Intravital Confocal and Two-photon Imaging of Dual-color Cells and Extracellular Matrix Mimics

Science.gov (United States)

Bal, Ufuk; Andresen, Volker; Baggett, Brenda; Utzinger, Urs

2013-01-01

To optimize imaging of cells in three dimensional culture we studied confocal backscattering, Second Harmonic Generation (SHG) and autofluorescence as source of contrast in extracellular matrix (ECM) mimics and evaluated the attenuation as well as bleaching of endogenous cellular fluorescence signals. All common ECM mimics exhibit contrast observable with confocal reflectance microscopy. SHG imaging on collagen I based hydrogels provides high contrast and good optical penetration depth. Agarose is a useful embedding medium because it allows for large optical penetration and exhibits minimal autofluorescence while still providing good reflectance to detect voids in the embedding medium. We labeled breast cancer cells’ outline with DsRed2 and nucleus with eGFP. DsRed2 can be excited with confocal imaging at 568nm, and with two photon excitation (TPE) in the red and longer NIR. eGFP was excited at 488nm for confocal and in the NIR for TPE. While there is small difference in the bleaching rate for eGFP between confocal and TPE we observed significant difference for DsRed2 where bleaching is strongest during TPE in the red wavelengths and smallest during confocal imaging. After a few hundred microns depth in a collagen I hydrogel, TPE fluorescence becomes twice as strong compared to confocal imaging. PMID:23380006

Virtual pinhole confocal microscope

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George, J.S.; Rector, D.M.; Ranken, D.M. [Los Alamos National Lab., NM (United States). Biophysics Group; Peterson, B. [SciLearn Inc. (United States); Kesteron, J. [VayTech Inc. (United States)

1999-06-01

Scanned confocal microscopes enhance imaging capabilities, providing improved contrast and image resolution in 3-D, but existing systems have significant technical shortcomings and are expensive. Researchers at Los Alamos National Laboratory have developed a novel approach--virtual pinhole confocal microscopy--that uses state of the art illumination, detection, and data processing technologies to produce an imager with a number of advantages: reduced cost, faster imaging, improved efficiency and sensitivity, improved reliability and much greater flexibility. Work at Los Alamos demonstrated proof of principle; prototype hardware and software have been used to demonstrate technical feasibility of several implementation strategies. The system uses high performance illumination, patterned in time and space. The authors have built functional confocal imagers using video display technologies (LCD or DLP) and novel scanner based on a micro-lens array. They have developed a prototype system for high performance data acquisition and processing, designed to support realtime confocal imaging. They have developed algorithms to reconstruct confocal images from a time series of spatially sub-sampled images; software development remains an area of active development. These advances allow the collection of high quality confocal images (in fluorescence, reflectance and transmission modes) with equipment that can inexpensively retrofit to existing microscopes. Planned future extensions to these technologies will significantly enhance capabilities for microscopic imaging in a variety of applications, including confocal endoscopy, and confocal spectral imaging.

Fluorescence confocal endomicroscopy in biological imaging

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Delaney, Peter; Thomas, Steven; Allen, John; McLaren, Wendy; Murr, Elise; Harris, Martin

2007-02-01

In vivo fluorescence microscopic imaging of biological systems in human disease states and animal models is possible with high optical resolution and mega pixel point-scanning performance using optimised off-the-shelf turn-key devices. There are however various trade-offs between tissue access and instrument performance when miniaturising in vivo microscopy systems. A miniature confocal scanning technology that was developed for clinical human endoscopy has been configured into a portable device for direct hand-held interrogation of living tissue in whole animal models (Optiscan FIVE-1 system). Scanning probes of 6.3mm diameter with a distal tip diameter of 5.0mm were constructed either in a 150mm length for accessible tissue, or a 300mm probe for laparoscopic interrogation of internal tissues in larger animal models. Both devices collect fluorescence confocal images (excitation 488 nm; emission >505 or >550 nm) comprised of 1024 x 1204 sampling points/image frame, with lateral resolution 0.7um; axial resolution 7um; FOV 475 x 475um. The operator can dynamically control imaging depth from the tissue surface to approx 250um in 4um steps via an internally integrated zaxis actuator. Further miniaturisation is achieved using an imaging contact probe based on scanning the proximal end of a high-density optical fibre bundle (~30,000 fibres) of small animal organs, albeit at lower resolution (30,000 sampling points/image). In rodent models, imaging was performed using various fluorescent staining protocols including fluorescently labelled receptor ligands, labelled antibodies, FITC-dextrans, vital dyes and labelled cells administered topically or intravenously. Abdominal organs of large animals were accessed laparoscopically and contrasted using i.v. fluorescein-sodium. Articular cartilage of sheep and pigs was fluorescently stained with calcein-AM or fluorescein. Surface and sub-surface cellular and sub-cellular details could be readily visualised in vivo at high

Three-dimensional imaging of porous media using confocal laser scanning microscopy.

Science.gov (United States)

Shah, S M; Crawshaw, J P; Boek, E S

2017-02-01

In the last decade, imaging techniques capable of reconstructing three-dimensional (3-D) pore-scale model have played a pivotal role in the study of fluid flow through complex porous media. In this study, we present advances in the application of confocal laser scanning microscopy (CLSM) to image, reconstruct and characterize complex porous geological materials with hydrocarbon reservoir and CO 2 storage potential. CLSM has a unique capability of producing 3-D thin optical sections of a material, with a wide field of view and submicron resolution in the lateral and axial planes. However, CLSM is limited in the depth (z-dimension) that can be imaged in porous materials. In this study, we introduce a 'grind and slice' technique to overcome this limitation. We discuss the practical and technical aspects of the confocal imaging technique with application to complex rock samples including Mt. Gambier and Ketton carbonates. We then describe the complete workflow of image processing to filtering and segmenting the raw 3-D confocal volumetric data into pores and grains. Finally, we use the resulting 3-D pore-scale binarized confocal data obtained to quantitatively determine petrophysical pore-scale properties such as total porosity, macro- and microporosity and single-phase permeability using lattice Boltzmann (LB) simulations, validated by experiments. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.

Super-resolution for everybody: An image processing workflow to obtain high-resolution images with a standard confocal microscope.

Science.gov (United States)

Lam, France; Cladière, Damien; Guillaume, Cyndélia; Wassmann, Katja; Bolte, Susanne

2017-02-15

In the presented work we aimed at improving confocal imaging to obtain highest possible resolution in thick biological samples, such as the mouse oocyte. We therefore developed an image processing workflow that allows improving the lateral and axial resolution of a standard confocal microscope. Our workflow comprises refractive index matching, the optimization of microscope hardware parameters and image restoration by deconvolution. We compare two different deconvolution algorithms, evaluate the necessity of denoising and establish the optimal image restoration procedure. We validate our workflow by imaging sub resolution fluorescent beads and measuring the maximum lateral and axial resolution of the confocal system. Subsequently, we apply the parameters to the imaging and data restoration of fluorescently labelled meiotic spindles of mouse oocytes. We measure a resolution increase of approximately 2-fold in the lateral and 3-fold in the axial direction throughout a depth of 60μm. This demonstrates that with our optimized workflow we reach a resolution that is comparable to 3D-SIM-imaging, but with better depth penetration for confocal images of beads and the biological sample. Copyright © 2016 Elsevier Inc. All rights reserved.

Photonics-Based Microwave Image-Reject Mixer

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Dan Zhu

2018-03-01

Full Text Available Recent developments in photonics-based microwave image-reject mixers (IRMs are reviewed with an emphasis on the pre-filtering method, which applies an optical or electrical filter to remove the undesired image, and the phase cancellation method, which is realized by introducing an additional phase to the converted image and cancelling it through coherent combination without phase shift. Applications of photonics-based microwave IRM in electronic warfare, radar systems and satellite payloads are described. The inherent challenges of implementing photonics-based microwave IRM to meet specific requirements of the radio frequency (RF system are discussed. Developmental trends of the photonics-based microwave IRM are also discussed.

Live Imaging of Shoot Meristems on an Inverted Confocal Microscope Using an Objective Lens Inverter Attachment

Science.gov (United States)

Nimchuk, Zachary L.; Perdue, Tony D.

2017-01-01

Live imaging of above ground meristems can lead to new insights in plant development not possible from static imaging of fixed tissue. The use of an upright confocal microscope offers several technical and biological advantages for live imaging floral or shoot meristems. However, many departments and core facilities possess only inverted confocal microscopes and lack the funding for an additional upright confocal microscope. Here we show that imaging of living apical meristems can be performed on existing inverted confocal microscopes with the use of an affordable and detachable InverterScope accessory. PMID:28579995

Live Imaging of Shoot Meristems on an Inverted Confocal Microscope Using an Objective Lens Inverter Attachment.

Science.gov (United States)

Nimchuk, Zachary L; Perdue, Tony D

2017-01-01

Live imaging of above ground meristems can lead to new insights in plant development not possible from static imaging of fixed tissue. The use of an upright confocal microscope offers several technical and biological advantages for live imaging floral or shoot meristems. However, many departments and core facilities possess only inverted confocal microscopes and lack the funding for an additional upright confocal microscope. Here we show that imaging of living apical meristems can be performed on existing inverted confocal microscopes with the use of an affordable and detachable InverterScope accessory.

Using Photoshop with images created by a confocal system.

Science.gov (United States)

Sedgewick, Jerry

2014-01-01

Many pure colors and grayscales tones that result from confocal imaging are not reproducible to output devices, such as printing presses, laptop projectors, and laser jet printers. Part of the difficulty in predicting the colors and tones that will reproduce lies in both the computer display, and in the display of unreproducible colors chosen for fluorophores. The use of a grayscale display for confocal channels and a LUT display to show saturated (clipped) tonal values aids visualization in the former instance and image integrity in the latter. Computer monitors used for post-processing in order to conform the image to the output device can be placed in darkened rooms, and the gamma for the display can be set to create darker shadow regions, and to control the display of color. These conditions aid in visualization of images so that blacks are set to grayer values that are more amenable to faithful reproduction. Preferences can be set in Photoshop for consistent display of colors, along with other settings to optimize use of memory. The Info window is opened so that tonal information can be shown via readouts. Images that are saved as indexed color are converted to grayscale or RGB Color, 16-bit is converted to 8-bit when desired, and colorized images from confocal software is returned to grayscale and re-colorized according to presented methods so that reproducible colors are made. Images may also be sharpened and noise may be reduced, or more than one image layered to show colocalization according to specific methods. Images are then converted to CMYK (Cyan, Magenta, Yellow and Black) for consequent assignment of pigment percentages for printing presses. Changes to single images and multiple images from image stacks are automated for efficient and consistent image processing changes. Some additional changes are done to those images destined for 3D visualization to better separate regions of interest from background. Files are returned to image stacks, saved and

Confocal scanning microscopy with multiple optical probes for high speed measurements and better imaging

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Chun, Wanhee; Lee, SeungWoo; Gweon, Dae-Gab

2008-02-01

Confocal scanning microscopy (CSM) needs a scanning mechanism because only one point information of specimen can be obtained. Therefore the speed of the confocal scanning microscopy is limited by the speed of the scanning tool. To overcome this limitation from scanning tool we propose another scanning mechanism. We make three optical probes in the specimen under confocal condition of each point. Three optical probes are moved by beam scanning mechanism with shared resonant scanning mirror (RM) and galvanometer driven mirror (GM). As each optical probe scan allocated region of the specimen, information from three points is obtained simultaneously and image acquisition time is reduced. Therefore confocal scanning microscopy with multiple optical probes is expected to have three times faster speed of the image acquisition than conventional one. And as another use, multiple optical probes to which different light wavelength is applied can scan whole same region respectively. It helps to obtain better contrast image in case of specimens having different optical characteristics for specific light wavelength. In conclusion confocal scanning microscopy with multiple optical probes is useful technique for views of image acquisition speed and image quality.

Microwave Imaging of Human Forearms: Pilot Study and Image Enhancement

Directory of Open Access Journals (Sweden)

Colin Gilmore

2013-01-01

Full Text Available We present a pilot study using a microwave tomography system in which we image the forearms of 5 adult male and female volunteers between the ages of 30 and 48. Microwave scattering data were collected at 0.8 to 1.2 GHz with 24 transmitting and receiving antennas located in a matching fluid of deionized water and table salt. Inversion of the microwave data was performed with a balanced version of the multiplicative-regularized contrast source inversion algorithm formulated using the finite-element method (FEM-CSI. T1-weighted MRI images of each volunteer’s forearm were also collected in the same plane as the microwave scattering experiment. Initial “blind” imaging results from the utilized inversion algorithm show that the image quality is dependent on the thickness of the arm’s peripheral adipose tissue layer; thicker layers of adipose tissue lead to poorer overall image quality. Due to the exible nature of the FEM-CSI algorithm used, prior information can be readily incorporated into the microwave imaging inversion process. We show that by introducing prior information into the FEM-CSI algorithm the internal anatomical features of all the arms are resolved, significantly improving the images. The prior information was estimated manually from the blind inversions using an ad hoc procedure.

Comparison of mouse mammary gland imaging techniques and applications: Reflectance confocal microscopy, GFP Imaging, and ultrasound

International Nuclear Information System (INIS)

Tilli, Maddalena T; Parrish, Angela R; Cotarla, Ion; Jones, Laundette P; Johnson, Michael D; Furth, Priscilla A

2008-01-01

Genetically engineered mouse models of mammary gland cancer enable the in vivo study of molecular mechanisms and signaling during development and cancer pathophysiology. However, traditional whole mount and histological imaging modalities are only applicable to non-viable tissue. We evaluated three techniques that can be quickly applied to living tissue for imaging normal and cancerous mammary gland: reflectance confocal microscopy, green fluorescent protein imaging, and ultrasound imaging. In the current study, reflectance confocal imaging offered the highest resolution and was used to optically section mammary ductal structures in the whole mammary gland. Glands remained viable in mammary gland whole organ culture when 1% acetic acid was used as a contrast agent. Our application of using green fluorescent protein expressing transgenic mice in our study allowed for whole mammary gland ductal structures imaging and enabled straightforward serial imaging of mammary gland ducts in whole organ culture to visualize the growth and differentiation process. Ultrasound imaging showed the lowest resolution. However, ultrasound was able to detect mammary preneoplastic lesions 0.2 mm in size and was used to follow cancer growth with serial imaging in living mice. In conclusion, each technique enabled serial imaging of living mammary tissue and visualization of growth and development, quickly and with minimal tissue preparation. The use of the higher resolution reflectance confocal and green fluorescent protein imaging techniques and lower resolution ultrasound were complementary

Portable oral cancer detection using a miniature confocal imaging probe with a large field of view

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Wang, Youmin; Raj, Milan; McGuff, H. Stan; Bhave, Gauri; Yang, Bin; Shen, Ting; Zhang, Xiaojing

2012-06-01

We demonstrate a MEMS micromirror enabled handheld confocal imaging probe for portable oral cancer detection, where a comparatively large field of view (FOV) was generated through the programmable Lissajous scanning pattern of the MEMS micromirror. Miniaturized handheld MEMS confocal imaging probe was developed, and further compared with the desktop confocal prototype under clinical setting. For the handheld confocal imaging system, optical design simulations using CODE VR® shows the lateral and axial resolution to be 0.98 µm and 4.2 µm, where experimental values were determined to be 3 µm and 5.8 µm, respectively, with a FOV of 280 µm×300 µm. Fast Lissajous imaging speed up to 2 fps was realized with improved Labview and Java based real-time imaging software. Properties such as 3D imaging through autofocusing and mosaic imaging for extended lateral view (6 mm × 8 mm) were examined for carcinoma real-time pathology. Neoplastic lesion tissues of giant cell fibroma and peripheral ossifying fibroma, the fibroma inside the paraffin box and ex vivo gross tissues were imaged by the bench-top and handheld imaging modalities, and further compared with commercial microscope imaging results. The MEMS scanner-based handheld confocal imaging probe shows great promise as a potential clinical tool for oral cancer diagnosis and treatment.

Portable oral cancer detection using a miniature confocal imaging probe with a large field of view

International Nuclear Information System (INIS)

Wang, Youmin; Raj, Milan; Bhave, Gauri; Yang, Bin; Zhang, Xiaojing; McGuff, H. Stan; Shen, Ting

2012-01-01

We demonstrate a MEMS micromirror enabled handheld confocal imaging probe for portable oral cancer detection, where a comparatively large field of view (FOV) was generated through the programmable Lissajous scanning pattern of the MEMS micromirror. Miniaturized handheld MEMS confocal imaging probe was developed, and further compared with the desktop confocal prototype under clinical setting. For the handheld confocal imaging system, optical design simulations using CODE V R® shows the lateral and axial resolution to be 0.98 µm and 4.2 µm, where experimental values were determined to be 3 µm and 5.8 µm, respectively, with a FOV of 280 µm×300 µm. Fast Lissajous imaging speed up to 2 fps was realized with improved Labview and Java based real-time imaging software. Properties such as 3D imaging through autofocusing and mosaic imaging for extended lateral view (6 mm × 8 mm) were examined for carcinoma real-time pathology. Neoplastic lesion tissues of giant cell fibroma and peripheral ossifying fibroma, the fibroma inside the paraffin box and ex vivo gross tissues were imaged by the bench-top and handheld imaging modalities, and further compared with commercial microscope imaging results. The MEMS scanner-based handheld confocal imaging probe shows great promise as a potential clinical tool for oral cancer diagnosis and treatment. (paper)

A Synthesizable Multicore Platform for Microwave Imaging

DEFF Research Database (Denmark)

Schleuniger, Pascal; Karlsson, Sven

2014-01-01

Active microwave imaging techniques such as radar and tomography are used in a wide range of medical, industrial, scientific, and military applications. Microwave imaging devices emit radio waves and process their reflections to reconstruct an image. However, data processing remains a challenge...

Parallel excitation-emission multiplexed fluorescence lifetime confocal microscopy for live cell imaging.

Science.gov (United States)

Zhao, Ming; Li, Yu; Peng, Leilei

2014-05-05

We present a novel excitation-emission multiplexed fluorescence lifetime microscopy (FLIM) method that surpasses current FLIM techniques in multiplexing capability. The method employs Fourier multiplexing to simultaneously acquire confocal fluorescence lifetime images of multiple excitation wavelength and emission color combinations at 44,000 pixels/sec. The system is built with low-cost CW laser sources and standard PMTs with versatile spectral configuration, which can be implemented as an add-on to commercial confocal microscopes. The Fourier lifetime confocal method allows fast multiplexed FLIM imaging, which makes it possible to monitor multiple biological processes in live cells. The low cost and compatibility with commercial systems could also make multiplexed FLIM more accessible to biological research community.

Chromatic confocal microscopy for multi-depth imaging of epithelial tissue

Science.gov (United States)

Olsovsky, Cory; Shelton, Ryan; Carrasco-Zevallos, Oscar; Applegate, Brian E.; Maitland, Kristen C.

2013-01-01

We present a novel chromatic confocal microscope capable of volumetric reflectance imaging of microstructure in non-transparent tissue. Our design takes advantage of the chromatic aberration of aspheric lenses that are otherwise well corrected. Strong chromatic aberration, generated by multiple aspheres, longitudinally disperses supercontinuum light onto the sample. The backscattered light detected with a spectrometer is therefore wavelength encoded and each spectrum corresponds to a line image. This approach obviates the need for traditional axial mechanical scanning techniques that are difficult to implement for endoscopy and susceptible to motion artifact. A wavelength range of 590-775 nm yielded a >150 µm imaging depth with ~3 µm axial resolution. The system was further demonstrated by capturing volumetric images of buccal mucosa. We believe these represent the first microstructural images in non-transparent biological tissue using chromatic confocal microscopy that exhibit long imaging depth while maintaining acceptable resolution for resolving cell morphology. Miniaturization of this optical system could bring enhanced speed and accuracy to endomicroscopic in vivo volumetric imaging of epithelial tissue. PMID:23667789

Fluorescence confocal microscopy for pathologists.

Science.gov (United States)

Ragazzi, Moira; Piana, Simonetta; Longo, Caterina; Castagnetti, Fabio; Foroni, Monica; Ferrari, Guglielmo; Gardini, Giorgio; Pellacani, Giovanni

2014-03-01

Confocal microscopy is a non-invasive method of optical imaging that may provide microscopic images of untreated tissue that correspond almost perfectly to hematoxylin- and eosin-stained slides. Nowadays, following two confocal imaging systems are available: (1) reflectance confocal microscopy, based on the natural differences in refractive indices of subcellular structures within the tissues; (2) fluorescence confocal microscopy, based on the use of fluorochromes, such as acridine orange, to increase the contrast epithelium-stroma. In clinical practice to date, confocal microscopy has been used with the goal of obviating the need for excision biopsies, thereby reducing the need for pathological examination. The aim of our study was to test fluorescence confocal microscopy on different types of surgical specimens, specifically breast, lymph node, thyroid, and colon. The confocal images were correlated to the corresponding histological sections in order to provide a morphologic parallel and to highlight current limitations and possible applications of this technology for surgical pathology practice. As a result, neoplastic tissues were easily distinguishable from normal structures and reactive processes such as fibrosis; the use of fluorescence enhanced contrast and image quality in confocal microscopy without compromising final histologic evaluation. Finally, the fluorescence confocal microscopy images of the adipose tissue were as accurate as those of conventional histology and were devoid of the frozen-section-related artefacts that can compromise intraoperative evaluation. Despite some limitations mainly related to black/white images, which require training in imaging interpretation, this study confirms that fluorescence confocal microscopy may represent an alternative to frozen sections in the assessment of margin status in selected settings or when the conservation of the specimen is crucial. This is the first study to employ fluorescent confocal microscopy on

Video-rate confocal microscopy for single-molecule imaging in live cells and superresolution fluorescence imaging.

Science.gov (United States)

Lee, Jinwoo; Miyanaga, Yukihiro; Ueda, Masahiro; Hohng, Sungchul

2012-10-17

There is no confocal microscope optimized for single-molecule imaging in live cells and superresolution fluorescence imaging. By combining the swiftness of the line-scanning method and the high sensitivity of wide-field detection, we have developed a, to our knowledge, novel confocal fluorescence microscope with a good optical-sectioning capability (1.0 μm), fast frame rates (fluorescence detection efficiency. Full compatibility of the microscope with conventional cell-imaging techniques allowed us to do single-molecule imaging with a great ease at arbitrary depths of live cells. With the new microscope, we monitored diffusion motion of fluorescently labeled cAMP receptors of Dictyostelium discoideum at both the basal and apical surfaces and obtained superresolution fluorescence images of microtubules of COS-7 cells at depths in the range 0-85 μm from the surface of a coverglass. Copyright © 2012 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Three-Dimensional Microwave Imaging for Indoor Environments

Science.gov (United States)

Scott, Simon

Microwave imaging involves the use of antenna arrays, operating at microwave and millimeter-wave frequencies, for capturing images of real-world objects. Typically, one or more antennas in the array illuminate the scene with a radio-frequency (RF) signal. Part of this signal reflects back to the other antennas, which record both the amplitude and phase of the reflected signal. These reflected RF signals are then processed to form an image of the scene. This work focuses on using planar antenna arrays, operating between 17 and 26 GHz, to capture three-dimensional images of people and other objects inside a room. Such an imaging system enables applications such as indoor positioning and tracking, health monitoring and hand gesture recognition. Microwave imaging techniques based on beamforming cannot be used for indoor imaging, as most objects lie within the array near-field. Therefore, the range-migration algorithm (RMA) is used instead, as it compensates for the curvature of the reflected wavefronts, hence enabling near-field imaging. It is also based on fast-Fourier transforms and is therefore computationally efficient. A number of novel RMA variants were developed to support a wider variety of antenna array configurations, as well as to generate 3-D velocity maps of objects moving around a room. The choice of antenna array configuration, microwave transceiver components and transmit power has a significant effect on both the energy consumed by the imaging system and the quality of the resulting images. A generic microwave imaging testbed was therefore built to characterize the effect of these antenna array parameters on image quality in the 20 GHz band. All variants of the RMA were compared and found to produce good quality three-dimensional images with transmit power levels as low as 1 muW. With an array size of 80x80 antennas, most of the imaging algorithms were able to image objects at 0.5 m range with 12.5 mm resolution, although some were only able to achieve

Ultrafast superresolution fluorescence imaging with spinning disk confocal microscope optics.

Science.gov (United States)

Hayashi, Shinichi; Okada, Yasushi

2015-05-01

Most current superresolution (SR) microscope techniques surpass the diffraction limit at the expense of temporal resolution, compromising their applications to live-cell imaging. Here we describe a new SR fluorescence microscope based on confocal microscope optics, which we name the spinning disk superresolution microscope (SDSRM). Theoretically, the SDSRM is equivalent to a structured illumination microscope (SIM) and achieves a spatial resolution of 120 nm, double that of the diffraction limit of wide-field fluorescence microscopy. However, the SDSRM is 10 times faster than a conventional SIM because SR signals are recovered by optical demodulation through the stripe pattern of the disk. Therefore a single SR image requires only a single averaged image through the rotating disk. On the basis of this theory, we modified a commercial spinning disk confocal microscope. The improved resolution around 120 nm was confirmed with biological samples. The rapid dynamics of micro-tubules, mitochondria, lysosomes, and endosomes were observed with temporal resolutions of 30-100 frames/s. Because our method requires only small optical modifications, it will enable an easy upgrade from an existing spinning disk confocal to a SR microscope for live-cell imaging. © 2015 Hayashi and Okada. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Confocal pore size measurement based on super-resolution image restoration.

Science.gov (United States)

Liu, Dali; Wang, Yun; Qiu, Lirong; Mao, Xinyue; Zhao, Weiqian

2014-09-01

A confocal pore size measurement based on super-resolution image restoration is proposed to obtain a fast and accurate measurement for submicrometer pore size of nuclear track-etched membranes (NTEMs). This method facilitates the online inspection of the pore size evolution during etching. Combining confocal microscopy with super-resolution image restoration significantly improves the lateral resolution of the NTEM image, yields a reasonable circle edge-setting criterion of 0.2408, and achieves precise pore edge detection. Theoretical analysis shows that the minimum measuring diameter can reach 0.19 μm, and the root mean square of the residuals is only 1.4 nm. Edge response simulation and experiment reveal that the edge response of the proposed method is better than 80 nm. The NTEM pore size measurement results obtained by the proposed method agree well with that obtained by scanning electron microscopy.

Experimental study of microwave-induced thermoacoustic imaging

Science.gov (United States)

Jacobs, Ryan T.

Microwave-Induced Thermoacoustic Imaging (TAI) is a noninvasive hybrid modality which improves contrast by using thermoelastic wave generation induced by microwave absorption. Ultrasonography is widely used in medical practice as a low-cost alternative and supplement to magnetic resonance imaging (MRI). Although ultrasonography has relatively high image resolution (depending on the ultrasonic wavelength at diagnostic frequencies), it suffers from low image contrast of soft tissues. In this work samples are irradiated with sub-microsecond electromagnetic pulses inducing acoustic waves in the sample that are then detected with an unfocused transducer. The advantage of this hybrid modality is the ability to take advantage of the microwave absorption coefficients which provide high contrast in tissue samples. This in combination with the superior spatial resolution of ultrasound waves is important to providing a low-cost alternative to MRI and early breast cancer detection methods. This work describes the implementation of a thermoacoustic experiment using a 5 kW peak power microwave source.

Multifocus confocal Raman microspectroscopy for fast multimode vibrational imaging of living cells.

Science.gov (United States)

Okuno, Masanari; Hamaguchi, Hiro-o

2010-12-15

We have developed a multifocus confocal Raman microspectroscopic system for the fast multimode vibrational imaging of living cells. It consists of an inverted microscope equipped with a microlens array, a pinhole array, a fiber bundle, and a multichannel Raman spectrometer. Forty-eight Raman spectra from 48 foci under the microscope are simultaneously obtained by using multifocus excitation and image-compression techniques. The multifocus confocal configuration suppresses the background generated from the cover glass and the cell culturing medium so that high-contrast images are obtainable with a short accumulation time. The system enables us to obtain multimode (10 different vibrational modes) vibrational images of living cells in tens of seconds with only 1 mW laser power at one focal point. This image acquisition time is more than 10 times faster than that in conventional single-focus Raman microspectroscopy.

Total Internal Reflection Fluorescence Microscopy Imaging-Guided Confocal Single-Molecule Fluorescence Spectroscopy

OpenAIRE

Zheng, Desheng; Kaldaras, Leonora; Lu, H. Peter

2013-01-01

We have developed an integrated spectroscopy system combining total internal reflection fluorescence microscopy imaging with confocal single-molecule fluorescence spectroscopy for two-dimensional interfaces. This spectroscopy approach is capable of both multiple molecules simultaneously sampling and in situ confocal fluorescence dynamics analyses of individual molecules of interest. We have demonstrated the calibration with fluorescent microspheres, and carried out single-molecule spectroscop...

Embryonic Heart Morphogenesis from Confocal Microscopy Imaging and Automatic Segmentation

Directory of Open Access Journals (Sweden)

Hongda Mao

2013-01-01

Full Text Available Embryonic heart morphogenesis (EHM is a complex and dynamic process where the heart transforms from a single tube into a four-chambered pump. This process is of great biological and clinical interest but is still poorly understood for two main reasons. On the one hand, the existing imaging modalities for investigating EHM suffered from either limited penetration depth or limited spatial resolution. On the other hand, current works typically adopted manual segmentation, which was tedious, subjective, and time consuming considering the complexity of developing heart geometry and the large size of images. In this paper, we propose to utilize confocal microscopy imaging with tissue optical immersion clearing technique to image the heart at different stages of development for EHM study. The imaging method is able to produce high spatial resolution images and achieve large penetration depth at the same time. Furthermore, we propose a novel convex active contour model for automatic image segmentation. The model has the ability to deal with intensity fall-off in depth which is characterized by confocal microscopy images. We acquired the images of embryonic quail hearts from day 6 to day 14 of incubation for EHM study. The experimental results were promising and provided us with an insight view of early heart growth pattern and also paved the road for data-driven heart growth modeling.

Line-scanning confocal microscopy for high-resolution imaging of upconverting rare-earth-based contrast agents

Science.gov (United States)

Higgins, Laura M.; Zevon, Margot; Ganapathy, Vidya; Sheng, Yang; Tan, Mei Chee; Riman, Richard E.; Roth, Charles M.; Moghe, Prabhas V.; Pierce, Mark C.

2015-01-01

Abstract. Rare-earth (RE) doped nanocomposites emit visible luminescence when illuminated with continuous wave near-infrared light, making them appealing candidates for use as contrast agents in biomedical imaging. However, the emission lifetime of these materials is much longer than the pixel dwell times used in scanning intravital microscopy. To overcome this limitation, we have developed a line-scanning confocal microscope for high-resolution, optically sectioned imaging of samples labeled with RE-based nanomaterials. Instrument performance is quantified using calibrated test objects. NaYF4:Er,Yb nanocomposites are imaged in vitro, and in ex vivo tissue specimens, with direct comparison to point-scanning confocal microscopy. We demonstrate that the extended pixel dwell time of line-scanning confocal microscopy enables subcellular-level imaging of these nanomaterials while maintaining optical sectioning. The line-scanning approach thus enables microscopic imaging of this emerging class of contrast agents for preclinical studies, with the potential to be adapted for real-time in vivo imaging in the clinic. PMID:26603495

Extended Field Laser Confocal Microscopy (EFLCM): Combining automated Gigapixel image capture with in silico virtual microscopy

International Nuclear Information System (INIS)

Flaberg, Emilie; Sabelström, Per; Strandh, Christer; Szekely, Laszlo

2008-01-01

Confocal laser scanning microscopy has revolutionized cell biology. However, the technique has major limitations in speed and sensitivity due to the fact that a single laser beam scans the sample, allowing only a few microseconds signal collection for each pixel. This limitation has been overcome by the introduction of parallel beam illumination techniques in combination with cold CCD camera based image capture. Using the combination of microlens enhanced Nipkow spinning disc confocal illumination together with fully automated image capture and large scale in silico image processing we have developed a system allowing the acquisition, presentation and analysis of maximum resolution confocal panorama images of several Gigapixel size. We call the method Extended Field Laser Confocal Microscopy (EFLCM). We show using the EFLCM technique that it is possible to create a continuous confocal multi-colour mosaic from thousands of individually captured images. EFLCM can digitize and analyze histological slides, sections of entire rodent organ and full size embryos. It can also record hundreds of thousands cultured cells at multiple wavelength in single event or time-lapse fashion on fixed slides, in live cell imaging chambers or microtiter plates. The observer independent image capture of EFLCM allows quantitative measurements of fluorescence intensities and morphological parameters on a large number of cells. EFLCM therefore bridges the gap between the mainly illustrative fluorescence microscopy and purely quantitative flow cytometry. EFLCM can also be used as high content analysis (HCA) instrument for automated screening processes

Assessment and Development of Microwave Imaging for Breast Cancer Detection

DEFF Research Database (Denmark)

Jensen, Peter Damsgaard

At the Technical University of Denmark (DTU), a 3D tomographic microwave imaging system is currently being developed with the aim of using nonlinear microwave imaging for breast-cancer detection. The imaging algorithm used in the system is based on an iterative Newton-type scheme. In this algorithm...... used in the microwave tomographic imaging system is presented. Non-linear microwave tomographic imaging of the breast is a challenging computational problem. The breast is heterogeneous and contains several high-contrast and lossy regions, resulting in large differences in the measured signal levels....... This implies that special care must be taken when the imaging problem is formulated. Under such conditions, microwave imaging systems will most often be considerably more sensitive to changes in the electromagnetic properties in certain regions of the breast. The result is that the parameters might...

Confocal imaging of butterfly tissue.

Science.gov (United States)

Brunetti, Craig R

2014-01-01

To understand the molecular events responsible for morphological change requires the ability to examine gene expression in a wide range of organisms in addition to model systems to determine how the differences in gene expression correlate with phenotypic differences. There are approximately 12,000 species of butterflies, most, with distinct patterns on their wings. The most important tool for studying gene expression in butterflies is confocal imaging of butterfly tissue by indirect immunofluorescence using either cross-reactive antibodies from closely related species such as Drosophila or developing butterfly-specific antibodies. In this report, we describe how indirect immunofluorescence protocols can be used to visualize protein expression patterns on the butterfly wing imaginal disc and butterfly embryo.

A novel method for enhancing the lateral resolution and image SNR in confocal microscopy

Science.gov (United States)

Chen, Youhua; Zhu, Dazhao; Fang, Yue; Kuang, Cuifang; Liu, Xu

2017-12-01

There is always a tradeoff between the resolution and the signal-to-noise ratio (SNR) in confocal microscopy. In particular, the pinhole size is very important for maintaining a balance between them. In this paper, we propose a method for improving the lateral resolution and image SNR in confocal microscopy without making any changes to the hardware. By using the fluorescence emission difference (FED) approach, we divide the images acquired by different pinhole sizes into one image acquired by the central pinhole and several images acquired by ring-shaped pinholes. Then, they are added together with the deconvolution method. Simulation and experimental results for fluorescent particles and cells show that our method can achieve a far better resolution than a large pinhole and a higher SNR than a small pinhole. Moreover, our method can improve the performance of classic confocal laser scanning microscopy (CLSM) to a certain extent, especially CLSM with a continuously variable pinhole.

Fibered Confocal Fluorescence Microscopy for the Noninvasive Imaging of Langerhans Cells in Macaques.

Science.gov (United States)

Todorova, Biliana; Salabert, Nina; Tricot, Sabine; Boisgard, Raphaël; Rathaux, Mélanie; Le Grand, Roger; Chapon, Catherine

2017-01-01

We developed a new approach to visualize skin Langerhans cells by in vivo fluorescence imaging in nonhuman primates. Macaques were intradermally injected with a monoclonal, fluorescently labeled antibody against HLA-DR molecule and were imaged for up to 5 days by fibered confocal microscopy (FCFM). The network of skin Langerhans cells was visualized by in vivo fibered confocal fluorescence microscopy. Quantification of Langerhans cells revealed no changes to cell density with time. Ex vivo experiments confirmed that injected fluorescent HLA-DR antibody specifically targeted Langerhans cells in the epidermis. This study demonstrates the feasibility of single-cell, in vivo imaging as a noninvasive technique to track Langerhans cells in nontransgenic animals.

Confocal stereology and image analysis: methods for estimating geometrical characteristics of cells and tissues from three-dimensional confocal images

Czech Academy of Sciences Publication Activity Database

Kubínová, Lucie; Janáček, Jiří; Karen, Petr; Radochová, Barbora; Difato, Francesco; Krekule, Ivan

2004-01-01

Roč. 53, Suppl.1 (2004), s. S47-S55 ISSN 0862-8408 R&D Projects: GA ČR GA304/01/0257; GA ČR GA310/02/1470; GA AV ČR KJB6011309; GA AV ČR KJB5039302 Grant - others:SI - CZ(CZ) KONTAKT 001/2001 Institutional research plan: CEZ:AV0Z5011922 Keywords : confocal microscopy * image analysis * stereology Subject RIV: EA - Cell Biology Impact factor: 1.140, year: 2004

3D Imaging of Porous Media Using Laser Scanning Confocal Microscopy with Application to Microscale Transport Processes

Energy Technology Data Exchange (ETDEWEB)

Fredrich, J.T.

1999-02-10

We present advances in the application of laser scanning confocal microscopy (LSCM) to image, reconstruct, and characterize statistically the microgeometry of porous geologic and engineering materials. We discuss technical and practical aspects of this imaging technique, including both its advantages and limitations. Confocal imaging can be used to optically section a material, with sub-micron resolution possible in the lateral and axial planes. The resultant volumetric image data, consisting of fluorescence intensities for typically {approximately}50 million voxels in XYZ space, can be used to reconstruct the three-dimensional structure of the two-phase medium. We present several examples of this application, including studying pore geometry in sandstone, characterizing brittle failure processes in low-porosity rock deformed under triaxial loading conditions in the laboratory, and analyzing the microstructure of porous ceramic insulations. We then describe approaches to extract statistical microgeometric descriptions from volumetric image data, and present results derived from confocal volumetric data sets. Finally, we develop the use of confocal image data to automatically generate a three-dimensional mesh for numerical pore-scale flow simulations.

Improvement in volume estimation from confocal sections after image deconvolution

Czech Academy of Sciences Publication Activity Database

Difato, Francesco; Mazzone, F.; Scaglione, S.; Fato, M.; Beltrame, F.; Kubínová, Lucie; Janáček, Jiří; Ramoino, P.; Vicidomini, G.; Diaspro, A.

2004-01-01

Roč. 64, č. 2 (2004), s. 151-155 ISSN 1059-910X Institutional research plan: CEZ:AV0Z5011922 Keywords : confocal microscopy * image deconvolution * point spread function Subject RIV: EA - Cell Biology Impact factor: 2.609, year: 2004

A comparison of image restoration approaches applied to three-dimensional confocal and wide-field fluorescence microscopy.

Science.gov (United States)

Verveer, P. J; Gemkow, M. J; Jovin, T. M

1999-01-01

We have compared different image restoration approaches for fluorescence microscopy. The most widely used algorithms were classified with a Bayesian theory according to the assumed noise model and the type of regularization imposed. We considered both Gaussian and Poisson models for the noise in combination with Tikhonov regularization, entropy regularization, Good's roughness and without regularization (maximum likelihood estimation). Simulations of fluorescence confocal imaging were used to examine the different noise models and regularization approaches using the mean squared error criterion. The assumption of a Gaussian noise model yielded only slightly higher errors than the Poisson model. Good's roughness was the best choice for the regularization. Furthermore, we compared simulated confocal and wide-field data. In general, restored confocal data are superior to restored wide-field data, but given sufficient higher signal level for the wide-field data the restoration result may rival confocal data in quality. Finally, a visual comparison of experimental confocal and wide-field data is presented.

3-D reconstruction of neurons from multichannel confocal laser scanning image series.

Science.gov (United States)

Wouterlood, Floris G

2014-04-10

A confocal laser scanning microscope (CLSM) collects information from a thin, focal plane and ignores out-of-focus information. Scanning of a specimen, with stepwise axial (Z-) movement of the stage in between each scan, produces Z-series of confocal images of a tissue volume, which then can be used to 3-D reconstruct structures of interest. The operator first configures separate channels (e.g., laser, filters, and detector settings) for each applied fluorochrome and then acquires Z-series of confocal images: one series per channel. Channel signal separation is extremely important. Measures to avoid bleaching are vital. Post-acquisition deconvolution of the image series is often performed to increase resolution before 3-D reconstruction takes place. In the 3-D reconstruction programs described in this unit, reconstructions can be inspected in real time from any viewing angle. By altering viewing angles and by switching channels off and on, the spatial relationships of 3-D-reconstructed structures with respect to structures visualized in other channels can be studied. Since each brand of CLSM, computer program, and 3-D reconstruction package has its own proprietary set of procedures, a general approach is provided in this protocol wherever possible. Copyright © 2014 John Wiley & Sons, Inc.

TRMM MICROWAVE IMAGER (TMI) WENTZ OCEAN PRODUCTS V3

Data.gov (United States)

National Aeronautics and Space Administration — The TRMM Microwave Imager (TMI) is a 5-channel, dual-polarized, passive microwave radiometer. Microwave radiation is emitted by the Earth's surface and by water...

Prototype of Microwave Imaging System for Breast-Cancer Screening

DEFF Research Database (Denmark)

Rubæk, Tonny; Zhurbenko, Vitaliy

2009-01-01

Microwave imaging for breast-cancer detection has received the attention of a large number of research groups in the last decade. In this paper, the imaging system currently being developed at the Technical university of Denmark is presented. This includes a description of the antenna system......, the microwave hardware, and the imaging algorithm....

Microwave SQUID Multiplexer Demonstration for Cosmic Microwave Background Imagers.

Science.gov (United States)

Dober, B; Becker, D T; Bennett, D A; Bryan, S A; Duff, S M; Gard, J D; Hays-Wehle, J P; Hilton, G C; Hubmayr, J; Mates, J A B; Reintsema, C D; Vale, L R; Ullom, J N

2017-12-01

Key performance characteristics are demonstrated for the microwave SQUID multiplexer (µmux) coupled to transition edge sensor (TES) bolometers that have been optimized for cosmic microwave background (CMB) observations. In a 64-channel demonstration, we show that the µmux produces a white, input referred current noise level of [Formula: see text] at -77 dB microwave probe tone power, which is well below expected fundamental detector and photon noise sources for a ground-based CMB-optimized bolometer. Operated with negligible photon loading, we measure [Formula: see text] in the TES-coupled channels biased at 65% of the sensor normal resistance. This noise level is consistent with that predicted from bolometer thermal fluctuation (i.e. phonon) noise. Furthermore, the power spectral density is white over a range of frequencies down to ~ 100 mHz, which enables CMB mapping on large angular scales that constrain the physics of inflation. Additionally, we report cross-talk measurements that indicate a level below 0.3%, which is less than the level of cross-talk from multiplexed readout systems in deployed CMB imagers. These measurements demonstrate the µmux as a viable readout technique for future CMB imaging instruments.

3D confocal imaging in CUBIC-cleared mouse heart

Energy Technology Data Exchange (ETDEWEB)

Nehrhoff, I.; Bocancea, D.; Vaquero, J.; Vaquero, J.J.; Lorrio, M.T.; Ripoll, J.; Desco, M.; Gomez-Gaviro, M.V.

2016-07-01

Acquiring high resolution 3D images of the heart enables the ability to study heart diseases more in detail. Here, the CUBIC (clear, unobstructed brain imaging cocktails and computational analysis) clearing protocol was adapted for thick mouse heart sections to increase the penetration depth of the confocal microscope lasers into the tissue. The adapted CUBIC clearing of the heart lets the antibody penetrate deeper into the tissue by a factor of five. The here shown protocol enables deep 3D highresolution image acquisition in the heart. This allows a much more accurate assessment of the cellular and structural changes that underlie heart diseases. (Author)

3D confocal imaging in CUBIC-cleared mouse heart

International Nuclear Information System (INIS)

Nehrhoff, I.; Bocancea, D.; Vaquero, J.; Vaquero, J.J.; Lorrio, M.T.; Ripoll, J.; Desco, M.; Gomez-Gaviro, M.V.

2016-01-01

Acquiring high resolution 3D images of the heart enables the ability to study heart diseases more in detail. Here, the CUBIC (clear, unobstructed brain imaging cocktails and computational analysis) clearing protocol was adapted for thick mouse heart sections to increase the penetration depth of the confocal microscope lasers into the tissue. The adapted CUBIC clearing of the heart lets the antibody penetrate deeper into the tissue by a factor of five. The here shown protocol enables deep 3D highresolution image acquisition in the heart. This allows a much more accurate assessment of the cellular and structural changes that underlie heart diseases. (Author)

Tissue clearing for confocal imaging of native and bio-artificial skeletal muscle.

Science.gov (United States)

Decroix, L; Van Muylder, V; Desender, L; Sampaolesi, M; Thorrez, L

2015-01-01

Novel clearing techniques have revolutionized three-dimensional confocal imaging of the brain without the need for physical tissue sectioning. We evaluated three clearing methods, ScaleA2, Clear(T2), and 3DISCO for visualizing native and tissue engineered muscle by confocal microscopy. We found that Clear(T2) treatment improved the depth of visualization of immunohistochemical staining slightly, but did not improve depth of visualization of endogenous green fluorescent protein (GFP). ScaleA2 preserved endogenous GFP signal better and permitted significantly deeper GFP imaging, but it was incompatible with tropomyosin immunohistochemical staining. 3DISCO treatment preserved both endogenous GFP and immunohistochemical staining, and permitted significantly deeper imaging. Clearing time for the 3DISCO procedure is short compared to ScaleA2 and Clear(T2). We suggest that 3DISCO is the preferable clearing method for native and tissue engineered skeletal muscle tissue.

Ribbon scanning confocal for high-speed high-resolution volume imaging of brain.

Directory of Open Access Journals (Sweden)

Alan M Watson

Full Text Available Whole-brain imaging is becoming a fundamental means of experimental insight; however, achieving subcellular resolution imagery in a reasonable time window has not been possible. We describe the first application of multicolor ribbon scanning confocal methods to collect high-resolution volume images of chemically cleared brains. We demonstrate that ribbon scanning collects images over ten times faster than conventional high speed confocal systems but with equivalent spectral and spatial resolution. Further, using this technology, we reconstruct large volumes of mouse brain infected with encephalitic alphaviruses and demonstrate that regions of the brain with abundant viral replication were inaccessible to vascular perfusion. This reveals that the destruction or collapse of large regions of brain micro vasculature may contribute to the severe disease caused by Venezuelan equine encephalitis virus. Visualization of this fundamental impact of infection would not be possible without sampling at subcellular resolution within large brain volumes.

RELIABILITY OF CONFOCAL MICROSCOPY SPECTRAL IMAGING SYSTEMS: USE OF MULTISPECTRAL BEADS

Science.gov (United States)

Background: There is a need for a standardized, impartial calibration, and validation protocol on confocal spectral imaging (CSI) microscope systems. To achieve this goal, it is necessary to have testing tools to provide a reproducible way to evaluate instrument performance. ...

Using x-ray mammograms to assist in microwave breast image interpretation.

Science.gov (United States)

Curtis, Charlotte; Frayne, Richard; Fear, Elise

2012-01-01

Current clinical breast imaging modalities include ultrasound, magnetic resonance (MR) imaging, and the ubiquitous X-ray mammography. Microwave imaging, which takes advantage of differing electromagnetic properties to obtain image contrast, shows potential as a complementary imaging technique. As an emerging modality, interpretation of 3D microwave images poses a significant challenge. MR images are often used to assist in this task, and X-ray mammograms are readily available. However, X-ray mammograms provide 2D images of a breast under compression, resulting in significant geometric distortion. This paper presents a method to estimate the 3D shape of the breast and locations of regions of interest from standard clinical mammograms. The technique was developed using MR images as the reference 3D shape with the future intention of using microwave images. Twelve breast shapes were estimated and compared to ground truth MR images, resulting in a skin surface estimation accurate to within an average Euclidean distance of 10 mm. The 3D locations of regions of interest were estimated to be within the same clinical area of the breast as corresponding regions seen on MR imaging. These results encourage investigation into the use of mammography as a source of information to assist with microwave image interpretation as well as validation of microwave imaging techniques.

Confocal non-line-of-sight imaging based on the light-cone transform

Science.gov (United States)

O’Toole, Matthew; Lindell, David B.; Wetzstein, Gordon

2018-03-01

How to image objects that are hidden from a camera’s view is a problem of fundamental importance to many fields of research, with applications in robotic vision, defence, remote sensing, medical imaging and autonomous vehicles. Non-line-of-sight (NLOS) imaging at macroscopic scales has been demonstrated by scanning a visible surface with a pulsed laser and a time-resolved detector. Whereas light detection and ranging (LIDAR) systems use such measurements to recover the shape of visible objects from direct reflections, NLOS imaging reconstructs the shape and albedo of hidden objects from multiply scattered light. Despite recent advances, NLOS imaging has remained impractical owing to the prohibitive memory and processing requirements of existing reconstruction algorithms, and the extremely weak signal of multiply scattered light. Here we show that a confocal scanning procedure can address these challenges by facilitating the derivation of the light-cone transform to solve the NLOS reconstruction problem. This method requires much smaller computational and memory resources than previous reconstruction methods do and images hidden objects at unprecedented resolution. Confocal scanning also provides a sizeable increase in signal and range when imaging retroreflective objects. We quantify the resolution bounds of NLOS imaging, demonstrate its potential for real-time tracking and derive efficient algorithms that incorporate image priors and a physically accurate noise model. Additionally, we describe successful outdoor experiments of NLOS imaging under indirect sunlight.

Spectral imaging technique for retinal perfusion detection using confocal scanning laser ophthalmoscopy

Science.gov (United States)

Rasta, Seyed Hossein; Manivannan, Ayyakkannu; Sharp, Peter F.

2012-11-01

To evaluate retinal perfusion in the human eye, a dual-wavelength confocal scanning laser ophthalmoscope (cSLO) was developed that provides spectral imaging of the fundus using a combination of red (670 nm) and near-infrared (810 nm) wavelengths. The image of the ocular fundus was analyzed to find out if quantitative measurements of the reflectivity of tissue permit assessment of the oxygen perfusion of tissue. We explored problems that affect the reproducibility of patient measurements such as non-uniformity errors on the image. For the first time, an image processing technique was designed and used to minimize the errors of oxygen saturation measurements by illumination correction in retina wide field by increasing SNR. Retinal images were taken from healthy and diabetic retinopathy eyes using the cSLO with a confocal aperture of 100 μm. The ratio image (RI) of red/IR, as oxygen saturation (SO2) index, was calculated for normal eyes. The image correction technique improved the reproducibility of the measurements. Average RI intensity variation of healthy retina tissue was determined within a range of about 5.5%. The capability of the new technique to discriminate oxygenation levels of retinal artery and vein was successfully demonstrated and showed good promise in the diagnosis of the perfused retina.

Microwave SQUID multiplexer demonstration for cosmic microwave background imagers

Science.gov (United States)

Dober, B.; Becker, D. T.; Bennett, D. A.; Bryan, S. A.; Duff, S. M.; Gard, J. D.; Hays-Wehle, J. P.; Hilton, G. C.; Hubmayr, J.; Mates, J. A. B.; Reintsema, C. D.; Vale, L. R.; Ullom, J. N.

2017-12-01

Key performance characteristics are demonstrated for the microwave superconducting quantum interference device (SQUID) multiplexer (μmux) coupled to transition edge sensor (TES) bolometers that have been optimized for cosmic microwave background (CMB) observations. In a 64-channel demonstration, we show that the μmux produces a white, input referred current noise level of 29 pA/ √{H z } at a microwave probe tone power of -77 dB, which is well below the expected fundamental detector and photon noise sources for a ground-based CMB-optimized bolometer. Operated with negligible photon loading, we measure 98 pA/ √{H z } in the TES-coupled channels biased at 65% of the sensor normal resistance. This noise level is consistent with that predicted from bolometer thermal fluctuation (i.e., phonon) noise. Furthermore, the power spectral density is white over a range of frequencies down to ˜100 mHz, which enables CMB mapping on large angular scales that constrain the physics of inflation. Additionally, we report cross-talk measurements that indicate a level below 0.3%, which is less than the level of cross-talk from multiplexed readout systems in deployed CMB imagers. These measurements demonstrate the μmux as a viable readout technique for future CMB imaging instruments.

Quantification of Confocal Images Using LabVIEW for Tissue Engineering Applications.

Science.gov (United States)

Sfakis, Lauren; Kamaldinov, Tim; Larsen, Melinda; Castracane, James; Khmaladze, Alexander

2016-11-01

Quantifying confocal images to enable location of specific proteins of interest in three-dimensional (3D) is important for many tissue engineering (TE) applications. Quantification of protein localization is essential for evaluation of specific scaffold constructs for cell growth and differentiation for application in TE and tissue regeneration strategies. Although obtaining information regarding protein expression levels is important, the location of proteins within cells grown on scaffolds is often the key to evaluating scaffold efficacy. Functional epithelial cell monolayers must be organized with apicobasal polarity with proteins specifically localized to the apical or basolateral regions of cells in many organs. In this work, a customized program was developed using the LabVIEW platform to quantify protein positions in Z-stacks of confocal images of epithelial cell monolayers. The program's functionality is demonstrated through salivary gland TE, since functional salivary epithelial cells must correctly orient many proteins on the apical and basolateral membranes. Bio-LabVIEW Image Matrix Evaluation (Bio-LIME) takes 3D information collected from confocal Z-stack images and processes the fluorescence at each pixel to determine cell heights, nuclei heights, nuclei widths, protein localization, and cell count. As a demonstration of its utility, Bio-LIME was used to quantify the 3D location of the Zonula occludens-1 protein contained within tight junctions and its change in 3D position in response to chemical modification of the scaffold with laminin. Additionally, Bio-LIME was used to demonstrate that there is no advantage of sub-100 nm poly lactic-co-glycolic acid nanofibers over 250 nm fibers for epithelial apicobasal polarization. Bio-LIME will be broadly applicable for quantification of proteins in 3D that are grown in many different contexts.

Using X-Ray Mammograms to Assist in Microwave Breast Image Interpretation

Directory of Open Access Journals (Sweden)

Charlotte Curtis

2012-01-01

Full Text Available Current clinical breast imaging modalities include ultrasound, magnetic resonance (MR imaging, and the ubiquitous X-ray mammography. Microwave imaging, which takes advantage of differing electromagnetic properties to obtain image contrast, shows potential as a complementary imaging technique. As an emerging modality, interpretation of 3D microwave images poses a significant challenge. MR images are often used to assist in this task, and X-ray mammograms are readily available. However, X-ray mammograms provide 2D images of a breast under compression, resulting in significant geometric distortion. This paper presents a method to estimate the 3D shape of the breast and locations of regions of interest from standard clinical mammograms. The technique was developed using MR images as the reference 3D shape with the future intention of using microwave images. Twelve breast shapes were estimated and compared to ground truth MR images, resulting in a skin surface estimation accurate to within an average Euclidean distance of 10 mm. The 3D locations of regions of interest were estimated to be within the same clinical area of the breast as corresponding regions seen on MR imaging. These results encourage investigation into the use of mammography as a source of information to assist with microwave image interpretation as well as validation of microwave imaging techniques.

Anatomical and metabolic small-animal whole-body imaging using ring-shaped confocal photoacoustic computed tomography

Science.gov (United States)

Xia, Jun; Chatni, Muhammad; Maslov, Konstantin; Wang, Lihong V.

2013-03-01

Due to the wide use of animals for human disease studies, small animal whole-body imaging plays an increasingly important role in biomedical research. Currently, none of the existing imaging modalities can provide both anatomical and glucose metabolic information, leading to higher costs of building dual-modality systems. Even with image coregistration, the spatial resolution of the metabolic imaging modality is not improved. We present a ring-shaped confocal photoacoustic computed tomography (RC-PACT) system that can provide both assessments in a single modality. Utilizing the novel design of confocal full-ring light delivery and ultrasound transducer array detection, RC-PACT provides full-view cross-sectional imaging with high spatial resolution. Scanning along the orthogonal direction provides three-dimensional imaging. While the mouse anatomy was imaged with endogenous hemoglobin contrast, the glucose metabolism was imaged with a near-infrared dye-labeled 2-deoxyglucose. Through mouse tumor models, we demonstrate that RC-PACT may be a paradigm shifting imaging method for preclinical research.

An introduction to microwave imaging for breast cancer detection

CERN Document Server

Conceição, Raquel Cruz; O'Halloran, Martin

2016-01-01

This book collates past and current research on one of the most promising emerging modalities for breast cancer detection. Readers will discover how, as a standalone technology or in conjunction with another modality, microwave imaging has the potential to provide reliable, safe and comfortable breast exams at low cost. Current breast imaging modalities include X- ray, Ultrasound, Magnetic Resonance Imaging, and Positron Emission Tomography. Each of these methods suffers from limitations, including poor sensitivity or specificity, high cost, patient discomfort, and exposure to potentially harmful ionising radiation. Microwave breast imaging is based on a contrast in the dielectric properties of breast tissue that exists at microwave frequencies. The book begins by considering the anatomy and dielectric properties of the breast, contrasting historical and recent studies. Next, radar-based breast imaging algorithms are discussed, encompassing both early-stage artefact removal, and data independent and adaptive ...

Semiautomated confocal imaging of fungal pathogenesis on plants: Microscopic analysis of macroscopic specimens.

Science.gov (United States)

Minker, Katharine R; Biedrzycki, Meredith L; Kolagunda, Abhishek; Rhein, Stephen; Perina, Fabiano J; Jacobs, Samuel S; Moore, Michael; Jamann, Tiffany M; Yang, Qin; Nelson, Rebecca; Balint-Kurti, Peter; Kambhamettu, Chandra; Wisser, Randall J; Caplan, Jeffrey L

2018-02-01

The study of phenotypic variation in plant pathogenesis provides fundamental information about the nature of disease resistance. Cellular mechanisms that alter pathogenesis can be elucidated with confocal microscopy; however, systematic phenotyping platforms-from sample processing to image analysis-to investigate this do not exist. We have developed a platform for 3D phenotyping of cellular features underlying variation in disease development by fluorescence-specific resolution of host and pathogen interactions across time (4D). A confocal microscopy phenotyping platform compatible with different maize-fungal pathosystems (fungi: Setosphaeria turcica, Cochliobolus heterostrophus, and Cercospora zeae-maydis) was developed. Protocols and techniques were standardized for sample fixation, optical clearing, species-specific combinatorial fluorescence staining, multisample imaging, and image processing for investigation at the macroscale. The sample preparation methods presented here overcome challenges to fluorescence imaging such as specimen thickness and topography as well as physiological characteristics of the samples such as tissue autofluorescence and presence of cuticle. The resulting imaging techniques provide interesting qualitative and quantitative information not possible with conventional light or electron 2D imaging. Microsc. Res. Tech., 81:141-152, 2018. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Challenges in the Design of Microwave Imaging Systems for Breast Cancer Detection

DEFF Research Database (Denmark)

Zhurbenko, Vitaliy

2011-01-01

community. This paper presents the survey of the ongoing research in the field of microwave imaging of biological tissues, with major focus on the breast tumor detection application. The existing microwave imaging systems are categorized on the basis of the employed measurement concepts. The advantages......Among the various breast imaging modalities for breast cancer detection, microwave imaging is attractive due to the high contrast in dielectric properties between the cancerous and normal tissue. Due to this reason, this modality has received a significant interest and attention from the microwave...... and disadvantages of the implemented imaging techniques are discussed. The fundamental tradeoffs between the various system requirements are indicated. Some strategies to overcome these limitations are outlined....

Dynamic metamaterial aperture for microwave imaging

International Nuclear Information System (INIS)

Sleasman, Timothy; Imani, Mohammadreza F.; Gollub, Jonah N.; Smith, David R.

2015-01-01

We present a dynamic metamaterial aperture for use in computational imaging schemes at microwave frequencies. The aperture consists of an array of complementary, resonant metamaterial elements patterned into the upper conductor of a microstrip line. Each metamaterial element contains two diodes connected to an external control circuit such that the resonance of the metamaterial element can be damped by application of a bias voltage. Through applying different voltages to the control circuit, select subsets of the elements can be switched on to create unique radiation patterns that illuminate the scene. Spatial information of an imaging domain can thus be encoded onto this set of radiation patterns, or measurements, which can be processed to reconstruct the targets in the scene using compressive sensing algorithms. We discuss the design and operation of a metamaterial imaging system and demonstrate reconstructed images with a 10:1 compression ratio. Dynamic metamaterial apertures can potentially be of benefit in microwave or millimeter wave systems such as those used in security screening and through-wall imaging. In addition, feature-specific or adaptive imaging can be facilitated through the use of the dynamic aperture

Dynamic metamaterial aperture for microwave imaging

Energy Technology Data Exchange (ETDEWEB)

Sleasman, Timothy; Imani, Mohammadreza F.; Gollub, Jonah N.; Smith, David R. [Center for Metamaterials and Integrated Plasmonics, Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina, 27708 (United States)

2015-11-16

We present a dynamic metamaterial aperture for use in computational imaging schemes at microwave frequencies. The aperture consists of an array of complementary, resonant metamaterial elements patterned into the upper conductor of a microstrip line. Each metamaterial element contains two diodes connected to an external control circuit such that the resonance of the metamaterial element can be damped by application of a bias voltage. Through applying different voltages to the control circuit, select subsets of the elements can be switched on to create unique radiation patterns that illuminate the scene. Spatial information of an imaging domain can thus be encoded onto this set of radiation patterns, or measurements, which can be processed to reconstruct the targets in the scene using compressive sensing algorithms. We discuss the design and operation of a metamaterial imaging system and demonstrate reconstructed images with a 10:1 compression ratio. Dynamic metamaterial apertures can potentially be of benefit in microwave or millimeter wave systems such as those used in security screening and through-wall imaging. In addition, feature-specific or adaptive imaging can be facilitated through the use of the dynamic aperture.

4Pi-confocal microscopy of live cells

Science.gov (United States)

Bahlmann, Karsten; Jakobs, Stefan; Hell, Stefan W.

2002-06-01

By coherently adding the spherical wavefronts of two opposing lenses, two-photon excitation 4Pi-confocal fluorescence microscopy has achieved three-dimensional imaging with an axial resolution 3-7 times better than confocal microscopy. So far this improvement was possible only in glycerol-mounted, fixed cells. Here we report 4Pi-confocal microscopy of watery objects and its application to the imaging of live cells. Water immersion 4Pi-confocal microscopy of membrane stained live Escherichia coli bacteria attains a 4.3 fold better axial resolution as compared to the best water immersion confocal microscope. The resolution enhancement results into a vastly improved three-dimensional representation of the bacteria. The first images of live biological samples with an all-directional resolution in the 190-280 nm range are presented here, thus establishing a new resolution benchmark in live cell microscopy.

Microwave non-contact imaging of subcutaneous human body tissues.

Science.gov (United States)

Kletsov, Andrey; Chernokalov, Alexander; Khripkov, Alexander; Cho, Jaegeol; Druchinin, Sergey

2015-10-01

A small-size microwave sensor is developed for non-contact imaging of a human body structure in 2D, enabling fitness and health monitoring using mobile devices. A method for human body tissue structure imaging is developed and experimentally validated. Subcutaneous fat tissue reconstruction depth of up to 70 mm and maximum fat thickness measurement error below 2 mm are demonstrated by measurements with a human body phantom and human subjects. Electrically small antennas are developed for integration of the microwave sensor into a mobile device. Usability of the developed microwave sensor for fitness applications, healthcare, and body weight management is demonstrated.

Dual filtered backprojection for micro-rotation confocal microscopy

International Nuclear Information System (INIS)

Laksameethanasan, Danai; Brandt, Sami S; Renaud, Olivier; Shorte, Spencer L

2009-01-01

Micro-rotation confocal microscopy is a novel optical imaging technique which employs dielectric fields to trap and rotate individual cells to facilitate 3D fluorescence imaging using a confocal microscope. In contrast to computed tomography (CT) where an image can be modelled as parallel projection of an object, the ideal confocal image is recorded as a central slice of the object corresponding to the focal plane. In CT, the projection images and the 3D object are related by the Fourier slice theorem which states that the Fourier transform of a CT image is equal to the central slice of the Fourier transform of the 3D object. In the micro-rotation application, we have a dual form of this setting, i.e. the Fourier transform of the confocal image equals the parallel projection of the Fourier transform of the 3D object. Based on the observed duality, we present here the dual of the classical filtered back projection (FBP) algorithm and apply it in micro-rotation confocal imaging. Our experiments on real data demonstrate that the proposed method is a fast and reliable algorithm for the micro-rotation application, as FBP is for CT application

A principal skeleton algorithm for standardizing confocal images of fruit fly nervous systems

Science.gov (United States)

Qu, Lei; Peng, Hanchuan

2010-01-01

Motivation: The fruit fly (Drosophila melanogaster) is a commonly used model organism in biology. We are currently building a 3D digital atlas of the fruit fly larval nervous system (LNS) based on a large collection of fly larva GAL4 lines, each of which targets a subset of neurons. To achieve such a goal, we need to automatically align a number of high-resolution confocal image stacks of these GAL4 lines. One commonly employed strategy in image pattern registration is to first globally align images using an affine transform, followed by local non-linear warping. Unfortunately, the spatially articulated and often twisted LNS makes it difficult to globally align the images directly using the affine method. In a parallel project to build a 3D digital map of the adult fly ventral nerve cord (VNC), we are confronted with a similar problem. Results: We proposed to standardize a larval image by best aligning its principal skeleton (PS), and thus used this method as an alternative of the usually considered affine alignment. The PS of a shape was defined as a series of connected polylines that spans the entire shape as broadly as possible, but with the shortest overall length. We developed an automatic PS detection algorithm to robustly detect the PS from an image. Then for a pair of larval images, we designed an automatic image registration method to align their PSs and the entire images simultaneously. Our experimental results on both simulated images and real datasets showed that our method does not only produce satisfactory results for real confocal larval images, but also perform robustly and consistently when there is a lot of noise in the data. We also applied this method successfully to confocal images of some other patterns such as the adult fruit fly VNC and center brain, which have more complicated PS. This demonstrates the flexibility and extensibility of our method. Availability: The supplementary movies, full size figures, test data, software, and tutorial on

In vitro confocal imaging of the rabbit cornea.

Science.gov (United States)

Masters, B R; Paddock, S

1990-05-01

We were able to observe in vitro the fine structure of the rabbit cornea using a laser scanning confocal microscope, especially in the regions between Descemet's membrane and the epithelial basal lamina. We observed submicrometre filaments throughout the stroma with high concentrations adjacent to Descemet's membrane, and found extensive interconnecting processes between stromal keratocytes. There are numerous regions containing nerve plexuses in the stroma. We found a deeply convoluted basal lamina adjacent to the epithelium, and observed regions containing junctions between endothelial cells in fluorescent images of rabbit corneas stained with the actin-specific compound fluorescein phalloidin.

3D image restoration for confocal microscopy: toward a wavelet deconvolution for the study of complex biological structures

Science.gov (United States)

Boutet de Monvel, Jacques; Le Calvez, Sophie; Ulfendahl, Mats

2000-05-01

Image restoration algorithms provide efficient tools for recovering part of the information lost in the imaging process of a microscope. We describe recent progress in the application of deconvolution to confocal microscopy. The point spread function of a Biorad-MRC1024 confocal microscope was measured under various imaging conditions, and used to process 3D-confocal images acquired in an intact preparation of the inner ear developed at Karolinska Institutet. Using these experiments we investigate the application of denoising methods based on wavelet analysis as a natural regularization of the deconvolution process. Within the Bayesian approach to image restoration, we compare wavelet denoising with the use of a maximum entropy constraint as another natural regularization method. Numerical experiments performed with test images show a clear advantage of the wavelet denoising approach, allowing to `cool down' the image with respect to the signal, while suppressing much of the fine-scale artifacts appearing during deconvolution due to the presence of noise, incomplete knowledge of the point spread function, or undersampling problems. We further describe a natural development of this approach, which consists of performing the Bayesian inference directly in the wavelet domain.

A method for analysis of lipid vesicle domain structure from confocal image data

DEFF Research Database (Denmark)

Husen, Peter Rasmussen; Fidorra, Matthias; Hartel, Steffen

2012-01-01

Quantitative characterization of the lateral structure of curved membranes based on fluorescence microscopy requires knowledge of the fluorophore distribution on the surface. We present an image analysis approach for extraction of the fluorophore distribution on a spherical lipid vesicle from...... confocal imaging stacks. The technique involves projection of volumetric image data onto a triangulated surface mesh representation of the membrane, correction of photoselection effects and global motion of the vesicle during image acquisition and segmentation of the surface into domains using histograms...

Cellular features of psoriatic skin: imaging and quantification using in vivo reflectance confocal microscopy

NARCIS (Netherlands)

Wolberink, E.A.W.; Erp, P.E.J. van; Teussink, M.M.; Kerkhof, P.C.M. van de; Gerritsen, M.J.P.

2011-01-01

BACKGROUND: In vivo reflectance confocal microscopy (RCM) is a novel, exciting imaging technique. It provides images of cell-and tissue structures and dynamics in situ, in real time, without the need for ex vivo tissue samples. RCM visualizes the superficial part of human skin up to a depth of 250

Effective Thermal Inactivation of the Spores of Bacillus cereus Biofilms Using Microwave.

Science.gov (United States)

Park, Hyong Seok; Yang, Jungwoo; Choi, Hee Jung; Kim, Kyoung Heon

2017-07-28

Microwave sterilization was performed to inactivate the spores of biofilms of Bacillus cereus involved in foodborne illness. The sterilization conditions, such as the amount of water and the operating temperature and treatment time, were optimized using statistical analysis based on 15 runs of experimental results designed by the Box-Behnken method. Statistical analysis showed that the optimal conditions for the inactivation of B. cereus biofilms were 14 ml of water, 108°C of temperature, and 15 min of treatment time. Interestingly, response surface plots showed that the amount of water is the most important factor for microwave sterilization under the present conditions. Complete inactivation by microwaves was achieved in 5 min, and the inactivation efficiency by microwave was obviously higher than that by conventional steam autoclave. Finally, confocal laser scanning microscopy images showed that the principal effect of microwave treatment was cell membrane disruption. Thus, this study can contribute to the development of a process to control food-associated pathogens.

Microwave imaging for plasma diagnostics and its applications

International Nuclear Information System (INIS)

Mase, A.; Kogi, Y.; Ito, N.

2007-01-01

Microwave to millimeter-wave diagnostic techniques such as interferometry, reflectometry, scattering, and radiometry have been powerful tools for diagnosing magnetically confined plasmas. Important plasma parameters were measured to clarify the physics issues such as stability, wave phenomena, and fluctuation-induced transport. Recent advances in microwave and millimeter-wave technology together with computer technology have enabled the development of advanced diagnostics for visualization of 2D and 3D structures of plasmas. Microwave/millimeter-wave imaging is expected to be one of the most promising diagnostic methods for this purpose. We report here on the representative microwave diagnostics and their industrial applications as well as application to magnetically-confined plasmas. (author)

In vivo subsurface morphological and functional cellular and subcellular imaging of the gastrointestinal tract with confocal mini-microscopy

Institute of Scientific and Technical Information of China (English)

Martin Goetz; Beena Memadathil; Stefan Biesterfeld; Constantin Schneider; Sebastian Gregor; Peter R Galle; Markus F Neurath; Ralf Kiesslich

2007-01-01

AIM: To evaluate a newly developed hand-held confocal probe for in vivo microscopic imaging of the complete gastrointestinal tract in rodents.METHODS: A novel rigid confocal probe (diameter 7 mm) was designed with optical features similar to the flexible endomicroscopy system for use in humans using a 488 nm single line laser for fluorophore excitation.Light emission was detected at 505 to 750 nm. The field of view was 475 μm × 475 μm. Optical slice thickness was 7 μm with a lateral resolution of 0.7 μm. Subsurface serial images at different depths (surface to 250 μm)were generated in real time at 1024 × 1024 pixels (0.8 frames/s) by placing the probe onto the tissue in gentle,stable contact. Tissue specimens were sampled for histopathological correlation.RESULTS: The esophagus, stomach, small and large intestine and meso, liver, pancreas and gall bladder were visualised in vivo at high resolution in n = 48 mice.Real time microscopic imaging with the confocal minimicroscopy probe was easy to achieve. The different staining protocols (fluorescein, acriflavine, FITC-labelled dextran and L. esculentum lectin) each highlighted specific aspects of the tissue, and in vivo imaging correlated excellently with conventional histology. In vivo blood flow monitoring added a functional quality to morphologic imaging.CONCLUSION: Confocal microscopy is feasible in vivo allowing the visualisation of the complete GI tract at high resolution even of subsurface tissue structures.The new confocal probe design evaluated in this study is compatible with laparoscopy and significantly expands the field of possible applications to intra-abdominal organs. It allows immediate testing of new in vivo staining and application options and therefore permits rapid transfer from animal studies to clinical use in patients.

Combining total internal reflection sum frequency spectroscopy spectral imaging and confocal fluorescence microscopy.

Science.gov (United States)

Allgeyer, Edward S; Sterling, Sarah M; Gunewardene, Mudalige S; Hess, Samuel T; Neivandt, David J; Mason, Michael D

2015-01-27

Understanding surface and interfacial lateral organization in material and biological systems is critical in nearly every field of science. The continued development of tools and techniques viable for elucidation of interfacial and surface information is therefore necessary to address new questions and further current investigations. Sum frequency spectroscopy (SFS) is a label-free, nonlinear optical technique with inherent surface specificity that can yield critical organizational information on interfacial species. Unfortunately, SFS provides no spatial information on a surface; small scale heterogeneities that may exist are averaged over the large areas typically probed. Over the past decade, this has begun to be addressed with the advent of SFS microscopy. Here we detail the construction and function of a total internal reflection (TIR) SFS spectral and confocal fluorescence imaging microscope directly amenable to surface investigations. This instrument combines, for the first time, sample scanning TIR-SFS imaging with confocal fluorescence microscopy.

Evaluation of Yogurt Microstructure Using Confocal Laser Scanning Microscopy and Image Analysis

DEFF Research Database (Denmark)

Skytte, Jacob Lercke; Ghita, Ovidiu; Whelan, Paul F.

2015-01-01

The microstructure of protein networks in yogurts defines important physical properties of the yogurt and hereby partly its quality. Imaging this protein network using confocal scanning laser microscopy (CSLM) has shown good results, and CSLM has become a standard measuring technique for fermented...... to image texture description. Here, CSLM images from a yogurt fermentation study are investigated, where production factors including fat content, protein content, heat treatment, and incubation temperature are varied. The descriptors are evaluated through nearest neighbor classification, variance analysis...... scanning microscopy images can be used to provide information on the protein microstructure in yogurt products. For large numbers of microscopy images, subjective evaluation becomes a difficult or even impossible approach, if the images should be incorporated in any form of statistical analysis alongside...

Near-Infrared Confocal Laser Reflectance Cytoarchitectural Imaging of the Substantia Nigra and Cerebellum in the Fresh Human Cadaver.

Science.gov (United States)

Cheyuo, Cletus; Grand, Walter; Balos, Lucia L

2017-01-01

Cytoarchitectural neuroimaging remains critical for diagnosis of many brain diseases. Fluorescent dye-enhanced, near-infrared confocal in situ cellular imaging of the brain has been reported. However, impermeability of the blood-brain barrier to most fluorescent dyes limits clinical utility of this modality. The differential degree of reflectance from brain tissue with unenhanced near-infrared imaging may represent an alternative technique for in situ cytoarchitectural neuroimaging. We assessed the utility of unenhanced near-infrared confocal laser reflectance imaging of the cytoarchitecture of the cerebellum and substantia nigra in 2 fresh human cadaver brains using a confocal near-infrared laser probe. Cellular images based on near-infrared differential reflectance were captured at depths of 20-180 μm from the brain surface. Parts of the cerebellum and substantia nigra imaged using the probe were subsequently excised and stained with hematoxylin and eosin for histologic correlation. Near-infrared reflectance imaging revealed the 3-layered cytoarchitecture of the cerebellum, with Purkinje cells appearing hyperreflectant. In the substantia nigra, neurons appeared hyporeflectant with hyperreflectant neuromelanin cytoplasmic inclusions. Cytoarchitecture of the cerebellum and substantia nigra revealed on near-infrared imaging closely correlated with the histology on hematoxylin-eosin staining. We showed that unenhanced near-infrared reflectance imaging of fresh human cadaver brain can reliably identify and distinguish neurons and detailed cytoarchitecture of the cerebellum and substantia nigra. Copyright © 2016 Elsevier Inc. All rights reserved.

High resolution 3D confocal microscope imaging of volcanic ash particles.

Science.gov (United States)

Wertheim, David; Gillmore, Gavin; Gill, Ian; Petford, Nick

2017-07-15

We present initial results from a novel high resolution confocal microscopy study of the 3D surface structure of volcanic ash particles from two recent explosive basaltic eruptions, Eyjafjallajökull (2010) and Grimsvötn (2011), in Iceland. The majority of particles imaged are less than 100μm in size and include PM 10 s, known to be harmful to humans if inhaled. Previous studies have mainly used 2D microscopy to examine volcanic particles. The aim of this study was to test the potential of 3D laser scanning confocal microscopy as a reliable analysis tool for these materials and if so to what degree high resolution surface and volume data could be obtained that would further aid in their classification. First results obtained using an Olympus LEXT scanning confocal microscope with a ×50 and ×100 objective lens are highly encouraging. They reveal a range of discrete particle types characterised by sharp or concave edges consistent with explosive formation and sudden rupture of magma. Initial surface area/volume ratios are given that may prove useful in subsequent modelling of damage to aircraft engines and human tissue where inhalation has occurred. Copyright © 2017 Elsevier B.V. All rights reserved.

Imaging rat esophagus using combination of reflectance confocal and multiphoton microscopy

International Nuclear Information System (INIS)

Zhuo, S M; Chen, J X; Jiang, X S; Lu, K C; Xie, S S

2008-01-01

We combine reflectance confocal microscopy (RCM) with multiphoton microscopy (MPM) to image rat esophagus. The two imaging modalities allow detection of layered–resolved complementary information from esophagus. In the keratinizing layer, the keratinocytes boundaries can be characterized by RCM, while the keratinocytes cytoplasm (keratin) can be further imaged by multiphoton autofluorescence signal. In the epithelium, the epithelial cellular boundaries and nucleus can be detected by RCM, and MPM can be used for imaging epithelial cell cytoplasm and monitoring metabolic state of epithelium. In the stroma, multiphoton autofluorescence signal is used to image elastin and second harmonic generation signal is utilized to detect collagen, while RCM is used to determine the optical property of stroma. Overall, these results suggest that the combination of RCM and MPM has potential to provide more important and comprehensive information for early diagnosis of esophageal cancer

Special Sensor Microwave Imager/Sounder (SSMIS) Sensor Data Record (SDR) in netCDF

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Special Sensor Microwave Imager/Sounder (SSMIS) is a series of passive microwave conically scanning imagers and sounders onboard the DMSP satellites beginning...

Special Sensor Microwave Imager/Sounder (SSMIS) Temperature Data Record (TDR) in netCDF

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Special Sensor Microwave Imager/Sounder (SSMIS) is a series of passive microwave conically scanning imagers and sounders onboard the DMSP satellites beginning...

Sub-Airy Confocal Adaptive Optics Scanning Ophthalmoscopy.

Science.gov (United States)

Sredar, Nripun; Fagbemi, Oladipo E; Dubra, Alfredo

2018-04-01

To demonstrate the viability of improving transverse image resolution in reflectance scanning adaptive optics ophthalmoscopy using sub-Airy disk confocal detection. The foveal cone mosaic was imaged in five human subjects free of known eye disease using two custom adaptive optics scanning light ophthalmoscopes (AOSLOs) in reflectance with 7.75 and 4.30 mm pupil diameters. Confocal pinholes of 0.5, 0.6, 0.8, and 1.0 Airy disk diameters (ADDs) were used in a retinal conjugate plane before the light detector. Average cone photoreceptor intensity profile width and power spectrum were calculated for the resulting images. Detected energy using a model eye was recorded for each pinhole size. The cone photoreceptor mosaic is better resolved with decreasing confocal pinhole size, with the high spatial frequency content of the images enhanced in both the large- and small-pupil AOSLOs. The average cone intensity profile width was reduced by ∼15% with the use of a 0.5 ADD pinhole when compared to a 1.0 ADD, with an accompanying reduction in signal greater than a factor of four. The use of sub-Airy disk confocal pinhole detection without increasing retinal light exposure results in a substantial improvement in image resolution at the cost of larger than predicted signal reduction. Improvement in transverse resolution using sub-Airy disk confocal detection is a practical and low-cost approach that is applicable to all point- and line-scanning ophthalmoscopes, including optical coherence tomographers.

Automatic segmentation of cell nuclei from confocal laser scanning microscopy images

International Nuclear Information System (INIS)

Kelemen, A.; Reist, H.W.

1997-01-01

A newly developed experimental method combines the possibility of irradiating more than a thousand cells simultaneous with an efficient colony-forming ability and with the capability of localizing a particle track through a cell nucleus together with the assessment of the energy transfer by digital superposition of the image containing the track with that of the cells. To assess the amount of energy deposition by particles traversing the cell nucleus the intersection lengths of the particle tracks have to be known. Intersection lengths can be obtained by determining the 3D surface contours of the irradiated cell nuclei. Confocal laser scanning microscopy using specific DNA fluorescent dye offers a possible way for the determination of the 3D shape of individual nuclei. Unfortunately, such experiments cannot be performed on living cells. One solution to this problem can be provided by building a statistical model of the shape of the nuclei of the exposed cells. In order to build such a statistical model, a large number of cell nuclei have to be identified and segmented from confocal laser scanning microscopy images. The present paper describes a method to perform this 3D segmentation in an automatic manner in order to create a solid basis for the statistical model. (author) 2 figs., 4 refs

Handheld microwave bomb-detecting imaging system

Science.gov (United States)

Gorwara, Ashok; Molchanov, Pavlo

2017-05-01

Proposed novel imaging technique will provide all weather high-resolution imaging and recognition capability for RF/Microwave signals with good penetration through highly scattered media: fog, snow, dust, smoke, even foliage, camouflage, walls and ground. Image resolution in proposed imaging system is not limited by diffraction and will be determined by processor and sampling frequency. Proposed imaging system can simultaneously cover wide field of view, detect multiple targets and can be multi-frequency, multi-function. Directional antennas in imaging system can be close positioned and installed in cell phone size handheld device, on small aircraft or distributed around protected border or object. Non-scanning monopulse system allows dramatically decrease in transmitting power and at the same time provides increased imaging range by integrating 2-3 orders more signals than regular scanning imaging systems.

Development of local oscillator integrated antenna array for microwave imaging diagnostics

International Nuclear Information System (INIS)

Kuwahara, D.; Shinohara, S.; Ito, N.; Nagayama, Y.; Tsuchiya, H.; Yoshikawa, M.; Kohagura, J.; Yoshinaga, T.; Yamaguchi, S.; Kogi, Y.; Mase, A.

2015-01-01

Microwave imaging diagnostics are powerful tools that are used to obtain details of complex structures and behaviors of such systems as magnetically confined plasmas. For example, microwave imaging reflectometry and microwave imaging interferometers are suitable for observing phenomena that are involved with electron density fluctuations; moreover, electron cyclotron emission imaging diagnostics enable us to accomplish the significant task of observing MHD instabilities in large tokamaks. However, microwave imaging systems include difficulties in terms of multi-channelization and cost. Recently, we solved these problems by developing a Horn-antenna Mixer Array (HMA), a 50 - 110 GHz 1-D heterodyne- type antenna array, which can be easily stacked as a 2-D receiving array, because it uses an end-fire element. However, the HMA still evidenced problems owing to the requirement for local oscillation (LO) optics and an expensive high-power LO source. To solve this problem, we have developed an upgraded HMA, named the Local Integrated Antenna array (LIA), in which each channel has an internal LO supply using a frequency multiplier integrated circuit. Therefore, the proposed antenna array eliminates the need for both the LO optics and the high-power LO source. This paper describes the principle of the LIA, and provides details about an 8 channel prototype LIA

Development of anatomically and dielectrically accurate breast phantoms for microwave imaging applications

Science.gov (United States)

O'Halloran, M.; Lohfeld, S.; Ruvio, G.; Browne, J.; Krewer, F.; Ribeiro, C. O.; Inacio Pita, V. C.; Conceicao, R. C.; Jones, E.; Glavin, M.

2014-05-01

Breast cancer is one of the most common cancers in women. In the United States alone, it accounts for 31% of new cancer cases, and is second only to lung cancer as the leading cause of deaths in American women. More than 184,000 new cases of breast cancer are diagnosed each year resulting in approximately 41,000 deaths. Early detection and intervention is one of the most significant factors in improving the survival rates and quality of life experienced by breast cancer sufferers, since this is the time when treatment is most effective. One of the most promising breast imaging modalities is microwave imaging. The physical basis of active microwave imaging is the dielectric contrast between normal and malignant breast tissue that exists at microwave frequencies. The dielectric contrast is mainly due to the increased water content present in the cancerous tissue. Microwave imaging is non-ionizing, does not require breast compression, is less invasive than X-ray mammography, and is potentially low cost. While several prototype microwave breast imaging systems are currently in various stages of development, the design and fabrication of anatomically and dielectrically representative breast phantoms to evaluate these systems is often problematic. While some existing phantoms are composed of dielectrically representative materials, they rarely accurately represent the shape and size of a typical breast. Conversely, several phantoms have been developed to accurately model the shape of the human breast, but have inappropriate dielectric properties. This study will brie y review existing phantoms before describing the development of a more accurate and practical breast phantom for the evaluation of microwave breast imaging systems.

Development of a High-Throughput Microwave Imaging System for Concealed Weapons Detection

Science.gov (United States)

2016-07-15

hardware. Index Terms—Microwave imaging, multistatic radar, Fast Fourier Transform (FFT). I. INTRODUCTION Near-field microwave imaging is a non- ionizing ...real-time microwave camera at 24 ghz,” IEEE Transactions on Antennas and Propagation , vol. 60, no. 2, pp. 1114– 1125, 2012. [2] E. C. Fear, X. Li, S. C...on Biomedical Engineering, vol. 49, no. 8, pp. 812–822, 2002. [3] D. M. Sheen, D. L. McMakin, and T. E. Hall, “Three-dimensional millimeter- wave

Confocal Raman microscopy

CERN Document Server

Dieing, Thomas; Hollricher, Olaf

2018-01-01

This second edition provides a cutting-edge overview of physical, technical and scientific aspects related to the widely used analytical method of confocal Raman microscopy. The book includes expanded background information and adds insights into how confocal Raman microscopy, especially 3D Raman imaging, can be integrated with other methods to produce a variety of correlative microscopy combinations. The benefits are then demonstrated and supported by numerous examples from the fields of materials science, 2D materials, the life sciences, pharmaceutical research and development, as well as the geosciences.

Confocal Raman Microscopy

CERN Document Server

Dieing, Thomas; Toporski, Jan

2011-01-01

Confocal Raman Microscopy is a relatively new technique that allows chemical imaging without specific sample preparation. By integrating a sensitive Raman spectrometer within a state-of-the-art microscope, Raman microscopy with a spatial resolution down to 200nm laterally and 500nm vertically can be achieved using visible light excitation. Recent developments in detector and computer technology as well as optimized instrument design have reduced integration times of Raman spectra by orders of magnitude, so that complete images consisting of tens of thousands of Raman spectra can be acquired in seconds or minutes rather than hours, which used to be standard just one decade ago. The purpose of this book is to provide the reader a comprehensive overview of the rapidly developing field of Confocal Raman Microscopy and its applications.

Visualization and quantitation of abundant macroautophagy in virus-infected cells by confocal three-dimensional fluorescence imaging.

Science.gov (United States)

Jackson, Wallen; Yamada, Masaki; Moninger, Thomas; Grose, Charles

2013-10-01

Varicella-zoster virus (VZV) is a human herpesvirus. Primary infection causes varicella (chickenpox), a viremic illness typified by an exanthem consisting of several hundred vesicles. When VZV reactivates from latency in the spinal ganglia during late adulthood, the emerging virus causes a vesicular dermatomal rash (herpes zoster or shingles). To expand investigations of autophagy during varicella and zoster, newer 3D imaging technology was combined with laser scanning confocal microscopy to provide animations of autophagosomes in the vesicular rash. First, the cells were immunolabeled with antibodies against VZV proteins and the LC3 protein, an integral autophagosomal protein. Antibody reagents lacking activity against the human blood group A1 antigen were selected. After laser excitation of the samples, optimized emission detection bandwidths were configured by Zeiss Zen control software. Confocal Z-stacks comprising up to 40 optical slices were reconstructed into 3D animations with the aid of Imaris software. With this imaging technology, individual autophagosomes were clearly detectable as spheres within each vesicular cell. To enumerate the number of autophagosomes, data sets from 50 cells were reconstructed as 3D fluorescence images and analyzed with MeasurementPro software. The mean number of autophagosomes per infected vesicular cell was >100, although over 200 autophagosomes were seen in a few cells. In summary, macroautophagy was easily quantitated within VZV-infected cells after immunolabeling and imaging by 3D confocal animation technology. These same 3D imaging techniques will be applicable for investigations of autophagy in other virus-infected cells. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

Fused oblique incidence reflectometry and confocal fluorescence microscopy

Science.gov (United States)

Risi, Matthew D.; Rouse, Andrew R.; Gmitro, Arthur F.

2011-03-01

Confocal microendoscopy provides real-time high resolution cellular level images via a minimally invasive procedure, but relies on exogenous fluorophores, has a relatively limited penetration depth (100 μm) and field of view (700 μm), and produces a high rate of detailed information to the user. A new catheter based multi-modal system has been designed that combines confocal imaging and oblique incidence reflectometry (OIR), which is a non-invasive method capable of rapidly extracting tissue absorption, μa, and reduced scattering, μ's, spectra from tissue. The system builds on previous developments of a custom slit-scan multi-spectral confocal microendoscope and is designed to rapidly switch between diffuse spectroscopy and confocal fluorescence imaging modes of operation. An experimental proof-of-principle catheter has been developed that consists of a fiber bundle for traditional confocal fluorescence imaging and a single OIR source fiber which is manually redirected at +/- 26 degrees. Diffusely scattered light from each orientation of the source fiber is collected via the fiber bundle, with a frame of data representing spectra collected at a range of distances from the OIR source point. Initial results with intralipid phantoms show good agreement to published data over the 550-650 nm spectral range. We successfully imaged and measured the optical properties of rodent cardiac muscle.

Heterogeneous Breast Phantom Development for Microwave Imaging Using Regression Models

Directory of Open Access Journals (Sweden)

Camerin Hahn

2012-01-01

Full Text Available As new algorithms for microwave imaging emerge, it is important to have standard accurate benchmarking tests. Currently, most researchers use homogeneous phantoms for testing new algorithms. These simple structures lack the heterogeneity of the dielectric properties of human tissue and are inadequate for testing these algorithms for medical imaging. To adequately test breast microwave imaging algorithms, the phantom has to resemble different breast tissues physically and in terms of dielectric properties. We propose a systematic approach in designing phantoms that not only have dielectric properties close to breast tissues but also can be easily shaped to realistic physical models. The approach is based on regression model to match phantom's dielectric properties with the breast tissue dielectric properties found in Lazebnik et al. (2007. However, the methodology proposed here can be used to create phantoms for any tissue type as long as ex vivo, in vitro, or in vivo tissue dielectric properties are measured and available. Therefore, using this method, accurate benchmarking phantoms for testing emerging microwave imaging algorithms can be developed.

High Definition Confocal Imaging Modalities for the Characterization of Tissue-Engineered Substitutes.

Science.gov (United States)

Mayrand, Dominique; Fradette, Julie

2018-01-01

Optimal imaging methods are necessary in order to perform a detailed characterization of thick tissue samples from either native or engineered tissues. Tissue-engineered substitutes are featuring increasing complexity including multiple cell types and capillary-like networks. Therefore, technical approaches allowing the visualization of the inner structural organization and cellular composition of tissues are needed. This chapter describes an optical clearing technique which facilitates the detailed characterization of whole-mount samples from skin and adipose tissues (ex vivo tissues and in vitro tissue-engineered substitutes) when combined with spectral confocal microscopy and quantitative analysis on image renderings.

AMISS - Active and passive MIcrowaves for Security and Subsurface imaging

Science.gov (United States)

Soldovieri, Francesco; Slob, Evert; Turk, Ahmet Serdar; Crocco, Lorenzo; Catapano, Ilaria; Di Matteo, Francesca

2013-04-01

The FP7-IRSES project AMISS - Active and passive MIcrowaves for Security and Subsurface imaging is based on a well-combined network among research institutions of EU, Associate and Third Countries (National Research Council of Italy - Italy, Technische Universiteit Delft - The Netherlands, Yildiz Technical University - Turkey, Bauman Moscow State Technical University - Russia, Usikov Institute for Radio-physics and Electronics and State Research Centre of Superconductive Radioelectronics "Iceberg" - Ukraine and University of Sao Paulo - Brazil) with the aims of achieving scientific advances in the framework of microwave and millimeter imaging systems and techniques for security and safety social issues. In particular, the involved partners are leaders in the scientific areas of passive and active imaging and are sharing their complementary knowledge to address two main research lines. The first one regards the design, characterization and performance evaluation of new passive and active microwave devices, sensors and measurement set-ups able to mitigate clutter and increase information content. The second line faces the requirements to make State-of-the-Art processing tools compliant with the instrumentations developed in the first line, suitable to work in electromagnetically complex scenarios and able to exploit the unexplored possibilities offered by new instrumentations. The main goals of the project are: 1) Development/improvement and characterization of new sensors and systems for active and passive microwave imaging; 2) Set up, analysis and validation of state of art/novel data processing approach for GPR in critical infrastructure and subsurface imaging; 3) Integration of state of art and novel imaging hardware and characterization approaches to tackle realistic situations in security, safety and subsurface prospecting applications; 4) Development and feasibility study of bio-radar technology (system and data processing) for vital signs detection and

Parameter Search Algorithms for Microwave Radar-Based Breast Imaging: Focal Quality Metrics as Fitness Functions.

Science.gov (United States)

O'Loughlin, Declan; Oliveira, Bárbara L; Elahi, Muhammad Adnan; Glavin, Martin; Jones, Edward; Popović, Milica; O'Halloran, Martin

2017-12-06

Inaccurate estimation of average dielectric properties can have a tangible impact on microwave radar-based breast images. Despite this, recent patient imaging studies have used a fixed estimate although this is known to vary from patient to patient. Parameter search algorithms are a promising technique for estimating the average dielectric properties from the reconstructed microwave images themselves without additional hardware. In this work, qualities of accurately reconstructed images are identified from point spread functions. As the qualities of accurately reconstructed microwave images are similar to the qualities of focused microscopic and photographic images, this work proposes the use of focal quality metrics for average dielectric property estimation. The robustness of the parameter search is evaluated using experimental dielectrically heterogeneous phantoms on the three-dimensional volumetric image. Based on a very broad initial estimate of the average dielectric properties, this paper shows how these metrics can be used as suitable fitness functions in parameter search algorithms to reconstruct clear and focused microwave radar images.

A portable confocal hyperspectral microscope without any scan or tube lens and its application in fluorescence and Raman spectral imaging

Science.gov (United States)

Li, Jingwei; Cai, Fuhong; Dong, Yongjiang; Zhu, Zhenfeng; Sun, Xianhe; Zhang, Hequn; He, Sailing

2017-06-01

In this study, a portable confocal hyperspectral microscope is developed. In traditional confocal laser scanning microscopes, scan lens and tube lens are utilized to achieve a conjugate relationship between the galvanometer and the back focal plane of the objective, in order to achieve a better resolution. However, these lenses make it difficult to scale down the volume of the system. In our portable confocal hyperspectral microscope (PCHM), the objective is placed directly next to the galvomirror. Thus, scan lens and tube lens are not included in our system and the size of this system is greatly reduced. Furthermore, the resolution is also acceptable in many biomedical and food-safety applications. Through reducing the optical length of the system, the signal detection efficiency is enhanced. This is conducive to realizing both the fluorescence and Raman hyperspectral imaging. With a multimode fiber as a pinhole, an improved image contrast is also achieved. Fluorescent spectral images for HeLa cells/fingers and Raman spectral images of kumquat pericarp are present. The spectral resolution and spatial resolutions are about 0.4 nm and 2.19 μm, respectively. These results demonstrate that this portable hyperspectral microscope can be used in in-vivo fluorescence imaging and in situ Raman spectral imaging.

FluoRender: An application of 2D image space methods for 3D and 4D confocal microscopy data visualization in neurobiology research

KAUST Repository

Wan, Yong; Otsuna, Hideo; Chien, Chi-Bin; Hansen, Charles

2012-01-01

2D image space methods are processing methods applied after the volumetric data are projected and rendered into the 2D image space, such as 2D filtering, tone mapping and compositing. In the application domain of volume visualization, most 2D image space methods can be carried out more efficiently than their 3D counterparts. Most importantly, 2D image space methods can be used to enhance volume visualization quality when applied together with volume rendering methods. In this paper, we present and discuss the applications of a series of 2D image space methods as enhancements to confocal microscopy visualizations, including 2D tone mapping, 2D compositing, and 2D color mapping. These methods are easily integrated with our existing confocal visualization tool, FluoRender, and the outcome is a full-featured visualization system that meets neurobiologists' demands for qualitative analysis of confocal microscopy data. © 2012 IEEE.

FluoRender: An application of 2D image space methods for 3D and 4D confocal microscopy data visualization in neurobiology research

KAUST Repository

Wan, Yong

2012-02-01

2D image space methods are processing methods applied after the volumetric data are projected and rendered into the 2D image space, such as 2D filtering, tone mapping and compositing. In the application domain of volume visualization, most 2D image space methods can be carried out more efficiently than their 3D counterparts. Most importantly, 2D image space methods can be used to enhance volume visualization quality when applied together with volume rendering methods. In this paper, we present and discuss the applications of a series of 2D image space methods as enhancements to confocal microscopy visualizations, including 2D tone mapping, 2D compositing, and 2D color mapping. These methods are easily integrated with our existing confocal visualization tool, FluoRender, and the outcome is a full-featured visualization system that meets neurobiologists\\' demands for qualitative analysis of confocal microscopy data. © 2012 IEEE.

Double-Stage Delay Multiply and Sum Beamforming Algorithm: Application to Linear-Array Photoacoustic Imaging

OpenAIRE

Mozaffarzadeh, Moein; Mahloojifar, Ali; Orooji, Mahdi; Adabi, Saba; Nasiriavanaki, Mohammadreza

2018-01-01

Photoacoustic imaging (PAI) is an emerging medical imaging modality capable of providing high spatial resolution of Ultrasound (US) imaging and high contrast of optical imaging. Delay-and-Sum (DAS) is the most common beamforming algorithm in PAI. However, using DAS beamformer leads to low resolution images and considerable contribution of off-axis signals. A new paradigm namely Delay-Multiply-and-Sum (DMAS), which was originally used as a reconstruction algorithm in confocal microwave imaging...

Speckle-illuminated fluorescence confocal microscopy, using a digital micro-mirror device

International Nuclear Information System (INIS)

Jiang, Shi-Hong; Walker, John G

2009-01-01

An implementation of a speckle-illuminated fluorescence confocal microscope using a digital micro-mirror device (DMD) is described. The DMD not only projects a sequence of imaged binary speckle patterns onto the specimen at a very high frame rate but also operates as a spatial light modulator to perform real-time optical data processing. Frame averaging is accomplished by CCD charge accumulation during a single exposure. The recorded time-averaged image is a confocal image plus an unwanted non-confocal image which can be removed by recording a separate image. Experimental results with image acquisition within a fraction of a second are shown. Images of a thin biological sample are also shown to demonstrate practical application of the technique

Confocal microscopy and imaging profilometry: A new tool aimed to evaluate aesthetic procedures.

Science.gov (United States)

Fabbrocini, Gabriella; Mazzella, Caterina; Montagnaro, Fabio; De Padova, Maria Pia; Lorenzi, Sandra; Tedeschi, Aurora; Forgione, Patrizia; Capasso, Claudia; Sivero, Luigi; Velotti, Carla; Russo, Daniela; Vitiello, Rosa; Ilardi, Gennaro

2017-02-01

According to the American Academy of Aesthetic Plastic Surgeons, more than 11 million cosmetic surgical and nonsurgical procedures were performed by board-certified plastic surgeons, dermatologists and otolaryngologists in the United States, totaling more than 12 billion dollars. We performed a retrospective observational multi-centric study on patients treated with a non-animal origin cross-linked hyaluronic acid with different molecular weights for nasolabial folds, evaluating through a new imaging system, profilometric techniques with the confocal microscopy, the durability, the efficacy and the safety of this product. From 25 patients, 150 silicone casts were obtained: 75 casts of the right nasolabial fold and 75 casts of the left nasolabial fold. Roughness arithmetical average of the right fold at T2 decreased by 50% versus T0 and by 40% compared to T1; at T2, it decreased by the 45% versus T0 and by 35% compared to T1. No side effects were reported. Results proved that the analysis of the skin microreliefs through confocal microscopy is a new imaging system that allows to evaluate with precision and safety the results of aesthetic treatments such as fillers objectively.

Resolution doubling in fluorescence microscopy with confocal spinning-disk image scanning microscopy.

Science.gov (United States)

Schulz, Olaf; Pieper, Christoph; Clever, Michaela; Pfaff, Janine; Ruhlandt, Aike; Kehlenbach, Ralph H; Wouters, Fred S; Großhans, Jörg; Bunt, Gertrude; Enderlein, Jörg

2013-12-24

We demonstrate how a conventional confocal spinning-disk (CSD) microscope can be converted into a doubly resolving image scanning microscopy (ISM) system without changing any part of its optical or mechanical elements. Making use of the intrinsic properties of a CSD microscope, we illuminate stroboscopically, generating an array of excitation foci that are moved across the sample by varying the phase between stroboscopic excitation and rotation of the spinning disk. ISM then generates an image with nearly doubled resolution. Using conventional fluorophores, we have imaged single nuclear pore complexes in the nuclear membrane and aggregates of GFP-conjugated Tau protein in three dimensions. Multicolor ISM was shown on cytoskeletal-associated structural proteins and on 3D four-color images including MitoTracker and Hoechst staining. The simple adaptation of conventional CSD equipment allows superresolution investigations of a broad variety of cell biological questions.

Methods of Hematoxylin and Erosin Image Information Acquisition and Optimization in Confocal Microscopy.

Science.gov (United States)

Yoon, Woong Bae; Kim, Hyunjin; Kim, Kwang Gi; Choi, Yongdoo; Chang, Hee Jin; Sohn, Dae Kyung

2016-07-01

We produced hematoxylin and eosin (H&E) staining-like color images by using confocal laser scanning microscopy (CLSM), which can obtain the same or more information in comparison to conventional tissue staining. We improved images by using several image converting techniques, including morphological methods, color space conversion methods, and segmentation methods. An image obtained after image processing showed coloring very similar to that in images produced by H&E staining, and it is advantageous to conduct analysis through fluorescent dye imaging and microscopy rather than analysis based on single microscopic imaging. The colors used in CLSM are different from those seen in H&E staining, which is the method most widely used for pathologic diagnosis and is familiar to pathologists. Computer technology can facilitate the conversion of images by CLSM to be very similar to H&E staining images. We believe that the technique used in this study has great potential for application in clinical tissue analysis.

Confocal filtering in cathodoluminescence microscopy of nanostructures

Science.gov (United States)

Narváez, Angela C.; Weppelman, I. Gerward C.; Moerland, Robert J.; Hoogenboom, Jacob P.; Kruit, Pieter

2014-06-01

Cathodoluminescence (CL) microscopy allows optical characterization of nanostructures at high spatial resolution. At the nanoscale, a main challenge of the technique is related to the background CL generated within the sample substrate. Here, we implement confocal detection of the CL signal to minimize the background contribution to the measurement. Nano-phosphors were used as point sources to evaluate the filtering capabilities of our confocal CL system, obtaining an axial intensity profile with 2.7 μm full width at half maximum for the central peak, in good correspondence with theoretical expectations. Considering the electron interaction volume, we found that the confocal filter becomes effective for electron energies above 20 keV, when using a 25 μm pinhole (0.86 Airy units). To illustrate our approach, we present confocal CL imaging of gold nanowires and triangular shaped plates deposited on an indium-tin oxide covered glass substrate, comparing the images with those obtained in standard unfiltered CL detection. The results show that confocal CL microscopy is a valuable tool for the investigation of nanostructures on highly cathodoluminescent substrates, widely used in biological and optical applications.

Confocal filtering in cathodoluminescence microscopy of nanostructures

Energy Technology Data Exchange (ETDEWEB)

Narváez, Angela C., E-mail: a.c.narvaez@tudelft.nl, E-mail: j.p.hoogenboom@tudelft.nl; Weppelman, I. Gerward C.; Moerland, Robert J.; Hoogenboom, Jacob P., E-mail: a.c.narvaez@tudelft.nl, E-mail: j.p.hoogenboom@tudelft.nl; Kruit, Pieter [Imaging Physics, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628CJ Delft (Netherlands)

2014-06-23

Cathodoluminescence (CL) microscopy allows optical characterization of nanostructures at high spatial resolution. At the nanoscale, a main challenge of the technique is related to the background CL generated within the sample substrate. Here, we implement confocal detection of the CL signal to minimize the background contribution to the measurement. Nano-phosphors were used as point sources to evaluate the filtering capabilities of our confocal CL system, obtaining an axial intensity profile with 2.7 μm full width at half maximum for the central peak, in good correspondence with theoretical expectations. Considering the electron interaction volume, we found that the confocal filter becomes effective for electron energies above 20 keV, when using a 25 μm pinhole (0.86 Airy units). To illustrate our approach, we present confocal CL imaging of gold nanowires and triangular shaped plates deposited on an indium-tin oxide covered glass substrate, comparing the images with those obtained in standard unfiltered CL detection. The results show that confocal CL microscopy is a valuable tool for the investigation of nanostructures on highly cathodoluminescent substrates, widely used in biological and optical applications.

Enhancement of fluorescence confocal scanning microscopy lateral resolution by use of structured illumination

International Nuclear Information System (INIS)

Kim, Taejoong; Gweon, DaeGab; Lee, Jun-Hee

2009-01-01

Confocal microscopy is an optical imaging technique used to reconstruct three-dimensional images without physical sectioning. As with other optical microscopes, the lateral resolution of the confocal microscope cannot surpass the diffraction limit. This paper presents a novel imaging system, structured illumination confocal scanning microscopy (SICSM), that uses structured illumination to improve the lateral resolution of the confocal microscope. The SICSM can easily be implemented by introducing a structured illumination generating optics to conventional line-scanning fluorescence confocal microscopy. In this paper, we report our analysis of the lateral and axial resolutions of the SICSM by use of mathematical imaging theory. Numerical simulation results show that the lateral resolution of the SICSM is 1.43-fold better than that of the confocal microscope. In the axial direction, however, the resolution of the SICSM is ∼15% poorer than that of the confocal microscope. This deterioration arises because of a decrease in the axial cut-off frequency caused by the process of generating structured illumination. We propose the use of imaging conditions under which a compromise between the axial and lateral resolutions is chosen. Finally, we show simulated images of diversely shaped test objects to demonstrate the lateral and axial resolution performance of the SICSM

Microwave Imaging Reflectometer for TEXTOR

International Nuclear Information System (INIS)

T. Munsat; E. Mazzucato; H. Park; B.H. Deng; C.W. Domier; N.C. Luhmann, Jr.; J. Wang; Z.G. Xia; A.J.H. Donne; and M. van de Pol

2002-01-01

Understanding the behavior of fluctuations in magnetically confined plasmas is essential to the advancement of turbulence-based transport physics. Though microwave reflectometry has proven to be an extremely useful and sensitive tool for measuring small density fluctuations in some circumstances, this technique has been shown to have limited viability for large amplitude, high kq fluctuations and/or core measurements. To this end, a new instrument based on 2-D imaging reflectometry has been developed to measure density fluctuations over an extended plasma region in the TEXTOR tokamak. This technique is made possible by collecting an extended spectrum of reflected waves with large-aperture imaging optics. Details of the imaging reflectometry concept, as well as technical details of the TEXTOR instrument will be presented. Data from roof-of-principle experiments on TEXTOR using a prototype system is presented, as well as results from a systematic off-line study of the advantages and limitations of the imaging reflectometer

A Fast Forward Electromagnetic Solver for Microwave Imaging

DEFF Research Database (Denmark)

Chaber, Bartosz; Mohr, Johan Jacob

2015-01-01

This paper describes an efficient model of an antenna system for microwave imaging. The authors present techniques employed in the process of preparation of this model, as well as an accuracy comparison with the working prototype system....

Development of horn antenna mixer array with internal local oscillator module for microwave imaging diagnostics

Energy Technology Data Exchange (ETDEWEB)

Kuwahara, D., E-mail: dkuwahar@cc.tuat.ac.jp [Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588 (Japan); Ito, N. [Department of Intelligent System Engineering, Ube National College of Technology, Ube, Yamaguchi 755-8555 (Japan); Nagayama, Y. [Department of Helical Plasma Research, National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Yoshinaga, T. [Department of Applied Physics, National Defense Academy, Yokosuka, Kanagawa 239-0811 (Japan); Yamaguchi, S. [Department of Pure and Applied Physics, Kansai University, Suita, Osaka 564-8680 (Japan); Yoshikawa, M.; Kohagura, J. [Graduate School of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Sugito, S. [Equipment Development Center, Institute for Molecular Science, Okazaki, Aichi 444-8585 (Japan); Kogi, Y. [Department of Information Electronics, Fukuoka Institute of Technology, Fukuoka, Fukuoka 811-0295 (Japan); Mase, A. [Art, Science and Technology Center for Cooperative Research, Kyusyu University, Kasuga, Fukuoka 816-8580 (Japan)

2014-11-15

A new antenna array is proposed in order to improve the sensitivity and complexity of microwave imaging diagnostics systems such as a microwave imaging reflectometry, a microwave imaging interferometer, and an electron cyclotron emission imaging. The antenna array consists of five elements: a horn antenna, a waveguide-to-microstrip line transition, a mixer, a local oscillation (LO) module, and an intermediate frequency amplifier. By using an LO module, the LO optics can be removed, and the supplied LO power to each element can be equalized. We report details of the antenna array and characteristics of a prototype antenna array.

Fibered confocal fluorescence microscopy for imaging apoptotic DNA fragmentation at the single-cell level in vivo

International Nuclear Information System (INIS)

Al-Gubory, Kais H.

2005-01-01

The major characteristic of cell death by apoptosis is the loss of nuclear DNA integrity by endonucleases, resulting in the formation of small DNA fragments. The application of confocal imaging to in vivo monitoring of dynamic cellular events, like apoptosis, within internal organs and tissues has been limited by the accessibility to these sites. Therefore, the aim of the present study was to test the feasibility of fibered confocal fluorescence microscopy (FCFM) to image in situ apoptotic DNA fragmentation in surgically exteriorized sheep corpus luteum in the living animal. Following intra-luteal administration of a fluorescent DNA-staining dye, YO-PRO-1, DNA cleavage within nuclei of apoptotic cells was serially imaged at the single-cell level by FCFM. This imaging technology is sufficiently simple and rapid to allow time series in situ detection and visualization of cells undergoing apoptosis in the intact animal. Combined with endoscope, this approach can be used for minimally invasive detection of fluorescent signals and visualization of cellular events within internal organs and tissues and thereby provides the opportunity to study biological processes in the natural physiological environment of the cell in living animals

Bright-field scanning confocal electron microscopy using a double aberration-corrected transmission electron microscope

Energy Technology Data Exchange (ETDEWEB)

Wang, Peng; Behan, Gavin; Kirkland, Angus I. [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Nellist, Peter D., E-mail: peter.nellist@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Cosgriff, Eireann C.; D' Alfonso, Adrian J.; Morgan, Andrew J.; Allen, Leslie J. [School of Physics, University of Melbourne, Parkville, Victoria 3010 (Australia); Hashimoto, Ayako [Advanced Nano-characterization Center, National Institute for Materials Science (NIMS), 3-13 Sakura, Tsukuba 305-0003 (Japan); Takeguchi, Masaki [Advanced Nano-characterization Center, National Institute for Materials Science (NIMS), 3-13 Sakura, Tsukuba 305-0003 (Japan); High Voltage Electron Microscopy Station, NIMS, 3-13 Sakura, Tsukuba 305-0003 (Japan); Mitsuishi, Kazutaka [Advanced Nano-characterization Center, National Institute for Materials Science (NIMS), 3-13 Sakura, Tsukuba 305-0003 (Japan); Quantum Dot Research Center, NIMS, 3-13 Sakura, Tsukuba 305-0003 (Japan); Shimojo, Masayuki [High Voltage Electron Microscopy Station, NIMS, 3-13 Sakura, Tsukuba 305-0003 (Japan); Advanced Science Research Laboratory, Saitama Institute of Technology, 1690 Fusaiji, Fukaya 369-0293 (Japan)

2011-06-15

Scanning confocal electron microscopy (SCEM) offers a mechanism for three-dimensional imaging of materials, which makes use of the reduced depth of field in an aberration-corrected transmission electron microscope. The simplest configuration of SCEM is the bright-field mode. In this paper we present experimental data and simulations showing the form of bright-field SCEM images. We show that the depth dependence of the three-dimensional image can be explained in terms of two-dimensional images formed in the detector plane. For a crystalline sample, this so-called probe image is shown to be similar to a conventional diffraction pattern. Experimental results and simulations show how the diffracted probes in this image are elongated in thicker crystals and the use of this elongation to estimate sample thickness is explored. -- Research Highlights: {yields} The confocal probe image in a scanning confocal electron microscopy image reveals information about the thickness and height of the crystalline layer. {yields} The form of the contrast in a three-dimensional bright-field scanning confocal electron microscopy image can be explained in terms of the confocal probe image. {yields} Despite the complicated form of the contrast in bright-field scanning confocal electron microscopy, we see that depth information is transferred on a 10 nm scale.

Adaptive and robust statistical methods for processing near-field scanning microwave microscopy images.

Science.gov (United States)

Coakley, K J; Imtiaz, A; Wallis, T M; Weber, J C; Berweger, S; Kabos, P

2015-03-01

Near-field scanning microwave microscopy offers great potential to facilitate characterization, development and modeling of materials. By acquiring microwave images at multiple frequencies and amplitudes (along with the other modalities) one can study material and device physics at different lateral and depth scales. Images are typically noisy and contaminated by artifacts that can vary from scan line to scan line and planar-like trends due to sample tilt errors. Here, we level images based on an estimate of a smooth 2-d trend determined with a robust implementation of a local regression method. In this robust approach, features and outliers which are not due to the trend are automatically downweighted. We denoise images with the Adaptive Weights Smoothing method. This method smooths out additive noise while preserving edge-like features in images. We demonstrate the feasibility of our methods on topography images and microwave |S11| images. For one challenging test case, we demonstrate that our method outperforms alternative methods from the scanning probe microscopy data analysis software package Gwyddion. Our methods should be useful for massive image data sets where manual selection of landmarks or image subsets by a user is impractical. Published by Elsevier B.V.

On the performance of SART and ART algorithms for microwave imaging

Science.gov (United States)

Aprilliyani, Ria; Prabowo, Rian Gilang; Basari

2018-02-01

The development of advanced technology leads to the change of human lifestyle in current society. One of the disadvantage impact is arising the degenerative diseases such as cancers and tumors, not just common infectious diseases. Every year, victims of cancers and tumors grow significantly leading to one of the death causes in the world. In early stage, cancer/tumor does not have definite symptoms, but it will grow abnormally as tissue cells and damage normal tissue. Hence, early cancer detection is required. Some common diagnostics modalities such as MRI, CT and PET are quite difficult to be operated in home or mobile environment such as ambulance. Those modalities are also high cost, unpleasant, complex, less safety and harder to move. Hence, this paper proposes a microwave imaging system due to its portability and low cost. In current study, we address on the performance of simultaneous algebraic reconstruction technique (SART) algorithm that was applied in microwave imaging. In addition, SART algorithm performance compared with our previous work on algebraic reconstruction technique (ART), in order to have performance comparison, especially in the case of reconstructed image quality. The result showed that by applying SART algorithm on microwave imaging, suspicious cancer/tumor can be detected with better image quality.

Measurement of capillary lenght from 3D images acquired by confocal microscopy using image analysis and stereology

Czech Academy of Sciences Publication Activity Database

Kubínová, Lucie; Janáček, Jiří; Eržen, I.; Mao, X. W.

2010-01-01

Roč. 16, Suppl.2 (2010), s. 736-737 ISSN 1431-9276. [Microscopy and Microanalysis 2010. Portland, 01.08.2010-05.08.2010] R&D Projects: GA MŠk(CZ) LC06063; GA MŠk(CZ) ME09010; GA MŠk(CZ) MEB090910; GA ČR(CZ) GA304/09/0733 Institutional research plan: CEZ:AV0Z50110509 Keywords : capillary length * confocal microscopy * image analysis Subject RIV: EA - Cell Biology Impact factor: 2.179, year: 2010

A near-infrared confocal scanner

International Nuclear Information System (INIS)

Lee, Seungwoo; Yoo, Hongki

2014-01-01

In the semiconductor industry, manufacturing of three-dimensional (3D) packages or 3D integrated circuits is a high-performance technique that requires combining several functions in a small volume. Through-silicon vias, which are vertical electrical connections extending through a wafer, can be used to direct signals between stacked chips, thus increasing areal density by stacking and connecting multiple patterned chips. While defect detection is essential in the semiconductor manufacturing process, it is difficult to identify defects within a wafer or to monitor the bonding results between bonded surfaces because silicon and many other semiconductor materials are opaque to visible wavelengths. In this context, near-infrared (NIR) imaging is a promising non-destructive method to detect defects within silicon chips, to inspect bonding between chips and to monitor the chip alignment since NIR transmits through silicon. In addition, a confocal scanner provides high-contrast, optically-sectioned images of the specimen due to its ability to reject out-of-focus noise. In this study, we report an NIR confocal scanner that rapidly acquires high-resolution images with a large field of view through silicon. Two orthogonal line-scanning images can be acquired without rotating the system or the specimen by utilizing two orthogonally configured resonant scanning mirrors. This NIR confocal scanner can be efficiently used as an in-line inspection system when manufacturing semiconductor devices by rapidly detecting defects on and beneath the surface. (paper)

Diagnostic accuracy of confocal microscopy imaging vs. punch biopsy for diagnosing and subtyping basal cell carcinoma

NARCIS (Netherlands)

Kadouch, D. J.; Leeflang, M. M.; Elshot, Y. S.; Longo, C.; Ulrich, M.; van der Wal, A. C.; Wolkerstorfer, A.; Bekkenk, M. W.; de Rie, M. A.

2017-01-01

BackgroundIn vivo reflectance confocal microscopy (RCM) is a promising non-invasive skin imaging technique that could facilitate early diagnosis of basal cell carcinoma (BCC) instead of routine punch biopsies. However, the clinical value and utility of RCM vs. a punch biopsy in diagnosing and

Self-interference fluorescence microscopy with three-phase detection for depth-resolved confocal epi-fluorescence imaging.

Science.gov (United States)

Braaf, Boy; de Boer, Johannes F

2017-03-20

Three-dimensional confocal fluorescence imaging of in vivo tissues is challenging due to sample motion and limited imaging speeds. In this paper a novel method is therefore presented for scanning confocal epi-fluorescence microscopy with instantaneous depth-sensing based on self-interference fluorescence microscopy (SIFM). A tabletop epi-fluorescence SIFM setup was constructed with an annular phase plate in the emission path to create a spectral self-interference signal that is phase-dependent on the axial position of a fluorescent sample. A Mach-Zehnder interferometer based on a 3 × 3 fiber-coupler was developed for a sensitive phase analysis of the SIFM signal with three photon-counter detectors instead of a spectrometer. The Mach-Zehnder interferometer created three intensity signals that alternately oscillated as a function of the SIFM spectral phase and therefore encoded directly for the axial sample position. Controlled axial translation of fluorescent microsphere layers showed a linear dependence of the SIFM spectral phase with sample depth over axial image ranges of 500 µm and 80 µm (3.9 × Rayleigh range) for 4 × and 10 × microscope objectives respectively. In addition, SIFM was in good agreement with optical coherence tomography depth measurements on a sample with indocyanine green dye filled capillaries placed at multiple depths. High-resolution SIFM imaging applications are demonstrated for fluorescence angiography on a dye-filled capillary blood vessel phantom and for autofluorescence imaging on an ex vivo fly eye.

Exploiting Microwave Imaging Methods for Real-Time Monitoring of Thermal Ablation

Directory of Open Access Journals (Sweden)

Rosa Scapaticci

2017-01-01

Full Text Available Microwave thermal ablation is a cancer treatment that exploits local heating caused by a microwave electromagnetic field to induce coagulative necrosis of tumor cells. Recently, such a technique has significantly progressed in the clinical practice. However, its effectiveness would dramatically improve if paired with a noninvasive system for the real-time monitoring of the evolving dimension and shape of the thermally ablated area. In this respect, microwave imaging can be a potential candidate to monitor the overall treatment evolution in a noninvasive way, as it takes direct advantage from the dependence of the electromagnetic properties of biological tissues from temperature. This paper explores such a possibility by presenting a proof of concept validation based on accurate simulated imaging experiments, run with respect to a scenario that mimics an ex vivo experimental setup. In particular, two model-based inversion algorithms are exploited to tackle the imaging task. These methods provide independent results in real-time and their integration improves the quality of the overall tracking of the variations occurring in the target and surrounding regions.

A microwave-assisted solution combustion synthesis to produce europium-doped calcium phosphate nanowhiskers for bioimaging applications.

Science.gov (United States)

Wagner, Darcy E; Eisenmann, Kathryn M; Nestor-Kalinoski, Andrea L; Bhaduri, Sarit B

2013-09-01

Biocompatible nanoparticles possessing fluorescent properties offer attractive possibilities for multifunctional bioimaging and/or drug and gene delivery applications. Many of the limitations with current imaging systems center on the properties of the optical probes in relation to equipment technical capabilities. Here we introduce a novel high aspect ratio and highly crystalline europium-doped calcium phosphate nanowhisker produced using a simple microwave-assisted solution combustion synthesis method for use as a multifunctional bioimaging probe. X-ray diffraction confirmed the material phase as europium-doped hydroxyapatite. Fluorescence emission and excitation spectra and their corresponding peaks were identified using spectrofluorimetry and validated with fluorescence, confocal and multiphoton microscopy. The nanowhiskers were found to exhibit red and far red wavelength fluorescence under ultraviolet excitation with an optimal peak emission of 696 nm achieved with a 350 nm excitation. Relatively narrow emission bands were observed, which may permit their use in multicolor imaging applications. Confocal and multiphoton microscopy confirmed that the nanoparticles provide sufficient intensity to be utilized in imaging applications. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Characterization of LiF-based soft X-ray imaging detectors by confocal fluorescence microscopy

International Nuclear Information System (INIS)

Bonfigli, F; Gaudio, P; Lupelli, I; Nichelatti, E; Richetta, M; Vincenti, M A; Montereali, R M

2010-01-01

X-ray microscopy represents a powerful tool to obtain images of samples with very high spatial resolution. The main limitation of this technique is represented by the poor spatial resolution of standard imaging detectors. We proposed an innovative high-performance X-ray imaging detector based on the visible photoluminescence of colour centres in lithium fluoride. In this work, a confocal microscope in fluorescence mode was used to characterize LiF-based imaging detectors measuring CC integrated visible fluorescence signals of LiF crystals and films (grown on several kinds of substrates) irradiated by soft X-rays produced by a laser plasma source in different exposure conditions. The results are compared with the CC photoluminescence spectra measured on the same samples and discussed.

A linear programming approach to reconstructing subcellular structures from confocal images for automated generation of representative 3D cellular models.

Science.gov (United States)

Wood, Scott T; Dean, Brian C; Dean, Delphine

2013-04-01

This paper presents a novel computer vision algorithm to analyze 3D stacks of confocal images of fluorescently stained single cells. The goal of the algorithm is to create representative in silico model structures that can be imported into finite element analysis software for mechanical characterization. Segmentation of cell and nucleus boundaries is accomplished via standard thresholding methods. Using novel linear programming methods, a representative actin stress fiber network is generated by computing a linear superposition of fibers having minimum discrepancy compared with an experimental 3D confocal image. Qualitative validation is performed through analysis of seven 3D confocal image stacks of adherent vascular smooth muscle cells (VSMCs) grown in 2D culture. The presented method is able to automatically generate 3D geometries of the cell's boundary, nucleus, and representative F-actin network based on standard cell microscopy data. These geometries can be used for direct importation and implementation in structural finite element models for analysis of the mechanics of a single cell to potentially speed discoveries in the fields of regenerative medicine, mechanobiology, and drug discovery. Copyright © 2012 Elsevier B.V. All rights reserved.

3-Dimensional Iterative Forward Model for Microwave Imaging

DEFF Research Database (Denmark)

Kim, Oleksiy S.; Meincke, Peter

2006-01-01

The efficient solution of a forward scattering problem is the key point in nonlinear inversion schemes associated with microwave imaging. In this paper the solution is presented for the volume integral equation based on the method of moments (MoM) and accelerated with the adaptive integral method...

Utilization of multiple frequencies in 3D nonlinear microwave imaging

DEFF Research Database (Denmark)

Jensen, Peter Damsgaard; Rubæk, Tonny; Mohr, Johan Jacob

2012-01-01

The use of multiple frequencies in a nonlinear microwave algorithm is considered. Using multiple frequencies allows for obtaining the improved resolution available at the higher frequencies while retaining the regularizing effects of the lower frequencies. However, a number of different challenges...... at lower frequencies are used as starting guesses for reconstructions at higher frequencies. The performance is illustrated using simulated 2-D data and data obtained with the 3-D DTU microwave imaging system....

Confocal fluorescence microscopy for rapid evaluation of invasive tumor cellularity of inflammatory breast carcinoma core needle biopsies.

Science.gov (United States)

Dobbs, Jessica; Krishnamurthy, Savitri; Kyrish, Matthew; Benveniste, Ana Paula; Yang, Wei; Richards-Kortum, Rebecca

2015-01-01

Tissue sampling is a problematic issue for inflammatory breast carcinoma, and immediate evaluation following core needle biopsy is needed to evaluate specimen adequacy. We sought to determine if confocal fluorescence microscopy provides sufficient resolution to evaluate specimen adequacy by comparing invasive tumor cellularity estimated from standard histologic images to invasive tumor cellularity estimated from confocal images of breast core needle biopsy specimens. Grayscale confocal fluorescence images of breast core needle biopsy specimens were acquired following proflavine application. A breast-dedicated pathologist evaluated invasive tumor cellularity in histologic images with hematoxylin and eosin staining and in grayscale and false-colored confocal images of cores. Agreement between cellularity estimates was quantified using a kappa coefficient. 23 cores from 23 patients with suspected inflammatory breast carcinoma were imaged. Confocal images were acquired in an average of less than 2 min per core. Invasive tumor cellularity estimated from histologic and grayscale confocal images showed moderate agreement by kappa coefficient: κ = 0.48 ± 0.09 (p confocal images require less than 2 min for acquisition and allow for evaluation of invasive tumor cellularity in breast core needle biopsy specimens with moderate agreement to histologic images. We show that confocal fluorescence microscopy can be performed immediately following specimen acquisition and could indicate the need for additional biopsies at the initial visit.

Model-based microwave image reconstruction: simulations and experiments

International Nuclear Information System (INIS)

Ciocan, Razvan; Jiang Huabei

2004-01-01

We describe an integrated microwave imaging system that can provide spatial maps of dielectric properties of heterogeneous media with tomographically collected data. The hardware system (800-1200 MHz) was built based on a lock-in amplifier with 16 fixed antennas. The reconstruction algorithm was implemented using a Newton iterative method with combined Marquardt-Tikhonov regularizations. System performance was evaluated using heterogeneous media mimicking human breast tissue. Finite element method coupled with the Bayliss and Turkel radiation boundary conditions were applied to compute the electric field distribution in the heterogeneous media of interest. The results show that inclusions embedded in a 76-diameter background medium can be quantitatively reconstructed from both simulated and experimental data. Quantitative analysis of the microwave images obtained suggests that an inclusion of 14 mm in diameter is the smallest object that can be fully characterized presently using experimental data, while objects as small as 10 mm in diameter can be quantitatively resolved with simulated data

SU-F-T-665: Confocal Microscopy Imaging of Cell Cycle Distribution in Cells Treated with Pegylated Gold Nanoshells

Energy Technology Data Exchange (ETDEWEB)

Sadetaporn, D [Rice University, Houston, TX (United States); The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Flint, D; McFadden, C; Sawakuchi, G [The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Asaithamby, A [UT Southwestern Medical Center, Dallas, TX (United States)

2016-06-15

Purpose: To use confocal microscopy to distinguish cells in different phases of the cell cycle before and after treatment with pegylated gold nanoshells (PEG-AuNSs). Methods: Transfected fibrosarcoma cells (HT1080-EYFP-53BP1-FUCCI) were cultured in T-25 flasks and seeded in glass bottom dishes. These cells express the fluorescent probe AmCyan during the G2/S phases of the cell cycle, mCherry during the G1 phase, and EYFP tagged to the DNA repair protein 53BP1. After allowing cells 4 h to adhere to dishes, PEG-AuNS (Nanospectra Biosciences, Houston, TX) at a concentration of 0.15 OD were administered. At time points of 8, 16 and 24 h following treatment, the PEG-AuNS-treated and control samples were washed with phosphate buffered saline (PBS) and fixed using 4% paraformaldehyde in PBS. Samples were imaged with an Olympus FV1200 confocal microscope using 473, 543, and 641 nm excitation lasers. We used band-pass filters to select AmCyan and mCherry fluorescence. Reflection from the 641 nm laser was used to detect PEG-AuNSs. Z-stack images were analyzed to assess cell cycle distribution through fluorescent probe expression. Live cells were imaged after PEG-AuNS treatment using a confocal microscope with a stage top CO2 incubator. Results: We were able to obtain high-resolution images of cells with internalized AuNSs. We were also able to distinguish cells in different phases of the cell cycle. Conclusion: This work demonstrates a new assay to investigate the effect of AuNSs on the cell cycle phase in live cells. Future work will employ confocal microscopy and flow cytometry to focus on effects of AuNS treatment on cell cycle distribution. This research was supported by the Sister Institution Network Fund and the Center for Radiation Oncology Research at The University of Texas MD Anderson Cancer Center and Cancer Prevention and Research Institute of Texas. Gabriel Sawakuchi has research support from Elekta Inc.

SU-F-T-665: Confocal Microscopy Imaging of Cell Cycle Distribution in Cells Treated with Pegylated Gold Nanoshells

International Nuclear Information System (INIS)

Sadetaporn, D; Flint, D; McFadden, C; Sawakuchi, G; Asaithamby, A

2016-01-01

Purpose: To use confocal microscopy to distinguish cells in different phases of the cell cycle before and after treatment with pegylated gold nanoshells (PEG-AuNSs). Methods: Transfected fibrosarcoma cells (HT1080-EYFP-53BP1-FUCCI) were cultured in T-25 flasks and seeded in glass bottom dishes. These cells express the fluorescent probe AmCyan during the G2/S phases of the cell cycle, mCherry during the G1 phase, and EYFP tagged to the DNA repair protein 53BP1. After allowing cells 4 h to adhere to dishes, PEG-AuNS (Nanospectra Biosciences, Houston, TX) at a concentration of 0.15 OD were administered. At time points of 8, 16 and 24 h following treatment, the PEG-AuNS-treated and control samples were washed with phosphate buffered saline (PBS) and fixed using 4% paraformaldehyde in PBS. Samples were imaged with an Olympus FV1200 confocal microscope using 473, 543, and 641 nm excitation lasers. We used band-pass filters to select AmCyan and mCherry fluorescence. Reflection from the 641 nm laser was used to detect PEG-AuNSs. Z-stack images were analyzed to assess cell cycle distribution through fluorescent probe expression. Live cells were imaged after PEG-AuNS treatment using a confocal microscope with a stage top CO2 incubator. Results: We were able to obtain high-resolution images of cells with internalized AuNSs. We were also able to distinguish cells in different phases of the cell cycle. Conclusion: This work demonstrates a new assay to investigate the effect of AuNSs on the cell cycle phase in live cells. Future work will employ confocal microscopy and flow cytometry to focus on effects of AuNS treatment on cell cycle distribution. This research was supported by the Sister Institution Network Fund and the Center for Radiation Oncology Research at The University of Texas MD Anderson Cancer Center and Cancer Prevention and Research Institute of Texas. Gabriel Sawakuchi has research support from Elekta Inc.

Low-noise heterodyne receiver for electron cyclotron emission imaging and microwave imaging reflectometry

Energy Technology Data Exchange (ETDEWEB)

Tobias, B., E-mail: bjtobias@pppl.gov [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Domier, C. W.; Luhmann, N. C.; Luo, C.; Mamidanna, M.; Phan, T.; Pham, A.-V.; Wang, Y. [University of California at Davis, Davis, California 95616 (United States)

2016-11-15

The critical component enabling electron cyclotron emission imaging (ECEI) and microwave imaging reflectometry (MIR) to resolve 2D and 3D electron temperature and density perturbations is the heterodyne imaging array that collects and downconverts radiated emission and/or reflected signals (50–150 GHz) to an intermediate frequency (IF) band (e.g. 0.1–18 GHz) that can be transmitted by a shielded coaxial cable for further filtering and detection. New circuitry has been developed for this task, integrating gallium arsenide (GaAs) monolithic microwave integrated circuits (MMICs) mounted on a liquid crystal polymer (LCP) substrate. The improved topology significantly increases electromagnetic shielding from out-of-band interference, leads to 10× improvement in the signal-to-noise ratio, and dramatic cost savings through integration. The current design, optimized for reflectometry and edge radiometry on mid-sized tokamaks, has demonstrated >20 dB conversion gain in upper V-band (60-75 GHz). Implementation of the circuit in a multi-channel electron cyclotron emission imaging (ECEI) array will improve the diagnosis of edge-localized modes and fluctuations of the high-confinement, or H-mode, pedestal.

Fungal keratitis - improving diagnostics by confocal microscopy

DEFF Research Database (Denmark)

Nielsen, Esben; Heegaard, S; Prause, J U

2013-01-01

Purpose: Introducing a simple image grading system to support the interpretation of in vivo confocal microscopy (IVCM) images in filamentous fungal keratitis. Setting: Clinical and confocal studies took place at the Department of Ophthalmology, Aarhus University Hospital, Denmark. Histopathological...... analysis was performed at the Eye Pathology Institute, Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark. Methods: A recent series of consecutive patients with filamentous fungal keratitis is presented to demonstrate the results from in-house IVCM. Based upon our experience...... with IVCM and previously published images, we composed a grading system for interpreting IVCM images of filamentous fungal keratitis. Results: A recent case series of filamentous fungal keratitis from 2011 to 2012 was examined. There were 3 male and 3 female patients. Mean age was 44.5 years (range 12...

Microwave Technology for Brain Imaging and Monitoring: Physical Foundations, Potential and Limitations

DEFF Research Database (Denmark)

Scapaticci, Rosa; Bjelogrlic, Mina; Tobon Vasquez, Jorge

2018-01-01

This chapter provides an introduction to the physical principles underlying the adoption of microwave technology as a biomedical imaging modality for diagnosis and follow-up of neurological diseases and injuries (e.g., stroke, haematoma). In particular, a theoretical analysis, supported...... by numerical simulations and experiments, will be given to describe the physical constraints that arise in this kind of application and the relevant limitations. In addition, we discuss the main aspects to be faced when implementing microwave imaging technology in a clinical scenario, by exploiting a design...

Probe-based confocal laser endomicroscopy (pCLE) - a new imaging technique for in situ localization of spermatozoa.

Science.gov (United States)

Trottmann, Matthias; Stepp, Herbert; Sroka, Ronald; Heide, Michael; Liedl, Bernhard; Reese, Sven; Becker, Armin J; Stief, Christian G; Kölle, Sabine

2015-05-01

In azoospermic patients, spermatozoa are routinely obtained by testicular sperm extraction (TESE). However, success rates of this technique are moderate, because the site of excision of testicular tissue is determined arbitrarily. Therefore the aim of this study was to establish probe-based laser endomicroscopy (pCLE) a noval biomedical imaging technique, which provides the opportunity of non-invasive, real-time visualisation of tissue at histological resolution. Using pCLE we clearly visualized longitudinal and horizontal views of the tubuli seminiferi contorti and localized vital spermatozoa. Obtained images and real-time videos were subsequently compared with confocal laser scanning microscopy (CLSM) of spermatozoa and tissues, respectively. Comparative visualization of single native Confocal laser scanning microscopy (CLSM, left) and probe-based laser endomicroscopy (pCLE, right) using Pro Flex(TM) UltraMini O after staining with acriflavine. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cryogenic microwave imaging of metal–insulator transition in doped silicon

KAUST Repository

Kundhikanjana, Worasom; Lai, Keji; Kelly, Michael A.; Shen, Zhi-Xun

2011-01-01

We report the instrumentation and experimental results of a cryogenic scanning microwave impedance microscope. The microwave probe and the scanning stage are located inside the variable temperature insert of a helium cryostat. Microwave signals in the distance modulation mode are used for monitoring the tip-sample distance and adjusting the phase of the two output channels. The ability to spatially resolve the metal-insulator transition in a doped silicon sample is demonstrated. The data agree with a semiquantitative finite element simulation. Effects of the thermal energy and electric fields on local charge carriers can be seen in the images taken at different temperatures and dc biases. © 2011 American Institute of Physics.

Multispectral confocal microscopy images and artificial neural nets to monitor the photosensitizer uptake and degradation in Candida albicans cells

Science.gov (United States)

Romano, Renan A.; Pratavieira, Sebastião.; da Silva, Ana P.; Kurachi, Cristina; Guimarães, Francisco E. G.

2017-07-01

This study clearly demonstrates that multispectral confocal microscopy images analyzed by artificial neural networks provides a powerful tool to real-time monitoring photosensitizer uptake, as well as photochemical transformations occurred.

Digital differential confocal microscopy based on spatial shift transformation.

Science.gov (United States)

Liu, J; Wang, Y; Liu, C; Wilson, T; Wang, H; Tan, J

2014-11-01

Differential confocal microscopy is a particularly powerful surface profilometry technique in industrial metrology due to its high axial sensitivity and insensitivity to noise. However, the practical implementation of the technique requires the accurate positioning of point detectors in three-dimensions. We describe a simple alternative based on spatial transformation of a through-focus series of images obtained from a homemade beam scanning confocal microscope. This digital differential confocal microscopy approach is described and compared with the traditional Differential confocal microscopy approach. The ease of use of the digital differential confocal microscopy system is illustrated by performing measurements on a 3D standard specimen. © 2014 The Authors Journal of Microscopy © 2014 Royal Microscopical Society.

Aspect-Aided Dynamic Non-Negative Sparse Representation-Based Microwave Image Classification

Directory of Open Access Journals (Sweden)

Xinzheng Zhang

2016-09-01

Full Text Available Classification of target microwave images is an important application in much areas such as security, surveillance, etc. With respect to the task of microwave image classification, a recognition algorithm based on aspect-aided dynamic non-negative least square (ADNNLS sparse representation is proposed. Firstly, an aspect sector is determined, the center of which is the estimated aspect angle of the testing sample. The training samples in the aspect sector are divided into active atoms and inactive atoms by smooth self-representative learning. Secondly, for each testing sample, the corresponding active atoms are selected dynamically, thereby establishing dynamic dictionary. Thirdly, the testing sample is represented with ℓ 1 -regularized non-negative sparse representation under the corresponding dynamic dictionary. Finally, the class label of the testing sample is identified by use of the minimum reconstruction error. Verification of the proposed algorithm was conducted using the Moving and Stationary Target Acquisition and Recognition (MSTAR database which was acquired by synthetic aperture radar. Experiment results validated that the proposed approach was able to capture the local aspect characteristics of microwave images effectively, thereby improving the classification performance.

Microwave imaging of spinning object using orbital angular momentum

Science.gov (United States)

Liu, Kang; Li, Xiang; Gao, Yue; Wang, Hongqiang; Cheng, Yongqiang

2017-09-01

The linear Doppler shift used for the detection of a spinning object becomes significantly weakened when the line of sight (LOS) is perpendicular to the object, which will result in the failure of detection. In this paper, a new detection and imaging technique for spinning objects is developed. The rotational Doppler phenomenon is observed by using the microwave carrying orbital angular momentum (OAM). To converge the radiation energy on the area where objects might exist, the generation method of OAM beams is proposed based on the frequency diversity principle, and the imaging model is derived accordingly. The detection method of the rotational Doppler shift and the imaging approach of the azimuthal profiles are proposed, which are verified by proof-of-concept experiments. Simulation and experimental results demonstrate that OAM beams can still be used to obtain the azimuthal profiles of spinning objects even when the LOS is perpendicular to the object. This work remedies the insufficiency in existing microwave sensing technology and offers a new solution to the object identification problem.

Inter-rater and intra-rater agreement of confocal microscopy imaging in diagnosing and subtyping basal cell carcinoma

NARCIS (Netherlands)

Kadouch, D. J.; van Haersma de With, A.; Elshot, Y. S.; Peppelman, M.; Bekkenk, M. W.; Wolkerstorfer, A.; Eekhout, I.; Prinsen, C. A. C.; de Rie, M. A.

2017-01-01

Reflectance confocal microscopy (RCM) imaging can be used to diagnose and subtype basal cell carcinoma (BCC) but relies on individual morphologic pattern recognition that might vary among users. We assessed the inter-rater and intra-rater agreement of RCM in correctly diagnosing and subtyping BCC.

Evaluation of Yogurt Microstructure Using Confocal Laser Scanning Microscopy and Image Analysis.

Science.gov (United States)

Skytte, Jacob L; Ghita, Ovidiu; Whelan, Paul F; Andersen, Ulf; Møller, Flemming; Dahl, Anders B; Larsen, Rasmus

2015-06-01

The microstructure of protein networks in yogurts defines important physical properties of the yogurt and hereby partly its quality. Imaging this protein network using confocal scanning laser microscopy (CSLM) has shown good results, and CSLM has become a standard measuring technique for fermented dairy products. When studying such networks, hundreds of images can be obtained, and here image analysis methods are essential for using the images in statistical analysis. Previously, methods including gray level co-occurrence matrix analysis and fractal analysis have been used with success. However, a range of other image texture characterization methods exists. These methods describe an image by a frequency distribution of predefined image features (denoted textons). Our contribution is an investigation of the choice of image analysis methods by performing a comparative study of 7 major approaches to image texture description. Here, CSLM images from a yogurt fermentation study are investigated, where production factors including fat content, protein content, heat treatment, and incubation temperature are varied. The descriptors are evaluated through nearest neighbor classification, variance analysis, and cluster analysis. Our investigation suggests that the texton-based descriptors provide a fuller description of the images compared to gray-level co-occurrence matrix descriptors and fractal analysis, while still being as applicable and in some cases as easy to tune. © 2015 Institute of Food Technologists®

Extended Special Sensor Microwave Imager (SSM/I) Temperature Data Record (TDR) in netCDF

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Special Sensor Microwave Imager (SSM/I) is a seven-channel linearly polarized passive microwave radiometer that operates at frequencies of 19.36 (vertically and...

Extended Special Sensor Microwave Imager (SSM/I) Sensor Data Record (SDR) in netCDF

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Special Sensor Microwave Imager (SSM/I) is a seven-channel linearly polarized passive microwave radiometer that operates at frequencies of 19.36 (vertically and...

Re-scan confocal microscopy: scanning twice for better resolution.

Science.gov (United States)

De Luca, Giulia M R; Breedijk, Ronald M P; Brandt, Rick A J; Zeelenberg, Christiaan H C; de Jong, Babette E; Timmermans, Wendy; Azar, Leila Nahidi; Hoebe, Ron A; Stallinga, Sjoerd; Manders, Erik M M

2013-01-01

We present a new super-resolution technique, Re-scan Confocal Microscopy (RCM), based on standard confocal microscopy extended with an optical (re-scanning) unit that projects the image directly on a CCD-camera. This new microscope has improved lateral resolution and strongly improved sensitivity while maintaining the sectioning capability of a standard confocal microscope. This simple technology is typically useful for biological applications where the combination high-resolution and high-sensitivity is required.

Optical sectioning using a digital Fresnel incoherent-holography-based confocal imaging system

OpenAIRE

Kelner, Roy; Katz, Barak; Rosen, Joseph

2014-01-01

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.

Quantification of confocal fluorescence microscopy for the detection of cervical intraepithelial neoplasia.

Science.gov (United States)

Sheikhzadeh, Fahime; Ward, Rabab K; Carraro, Anita; Chen, Zhao Yang; van Niekerk, Dirk; Miller, Dianne; Ehlen, Tom; MacAulay, Calum E; Follen, Michele; Lane, Pierre M; Guillaud, Martial

2015-10-24

Cervical cancer remains a major health problem, especially in developing countries. Colposcopic examination is used to detect high-grade lesions in patients with a history of abnormal pap smears. New technologies are needed to improve the sensitivity and specificity of this technique. We propose to test the potential of fluorescence confocal microscopy to identify high-grade lesions. We examined the quantification of ex vivo confocal fluorescence microscopy to differentiate among normal cervical tissue, low-grade Cervical Intraepithelial Neoplasia (CIN), and high-grade CIN. We sought to (1) quantify nuclear morphology and tissue architecture features by analyzing images of cervical biopsies; and (2) determine the accuracy of high-grade CIN detection via confocal microscopy relative to the accuracy of detection by colposcopic impression. Forty-six biopsies obtained from colposcopically normal and abnormal cervical sites were evaluated. Confocal images were acquired at different depths from the epithelial surface and histological images were analyzed using in-house software. The features calculated from the confocal images compared well with those features obtained from the histological images and histopathological reviews of the specimens (obtained by a gynecologic pathologist). The correlations between two of these features (the nuclear-cytoplasmic ratio and the average of three nearest Delaunay-neighbors distance) and the grade of dysplasia were higher than that of colposcopic impression. The sensitivity of detecting high-grade dysplasia by analysing images collected at the surface of the epithelium, and at 15 and 30 μm below the epithelial surface were respectively 100, 100, and 92 %. Quantitative analysis of confocal fluorescence images showed its capacity for discriminating high-grade CIN lesions vs. low-grade CIN lesions and normal tissues, at different depth of imaging. This approach could be used to help clinicians identify high-grade CIN in clinical

Confocal imaging of protein distributions in porous silicon optical structures

International Nuclear Information System (INIS)

De Stefano, Luca; D'Auria, Sabato

2007-01-01

The performances of porous silicon optical biosensors depend strongly on the arrangement of the biological probes into their sponge-like structures: it is well known that in this case the sensing species do not fill the pores but instead cover their internal surface. In this paper, the direct imaging of labelled proteins into different porous silicon structures by using a confocal laser microscope is reported. The distribution of the biological matter in the nanostructured material follows a Gaussian behaviour which is typical of the diffusion process in the porous media but with substantial differences between a porous silicon monolayer and a multilayer such as a Bragg mirror. Even if semi-quantitative, the results can be very useful in the design of the porous silicon based biosensing devices

Validating Intravascular Imaging with Serial Optical Coherence Tomography and Confocal Fluorescence Microscopy.

Science.gov (United States)

Tardif, Pier-Luc; Bertrand, Marie-Jeanne; Abran, Maxime; Castonguay, Alexandre; Lefebvre, Joël; Stähli, Barbara E; Merlet, Nolwenn; Mihalache-Avram, Teodora; Geoffroy, Pascale; Mecteau, Mélanie; Busseuil, David; Ni, Feng; Abulrob, Abedelnasser; Rhéaume, Éric; L'Allier, Philippe; Tardif, Jean-Claude; Lesage, Frédéric

2016-12-15

Atherosclerotic cardiovascular diseases are characterized by the formation of a plaque in the arterial wall. Intravascular ultrasound (IVUS) provides high-resolution images allowing delineation of atherosclerotic plaques. When combined with near infrared fluorescence (NIRF), the plaque can also be studied at a molecular level with a large variety of biomarkers. In this work, we present a system enabling automated volumetric histology imaging of excised aortas that can spatially correlate results with combined IVUS/NIRF imaging of lipid-rich atheroma in cholesterol-fed rabbits. Pullbacks in the rabbit aortas were performed with a dual modality IVUS/NIRF catheter developed by our group. Ex vivo three-dimensional (3D) histology was performed combining optical coherence tomography (OCT) and confocal fluorescence microscopy, providing high-resolution anatomical and molecular information, respectively, to validate in vivo findings. The microscope was combined with a serial slicer allowing for the imaging of the whole vessel automatically. Colocalization of in vivo and ex vivo results is demonstrated. Slices can then be recovered to be tested in conventional histology.

Optical sectioning using a digital Fresnel incoherent-holography-based confocal imaging system

Science.gov (United States)

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

Development of an add-on kit for scanning confocal microscopy (Conference Presentation)

Science.gov (United States)

Guo, Kaikai; Zheng, Guoan

2017-03-01

Scanning confocal microscopy is a standard choice for many fluorescence imaging applications in basic biomedical research. It is able to produce optically sectioned images and provide acquisition versatility to address many samples and application demands. However, scanning a focused point across the specimen limits the speed of image acquisition. As a result, scanning confocal microscope only works well with stationary samples. Researchers have performed parallel confocal scanning using digital-micromirror-device (DMD), which was used to project a scanning multi-point pattern across the sample. The DMD based parallel confocal systems increase the imaging speed while maintaining the optical sectioning ability. In this paper, we report the development of an add-on kit for high-speed and low-cost confocal microscopy. By adapting this add-on kit to an existing regular microscope, one can convert it into a confocal microscope without significant hardware modifications. Compared with current DMD-based implementations, the reported approach is able to recover multiple layers along the z axis simultaneously. It may find applications in wafer inspection and 3D metrology of semiconductor circuit. The dissemination of the proposed add-on kit under $1000 budget could also lead to new types of experimental designs for biological research labs, e.g., cytology analysis in cell culture experiments, genetic studies on multicellular organisms, pharmaceutical drug profiling, RNA interference studies, investigation of microbial communities in environmental systems, and etc.

Evaluating ex vivo fluorescence confocal microscopy images of basal cell carcinomas in Mohs excised tissue.

Science.gov (United States)

Longo, C; Rajadhyaksha, M; Ragazzi, M; Nehal, K; Gardini, S; Moscarella, E; Lallas, A; Zalaudek, I; Piana, S; Argenziano, G; Pellacani, G

2014-09-01

Fluorescence confocal microscopy (FCM) is an emerging technology for rapid imaging of excised tissue, without the need for frozen- or fixed-section processing. Basal cell carcinomas (BCCs) can be detected in Mohs excisions although few studies have described the major BCC findings as seen on FCM. To describe the major BCC findings of excised tissue during Mohs surgery and to correlate them with histopathology. Freshly excised tumours and frozen-thawed discarded tissue of BCC during Mohs surgery were analysed by means of FCM. A side-by-side correlation between FCM images and histological sections was performed. The FCM features of overlying skin and adnexal structures were also described. Sixty-four BCC cases were analysed. Distinct BCC types appeared unique in terms of shape and size of tumour islands [bigger in nodular (18/25), smaller and rounded in micronodular (7/7) and tiny cords for infiltrative ones (24/30)] and for the presence of clefting, palisading and increased nucleus/cytoplasm ratio. An excellent correlation was found between FCM and histological findings (Cohen's κ statistics = 0·9). In six cases, the presence of sebaceous glands and intense stroma reaction represented possible confounders. Fluorescence confocal microscopy is a fast and new imaging technique that allows an excellent visualization of skin structures and BCC findings during Mohs surgery. © 2014 British Association of Dermatologists.

Compensation of inhomogeneous fluorescence signal distribution in 2D images acquired by confocal microscopy

Czech Academy of Sciences Publication Activity Database

Michálek, Jan; Čapek, Martin; Kubínová, Lucie

2011-01-01

Roč. 74, č. 9 (2011), s. 831-838 ISSN 1059-910X R&D Projects: GA ČR(CZ) GA102/08/0691; GA ČR(CZ) GA304/09/0733; GA MŠk(CZ) LC06063; GA MŠk(CZ) ME09010 Institutional research plan: CEZ:AV0Z50110509 Keywords : confocal laser scanning microscopy * image enhancement * morphology filters Subject RIV: JC - Computer Hardware ; Software Impact factor: 1.792, year: 2011

3D imaging of cement-based materials at submicron resolution by combining laser scanning confocal microscopy with serial sectioning.

Science.gov (United States)

Yio, M H N; Mac, M J; Wong, H S; Buenfeld, N R

2015-05-01

In this paper, we present a new method to reconstruct large volumes of nontransparent porous materials at submicron resolution. The proposed method combines fluorescence laser scanning confocal microscopy with serial sectioning to produce a series of overlapping confocal z-stacks, which are then aligned and stitched based on phase correlation. The method can be extended in the XY plane to further increase the overall image volume. Resolution of the reconstructed image volume does not degrade with increase in sample size. We have used the method to image cementitious materials, hardened cement paste and concrete and the results obtained show that the method is reliable. Possible applications of the method such as three-dimensional characterization of the pores and microcracks in hardened concrete, three-dimensional particle shape characterization of cementitious materials and three-dimensional characterization of other porous materials such as rocks and bioceramics are discussed. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

Microwave Sensors for Breast Cancer Detection.

Science.gov (United States)

Wang, Lulu

2018-02-23

Breast cancer is the leading cause of death among females, early diagnostic methods with suitable treatments improve the 5-year survival rates significantly. Microwave breast imaging has been reported as the most potential to become the alternative or additional tool to the current gold standard X-ray mammography for detecting breast cancer. The microwave breast image quality is affected by the microwave sensor, sensor array, the number of sensors in the array and the size of the sensor. In fact, microwave sensor array and sensor play an important role in the microwave breast imaging system. Numerous microwave biosensors have been developed for biomedical applications, with particular focus on breast tumor detection. Compared to the conventional medical imaging and biosensor techniques, these microwave sensors not only enable better cancer detection and improve the image resolution, but also provide attractive features such as label-free detection. This paper aims to provide an overview of recent important achievements in microwave sensors for biomedical imaging applications, with particular focus on breast cancer detection. The electric properties of biological tissues at microwave spectrum, microwave imaging approaches, microwave biosensors, current challenges and future works are also discussed in the manuscript.

High-speed adaptive optics line scan confocal retinal imaging for human eye.

Science.gov (United States)

Lu, Jing; Gu, Boyu; Wang, Xiaolin; Zhang, Yuhua

2017-01-01

Continuous and rapid eye movement causes significant intraframe distortion in adaptive optics high resolution retinal imaging. To minimize this artifact, we developed a high speed adaptive optics line scan confocal retinal imaging system. A high speed line camera was employed to acquire retinal image and custom adaptive optics was developed to compensate the wave aberration of the human eye's optics. The spatial resolution and signal to noise ratio were assessed in model eye and in living human eye. The improvement of imaging fidelity was estimated by reduction of intra-frame distortion of retinal images acquired in the living human eyes with frame rates at 30 frames/second (FPS), 100 FPS, and 200 FPS. The device produced retinal image with cellular level resolution at 200 FPS with a digitization of 512×512 pixels/frame in the living human eye. Cone photoreceptors in the central fovea and rod photoreceptors near the fovea were resolved in three human subjects in normal chorioretinal health. Compared with retinal images acquired at 30 FPS, the intra-frame distortion in images taken at 200 FPS was reduced by 50.9% to 79.7%. We demonstrated the feasibility of acquiring high resolution retinal images in the living human eye at a speed that minimizes retinal motion artifact. This device may facilitate research involving subjects with nystagmus or unsteady fixation due to central vision loss.

Confocal laser endomicroscopy for diagnosis and histomorphologic imaging of brain tumors in vivo.

Directory of Open Access Journals (Sweden)

Sebastian Foersch

Full Text Available Early detection and evaluation of brain tumors during surgery is crucial for accurate resection. Currently cryosections during surgery are regularly performed. Confocal laser endomicroscopy (CLE is a novel technique permitting in vivo histologic imaging with miniaturized endoscopic probes at excellent resolution. Aim of the current study was to evaluate CLE for in vivo diagnosis in different types and models of intracranial neoplasia. In vivo histomorphology of healthy brains and two different C6 glioma cell line allografts was evaluated in rats. One cell line expressed EYFP, the other cell line was used for staining with fluorescent dyes (fluorescein, acriflavine, FITC-dextran and Indocyanine green. To evaluate future application in patients, fresh surgical resection specimen of human intracranial tumors (n = 15 were examined (glioblastoma multiforme, meningioma, craniopharyngioma, acoustic neurinoma, brain metastasis, medulloblastoma, epidermoid tumor. Healthy brain tissue adjacent to the samples served as control. CLE yielded high-quality histomorphology of normal brain tissue and tumors. Different fluorescent agents revealed distinct aspects of tissue and cell structure (nuclear pattern, axonal pathways, hemorrhages. CLE discrimination of neoplastic from healthy brain tissue was easy to perform based on tissue and cellular architecture and resemblance with histopathology was excellent. Confocal laser endomicroscopy allows immediate in vivo imaging of normal and neoplastic brain tissue at high resolution. The technology might be transferred to scientific and clinical application in neurosurgery and neuropathology. It may become helpful to screen for tumor free margins and to improve the surgical resection of malignant brain tumors, and opens the door to in vivo molecular imaging of tumors and other neurologic disorders.

Progress in reflectance confocal microscopy for imaging oral tissues in vivo

Science.gov (United States)

Peterson, Gary; Zanoni, Daniella K.; Migliacci, Jocelyn; Cordova, Miguel; Rajadhyaksha, Milind; Patel, Snehal

2016-02-01

We report progress in development and feasibility testing of reflectance confocal microscopy (RCM) for imaging in the oral cavity of humans. We adapted a small rigid relay telescope (120mm long x 14mm diameter) and a small water immersion objective lens (12mm diameter, NA 0.7) to a commercial handheld RCM scanner (Vivascope 3000, Caliber ID, Rochester NY). This scanner is designed for imaging skin but we adapted the front end (the objective lens and the stepper motor that axially translates) for intra-oral use. This adaption required a new approach to address the loss of the automated stepper motor for acquisition of images in depth. A helical spring-like cap (with a coverslip to contact tissue) was designed for approximately 150 um of travel. Additionally other methods for focusing optics were designed and evaluated. The relay telescope optics is being tested in a clinical setting. With the capture of video and "video-mosaicing", extended areas can be imaged. The feasibility of imaging oral tissues was initially investigated in volunteers. RCM imaging in buccal mucosa in vivo shows nuclear and cellular detail in the epithelium and epithelial junction, and connective tissue and blood flow in the underlying lamina propria. Similar detail, including filiform and fungiform papillae, can be seen on the tongue in vivo. Clinical testing during head and neck surgery is now in progress and patients are being imaged for both normal tissue and cancerous margins in lip and tongue mucosa.

Metabolic changes of cultured DRG neurons induced by adenosine using confocal microscopy imaging

Science.gov (United States)

Zheng, Liqin; Huang, Yimei; Chen, Jiangxu; Wang, Yuhua; Yang, Hongqin; Zhang, Yanding; Xie, Shusen

2012-12-01

Adenosine exerts multiple effects on pain transmission in the peripheral nervous system. This study was performed to use confocal microscopy to evaluate whether adenosine could affect dorsal root ganglia (DRG) neurons in vitro and test which adenosine receptor mediates the effect of adenosine on DRG neurons. After adding adenosine with different concentration, we compared the metabolic changes by the real time imaging of calcium and mitochondria membrane potential using confocal microscopy. The results showed that the effect of 500 μM adenosine on the metabolic changes of DRG neurons was more significant than others. Furthermore, four different adenosine receptor antagonists were used to study which receptor mediated the influences of adenosine on the cultured DRG neurons. All adenosine receptor antagonists especially A1 receptor antagonist (DPCPX) had effect on the Ca2+ and mitochondria membrane potential dynamics of DRG neurons. The above studies demonstrated that the effect of adenosine which may be involved in the signal transmission on the sensory neurons was dose-dependent, and all the four adenosine receptors especially the A1R may mediate the transmission.

Integrated Photoacoustic and Fluorescence Confocal Microscopy

OpenAIRE

Wang, Yu; Maslov, Konstantin; Kim, Chulhong; Hu, Song; Wang, Lihong V.

2010-01-01

We have developed a dual-modality imaging system by integrating optical-resolution photoacoustic microscopy and fluorescence confocal microscopy to provide optical absorption and fluorescence contrasts simultaneously. By sharing the same laser source and objective lens, intrinsically registered photoacoustic and fluorescence images are acquired in a single scan. The micrometer resolution allows imaging of both blood and lymphatic vessels down to the capillary level. Simultaneous photoacoustic...

Real time detection of antibody-antigen interaction using a laser scanning confocal imaging-surface plasmon resonance system

International Nuclear Information System (INIS)

Zhang Hong-Yan; Yang Li-Quan; Ning Ting-Yin; Liu Wei-Min; Sun Jia-Yu; Wang Peng-Fei; Meng Lan; Nie Jia-Cai

2012-01-01

A laser scanning confocal imaging-surface plasmon resonance (LSCI-SPR) instrument integrated with a wavelength-dependent surface plasmon resonance (SPR) sensor and a laser scanning confocal microscopy (LSCM) is built to detect the bonding process of human IgG and fluorescent-labeled affinity purified antibodies in real time. The shifts of resonant wavelength at different reaction time stages are obtained by SPR, corresponding well with the changes of the fluorescence intensity collected by using LSCM. The instrument shows the merits of the combination and complementation of the SPR and LSCM, with such advantages as quantificational analysis, high spatial resolution and real time monitor, which are of great importance for practical applications in biosensor and life science. (general)

Microwave Breast Imaging System Prototype with Integrated Numerical Characterization

Directory of Open Access Journals (Sweden)

Mark Haynes

2012-01-01

Full Text Available The increasing number of experimental microwave breast imaging systems and the need to properly model them have motivated our development of an integrated numerical characterization technique. We use Ansoft HFSS and a formalism we developed previously to numerically characterize an S-parameter- based breast imaging system and link it to an inverse scattering algorithm. We show successful reconstructions of simple test objects using synthetic and experimental data. We demonstrate the sensitivity of image reconstructions to knowledge of the background dielectric properties and show the limits of the current model.

Parallel detection experiment of fluorescence confocal microscopy using DMD.

Science.gov (United States)

Wang, Qingqing; Zheng, Jihong; Wang, Kangni; Gui, Kun; Guo, Hanming; Zhuang, Songlin

2016-05-01

Parallel detection of fluorescence confocal microscopy (PDFCM) system based on Digital Micromirror Device (DMD) is reported in this paper in order to realize simultaneous multi-channel imaging and improve detection speed. DMD is added into PDFCM system, working to take replace of the single traditional pinhole in the confocal system, which divides the laser source into multiple excitation beams. The PDFCM imaging system based on DMD is experimentally set up. The multi-channel image of fluorescence signal of potato cells sample is detected by parallel lateral scanning in order to verify the feasibility of introducing the DMD into fluorescence confocal microscope. In addition, for the purpose of characterizing the microscope, the depth response curve is also acquired. The experimental result shows that in contrast to conventional microscopy, the DMD-based PDFCM system has higher axial resolution and faster detection speed, which may bring some potential benefits in the biology and medicine analysis. SCANNING 38:234-239, 2016. © 2015 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.

Dual-model automatic detection of nerve-fibres in corneal confocal microscopy images.

Science.gov (United States)

Dabbah, M A; Graham, J; Petropoulos, I; Tavakoli, M; Malik, R A

2010-01-01

Corneal Confocal Microscopy (CCM) imaging is a non-invasive surrogate of detecting, quantifying and monitoring diabetic peripheral neuropathy. This paper presents an automated method for detecting nerve-fibres from CCM images using a dual-model detection algorithm and compares the performance to well-established texture and feature detection methods. The algorithm comprises two separate models, one for the background and another for the foreground (nerve-fibres), which work interactively. Our evaluation shows significant improvement (p approximately 0) in both error rate and signal-to-noise ratio of this model over the competitor methods. The automatic method is also evaluated in comparison with manual ground truth analysis in assessing diabetic neuropathy on the basis of nerve-fibre length, and shows a strong correlation (r = 0.92). Both analyses significantly separate diabetic patients from control subjects (p approximately 0).

Clinical applications of corneal confocal microscopy

Directory of Open Access Journals (Sweden)

Mitra Tavakoli

2008-06-01

Full Text Available Mitra Tavakoli1, Parwez Hossain2, Rayaz A Malik11Division of Cardiovascular Medicine, University of Manchester and Manchester Royal Infirmary, Manchester, UK; 2University of Southampton, Southampton Eye Unit, Southampton General Hospital, Southampton, UKAbstract: Corneal confocal microscopy is a novel clinical technique for the study of corneal cellular structure. It provides images which are comparable to in-vitro histochemical techniques delineating corneal epithelium, Bowman’s layer, stroma, Descemet’s membrane and the corneal endothelium. Because, corneal confocal microscopy is a non invasive technique for in vivo imaging of the living cornea it has huge clinical potential to investigate numerous corneal diseases. Thus far it has been used in the detection and management of pathologic and infectious conditions, corneal dystrophies and ecstasies, monitoring contact lens induced corneal changes and for pre and post surgical evaluation (PRK, LASIK and LASEK, flap evaluations and Radial Keratotomy, and penetrating keratoplasty. Most recently it has been used as a surrogate for peripheral nerve damage in a variety of peripheral neuropathies and may have potential in acting as a surrogate marker for endothelial abnormalities.Keywords: corneal confocal microscopy, cornea, infective keratitis, corneal dystrophy, neuropathy

The effect of compression on clinical diagnosis of glaucoma based on non-analyzed confocal scanning laser ophthalmoscopy images

NARCIS (Netherlands)

Abramoff, M.D.

2006-01-01

Knowledge of the effect of compression of ophthalmic images on diagnostic reading is essential for effective tele-ophthalmology applications. It was therefore with great anticipation that I read the article “The Effect of Compression on Clinical Diagnosis of Glaucoma Based on Non-analyzed Confocal

Multimodal backside imaging of a microcontroller using confocal laser scanning and optical-beam-induced current imaging

Science.gov (United States)

Finkeldey, Markus; Göring, Lena; Schellenberg, Falk; Brenner, Carsten; Gerhardt, Nils C.; Hofmann, Martin

2017-02-01

Microscopy imaging with a single technology is usually restricted to a single contrast mechanism. Multimodal imaging is a promising technique to improve the structural information that could be obtained about a device under test (DUT). Due to the different contrast mechanisms of laser scanning microscopy (LSM), confocal laser scanning microscopy (CLSM) and optical beam induced current microscopy (OBICM), a combination could improve the detection of structures in integrated circuits (ICs) and helps to reveal their layout. While OBIC imaging is sensitive to the changes between differently doped areas and to semiconductor-metal transitions, CLSM imaging is mostly sensitive to changes in absorption and reflection. In this work we present the implementation of OBIC imaging into a CLSM. We show first results using industry standard Atmel microcontrollers (MCUs) with a feature size of about 250nm as DUTs. Analyzing these types of microcontrollers helps to improve in the field of side-channel attacks to find hardware Trojans, possible spots for laser fault attacks and for reverse engineering. For the experimental results the DUT is placed on a custom circuit board that allows us to measure the current while imaging it in our in-house built stage scanning microscope using a near infrared (NIR) laser diode as light source. The DUT is thinned and polished, allowing backside imaging through the Si-substrate. We demonstrate the possibilities using this optical setup by evaluating OBIC, LSM and CLSM images above and below the threshold of the laser source.

Nonlinear microwave imaging using Levenberg-Marquardt method with iterative shrinkage thresholding

KAUST Repository

Desmal, Abdulla; Bagci, Hakan

2014-01-01

Development of microwave imaging methods applicable in sparse investigation domains is becoming a research focus in computational electromagnetics (D.W. Winters and S.C. Hagness, IEEE Trans. Antennas Propag., 58(1), 145-154, 2010). This is simply due to the fact that sparse/sparsified domains naturally exist in many applications including remote sensing, medical imaging, crack detection, hydrocarbon reservoir exploration, and see-through-the-wall imaging.

Nonlinear microwave imaging using Levenberg-Marquardt method with iterative shrinkage thresholding

KAUST Repository

Desmal, Abdulla

2014-07-01

Development of microwave imaging methods applicable in sparse investigation domains is becoming a research focus in computational electromagnetics (D.W. Winters and S.C. Hagness, IEEE Trans. Antennas Propag., 58(1), 145-154, 2010). This is simply due to the fact that sparse/sparsified domains naturally exist in many applications including remote sensing, medical imaging, crack detection, hydrocarbon reservoir exploration, and see-through-the-wall imaging.

Evaluation of multichannel Wiener filters applied to fine resolution passive microwave images of first-year sea ice

Science.gov (United States)

Full, William E.; Eppler, Duane T.

1993-01-01

The effectivity of multichannel Wiener filters to improve images obtained with passive microwave systems was investigated by applying Wiener filters to passive microwave images of first-year sea ice. Four major parameters which define the filter were varied: the lag or pixel offset between the original and the desired scenes, filter length, the number of lines in the filter, and the weight applied to the empirical correlation functions. The effect of each variable on the image quality was assessed by visually comparing the results. It was found that the application of multichannel Wiener theory to passive microwave images of first-year sea ice resulted in visually sharper images with enhanced textural features and less high-frequency noise. However, Wiener filters induced a slight blocky grain to the image and could produce a type of ringing along scan lines traversing sharp intensity contrasts.

Ex Vivo (Fluorescence) Confocal Microscopy in Surgical Pathology: State of the Art.

Science.gov (United States)

Ragazzi, Moira; Longo, Caterina; Piana, Simonetta

2016-05-01

First developed in 1957, confocal microscopy is a powerful imaging tool that can be used to obtain near real-time reflected light images of untreated human tissue with nearly histologic resolution. Besides its research applications, in the last decades, confocal microscopy technology has been proposed as a useful device to improve clinical diagnosis, especially in ophthalmology, dermatology, and endomicroscopy settings, thanks to advances in instrument development. Compared with the wider use of the in vivo tissue assessment, ex vivo applications of confocal microscopy are not fully explored. A comprehensive review of the current literature was performed here, focusing on the reliable applications of ex vivo confocal microscopy in surgical pathology and on some potential evolutions of this new technique from pathologists' viewpoint.

Quantitative sub-surface and non-contact imaging using scanning microwave microscopy

International Nuclear Information System (INIS)

Gramse, Georg; Kasper, Manuel; Hinterdorfer, Peter; Brinciotti, Enrico; Rankl, Christian; Kienberger, Ferry; Lucibello, Andrea; Marcelli, Romolo; Patil, Samadhan B.; Giridharagopal, Rajiv

2015-01-01

The capability of scanning microwave microscopy for calibrated sub-surface and non-contact capacitance imaging of silicon (Si) samples is quantitatively studied at broadband frequencies ranging from 1 to 20 GHz. Calibrated capacitance images of flat Si test samples with varying dopant density (10 15 –10 19 atoms cm −3 ) and covered with dielectric thin films of SiO 2 (100–400 nm thickness) are measured to demonstrate the sensitivity of scanning microwave microscopy (SMM) for sub-surface imaging. Using standard SMM imaging conditions the dopant areas could still be sensed under a 400 nm thick oxide layer. Non-contact SMM imaging in lift-mode and constant height mode is quantitatively demonstrated on a 50 nm thick SiO 2 test pad. The differences between non-contact and contact mode capacitances are studied with respect to the main parameters influencing the imaging contrast, namely the probe tip diameter and the tip–sample distance. Finite element modelling was used to further analyse the influence of the tip radius and the tip–sample distance on the SMM sensitivity. The understanding of how the two key parameters determine the SMM sensitivity and quantitative capacitances represents an important step towards its routine application for non-contact and sub-surface imaging. (paper)

3D confocal Raman imaging of oil-rich emulsion from enzyme-assisted aqueous extraction of extruded soybean powder.

Science.gov (United States)

Wu, Longkun; Wang, Limin; Qi, Baokun; Zhang, Xiaonan; Chen, Fusheng; Li, Yang; Sui, Xiaonan; Jiang, Lianzhou

2018-05-30

The understanding of the structure morphology of oil-rich emulsion from enzyme-assisted extraction processing (EAEP) was a critical step to break the oil-rich emulsion structure in order to recover oil. Albeit EAEP method has been applied as an alternative way to conventional solvent extraction method, the structure morphology of oil-rich emulsion was still unclear. The current study aimed to investigate the structure morphology of oil-rich emulsion from EAEP using 3D confocal Raman imaging technique. With increasing the enzymatic hydrolysis duration from 1 to 3 h, the stability of oil-rich emulsion was decreased as visualized in the 3D confocal Raman images that the protein and oil were mixed together. The subsequent Raman spectrum analysis further revealed that the decreased stability of oil-rich emulsion was due to the protein aggregations via SS bonds or protein-lipid interactions. The conformational transfer in protein indicated the formation of a compact structure. Copyright © 2017 Elsevier Ltd. All rights reserved.

Confocal microscopy imaging of the biofilm matrix

DEFF Research Database (Denmark)

Schlafer, Sebastian; Meyer, Rikke L

2017-01-01

The extracellular matrix is an integral part of microbial biofilms and an important field of research. Confocal laser scanning microscopy is a valuable tool for the study of biofilms, and in particular of the biofilm matrix, as it allows real-time visualization of fully hydrated, living specimens...... the concentration of solutes and the diffusive properties of the biofilm matrix....

In situ protein expression in tumour spheres: development of an immunostaining protocol for confocal microscopy

International Nuclear Information System (INIS)

Weiswald, Louis-Bastien; Guinebretière, Jean-Marc; Richon, Sophie; Bellet, Dominique; Saubaméa, Bruno; Dangles-Marie, Virginie

2010-01-01

Multicellular tumour sphere models have been shown to closely mimic phenotype characteristics of in vivo solid tumours, or to allow in vitro propagation of cancer stem cells (CSCs). CSCs are usually characterized by the expression of specific membrane markers using flow cytometry (FC) after enzymatic dissociation. Consequently, the spatial location of positive cells within spheres is not documented. Confocal microscopy is the best technique for the imaging of thick biological specimens after multi-labelling but suffers from poor antibody penetration. Thus, we describe here a new protocol for in situ confocal imaging of protein expression in intact spheroids. Protein expression in whole spheroids (150 μm in diameter) from two human colon cancer cell lines, HT29 and CT320X6, has been investigated with confocal immunostaining, then compared with profiles obtained through paraffin immunohistochemistry (pIHC) and FC. Target antigens, relevant for colon cancer and with different expression patterns, have been studied. We first demonstrate that our procedure overcomes the well-known problem of antibody penetration in compact structures by performing immunostaining of EpCAM, a membrane protein expressed by all cells within our spheroids. EpCAM expression is detected in all cells, even the deepest ones. Likewise, antibody access is confirmed with CK20 and CD44 immunostaining. Confocal imaging shows that 100% of cells express β-catenin, mainly present in the plasma membrane with also cytoplasmic and nuclear staining, in agreement with FC and pIHC data. pIHC and confocal imaging show similar CA 19-9 cytoplasmic and membranar expression profile in a cell subpopulation. CA 19-9 + cell count confirms confocal imaging as a highly sensitive method (75%, 62% and 51%, for FC, confocal imaging and pIHC, respectively). Finally, confocal imaging reveals that the weak expression of CD133, a putative colon CSC marker, is restricted to the luminal cell surface of colorectal cancer acini

The Use of Intravital Two-Photon and Thick Section Confocal Imaging to Analyze B Lymphocyte Trafficking in Lymph Nodes and Spleen.

Science.gov (United States)

Park, Chung; Hwang, Il-Young; Kehrl, John H

2018-01-01

Intravital two-photon laser scanning microscopy (TP-LSM) has allowed the direct observation of immune cells in intact organs of living animals. In the B cell biology field TP-LSM has detailed the movement of B cells in high endothelial venules and during their transmigration into lymph organs; described the movement and positioning of B cells within lymphoid organs; outlined the mechanisms by which antigen is delivered to B cells; observed B cell interacting with T cells, other cell types, and even with pathogens; and delineated the egress of B cells from the lymph node (LN) parenchyma into the efferent lymphatics. As the quality of TP-LSM improves and as new fluorescent probes become available additional insights into B cell behavior and function await new investigations. Yet intravital TP-LSM has some disadvantages including a lower resolution than standard confocal microscopy, a narrow imaging window, and a shallow depth of imaging. We have found that supplementing intravital TP-LSM with conventional confocal microscopy using thick LN sections helps to overcome some of these shortcomings. Here, we describe procedures for visualizing the behavior and trafficking of fluorescently labeled, adoptively transferred antigen-activated B cells within the inguinal LN of live mice using two-photon microscopy. Also, we introduce procedures for fixed thick section imaging using standard confocal microscopy, which allows imaging of fluorescently labeled cells deep in the LN cortex and in the spleen with high resolution.

Identification of nodal tissue in the living heart using rapid scanning fiber-optics confocal microscopy and extracellular fluorophores.

Science.gov (United States)

Huang, Chao; Kaza, Aditya K; Hitchcock, Robert W; Sachse, Frank B

2013-09-01

Risks associated with pediatric reconstructive heart surgery include injury of the sinoatrial node (SAN) and atrioventricular node (AVN), requiring cardiac rhythm management using implantable pacemakers. These injuries are the result of difficulties in identifying nodal tissues intraoperatively. Here we describe an approach based on confocal microscopy and extracellular fluorophores to quantify tissue microstructure and identify nodal tissue. Using conventional 3-dimensional confocal microscopy we investigated the microstructural arrangement of SAN, AVN, and atrial working myocardium (AWM) in fixed rat heart. AWM exhibited a regular striated arrangement of the extracellular space. In contrast, SAN and AVN had an irregular, reticulated arrangement. AWM, SAN, and AVN tissues were beneath a thin surface layer of tissue that did not obstruct confocal microscopic imaging. Subsequently, we imaged tissues in living rat hearts with real-time fiber-optics confocal microscopy. Fiber-optics confocal microscopy images resembled images acquired with conventional confocal microscopy. We investigated spatial regularity of tissue microstructure from Fourier analysis and second-order image moments. Fourier analysis of fiber-optics confocal microscopy images showed that the spatial regularity of AWM was greater than that of nodal tissues (37.5 ± 5.0% versus 24.3 ± 3.9% for SAN and 23.8 ± 3.7% for AVN; Pfiber-optics confocal microscopy. Application of the approach in pediatric reconstructive heart surgery may reduce risks of injuring nodal tissues.

Gastric Tissue Damage Analysis Generated by Ischemia: Bioimpedance, Confocal Endomicroscopy, and Light Microscopy

Directory of Open Access Journals (Sweden)

Nohra E. Beltran

2013-01-01

Full Text Available The gastric mucosa ischemic tissular damage plays an important role in critical care patients’ outcome, because it is the first damaged tissue by compensatory mechanism during shock. The aim of the study is to relate bioimpedance changes with tissular damage level generated by ischemia by means of confocal endomicroscopy and light microscopy. Bioimpedance of the gastric mucosa and confocal images were obtained from Wistar male rats during basal and ischemia conditions. They were anesthetized, and stain was applied (fluorescein and/or acriflavine. The impedance spectroscopy catheter was inserted and then confocal endomicroscopy probe. After basal measurements and biopsy, hepatic and gastric arteries clamping induced ischemia. Finally, pyloric antrum tissue was preserved in buffered formaldehyde (10% for histology processing using light microscopy. Confocal images were equalized, binarized, and boundary defined, and infiltrations were quantified. Impedance and infiltrations increased with ischemia showing significant changes between basal and ischemia conditions (. Light microscopy analysis allows detection of general alterations in cellular and tissular integrity, confirming gastric reactance and confocal images quantification increments obtained during ischemia.

Improved axial resolution of FINCH fluorescence microscopy when combined with spinning disk confocal microscopy.

Science.gov (United States)

Siegel, Nisan; Brooker, Gary

2014-09-22

FINCH holographic fluorescence microscopy creates super-resolved images with enhanced depth of focus. Addition of a Nipkow disk real-time confocal image scanner is shown to reduce the FINCH depth of focus while improving transverse confocal resolution in a combined method called "CINCH".

Nano-displacement measurement based on virtual pinhole confocal method

International Nuclear Information System (INIS)

Li, Long; Kuang, Cuifang; Xue, Yi; Liu, Xu

2013-01-01

A virtual pinhole confocal system based on charge-coupled device (CCD) detection and image processing techniques is built to measure axial displacement with 10 nm resolution, preeminent flexibility and excellent robustness when facing spot drifting. Axial displacement of the sample surface is determined by capturing the confocal laser spot using a CCD detector and quantifying the energy collected by programmable virtual pinholes. Experiments indicate an applicable measuring range of 1000 nm (Gaussian fitting r = 0.9902) with a highly linear range of 500 nm (linear fitting r = 0.9993). A concentric subtraction algorithm is introduced to further enhance resolution. Factors affecting measuring precision, sensitivity and signal-to-noise ratio are discussed using theoretical deductions and diffraction simulations. The virtual pinhole technique has promising applications in surface profiling and confocal imaging applications which require easily-customizable pinhole configurations. (paper)

Electrophoretic Detection and Confocal Microscopic Imaging of Tyrosine Nitrated Proteins in Plant Tissue.

Science.gov (United States)

Arora, Dhara; Singh, Neha; Bhatla, Satish C

2018-01-01

Tyrosine nitrated proteins can be detected in plant cells electrophoretically and their distribution can be monitored by confocal laser scanning microscopy (CLSM) imaging. One-dimensional polyacrylamide gel electrophoresis (1D PAGE) followed by Western blotting using polyclonal antibody against 3-nitrotyrosine residues enables detection of tyrosine nitrated proteins in plant cells. Here we describe detection of tyrosine nitrated proteins in the homogenates derived from sunflower (Helianthus annuus L.) seedling cotyledons. Total soluble proteins obtained from tissue homogenates are resolved using vertical gel electrophoresis followed by their electrophoretic transfer on to a microporous membrane support for immunodetection. Spatial distribution of tyrosine nitrated proteins can be visualized using an antibody against 3-nitrotyrosine residues. Immunofluorescent localization is performed by cutting 7 μm thick wax sections of tissue followed by incubation in primary anti-nitrotyrosine antibody (dilution 1:200) and secondary Cy-3 labeled anti-rabbit IgG antibody (dilution 1:1500). Confocal laser scanning microscopy analysis is undertaken using argon lasers (ex: 530-550 nm and em: 570 nm) at pinhole 1. Modulation in the abundance and spatial localization of tyrosine nitrated proteins in plant tissues can be monitored using these techniques.

Confocal Microscopy

Science.gov (United States)

Liu, Jian; Tan, Jiubin

2016-12-01

The confocal microscope is appropriate for imaging cells or the measurement of industrial artefacts. However, junior researchers and instrument users sometimes misuse imaging concepts and metrological characteristics, such as position resolution in industrial metrology and scale resolution in bio-imaging. And, metrological characteristics or influence factors in 3D measurement such as height assessment error caused by 3D coupling effect are so far not yet identified. In this book, the authors outline their practices by the working experiences on standardization and system design. This book assumes little previous knowledge of optics, but rich experience in engineering of industrial measurements, in particular with profile metrology or areal surface topography will be very helpful to understand the theoretical concerns and value of the technological advances. It should be useful for graduate students or researchers as extended reading material, as well as microscope users alongside their handbook.

DMSP SSM/I- Microwave Imager

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The SSM/I is a seven-channel, four frequency, linearly-polarized, passive microwave radiometric system which measures atmospheric, ocean and terrain microwave...

Statistical region based active contour using a fractional entropy descriptor: Application to nuclei cell segmentation in confocal \\ud microscopy images

OpenAIRE

Histace, A; Meziou, B J; Matuszewski, Bogdan; Precioso, F; Murphy, M F; Carreiras, F

2013-01-01

We propose an unsupervised statistical region based active contour approach integrating an original fractional entropy measure for image segmentation with a particular application to single channel actin tagged fluorescence confocal microscopy image segmentation. Following description of statistical based active contour segmentation and the mathematical definition of the proposed fractional entropy descriptor, we demonstrate comparative segmentation results between the proposed approach and s...

Spectral confocal reflection microscopy using a white light source

Science.gov (United States)

Booth, M.; Juškaitis, R.; Wilson, T.

2008-08-01

We present a reflection confocal microscope incorporating a white light supercontinuum source and spectral detection. The microscope provides images resolved spatially in three-dimensions, in addition to spectral resolution covering the wavelength range 450-650nm. Images and reflection spectra of artificial and natural specimens are presented, showing features that are not normally revealed in conventional microscopes or confocal microscopes using discrete line lasers. The specimens include thin film structures on semiconductor chips, iridescent structures in Papilio blumei butterfly scales, nacre from abalone shells and opal gemstones. Quantitative size and refractive index measurements of transparent beads are derived from spectral interference bands.

Synthetic Microwave Imaging Reflectometry diagnostic using 3D FDTD Simulations

Science.gov (United States)

Kruger, Scott; Jenkins, Thomas; Smithe, David; King, Jacob; Nimrod Team Team

2017-10-01

Microwave Imaging Reflectometry (MIR) has become a standard diagnostic for understanding tokamak edge perturbations, including the edge harmonic oscillations in QH mode operation. These long-wavelength perturbations are larger than the normal turbulent fluctuation levels and thus normal analysis of synthetic signals become more difficult. To investigate, we construct a synthetic MIR diagnostic for exploring density fluctuation amplitudes in the tokamak plasma edge by using the three-dimensional, full-wave FDTD code Vorpal. The source microwave beam for the diagnostic is generated and refelected at the cutoff surface that is distorted by 2D density fluctuations in the edge plasma. Synthetic imaging optics at the detector can be used to understand the fluctuation and background density profiles. We apply the diagnostic to understand the fluctuations in edge plasma density during QH-mode activity in the DIII-D tokamak, as modeled by the NIMROD code. This work was funded under DOE Grant Number DE-FC02-08ER54972.

Sensitive elemental detection using microwave-assisted laser-induced breakdown imaging

Science.gov (United States)

Iqbal, Adeel; Sun, Zhiwei; Wall, Matthew; Alwahabi, Zeyad T.

2017-10-01

This study reports a sensitive spectroscopic method for quantitative elemental detection by manipulating the temporal and spatial parameters of laser-induced plasma. The method was tested for indium detection in solid samples, in which laser ablation was used to generate a tiny plasma. The lifetime of the laser-induced plasma can be extended to hundreds of microseconds using microwave injection to remobilize the electrons. In this novel method, temporal integrated signal of indium emission was significantly enhanced. Meanwhile, the projected detectable area of the excited indium atoms was also significantly improved using an interference-, instead of diffraction-, based technique, achieved by directly imaging microwave-enhanced plasma through a novel narrow-bandpass filter, exactly centered at the indium emission line. Quantitative laser-induce breakdown spectroscopy was also recorded simultaneously with the new imaging method. The intensities recorded from both methods exhibit very good mutual linear relationship. The detection intensity was improved to 14-folds because of the combined improvements in the plasma lifetime and the area of detection.

CINCH (confocal incoherent correlation holography) super resolution fluorescence microscopy based upon FINCH (Fresnel incoherent correlation holography).

Science.gov (United States)

Siegel, Nisan; Storrie, Brian; Bruce, Marc; Brooker, Gary

2015-02-07

FINCH holographic fluorescence microscopy creates high resolution super-resolved images with enhanced depth of focus. The simple addition of a real-time Nipkow disk confocal image scanner in a conjugate plane of this incoherent holographic system is shown to reduce the depth of focus, and the combination of both techniques provides a simple way to enhance the axial resolution of FINCH in a combined method called "CINCH". An important feature of the combined system allows for the simultaneous real-time image capture of widefield and holographic images or confocal and confocal holographic images for ready comparison of each method on the exact same field of view. Additional GPU based complex deconvolution processing of the images further enhances resolution.

A Simple Model for Nonlinear Confocal Ultrasonic Beams

Science.gov (United States)

Zhang, Dong; Zhou, Lin; Si, Li-Sheng; Gong, Xiu-Fen

2007-01-01

A confocally and coaxially arranged pair of focused transmitter and receiver represents one of the best geometries for medical ultrasonic imaging and non-invasive detection. We develop a simple theoretical model for describing the nonlinear propagation of a confocal ultrasonic beam in biological tissues. On the basis of the parabolic approximation and quasi-linear approximation, the nonlinear Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation is solved by using the angular spectrum approach. Gaussian superposition technique is applied to simplify the solution, and an analytical solution for the second harmonics in the confocal ultrasonic beam is presented. Measurements are performed to examine the validity of the theoretical model. This model provides a preliminary model for acoustic nonlinear microscopy.

Model wavefront sensor for adaptive confocal microscopy

Science.gov (United States)

Booth, Martin J.; Neil, Mark A. A.; Wilson, Tony

2000-05-01

A confocal microscope permits 3D imaging of volume objects by the inclusion of a pinhole in the detector path which eliminates out of focus light. This configuration is however very sensitive to aberrations induced by the specimen or the optical system and would therefore benefit from an adaptive optics approach. We present a wavefront sensor capable of measuring directly the Zernike components of an aberrated wavefront and show that it is particularly applicable to the confocal microscope since only those wavefronts originating in the focal region contribute to the measured aberration.

GPU accelerated real-time confocal fluorescence lifetime imaging microscopy (FLIM) based on the analog mean-delay (AMD) method

Science.gov (United States)

Kim, Byungyeon; Park, Byungjun; Lee, Seungrag; Won, Youngjae

2016-01-01

We demonstrated GPU accelerated real-time confocal fluorescence lifetime imaging microscopy (FLIM) based on the analog mean-delay (AMD) method. Our algorithm was verified for various fluorescence lifetimes and photon numbers. The GPU processing time was faster than the physical scanning time for images up to 800 × 800, and more than 149 times faster than a single core CPU. The frame rate of our system was demonstrated to be 13 fps for a 200 × 200 pixel image when observing maize vascular tissue. This system can be utilized for observing dynamic biological reactions, medical diagnosis, and real-time industrial inspection. PMID:28018724

Scattering features for lung cancer detection in fibered confocal fluorescence microscopy images.

Science.gov (United States)

Rakotomamonjy, Alain; Petitjean, Caroline; Salaün, Mathieu; Thiberville, Luc

2014-06-01

To assess the feasibility of lung cancer diagnosis using fibered confocal fluorescence microscopy (FCFM) imaging technique and scattering features for pattern recognition. FCFM imaging technique is a new medical imaging technique for which interest has yet to be established for diagnosis. This paper addresses the problem of lung cancer detection using FCFM images and, as a first contribution, assesses the feasibility of computer-aided diagnosis through these images. Towards this aim, we have built a pattern recognition scheme which involves a feature extraction stage and a classification stage. The second contribution relies on the features used for discrimination. Indeed, we have employed the so-called scattering transform for extracting discriminative features, which are robust to small deformations in the images. We have also compared and combined these features with classical yet powerful features like local binary patterns (LBP) and their variants denoted as local quinary patterns (LQP). We show that scattering features yielded to better recognition performances than classical features like LBP and their LQP variants for the FCFM image classification problems. Another finding is that LBP-based and scattering-based features provide complementary discriminative information and, in some situations, we empirically establish that performance can be improved when jointly using LBP, LQP and scattering features. In this work we analyze the joint capability of FCFM images and scattering features for lung cancer diagnosis. The proposed method achieves a good recognition rate for such a diagnosis problem. It also performs well when used in conjunction with other features for other classical medical imaging classification problems. Copyright © 2014 Elsevier B.V. All rights reserved.

A statistical pixel intensity model for segmentation of confocal laser scanning microscopy images.

Science.gov (United States)

Calapez, Alexandre; Rosa, Agostinho

2010-09-01

Confocal laser scanning microscopy (CLSM) has been widely used in the life sciences for the characterization of cell processes because it allows the recording of the distribution of fluorescence-tagged macromolecules on a section of the living cell. It is in fact the cornerstone of many molecular transport and interaction quantification techniques where the identification of regions of interest through image segmentation is usually a required step. In many situations, because of the complexity of the recorded cellular structures or because of the amounts of data involved, image segmentation either is too difficult or inefficient to be done by hand and automated segmentation procedures have to be considered. Given the nature of CLSM images, statistical segmentation methodologies appear as natural candidates. In this work we propose a model to be used for statistical unsupervised CLSM image segmentation. The model is derived from the CLSM image formation mechanics and its performance is compared to the existing alternatives. Results show that it provides a much better description of the data on classes characterized by their mean intensity, making it suitable not only for segmentation methodologies with known number of classes but also for use with schemes aiming at the estimation of the number of classes through the application of cluster selection criteria.

Adapting a compact confocal microscope system to a two-photon excitation fluorescence imaging architecture.

Science.gov (United States)

Diaspro, A; Corosu, M; Ramoino, P; Robello, M

1999-11-01

Within the framework of a national National Institute of Physics of Matter (INFM) project, we have realised a two-photon excitation (TPE) fluorescence microscope based on a new generation commercial confocal scanning head. The core of the architecture is a mode-locked Ti:Sapphire laser (Tsunami 3960, Spectra Physics Inc., Mountain View, CA) pumped by a high-power (5 W, 532 nm) laser (Millennia V, Spectra Physics Inc.) and an ultracompact confocal scanning head, Nikon PCM2000 (Nikon Instruments, Florence, Italy) using a single-pinhole design. Three-dimensional point-spread function has been measured to define spatial resolution performances. The TPE microscope has been used with a wide range of excitable fluorescent molecules (DAPI, Fura-2, Indo-1, DiOC(6)(3), fluoresceine, Texas red) covering a single photon spectral range from UV to green. An example is reported on 3D imaging of the helical structure of the sperm head of the Octopus Eledone cirrhosa labelled with an UV excitable dye, i.e., DAPI. The system can be easily switched for operating both in conventional and two-photon mode. Copyright 1999 Wiley-Liss, Inc.

Simulation of Optical and Synthetic Imaging using Microwave Reflectometry

International Nuclear Information System (INIS)

Kramer, G.J.; Nazikian, R.; Valeo, E.

2004-01-01

Two-dimensional full-wave time-dependent simulations in full plasma geometry are presented which show that conventional reflectometry (without a lens) can be used to synthetically image density fluctuations in fusion plasmas under conditions where the parallel correlation length greatly exceeds the poloidal correlation length of the turbulence. The advantage of synthetic imaging is that the image can be produced without the need for a large lens of high optical quality, and each frequency that is launched can be independently imaged. A particularly simple arrangement, consisting of a single receiver located at the midpoint of a microwave beam propagating along the plasma midplane is shown to suffice for imaging purposes. However, as the ratio of the parallel to poloidal correlation length decreases, a poloidal array of receivers needs to be used to synthesize the image with high accuracy. Simulations using DIII-D relevant parameters show the similarity of synthetic and optical imaging in present-day experiments

Simulation of Optical and Synthetic Imaging using Microwave Reflectometry

Energy Technology Data Exchange (ETDEWEB)

G.J. Kramer; R. Nazikian; E. Valeo

2004-01-16

Two-dimensional full-wave time-dependent simulations in full plasma geometry are presented which show that conventional reflectometry (without a lens) can be used to synthetically image density fluctuations in fusion plasmas under conditions where the parallel correlation length greatly exceeds the poloidal correlation length of the turbulence. The advantage of synthetic imaging is that the image can be produced without the need for a large lens of high optical quality, and each frequency that is launched can be independently imaged. A particularly simple arrangement, consisting of a single receiver located at the midpoint of a microwave beam propagating along the plasma midplane is shown to suffice for imaging purposes. However, as the ratio of the parallel to poloidal correlation length decreases, a poloidal array of receivers needs to be used to synthesize the image with high accuracy. Simulations using DIII-D relevant parameters show the similarity of synthetic and optical imaging in present-day experiments.

Interfacing 3D magnetic twisting cytometry with confocal fluorescence microscopy to image force responses in living cells.

Science.gov (United States)

Zhang, Yuejin; Wei, Fuxiang; Poh, Yeh-Chuin; Jia, Qiong; Chen, Junjian; Chen, Junwei; Luo, Junyu; Yao, Wenting; Zhou, Wenwen; Huang, Wei; Yang, Fang; Zhang, Yao; Wang, Ning

2017-07-01

Cells and tissues can undergo a variety of biological and structural changes in response to mechanical forces. Only a few existing techniques are available for quantification of structural changes at high resolution in response to forces applied along different directions. 3D-magnetic twisting cytometry (3D-MTC) is a technique for applying local mechanical stresses to living cells. Here we describe a protocol for interfacing 3D-MTC with confocal fluorescence microscopy. In 3D-MTC, ferromagnetic beads are bound to the cell surface via surface receptors, followed by their magnetization in any desired direction. A magnetic twisting field in a different direction is then applied to generate rotational shear stresses in any desired direction. This protocol describes how to combine magnetic-field-induced mechanical stimulation with confocal fluorescence microscopy and provides an optional extension for super-resolution imaging using stimulated emission depletion (STED) nanoscopy. This technology allows for rapid real-time acquisition of a living cell's mechanical responses to forces via specific receptors and for quantifying structural and biochemical changes in the same cell using confocal fluorescence microscopy or STED. The integrated 3D-MTC-microscopy platform takes ∼20 d to construct, and the experimental procedures require ∼4 d when carried out by a life sciences graduate student.

Confocal Microscopy of Unfixed Breast Needle Core Biopsies: A Comparison to Fixed and Stained Sections

Directory of Open Access Journals (Sweden)

Zavislan James M

2009-08-01

Full Text Available Abstract Background Needle core biopsy, often in conjunction with ultrasonic or stereotactic guided techniques, is frequently used to diagnose breast carcinoma in women. Confocal scanning laser microscopy (CSLM is a technology that provides real-time digital images of tissues with cellular resolution. This paper reports the progress in developing techniques to rapidly screen needle core breast biopsy and surgical specimens at the point of care. CSLM requires minimal tissue processing and has the potential to reduce the time from excision to diagnosis. Following imaging, specimens can still be submitted for standard histopathological preparation. Methods Needle core breast specimens from 49 patients were imaged at the time of biopsy. These lesions had been characterized under the Breast Imaging Reporting And Data System (BI-RADS as category 3, 4 or 5. The core biopsies were imaged with the CSLM before fixation. Samples were treated with 5% citric acid and glycerin USP to enhance nuclear visibility in the reflectance confocal images. Immediately following imaging, the specimens were fixed in buffered formalin and submitted for histological processing and pathological diagnosis. CSLM images were then compared to the standard histology. Results The pathologic diagnoses by standard histology were 7 invasive ductal carcinomas, 2 invasive lobular carcinomas, 3 ductal carcinomas in-situ (CIS, 21 fibrocystic changes/proliferative conditions, 9 fibroadenomas, and 5 other/benign; two were excluded due to imaging difficulties. Morphologic and cellular features of benign and cancerous lesions were identified in the confocal images and were comparable to standard histologic sections of the same tissue. Conclusion CSLM is a technique with the potential to screen needle core biopsy specimens in real-time. The confocal images contained sufficient information to identify stromal reactions such as fibrosis and cellular proliferations such as intra-ductal and

Confocal Microscopy of Unfixed Breast Needle Core Biopsies: A Comparison to Fixed and Stained Sections

Science.gov (United States)

2009-01-01

Background Needle core biopsy, often in conjunction with ultrasonic or stereotactic guided techniques, is frequently used to diagnose breast carcinoma in women. Confocal scanning laser microscopy (CSLM) is a technology that provides real-time digital images of tissues with cellular resolution. This paper reports the progress in developing techniques to rapidly screen needle core breast biopsy and surgical specimens at the point of care. CSLM requires minimal tissue processing and has the potential to reduce the time from excision to diagnosis. Following imaging, specimens can still be submitted for standard histopathological preparation. Methods Needle core breast specimens from 49 patients were imaged at the time of biopsy. These lesions had been characterized under the Breast Imaging Reporting And Data System (BI-RADS) as category 3, 4 or 5. The core biopsies were imaged with the CSLM before fixation. Samples were treated with 5% citric acid and glycerin USP to enhance nuclear visibility in the reflectance confocal images. Immediately following imaging, the specimens were fixed in buffered formalin and submitted for histological processing and pathological diagnosis. CSLM images were then compared to the standard histology. Results The pathologic diagnoses by standard histology were 7 invasive ductal carcinomas, 2 invasive lobular carcinomas, 3 ductal carcinomas in-situ (CIS), 21 fibrocystic changes/proliferative conditions, 9 fibroadenomas, and 5 other/benign; two were excluded due to imaging difficulties. Morphologic and cellular features of benign and cancerous lesions were identified in the confocal images and were comparable to standard histologic sections of the same tissue. Conclusion CSLM is a technique with the potential to screen needle core biopsy specimens in real-time. The confocal images contained sufficient information to identify stromal reactions such as fibrosis and cellular proliferations such as intra-ductal and infiltrating carcinoma, and

Microwave tomography for functional imaging of extremity soft tissues: feasibility assessment

International Nuclear Information System (INIS)

Semenov, Serguei; Kellam, James; Althausen, Peter; Williams, Thomas; Abubakar, Aria; Bulyshev, Alexander; Sizov, Yuri

2007-01-01

It is important to assess the viability of extremity soft tissues, as this component is often the determinant of the final outcome of fracture treatment. Microwave tomography (MWT) and sensing might be able to provide a fast and mobile assessment of such properties. MWT imaging of extremities possesses a complicated, nonlinear, high dielectric contrast inverse problem of diffraction tomography. There is a high dielectric contrast between bone and soft tissue in the extremities. A contrast between soft tissue abnormalities is less pronounced when compared with the high bone-soft tissue contrast. The goal of this study was to assess the feasibility of MWT for functional imaging of extremity soft tissues, i.e. to detect a relatively small contrast within soft tissues in closer proximity to high contrast boney areas. Both experimental studies and computer simulation were performed. Experiments were conducted using live pigs with compromised blood flow and compartment syndrome within an extremity. A whole 2D tomographic imaging cycle at 1 GHz was computer simulated and images were reconstructed using the Newton, MR-CSI and modified Born methods. Results of experimental studies demonstrate that microwave technology is sensitive to changes in the soft tissue blood content and elevated compartment pressure. It was demonstrated that MWT is feasible for functional imaging of extremity soft tissues, circulatory-related changes, blood flow and elevated compartment pressure

Confocal microscopy for astrocyte in vivo imaging: Recycle and reuse in microscopy

Science.gov (United States)

Pérez-Alvarez, Alberto; Araque, Alfonso; Martín, Eduardo D.

2013-01-01

In vivo imaging is one of the ultimate and fundamental approaches for the study of the brain. Two-photon laser scanning microscopy (2PLSM) constitutes the state-of-the-art technique in current neuroscience to address questions regarding brain cell structure, development and function, blood flow regulation and metabolism. This technique evolved from laser scanning confocal microscopy (LSCM), which impacted the field with a major improvement in image resolution of live tissues in the 1980s compared to widefield microscopy. While nowadays some of the unparalleled features of 2PLSM make it the tool of choice for brain studies in vivo, such as the possibility to image deep within a tissue, LSCM can still be useful in this matter. Here we discuss the validity and limitations of LSCM and provide a guide to perform high-resolution in vivo imaging of the brain of live rodents with minimal mechanical disruption employing LSCM. We describe the surgical procedure and experimental setup that allowed us to record intracellular calcium variations in astrocytes evoked by sensory stimulation, and to monitor intact neuronal dendritic spines and astrocytic processes as well as blood vessel dynamics. Therefore, in spite of certain limitations that need to be carefully considered, LSCM constitutes a useful, convenient, and affordable tool for brain studies in vivo. PMID:23658537

Hybrid Rayleigh, Raman and TPE fluorescence spectral confocal microscopy of living cells

NARCIS (Netherlands)

Pully, V.V.; Lenferink, Aufrid T.M.; Otto, Cornelis

2010-01-01

A hybrid fluorescence–Raman confocal microscopy platform is presented, which integrates low-wavenumber-resolution Raman imaging, Rayleigh scatter imaging and two-photon fluorescence (TPE) spectral imaging, fast ‘amplitude-only’ TPE-fluorescence imaging and high-spectral-resolution Raman imaging.

Confocal Microscope Alignment of Nanocrystals for Coherent Diffraction Imaging

International Nuclear Information System (INIS)

Beitra, Loren; Watari, Moyu; Matsuura, Takashi; Shimamoto, Naonobu; Harder, Ross; Robinson, Ian

2010-01-01

We have installed and tested an Olympus LEXT confocal microscope at the 34-ID-C beamline of the Advanced Photon Source (APS). The beamline is for Coherent X-ray Diffraction (CXD) experiments in which a nanometre-sized crystal is aligned inside a focussed X-ray beam. The microscope was required for three-dimensional (3D) sample alignment to get around sphere-of-confusion issues when locating Bragg peaks in reciprocal space. In this way, and by use of strategic sample preparations, we have succeeded in measuring six Bragg peaks from a single 200 nm gold crystal and obtained six projections of its internal displacement field. This enables the clear identification of stacking-fault bands within the crystal. The confocal alignment method will allow a full determination of the strain tensor provided three or more Bragg reflections from the same crystal are found.

Microwave tomography of extremities: 2. Functional fused imaging of flow reduction and simulated compartment syndrome

International Nuclear Information System (INIS)

Semenov, Serguei; Nair, Bindu; Kellam, James; Williams, Thomas; Quinn, Michael; Sizov, Yuri; Nazarov, Alexei; Pavlovsky, Andrey

2011-01-01

Medical imaging has recently expanded into the dual- or multi-modality fusion of anatomical and functional imaging modalities. This significantly improves the diagnostic power while simultaneously increasing the cost of already expensive medical devices or investigations and decreasing their mobility. We are introducing a novel imaging concept of four-dimensional (4D) microwave tomographic (MWT) functional imaging: three dimensional (3D) in the spatial domain plus one dimensional (1D) in the time, functional dynamic domain. Instead of a fusion of images obtained by different imaging modalities, 4D MWT fuses absolute anatomical images with dynamic, differential images of the same imaging technology. The approach was successively validated in animal experiments with short-term arterial flow reduction and a simulated compartment syndrome in an initial simplified experimental setting using a dedicated MWT system. The presented fused images are not perfect as MWT is a novel imaging modality at its early stage of the development and ways of reading reconstructed MWT images need to be further studied and understood. However, the reconstructed fused images present clear evidence that microwave tomography is an emerging imaging modality with great potentials for functional imaging.

Microwave impedance imaging on semiconductor memory devices

Science.gov (United States)

Kundhikanjana, Worasom; Lai, Keji; Yang, Yongliang; Kelly, Michael; Shen, Zhi-Xun

2011-03-01

Microwave impedance microscopy (MIM) maps out the real and imaginary components of the tip-sample impedance, from which the local conductivity and dielectric constant distribution can be derived. The stray field contribution is minimized in our shielded cantilever design, enabling quantitative analysis of nano-materials and device structures. We demonstrate here that the MIM can spatially resolve the conductivity variation in a dynamic random access memory (DRAM) sample. With DC or low-frequency AC bias applied to the tip, contrast between n-doped and p-doped regions in the dC/dV images is observed, and p-n junctions are highlighted in the dR/dV images. The results can be directly compared with data taken by scanning capacitance microscope (SCM), which uses unshielded cantilevers and resonant electronics, and the MIM reveals more information of the local dopant concentration than SCM.

Imaging phospholipid conformational disorder and packing in giant multilamellar liposome by confocal Raman microspectroscopy

Science.gov (United States)

Noothalapati, Hemanth; Iwasaki, Keita; Yoshimoto, Chikako; Yoshikiyo, Keisuke; Nishikawa, Tomoe; Ando, Masahiro; Hamaguchi, Hiro-o.; Yamamoto, Tatsuyuki

2017-12-01

Liposomes are closed phospholipid bilayer systems that have profound applications in fundamental cell biology, pharmaceutics and medicine. Depending on the composition (pure or mixture of phospholipids, presence of cholesterol) and preparation protocol, intra- and inter-chain molecular interactions vary leading to changes in the quality (order and packing) of liposomes. So far it is not possible to image conformational disorders and packing densities within a liposome in a straightforward manner. In this study, we utilized confocal Raman microspectroscopy to visualize structural disorders and packing efficiency within a giant multilamellar liposome model by focusing mainly on three regions in the vibrational spectrum (Csbnd C stretching, Csbnd H deformation and Csbnd H stretching). We estimated properties such as trans/gauche isomers and lateral packing probability. Interestingly, our Raman imaging studies revealed gel phase rich domains and heterogeneous lateral packing within the giant multilamellar liposome.

Confocal Microscopy and Image Analysis Indicates a Region-Specific Relation between Active Caspases and Cytoplasm in Ejaculated and Epididymal Sperm

Science.gov (United States)

García Vazquez, Susana; Aragón Martínez, Andrés; Flores-Alonso, Juan Carlos

2012-01-01

Previously, it was suggested a relation between the presence of apoptosis markers with cytoplasm in mammalian sperm. In this work, flow cytometry, confocal microscopy and image analysis were used to analyze the relationship between active caspase-3 and -7 and intracellular esterases expression in ejaculated or epididymal ram sperm. Sperm obtained from ejaculates from the caput, corpus, or cauda of the epididymis were treated with an inhibitor of active caspase-3 and -7 and a marker of cytoplasmic esterases. Additionally, ejaculated sperm were incubated for one, two, or three hours before evaluation for active caspases. Sperm subpopulations positive for active caspases and/or intracellular esterases were detected by flow cytometry and confocal microscopy; however, image analysis of confocal images showed that the correlation between active caspases and cytoplasmic esterases in sperm is region-specific. Lower values of Spearman correlation coefficients were found when whole sperm or head sperm was analyzed; however, a high correlation was observed for midpiece sperm. Incubation of sperm for two or three hours promoted the autoactivation of caspases. It has been suggested that the presence of apoptotic markers in sperm are related with a process of abortive apoptosis and with errors during spermiogenesis. Our results permit us suggest that the origin of the relationship between active caspases and cytoplasmic esterases is due to differentiation errors occurring during spermiogenesis because the percentages of sperm with active caspases are not different in the caput, corpus, or cauda of the epididymis. In this study we demonstrate that existing sperm subpopulations can express active caspases and intracellular esterases and that the correlation between these molecules is high in midpiece sperm. PMID:22530029

Optomechatronics Design and Control for Confocal Laser Scanning Microscopy

NARCIS (Netherlands)

Yoo, H.W.

2015-01-01

Confocal laser scanning microscopy (CLSM) is considered as one of the major advancements in microscopy in the last century and is widely accepted as a 3D fluorescence imaging tool for biological studies. For the emerging biological questions CLSM requires fast imaging to detect rapid biological

Synthetic Aperture Microwave Imaging (SAMI) of the plasma edge on NSTX-U

Science.gov (United States)

Vann, Roddy; Taylor, Gary; Brunner, Jakob; Ellis, Bob; Thomas, David

2016-10-01

The Synthetic Aperture Microwave Imaging (SAMI) system is a unique phased-array microwave camera with a +/-40° field of view in both directions. It can image cut-off surfaces corresponding to frequencies in the range 10-34.5GHz; these surfaces are typically in the plasma edge. SAMI operates in two modes: either imaging thermal emission from the plasma (often modified by its interaction with the plasma edge e.g. via BXO mode conversion) or ``active probing'' i.e. injecting a broad beam at the plasma surface and imaging the reflected/back-scattered signal. SAMI was successfully pioneered on the Mega-Amp Spherical Tokamak (MAST) at Culham Centre for Fusion Energy. SAMI has now been installed and commissioned on the National Spherical Torus Experiment Upgrade (NSTX-U) at Princeton Plasma Physics Laboratory. The firmware has been upgraded to include real-time digital filtering, which enables continuous acquisition of the Doppler back-scattered active probing data. In this poster we shall present SAMI's analysis of the plasma edge on NSTX-U including measurements of the edge pitch angle on NSTX-U using SAMI's unique 2-D Doppler-backscattering capability.

EUS-Guided Needle-Based Confocal Laser Endomicroscopy

DEFF Research Database (Denmark)

Bhutani, Manoop S; Koduru, Pramoda; Joshi, Virendra

2015-01-01

Endoscopic ultrasound (EUS) has emerged as an excellent tool for imaging the gastrointestinal tract, as well as surrounding structures. EUS-guided fine-needle aspiration (EUS-FNA) has become the standard of care for the tissue sampling of a variety of masses and lymph nodes within and around...... the gut, providing further diagnostic and staging information. Confocal laser endomicroscopy (CLE) is a novel endoscopic method that enables imaging at a subcellular level of resolution during endoscopy, allowing up to 1000-fold magnification of tissue and providing an optical biopsy. A new procedure...... that has been developed in the past few years is needle-based confocal laser endomicroscopy (nCLE), which involves a mini-CLE probe that can be passed through a 1 9-gauge needle during EUS-FNA. This enables the real-time visualization of tissue at a microscopic level, with the potential to further improve...

Evaluation of the imaging properties of Microwave Imaging Reflectometry

International Nuclear Information System (INIS)

Hong, I; Lee, W; Leem, J; Nam, Y; Kim, M; Yun, G S; Park, H K; Domier, C W; Jr, N C Luhmann

2012-01-01

Microwave Imaging Reflectometry (MIR) has been developed for unambiguous measurement of electron density fluctuations in fusion plasmas. The loss of phase information limiting the use of conventional reflectometry can be minimized by a large aperture imaging optics and an array of detectors in the MIR embodiment. The evaluation of the optical system is critical for precise reconstruction of the fluctuations. The optical systems of the prototype TEXTOR MIR [2] and newly-designed KSTAR MIR [5] systems have been tested with a corrugated target simulating density fluctuations at the cut-off surface. The reconstructed phase from the MIR system has been compared to the directly measured phase of corrugations taking into account the rotational speed of the target. The effects of optical aberrations and interference between lenses on the phase reconstruction have been investigated by the 2D amplitude measurement of the reflected waves and the diffraction-based optical simulations. (CODE V) A preliminary design of the KSTAR MIR optics has been suggested which can minimize the aberration and interference effects.

WE-FG-BRA-04: A Portable Confocal Microscope to Image Live Cell Damage Response Induced by Therapeutic Radiation

Energy Technology Data Exchange (ETDEWEB)

McFadden, C; Flint, D; Grosshans, D; Sawakuchi, G [The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Sadetaporn, D [The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Rice University, Houston, TX (United States); Asaithamby, A [UT Southwestern Medical Center, Dallas, TX (United States)

2016-06-15

Purpose: To construct a custom and portable fluorescence confocal laser-scanning microscope (FCLSM) that can be placed in the path of therapeutic radiation beams to study real-time radiation-induced damage response in live cells. Methods: We designed and constructed a portable FCLSM with three laser diodes for excitation (405, 488, and 635 nm). An objective lens focuses the excitation light and collects fluorescence from the sample. A pair of galvanometer mirrors scans/collects the laser beam/fluorescence along the focal plane (x/y-directions). A stepper motor stage scans in the axial direction and positions the x/y of the image field. Barrier filters and dichroic mirrors are used to route the spectral emission bands to the appropriate photodetector. An avalanche photodiode collects near-infrared fluorescence; a photodiode collects back-reflected 635 nm light; and a photomultiplier tube collects green fluorescence in the range of eGFP/eYFP. A 200-µm diameter pinhole was used to implement the confocal geometry for near-infrared and red channels and a 150-µm diameter pinhole for the green channel. Data acquisition and system control were achieved using a high-throughput data acquisition card. In-house software developed in LabVIEW was used to control the hardware, collect data from the photodetectors and reconstruct the confocal images. Results: 6 frames/s can be acquired for a 25 µm{sup 2} (128×128 pixels) field of view, visualizing the entire volume of the cell nucleus (∼10 µm depth) in <10 s. To demonstrate the usefulness of our FCLSM, we imaged gold nanoshells in live cells, radiation-induced damage in fibrosarcoma cells expressing eGFP tagged to a DNA repair protein, and neurons expressing eGFP. The system can also image particle tracks in fluorescent nuclear track detectors. Conclusion: We developed a versatile and portable FCLSM that allows radiobiology studies in live cells exposed to therapeutic radiation. The FCLSM can be placed in any vertical beam

WE-FG-BRA-04: A Portable Confocal Microscope to Image Live Cell Damage Response Induced by Therapeutic Radiation

International Nuclear Information System (INIS)

McFadden, C; Flint, D; Grosshans, D; Sawakuchi, G; Sadetaporn, D; Asaithamby, A

2016-01-01

Purpose: To construct a custom and portable fluorescence confocal laser-scanning microscope (FCLSM) that can be placed in the path of therapeutic radiation beams to study real-time radiation-induced damage response in live cells. Methods: We designed and constructed a portable FCLSM with three laser diodes for excitation (405, 488, and 635 nm). An objective lens focuses the excitation light and collects fluorescence from the sample. A pair of galvanometer mirrors scans/collects the laser beam/fluorescence along the focal plane (x/y-directions). A stepper motor stage scans in the axial direction and positions the x/y of the image field. Barrier filters and dichroic mirrors are used to route the spectral emission bands to the appropriate photodetector. An avalanche photodiode collects near-infrared fluorescence; a photodiode collects back-reflected 635 nm light; and a photomultiplier tube collects green fluorescence in the range of eGFP/eYFP. A 200-µm diameter pinhole was used to implement the confocal geometry for near-infrared and red channels and a 150-µm diameter pinhole for the green channel. Data acquisition and system control were achieved using a high-throughput data acquisition card. In-house software developed in LabVIEW was used to control the hardware, collect data from the photodetectors and reconstruct the confocal images. Results: 6 frames/s can be acquired for a 25 µm 2 (128×128 pixels) field of view, visualizing the entire volume of the cell nucleus (∼10 µm depth) in <10 s. To demonstrate the usefulness of our FCLSM, we imaged gold nanoshells in live cells, radiation-induced damage in fibrosarcoma cells expressing eGFP tagged to a DNA repair protein, and neurons expressing eGFP. The system can also image particle tracks in fluorescent nuclear track detectors. Conclusion: We developed a versatile and portable FCLSM that allows radiobiology studies in live cells exposed to therapeutic radiation. The FCLSM can be placed in any vertical beam line

Nonlinear Image Restoration in Confocal Microscopy : Stability under Noise

NARCIS (Netherlands)

Roerdink, J.B.T.M.

1995-01-01

In this paper we study the noise stability of iterative algorithms developed for attenuation correction in Fluorescence Confocal Microscopy using FT methods. In each iteration the convolution of the previous estimate is computed. It turns out that the estimators are robust to noise perturbation.

Improved sampling and analysis of images in corneal confocal microscopy.

Science.gov (United States)

Schaldemose, E L; Fontain, F I; Karlsson, P; Nyengaard, J R

2017-10-01

Corneal confocal microscopy (CCM) is a noninvasive clinical method to analyse and quantify corneal nerve fibres in vivo. Although the CCM technique is in constant progress, there are methodological limitations in terms of sampling of images and objectivity of the nerve quantification. The aim of this study was to present a randomized sampling method of the CCM images and to develop an adjusted area-dependent image analysis. Furthermore, a manual nerve fibre analysis method was compared to a fully automated method. 23 idiopathic small-fibre neuropathy patients were investigated using CCM. Corneal nerve fibre length density (CNFL) and corneal nerve fibre branch density (CNBD) were determined in both a manual and automatic manner. Differences in CNFL and CNBD between (1) the randomized and the most common sampling method, (2) the adjusted and the unadjusted area and (3) the manual and automated quantification method were investigated. The CNFL values were significantly lower when using the randomized sampling method compared to the most common method (p = 0.01). There was not a statistical significant difference in the CNBD values between the randomized and the most common sampling method (p = 0.85). CNFL and CNBD values were increased when using the adjusted area compared to the standard area. Additionally, the study found a significant increase in the CNFL and CNBD values when using the manual method compared to the automatic method (p ≤ 0.001). The study demonstrated a significant difference in the CNFL values between the randomized and common sampling method indicating the importance of clear guidelines for the image sampling. The increase in CNFL and CNBD values when using the adjusted cornea area is not surprising. The observed increases in both CNFL and CNBD values when using the manual method of nerve quantification compared to the automatic method are consistent with earlier findings. This study underlines the importance of improving the analysis of the

Evaluation of microwave thermotherapy with histopathology, magnetic resonance imaging and temperature mapping

NARCIS (Netherlands)

Huidobro, Christian; Bolmsjö, Magnus; Larson, Thayne; de la Rosette, Jean; Wagrell, Lennart; Schelin, Sonny; Gorecki, Tomasz; Mattiasson, Anders

2004-01-01

Purpose: Interstitial temperature mapping was used to determine the heat field within the prostate by the Coretherm. (ProstaLund, Lund, Sweden) transurethral microwave thermotherapy device. Gadolinium. enhanced magnetic resonance imaging (MRI) and histopathology were used to determine the extent and

Simultaneous measurement of internal and surrounding flows of a moving droplet using multicolour confocal micro-particle image velocimetry (micro-PIV)

International Nuclear Information System (INIS)

Oishi, M; Kinoshita, H; Fujii, T; Oshima, M

2011-01-01

This paper presents a micro-multiphase flow measurement technique, 'multicolour confocal micro-particle image velocimetry (PIV), and its application to the internal and surrounding flow measurement of a droplet moving through a microchannel. The present system measures the dynamic interaction between flows in two different phases, such as solid–liquid or liquid–liquid, simultaneously and separately. Unlike conventional confocal micro-PIV, this system features a wavelength separation optical device. The optical components (e.g., filters and dichroic mirror) are designed to separate fluorescent lights of tracer particles and to eliminate unnecessary scattered light depending on the characteristic wavelengths. The system can record a sequence of images at up to 2000 frames per second. It also has an in-plane spatial resolution of 0.284 µm/pixel in a field of 227.2 µm × 170.4 µm and a confocal depth of 3.43 µm using 1.0 µm particles and a 40× objective lens. This paper examines the performance of the present system, such as its ability to separate wavelengths. Furthermore, this system is applied to liquid–liquid two-phase flow, which consists of a water droplet and surrounding oil flow, in a microchannel. We succeeded in measuring each phase movement separately and simultaneously. As a result of the estimation of the out-of-plane velocity component, a three-dimensional flow structure is obtained and the interaction between each phase is investigated

Design and analysis of a cross-type structured-illumination confocal microscope for high speed and high resolution

International Nuclear Information System (INIS)

Kim, Young-Duk; Ahn, MyoungKi; Kim, Taejoong; Gweon, DaeGab; Yoo, Hongki

2012-01-01

There have been many studies about a super resolution microscope for many years. A super resolution microscope can detect the physical phenomena or morphology of a biological sample more precisely than conventional microscopes. The structured-illumination microscope (SIM) is one of the technologies that demonstrate super resolution. However, the conventional SIM requires more time to obtain one resolution-enhanced image than other super resolution microscopes. More specifically, the conventional SIM uses three images with a 120° phase difference for each direction and three different directions are image-processed to make one resolution enhancement by increasing the optical transfer function in three directions. In this paper, we present a novel cross structured-illumination confocal microscope (CSICM) that takes the advantage of the technology of both SIM and the confocal microscope. The CSICM uses only two directions with three phase difference images, for a total of six images. By reducing the number of images that must be obtained, the total image acquisition time and image reconstruction time in obtaining the final output images can be decreased, and the confocal microscope provides axial information of the sample automatically. We demonstrate our method of cross illumination and evaluate the performance of the CSICM and compare it to the conventional SIM and the confocal microscope. (paper)

Segmentation of confocal Raman microspectroscopic imaging data using edge-preserving denoising and clustering.

Science.gov (United States)

Alexandrov, Theodore; Lasch, Peter

2013-06-18

Over the past decade, confocal Raman microspectroscopic (CRM) imaging has matured into a useful analytical tool to obtain spatially resolved chemical information on the molecular composition of biological samples and has found its way into histopathology, cytology, and microbiology. A CRM imaging data set is a hyperspectral image in which Raman intensities are represented as a function of three coordinates: a spectral coordinate λ encoding the wavelength and two spatial coordinates x and y. Understanding CRM imaging data is challenging because of its complexity, size, and moderate signal-to-noise ratio. Spatial segmentation of CRM imaging data is a way to reveal regions of interest and is traditionally performed using nonsupervised clustering which relies on spectral domain-only information with the main drawback being the high sensitivity to noise. We present a new pipeline for spatial segmentation of CRM imaging data which combines preprocessing in the spectral and spatial domains with k-means clustering. Its core is the preprocessing routine in the spatial domain, edge-preserving denoising (EPD), which exploits the spatial relationships between Raman intensities acquired at neighboring pixels. Additionally, we propose to use both spatial correlation to identify Raman spectral features colocalized with defined spatial regions and confidence maps to assess the quality of spatial segmentation. For CRM data acquired from midsagittal Syrian hamster ( Mesocricetus auratus ) brain cryosections, we show how our pipeline benefits from the complex spatial-spectral relationships inherent in the CRM imaging data. EPD significantly improves the quality of spatial segmentation that allows us to extract the underlying structural and compositional information contained in the Raman microspectra.

Non-Invasive Imaging Method of Microwave Near Field Based on Solid State Quantum Sensing

OpenAIRE

Yang, Bo; Du, Guanxiang; Dong, Yue; Liu, Guoquan; Hu, Zhenzhong; Wang, Yongjin

2018-01-01

In this paper, we propose a non-invasive imaging method of microwave near field using a diamond containing nitrogen-vacancy centers. We applied synchronous pulsed sequence combined with charge coupled device camera to measure the amplitude of the microwave magnetic field. A full reconstruction formulation of the local field vector, including the amplitude and phase, is developed by measuring both left and right circular polarizations along the four nitrogen-vacancy axes. Compared to the raste...

Noninvasive imaging of the human rod photoreceptor mosaic using a confocal adaptive optics scanning ophthalmoscope

Science.gov (United States)

Dubra, Alfredo; Sulai, Yusufu; Norris, Jennifer L.; Cooper, Robert F.; Dubis, Adam M.; Williams, David R.; Carroll, Joseph

2011-01-01

The rod photoreceptors are implicated in a number of devastating retinal diseases. However, routine imaging of these cells has remained elusive, even with the advent of adaptive optics imaging. Here, we present the first in vivo images of the contiguous rod photoreceptor mosaic in nine healthy human subjects. The images were collected with three different confocal adaptive optics scanning ophthalmoscopes at two different institutions, using 680 and 775 nm superluminescent diodes for illumination. Estimates of photoreceptor density and rod:cone ratios in the 5°–15° retinal eccentricity range are consistent with histological findings, confirming our ability to resolve the rod mosaic by averaging multiple registered images, without the need for additional image processing. In one subject, we were able to identify the emergence of the first rods at approximately 190 μm from the foveal center, in agreement with previous histological studies. The rod and cone photoreceptor mosaics appear in focus at different retinal depths, with the rod mosaic best focus (i.e., brightest and sharpest) being at least 10 μm shallower than the cones at retinal eccentricities larger than 8°. This study represents an important step in bringing high-resolution imaging to bear on the study of rod disorders. PMID:21750765

QUANTITATIVE CONFOCAL LASER SCANNING MICROSCOPY

Directory of Open Access Journals (Sweden)

Merete Krog Raarup

2011-05-01

Full Text Available This paper discusses recent advances in confocal laser scanning microscopy (CLSM for imaging of 3D structure as well as quantitative characterization of biomolecular interactions and diffusion behaviour by means of one- and two-photon excitation. The use of CLSM for improved stereological length estimation in thick (up to 0.5 mm tissue is proposed. The techniques of FRET (Fluorescence Resonance Energy Transfer, FLIM (Fluorescence Lifetime Imaging Microscopy, FCS (Fluorescence Correlation Spectroscopy and FRAP (Fluorescence Recovery After Photobleaching are introduced and their applicability for quantitative imaging of biomolecular (co-localization and trafficking in live cells described. The advantage of two-photon versus one-photon excitation in relation to these techniques is discussed.

Simultaneous Confocal Scanning Laser Ophthalmoscopy Combined with High-Resolution Spectral-Domain Optical Coherence Tomography: A Review

Directory of Open Access Journals (Sweden)

Verônica Castro Lima

2011-01-01

Full Text Available We aimed to evaluate technical aspects and the clinical relevance of a simultaneous confocal scanning laser ophthalmoscope and a high-speed, high-resolution, spectral-domain optical coherence tomography (SDOCT device for retinal imaging. The principle of confocal scanning laser imaging provides a high resolution of retinal and choroidal vasculature with low light exposure. Enhanced contrast, details, and image sharpness are generated using confocality. The real-time SDOCT provides a new level of accuracy for assessment of the angiographic and morphological correlation. The combined system allows for simultaneous recordings of topographic and tomographic images with accurate correlation between them. Also it can provide simultaneous multimodal imaging of retinal pathologies, such as fluorescein and indocyanine green angiographies, infrared and blue reflectance (red-free images, fundus autofluorescence images, and OCT scans (Spectralis HRA + OCT; Heidelberg Engineering, Heidelberg, Germany. The combination of various macular diagnostic tools can lead to a better understanding and improved knowledge of macular diseases.

The EUMETSAT Polar System - Second Generation (EPS-SG) micro-wave imaging (MWI) mission

Science.gov (United States)

Bojkov, B. R.; Accadia, C.; Klaes, D.; Canestri, A.; Cohen, M.

2017-12-01

The EUMETSAT Polar System (EPS) will be followed by a second generation system called EPS-SG. This new family of missions will contribute to the Joint Polar System being jointly set up with NOAA in the timeframe 2020-2040. These satellites will fly, like Metop (EPS), in a sun synchronous, low earth orbit at 830 km altitude and 09:30 local time descending node, providing observations over the full globe with revisit times of 12 hours. EPS-SG consists of two different satellites configurations, the EPS-SGa series dedicated to IR and MW sounding, and the EPS-SGb series dedicated to microwave imaging and scatterometry. The EPS-SG family will consist of three successive launches of each satellite-type. The Microwave Imager (MWI) will be hosted on Metop-SGb series of satellites, with the primary objective of supporting Numerical Weather Prediction (NWP) at regional and global scales. Other applications will be observation of surface parameters such as sea ice concentration and hydrology applications. The 18 MWI instrument frequencies range from 18.7 GHz to 183 GHz. All MWI channels up to 89 GHz will measure V- and H polarizations. The MWI was also designed to provide continuity of measurements for select heritage microwave imager channels (e.g. SSM/I, AMSR-E). The additional sounding channels such as the 50-55 and 118 GHz bands will provide additional cloud and precipitation information over sea and land. This combination of channels was successfully tested on the NPOESS Aircraft Sounder Testbed - Microwave Sounder (NAST-M) airborne radiometer, and it is the first time that will be implemented in a conical scanning configuration in a single instrument. An overview of the EPS-SG programme and the MWI instrument will be presented.

Confocal imaging of whole vertebrate embryos reveals novel insights into molecular and cellular mechanisms of organ development

Science.gov (United States)

Hadel, Diana M.; Keller, Bradley B.; Sandell, Lisa L.

2014-03-01

Confocal microscopy has been an invaluable tool for studying cellular or sub-cellular biological processes. The study of vertebrate embryology is based largely on examination of whole embryos and organs. The application of confocal microscopy to immunostained whole mount embryos, combined with three dimensional (3D) image reconstruction technologies, opens new avenues for synthesizing molecular, cellular and anatomical analysis of vertebrate development. Optical cropping of the region of interest enables visualization of structures that are morphologically complex or obscured, and solid surface rendering of fluorescent signal facilitates understanding of 3D structures. We have applied these technologies to whole mount immunostained mouse embryos to visualize developmental morphogenesis of the mammalian inner ear and heart. Using molecular markers of neuron development and transgenic reporters of neural crest cell lineage we have examined development of inner ear neurons that originate from the otic vesicle, along with the supporting glial cells that derive from the neural crest. The image analysis reveals a previously unrecognized coordinated spatial organization between migratory neural crest cells and neurons of the cochleovestibular nerve. The images also enable visualization of early cochlear spiral nerve morphogenesis relative to the developing cochlea, demonstrating a heretofore unknown association of neural crest cells with extending peripheral neurite projections. We performed similar analysis of embryonic hearts in mouse and chick, documenting the distribution of adhesion molecules during septation of the outflow tract and remodeling of aortic arches. Surface rendering of lumen space defines the morphology in a manner similar to resin injection casting and micro-CT.

Toward real-time virtual biopsy of oral lesions using confocal laser endomicroscopy interfaced with embedded computing.

Science.gov (United States)

Thong, Patricia S P; Tandjung, Stephanus S; Movania, Muhammad Mobeen; Chiew, Wei-Ming; Olivo, Malini; Bhuvaneswari, Ramaswamy; Seah, Hock-Soon; Lin, Feng; Qian, Kemao; Soo, Khee-Chee

2012-05-01

Oral lesions are conventionally diagnosed using white light endoscopy and histopathology. This can pose a challenge because the lesions may be difficult to visualise under white light illumination. Confocal laser endomicroscopy can be used for confocal fluorescence imaging of surface and subsurface cellular and tissue structures. To move toward real-time "virtual" biopsy of oral lesions, we interfaced an embedded computing system to a confocal laser endomicroscope to achieve a prototype three-dimensional (3-D) fluorescence imaging system. A field-programmable gated array computing platform was programmed to enable synchronization of cross-sectional image grabbing and Z-depth scanning, automate the acquisition of confocal image stacks and perform volume rendering. Fluorescence imaging of the human and murine oral cavities was carried out using the fluorescent dyes fluorescein sodium and hypericin. Volume rendering of cellular and tissue structures from the oral cavity demonstrate the potential of the system for 3-D fluorescence visualization of the oral cavity in real-time. We aim toward achieving a real-time virtual biopsy technique that can complement current diagnostic techniques and aid in targeted biopsy for better clinical outcomes.

Fluorescence (Multiwave) Confocal Microscopy.

Science.gov (United States)

Welzel, J; Kästle, Raphaela; Sattler, Elke C

2016-10-01

In addition to reflectance confocal microscopy, multiwave confocal microscopes with different laser wavelengths in combination with exogenous fluorophores allow fluorescence mode confocal microscopy in vivo and ex vivo. Fluorescence mode confocal microscopy improves the contrast between the epithelium and the surrounding soft tissue and allows the depiction of certain structures, like epithelial tumors, nerves, and glands. Copyright © 2016 Elsevier Inc. All rights reserved.

Three-dimensional measurement and visualization of internal flow of a moving droplet using confocal micro-PIV.

Science.gov (United States)

Kinoshita, Haruyuki; Kaneda, Shohei; Fujii, Teruo; Oshima, Marie

2007-03-01

This paper presents a micro-flow diagnostic technique, 'high-speed confocal micro-particle image velocimetry (PIV)', and its application to the internal flow measurement of a droplet passing through a microchannel. A confocal micro-PIV system has been successfully constructed wherein a high-speed confocal scanner is combined with the conventional micro-PIV technique. The confocal micro-PIV system enables us to obtain a sequence of sharp and high-contrast cross-sectional particle images at 2000 frames s(-1). This study investigates the confocal depth, which is a significant parameter to determine the out-of-plane measurement resolution in confocal micro-PIV. Using the present confocal micro-PIV system, we can measure velocity distributions of micro-flows in a 228 microm x 171 microm region with a confocal depth of 1.88 microm. We also propose a three-dimensional velocity measurement method based on the confocal micro-PIV and the equation of continuity. This method enables us to measure three velocity components in a three-dimensional domain of micro flows. The confocal micro-PIV system is applied to the internal flow measurement of a droplet. We have measured three-dimensional distributions of three-component velocities of a droplet traveling in a 100 microm (width) x 58 microm (depth) channel. A volumetric velocity distribution inside a droplet is obtained by the confocal micro-PIV and the three-dimensional flow structure inside the droplet is investigated. The measurement results suggest that a three-dimensional and complex circulating flow is formed inside the droplet.

Image and pathological changes after microwave ablation of breast cancer: A pilot study

Energy Technology Data Exchange (ETDEWEB)

Zhou, Wenbin [Department of Breast Surgery, The First Affiliated Hospital, Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029 (China); Jiang, Yanni [Department of Radiology, The First Affiliated Hospital, Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029 (China); Chen, Lin; Ling, Lijun; Liang, Mengdi; Pan, Hong [Department of Breast Surgery, The First Affiliated Hospital, Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029 (China); Wang, Siqi [Department of Radiology, The First Affiliated Hospital, Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029 (China); Ding, Qiang [Department of Breast Surgery, The First Affiliated Hospital, Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029 (China); Liu, Xiaoan, E-mail: liuxiaoan@126.com [Department of Breast Surgery, The First Affiliated Hospital, Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029 (China); Wang, Shui, E-mail: ws0801@hotmail.com [Department of Breast Surgery, The First Affiliated Hospital, Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029 (China)

2014-10-15

Highlights: • We report successful experience of MWA in breast cancer under local anesthesia. • We report MR imaging evaluation of microwave ablation zone in breast cancer. • Pathological changes after microwave ablation in breast cancer was reported. • 2 min MWA caused an ablation zone with three diameters > 2 cm in breast cancer. - Abstract: Purpose: To prospectively assess MR imaging evaluation of the ablation zone and pathological changes after microwave ablation (MWA) in breast cancer. Materials and methods: Twelve enrolled patients, diagnosed with non-operable locally advanced breast cancer (LABC), were treated by MWA and then neoadjuvant chemotherapy, followed by surgery. MR imaging was applied to evaluate the effect of MWA. Hematoxylin-eosin (HE) staining and transmission electron microscopy (TEM) were applied to analyze the ablated area. Results: All MWA procedures were performed successfully under local anesthesia. For a mean duration of 2.15 min, the mean largest, middle and smallest diameters in the ablated zone 24-h post-ablation in MR imaging were 2.98 cm ± 0.53, 2.51 cm ± 0.41 and 2.23 cm ± 0.41, respectively. The general shape of the ablation zone was close to a sphere. The ablated area became gradually smaller in MR imaging. No adverse effects related to MWA were noted in all 12 patients during and after MWA. HE staining could confirm the effect about 3 months after MWA, which was confirmed by TEM. Conclusions: 2 min MWA can cause an ablation zone with three diameters larger than 2 cm in breast cancer, which may be suitable for the local treatment of breast cancer up to 2 cm in largest diameter. However, the long-term effect of MWA in the treatment of small breast cancer should be determined in the future.

3D Volumetric Analysis of Fluid Inclusions Using Confocal Microscopy

Science.gov (United States)

Proussevitch, A.; Mulukutla, G.; Sahagian, D.; Bodnar, B.

2009-05-01

Fluid inclusions preserve valuable information regarding hydrothermal, metamorphic, and magmatic processes. The molar quantities of liquid and gaseous components in the inclusions can be estimated from their volumetric measurements at room temperatures combined with knowledge of the PVTX properties of the fluid and homogenization temperatures. Thus, accurate measurements of inclusion volumes and their two phase components are critical. One of the greatest advantages of the Laser Scanning Confocal Microscopy (LSCM) in application to fluid inclsion analsyis is that it is affordable for large numbers of samples, given the appropriate software analysis tools and methodology. Our present work is directed toward developing those tools and methods. For the last decade LSCM has been considered as a potential method for inclusion volume measurements. Nevertheless, the adequate and accurate measurement by LSCM has not yet been successful for fluid inclusions containing non-fluorescing fluids due to many technical challenges in image analysis despite the fact that the cost of collecting raw LSCM imagery has dramatically decreased in recent years. These problems mostly relate to image analysis methodology and software tools that are needed for pre-processing and image segmentation, which enable solid, liquid and gaseous components to be delineated. Other challenges involve image quality and contrast, which is controlled by fluorescence of the material (most aqueous fluid inclusions do not fluoresce at the appropriate laser wavelengths), material optical properties, and application of transmitted and/or reflected confocal illumination. In this work we have identified the key problems of image analysis and propose some potential solutions. For instance, we found that better contrast of pseudo-confocal transmitted light images could be overlayed with poor-contrast true-confocal reflected light images within the same stack of z-ordered slices. This approach allows one to narrow

Rose Bengal Photothrombosis by Confocal Optical Imaging In Vivo: A Model of Single Vessel Stroke.

Science.gov (United States)

Talley Watts, Lora; Zheng, Wei; Garling, R Justin; Frohlich, Victoria C; Lechleiter, James Donald

2015-06-23

In vivo imaging techniques have increased in utilization due to recent advances in imaging dyes and optical technologies, allowing for the ability to image cellular events in an intact animal. Additionally, the ability to induce physiological disease states such as stroke in vivo increases its utility. The technique described herein allows for physiological assessment of cellular responses within the CNS following a stroke and can be adapted for other pathological conditions being studied. The technique presented uses laser excitation of the photosensitive dye Rose Bengal in vivo to induce a focal ischemic event in a single blood vessel. The video protocol demonstrates the preparation of a thin-skulled cranial window over the somatosensory cortex in a mouse for the induction of a Rose Bengal photothrombotic event keeping injury to the underlying dura matter and brain at a minimum. Surgical preparation is initially performed under a dissecting microscope with a custom-made surgical/imaging platform, which is then transferred to a confocal microscope equipped with an inverted objective adaptor. Representative images acquired utilizing this protocol are presented as well as time-lapse sequences of stroke induction. This technique is powerful in that the same area can be imaged repeatedly on subsequent days facilitating longitudinal in vivo studies of pathological processes following stroke.

Spinning-disk confocal microscopy: present technology and future trends.

Science.gov (United States)

Oreopoulos, John; Berman, Richard; Browne, Mark

2014-01-01

Live-cell imaging requires not only high temporal resolution but also illumination powers low enough to minimize photodamage. Traditional single-point laser scanning confocal microscopy (LSCM) is generally limited by both the relatively slow speed at which it can acquire optical sections by serial raster scanning (a few Hz) and the higher potential for phototoxicity. These limitations have driven the development of rapid, parallel forms of confocal microscopy, the most popular of which is the spinning-disk confocal microscope (SDCM). Here, we briefly introduce the SDCM technique, discuss its strengths and weaknesses against LSCM, and update the reader on some recent developments in SDCM technology that improve its performance and expand its utility for life science research now and in the future. © 2014 Elsevier Inc. All rights reserved.

Nonlinear 3-D Microwave Imaging for Breast-Cancer Screening: Log, Phase, and Log-Phase Formulation

DEFF Research Database (Denmark)

Jensen, Peter Damsgaard; Rubæk, Tonny; Mohr, Johan Jacob

2011-01-01

The imaging algorithm used in the 3-D microwave imaging system for breast cancer screening, currently being developed at the Technical University of Denmark, is based on an iterative Newton-type algorithm. In this algorithm, the distribution of the electromagnetic constitutive parameters is updat...

Reprocessing the Historical Satellite Passive Microwave Record at Enhanced Spatial Resolutions using Image Reconstruction

Science.gov (United States)

Hardman, M.; Brodzik, M. J.; Long, D. G.; Paget, A. C.; Armstrong, R. L.

2015-12-01

Beginning in 1978, the satellite passive microwave data record has been a mainstay of remote sensing of the cryosphere, providing twice-daily, near-global spatial coverage for monitoring changes in hydrologic and cryospheric parameters that include precipitation, soil moisture, surface water, vegetation, snow water equivalent, sea ice concentration and sea ice motion. Currently available global gridded passive microwave data sets serve a diverse community of hundreds of data users, but do not meet many requirements of modern Earth System Data Records (ESDRs) or Climate Data Records (CDRs), most notably in the areas of intersensor calibration, quality-control, provenance and consistent processing methods. The original gridding techniques were relatively primitive and were produced on 25 km grids using the original EASE-Grid definition that is not easily accommodated in modern software packages. Further, since the first Level 3 data sets were produced, the Level 2 passive microwave data on which they were based have been reprocessed as Fundamental CDRs (FCDRs) with improved calibration and documentation. We are funded by NASA MEaSUREs to reprocess the historical gridded data sets as EASE-Grid 2.0 ESDRs, using the most mature available Level 2 satellite passive microwave (SMMR, SSM/I-SSMIS, AMSR-E) records from 1978 to the present. We have produced prototype data from SSM/I and AMSR-E for the year 2003, for review and feedback from our Early Adopter user community. The prototype data set includes conventional, low-resolution ("drop-in-the-bucket" 25 km) grids and enhanced-resolution grids derived from the two candidate image reconstruction techniques we are evaluating: 1) Backus-Gilbert (BG) interpolation and 2) a radiometer version of Scatterometer Image Reconstruction (SIR). We summarize our temporal subsetting technique, algorithm tuning parameters and computational costs, and include sample SSM/I images at enhanced resolutions of up to 3 km. We are actively

Mapping the intracellular distribution of carbon nanotubes after targeted delivery to carcinoma cells using confocal Raman imaging as a label-free technique

International Nuclear Information System (INIS)

Lamprecht, C; Unterauer, B; Plochberger, B; Brameshuber, M; Hinterdorfer, P; Ebner, A; Gierlinger, N; Hild, S; Heister, E

2012-01-01

The uptake of carbon nanotubes (CNTs) by mammalian cells and their distribution within cells is being widely studied in recent years due to their increasing use for biomedical purposes. The two main imaging techniques used are confocal fluorescence microscopy and transmission electron microscopy (TEM). The former, however, requires labeling of the CNTs with fluorescent dyes, while the latter is a work-intensive technique that is unsuitable for in situ bio-imaging. Raman spectroscopy, on the other hand, presents a direct, straightforward and label-free alternative. Confocal Raman microscopy can be used to image the CNTs inside cells, exploiting the strong Raman signal connected to different vibrational modes of the nanotubes. In addition, cellular components, such as the endoplasmic reticulum and the nucleus, can be mapped. We first validate our method by showing that only when using the CNTs’ G band for intracellular mapping accurate results can be obtained, as mapping of the radial breathing mode (RBM) only shows a small fraction of CNTs. We then take a closer look at the exact localization of the nanotubes inside cells after folate receptor-mediated endocytosis and show that, after 8-10 h incubation, the majority of CNTs are localized around the nucleus. In summary, Raman imaging has enormous potential for imaging CNTs inside cells, which is yet to be fully realized. (paper)

Imaging Amyloid Tissues Stained with Luminescent Conjugated Oligothiophenes by Hyperspectral Confocal Microscopy and Fluorescence Lifetime Imaging.

Science.gov (United States)

Nyström, Sofie; Bäck, Marcus; Nilsson, K Peter R; Hammarström, Per

2017-10-20

Proteins that deposit as amyloid in tissues throughout the body can be the cause or consequence of a large number of diseases. Among these we find neurodegenerative diseases such as Alzheimer's and Parkinson's disease afflicting primarily the central nervous system, and systemic amyloidosis where serum amyloid A, transthyretin and IgG light chains deposit as amyloid in liver, carpal tunnel, spleen, kidney, heart, and other peripheral tissues. Amyloid has been known and studied for more than a century, often using amyloid specific dyes such as Congo red and Thioflavin T (ThT) or Thioflavin (ThS). In this paper, we present heptamer-formyl thiophene acetic acid (hFTAA) as an example of recently developed complements to these dyes called luminescent conjugated oligothiophenes (LCOs). hFTAA is easy to use and is compatible with co-staining in immunofluorescence or with other cellular markers. Extensive research has proven that hFTAA detects a wider range of disease associated protein aggregates than conventional amyloid dyes. In addition, hFTAA can also be applied for optical assignment of distinct aggregated morphotypes to allow studies of amyloid fibril polymorphism. While the imaging methodology applied is optional, we here demonstrate hyperspectral imaging (HIS), laser scanning confocal microscopy and fluorescence lifetime imaging (FLIM). These examples show some of the imaging techniques where LCOs can be used as tools to gain more detailed knowledge of the formation and structural properties of amyloids. An important limitation to the technique is, as for all conventional optical microscopy techniques, the requirement for microscopic size of aggregates to allow detection. Furthermore, the aggregate should comprise a repetitive β-sheet structure to allow for hFTAA binding. Excessive fixation and/or epitope exposure that modify the aggregate structure or conformation can render poor hFTAA binding and hence pose limitations to accurate imaging.

Bacterial and abiotic decay in waterlogged archaeological Picea abies (L.) Karst studied by confocal Raman imaging and ATR-FTIR spectroscopy

DEFF Research Database (Denmark)

Pedersen, Nanna Bjerregaard; Gierlinger, Notburga; Thygesen, Lisbeth Garbrecht

2015-01-01

Waterlogged archaeological Norway spruce [Picea abies (L.) Karst] poles were studied by means of confocal Raman imaging (CRI) and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) analysis to determine lignin and polysaccharide composition and distribution in the cell......, and minor oxidation of the lignin polymer compared to recent reference material. This is evidence for abiotic decay in the course of waterlogging....

Whole-body ring-shaped confocal photoacoustic computed tomography of small animals in vivo

Science.gov (United States)

Xia, Jun; Chatni, Muhammad R.; Maslov, Konstantin; Guo, Zijian; Wang, Kun; Anastasio, Mark; Wang, Lihong V.

2012-05-01

We report a novel small-animal whole-body imaging system called ring-shaped confocal photoacoustic computed tomography (RC-PACT). RC-PACT is based on a confocal design of free-space ring-shaped light illumination and 512-element full-ring ultrasonic array signal detection. The free-space light illumination maximizes the light delivery efficiency, and the full-ring signal detection ensures a full two-dimensional view aperture for accurate image reconstruction. Using cylindrically focused array elements, RC-PACT can image a thin cross section with 0.10 to 0.25 mm in-plane resolutions and 1.6 s/frame acquisition time. By translating the mouse along the elevational direction, RC-PACT provides a series of cross-sectional images of the brain, liver, kidneys, and bladder.

Imaging subsurface damage of grinded fused silica optics by confocal fluorescence microscopy

International Nuclear Information System (INIS)

Neauport, J.; Cormont, P.; Destribats, J.; Legros, P.; Ambard, C.

2009-01-01

We report an experimental investigation of fluorescence confocal microscopy as a tool to measure subsurface damage on grinded fused silica optics. Confocal fluorescence microscopy was performed with an excitation at the wavelength of 405 nm on fixed abrasive diamond grinded fused silica samples. We detail the measured fluorescence spectrums and compare them to those of oil based coolants and grinding slurries. We evidence that oil based coolant used in diamond grinding induces a fluorescence that marks the subsurface damages and eases its observation. Such residual traces might also be involved in the laser damage process. (authors)

Hierarchy of Electronic Properties of Chemically Derived and Pristine Graphene Probed by Microwave Imaging

KAUST Repository

Kundhikanjana, Worasom

2009-11-11

Local electrical imaging using microwave impedance microscope is performed on graphene in different modalities, yielding a rich hierarchy of the local conductivity. The low-conductivity graphite oxide and its derivatives show significant electronic inhomogeneity. For the conductive chemical graphene, the residual defects lead to a systematic reduction of the microwave signals. In contrast, the signals on pristine graphene agree well with a lumped-element circuit model. The local impedance information can also be used to verify the electrical contact between overlapped graphene pieces. © 2009 American Chemical Society.

Confocal absorption spectral imaging of MoS2: optical transitions depending on the atomic thickness of intrinsic and chemically doped MoS2.

Science.gov (United States)

Dhakal, Krishna P; Duong, Dinh Loc; Lee, Jubok; Nam, Honggi; Kim, Minsu; Kan, Min; Lee, Young Hee; Kim, Jeongyong

2014-11-07

We performed a nanoscale confocal absorption spectral imaging to obtain the full absorption spectra (over the range 1.5-3.2 eV) within regions having different numbers of layers and studied the variation of optical transition depending on the atomic thickness of the MoS2 film. Three distinct absorption bands corresponding to A and B excitons and a high-energy background (BG) peak at 2.84 eV displayed a gradual redshift as the MoS2 film thickness increased from the monolayer, to the bilayer, to the bulk MoS2 and this shift was attributed to the reduction of the gap energy in the Brillouin zone at the K-point as the atomic thickness increased. We also performed n-type chemical doping of MoS2 films using reduced benzyl viologen (BV) and the confocal absorption spectra modified by the doping showed a strong dependence on the atomic thickness: A and B exciton peaks were greatly quenched in the monolayer MoS2 while much less effect was shown in larger thickness and the BG peak either showed very small quenching for 1 L MoS2 or remained constant for larger thicknesses. Our results indicate that confocal absorption spectral imaging can provide comprehensive information on optical transitions of microscopic size intrinsic and doped two-dimensional layered materials.

Surface scanning through a cylindrical tank of coupling fluid for clinical microwave breast imaging exams

International Nuclear Information System (INIS)

Pallone, Matthew J.; Meaney, Paul M.; Paulsen, Keith D.

2012-01-01

Purpose: Microwave tomographic image quality can be improved significantly with prior knowledge of the breast surface geometry. The authors have developed a novel laser scanning system capable of accurately recovering surface renderings of breast-shaped phantoms immersed within a cylindrical tank of coupling fluid which resides completely external to the tank (and the aqueous environment) and overcomes the challenges associated with the optical distortions caused by refraction from the air, tank wall, and liquid bath interfaces. Methods: The scanner utilizes two laser line generators and a small CCD camera mounted concentrically on a rotating gantry about the microwave imaging tank. Various calibration methods were considered for optimizing the accuracy of the scanner in the presence of the optical distortions including traditional ray tracing and image registration approaches. In this paper, the authors describe the construction and operation of the laser scanner, compare the efficacy of several calibration methods—including analytical ray tracing and piecewise linear, polynomial, locally weighted mean, and thin-plate-spline (TPS) image registrations—and report outcomes from preliminary phantom experiments. Results: The results show that errors in calibrating camera angles and position prevented analytical ray tracing from achieving submillimeter accuracy in the surface renderings obtained from our scanner configuration. Conversely, calibration by image registration reliably attained mean surface errors of less than 0.5 mm depending on the geometric complexity of the object scanned. While each of the image registration approaches outperformed the ray tracing strategy, the authors found global polynomial methods produced the best compromise between average surface error and scanner robustness. Conclusions: The laser scanning system provides a fast and accurate method of three dimensional surface capture in the aqueous environment commonly found in microwave

Spatiotemporal closure of fractional laser-ablated channels imaged by optical coherence tomography and reflectance confocal microscopy

DEFF Research Database (Denmark)

Banzhaf, Christina A.; Wind, Bas S.; Mogensen, Mette

2016-01-01

Background and Objective Optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) offer high-resolution optical imaging of the skin, which may provide benefit in the context of laser-assisted drug delivery. We aimed to characterize postoperative healing of ablative fractional...... laser (AFXL)-induced channels and dynamics in their spatiotemporal closure using in vivo OCT and RCM techniques. Study design/Materials and Methods The inner forearm of healthy subjects (n = 6) was exposed to 10,600 nm fractional CO2 laser using 5 and 25% densities, 120 μm beam diameter, 5, 15, and 25 m......J/microbeam. Treatment sites were scanned with OCT to evaluate closure of AFXL-channels and RCM to evaluate subsequent re-epithelialization. Results OCT and RCM identified laser channels in epidermis and upper dermis as black, ablated tissue defects surrounded by characteristic hyper-and hyporeflective zones. OCT imaged...

[Contribution of confocal microscopy and anterior chamber OCT to the study of corneal endothelial pathologies].

Science.gov (United States)

Fayol, N; Labbé, A; Dupont-Monod, S; Dupas, B; Baudouin, C

2007-04-01

To describe the appearance of various endothelial diseases with in vivo confocal microscopy and anterior chamber optical coherence tomography (AC OCT). In this study, ten patients with five different corneal endothelial pathologies were evaluated. Three patients had cornea guttata, three had corneal endothelial precipitates, two had irido-corneo-endothelial (ICE) syndrome, one had endothelial folds, and one had breaks in the Descemet membrane. All patients had bilateral ophthalmologic examinations, in vivo confocal microscopy, and AC OCT analysis. In cases of cornea guttata, AC OCT showed a finely embossed line corresponding to the empty intercellular cavities found with in vivo confocal microscopy. Corneal endothelium precipitates had the aspect of round formations suspended with the endothelium. Iris atrophy and irido-corneal synechiae resulting from ICE syndrome were precisely visualized with the AC OCT. High-resolution images of the anterior segment could be obtained using the AC OCT. Associated with in vivo confocal microscopy, these two new imaging techniques provide a precise evaluation of endothelial pathologies.

Reflectance Confocal Microscopy in Lentigo Maligna.

Science.gov (United States)

Gamo, R; Pampín, A; Floristán, U

2016-12-01

Lentigo maligna is the most common type of facial melanoma. Diagnosis is complicated, however, as it shares clinical and dermoscopic characteristics with other cutaneous lesions of the face. Reflectance confocal microscopy is an imaging technique that permits the visualization of characteristic features of lentigo maligna. These include a disrupted honeycomb pattern and pagetoid cells with a tendency to show folliculotropism. These cells typically have a dendritic morphology, although they may also appear as round cells measuring over 20μm with atypical nuclei. Poorly defined dermal papillae and atypical cells may be seen at the dermal-epidermal junction and can form bridges resembling mitochondrial structures. Other characteristic findings include junctional swelling with atypical cells located around the follicles, resembling caput medusae. Reflectance confocal microscopy is a very useful tool for diagnosing lentigo maligna. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

A model for atmospheric brightness temperatures observed by the special sensor microwave imager (SSM/I)

Science.gov (United States)

Petty, Grant W.; Katsaros, Kristina B.

1989-01-01

A closed-form mathematical model for the atmospheric contribution to microwave the absorption and emission at the SSM/I frequencies is developed in order to improve quantitative interpretation of microwave imagery from the Special Sensor Microwave Imager (SSM/I). The model is intended to accurately predict upwelling and downwelling atmospheric brightness temperatures at SSM/I frequencies, as functions of eight input parameters: the zenith (nadir) angle, the integrated water vapor and vapor scale height, the integrated cloud water and cloud height, the effective surface temperature, atmospheric lapse rate, and surface pressure. It is shown that the model accurately reproduces clear-sky brightness temperatures computed by explicit integration of a large number of radiosonde soundings representing all maritime climate zones and seasons.

Wide-band antenna design for use in minimal-scan, microwave tomographic imaging

Science.gov (United States)

Klaser, Jacob

Microwave tomography is widely used in biomedical imaging and nondestructive evaluation of dielectric materials. A novel microwave tomography system that uses an electrically-conformable mirror to steer the incident energy for producing multi-view projection data is being developed in the Non-Destructive Evaluation Laboratory (NDEL). Such a system will have a significant advantage over existing tomography systems in terms of simplicity of design and operation, particularly when there is limited-access of the structure that is being imaged. The major components of a mirror-based tomography system are the source mirror assembly, and a receiver array for capturing the multi-view projection data. This thesis addresses the design and development of the receiver array. This imaging array features balanced, anti-podal Vivaldi antennas, which offer large bandwidth, high gain and a compact size. From the simulations, as well as the experimental results for the antenna, the return loss (S 11) is below -10dB for the range from 2.2GHz to 8.2GHz, and the gain is measured to be near 6dB. The data gathered from the receiver array is then run through MATLAB code for tomographic reconstruction using the Filtered Back-Propagation algorithm from limited-view projections. Initial results of reconstruction from the measured data shows the feasibility of the approach, but a significant challenge remains in interpolating the data for a limited number of receiving antenna elements and removing noise from the reconstructed image.

PIV as a method for quantifying root cell growth and particle displacement in confocal images.

Science.gov (United States)

Bengough, A Glyn; Hans, Joachim; Bransby, M Fraser; Valentine, Tracy A

2010-01-01

Particle image velocimetry (PIV) quantifies displacement of patches of pixels between successive images. We evaluated PIV as a tool for microscopists by measuring displacements of cells and of a surrounding granular medium in confocal laser scanning microscopy images of Arabidopsis thaliana roots labeled with cell-membrane targeted green fluorescent protein. Excellent accuracy (e.g., displacement standard deviation PIV-predicted and actual displacements (r(2) > 0.83). Root mean squared error for these distorted images was 0.4-1.1 pixels, increasing at higher magnification factors. Cell growth and rhizosphere deformation were tracked with good temporal (e.g., 1-min interval) and spatial resolution, with PIV patches located on recognizable cell features being tracked more successfully. Appropriate choice of GFP-label was important to decrease small-scale biological noise due to intracellular motion. PIV of roots grown in stiff 2% versus 0.7% agar showed patterns of cell expansion consistent with physically impeded roots of other species. Roots in glass ballotini underwent rapid changes in growth direction on a timescale of minutes, associated with localized arching of ballotini. By tracking cell vertices, we monitored automatically cell length, width, and area every minute for 0.5 h for cells in different stages of development. In conclusion, PIV measured displacements successfully in images of living root cells and the external granular medium, revealing much potential for use by microscopists. (c) 2009 Wiley-Liss, Inc.

Quantitative Analysis of Subcellular Distribution of the SUMO Conjugation System by Confocal Microscopy Imaging.

Science.gov (United States)

Mas, Abraham; Amenós, Montse; Lois, L Maria

2016-01-01

Different studies point to an enrichment in SUMO conjugation in the cell nucleus, although non-nuclear SUMO targets also exist. In general, the study of subcellular localization of proteins is essential for understanding their function within a cell. Fluorescence microscopy is a powerful tool for studying subcellular protein partitioning in living cells, since fluorescent proteins can be fused to proteins of interest to determine their localization. Subcellular distribution of proteins can be influenced by binding to other biomolecules and by posttranslational modifications. Sometimes these changes affect only a portion of the protein pool or have a partial effect, and a quantitative evaluation of fluorescence images is required to identify protein redistribution among subcellular compartments. In order to obtain accurate data about the relative subcellular distribution of SUMO conjugation machinery members, and to identify the molecular determinants involved in their localization, we have applied quantitative confocal microscopy imaging. In this chapter, we will describe the fluorescent protein fusions used in these experiments, and how to measure, evaluate, and compare average fluorescence intensities in cellular compartments by image-based analysis. We show the distribution of some components of the Arabidopsis SUMOylation machinery in epidermal onion cells and how they change their distribution in the presence of interacting partners or even when its activity is affected.

Reflectance confocal microscopy features of thin versus thick melanomas.

Science.gov (United States)

Kardynal, Agnieszka; Olszewska, Małgorzata; de Carvalho, Nathalie; Walecka, Irena; Pellacani, Giovanni; Rudnicka, Lidia

2018-01-24

In vivo reflectance confocal microscopy (RCM) plays an increasingly important role in differential diagnosis of melanoma. The aim of the study was to assess typical confocal features of thin (≤1mm according to Breslow index) versus thick (>1mm) melanomas. 30 patients with histopathologically confirmed cutaneous melanoma were included in the study. Reflectance confocal microscopy was performed with Vivascope equipment prior to excision. Fifteen melanomas were thin (Breslow thickness ≤ 1mm) and 15 were thick melanomas (Breslow thickness >1mm). In the RCM examination, the following features were more frequently observed in thin compared to thick melanomas: edged papillae (26.7% vs 0%, p=0.032) and areas with honeycomb or cobblestone pattern (33.3% vs 6.7%, p=0.068). Both features are present in benign melanocytic lesions, so in melanoma are good prognostic factors. The group of thick melanomas compared to the group of thin melanomas in the RCM images presented with greater frequency of roundish cells (100% vs 40%, p=0.001), non-edged papillae (100% vs 60%, p=0.006), numerous pagetoid cells (73.3% vs 33.3%, p=0.028), numerous atypical cells at dermal-epidermal junction (53.3% vs 20%, p=0.058) and epidermal disarray (93.3% vs 66.7%, p=0.068). Non-invasive imaging methods helps in deepening of knowledge about the evolution and biology of melanoma. The most characteristic features for thin melanomas in confocal examination are: fragments of cobblestone or honeycomb pattern and edged papillae (as good prognostic factors). The features of thick melanomas in RCM examination are: roundish cells, non-edged papillae, numerous pagetoid cells at dermal-epidermal junction and epidermal disarray.

Ca(2+ release events in cardiac myocytes up close: insights from fast confocal imaging.

Directory of Open Access Journals (Sweden)

Vyacheslav M Shkryl

Full Text Available The spatio-temporal properties of Ca(2+ transients during excitation-contraction coupling and elementary Ca(2+ release events (Ca(2+ sparks were studied in atrial and ventricular myocytes with ultra-fast confocal microscopy using a Zeiss LSM 5 LIVE system that allows sampling rates of up to 60 kHz. Ca(2+ sparks which originated from subsarcolemmal junctional sarcoplasmic reticulum (j-SR release sites in atrial myocytes were anisotropic and elongated in the longitudinal direction of the cell. Ca(2+ sparks in atrial cells originating from non-junctional SR and in ventricular myocytes were symmetrical. Ca(2+ spark recording in line scan mode at 40,000 lines/s uncovered step-like increases of [Ca(2+]i. 2-D imaging of Ca(2+ transients revealed an asynchronous activation of release sites and allowed the sequential recording of Ca(2+ entry through surface membrane Ca(2+ channels and subsequent activation of Ca(2+-induced Ca(2+ release. With a latency of 2.5 ms after application of an electrical stimulus, Ca(2+ entry could be detected that was followed by SR Ca(2+ release after an additional 3 ms delay. Maximum Ca(2+ release was observed 4 ms after the beginning of release. The timing of Ca(2+ entry and release was confirmed by simultaneous [Ca(2+]i and membrane current measurements using the whole cell voltage-clamp technique. In atrial cells activation of discrete individual release sites of the j-SR led to spatially restricted Ca(2+ release events that fused into a peripheral ring of elevated [Ca(2+]i that subsequently propagated in a wave-like fashion towards the center of the cell. In ventricular myocytes asynchronous Ca(2+ release signals from discrete sites with no preferential subcellular location preceded the whole-cell Ca(2+ transient. In summary, ultra-fast confocal imaging allows investigation of Ca(2+ signals with a time resolution similar to patch clamp technique, however in a less invasive fashion.

Parameter Scaling in Non-Linear Microwave Tomography

DEFF Research Database (Denmark)

Jensen, Peter Damsgaard; Rubæk, Tonny; Talcoth, Oskar

2012-01-01

Non-linear microwave tomographic imaging of the breast is a challenging computational problem. The breast is heterogeneous and contains several high-contrast and lossy regions, resulting in large differences in the measured signal levels. This implies that special care must be taken when the imag......Non-linear microwave tomographic imaging of the breast is a challenging computational problem. The breast is heterogeneous and contains several high-contrast and lossy regions, resulting in large differences in the measured signal levels. This implies that special care must be taken when...... the imaging problem is formulated. Under such conditions, microwave imaging systems will most often be considerably more sensitive to changes in the electromagnetic properties in certain regions of the breast. The result is that the parameters might not be reconstructed correctly in the less sensitive regions...... introduced as a measure of the sensitivity. The scaling of the parameters is shown to improve performance of the microwave imaging system when applied to reconstruction of images from 2-D simulated data and measurement data....

Emulation and design of terahertz reflection-mode confocal scanning microscopy based on virtual pinhole

Science.gov (United States)

Yang, Yong-fa; Li, Qi

2014-12-01

In the practical application of terahertz reflection-mode confocal scanning microscopy, the size of detector pinhole is an important factor that determines the performance of spatial resolution characteristic of the microscopic system. However, the use of physical pinhole brings some inconvenience to the experiment and the adjustment error has a great influence on the experiment result. Through reasonably selecting the parameter of matrix detector virtual pinhole (VPH), it can efficiently approximate the physical pinhole. By using this approach, the difficulty of experimental calibration is reduced significantly. In this article, an imaging scheme of terahertz reflection-mode confocal scanning microscopy that is based on the matrix detector VPH is put forward. The influence of detector pinhole size on the axial resolution of confocal scanning microscopy is emulated and analyzed. Then, the parameter of VPH is emulated when the best axial imaging performance is reached.

Optics System Design of Microwave Imaging Reflectometry for the EAST Tokamak

International Nuclear Information System (INIS)

Zhu Yilun; Zhao Zhenling; Tong Li; Chen Dongxu; Xie Jinlin; Liu Wandong

2016-01-01

A front-end optics system has been developed for the EAST microwave imaging reflectometry for 2D density fluctuation measurement. Via the transmitter optics system, a combination of eight transmitter beams with independent frequencies is employed to illuminate wide poloidal regions on eight distinct cutoff layers. The receiver optics collect the reflected wavefront and project them onto the vertical detector array with 12 antennas. Utilizing optimized Field Curvature adjustment lenses in the receiver optics, the front-end optics system provides a flexible and perfect matching between the image plane and a specified cutoff layer in the plasma, which ensures the correct data interpretation of density fluctuation measurement. (paper)

An interactive visualization tool for multi-channel confocal microscopy data in neurobiology research

KAUST Repository

Yong Wan,

2009-11-01

Confocal microscopy is widely used in neurobiology for studying the three-dimensional structure of the nervous system. Confocal image data are often multi-channel, with each channel resulting from a different fluorescent dye or fluorescent protein; one channel may have dense data, while another has sparse; and there are often structures at several spatial scales: subneuronal domains, neurons, and large groups of neurons (brain regions). Even qualitative analysis can therefore require visualization using techniques and parameters fine-tuned to a particular dataset. Despite the plethora of volume rendering techniques that have been available for many years, the techniques standardly used in neurobiological research are somewhat rudimentary, such as looking at image slices or maximal intensity projections. Thus there is a real demand from neurobiologists, and biologists in general, for a flexible visualization tool that allows interactive visualization of multi-channel confocal data, with rapid fine-tuning of parameters to reveal the three-dimensional relationships of structures of interest. Together with neurobiologists, we have designed such a tool, choosing visualization methods to suit the characteristics of confocal data and a typical biologist\\'s workflow. We use interactive volume rendering with intuitive settings for multidimensional transfer functions, multiple render modes and multi-views for multi-channel volume data, and embedding of polygon data into volume data for rendering and editing. As an example, we apply this tool to visualize confocal microscopy datasets of the developing zebrafish visual system.

Design considerations of a real-time clinical confocal microscope

Science.gov (United States)

Masters, Barry R.

1991-06-01

A real-time clinical confocal light microscope provides the ophthalmologist with a new tool for the observation of the cornea and the ocular lens. In addition, the ciliary body, the iris, and the sclera can be observed. The real-time light microscopic images have high contrast and resolution. The transverse resolution is about one half micron and the range resolution is one micron. The following observations were made with visible light: corneal epithelial cells, wing cells, basal cells, Bowman's membrane, nerve fibers, basal lamina, fibroblast nuclei, Descemet's membrane, endothelial cells. Observation of the in situ ocular lens showed lens capsule, lens epithelium, lens fibrils, the interior of lens fibrils. The applications of the confocal microscope include: eye banking, laser refractive surgery, observation of wound healing, observation of the iris, the sciera, the ciliary body, the ocular lens, and the intraocular lens. Digital image processing can produce three-dimensional reconstructions of the cornea and the ocular lens.

Detection of UV-induced pigmentary and epidermal changes over time using in vivo reflectance confocal microscopy

NARCIS (Netherlands)

Middelkamp-Hup, Maritza A.; Park, H.-Y.; Lee, Jin; Gilchrest, Barbara A.; Gonzalez, Salvador

2006-01-01

In vivo reflectance confocal microscopy (RCM) provides high-resolution optical sections of the skin in its native state, without needing to fix or section the tissue. Melanin provides an excellent contrast for RCM, giving a bright signal in the confocal images. The pigmented guinea-pig is a common

Simultaneous Microwave Imaging System for Density and Temperature Fluctuation Measurements on TEXTOR

International Nuclear Information System (INIS)

Park, H.; Mazzucato, E.; Munsat, T.; Domier, C.W.; Johnson, M.; Luhmann, N.C. Jr.; Wang, J.; Xia, Z.; Classen, I.G.J.; Donne, A.J.H.; Pol, M.J. van de

2004-01-01

Diagnostic systems for fluctuation measurements in plasmas have, of necessity, evolved from simple 1-D systems to multi-dimensional systems due to the complexity of the MHD and turbulence physics of plasmas illustrated by advanced numerical simulations. Using the recent significant advancements in millimeter wave imaging technology, Microwave Imaging Reflectometry (MIR) and Electron Cyclotron Emission Imaging (ECEI), simultaneously measuring density and temperature fluctuations, are developed for TEXTOR. The MIR system was installed on TEXTOR and the first experiment was performed in September, 2003. Subsequent MIR campaigns have yielded poloidally resolved spectra and assessments of poloidal velocity. The new 2-D ECE Imaging system (with a total of 128 channels), installed on TEXTOR in December, 2003, successfully captured a true 2-D images of Te fluctuations of m=1 oscillation (''sawteeth'') near the q ∼ 1 surface for the first time

High-resolution imaging of basal cell carcinoma: a comparison between multiphoton microscopy with fluorescence lifetime imaging and reflectance confocal microscopy.

Science.gov (United States)

Manfredini, Marco; Arginelli, Federica; Dunsby, Christopher; French, Paul; Talbot, Clifford; König, Karsten; Pellacani, Giovanni; Ponti, Giovanni; Seidenari, Stefania

2013-02-01

The aim of this study was to compare morphological aspects of basal cell carcinoma (BCC) as assessed by two different imaging methods: in vivo reflectance confocal microscopy (RCM) and multiphoton tomography with fluorescence lifetime imaging implementation (MPT-FLIM). The study comprised 16 BCCs for which a complete set of RCM and MPT-FLIM images were available. The presence of seven MPT-FLIM descriptors was evaluated. The presence of seven RCM equivalent parameters was scored in accordance to their extension. Chi-squared test with Fisher's exact test and Spearman's rank correlation coefficient were determined between MPT-FLIM scores and adjusted-RCM scores. MPT-FLIM and RCM descriptors of BCC were coupled to match the descriptors that define the same pathological structures. The comparison included: Streaming and Aligned elongated cells, Streaming with multiple directions and Double alignment, Palisading (RCM) and Palisading (MPT-FLIM), Typical tumor islands, and Cell islands surrounded by fibers, Dark silhouettes and Phantom islands, Plump bright cells and Melanophages, Vessels (RCM), and Vessels (MPT-FLIM). The parameters that were significantly correlated were Melanophages/Plump Bright Cells, Aligned elongated cells/Streaming, Double alignment/Streaming with multiple directions, and Palisading (MPT-FLIM)/Palisading (RCM). According to our data, both methods are suitable to image BCC's features. The concordance between MPT-FLIM and RCM is high, with some limitations due to the technical differences between the two devices. The hardest difficulty when comparing the images generated by the two imaging modalities is represented by their different field of view. © 2012 John Wiley & Sons A/S.

Investigation of the use of microwave image line integrated circuits for use in radiometers and other microwave devices in X-band and above

Science.gov (United States)

Knox, R. M.; Toulios, P. P.; Onoda, G. Y.

1972-01-01

Program results are described in which the use of a/high permittivity rectangular dielectric image waveguide has been investigated for use in microwave and millimeter wavelength circuits. Launchers from rectangular metal waveguide to image waveguide are described. Theoretical and experimental evaluations of the radiation from curved image waveguides are given. Measurements of attenuation due to conductor and dielectric losses, adhesives, and gaps between the dielectric waveguide and the image plane are included. Various passive components are described and evaluations given. Investigations of various techniques for fabrication of image waveguide circuits using ceramic waveguides are also presented. Program results support the evaluation of the image line approach as an advantageous method for realizing low loss integrated electronic circuits for X-band and above.

A confocal optical microscope for detection of single impurities in a bulk crystal at cryogenic temperatures.

Science.gov (United States)

Karlsson, Jenny; Rippe, Lars; Kröll, Stefan

2016-03-01

A compact sample-scanning confocal optical microscope for detection of single impurities below the surface of a bulk crystal at cryogenic temperatures is described. The sample, lens, and scanners are mounted inside a helium bath cryostat and have a footprint of only 19 × 19 mm. Wide field imaging and confocal imaging using a Blu-ray lens immersed in liquid helium are demonstrated with excitation at 370 nm. A spatial resolution of 300 nm and a detection efficiency of 1.6% were achieved.

Concurrent Reflectance Confocal Microscopy and Laser Doppler Flowmetry to Improve Skin Cancer Imaging: A Monte Carlo Model and Experimental Validation

Directory of Open Access Journals (Sweden)

Alireza Mowla

2016-09-01

Full Text Available Optical interrogation of suspicious skin lesions is standard care in the management of skin cancer worldwide. Morphological and functional markers of malignancy are often combined to improve expert human diagnostic power. We propose the evaluation of the combination of two independent optical biomarkers of skin tumours concurrently. The morphological modality of reflectance confocal microscopy (RCM is combined with the functional modality of laser Doppler flowmetry, which is capable of quantifying tissue perfusion. To realize the idea, we propose laser feedback interferometry as an implementation of RCM, which is able to detect the Doppler signal in addition to the confocal reflectance signal. Based on the proposed technique, we study numerical models of skin tissue incorporating two optical biomarkers of malignancy: (i abnormal red blood cell velocities and concentrations and (ii anomalous optical properties manifested through tissue confocal reflectance, using Monte Carlo simulation. We also conduct a laboratory experiment on a microfluidic channel containing a dynamic turbid medium, to validate the efficacy of the technique. We quantify the performance of the technique by examining a signal to background ratio (SBR in both the numerical and experimental models, and it is shown that both simulated and experimental SBRs improve consistently using this technique. This work indicates the feasibility of an optical instrument, which may have a role in enhanced imaging of skin malignancies.

Reflectance confocal microscopy: an effective tool for monitoring ultraviolet B phototherapy in psoriasis.

NARCIS (Netherlands)

Wolberink, E.A.W.; Erp, P.E.J. van; Boer-van Huizen, R.T. de; Kerkhof, P.C.M. van de; Gerritsen, M.J.P.

2012-01-01

Background In vivo reflectance confocal microscopy (RCM) is a novel, noninvasive imaging technique which enables imaging of skin at a cellular resolution comparable to conventional microscopy. Objectives We performed a pilot study to evaluate RCM as a noninvasive tool for monitoring ultraviolet (UV)

Confocal microscopy patterns in nonmelanoma skin cancer and clinical applications.

Science.gov (United States)

González, S; Sánchez, V; González-Rodríguez, A; Parrado, C; Ullrich, M

2014-06-01

Reflectance confocal microscopy is currently the most promising noninvasive diagnostic tool for studying cutaneous structures between the stratum corneum and the superficial reticular dermis. This tool gives real-time images parallel to the skin surface; the microscopic resolution is similar to that of conventional histology. Numerous studies have identified the main confocal features of various inflammatory skin diseases and tumors, demonstrating the good correlation of these features with certain dermatoscopic patterns and histologic findings. Confocal patterns and diagnostic algorithms have been shown to have high sensitivity and specificity in melanoma and nonmelanoma skin cancer. Possible present and future applications of this noninvasive technology are wide ranging and reach beyond its use in noninvasive diagnosis. This tool can also be used, for example, to evaluate dynamic skin processes that occur after UV exposure or to assess tumor response to noninvasive treatments such as photodynamic therapy. We explain the characteristic confocal features found in the main nonmelanoma skin tumors and discuss possible applications for this novel diagnostic technique in routine dermatology practice. Copyright © 2012 Elsevier España, S.L. and AEDV. All rights reserved.

Analysis of endoplasmic reticulum of tobacco cells using confocal microscopy

Czech Academy of Sciences Publication Activity Database

Radochová, Barbora; Janáček, Jiří; Schwarzerová, K.; Demjénová, E.; Tomori, Z.; Karen, Petr; Kubínová, Lucie

2005-01-01

Roč. 24, č. 11 (2005), s. 181-185 ISSN 1580-3139 R&D Projects: GA AV ČR(CZ) KJB6011309 Institutional research plan: CEZ:AV0Z50110509 Keywords : confocal microscopy * endoplasmic reticulum * image analysis Subject RIV: EA - Cell Biology

Correlative scanning electron and confocal microscopy imaging of labeled cells coated by indium-tin-oxide

KAUST Repository

Rodighiero, Simona

2015-03-22

Confocal microscopy imaging of cells allows to visualize the presence of specific antigens by using fluorescent tags or fluorescent proteins, with resolution of few hundreds of nanometers, providing their localization in a large field-of-view and the understanding of their cellular function. Conversely, in scanning electron microscopy (SEM), the surface morphology of cells is imaged down to nanometer scale using secondary electrons. Combining both imaging techniques have brought to the correlative light and electron microscopy, contributing to investigate the existing relationships between biological surface structures and functions. Furthermore, in SEM, backscattered electrons (BSE) can image local compositional differences, like those due to nanosized gold particles labeling cellular surface antigens. To perform SEM imaging of cells, they could be grown on conducting substrates, but obtaining images of limited quality. Alternatively, they could be rendered electrically conductive, coating them with a thin metal layer. However, when BSE are collected to detect gold-labeled surface antigens, heavy metals cannot be used as coating material, as they would mask the BSE signal produced by the markers. Cell surface could be then coated with a thin layer of chromium, but this results in a loss of conductivity due to the fast chromium oxidation, if the samples come in contact with air. In order to overcome these major limitations, a thin layer of indium-tin-oxide was deposited by ion-sputtering on gold-decorated HeLa cells and neurons. Indium-tin-oxide was able to provide stable electrical conductivity and preservation of the BSE signal coming from the gold-conjugated markers. © 2015 Wiley Periodicals, Inc.

2-D Fused Image Reconstruction approach for Microwave Tomography: a theoretical assessment using FDTD Model.

Science.gov (United States)

Bindu, G; Semenov, S

2013-01-01

This paper describes an efficient two-dimensional fused image reconstruction approach for Microwave Tomography (MWT). Finite Difference Time Domain (FDTD) models were created for a viable MWT experimental system having the transceivers modelled using thin wire approximation with resistive voltage sources. Born Iterative and Distorted Born Iterative methods have been employed for image reconstruction with the extremity imaging being done using a differential imaging technique. The forward solver in the imaging algorithm employs the FDTD method of solving the time domain Maxwell's equations with the regularisation parameter computed using a stochastic approach. The algorithm is tested with 10% noise inclusion and successful image reconstruction has been shown implying its robustness.

GHRSST L2P Gridded Global Subskin Sea Surface Temperature from the Tropical Rainfall Mapping Mission (TRMM) Microwave Imager (TMI) (GDS version 1)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) is a well calibrated passive microwave radiometer, similar to SSM/I, that contains lower...

Optimum Image Formation for Spaceborne Microwave Radiometer Products.

Science.gov (United States)

Long, David G; Brodzik, Mary J

2016-05-01

This paper considers some of the issues of radiometer brightness image formation and reconstruction for use in the NASA-sponsored Calibrated Passive Microwave Daily Equal-Area Scalable Earth Grid 2.0 Brightness Temperature Earth System Data Record project, which generates a multisensor multidecadal time series of high-resolution radiometer products designed to support climate studies. Two primary reconstruction algorithms are considered: the Backus-Gilbert approach and the radiometer form of the scatterometer image reconstruction (SIR) algorithm. These are compared with the conventional drop-in-the-bucket (DIB) gridded image formation approach. Tradeoff study results for the various algorithm options are presented to select optimum values for the grid resolution, the number of SIR iterations, and the BG gamma parameter. We find that although both approaches are effective in improving the spatial resolution of the surface brightness temperature estimates compared to DIB, SIR requires significantly less computation. The sensitivity of the reconstruction to the accuracy of the measurement spatial response function (MRF) is explored. The partial reconstruction of the methods can tolerate errors in the description of the sensor measurement response function, which simplifies the processing of historic sensor data for which the MRF is not known as well as modern sensors. Simulation tradeoff results are confirmed using actual data.

Fibre optic confocal imaging (FOCI) of keratinocytes, blood vessels and nerves in hairless mouse skin in vivo

Science.gov (United States)

BUSSAU, L. J.; VO, L. T.; DELANEY, P. M.; PAPWORTH, G. D.; BARKLA, D. H.; KING, R. G.

1998-01-01

Fibre optic confocal imaging (FOCI) enabled subsurface fluorescence microscopy of the skin of hairless mice in vivo. Application of acridine orange enabled imaging of the layers of the epidermis. The corneocytes of the stratum corneum, the keratinocytes in the basal layers and redundant hair follicles were visualised at depths greater than 100 μm. Cellular and nuclear membranes of keratinocytes of the skin were visualised by the use of acridine orange and DIOC5(3). Imaging of the skin after injection of FITC-dextran revealed an extensive network of blood vessels with a size range up to 20 μm. Blood cells could be seen moving through dermal vessels and the blood circulation through the dermal vascular bed was video-taped. The fluorescent dye 4-di-2-ASP showed the presence of nerves fibres around the hair follicles and subsurface blood vessels. Comparison was made between images obtained in vivo using FOCI and in vitro scanning electron microscopy and conventional histology. FOCI offers the potential to study dynamic events in vivo, such as blood flow, skin growth, nerve regeneration and many pathological processes, in ways which have not previously been possible. PMID:9643419

Recent progress on microwave imaging technology and new physics results

International Nuclear Information System (INIS)

Tobias, Benjamin; Luhmann, Neville C. Jr.; Domier, Calvin W.

2011-01-01

Techniques for visualizing turbulent flow in nature and in the laboratory have evolved over half a millennium from Leonardo da Vinci's sketches of cascading waterfalls to the advanced imaging technologies which are now pervasive in our daily lives. Advancements in millimeter wave imaging have served to usher in a new era in plasma diagnostics, characterized by ever improving 2D, and even 3D, images of complex phenomena in tokamak and stellarator plasmas. Examples at the forefront of this revolution are electron cyclotron emission imaging (ECEI) and microwave imaging reflectometry (MIR). ECEI has proved to be a powerful tool as it has provided immediate physics results following successful diagnostic installations on TEXTOR, ASDEX-U, DIII-D, and KSTAR. Recent results from the MIR system on LHD are demonstrating that this technique has the potential for comparable impact in the diagnosis of electron density fluctuations. This has motivated a recent resurgence in MIR research and development, building on a prototype system demonstrated on TEXTOR, toward the realization of combined ECEI/MIR systems on DIII-D and KSTAR for simultaneous imaging of electron temperature and density fluctuations. The systems discussed raise the standard for fusion plasma diagnostics and present a powerful new capability for the validation of theoretical models and numerical simulations. (author)

Analysis of identification of digital images from a map of cosmic microwaves

Science.gov (United States)

Skeivalas, J.; Turla, V.; Jurevicius, M.; Viselga, G.

2018-04-01

This paper discusses identification of digital images from the cosmic microwave background radiation map formed according to the data of the European Space Agency "Planck" telescope by applying covariance functions and wavelet theory. The estimates of covariance functions of two digital images or single images are calculated according to the random functions formed of the digital images in the form of pixel vectors. The estimates of pixel vectors are formed on expansion of the pixel arrays of the digital images by a single vector. When the scale of a digital image is varied, the frequencies of single-pixel color waves remain constant and the procedure for calculation of covariance functions is not affected. For identification of the images, the RGB format spectrum has been applied. The impact of RGB spectrum components and the color tensor on the estimates of covariance functions was analyzed. The identity of digital images is assessed according to the changes in the values of the correlation coefficients in a certain range of values by applying the developed computer program.

High-resolution nondestructive testing of multilayer dielectric materials using wideband microwave synthetic aperture radar imaging

Science.gov (United States)

Kim, Tae Hee; James, Robin; Narayanan, Ram M.

2017-04-01

Fiber Reinforced Polymer or Plastic (FRP) composites have been rapidly increasing in the aerospace, automotive and marine industry, and civil engineering, because these composites show superior characteristics such as outstanding strength and stiffness, low weight, as well as anti-corrosion and easy production. Generally, the advancement of materials calls for correspondingly advanced methods and technologies for inspection and failure detection during production or maintenance, especially in the area of nondestructive testing (NDT). Among numerous inspection techniques, microwave sensing methods can be effectively used for NDT of FRP composites. FRP composite materials can be produced using various structures and materials, and various defects or flaws occur due to environmental conditions encountered during operation. However, reliable, low-cost, and easy-to-operate NDT methods have not been developed and tested. FRP composites are usually produced as multilayered structures consisting of fiber plate, matrix and core. Therefore, typical defects appearing in FRP composites are disbondings, delaminations, object inclusions, and certain kinds of barely visible impact damages. In this paper, we propose a microwave NDT method, based on synthetic aperture radar (SAR) imaging algorithms, for stand-off imaging of internal delaminations. When a microwave signal is incident on a multilayer dielectric material, the reflected signal provides a good response to interfaces and transverse cracks. An electromagnetic wave model is introduced to delineate interface widths or defect depths from the reflected waves. For the purpose of numerical analysis and simulation, multilayered composite samples with various artificial defects are assumed, and their SAR images are obtained and analyzed using a variety of high-resolution wideband waveforms.

The challenge of diagnosing seborrheic keratosis by reflectance confocal microscopy.

Science.gov (United States)

Guo, A; Chen, J; Yang, C; Ding, Y; Zeng, Q; Tan, L

2018-05-24

Seborrheic keratosis (SK) is one of the most common skin tumors seen by dermatologists. It should be differentiated with many diseases, especially skin tumors. Reflectance confocal microscopy (RCM) has been applied for evaluation of SK. There are a few studies that describe the RCM of SK. The aim of the study was to find the challenge of diagnosing seborrheic keratosis by reflectance confocal microscopy. A total of 390 patients with a clinical suspicious diagnosis of seborrheic keratosis were enrolled in this study, and lesions from each patient were imaged with RCM. Thirty-seven of these patients performed a biopsy in order to be given a histological diagnosis. We retrospectively analyzed the outcomes of RCM diagnosis and histological diagnosis, and then found the RCM characteristics of biopsy-proven lesions. According to RCM images, 258 of 390 (66.2%) patients were diagnosed with SK, 97 of 390 (24.9%) patients could not be diagnosed by the dermatologist according to RCM. Of all 37 biopsied lesions, 23 were SK, 6 were actinic keratosis, 2 were basal cell carcinoma, and 2 were squamous cell carcinoma. It is challenge to diagnose seborrheic keratosis by reflectance confocal microscopy. It may due to the variable clinical and RCM appearances of SK, and limited depth of RCM. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Sensitivity and Specificity of Cardiac Tissue Discrimination Using Fiber-Optics Confocal Microscopy.

Science.gov (United States)

Huang, Chao; Sachse, Frank B; Hitchcock, Robert W; Kaza, Aditya K

2016-01-01

Disturbances of the cardiac conduction system constitute a major risk after surgical repair of complex cases of congenital heart disease. Intraoperative identification of the conduction system may reduce the incidence of these disturbances. We previously developed an approach to identify cardiac tissue types using fiber-optics confocal microscopy and extracellular fluorophores. Here, we applied this approach to investigate sensitivity and specificity of human and automated classification in discriminating images of atrial working myocardium and specialized tissue of the conduction system. Two-dimensional image sequences from atrial working myocardium and nodal tissue of isolated perfused rodent hearts were acquired using a fiber-optics confocal microscope (Leica FCM1000). We compared two methods for local application of extracellular fluorophores: topical via pipette and with a dye carrier. Eight blinded examiners evaluated 162 randomly selected images of atrial working myocardium (n = 81) and nodal tissue (n = 81). In addition, we evaluated the images using automated classification. Blinded examiners achieved a sensitivity and specificity of 99.2 ± 0.3% and 98.0 ± 0.7%, respectively, with the dye carrier method of dye application. Sensitivity and specificity was similar for dye application via a pipette (99.2 ± 0.3% and 94.0 ± 2.4%, respectively). Sensitivity and specificity for automated methods of tissue discrimination were similarly high. Human and automated classification achieved high sensitivity and specificity in discriminating atrial working myocardium and nodal tissue. We suggest that our findings facilitate clinical translation of fiber-optics confocal microscopy as an intraoperative imaging modality to reduce the incidence of conduction disturbances during surgical correction of congenital heart disease.

Characterization of tissue autofluorescence in Barrett's esophagus by confocal fluorescence microscopy

NARCIS (Netherlands)

Kara, M. A.; DaCosta, R. S.; Streutker, C. J.; Marcon, N. E.; Bergman, J. J. G. H. M.; Wilson, B. C.

2007-01-01

High grade dysplasia and early cancer in Barrett's esophagus can be distinguished in vivo by endoscopic autofluorescence point spectroscopy and imaging from non-dysplastic Barrett's mucosa. We used confocal fluorescence microscopy for ex vivo comparison of autofluorescence in non-dysplastic and

Probing the local microwave properties of superconducting thin films by a scanning microwave near-field microscope

CERN Document Server

Wu, L Y; Wang, K L; Jiang, T; Kang, L; Yang, S Z; Wu, P H

2002-01-01

In this paper, we present our approach to probe the local microwave properties of superconducting thin films by using the microwave near-field scanning technique. We have employed a coaxial cavity together with a niobium tip as the probe and established a scanning sample stage cooled by liquid nitrogen to study thin film devices at low temperature in our scanning microwave near-field microscope. Nondestructive images have been obtained on the inhomogeneity of the YBaCuO superconducting thin films at microwave frequency. We believe that these results would be helpful in evaluating the microwave performance of the devices.

Confocal stereology: an efficient tool for measurement of microscopic structures

Czech Academy of Sciences Publication Activity Database

Kubínová, Lucie; Janáček, Jiří

2015-01-01

Roč. 360, č. 1 (2015), s. 13-28 ISSN 0302-766X R&D Projects: GA MŠk(CZ) LH13028 Institutional support: RVO:67985823 Keywords : 3-D images * confocal microscopy * geometrical characteristics * spatial probes * stereology Subject RIV: EA - Cell Biology Impact factor: 2.948, year: 2015

Confocal soft X-ray scanning transmission microscopy: setup, alignment procedure and limitations

International Nuclear Information System (INIS)

Späth, Andreas; Raabe, Jörg; Fink, Rainer H.

2015-01-01

A conventional STXM setup has been upgraded with a second micro zone plate and aligned to confocal geometry. Two confocal geometries (in-line and off-axis) have been evaluated and a discussion on prospects and limitations is presented. Zone-plate-based scanning transmission soft X-ray microspectroscopy (STXM) is a well established technique for high-contrast imaging of sufficiently transparent specimens (e.g. ultrathin biological tissues, polymer materials, archaeometric specimens or magnetic thin films) with spatial resolutions in the regime of 20 nm and high spectroscopic or chemical sensitivity. However, due to the relatively large depth of focus of zone plates, the resolution of STXM along the optical axis so far stays unambiguously behind for thicker X-ray transparent specimens. This challenge can be addressed by the implementation of a second zone plate in the detection pathway of the beam, resulting in a confocal arrangement. Within this paper a first proof-of-principle study for a confocal STXM (cSTXM) and an elaborate alignment procedure in transmission and fluorescence geometry are presented. Based on first confocal soft X-ray micrographs of well known specimens, the advantage and limitation of cSTXM as well as further development potentials for future applications are discussed

Confocal soft X-ray scanning transmission microscopy: setup, alignment procedure and limitations

Energy Technology Data Exchange (ETDEWEB)

Späth, Andreas [Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Egerlandstraße 3, 91058 Erlangen (Germany); Raabe, Jörg [Paul Scherrer Institut, 5232 Villigen (Switzerland); Fink, Rainer H., E-mail: rainer.fink@fau.de [Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Egerlandstraße 3, 91058 Erlangen (Germany); Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Egerlandstraße 3, 91058 Erlangen (Germany)

2015-01-01

A conventional STXM setup has been upgraded with a second micro zone plate and aligned to confocal geometry. Two confocal geometries (in-line and off-axis) have been evaluated and a discussion on prospects and limitations is presented. Zone-plate-based scanning transmission soft X-ray microspectroscopy (STXM) is a well established technique for high-contrast imaging of sufficiently transparent specimens (e.g. ultrathin biological tissues, polymer materials, archaeometric specimens or magnetic thin films) with spatial resolutions in the regime of 20 nm and high spectroscopic or chemical sensitivity. However, due to the relatively large depth of focus of zone plates, the resolution of STXM along the optical axis so far stays unambiguously behind for thicker X-ray transparent specimens. This challenge can be addressed by the implementation of a second zone plate in the detection pathway of the beam, resulting in a confocal arrangement. Within this paper a first proof-of-principle study for a confocal STXM (cSTXM) and an elaborate alignment procedure in transmission and fluorescence geometry are presented. Based on first confocal soft X-ray micrographs of well known specimens, the advantage and limitation of cSTXM as well as further development potentials for future applications are discussed.

In vivo microwave-based thermoacoustic tomography of rats (Conference Presentation)

Science.gov (United States)

Lin, Li; Zhou, Yong; Wang, Lihong V.

2016-03-01

Microwave-based thermoacoustic tomography (TAT), based on the measurement of ultrasonic waves induced by microwave pulses, can reveal tissue dielectric properties that may be closely related to the physiological and pathological status of the tissues. Using microwaves as the excitation source improved imaging depth because of their deep penetration into biological tissues. We demonstrate, for the first time, in vivo microwave-based thermoacoustic imaging in rats. The transducer is rotated around the rat in a full circle, providing a full two-dimensional view. Instead of a flat ultrasonic transducer, we used a virtual line detector based on a cylindrically focused transducer. A 3 GHz microwave source with 0.6 µs pulse width and an electromagnetically shielded transducer with 2.25 MHz central frequency provided clear cross-sectional images of the rat's body. The high imaging contrast, based on the tissue's rate of absorption, and the ultrasonically defined spatial resolution combine to reveal the spine, kidney, muscle, and other deeply seated anatomical features in the rat's abdominal cavity. This non-invasive and non-ionizing imaging modality achieved an imaging depth beyond 6 cm in the rat's tissue. Cancer diagnosis based on information about tissue properties from microwave band TAT can potentially be more accurate than has previously been achievable.

In vivo near-infrared dual-axis confocal microendoscopy in the human lower gastrointestinal tract

Science.gov (United States)

Piyawattanametha, Wibool; Ra, Hyejun; Qiu, Zhen; Friedland, Shai; Liu, Jonathan T. C.; Loewke, Kevin; Kino, Gordon S.; Solgaard, Olav; Wang, Thomas D.; Mandella, Michael J.; Contag, Christopher H.

2012-02-01

Near-infrared confocal microendoscopy is a promising technique for deep in vivo imaging of tissues and can generate high-resolution cross-sectional images at the micron-scale. We demonstrate the use of a dual-axis confocal (DAC) near-infrared fluorescence microendoscope with a 5.5-mm outer diameter for obtaining clinical images of human colorectal mucosa. High-speed two-dimensional en face scanning was achieved through a microelectromechanical systems (MEMS) scanner while a micromotor was used for adjusting the axial focus. In vivo images of human patients are collected at 5 frames/sec with a field of view of 362×212 μm2 and a maximum imaging depth of 140 μm. During routine endoscopy, indocyanine green (ICG) was topically applied a nonspecific optical contrasting agent to regions of the human colon. The DAC microendoscope was then used to obtain microanatomic images of the mucosa by detecting near-infrared fluorescence from ICG. These results suggest that DAC microendoscopy may have utility for visualizing the anatomical and, perhaps, functional changes associated with colorectal pathology for the early detection of colorectal cancer.

Precision automation of cell type classification and sub-cellular fluorescence quantification from laser scanning confocal images

Directory of Open Access Journals (Sweden)

Hardy Craig Hall

2016-02-01

Full Text Available While novel whole-plant phenotyping technologies have been successfully implemented into functional genomics and breeding programs, the potential of automated phenotyping with cellular resolution is largely unexploited. Laser scanning confocal microscopy has the potential to close this gap by providing spatially highly resolved images containing anatomic as well as chemical information on a subcellular basis. However, in the absence of automated methods, the assessment of the spatial patterns and abundance of fluorescent markers with subcellular resolution is still largely qualitative and time-consuming. Recent advances in image acquisition and analysis, coupled with improvements in microprocessor performance, have brought such automated methods within reach, so that information from thousands of cells per image for hundreds of images may be derived in an experimentally convenient time-frame. Here, we present a MATLAB-based analytical pipeline to 1 segment radial plant organs into individual cells, 2 classify cells into cell type categories based upon random forest classification, 3 divide each cell into sub-regions, and 4 quantify fluorescence intensity to a subcellular degree of precision for a separate fluorescence channel. In this research advance, we demonstrate the precision of this analytical process for the relatively complex tissues of Arabidopsis hypocotyls at various stages of development. High speed and robustness make our approach suitable for phenotyping of large collections of stem-like material and other tissue types.

Classifying distinct basal cell carcinoma subtype by means of dermatoscopy and reflectance confocal microscopy.

Science.gov (United States)

Longo, Caterina; Lallas, Aimilios; Kyrgidis, Athanassios; Rabinovitz, Harold; Moscarella, Elvira; Ciardo, Silvana; Zalaudek, Iris; Oliviero, Margaret; Losi, Amanda; Gonzalez, Salvador; Guitera, Pascale; Piana, Simonetta; Argenziano, Giuseppe; Pellacani, Giovanni

2014-10-01

The current guidelines for the management of basal cell carcinoma (BCC) suggest a different therapeutic approach according to histopathologic subtype. Although dermatoscopic and confocal criteria of BCC have been investigated, no specific studies were performed to evaluate the distinct reflectance confocal microscopy (RCM) aspects of BCC subtypes. To define the specific dermatoscopic and confocal criteria for delineating different BCC subtypes. Dermatoscopic and confocal images of histopathologically confirmed BCCs were retrospectively evaluated for the presence of predefined criteria. Frequencies of dermatoscopic and confocal parameters are provided. Univariate and adjusted odds ratios were calculated. Discriminant analyses were performed to define the independent confocal criteria for distinct BCC subtypes. Eighty-eight BCCs were included. Dermatoscopically, superficial BCCs (n=44) were primarily typified by the presence of fine telangiectasia, multiple erosions, leaf-like structures, and revealed cords connected to the epidermis and epidermal streaming upon RCM. Nodular BCCs (n=22) featured the classic dermatoscopic features and well outlined large basaloid islands upon RCM. Infiltrative BCCs (n=22) featured structureless, shiny red areas, fine telangiectasia, and arborizing vessels on dermatoscopy and dark silhouettes upon RCM. The retrospective design. Dermatoscopy and confocal microscopy can reliably classify different BCC subtypes. Copyright © 2014 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

In vivo imaging of induction of heat-shock protein-70 gene expression with fluorescence reflectance imaging and intravital confocal microscopy following brain ischaemia in reporter mice.

Science.gov (United States)

de la Rosa, Xavier; Santalucía, Tomàs; Fortin, Pierre-Yves; Purroy, Jesús; Calvo, Maria; Salas-Perdomo, Angélica; Justicia, Carles; Couillaud, Franck; Planas, Anna M

2013-02-01

Stroke induces strong expression of the 72-kDa heat-shock protein (HSP-70) in the ischaemic brain, and neuronal expression of HSP-70 is associated with the ischaemic penumbra. The aim of this study was to image induction of Hsp-70 gene expression in vivo after brain ischaemia using reporter mice. A genomic DNA sequence of the Hspa1b promoter was used to generate an Hsp70-mPlum far-red fluorescence reporter vector. The construct was tested in cellular systems (NIH3T3 mouse fibroblast cell line) by transient transfection and examining mPlum and Hsp-70 induction under a challenge. After construct validation, mPlum transgenic mice were generated. Focal brain ischaemia was induced by transient intraluminal occlusion of the middle cerebral artery and the mice were imaged in vivo with fluorescence reflectance imaging (FRI) with an intact skull, and with confocal microscopy after opening a cranial window. Cells transfected with the Hsp70-mPlum construct showed mPlum fluorescence after stimulation. One day after induction of ischaemia, reporter mice showed a FRI signal located in the HSP-70-positive zone within the ipsilateral hemisphere, as validated by immunohistochemistry. Live confocal microscopy allowed brain tissue to be visualized at the cellular level. mPlum fluorescence was observed in vivo in the ipsilateral cortex 1 day after induction of ischaemia in neurons, where it is compatible with penumbra and neuronal viability, and in blood vessels in the core of the infarction. This study showed in vivo induction of Hsp-70 gene expression in ischaemic brain using reporter mice. The fluorescence signal showed in vivo the induction of Hsp-70 in penumbra neurons and in the vasculature within the ischaemic core.

Confocal endomicroscopy: Is it time to move on?

Science.gov (United States)

Robles-Medranda, Carlos

2016-01-10

Confocal laser endomicroscopy permits in-vivo microscopy evaluation during endoscopy procedures. It can be used in all the parts of the gastrointestinal tract and includes: Esophagus, stomach, small bowel, colon, biliary tract through and endoscopic retrograde cholangiopancreatography and pancreas through needles during endoscopic ultrasound procedures. Many researches demonstrated a high correlation of results between confocal laser endomicroscopy and histopathology in the diagnosis of gastrointestinal lesions; with accuracy in about 86% to 96%. Moreover, in spite that histopathology remains the gold-standard technique for final diagnosis of any diseases; a considerable number of misdiagnosis rate could be present due to many factors such as interpretation mistakes, biopsy site inaccuracy, or number of biopsies. Theoretically; with the diagnostic accuracy rates of confocal laser endomicroscopy could help in a daily practice to improve diagnosis and treatment management of the patients. However, it is still not routinely used in the clinical practice due to many factors such as cost of the procedure, lack of codification and reimbursement in some countries, absence of standard of care indications, availability, physician image-interpretation training, medico-legal problems, and the role of the pathologist. These limitations are relative, and solutions could be found based on new researches focused to solve these barriers.

Simple method for sub-diffraction resolution imaging of cellular structures on standard confocal microscopes by three-photon absorption of quantum dots.

Directory of Open Access Journals (Sweden)

Anje Sporbert

Full Text Available This study describes a simple technique that improves a recently developed 3D sub-diffraction imaging method based on three-photon absorption of commercially available quantum dots. The method combines imaging of biological samples via tri-exciton generation in quantum dots with deconvolution and spectral multiplexing, resulting in a novel approach for multi-color imaging of even thick biological samples at a 1.4 to 1.9-fold better spatial resolution. This approach is realized on a conventional confocal microscope equipped with standard continuous-wave lasers. We demonstrate the potential of multi-color tri-exciton imaging of quantum dots combined with deconvolution on viral vesicles in lentivirally transduced cells as well as intermediate filaments in three-dimensional clusters of mouse-derived neural stem cells (neurospheres and dense microtubuli arrays in myotubes formed by stacks of differentiated C2C12 myoblasts.

Portable Wideband Microwave Imaging System for Intracranial Hemorrhage Detection Using Improved Back-projection Algorithm with Model of Effective Head Permittivity

Science.gov (United States)

Mobashsher, Ahmed Toaha; Mahmoud, A.; Abbosh, A. M.

2016-02-01

Intracranial hemorrhage is a medical emergency that requires rapid detection and medication to restrict any brain damage to minimal. Here, an effective wideband microwave head imaging system for on-the-spot detection of intracranial hemorrhage is presented. The operation of the system relies on the dielectric contrast between healthy brain tissues and a hemorrhage that causes a strong microwave scattering. The system uses a compact sensing antenna, which has an ultra-wideband operation with directional radiation, and a portable, compact microwave transceiver for signal transmission and data acquisition. The collected data is processed to create a clear image of the brain using an improved back projection algorithm, which is based on a novel effective head permittivity model. The system is verified in realistic simulation and experimental environments using anatomically and electrically realistic human head phantoms. Quantitative and qualitative comparisons between the images from the proposed and existing algorithms demonstrate significant improvements in detection and localization accuracy. The radiation and thermal safety of the system are examined and verified. Initial human tests are conducted on healthy subjects with different head sizes. The reconstructed images are statistically analyzed and absence of false positive results indicate the efficacy of the proposed system in future preclinical trials.

Assessment of nerve ultrastructure by fibre-optic confocal microscopy.

Science.gov (United States)

Cushway, T R; Lanzetta, M; Cox, G; Trickett, R; Owen, E R

1996-01-01

Fibre-optic technology combined with confocality produces a microscope capable of optical thin sectioning. In this original study, tibial nerves have been stained in a rat model with a vital dye, 4-(4-diethylaminostyryl)-N-methylpyridinium iodide, and analysed by fibre-optic confocal microscopy to produce detailed images of nerve ultrastructure. Schwann cells, nodes of Ranvier and longitudinal myelinated sheaths enclosing axons were clearly visible. Single axons appeared as brightly staining longitudinal structures. This allowed easy tracing of multiple signal axons within the nerve tissue. An accurate measurement of internodal lengths was easily accomplished. This technique is comparable to current histological techniques, but does not require biopsy, thin sectioning or tissue fixing. This study offers a standard for further in vivo microscopy, including the possibility of monitoring the progression of nerve regeneration following microsurgical neurorraphy.

A Directional Antenna in a Matching Liquid for Microwave Radar Imaging

Directory of Open Access Journals (Sweden)

Saeed I. Latif

2015-01-01

Full Text Available The detailed design equations and antenna parameters for a directional antenna for breast imaging are presented in this paper. The antenna was designed so that it could be immersed in canola oil to achieve efficient coupling of the electromagnetic energy to the breast tissue. Ridges were used in the horn antenna to increase the operating bandwidth. The antenna has an exponentially tapered section for impedance matching. The double-ridged horn antenna has a wideband performance from 1.5 GHz to 5 GHz (3.75 GHz or 110% of impedance bandwidth, which is suitable for breast microwave radar imaging. The fabricated antenna was tested and compared with simulated results, and similar bandwidths were obtained. Experiments were conducted on breast phantoms using these antennas, to detect a simulated breast lesion. The reconstructed image from the experiments shows distinguishable tumor responses indicating promising results for successful breast cancer detection.

Confocal detection of Rayleigh scattering for residual stress measurement in chemically tempered glass

Energy Technology Data Exchange (ETDEWEB)

Hödemann, S., E-mail: siim.hodemann@ut.ee; Möls, P.; Kiisk, V.; Saar, R.; Kikas, J. [Institute of Physics, University of Tartu, Wilhelm Ostwald st., Tartu 50411 (Estonia); Murata, T. [Nippon Electric Glass Co., 7-1 Seiran 2-chome, Otsu-shi, Shiga 520-8639 (Japan)

2015-12-28

A new optical method is presented for evaluation of the stress profile in chemically tempered (chemically strengthened) glass based on confocal detection of scattered laser beam. Theoretically, a lateral resolution of 0.2 μm and a depth resolution of 0.6 μm could be achieved by using a confocal microscope with high-NA immersion objective. The stress profile in the 250 μm thick surface layer of chemically tempered lithium aluminosilicate glass was measured with a high spatial resolution to illustrate the capability of the method. The confocal method is validated using transmission photoelastic and Na{sup +} ion concentration profile measurement. Compositional influence on the stress-optic coefficient is calculated and discussed. Our method opens up new possibilities for three-dimensional scattered light tomography of mechanical imaging in birefringent materials.

Confocal Endomicroscopy of Colorectal Polyps

Directory of Open Access Journals (Sweden)

Vivian M. Ussui

2012-01-01

Full Text Available Confocal laser endomicroscopy (CLE is one of several novel methods that provide real-time, high-resolution imaging at a micron scale via endoscopes. CLE has the potential to be a disruptive technology in that it can change the current algorithms that depend on biopsy to perform surveillance of high-risk conditions. Furthermore, it allows on-table decision making that has the potential to guide therapy in real time and reduce the need for repeated procedures. CLE and related technologies are often termed “virtual biopsy” as they simulate the images seen in traditional histology. However, the imaging of living tissue allows more than just pragmatic convenience; it also allows imaging of living tissue such as active capillary circulation, cellular death, and vascular and endothelial translocation, thus extending beyond what is capable in traditional biopsy. Immediate potential applications of CLE are to guide biopsy sampling in Barrett's esophagus and inflammatory bowel disease surveillance, evaluation of colorectal polyps, and intraductal imaging of the pancreas and bile duct. Data on these applications is rapidly emerging, and more is needed to clearly demonstrate the optimal applications of CLE. In this paper, we will focus on the role of CLE as applied to colorectal polyps detected during colonoscopy.

Microwave Photonic Imaging Radiometer, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Passive Microwave Remote Sensing is currently utilized by NASA, NOAA, and USGIS to conduct Earth Science missions, including weather forecasting, early warning...

A multi-axis confocal rheoscope for studying shear flow of structured fluids

KAUST Repository

Lin, Neil Y. C.; McCoy, Jonathan H.; Cheng, Xiang; Leahy, Brian; Israelachvili, Jacob N.; Cohen, Itai

2014-01-01

of confinement effects. By using our shear cell in conjunction with a biaxial force measurement device and a high-speed confocal microscope, we are able to measure the real-time biaxial stress while simultaneously imaging the material three-dimensional structure

Multicolor probe-based confocal laser endomicroscopy: a new world for in vivo and real-time cellular imaging

Science.gov (United States)

Vercauteren, Tom; Doussoux, François; Cazaux, Matthieu; Schmid, Guillaume; Linard, Nicolas; Durin, Marie-Amélie; Gharbi, Hédi; Lacombe, François

2013-03-01

Since its inception in the field of in vivo imaging, endomicroscopy through optical fiber bundles, or probe-based Confocal Laser Endomicroscopy (pCLE), has extensively proven the benefit of in situ and real-time examination of living tissues at the microscopic scale. By continuously increasing image quality, reducing invasiveness and improving system ergonomics, Mauna Kea Technologies has turned pCLE not only into an irreplaceable research instrument for small animal imaging, but also into an accurate clinical decision making tool with applications as diverse as gastrointestinal endoscopy, pulmonology and urology. The current implementation of pCLE relies on a single fluorescence spectral band making different sources of in vivo information challenging to distinguish. Extending the pCLE approach to multi-color endomicroscopy therefore appears as a natural plan. Coupling simultaneous multi-laser excitation with minimally invasive, microscopic resolution, thin and flexible optics, allows the fusion of complementary and valuable biological information, thus paving the way to a combination of morphological and functional imaging. This paper will detail the architecture of a new system, Cellvizio Dual Band, capable of video rate in vivo and in situ multi-spectral fluorescence imaging with a microscopic resolution. In its standard configuration, the system simultaneously operates at 488 and 660 nm, where it automatically performs the necessary spectral, photometric and geometric calibrations to provide unambiguously co-registered images in real-time. The main hardware and software features, including calibration procedures and sub-micron registration algorithms, will be presented as well as a panorama of its current applications, illustrated with recent results in the field of pre-clinical imaging.

Characterization of hydrogel microstructure using laser tweezers particle tracking and confocal reflection imaging

International Nuclear Information System (INIS)

Kotlarchyk, M A; Botvinick, E L; Putnam, A J

2010-01-01

Hydrogels are commonly used as extracellular matrix mimetics for applications in tissue engineering and increasingly as cell culture platforms with which to study the influence of biophysical and biochemical cues on cell function in 3D. In recent years, a significant number of studies have focused on linking substrate mechanical properties to cell function using standard methodologies to characterize the bulk mechanical properties of the hydrogel substrates. However, current understanding of the correlations between the microstructural mechanical properties of hydrogels and cell function in 3D is poor, in part because of a lack of appropriate techniques. Here we have utilized a laser tracking system, based on passive optical microrheology instrumentation, to characterize the microstructure of viscoelastic fibrin clots. Trajectories and mean square displacements were observed as bioinert PEGylated (PEG: polyethylene glycol) microspheres (1, 2 or 4.7 μm in diameter) diffused within confined pores created by the protein phase of fibrin hydrogels. Complementary confocal reflection imaging revealed microstructures comprised of a highly heterogeneous fibrin network with a wide range of pore sizes. As the protein concentration of fibrin gels was increased, our quantitative laser tracking measurements showed a corresponding decrease in particle mean square displacements with greater resolution and sensitivity than conventional imaging techniques. This platform-independent method will enable a more complete understanding of how changes in substrate mechanical properties simultaneously influence other microenvironmental parameters in 3D cultures.

Three-dimensional computer reconstruction of large tissue volumes based on composing series of high-resolution confocal images by GlueMRC and LinkMRC software

Czech Academy of Sciences Publication Activity Database

Karen, Petr; Jirkovská, M.; Tomori, Z.; Demjénová, E.; Janáček, Jiří; Kubínová, Lucie

2003-01-01

Roč. 62, č. 5 (2003), s. 415-422 ISSN 1059-910X R&D Projects: GA ČR GA304/01/0257 Grant - others:VEGA(SK) 2/1146/21; CZ-SK GA MŠk(CZ) KONTAKT 126/184 Institutional research plan: CEZ:AV0Z5011922 Keywords : 3D reconstruction * confocal microscopy * image processing Subject RIV: JC - Computer Hardware ; Software Impact factor: 2.307, year: 2003

Thermoacoustic Imaging and Therapy Guidance based on Ultra-short Pulsed Microwave Pumped Thermoelastic Effect Induced with Superparamagnetic Iron Oxide Nanoparticles.

Science.gov (United States)

Wen, Liewei; Yang, Sihua; Zhong, Junping; Zhou, Quan; Xing, Da

2017-01-01

Multifunctional nanoparticle-mediated imaging and therapeutic techniques are promising modalities for accurate localization and targeted treatment of cancer in clinical settings. Thermoacoustic (TA) imaging is highly sensitive to detect the distribution of water, ions or specific nanoprobes and provides excellent resolution, good contrast and superior tissue penetrability. TA therapy is a potential non-invasive approach for the treatment of deep-seated tumors. In this study, human serum albumin (HSA)-functionalized superparamagnetic iron oxide nanoparticle (HSA-SPIO) is used as a multifunctional nanoprobe with clinical application potential for MRI, TA imaging and treatment of tumor. In addition to be a MRI contrast agent for tumor localization, HSA-SPIO can absorb pulsed microwave energy and transform it into shockwave via the thermoelastic effect. Thereby, the reconstructed TA image by detecting TA signal is expected to be a sensitive and accurate representation of the HSA-SPIO accumulation in tumor. More importantly, owing to the selective retention of HSA-SPIO in tumor tissues and strong TA shockwave at the cellular level, HSA-SPIO induced TA effect under microwave-pulse radiation can be used to highly-efficiently kill cancer cells and inhibit tumor growth. Furthermore, ultra-short pulsed microwave with high excitation efficiency and deep penetrability in biological tissues makes TA therapy a highly-efficient anti-tumor modality on the versatile platform. Overall, HSA-SPIO mediated MRI and TA imaging would offer more comprehensive diagnostic information and enable dynamic visualization of nanoagents in the tumorous tissue thereby tumor-targeted therapy.

The Soil Moisture Dependence of TRMM Microwave Imager Rainfall Estimates

Science.gov (United States)

Seyyedi, H.; Anagnostou, E. N.

2011-12-01

This study presents an in-depth analysis of the dependence of overland rainfall estimates from the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) on the soil moisture conditions at the land surface. TMI retrievals are verified against rainfall fields derived from a high resolution rain-gauge network (MESONET) covering Oklahoma. Soil moisture (SOM) patterns are extracted based on recorded data from 2000-2007 with 30 minutes temporal resolution. The area is divided into wet and dry regions based on normalized SOM (Nsom) values. Statistical comparison between two groups is conducted based on recorded ground station measurements and the corresponding passive microwave retrievals from TMI overpasses at the respective MESONET station location and time. The zero order error statistics show that the Probability of Detection (POD) for the wet regions (higher Nsom values) is higher than the dry regions. The Falls Alarm Ratio (FAR) and volumetric FAR is lower for the wet regions. The volumetric missed rain for the wet region is lower than dry region. Analysis of the MESONET-to-TMI ratio values shows that TMI tends to overestimate for surface rainfall intensities less than 12 (mm/h), however the magnitude of the overestimation over the wet regions is lower than the dry regions.

Current Operational Use of and Future Needs for Microwave Imagery at NOAA

Science.gov (United States)

Goldberg, M.; McWilliams, G.; Chang, P.

2017-12-01

There are many applications of microwave imagery served by NOAA's operational products and services. They include the use of microwave imagery and derived products for monitoring precipitation, tropical cyclones, sea surface temperature under all weather conditions, wind speed, snow and ice cover, and even soil moisture. All of NOAA's line offices including the National Weather Service, National Ocean Service, National Marine Fisheries Service, and Office of Oceanic and Atmospheric Research rely on microwave imagery. Currently microwave imagery products used by NOAA come from a constellation of satellites that includes Air Force's Special Sensor Microwave Imager Sounder (SSMIS), the Japanese Advanced Microwave Scanning Radiometer (AMSR), the Navy's WindSat, and NASA's Global Precipitation Monitoring (GPM) Microwave Imager (GMI). Follow-on missions for SSMIS are very uncertain, JAXA approval for a follow-on to AMSR2 is still pending, and GMI is a research satellite (lacking high-latitude coverage) with no commitment for operational continuity. Operational continuity refers to a series of satellites, so when one satellite reaches its design life a new satellite is launched. EUMETSAT has made a commitment to fly a microwave imager in the mid-morning orbit. China and Russia have demonstrated on-orbit microwave imagers. Of utmost importance to NOAA, however, is the quality, access, and latency of the data This presentation will focus on NOAA's current requirements for microwave imagery data which, for the most part, are being fulfilled by AMSR2, SSMIS, and WindSat. It will include examples of products and applications of microwave imagery at NOAA. We will also discuss future needs, especially for improved temporal resolution which hopefully can be met by an international constellation of microwave imagers. Finally, we will discuss what we are doing to address the potential gap in imagery.

Confocal microscopy studies of morphology and apoptosis: ovaries, limbs, embryos and insects

Science.gov (United States)

Confocal laser scanning microscopy (CLSM) is a technique that is capable of generating serial sections of whole-mount tissue and then reassembling the computer-stored images as a virtual 3-dimensional structure. In many ways CLSM offers an alternative to traditional sectioning ap...

Confocal scanning microscopy

DEFF Research Database (Denmark)

Bariani, Paolo

This report is based on a metrological investigation on confocal microscopy technique carried out by Uffe Rolf Arlø Theilade and Paolo Bariani. The purpose of the experimental activity was twofold a metrological instrument characterization and application to assessment of rough PP injection moulded...... replicated topography. Confocal microscopy is seen to be a promising technique in metrology of microstructures. Some limitations with respect to surface metrology were found during the experiments. The experiments were carried out using a Zeiss LSM 5 Pascal microscope owned by the Danish Polymer Centre...

Development of a multi-channel horn mixer array for microwave imaging plasma diagnostics

International Nuclear Information System (INIS)

Ito, Naoki; Kuwahara, Daisuke; Nagayama, Yoshio

2015-01-01

Microwave to millimeter-wave diagnostics techniques, such as interferometry, reflectometry, scattering, and radiometry, have been powerful tools for diagnosing magnetically confined plasmas. The resultant measurements have clarified several physics issues, including instability, wave phenomena, and fluctuation-induced transport. Electron cyclotron emission imaging has been an important tool in the investigation of temperature fluctuations, while reflectometry has been employed to measure plasma density profiles and their fluctuations. We have developed a horn-antenna mixer array (HMA), a 50 - 110 GHz 1D antenna array, which can be easily stacked as a 2D array. This article describes an upgrade to the horn mixer array that combines well-characterized mixers, waveguide-to-microstrip line transitions, intermediate frequency amplifiers, and internal local oscillator modules using a monolithic microwave integrated circuit technology to improve system performance. We also report on the use of a multi-channel HMA system. (author)

Confocal laser feedback tomography for skin cancer detection.

Science.gov (United States)

Mowla, Alireza; Du, Benjamin Wensheng; Taimre, Thomas; Bertling, Karl; Wilson, Stephen; Soyer, H Peter; Rakić, Aleksandar D

2017-09-01

Tomographic imaging of soft tissue such as skin has a potential role in cancer detection. The penetration of infrared wavelengths makes a confocal approach based on laser feedback interferometry feasible. We present a compact system using a semiconductor laser as both transmitter and receiver. Numerical and physical models based on the known optical properties of keratinocyte cancers were developed. We validated the technique on three phantoms containing macro-structural changes in optical properties. Experimental results were in agreement with numerical simulations and structural changes were evident which would permit discrimination of healthy tissue and tumour. Furthermore, cancer type discrimination was also able to be visualized using this imaging technique.

GHRSST Level 2P Regional Subskin Sea Surface Temperature from the Tropical Rainfall Mapping Mission (TRMM) Microwave Imager (TMI) for the Atlantic Ocean (GDS version 1)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) is a well calibrated passive microwave radiometer, similar to SSM/I, that contains lower...

Tapping mode microwave impedance microscopy

KAUST Repository

Lai, K.

2009-01-01

We report tapping mode microwave impedance imaging based on atomic force microscope platforms. The shielded cantilever probe is critical to localize the tip-sample interaction near the tip apex. The modulated tip-sample impedance can be accurately simulated by the finite-element analysis and the result agrees quantitatively to the experimental data on a series of thin-film dielectric samples. The tapping mode microwave imaging is also superior to the contact mode in that the thermal drift in a long time scale is totally eliminated and an absolute measurement on the dielectric properties is possible. We demonstrated tapping images on working nanodevices, and the data are consistent with the transport results. © 2009 American Institute of Physics.

Stratified spherical model for microwave imaging of the brain: Analysis and experimental validation of transmitted power

DEFF Research Database (Denmark)

Bjelogrlic, Mina; Volery, Maxime; Fuchs, Benjamin

2018-01-01

This work presents the analysis of power transmission of a radiating field inside the human head for microwave imaging applications. For this purpose, a spherical layered model composed of dispersive biological tissues is investigated in the range of (0.5–4) GHz and is confronted to experimental ...

GHRSST Level 2P Global Subskin Sea Surface Temperature from TRMM Microwave Imager (TMI) onboard Tropical Rainfall Measurement Mission (TRMM) satellite (GDS versions 1 and 2)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — GDS2 Version -The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) is a well calibrated passive microwave radiometer, similar to the Special Sensor...

Assessing Radiometric Stability of the 17-Plus-Year TRMM Microwave Imager 1B11 Version-8 (GPM05 Brightness Temperature Product

Directory of Open Access Journals (Sweden)

Ruiyao Chen

2017-12-01

Full Text Available The NASA Tropical Rainfall Measuring Mission (TRMM Microwave Imager (TMI has produced a 17-plus-year time-series of calibrated microwave radiances that have remarkable value for investigating the effects of the Earth’s climate change over the tropics. Recently, the Global Precipitation Measurement (GPM Inter-Satellite Radiometric Calibration (XCAL Working Group have performed various calibration and corrections that yielded the legacy TMI 1B11 Version 8 (also called GPM05 brightness temperature product, which will be released in late 2017 by the NASA Precipitation Processing System. Since TMI served as the radiometric transfer standard for the TRMM constellation microwave radiometer sensors, it is important to document its accuracy. In this paper, the various improvements applied to TMI 1B11 V8 are summarized, and the radiometric calibration stability is evaluated by comparisons with a radiative transfer model and by XCAL evaluations with the Global Precipitation Measuring Microwave Imager during their 13-month overlap period. Evaluation methods will be described and results will be presented, which demonstrate that TMI has achieved a radiometric stability level of a few deciKelvin over almost two decades.

An FFT-based Method for Attenuation Correction in Fluorescence Confocal Microscopy

NARCIS (Netherlands)

Roerdink, J.B.T.M.; Bakker, M.

1993-01-01

A problem in three-dimensional imaging by a confocal scanning laser microscope (CSLM) in the (epi)fluorescence mode is the darkening of the deeper layers due to absorption and scattering of both the excitation and the fluorescence light. In this paper we propose a new method to correct for these

Microwave Imaging of Three-Dimensional Targets by Means of an Inexact-Newton-Based Inversion Algorithm

Directory of Open Access Journals (Sweden)

Claudio Estatico

2013-01-01

Full Text Available A microwave imaging method previously developed for tomographic inspection of dielectric targets is extended to three-dimensional objects. The approach is based on the full vector equations of the electromagnetic inverse scattering problem. The ill-posedness of the problem is faced by the application of an inexact-Newton method. Preliminary reconstruction results are reported.

In vivo Diagnosis of Basal Cell Carcinoma Subtype by Reflectance Confocal Microscopy

NARCIS (Netherlands)

Peppelman, M.; Wolberink, E.A.W.; Blokx, W.A.M.; Kerkhof, P.C.M. van de; Erp, P.E.J. van; Gerritsen, M.J.P.

2013-01-01

Background: Reflectance confocal microscopy (RCM) is a noninvasive imaging technique. Currently, RCM is mainly used for the diagnosis of melanoma and nonmelanoma skin cancer including basal cell carcinoma (BCC). Until now, it has not been possible to distinguish between subtypes of BCC using RCM.

Three-Dimensional Visualization of Interfacial Phenomena Using Confocal Microscopy

Science.gov (United States)

Shieh, Ian C.

Surfactants play an integral role in numerous functions ranging from stabilizing the emulsion in a favorite salad dressing to organizing the cellular components that make life possible. We are interested in lung surfactant, which is a mixture of lipids and proteins essential for normal respiration because it modulates the surface tension of the air-liquid interface of the thin fluid lining in the lungs. Through this surface tension modulation, lung surfactant ensures effortless lung expansion and prevents lung collapse during exhalation, thereby effecting proper oxygenation of the bloodstream. The function of lung surfactant, as well as numerous interfacial lipid systems, is not solely dictated by the behavior of materials confined to the two-dimensional interface. Rather, the distributions of materials in the liquid subphase also greatly influence the performance of interfacial films of lung surfactant. Therefore, to better understand the behavior of lung surfactant and other interfacial lipid systems, we require a three-dimensional characterization technique. In this dissertation, we have developed a novel confocal microscopy methodology for investigating the interfacial phenomena of surfactants at the air-liquid interface of a Langmuir trough. Confocal microscopy provides the excellent combination of in situ, fast, three-dimensional visualization of multiple components of the lung surfactant system that other characterization techniques lack. We detail the solutions to the numerous challenges encountered when imaging a dynamic air-liquid interface with a high-resolution technique like confocal microscopy. We then use confocal microscopy to elucidate the distinct mechanisms by which a polyelectrolyte (chitosan) and nonadsorbing polymer (polyethylene glycol) restore the function of lung surfactant under inhibitory conditions mimicking the effects of lung trauma. Beyond this physiological model, we also investigate several one- and two-component interfacial films

Efficacy of photodynamic therapy against larvae of Aedes aegypti: confocal microscopy and fluorescence-lifetime imaging

Science.gov (United States)

de Souza, L. M.; Pratavieira, S.; Inada, N. M.; Kurachi, C.; Corbi, J.; Guimarães, F. E. G.; Bagnato, V. S.

2014-03-01

Recently a few demonstration on the use of Photodynamic Reaction as possibility to eliminate larvae that transmit diseases for men has been successfully demonstrated. This promising tool cannot be vastly used due to many problems, including the lake of investigation concerning the mechanisms of larvae killing as well as security concerning the use of photosensitizers in open environment. In this study, we investigate some of the mechanisms in which porphyrin (Photogem) is incorporated on the Aedes aegypti larvae previously to illumination and killing. Larvae at second instar were exposed to the photosensitizer and after 30 minutes imaged by a confocal fluorescence microscope. It was observed the presence of photosensitizer in the gut and at the digestive tract of the larva. Fluorescence-Lifetime Imaging showed greater photosensitizer concentration in the intestinal wall of the samples, which produces a strong decrease of the Photogem fluorescence lifetime. For Photodynamic Therapy exposition to different light doses and concentrations of porphyrin were employed. Three different light sources (LED, Fluorescent lamp, Sun light) also were tested. Sun light and fluorescent lamp shows close to 100% of mortality after 24 hrs. of illumination. These results indicate the potential use of photodynamic effect against the LARVAE of Aedes aegypti.

Combined TRMM Microwave Imager (TMI) and Precipitation Radar (PR) Gridded Orbital Data Set (G2B31) V6

Data.gov (United States)

National Aeronautics and Space Administration — Combined TRMM Microwave Imager (TMI) and Precipitation Radar (PR) gridded orbital rainfall data, is a special product derived from the TRMM standard product (2B-31)...

Confocal microscopy of thick tissue sections: 3D visualizaiton of rat kidney glomeruli

Science.gov (United States)

Confocal laser scanning microscopy (CLSM) as a technique capable of generating serial sections of whole-mount tissue and then reassembling the computer-acquired images as a virtual 3-dimentional structure. In many ways CLSM offers an alternative to traditional sectioning approac...

Confocal Microscopy of thick tissue sections: 3D Visualization of rat kidney glomeruli

Science.gov (United States)

Confocal laser scanning microscopy (CLSM) as a technique capable of generating serial sections of whole-mount tissue and then reassembling the computer-acquired images as a virtual 3-dimentional structure. In many ways CLSM offers an alternative to traditional sectioning approac...

Insight into the Microbial Multicellular Lifestyle via Flow-Cell Technology and Confocal Microscopy

DEFF Research Database (Denmark)

Pamp, Sünje Johanna; Sternberg, Claus; Tolker-Nielsen, Tim

2009-01-01

, industry, and human health. Accordingly a number of biofilm model systems, molecular tools, microscopic techniques, and image analysis programs have been employed for the study of biofilms under controlled and reproducible conditions. Studies using confocal laser scanning microscopy (CLSM) of biofilms...

Re-scan confocal microscopy (RCM) improves the resolution of confocal microscopy and increases the sensitivity

NARCIS (Netherlands)

de Luca, Giulia; Breedijk, Ronald; Hoebe, Ron; Stallinga, Sjoerd; Manders, Erik

2017-01-01

Re-scan confocal microscopy (RCM) is a new super-resolution technique based on a standard confocal microscope extended with a re-scan unit in the detection path that projects the emitted light onto a sensitive camera. In this paper the fundamental properties of RCM, lateral resolution, axial

Re-scan confocal microscopy (RCM) improves the resolution of confocal microscopy and increases the sensitivity

NARCIS (Netherlands)

De Luca, G.; Breedijk, R.; Hoebe, R.; Stallinga, S.; Manders, E.

Re-scan confocal microscopy (RCM) is a new super-resolution technique based on a standard confocal microscope extended with a re-scan unit in the detection path that projects the emitted light onto a sensitive camera. In this paper the fundamental properties of RCM, lateral resolution, axial

Association between dermoscopic and reflectance confocal microscopy features of cutaneous melanoma with BRAF mutational status.

Science.gov (United States)

Bombonato, C; Ribero, S; Pozzobon, F C; Puig-Butille, J A; Badenas, C; Carrera, C; Malvehy, J; Moscarella, E; Lallas, A; Piana, S; Puig, S; Argenziano, G; Longo, C

2017-04-01

Melanomas harbouring common genetic mutations might share certain morphological features detectable with dermoscopy and reflectance confocal microscopy. BRAF mutational status is crucial for the management of metastatic melanoma. To correlate the dermoscopic characteristics of primary cutaneous melanomas with BRAF mutational status. Furthermore, a subset of tumours has also been analysed for the presence of possible confocal features that might be linked with BRAF status. Retrospectively acquired dermoscopic and confocal images of patients with melanoma in tertiary referral academic centres: Skin Cancer Unit in Reggio Emilia and at the Melanoma Unit in Barcelona. Kruskal-Wallis test, logistic regressions, univariate and multivariate analyses have been performed to find dermoscopic and confocal features significantly correlated with BRAF mutational status. Dermoscopically, the presence of irregular peripheral streaks and ulceration were positive predictors of BRAF-mutated melanomas with a statistically significance value, while dotted vessels were more represented in wild-type melanomas. None of the evaluated reflectance confocal microscopy features were correlated with genetic profiling. Ulceration and irregular peripheral streaks represent dermoscopic feature indicative for BRAF-mutated melanoma, while dotted vessels are suggestive for wild-type melanoma. © 2016 European Academy of Dermatology and Venereology.

Microwave ablation devices for interventional oncology.

Science.gov (United States)

Ward, Robert C; Healey, Terrance T; Dupuy, Damian E

2013-03-01

Microwave ablation is one of the several options in the ablation armamentarium for the treatment of malignancy, offering several potential benefits when compared with other ablation, radiation, surgical and medical treatment modalities. The basic microwave system consists of the generator, power distribution system and antennas. Often under image (computed tomography or ultrasound) guidance, a needle-like antenna is inserted percutaneously into the tumor, where local microwave electromagnetic radiation is emitted from the probe's active tip, producing frictional tissue heating, capable of causing cell death by coagulation necrosis. Half of the microwave ablation systems use a 915 MHz generator and the other half use a 2450 MHz generator. To date, there are no completed clinical trials comparing microwave devices head-to-head. Prospective comparisons of microwave technology with other treatment alternatives, as well as head-to-head comparison with each microwave device, is needed if this promising field will garner more widespread support and use in the oncology community.

Combined TRMM Microwave Imager (TMI) and Precipitation Radar (PR) Gridded Orbital Data Set (G2A12) V6

Data.gov (United States)

National Aeronautics and Space Administration — The TRMM Microwave Imager (TMI) Gridded Orbital rainfall data, a special product derived from the TRMM standard product, TMI rain profile (2A-12), and mapped to a...

Intraoperative confocal microscopy in the visualization of 5-aminolevulinic acid fluorescence in low-grade gliomas.

Science.gov (United States)

Sanai, Nader; Snyder, Laura A; Honea, Norissa J; Coons, Stephen W; Eschbacher, Jennifer M; Smith, Kris A; Spetzler, Robert F

2011-10-01

Greater extent of resection (EOR) for patients with low-grade glioma (LGG) corresponds with improved clinical outcome, yet remains a central challenge to the neurosurgical oncologist. Although 5-aminolevulinic acid (5-ALA)-induced tumor fluorescence is a strategy that can improve EOR in gliomas, only glioblastomas routinely fluoresce following 5-ALA administration. Intraoperative confocal microscopy adapts conventional confocal technology to a handheld probe that provides real-time fluorescent imaging at up to 1000× magnification. The authors report a combined approach in which intraoperative confocal microscopy is used to visualize 5-ALA tumor fluorescence in LGGs during the course of microsurgical resection. Following 5-ALA administration, patients with newly diagnosed LGG underwent microsurgical resection. Intraoperative confocal microscopy was conducted at the following points: 1) initial encounter with the tumor; 2) the midpoint of tumor resection; and 3) the presumed brain-tumor interface. Histopathological analysis of these sites correlated tumor infiltration with intraoperative cellular tumor fluorescence. Ten consecutive patients with WHO Grades I and II gliomas underwent microsurgical resection with 5-ALA and intraoperative confocal microscopy. Macroscopic tumor fluorescence was not evident in any patient. However, in each case, intraoperative confocal microscopy identified tumor fluorescence at a cellular level, a finding that corresponded to tumor infiltration on matched histological analyses. Intraoperative confocal microscopy can visualize cellular 5-ALA-induced tumor fluorescence within LGGs and at the brain-tumor interface. To assess the clinical value of 5-ALA for high-grade gliomas in conjunction with neuronavigation, and for LGGs in combination with intraoperative confocal microscopy and neuronavigation, a Phase IIIa randomized placebo-controlled trial (BALANCE) is underway at the authors' institution.

Wideband Radio Frequency Interference Detection for Microwave Radiometer Subsystem

Data.gov (United States)

National Aeronautics and Space Administration — Anthropogenic Radio-Frequency Interference (RFI) is threatening the quality and utility of multi-frequency passive microwave radiometry. The GPM Microwave Imager...

The microwave effects on the properties of alumina at high frequencies of microwave sintering

International Nuclear Information System (INIS)

Sudiana, I. Nyoman; Ngkoimani, La Ode; Usman, Ida; Mitsudo, Seitaro; Sako, Katsuhide; Inagaki, Shunsuke; Aripin, H.

2016-01-01

Microwave sintering of materials has attracted much research interest because of its significant advantages (e.g. reduced sintering temperatures and soaking times) over the conventional heating. Most researchers compared processes that occurred during the microwave and conventional heating at the same temperature and time. The enhancements found in the former method are indicated as a 'non-thermal effect' which is usually used for explaining the phenomena in microwave processing. Numerous recent studies have been focused on the effect to elucidate the microwave interaction mechanism with materials. Moreover, recent progress on microwave sources such as gyrotrons has opened the possibility for processing materials by using a higher microwave frequency. Therefore, the technology is expected to exhibit a stronger non-thermal effect. This paper presents results from a series of experiments to study the non-thermal effect on microwave sintered alumina. Sintering by using a wide rage of microwave frequencies up to 300 GHz as well as a conventional furnace was carried out. The linear shrinkages of samples for each sintering method were measured. Pores and grains taken from scanning electron microstructure (SEM) images of cut surfaces were also examined. The results of a comparative study of the shrinkages and microstructure evolutions of the sintered samples under annealing in microwave heating systems and in an electric furnace were analyzed. A notably different behavior of the shrinkages and microstructures of alumina after being annealed was found. The results suggested that microwave radiations provided an additional force for mass transports. The results also indicated that the sintering process depended on microwave frequencies.

The microwave effects on the properties of alumina at high frequencies of microwave sintering

Energy Technology Data Exchange (ETDEWEB)

Sudiana, I. Nyoman, E-mail: sudiana75@yahoo.com; Ngkoimani, La Ode; Usman, Ida [Department of Physics, Faculty of Mathematic and Natural Science, Halu Oleo University, Kampus Bumi Tridharma Anduonohu, Kendari 93232 (Indonesia); Mitsudo, Seitaro; Sako, Katsuhide; Inagaki, Shunsuke [Research Center for Development of Far-Infrared Region, University of Fukui, 3-9-1 Bunkyo, Fukui-shi 910-8507 (Japan); Aripin, H. [Center for Material Processing and Renewable Energy, Faculty of Learning Teacher and Education Science, Siliwangi University, Jl. Siliwangi 24 Tasikmalaya 46115, West Java (Indonesia)

2016-03-11

Microwave sintering of materials has attracted much research interest because of its significant advantages (e.g. reduced sintering temperatures and soaking times) over the conventional heating. Most researchers compared processes that occurred during the microwave and conventional heating at the same temperature and time. The enhancements found in the former method are indicated as a 'non-thermal effect' which is usually used for explaining the phenomena in microwave processing. Numerous recent studies have been focused on the effect to elucidate the microwave interaction mechanism with materials. Moreover, recent progress on microwave sources such as gyrotrons has opened the possibility for processing materials by using a higher microwave frequency. Therefore, the technology is expected to exhibit a stronger non-thermal effect. This paper presents results from a series of experiments to study the non-thermal effect on microwave sintered alumina. Sintering by using a wide rage of microwave frequencies up to 300 GHz as well as a conventional furnace was carried out. The linear shrinkages of samples for each sintering method were measured. Pores and grains taken from scanning electron microstructure (SEM) images of cut surfaces were also examined. The results of a comparative study of the shrinkages and microstructure evolutions of the sintered samples under annealing in microwave heating systems and in an electric furnace were analyzed. A notably different behavior of the shrinkages and microstructures of alumina after being annealed was found. The results suggested that microwave radiations provided an additional force for mass transports. The results also indicated that the sintering process depended on microwave frequencies.

Adaptive Microwave Staring Correlated Imaging for Targets Appearing in Discrete Clusters.

Science.gov (United States)

Tian, Chao; Jiang, Zheng; Chen, Weidong; Wang, Dongjin

2017-10-21

Microwave staring correlated imaging (MSCI) can achieve ultra-high resolution in real aperture staring radar imaging using the correlated imaging process (CIP) under all-weather and all-day circumstances. The CIP must combine the received echo signal with the temporal-spatial stochastic radiation field. However, a precondition of the CIP is that the continuous imaging region must be discretized to a fine grid, and the measurement matrix should be accurately computed, which makes the imaging process highly complex when the MSCI system observes a wide area. This paper proposes an adaptive imaging approach for the targets in discrete clusters to reduce the complexity of the CIP. The approach is divided into two main stages. First, as discrete clustered targets are distributed in different range strips in the imaging region, the transmitters of the MSCI emit narrow-pulse waveforms to separate the echoes of the targets in different strips in the time domain; using spectral entropy, a modified method robust against noise is put forward to detect the echoes of the discrete clustered targets, based on which the strips with targets can be adaptively located. Second, in a strip with targets, the matched filter reconstruction algorithm is used to locate the regions with targets, and only the regions of interest are discretized to a fine grid; sparse recovery is used, and the band exclusion is used to maintain the non-correlation of the dictionary. Simulation results are presented to demonstrate that the proposed approach can accurately and adaptively locate the regions with targets and obtain high-quality reconstructed images.

A multi-axis confocal rheoscope for studying shear flow of structured fluids

KAUST Repository

Lin, Neil Y. C.

2014-03-01

We present a new design for a confocal rheoscope that enables uniform uniaxial or biaxial shear. The design consists of two precisely positioned parallel plates with a gap that can be adjusted down to 2 ±0.1 μm, allowing for the exploration of confinement effects. By using our shear cell in conjunction with a biaxial force measurement device and a high-speed confocal microscope, we are able to measure the real-time biaxial stress while simultaneously imaging the material three-dimensional structure. We illustrate the importance of the instrument capabilities by discussing the applications of this instrument in current and future research topics in colloidal suspensions. © 2014 AIP Publishing LLC.

Mapping microscopic order in plant and mammalian cells and tissues: novel differential polarization attachment for new generation confocal microscopes (DP-LSM)

Science.gov (United States)

Steinbach, G.; Pawlak, K.; Pomozi, I.; Tóth, E. A.; Molnár, A.; Matkó, J.; Garab, G.

2014-03-01

Elucidation of the molecular architecture of complex, highly organized molecular macro-assemblies is an important, basic task for biology. Differential polarization (DP) measurements, such as linear (LD) and circular dichroism (CD) or the anisotropy of the fluorescence emission (r), which can be carried out in a dichrograph or spectrofluorimeter, respectively, carry unique, spatially averaged information about the molecular organization of the sample. For inhomogeneous samples—e.g. cells and tissues—measurements on macroscopic scale are not satisfactory, and in some cases not feasible, thus microscopic techniques must be applied. The microscopic DP-imaging technique, when based on confocal laser scanning microscope (LSM), allows the pixel by pixel mapping of anisotropy of a sample in 2D and 3D. The first DP-LSM configuration, which, in fluorescence mode, allowed confocal imaging of different DP quantities in real-time, without interfering with the ‘conventional’ imaging, was built on a Zeiss LSM410. It was demonstrated to be capable of determining non-confocally the linear birefringence (LB) or LD of a sample and, confocally, its FDLD (fluorescence detected LD), the degree of polarization (P) and the anisotropy of the fluorescence emission (r), following polarized and non-polarized excitation, respectively (Steinbach et al 2009 Acta Histochem.111 316-25). This DP-LSM configuration, however, cannot simply be adopted to new generation microscopes with considerably more compact structures. As shown here, for an Olympus FV500, we designed an easy-to-install DP attachment to determine LB, LD, FDLD and r, in new-generation confocal microscopes, which, in principle, can be complemented with a P-imaging unit, but specifically to the brand and type of LSM.

Mapping microscopic order in plant and mammalian cells and tissues: novel differential polarization attachment for new generation confocal microscopes (DP-LSM)

International Nuclear Information System (INIS)

Steinbach, G; Pawlak, K; Garab, G; Pomozi, I; Tóth, E A; Molnár, A; Matkó, J

2014-01-01

Elucidation of the molecular architecture of complex, highly organized molecular macro-assemblies is an important, basic task for biology. Differential polarization (DP) measurements, such as linear (LD) and circular dichroism (CD) or the anisotropy of the fluorescence emission (r), which can be carried out in a dichrograph or spectrofluorimeter, respectively, carry unique, spatially averaged information about the molecular organization of the sample. For inhomogeneous samples—e.g. cells and tissues—measurements on macroscopic scale are not satisfactory, and in some cases not feasible, thus microscopic techniques must be applied. The microscopic DP-imaging technique, when based on confocal laser scanning microscope (LSM), allows the pixel by pixel mapping of anisotropy of a sample in 2D and 3D. The first DP-LSM configuration, which, in fluorescence mode, allowed confocal imaging of different DP quantities in real-time, without interfering with the ‘conventional’ imaging, was built on a Zeiss LSM410. It was demonstrated to be capable of determining non-confocally the linear birefringence (LB) or LD of a sample and, confocally, its FDLD (fluorescence detected LD), the degree of polarization (P) and the anisotropy of the fluorescence emission (r), following polarized and non-polarized excitation, respectively (Steinbach et al 2009 Acta Histochem.111 316–25). This DP-LSM configuration, however, cannot simply be adopted to new generation microscopes with considerably more compact structures. As shown here, for an Olympus FV500, we designed an easy-to-install DP attachment to determine LB, LD, FDLD and r, in new-generation confocal microscopes, which, in principle, can be complemented with a P-imaging unit, but specifically to the brand and type of LSM. (paper)

Confocal scanning microscope for nuclear photoemulsion

International Nuclear Information System (INIS)

Batusov, Yu.A.; Kovalev, Yu.S.; Soroko, L.M.

2005-01-01

The application of the confocal scanning microscope to the objects in the nuclear photoemulsion is described. An array of 27 microtomograms of single silver grain is shown. The cross sections of the same particle track of diameter 1 μm, detected by means of the confocal scanning microscope with open and annular apertures, are presented. It was shown that the confocal scanning microscope opens indeed new opportunities for the nuclear photoemulsion technique to get previously inaccessible information for physics of the short-living particles

Fluorescence lifetime measurement with confocal endomicroscopy for direct analysis of tissue biochemistry in vivo

Directory of Open Access Journals (Sweden)

Youngjae Won

2016-08-01

Full Text Available Confocal endomicroscopy is a powerful tool for in vivo real-time imaging at cellular resolution inside a living body without tissue resection. Microscopic fluorescence lifetime measurement can provide information about localized biochemical conditions such as pH and the concentrations of oxygen and calcium. We hypothesized that combining these techniques could assist accurate cancer discrimination by providing both biochemical and morphological information. We designed a dual-mode experimental setup for confocal endomicroscopic imaging and fluorescence lifetime measurement and applied it to a mouse xenograft model of activated human pancreatic cancer generated by subcutaneous injection of AsPC-1 tumor cells. Using this method with pH-sensitive sodium fluorescein injection, we demonstrated discrimination between normal and cancerous tissues in a living mouse. With further development, this method may be useful for clinical cancer detection.

Confocal laser microscopic imaging of conspicuous facial pores in vivo: relation between the appearance and the internal structure of skin.

Science.gov (United States)

Sugata, Keiichi; Nishijima, Takafumi; Kitahara, Takashi; Takema, Yoshinori

2008-05-01

Conspicuous facial pores are one of the more serious esthetic defects of most concern to women. Previous microscopic observations of the skin surface around conspicuous pores have discovered large hollows and uneven skin tone. In this study, the observation area was extended from the skin surface to deeper skin to find the characteristic features of conspicuous pores in a wider spectrum. First, a magnified surface image of the cheek skin was obtained using a video microscope. Second, replicas were collected from the same area. Third, the horizontal cross-sectioned images of the epidermis and papillary dermis in different depths were non-invasively obtained using in vivo confocal laser scanning microscopy. These images were compared with each other to find a correlation between features of the skin surface and those of deeper layers. In cross-sectioned images of conspicuous pores, a strongly undulated epidermal-dermal junction was commonly observed around a pore's opening. Areas with this feature correlated well to the areas with larger hollows and an uneven skin tone. Our results indicate that there is a positive correlation between the incidence of the characteristic feature at the epidermal-dermal junction and the visual appearance of a pore.

Reflectance confocal microscopy: non-invasive distinction between actinic keratosis and squamous cell carcinoma

NARCIS (Netherlands)

Peppelman, M.; Nguyen, K.P.; Hoogedoorn, L.; Erp, P.E.J. van; Gerritsen, M.J.P.

2015-01-01

BACKGROUND: Early recognition of squamous cell carcinoma (SCC) is difficult. Non-invasive reflectance confocal microscopic (RCM) imaging of the skin is a promising diagnostic technique. Although several RCM features for SCC and AK have been described, it is not determined whether RCM has the ability

Semi-automated scoring of triple-probe FISH in human sperm using confocal microscopy.

Science.gov (United States)

Branch, Francesca; Nguyen, GiaLinh; Porter, Nicholas; Young, Heather A; Martenies, Sheena E; McCray, Nathan; Deloid, Glen; Popratiloff, Anastas; Perry, Melissa J

2017-09-01

Structural and numerical sperm chromosomal aberrations result from abnormal meiosis and are directly linked to infertility. Any live births that arise from aneuploid conceptuses can result in syndromes such as Kleinfelter, Turners, XYY and Edwards. Multi-probe fluorescence in situ hybridization (FISH) is commonly used to study sperm aneuploidy, however manual FISH scoring in sperm samples is labor-intensive and introduces errors. Automated scoring methods are continuously evolving. One challenging aspect for optimizing automated sperm FISH scoring has been the overlap in excitation and emission of the fluorescent probes used to enumerate the chromosomes of interest. Our objective was to demonstrate the feasibility of combining confocal microscopy and spectral imaging with high-throughput methods for accurately measuring sperm aneuploidy. Our approach used confocal microscopy to analyze numerical chromosomal abnormalities in human sperm using enhanced slide preparation and rigorous semi-automated scoring methods. FISH for chromosomes X, Y, and 18 was conducted to determine sex chromosome disomy in sperm nuclei. Application of online spectral linear unmixing was used for effective separation of four fluorochromes while decreasing data acquisition time. Semi-automated image processing, segmentation, classification, and scoring were performed on 10 slides using custom image processing and analysis software and results were compared with manual methods. No significant differences in disomy frequencies were seen between the semi automated and manual methods. Samples treated with pepsin were observed to have reduced background autofluorescence and more uniform distribution of cells. These results demonstrate that semi-automated methods using spectral imaging on a confocal platform are a feasible approach for analyzing numerical chromosomal aberrations in sperm, and are comparable to manual methods. © 2017 International Society for Advancement of Cytometry. © 2017

Microwave photonics shines

Science.gov (United States)

Won, Rachel

2011-12-01

The combination of microwave photonics and optics has advanced many applications in defence, wireless communications, imaging and network infrastructure. Rachel Won talks to Jianping Yao from the University of Ottawa in Canada about the importance of this growing field.

Lateral Brightness Correction in Confocal Microscopy Images Using Mathematical Morphology Filters

Czech Academy of Sciences Publication Activity Database

Michálek, Jan; Čapek, M.; Mao, X. W.; Kubínová, Lucie

2010-01-01

Roč. 16, Suppl.2 (2010), s. 758-759 ISSN 1431-9276. [Microscopy and Microanalysis 2010. Portland, 01.08.2010-05.08.2010] R&D Projects: GA MŠk(CZ) LC06063; GA MŠk(CZ) ME09010; GA ČR(CZ) GA102/08/0691; GA ČR(CZ) GA304/09/0733 Institutional research plan: CEZ:AV0Z50110509 Keywords : Lipschitz cover * lateral intensity correction * confocal microscopy Subject RIV: JD - Computer Applications, Robotics Impact factor: 2.179, year: 2010

How the confocal laser scanning microscope entered biological research.

Science.gov (United States)

Amos, W B; White, J G

2003-09-01

A history of the early development of the confocal laser scanning microscope in the MRC Laboratory of Molecular Biology in Cambridge is presented. The rapid uptake of this technology is explained by the wide use of fluorescence in the 80s. The key innovations were the scanning of the light beam over the specimen rather than vice-versa and a high magnification at the level of the detector, allowing the use of a macroscopic iris. These were followed by an achromatic all-reflective relay system, a non-confocal transmission detector and novel software for control and basic image processing. This design was commercialized successfully and has been produced and developed over 17 years, surviving challenges from alternative technologies, including solid-state scanning systems. Lessons are pointed out from the unusual nature of the original funding and research environment. Attention is drawn to the slow adoption of the instrument in diagnostic medicine, despite promising applications.

Noncontact ballistic motion measurement using a fiber-optic confocal sensor

International Nuclear Information System (INIS)

Shafir, E.; Berkovic, G.; Horovitz, Y.; Appelbaum, G.; Moshe, E.; Horovitz, E.; Skutelski, A.; Werdiger, M.; Perelmutter, L.; Sudai, M.

2007-01-01

A fiber-optic confocal sensor for noncontact ballistic measurements is described. Determination of motion at velocities of 1.7 km/s with an uncertainty as small as ±0.3% is demonstrated for both a projectile and a free-surface target. The fibers detect the passage of the object at their conjugate image points created by low F/ optics. This results in an output signal comprising a train of sharp pulses each precisely identifying when the ballistic object traverses an image point. Since the ballistic object does not contact the sensor at the time of imaging, the measurements do not perturb the motion, enabling multi-fragment measurement, as well as repetitive measurements of the same object point

Confocal arthroscopy-based patient-specific constitutive models of cartilaginous tissues - II: prediction of reaction force history of meniscal cartilage specimens.

Science.gov (United States)

Taylor, Zeike A; Kirk, Thomas B; Miller, Karol

2007-10-01

The theoretical framework developed in a companion paper (Part I) is used to derive estimates of mechanical response of two meniscal cartilage specimens. The previously developed framework consisted of a constitutive model capable of incorporating confocal image-derived tissue microstructural data. In the present paper (Part II) fibre and matrix constitutive parameters are first estimated from mechanical testing of a batch of specimens similar to, but independent from those under consideration. Image analysis techniques which allow estimation of tissue microstructural parameters form confocal images are presented. The constitutive model and image-derived structural parameters are then used to predict the reaction force history of the two meniscal specimens subjected to partially confined compression. The predictions are made on the basis of the specimens' individual structural condition as assessed by confocal microscopy and involve no tuning of material parameters. Although the model does not reproduce all features of the experimental curves, as an unfitted estimate of mechanical response the prediction is quite accurate. In light of the obtained results it is judged that more general non-invasive estimation of tissue mechanical properties is possible using the developed framework.

A Miniaturized Antenna with Negative Index Metamaterial Based on Modified SRR and CLS Unit Cell for UWB Microwave Imaging Applications

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Md. Moinul Islam

2015-01-01

Full Text Available A miniaturized antenna employing a negative index metamaterial with modified split-ring resonator (SRR and capacitance-loaded strip (CLS unit cells is presented for Ultra wideband (UWB microwave imaging applications. Four left-handed (LH metamaterial (MTM unit cells are located along one axis of the antenna as the radiating element. Each left-handed metamaterial unit cell combines a modified split-ring resonator (SRR with a capacitance-loaded strip (CLS to obtain a design architecture that simultaneously exhibits both negative permittivity and negative permeability, which ensures a stable negative refractive index to improve the antenna performance for microwave imaging. The antenna structure, with dimension of 16 × 21 × 1.6 mm3, is printed on a low dielectric FR4 material with a slotted ground plane and a microstrip feed. The measured reflection coefficient demonstrates that this antenna attains 114.5% bandwidth covering the frequency band of 3.4–12.5 GHz for a voltage standing wave ratio of less than 2 with a maximum gain of 5.16 dBi at 10.15 GHz. There is a stable harmony between the simulated and measured results that indicate improved nearly omni-directional radiation characteristics within the operational frequency band. The stable surface current distribution, negative refractive index characteristic, considerable gain and radiation properties make this proposed negative index metamaterial antenna optimal for UWB microwave imaging applications.

Cement paste surface roughness analysis using coherence scanning interferometry and confocal microscopy

Energy Technology Data Exchange (ETDEWEB)

Apedo, K.L., E-mail: apedo@unistra.fr [ICube, Université de Strasbourg, CNRS, 2 rue Boussingault, 67000 Strasbourg (France); Munzer, C.; He, H. [ICube, INSA de Strasbourg, CNRS, 24 Bld de la Victoire, 67084 Strasbourg (France); Montgomery, P. [ICube, Université de Strasbourg, CNRS, 23 rue du Loess, 67037 Strasbourg (France); Serres, N. [ICube, INSA de Strasbourg, CNRS, 24 Bld de la Victoire, 67084 Strasbourg (France); Fond, C. [ICube, Université de Strasbourg, CNRS, 2 rue Boussingault, 67000 Strasbourg (France); Feugeas, F. [ICube, INSA de Strasbourg, CNRS, 24 Bld de la Victoire, 67084 Strasbourg (France)

2015-02-15

Scanning electron microscopy and scanning probe microscopy have been used for several decades to better understand the microstructure of cementitious materials. Very limited work has been performed to date to study the roughness of cementitious materials by optical microscopy such as coherence scanning interferometry (CSI) and chromatic confocal sensing (CCS). The objective of this paper is to better understand how CSI can be used as a tool to analyze surface roughness and topography of cement pastes. Observations from a series of images acquired using this technique on both polished and unpolished samples are described. The results from CSI are compared with those from a STIL confocal microscopy technique (SCM). Comparison between both optical techniques demonstrates the ability of CSI to measure both polished and unpolished cement pastes. - Highlights: • Coherence scanning interferometry (CSI) was used to analyze cement paste surfaces. • The results from the CSI were compared with those from a confocal microscopy. • 3D roughness parameters were obtained using the window resizing method. • Polished and unpolished cement pastes were studied.

Cement paste surface roughness analysis using coherence scanning interferometry and confocal microscopy

International Nuclear Information System (INIS)

Apedo, K.L.; Munzer, C.; He, H.; Montgomery, P.; Serres, N.; Fond, C.; Feugeas, F.

2015-01-01

Scanning electron microscopy and scanning probe microscopy have been used for several decades to better understand the microstructure of cementitious materials. Very limited work has been performed to date to study the roughness of cementitious materials by optical microscopy such as coherence scanning interferometry (CSI) and chromatic confocal sensing (CCS). The objective of this paper is to better understand how CSI can be used as a tool to analyze surface roughness and topography of cement pastes. Observations from a series of images acquired using this technique on both polished and unpolished samples are described. The results from CSI are compared with those from a STIL confocal microscopy technique (SCM). Comparison between both optical techniques demonstrates the ability of CSI to measure both polished and unpolished cement pastes. - Highlights: • Coherence scanning interferometry (CSI) was used to analyze cement paste surfaces. • The results from the CSI were compared with those from a confocal microscopy. • 3D roughness parameters were obtained using the window resizing method. • Polished and unpolished cement pastes were studied

Microwave Inspection Nondestructive Imaging Array, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — To address the NASA need for advanced NDE sensor technologies for structural materials, Physical Optics Corporation (POC) proposes to develop a new Microwave...

Comparing phototoxicity during the development of a zebrafish craniofacial bone using confocal and light sheet fluorescence microscopy techniques.

Science.gov (United States)

Jemielita, Matthew; Taormina, Michael J; Delaurier, April; Kimmel, Charles B; Parthasarathy, Raghuveer

2013-12-01

The combination of genetically encoded fluorescent proteins and three-dimensional imaging enables cell-type-specific studies of embryogenesis. Light sheet microscopy, in which fluorescence excitation is provided by a plane of laser light, is an appealing approach to live imaging due to its high speed and efficient use of photons. While the advantages of rapid imaging are apparent from recent work, the importance of low light levels to studies of development is not well established. We examine the zebrafish opercle, a craniofacial bone that exhibits pronounced shape changes at early developmental stages, using both spinning disk confocal and light sheet microscopies of fluorescent osteoblast cells. We find normal and aberrant opercle morphologies for specimens imaged with short time intervals using light sheet and spinning disk confocal microscopies, respectively, under equivalent exposure conditions over developmentally-relevant time scales. Quantification of shapes reveals that the differently imaged specimens travel along distinct trajectories in morphological space. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Three-Dimensional Microwave Imaging for Concealed Weapon Detection Using Range Stacking Technique

Directory of Open Access Journals (Sweden)

Weixian Tan

2017-01-01

Full Text Available Three-dimensional (3D microwave imaging has been proven to be well suited for concealed weapon detection application. For the 3D image reconstruction under two-dimensional (2D planar aperture condition, most of current imaging algorithms focus on decomposing the 3D free space Green function by exploiting the stationary phase and, consequently, the accuracy of the final imagery is obtained at a sacrifice of computational complexity due to the need of interpolation. In this paper, from an alternative viewpoint, we propose a novel interpolation-free imaging algorithm based on wavefront reconstruction theory. The algorithm is an extension of the 2D range stacking algorithm (RSA with the advantages of low computational cost and high precision. The algorithm uses different reference signal spectrums at different range bins and then forms the target functions at desired range bin by a concise coherent summation. Several practical issues such as the propagation loss compensation, wavefront reconstruction, and aliasing mitigating are also considered. The sampling criterion and the achievable resolutions for the proposed algorithm are also derived. Finally, the proposed method is validated through extensive computer simulations and real-field experiments. The results show that accurate 3D image can be generated at a very high speed by utilizing the proposed algorithm.

Microscopia confocal en operados de queratoplastia perforante Confocal microscopy in patients operated from penetrating keratoplasty

Directory of Open Access Journals (Sweden)

Zulema Gómez Castillo

2009-06-01

Full Text Available La microscopia confocal es un examen exploratorio, práctico y poco invasivo que permite conocer las características microscópicas del tejido corneal después del trasplante, por lo que constituye una herramienta muy útil en el manejo de los pacientes operados de queratoplastia. El presente trabajo tiene como finalidad describir las características del tejido corneal en pacientes operados de este tipo de trasplante, mediante la microscopia confocal in vivo. MÉTODOS: Se realizó un estudio descriptivo, de corte transversal, en 40 ojos de 40 pacientes operados de queratoplastia perforante, en el Servicio de Córnea del Instituto Cubano de Oftalmología "Ramón Pando Ferrer", de marzo de 2006 a marzo de 2007. Se confeccionó una historia clínica oftalmológica y se les realizó a todos el examen de microscopia confocal en el injerto corneal con el microscopio confocal CONFOSCAN 4. RESULTADOS: La queratopatía bullosa pseudofáquica fue la afección más frecuente previa a la cirugía y estuvo presente en el 77,5 % de los pacientes. En el 72,5 % de los intervenidos se encontró una disminución del grosor corneal. El epitelio presentó alteraciones en el 62,5 % de los pacientes. Todos presentaron afectación de la forma y el tamaño celular endotelial. En el 82,5 % de los pacientes se observó ausencia de plexos nerviosos. CONCLUSIONES: La microscopia confocal como nueva ciencia en el campo de la oftalmología, favorece el seguimiento evolutivo de las queratoplastias perforantes y con esto no solo a prevenir la aparición de posibles complicaciones, sino además de garantizar el éxito de la cirugía y la función refractiva de la córnea.Confocal microscopy is a practical, exploratory and less invassive examination that allows finding out the microscopic characteristics of the corneal tissue after transplantation, so it is a very useful tool for the management of patients operated from keratoplasty. The present paper was aimed at describing

Femtosecond laser subsurface scleral treatment in cadaver human sclera and evaluation using two-photon and confocal microscopy

Science.gov (United States)

Sun, Hui; Fan, Zhongwei; Yan, Ying; Lian, Fuqiang; Kurtz, Ron; Juhasz, Tibor

2016-03-01

Glaucoma is the second-leading cause of blindness worldwide and is often associated with elevated intraocular pressure (IOP). Partial-thickness drainage channels can be created with femtosecond laser in the translucent sclera for the potential treatment of glaucoma. We demonstrate the creation of partial-thickness subsurface drainage channels with the femtosecond laser in the cadaver human eyeballs and describe the application of two-photon microscopy and confocal microscopy for noninvasive imaging of the femtosecond laser created partial-thickness scleral channels in cadaver human eyes. A femtosecond laser operating at a wavelength of 1700 nm was scanned along a rectangular raster pattern to create the partial thickness subsurface drainage channels in the sclera of cadaver human eyes. Analysis of the dimensions and location of these channels is important in understanding their effects. We describe the application of two-photon microscopy and confocal microscopy for noninvasive imaging of the femtosecond laser created partial-thickness scleral channels in cadaver human eyes. High-resolution images, hundreds of microns deep in the sclera, were obtained to allow determination of the shape and dimension of such partial thickness subsurface scleral channels. Our studies suggest that the confocal and two-photon microscopy can be used to investigate femtosecond-laser created partial-thickness drainage channels in the sclera of cadaver human eyes.

Design and Experimental Evaluation of a Non-Invasive Microwave Head Imaging System for Intracranial Haemorrhage Detection.

Directory of Open Access Journals (Sweden)

A T Mobashsher

Full Text Available An intracranial haemorrhage is a life threatening medical emergency, yet only a fraction of the patients receive treatment in time, primarily due to the transport delay in accessing diagnostic equipment in hospitals such as Magnetic Resonance Imaging or Computed Tomography. A mono-static microwave head imaging system that can be carried in an ambulance for the detection and localization of intracranial haemorrhage is presented. The system employs a single ultra-wideband antenna as sensing element to transmit signals in low microwave frequencies towards the head and capture backscattered signals. The compact and low-profile antenna provides stable directional radiation patterns over the operating bandwidth in both near and far-fields. Numerical analysis of the head imaging system with a realistic head model in various situations is performed to realize the scattering mechanism of haemorrhage. A modified delay-and-summation back-projection algorithm, which includes effects of surface waves and a distance-dependent effective permittivity model, is proposed for signal and image post-processing. The efficacy of the automated head imaging system is evaluated using a 3D-printed human head phantom with frequency dispersive dielectric properties including emulated haemorrhages with different sizes located at different depths. Scattered signals are acquired with a compact transceiver in a mono-static circular scanning profile. The reconstructed images demonstrate that the system is capable of detecting haemorrhages as small as 1 cm3. While quantitative analyses reveal that the quality of images gradually degrades with the increase of the haemorrhage's depth due to the reduction of signal penetration inside the head; rigorous statistical analysis suggests that substantial improvement in image quality can be obtained by increasing the data samples collected around the head. The proposed head imaging prototype along with the processing algorithm demonstrates

Fluorescence and confocal imaging of mammalian cells using conjugated oligoelectrolytes with phenylenevinylene core

Energy Technology Data Exchange (ETDEWEB)

Milczarek, Justyna; Pawlowska, Roza; Zurawinski, Remigiusz; Lukasik, Beata; Garner, Logan E.; Chworos, Arkadiusz

2017-05-01

Over the last few years, considerable efforts are taken, in order to find a molecular fluorescent probe fulfilling their applicability requirements. Due to a good optical properties and affinity to biological structures conjugated oligoelectrolytes (COEs) can be considered as a promising dyes for application in fluorescence-based bioimaging. In this work, we synthetized COEs with phenylenevinylene core (PV-COEs) and applied as fluorescent membranous-specific probes. Cytotoxicity effects of each COE were probed on cancerous and non-cancerous cell types and little to no toxicity effects were observed at the high range of concentrations. The intensity of cell fluorescence following the COE staining was determined by the photoluminescence analysis and fluorescence activated cell sorting method (FACS). Intercalation of tested COEs into mammalian cell membranes was revealed by fluorescent and confocal microscopy colocalization with commercial dyes specific for cellular structures including mitochondria, Golgi apparatus and endoplasmic reticulum. The phenylenevinylene conjugated oligoelectrolytes have been found to be suitable for fluorescent bioimaging of mammalian cells and membrane-rich organelles. Due to their water solubility coupled with spontaneous intercalation into cells, favorable photophysical features, ease of cell staining, low cytotoxicity and selectivity for membranous structures, PV-COEs can be applied as markers for fluorescence imaging of a variety of cell types.

Selective Bioparticle Retention and Characterization in a Chip-Integrated Confocal Ultrasonic Cavity

DEFF Research Database (Denmark)

Svennebring, J.; Manneberg, O.; Skafte-Pedersen, Peder

2009-01-01

We demonstrate selective retention and positioning of cells or other bioparticles by ultrasonic manipulation in a microfluidic expansion chamber during microfluidic perfusion. The chamber is designed as a confocal ultrasonic resonator for maximum confinement of the ultrasonic force field at the c......We demonstrate selective retention and positioning of cells or other bioparticles by ultrasonic manipulation in a microfluidic expansion chamber during microfluidic perfusion. The chamber is designed as a confocal ultrasonic resonator for maximum confinement of the ultrasonic force field...... sample feeding, a set of several manipulation functions performed in series is demonstrated: sample bypass-injection-aggregation and retention-positioning. Finally, we demonstrate transillumination microscopy imaging Of Ultrasonically trapped COS-7 cell aggregates. Biotechnol. Bioeng. 2009;103: 323-328....

Live Cell Imaging and 3D Analysis of Angiotensin Receptor Type 1a Trafficking in Transfected Human Embryonic Kidney Cells Using Confocal Microscopy.

Science.gov (United States)

Kadam, Parnika; McAllister, Ryan; Urbach, Jeffrey S; Sandberg, Kathryn; Mueller, Susette C

2017-03-27

Live-cell imaging is used to simultaneously capture time-lapse images of angiotensin type 1a receptors (AT1aR) and intracellular compartments in transfected human embryonic kidney-293 (HEK) cells following stimulation with angiotensin II (Ang II). HEK cells are transiently transfected with plasmid DNA containing AT1aR tagged with enhanced green fluorescent protein (EGFP). Lysosomes are identified with a red fluorescent dye. Live-cell images are captured on a laser scanning confocal microscope after Ang II stimulation and analyzed by software in three dimensions (3D, voxels) over time. Live-cell imaging enables investigations into receptor trafficking and avoids confounds associated with fixation, and in particular, the loss or artefactual displacement of EGFP-tagged membrane receptors. Thus, as individual cells are tracked through time, the subcellular localization of receptors can be imaged and measured. Images must be acquired sufficiently rapidly to capture rapid vesicle movement. Yet, at faster imaging speeds, the number of photons collected is reduced. Compromises must also be made in the selection of imaging parameters like voxel size in order to gain imaging speed. Significant applications of live-cell imaging are to study protein trafficking, migration, proliferation, cell cycle, apoptosis, autophagy and protein-protein interaction and dynamics, to name but a few.

Confocal Laser Endomicroscopy in the Study of Colonic Mucosa in IBD Patients: A Review

Directory of Open Access Journals (Sweden)

Francesca Salvatori

2012-01-01

Full Text Available Confocal laser endomicroscopy (CLE is one of several novel methods that provide real-time, high-resolution imaging at a micronscale via endoscopes. CLE and related technologies are often termed “virtual biopsy” as they simulate the images seen in traditional histology. Recently, the use of CLE was reported in the study of colonic mucosa in patients with inflammatory bowel diseases and in particular in patients affected by ulcerative colitis. CLE has the potential to have an important role in management of IBD patients as it can be used to assess the grading of colitis and in detection of microscopic colitis in endoscopically silent segments. Moreover, CLE can be used in surveillance programs especially in high-risk patients. This report aims to evaluate the current data on the application of confocal endomicroscopy in clinical gastroenterology and particularly in the study of colonic mucosa in UC patients.

Microwave imaging of dielectric cylinder using level set method and conjugate gradient algorithm

International Nuclear Information System (INIS)

Grayaa, K.; Bouzidi, A.; Aguili, T.

2011-01-01

In this paper, we propose a computational method for microwave imaging cylinder and dielectric object, based on combining level set technique and the conjugate gradient algorithm. By measuring the scattered field, we tried to retrieve the shape, localisation and the permittivity of the object. The forward problem is solved by the moment method, while the inverse problem is reformulate in an optimization one and is solved by the proposed scheme. It found that the proposed method is able to give good reconstruction quality in terms of the reconstructed shape and permittivity.

Confocal spectroscopic imaging measurements of depth dependent hydration dynamics in human skin in-vivo

Science.gov (United States)

Behm, P.; Hashemi, M.; Hoppe, S.; Wessel, S.; Hagens, R.; Jaspers, S.; Wenck, H.; Rübhausen, M.

2017-11-01

We present confocal spectroscopic imaging measurements applied to in-vivo studies to determine the depth dependent hydration profiles of human skin. The observed spectroscopic signal covers the spectral range from 810 nm to 2100 nm allowing to probe relevant absorption signals that can be associated with e.g. lipid and water-absorption bands. We employ a spectrally sensitive autofocus mechanism that allows an ultrafast focusing of the measurement spot on the skin and subsequently probes the evolution of the absorption bands as a function of depth. We determine the change of the water concentration in m%. The water concentration follows a sigmoidal behavior with an increase of the water content of about 70% within 5 μm in a depth of about 14 μm. We have applied our technique to study the hydration dynamics of skin before and after treatment with different concentrations of glycerol indicating that an increase of the glycerol concentration leads to an enhanced water concentration in the stratum corneum. Moreover, in contrast to traditional corneometry we have found that the application of Aluminium Chlorohydrate has no impact to the hydration of skin.

Confocal spectroscopic imaging measurements of depth dependent hydration dynamics in human skin in-vivo

Directory of Open Access Journals (Sweden)

P. Behm

2017-11-01

Full Text Available We present confocal spectroscopic imaging measurements applied to in-vivo studies to determine the depth dependent hydration profiles of human skin. The observed spectroscopic signal covers the spectral range from 810 nm to 2100 nm allowing to probe relevant absorption signals that can be associated with e.g. lipid and water-absorption bands. We employ a spectrally sensitive autofocus mechanism that allows an ultrafast focusing of the measurement spot on the skin and subsequently probes the evolution of the absorption bands as a function of depth. We determine the change of the water concentration in m%. The water concentration follows a sigmoidal behavior with an increase of the water content of about 70% within 5 μm in a depth of about 14 μm. We have applied our technique to study the hydration dynamics of skin before and after treatment with different concentrations of glycerol indicating that an increase of the glycerol concentration leads to an enhanced water concentration in the stratum corneum. Moreover, in contrast to traditional corneometry we have found that the application of Aluminium Chlorohydrate has no impact to the hydration of skin.

Indonesia sea surface temperature from TRMM Microwave Imaging (TMI) sensor

Science.gov (United States)

Marini, Y.; Setiawan, K. T.

2018-05-01

We analysis the Tropical Rainfall Measuring Mission's (TRMM) Microwave Imager (TMI) data to monitor the sea surface temperature (SST) of Indonesia waters for a decade of 2005-2014. The TMI SST data shows the seasonal and interannual SST in Indonesian waters. In general, the SST average was highest in March-May period with SST average was 29.4°C, and the lowest was in June – August period with the SST average was 28.5°C. The monthly SST average fluctuation of Indonesian waters for 10 years tends to increase. The lowest SST average of Indonesia occurred in August 2006 with the SST average was 27.6° C, while the maximum occurred in May 2014 with the monthly SST average temperature was 29.9 ° C.

Impact of immersion oils and mounting media on the confocal imaging of dendritic spines.

Science.gov (United States)

Peterson, Brittni M; Mermelstein, Paul G; Meisel, Robert L

2015-03-15

Structural plasticity, such as changes in dendritic spine morphology and density, reflect changes in synaptic connectivity and circuitry. Procedural variables used in different methods for labeling dendritic spines have been quantitatively evaluated for their impact on the ability to resolve individual spines in confocal microscopic analyses. In contrast, there have been discussions, though no quantitative analyses, of the potential effects of choosing specific mounting media and immersion oils on dendritic spine resolution. Here we provide quantitative data measuring the impact of these variables on resolving dendritic spines in 3D confocal analyses. Medium spiny neurons from the rat striatum and nucleus accumbens are used as examples. Both choice of mounting media and immersion oil affected the visualization of dendritic spines, with choosing the appropriate immersion oil as being more imperative. These biologic data are supported by quantitative measures of the 3D diffraction pattern (i.e. point spread function) of a point source of light under the same mounting medium and immersion oil combinations. Although not a new method, this manuscript provides quantitative data demonstrating that different mounting media and immersion oils can impact the ability to resolve dendritic spines. These findings highlight the importance of reporting which mounting medium and immersion oil are used in preparations for confocal analyses, especially when comparing published results from different laboratories. Collectively, these data suggest that choosing the appropriate immersion oil and mounting media is critical for obtaining the best resolution, and consequently more accurate measures of dendritic spine densities. Copyright © 2015 Elsevier B.V. All rights reserved.

High-resolution confocal imaging of wall ingrowth deposition in plant transfer cells: Semi-quantitative analysis of phloem parenchyma transfer cell development in leaf minor veins of Arabidopsis.

Science.gov (United States)

Nguyen, Suong T T; McCurdy, David W

2015-04-23

Transfer cells (TCs) are trans-differentiated versions of existing cell types designed to facilitate enhanced membrane transport of nutrients at symplasmic/apoplasmic interfaces. This transport capacity is conferred by intricate wall ingrowths deposited secondarily on the inner face of the primary cell wall, hence promoting the potential trans-membrane flux of solutes and consequently assigning TCs as having key roles in plant growth and productivity. However, TCs are typically positioned deep within tissues and have been studied mostly by electron microscopy. Recent advances in fluorophore labelling of plant cell walls using a modified pseudo-Schiff-propidium iodide (mPS-PI) staining procedure in combination with high-resolution confocal microscopy have allowed visualization of cellular details of individual tissue layers in whole mounts, hence enabling study of tissue and cellular architecture without the need for tissue sectioning. Here we apply a simplified version of the mPS-PI procedure for confocal imaging of cellulose-enriched wall ingrowths in vascular TCs at the whole tissue level. The simplified mPS-PI staining procedure produced high-resolution three-dimensional images of individual cell types in vascular bundles and, importantly, wall ingrowths in phloem parenchyma (PP) TCs in minor veins of Arabidopsis leaves and companion cell TCs in pea. More efficient staining of tissues was obtained by replacing complex clearing procedures with a simple post-fixation bleaching step. We used this modified procedure to survey the presence of PP TCs in other tissues of Arabidopsis including cotyledons, cauline leaves and sepals. This high-resolution imaging enabled us to classify different stages of wall ingrowth development in Arabidopsis leaves, hence enabling semi-quantitative assessment of the extent of wall ingrowth deposition in PP TCs at the whole leaf level. Finally, we conducted a defoliation experiment as an example of using this approach to statistically

Confocal Laser Endomicroscopy in Inflammatory Bowel Disease

DEFF Research Database (Denmark)

Rasmussen, Ditlev Nytoft; Karstensen, John Gásdal; Riis, Lene Buhl

2015-01-01

included. Next, eligible studies were analysed with respect to several parameters, such as technique and clinical aim and definitions of outcomes. RESULTS: Confocal laser endomicroscopy has been used for a wide range of purposes in inflammatory bowel disease, covering assessment of inflammatory severity...... of confocal laser endomicroscopy for inflammatory bowel disease. METHODS: Available literature was searched systematically for studies applying confocal laser endomicroscopy in Crohn's disease or ulcerative colitis. Relevant literature was reviewed and only studies reporting original clinical data were...... of histological features such as colonic crypts, epithelial gaps and epithelial leakiness to fluorescein. CONCLUSIONS: Confocal laser endomicroscopy remains an experimental but emerging tool for assessment of inflammatory bowel disease. It is the only method that enables in vivo functional assessment...

High harmonic terahertz confocal gyrotron with nonuniform electron beam

Energy Technology Data Exchange (ETDEWEB)

Fu, Wenjie; Guan, Xiaotong; Yan, Yang [THz Research Center, School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China)

2016-01-15

The harmonic confocal gyrotron with nonuniform electron beam is proposed in this paper in order to develop compact and high power terahertz radiation source. A 0.56 THz third harmonic confocal gyrotron with a dual arc section nonuniform electron beam has been designed and investigated. The studies show that confocal cavity has extremely low mode density, and has great advantage to operate at high harmonic. Nonuniform electron beam is an approach to improve output power and interaction efficiency of confocal gyrotron. A dual arc beam magnetron injection gun for designed confocal gyrotron has been developed and presented in this paper.

CloudSat-Based Assessment of GPM Microwave Imager Snowfall Observation Capabilities

Directory of Open Access Journals (Sweden)

Giulia Panegrossi

2017-12-01

Full Text Available The sensitivity of Global Precipitation Measurement (GPM Microwave Imager (GMI high-frequency channels to snowfall at higher latitudes (around 60°N/S is investigated using coincident CloudSat observations. The 166 GHz channel is highlighted throughout the study due to its ice scattering sensitivity and polarization information. The analysis of three case studies evidences the important combined role of total precipitable water (TPW, supercooled cloud water, and background surface composition on the brightness temperature (TB behavior for different snow-producing clouds. A regression tree statistical analysis applied to the entire GMI-CloudSat snowfall dataset indicates which variables influence the 166 GHz polarization difference (166 ∆TB and its relation to snowfall. Critical thresholds of various parameters (sea ice concentration (SIC, TPW, ice water path (IWP are established for optimal snowfall detection capabilities. The 166 ∆TB can identify snowfall events over land and sea when critical thresholds are exceeded (TPW > 3.6 kg·m−2, IWP > 0.24 kg·m−2 over land, and SIC > 57%, TPW > 5.1 kg·m−2 over sea. The complex combined 166 ∆TB-TB relationship at higher latitudes and the impact of supercooled water vertical distribution are also investigated. The findings presented in this study can be exploited to improve passive microwave snowfall detection algorithms.

Effect of transurethral microwave thermotherapy. An evaluation with MR imaging

International Nuclear Information System (INIS)

Nordenstam, G.; Aspelin, P.; Isberg, B.; Svensson, L.; Hallin, A.; Berlin, T.

1996-01-01

Purpose: To detect morphological changes in the prostate, as depicted with MR imaging, in order to clarify the effects of transurethral microwave thermotherapy (TUMT). Material and Methods: Twenty patients with prostatism and a prostatic volume of 30-71 cm 3 underwent MR examination before, the day after, and 6 months after treatment. TUMT was carried out with a Prostatron. A method to detect oedematous changes on heavily T2-weighted MR images was developed and used as an indicator of morphological changes. Results: The study showed some correlation (r=0.59) between the energy given at TUMT and an increased T2 signal. All patients with increased T2 signal except one were found among those who received the highest amount of energy to the prostate. Of 8 patients, 6 showed a symptomatic response to the treatment and 2 did not. There was a weak statistical correlation (r=0.41) between treatment response and increased T2 signal. Conclusion: The study does not support the view that TUMT leads to significant necrosis in the prostate with loss of tissue and retraction. We theorize that the response to TUMT may be caused by a denervation of the prostate. (orig.)

Towards modeling of cardiac micro-structure with catheter-based confocal microscopy: a novel approach for dye delivery and tissue characterization.

Science.gov (United States)

Lasher, Richard A; Hitchcock, Robert W; Sachse, Frank B

2009-08-01

This work presents a methodology for modeling of cardiac tissue micro-structure. The approach is based on catheter-based confocal imaging systems, which are emerging as tools for diagnosis in various clinical disciplines. A limitation of these systems is that a fluorescent marker must be available in sufficient concentration in the imaged region. We introduce a novel method for the local delivery of fluorescent markers to cardiac tissue based on a hydro-gel carrier brought into contact with the tissue surface. The method was tested with living rabbit cardiac tissue and applied to acquire three-dimensional image stacks with a standard inverted confocal microscope and two-dimensional images with a catheter-based confocal microscope. We processed these image stacks to obtain spatial models and quantitative data on tissue microstructure. Volumes of atrial and ventricular myocytes were 4901 +/- 1713 and 10 299 +/-3598 mum (3) (mean+/-sd), respectively. Atrial and ventricular myocyte volume fractions were 72.4 +/-4.7% and 79.7 +/- 2.9% (mean +/-sd), respectively. Atrial and ventricular myocyte density was 165 571 +/- 55 836 and 86 957 +/- 32 280 cells/mm (3) (mean+/-sd), respectively. These statistical data and spatial descriptions of tissue microstructure provide important input for modeling studies of cardiac tissue function. We propose that the described methodology can also be used to characterize diseased tissue and allows for personalized modeling of cardiac tissue.

Multimodality optical coherence tomography and fluorescence confocal scanning laser ophthalmoscopy for image-guided feedback of intraocular injections in mouse models

Science.gov (United States)

Benavides, Oscar R.; Terrones, Benjamin D.; Leeburg, Kelsey C.; Mehanathan, Sankarathi B.; Levine, Edward M.; Tao, Yuankai K.

2018-02-01

Rodent models are robust tools for understanding human retinal disease and function because of their similarities with human physiology and anatomy and availability of genetic mutants. Optical coherence tomography (OCT) has been well-established for ophthalmic imaging in rodents and enables depth-resolved visualization of structures and image-based surrogate biomarkers of disease. Similarly, fluorescence confocal scanning laser ophthalmoscopy (cSLO) has demonstrated utility for imaging endogenous and exogenous fluorescence and scattering contrast in the mouse retina. Complementary volumetric scattering and en face fluorescence contrast from OCT and cSLO, respectively, enables cellular-resolution longitudinal imaging of changes in ophthalmic structure and function. We present a non-contact multimodal OCT+cSLO small animal imaging system with extended working distance to the pupil, which enables imaging during and after intraocular injection. While injections are routinely performed in mice to develop novel models of ophthalmic diseases and screen novel therapeutics, the location and volume delivered is not precisely controlled and difficult to reproduce. Animals were imaged using a custom-built OCT engine and scan-head combined with a modified commercial cSLO scan-head. Post-injection imaging showed structural changes associated with retinal puncture, including the injection track, a retinal elevation, and detachment of the posterior hyaloid. When combined with imagesegmentation, we believe OCT can be used to precisely identify injection locations and quantify injection volumes. Fluorescence cSLO can provide complementary contrast for either fluorescently labeled compounds or transgenic cells for improved specificity. Our non-contact OCT+cSLO system is uniquely-suited for concurrent imaging with intraocular injections, which may be used for real-time image-guided injections.

Application of Confocal Laser Scanning Microscopy in Biology and Medicine

OpenAIRE

I. A. Volkov; N. V. Frigo; L. F. Znamenskaya; O. R. Katunina

2014-01-01

Fluorescence confocal laser scanning microscopy and reflectance confocal laser scanning microscopy are up-to-date highend study methods. Confocal microscopy is used in cell biology and medicine. By using confocal microscopy, it is possible to study bioplasts and localization of protein molecules and other compounds relative to cell or tissue structures, and to monitor dynamic cell processes. Confocal microscopes enable layer-by-layer scanning of test items to create demonstrable 3D models. As...

Development of confocal 3D micro-XRF spectrometer with dual Cr-Mo excitation

International Nuclear Information System (INIS)

Kouichi Tsuji; Kazuhiko Nakano

2007-01-01

A new 3D micro-XRF instrument based on a confocal setup using two independent poly-capillary x-ray lenses and two x-ray sources (Cr and Mo targets) was developed. A full poly-capillary x-ray lens was attached to each x-ray tube. Another half poly-capillary lens was attached to a silicon drift x-ray detector (SDD). The focal spots of the three lenses were adjusted to a common position. The depth resolutions that were evaluated by use of a 10-μm thick Au foil were approximately 90 μm for the x-ray energy of Au Lα. The effects of the dual Cr-Mo x-ray beam excitation were investigated. It was confirmed that the XRF intensity of light elements was increased by applying the Cr-target x-ray tube in a confocal configuration. In the proposed confocal configuration, 3D elemental mapping of the major elements of an amaranth seed was performed nondestructively at ambient air pressure. Each element of the seed showed different mapping images in the different depth layers. (authors)

Development of confocal 3D micro-XRF spectrometer with dual Cr-Mo excitation

Energy Technology Data Exchange (ETDEWEB)

Kouichi Tsuji [Department of Applied Chemistry, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku Osaka 558-8585 (Japan); PRESTO-JST - Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 332-0012 (Japan); Kazuhiko Nakano [Department of Applied Chemistry, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku Osaka 558-8585 (Japan)

2007-05-15

A new 3D micro-XRF instrument based on a confocal setup using two independent poly-capillary x-ray lenses and two x-ray sources (Cr and Mo targets) was developed. A full poly-capillary x-ray lens was attached to each x-ray tube. Another half poly-capillary lens was attached to a silicon drift x-ray detector (SDD). The focal spots of the three lenses were adjusted to a common position. The depth resolutions that were evaluated by use of a 10-{mu}m thick Au foil were approximately 90 {mu}m for the x-ray energy of Au L{alpha}. The effects of the dual Cr-Mo x-ray beam excitation were investigated. It was confirmed that the XRF intensity of light elements was increased by applying the Cr-target x-ray tube in a confocal configuration. In the proposed confocal configuration, 3D elemental mapping of the major elements of an amaranth seed was performed nondestructively at ambient air pressure. Each element of the seed showed different mapping images in the different depth layers. (authors)

Optimising performance of a confocal fluorescence microscope with a differential pinhole

International Nuclear Information System (INIS)

Kakade, Rohan; Walker, John G; Phillips, Andrew J

2016-01-01

The signal-to-noise ratio (SNR)-resolution trade-off is of great importance to bio-imaging applications where the aim is to image the sample using as little light as possible without significantly sacrificing image quality. In this paper the inherent SNR-resolution tradeoff in Confocal Fluorescence Microscopy (CFM) systems is presented by means of an effective tradeoff curve. A CFM system that employs a differential pinhole detection scheme has recently been shown to offer increased resolution, but at the expense of SNR. An optimum profile for the differential pinhole is identified in this paper that offers improved performance over a conventional (circular pinhole) system. The performance enhancement is illustrated through computer simulation. (paper)

Pigmented Nodular Basal Cell Carcinomas in Differential Diagnosis with Nodular Melanomas: Confocal Microscopy as a Reliable Tool for In Vivo Histologic Diagnosis

International Nuclear Information System (INIS)

Casari, A.; Pellacani, G.; Seidenari, S.; Pepe, P.; Longo, C.; Cesinaro, A. M.; Beretti, F.

2011-01-01

Nodular basal cell carcinoma, especially when pigmented, can be in differential diagnosis with nodular melanomas, clinically and dermoscopically. Reflectance confocal microscopy is a relatively new imaging technique that permits to evaluate in vivo skin tumors with a nearly histological resolution. Here, we present four cases of challenging nodular lesions where confocal microscopy was able to clarify the diagnosis.

Analysis of cell-tissue grafts under weightless conditions using confocal fluorescence microscopy

Science.gov (United States)

Volova, L. T.; Milyakova, M. N.; Rossinskaya, V. V.; Boltovskaya, V. V.; Kulagina, L. N.; Kurganskaya, L. V.; Timchenko, P. E.; Timchenko, E. V.; Zherdeva Taskina, Larisa A.

2015-03-01

The research results of monitoring of viable cells in a cellular-tissue graft using confocal laser fluorescence microscopy at 488 nm and 561 nm with the use of fluorophore propidium iodide (propidium iodide, PI Sigma Aldrich USA) are presented. The processing of the received images was carried out using the software ANDOR. It is experimentally shown that the method of confocal fluorescence microscopy is one of the informational methods for detecting cells populated in a 3-D bio-carrier with a resolution of at least 400 nm. Analysis of the received micrographs suggests that the cells that were in a bio-carrier for 30 days in a synchronous ground-based experiment retained their viability compared to a similar space-based experiment in which the cells were hardly detected in a bio-carrier.

Confocal Laser Endomicroscopy in Neurosurgery: A New Technique with Much Potential

Directory of Open Access Journals (Sweden)

David Breuskin

2013-01-01

Full Text Available Technical innovations in brain tumour diagnostic and therapy have led to significant improvements of patient outcome and recurrence free interval. The use of technical devices such as surgical microscopes as well as neuronavigational systems have helped localising tumours as much as fluorescent agents, such as 5-aminolaevulinic acid, have helped visualizing pathologically altered tissue. Nonetheless, intraoperative instantaneous frozen sections and histological diagnosis remain the only method of gaining certainty of the nature of the resected tissue. This technique is time consuming and does not provide close-to-real-time information. In gastroenterology, confocal endoscopy closed the gap between tissue resection and histological examination, providing an almost real-time histological diagnosis. The potential of this technique using a confocal laser endoscope EndoMAG1 by Karl Storz Company was evaluated by our group on pig brains, tumour tissue cell cultures, and fresh human tumour specimen. Here, the authors report for the first time on the results of applying this new technique and provide first confocal endoscopic images of various brain and tumour structures. In all, the technique harbours a very promising potential to provide almost real-time intraoperative diagnosis, but further studies are needed to provide evidence for the technique’s potential.

Design and realisation of a microwave three-dimensional imaging system with application to breast-cancer detection

DEFF Research Database (Denmark)

Zhurbenko, Vitaliy; Rubæk, T.; Krozer, V.

2010-01-01

An active microwave-imaging system for non-invasive detection of breast cancer based on dedicated hardware is described. Thirty-two transceiving channels are used to measure the amplitude and phase of the scattered fields in the three-dimensional (3D) imaging domain using electronic scanning. The 3...... is created within 2 h using the single-frequency reconstruction algorithm. The performance of the system is illustrated by an analysis of the standard deviations in amplitude and phase of a series of measurements as well as by a simple image reconstruction example....... is important for measurement accuracy and reproducibility as well as for patient comfort. The dedicated hardware achieves a receiver noise figure of 2.3 dB at a gain of 97 dB. The operating frequency range is from 0.3 to 3 GHz. The image acquisition time at one frequency is approximately 50 s and an image...

Nondestructive 3D confocal laser imaging with deconvolution of seven whole stardust tracks with complementary XRF and quantitative analysis

International Nuclear Information System (INIS)

Greenberg, M.; Ebel, D.S.

2009-01-01

We present a nondestructive 3D system for analysis of whole Stardust tracks, using a combination of Laser Confocal Scanning Microscopy and synchrotron XRF. 3D deconvolution is used for optical corrections, and results of quantitative analyses of several tracks are presented. The Stardust mission to comet Wild 2 trapped many cometary and ISM particles in aerogel, leaving behind 'tracks' of melted silica aerogel on both sides of the collector. Collected particles and their tracks range in size from submicron to millimeter scale. Interstellar dust collected on the obverse of the aerogel collector is thought to have an average track length of ∼15 (micro)m. It has been our goal to perform a total non-destructive 3D textural and XRF chemical analysis on both types of tracks. To that end, we use a combination of Laser Confocal Scanning Microscopy (LCSM) and X Ray Florescence (XRF) spectrometry. Utilized properly, the combination of 3D optical data and chemical data provides total nondestructive characterization of full tracks, prior to flattening or other destructive analysis methods. Our LCSM techniques allow imaging at 0.075 (micro)m/pixel, without the use of oil-based lenses. A full textural analysis on track No.82 is presented here as well as analysis of 6 additional tracks contained within 3 keystones (No.128, No.129 and No.140). We present a method of removing the axial distortion inherent in LCSM images, by means of a computational 3D Deconvolution algorithm, and present some preliminary experiments with computed point spread functions. The combination of 3D LCSM data and XRF data provides invaluable information, while preserving the integrity of the samples for further analysis. It is imperative that these samples, the first extraterrestrial solids returned since the Apollo era, be fully mapped nondestructively in 3D, to preserve the maximum amount of information prior to other, destructive analysis.

Confocal Raman Microscopy; applications in tissue engineering

NARCIS (Netherlands)

van Apeldoorn, Aart A.

2005-01-01

This dissertation describes the use of confocal Raman microscopy and spectroscopy in the field of tissue engineering. Moreover, it describes the combination of two already existing technologies, namely scanning electron microscopy and confocal Raman spectroscopy in one apparatus for the enhancement

Integrated Confocal and Scanning Probe Microscopy for Biomedical Research

Directory of Open Access Journals (Sweden)

B.J. Haupt

2006-01-01

Full Text Available Atomic force microscopy (AFM continues to be developed, not only in design, but also in application. The new focus of using AFM is changing from pure material to biomedical studies. More frequently, it is being used in combination with other optical imaging methods, such as confocal laser scanning microscopy (CLSM and fluorescent imaging, to provide a more comprehensive understanding of biological systems. To date, AFM has been used increasingly as a precise micromanipulator, probing and altering the mechanobiological characteristics of living cells and tissues, in order to examine specific, receptor-ligand interactions, material properties, and cell behavior. In this review, we discuss the development of this new hybrid AFM, current research, and potential applications in diagnosis and the detection of disease.

Exploring The Limits Of Variational Passive Microwave Retrievals

Science.gov (United States)

Duncan, David Ian

Passive microwave observations from satellite platforms constitute one of the most important data records of the global observing system. Operational since the late 1970s, passive microwave data underpin climate records of precipitation, sea ice extent, water vapor, and more, and contribute significantly to numerical weather prediction via data assimilation. Detailed understanding of the observation errors in these data is key to maximizing their utility for research and operational applications alike. However, the treatment of observation errors in this data record has been lacking and somewhat divergent when considering the retrieval and data assimilation communities. In this study, some limits of passive microwave imager data are considered in light of more holistic treatment of observation errors. A variational retrieval, named the CSU 1DVAR, was developed for microwave imagers and applied to the GMI and AMSR2 sensors for ocean scenes. Via an innovative method to determine forward model error, this retrieval accounts for error covariances across all channels used in the iteration. This improves validation in more complex scenes such as high wind speed and persistently cloudy regimes. In addition, it validates on par with a benchmark dataset without any tuning to in-situ observations. The algorithm yields full posterior error diagnostics and its physical forward model is applicable to other sensors, pending intercalibration. This retrieval is used to explore the viability of retrieving parameters at the limits of the available information content from a typical microwave imager. Retrieval of warm rain, marginal sea ice, and falling snow are explored with the variational retrieval. Warm rain retrieval shows some promise, with greater sensitivity than operational GPM algorithms due to leveraging CloudSat data and accounting for drop size distribution variability. Marginal sea ice is also detected with greater sensitivity than a standard operational retrieval

Depth-variant blind restoration with pupil-phase constraints for 3D confocal microscopy

International Nuclear Information System (INIS)

Hadj, Saima Ben; Blanc-Féraud, Laure; Engler, Gilbert

2013-01-01

Three-dimensional images of confocal laser scanning microscopy suffer from a depth-variant blur, due to refractive index mismatch between the different mediums composing the system as well as the specimen, leading to optical aberrations. Our goal is to develop an image restoration method for 3D confocal microscopy taking into account the blur variation with depth. The difficulty is that optical aberrations depend on the refractive index of the biological specimen. The depth-variant blur function or the Point Spread Function (PSF) is thus different for each observation. A blind or semi-blind restoration method needs to be developed for this system. For that purpose, we use a previously developed algorithm for the joint estimation of the specimen function (original image) and the 3D PSF, the continuously depth-variant PSF is approximated by a convex combination of a set of space-invariant PSFs taken at different depths. We propose to add to that algorithm a pupil-phase constraint for the PSF estimation, given by the the optical instrument geometry. We thus define a blind estimation algorithm by minimizing a regularized criterion in which we integrate the Gerchberg-Saxton algorithm allowing to include these physical constraints. We show the efficiency of this method relying on some numerical tests

Confocal Microscopy and Flow Cytometry System Performance: Assessment of QA Parameters that affect data Quanitification

Science.gov (United States)

Flow and image cytometers can provide useful quantitative fluorescence data. We have devised QA tests to be used on both a flow cytometer and a confocal microscope to assure that the data is accurate, reproducible and precise. Flow Cytometry: We have provided two simple perform...

Spectrally encoded confocal microscopy (SECM) for rapid assessment of breast excision specimens (Conference Presentation)

Science.gov (United States)

Brachtel, Elena F.; Johnson, Nicole B.; Huck, Amelia E.; Rice-Stitt, Travis L.; Vangel, Mark G.; Smith, Barbara L.; Tearney, Guillermo J.; Kang, DongKyun

2016-03-01

Unacceptably large percentage (20-40%) of breast cancer lumpectomy patients are required to undergo multiple surgeries when positive margins are found upon post-operative histologic assessment. If the margin status can be determined during surgery, surgeon can resect additional tissues to achieve tumor-free margin, which will reduce the need for additional surgeries. Spectrally encoded confocal microscopy (SECM) is a high-speed reflectance confocal microscopy technology that has a potential to image the entire surgical margin within a short procedural time. Previously, SECM was shown to rapidly image a large area (10 mm by 10 mm) of human esophageal tissue within a short procedural time (15 seconds). When used in lumpectomy, SECM will be able to image the entire margin surface of ~30 cm2 in around 7.5 minutes. SECM images will then be used to determine margin status intra-operatively. In this paper, we present results from a study of testing accuracy of SECM for diagnosing malignant breast tissues. We have imaged freshly-excised breast specimens (N=46) with SECM. SECM images clearly visualized histomorphologic features associated with normal/benign and malignant breast tissues in a similar manner to histologic images. Diagnostic accuracy was tested by comparing SECM diagnoses made by three junior pathologists with corresponding histologic diagnoses made by a senior pathologist. SECM sensitivity and specificity were high, 0.91 and 0.93, respectively. Intra-observer agreement and inter-observer agreement were also high, 0.87 and 0.84, respectively. Results from this study showed that SECM has a potential to accurately determine margin status during breast cancer lumpectomy.

Localizing Proteins in Fixed Giardia lamblia and Live Cultured Mammalian Cells by Confocal Fluorescence Microscopy.

Science.gov (United States)

Nyindodo-Ogari, Lilian; Schwartzbach, Steven D; Skalli, Omar; Estraño, Carlos E

2016-01-01

Confocal fluorescence microscopy and electron microscopy (EM) are complementary methods for studying the intracellular localization of proteins. Confocal fluorescence microscopy provides a rapid and technically simple method to identify the organelle in which a protein localizes but only EM can identify the suborganellular compartment in which that protein is present. Confocal fluorescence microscopy, however, can provide information not obtainable by EM but required to understand the dynamics and interactions of specific proteins. In addition, confocal fluorescence microscopy of cells transfected with a construct encoding a protein of interest fused to a fluorescent protein tag allows live cell studies of the subcellular localization of that protein and the monitoring in real time of its trafficking. Immunostaining methods for confocal fluorescence microscopy are also faster and less involved than those for EM allowing rapid optimization of the antibody dilution needed and a determination of whether protein antigenicity is maintained under fixation conditions used for EM immunogold labeling. This chapter details a method to determine by confocal fluorescence microscopy the intracellular localization of a protein by transfecting the organism of interest, in this case Giardia lamblia, with the cDNA encoding the protein of interest and then processing these organisms for double label immunofluorescence staining after chemical fixation. Also presented is a method to identify the organelle targeting information in the presequence of a precursor protein, in this case the presequence of the precursor to the Euglena light harvesting chlorophyll a/b binding protein of photosystem II precursor (pLHCPII), using live cell imaging of mammalian COS7 cells transiently transfected with a plasmid encoding a pLHCPII presequence fluorescent protein fusion and stained with organelle-specific fluorescent dyes.

Local Delivery of Fluorescent Dye For Fiber-Optics Confocal Microscopy of the Living Heart

Directory of Open Access Journals (Sweden)

Chao eHuang

2014-09-01

Full Text Available Fiber-optics confocal microscopy (FCM is an emerging imaging technology with various applications in basic research and clinical diagnosis. FCM allows for real-time in situ microscopy of tissue at sub-cellular scale. Recently FCM has been investigated for cardiac imaging, in particular, for discrimination of cardiac tissue during pediatric open-heart surgery. FCM relies on fluorescent dyes. The current clinical approach of dye delivery is based on systemic injection, which is associated with high dye consumption and adverse clinical events. In this study, we investigated approaches for local dye delivery during FCM imaging based on dye carriers attached to the imaging probe. Using three-dimensional confocal microscopy, automated bench tests, and FCM imaging we quantitatively characterized dye release of carriers composed of open-pore foam only and foam loaded with agarose hydrogel. In addition, we compared local dye delivery with a model of systemic dye delivery in the isolated perfused rodent heart. We measured the signal-to-noise ratio of images acquired in various regions of the heart. Our evaluations showed that foam-agarose dye carriers exhibited a prolonged dye release versus foam-only carriers. Foam-agarose dye carriers allowed reliable imaging of 5-9 lines, which is comparable to 4-8 min of continuous dye release. Our study in the living heart revealed that the SNR of FCM images using local and systemic dye delivery is not different. However, we observed differences in the imaged tissue microstructure with the two approaches. Structural features characteristic of microvasculature were solely observed for systemic dye delivery. Our findings suggest that local dye delivery approach for FCM imaging constitutes an important alternative to systemic dye delivery. We suggest that the approach for local dye delivery will facilitate clinical translation of FCM, for instance, for FCM imaging during pediatric heart surgery.

Local delivery of fluorescent dye for fiber-optics confocal microscopy of the living heart.

Science.gov (United States)

Huang, Chao; Kaza, Aditya K; Hitchcock, Robert W; Sachse, Frank B

2014-01-01

Fiber-optics confocal microscopy (FCM) is an emerging imaging technology with various applications in basic research and clinical diagnosis. FCM allows for real-time in situ microscopy of tissue at sub-cellular scale. Recently FCM has been investigated for cardiac imaging, in particular, for discrimination of cardiac tissue during pediatric open-heart surgery. FCM relies on fluorescent dyes. The current clinical approach of dye delivery is based on systemic injection, which is associated with high dye consumption, and adverse clinical events. In this study, we investigated approaches for local dye delivery during FCM imaging based on dye carriers attached to the imaging probe. Using three-dimensional confocal microscopy, automated bench tests, and FCM imaging we quantitatively characterized dye release of carriers composed of open-pore foam only and foam loaded with agarose hydrogel. In addition, we compared local dye delivery with a model of systemic dye delivery in the isolated perfused rodent heart. We measured the signal-to-noise ratio (SNR) of images acquired in various regions of the heart. Our evaluations showed that foam-agarose dye carriers exhibited a prolonged dye release vs. foam-only carriers. Foam-agarose dye carriers allowed reliable imaging of 5-9 lines, which is comparable to 4-8 min of continuous dye release. Our study in the living heart revealed that the SNR of FCM images using local and systemic dye delivery is not different. However, we observed differences in the imaged tissue microstructure with the two approaches. Structural features characteristic of microvasculature were solely observed for systemic dye delivery. Our findings suggest that local dye delivery approach for FCM imaging constitutes an important alternative to systemic dye delivery. We suggest that the approach for local dye delivery will facilitate clinical translation of FCM, for instance, for FCM imaging during pediatric heart surgery.

Study of the collagen structure in the superficial zone and physiological state of articular cartilage using a 3D confocal imaging technique

Directory of Open Access Journals (Sweden)

Zheng Ming H

2008-07-01

the collagen network in the superficial zone during early physiological alteration of articular cartilage. The fibre confocal imaging technology used in this study has allowed developing confocal arthroscopy for in vivo studying the chondrocytes in different depth of articular cartilage. Therefore, the current study has potential to develop an in vivo 3D histology for diagnosis of early osteoarthritis.

Confocal laser endomicroscopy for diagnosis of Barrett´s esophagus

Directory of Open Access Journals (Sweden)

Helmut eNeumann

2012-05-01

Full Text Available Barrett´s esophagus (BE is established as a premalignant condition in the distal esophagus. Current surveillance guidelines recommend random biopsies every 1-2 cm at intervals of 3-5 years. Advanced endoscopic imaging of BE underwent several technical revolutions within the last decade including broad-field (red-flag techniques (e.g. chromoendoscopy and small-field techniques with confocal laser endomicroscopy (CLE at the forefront. In this review we will focus on advanced endoscopic imaging using CLE for the diagnosis and characterization of BE and associated neoplasia. In addition, we will critically discuss the technique of CLE and provide some tricks and hints for the daily routine practice of CLE for diagnosis of BE.

An Attempt of Nondestructive Imaging of Sugar Distribution inside a Fruit Using Microwaves

Science.gov (United States)

Watanabe, Masakazu; Miyakawa, Michio

Chirp Pulse Microwave Computed Tomography (CP-MCT) that was originally developed for noninvasive imaging of a human body was applied to visualize sugar distribution inside a fruit. It can visualize not only permittivity distribution itself of a fruit but also various physical- or chemical-quantities relating to the permittivity value. Almost all fruits are dielectric materials containing much water, sugar, acids and so on. But for water, the principal ingredient of a fruit is sugar. Most of the fruits contain sugar from 8% to 22% by weight at the harvest time. Therefore sugar content distribution should be measured by CP-MCT nondestructively. By using apples and Japanese pears, feasibility of sugar distribution imaging has been evaluated by comparing the gray level of CP-MCT and sugar content of the cross section. The averaged correlation coefficients of the apple and pear are 0.793 and 0.681.

Active Sensor for Microwave Tissue Imaging with Bias-Switched Arrays.

Science.gov (United States)

Foroutan, Farzad; Nikolova, Natalia K

2018-05-06

A prototype of a bias-switched active sensor was developed and measured to establish the achievable dynamic range in a new generation of active arrays for microwave tissue imaging. The sensor integrates a printed slot antenna, a low-noise amplifier (LNA) and an active mixer in a single unit, which is sufficiently small to enable inter-sensor separation distance as small as 12 mm. The sensor’s input covers the bandwidth from 3 GHz to 7.5 GHz. Its output intermediate frequency (IF) is 30 MHz. The sensor is controlled by a simple bias-switching circuit, which switches ON and OFF the bias of the LNA and the mixer simultaneously. It was demonstrated experimentally that the dynamic range of the sensor, as determined by its ON and OFF states, is 109 dB and 118 dB at resolution bandwidths of 1 kHz and 100 Hz, respectively.

Ex vivo fluorescence confocal microscopy for fast evaluation of tumour margins during Mohs surgery.

Science.gov (United States)

Bennàssar, A; Vilata, A; Puig, S; Malvehy, J

2014-02-01

Ex vivo fluorescence confocal microscopy (FCM) enables real-time imaging of skin morphology directly in freshly excised tissue. FCM displays wide field-of-view mosaics with cellular resolution, thus enabling a rapid bedside pathology. An application of interest is rapid detection of residual basal cell carcinoma (BCC) in skin excisions during Mohs surgery. We sought to evaluate the sensitivity and specificity of ex vivo imaging with FCM for the detection of residual BCC in Mohs tissue excisions, and to calculate the time invested up to the diagnosis for both FCM and frozen sections. Eighty consecutive BCCs were prospectively collected and the margins scanned with ex vivo FCM, including excisions with and without residual BCC of all major subtypes. Each mosaic was divided into two or four, resulting in 480 submosaics for study. Every confocal submosaic was assessed for the presence or absence of BCC and compared with standard frozen sections as the gold standard. Furthermore, the time spent for each technique was calculated and compared. The overall sensitivity and specificity of detecting residual BCC were 88% and 99%, respectively. Moreover, the new technique reduced by almost two-thirds the time invested when compared with the processing of a frozen section (P confocal mosaicing microscopy in fresh tissue for rapid surgical pathology, potentially to expedite and guide Mohs surgery with high accuracy. This observation is an important step towards the goal of using real-time surgical pathology for skin tumours. © 2013 British Association of Dermatologists.

Design of a Compact Wideband Antenna Array for Microwave Imaging Applications

Directory of Open Access Journals (Sweden)

J. Puskely

2013-12-01

Full Text Available In the paper, wideband antenna arrays aimed at microwave imaging applications and SAR applications operating at Ka band were designed. The antenna array feeding network is realized by a low-loss SIW technology. Moreover, we have replaced the large feed network comprised of various T and Y junctions by a simple broadband network of compact size to more reduce losses in the substrate integrated waveguide and also save space on the PCB. The designed power 8-way divider is complemented by a wideband substrate integrated waveguide to a grounded coplanar waveguide transition and directly connected to the antenna elements. The measured results of antenna array are consistent with our simulation. Obtained results of the developed array demonstrated improvement compared to previously developed binary feed networks with microstrip or SIW splitters.

Microwave Imaging Reflectometry for the Measurement of Turbulent Fluctuations in Tokamaks

International Nuclear Information System (INIS)

Mazzucato, E.

2004-01-01

This article describes a numerical study of microwave reflectometry for the measurement of turbulent fluctuations in tokamak-like plasmas with a cylindrical geometry. Similarly to what was found previously in plane-stratified plasmas, the results indicate that the characteristics of density fluctuations cannot be uniquely determined from the reflected waves if the latter are allowed to propagate freely to the point of detection, as in standard reflectometry. Again, we find that if the amplitude of fluctuations is below a threshold that is set by the spectrum of poloidal wave numbers, the local characteristics of density fluctuations can be obtained from the phase of reflected waves when these are collected with a wide aperture antenna, and an image of the cutoff is formed onto an array of phase-sensitive detectors

Microwave detection of air showers with MIDAS

International Nuclear Information System (INIS)

Facal San Luis, P.; Alekotte, I.; Alvarez, J.; Berlin, A.; Bertou, X.; Bogdan, M.; Bohacova, M.; Bonifazi, C.; Carvalho, W.R.; Mello Neto, J.R.T. de; Genat, J.F.; Mills, E.; Monasor, M.; Privitera, P.; Reyes, I.C.; Rouille d’Orfeuil, B.

2012-01-01

MIDAS (MIcrowave Detector of Air Showers) is a prototype of a microwave telescope to detect extensive air showers: it images a 20 ° ×10 ° region of the sky with a 4.5 m parabolic reflector and 53 feeds in the focal plane. It has been commissioned in March 2010 and is currently taking data. We present the design, performance and first results of MIDAS.

Diffractive elements performance in chromatic confocal microscopy

International Nuclear Information System (INIS)

Garzon, J; Duque, D; Alean, A; Toledo, M; Meneses, J; Gharbi, T

2011-01-01

The Confocal Laser Scanning Microscopy (CLSM) has been widely used in the semiconductor industry and biomedicine because of its depth discrimination capability. Subsequent to this technique has been developed in recent years Chromatic Confocal Microscopy. This method retains the same principle of confocal and offers the added advantage of removing the axial movement of the moving system. This advantage is usually accomplished with an optical element that generates a longitudinal chromatic aberration and a coding system that relates the axial position of each point of the sample with the wavelength that is focused on each. The present paper shows the performance of compact chromatic confocal microscope when some different diffractive elements are used for generation of longitudinal chromatic aberration. Diffractive elements, according to the process and manufacturing parameters, may have different diffraction efficiency and focus a specific wavelength in a specific focal position. The performance assessment is carried out with various light sources which exhibit an incoherent behaviour and a broad spectral width.

A method for combining passive microwave and infrared rainfall observations

Science.gov (United States)

Kummerow, Christian; Giglio, Louis

1995-01-01

Because passive microwave instruments are confined to polar-orbiting satellites, rainfall estimates must interpolate across long time periods, during which no measurements are available. In this paper the authors discuss a technique that allows one to partially overcome the sampling limitations by using frequent infrared observations from geosynchronous platforms. To accomplish this, the technique compares all coincident microwave and infrared observations. From each coincident pair, the infrared temperature threshold is selected that corresponds to an area equal to the raining area observed in the microwave image. The mean conditional rainfall rate as determined from the microwave image is then assigned to pixels in the infrared image that are colder than the selected threshold. The calibration is also applied to a fixed threshold of 235 K for comparison with established infrared techniques. Once a calibration is determined, it is applied to all infrared images. Monthly accumulations for both methods are then obtained by summing rainfall from all available infrared images. Two examples are used to evaluate the performance of the technique. The first consists of a one-month period (February 1988) over Darwin, Australia, where good validation data are available from radar and rain gauges. For this case it was found that the technique approximately doubled the rain inferred by the microwave method alone and produced exceptional agreement with the validation data. The second example involved comparisons with atoll rain gauges in the western Pacific for June 1989. Results here are overshadowed by the fact that the hourly infrared estimates from established techniques, by themselves, produced very good correlations with the rain gauges. The calibration technique was not able to improve upon these results.

New algorithm to determine true colocalization in combination with image restoration and time-lapse confocal microscopy to MAP kinases in mitochondria.

Directory of Open Access Journals (Sweden)

Jorge Ignacio Villalta

Full Text Available The subcellular localization and physiological functions of biomolecules are closely related and thus it is crucial to precisely determine the distribution of different molecules inside the intracellular structures. This is frequently accomplished by fluorescence microscopy with well-characterized markers and posterior evaluation of the signal colocalization. Rigorous study of colocalization requires statistical analysis of the data, albeit yet no single technique has been established as a standard method. Indeed, the few methods currently available are only accurate in images with particular characteristics. Here, we introduce a new algorithm to automatically obtain the true colocalization between images that is suitable for a wide variety of biological situations. To proceed, the algorithm contemplates the individual contribution of each pixel's fluorescence intensity in a pair of images to the overall Pearsońs correlation and Manders' overlap coefficients. The accuracy and reliability of the algorithm was validated on both simulated and real images that reflected the characteristics of a range of biological samples. We used this algorithm in combination with image restoration by deconvolution and time-lapse confocal microscopy to address the localization of MEK1 in the mitochondria of different cell lines. Appraising the previously described behavior of Akt1 corroborated the reliability of the combined use of these techniques. Together, the present work provides a novel statistical approach to accurately and reliably determine the colocalization in a variety of biological images.

Real time diagnosis of bladder cancer with probe-based confocal laser endomicroscopy

Science.gov (United States)

Liu, Jen-Jane; Wu, Katherine; Adams, Winifred; Hsiao, Shelly T.; Mach, Kathleen E.; Beck, Andrew H.; Jensen, Kristin C.; Liao, Joseph C.

2011-02-01

Probe-based confocal laser endomicroscopy (pCLE) is an emerging technology for in vivo optical imaging of the urinary tract. Particularly for bladder cancer, real time optical biopsy of suspected lesions will likely lead to improved management of bladder cancer. With pCLE, micron scale resolution is achieved with sterilizable imaging probes (1.4 or 2.6 mm diameter), which are compatible with standard cystoscopes and resectoscopes. Based on our initial experience to date (n = 66 patients), we have demonstrated the safety profile of intravesical fluorescein administration and established objective diagnostic criteria to differentiate between normal, benign, and neoplastic urothelium. Confocal images of normal bladder showed organized layers of umbrella cells, intermediate cells, and lamina propria. Low grade bladder cancer is characterized by densely packed monomorphic cells with central fibrovascular cores, whereas high grade cancer consists of highly disorganized microarchitecture and pleomorphic cells with indistinct cell borders. Currently, we are conducting a diagnostic accuracy study of pCLE for bladder cancer diagnosis. Patients scheduled to undergo transurethral resection of bladder tumor are recruited. Patients undergo first white light cystocopy (WLC), followed by pCLE, and finally histologic confirmation of the resected tissues. The diagnostic accuracy is determined both in real time by the operative surgeon and offline after additional image processing. Using histology as the standard, the sensitivity, specificity, positive and negative predictive value of WLC and WLC + pCLE are calculated. With additional validation, pCLE may prove to be a valuable adjunct to WLC for real time diagnosis of bladder cancer.

Continuous microwave flow synthesis of mesoporous hydroxyapatite

International Nuclear Information System (INIS)

Akram, Muhammad; Alshemary, Ammar Z.; Goh, Yi-Fan; Wan Ibrahim, Wan Aini; Lintang, Hendrik O.; Hussain, Rafaqat

2015-01-01

We have successfully used continuous microwave flow synthesis (CMFS) technique for the template free synthesis of mesoporous hydroxyapatite. The continuous microwave flow reactor consisted of a modified 2.45 GHz household microwave, peristaltic pumps and a Teflon coil. This cost effective and efficient system was exploited to produce semi-crystalline phase pure nano-sized hydroxyapatite. Effect of microwave power, retention time and the concentration of reactants on the phase purity, degree of crystallinity and surface area of the final product was studied in detail. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to study the phase purity and composition of the product, while transmission electron microscopy (TEM) was used to study the effect of process parameters on the morphology of hydroxyapatite. The TEM analysis confirmed the formation of spherical particles at low microwave power; however the morphology of the particles changed to mesoporous needle and rod-like structure upon exposing the reaction mixture to higher microwave power and longer retention time inside the microwave. The in-vitro ion dissolution behavior of the as synthesized hydroxyapatite was studied by determining the amount of Ca 2+ ion released in SBF solution. - Highlights: • Continuous microwave flow synthesis method was used to prepare hydroxyapatite. • Increase in microwave power enhanced the degree of crystallinity. • TEM images confirmed the presence of mesopores on the surface of HA

Continuous microwave flow synthesis of mesoporous hydroxyapatite

Energy Technology Data Exchange (ETDEWEB)

Akram, Muhammad; Alshemary, Ammar Z.; Goh, Yi-Fan; Wan Ibrahim, Wan Aini [Department of Chemistry, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor (Malaysia); Lintang, Hendrik O. [Centre for Sustainable Nanomaterials (CSNano), Ibnu Sina Institute for Scientific and Industrial Research, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor (Malaysia); Hussain, Rafaqat, E-mail: rafaqat@kimia.fs.utm.my [Centre for Sustainable Nanomaterials (CSNano), Ibnu Sina Institute for Scientific and Industrial Research, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor (Malaysia)

2015-11-01

We have successfully used continuous microwave flow synthesis (CMFS) technique for the template free synthesis of mesoporous hydroxyapatite. The continuous microwave flow reactor consisted of a modified 2.45 GHz household microwave, peristaltic pumps and a Teflon coil. This cost effective and efficient system was exploited to produce semi-crystalline phase pure nano-sized hydroxyapatite. Effect of microwave power, retention time and the concentration of reactants on the phase purity, degree of crystallinity and surface area of the final product was studied in detail. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to study the phase purity and composition of the product, while transmission electron microscopy (TEM) was used to study the effect of process parameters on the morphology of hydroxyapatite. The TEM analysis confirmed the formation of spherical particles at low microwave power; however the morphology of the particles changed to mesoporous needle and rod-like structure upon exposing the reaction mixture to higher microwave power and longer retention time inside the microwave. The in-vitro ion dissolution behavior of the as synthesized hydroxyapatite was studied by determining the amount of Ca{sup 2+} ion released in SBF solution. - Highlights: • Continuous microwave flow synthesis method was used to prepare hydroxyapatite. • Increase in microwave power enhanced the degree of crystallinity. • TEM images confirmed the presence of mesopores on the surface of HA.

Microwave Synthesis of Nearly Monodisperse Core/Multishell Quantum Dots with Cell Imaging Applications

Directory of Open Access Journals (Sweden)

Xu Hengyi

2010-01-01

Full Text Available Abstract We report in this article the microwave synthesis of relatively monodisperse, highly crystalline CdSe quantum dots (QDs overcoated with Cd0.5Zn0.5S/ZnS multishells. The as-prepared QDs exhibited narrow photoluminescence bandwidth as the consequence of homogeneous size distribution and uniform crystallinity, which was confirmed by transmission electron microscopy. A high photoluminescence quantum yield up to 80% was measured for the core/multishell nanocrystals. Finally, the resulting CdSe/Cd0.5Zn0.5S/ZnS core/multishell QDs have been successfully applied to the labeling and imaging of breast cancer cells (SK-BR3.

Easy access to heterobimetallic complexes for medical imaging applications via microwave-enhanced cycloaddition

Directory of Open Access Journals (Sweden)

Nicolas Desbois

2015-11-01

Full Text Available The Cu(I-catalysed Huisgen cycloaddition, known as “click” reaction, has been applied to the synthesis of a range of triazole-linked porphyrin/corrole to DOTA/NOTA derivatives. Microwave irradiation significantly accelerates the reaction. The synthesis of heterobimetallic complexes was easily achieved in up to 60% isolated yield. Heterobimetallic complexes were easily prepared as potential MRI/PET (SPECT bimodal contrast agents incorporating one metal (Mn, Gd for the enhancement of contrast for MRI applications and one “cold” metal (Cu, Ga, In for future radionuclear imaging applications. Preliminary relaxivity measurements showed that the reported complexes are promising contrast agents (CA in MRI.

Monitoring pancreatic carcinogenesis by the molecular imaging of cathepsin E in vivo using confocal laser endomicroscopy.

Directory of Open Access Journals (Sweden)

Hui Li

Full Text Available The monitoring of pancreatic ductal adenocarcinoma (PDAC in high-risk populations is essential. Cathepsin E (CTSE is specifically and highly expressed in PDAC and pancreatic intraepithelial neoplasias (PanINs, and its expression gradually increases along with disease progression. In this study, we first established an in situ 7,12-dimethyl-1,2-benzanthracene (DMBA-induced rat model for PanINs and PDAC and then confirmed that tumorigenesis properties in this model were consistent with those of human PDAC in that CTSE expression gradually increased with tumor development using histology and immunohistochemistry. Then, using in vivo imaging of heterotopically implanted tumors generated from CTSE- overexpressing cells (PANC-1-CTSE in nude mice and in vitro imaging of PanINs and PDAC in DMBA-induced rats, the specificity of the synthesized CTSE-activatable probe was verified. Quantitative determination identified that the fluorescence signal ratio of pancreatic tumor to normal pancreas gradually increased in association with progressive pathological grades, with the exception of no significant difference between PanIN-II and PanIN-III grades. Finally, we monitored pancreatic carcinogenesis in vivo using confocal laser endomicroscopy (CLE in combination with the CTSE-activatable probe. A prospective double-blind control study was performed to evaluate the accuracy of this method in diagnosing PDAC and PanINs of all grades (>82.7%. This allowed us to establish effective diagnostic criteria for CLE in PDAC and PanINs to facilitate the monitoring of PDAC in high-risk populations.

Tapping mode microwave impedance microscopy

KAUST Repository

Lai, K.; Kundhikanjana, W.; Peng, H.; Cui, Y.; Kelly, M. A.; Shen, Z. X.

2009-01-01

We report tapping mode microwave impedance imaging based on atomic force microscope platforms. The shielded cantilever probe is critical to localize the tip-sample interaction near the tip apex. The modulated tip-sample impedance can be accurately

Signal and noise modeling in confocal laser scanning fluorescence microscopy.

Science.gov (United States)

Herberich, Gerlind; Windoffer, Reinhard; Leube, Rudolf E; Aach, Til

2012-01-01

Fluorescence confocal laser scanning microscopy (CLSM) has revolutionized imaging of subcellular structures in biomedical research by enabling the acquisition of 3D time-series of fluorescently-tagged proteins in living cells, hence forming the basis for an automated quantification of their morphological and dynamic characteristics. Due to the inherently weak fluorescence, CLSM images exhibit a low SNR. We present a novel model for the transfer of signal and noise in CLSM that is both theoretically sound as well as corroborated by a rigorous analysis of the pixel intensity statistics via measurement of the 3D noise power spectra, signal-dependence and distribution. Our model provides a better fit to the data than previously proposed models. Further, it forms the basis for (i) the simulation of the CLSM imaging process indispensable for the quantitative evaluation of CLSM image analysis algorithms, (ii) the application of Poisson denoising algorithms and (iii) the reconstruction of the fluorescence signal.

Confocal laser endomicroscopy

DEFF Research Database (Denmark)

Karstensen, John Gásdal; Săftoiu, Adrian; Brynskov, Jørn

2016-01-01

BACKGROUND AND STUDY AIMS: Confocal laser endomicroscopy (CLE) has been shown to predict relapse in ulcerative colitis in remission, but little is currently known about its role in Crohn's disease. The aim of this study was to identify reproducible CLE features in patients with Crohn's disease...

Microwave detection of air showers with MIDAS

Energy Technology Data Exchange (ETDEWEB)

Facal San Luis, P., E-mail: facal@kicp.uchicago.edu [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Alekotte, I. [Centro Atomico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), 8400 San Carlos de Bariloche, Rio Negro (Argentina); Alvarez, J. [Universidad de Santiago de Compostela, Departamento de Fisica de Particulas, Campus Sur, E-15782 Santiago de Compostela (Spain); Berlin, A. [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Bertou, X. [Centro Atomico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), 8400 San Carlos de Bariloche, Rio Negro (Argentina); Bogdan, M.; Bohacova, M. [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Bonifazi, C. [Univ. Federal do Rio de Janeiro (UFRJ), Instituto de Fisica, Cidade Universitaria, Caixa Postal 68528, 21945-970 Rio de Janeiro, RJ (Brazil); Carvalho, W.R. [Universidad de Santiago de Compostela, Departamento de Fisica de Particulas, Campus Sur, E-15782 Santiago de Compostela (Spain); Mello Neto, J.R.T. de [Univ. Federal do Rio de Janeiro (UFRJ), Instituto de Fisica, Cidade Universitaria, Caixa Postal 68528, 21945-970 Rio de Janeiro, RJ (Brazil); Genat, J.F.; Mills, E.; Monasor, M.; Privitera, P.; Reyes, I.C.; Rouille d& #x27; Orfeuil, B. [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); and others

2012-01-11

MIDAS (MIcrowave Detector of Air Showers) is a prototype of a microwave telescope to detect extensive air showers: it images a 20{sup Degree-Sign } Multiplication-Sign 10{sup Degree-Sign} region of the sky with a 4.5 m parabolic reflector and 53 feeds in the focal plane. It has been commissioned in March 2010 and is currently taking data. We present the design, performance and first results of MIDAS.

Methods for studying biofilm formation: flow cells and confocal laser scanning microscopy

DEFF Research Database (Denmark)

Tolker-Nielsen, Tim; Sternberg, Claus

2014-01-01

In this chapter methods for growing and analyzing biofilms under hydrodynamic conditions in flow cells are described. Use of flow cells allows for direct microscopic investigation of biofilm formation. The flow in these chambers is essentially laminar, which means that the biofilms can be grown u......, inoculation of the flow cells, running of the system, confocal laser scanning microscopy and image analysis, and disassembly and cleaning of the system....

Image-guided intraocular injection using multimodality optical coherence tomography and fluorescence confocal scanning laser ophthalmoscopy in rodent ophthalmological models

Science.gov (United States)

Terrones, Benjamin D.; Benavides, Oscar R.; Leeburg, Kelsey C.; Mehanathan, Sankarathi B.; Levine, Edward M.; Tao, Yuankai K.

2018-02-01

Intraocular injections are routinely performed for delivery of anti-VEGF and anti-inflammatory therapies in humans. While these injections are also performed in mice to develop novel models of ophthalmic diseases and screen novel therapeutics, the injection location and volume are not well-controlled and reproducible. We overcome limitations of conventional injections methods by developing a multimodality, long working distance, non-contact optical coherence tomography (OCT) and fluorescence confocal scanning laser ophthalmoscopy (cSLO) system for retinal imaging before and after injections. Our OCT+cSLO system combines a custom-built spectraldomain OCT engine (875+/-85 nm) with 125 kHz line-rate with a modified commercial cSLO with a maximum frame-rate of 30 fps (512 x 512 pix.). The system was designed for an overlapping OCT+cSLO field-of-view of 1.1 mm with a 7.76 mm working distance to the pupil. cSLO excitation light sources and filters were optimized for simultaneous GFP and tdTomato imaging. Lateral resolution was 3.02 µm for OCT and 2.74 μm for cSLO. Intravitreal injections of 5%, 10%, and 20% intralipid with Alex Fluor 488 were manually injected intraocularly in C57BL/6 mice. Post-injection imaging showed structural changes associated with retinal puncture, including the injection track, a retinal elevation, and detachment of the posterior hyaloid. OCT enables quantitative analysis of injection location and volumes whereas complementary cSLO improves specificity for identifying fluorescently labeled injected compounds and transgenic cells. The long working distance of our non-contact OCT+cSLO system is uniquely-suited for concurrent imaging with intraocular injections and may be applied for imaging of ophthalmic surgical dynamics and real-time image-guided injections.

Microwave imaging for conducting scatterers by hybrid particle swarm optimization with simulated annealing

International Nuclear Information System (INIS)

Mhamdi, B.; Grayaa, K.; Aguili, T.

2011-01-01

In this paper, a microwave imaging technique for reconstructing the shape of two-dimensional perfectly conducting scatterers by means of a stochastic optimization approach is investigated. Based on the boundary condition and the measured scattered field derived by transverse magnetic illuminations, a set of nonlinear integral equations is obtained and the imaging problem is reformulated in to an optimization problem. A hybrid approximation algorithm, called PSO-SA, is developed in this work to solve the scattering inverse problem. In the hybrid algorithm, particle swarm optimization (PSO) combines global search and local search for finding the optimal results assignment with reasonable time and simulated annealing (SA) uses certain probability to avoid being trapped in a local optimum. The hybrid approach elegantly combines the exploration ability of PSO with the exploitation ability of SA. Reconstruction results are compared with exact shapes of some conducting cylinders; and good agreements with the original shapes are observed.

The new images of the microwave sky: a concordance cosmology?

CERN Document Server

Bernardis, P D; Bock, J J; Bond, J R; Borrill, J; Boscaleri, A; Coble, K; Contaldi, C R; Crill, B P; De Gasperis, G; De Troia, G; Farese, P; Ganga, K; Giacometti, M; Hivon, E; Hristov, V V; Iacoangeli, A; Jaffe, A H; Jones, W C; Lange, A E; Martinis, L; Mason, P; Mauskopf, P D; Melchiorri, A; Montroy, T; Natoli, P; Netterfield, C B; Pascale, E; Piacentini, F; Pogosyan, D; Polenta, G; Pongetti, F; Prunet, S; Romeo, G; Ruhl, J E; Scaramuzzi, F; Vittorio, N

2002-01-01

The existence and anisotropy of the cosmic microwave background (CMB), the large scale distribution of Galaxies, the expansion of the Universe and the abundance of light elements can be all be explained with a single cosmological model. In this paper we focus on the CMB anisotropy maps produced by the BOOMERanG experiment and on their impact on cosmology. The images are consistent with the result of acoustic oscillations of the photons-matter plasma in the pre-recombination Universe (z > or approx. 1000). We show how the instrument and the observations have been optimized and how the basic parameters of the model are derived from the data. These observations of the CMB are gaussian and point to a low curvature Universe (omega approx 1), as expected in the inflation scenario. In order to fit these observations and other cosmological evidence, the composition of the Universe must have significant contributions from dark matter (omega sub m approx 0.3) and dark energy (omega subLAMBDA approx 0.7).

Conversion efficiency of implanted ions by confocal micro-luminescence mapping

International Nuclear Information System (INIS)

Deshko, Y.; Huang, Mengbing; Gorokhovsky, A.A.

2013-01-01

We report on the further development of the statistical approach to determine the conversion efficiency of implanted ions into emitting centers and present the measurement method based on the confocal micro-luminescence mapping. It involves the micro-luminescence mapping with a narrow-open confocal aperture, followed by the statistical analysis of the photoluminescence signal from an ensemble of emitting centers. The confocal mapping method has two important advantages compared to the recently discussed aperture-free method (J. Lumin. 131 (2011) 489): it is less sensitive to errors in the laser spot size and has a well defined useful area. The confocal mapping has been applied to the Xe center in diamond. The conversion efficiency has been found to be about 0.28, which is in good agreement with the results of the aperture-free method. - Highlights: ► Conversion efficiency of implanted ions into emitting centers – statistical approach. ► Micro-luminescence mapping with open and narrow confocal aperture – comparison. ► Advantages of the confocal micro-luminescence mapping. ► Confocal micro-luminescence mapping has been applied to the Xe center in diamond. ► The conversion efficiency has been found to be about 0.28.

Preparation of a Carbon Doped Tissue-Mimicking Material with High Dielectric Properties for Microwave Imaging Application

Directory of Open Access Journals (Sweden)

Siang-Wen Lan

2016-07-01

Full Text Available In this paper, the oil-in-gelatin based tissue-mimicking materials (TMMs doped with carbon based materials including carbon nanotube, graphene ink or lignin were prepared. The volume percent for gelatin based mixtures and oil based mixtures were both around 50%, and the doping amounts were 2 wt %, 4 wt %, and 6 wt %. The effect of doping material and amount on the microwave dielectric properties including dielectric constant and conductivity were investigated over an ultra-wide frequency range from 2 GHz to 20 GHz. The coaxial open-ended reflection technology was used to evaluate the microwave dielectric properties. Six measured values in different locations of each sample were averaged and the standard deviations of all the measured dielectric properties, including dielectric constant and conductivity, were less than one, indicating a good uniformity of the prepared samples. Without doping, the dielectric constant was equal to 23 ± 2 approximately. Results showed with doping of carbon based materials that the dielectric constant and conductivity both increased about 5% to 20%, and the increment was dependent on the doping amount. By proper selection of doping amount of the carbon based materials, the prepared material could map the required dielectric properties of special tissues. The proposed materials were suitable for the phantom used in the microwave medical imaging system.

Modeling of Fibrin Gels Based on Confocal Microscopy and Light-Scattering Data

Science.gov (United States)

Magatti, Davide; Molteni, Matteo; Cardinali, Barbara; Rocco, Mattia; Ferri, Fabio

2013-01-01

Fibrin gels are biological networks that play a fundamental role in blood coagulation and other patho/physiological processes, such as thrombosis and cancer. Electron and confocal microscopies show a collection of fibers that are relatively monodisperse in diameter, not uniformly distributed, and connected at nodal points with a branching order of ∼3–4. Although in the confocal images the hydrated fibers appear to be quite straight (mass fractal dimension Dm = 1), for the overall system 1confocal images, we developed a method to generate three-dimensional (3D) in silico gels made of cylindrical sticks of diameter d, density ρ, and average length 〈L〉, joined at randomly distributed nodal points. The resulting 3D network strikingly resembles real fibrin gels and can be sketched as an assembly of densely packed fractal blobs, i.e., regions of size ξ, where the fiber concentration is higher than average. The blobs are placed at a distance ξ0 between their centers of mass so that they are overlapped by a factor η = ξ/ξ0 and have Dm ∼1.2–1.6. The in silico gels’ structure is quantitatively analyzed by its 3D spatial correlation function g3D(r) and corresponding power spectrum I(q) = FFT3D[g3D(r)], from which ρ, d, Dm, η, and ξ0 can be extracted. In particular, ξ0 provides an excellent estimate of the gel mesh size. The in silico gels’ I(q) compares quite well with real gels’ elastic light-scattering measurements. We then derived an analytical form factor for accurately fitting the scattering data, which allowed us to directly recover the gels’ structural parameters. PMID:23473498

Optically sectioned in vivo imaging with speckle illumination HiLo microscopy

Science.gov (United States)

Lim, Daryl; Ford, Tim N.; Chu, Kengyeh K.; Mertz, Jerome

2011-01-01

We present a simple wide-field imaging technique, called HiLo microscopy, that is capable of producing optically sectioned images in real time, comparable in quality to confocal laser scanning microscopy. The technique is based on the fusion of two raw images, one acquired with speckle illumination and another with standard uniform illumination. The fusion can be numerically adjusted, using a single parameter, to produce optically sectioned images of varying thicknesses with the same raw data. Direct comparison between our HiLo microscope and a commercial confocal laser scanning microscope is made on the basis of sectioning strength and imaging performance. Specifically, we show that HiLo and confocal 3-D imaging of a GFP-labeled mouse brain hippocampus are comparable in quality. Moreover, HiLo microscopy is capable of faster, near video rate imaging over larger fields of view than attainable with standard confocal microscopes. The goal of this paper is to advertise the simplicity, robustness, and versatility of HiLo microscopy, which we highlight with in vivo imaging of common model organisms including planaria, C. elegans, and zebrafish.

Microwave imaging of a solar limb flare - Comparison of spectra and spatial geometry with hard X-rays

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