Design of photoacoustic microscope system based on labVIEW platform

A photoacoustic microscope system based on virtual instrument development environment is presented, including ultrasonic sensor, digital oscilloscope, laser diode, personal calculation and other hardware platforms. and developed supporting software and image reconstruction algorithms. In the subcutaneous angiography experiment, the distribution characteristics of the ear blood vessels in mouse were completely reproduced perfectly, and the spatial resolution of the system can reach 14um. The system and method can potentially to develop into a non-invasive biological tissue structure and functional imaging technique.

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Radar Coincidence Imaging under Grid Mismatch

ISRN Signal Processing ◽

10.1155/2014/987803 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 15

Author(s):

Dongze Li ◽

Xiang Li ◽

Yongqiang Cheng ◽

Yuliang Qin ◽

Hongqiang Wang

Keyword(s):

High Resolution ◽

Relative Motion ◽

Imaging Technique ◽

Correlation Method ◽

Single Pulse ◽

Reconstruction Algorithms ◽

Mismatch Error ◽

High Resolution Images ◽

Coincidence Imaging ◽

Image Reconstruction Algorithms

Radar coincidence imaging is an instantaneous imaging technique which does not depend on the relative motion between targets and radars. High-resolution, fine-quality images can be obtained using a single pulse either for stationary targets or for complexly maneuvering ones. There are two image-reconstruction algorithms used for radar coincidence imaging, that is, the correlation method and the parameterized method. In comparison with the former, the parameterized method can achieve much higher resolution but is seriously sensitive to grid mismatch. In the presence of grid mismatch, neither of the two algorithms can obtain recognizable high-resolution images. The above problem largely limits the applicability of radar coincidence imaging in actual imaging scenes where grid mismatch generally exists. This paper proposes a joint correlation-parameterization algorithm, which uses the correlation method to estimate the grid-mismatch error and then iteratively modifies the results of the parameterized method. The proposed algorithm can achieve high resolution with fine imagery quality under the grid mismatch. Examples are provided to illustrate the improvement of the proposed method.

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Design and Realization of Resolution Detection System for AD7730

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.241-244.190 ◽

2012 ◽

Vol 241-244 ◽

pp. 190-193

Author(s):

Xiao Ming Chang ◽

Bin Sun ◽

Shi Xuan Yao

Keyword(s):

Instrument Development ◽

High Precision ◽

Virtual Instrument ◽

Detection System ◽

Performance Parameter ◽

Analog Signal ◽

Sampling System ◽

Development Environment ◽

Signal Sampling ◽

Application System

Before using high-precision ADC AD7730 in analog signal sampling system, it’s required to measure the actual resolution if needed. This paper introduces the design of resolution detection system for ADC, which is used to evaluate the resolution performance parameter of ADC. First, a framework of the application system is designed, and specified at the example of 24bit ADC AD7730 application based on the Virtual Instrument Development Environment LabVIEW. Finally, actual resolutions of input channels are given and evaluated.

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Design of Supervision Software for Programmable Power Supply Based on Virtual Instrument Development Environment

2009 WRI World Congress on Computer Science and Information Engineering ◽

10.1109/csie.2009.65 ◽

2009 ◽

Cited By ~ 1

Author(s):

Jianmin Li ◽

Bin Zheng ◽

Wen Hou

Keyword(s):

Instrument Development ◽

Power Supply ◽

Virtual Instrument ◽

Development Environment

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Non-invasive in vivo optical monitoring of human placental oxygenation

10.21203/rs.3.rs-139102/v1 ◽

2021 ◽

Author(s):

Lin Wang ◽

Jeffrey Cochran ◽

Tiffany Ko ◽

Wesley Baker ◽

Kenneth Abramson ◽

...

Keyword(s):

Adverse Pregnancy Outcome ◽

Placental Tissue ◽

Blood Oxygenation ◽

Reconstruction Algorithms ◽

Non Invasive ◽

Tissue Phantom ◽

Placental Blood ◽

Adverse Pregnancy ◽

Image Reconstruction Algorithms

Abstract Direct assessment of human placental blood oxygenation can provide valuable information about placental function and, potentially, detect dysfunction. Currently however, no bedside tools exist for non-invasive monitoring of placental oxygenation. Here we report a continuous, non-invasive in vivo method to probe placental oxygen hemodynamics using deep penetrating Frequency Domain Diffuse Optical Spectroscopy (FD-DOS) with concurrent ultrasound (US) imaging. This multi-modal instrument facilitates assessment of placental oxygenation properties from image reconstruction algorithms that integrate anatomical US information about layer morphology with information from optics about functional hemodynamics. Tissue phantom experiments, simulations, and human subject studies validate the approach and demonstrate sensitivity to placental tissue located £ 5 cm below the surface. In a pilot study (n=24), human placental oxygen hemodynamics are measured non-invasively during maternal hyperoxia. Initial results suggest placental response to maternal hyperoxia may serve as a tool to detect placenta-related adverse pregnancy outcome and maternal vascular malperfusion of placenta, weeks before delivery.

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X-ray microtomography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100107058 ◽

1988 ◽

Vol 46 ◽

pp. 998-999

Author(s):

H.W. Deckman ◽

B.F. Flannery ◽

J.H. Dunsmuir ◽

K.D' Amico

Keyword(s):

Computed Tomography ◽

Internal Structure ◽

Imaging Technique ◽

Three Dimensional ◽

Tissue Structure ◽

Individual Element ◽

X Ray ◽

Non Invasive ◽

Panoramic Imaging ◽

Three Dimensional Images

We have developed a new X-ray microscope which produces complete three dimensional images of samples. The microscope operates by performing X-ray tomography with unprecedented resolution. Tomography is a non-invasive imaging technique that creates maps of the internal structure of samples from measurement of the attenuation of penetrating radiation. As conventionally practiced in medical Computed Tomography (CT), radiologists produce maps of bone and tissue structure in several planar sections that reveal features with 1mm resolution and 1% contrast. Microtomography extends the capability of CT in several ways. First, the resolution which approaches one micron, is one thousand times higher than that of the medical CT. Second, our approach acquires and analyses the data in a panoramic imaging format that directly produces three-dimensional maps in a series of contiguous stacked planes. Typical maps available today consist of three hundred planar sections each containing 512x512 pixels. Finally, and perhaps of most import scientifically, microtomography using a synchrotron X-ray source, allows us to generate maps of individual element.

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Three dimensional deblurring of transmitted-light brightfield micrographs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148654 ◽

1993 ◽

Vol 51 ◽

pp. 564-565

Author(s):

Santosh Bhattacharyya

Keyword(s):

Image Reconstruction ◽

Three Dimensional ◽

Transmitted Light ◽

Reconstruction Algorithms ◽

3D Image Reconstruction ◽

Structural Details ◽

Spread Function ◽

Early Testing ◽

Linearized Model ◽

Image Reconstruction Algorithms

Three dimensional microscopic structures play an important role in the understanding of various biological and physiological phenomena. Structural details of neurons, such as the density, caliber and volumes of dendrites, are important in understanding physiological and pathological functioning of nervous systems. Even so, many of the widely used stains in biology and neurophysiology are absorbing stains, such as horseradish peroxidase (HRP), and yet most of the iterative, constrained 3D optical image reconstruction research has concentrated on fluorescence microscopy. It is clear that iterative, constrained 3D image reconstruction methodologies are needed for transmitted light brightfield (TLB) imaging as well. One of the difficulties in doing so, in the past, has been in determining the point spread function of the system.We have been developing several variations of iterative, constrained image reconstruction algorithms for TLB imaging. Some of our early testing with one of them was reported previously. These algorithms are based on a linearized model of TLB imaging.

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Electrical Capacitance Volume Tomography (ECVT) for industrial and medical applications-An Overview

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v11i1.577 ◽

2015 ◽

Vol 11 (1) ◽

pp. 2897-2908

Author(s):

Mohammed S.Aljohani

Keyword(s):

Imaging Technique ◽

Three Dimensional ◽

Biological Processes ◽

Electrical Capacitance ◽

Image Reconstruction Techniques ◽

Phase Dynamics ◽

Non Invasive ◽

Electrical Capacitance Volume Tomography ◽

And Performance ◽

Optimization And Performance

Tomography is a non-invasive, non-intrusive imaging technique allowing the visualization of phase dynamics in industrial and biological processes. This article reviews progress in Electrical Capacitance Volume Tomography (ECVT). ECVT is a direct 3D visualizing technique, unlike three-dimensional imaging, which is based on stacking 2D images to obtain an interpolated 3D image. ECVT has recently matured for real time, non-invasive 3-D monitoring of processes involving materials with strong contrast in dielectric permittivity. In this article, ECVT sensor design, optimization and performance of various sensors seen in literature are summarized. Qualitative Analysis of ECVT image reconstruction techniques has also been presented.

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Radiation Dose Reduction in CT Torsion Measurement of the Lower Limb: Introduction of a New Ultra-Low Dose Protocol

Diagnostics ◽

10.3390/diagnostics11071209 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1209

Author(s):

Gabriel Keller ◽

Simon Götz ◽

Mareen Sarah Kraus ◽

Leonard Grünwald ◽

Fabian Springer ◽

...

Keyword(s):

Radiation Dose ◽

Radiation Exposure ◽

Lower Limb ◽

Low Dose ◽

Body Volume ◽

Reconstruction Algorithms ◽

Pelvic Radiograph ◽

Lower Radiation Dose ◽

Median Total Dose ◽

Image Reconstruction Algorithms

This study analyzed the radiation exposure of a new ultra-low dose (ULD) protocol compared to a high-quality (HQ) protocol for CT-torsion measurement of the lower limb. The analyzed patients (n = 60) were examined in the period March to October 2019. In total, 30 consecutive patients were examined with the HQ and 30 consecutive patients with the new ULD protocol comprising automatic tube voltage selection, automatic exposure control, and iterative image reconstruction algorithms. Radiation dose parameters as well as the contrast-to-noise ratio (CNR) and diagnostic confidence (DC; rated by two radiologists) were analyzed and potential predictor variables, such as body mass index and body volume, were assessed. The new ULD protocol resulted in significantly lower radiation dose parameters, with a reduction of the median total dose equivalent to 0.17 mSv in the ULD protocol compared to 4.37 mSv in the HQ protocol (p < 0.001). Both groups showed no significant differences in regard to other parameters (p = 0.344–0.923). CNR was 12.2% lower using the new ULD protocol (p = 0.033). DC was rated best by both readers in every HQ CT and in every ULD CT. The new ULD protocol for CT-torsion measurement of the lower limb resulted in a 96% decrease of radiation exposure down to the level of a single pelvic radiograph while maintaining good image quality.

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