory of partial field decomposition. The frequency range of operation is 0 to 1400Hz. This device is ideal for the study of noise sources in commercial and military transportation vehicles in air, on land and underwater.

  7. Imaging of Acoustic Waves in Sand

    SciTech Connect

    Deason, Vance Albert; Telschow, Kenneth Louis; Watson, Scott Marshall

    2003-08-01

    There is considerable interest in detecting objects such as landmines shallowly buried in loose earth or sand. Various techniques involving microwave, acoustic, thermal and magnetic sensors have been used to detect such objects. Acoustic and microwave sensors have shown promise, especially if used together. In most cases, the sensor package is scanned over an area to eventually build up an image or map of anomalies. We are proposing an alternate, acoustic method that directly provides an image of acoustic waves in sand or soil, and their interaction with buried objects. The INEEL Laser Ultrasonic Camera utilizes dynamic holography within photorefractive recording materials. This permits one to image and demodulate acoustic waves on surfaces in real time, without scanning. A video image is produced where intensity is directly and linearly proportional to surface motion. Both specular and diffusely reflecting surfaces can be accomodated and surface motion as small as 0.1 nm can be quantitatively detected. This system was used to directly image acoustic surface waves in sand as well as in solid objects. Waves as frequencies of 16 kHz were generated using modified acoustic speakers. These waves were directed through sand toward partially buried objects. The sand container was not on a vibration isolation table, but sat on the lab floor. Interaction of wavefronts with buried objects showed reflection, diffraction and interference effects that could provide clues to location and characteristics of buried objects. Although results are preliminary, success in this effort suggests that this method could be applied to detection of buried landmines or other near-surface items such as pipes and tanks.

  8. Intellectual property issues in holography and high tech

    NASA Astrophysics Data System (ADS)

    Reingand, Nadya

    2004-06-01

    The author with technical education background (Ph.D. in holography) shares her 3+ years of experience working on intellectual property (IP) issues that includes patents, trademarks, and copyrights. A special attention is paid to the patent issues: the application procedure, the patent requirements, the databases for prior art search, how to make the cost efficient filing.

  9. Digital holography and 3D imaging: introduction to feature issue.

    PubMed

    Kim, Myung K; Hayasaki, Yoshio; Picart, Pascal; Rosen, Joseph

    2013-01-01

    This feature issue of Applied Optics on Digital Holography and 3D Imaging is the sixth of an approximately annual series. Forty-seven papers are presented, covering a wide range of topics in phase-shifting methods, low coherence methods, particle analysis, biomedical imaging, computer-generated holograms, integral imaging, and many others.

  10. Calendar effects in quantum mechanics in view of interactive holography

    NASA Astrophysics Data System (ADS)

    Berkovich, Simon

    2013-04-01

    Quantum mechanics in terms of interactive holography appears as `normal' science [1]. With the holography quantum behavior is determined by the interplay of material formations and their conjugate images. To begin with, this effortlessly elucidates the nonlocality in quantum entanglements. Then, it has been shown that Schr"odinger's dynamics for a single particle arises from Bi-Fragmental random walks of the particle itself and its holographic image. For many particles this picture blurs with fragments merging as bosons or fermions. In biomolecules, swapping of particles and their holographic placeholders leads to self-replication of the living matter. Because of broad interpretations of quantum formalism direct experiments attributing it to holography may not be very compelling. The holographic mechanism better reveals as an absolute frame of reference. A number of physical and biological events exhibit annual variations when Earth orbital position changes with respect to the universal holographic mechanism. The well established calendar variations of heart attacks can be regarded as a positive outcome of a generalization of the Michelson experiment, where holography is interferometry and ailing hearts are detectors of pathologically replicated proteins. Also, there have been already observed calendar changes in radioactive decay rates. The same could be expected for various fine quantum experiences, like, e.g., Josephson tunneling. In other words, Quantum Mechanics (February) Quantum Mechanics (August). [1] S. Berkovich, ``A comprehensive explanation of quantum mechanics,'' www.cs.gwu.edu/research/technical-report/170 .

  11. Applications of holography. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Carrigan, B.

    1980-05-01

    The bibliography covers studies on the applications of holography in such areas as photograping high-speed particles, nondestructive testing of material defects, strain analysis, microscopy, interferometry, vibration measurement, and medical diagnosis. This updated bibliography contains 249 abstracts, none of which are new entries to the previous edition.

  12. Applications of holography. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Carrigan, B.

    1980-05-01

    The bibliography covers studies on the applications of holography in such areas as photographing high-speed particles, nondestructive testing of material defects, strain analysis, microscopy, interferometry, vibration measurement, and medical diagnosis. This updated bibliography contains 59 abstracts, 42 of which are new entries to the previous edition.

  13. Three-dimensional microscopy by optical scanning holography

    NASA Astrophysics Data System (ADS)

    Poon, Ting-Chung; Doh, Kyu B.; Schilling, Bradley W.; Wu, Ming H.; Shinoda, Kazunori K.; Suzuki, Yoshiji

    1995-05-01

    We first briefly review a new 3D imaging technique called optical scanning holography (OSH). We then discuss the technique's 3D holographic magnification in the context of optical scanning and digital reconstruction. Finally, we demonstrate the 3D imaging capability of OSH by holographically recording two planar objects at different depths and reconstructing the hologram digitally.

  14. Conoscopic holography for image registration: a feasibility study

    NASA Astrophysics Data System (ADS)

    Lathrop, Ray A.; Cheng, Tiffany T.; Webster, Robert J., III

    2009-02-01

    Preoperative image data can facilitate intrasurgical guidance by revealing interior features of opaque tissues, provided image data can be accurately registered to the physical patient. Registration is challenging in organs that are deformable and lack features suitable for use as alignment fiducials (e.g. liver, kidneys, etc.). However, provided intraoperative sensing of surface contours can be accomplished, a variety of rigid and deformable 3D surface registration techniques become applicable. In this paper, we evaluate the feasibility of conoscopic holography as a new method to sense organ surface shape. We also describe potential advantages of conoscopic holography, including the promise of replacing open surgery with a laparoscopic approach. Our feasibility study investigated use of a tracked off-the-shelf conoscopic holography unit to perform a surface scans on several types of biological and synthetic phantom tissues. After first exploring baseline accuracy and repeatability of distance measurements, we performed a number of surface scan experiments on the phantom and ex vivo tissues with a variety of surface properties and shapes. These indicate that conoscopic holography is capable of generating surface point clouds of at least comparable (and perhaps eventually improved) accuracy in comparison to published experimental laser triangulation-based surface scanning results.

  15. Dopant profiling in the TEM, progress towards quantitative electron holography

    SciTech Connect

    Cooper, David; Truche, Robert; Chabli, Amal; Twitchett-Harrison, Alison C.; Midgley, Paul A.; Dunin-Borkowski, Rafal E.

    2007-09-26

    Off-axis electron holography has been used to characterise the dopant potential in GaAs p-n junctions. We show that the measured potential across the junctions is affected by both FIB specimen preparation and by charging in the TEM and suggest methods that can be used to minimise these problems.

  16. Musical Acoustics

    NASA Astrophysics Data System (ADS)

    Gough, Colin

    This chapter provides an introduction to the physical and psycho-acoustic principles underlying the production and perception of the sounds of musical instruments. The first section introduces generic aspects of musical acoustics and the perception of musical sounds, followed by separate sections on string, wind and percussion instruments.

  17. Parallel optical-path-length-shifting digital holography.

    PubMed

    Awatsuji, Yasuhiro; Koyama, Takamasa; Tahara, Tatsuki; Ito, Kenichi; Shimozato, Yuki; Kaneko, Atsushi; Nishio, Kenzo; Ura, Shogo; Kubota, Toshihiro; Matoba, Osamu

    2009-12-01

    The authors propose an optical-path-length-shifting digital holography as a technique capable of single-shot recording of three-dimensional information of objects. With a single image sensor, the proposed technique can simultaneously record all of the holograms required for the in-line digital holography that reconstruct the image of an object from two intensity measurements at different planes. The technique can be optically implemented by using an optical-path-length-shifting array device located in the common path of the reference and object waves. The array device has periodic structure of two-step optical-path difference. The configuration of the array device of the proposed technique is simpler than the phase-shifting array device required for parallel phase-shifting digital holographies. Therefore, the optical system of the proposed technique is more suitable for the realization of a single-shot in-line digital holography system that removes the conjugate image from the reconstructed image. The authors conducted both a numerical simulation and a preliminary experiment of the proposed technique. The reconstructed images were quantitatively evaluated by using root mean squared error. In comparison to single-shot digital holography using the Fresnel transform alone, with the proposed technique the root mean squared errors of the technique were reduced to less than 1/6 in amplitude and 1/3 in phase. Also the results of the simulation and experiment agreed well with the images of an object. Thus the effectiveness of the proposed technique is verified.

  18. Some Remarks on the Historical Origin and Current Prospects of Holography

    NASA Astrophysics Data System (ADS)

    Sieroka, Norman

    2015-01-01

    Holography is sometimes claimed to be a fundamental principle in the advancement of quantum gravity. This paper critically evaluates this claim and provides a look back at an important historical forerunner of the modern concept of holography, which is to be found in the work of Hermann Weyl. By the same token, a brief and rather skeptical response to the recent and broad public interest in holography will be given.

  19. Optical holography applications for the zero-g Atmospheric Cloud Physics Laboratory

    NASA Technical Reports Server (NTRS)

    Kurtz, R. L.

    1974-01-01

    A complete description of holography is provided, both for the time-dependent case of moving scene holography and for the time-independent case of stationary holography. Further, a specific holographic arrangement for application to the detection of particle size distribution in an atmospheric simulation cloud chamber. In this chamber particle growth rate is investigated; therefore, the proposed holographic system must capture continuous particle motion in real time. Such a system is described.

  20. QCD and Light-Front Holography

    SciTech Connect

    Brodsky, Stanley J.; de Teramond, Guy F.; /Costa Rica U.

    2010-10-27

    The soft-wall AdS/QCD model, modified by a positive-sign dilaton metric, leads to a remarkable one-parameter description of nonperturbative hadron dynamics. The model predicts a zero-mass pion for zero-mass quarks and a Regge spectrum of linear trajectories with the same slope in the leading orbital angular momentum L of hadrons and the radial quantum number N. Light-Front Holography maps the amplitudes which are functions of the fifth dimension variable z of anti-de Sitter space to a corresponding hadron theory quantized on the light front. The resulting Lorentz-invariant relativistic light-front wave equations are functions of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron at equal light-front time. The result is to a semi-classical frame-independent first approximation to the spectra and light-front wavefunctions of meson and baryon light-quark bound states, which in turn predict the behavior of the pion and nucleon form factors. The theory implements chiral symmetry in a novel way: the effects of chiral symmetry breaking increase as one goes toward large interquark separation, consistent with spectroscopic data, and the the hadron eigenstates generally have components with different orbital angular momentum; e.g., the proton eigenstate in AdS/QCD with massless quarks has L = 0 and L = 1 light-front Fock components with equal probability. The soft-wall model also predicts the form of the non-perturbative effective coupling {alpha}{sub s}{sup AdS} (Q) and its {beta}-function which agrees with the effective coupling {alpha}{sub g1} extracted from the Bjorken sum rule. The AdS/QCD model can be systematically improved by using its complete orthonormal solutions to diagonalize the full QCD light-front Hamiltonian or by applying the Lippmann-Schwinger method in order to systematically include the QCD interaction terms. A new perspective on quark and gluon condensates is also reviewed.

  1. NaHS Protects Cochlear Hair Cells from Gentamicin-Induced Ototoxicity by Inhibiting the Mitochondrial Apoptosis Pathway

    PubMed Central

    Dong, Yaodong; Liu, Dongliang; Hu, Yue; Ma, Xiulan

    2015-01-01

    Aminoglycoside antibiotics such as gentamicin could cause ototoxicity in mammalians, by inducing oxidative stress and apoptosis in sensory hair cells of the cochlea. Sodium hydrosulfide (NaHS) is reported to alleviate oxidative stress and apoptosis, but its role in protecting aminoglycoside-induced hearing loss is unclear. In this study, we investigated the anti-oxidant and anti-apoptosis effect of NaHS in in vitro cultured House Ear Institute-Organ of Corti 1 (HEI-OC1) cells and isolated mouse cochlea. Results from cultured HEI-OC1 cells and cochlea consistently indicated that NaHS exhibited protective effects from gentamicin-induced ototoxicity, evident by maintained cell viability, hair cell number and cochlear morphology, reduced reactive oxygen species production and mitochondrial depolarization, as well as apoptosis activation of the intrinsic pathway. Moreover, in the isolated cochlear culture, NaHS was also demonstrated to protect the explant from gentamicin-induced mechanotransduction loss. Our study using multiple in vitro models revealed for the first time, the potential of NaHS as a therapeutic agent in protecting against aminoglycoside-induced hearing loss. PMID:26295804

  2. NaHS Protects against the Impairments Induced by Oxygen-Glucose Deprivation in Different Ages of Primary Hippocampal Neurons

    PubMed Central

    Yu, Qian; Wang, Binrong; Zhao, Tianzhi; Zhang, Xiangnan; Tao, Lei; Shi, Jinshan; Sun, Xude; Ding, Qian

    2017-01-01

    Brain ischemia leads to poor oxygen supply, and is one of the leading causes of brain damage and/or death. Neuroprotective agents are thus in great need for treatment purpose. Using both young and aged primary cultured hippocampal neurons as in vitro models, we investigated the effect of sodium hydrosulfide (NaHS), an exogenous donor of hydrogen sulfide, on oxygen-glucose deprivation (OGD) damaged neurons that mimick focal cerebral ischemia/reperfusion (I/R) induced brain injury. NaHS treatment (250 μM) protected both young and aged hippocampal neurons, as indicated by restoring number of primary dendrites by 43.9 and 68.7%, number of dendritic end tips by 59.8 and 101.1%, neurite length by 36.8 and 66.7%, and spine density by 38.0 and 58.5% in the OGD-damaged young and aged neurons, respectively. NaHS treatment inhibited growth-associated protein 43 downregulation, oxidative stress in both young and aged hippocampal neurons following OGD damage. Further studies revealed that NaHS treatment could restore ERK1/2 activation, which was inhibited by OGD-induced protein phosphatase 2 (PP2A) upregulation. Our results demonstrated that NaHS has potent protective effects against neuron injury induced by OGD in both young and aged hippocampal neurons. PMID:28326019

  3. Phosphoinositide binding differentially regulates NHE1 Na+/H+ exchanger-dependent proximal tubule cell survival.

    PubMed

    Abu Jawdeh, Bassam G; Khan, Shenaz; Deschênes, Isabelle; Hoshi, Malcolm; Goel, Monu; Lock, Jeffrey T; Shinlapawittayatorn, Krekwit; Babcock, Gerald; Lakhe-Reddy, Sujata; DeCaro, Garren; Yadav, Satya P; Mohan, Maradumane L; Naga Prasad, Sathyamangla V; Schilling, William P; Ficker, Eckhard; Schelling, Jeffrey R

    2011-12-09

    Tubular atrophy predicts chronic kidney disease progression, and is caused by proximal tubular epithelial cellcaused by proximal tubular epithelial cell (PTC) apoptosis. The normally quiescent Na(+)/H(+) exchanger-1 (NHE1) defends against PTC apoptosis, and is regulated by PI(4,5)P(2) binding. Because of the vast array of plasma membrane lipids, we hypothesized that NHE1-mediated cell survival is dynamically regulated by multiple anionic inner leaflet phospholipids. In membrane overlay and surface plasmon resonance assays, the NHE1 C terminus bound phospholipids with low affinity and according to valence (PIP(3) > PIP(2) > PIP = PA > PS). NHE1-phosphoinositide binding was enhanced by acidic pH, and abolished by NHE1 Arg/Lys to Ala mutations within two juxtamembrane domains, consistent with electrostatic interactions. PI(4,5)P(2)-incorporated vesicles were distributed to apical and lateral PTC domains, increased NHE1-regulated Na(+)/H(+) exchange, and blunted apoptosis, whereas NHE1 activity was decreased in cells enriched with PI(3,4,5)P(3), which localized to basolateral membranes. Divergent PI(4,5)P(2) and PI(3,4,5)P(3) effects on NHE1-dependent Na(+)/H(+) exchange and apoptosis were confirmed by selective phosphoinositide sequestration with pleckstrin homology domain-containing phospholipase Cδ and Akt peptides, PI 3-kinase, and Akt inhibition in wild-type and NHE1-null PTCs. The results reveal an on-off switch model, whereby NHE1 toggles between weak interactions with PI(4,5)P(2) and PI(3,4,5)P(3). In response to apoptotic stress, NHE1 is stimulated by PI(4,5)P(2), which leads to PI 3-kinase activation, and PI(4,5)P(2) phosphorylation. The resulting PI(3,4,5)P(3) dually stimulates sustained, downstream Akt survival signaling, and dampens NHE1 activity through competitive inhibition and depletion of PI(4,5)P(2).

  4. Fructose stimulates Na/H exchange activity and sensitizes the proximal tubule to angiotensin II.

    PubMed

    Cabral, Pablo D; Hong, Nancy J; Hye Khan, Md Abdul; Ortiz, Pablo A; Beierwaltes, William H; Imig, John D; Garvin, Jeffrey L

    2014-03-01

    The proximal nephron reabsorbs 60% to 70% of the fluid and sodium and most of the filtered bicarbonate via Na/H exchanger 3. Enhanced proximal nephron transport is implicated in hypertension. Our findings show that a fructose-enriched diet causes salt sensitivity. We hypothesized that fructose stimulates luminal Na/H exchange activity and sensitizes the proximal tubule to angiotensin II. Na/H exchange was measured in rat proximal tubules as the rate of intracellular pH (pHi) recovery in fluorescent units/s. Replacing 5 mmol/L glucose with 5 mmol/L fructose increased the rate of pHi recovery (1.8±0.6 fluorescent units/s; P<0.02; n=8). Staurosporine, a protein kinase C inhibitor, blocked this effect. We studied whether this effect was because of the addition of fructose or removal of glucose. The basal rate of pHi recovery was first tested in the presence of a 0.6-mmol/L glucose and 1, 3, or 5 mmol/L fructose added in a second period. The rate of pHi recovery did not change with 1 mmol/L but it increased with 3 and 5 mmol/L of fructose. Adding 5 mmol/L glucose caused no change. Removal of luminal sodium blocked pHi recovery. With 5.5 mmol/L glucose, angiotensin II (1 pmol/L) did not affect the rate of pHi recovery (change, -1.1±0.5 fluorescent units/s; n=9) but it increased the rate of pHi recovery with 0.6 mmol/L glucose/5 mmol/L fructose (change, 4.0±2.2 fluorescent units/s; P<0.02; n=6). We conclude that fructose stimulates Na/H exchange activity and sensitizes the proximal tubule to angiotensin II. This mechanism is likely dependent on protein kinase C. These results may partially explain the mechanism by which a fructose diet induces hypertension.

  5. Population transfer of a NaH molecule via stimulated Raman adiabatic passage

    NASA Astrophysics Data System (ADS)

    Zai, Jing-Bo; Zhan, Wei-Shen; Wang, Shuo; Dang, Hai-Ping; Han, Xiao

    2016-09-01

    The population transfer of a NaH molecule from the ground state {{X}1}{Σ+} to the target state {{A}1}{Σ+} via stimulated Raman adiabatic passage (STIRAP) is investigated. The results show that the intensity, delay time and detuning have a significant effect on population transfer. A large population transfer is observed with increased pump and Stokes intensity, especially when the pump and Stokes intensity match. Population transfer also depends on the delay time between the pump laser pulse and the Stokes laser pulse. The detuning of the two pulses influences the population transfer. Efficient population transfer can be realized under the resonant or two-photon resonant condition.

  6. Bleached phase holograms exposed on Agfa-Gevaert 10E75 NAH plates

    NASA Astrophysics Data System (ADS)

    Kumar, S.; Singh, K.

    1991-02-01

    An experimental study has been made of the diffraction efficiency, scattering and stability against printout effect of bleached, photographically recorded two- beam interference gratings using Agfa-Gevaert 10E75 NAH plates. The efficiency is increased by using bleaching processes that convert the silver image into a dielectric image. Plots of the diffraction efficiency and scattering against exposure, and variation of the maximum diffraction efficiency as a function of departure from the Bragg angle, and exposure to white light, for various bleaching processes, are given. A maximum diffraction efficiency of approximately 54% has been achieved by using a potassium iodide and iodine bleach process.

  7. Room Acoustics

    NASA Astrophysics Data System (ADS)

    Kuttruff, Heinrich; Mommertz, Eckard

    The traditional task of room acoustics is to create or formulate conditions which ensure the best possible propagation of sound in a room from a sound source to a listener. Thus, objects of room acoustics are in particular assembly halls of all kinds, such as auditoria and lecture halls, conference rooms, theaters, concert halls or churches. Already at this point, it has to be pointed out that these conditions essentially depend on the question if speech or music should be transmitted; in the first case, the criterion for transmission quality is good speech intelligibility, in the other case, however, the success of room-acoustical efforts depends on other factors that cannot be quantified that easily, not least it also depends on the hearing habits of the listeners. In any case, absolutely "good acoustics" of a room do not exist.

  8. Helioseismic Holography of Simulated Sunspots: Magnetic and Thermal Contributions to Travel Times

    NASA Astrophysics Data System (ADS)

    Felipe, T.; Braun, D. C.; Crouch, A. D.; Birch, A. C.

    2016-10-01

    Wave propagation through sunspots involves conversion between waves of acoustic and magnetic character. In addition, the thermal structure of sunspots is very different than that of the quiet Sun. As a consequence, the interpretation of local helioseismic measurements of sunspots has long been a challenge. With the aim of understanding these measurements, we carry out numerical simulations of wave propagation through sunspots. Helioseismic holography measurements made from the resulting simulated wavefields show qualitative agreement with observations of real sunspots. We use additional numerical experiments to determine, separately, the influence of the thermal structure of the sunspot and the direct effect of the sunspot magnetic field. We use the ray approximation to show that the travel-time shifts in the thermal (non-magnetic) sunspot model are primarily produced by changes in the wave path due to the Wilson depression rather than variations in the wave speed. This shows that inversions for the subsurface structure of sunspots must account for local changes in the density. In some ranges of horizontal phase speed and frequency there is agreement (within the noise level in the simulations) between the travel times measured in the full magnetic sunspot model and the thermal model. If this conclusion proves to be robust for a wide range of models, it would suggest a path toward inversions for sunspot structure.

  9. Enhanced Tolerance to Naphthalene and Enhanced Rhizoremediation Performance for Pseudomonas putida KT2440 via the NAH7 Catabolic Plasmid

    PubMed Central

    Fernández, Matilde; Niqui-Arroyo, José Luis; Conde, Susana; Duque, Estrella

    2012-01-01

    In this work, we explore the potential use of the Pseudomonas putida KT2440 strain for bioremediation of naphthalene-polluted soils. Pseudomonas putida strain KT2440 thrives in naphthalene-saturated medium, establishing a complex response that activates genes coding for extrusion pumps and cellular damage repair enzymes, as well as genes involved in the oxidative stress response. The transfer of the NAH7 plasmid enables naphthalene degradation by P. putida KT2440 while alleviating the cellular stress brought about by this toxic compound, without affecting key functions necessary for survival and colonization of the rhizosphere. Pseudomonas putida KT2440(NAH7) efficiently expresses the Nah catabolic pathway in vitro and in situ, leading to the complete mineralization of [14C]naphthalene, measured as the evolution of 14CO2, while the rate of mineralization was at least 2-fold higher in the rhizosphere than in bulk soil. PMID:22582075

  10. [HYDROGEN SULFIDE DONOR, NAHS, RECOVERS CONSTITUTIVE NO SYNTHESIS AND ENDOTHELIUM-DEPENDENT RELAXATION OF ISOLATED AORTA IN OLD RATS].

    PubMed

    Drachuk, K O; Kotsjuruba, A V; Sagach, V F

    2015-01-01

    The objective of this study was to show the effect of H₂S donor, NaHS on the endothelium-dependent vasorelaxation, free radical state and cNOS uncoupling in old rats. In the aorta of old rats a combined oxidative and nitrosative stress develops that leads to cNOS uncoupling and decreased constitutive synthesis of the NO. That biochemical changes correlate with lowering of the endothelium-dependent relaxation of aortic smooth muscles (7.5 ± 1.4%, compared with 64.9 ± 3.5% in adults). It was found that, due to the combined inhibition of oxidative and nitrosative stress, NaHS restores constitutive de novo synthesis of NO by restoring cNOS coupling. Additionally, NaHS improves endothelium-dependent vasorelaxation by increasing (by 6.5 times) Ach-induced relaxation of aortic smooth muscles.

  11. White-light optical information processing and holography

    NASA Astrophysics Data System (ADS)

    Yu, Francis T.

    1987-01-01

    A report on white-light optical information processing and holography contains the following: Smeared Image Deblurring; Image Subtraction; Visualization of Phase Object; Coherence Requirement; Apparent Transfer Function; Source Encoding and Signal Sampling; Broadband Image Deblurring; Color Image Subtraction; Rainbow Holographic Aberration; Pseudocolor Encoding with Three Primary Colors; Partial Coherent Measurement; Restoration of Out of Focused Color Image; Solar Light Optical Signal Processing; White light Processing with Magnetooptic Device; Measurement of Noise Performance; White Light Fourier Holography; Optical Generation of Speech Spectrogram with White-Light Source; Progress on Archival Color Film Storage; Generating False Color Composites for LANDSAT data; Developed a Low Cost White-Light Processor; White Light Talbot Interferometer; Analysis of Cross Spectral Density Function for White Light Processing; Computer Generated Filters in White Light Processor; Holographic Tomography for 3 D Object Field; Medical Imaging with White Light; Dual Aperture Sampling with Partially Coherent Light; Application of LCTV; and Computer Generated Tricolor Sampling and Application.

  12. Stellar speckle interferometry and speckle holography at low light levels

    NASA Astrophysics Data System (ADS)

    Weigelt, G. P.

    1980-01-01

    A brief review of speckle interferometry and speckle holography techniques is presented, along with examples of each. The application of speckle interferometry to the observation of objects near a point source, i.e., the reconstruction of direct images from speckle interferograms, is discussed, as is the application of the technique for observing faint astronomical objects, such as galactic nuclei and quasars, by measuring the single photon events in speckle interferograms. The two types of measurements were performed using the ESO 3.6 m telescope and other telescopes. The techniques have been used to overcome atmospheric image degradation completely, making the resolution of the speckle measurements about 30 times higher than that of ordinary astrophotography. Speckle interferometry up to 14th magnitude has been achieved, and the measurements yielded high resolution autocorrelations of the objects. Direct images were deconvolved using the speckle holography technique.

  13. Linear programming phase unwrapping for dual-wavelength digital holography.

    PubMed

    Wang, Zhaomin; Jiao, Jiannan; Qu, Weijuan; Yang, Fang; Li, Hongru; Tian, Ailing; Asundi, Anand

    2017-01-20

    A linear programming phase unwrapping method in dual-wavelength digital holography is proposed and verified experimentally. The proposed method uses the square of height difference as a convergence standard and theoretically gives the boundary condition in a searching process. A simulation was performed by unwrapping step structures at different levels of Gaussian noise. As a result, our method is capable of recovering the discontinuities accurately. It is robust and straightforward. In the experiment, a microelectromechanical systems sample and a cylindrical lens were measured separately. The testing results were in good agreement with true values. Moreover, the proposed method is applicable not only in digital holography but also in other dual-wavelength interferometric techniques.

  14. Local magnetic structure determination using polarized neutron holography

    SciTech Connect

    Szakál, Alex Markó, Márton Cser, László

    2015-05-07

    A unique and important property of the neutron is that it possesses magnetic moment. This property is widely used for determination of magnetic structure of crystalline samples observing the magnetic components of the diffraction peaks. Investigations of diffraction patterns give information only about the averaged structure of a crystal but for discovering of local spin arrangement around a specific (e.g., impurity) nucleus remains still a challenging problem. Neutron holography is a useful tool to investigate the local structure around a specific nucleus embedded in a crystal lattice. The method has been successfully applied experimentally in several cases using non-magnetic short range interaction of the neutron and the nucleus. A mathematical model of the hologram using interaction between magnetic moment of the atom and the neutron spin for polarized neutron holography is provided. Validity of a polarized neutron holographic experiment is demonstrated by applying the proposed method on model systems.

  15. Compressive holography with a single-pixel detector.

    PubMed

    Clemente, Pere; Durán, Vicente; Tajahuerce, Enrique; Andrés, Pedro; Climent, Vicent; Lancis, Jesús

    2013-07-15

    This Letter develops a framework for digital holography at optical wavelengths by merging phase-shifting interferometry with single-pixel optical imaging based on compressive sensing. The field diffracted by an input object is sampled by Hadamard patterns with a liquid crystal spatial light modulator. The concept of a single-pixel camera is then adapted to perform interferometric imaging of the sampled diffraction pattern by using a Mach-Zehnder interferometer. Phase-shifting techniques together with the application of a backward light propagation algorithm allow the complex amplitude of the object under scrutiny to be resolved. A proof-of-concept experiment evaluating the phase distribution of an ophthalmic lens with compressive phase-shifting holography is provided.

  16. Resampling masks for phase-shifting digital holography

    NASA Astrophysics Data System (ADS)

    Zhang, Wenhui; Cao, Liangcai; Zhang, Hao; Zong, Song; Jin, Guofan

    2016-10-01

    Holographic imaging is degraded severely by the speckle or incoherent noise. In this work, resampling mask method based on phase-shifting digital holography is proposed to reduce the reconstruction noise. The zero-order and the conjugate term of the hologram can be eliminated with four-step phase-shifting digital holography (PSDH). The complex amplitude of the object after propagation can be calculated by the phase-shifting algorithm. A phase-only spatial light modulator is used to realize PSDH in the experiment. The complex amplitude is encoded into several parts by resampling masks. A high quality reconstruction image with low noise is achieved through the superposition of the individually reconstruction of coded complex amplitudes. The experiment data go well with the asymptotic function. This method can be used for digital holographic imaging of the biological samples and microstructures. Experimental results prove the feasibility of this proposed method.

  17. Monolithic focused reference beam X-ray holography

    PubMed Central

    Geilhufe, J.; Pfau, B.; Schneider, M.; Büttner, F.; Günther, C. M.; Werner, S.; Schaffert, S.; Guehrs, E.; Frömmel, S.; Kläui, M.; Eisebitt, S.

    2014-01-01

    Fourier transform holography is a highly efficient and robust imaging method, suitable for single-shot imaging at coherent X-ray sources. In its common implementation, the image contrast is limited by the reference signal generated by a small pinhole aperture. Increased pinhole diameters improve the signal, whereas the resolution is diminished. Here we report a new concept to decouple the spatial resolution from the image contrast by employing a Fresnel zone plate to provide the reference beam. Superimposed on-axis images of distinct foci are separated with a novel algorithm. Our method is insensitive to mechanical drift or vibrations and allows for long integration times common at low-flux facilities like high harmonic generation sources. The application of monolithic focused reference beams improves the efficiency of high-resolution X-ray Fourier transform holography beyond all present approaches and paves the path towards sub-10 nm single-shot X-ray imaging. PMID:24394675

  18. Fourier-Domain Holography in Photorefractive Quantum-Well Films

    NASA Astrophysics Data System (ADS)

    Jeong, Kwan; Peng, Leilei; Nolte, David D.; Melloch, Michael R.

    2004-07-01

    Fourier-domain holography (FDH) is investigated as a candidate for holographic optical coherence imaging to produce real-time images of structure inside living tissue and turbid media. The effects of spatial filtering, the background intensity distributions, and the role of background noise in determining dynamic range are evaluated for both FDH and image-domain holography (IDH). The grating washout effect in FDH (edge enhancement) is removed by use of a vibrating diffuser that consequently improves the image quality. By comparing holographic images and background images of FDH and IDH we show that FDH provides a higher dynamic range and a higher image quality than IDH for this specific application of imaging diffuse volumetric objects.

  19. Three-dimensional optical holography using a plasmonic metasurface

    PubMed Central

    Huang, Lingling; Chen, Xianzhong; Mühlenbernd, Holger; Zhang, Hao; Chen, Shumei; Bai, Benfeng; Tan, Qiaofeng; Jin, Guofan; Cheah, Kok-Wai; Qiu, Cheng-Wei; Li, Jensen; Zentgraf, Thomas; Zhang, Shuang

    2013-01-01

    Benefitting from the flexibility in engineering their optical response, metamaterials have been used to achieve control over the propagation of light to an unprecedented level, leading to highly unconventional and versatile optical functionalities compared with their natural counterparts. Recently, the emerging field of metasurfaces, which consist of a monolayer of photonic artificial atoms, has offered attractive functionalities for shaping wave fronts of light by introducing an abrupt interfacial phase discontinuity. Here we realize three-dimensional holography by using metasurfaces made of subwavelength metallic nanorods with spatially varying orientations. The phase discontinuity takes place when the helicity of incident circularly polarized light is reversed. As the phase can be continuously controlled in each subwavelength unit cell by the rod orientation, metasurfaces represent a new route towards high-resolution on-axis three-dimensional holograms with a wide field of view. In addition, the undesired effect of multiple diffraction orders usually accompanying holography is eliminated.

  20. Geometric Modeling With Image Plane Integral (IPI) Holography

    NASA Astrophysics Data System (ADS)

    Lacey, D. C. L.

    1984-10-01

    Holography has long been considered to be an ideal method of visually presenting three-dimensional data which has been either experimentally acquired or mathematically calculated with a preconceived form in mind. Unfortunately, holograms have not had the image quality and accuracy to gain scientific acceptability outside the field of interferometric analysis. This paper will describe the use of an advanced composite holographic technique to give a clear, autostereoscopic image of a computer designed automotive part and a computer graphics concept of a molecule. The holograms were manufactured using Image Plane Integral (IPI) holography on an Argon laser printer designed and built by the author. The final holograms exhibited bright, achromatic, real images with high resolution and a minimum amount of controllable distortion. Additionally, because the IPI method uses a 35mm microfilmstrip for input, it could be universally applied as a hard copy format for presentation of almost any type of three-dimensional data base.

  1. Local magnetic structure determination using polarized neutron holography

    NASA Astrophysics Data System (ADS)

    Szakál, Alex; Markó, Márton; Cser, László

    2015-05-01

    A unique and important property of the neutron is that it possesses magnetic moment. This property is widely used for determination of magnetic structure of crystalline samples observing the magnetic components of the diffraction peaks. Investigations of diffraction patterns give information only about the averaged structure of a crystal but for discovering of local spin arrangement around a specific (e.g., impurity) nucleus remains still a challenging problem. Neutron holography is a useful tool to investigate the local structure around a specific nucleus embedded in a crystal lattice. The method has been successfully applied experimentally in several cases using non-magnetic short range interaction of the neutron and the nucleus. A mathematical model of the hologram using interaction between magnetic moment of the atom and the neutron spin for polarized neutron holography is provided. Validity of a polarized neutron holographic experiment is demonstrated by applying the proposed method on model systems.

  2. High-resolution observation by double-biprism electron holography

    SciTech Connect

    Harada, Ken; Tonomura, Akira; Matsuda, Tsuyoshi; Akashi, Tetsuya; Togawa, Yoshihiko

    2004-12-01

    High-resolution electron holography has been achieved by using a double-biprism interferometer implemented on a 1 MV field emission electron microscope. The interferometer was installed behind the first magnifying lens to narrow carrier fringes and thus enabled complete separation of sideband Fourier spectrum from center band in reconstruction process. Holograms of Au fine particles and single-crystalline thin films with the finest fringe spacing of 4.2 pm were recorded and reconstructed. The overall holography system including the reconstruction process performed well for holograms in which carrier fringes had a spacing of around 10 pm. High-resolution lattice images of the amplitude and phase were clearly reconstructed without mixing of the center band and sideband information. Additionally, entire holograms were recorded without Fresnel fringes normally generated by the filament electrode of the biprism, and the holograms were thus reconstructed without the artifacts caused by Fresnel fringes.

  3. Watermarking of three-dimensional objects by digital holography

    NASA Astrophysics Data System (ADS)

    Kishk, Sherif; Javidi, Bahram

    2003-02-01

    We present an optical method for information watermarking of three-dimensional (3D) objects by digital holography. A hidden image is embedded by double phase encoding in a phase-shift digital hologram of the 3D object. We decode the watermarked hologram to reconstruct the hidden image and the 3D object. We use either the entire hologram or a part of it to decode the hidden image. Experiments are presented to illustrate the ability to recover both the 3D object and the decoded hidden image. Digital holograms of the 3D object are obtained by optical experiments. The watermarking process, 3D object reconstruction, and hidden image recovery are performed digitally. To the best of our knowledge, this is the first report of 3D object watermarking by use of a phase encoding technique and digital holography.

  4. In vitro functional characterization of the Na+/H+ antiporters in Corynebacterium glutamicum.

    PubMed

    Xu, Ning; Wang, Lei; Cheng, Haijiao; Liu, Qingdai; Liu, Jun; Ma, Yanhe

    2016-02-01

    Corynebacterium glutamicum, typically used as industrial workhorse for amino acid production, is a moderately salt-alkali-tolerant microorganism with optimal growth at pH 7-9. However, little is known about the mechanisms of salt-alkali tolerance in C. glutamicum. Here, the catalytic capacity of three putative Na(+)/H(+) antiporters from C. glutamicum (designated as Cg-Mrp1, Cg-Mrp2 and Cg-NhaP) were characterized in an antiporter-deficient Escherichia coli KNabc strain. Only Cg-Mrp1 was able to effectively complement the Na(+)-sensitive of E. coli KNabc. Cg-Mrp1 exhibited obvious Na(+)(Li(+))/H(+) antiport activities with low apparent Km values of 1.08 mM and 1.41 mM for Na(+) and Li(+), respectively. The Na(+)/H(+) antiport activity of Cg-Mrp1 was optimal in the alkaline pH range. All three antiporters showed detectable K(+)/H(+) antiport activitiy. Cg-NhaP also exhibited Na(+)(Li(+),Rb(+))/H(+) antiport activities but at lower levels of activity. Interestingly, overexpression of Cg-Mrp2 exhibited clear Na(+)(K(+))/H(+) antiport activities. These results suggest that C. glutamicum Na(+)(K(+))/H(+) antiporters may have overlapping roles in coping with salt-alkali and perhaps high-osmolarity stress.

  5. Effects of the Electronic Doping In the Stability of the Metal Hydride NaH

    NASA Astrophysics Data System (ADS)

    Olea-Amezcua, Monica-Araceli; Rivas-Silva, Juan-Francisco; de La Peña-Seaman, Omar; Heid, Rolf; Bohnen, Klaus-Peter

    2015-03-01

    Despite metal hydrides light weight and high hydrogen volumetric densities, the Hydrogen desorption process requires excessively high temperatures due to their high stability. Attempts for improvement the hydrogenation properties have been focus on the introduction of defects, impurities and doping on the metal hydride. We present a systematic study of the electronic doping effects on the stability of a model system, NaH doped with magnesium, forming the alloying system Na1-xMgxH. We use the density functional theory (DFT) and the self-consistent version of the virtual crystal approximation (VCA) to model the doping of NaH with Mg. The evolution of the ground state structural and electronic properties is analyzed as a function of Mg-content. The full-phonon dispersion, calculated by the linear response theory (LRT) and density functional perturbation theory (DFPT), is analyzed for several Mg-concentrations, paying special attention to the crystal stability and the correlations with the electronic structure. Applying the quasiharmonic approximation (QHA), the free energy from zero-point motion is obtained, and its influence on the properties under study is analyzed. This work is partially supported by the VIEP-BUAP (OMPS-EXC14-I) and CONACYT-Mexico (No. 221807) projects.

  6. Integrating mass spectrometry with MD simulations reveals the role of lipids in Na+/H+ antiporters

    PubMed Central

    Landreh, Michael; Marklund, Erik G.; Uzdavinys, Povilas; Degiacomi, Matteo T.; Coincon, Mathieu; Gault, Joseph; Gupta, Kallol; Liko, Idlir; Benesch, Justin L. P.; Drew, David; Robinson, Carol V.

    2017-01-01

    Na+/H+ antiporters are found in all kingdoms of life and exhibit catalysis rates that are among the fastest of all known secondary-active transporters. Here we combine ion mobility mass spectrometry and molecular dynamics simulations to study the conformational stability and lipid-binding properties of the Na+/H+ exchanger NapA from Thermus thermophilus and compare this to the prototypical antiporter NhaA from Escherichia coli and the human homologue NHA2. We find that NapA and NHA2, but not NhaA, form stable dimers and do not selectively retain membrane lipids. By comparing wild-type NapA with engineered variants, we show that the unfolding of the protein in the gas phase involves the disruption of inter-domain contacts. Lipids around the domain interface protect the native fold in the gas phase by mediating contacts between the mobile protein segments. We speculate that elevator-type antiporters such as NapA, and likely NHA2, use a subset of annular lipids as structural support to facilitate large-scale conformational changes within the membrane. PMID:28071645

  7. Na+-H+ exchanger-1 (NHE1) regulation in kidney proximal tubule.

    PubMed

    Parker, Mark D; Myers, Evan J; Schelling, Jeffrey R

    2015-06-01

    The ubiquitously expressed plasma membrane Na(+)-H(+) exchanger NHE1 is a 12 transmembrane-spanning protein that directs important cell functions such as homeostatic intracellular volume and pH control. The 315 amino acid cytosolic tail of NHE1 binds plasma membrane phospholipids and multiple proteins that regulate additional, ion-translocation independent functions. This review focuses on NHE1 structure/function relationships, as well as the role of NHE1 in kidney proximal tubule functions, including pH regulation, vectorial Na(+) transport, cell volume control and cell survival. The implications of these functions are particularly critical in the setting of progressive, albuminuric kidney diseases, where the accumulation of reabsorbed fatty acids leads to disruption of NHE1-membrane phospholipid interactions and tubular atrophy, which is a poor prognostic factor for progression to end stage renal disease. This review amplifies the vital role of the proximal tubule NHE1 Na(+)-H(+) exchanger as a kidney cell survival factor.

  8. Integrating mass spectrometry with MD simulations reveals the role of lipids in Na(+)/H(+) antiporters.

    PubMed

    Landreh, Michael; Marklund, Erik G; Uzdavinys, Povilas; Degiacomi, Matteo T; Coincon, Mathieu; Gault, Joseph; Gupta, Kallol; Liko, Idlir; Benesch, Justin L P; Drew, David; Robinson, Carol V

    2017-01-10

    Na(+)/H(+) antiporters are found in all kingdoms of life and exhibit catalysis rates that are among the fastest of all known secondary-active transporters. Here we combine ion mobility mass spectrometry and molecular dynamics simulations to study the conformational stability and lipid-binding properties of the Na(+)/H(+) exchanger NapA from Thermus thermophilus and compare this to the prototypical antiporter NhaA from Escherichia coli and the human homologue NHA2. We find that NapA and NHA2, but not NhaA, form stable dimers and do not selectively retain membrane lipids. By comparing wild-type NapA with engineered variants, we show that the unfolding of the protein in the gas phase involves the disruption of inter-domain contacts. Lipids around the domain interface protect the native fold in the gas phase by mediating contacts between the mobile protein segments. We speculate that elevator-type antiporters such as NapA, and likely NHA2, use a subset of annular lipids as structural support to facilitate large-scale conformational changes within the membrane.

  9. Integrating mass spectrometry with MD simulations reveals the role of lipids in Na+/H+ antiporters

    NASA Astrophysics Data System (ADS)

    Landreh, Michael; Marklund, Erik G.; Uzdavinys, Povilas; Degiacomi, Matteo T.; Coincon, Mathieu; Gault, Joseph; Gupta, Kallol; Liko, Idlir; Benesch, Justin L. P.; Drew, David; Robinson, Carol V.

    2017-01-01

    Na+/H+ antiporters are found in all kingdoms of life and exhibit catalysis rates that are among the fastest of all known secondary-active transporters. Here we combine ion mobility mass spectrometry and molecular dynamics simulations to study the conformational stability and lipid-binding properties of the Na+/H+ exchanger NapA from Thermus thermophilus and compare this to the prototypical antiporter NhaA from Escherichia coli and the human homologue NHA2. We find that NapA and NHA2, but not NhaA, form stable dimers and do not selectively retain membrane lipids. By comparing wild-type NapA with engineered variants, we show that the unfolding of the protein in the gas phase involves the disruption of inter-domain contacts. Lipids around the domain interface protect the native fold in the gas phase by mediating contacts between the mobile protein segments. We speculate that elevator-type antiporters such as NapA, and likely NHA2, use a subset of annular lipids as structural support to facilitate large-scale conformational changes within the membrane.

  10. Bi-local holography in the SYK model

    DOE PAGES

    Jevicki, Antal; Suzuki, Kenta; Yoon, Junggi

    2016-07-01

    We discuss large N rules of the Sachdev-Ye-Kitaev model and the bi-local representation of holography of this theory. This is done by establishing 1/N Feynman rules in terms of bi-local propagators and vertices, which can be evaluated following the recent procedure of Polchinski and Rosenhaus. Lastly, these rules can be interpreted as Witten type diagrams of the dual AdS theory, which we are able to define at IR fixed point and off.

  11. Holography and entropy bounds in the plane wave matrix model

    SciTech Connect

    Bousso, Raphael; Mints, Aleksey L.

    2006-06-15

    As a quantum theory of gravity, matrix theory should provide a realization of the holographic principle, in the sense that a holographic theory should contain one binary degree of freedom per Planck area. We present evidence that Bekenstein's entropy bound, which is related to area differences, is manifest in the plane wave matrix model. If holography is implemented in this way, we predict crossover behavior at strong coupling when the energy exceeds N{sup 2} in units of the mass scale.

  12. Multiwavelength parallel phase-shifting digital holography using angular multiplexing.

    PubMed

    Tahara, Tatsuki; Ito, Yasunori; Lee, Yonghee; Xia, Peng; Inoue, Junichi; Awatsuji, Yasuhiro; Nishio, Kenzo; Ura, Shogo; Kubota, Toshihiro; Matoba, Osamu

    2013-08-01

    We propose a single-shot digital holography for recording multiwavelength and complex amplitude information by using a single monochromatic image sensor. The zeroth-order wave and conjugate image in each wavelength are removed from a recorded single hologram by applying parallel phase-shifting interferometry. Angular multiplexing is utilized to record the complex amplitude of an object wave in each wavelength separately, and no color filter is required. The effectiveness of the proposed technique was experimentally verified.

  13. The microwave holography system for the Sardinia Radio Telescope

    NASA Astrophysics Data System (ADS)

    Serra, G.; Bolli, P.; Busonera, G.; Pisanu, T.; Poppi, S.; Gaudiomonte, F.; Zacchiroli, G.; Roda, J.; Morsiani, M.; López-Pérez, J. A.

    2012-09-01

    Microwave holography is a well-established technique for mapping surface errors of large reflector antennas, particularly those designed to operate at high frequencies. We present here a holography system based on the interferometric method for mapping the primary reflector surface of the Sardinia Radio Telescope (SRT). SRT is a new 64-m-diameter antenna located in Sardinia, Italy, equipped with an active surface and designed to operate up to 115 GHz. The system consists mainly of two radio frequency low-noise coherent channels, designed to receive Ku-band digital TV signals from geostationary satellites. Two commercial prime focus low-noise block converters are installed on the radio telescope under test and on a small reference antenna, respectively. Then the signals are amplified, filtered and downconverted to baseband. An innovative digital back-end based on FPGA technology has been implemented to digitize two 5 MHz-band signals and calculate their cross-correlation in real-time. This is carried out by using a 16-bit resolution ADCs and a FPGA reaching very large amplitude dynamic range and reducing post-processing time. The final holography data analysis is performed by CLIC data reduction software developed within the Institut de Radioastronomie Millimétrique (IRAM, Grenoble, France). The system was successfully tested during several holography measurement campaigns, recently performed at the Medicina 32-m radio telescope. Two 65-by-65 maps, using an on-the-fly raster scan with on-source phase calibration, were performed pointing the radio telescope at 38 degrees elevation towards EUTELSAT 7A satellite. The high SNR (greater than 60 dB) and the good phase stability led to get an accuracy on the surface error maps better than 150 μm RMS.

  14. Feasibility of microwave holography for imaging the sea surface

    NASA Technical Reports Server (NTRS)

    Wells, W.

    1972-01-01

    The possibility of imaging the sea surface in three dimensions by means of microwave holography from a low-flying aircraft is considered. Data cover a brief feasibility study and a review of some computer experiments in which it was demonstrated that it is possible to compute three-dimensional images of objects from raw holographic data recorded on magnetic tape. These experiments used synthetic data.

  15. Hydrogen sulfide donor NaHS induces death of alveolar epithelial L2 cells that is associated with cellular shrinkage, transgelin expression and myosin phosphorylation.

    PubMed

    Fujii, Yusuke; Funakoshi, Takeshi; Unuma, Kana; Noritake, Kanako; Aki, Toshihiko; Uemura, Koichi

    2016-01-01

    Hydrogen sulfide (H2S) is a highly toxic gaseous molecule that causes death to humans exposed to high concentrations. H2S is absorbed into the body through the alveolar epithelium and other tissues. The aim of this study is to evaluate the molecular mechanism underling acute lung injury caused by the inhalation of high concentrations of H2S. Rat lung epithelium-derived L2 cells were exposed to a H2S donor, NaHS, at concentrations of 2-4 mM for 1-6 hr. NaHS caused shrinkage and death of the cells without caspase activation. An actin-binding protein, transgelin, was identified as one of the NaHS-inducible proteins in the cells. NaHS increased myosin light chain (MLC) phosphorylation, indicating that actomyosin-mediated cellular contractility and/or motility could be increased after NaHS exposure. The administration of ML-7, a myosin light chain kinase (MLCK) inhibitor, accelerated cell death after NaHS exposure. Based on these data, we conclude that the increase in MLC phosphorylation in response to NaHS exposure is a cellular protective reaction against NaHS toxicity. Enhancements in smooth muscle cell properties such as transgelin expression and actomyosin-mediated contractility/motility might be involved in cell survival after NaHS exposure.

  16. Large-format automated pulsed holography camera system

    NASA Astrophysics Data System (ADS)

    Rodin, Alexey M.; Ratcliffe, David B.; Rus, Roman

    2001-04-01

    An automated pulsed holography camera system for ultra-large format display holography has been created. This camera produces reflection and rainbow copies of up to 110 X 150 cm size as well as master holograms of up to 80 X 100 cm size. In addition, the system is capable of generating digital full color transmission rainbow holograms from masters produced by a digital mastering machine. Camera utilizes the single longitudinal mode-phase conjugated laser delivering the pulses of 35 ns duration with maximum energy of 8 J at 526.5 nm wavelength. High output energy have conditioned the use of non-spherical spatial beam filtering in each beam pass. Camera incorporates instant switch-over from copying to mastering modes, permits digital electronic setting of all beam ratios and allows manual tuning of scene illuminating diffusers. Some of the most important applications of this camera are printing of AO format 3D-drawings for advanced virtual prototyping of machines & devices, large format scientific & artistic holography, 3D-posters printing industry of near future.

  17. Computer Generated Holography with Intensity-Graded Patterns

    PubMed Central

    Conti, Rossella; Assayag, Osnath; de Sars, Vincent; Guillon, Marc; Emiliani, Valentina

    2016-01-01

    Computer Generated Holography achieves patterned illumination at the sample plane through phase modulation of the laser beam at the objective back aperture. This is obtained by using liquid crystal-based spatial light modulators (LC-SLMs), which modulate the spatial phase of the incident laser beam. A variety of algorithms is employed to calculate the phase modulation masks addressed to the LC-SLM. These algorithms range from simple gratings-and-lenses to generate multiple diffraction-limited spots, to iterative Fourier-transform algorithms capable of generating arbitrary illumination shapes perfectly tailored on the base of the target contour. Applications for holographic light patterning include multi-trap optical tweezers, patterned voltage imaging and optical control of neuronal excitation using uncaging or optogenetics. These past implementations of computer generated holography used binary input profile to generate binary light distribution at the sample plane. Here we demonstrate that using graded input sources, enables generating intensity graded light patterns and extend the range of application of holographic light illumination. At first, we use intensity-graded holograms to compensate for LC-SLM position dependent diffraction efficiency or sample fluorescence inhomogeneity. Finally we show that intensity-graded holography can be used to equalize photo evoked currents from cells expressing different levels of chanelrhodopsin2 (ChR2), one of the most commonly used optogenetics light gated channels, taking into account the non-linear dependence of channel opening on incident light. PMID:27799896

  18. In-line particle field holography at Pegasus

    SciTech Connect

    Sorenson, D.S.; Obst, A.; King, N.S.P.

    1995-09-01

    An in-line holographic imaging system has been developed for hydrodynamic experiments at the Pegasus facility located at Los Alamos National Laboratory. Holography offers the unique capability to record distributions of particles over a three dimensional volume. The system to be discussed is used to measure particle distributions of ejecta emitted after a cylindrical aluminum liner (5.0 cm in diameter, 2.0 cm high) impacts a target (3.0 cm in diameter). The ejecta emerges from the target traveling up to 7mm/{micro}s and moves toward the axial center of the system where the holographic imaging is performed. In-line holography is particularly suited for the Pegasus pulsed power facility where the geometry restrictions make off axis holography impractical. In order to record the fast moving particles a frequency-doubled Nd:-YAG laser system has been implemented which produces a 80 ps 20 millijoule pulse at 532 nm. An optical relay system composed of a Fourier optical lens pair has been developed which is placed 4.0 cm from the center of the region of interest. This relay lens pair forms an intermediate image 32 cm from the object plane and the hologram is placed 4cm downstream of the intermediate image. The holographic system and resolution capability are discussed.

  19. Multicolor 3D meta-holography by broadband plasmonic modulation

    PubMed Central

    Li, Xiong; Chen, Lianwei; Li, Yang; Zhang, Xiaohu; Pu, Mingbo; Zhao, Zeyu; Ma, Xiaoliang; Wang, Yanqin; Hong, Minghui; Luo, Xiangang

    2016-01-01

    As nanofabrication technology progresses, the emerging metasurface has offered unique opportunities for holography, such as an increased data capacity and the realization of polarization-sensitive functionality. Multicolor three-dimensional (3D) meta-hologram imaging is one of the most pursued applications for meta-hologram not yet realized. How to reduce the cross-talk among different colors in broad bandwidth designs is a critical question. On the basis of the off-axis illumination method, we develop a novel way to overcome the cross-talk limitation and achieve multicolor meta-holography with a single type of plasmonic pixel. With this method, the usable data capacity can also be improved. It not only leads to a remarkable image quality, with a signal-to-noise ratio (SNR) five times better than that of the previous meta-hologram designs, but also paves the way to new meta-hologram devices, which mark an advance in the field of meta-holography. For example, a seven-color meta-hologram can be fabricated with a color gamut 1.39 times larger than that of the red, green, and blue (RGB) design. For the first time, a full-color meta-holographic image in the 3D space is also experimentally demonstrated. Our approach to expanding the information capacity of the meta-hologram is unique, which extends broad applications in data storage, security, and authentication. PMID:27847867

  20. Spatial crystal imaging by means of atomic electron holography

    NASA Astrophysics Data System (ADS)

    Luehr, Tobias; Winkelmann, Aimo; Nolze, Gert; Westphal, Carsten

    2015-03-01

    The determination of atom structures is the key for the understanding of basic functional properties of matter or for designing new high-tech materials. For structure determination, holography is a very attractive option, since this method enables lensless three-dimensional imaging. In principle, x-ray photoelectron diffraction (XPD) experiments correspond to a microscopic holography setup. The electron diffraction pattern is highly sensitive to the local structure of the emitter environment, since the emitting atom is located in the near-field of the scattering atoms. Hence, holographic reconstructions of XPD-patterns should yield a spatial image of the sample's atom arrangement. However, anisotropic electron scattering and multiple scattering effects generally cause strong artifacts in the reconstruction. In this contribution we show how to circumvent this problem with electrons at kinetic energies of Ekin >= 10 keV. The resulting spatial images contain hundreds of clearly separated atoms at their correct locations. Furthermore, XPD-patterns allow an element-specific assignment of the reconstructed atoms within the image. This is the first demonstration of true atom imaging following Dennis Gabor's idea of electron holography.

  1. Ultra-realistic imaging: a new beginning for display holography

    NASA Astrophysics Data System (ADS)

    Bjelkhagen, Hans I.; Brotherton-Ratcliffe, David

    2014-02-01

    Recent improvements in key foundation technologies are set to potentially transform the field of Display Holography. In particular new recording systems, based on recent DPSS and semiconductor lasers combined with novel recording materials and processing, have now demonstrated full-color analogue holograms of both lower noise and higher spectral accuracy. Progress in illumination technology is leading to a further major reduction in display noise and to a significant increase of the clear image depth and brightness of such holograms. So too, recent progress in 1-step Direct-Write Digital Holography (DWDH) now opens the way to the creation of High Virtual Volume Displays (HVV) - large format full-parallax DWDH reflection holograms having fundamentally larger clear image depths. In a certain fashion HVV displays can be thought of as providing a high quality full-color digital equivalent to the large-format laser-illuminated transmission holograms of the sixties and seventies. Back then, the advent of such holograms led to much optimism for display holography in the market. However, problems with laser illumination, their monochromatic analogue nature and image noise are well cited as being responsible for their failure in reality. Is there reason for believing that the latest technology improvements will make the mark this time around? This paper argues that indeed there is.

  2. Particle distribution measurements using in line Fraunhofer holography

    SciTech Connect

    Sorenson, D.; Malone, R.; Frogget, B.; Ciarcia, C.; Tunnell, T.; Flurer, R.

    1996-10-01

    In-line Fraunhofer holography has been developed and implemented at Los Alamos National Laboratory to measure particle distributions of fast moving particles. Holography is a unique diagnostic that gives unambiguous information on the size and shapes of particle distributions over a three dimensional volume. Currently, the capability of measuring particles two microns in size which travel many mm/{mu}sec has been demonstrated in hydrodynamic experiments at the Pegasus Pulsed Power Facility. Normally, for setting up an in- line holography experiment for measuring particles a few microns in size, the holographic film would be placed less than one centimeter from the particles. However, due to the high energy associated with the dynamic experiment, an optical relay system is used to relay the interference pattern 35 cm so that glass hologram will survive. After the hologram has been made the data must be extracted. This is accomplished by using a laser to reconstruct the data in space. This three dimensional image is then digitized via a CCD camera and a three axis actuator system. After the data has been digitized it is then analyzed with intelligent image processing algorithms. Details will be described below.

  3. CHRONICLE: First International School on Coherent Optics and Holography (Prague, September 1-12, 1980)

    NASA Astrophysics Data System (ADS)

    Bukhenskiĭ, M. F.; Semenov, A. S.

    1981-07-01

    A brief review is given of papers presented at the First International School on Coherent Optics and Holography (Prague, 1980) and at the Second Czechoslovak Conference on Integrated Optics. The School was organized in sessions on coherence of light, fiber optics, integrated optics, holography, optical diagnostic methods, and adaptive optics.

  4. Heterodyne holography with full control of both the signal and reference arms.

    PubMed

    Gross, Michel

    2016-01-20

    Heterodyne holography is a variant of phase-shifting holography in which the reference and signal arms are controlled by acousto-optic modulators. In this review paper, we will briefly describe the method and its properties, and we will illustrate its advantages in experimental applications.

  5. Talbot self-image effect in digital holography and its application to spectrometry.

    PubMed

    De Nicola, Sergio; Ferraro, Pietro; Coppola, Giuseppe; Finizio, Andrea; Pierattini, Giovanni; Grilli, Simonetta

    2004-01-01

    For the first time to the authors' knowledge, the Talbot effect has been observed and investigated in digital holography. By numerical reconstruction of holograms, the Talbot self-imaging phenomenon is observed by reconstruction of the amplitude of the image at different distances and (or) wavelengths. A simple spectrometer based on Talbot self-imaging in digital holography is proposed and demonstrated.

  6. Acoustic biosensors

    PubMed Central

    Fogel, Ronen; Seshia, Ashwin A.

    2016-01-01

    Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of cost, size and scalability, as well as potential additional features including integration with microfluidics and electronics, scaled sensitivities associated with smaller dimensions and higher operational frequencies, the ability to multiplex detection across arrays of hundreds of devices embedded in a single chip, increased throughput and the ability to interrogate a wider range of modes including within the same device. Additionally, device fabrication is often compatible with semiconductor volume batch manufacturing techniques enabling cost scalability and a high degree of precision and reproducibility in the manufacturing process. Integration with microfluidics handling also enables suitable sample pre-processing/separation/purification/amplification steps that could improve selectivity and the overall signal-to-noise ratio. Three device types are reviewed here: (i) bulk acoustic wave sensors, (ii) surface acoustic wave sensors, and (iii) micro/nano-electromechanical system (MEMS/NEMS) sensors. PMID:27365040

  7. Acoustic biosensors.

    PubMed

    Fogel, Ronen; Limson, Janice; Seshia, Ashwin A

    2016-06-30

    Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of cost, size and scalability, as well as potential additional features including integration with microfluidics and electronics, scaled sensitivities associated with smaller dimensions and higher operational frequencies, the ability to multiplex detection across arrays of hundreds of devices embedded in a single chip, increased throughput and the ability to interrogate a wider range of modes including within the same device. Additionally, device fabrication is often compatible with semiconductor volume batch manufacturing techniques enabling cost scalability and a high degree of precision and reproducibility in the manufacturing process. Integration with microfluidics handling also enables suitable sample pre-processing/separation/purification/amplification steps that could improve selectivity and the overall signal-to-noise ratio. Three device types are reviewed here: (i) bulk acoustic wave sensors, (ii) surface acoustic wave sensors, and (iii) micro/nano-electromechanical system (MEMS/NEMS) sensors.

  8. Higher-spin theory and holography

    NASA Astrophysics Data System (ADS)

    Gaberdiel, Matthias; Vasiliev, Mikhail

    2013-05-01

    , this has triggered a significant amount of activity in this general area. Among other things, the constraints that are implied by the higher-spin symmetries were analysed (see the paper by Maldacena and Zhiboedov in this issue [9]), and a fairly concrete proposal for how higher-spin theories are related to string theory was made (see the paper by Chang, Minwalla, Sharma and Yin in this issue [10]). Furthermore, a lower dimensional version of the conjecture was put forward by Gaberdiel and Gopakumar [11] that was subsequently also checked in some detail. These dualities hold the promise of offering insights into the inner workings of the AdS/CFT correspondence since they are complex enough to capture the essence of the duality, while at the same time being sufficiently simple in order to allow for a detailed analysis. Moreover, the methods specifically developed in higher-spin theory may be useful for understanding a general mechanism underlying holography, both in higher-spin models and beyond (see the paper by Vasiliev in this issue [12]). Another fascinating aspect of these higher-spin theories lies in the fact that the higher-spin symmetries mix generically fields of different spin, and in particular, the spin-2 metric and higher-spin excitations are related to one another by gauge transformations. As a result, higher-spin theories require a modification of the standard framework of Riemannian geometry since the usual diffeomorphism-invariant tensors are not gauge invariant any longer. In particular, higher-spin theories may therefore open the way towards understanding fundamental concepts of space-time geometry; for example, they may well have key lessons in store for how string theory resolves space-time singularities. In this issue we have collected together a number of review papers, summarizing the aforementioned recent developments, as well as research papers indicating current directions of interest in the study of higher-spin gauge theories. We hope that it

  9. Grape Marc Extract-Induced Defense Reactions and Protection against Phytophthora parasitica Are Impaired in NahG Tobacco Plants.

    PubMed

    Benouaret, Razik; Goupil, Pascale

    2015-08-05

    Grape marc extract (GME) acts as an elicitor of plant defense responses. This study analyzed GME-induced plant defense reactions in NahG transgenic tobacco. Leaf infiltration of NahG leaves revealed HR-like reactions with reduced lesions and weak deployment of autofluorescent compounds in the surrounding infiltrated tissues. The β-1,3-glucanase PR2-, endochitinase PR3-, and osmotin PR5-target transcript levels were strongly lowered in NahG leaves, and the mutant failed to accumulate the antimicrobial PR1 transcripts. GME-induced protection against Phytophthora parasitica var. nicotianae (Ppn) was evaluated on tobacco leaves. The antimicrobial properties of GME against Ppn were evidenced using a range of in vitro tests. GME-sprayed wild-type leaves showed reduced infection areas, whereas GME failed to induce a protective effect against Ppn in NahG leaves. The results suggest that GME-induced plant defense reactions in tobacco plants was mediated by salicylic acid (SA) and that GME-induced protection against Ppn could be the combined result of antimicrobial and defense actions.

  10. Molecular cloning and expression of a cDNA encoding the rabbit ileal villus cell basolateral membrane Na+/H+ exchanger.

    PubMed Central

    Tse, C M; Ma, A I; Yang, V W; Watson, A J; Levine, S; Montrose, M H; Potter, J; Sardet, C; Pouyssegur, J; Donowitz, M

    1991-01-01

    A cDNA clone encoding a rabbit ileal villus cell Na+/H+ exchanger was isolated and its complete nucleotide sequence was determined. The cDNA is 4 kb long and contains 322 bp of 5'-untranslated region, 2451 bp of open reading frame and 1163 bp of 3'-untranslated area, with 70%, 91% and 40% identity to the human sequence, respectively. Amino acid sequence deduced from the longest open reading frame indicated a protein of 816 residues (predicted Mr 90,716) which exhibits 95% amino acid identity to the human Na+/H+ exchanger. The two putative glycosylation sites in the human Na+/H+ exchanger are conserved in this protein, suggesting that it is a glycoprotein. Stable transfection of the cDNA into an Na+/H+ exchanger deficient fibroblast cell line, established Na+/H+ exchange. The Na+/H+ exchanger was stimulated by serum and a phorbol ester but not by 8-Br-cAMP. In Northern blot analysis, the cDNA hybridized to a 4.8 kb message in rabbit ileal villus cells, kidney cortex, kidney medulla, adrenal gland, brain and descending colon and to a 5.2 kb message in cultured human colonic cancer cell lines, HT29-18 and Caco-2. In immunoblotting, a polyclonal antibody raised against a fusion protein of beta-galactosidase and the C-terminal 158 amino acids of the human Na+/H+ exchanger identified a rabbit ileal basolateral membrane protein of 94 kd and only weakly interacted with the ileal brush border membrane. In immunocytochemical studies using ileal villus and crypt epithelial cells, the same antibody identified basolateral and not brush border epitopes. Restriction analysis of genomic DNA with a 462 bp PstI-AccI fragment of the rabbit Na+/H+ exchanger strongly suggests the existence of closely related Na+/H+ exchanger genes. The near identity of the basolateral Na+/H+ exchanger and the human Na+/H+ exchanger plus the ubiquitous expression of this message suggests that the ileal basolateral Na+/H+ exchanger is the 'housekeeping' Na+/H+ exchanger. Images PMID:1712287

  11. Nonlinear Acoustics

    DTIC Science & Technology

    1974-02-14

    Wester- velt. [60] Streaming. In 1831, Michael Faraday [61] noted that currents of air were set up in the neighborhood of vibrating plates-the first... ducei in the case of a paramettc amy (from Berktay an Leahy 141). C’ "". k•, SEC 10.1 NONLINEAR ACOUSTICS 345 The principal results of their analysis

  12. Differential Stimulation of the Na+/H+ Exchanger Determines Chloroquine Uptake in Plasmodium falciparum

    PubMed Central

    Wünsch, Stefan; Sanchez, Cecilia P.; Gekle, Michael; Große-Wortmann, Lars; Wiesner, Jochen; Lanzer, Michael

    1998-01-01

    Here we describe the identification and characterization of a physiological marker that is associated with the chloroquine-resistant (CQR) phenotype in the human malarial parasite Plasmodium falciparum. Single cell in vivo pH measurements revealed that CQR parasites consistently have an elevated cytoplasmic pH compared to that of chloroquine-sensitive (CQS) parasites because of a constitutively activated Na+/H+ exchanger (NHE). Together, biochemical and physiological data suggest that chloroquine activates the plasmodial NHE of CQS parasites, resulting in a transitory phase of rapid sodium/hydrogen ion exchange during which chloroquine is taken up by this protein. The constitutively stimulated NHE of CQR parasites are capable of little or no further activation by chloroquine. We propose that the inability of chloroquine to stimulate its own uptake through the constitutively activated NHE of resistant parasites constitutes a minimal and necessary event in the generation of the chloroquine-resistant phenotype. PMID:9442109

  13. Regulation of early neurite morphogenesis by the Na+/H+ exchanger NHE1.

    PubMed

    Sin, Wun-Chey; Moniz, David M; Ozog, Mark A; Tyler, Jessica E; Numata, Masayuki; Church, John

    2009-07-15

    The ubiquitously expressed Na(+)/H(+) exchanger NHE1 plays an important role in regulating polarized membrane protrusion and directional motility in non-neuronal cells. Using NGF-differentiated PC12 cells and murine neocortical neurons in vitro, we now show that NHE1 plays a role in regulating early neurite morphogenesis. NHE1 was expressed in growth cones in which it gave rise to an elevated intracellular pH in actively extending neurites. The NHE1 inhibitor cariporide reversibly reduced growth cone filopodia number and the formation and elongation of neurites, especially branches, whereas the transient overexpression of full-length NHE1, but not NHE1 mutants deficient in either ion translocation activity or actin cytoskeletal anchoring, elicited opposite effects. In addition, compared with neocortical neurons obtained from wild-type littermates, neurons isolated from NHE1-null mice exhibited reductions in early neurite outgrowth, an effect that was rescued by overexpression of full-length NHE1 but not NHE1 mutants. Finally, the growth-promoting effects of netrin-1, but not BDNF or IGF-1, were markedly reduced by cariporide in wild-type neocortical neurons and were not observed in NHE1-null neurons. Although netrin-1 failed to increase growth cone intracellular pH or Na(+)/H(+) exchange activity, netrin-1-induced increases in early neurite outgrowth were restored in NHE1-null neurons transfected with full-length NHE1 but not an ion translocation-deficient mutant. Collectively, the results indicate that NHE1 participates in the regulation of early neurite morphogenesis and identify a novel role for NHE1 in the promotion of early neurite outgrowth by netrin-1.

  14. Nax loci affect SOS1-like Na+/H+ exchanger expression and activity in wheat

    PubMed Central

    Zhu, Min; Shabala, Lana; Cuin, Tracey A; Huang, Xin; Zhou, Meixue; Munns, Rana; Shabala, Sergey

    2016-01-01

    Salinity stress tolerance in durum wheat is strongly associated with a plant’s ability to control Na+ delivery to the shoot. Two loci, termed Nax1 and Nax2, were recently identified as being critical for this process and the sodium transporters HKT1;4 and HKT1;5 were identified as the respective candidate genes. These transporters retrieve Na+ from the xylem, thus limiting the rates of Na+ transport from the root to the shoot. In this work, we show that the Nax loci also affect activity and expression levels of the SOS1-like Na+/H+ exchanger in both root cortical and stelar tissues. Net Na+ efflux measured in isolated steles from salt-treated plants, using the non-invasive ion flux measuring MIFE technique, decreased in the sequence: Tamaroi (parental line)>Nax1=Nax2>Nax1:Nax2 lines. This efflux was sensitive to amiloride (a known inhibitor of the Na+/H+ exchanger) and was mirrored by net H+ flux changes. TdSOS1 relative transcript levels were 6–10-fold lower in Nax lines compared with Tamaroi. Thus, it appears that Nax loci confer two highly complementary mechanisms, both of which contribute towards reducing the xylem Na+ content. One enhances the retrieval of Na+ back into the root stele via HKT1;4 or HKT1;5, whilst the other reduces the rate of Na+ loading into the xylem via SOS1. It is suggested that such duality plays an important adaptive role with greater versatility for responding to a changing environment and controlling Na+ delivery to the shoot. PMID:26585227

  15. Na+/H+ exchange inhibition delays the onset of hypovolemic circulatory shock in pigs.

    PubMed

    Wu, Dongmei; Arias, Jaqueline; Bassuk, Jorge; Doods, Henri; Seidler, Randolph; Adams, Jose A; Abraham, William M

    2008-04-01

    Severe blood loss is a major cause of death occurring within hours of traumatic injury. Na+/H+ exchange (NHE-1) activity is an important determinant of the extent of ischemic myocardial injury. The goal of the present study was to test the hypothesis that NHE-1 inhibition delays the onset of hypovolemic circulatory shock, thereby preventing early death due to severe hemorrhage in pigs. Severe hypovolemia was studied in 16 (25.2 kg) anesthetized male pigs in steps of 10-, 20-, 30-, 40-, and 50-mL kg(-1) blood loss, each in 30-min intervals. Shed blood resuscitation was started 30 min after 50 mL kg(-1) blood loss. The experiment was terminated after 3 h of resuscitation. Eight pigs were used as seline control. Eight pigs received 3 mg kg(-1) benzamide, N-(aminoiminomethyl)-4-[4-(2-furanylcarbonyl)-1-piperazinyl]-3-(methylsulfonyl), methanesulfonate (NHE-1 inhibitor) 15 min before hemorrhage. Seven control pigs died at 40- to 50-mL kg(-1) blood loss. One control pig survived initial resuscitation but died soon after. In contrast, all animals treated with NHE-1 inhibitor survived the entire protocol. In control animals, cardiac output and MAP gradually decreased at each step of blood loss with marked increase in heart rate. Cardiovascular decompensation occurred at 40 mL kg(-1) blood loss. Na+/H+ exchange inhibition increased oxygen delivery, attenuated cardiovascular decompensation, delayed the onset of irreversible hypovolemic circulatory shock, and enabled resuscitation to survival. Echocardiography analysis showed that myocardial hypercontracture gradually developed with each step of blood loss in control animals, but this hypercontracture was attenuated in the animals receiving the NHE-1 inhibitor. We conclude that NHE-1 inhibition attenuates ischemic myocardial hypercontracture, cardiovascular decompensation, delays the onset of hypovolemic circulatory shock, and prevents early death in severe hemorrhage.

  16. Solving the Mechanism of Na+/H+ Antiporters Using Molecular Dynamics Simulations

    NASA Astrophysics Data System (ADS)

    Dotson, David L.

    Na+/H+ antiporters are vital membrane proteins for cell homeostasis, transporting Na+ ions in exchange for H+ across the lipid bilayer. In humans, dysfunction of these transporters are implicated in hypertension, heart failure, epilepsy, and autism, making them well-established drug targets. Although experimental structures for bacterial homologs of the human Na+/H+ have been obtained, the detailed mechanism for ion transport is still not well-understood. The most well-studied of these transporters, Escherichia coli NhaA, known to transport 2 H+ for every Na+ extruded, was recently shown to bind H+ and Na+ at the same binding site, for which the two ion species compete. Using molecular dynamics simulations, the work presented in this dissertation shows that Na+ binding disrupts a previously-unidentified salt bridge between two conserved residues, suggesting that one of these residues, Lys300, may participate directly in transport of H+. This work also demonstrates that the conformational change required for ion translocation in a homolog of NhaA, Thermus thermophilus NapA, thought by some to involve only small helical movements at the ion binding site, is a large-scale, rigid-body movement of the core domain relative to the dimerization domain. This elevator-like transport mechanism translates a bound Na+ up to 10 A across the membrane. These findings constitute a major shift in the prevailing thought on the mechanism of these transporters, and serve as an exciting launchpad for new developments toward understanding that mechanism in detail.

  17. Factors Influencing Expression of luxCDABE and nah Genes in Pseudomonas putida RB1353(NAH7, pUTK9) in Dynamic Systems

    PubMed Central

    Neilson, Julia W.; Pierce, Shelley A.; Maier, Raina M.

    1999-01-01

    Bioluminescent reporter organisms have been successfully exploited as analytical tools for in situ determination of bioavailable levels of contaminants in static environmental samples. Continued characterization and development of such reporter systems is needed to extend the application of these bioreporters to in situ monitoring of degradation in dynamic environmental systems. In this study, the naphthalene-degrading, lux bioreporter bacterium Pseudomonas putida RB1353 was used to evaluate the relative influences of cell growth stage, cell density, substrate concentration, oxygen tension, and background carbon substrates on both the magnitude of the light response and the rate of salicylate disappearance. The effect of these variables on the lag time required to obtain maximum luminescence and degradation was also monitored. Strong correlations were observed between the first three factors and both the magnitude and induction time of luminescence and degradation rate. The maximum luminescence response to nonspecific background carbon substrates (soil extract broth or Luria broth) was 50% lower than that generated in response to 1 mg of sodium salicylate liter−1. Oxygen tension was evaluated over the range of 0.5 to 40 mg liter−1, with parallel inhibition to luminescence and degradation rate (20 mg of sodium salicylate liter−1) observed at 1.5 mg liter−1 and below and no effect observed above 5 mg liter−1. Oxygen tensions from 2 to 4 mg liter−1 influenced the magnitude of luminescence but not the salicylate degradation rate. The results suggest that factors causing parallel shifts in the magnitude of both luminescence and degradation rate were influencing regulation of the nah operon promoters. For factors that cause nonparallel shifts, other regulatory mechanisms are explored. This study demonstrates that lux reporter bacteria can be used to monitor both substrate concentration and metabolic response in dynamic systems. However, each lux reporter

  18. Acoustic transducer for acoustic microscopy

    DOEpatents

    Khuri-Yakub, Butrus T.; Chou, Ching H.

    1990-01-01

    A shear acoustic transducer-lens system in which a shear polarized piezoelectric material excites shear polarized waves at one end of a buffer rod having a lens at the other end which excites longitudinal waves in a coupling medium by mode conversion at selected locations on the lens.

  19. Acoustic transducer for acoustic microscopy

    DOEpatents

    Khuri-Yakub, B.T.; Chou, C.H.

    1990-03-20

    A shear acoustic transducer-lens system is described in which a shear polarized piezoelectric material excites shear polarized waves at one end of a buffer rod having a lens at the other end which excites longitudinal waves in a coupling medium by mode conversion at selected locations on the lens. 9 figs.

  20. Depth resolution enhancement in double-detection optical scanning holography.

    PubMed

    Ou, Haiyan; Poon, Ting-Chung; Wong, Kenneth K Y; Lam, Edmund Y

    2013-05-01

    We propose an optical scanning holography system with enhanced axial resolution using two detections at different depths. By scanning the object twice, we can obtain two different sets of Fresnel zone plates to sample the same object, which in turn provides more information for the sectional image reconstruction process. We develop the computation algorithm that makes use of such information, solving a constrained optimization problem using the conjugate gradient method. Simulation results show that this method can achieve a depth resolution up to 1 μm.

  1. Full-field vibrometry with digital Fresnel holography

    SciTech Connect

    Leval, Julien; Picart, Pascal; Boileau, Jean Pierre; Pascal, Jean Claude

    2005-09-20

    A setup that permits full-field vibration amplitude and phase retrieval with digital Fresnel holography is presented. Full reconstruction of the vibration is achieved with a three-step stroboscopic holographic recording, and an extraction algorithm is proposed. The finite temporal width of the illuminating light is considered in an investigation of the distortion of the measured amplitude and phase. In particular, a theoretical analysis is proposed and compared with numerical simulations that show good agreement. Experimental results are presented for a loudspeaker under sinusoidal excitation; the mean quadratic velocity extracted from amplitude evaluation under two different measuring conditions is presented. Comparison with time averaging validates the full-field vibrometer.

  2. Electron holography for improved measurement of microfields in nanoelectrode assemblies

    SciTech Connect

    Chou, L.-J.; Chang, M.-T.; Chueh, Y.-L.; Kim, Joong Jung; Park, Hyun Soon; Shindo, Daisuke

    2006-07-10

    An approach to investigate the electric field distribution and field-emission property of a single crystal tungsten oxide (WO{sub 3}) nanowire by electron holography technique is presented, which solves the problems encountered in the traditional reconstruction of the holograms, the so-called perturbed reference wave. We proposed this unique method to meticulously illustrate the status of the surroundings of a single crystal nanowire under biased conditions. This paves the way to precisely quantifying the electric and magnetic field distributions for nanostructures as well as nanodevices.

  3. Soft x-ray holography and microscopy of biological cells

    NASA Astrophysics Data System (ADS)

    Chen, Jianwen; Gao, Hongyi; Xie, Honglan; Li, Ruxin; Xu, Zhizhan

    2003-10-01

    Some experimental results on soft X-ray microscopy and holography imaging of biological specimens are presented in the paper. As we know, due to diffraction effects, there exists a resolution limit determined by wavelength λ and numerical aperture NA in conventional optical microscopy. In order to improve resolution, the num erical aperture should be made as large as possible and the wavelength as short as possible. Owing to the shorter wavelength, X-rays provide the potential of higher resolution in X-ray microscopy, holography image and allow for exam ination the interior structures of thicker specimens. In the experiments, we used synchrotron radiation source in Hefei as light source. Soft X-rays come from a bending magnet in 800 M eV electron storage ring with characteristic wavelength of 2.4 nm. The continuous X-ray spectrums are monochromatized by a zone-plate and a pinhole with 300 m diameter. The experimental set-up is typical contact microscopic system, its main advantage is simplicity and no special optical element is needed. The specimens used in the experiments of microscopic imaging are the colibacillus, the gingko vascular hundle and the fritillaries ovary karyon. The specimen for holographic imaging is the spider filam ents. The basic structures of plant cells such as the cell walls, the cytoplasm and the karyon especially the joint structures between the cells are observed clearly. An experimental study on a thick biological specimen that is a whole sporule w ith the thickness of about 30 μm is performed. In the holographic experiments, the experimental setup is typical Gabor in-line holography. The specimen is placed in line with X-ray source, which provides both the reference w aves and specimen illum ination. The specimen is some spider filament, which adhere to a Si3N4 film. The recording medium is PM M A, which is placed at recording distance of about 400 μm from the specimen. The hologram s were reconstructed by digital method with 300 nm

  4. Detection of surface strain by three-dimensional digital holography

    NASA Astrophysics Data System (ADS)

    de La Torre-Ibarra, Manuel; Mendoza-Santoyo, Fernando; Pérez-López, Carlos; Saucedo-A., Tonatiuh

    2005-01-01

    Three-dimensional digital holography with three object-illuminating beams has been successfully used for the detection of surface strain in metallic objects. The optical setup that uses illuminating beams to irradiate the object from three directions means that all three object surface displacement components, x, y, and z, can be independently calculated and used to find the strain gradients on the surface. The results show the conversion of the complete surface displacement field into a surface strain field. The method is capable of measuring microstrains for out-of-plane surface displacements of less than 10 μm.

  5. Digital holography with a quadrature phase-shifting interferometer.

    PubMed

    Kiire, Tomohiro; Nakadate, Suezou; Shibuya, Masato

    2009-03-01

    An alternative method for digital holography using a quadrature phase-shifting interferometer for high-speed measurement is presented. We show that it has image quality equal to the four-bucket method. In addition, it requires fewer imaging devices. Two quadrature phase-shifting fringe patterns are acquired in each state of an object changed temporally. The phase calculation method with these four fringe patterns gives the phase distribution of the hologram. This digital phase hologram is reconstructed to yield an object image by the Fresnel transform using digital convolutions with the fast Fourier transform algorithm. Verification results of simulations and experiments are given.

  6. Parallel phase-shifting digital holography using spectral estimation technique.

    PubMed

    Xia, Peng; Awatsuji, Yasuhiro; Nishio, Kenzo; Ura, Shogo; Matoba, Osamu

    2014-09-20

    We propose a parallel phase-shifting digital holography using a spectral estimation technique, which enables the instantaneous acquisition of spectral information and three-dimensional (3D) information of a moving object. In this technique, an interference fringe image that contains six holograms with two phase shifts for three laser lines, such as red, green, and blue, is recorded by a space-division multiplexing method with single-shot exposure. The 3D monochrome images of these three laser lines are numerically reconstructed by a computer and used to estimate the spectral reflectance distribution of object using a spectral estimation technique. Preliminary experiments demonstrate the validity of the proposed technique.

  7. Solution to the Twin Image Problem in Holography

    SciTech Connect

    Latychevskaia, Tatiana; Fink, Hans-Werner

    2007-06-08

    While holography truly constitutes an ingenious concept, ever since its invention by Gabor it has been troubled by the so-called twin-image problem limiting the information that can be obtained from a holographic record. For symmetry reasons there are always two images appearing in the reconstruction of a hologram and the unwanted out of focus twin-image obscures the object. Here we show a universal method of reconstructing a hologram completely free of twin-image disturbances while no assumptions about absorbing or phase shifting properties of the object need to be imposed. Thus, truthful amplitude and phase distributions are retrieved.

  8. Fourier transform light scattering angular spectroscopy using digital inline holography.

    PubMed

    Kim, Kyoohyun; Park, YongKeun

    2012-10-01

    A simple and practical method for measuring the angle-resolved light scattering (ARLS) from individual objects is reported. Employing the principle of inline holography and a Fourier transform light scattering technique, both the static and dynamic scattering patterns from individual micrometer-sized objects can be effectively and quantitatively obtained. First, the light scattering measurements were performed on individual polystyrene beads, from which the refractive index and diameter of each bead were retrieved. Also, the measurements of the static and dynamic light scattering from intact human red blood cells are demonstrated. Using the present method, an existing microscope can be directly transformed into a precise instrument for ARLS measurements.

  9. Dynamic modal characterization of musical instruments using digital holography.

    PubMed

    Demoli, Nazif; Demoli, Ivan

    2005-06-27

    This study shows that a dynamic modal characterization of musical instruments with membrane can be carried out using a low-cost device and that the obtained very informative results can be presented as a movie. The proposed device is based on a digital holography technique using the quasi-Fourier configuration and time-average principle. Its practical realization with a commercial digital camera and large plane mirrors allows relatively simple analyzing of big vibration surfaces. The experimental measurements given for a percussion instrument are supported by the mathematical formulation of the problem.

  10. Biomechanical testing in experimental surgery by laser holography

    NASA Astrophysics Data System (ADS)

    Podbielska, Halina; Kasprzak, Henryk T.; Pennig, Dietmar

    1990-06-01

    Of all the capabilities of holography for image processing and measuring purposes, holographic interferometry has found the broadest application in biological and medical research. As a technique, which is non-destructive and allows for high resolving deformation analysis, holographic interferometry has gained popularity over the recent years in experimental biomechanics and orthopaedics. Some examples of holographic interferometry in experimental orthopaedics are reviewed in this report. The possibility of using holographic interferometry to study the behaviour of broken bones supported by fixing devices is pointed out in this review.

  11. Three-dimensional edge extraction in optical scanning holography

    NASA Astrophysics Data System (ADS)

    Zong, Yonghong; Zhou, Changhe; Ma, Jianyong; Jia, Wei; Wang, Jin

    2016-10-01

    Edge extraction has found applications in various image processing fields, such as in pattern recognition. In this paper, a new method is proposed for edge extraction of three-dimensional objects in optical scanning holography (OSH). Isotropic and anisotropic edge extraction of 3D objects is simulated using spiral phase plates in OSH operating in an incoherent mode. We propose to use a delta function and a spiral phase plate as the pupil functions to realize isotropic and anisotropic edge extraction. Our computer simulations show the capability of extracting the edges of a given 3D object by spiral phase filtering in OSH.

  12. Beamforming and holography image formation methods: an analytic study.

    PubMed

    Solimene, Raffaele; Cuccaro, Antonio; Ruvio, Giuseppe; Tapia, Daniel Flores; O'Halloran, Martin

    2016-04-18

    Beamforming and holographic imaging procedures are widely used in many applications such as radar sensing, sonar, and in the area of microwave medical imaging. Nevertheless, an analytical comparison of the methods has not been done. In this paper, the Point Spread Functions pertaining to the two methods are analytically determined. This allows a formal comparison of the two techniques, and to easily highlight how the performance depends on the configuration parameters, including frequency range, number of scatterers, and data discretization. It is demonstrated that the beamforming and holography basically achieve the same resolution but beamforming requires a cheaper (less sensors) configuration..

  13. On-line metrology with conoscopic holography: beyond triangulation.

    PubMed

    Alvarez, Ignacio; Enguita, Jose M; Frade, María; Marina, Jorge; Ojea, Guillermo

    2009-01-01

    On-line non-contact surface inspection with high precision is still an open problem. Laser triangulation techniques are the most common solution for this kind of systems, but there exist fundamental limitations to their applicability when high precisions, long standoffs or large apertures are needed, and when there are difficult operating conditions. Other methods are, in general, not applicable in hostile environments or inadequate for on-line measurement. In this paper we review the latest research in Conoscopic Holography, an interferometric technique that has been applied successfully in this kind of applications, ranging from submicrometric roughness measurements, to long standoff sensors for surface defect detection in steel at high temperatures.

  14. Direct inversion of digital 3D Fraunhofer holography maps.

    PubMed

    Podorov, Sergei G; Förster, Eckhart

    2016-01-20

    Differential Fourier holography (DFH) gives an exact mathematical solution of the inverse problem of diffraction in the Fraunhofer regime. After the first publication [Opt. Express15, 9954 (2007)], DFH was successfully applied in many experiments to obtain amplitude and phase information about two-dimensional images. In this paper, we demonstrate numerically the possibility to apply DFH also for investigation of unknown three-dimensional objects. The first simulation is made for a double-spiral structure plus a line as a reference object.

  15. Characterization of Magnetic Nanostructures Using Off-Axis Electron Holography

    NASA Astrophysics Data System (ADS)

    Zhang, Desai

    This dissertation research has involved microscopic characterization of magnetic nanostructures using off-axis electron holography and Lorentz microscopy. The nanostructures investigated have included Co nanoparticles (NPs), Au/Fe/GaAs shell/core nanowires (NWs), carbon spirals with magnetic cores, magnetic nanopillars, Ni-Zn-Co spinel ferrite and CoFe/Pd multilayers. The studies have confirmed the capability of holography to describe the behavior of magnetic structures at the nanoscale. The phase changes caused by the fringing fields of chains consisting of Co NPs were measured and calculated. The difference between chains with different numbers of Co NPs followed the trend indicated by calculations. Holography studies of Au/Fe/GaAs NWs grown on (110) GaAs substrates with rotationally non-uniform coating confirmed that Fe was present in the shell and that the shell behaved as a bar magnet. No fringing field was observed from NWs with cylindrical coating grown on (111)B GaAs substrates. The most likely explanation is that magnetic fields are confined within the shells and form closed loops. The multiple-magnetic-domain structure of iron carbide cores in carbon spirals was imaged using phase maps of the fringing fields. The strength and range of this fringing field was insufficient for manipulating the carbon spirals with an external applied magnetic field. No magnetism was revealed for CoPd/Fe/CoPd magnetic nanopillars. Degaussing and MFM scans ruled out the possibility that saturated magnetization and sample preparation had degraded the anisotropy, and the magnetism, respectively. The results suggested that these nanopillars were not suitable as candidates for prototypical bit information storage devices. Observations of Ni-Zn-Co spinel ferrite thin films in plan-view geometry indicated a multigrain magnetic domain structure and the magnetic fields were oriented in-plane only with no preferred magnetization distribution. This domain structure helps explain this

  16. Acoustic chaos

    SciTech Connect

    Lauterborn, W.; Parlitz, U.; Holzfuss, J.; Billo, A.; Akhatov, I.

    1996-06-01

    Acoustic cavitation, a complex, spatio-temporal dynamical system, is investigated with respect to its chaotic properties. The sound output, the {open_quote}{open_quote}noise{close_quote}{close_quote}, is subjected to time series analysis. The spatial dynamics of the bubble filaments is captured by high speed holographic cinematography and subsequent digital picture processing from the holograms. Theoretical models are put forward for describing the pattern formation. {copyright} {ital 1996 American Institute of Physics.}

  17. Medical Acoustics

    NASA Astrophysics Data System (ADS)

    Beach, Kirk W.; Dunmire, Barbrina

    Medical acoustics can be subdivided into diagnostics and therapy. Diagnostics are further separated into auditory and ultrasonic methods, and both employ low amplitudes. Therapy (excluding medical advice) uses ultrasound for heating, cooking, permeablizing, activating and fracturing tissues and structures within the body, usually at much higher amplitudes than in diagnostics. Because ultrasound is a wave, linear wave physics are generally applicable, but recently nonlinear effects have become more important, even in low-intensity diagnostic applications.

  18. Object recognition by use of polarimetric phase-shifting digital holography.

    PubMed

    Nomura, Takanori; Javidi, Bahram

    2007-08-01

    Pattern recognition by use of polarimetric phase-shifting digital holography is presented. Using holography, the amplitude distribution and phase difference distribution between two orthogonal polarizations of three-dimensional (3D) or two-dimensional phase objects are obtained. This information contains both complex amplitude and polarimetric characteristics of the object, and it can be used for improving the discrimination capability of object recognition. Experimental results are presented to demonstrate the idea. To the best of our knowledge, this is the first report on 3D polarimetric recognition of objects using digital holography.

  19. The application of holography as a real-time three-dimensional motion picture camera

    NASA Technical Reports Server (NTRS)

    Kurtz, R. L.

    1973-01-01

    A historical introduction to holography is presented, as well as a basic description of sideband holography for stationary objects. A brief theoretical development of both time-dependent and time-independent holography is also provided, along with an analytical and intuitive discussion of a unique holographic arrangement which allows the resolution of front surface detail from an object moving at high speeds. As an application of such a system, a real-time three-dimensional motion picture camera system is discussed and the results of a recent demonstration of the world's first true three-dimensional motion picture are given.

  20. Acoustic dose and acoustic dose-rate.

    PubMed

    Duck, Francis

    2009-10-01

    Acoustic dose is defined as the energy deposited by absorption of an acoustic wave per unit mass of the medium supporting the wave. Expressions for acoustic dose and acoustic dose-rate are given for plane-wave conditions, including temporal and frequency dependencies of energy deposition. The relationship between the acoustic dose-rate and the resulting temperature increase is explored, as is the relationship between acoustic dose-rate and radiation force. Energy transfer from the wave to the medium by means of acoustic cavitation is considered, and an approach is proposed in principle that could allow cavitation to be included within the proposed definitions of acoustic dose and acoustic dose-rate.

  1. The implementation of holography in the plane wave matrix model

    NASA Astrophysics Data System (ADS)

    Mints, Aleksey Leonidovich

    It is expected that at the core of nonperturbative theories of quantum gravity, such as M-theory, lies the realization of the holographic principle, in the sense that a holographic theory should contain one binary degree of freedom per Planck area. Present understanding of such theories requires the holographic encoding of bulk data in large matrices. Currently this mapping is poorly understood. The plane wave matrix model provides a laboratory for isolating aspects of this problem in a controlled setting. At large boosts, configurations of concentric membranes become superselection sectors, whose exact spectra are known. From the bulk point of view one expects product states of individual membranes to be contained within the full spectrum. However, for non-BPS states this inclusion relation is obscured by Gauss law constraints. Its validity rests on nontrivial relations in representation theory, which we identify and verify by explicit computation. Beyond the decoding and partial identification of selected states in large matrices, one would like to get a better understanding of the holographic state counting of these degrees of freedom, i.e., entropy. Contrary to the naive expectation of holography realized in terms of the covariant entropy bound, we present evidence that it is the Bekenstein entropy bound, which is related to area differences, that is manifest in the plane wave matrix model. If holography is implemented in this way, we predict crossover behavior at strong coupling when the energy exceeds N2 in units of the mass scale.

  2. Automated fringe analysis in diffusivity measurements by sandwich holography

    NASA Astrophysics Data System (ADS)

    Paoletti, Domenica; Schirripa Spagnolo, Giuseppe; Laurenti, Lucio; Ponticiello, Antonio

    1992-09-01

    An image processing system to analyze interference patterns, related to the measurement of diffusion coefficient of liquid binary mixtures by sandwich holography, is proposed. Basic image processing tools are used and a specific software has been developed to perform an automated analysis of interferometric data. An example of application of this electrooptical method to the measurement of the diffusion coefficient of LiBr is reported. On propose un système de traitement d'images pour analyser des modèles d'interférence par rapport à la mesure du coefficient de diffusion des mélanges liquides binaires, obtenue suivant la technique de l'holographie sandwich. Les appareils et les outils utilisés sont standard tandis que le logiciel spécifique pour l'analyse automatique des données interférométriques acquises a été développé ad hoc. Un exemple d'application de cette méthode électro-optique a regardé la mesure du coefficient de diffusion du LiBr.

  3. Fresnel incoherent correlation holography and its imaging properties

    NASA Astrophysics Data System (ADS)

    Wang, Zhipeng; Ma, Haotong; Ren, Ge; Xie, Zongliang; Yu, Huan

    2016-09-01

    The incoherent digital holography makes it possible to record holograms under incoherent illumination, which lowers requirement for the coherence of light sources and results in expanding its application to white-light and fluorescence illuminating circumstances. The Fresnel Incoherent Correlation Holography (FINCH) technology achieves diverging the incident beam and shifting phase by mounting phase masks on the phase modulator. Then it obtains holograms with phase difference and reconstructs the image. In this paper, we explain the principles of the FINCH technology, and introduce the n-step phase-shifting method which is utilized to eliminate the twin image and bias term in holograms. During the research, we studied what impact the term n may have on imaging performance, compared imaging performances when different phase masks are mounted on SLM, and established simulation system on imaging with which imaging performances are deeply inspected. At last, it is shown in the research that the FINCH technology could record holograms of objects, from which clear images could be reconstructed digitally.

  4. 25 Years Of Holography The Development Of Holographic Testing

    NASA Astrophysics Data System (ADS)

    Rottenkolber, H.

    1988-06-01

    It was of course Dennis Gabor who, as long ago as 1948, published the fundamental work the principle of holography. But it was not until Theodore Maiman's invention of the laser in 1960 that the practical realisation of holography became possible. This was achieved by Leith and Upatnicks between 1962 and 1964, with the crucial impetus being provided by Vander Lugt (the author wishes to acknowledge the assistence of A. Vander Lugt, who, while performing work of a relatet nature, showed him the value of the gas laser as a light source). 1964 was the year in which Denisyuk presented his first portrait holograms in Leningrad. The many publications of Stroke of the University of New York were a source of numerous impulses. It is to this period, too, that my own first experiences date back. Together with my teacher. Ulrich Grigull, whom I hold in the highest regard, I constructed the first laser interferometer for the study of heat transfer and developed the initial ideas for holo-graphic interferometry. Then, in 1965, came the work of Hildebrandt and Haines and of Powell and Stetson in the United States in this field, and it was around this time, too, that Nassenstein and his colleagues Riek and Bestenreiner began their work in this new area in Germany.

  5. Spatial-temporal demodulation technique for heterodyne optical scanning holography

    NASA Astrophysics Data System (ADS)

    Liu, Jung-Ping; Luo, Dao-Zheng; Lu, Sheng-Hua

    2015-05-01

    In optical scanning holography (OSH), the object is raster scanned by a heterodyne fringe pattern. The light scattered from the object is detected by a photodetector. Traditionally, the photo-electric signal is demodulated by a dual-channel lock-in amplifier (LIA) to extract a complex hologram. The use of LIA complicates the detection module of the system and increases the cost, especially when the heterodyne frequency is high. In this paper, an alternative demodulation method called a spatial-temporal demodulation technique (STDT) is studied. In STDT, the photo-electric temporal signal is directly digitized as scanning lines. The spectrum of each scanning line is band-pass filtered to remove the zeroth-order term and the complex conjugate term. Finally, a complex hologram is obtained from the filtered spectrum. The first merit of STDT is that the phase of the demodulated complex hologram is insensitive to the modulation error. Thus it is easily applied to the applications of particle holography. Besides, the bandwidth of the zeroth-order term in STDT is narrow, which allows the system to be operated in a wide range of heterodyne frequency. This feature enables STDT-based OSH to be applied in low-cost and high-speed dynamic holographic imaging.

  6. Ultra wide band 3-D cross section (RCS) holography

    NASA Astrophysics Data System (ADS)

    Collins, H. D.; Hall, T. E.

    1992-07-01

    Ultra wide band impulse holography is an exciting new concept for predictive radar cross section (RCS) evaluation employing near-field measurements. Reconstruction of the near-field hologram data maps the target's scattering areas, and uniquely identifies the 'hot spot' locations on the target. In addition, the target and calibration sphere's plane wave angular spectrums are computed (via digital algorithm) and used to generate the target's far-field RCS values in three dimensions for each frequency component in the impulse. Thin and thick targets are defined in terms of their near-field amplitude variations in range. Range gating and computer holographic techniques are applied to correct these variations. Preliminary experimental results on various targets verify the concept of RCS holography. The unique 3-D presentation (i.e., typically containing 524,288 RCS values for a 1024 (times) 512 sampled aperture for every frequency component) illustrates the efficacy of target recognition in terms of its far-field plane wave angular spectrum image. RCS images can then be viewed at different angles for target recognition, etc.

  7. Ultra wide band 3-D cross section (RCS) holography

    SciTech Connect

    Collins, H.D.; Hall, T.E.

    1992-07-01

    Ultra wide band impulse holography is an exciting new concept for predictive radar cross section (RCS) evaluation employing near-field measurements. Reconstruction of the near-field hologram data maps the target's scattering areas, and uniquely identifies the hot spot'' locations on the target. In addition, the target and calibration sphere's plane wave angular spectrums are computed (via digital algorithm) and used to generate the target's far-field RCS values in three dimensions for each frequency component in the impulse. Thin and thick targets are defined in terms of their near-field amplitude variations in range. Range gating and computer holographic techniques are applied to correct these variations. Preliminary experimental results on various targets verify the concept of RCS holography. The unique 3-D presentation (i.e., typically containing 524,288 RCS values for a 1024 {times} 512 sampled aperture for every frequency component) illustrates the efficacy of target recognition in terms of its far-field plane wave angular spectrum image. RCS images can then be viewed at different angles for target recognition, etc.

  8. Ultra wide band 3-D cross section (RCS) holography

    SciTech Connect

    Collins, H.D.; Hall, T.E.

    1992-07-01

    Ultra wide band impulse holography is an exciting new concept for predictive radar cross section (RCS) evaluation employing near-field measurements. Reconstruction of the near-field hologram data maps the target`s scattering areas, and uniquely identifies the ``hot spot`` locations on the target. In addition, the target and calibration sphere`s plane wave angular spectrums are computed (via digital algorithm) and used to generate the target`s far-field RCS values in three dimensions for each frequency component in the impulse. Thin and thick targets are defined in terms of their near-field amplitude variations in range. Range gating and computer holographic techniques are applied to correct these variations. Preliminary experimental results on various targets verify the concept of RCS holography. The unique 3-D presentation (i.e., typically containing 524,288 RCS values for a 1024 {times} 512 sampled aperture for every frequency component) illustrates the efficacy of target recognition in terms of its far-field plane wave angular spectrum image. RCS images can then be viewed at different angles for target recognition, etc.

  9. Acoustic Tooth Cleaner

    NASA Technical Reports Server (NTRS)

    Heyman, J. S.

    1984-01-01

    Acoustically-energized water jet aids in plaque breakdown. Acoustic Wand includes acoustic transducer 1/4 wave plate, and tapered cone. Together elements energize solution of water containing mild abrasive injected into mouth to help prevent calculous buildup.

  10. Holography: Use in Training and Testing Drivers on the Road in Accident Avoidance.

    ERIC Educational Resources Information Center

    Frey, Allan H.; Frey, Donnalyn

    1979-01-01

    Defines holography, identifies visual factors in driving and the techniques used in on-road visual presentations, and presents the design and testing of a holographic system for driver training. (RAO)

  11. Joint Applied Optics and Chinese Optics Letters feature introduction: digital holography and three-dimensional imaging.

    PubMed

    Poon, Ting-Chung

    2011-12-01

    This feature issue serves as a pilot issue promoting the joint issue of Applied Optics and Chinese Optics Letters. It focuses upon topics of current relevance to the community working in the area of digital holography and 3-D imaging.

  12. Holography and Colliding gravitational shock waves in asymptotically AdS5 spacetime.

    PubMed

    Chesler, Paul M; Yaffe, Laurence G

    2011-01-14

    Using holography, we study the collision of planar shock waves in strongly coupled N=4 supersymmetric Yang-Mills theory. This requires the numerical solution of a dual gravitational initial value problem in asymptotically anti-de Sitter spacetime.

  13. Direct volume access by an improved electro-holography image generator

    NASA Astrophysics Data System (ADS)

    Takahashi, Hideya; Tanaka, Kazuyuki; Okamoto, Hideki; Ueda, Hiroaki; Shimizu, Eiji

    1995-04-01

    A CAD system with electronic holography is expected to provide ideal designing environments to feel and touch truly 3D images directly. However, interactivity and real-time computation of holographic fringe patterns are the essential requirements to realize it. This paper presents two different types of 3D images creating system. One consists of a 3D pointing device and an electro-holography system with an acousto-optical modulator which was proposed by Prof. Benton in 1989. The other consists of a 3D pointing device and an electro-holography system with a liquid crystal device. We also propose an effective method not depending on the total number of points in the scene and apply it to the designing tool by only appending points in a electro-holography system with a 3D input device.

  14. Enhanced V-ATPase activity contributes to the improved salt tolerance of transgenic tobacco plants overexpressing vacuolar Na(+)/H (+) antiporter AtNHX1.

    PubMed

    Zhou, Shufeng; Zhang, Zhiming; Tang, Qilin; Lan, Hai; Li, Yinxin; Luo, Ping

    2011-02-01

    AtNHX1, a vacuolar Na(+)/H(+) antiporter gene from Arabidopsis thaliana, was introduced into tobacco genome via Agrobacterium tumefaciens-mediated transformation to evaluate the role of vacuolar energy providers in plants salt stress response. Compared to the wild-type plants, over-expression of AtNHX1 increased salt tolerance in the transgenic tobacco plants, allowing higher germination rates of seeds and successful seedling establishment in the presence of toxic concentrations of NaCl. More importantly, the induced Na(+)/H(+) exchange activity in the transgenic plants was closely correlated to the enhanced activity of vacuolar H(+)-ATPase (V-ATPase) when exposed to 200 mM NaCl. In addition, inhibition of V-ATPase activity led to the malfunction of Na(+)/H(+) exchange activity, placing V-ATPase as the dominant energy provider for the vacuolar Na(+)/H(+) antiporter AtNHX1. V-ATPase and vacuolar Na(+)/H(+) antiporter thus function in an additive or synergistic way. Simultaneous overexpression of V-ATPase and vacuolar Na(+)/H(+) antiporter might be appropriate for producing plants with a higher salt tolerance ability.

  15. Effect of root-derived substrates on the expression of nah-lux genes in Pseudomonas fluorescens HK44: implications for PAH biodegradation in the rhizosphere.

    PubMed

    Kamath, Roopa; Schnoor, Jerald L; Alvarez, Pedro J J

    2004-03-15

    The bioluminescent reporter strain Pseudomonas fluorescens HK44 with a nah-lux fusion, was used to investigate the effect of root material (from hybrid poplars, willow, kou, milo, Osage orange, mulberry, and switch grass) and potential root-derived substrates (e.g., sugars, carboxylic acids, amino acids, and phenolics) on the expression of nahG, one of the genes responsible for naphthalene dioxygenase transcription. Whereas nahG was induced by some phenolic substrates that could be released by plants (i.e., salicylate, methyl salicylate, and acetyl salicylate), no induction by root extracts was observed. Rather, increasing root extract concentrations (50 to 275 mg L(-1) as total organic carbon) inhibited nahG expression in assays with cells concurrently exposed to naphthalene. Root extracts also decreased nahG expression at the individual cell level during naphthalene degradation assays. However, treatments with root extracts exhibited significantly higher microbial growth and overall bioluminescence, indicating a higher level of nahG expression by the resulting larger microbial population. This generally resulted in faster naphthalene degradation rates, suggesting that plant-promoted proliferation of competent genotypes could compensate for the interference that labile substrates exert on the expression of genes that code for the degradation of polynuclear aromatic hydrocarbons (PAHs). This could explain the faster PAH degradation commonly reported in planted than in unplanted soils.

  16. Functional analysis of amino acid residues essential for activity in the Na+/H+ exchanger of fission yeast.

    PubMed

    Dibrov, P; Young, P G; Fliegel, L

    1998-06-09

    We identified amino acid residues important for activity of sod2, the Na+/H+ antiporter of Schizosaccharomyces pombe. We mutated all eight His residues of sod2 into Arg. Only His367-->Arg affected function and resulted in complete inability of sod2 to allow growth of S. pombe in LiCl-containing medium. Mutant S. pombe (H367R) could not expel sodium in acidic (pH 4.0) medium and were defective in their ability to alkalinize external medium. When His367 was replaced by Asp, sodium export of S. pombe was suppressed at acidic pH while the sodium-dependent proton influx at pH 6.1 was increased compared to wild type. We also mutated three residues conserved in putative membrane regions of various eukaryotic and prokaryotic Na+/H+ exchangers. S. pombe containing Asp241-->Asn and Asp266, 267-->Asn mutations had greatly impaired growth in LiCl-containing medium. In addition, sodium-dependent proton influx at external pH 6. 1 was impaired. Sodium export from S. pombe cells at external pH 4.0 was also almost completely abolished by the D266,267N mutation; however, the D241N mutant protein retained almost normal Na+ export. The results demonstrate that His367, Asp241, and Asp266,267 are important in the function of the eukaryotic Na+/H+ exchanger sod2.

  17. A New Approach for Three-Dimensional Atomic Imaging: Differential photoelectron holography

    NASA Astrophysics Data System (ADS)

    Omori, S.; Marchesini, S.; Nihei, Y.; Rotenberg, E.; Denlinger, J. D.; Kevan, S. D.; Tonner, B. P.; van Hove, M. A.; Fadley, Charles S.

    2002-03-01

    We propose differential holography as a method to overcome the long-standing forward-scattering problem in photoelectron holography and related techniques for the three-dimensional imaging of atoms. Atomic images reconstructed from experimental and theoretical Cu 3p holograms from Cu(001) demonstrate that this method suppresses strong forward-scattering effects so as to yield more accurate three-dimensional images of side- and back-scattering atoms.

  18. Differential Photoelectron Holography: A New Approach for Three-Dimensional Atomic Imaging

    NASA Astrophysics Data System (ADS)

    Omori, S.; Nihei, Y.; Rotenberg, E.; Denlinger, J. D.; Marchesini, S.; Kevan, S. D.; Tonner, B. P.; van Hove, M. A.; Fadley, C. S.

    2002-02-01

    We propose differential holography as a method to overcome the long-standing forward-scattering problem in photoelectron holography and related techniques for the three-dimensional imaging of atoms. Atomic images reconstructed from experimental and theoretical Cu 3p holograms from Cu(001) demonstrate that this method suppresses strong forward-scattering effects so as to yield more accurate three-dimensional images of side- and backscattering atoms.

  19. Parallel phase-shifting digital holography with adaptive function using phase-mode spatial light modulator.

    PubMed

    Lin, Miao; Nitta, Kouichi; Matoba, Osamu; Awatsuji, Yasuhiro

    2012-05-10

    Parallel phase-shifting digital holography using a phase-mode spatial light modulator (SLM) is proposed. The phase-mode SLM implements spatial distribution of phase retardation required in the parallel phase-shifting digital holography. This SLM can also compensate dynamically the phase distortion caused by optical elements such as beam splitters, lenses, and air fluctuation. Experimental demonstration using a static object is presented.

  20. Full-Field Imaging of Acoustic Motion at Nanosecond Time and Micron Length Scales

    SciTech Connect

    Telschow, Kenneth Louis; Deason, Vance Albert; Cottle, David Lynn; Larson III, John D.

    2002-10-01

    A full-field view laser ultrasonic imaging method has been developed that measures acoustic motion at a surface without scanning. Images are recorded at normal video frame rates by employing dynamic holography using photorefractive interferometric detection. By extending the approach to ultra high frequencies, an acoustic microscope has been developed capable of operation on the nanosecond time and micron length scales. Both acoustic amplitude and phase are recorded allowing full calibration and determination of phases to within a single arbitrary constant. Results are presented of measurements at frequencies at 800-900 MHz illustrating a multitude of normal mode behavior in electrically driven thin film acoustic resonators. Coupled with microwave electrical impedance measurements, this imaging mode provides an exceptionally fast method for evaluation of electric to acoustic coupling and performance of these devices. Images of 256x240 pixels are recorded at 18Hz rates synchronized to obtain both in-phase and quadrature detection of the acoustic motion. Simple averaging provides sensitivity to the subnanometer level calibrated over the image using interferometry. Identification of specific acoustic modes and their relationship to electrical impedance characteristics show the advantages and overall high speed of the technique.

  1. Stimulation of Na+/H+ Exchanger Isoform 1 Promotes Microglial Migration

    PubMed Central

    Shi, Yejie; Yuan, Hui; Kim, Dong; Chanana, Vishal; Baba, Akemichi; Matsuda, Toshio; Cengiz, Pelin; Ferrazzano, Peter; Sun, Dandan

    2013-01-01

    Regulation of microglial migration is not well understood. In this study, we proposed that Na+/H+ exchanger isoform 1 (NHE-1) is important in microglial migration. NHE-1 protein was co-localized with cytoskeletal protein ezrin in lamellipodia of microglia and maintained its more alkaline intracellular pH (pHi). Chemoattractant bradykinin (BK) stimulated microglial migration by increasing lamellipodial area and protrusion rate, but reducing lamellipodial persistence time. Interestingly, blocking NHE-1 activity with its potent inhibitor HOE 642 not only acidified microglia, abolished the BK-triggered dynamic changes of lamellipodia, but also reduced microglial motility and microchemotaxis in response to BK. In addition, NHE-1 activation resulted in intracellular Na+ loading as well as intracellular Ca2+ elevation mediated by stimulating reverse mode operation of Na+/Ca2+ exchange (NCXrev). Taken together, our study shows that NHE-1 protein is abundantly expressed in microglial lamellipodia and maintains alkaline pHi in response to BK stimulation. In addition, NHE-1 and NCXrev play a concerted role in BK-induced microglial migration via Na+ and Ca2+ signaling. PMID:23991215

  2. Purification and Functional Reconstitution of a Seven-Subunit Mrp-Type Na+/H+ Antiporter

    PubMed Central

    Morino, Masato; Suzuki, Toshiharu; Ito, Masahiro

    2014-01-01

    Mrp antiporters and their homologues in the cation/proton antiporter 3 family of the Membrane Transporter Database are widely distributed in bacteria. They have major roles in supporting cation and cytoplasmic pH homeostasis in many environmental, extremophilic, and pathogenic bacteria. These antiporters require six or seven hydrophobic proteins that form hetero-oligomeric complexes, while most other cation/proton antiporters require only one membrane protein for their activity. The resemblance of three Mrp subunits to membrane-embedded subunits of the NADH:quinone oxidoreductase of respiratory chains and to subunits of several hydrogenases has raised interest in the evolutionary path and commonalities of their proton-translocating domains. In order to move toward a greater mechanistic understanding of these unusual antiporters and to rigorously demonstrate that they function as secondary antiporters, powered by an imposed proton motive force, we established a method for purification and functional reconstitution of the seven-subunit Mrp antiporter from alkaliphilic Bacillus pseudofirmus OF4. Na+/H+ antiporter activity was demonstrated by a fluorescence-based assay with proteoliposomes in which the Mrp complex was coreconstituted with a bacterial FoF1-ATPase. Proton pumping by the ATPase upon addition of ATP generated a proton motive force across the membranes that powered antiporter activity upon subsequent addition of Na+. PMID:24142251

  3. Myocardial Na+/H+ exchanger-1 (NHE1) content is decreased by exercise training.

    PubMed

    Feger, Bryan J; Starnes, Joseph W

    2013-06-01

    The effect of exercise training on myocardial Na(+)/H(+) exchanger-1 (NHE1) protein expression was examined. Adult female Sprague-Dawley rats were randomly divided into sedentary (S; n = 8) and exercised (E; n = 9) groups. Twenty-four hours after the last exercise bout, hearts were weighed and connected to an isolated perfused working heart apparatus for evaluation of cardiac functional performance. Heart weight and heart weight/body weight from E rats was significantly increased by 7.1 and 7.2 % (P < 0.05), respectively, compared with S hearts. The E hearts displayed 15 % greater cardiac output and 35 % external cardiac work compared with the S group at both low and high workloads (P < 0.05 for both parameters). Left ventricular tissue from the same hearts was homogenized and NHE1 and Na(+)/Ca(2+) exchanger (NCX) content determined by Western blotting. E hearts had a 38 % (P < 0.001) reduction in NHE1 content related to S hearts, and there was no difference in NCX content between groups. Cytochrome c oxidase activity in plantaris increased by 100 % (P < 0.05) and was assessed as a marker of mitochondria content and to verify training status. Our data indicate that exercise training at an intensity that results in cardiac hypertrophy and improved performance is accompanied by decreased NHE1 content in heart.

  4. Regulation of the Na+/H+ Exchanger (NHE1) in Breast Cancer Metastasis.

    PubMed

    Amith, Schammim R; Fliegel, Larry

    2013-02-15

    The pH gradient in normal cells is tightly controlled by the activity of various pH-regulatory membrane proteins including the isoform protein of the Na(+)/H(+) exchanger (NHE1). NHE1 is constitutively active in a neoplastic microenvironment, dysregulating pH homeostasis and altering the survival, differentiation, and proliferation of cancer cells, thereby causing them to become tumorigenic. Cytoplasmic alkalinization in breast cancer cells occurs as a result of increased NHE1 activity and, while much is known about the pathophysiologic role of NHE1 in tumor progression with regard to ion flux, the regulation of its activity on a molecular level is only recently becoming evident. The membrane domain of NHE1 is sufficient for ion exchange. However, its activity is regulated through the phosphorylation of key amino acids in the cytosolic domain as well as by its interaction with other intracellular proteins and lipids. Here, we review the importance of these regulatory sites and what role they may play in the disrupted functionality of NHE1 in breast cancer metastasis.

  5. Thyroid hormone stimulates the renal Na/H exchanger NHE3 by transcriptional activation

    PubMed Central

    CANO, ADRIANA; BAUM, MICHEL; MOE, ORSON W.

    2014-01-01

    Thyroid hormone stimulates renal proximal tubule NaCl and NaHCO3 absorption in part by activating the apical membrane Na/H exchanger NHE3. We used a renal epithelial cell line, the opossum kidney (OK) cell, to define the mechanism by which 3,5,3′-triiodothyronine (T3) increases NHE3 activity. T3 stimulated NHE3 activity, an effect that was blocked by inhibition of cellular transcription or translation. The increase in activity was associated with increases in steady-state cell surface and total cellular NHE3 protein and NHE3 transcript abundance. T3 stimulated transcription of the NHE3 gene and had no effect on NHE3 transcript stability. The transcriptional activity of the 5′-flanking region of the rat NHE3 gene was stimulated by T3 when expressed in OK cells. When heterologously expressed rat NHE3 transcript levels were clamped constant with a constitutive promoter in OK cells, T3 has no effect on rat NHE3 protein abundance, suggesting the absence of regulation of NHE3 protein stability or translation. These studies demonstrate that T3 stimulates NHE3 activity by activating NHE3 gene transcription and increasing NHE3 transcript and protein abundance. PMID:9886925

  6. Purification and functional reconstitution of a seven-subunit mrp-type na+/h+ antiporter.

    PubMed

    Morino, Masato; Suzuki, Toshiharu; Ito, Masahiro; Krulwich, Terry Ann

    2014-01-01

    Mrp antiporters and their homologues in the cation/proton antiporter 3 family of the Membrane Transporter Database are widely distributed in bacteria. They have major roles in supporting cation and cytoplasmic pH homeostasis in many environmental, extremophilic, and pathogenic bacteria. These antiporters require six or seven hydrophobic proteins that form hetero-oligomeric complexes, while most other cation/proton antiporters require only one membrane protein for their activity. The resemblance of three Mrp subunits to membrane-embedded subunits of the NADH:quinone oxidoreductase of respiratory chains and to subunits of several hydrogenases has raised interest in the evolutionary path and commonalities of their proton-translocating domains. In order to move toward a greater mechanistic understanding of these unusual antiporters and to rigorously demonstrate that they function as secondary antiporters, powered by an imposed proton motive force, we established a method for purification and functional reconstitution of the seven-subunit Mrp antiporter from alkaliphilic Bacillus pseudofirmus OF4. Na(+)/H(+) antiporter activity was demonstrated by a fluorescence-based assay with proteoliposomes in which the Mrp complex was coreconstituted with a bacterial FoF1-ATPase. Proton pumping by the ATPase upon addition of ATP generated a proton motive force across the membranes that powered antiporter activity upon subsequent addition of Na(+).

  7. Cardiovascular effects of NA+/H+ exchanger inhibition with BIIB513 following hypovolemic circulatory shock.

    PubMed

    Wu, Dongmei; Bassuk, Jorge; Arias, Jaqueline; Doods, Henri; Adams, Jose A

    2005-03-01

    Na(+)/H(+) exchange (NHE) is involved in the myocardial injury that occurs during ischemia and reperfusion. The goal of the present study was to investigate the role of NHE in hypovolemic circulatory shock by using a potent NHE-1 selective inhibitor BIIB513. Acute rapid hemorrhage was induced in 14 pigs by bleeding (30 mL/kg over 30 min). Seven pigs were used as saline control. Seven other pigs received 3 mg/kg BIIB513 at 30 min after hemorrhage. Each experiment consisted of 2 h of hypovolemia followed by 2 h of fluid resuscitation. One control animal died before the experiment was completed. Six other control animals survived the entire experiment. In contrast, all the BIIB513 treated animals survived the entire protocol. Acute rapid blood loss resulted in impaired myocardial performance as well as severe hemodynamic and metabolic alterations. NHE blockade attenuated the hypovolemic hypotension and improved myocardial performance. NHE blockade also attenuated the metabolic acidosis, improved tissue oxygen delivery, and improved cardiac function from resuscitation. The circulating levels of creatine phosphokinase (CPK) and cardiac troponin-I were significantly lower in the BIIB513 treatment group. These results suggest that NHE activation plays an important pathophysiological role in hypovolemic circulatory shock, and NHE-1 blockade is a powerful intervention to improve cardiovascular outcomes of resuscitation from prolonged hypovolemic circulatory shock.

  8. Na+/H+ exchangers: physiology and link to hypertension and organ ischemia

    PubMed Central

    Bobulescu, I. Alexandru; Di Sole, Francesca; Moe, Orson W.

    2010-01-01

    Purpose of review Na+/H+ exchangers (NHEs) are ubiquitous proteins with a very wide array of physiological functions, which are summarized here with an emphasis on the most recent advances. Hypertension and organ ischemia are two disease states of paramount importance in which NHEs have been implicated. The involvement of NHEs in the pathophysiology of these disorders is incompletely understood. This paper reviews the principal findings and current hypotheses linking NHE dysfunction to hypertension and ischemia. Recent findings With the advent of large-scale sequencing projects and powerful in-silico analyses, we have come to know what is most likely the entire mammalian NHE gene family. Recent advances have detailed the roles of NHE proteins, exploring new functions such as anchoring, scaffolding and pH regulation of intracellular compartments. Studies of NHEs in disease models, though not conclusive to date, have contributed new evidence on the interplay of ion transporters and the delicate ion balances that may become disrupted. Summary This review provides the interested reader with a concise overview of NHE physiology, and addresses the implication of NHEs in the pathophysiology of hypertension and organ ischemia in light of the most recent literature. PMID:16046909

  9. Endosomal Na+/H+ exchanger NHE5 influences MET recycling and cell migration

    PubMed Central

    Fan, Steven Hung-Yi; Numata, Yuka; Numata, Masayuki

    2016-01-01

    Increased recycling and elevated cell surface expression of receptors serve as a mechanism for persistent receptor-mediated signaling. We show that the neuron-enriched Na+/H+ exchanger NHE5 is abundantly expressed in C6 glioma cells and plays an important part in regulating cell surface expression of the receptor tyrosine kinases MET and EGF receptor. NHE5 is associated with transferrin receptor (TfR)- and Rab11-positive recycling endosomal membranes, and NHE5 knockdown by short hairpin RNA significantly elevates pH of TfR-positive recycling endosomes. We present evidence that NHE5 facilitates MET recycling to the plasma membrane, protects MET from degradation, and modulates HGF-induced phosphatidylinositol-3-kinase and mitogen-activated protein kinase signaling. Moreover, NHE5 depletion abrogates Rac1 and Cdc42 signaling and actin cytoskeletal remodeling. We further show that NHE5 knockdown impairs directed cell migration and causes loss of cell polarity. Our study highlights a possible role of recycling endosomal pH in regulating receptor-mediated signaling through vesicular trafficking. PMID:26700318

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

    NASA Astrophysics Data System (ADS)

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

    2012-03-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2011-11-01

    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.

  12. Acoustic iridescence.

    PubMed

    Cox, Trevor J

    2011-03-01

    An investigation has been undertaken into acoustic iridescence, exploring how a device can be constructed which alter sound waves, in a similar way to structures in nature that act on light to produce optical iridescence. The main construction had many thin perforated sheets spaced half a wavelength apart for a specified design frequency. The sheets create the necessary impedance discontinuities to create backscattered waves, which then interfere to create strongly reflected sound at certain frequencies. Predictions and measurements show a set of harmonics, evenly spaced in frequency, for which sound is reflected strongly. And the frequency of these harmonics increases as the angle of observation gets larger, mimicking the iridescence seen in natural optical systems. Similar to optical systems, the reflections become weaker for oblique angles of reflection. A second construction was briefly examined which exploited a metamaterial made from elements and inclusions which were much smaller than the wavelength. Boundary element method predictions confirmed the potential for creating acoustic iridescence from layers of such a material.

  13. Acoustic transducer

    DOEpatents

    Drumheller, D.S.

    1997-12-30

    An acoustic transducer is described comprising a one-piece hollow mandrel into the outer surface of which is formed a recess with sides perpendicular to the central axis of the mandrel and separated by a first distance and with a bottom parallel to the central axis and within which recess are a plurality of washer-shaped discs of a piezoelectric material and at least one disc of a temperature-compensating material with the discs being captured between the sides of the recess in a pre-stressed interference fit, typically at 2,000 psi of compressive stress. The transducer also includes a power supply and means to connect to a measurement device. The transducer is intended to be used for telemetry between a measurement device located downhole in an oil or gas well and the surface. The transducer is of an construction that is stronger with fewer joints that could leak fluids into the recess holding the piezoelectric elements than is found in previous acoustic transducers. 4 figs.

  14. Acoustic transducer

    DOEpatents

    Drumheller, Douglas S.

    1997-01-01

    An acoustic transducer comprising a one-piece hollow mandrel into the outer surface of which is formed a recess with sides perpendicular to the central axis of the mandrel and separated by a first distance and with a bottom parallel to the central axis and within which recess are a plurality of washer-shaped discs of a piezoelectric material and at least one disc of a temperature-compensating material with the discs being captured between the sides of the recess in a pre-stressed interference fit, typically at 2000 psi of compressive stress. The transducer also includes a power supply and means to connect to a measurement device. The transducer is intended to be used for telemetry between a measurement device located downhole in an oil or gas well and the surface. The transducer is of an construction that is stronger with fewer joints that could leak fluids into the recess holding the piezoelectric elements than is found in previous acoustic transducers.

  15. Development and calibration of acoustic video camera system for moving vehicles

    NASA Astrophysics Data System (ADS)

    Yang, Diange; Wang, Ziteng; Li, Bing; Lian, Xiaomin

    2011-05-01

    In this paper, a new acoustic video camera system is developed and its calibration method is established. This system is built based on binocular vision and acoustical holography technology. With binocular vision method, the spatial distance between the microphone array and the moving vehicles is obtained, and the sound reconstruction plane can be established closely to the moving vehicle surface automatically. Then the sound video is regenerated closely to the moving vehicles accurately by acoustic holography method. With this system, the moving and stationary sound sources are treated differently and automatically, which makes the sound visualization of moving vehicles much quicker, more intuitively, and accurately. To verify this system, experiments for a stationary speaker and a non-stationary speaker are carried out. Further verification experiments for outdoor moving vehicle are also conducted. Successful video visualization results not only confirm the validity of the system but also suggest that this system can be a potential useful tool in vehicle's noise identification because it allows the users to find out the noise sources by the videos easily. We believe the newly developed system will be of great potential in moving vehicles' noise identification and control.

  16. Searching for Traces of Martian Life Using Holography

    NASA Astrophysics Data System (ADS)

    Ksanfomality, Leonid; Kompanets, Igor

    A sample of the Martian regolith to be delivered in future missions to Mars may provide an important information on traces of the extinct life when studied in the laboratory. Of course, there will be only few samples (by technical reasons) and their structure will inevitably be distorted by the extracting mechanisms. There is an another possibility, looking for a morphology sign affected by life, using a special TV camera, too. However it is very difficult to return an information of this kind of the TV, mainly due to the enormous amount of the information to be returned. The proposal made in this paper is to use a holography technics collecting many shots of undistorted objects on the surface of Mars using a special photosensitive film, and to return the film together with a soil sample. The mass of the film roll is neglectable when compared with a package of a soil sample. The holograph experiment results are a lot more informative then the stereo (two points of view), having the number points of view = object solid angle / solid angle resolution. The object may be examined from many sides. A resolution of such a film may be up to 5000 lines/mm, that is much, much higher than any TV image. The instrument proposed for the project is based on the most advanced new investigations in the holography, that permits to minimize (4 to 6 fold) the mass, sizes an power assumption of the camera. The goal of the project is to investigate micro morphology of the Martian surface features (stones, sand, dust). The Camera Specification (preliminary) Mass & Less than 4 kg Sizes (mm) & 300 times 100 times 150 Power assumption & averaged < 1W, pulse up to 100W. Lazer & YAG (Nd), 2nd harmonic Wavelength & 530 nm Structure & Fiber optics Photo film & High resolution (up to 5000 mm^{-1}) Object maximum size (mm)& 100 Frame size (mm) & 100 times 250 Number of shots & 12-20 In some sense all things, now widely used in space research, were risky innovations in the past. A holograph in

  17. Image quality improvement of parallel four-step phase-shifting digital holography by using the algorithm of parallel two-step phase-shifting digital holography.

    PubMed

    Kakue, Takashi; Moritani, Yuri; Ito, Kenichi; Shimozato, Yuki; Awatsuji, Yasuhiro; Nishio, Kenzo; Ura, Shogo; Kubota, Toshihiro; Matoba, Osamu

    2010-04-26

    We propose an algorithm that can improve the quality of the reconstructed image from the single hologram recorded by the optical system of the parallel four-step phase-shifting digital holography. The proposed algorithm applies the image-reconstruction algorithm of parallel two-step phase-shifting digital holography to the hologram so as to reduce errors in the reconstructed image and eliminate ghosts. We numerically and experimentally confirmed that the proposed algorithm decreased 25% in terms of root mean square error in amplitude, and eliminated the ghosts, respectively.

  18. THz holography in reflection using a high resolution microbolometer array.

    PubMed

    Zolliker, Peter; Hack, Erwin

    2015-05-04

    We demonstrate a digital holographic setup for Terahertz imaging of surfaces in reflection. The set-up is based on a high-power continuous wave (CW) THz laser and a high-resolution (640 × 480 pixel) bolometer detector array. Wave propagation to non-parallel planes is used to reconstruct the object surface that is rotated relative to the detector plane. In addition we implement synthetic aperture methods for resolution enhancement and compare Fourier transform phase retrieval to phase stepping methods. A lateral resolution of 200 μm and a relative phase sensitivity of about 0.4 rad corresponding to a depth resolution of 6 μm are estimated from reconstructed images of two specially prepared test targets, respectively. We highlight the use of digital THz holography for surface profilometry as well as its potential for video-rate imaging.

  19. Indefinite Plasmonic Beam Engineering by In-plane Holography

    PubMed Central

    Chen, J.; Li, L.; Li, T.; Zhu, S. N.

    2016-01-01

    Recent advances in controlling the optical phase at the sub-wavelength scale by meta-structures offer unprecedented possibilities in the beam engineering, holograms, and even invisible cloaks. In despite of developments of plasmonic beam engineering for definite beams, here, we proposed a new holographic strategy by in-plane diffraction process to access indefinite plasmonic beams, where a counterintuitive oscillating beam was achieved at a free metal surface that is against the common recognition of light traveling. Beyond the conventional hologram, our approach emphasizes on the phase correlation on the target, and casts an in-depth insight into the beam formation as a kind of long depth-of-field object. Moreover, in contrast to previous plasmonic holography with space light as references, our approach is totally fulfilled in a planar dimension that offers a thoroughly compact manipulation of the plasmonic near-field and suggests new possibilities in nanophotonic designs. PMID:27357133

  20. On-Line Metrology with Conoscopic Holography: Beyond Triangulation

    PubMed Central

    Álvarez, Ignacio; Enguita, Jose M.; Frade, María; Marina, Jorge; Ojea, Guillermo

    2009-01-01

    On-line non-contact surface inspection with high precision is still an open problem. Laser triangulation techniques are the most common solution for this kind of systems, but there exist fundamental limitations to their applicability when high precisions, long standoffs or large apertures are needed, and when there are difficult operating conditions. Other methods are, in general, not applicable in hostile environments or inadequate for on-line measurement. In this paper we review the latest research in Conoscopic Holography, an interferometric technique that has been applied successfully in this kind of applications, ranging from submicrometric roughness measurements, to long standoff sensors for surface defect detection in steel at high temperatures. PMID:22399984

  1. Three-dimensional information encryption and anticounterfeiting using digital holography.

    PubMed

    Shiu, Min-Tzung; Chew, Yang-Kun; Chan, Huang-Tian; Wong, Xin-Yu; Chang, Chi-Ching

    2015-01-01

    In this work, arbitrary micro phase-step digital holography with optical interferometry and digital image processing is utilized to obtain information about an image of a three-dimensional object and encrypting keys. Then, a computer-generated hologram is used for the purpose of holographic encryption. All information about the keys is required to perform the decryption, comprising the amplitude and phase distribution of the encrypting key, the distance of image reconstruction, zero-order term elimination, and twin-image term suppression. In addition to using identifiable information on different image planes and linear superposition processing hidden within the encrypted information, not only can we convey an important message, but we can also achieve anticounterfeiting. This approach retains the strictness of traditional holographic encryption and the convenience of digital holographic processing without image distortion. Therefore, this method provides better solutions to earlier methods for the security of the transmission of holographic information.

  2. Surface wave holography on designing subwavelength metallic structures.

    PubMed

    Chen, Yu-Hui; Fu, Jin-Xin; Li, Zhi-Yuan

    2011-11-21

    We report a method in the framework of surface wave holography to manipulate the electromagnetic wave on the metallic surface for realizing complicated electromagnetic wave transport functionalities in three-dimensional (3D) space. The method allows for direct determination of the metallic surface structure morphology for a given transport functionality, by means of writing desirable object information on the metallic surface via interference with a reference surface wave. We have employed the analytical approach to design and build metallic surface structures that realize arbitrary single-point focusing, arbitrary single-direction beam collimation, and simultaneous two-point focusing of electromagnetic wave in 3D space. Good agreement between numerical simulations and microwave experimental measurements has been found and confirms the power of the method in conceptually understanding and exploiting the surface electromagnetic wave on subwavelength metal structures.

  3. Cell imaging techniques based on digital image plane holography

    NASA Astrophysics Data System (ADS)

    Chen, Zhaoji; Gong, Wendi; Liu, Feifei; Wang, Huaying

    2010-11-01

    This paper has further studied the implementation methods and recording conditions of digital microscopic image plane holography (DMIPH). Two optical systems of DMIPH were built: one is recording hologram by using plane waves as reference light, the other is recording hologram by spherical reference light. Breast cancer cells and USAF resolution test target is used as tested samples in the experiment. Then the intensity distribution and three-dimensional shape information of the cells are got accurately. The experiment results show that DMIPH avoids the process of finding recording distance by using auto-focusing approach. The recording and reconstruction process of DMIPH is simple. Therefore DMIPH can be applied to the microscopic imaging of cells more effectively.

  4. Two-color holography concept (T-CHI)

    NASA Technical Reports Server (NTRS)

    Vikram, C. S.; Caulfield, H. J.; Workman, G. L.; Trolinger, J. D.; Wood, C. P.; Clark, R. L.; Kathman, A. D.; Ruggiero, R. M.

    1990-01-01

    The Material Processing in the Space Program of NASA-MSFC was active in developing numerous optical techniques for the characterization of fluids in the vicinity of various materials during crystallization and/or solidification. Two-color holographic interferometry demonstrates that temperature and concentration separation in transparent (T-CHI) model systems is possible. The experiments were performed for particular (succinonitrile) systems. Several solutions are possible in Microgravity Sciences and Applications (MSA) experiments on future Shuttle missions. The theory of the T-CHI concept is evaluated. Although particular cases are used for explanations, the concepts developed will be universal. A breadboard system design is also presented for ultimate fabrication and testing of theoretical findings. New developments in holography involving optical fibers and diode lasers are also incorporated.

  5. Terahertz digital holography image denoising using stationary wavelet transform

    NASA Astrophysics Data System (ADS)

    Cui, Shan-Shan; Li, Qi; Chen, Guanghao

    2015-04-01

    Terahertz (THz) holography is a frontier technology in terahertz imaging field. However, reconstructed images of holograms are inherently affected by speckle noise, on account of the coherent nature of light scattering. Stationary wavelet transform (SWT) is an effective tool in speckle noise removal. In this paper, two algorithms for despeckling SAR images are implemented to THz images based on SWT, which are threshold estimation and smoothing operation respectively. Denoised images are then quantitatively assessed by speckle index. Experimental results show that the stationary wavelet transform has superior denoising performance and image detail preservation to discrete wavelet transform. In terms of the threshold estimation, high levels of decomposing are needed for better denoising result. The smoothing operation combined with stationary wavelet transform manifests the optimal denoising effect at single decomposition level, with 5×5 average filtering.

  6. Real-time tomographic holography for augmented reality

    PubMed Central

    Galeotti, John M.; Siegel, Mel; Stetten, George

    2011-01-01

    The concept and instantiation of Real-Time Tomographic Holography (RTTH) for augmented reality is presented. RTTH enables natural hand-eye coordination to guide invasive medical procedures without requiring tracking or a head-mounted device. It places a real-time virtual image of an object's cross-section into its actual location, without noticeable viewpoint dependence (e.g. parallax error). The virtual image is viewed through a flat narrow-band Holographic Optical Element with optical power that generates an in-situ virtual image (within 1 m of the HOE) from a small SLM display without obscuring a direct view of the physical world. Rigidly fixed upon a medical ultrasound probe, an RTTH device could show the scan in its actual location inside the patient, even as the probe was moved relative to the patient. PMID:20634827

  7. Miniaturized digital holography sensor for distal three-dimensional endoscopy.

    PubMed

    Kolenovic, Ervin; Osten, Wolfgang; Klattenhoff, Reiner; Lai, Songcan; von Kopylow, Christoph; Jüptner, Werner

    2003-09-01

    A miniaturized sensor head for endoscopic measurements based on digital holography is described. The system was developed to measure the shape and the three-dimensional deformation of objects located at places to which there is no access by common measurement systems. A miniaturized optical sensor, including a complete digital holographic interferometer with a CCD camera, is placed at the end of a flexible endoscope. The diameter of the head is smaller than 10 mm. The system enables interferometric measurements to be made at speeds of as many as five reconstructions per second, and it can be used outside the laboratory under normal environmental conditions. Shape measurements are performed with two wavelengths for contouring, and the deformation is measured by digital holographic interferometry. To obtain full three-dimensional data in displacement measurements we illuminate the object sequentially from three different illumination directions. To increase the lateral resolution we use temporal phase shifting.

  8. Phase-shifting electron holography for atomic image reconstruction.

    PubMed

    Yamamoto, Kazuo; Sugawara, Yoshihiro; McCartney, Martha R; Smith, David J

    2010-08-01

    Phase-shifting electron holography was used to reconstruct the object-wave function of high-spatial-frequency specimens of HgCdTe, and the requirements for precise measurements were investigated. Fresnel fringes due to the electrostatic biprism caused serious calculation errors during the phase-shifting reconstruction. Uniform interference fringes, obtained by adjusting the biprism voltage to cancel out the Fresnel fringes, were needed to minimize these errors. High-resolution holograms of a HgCdTe single crystal were recorded with coarse interference fringes and a high visibility of 65% and then used to reconstruct the atomic-scale object wave. Although the spatial resolution (0.25 nm) of the transmission electron microscope was worse than the separation (0.16 nm) between Hg (or Cd) and Te columns, the crystal polarity was determined from the aberration-corrected object wave.

  9. Time-average TV holography for vibration fringe analysis

    SciTech Connect

    Kumar, Upputuri Paul; Kalyani, Yanam; Mohan, Nandigana Krishna; Kothiyal, Mahendra Prasad

    2009-06-01

    Time-average TV holography is widely used method for vibration measurement. The method generates speckle correlation time-averaged J0 fringes that can be used for full-field qualitative visualization of mode shapes at resonant frequencies of an object under harmonic excitation. In order to map the amplitudes of vibration, quantitative evaluation of the time-averaged fringe pattern is desired. A quantitative evaluation procedure based on the phase-shifting technique used in two beam interferometry has also been adopted for this application with some modification. The existing procedure requires a large number of frames to be recorded for implementation. We propose a procedure that will reduce the number of frames required for the analysis. The TV holographic system used and the experimental results obtained with it on an edge-clamped, sinusoidally excited square aluminium plate sample are discussed.

  10. Effects of quantization in phase-shifting digital holography.

    PubMed

    Mills, Godfrey A; Yamaguchi, Ichirou

    2005-03-01

    We discuss quantization effects of hologram recording on the quality of reconstructed images in phase-shifting digital holography. We vary bit depths of phase-shifted holograms in both numerical simulation and experiments and then derived the complex amplitude, which is subjected to Fresnel transformation for the image reconstruction. The influence of bit-depth limitation in quantization has been demonstrated in a numerical simulation for spot-array patterns with linearly varying intensities and a continuous intensity object. The objects are provided with uniform and random phase modulation. In experiments, digital holograms are originally recorded at 8 bits and the bit depths are changed to deliver holograms at bit depths of 1 to 8 bits for the image reconstruction. The quality of the reconstructed images has been evaluated for the different quantization levels.

  11. Femtosecond digital holography based on spatial light modulator

    NASA Astrophysics Data System (ADS)

    Lu, Xiaowei; Li, Jingzhen; Chen, Hongyi

    2013-12-01

    A high-speed digital holography based on a liquid crystal Spatial Light Modulator (LC-SLM) is presented. The production of multi-beam and control of their delay time can be achieved by controllable wavefront coding theory. In this paper, a Dammann phase grating was designed using a SLM to product multi-beam for extremely high speed digital holographic imaging. The required beam deflection could be obtained by adjusting programmable phase mask for controlling the spatial diffraction of input beam. The framing time is decided by interval beam angles and the distances between input plane and record plane. Theoretical derivate of generation multi beams based on SLM was proposed, and phase recover software was also made.

  12. Spectroscopic imaging, diffraction, and holography with x-ray photoemission

    SciTech Connect

    Not Available

    1992-02-01

    X-ray probes are capable of determining the spatial structure of an atom in a specific chemical state, over length scales from about a micron all the way down to atomic resolution. Examples of these probes include photoemission microscopy, energy-dependent photoemission diffraction, photoelectron holography, and X-ray absorption microspectroscopy. Although the method of image formation, chemical-state sensitivity, and length scales can be very different, these X-ray techniques share a common goal of combining a capability for structure determination with chemical-state specificity. This workshop will address recent advances in holographic, diffraction, and direct imaging techniques using X-ray photoemission on both theoretical and experimental fronts. A particular emphasis will be on novel structure determinations with atomic resolution using photoelectrons.

  13. Surface-Plasmon Holography with White-Light Illumination

    NASA Astrophysics Data System (ADS)

    Ozaki, Miyu; Kato, Jun-ichi; Kawata, Satoshi

    2011-04-01

    The recently emerging three-dimensional (3D) displays in the electronic shops imitate depth illusion by overlapping two parallax 2D images through either polarized glasses that viewers are required to wear or lenticular lenses fixed directly on the display. Holography, on the other hand, provides real 3D imaging, although usually limiting colors to monochrome. The so-called rainbow holograms—mounted, for example, on credit cards—are also produced from parallax images that change color with viewing angle. We report on a holographic technique based on surface plasmons that can reconstruct true 3D color images, where the colors are reconstructed by satisfying resonance conditions of surface plasmon polaritons for individual wavelengths. Such real 3D color images can be viewed from any angle, just like the original object.

  14. Surface-plasmon holography with white-light illumination.

    PubMed

    Ozaki, Miyu; Kato, Jun-ichi; Kawata, Satoshi

    2011-04-08

    The recently emerging three-dimensional (3D) displays in the electronic shops imitate depth illusion by overlapping two parallax 2D images through either polarized glasses that viewers are required to wear or lenticular lenses fixed directly on the display. Holography, on the other hand, provides real 3D imaging, although usually limiting colors to monochrome. The so-called rainbow holograms--mounted, for example, on credit cards--are also produced from parallax images that change color with viewing angle. We report on a holographic technique based on surface plasmons that can reconstruct true 3D color images, where the colors are reconstructed by satisfying resonance conditions of surface plasmon polaritons for individual wavelengths. Such real 3D color images can be viewed from any angle, just like the original object.

  15. Image quality improvement of polygon computer generated holography.

    PubMed

    Pang, Xiao-Ning; Chen, Ding-Chen; Ding, Yi-Cong; Chen, Yi-Gui; Jiang, Shao-Ji; Dong, Jian-Wen

    2015-07-27

    Quality of holographic reconstruction image is seriously affected by undesirable messy fringes in polygon-based computer generated holography. Here, several methods have been proposed to improve the image quality, including a modified encoding method based on spatial-domain Fraunhofer diffraction and a specific LED light source. Fast Fourier transform is applied to the basic element of polygon and fringe-invisible reconstruction is achieved after introducing initial random phase. Furthermore, we find that the image with satisfactory fidelity and sharp edge can be reconstructed by either a LED with moderate coherence level or a modulator with small pixel pitch. Satisfactory image quality without obvious speckle noise is observed under the illumination of bandpass-filter-aided LED. The experimental results are consistent well with the correlation analysis on the acceptable viewing angle and the coherence length of the light source.

  16. Phase-shifting interferometric holography of living cells

    NASA Astrophysics Data System (ADS)

    Giel, Dominik M.; Fratz, Markus; Brandenburg, Albrecht

    2006-02-01

    We present a phase-shifting holographic set-up for the microscopic imaging of adherent cells. The superposition of an object wave field and a reference wave is recorded on a digital sensor with three reference wave phases. The reference phases are then recovered by statistical analysis of the recorded intensities. Subsequently, the object wave phase is calculated by the generalized phase shifting algorithm. After phase unwrapping and background subtraction, the phase shift introduced by the adherent cell culture is reconstructed. As the interferograms are recorded in the image plane of the microsope objective, the full lateral resolution is achieved in contrast to off-axis holography where the reconstruction requires numerical propagation for the separation of 0 th and 1 st order. Our approach uses three arbitrary unknown reference phases and poses thus minimum requirements on the mechanical and thermal stability of the set-up. We give preliminary results of images from a Vero cell line and pollen grains.

  17. Triboelectricity evaluation of single toner particle by electron holography

    NASA Astrophysics Data System (ADS)

    Okada, H.; Shindo, D.; Kim, J. J.; Murakami, Y.; Kawase, H.

    2007-09-01

    Understanding electrification is particularly important in materials science since the use of charged particles, e.g., the electrophotographic printer with toner particles, is one of the most successful applications of electrification. However, the charge generation mechanism still remains unclear due to the lack of an appropriate method for evaluating individual fine particles. In this study, we describe an approach for determining the charge of a single toner particle that uses electron holography in combination with a shielding technique. Two long-standing problems in holographic studies—namely, perturbation of the reference electron wave and unwanted charging by illumination—have been overcome by introducing two types of shields in a microscope. Using this method, the amount of charge on a single toner particle was determined, and the surface charge distribution was found to be inhomogeneous. Furthermore, an in situ observation of triboelectricity was conducted inside the microscope.

  18. Triboelectricity evaluation of single toner particle by electron holography

    SciTech Connect

    Okada, H.; Shindo, D.; Kim, J. J.; Murakami, Y.; Kawase, H.

    2007-09-01

    Understanding electrification is particularly important in materials science since the use of charged particles, e.g., the electrophotographic printer with toner particles, is one of the most successful applications of electrification. However, the charge generation mechanism still remains unclear due to the lack of an appropriate method for evaluating individual fine particles. In this study, we describe an approach for determining the charge of a single toner particle that uses electron holography in combination with a shielding technique. Two long-standing problems in holographic studies--namely, perturbation of the reference electron wave and unwanted charging by illumination--have been overcome by introducing two types of shields in a microscope. Using this method, the amount of charge on a single toner particle was determined, and the surface charge distribution was found to be inhomogeneous. Furthermore, an in situ observation of triboelectricity was conducted inside the microscope.

  19. Molecular photoelectron holography with circularly polarized laser pulses.

    PubMed

    Yang, Weifeng; Sheng, Zhihao; Feng, Xingpan; Wu, Miaoli; Chen, Zhangjin; Song, Xiaohong

    2014-02-10

    We investigate the photoelectron momentum distribution of molecular-ion H2+driven by ultrashort intense circularly polarized laser pulses. Both numerical solutions of the time-dependent Schrödinger equation (TDSE) and a quasiclassical model indicate that the photoelectron holography (PH) with circularly polarized pulses can occur in molecule. It is demonstrated that the interference between the direct electron wave and rescattered electron wave from one core to its neighboring core induces the PH. Moreover, the results of the TDSE predict that there is a tilt angle between the interference pattern of the PH and the direction perpendicular to the molecular axis. Furthermore, the tilt angle is sensitively dependent on the wavelength of the driven circularly polarized pulse, which is confirmed by the quasiclassical calculations. The PH induced by circularly polarized laser pulses provides a tool to resolve the electron dynamics and explore the spatial information of molecular structures.

  20. Compressive holography reconstruction using phase-shifting interferometry

    NASA Astrophysics Data System (ADS)

    Zhang, Cheng; Shen, Chuan; Cheng, Hong; Zhang, Fen; Liu, Kaifeng; Zhang, Quanbing; Wei, Sui

    2015-05-01

    In classical compressive holography (CH), which based on the Gabor holography setup, two nonlinear terms are inherent in the intensity recorded by a 2D detector arrays, the DC term and the squared field term. The DC term (the term at the origin) can be eliminated by filtering the Fourier transform of the interference irradiance measurements using appropriate high-pass filter near the zero frequency. The nonlinearity caused by the squared field term can be neglected and modeled as a error term in the measurement. However, the above assumptions are significantly limited, which yields the degradation of reconstruction quality. In this paper, an novel scheme using phase-shifting method is presented. To accurately recover the complex optical field caused by the propagation of the object, without the influence of the DC term and the squared field term, a very effective method for removing these two terms is introduced. The complex optical field of the 3D object and the complex optical field at the detector plane can be precisely represented by a linear mapping model. The complex optical field at the recorder plane is obtained by phase-shifting interferometry with multiple shots. Then, the corresponded complex optical field at the detector plane can be successfully extracted from multiple captured holograms using conventional four phase-shifting interferometry. From such complex optical field at the record plane, including the amplitude and phase information, the complex optical field of the 3D object can be reconstructed via an optimization procedure. Numerical results demonstrate the effectiveness of our proposed method.

  1. Functional holography analysis: Simplifying the complexity of dynamical networks

    NASA Astrophysics Data System (ADS)

    Baruchi, Itay; Grossman, Danny; Volman, Vladislav; Shein, Mark; Hunter, John; Towle, Vernon L.; Ben-Jacob, Eshel

    2006-03-01

    We present a novel functional holography (FH) analysis devised to study the dynamics of task-performing dynamical networks. The latter term refers to networks composed of dynamical systems or elements, like gene networks or neural networks. The new approach is based on the realization that task-performing networks follow some underlying principles that are reflected in their activity. Therefore, the analysis is designed to decipher the existence of simple causal motives that are expected to be embedded in the observed complex activity of the networks under study. First we evaluate the matrix of similarities (correlations) between the activities of the network's components. We then perform collective normalization of the similarities (or affinity transformation) to construct a matrix of functional correlations. Using dimension reduction algorithms on the affinity matrix, the matrix is projected onto a principal three-dimensional space of the leading eigenvectors computed by the algorithm. To retrieve back information that is lost in the dimension reduction, we connect the nodes by colored lines that represent the level of the similarities to construct a holographic network in the principal space. Next we calculate the activity propagation in the network (temporal ordering) using different methods like temporal center of mass and cross correlations. The causal information is superimposed on the holographic network by coloring the nodes locations according to the temporal ordering of their activities. First, we illustrate the analysis for simple, artificially constructed examples. Then we demonstrate that by applying the FH analysis to modeled and real neural networks as well as recorded brain activity, hidden causal manifolds with simple yet characteristic geometrical and topological features are deciphered in the complex activity. The term "functional holography" is used to indicate that the goal of the analysis is to extract the maximum amount of functional

  2. Underwater digital holography for studies of marine plankton.

    PubMed

    Sun, H; Benzie, P W; Burns, N; Hendry, D C; Player, M A; Watson, J

    2008-05-28

    Conventional and digital holographies are proving to be increasingly important for studies of marine zooplankton and other underwater biological applications. This paper reports on the use of a subsea digital holographic camera (eHoloCam) for the analysis and identification of marine organisms and other subsea particles. Unlike recording on a photographic film, a digital hologram (e-hologram) is recorded on an electronic sensor and reconstructed numerically in a computer by simulating the propagation of the optical field in space. By comparison with other imaging techniques, an e-hologram has several advantages such as three-dimensional spatial reconstruction, non-intrusive and non-destructive interrogation of the recording sampling volume and the ability to record holographic videos. The basis of much work in optics lies in Maxwell's electromagnetic theory and holography is no exception: we report here on two of the numerical reconstruction algorithms we have used to reconstruct holograms obtained using eHoloCam and how their starting point lies in Maxwell's equations. Derivation of the angular spectrum algorithm for plane waves is provided as an exact method for the in-line numerical reconstruction of digital holograms. The Fresnel numerical reconstruction algorithm is derived from the angular spectrum method. In-line holograms are numerically processed before and after reconstruction to remove periodic noise from captured images and to increase image contrast. The ability of the Fresnel integration reconstruction algorithm to extend the reconstructed volume beyond the recording sensor dimensions is also shown with a 50% extension of the reconstruction area. Finally, we present some images obtained from recent deployments of eHoloCam in the North Sea and Faeroes Channel.

  3. Fast characterization of aluminum plates with TV-holography measurements of the frequency spectrum of multimode, quasi- monochromatic Lamb waves.

    PubMed

    Deán-Ben, X Luís; Trillo, Cristina; Doval, Angel F; Fernández, José L

    2011-06-01

    We introduce a novel approach for measuring the frequency spectrum of Lamb waves and, subsequently, for obtaining the thickness and the bulk wave velocities of isotropic, homogeneous plates. It is based on Fourier transforming a set of spatial and temporal samples of the acoustic displacement but, in contrast to the traditional approach that employs dense temporal sampling and a reduced set of spatial sampling locations, our data set is a sequence of 2-D high-resolution maps of the instantaneous out-of-plane displacement obtained with TV holography. We have devised three variants to obtain a set of points of the wavenumber-frequency space, based, respectively, on the spatial (1-D or 2-D) and on the spatio-temporal (3-D) Fourier transforms. The whole process to obtain these points can be easily automated and substantial time savings can be achieved, compared with other full-field techniques that require human intervention or with pointwise scanned probes. Experimental demonstration of the three variants with quasimonochromatic multimode Lamb waves in aluminum plates is presented. The characteristic parameters of the plates are calculated by fitting the theoretical model to the experimental points of the frequency spectrum. The analysis of the uncertainties shows that the accuracy of the method is only slightly lower than the accuracy of a previously reported method based on measuring the wavelength of single-modes, for which the data acquisition procedure is much slower.

  4. Acoustic cryocooler

    DOEpatents

    Swift, Gregory W.; Martin, Richard A.; Radenbaugh, Ray

    1990-01-01

    An acoustic cryocooler with no moving parts is formed from a thermoacoustic driver (TAD) driving a pulse tube refrigerator (PTR) through a standing wave tube. Thermoacoustic elements in the TAD are spaced apart a distance effective to accommodate the increased thermal penetration length arising from the relatively low TAD operating frequency in the range of 15-60 Hz. At these low operating frequencies, a long tube is required to support the standing wave. The tube may be coiled to reduce the overall length of the cryocooler. One or two PTR's are located on the standing wave tube adjacent antinodes in the standing wave to be driven by the standing wave pressure oscillations. It is predicted that a heat input of 1000 W at 1000 K will maintian a cooling load of 5 W at 80 K.

  5. Acoustic transducer

    DOEpatents

    Drumheller, Douglas S.

    2000-01-01

    An active acoustic transducer tool for use down-hole applications. The tool includes a single cylindrical mandrel including a shoulder defining the boundary of a narrowed portion over which is placed a sandwich-style piezoelectric tranducer assembly. The piezoelectric transducer assembly is prestressed by being placed in a thermal interference fit between the shoulder of the mandrel and the base of an anvil which is likewise positioned over the narrower portion of the mandrel. In the preferred embodiment, assembly of the tool is accomplished using a hydraulic jack to stretch the mandrel prior to emplacement of the cylindrical sandwich-style piezoelectric transducer assembly and anvil. After those elements are positioned and secured, the stretched mandrel is allowed to return substantially to its original (pre-stretch) dimensions with the result that the piezoelectric transducer elements are compressed between the anvil and the shoulder of the mandrel.

  6. Acoustic telemetry.

    SciTech Connect

    Drumheller, Douglas Schaeffer; Kuszmaul, Scott S.

    2003-08-01

    Broadcasting messages through the earth is a daunting task. Indeed, broadcasting a normal telephone conversion through the earth by wireless means is impossible with todays technology. Most of us don't care, but some do. Industries that drill into the earth need wireless communication to broadcast navigation parameters. This allows them to steer their drill bits. They also need information about the natural formation that they are drilling. Measurements of parameters such as pressure, temperature, and gamma radiation levels can tell them if they have found a valuable resource such as a geothermal reservoir or a stratum bearing natural gas. Wireless communication methods are available to the drilling industry. Information is broadcast via either pressure waves in the drilling fluid or electromagnetic waves in the earth and well tubing. Data transmission can only travel one way at rates around a few baud. Given that normal Internet telephone modems operate near 20,000 baud, these data rates are truly very slow. Moreover, communication is often interrupted or permanently blocked by drilling conditions or natural formation properties. Here we describe a tool that communicates with stress waves traveling through the steel drill pipe and production tubing in the well. It's based on an old idea called Acoustic Telemetry. But what we present here is more than an idea. This tool exists, it's drilled several wells, and it works. Currently, it's the first and only acoustic telemetry tool that can withstand the drilling environment. It broadcasts one way over a limited range at much faster rates than existing methods, but we also know how build a system that can communicate both up and down wells of indefinite length.

  7. Cloning and identification of a novel NhaD-type Na+/H+ antiporter from metagenomic DNA of the halophilic bacteria in soil samples around Daban Salt Lake.

    PubMed

    Zhang, Hua; Wang, Zhenhui; Wang, Lei; Mu, Ren; Zou, Zhi; Yuan, Kun; Wang, Yuekun; Wu, Haiping; Jiang, Juquan; Yang, Lifu

    2014-01-01

    In this study, metagenomic DNA was screened for the Na(+)/H(+) antiporter gene from the halophilic bacteria in Daban Salt Lake by selection in Escherichia coli KNabc lacking three major Na(+)/H(+) antiporters. One gene designated as Hb_nhaD encoding a novel NhaD-type Na(+)/H(+) antiporter was finally cloned. The presence of Hb_NhaD conferred tolerance of E. coli KNabc to up to 0.5 M NaCl and 0.2 M LiCl, and an alkaline pH. Hb_NhaD has the highest identity (70.6%) with a putative NhaD-type Na(+)/H(+) antiporter from an uncharacterized Clostridiaceae species, and also has lower identity with known NhaD-type Na(+)/H(+) antiporters from Halomonas elongata (20.8%), Alkalimonas amylolytica (19.0%), Vibrio parahaemolyticus (18.9%) and Vibrio cholerae (18.7 %). pH-dependent Na(+)(Li(+))/H(+) antiport activity was detected from everted membrane vesicles prepared from E. coli KNabc carrying Hb_nhaD. Hb_NhaD exhibited very high Na(+)(Li(+))/H(+) antiport activity over a wide pH range from 6.5 to 9.0 with the highest activity at pH 7.0 which is significantly different from those of the above known NhaD-type Na(+)/H(+) antiporters. Also, the apparent K m values of Hb_NhaD for Na(+) and Li(+) at pH 7.0 were determined to be 1.31 and 2.16, respectively. Based on the above results, we proposed that Hb_NhaD should be categorized as a novel NhaD-type Na(+)/H(+) antiporter.

  8. Defining the Na(+)/H(+) exchanger NHE1 interactome in triple-negative breast cancer cells.

    PubMed

    Amith, Schammim Ray; Vincent, Krista Marie; Wilkinson, Jodi Marie; Postovit, Lynne Marie; Fliegel, Larry

    2017-01-01

    Mounting evidence supports a major role for the Na(+)/H(+) exchanger NHE1 in cancer progression and metastasis. NHE1 is hyperactive at the onset of oncogenic transformation, resulting in intracellular alkalinization and extracellular microenvironmental acidification. These conditions promote invasion and facilitate metastasis. However, the signal pathways governing the regulation of exchanger activity are still unclear. This is especially important in the aggressively metastatic, triple-negative basal breast cancer subtype. We used affinity chromatography followed by mass spectrometry to identify novel and putative interaction partners of NHE1 in MDA-MB-231 triple-negative breast cancer cells. NHE1 associated with several types of proteins including cytoskeletal proteins and chaperones. We validated protein interactions by co-immunoprecipitation for: 14-3-3, AKT, α-enolase, CHP1, HSP70 and HSP90. Additionally, we used The Cancer Genome Atlas (TCGA) to study NHE1 gene expression in primary patient breast tumours versus adjacent normal tissue. NHE1 expression was elevated in breast tumour samples and, when broken down by breast cancer subtype, NHE1 gene expression was significantly lower in tumours of the basal subtype compared to luminal and HER2+ subtypes. Reverse phase protein array (RPPA) analysis showed that NHE1 expression positively correlated with p90(RSK) expression in basal, but not luminal, primary tumours. Other proteins were negatively correlated with NHE1 expression in basal breast cancer tumours. Taken together, our data provides the first insight into the signalling molecules that form the NHE1 interactome in triple-negative breast cancer cells. These results will focus our search for novel targeted therapies.

  9. Protein kinase B/Akt phosphorylates and inhibits the cardiac Na+/H+ exchanger NHE1.

    PubMed

    Snabaitis, Andrew K; Cuello, Friederike; Avkiran, Metin

    2008-10-10

    Sarcolemmal Na(+)/H(+) exchanger (NHE) activity is mediated by NHE isoform 1 (NHE1), which is subject to regulation by protein kinases. Our objectives were to determine whether NHE1 is phosphorylated by protein kinase B (PKB), identify any pertinent phosphorylation site(s), and delineate the functional consequences of such phosphorylation. Active PKBalpha phosphorylated in vitro a glutathione S-transferase (GST)-NHE1 fusion protein comprising amino acids 516 to 815 of the NHE1 carboxyl-terminal regulatory domain. PKBalpha-mediated phosphorylation of GST-NHE1 fusion proteins containing overlapping segments of this region localized the targeted residues to the carboxyl-terminal 190 amino acids (625 to 815) of NHE1. Mass spectrometry and phosphorylation analysis of mutated (Ser-->Ala) GST-NHE1 fusion proteins revealed that PKBalpha-mediated phosphorylation of NHE1 occurred principally at Ser648. Far-Western assays demonstrated that PKBalpha-mediated Ser648 phosphorylation abrogated calcium-activated calmodulin (CaM) binding to the regulatory domain of NHE1. In adult rat ventricular myocytes, adenovirus-mediated expression of myristoylated PKBalpha (myr-PKBalpha) increased cellular PKB activity, as confirmed by increased glycogen synthase kinase 3beta phosphorylation. Heterologously expressed myr-PKBalpha was present in the sarcolemma, colocalized with NHE1 at the intercalated disc regions, increased NHE1 phosphorylation, and reduced NHE1 activity following intracellular acidosis. Conversely, pharmacological inhibition of endogenous PKB increased NHE1 activity following intracellular acidosis. Our data suggest that NHE1 is a novel PKB substrate and that its PKB-mediated phosphorylation at Ser648 inhibits sarcolemmal NHE activity during intracellular acidosis, most likely by interfering with CaM binding and reducing affinity for intracellular H(+).

  10. Interaction between Na+ and H+ ions on Na-H exchange in sheep cardiac Purkinje fibers.

    PubMed

    Wu, M L; Vaughan-Jones, R D

    1997-04-01

    The interaction between Na+ and H+ ions upon Na-H exchange (NHE) was examined in sheep cardiac Purkinje fibers. Acid equivalent fluxes through NHE were examined using recordings of intracellular pH and Na+ in isolated preparations measured with ion selective microelectrodes. The extent of acid-extrusion by NHE was estimated from pH(i) recovery-rate, multiplied by beta(i) (intracellular buffering power) in response to an internal acid load induced by 20 mm NH4Cl removal (nominally HCO3- free media). A mixed inhibitory effect was found of extracellular H+ on external Na+-activation of NHE (i.e. an increase, at low pH(o), in the apparent Michaelis constant for external Na+ ions [K(Nao)(0.5)] and a decrease in the maximum transport rate [V(Nao)(max)]). In addition, we confirmed that the stoichiometry of Na(o) binding is unaffected by the pH(o) (between 7.5 and 6.5), showing a Hill coefficient close to one. The interaction between Na+ and H+ ions at the internal face of the cardiac NHE was also studied. Our evidence suggests that an increase in the intracellular Na+ ion concentration ([Na+]i) inhibits acid efflux and that this inhibition can be approximated by the decrease in thermodynamic driving force caused by reducing the transmembrane Na+ gradient. It appears, however, that small variations in [Na+]i from the normal resting level (intracellular sodium activity, a(i)Na = 7 to 13 mm) have little or no effect on acid efflux, suggesting that variation of a(i)Na is not a physiologically important controller of NHE activity in heart.

  11. Molecular characterization and expression analysis of the mulberry Na(+)/H(+) exchanger gene family.

    PubMed

    Cao, Boning; Long, Dingpei; Zhang, Meng; Liu, Changying; Xiang, Zhonghuai; Zhao, Aichun

    2016-02-01

    Na(+)/H(+) exchangers (NHXs) have important roles in cellular pH, and Na(+) and K(+) homeostasis in plants. Mulberry is not only an important traditional economic woody plant known for its leaves, which are the exclusive food source of the silkworm Bombyx mori, but it can also adapt to many different adverse conditions, including saline environments. However, little is known about the NHXs in this important perennial tree. In this study, we identified and cloned seven putative NHX gene family members from Morus atropurpurea based on a genome-wide analysis of the Morus genome database. A phylogenetic analysis and genomic organization of mulberry NHXs suggested that the mulberry NHX family forms three distinct subgroups. Transcriptome data and real-time PCR of different mulberry varieties under normal culture conditions revealed that the mulberry NHX family has a different tissue-specific pattern in the two mulberry species. The MaNHX genes' expression analyses under different stresses (salt and drought) and signal molecules (abscisic acid, salicylic acid, hydrogen peroxide and methyl jasmonate) revealed that MaNHXs not only could be induced by salt, drought and abscisic acid as describe in the literature, but were also induced by other signal molecules, which indicated that MaNHX members exhibited diverse and complicated expression patterns in different mulberry tissues under various abiotic stresses, phytohormones and plant signaling molecules. Our results provide some insights into new and emerging cellular and physiological functions of this group of H(+)-coupled cation exchangers, beyond their function in salt tolerance, and also provide the basis for further characterizations of MaNHXs' physiological functions.

  12. Inhibition of Na+/H+ Exchanger Isoform 1 Is Neuroprotective in Neonatal Hypoxic Ischemic Brain Injury

    PubMed Central

    Kleman, Neil; Uluc, Kutluay; Kendigelen, Pinar; Hagemann, Tracy; Akture, Erinc; Messing, Albee; Ferrazzano, Peter; Sun, Dandan

    2011-01-01

    Abstract We investigated the role of Na+/H+ exchanger isoform 1 (NHE-1) in neonatal hypoxia/ischemia (HI). HI was induced by unilateral ligation of the left common carotid artery in postnatal day 9 (P9) mice, and subsequent exposure of animals to 8% O2 for 55 min. A pre/posttreatment group received a selective and potent NHE-1 inhibitor HOE 642 (0.5 mg/kg, intraperitoneally) 5 min before HI, then at 24 and 48 h after HI. A posttreatment group received HOE 642 (0.5 mg/kg) at 10 min, 24 h, and 48 h after HI. Saline injections were used as vehicle controls. The vehicle-control brains at 72 h after HI exhibited neuronal degeneration in the ipsilateral hippocampus, striatum, and thalamus, as identified with Fluoro-Jade C positive staining and loss of microtubule-associated protein 2 (MAP2) expression. NHE-1 protein was upregulated in glial fibrillary acidic protein–positive reactive astrocytes. In HOE 642–treated brains, the morphologic hippocampal structures were better preserved and displayed less neurodegeneration and a higher level of MAP2 expression. Motor-learning deficit was detected at 4 weeks of age after HI in the vehicle control group. Inhibition of NHE-1 in P9 mice not only reduced neurodegeneration during the acute stage of HI but also improved the striatum-dependent motor learning and spatial learning at 8 weeks of age after HI. These findings suggest that NHE-1–mediated disruption of ionic homeostasis contributes to striatal and CA1 pyramidal neuronal injury after neonatal HI. Antioxid. Redox Signal. 14, 1803–1813. PMID:20712402

  13. Na+/H+ exchange in hypertension and in diabetes mellitus--facts and hypotheses.

    PubMed

    Siffert, W; Düsing, R

    1996-01-01

    An enhancement of Na+/H+ exchange (NHE) in blood cells of selected patients with essential hypertension and with diabetic nephropathy has been described by various investigators. Recent studies have shown that enhanced NHE activity persists in immortalized lymphoblasts from these patients after prolonged cell culture and, thus, appears to be under genetic control. Available evidence strongly argues against a mutation in the encoding gene or an overexpression of the NHE. Immortalized cells from hypertensive patients with enhanced NHE activity display two-fold enhanced agonist-induced rises of the cytosolic free Ca2+ concentration and the underlying reason was identified as an increased activation of pertussis toxin (PTX)-sensitive G proteins. The molecular mechanism(s) of this phenomenon have not yet been elucidated. It appears likely that similar changes contribute to the enhanced NHE activity phenotype in diabetic nephropathy, although experimental evidence for this is still lacking. An enhanced activation of PTX-sensitive G proteins could explain many of the hitherto unexplained phenomena in essential hypertension, e.g. inheritance, increased vasoconstriction, hypertrophy of remodeling of arterial blood vessels and the heart, enhanced platelet aggregation etc. In diabetes the same defect could provide the basis for the susceptibility to nephropathy, e.g. by enhancing the deleterious effects of autocrine and paracrine growth factors. Thus, the experimental approach of immortalizing blood cells from patients with essential hypertension and diabetic nephropathy has opened new horizons in the identification of genetically fixed abnormalities in intracellular signal transduction which could contribute to both pathologies and which can now be studied without the confounding influences of the diabetic or hypertensive in vivo milieu.

  14. Emerging roles of Na+/H+ exchangers in epilepsy and developmental brain disorders

    PubMed Central

    Falgoust, Lindsay; Pan, Jullie W.; Sun, Dandan; Zhang, Zhongling

    2016-01-01

    Epilepsy is a common central nervous system (CNS) disease characterized by recurrent transient neurological events occurring due to abnormally excessive or synchronous neuronal activity in the brain. The CNS is affected by systemic acid–base disorders, and epileptic seizures are sensitive indicators of underlying imbalances in cellular pH regulation. Na+/H+ exchangers (NHEs) are a family of membrane transporter proteins actively involved in regulating intracellular and organellar pH by extruding H+ in exchange for Na+ influx. Altering NHE function significantly influences neuronal excitability and plays a role in epilepsy. This review gives an overview of pH regulatory mechanisms in the brain with a special focus on the NHE family and the relationship between epilepsy and dysfunction of NHE isoforms. We first discuss how cells translocate acids and bases across the membrane and establish pH homeostasis as a result of the concerted effort of enzymes and ion transporters. We focus on the specific roles of the NHE family by detailing how the loss of NHE1 in two NHE mutant mice results in enhanced neuronal excitability in these animals. Furthermore, we highlight new findings on the link between mutations of NHE6 and NHE9 and developmental brain disorders including epilepsy, autism, and attention deficit hyperactivity disorder (ADHD). These studies demonstrate the importance of NHE proteins in maintaining H+ homeostasis and their intricate roles in the regulation of neuronal function. A better understanding of the mechanisms underlying NHE1, 6, and 9 dysfunctions in epilepsy formation may advance the development of new epilepsy treatment strategies. PMID:26965387

  15. CHRONICLE: Second International School on Coherent Optics and Holography, Varna, September 28—October 3, 1981

    NASA Astrophysics Data System (ADS)

    Bukhenskiĭ, M. F.; Semenov, A. S.

    1982-06-01

    A brief review is given of lectures and papers presented at the Second International School on Coherent Optics and Holography, held in Varna in 1981. The proceedings were divided into the following sessions: fiber optics, integrated optics, holography and optical data processing.

  16. Acoustic source for generating an acoustic beam

    DOEpatents

    Vu, Cung Khac; Sinha, Dipen N.; Pantea, Cristian

    2016-05-31

    An acoustic source for generating an acoustic beam includes a housing; a plurality of spaced apart piezo-electric layers disposed within the housing; and a non-linear medium filling between the plurality of layers. Each of the plurality of piezoelectric layers is configured to generate an acoustic wave. The non-linear medium and the plurality of piezo-electric material layers have a matching impedance so as to enhance a transmission of the acoustic wave generated by each of plurality of layers through the remaining plurality of layers.

  17. Canonical Acoustics and Its Application to Surface Acoustic Wave on Acoustic Metamaterials

    NASA Astrophysics Data System (ADS)

    Shen, Jian Qi

    2016-08-01

    In a conventional formalism of acoustics, acoustic pressure p and velocity field u are used for characterizing acoustic waves propagating inside elastic/acoustic materials. We shall treat some fundamental problems relevant to acoustic wave propagation alternatively by using canonical acoustics (a more concise and compact formalism of acoustic dynamics), in which an acoustic scalar potential and an acoustic vector potential (Φ ,V), instead of the conventional acoustic field quantities such as acoustic pressure and velocity field (p,u) for characterizing acoustic waves, have been defined as the fundamental variables. The canonical formalism of the acoustic energy-momentum tensor is derived in terms of the acoustic potentials. Both the acoustic Hamiltonian density and the acoustic Lagrangian density have been defined, and based on this formulation, the acoustic wave quantization in a fluid is also developed. Such a formalism of acoustic potentials is employed to the problem of negative-mass-density assisted surface acoustic wave that is a highly localized surface bound state (an eigenstate of the acoustic wave equations). Since such a surface acoustic wave can be strongly confined to an interface between an acoustic metamaterial (e.g., fluid-solid composite structures with a negative dynamical mass density) and an ordinary material (with a positive mass density), it will give rise to an effect of acoustic field enhancement on the acoustic interface, and would have potential applications in acoustic device design for acoustic wave control.

  18. What Is an Acoustic Neuroma

    MedlinePlus

    ... ANAUSA.org Connect with us! What is an Acoustic Neuroma? Each heading slides to reveal information. Important ... Acoustic Neuroma Important Points To Know About an Acoustic Neuroma An acoustic neuroma, also called a vestibular ...

  19. Femtosecond Time-Delay X-Ray Holography

    SciTech Connect

    Chapman, H N

    2007-10-24

    X-ray free-electron lasers (XFELs) will produce photon pulses with a unique and desirable combination of properties. Their short X-ray wavelengths allow penetration into materials and the ability to probe structure at and below the nanometer scale. Their ultra-short duration gives information about this structure at the fundamental time-scales of atoms and molecules. The extreme intensity of the pulses will allow this information to be acquired in a single shot, so that these studies can be carried out on non-repeatable processes or on weakly-scattering objects that will be modified by the pulse. A fourth property of XFEL pulses is their high transverse coherence, which brings the promise of decades of innovation in visible optics to the X-ray regime, such as holography, interferometry, and laser-based imaging. Making an effective use of XFEL pulses, however, will benefit from innovations that are new to both X-ray science and coherent optics. One such innovation is the new method of time-delay X-ray holography [1], recently demonstrated at the FLASH FEL at DESY in Hamburg, to measure the evolution of objects irradiated by intense pulses. One of the pressing questions about the high-resolution XFEL imaging and characterization of non-periodic or weakly-scattering objects is the effect of the intense FEL pulse on the object, during the interaction with that pulse. The method of single-particle diffraction imaging [2] requires a stream of reproducible particles (e.g. a protein complex or virus) inserted into the beam, whereby a coherent X-ray diffraction pattern is recorded. The pulse will completely destroy the object, but if the pulse is short enough the diffraction pattern will represent the undamaged object. This ultrafast flash imaging was demonstrated at the FLASH FEL using test objects that included microfabricated patterns in silicon nitride foils [3]. Those experiments showed that no damage occurred during the 30 fs duration pulse. However, in those

  20. Role of the Na+/H+ exchanger 3 in angiotensin II-induced hypertension

    PubMed Central

    Li, Xiao C.; Shull, Gary E.; Miguel-Qin, Elisa

    2015-01-01

    The renal mechanisms responsible for angiotensin II (ANG II)-induced hypertension remain incompletely understood. The present study tested the hypothesis that the Na+/H+ exchanger 3 (NHE3) is required for ANG II-induced hypertension in mice. Five groups of wild-type (Nhe3+/+) and Nhe3−/− mice were treated with vehicle or high pressor doses of ANG II (1.5 mg/kg/day ip, via minipump for 2 wk, or 10 pmol/min iv for 30 min). Under basal conditions, Nhe3−/− mice had significantly lower systolic blood pressure (SBP) and mean intra-arterial pressure (MAP) (P < 0.01), 24 h urine (P < 0.05), urinary Na+ (P < 0.01) and urinary K+ excretion (P < 0.01). In response to ANG II, SBP and MAP markedly increased in Nhe3+/+ mice in a time-dependent manner, as expected (P < 0.01). However, these acute and chronic pressor responses to ANG II were significantly attenuated in Nhe3−/− mice (P < 0.01). Losartan blocked ANG II-induced hypertension in Nhe3+/+ mice but induced marked mortality in Nhe3−/− mice. The attenuated pressor responses to ANG II in Nhe3−/− mice were associated with marked compensatory humoral and renal responses to genetic loss of intestinal and renal NHE3. These include elevated basal plasma ANG II and aldosterone and kidney ANG II levels, salt wasting from the intestines, increased renal AQP1, Na+/HCO3−, and Na+/K+-ATPase expression, and increased PKCα, mitogen-activated protein kinases ERK1/2, and glycogen synthase kinase 3αβ signaling proteins in the proximal tubules (P < 0.01). We concluded that NHE3 in proximal tubules of the kidney, along with NHE3 in intestines, is required for maintaining basal blood pressure as well as the full development of ANG II-induced hypertension. PMID:26242933

  1. Increased renal renin content in mice lacking the Na+/H+ exchanger NHE2.

    PubMed

    Hanner, Fiona; Chambrey, Régine; Bourgeois, Soline; Meer, Elliott; Mucsi, István; Rosivall, László; Shull, Gary E; Lorenz, John N; Eladari, Dominique; Peti-Peterdi, János

    2008-04-01

    Macula densa (MD) cells express the Na(+)/H(+) exchanger (NHE) isoform NHE2 at the apical membrane, which may play an important role in tubular salt sensing through the regulation of cell volume and intracellular pH. These studies aimed to determine whether NHE2 participates in the MD control of renin synthesis. Renal renin content and activity and elements of the MD signaling pathway were analyzed using wild-type (NHE2(+/+)) and NHE2 knockout (NHE2(-/-)) mice. Immunofluorescence studies indicated that NHE2(-/-) mice lack NHE3 at the MD apical membrane, so the other apical NHE isoform has not compensated for the lack of NHE2. Importantly, the number of renin-expressing cells in the afferent arteriole in NHE2(-/-) mice was increased approximately 2.5-fold using renin immunohistochemistry. Western blotting confirmed approximately 20% higher renal cortical renin content in NHE2(-/-) mice compared with wild type. No-salt diet for 1 wk significantly increased renin content and activity in NHE2(+/+) mice, but the response was blunted in NHE2(-/-) mice. Renal tissue renin activity and plasma renin concentration were elevated three- and twofold, respectively, in NHE2(-/-) mice compared with wild type. NHE2(-/-) mice also exhibited a significantly increased renal cortical cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase (mPGES) expression, indicating MD-specific mechanisms responsible for the increased renin content. Significant and chronic activation of ERK1/2 was observed in MD cells of NHE2(-/-) kidneys. Removal of salt or addition of NHE inhibitors to cultured mouse MD-derived (MMDD1) cells caused a time-dependent activation of ERK1/2. In conclusion, the NHE2 isoform appears to be important in the MD feedback control of renin secretion, and the signaling pathway likely involves MD cell shrinkage and activation of ERK1/2, COX-2, and mPGES, all well-established elements of the MD-PGE(2)-renin release pathway.

  2. Measurement of rabbit eardrum vibration through stroboscopic digital holography

    NASA Astrophysics Data System (ADS)

    De Greef, Daniël; Dirckx, Joris J. J.

    2014-05-01

    In this work, we present a setup for high-power single shot stroboscopic digital holography and demonstrate it in an application on rabbit eardrum vibration measurement. The setup is able to make full-field time-resolved measurements of vibrating surfaces with a precision in the nanometer range in a broad frequency range. The height displacement of the measured object is visualized over the entire surface as a function of time. Vibration magnitude and phase maps can be extracted from these data, the latter proving to be very useful to reveal phase delays across the surface. Such deviations from modal motion indicate energy losses due to internal damping, in contrast to purely elastic mechanics. This is of great interest in middle ear mechanics and finite element modelling. In our setup, short laser pulses are fired at selected instants within the surface vibration period and are recorded by a CCD camera. The timing of the pulses and the exposure of the camera are synchronized to the vibration phase by a microprocessor. The high-power frequency-doubled Nd:YAG laser produces pulses containing up to 5 mJ of energy, which is amply sufficient to record single-shot holograms. As the laser pulse length is 8 ns and the smallest time step of the trigger electronics is 1 μs, vibration measurements of frequencies up to 250 kHz are achievable through this method, provided that the maximum vibration amplitude exceeds a few nanometers. In our application, middle ear mechanics, measuring frequencies extend from 5 Hz to 20 kHz. The experimental setup will be presented, as well as results of measurements on a stretched circular rubber membrane and a rabbit's eardrum. Two of the challenges when measuring biological tissues, such as the eardrum, are low reflectivity and fast dehydration. To increase reflectivity, a coating is applied and to counteract the undesirable effects of tissue dehydration, the measurement setup and software have been optimized for speed without compromising

  3. Measurement of rabbit eardrum vibration through stroboscopic digital holography

    SciTech Connect

    De Greef, Daniël; Dirckx, Joris J. J.

    2014-05-27

    In this work, we present a setup for high-power single shot stroboscopic digital holography and demonstrate it in an application on rabbit eardrum vibration measurement. The setup is able to make full-field time-resolved measurements of vibrating surfaces with a precision in the nanometer range in a broad frequency range. The height displacement of the measured object is visualized over the entire surface as a function of time. Vibration magnitude and phase maps can be extracted from these data, the latter proving to be very useful to reveal phase delays across the surface. Such deviations from modal motion indicate energy losses due to internal damping, in contrast to purely elastic mechanics. This is of great interest in middle ear mechanics and finite element modelling. In our setup, short laser pulses are fired at selected instants within the surface vibration period and are recorded by a CCD camera. The timing of the pulses and the exposure of the camera are synchronized to the vibration phase by a microprocessor. The high-power frequency-doubled Nd:YAG laser produces pulses containing up to 5 mJ of energy, which is amply sufficient to record single-shot holograms. As the laser pulse length is 8 ns and the smallest time step of the trigger electronics is 1 μs, vibration measurements of frequencies up to 250 kHz are achievable through this method, provided that the maximum vibration amplitude exceeds a few nanometers. In our application, middle ear mechanics, measuring frequencies extend from 5 Hz to 20 kHz. The experimental setup will be presented, as well as results of measurements on a stretched circular rubber membrane and a rabbit's eardrum. Two of the challenges when measuring biological tissues, such as the eardrum, are low reflectivity and fast dehydration. To increase reflectivity, a coating is applied and to counteract the undesirable effects of tissue dehydration, the measurement setup and software have been optimized for speed without compromising

  4. Theory and Application of Auger and Photoelectron Diffraction and Holography

    NASA Astrophysics Data System (ADS)

    Chen, Xiang

    This dissertation addresses the theories and applications of three important surface analysis techniques: Auger electron diffraction (AED), x-ray photoelectron diffraction (XPD), and Auger and photoelectron holography. A full multiple-scattering scheme for the calculations of XPD, AED, and Kikuchi electron diffraction pattern from a surface cluster is described. It is used to simulate 64 eV M_{2,3}VV and 913 eV L_3VV AED patterns from Cu(001) surfaces, in order to test assertions in the literature that they are explicable by a classical "blocking" and channeling model. We find that this contention is not valid, and that only a quantum mechanical multiple-scattering calculation is able to simulate these patterns well. The same multiple scattering simulation scheme is also used to investigate the anomalous phenomena of peak shifts off the forward-scattering directions in photo -electron diffraction patterns of Mg KLL (1180 eV) and O 1s (955 eV) from MgO(001) surfaces. These shifts are explained by calculations assuming a short electron mean free path. Similar simulations of XPD from a CoSi_2(111) surface for Co-3p and Si-2p normal emission agree well with experimental diffraction patterns. A filtering process aimed at eliminating the self -interference effect in photoelectron holography is developed. A better reconstructed image from Si-2p XPD from a Si(001) (2 times 1) surface is seen at atomic resolution. A reconstruction algorithm which corrects for the anisotropic emitter waves as well as the anisotropic atomic scattering factors is used for holographic reconstruction from a Co-3p XPD pattern from a CoSi_2 surface. This new algorithm considerably improves the reconstructed image. Finally, a new reconstruction algorithm called "atomic position recovery by iterative optimization of reconstructed intensities" (APRIORI), which takes account of the self-interference terms omitted by the other holographic algorithms, is developed. Tests on a Ni-C-O chain and Si(111

  5. Hydrogen sulfide from a NaHS source attenuates dextran sulfate sodium (DSS)-induced inflammation via inhibiting nuclear factor-κB.

    PubMed

    Chen, Xi; Liu, Xi-shuang

    2016-03-01

    This study investigated the alleviating effects of hydrogen sulfide (H2S), derived from sodium hydrosulfide (NaHS), on inflammation induced by dextran sulfate sodium (DSS) in both in vivo and in vitro models. We found that NaHS injection markedly decreased rectal bleeding, diarrhea, and histological injury in DSS-challenged mice. NaHS (20 μmol/L) reversed DSS-induced inhibition in cell viability in Caco-2 cells and alleviated pro-inflammation cytokine expression in vivo and in vitro, indicating an anti-inflammatory function for H2S. It was also found that H2S may regulate cytokine expression by inhibiting the nuclear factor-κB (NF-κB) signaling pathway. In conclusion, our results demonstrated that H2S alleviated DSS-induced inflammation in vivo and in vitro and that the signal mechanism might be associated with the NF-κB signaling pathway.

  6. Hydrogen sulfide from a NaHS source attenuates dextran sulfate sodium (DSS)-induced inflammation via inhibiting nuclear factor-κB

    PubMed Central

    Chen, Xi; Liu, Xi-shuang

    2016-01-01

    This study investigated the alleviating effects of hydrogen sulfide (H2S), derived from sodium hydrosulfide (NaHS), on inflammation induced by dextran sulfate sodium (DSS) in both in vivo and in vitro models. We found that NaHS injection markedly decreased rectal bleeding, diarrhea, and histological injury in DSS-challenged mice. NaHS (20 μmol/L) reversed DSS-induced inhibition in cell viability in Caco-2 cells and alleviated pro-inflammation cytokine expression in vivo and in vitro, indicating an anti-inflammatory function for H2S. It was also found that H2S may regulate cytokine expression by inhibiting the nuclear factor-κB (NF-κB) signaling pathway. In conclusion, our results demonstrated that H2S alleviated DSS-induced inflammation in vivo and in vitro and that the signal mechanism might be associated with the NF-κB signaling pathway. PMID:26984841

  7. NapA Na(+)/H(+) Antiporter as a Sodium Extrusion System Supplementary to the Vacuolar Na(+)-ATPase in Enterococcus hirae.

    PubMed

    Kawano, M; Igarashi, K; Solioz, M; Kakinuma, Y

    1998-01-01

    Enterococcus hirae has two sodium extrusion systems: the NapA Na(+)/H(+) antiporter and the vacuolar Na(+)-ATPase. We found that a NapA mutant, WD4, which is deficient in Na(+)/H(+) antiporter activity, grew well in the pH range of 6 to 10 up to 200 mM sodium. This was due to active, potential-independent sodium extrusion by the Na(+)-ATPase, which was induced under these conditions. The NapA Na(+)/H(+) antiporter is thus not a prerequisite for growth of E. hirae in the presence of sodium, but plays a supplementary role in sodium extrusion at acidic pH.

  8. Symptoms of Acoustic Neuroma

    MedlinePlus

    ... Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself ... Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself ...

  9. NPL closes acoustics department

    NASA Astrophysics Data System (ADS)

    Extance, Andy

    2016-11-01

    The UK's National Physical Laboratory (NPL) has withdrawn funding for its acoustics, polymer and thermoelectrics groups, triggering concern among airborne acoustics specialists that the move could undermine the country's noise-management policies.

  10. Identifying the Acoustic Neuroma

    MedlinePlus

    ... Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself ... Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself ...

  11. Recent progress on fully analytic mesh based computer-generated holography

    NASA Astrophysics Data System (ADS)

    Park, Jae-Hyeung

    2016-10-01

    Computer generated holography plays a main role in the contents generation for holographic displays and digital archiving of three-dimensional objects. The fully analytic mesh based computer generated holography finds exact complex optical field for each triangular mesh of the three-dimensional objects for given sampling interval in the hologram plane without any approximation, enhancing the quality of the reconstruction. The mesh based processing rather than conventional point based one makes it compatible with most computer graphics techniques and efficient especially for large objects. In this paper, we present a few recent progress on fully analytic mesh based computer generated holography techniques including the dark line artifact removal, continuous shading of each mesh surface, the implementation of the angular reflectance distribution of the object surface and application of the texture map.

  12. Image authentication via sparsity-based phase-shifting digital holography

    NASA Astrophysics Data System (ADS)

    Chen, Wen; Chen, Xudong

    2015-03-01

    Digital holography has been widely studied in recent years, and a number of applications have been demonstrated. In this paper, we demonstrate that sparsity-based phase-shifting digital holography can be applied for image authentication. In phase-shifting digital holography, the holograms are sequentially recorded. Only small parts of each hologram are available for numerical reconstruction. It is found that nonlinear correlation algorithm can be applied to simply authenticate the reconstructed object. The results illustrate that the recovered image can be correctly verified. In the developed system, the recorded holograms are highly compressed which can facilitate data storage or transmission, and one simple authentication strategy has been established instead of applying relatively complex algorithms (such as compressive sensing) to recover the object.

  13. Scheme to improve the reconstructed image in parallel quasi-phase-shifting digital holography.

    PubMed

    Awatsuji, Yasuhiro; Sasada, Masaki; Fujii, Atsushi; Kubota, Toshihiro

    2006-02-10

    We propose a scheme to improve the reconstructed image in parallel quasi-phase-shifting digital holography. Parallel quasi-phase-shifting digital holography is a technique capable of noiseless instantaneous measurement of three-dimensional objects, and it implements four kinds of phase shifting at a time with an array of 2 x 2 phase-shifting devices located in the reference wave. In the phase-shifting calculation in the reconstruction process of the technique, the scheme assigns the 2 x 2 cell configuration for each pixel in the vertical direction and for each 1-pixel interval in the horizontal direction of the hologram recorded by the image sensor. We conduct both a numerical simulation and a preliminary experiment. The results show that the proposed scheme can improve the quality of the reconstructed image calculated by the conventional scheme of parallel quasi-phase-shifting digital holography we previously proposed, and then the effectiveness of the proposed scheme is verified.

  14. Partition calculation for zero-order and conjugate image removal in digital in-line holography.

    PubMed

    Ma, Lihong; Wang, Hui; Li, Yong; Jin, Hongzhen

    2012-01-16

    Conventional digital in-line holography requires at least two phase-shifting holograms to reconstruct an original object without zero-order and conjugate image noise. We present a novel approach in which only one in-line hologram and two intensity values (namely the object wave intensity and the reference wave intensity) are required. First, by subtracting the two intensity values the zero-order diffraction can be completely eliminated. Then, an algorithm, called partition calculation, is proposed to numerically remove the conjugate image. A preliminary experimental result is given to confirm the proposed method. The method can simplify the procedure of phase-shifting digital holography and improve the practical feasibility for digital in-line holography.

  15. High-speed 3D imaging by parallel phase-shifting digital holography

    NASA Astrophysics Data System (ADS)

    Awatsuji, Yasuhiro; Xia, Peng; Matoba, Osamu

    2015-07-01

    As a high-speed three-dimensional (3D) imaging technique, parallel phase-shifting digital holography is presented. This technique records a single hologram of an object with an image sensor having a phase-shift array device and reconstructs the instantaneous 3D image of the object with a computer. In this technique, a single hologram in which the multiple holograms required for phase-shifting digital holography are multiplexed by using space-division multiplexing technique pixel by pixel. Also, we present a high-speed parallel phase-shifting digital holography system. The system consists of an interferometer, a continuous-wave laser, and a high-speed polarization imaging camera. Motion pictures of dynamic phenomena at the rate of up to 1,000,000 frames per second have been achieved by the high-speed system.

  16. Study of 3D remote sensing system based on optical scanning holography

    NASA Astrophysics Data System (ADS)

    Zhao, Shihu; Yan, Lei

    2009-06-01

    High-precision and real-time remote sensing imaging system is an important part of remote sensing development. Holography is a method of wave front record and recovery which was presented by Dennis Gabor. As a new kind of holography techniques, Optical scanning holography (OSH) and remote sensing imaging are intended to be combined together and applied in acquisition and interference measurement of remote sensing. The key principles and applicability of OSH are studied and the mathematic relation between Fresnel Zone Plate number, numerical aperture and object distance was deduced, which are proved to be feasible for OSH to apply in large scale remote sensing. At last, a new three-dimensional reflected OSH remote sensing imaging system is designed with the combination of scanning technique to record hologram patterns of large scale remote sensing scenes. This scheme is helpful for expanding OSH technique to remote sensing in future.

  17. Investigation of silion MEMS structures subjected to thermal loading by digital holography

    NASA Astrophysics Data System (ADS)

    Ferraro, Pietro; De Nicola, Sergio; Finizio, Andrea; Coppola, Giuseppe; Iodice, Mario; Grilli, Simonetta; Magro, Carlo; Pierattini, Giovanni

    2003-10-01

    In this paper we study silicon MEMS (Microelectromechanical systems) structures subjected to thermal loading. Digital holography has been investigated as inspection tool to evaluate the deformation induced by the thermal loading. Application of DH on structures with several different geometries and shapes, like cantilever beams, bridges and membranes is reported and result will be discussed. Dimensions of the inspected microstructures, varies in the range 1-50μm. The experimental results shown that a "bimorph-effect" induces a deformation in MEMS structures. The difficulties encountered in performing the deformation analysis by digital holography in real-time will be afforded and discussed. A method with automatic focus tracking in Digital Holography is proposed allowing inspection of MEMS, under thermal loading, in real-time.

  18. "Best match" model and effect of Na+/H+ exchange on anion attachment to peptides and stability of formed adducts in negative ion electrospray mass spectrometry.

    PubMed

    Liu, Xiaohua; Cole, Richard B

    2014-02-01

    The "Best Match" model has been extended to account for the role that Na(+)/H(+) exchange plays on anion attachment in negative ion electrospray. Without any Na(+)/H(+) exchange on (Glu) fibrinopeptide B, the higher basicity anions F(-) and CH3COO(-) can hardly form observable adducts; however, after multiple Na(+)/H(+) exchanges, adduct formation is enabled. Moreover, dissociation pathways of CF3COO(-) adducts with singly deprotonated peptides that have undergone 0 to 3 Na(+)/H(+) exchanges exhibit a shift in CID product ions from losing predominately CF3COOH (case of 0 Na(+)/H(+) exchanges) to losing predominately CF3COO(-) (case of 3 Na(+)/H(+) exchanges). These phenomena can be rationalized by considering that Na(+) cations exchange at, and serve to "block", the most acidic sites, thereby forcing implicated anions to attach to lower acidity protons. In addition to forming ion pairs with carboxylate groups, Na(+) also participates in formation of tri-atomic ions of the form ANaA(-) during adduct dissociation. The fact that low gas-phase basicity (GB) anions preferentially form ANaA(-) species, even though high GB anions form more stable tri-atomic species, indicates that the monatomic ions were not in close contact in the initial adduct. The propensity for formation of stable anionic adducts is dependent on the degree of matching between anion GBs and GBapp of deprotonated sites on the peptide. The GBapp is raised dramatically as the charge state of the peptide increases via a through-space effect. The presence of Na(+) on carboxylate sites substantially decreases the GBapp by neutralizing these sites, while slightly increasing the intrinsic GBs by an inductive effect.

  19. Activation of the Na+/H+ antiport is not required for epidermal growth factor-dependent gene expression, growth inhibition or proliferation in human breast cancer cells.

    PubMed Central

    Church, J G; Mills, G B; Buick, R N

    1989-01-01

    Mitogen interaction with specific receptors in many cell types leads to activation of the Na+/H+ antiport and a resultant cytoplasmic alkalinization. Since amiloride inhibits both Na+/H+ exchange and cell proliferation, it has been hypothesized that activation of the antiport is an obligatory requirement for mitogenesis. However, concentrations of amiloride which inhibit the antiport also inhibit other cellular processes, including protein synthesis and phosphorylation. We have used an epidermal growth factor (EGF) receptor gene-amplified human breast cancer cell line, the growth of which is inhibited by high levels of EGF in culture (MDA-468) and a variant, the growth of which is stimulated by EGF (MDA-468-S4), along with two potent amiloride analogues to examine whether activation of the Na+/H+ antiport and cytoplasmic alkalinization is necessary for both EGF-dependent effects to occur. At concentrations of the amiloride analogues which block Na+/H+ exchange in both cell types by 76-98%, the EGF-dependent alterations in [3H]thymidine incorporation or induction in c-myc or c-fos gene transcription were unaltered. These results were confirmed by a lack of effect of the amiloride analogues on both the growth-stimulatory and growth-inhibitory effects on EGF in an anchorage-independent growth assay. Similarly, in pH-altered media that prevented normal cytoplasmic alkalinization, the response of both MDA-468 and MDA-468-S4 to EGF activation was unaltered. In addition, activation of the Na+/H+ antiport alone was not sufficient to induce c-myc and c-fos transcription in either cell type. Taken together, these data suggest that neither the Na+/H+ antiport nor cytoplasmic alkalinization are necessary or sufficient for either EGF-dependent growth stimulation or growth inhibition in MDA-468 human breast cancer cells. Images Fig. 3. PMID:2537620

  20. Acoustic emission frequency discrimination

    NASA Technical Reports Server (NTRS)

    Sugg, Frank E. (Inventor); Graham, Lloyd J. (Inventor)

    1988-01-01

    In acoustic emission nondestructive testing, broadband frequency noise is distinguished from narrow banded acoustic emission signals, since the latter are valid events indicative of structural flaws in the material being examined. This is accomplished by separating out those signals which contain frequency components both within and beyond (either above or below) the range of valid acoustic emission events. Application to acoustic emission monitoring during nondestructive bond verification and proof loading of undensified tiles on the Space Shuttle Orbiter is considered.

  1. Deep Water Ocean Acoustics

    DTIC Science & Technology

    2015-07-17

    under-ice scattering , bathymetric diffraction and the application of the ocean acoustic Parabolic Equation to infrasound. 2. Tasks a. Task 1...QSR-14C0172-Ocean Acoustics -063015 Figure 10. Estimated reflection coefficient as a function of frequency by taking the difference of downgoing and...OASIS, INC. 1 Report No. QSR-14C0172-Ocean Acoustics -063015 Quarterly Progress Report Technical and Financial Deep Water Ocean Acoustics

  2. Deep Water Ocean Acoustics

    DTIC Science & Technology

    2015-10-19

    OASIS, INC. 1 Report No. QSR-14C0172-Ocean Acoustics-093015 Quarterly Progress Report Technical and Financial Deep Water Ocean Acoustics...number. 1. REPORT DATE OCT 2015 2. REPORT TYPE 3. DATES COVERED 01-07-2015 to 30-09-2015 4. TITLE AND SUBTITLE Deep Water Ocean Acoustics...understanding of the impact of the ocean and seafloor environmental variability on deep- water (long-range) ocean acoustic propagation and to develop

  3. Shallow Water Acoustics Studies

    DTIC Science & Technology

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Shallow Water Acoustics Studies James F. Lynch MS #12...N00014-14-1-0040 http://acoustics.whoi.edu/sw06/ LONG TERM GOALS The long term goals of our shallow water acoustics work are to: 1) understand the...nature of low frequency (10-1500 Hz) acoustic propagation, scattering and noise in shallow water when strong oceanic variability is present in the

  4. Fast reconstruction of a bounded ultrasonic beam using acoustically induced piezo-luminescence

    SciTech Connect

    Kersemans, Mathias Lammens, Nicolas; Degrieck, Joris; Van Paepegem, Wim; Smet, Philippe F.

    2015-12-07

    We report on the conversion of ultrasound into light by the process of piezo-luminescence in epoxy with embedded BaSi{sub 2}O{sub 2}N{sub 2}:Eu as active component. We exploit this acoustically induced piezo-luminescence to visualize several cross-sectional slices of the radiation field of an ultrasonic piston transducer (f = 3.3 MHz) in both the near-field and the far-field. Simply combining multiple slices then leads to a fast representation of the 3D spatial radiation field. We have confronted the luminescent results with both scanning hydrophone experiments and digital acoustic holography results, and obtained a good correlation between the different approaches.

  5. Fast reconstruction of a bounded ultrasonic beam using acoustically induced piezo-luminescence

    NASA Astrophysics Data System (ADS)

    Kersemans, Mathias; Smet, Philippe F.; Lammens, Nicolas; Degrieck, Joris; Van Paepegem, Wim

    2015-12-01

    We report on the conversion of ultrasound into light by the process of piezo-luminescence in epoxy with embedded BaSi2O2N2:Eu as active component. We exploit this acoustically induced piezo-luminescence to visualize several cross-sectional slices of the radiation field of an ultrasonic piston transducer (f = 3.3 MHz) in both the near-field and the far-field. Simply combining multiple slices then leads to a fast representation of the 3D spatial radiation field. We have confronted the luminescent results with both scanning hydrophone experiments and digital acoustic holography results, and obtained a good correlation between the different approaches.

  6. Desensitization by external Na of the cyclic AMP-dependent Na+/H+ antiporter in trout red blood cells.

    PubMed

    Garcia-Romeu, F; Motais, R; Borgese, F

    1988-04-01

    The erythrocytes of the trout, Salmo gairdneri, react to beta-adrenergic stimulation by activating a cyclic AMP-dependent and amiloride-sensitive Na+/H+ antiporter (see Borgese, F., F. Garcia-Romeu, and R. Motais, Journal of General Physiology, 1986, 87:551-566). The present study traces the kinetic behavior of the unidirectional Na fluxes after stimulation by isoproterenol. A very considerable increase (100-fold) of the unidirectional Na influx (JNa(in)) follows the addition of isoproterenol to the erythrocyte suspension. After 1.5 min, JNa(in) falls suddenly, and asymptotically diminishes toward the nonstimulated flux level. The unidirectional Na efflux (JNa(out)) proceeds according to similar kinetics. The decrease of JNa(in) and JNa(out)is not linked to either a change in the driving forces of the transported ions or a decrease of the cyclic AMP concentration but to a desensitization of the Na+/H+ antiporter. This desensitization is dependent on the external Na concentration and is not controlled by internal Na, cell swelling, or external Ca.

  7. Molecular size of the Na+-H+ antiport in renal brush border membranes, as estimated by radiation inactivation

    SciTech Connect

    Beliveau, R.; Demeule, M.; Potier, M.

    1988-04-15

    The radiation inactivation method was applied to brush border membrane vesicles from rat kidney, in order to estimate the molecular size of the Na+-H+ antiporter. Sodium influx (1mM) driven by an acid intravesicular pH was unaffected by the high osmolarity of the cryoprotective solution. Initial rate of influx was estimated by linear regression performed on the first 10 seconds of transport: 0.512 pmol/micrograms protein/s. There was no binding component involved. Incubation performed in the presence of 1 mM amiloride, an inhibitor of the Na+-H+ antiport gave an initial rate of only 0.071 pmol/microgram/s, an 82% inhibition. Membrane vesicles were irradiated at -78 degrees C in a Gammacel Model 220. Sodium influx was reduced, as the dose of radiation increased, but the influx remained linear for the period of time (10s) during which the initial rate was estimated, indicating no alteration of the proton driving force during this time period. Amiloride-insensitive flux remained totally unaffected by the radiation dose, indicating that the passive permeability of the membrane towards sodium was unaffected. The amiloride-sensitive pathway presented a monoexponential profile of inactivation, allowing the molecular size to be estimated at 321 kDa. Based on DCCD-binding studies suggesting the molecular size of the monomer to be around 65 kDa for rat kidney, our results suggest that the functional transporter in the membrane to be a multimer.

  8. Gene amplification at a locus encoding a putative Na+/H+ antiporter confers sodium and lithium tolerance in fission yeast.

    PubMed Central

    Jia, Z P; McCullough, N; Martel, R; Hemmingsen, S; Young, P G

    1992-01-01

    We have identified a new locus, sodium 2 (sod2) based on selection for increased LiCl tolerance in fission yeast, Schizosaccharomyces pombe. Tolerant strains have enhanced pH-dependent Na+ export capacity and sodium transport experiments suggest that the gene encodes an Na+/H+ antiport. The predicted sod2 gene product can be placed in the broad class of transporters which possess 12 hydrophobic transmembrane domains. The protein shows some sequence similarity to the human and bacterial Na+/H+ antiporters. Overexpression of sod2 increased Na+ export capacity and conferred sodium tolerance. Osmotolerance was not affected and sod2 cells were unaffected for growth in K+. In a sod2 disruption strain cells were incapable of exporting sodium. They were hypersensitive to Na+ or Li+ and could not grow under conditions that approximate pH7. The sod2 gene amplification could be selected stepwise and the degree of such amplification correlated with the level of Na+ or Li+ tolerance. Images PMID:1314171

  9. Desensitization by external Na of the cyclic AMP-dependent Na+/H+ antiporter in trout red blood cells

    PubMed Central

    1988-01-01

    The erythrocytes of the trout, Salmo gairdneri, react to beta- adrenergic stimulation by activating a cyclic AMP-dependent and amiloride-sensitive Na+/H+ antiporter (see Borgese, F., F. Garcia- Romeu, and R. Motais, Journal of General Physiology, 1986, 87:551-566). The present study traces the kinetic behavior of the unidirectional Na fluxes after stimulation by isoproterenol. A very considerable increase (100-fold) of the unidirectional Na influx (JNa(in)) follows the addition of isoproterenol to the erythrocyte suspension. After 1.5 min, JNa(in) falls suddenly, and asymptotically diminishes toward the nonstimulated flux level. The unidirectional Na efflux (JNa(out)) proceeds according to similar kinetics. The decrease of JNa(in) and JNa(out)is not linked to either a change in the driving forces of the transported ions or a decrease of the cyclic AMP concentration but to a desensitization of the Na+/H+ antiporter. This desensitization is dependent on the external Na concentration and is not controlled by internal Na, cell swelling, or external Ca. PMID:2839593

  10. Identification of conserved polar residues important for salt tolerance by the Na+/H+ exchanger of Schizosaccharomyces pombe.

    PubMed

    Fliegel, Larry

    2005-01-01

    The Na+/H+ exchanger is a ubiquitous protein that transports Na+ and H+ in opposite directions across cell membranes. In fission yeast, the Na+/H+ exchanger sod2 plays a major role in the removal of excess detrimental intracellular sodium. The effect of mutagenesis of conserved polar amino acids of sod2 was examined by expressing 10 different mutant forms of sod2 in sod2 deficient S. pombe and characterizing salt tolerance. Asp145, 266, 267, and Glu173 were critical for proper function of sod2. Asp241 had an intermediate effect on sod2 function while mutation of Asp178 did not impair sod2 function. Simultaneous mutation of the Asp266, 267 pair impaired sod2 function. Mutation of each individual residue demonstrated that both were critical for sod2 function. Conservative mutations (Asp to Glu) of Asp266 and 267 failed to restore sod2 function. The results suggest that acidic residues associated with transmembrane segments are important in function, possibly being important in binding and coordinating cations.

  11. The mammalian Na+/H+ antiporters NHE-1, NHE-2, and NHE-3 are electroneutral and voltage independent, but can couple to an H+ conductance

    PubMed Central

    1995-01-01

    Na+/H+ exchange in vertebrates is thought to be electroneutral and insensitive to the membrane voltage. This basic concept has been challenged by recent reports of antiport-associated currents in the turtle colon epithelium (Post and Dawson, 1992, 1994). To determine the electrogenicity of mammalian antiporters, we used the whole-cell patch clamp technique combined with microfluorimetric measurements of intracellular pH (pHi). In murine macrophages, which were found by RT- PCR to express the NHE-1 isoform of the antiporter, reverse (intracellular Na(+)-driven) Na+/H+ exchange caused a cytosolic acidification and activated an outward current, whereas forward (extracellular Na(+)-driven) exchange produced a cytosolic alkalinization and reduced a basal outward current. The currents mirrored the changes in pHi, were strictly dependent on the presence of a Na+ gradient and were reversibly blocked by amiloride. However, the currents were seemingly not carried by the Na+/H+ exchanger itself, but were instead due to a shift in the voltage dependence of a preexisting H+ conductance. This was supported by measurements of the reversal potential (Erev) of tail currents, which identified H+ (equivalents) as the charge carrier. During Na+/H+ exchange, Erev changed along with the measured changes in pHi (by 60-69 mV/pH). Moreover, the current and Na+/H+ exchange could be dissociated. Zn2+, which inhibits the H+ conductance, reversibly blocked the currents without altering Na+/H+ exchange. In Chinese hamster ovary (CHO) cells, which lack the H+ conductance, Na+/H+ exchange produced pHi changes that were not accompanied by transmembrane currents. Similar results were obtained in CHO cells transfected with either the NHE-1, NHE-2, or NHE-3 isoforms of the antiporter, indicating that exchange through these isoforms is electroneutral. In all the isoforms tested, the amplitude and time- course of the antiport-induced pHi changes were independent of the holding voltage. We conclude that

  12. Binary optoacoustic holography with a spatial light modulator

    NASA Astrophysics Data System (ADS)

    Meyer, A.; Gspan, S.; Bernet, S.; Ritsch-Marte, M.

    2004-11-01

    A purely optical method to generate and to steer an ultrasonic beam is presented. The generation of the ultrasonic beam in the kilohertz to megahertz regime is achieved by using the optoacoustic effect in a layer attached to the surface of a water tank, which absorbs time-modulated laser pulses. In order to tailor the emitted acoustic wave, diffractive optics concepts are applied to acoustics. To this end, the laser light intensity distribution at the absorbing surface is controlled by sending a computer-calculated pattern to a transmissive high-resolution liquid-crystal display in the beam path. This results in an acoustic analog to the "diffractive optical elements" in laser optics, with the emitted ultrasonic wave emerging in a predetermined way. The proof of principle is demonstrated for examples such as phase gratings and binary Fresnel lenses. The optoacoustic ultrasound generation with holographic diffractive steering is a flexible method with the potential of new applications in ultrasound diagnostics.

  13. Binary optoacoustic holography with a spatial light modulator

    SciTech Connect

    Meyer, A.; Gspan, S.; Bernet, S.; Ritsch-Marte, M.

    2004-11-15

    A purely optical method to generate and to steer an ultrasonic beam is presented. The generation of the ultrasonic beam in the kilohertz to megahertz regime is achieved by using the optoacoustic effect in a layer attached to the surface of a water tank, which absorbs time-modulated laser pulses. In order to tailor the emitted acoustic wave, diffractive optics concepts are applied to acoustics. To this end, the laser light intensity distribution at the absorbing surface is controlled by sending a computer-calculated pattern to a transmissive high-resolution liquid-crystal display in the beam path. This results in an acoustic analog to the 'diffractive optical elements' in laser optics, with the emitted ultrasonic wave emerging in a predetermined way. The proof of principle is demonstrated for examples such as phase gratings and binary Fresnel lenses. The optoacoustic ultrasound generation with holographic diffractive steering is a flexible method with the potential of new applications in ultrasound diagnostics.

  14. Coding Acoustic Metasurfaces.

    PubMed

    Xie, Boyang; Tang, Kun; Cheng, Hua; Liu, Zhengyou; Chen, Shuqi; Tian, Jianguo

    2017-02-01

    Coding acoustic metasurfaces can combine simple logical bits to acquire sophisticated functions in wave control. The acoustic logical bits can achieve a phase difference of exactly π and a perfect match of the amplitudes for the transmitted waves. By programming the coding sequences, acoustic metasurfaces with various functions, including creating peculiar antenna patterns and waves focusing, have been demonstrated.

  15. Tutorial on architectural acoustics

    NASA Astrophysics Data System (ADS)

    Shaw, Neil; Talaske, Rick; Bistafa, Sylvio

    2002-11-01

    This tutorial is intended to provide an overview of current knowledge and practice in architectural acoustics. Topics covered will include basic concepts and history, acoustics of small rooms (small rooms for speech such as classrooms and meeting rooms, music studios, small critical listening spaces such as home theatres) and the acoustics of large rooms (larger assembly halls, auditoria, and performance halls).

  16. Low Complexity Compression and Speed Enhancement for Optical Scanning Holography

    PubMed Central

    Tsang, P. W. M.; Poon, T.-C.; Liu, J.-P.; Kim, T.; Kim, Y. S.

    2016-01-01

    In this paper we report a low complexity compression method that is suitable for compact optical scanning holography (OSH) systems with different optical settings. Our proposed method can be divided into 2 major parts. First, an automatic decision maker is applied to select the rows of holographic pixels to be scanned. This process enhances the speed of acquiring a hologram, and also lowers the data rate. Second, each row of down-sampled pixels is converted into a one-bit representation with delta modulation (DM). Existing DM-based hologram compression techniques suffers from the disadvantage that a core parameter, commonly known as the step size, has to be determined in advance. However, the correct value of the step size for compressing each row of hologram is dependent on the dynamic range of the pixels, which could deviate significantly with the object scene, as well as OSH systems with different opical settings. We have overcome this problem by incorporating a dynamic step-size adjustment scheme. The proposed method is applied in the compression of holograms that are acquired with 2 different OSH systems, demonstrating a compression ratio of over two orders of magnitude, while preserving favorable fidelity on the reconstructed images. PMID:27708410

  17. Holography and quantum states in elliptic de Sitter space

    NASA Astrophysics Data System (ADS)

    Halpern, Illan F.; Neiman, Yasha

    2015-12-01

    We outline a program for interpreting the higher-spin dS/CFT model in terms of physics in the causal patch of a dS observer. The proposal is formulated in "elliptic" de Sitter space d{S}_4/{Z}_2 , obtained by identifying antipodal points in dS 4. We discuss recent evidence that the higher-spin model is especially well-suited for this, since the antipodal symmetry of bulk solutions has a simple encoding on the boundary. For context, we test some other (free and interacting) theories for the same property. Next, we analyze the notion of quantum field states in the non-time-orientable d{S}_4/{Z}_2 . We compare the physics seen by different observers, with the outcome depending on whether they share an arrow of time. Finally, we implement the marriage between higher-spin holography and observers in d{S}_4/{Z}_2 , in the limit of free bulk fields. We succeed in deriving an observer's operator algebra and Hamiltonian from the CFT, but not her S-matrix. We speculate on the extension of this to interacting higher-spin theory.

  18. Interference and holography with femtosecond laser pulses of different colours.

    PubMed

    Odoulov, Serguey; Shumelyuk, Alexandr; Badorreck, Holger; Nolte, Stefan; Voit, Kay-Michael; Imlau, Mirco

    2015-02-05

    Interferometry and holography are two domains that are based on observation and recording of interference fringes from two light beams. While the aim of the first technique is to reveal and map the phase difference of two wave fronts, the main task of the second technique is to reconstruct one of the two recording waves via diffraction of the other wave from the recorded fringe pattern (hologram). To create fringes, mutually coherent waves from the same laser are commonly used. It is shown here that fringes can be observed and holograms can be recorded with ultrashort, sub-picosecond pulses even of different colour, generated in our experiment with two parametric amplifiers seeded, both by the same mode-locked Ti-sapphire laser. The appearance of permanent and transient gratings is confirmed by recording of an image-bearing hologram, by observation of two-beam coupling gain in a pump-probe experiment and by frequency conversion in Raman-Nath self-diffraction from a moving grating.

  19. Light-Front Holography and AdS/QCD Correspondence

    SciTech Connect

    Brodsky, Stanley J.; de Teramond, Guy F.

    2008-04-23

    Light-Front Holography is a remarkable consequence of the correspondence between string theory in AdS space and conformal field theories in physical-space time. It allows string modes {Phi}(z) in the AdS fifth dimension to be precisely mapped to the light-front wavefunctions of hadrons in terms of a specific light-front impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron. This mapping was originally obtained by matching the exact expression for electromagnetic current matrix elements in AdS space with the corresponding exact expression for the current matrix element using light-front theory in physical space-time. More recently we have shown that one obtains the identical holographic mapping using matrix elements of the energy-momentum tensor, thus providing an important consistency test and verification of holographic mapping from AdS to physical observables defined on the light-front. The resulting light-front Schrodinger equations predicted from AdS/QCD give a good representation of the observed meson and baryon spectra and give excellent phenomenological predictions for amplitudes such as electromagnetic form factors and decay constants.

  20. Detection of biological tissue in gels using pulsed digital holography

    NASA Astrophysics Data System (ADS)

    del Socorro Hernández-Montes, Maria; Pérez-López, C.; Mendoza Santoyo, Fernando; Muñoz Guevara, Luis Manuel

    2004-03-01

    An out of plane optical sensitive configuration for pulsed digital holography was used to detect biological tissue inside solid organic materials like gels. A loud speaker and a shaker were employed to produce a mechanical wave that propagates through the gel in such a way that it generates vibrational resonant modes and transient events on the gel surface. Gel surface micro displacements were observed between the firing of two laser pulses, both for a steady resonant mode and for different times during the transient event. The biological tissue sample inserted approximately 2 cm inside the gel diffracts the original mechanical wave and changes the resonant mode pattern or the transient wave on the gel surface. This fact is used to quantitatively measure the gel surface micro displacement. Comparison of phase unwrapped patterns, with and without tissue inside the gel, allows the rapid identification of the existence of tissue inside the gel. The results for the resonant and transient conditions show that the method may be reliably used to study, compare and distinguish data from inside homogeneous and in-homogeneous solid organic materials.

  1. In vitro imaging of ophthalmic tissue by digital interference holography

    NASA Astrophysics Data System (ADS)

    Potcoava, Mariana C.; Kay, Christine N.; Kim, Myung K.; Richards, David W.

    2010-01-01

    We used digital interference holography (DIH) for in vitro imaging of human optic nerve head and retina. Samples of peripheral retina, macula, and optic nerve head from two formaldehyde-preserved human eyes were dissected and mounted onto slides. Holograms were captured by a monochrome CCD camera (Sony XC-ST50, with 780 × 640 pixels and pixel size of ∼9 µm). Light source was a solid-state pumped dye laser with tunable wavelength range of 560-605 nm. Using about 50 wavelengths in this band, holograms were obtained and numerically reconstructed using custom software based on NI LabView. Tomographic images were produced by superposition of holograms. Holograms of all tissue samples were obtained with a signal-to-noise ratio of approximately 50 dB. Optic nerve head characteristics (shape, diameter, cup depth, and cup width) were quantified with a few micron resolution (4.06-4.8 µm). Multiple layers were distinguishable in cross-sectional images of the macula. To our knowledge, this is the first report of DIH use to image human macular and optic nerve tissue. DIH has the potential to become a useful tool for researchers and clinicians in the diagnosis and treatment of many ocular diseases, including glaucoma and a variety of macular diseases.

  2. Off-axis illumination direct-to-digital holography

    DOEpatents

    Thomas, Clarence E.; Price, Jeffery R.; Voelkl, Edgar; Hanson, Gregory R.

    2004-06-08

    Systems and methods are described for off-axis illumination direct-to-digital holography. A method of recording an off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis, includes: reflecting a reference beam from a reference mirror at a non-normal angle; reflecting an object beam from an object at an angle with respect to an optical axis defined by a focusing lens; focusing the reference beam and the object beam at a focal plane of a digital recorder to form the off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; digitally recording the off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; Fourier analyzing the recorded off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes by transforming axes of the recorded off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes in Fourier space to sit on top of a heterodyne carrier frequency defined as an angle between the reference beam and the object beam; applying a digital filter to cut off signals around an original origin; and then performing an inverse Fourier transform.

  3. Light-Front Holography and Hadronization at the Amplitude Level

    SciTech Connect

    Brodsky, Stanley J.; de Teramond, Guy; Shrock, Robert

    2008-07-25

    The correspondence between theories in anti-de Sitter space and conformal field theories in physical space-time leads to an analytic, semiclassical model for strongly-coupled QCD which has scale invariance at short distances and color confinement at large distances. Light-front holography is a remarkable feature of AdS/CFT: it allows hadronic amplitudes in the AdS fifth dimension to be mapped to frame-independent light-front wavefunctions of hadrons in physical space-time, thus providing a relativistic description of hadrons at the amplitude level. Some novel features of QCD are discussed, including the consequences of confinement for quark and gluon condensates and the behavior of the QCD coupling in the infrared. We suggest that the spatial support of QCD condensates is restricted to the interior of hadrons, since they arise due to the interactions of confined quarks and gluons. Chiral symmetry is thus broken in a limited domain of size 1=m{sub {pi}} in analogy to the limited physical extent of superconductor phases. A new method for computing the hadronization of quark and gluon jets at the amplitude level, an event amplitude generator, is outlined.

  4. Light-Front Holography and Novel Effects in QCD

    SciTech Connect

    Brodsky, Stanley J.; de Teramond, Guy F.

    2008-12-18

    The correspondence between theories in anti-de Sitter space and conformal field theories in physical space-time leads to an analytic, semiclassical model for strongly-coupled QCD. Light-front holography allows hadronic amplitudes in the AdS fifth dimension to be mapped to frame-independent light-front wavefunctions of hadrons in physical space-time, thus providing a relativistic description of hadrons at the amplitude level. We identify the AdS coordinate z with an invariant light-front coordinate {zeta} which separates the dynamics of quark and gluon binding from the kinematics of constituent spin and internal orbital angular momentum. The result is a single-variable light-front Schroedinger equation for QCD which determines the eigenspectrum and the light-front wavefunctions of hadrons for general spin and orbital angular momentum. The mapping of electromagnetic and gravitational form factors in AdS space to their corresponding expressions in light-front theory confirms this correspondence. Some novel features of QCD are discussed, including the consequences of confinement for quark and gluon condensates and the behavior of the QCD coupling in the infrared. The distinction between static structure functions such as the probability distributions computed from the square of the light-front wavefunctions versus dynamical structure functions which include the effects of rescattering is emphasized. A new method for computing the hadronization of quark and gluon jets at the amplitude level, an event amplitude generator, is outlined.

  5. Refocusing criterion via sparsity measurements in digital holography.

    PubMed

    Memmolo, Pasquale; Paturzo, Melania; Javidi, Bahram; Netti, Paolo A; Ferraro, Pietro

    2014-08-15

    Several automatic approaches have been proposed in the past to compute the refocus distance in digital holography (DH). However most of them are based on a maximization or minimization of a suitable amplitude image contrast measure, regarded as a function of the reconstruction distance parameter. Here we show that, by using the sparsity measure coefficient regarded as a refocusing criterion in the holographic reconstruction, it is possible to recover the focus plane and, at the same time, establish the degree of sparsity of digital holograms, when samples of the diffraction Fresnel propagation integral are used as a sparse signal representation. We employ a sparsity measurement coefficient known as Gini's index thus showing for the first time, to the best of our knowledge, its application in DH, as an effective refocusing criterion. Demonstration is provided for different holographic configurations (i.e., lens and lensless apparatus) and for completely different objects (i.e., a thin pure phase microscopic object as an in vitro cell, and macroscopic puppets) preparation.

  6. High resolution digital holography based on the point source scanning

    NASA Astrophysics Data System (ADS)

    Wang, Minchao; Wang, Dayong; Rong, Lu; Wang, Yunxin; Wang, Fengpeng; Lin, Qiaowen

    2016-10-01

    Digital holographic microscopy has been widely used for the imaging of micro-objects and biological samples. Lensless in-line digital holographic microscopy is capable of wide field-of-view imaging. However the spatial resolution of the reconstructed images is limited by the pixel size of the detector. The relative position shift between the sample and the detector can effectively improve the resolution in the traditional sub-pixel shifting method, but it requires a high precision of translation stage. To overcome this problem, we propose a method based on the point source scanning to realize sub-pixel shifting. High precision sub-pixel shifting is achieved easily by using the geometric between point source and detector. Through moving the point source, multiple holograms with sub-pixel shifts are captured. These holograms are merged together to obtained a high resolution hologram by a synthesizing algorithm. Then, the high resolution reconstructed image of the object can be obtained by the angular spectrum algorithm. The feasibility of the proposed method is demonstrated by simulation and experiments. A USAF resolution test target was used as the object. Compared with the traditional digital holography, a higher resolution reconstructed image is obtained by our method. The proposed method has the advantages of simple recording setup and lower precision requirement of the translation stage. It can achieve the wide field-of-view and high resolution imaging.

  7. Light-Front Holography and Hadronization at the Amplitude Level

    SciTech Connect

    Brodsky, Stanley J.; Teramond, Guy F. de; Shrock, Robert

    2008-10-13

    The correspondence between theories in anti-de Sitter space and conformal field theories in physical space-time leads to an analytic, semiclassical model for strongly-coupled QCD which has scale invariance at short distances and color confinement at large distances. Light-front holography is a remarkable feature of AdS/CFT: it allows hadronic amplitudes in the AdS fifth dimension to be mapped to frame-independent light-front wavefunctions of hadrons in physical space-time, thus providing a relativistic description of hadrons at the amplitude level. Some novel features of QCD are discussed, including the consequences of confinement for quark and gluon condensates and the behavior of the QCD coupling in the infrared. We suggest that the spatial support of QCD condensates is restricted to the interior of hadrons, since they arise due to the interactions of confined quarks and gluons. Chiral symmetry is thus broken in a limited domain of size 1/m{sub {pi}}, in analogy to the limited physical extent of superconductor phases. A new method for computing the hadronization of quark and gluon jets at the amplitude level, an event amplitude generator, is outlined.

  8. ELECTRON HOLOGRAPHY OF ELECTROMAGNETIC FIELDS - RECENT THEORETICAL ADVANCES.

    SciTech Connect

    BELEGGIA,M.; POZZI, G.; TONOMURA, A.

    2007-01-01

    It has been shown in this work that the Fourier space approach can be fruitfully applied to the calculation of the fields and the associated electron optical phase shift of several magnetic and electrostatic structures, like superconducting vortices in conventional and high-T{sub c} superconductors, reverse biased p-n junctions, magnetic domains and nanoparticles. In all these cases, this novel approach has led to unexpected but extremely interesting results, very often expressed in analytical form, which allow the quantitative and reliable interpretation of the experimental data collected by means of electron holography or of more conventional Lorentz microscopy techniques. Moreover, it is worth recalling that whenever long-range electromagnetic fields are involved, a physical model of the object under investigation is necessary in order to take into account correctly the perturbation of the reference wave induced by the tail of the field protruding into the vacuum. For these reasons, we believe that the Fourier space approach for phase computations we have introduced and discussed in this chapter will represent an invaluable tool for the investigation of electromagnetic fields at the meso- and nano-scale.

  9. Slavich recording materials for holography: an individual view

    NASA Astrophysics Data System (ADS)

    Phillips, Nicholas J.

    1998-02-01

    With the withdrawal of Agfa-Gevaert from the manufacturing of silver-halide recording materials, there is now a need to consider some of the super fine grain materials such as those made by Slavich in Russia. This paper addresses some of the problems encountered in the initial studies of appropriate chemical processing. It is considered that the most important issue is maintenance of a unique and achromatic Bragg condition over the whole working area of the hologram since such materials will probably have their greatest direct use in the formation of contact copies into polymer in a scan coped regime. Some of the most apparent difficulties of the process methods are discussed in this paper. A second issue of major importance appears to be associated with the current inability of these materials to create uniform developed density when exposed by precision digitally controlled exposure systems. This latter problem poses serious questions over the use of Slavich materials for lithography and digital holography.

  10. Low Complexity Compression and Speed Enhancement for Optical Scanning Holography

    NASA Astrophysics Data System (ADS)

    Tsang, P. W. M.; Poon, T.-C.; Liu, J.-P.; Kim, T.; Kim, Y. S.

    2016-10-01

    In this paper we report a low complexity compression method that is suitable for compact optical scanning holography (OSH) systems with different optical settings. Our proposed method can be divided into 2 major parts. First, an automatic decision maker is applied to select the rows of holographic pixels to be scanned. This process enhances the speed of acquiring a hologram, and also lowers the data rate. Second, each row of down-sampled pixels is converted into a one-bit representation with delta modulation (DM). Existing DM-based hologram compression techniques suffers from the disadvantage that a core parameter, commonly known as the step size, has to be determined in advance. However, the correct value of the step size for compressing each row of hologram is dependent on the dynamic range of the pixels, which could deviate significantly with the object scene, as well as OSH systems with different opical settings. We have overcome this problem by incorporating a dynamic step-size adjustment scheme. The proposed method is applied in the compression of holograms that are acquired with 2 different OSH systems, demonstrating a compression ratio of over two orders of magnitude, while preserving favorable fidelity on the reconstructed images.

  11. Digital reflection holography based systems development for MEMS testing

    NASA Astrophysics Data System (ADS)

    Singh, Vijay Raj; Liansheng, Sui; Asundi, Anand

    2010-05-01

    MEMS are tiny mechanical devices that are built onto semiconductor chips and are measured in micrometers and nanometers. Testing of MEMS device is an important part in carrying out their functional assessment and reliability analysis. Development of systems based on digital holography (DH) for MEMS inspection and characterization is presented in this paper. Two DH reflection systems, table-top and handheld types, are developed depending on the MEMS measurement requirements and their capabilities are presented. The methodologies for the systems are developed for 3D profile inspection and static & dynamic measurements, which is further integrated with in-house developed software that provides the measurement results in near real time. The applications of the developed systems are demonstrated for different MEMS devices for 3D profile inspection, static deformation/deflection measurements and vibration analysis. The developed systems are well suitable for the testing of MEMS and Microsystems samples, with full-field, static & dynamic inspection as well as to monitor micro-fabrication process.

  12. Interstellar Message Plaques: Application of White-Light Holography

    NASA Astrophysics Data System (ADS)

    Matloff, G. L.

    2002-01-01

    During Spring / Summer 2001, a prototype white-light holographic interstellar-probe message plaque was created under Contract H-29712D of NASA Marshall Spaceflight Center (MSFC), and commercial white-light holograms were tested for space-radiation tolerance at the MSFC Space Environment Facility (SEF) in Huntsville, AL, USA. Artist C Bangs' message plaque was created at the Center for Holographic Arts in Long Island City, NY. The 57.5 X 47.5 cm rainbow hologram was delivered to MSFC after framing by Simon Liu Inc., Brooklyn, NY, USA. The prototype message plaque, which is in the collection of the MSFC Space Transportation Directorate, has six multiplexed 2-D and 3-D images representing humans, the hypothetical interstellar spacecraft, and our position in the galaxy. Consultation with John Caulfield of Fisk University, an expert in holography, revealed that micron-thick holograms not much larger than a sheet of paper could contain hundreds of thousands of images, which opens the me ssage-plaque field considerably so that work of many artists could be included. Tests of commercial holograms at up to 100 MRad of simulated solar-wind radiation were performed at MSFC / SEF. Image-quality deterioriation was monitored using the image-color- histogram of the (trademarked) Adobe Photoshop software package. No significant deterioration occurred, which is in agreement with the literature. Holographic solar sails may be a propulsive application of this technology.

  13. Fabrication of submicron metallic grids with interference and phase-mask holography

    SciTech Connect

    Park, Joong-Mok; Kim, Tae-Geun; Constant, Kristen; Ho, Kai-Ming

    2011-01-25

    Complex, submicron Cu metallic mesh nanostructures are made by electrochemical deposition using polymer templates made from photoresist. The polymer templates are fabricated with photoresist using two-beam interference holography and phase mask holography with three diffracted beams. Freestanding metallic mesh structures are made in two separate electrodepositions with perpendicular photoresist grating templates. Cu mesh square nanostructures having large (52.6%) open areas are also made by single electrodeposition with a photoresist template made with a phase mask. These structures have potential as electrodes in photonic devices.

  14. Attosecond time-resolved imaging of molecular structure by photoelectron holography.

    PubMed

    Bian, Xue-Bin; Bandrauk, André D

    2012-06-29

    Dynamic imaging of the molecular structure of H(2)(+) is investigated by attosecond photoelectron holography. The interference between direct (reference) and backward rescattered (signal) photoelectrons in attosecond photoelectron holography reveals the birth time of both channels and the spatial information of molecular structure. This is confirmed by simulations with a semiclassical model and numerical solutions of the corresponding time-dependent Schrödinger equation, suggesting an attosecond time-resolved way of imaging molecular structure obtained from laser induced rescattering of ionized electrons. It is shown that both short and long rescattered electron trajectories can be imaged from the momentum distribution.

  15. Suppression of image autocorrelation artefacts in spectral domain optical coherence tomography and multiwave digital holography

    SciTech Connect

    Gelikonov, V M; Gelikonov, G V; Terpelov, D A; Shabanov, D V; Shilyagin, P A

    2012-05-31

    An improved method for suppressing image artefacts in spectral domain optical coherence tomography (SD OCT) and multiwave digital holography, caused by the influence of coherent noise in the course of successive registration of an autocorrelation component and informative signal is reported. The method allows complete suppression of all types of coherent noises, provided that the sample of values used to record the autocorrelation component satisfies the conditions of Kotelnikov's theorem: in SD OCT - for the transverse structure of the studied medium, in multiwave digital holography - for the envelop function of the radiation source frequency tuning spectrum.

  16. Single-shot femtosecond-pulsed phase-shifting digital holography.

    PubMed

    Kakue, Takashi; Itoh, Seiya; Xia, Peng; Tahara, Tatsuki; Awatsuji, Yasuhiro; Nishio, Kenzo; Ura, Shogo; Kubota, Toshihiro; Matoba, Osamu

    2012-08-27

    Parallel phase-shifting digital holography is capable of three-dimensional measurement of a dynamically moving object with a single-shot recording. In this letter, we demonstrated a parallel phase-shifting digital holography using a single femtosecond light pulse whose central wavelength and temporal duration were 800 nm and 96 fs, respectively. As an object, we set spark discharge in atmospheric pressure air induced by applying a high voltage to between two electrodes. The instantaneous change in phase caused by the spark discharge was clearly reconstructed. The reconstructed phase image shows the change of refractive index of air was -3.7 × 10(-4).

  17. A method of hard X-ray phase-shifting digital holography.

    PubMed

    Park, So Yeong; Hong, Chung Ki; Lim, Jun

    2016-07-01

    A new method of phase-shifting digital holography is demonstrated in the hard X-ray region. An in-line-type phase-shifting holography setup was installed in a 6.80 keV hard X-ray synchrotron beamline. By placing a phase plate consisting of a hole and a band at the focusing point of a Fresnel lens, the relative phase of the reference and objective beams could be successfully shifted for use with a three-step phase-shift algorithm. The system was verified by measuring the shape of a gold test pattern and a silica sphere.

  18. High-speed phase imaging by parallel phase-shifting digital holography.

    PubMed

    Kakue, Takashi; Yonesaka, Ryosuke; Tahara, Tatsuki; Awatsuji, Yasuhiro; Nishio, Kenzo; Ura, Shogo; Kubota, Toshihiro; Matoba, Osamu

    2011-11-01

    Parallel phase-shifting digital holography can obtain three-dimensional information of a dynamically moving object with high accuracy by using space-division multiplexing of multiple holograms required for phase-shifting interferometry. We demonstrated high-speed parallel phase-shifting digital holography and obtained images of the phase variation of air caused by a compressed gas flow sprayed from a nozzle. In particular, we found the interesting phenomenon of periodic phase distributions. Reconstructed images were obtained at frame rates of 20,000 and 180,000 frames per second.

  19. Microscopy imaging and quantitative phase contrast mapping in turbid microfluidic channels by digital holography.

    PubMed

    Paturzo, Melania; Finizio, Andrea; Memmolo, Pasquale; Puglisi, Roberto; Balduzzi, Donatella; Galli, Andrea; Ferraro, Pietro

    2012-09-07

    We show that sharp imaging and quantitative phase-contrast microcopy is possible in microfluidics in flowing turbid media by digital holography. In fact, in flowing liquids with suspended colloidal particles, clear vision is hindered and cannot be recovered by any other microscopic imaging technique. On the contrary, using digital holography, clear imaging is possible thanks to the Doppler frequency shift experienced by the photons scattered by the flowing colloidal particles, which do not contribute to the interference process, i.e. the recorded hologram. The method is illustrated and imaging results are demonstrated for pure phase objects, i.e. biological cells in microfluidic channels.

  20. Applications of Digital Holography: From Microscopy to 3D-Television

    NASA Astrophysics Data System (ADS)

    Kreis, T.

    2012-03-01

    The paper gives an overview of the applications of digital holography based on the one hand on CCD-recording, computer storage, and numerical reconstruction of the wave fields, and on the other hand on numerical calculation of computer generated holograms (CGH) and the transfer of these CGHs to spatial light modulators (SLM) for optical reconstruction of the wave fields. The first mentioned type of digital holography finds applications in digital holographic microscopy, particle analysis, and interferometric form and deformation measurement, while the second type constitutes the basis for holographic 3D TV. The space-bandwidth-problem occuring in this context is addressed and first partial solutions are presented.

  1. Digital microscopy using phase-shifting digital holography with two reference waves.

    PubMed

    Guo, Pengyi; Devaney, Anthony J

    2004-04-15

    A lensless, coherent optical microscope is described that uses a version of phase-shifting digital holography (PSDH) in conjunction with a field backpropagation algorithm to form coherent images of transmission-type objects. The PSDH is implemented by use of only two reference waves, in contrast with the usual implementation that requires four quadrature phase-shifting reference waves. Therefore only two digital holograms need to be recorded, and the complexity of the microscopic system is reduced. Experimental results are presented that compare images generated from conventional Gabor digital holography, two-reference-wave PSDH, and conventional white-light microscopy.

  2. Split-illumination electron holography for improved evaluation of electrostatic potential associated with electrophotography

    SciTech Connect

    Tanigaki, Toshiaki Aizawa, Shinji; Soon Park, Hyun; Sato, Kuniaki; Akase, Zentaro; Matsuda, Tsuyoshi; Murakami, Yasukazu; Shindo, Daisuke; Kawase, Hiromitsu

    2014-03-31

    Precise evaluation of the electrostatic potential distributions of and around samples with multiple charges using electron holography has long been a problem due to unknown perturbation of the reference wave. Here, we report the first practical application of split-illumination electron holography (SIEH) to tackle this problem. This method enables the use of a non-perturbed reference wave distant from the sample. SIEH revealed the electrostatic potential distributions at interfaces of the charged particles used for development in electrophotography and should lead to dramatic improvements in electrophotography.

  3. Twin image removal in digital in-line holography based on iterative inter-projections

    NASA Astrophysics Data System (ADS)

    Chen, Bing Kuan; Chen, Tai-Yu; Hung, Shau Gang; Huang, Sheng-Lung; Lin, Jiunn-Yuan

    2016-06-01

    A simple and efficient phase retrieval method based on the iterative inter-projections of the recorded Fourier modulus between two effective holographic planes is developed to eliminate the twin image in digital in-line holography. The proposed algorithm converges stably in phase extraction procedures without requiring any prior knowledge or sophisticated support of the object and is applicable to lensless Gabor and Fourier holography as well as holographic microscopy with imaging lenses. Numerical and experimental results suggest that the spatial resolution enhancement on the reconstructed image can be achieved with this technique due to the capability of recovering the diffraction phases of low-intensity signals.

  4. Atomic resolution electrostatic potential mapping of graphene sheets by off-axis electron holography

    SciTech Connect

    Cooper, David; Pan, Cheng-Ta; Haigh, Sarah

    2014-06-21

    Off-axis electron holography has been performed at atomic resolution with the microscope operated at 80 kV to provide electrostatic potential maps from single, double, and triple layer graphene. These electron holograms have been reconstructed in order to obtain information about atomically resolved and mean inner potentials. We propose that off-axis electron holography can now be used to measure the electrical properties in a range of two-dimensional semiconductor materials and three dimensional devices comprising stacked layers of films to provide important information about their electrical properties.

  5. Indoor acoustic gain design

    NASA Astrophysics Data System (ADS)

    Concha-Abarca, Justo Andres

    2002-11-01

    The design of sound reinforcement systems includes many variables and usually some of these variables are discussed. There are criteria to optimize the performance of the sound reinforcement systems under indoor conditions. The equivalent acoustic distance, the necessary acoustic gain, and the potential acoustic gain are parameters which must be adjusted with respect to the loudspeaker array, electric power and directionality of loudspeakers, the room acoustics conditions, the distance and distribution of the audience, and the type of the original sources. The design and installation of front of the house and monitoring systems have individual criteria. This article is about this criteria and it proposes general considerations for the indoor acoustic gain design.

  6. Twin-image reduction method for in-line digital holography using periphery and random reference phase-shifting techniques

    NASA Astrophysics Data System (ADS)

    Oshima, Teppei; Matsudo, Yusuke; Kakue, Takashi; Arai, Daisuke; Shimobaba, Tomoyoshi; Ito, Tomoyoshi

    2015-09-01

    Digital holography has the twin image problem that unwanted lights (conjugate and direct lights) overlap in the object light in the reconstruction process. As a method for extracting only the object light, phase-shifting digital holography is widely used; however, this method is not applicable for the observation of moving objects, because this method requires the recording of plural holograms. In this study, we propose a twin-image reduction method by combining the "periphery" method with the "random phase-shifting" method. The proposed method succeeded in improving the reconstruction quality, compared to other one-shot recording methods ("parallel phase-shifting digital holography" and "random phase-shifting").

  7. Na+/H+ and Na+/NH4+ exchange activities of zebrafish NHE3b expressed in Xenopus oocytes

    PubMed Central

    Ito, Yusuke; Kato, Akira; Hirata, Taku; Hirose, Shigehisa

    2014-01-01

    Zebrafish Na+/H+ exchanger 3b (zNHE3b) is highly expressed in the apical membrane of ionocytes where Na+ is absorbed from ion-poor fresh water against a concentration gradient. Much in vivo data indicated that zNHE3b is involved in Na+ absorption but not leakage. However, zNHE3b-mediated Na+ absorption has not been thermodynamically explained, and zNHE3b activity has not been measured. To address this issue, we overexpressed zNHE3b in Xenopus oocytes and characterized its activity by electrophysiology. Exposure of zNHE3b oocytes to Na+-free media resulted in significant decrease in intracellular pH (pHi) and intracellular Na+ activity (aNai). aNai increased significantly when the cytoplasm was acidified by media containing CO2-HCO3− or butyrate. Activity of zNHE3b was inhibited by amiloride or 5-ethylisopropyl amiloride (EIPA). Although the activity was accompanied by a large hyperpolarization of ∼50 mV, voltage-clamp experiments showed that Na+/H+ exchange activity of zNHE3b is electroneutral. Exposure of zNHE3b oocytes to medium containing NH3/NH4+ resulted in significant decreases in pHi and aNai and significant increase in intracellular NH4+ activity, indicating that zNHE3b mediates the Na+/NH4+ exchange. In low-Na+ (0.5 mM) media, zNHE3b oocytes maintained aNai of 1.3 mM, and Na+-influx was observed when pHi was decreased by media containing CO2-HCO3− or butyrate. These results provide thermodynamic evidence that zNHE3b mediates Na+ absorption from ion-poor fresh water by its Na+/H+ and Na+/NH4+ exchange activities. PMID:24401990

  8. The H2S Donor NaHS Changes the Expression Pattern of H2S-Producing Enzymes after Myocardial Infarction.

    PubMed

    Li, Na; Wang, Ming-Jie; Jin, Sheng; Bai, Ya-Dan; Hou, Cui-Lan; Ma, Fen-Fen; Li, Xing-Hui; Zhu, Yi-Chun

    2016-01-01

    Aims. To examine the expression patterns of hydrogen sulphide- (H2S-) producing enzymes in ischaemic heart tissue and plasma levels of H2S after 2 weeks of NaHS treatment after myocardial infarction (MI) and to clarify the role of endogenous H2S in the MI process. Results. After MI surgery, 2 weeks of treatment with the H2S donor NaHS alleviated ischaemic injury. Meanwhile, in ischemia myocardium, three H2S-producing enzymes, cystathionine γ-lyase (CSE), cystathionine-β-synthase (CBS), and 3-mercaptopyruvate sulfurtransferase (3-MST) significantly increased. Plasma H2S levels were also elevated. In vitro, NaHS treatment protected cardiomyocytes from hypoxic injury and raised CBS levels in a concentration-dependent manner. Different from in vivo results, however, CSE or 3-MST expression did not change. NaHS treatment increased the activity of CSE/CBS but not of 3-MST. When CSE was either knocked down (in vitro) or knocked out (in vivo), H2S levels significantly decreased, which subsequently exacerbated the ischaemic injury. Meanwhile, the expressions of CBS and 3-MST increased due to compensation. Conclusions. Exogenous H2S treatment changed the expressions of three H2S-producing enzymes and H2S levels after MI, suggesting a new and indirect regulatory mechanism for H2S production and its contribution to cardiac protection. Endogenous H2S plays an important role in protecting ischaemic tissue after MI.

  9. Light-Front Holography and Non-Perturbative QCD

    SciTech Connect

    Brodsky, Stanley J.; de Teramond, Guy F.; /Costa Rica U.

    2009-12-09

    The combination of Anti-de Sitter space (AdS) methods with light-front holography leads to a semi-classical first approximation to the spectrum and wavefunctions of meson and baryon light-quark bound states. Starting from the bound-state Hamiltonian equation of motion in QCD, we derive relativistic light-front wave equations in terms of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron at equal light-front time. These equations of motion in physical space-time are equivalent to the equations of motion which describe the propagation of spin-J modes in anti-de Sitter (AdS) space. Its eigenvalues give the hadronic spectrum, and its eigenmodes represent the probability distribution of the hadronic constituents at a given scale. Applications to the light meson and baryon spectra are presented. The predicted meson spectrum has a string-theory Regge form M{sup 2} = 4{kappa}{sup 2}(n + L + S = 2); i.e., the square of the eigenmass is linear in both L and n, where n counts the number of nodes of the wavefunction in the radial variable {zeta}. The space-like pion form factor is also well reproduced. One thus obtains a remarkable connection between the description of hadronic modes in AdS space and the Hamiltonian formulation of QCD in physical space-time quantized on the light-front at fixed light-front time {tau}. The model can be systematically improved by using its complete orthonormal solutions to diagonalize the full QCD light-front Hamiltonian or by applying the Lippmann-Schwinger method in order to systematically include the QCD interaction terms.

  10. Noise correction in power spectrum and image reconstruction with speckle holography.

    NASA Astrophysics Data System (ADS)

    Qiu, Yao-Hui; Zhang, Rui-Long; Lou, Ke; Lu, Ru-Wei; Liu, Zhong

    At first, the principle of speckle holography is introduced briefly, then some influences upon power spectrum arised from the noise in real data is analysed and a method to correct the noise bias is discussed. At last, a high resolution image reconstruction experiment for two double stars is reported.

  11. Doppler phase-shifting digital holography and its application to surface shape measurement.

    PubMed

    Kikuchi, Yuichi; Barada, Daisuke; Kiire, Tomohiro; Yatagai, Toyohiko

    2010-05-15

    Digital holography utilizing the optical Doppler effect is proposed in which the time variation of interference fringes is recorded using a high-speed CMOS camera. The complex amplitude diffracted from the object wave is extracted by time-domain Fourier transforming the recorded interference fringes. The method was used to measure the surface shape of a concave mirror under a disturbed environment.

  12. Noise and aliases in off-axis and phase-shifting holography.

    PubMed

    Gross, M; Atlan, M; Absil, E

    2008-04-10

    We have compared the respective efficiencies of off-axis and phase-shifting holography in terms of noise and aliases removal. The comparison is made by analyzing holograms of a USAF target backlit with laser illumination, recorded with a charge-coupled device camera. We show that it is essential to remove the local oscillator beam noise, especially at low illumination levels.

  13. Mapping the Large Millimeter Telescope primary reflector using photogrammetry: a first comparison with 12 GHz holography

    NASA Astrophysics Data System (ADS)

    Gale, David M.; Leon-Huerta, Andrea; Cabrera Cuevas, Lizeth; Castro Santos, David; Hernández Ríos, Emilio; Lucero Álvarez, Maribel; Tecuapetla Sosa, Esteban; Tzile Torres, Carlos; Sánchez-Argüelles, David; Narayanan, Gopal; Schloerb, F. Peter; Wilson, Grant W.; Smith, David R.

    2016-07-01

    The Large Millimeter Telescope (LMT) makes extensive use of 12 GHz holography during maintenance periods to finetune the alignment of primary reflector segments to the best-fit design parabola. Tracker measurements have also been used for this task, however the technique is severely limited by environmental noise and large data collection times, on the order of many hours for a single map. In 2015 we started photogrammetry trials as a complimentary measurement technique. Photogrammetry can offer reduced mapping times compared with laser trackers, and like holography, allows maps to be made at arbitrary elevation angles. Depending on the placement of reflecting targets, the technique can also provide higher spatial resolution than currently achieved using our holography system. Accurate photogrammetry requires a robust strategy for the incorporation of multiple camera stations, a task complicated by the size of the antenna, obstructions of the surface by the sub-reflector and tetrapod legs, and the practicability of using the site tower crane as a moving camera platform. Image scaling is also a major consideration, since photogrammetry lacks any inherent distance reference. Therefore appropriate scale bars must be fabricated and located within the camera field of view. Additional considerations relate to the size and placement of reflective targets, and the optimization of camera settings. In this paper we present some initial comparisons of laser tracker, holography and photogrammetry measurements taken in 2015, showing clearly the status of alignment for distinct zones of the currently operating 32.5 m primary collecting area.

  14. Creating an extended focus image of a tilted object in Fourier digital holography.

    PubMed

    Paturzo, Melania; Ferraro, Pietro

    2009-10-26

    We present a new method to numerically reconstruct images on a tilted plane by digital holography in Fourier configuration. The proposed technique is based on a quadratic deformation of spatial coordinates of the digital hologram. By this approach we demonstrate that it is possible to recover the extended focus image (EFI) of a tilted object in a single reconstruction step from the deformed hologram.

  15. The effect of object motion in Fraunhofer holography with application to velocity measurements

    NASA Technical Reports Server (NTRS)

    Dotson, W. P., Jr.

    1970-01-01

    Experimental results extend the Fraunhofer holography theory to include moving objects. Conclusions indicate objects may move up to ten times their mean diameter during observation time. Their motion produces fringe patterns descriptive of that motion from which it is possible to reconstruct the hologram and measure the velocity.

  16. Optical sectioning using a digital Fresnel incoherent-holography-based confocal imaging system

    PubMed Central

    Kelner, Roy; Katz, Barak; Rosen, Joseph

    2015-01-01

    We propose a new type of confocal microscope using Fresnel incoherent correlation holography (FINCH). Presented here is a confocal configuration of FINCH using a phase pinhole and point illumination that is able to suppress out-of-focus information from the recorded hologram and hence combine the super-resolution capabilities of FINCH with the sectioning capabilities of confocal microscopy. PMID:26413560

  17. AST Launch Vehicle Acoustics

    NASA Technical Reports Server (NTRS)

    Houston, Janice; Counter, D.; Giacomoni, D.

    2015-01-01

    The liftoff phase induces acoustic loading over a broad frequency range for a launch vehicle. These external acoustic environments are then used in the prediction of internal vibration responses of the vehicle and components which result in the qualification levels. Thus, predicting these liftoff acoustic (LOA) environments is critical to the design requirements of any launch vehicle. If there is a significant amount of uncertainty in the predictions or if acoustic mitigation options must be implemented, a subscale acoustic test is a feasible pre-launch test option to verify the LOA environments. The NASA Space Launch System (SLS) program initiated the Scale Model Acoustic Test (SMAT) to verify the predicted SLS LOA environments and to determine the acoustic reduction with an above deck water sound suppression system. The SMAT was conducted at Marshall Space Flight Center and the test article included a 5% scale SLS vehicle model, tower and Mobile Launcher. Acoustic and pressure data were measured by approximately 250 instruments. The SMAT liftoff acoustic results are presented, findings are discussed and a comparison is shown to the Ares I Scale Model Acoustic Test (ASMAT) results.

  18. Acoustic Translation of an Acoustically Levitated Sample

    NASA Technical Reports Server (NTRS)

    Barmatz, M. B.; Allen, J. L.

    1986-01-01

    Acoustic-levitation apparatus uses only one acoustic mode to move sample from one region of chamber to another. Sample heated and cooled quickly by translation between hot and cold regions of levitation chamber. Levitated sample is raised into furnace region by raising plunger. Frequency of sound produced by transducers adjusted by feedback system to maintain (102) resonant mode, which levitates sample midway between transducers and plunger regardless of plunger position.

  19. [Effects of Na(+)-HCO3- symport on ischemia/reperfusion injury; Na+/H+ exchanger inhibitor and buffer composition].

    PubMed

    Shimada, Yasuyuki

    2003-12-01

    We studied the impact of perfusate buffer composition on the relative degree of protection afforded by Na+/H+ exchanger (NHE) inhibition during ischemia as opposed to during reperfusion. Isolated rat hearts were perfused with bicarbonate- or HEPES-buffered medium. There was infusion of HOE 694 immediately before ischemia, during initial reperfusion, or during both of these periods. With bicarbonate-buffered medium, HOE 694 improved the post-ischemic recovery of left ventricular developed pressure (LVDP) when given before ischemia and before ischemia plus during reperfusion. In the presence of HEPES-buffered medium, however, HOE 694 significantly improved recovery of LVDP in all protocols. HOE 694 also provided an almost complete recovery of LVDP (88 +/- 9% vs 30 +/- 7% in controls) when given before ischemia plus during reperfusion. In conclusion, our results suggest that the influence of NHE activity during reperfusion on the extent of functional recovery is modulated significantly by perfusate buffer composition.

  20. Extensive genetic diversity in the Plasmodium falciparum Na+/H+ exchanger 1 transporter protein implicated in quinine resistance.

    PubMed

    Vinayak, Sumiti; Alam, Mohammad Tauqeer; Upadhyay, Mala; Das, Manoj K; Dev, Vas; Singh, Neeru; Dash, Aditya P; Sharma, Yagya D

    2007-12-01

    The Plasmodium falciparum Na(+)/H(+) exchanger (Pfnhe-1) locus at chromosome 13 and another locus at chromosome 9 have recently been proposed to influence quinine resistance. Here, we sequenced the ms4760 locus of the Pfnhe-1 gene from 244 P. falciparum isolates collected from five different regions of India. A total of 16 different ms4760 alleles (with one to five DNNND repeats) were observed among these isolates. Interestingly, areas with a high prevalence of chloroquine and sulfadoxine-pyrimethamine resistance showed more Pfnhe-1 DNNND repeats compared to low drug resistance areas. The extent of genetic diversity at the ms4760 locus also varied from one region to another, with expected heterozygosity values ranging from 0.47 to 0.88.