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Sample records for differential reflectance microscope

  1. Reflection Spectroscopy With The FT-IR Microscope

    NASA Astrophysics Data System (ADS)

    Wihlborg, William T.; Reffner, John A.; Strand, Scott W.; Wasacz, Frank M.

    1989-12-01

    The FT-IR microscope is a versatile sampling accessory used to record IR spectra in either transmittance or reflectance modes and capable of obtaining data from microscopic sampling areas. Because the FT-IR microscope simplifies the collection of reflectance data it has renewed interest in reflectance spectroscopy. Moreover, the ability to see the specific sample and to obtain spectra from small areas makes it possible to differentiate the mode of the reflection data. Reflections can be specular, diffuse or reflection-absorption modes. These modes are not independent, but the sample and its surface geometry can cause one mode to dominate all others. With polished grains or single crystal faces, specular reflection is the dominate mode. Thin films on metallic reflecting substrates make reflection-absorption the major reflection mode. Diffuse reflection dominates when the surface is very rough or fine irregular particles are analyzed. Since the sample can be seen with the microscope, the reflection mode can be predicted by direct observation of the sample's surface. In this work, examples of reflection spectral measurements are presented to illustrate the versatility of the FT-IR microscope. Of particular interest is the first report of quantitative analysis of a copolymer using specular reflectance measurements obtained with the FT-IR microscope. In this analysis, the Kramers-Kroenig transformation was used to obtain extinction (k) values. The k values derived from specular reflection are quantitative agreement with absorbance values measured by transmission.

  2. Differential magnetic force microscope imaging.

    PubMed

    Wang, Ying; Wang, Zuobin; Liu, Jinyun; Hou, Liwei

    2015-01-01

    This paper presents a method for differential magnetic force microscope imaging based on a two-pass scanning procedure to extract differential magnetic forces and eliminate or significantly reduce background forces with reversed tip magnetization. In the work, the difference of two scanned images with reversed tip magnetization was used to express the local magnetic forces. The magnetic sample was first scanned with a low lift distance between the MFM tip and the sample surface, and the magnetization direction of the probe was then changed after the first scan to perform the second scan. The differential magnetic force image was obtained through the subtraction of the two images from the two scans. The theoretical and experimental results have shown that the proposed method for differential magnetic force microscope imaging is able to reduce the effect of background or environment interference forces, and offers an improved image contrast and signal to noise ratio (SNR). © Wiley Periodicals, Inc.

  3. Dark-field illuminated reflectance fiber bundle endoscopic microscope

    NASA Astrophysics Data System (ADS)

    Liu, Xuan; Huang, Yong; Kang, Jin U.

    2011-04-01

    We propose a reflectance fiber bundle microscope using a dark-field illumination configuration for applications in endoscopic medical imaging and diagnostics. Our experiment results show that dark-field illumination can effectively suppress strong specular reflection from the proximal end of the fiber bundle. We realized a lateral resolution of 4.4 μm using the dark-field illuminated fiber bundle configuration. To demonstrate the feasibility of using the system to study cell morphology, we obtained still and video images of two thyroid cancer cell lines. Our results clearly allow differentiation of different cancer cell types.

  4. Image inpainting for the differential confocal microscope

    NASA Astrophysics Data System (ADS)

    Qiu, Lirong; Wang, Lei; Liu, Dali; Hou, Maosheng; Zhao, Weiqian

    2015-02-01

    In the process of zero-crossing trigger measurement of differential confocal microscope, the sample surface features or tilt will cause the edges can't be triggered. Meanwhile, environment vibration can also cause false triggering. In order to restore the invalid information of sample, and realize high-precision surface topography measurement, Total Variation (TV) inpainting model is applied to restore the scanning images. Emulation analysis and experimental verification of this method are investigated. The image inpainting algorithm based on TV model solves the minimization of the energy equation by calculus of variations, and it can effectively restore the non-textured image with noises. Using this algorithm, the simulation confocal laser intensity curve and height curve of standard step sample are restored. After inpainting the intensity curve below the threshold is repaired, the maximum deviation from ideal situation is 0.0042, the corresponding edge contour of height curve is restored, the maximum deviation is 0.1920, which proves the algorithm is effective. Experiment of grating inpainting indicates that the TV algorithm can restore the lost information caused by failed triggering and eliminate the noise caused by false triggering in zero-crossing trigger measurement of differential confocal microscope. The restored image is consistent with the scanning result of OLYMPUS confocal microscope, which can satisfy the request of follow-up measurement analysis.

  5. Reflection soft X-ray microscope and method

    DOEpatents

    Suckewer, S.; Skinner, C.H.; Rosser, R.

    1993-01-05

    A reflection soft X-ray microscope is provided by generating soft X-ray beams, condensing the X-ray beams to strike a surface of an object at a predetermined angle, and focusing the X-ray beams reflected from the surface onto a detector, for recording an image of the surface or near surface features of the object under observation.

  6. Reflection soft X-ray microscope and method

    DOEpatents

    Suckewer, Szymon; Skinner, Charles H.; Rosser, Roy

    1993-01-01

    A reflection soft X-ray microscope is provided by generating soft X-ray beams, condensing the X-ray beams to strike a surface of an object at a predetermined angle, and focusing the X-ray beams reflected from the surface onto a detector, for recording an image of the surface or near surface features of the object under observation.

  7. Modulation transfer function measurement of scanning reflectance microscopes.

    PubMed

    Wang, Zhao; Glazowski, Christopher E; Zavislan, James M

    2007-01-01

    Real-time medical imaging systems such as reflectance confocal microscopes and optical coherence microscopes are being tested in multiple-patient and multiple-center clinical trials. The modulation transfer function (MTF) of these systems at any given time influences the image information content and can affect the interpretation of the images. MTF is difficult to measure in real-time scanning systems when imaging at the Nyquist limit. We describe a measurement technique similar to the electronic imaging resolution standards ISO-12233 (electronic cameras) that can be applied to scanned spot imaging systems with asynchronous pixel clocks. This technique requires the acquisition of a single image of a reflective stripe object. An asynchronous pixel clock induces subpixel jitter in the edge location. The jitter is removed using a Fourier method, and an oversampled edge response function is calculated using algorithms developed in MATLAB. This technique provides fast, simple to use, and repeatable full-width at half maximum lateral resolution and MTF measurements based on only one test image. We present the results for reflectance confocal microscopes operating at 0.9 numerical aperture.

  8. Scanning differential polarization microscope: Its use to image linear and circular differential scattering

    SciTech Connect

    Mickols, W.; Maestre, M.F.

    1988-06-01

    A differential polarization microscope that couples the sensitivity of single-beam measurement of circular dichroism and circular differential scattering with the simultaneous measurement of linear dichroism and linear differential scattering has been developed. The microscope uses a scanning microscope stage and single-point illumination to give the very shallow depth of field found in confocal microscopy. This microscope can operate in the confocal mode as well as in the near confocal condition that can allow one to program the coherence and spatial resolution of the microscope. This microscope has been used to study the change in the structure of chromatin during the development of sperm in Drosophila.

  9. An Erbium Quantum Gas Microscope with a Reflective Objective

    NASA Astrophysics Data System (ADS)

    Krahn, Aaron; Phelps, Gregory; Hebert, Anne; Dickerson, Susannah; Greiner, Markus; Erbium Lab Team

    2016-05-01

    Dipolar atoms present an exciting opportunity to extend previous quantum gas microscope (QGM) experiments to more complex systems influenced by long range, anisotropic interactions. We present on current progress toward the construction of a QGM for ultracold Erbium atoms in an optical lattice, including the development of a novel imaging system for single-site resolution. While most QGMs until now have typically utilized a high numerical aperture microscope objective, we discuss a reflective mirror alternative that offers an equally high NA (.9-.95), a comparable field of view (34 micrometers radial), and a larger working distance (25 millimeters) that keeps the atoms far from any surfaces. By operating in a Schmidt telescope configuration, this imaging system is well-suited both for collecting 401 nm imaging fluorescence and for the creation of an expandable lattice with a variety of associated lattice geometries.

  10. [Identification of pearl powder using microscopic infrared reflectance spectroscopy].

    PubMed

    Zhang, Xuan; Hu, Chao; Yan, Yan; Yang, Hai-Feng; Li, Jun-Fang; Bai, Hua; Xi, Guang-Cheng; Liao, Jie

    2014-09-01

    Pearl is a precious ornament and traditional Chinese medicine, which application history in China is more than 2000 years. It is well known that the chemical ingredients of shell and pearl are very similar, which all of them including calcium carbonate and various amino acids. Generally, shell powders also can be used as medicine; however, its medicinal value is much lower than that of pearl powders. Due to the feature similarity between pearl powders and shell powders, the distinguishment of them by detecting chemical composition and morphology is very difficult. It should be noted that shell powders have been often posing as pearl powders in markets, which seriously infringes the interests of consumers. Identification of pearl powder was investigated by microscopic infrared reflectance spectroscopy, and pearl powder as well as shell powder was calcined at different temperatures for different time before infrared reflectance spectroscopy analysis. The experimental results indicated that when calcined at 400 °C for 30 minutes under atmospheric pressure, aragonite in pearl powder partly transformed into calcite, while aragonite in shell powder completely transformed into calcite. At the same time, the difference in phase transition between the pearl powders 'and shell powders can be easily detected by using the microscopic infrared reflectance spectroscopy. Therefore, based on the difference in their phase transition process, infrared reflectance spectroscopy can be used to identify phase transformation differences between pearl powder and shell powder. It's more meaningfully that the proposed infrared reflectance spec- troscopy method was also investigated for the applicability to other common counterfeits, such as oyster shell powders and abalone shell powders, and the results show that the method can be a simple, efficiently and accurately method for identification of pearl powder.

  11. Second-harmonic patterned polarization-analyzed reflection confocal microscope

    NASA Astrophysics Data System (ADS)

    Okoro, Chukwuemeka; Toussaint, Kimani C.

    2017-08-01

    We introduce the second-harmonic patterned polarization-analyzed reflection confocal (SPPARC) microscope-a multimodal imaging platform that integrates Mueller matrix polarimetry with reflection confocal and second-harmonic generation (SHG) microscopy. SPPARC microscopy provides label-free three-dimensional (3-D), SHG-patterned confocal images that lend themselves to spatially dependent, linear polarimetric analysis for extraction of rich polarization information based on the Mueller calculus. To demonstrate its capabilities, we use SPPARC microscopy to analyze both porcine tendon and ligament samples and find differences in both circular degree-of-polarization and depolarization parameters. Moreover, using the collagen-generated SHG signal as an endogenous counterstain, we show that the technique can be used to provide 3-D polarimetric information of the surrounding extrafibrillar matrix plus cells or EFMC region. The unique characteristics of SPPARC microscopy holds strong potential for it to more accurately and quantitatively describe microstructural changes in collagen-rich samples in three spatial dimensions.

  12. Development and evaluation of an automated reflectance microscope system for the petrographic characterization of bituminous coals

    SciTech Connect

    Hoover, D. S.; Davis, A.

    1980-10-01

    The development of automated coal petrographic techniques will lessen the demands on skilled personnel to do routine work. This project is concerned with the development and successful testing of an instrument which will meet these needs. The fundamental differences in reflectance of the three primary maceral groups should enable their differentiation in an automated-reflectance frequency histogram (reflectogram). Consequently, reflected light photometry was chosen as the method for automating coal petrographic analysis. Three generations of an automated system (called Rapid Scan Versions I, II and III) were developed and evaluated for petrographic analysis. Their basic design was that of a reflected-light microscope photometer with an automatic stage, interfaced with a minicomputer. The hardware elements used in the Rapid Scan Version I limited the system's flexibility and presented problems with signal digitization and measurement precision. Rapid Scan Version II was designed to incorporate a new microscope photometer and computer system. A digital stepping stage was incorporated into the Rapid Scan Version III system. The precision of reflectance determination of this system was found to be +- 0.02 percent reflectance. The limiting factor in quantitative interpretation of Rapid Scan reflectograms is the resolution of reflectance populations of the individual maceral groups. Statistical testing indicated that reflectograms were highly reproducible, and a new computer program, PETAN, was written to interpret the curves for vitrinite reflectance parameters ad petrographic.

  13. Pupil engineering for a confocal reflectance line-scanning microscope

    NASA Astrophysics Data System (ADS)

    Patel, Yogesh G.; Rajadhyaksha, Milind; DiMarzio, Charles A.

    2011-03-01

    Confocal reflectance microscopy may enable screening and diagnosis of skin cancers noninvasively and in real-time, as an adjunct to biopsy and pathology. Current confocal point-scanning systems are large, complex, and expensive. A confocal line-scanning microscope, utilizing a of linear array detector can be simpler, smaller, less expensive, and may accelerate the translation of confocal microscopy in clinical and surgical dermatology. A line scanner may be implemented with a divided-pupil, half used for transmission and half for detection, or with a full-pupil using a beamsplitter. The premise is that a confocal line-scanner with either a divided-pupil or a full-pupil will provide high resolution and optical sectioning that would be competitive to that of the standard confocal point-scanner. We have developed a confocal line-scanner that combines both divided-pupil and full-pupil configurations. This combined-pupil prototype is being evaluated to determine the advantages and limitations of each configuration for imaging skin, and comparison of performance to that of commercially available standard confocal point-scanning microscopes. With the combined configuration, experimental evaluation of line spread functions (LSFs), contrast, signal-to-noise ratio, and imaging performance is in progress under identical optical and skin conditions. Experimental comparisons between divided-pupil and full-pupil LSFs will be used to determine imaging performance. Both results will be compared to theoretical calculations using our previously reported Fourier analysis model and to the confocal point spread function (PSF). These results may lead to a simpler class of confocal reflectance scanning microscopes for clinical and surgical dermatology.

  14. Quantitative surface topography determination by Nomarski reflection microscopy. 2: Microscope modification, calibration, and planar sample experiments.

    PubMed

    Hartman, J S; Gordon, R L; Lessor, D L

    1980-09-01

    The application of reflective Nomarski differential interference contrast microscopy for the determination of quantitative sample topography data is presented. The discussion includes a review of key theoretical results presented previously plus the experimental implementation of the concepts using a commercial Nomarski microscope. The experimental work included the modification and characterization of a commercial microscope to allow its use for obtaining quantitative sample topography data. System usage for the measurement of slopes on flat planar samples is also discussed. The discussion has been designed to provide the theoretical basis, a physical insight, and a cookbook procedure for implementation to allow these results to be of value to both those interested in the microscope theory and its practical usage in the metallography laboratory.

  15. Differential phase acoustic microscope for micro-NDE

    NASA Technical Reports Server (NTRS)

    Waters, David D.; Pusateri, T. L.; Huang, S. R.

    1992-01-01

    A differential phase scanning acoustic microscope (DP-SAM) was developed, fabricated, and tested in this project. This includes the acoustic lens and transducers, driving and receiving electronics, scanning stage, scanning software, and display software. This DP-SAM can produce mechanically raster-scanned acoustic microscopic images of differential phase, differential amplitude, or amplitude of the time gated returned echoes of the samples. The differential phase and differential amplitude images provide better image contrast over the conventional amplitude images. A specially designed miniature dual beam lens was used to form two foci to obtain the differential phase and amplitude information of the echoes. High image resolution (1 micron) was achieved by applying high frequency (around 1 GHz) acoustic signals to the samples and placing two foci close to each other (1 micron). Tone burst was used in this system to obtain a good estimation of the phase differences between echoes from the two adjacent foci. The system can also be used to extract the V(z) acoustic signature. Since two acoustic beams and four receiving modes are available, there are 12 possible combinations to produce an image or a V(z) scan. This provides a unique feature of this system that none of the existing acoustic microscopic systems can provide for the micro-nondestructive evaluation applications. The entire system, including the lens, electronics, and scanning control software, has made a competitive industrial product for nondestructive material inspection and evaluation and has attracted interest from existing acoustic microscope manufacturers.

  16. Differentiated Coaching: Fostering Reflection with Teachers

    ERIC Educational Resources Information Center

    Stover, Katie; Kissel, Brian; Haag, Karen; Shoniker, Rebecca

    2011-01-01

    Literacy coaches inspire teacher reflection and promote a culture of ongoing professional learning. This article illustrates the role of literacy coaches, describes how coaches differentiate support for a diverse group of teachers, and explains how teacher reflection can be a catalyst for change and professional growth. The authors, current and…

  17. Differentiated Coaching: Fostering Reflection with Teachers

    ERIC Educational Resources Information Center

    Stover, Katie; Kissel, Brian; Haag, Karen; Shoniker, Rebecca

    2011-01-01

    Literacy coaches inspire teacher reflection and promote a culture of ongoing professional learning. This article illustrates the role of literacy coaches, describes how coaches differentiate support for a diverse group of teachers, and explains how teacher reflection can be a catalyst for change and professional growth. The authors, current and…

  18. Dermoscopic and reflectance confocal microscopic presentation of Hailey-Hailey disease: A case series.

    PubMed

    Oliveira, A; Arzberger, E; Pimentel, B; de Sousa, V C; Leal-Filipe, P

    2017-08-07

    Hailey-Hailey disease is a rare inherited acantholytic skin disorder characterized by heterogeneous clinical presentation. Its differential diagnosis might be wide, including other genodermatoses, inflammatory, and infectious skin diseases. Although histopathology remains as diagnostic gold standard, noninvasive techniques such as dermoscopy and reflectance confocal microscopy may assist clinical examination. Herein, we aim to further characterize the dermoscopic and reflectance confocal microscopic presentation of Hailey-Hailey disease with histologic correlation. Eight patients with Hailey-Hailey disease were consecutively recruited. All patients were examined using dermoscopy and reflectance confocal microscopy. In all cases, dermoscopy enabled the visualization of polymorphous vessels, including glomerular and linear-looped vessels, within a pink-whitish background. Reflectance confocal microscopy revealed wide suprabasilar partial acantholysis and clefting, crusts, dilated papillae with tortuous vessels, and inflammatory cells. Dyskeratosis, uplocated papillae, and adnexal sparing were also observed. Although definite diagnosis was obtained by histopathology in all cases, dermoscopy and reflectance confocal microscopy allowed the identification of common features (even in cases with dissimilar clinical presentation) that may support an early diagnosis of Hailey-Hailey disease, and its differentiation from other more frequent skin disorders. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Soft tissue differentiation by diffuse reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Zam, Azhar; Stelzle, Florian; Nkenke, Emeka; Tangermann-Gerk, Katja; Schmidt, Michael; Adler, Werner; Douplik, Alexandre

    2009-07-01

    Laser surgery gives the possibility to work remotely which leads to high precision, little trauma and high level sterility. However these advantages are coming with the lack of haptic feedback during the laser ablation of tissue. Therefore additional means are required to control tissue-specific ablation during laser surgery supporting the surgeon regardless of experience and skills. Diffuse Reflectance Spectroscopy provides a straightforward and simple approach for optical tissue differentiation. We measured diffuse reflectance from four various tissue types ex vivo. We applied Linear Discriminant Analysis (LDA) to differentiate the four tissue types and computed the area under the ROC curve (AUC). Special emphasis was taken on the identification of nerve as the most crucial tissue for maxillofacial surgery. The results show a promise for differentiating soft tissues as guidance for tissue-specific laser surgery by means of the diffuse reflectance.

  20. Design of reflectance confocal microscopes for clinical applications

    NASA Astrophysics Data System (ADS)

    Zavislan, James M.

    2009-02-01

    Reflectance confocal microscopy provides real time, cellular resolution images of in-vivo and ex-vivo tissues and has been cleared by the FDA and international regulatory agencies for medical applications. Clinical applications of reflectance confocal microscopy are being tested in single- and multi-center clinical trials. In this paper I will review the design challenges of sub-surface imaging with confocal microscopy and techniques to compare the instruments performance between different sites.

  1. Measurement of a damaged layer thickness with reflection acoustic microscope.

    PubMed

    Ishikawa, I; Kanda, H; Katakura, K; Semba, T

    1989-01-01

    An acoustic microscope was used for determining the frequency dependence of surface acoustic wave (SAW) velocity on a specimen whose silicon single-crystal surface was machined under various conditions. Consequently, thickness of the damaged layers could be estimated from the curvature points of frequency dispersion curves of the SAW velocity. It was revealed that thicknesses of the damaged layers can be estimated through rough approximation by about one-half the wavelength determined by the frequency at curvature points. From specimens possessing two damaged layers, frequency dispersion curves with two curvature lines can be obtained. From the curvature point at high frequencies the thickness of the top damaged layer can be determined. On the other hand, from the curvature point at low frequencies, the thickness of the inner damaged layer can also be determined. By choosing an acoustic lens as the condition for exciting SAWs, images can be observed while varying the frequency. From observation results obtained with this method, the distribution in the depth direction can be clarified.

  2. DESIGN NOTE: Surface microscopy and fibre characterization using a multimode-fibre reflectance microscope

    NASA Astrophysics Data System (ADS)

    Lukins, P. B.; Rehman, S.; Stevens, G. B.

    2000-04-01

    A remarkably simple scanning infrared surface-reflectance microscope based on a multimode-fibre-coupled diode laser together with straightforward electronics and scanning stage is described. The design does not require alignment and completely avoids the use of objectives, beamsplitters and other optics normally associated with such microscopes. The axial response, resolution and imaging properties for non-interferometric operation are characterized. A geometric model for the transmission of such a microscope using an idealized step/graded-index multimode fibre is presented. This model is used to explain the axial response of the microscope. Finally, a new method for determination of the numerical aperture and index-grading parameter of multimode fibres is proposed. This method is based on the geometric model together with axial-response measurements using the microscope in such a way that the fibre probe is the actual test fibre.

  3. Molecular differential diagnosis of renal carcinoma: from microscopes to microsatellites.

    PubMed

    Steiner, G; Sidransky, D

    1996-12-01

    In the last decade, specific chromosomal alterations have been associated with different tumor types. These aberrations were originally detected by karyotyping and then by more sophisticated cytogenetic analysis. A few karyotypic alterations can be directly linked to distinct malignancies, such as the Philadelphia chromosome in acute lymphoblastic leukemia, loss of distal chromosome 3p 14 in small-cell lung cancer, the loss of distal chromosome 11p13 in Wilms' tumor, and loss or rearrangement of the short arm of chromosome 3 in clear and chromophobe RCC. The relative specificity of the latter findings enabled investigators to diagnose an occult renal clear-cell carcinoma from a supraclavicular lymph node metastasis by analysis of G-banded metaphase chromosomes obtained from this mass. A similar report based also on cytogenetic findings was published earlier. Karyotypic changes, however, detect only gross alterations visible to an observer. With more refined diagnostic tools, such as microsatellite analysis, other, even smaller, well defined lesions can be analyzed. A summary of the known frequencies of chromosomal losses is given in Table 1. The combination of certain LOH patterns has shown great promise in the differential diagnosis of renal tumors. The transfer of molecular genetics from the laboratory to surgical pathology and other clinical departments is a meaningful event and a challenging task. Molecular pathology is certain to become important in the diagnosis of tumors with unclear histology. Diagnosis based widely upon staining techniques and determination of a patient's prognosis by staging and grading alone will be increasingly accompanied by molecular genetic methods. Pathology may be on the verge of the greatest change since the introduction of the microscope.

  4. Reflection Imaging X-Ray Laser Microscope (RIXRALM) and its biological applications. Progress report

    SciTech Connect

    Suckewer, S.

    1998-07-01

    The main stimulus for the development of the proposed microscope (RIXRALM) is the possibility to view the surface and near surface structure of biological materials, such as cell membranes at much higher resolution than an optical (confocal) microscope. Although the prediction resolution of RIXRALM was lower than a Scanning Electron Microscope (SEM), the possibility to obtain images of cells (membranes) in a more natural, hydrated state and, in many cases, without staining, made the idea of a reflection X-ray microscope very attractive. The specimen can be in an H{sub 2}O saturated He atmosphere at atmospheric pressure. As the image can be obtained quickly (nsec exposure, occurring within seconds of insertion into such an environment), the cell surface can be seen in a state which is very close to its natural condition. Besides, the short exposure time eliminates the effect of motional blurring on the images. Their X-ray reflection microscope fit well in the very large gap in the size of biological objects studied in light microscopy (sub-micron size) and electron microscope (down to a few nanometers size).

  5. Full-field transmission-type angle-deviation optical microscope with reflectivity-height transformation

    PubMed Central

    Chiu, Ming-Hung; Tan, Chen-Tai; Tsai, Ming-Hung; Yang, Ya-Hsin

    2015-01-01

    This full-field transmission-type three-dimensional (3D) optical microscope is constructed based on the angle deviation method (ADM) and the algorithm of reflectivity-height transformation (RHT). The surface height is proportional to the deviation angle of light passing through the object. The angle deviation and surface height can be measured based on the reflectivity closed to the critical angle using a parallelogram prism and two CCDs. PMID:26504645

  6. Full-field transmission-type angle-deviation optical microscope with reflectivity-height transformation.

    PubMed

    Chiu, Ming-Hung; Tan, Chen-Tai; Tsai, Ming-Hung; Yang, Ya-Hsin

    2015-10-01

    This full-field transmission-type three-dimensional (3D) optical microscope is constructed based on the angle deviation method (ADM) and the algorithm of reflectivity-height transformation (RHT). The surface height is proportional to the deviation angle of light passing through the object. The angle deviation and surface height can be measured based on the reflectivity closed to the critical angle using a parallelogram prism and two CCDs.

  7. Development of in vivo confocal microscope for reflection and fluorescence imaging simultaneously

    NASA Astrophysics Data System (ADS)

    Ahn, MyoungKi; Chun, ByungSeon; Song, Cheol; Gweon, DaeGab

    2010-02-01

    In-vivo confocal microscope technology can be applied to the medical imaging diagnosis and new drug development. We present an in-vivo confocal microscope that can acquire a reflection image and a fluorescence image simultaneously and independently. To obtain reflection confocal images, we used a linearly polarized diode laser with the wavelength of 830 nm. To acquire fluorescence confocal images, we used two diode lasers with the wavelength of 488 nm and 660 nm, respectively. Because of a broad wavelength bandwidth from visible (488 nm) to near-IR (830 nm), we designed and optimized the optical system to reduce various optical aberrations. With the developed in-vivo confocal microscope, we performed ex-vivo cell imaging and in-vivo imaging of the human skin.

  8. Nonscanning three-dimensional optical microscope based on the reflectivity-height transformation for biological measurements.

    PubMed

    Chiu, Ming-Hung; Tan, Chen-Tai; Lee, Tsuan-Shih; Lee, Jain-Cheng

    2013-04-01

    We propose a nonscanning three-dimensional (3D) optical microscope based on reflectivity-height transformation in applications of biological and transparent plate measurements. The reflectivity of a prism can be transformed to the surface height of the specimen based on geometrical optics and the principle of internal reflection. Thus, the pattern of reflectivity is representative of the surface profile. Using charge-coupled device cameras to obtain the two-dimensional image patterns and combining with its reflectivity pattern, the 3D profile can be generated. The lateral resolution is determined by the diffraction limit, and the vertical resolution is better than several nanometers according to the incident angle and polarization used.

  9. A Reflective Nonlinear Acoustic Microscope to Contour the Quantitative Adhesion at a Bonded Solid-Solid Interface

    NASA Astrophysics Data System (ADS)

    Chen, Jian-Jun; Zhang, De; Liu, Xiao-Zhou

    2014-09-01

    We set up a reflective nonlinear acoustic microscope to contour the quantitative adhesion at a bonded solid-solid interface by a contact acoustic nonlinearity (CAN) method. The principle of the reflective nonlinear acoustic microscope is described. After the vibration amplitude of the incident, focusing wave at the bonded interface is calculated, the standard adhesion with a complete bonding state is established by the tension test, the reflective CAN parameter is calibrated, and the quantitative contour of the adhesion at the interface can be obtained. The experimental contours of two samples are also presented. Compared with the transmitted microscope, the reflective one is more convenient and more suitable for practical applications.

  10. An Introduction to Differentials Based on Hyperreal Numbers and Infinite Microscopes

    ERIC Educational Resources Information Center

    Henry, Valerie

    2010-01-01

    In this article, we propose to introduce the differential of a function through a non-classical way, lying on hyperreals and infinite microscopes. This approach is based on the developments of nonstandard analysis, wants to be more intuitive than the classical one and tries to emphasize the functional and geometric aspects of the differential. In…

  11. An Introduction to Differentials Based on Hyperreal Numbers and Infinite Microscopes

    ERIC Educational Resources Information Center

    Henry, Valerie

    2010-01-01

    In this article, we propose to introduce the differential of a function through a non-classical way, lying on hyperreals and infinite microscopes. This approach is based on the developments of nonstandard analysis, wants to be more intuitive than the classical one and tries to emphasize the functional and geometric aspects of the differential. In…

  12. Evaluation of an Automated Reflectance Microscope system for coal characterization. Technical report 18

    SciTech Connect

    Liscinsky, D. S.; Vastola, F.

    1980-01-01

    The potential of an Automated Reflectance Microscope (ARM) system to determine the petrographic composition of a coal has been examined. The analysis involves the automatic scanning of a polished coal surface with a reflectance microscope. The reflectivity of consecutive 4-square-micrometer spots on the surface is measured by a photomultiplier tube and recorded by a microcomputer. This study was aimed at making the interpretation of a reflectogram more straightforward, that is, increasing the ability to discriminate among species. Although hardware improvements to decrease the spot size and the error associated with each reading would allow some increase in the ability to discriminate among species, the heterogeneous nature of the surface still limits the qualitative and quantitative information that can be derived from a reflectogram. Therefore a real-time data processing algorithm was implemented during data acquisition to study the effects that processing can have on a reflectogram. By measuring connectivity, it was found that edge readings could be indirectly eliminated. This greatly improved the ability to discriminate among species. Further investigation led to the conclusion that physical particle size has a major effect on a reflectogram. The concentration of coal in a pellet also has an effect on the ability to discriminate among species. A bonus of using processing to enhance the data was the ability to simultaneously gather information on particle size distributions. Based on the results the potential of an ARM system is improved by algorithm enhancement. The processing of the data allows some of the inherent limitations to be reduced.

  13. Microscopic theory for negative differential mobility in crowded environments.

    PubMed

    Bénichou, O; Illien, P; Oshanin, G; Sarracino, A; Voituriez, R

    2014-12-31

    We study the behavior of the stationary velocity of a driven particle in an environment of mobile hard-core obstacles. Based on a lattice gas model, we demonstrate analytically that the drift velocity can exhibit a nonmonotonic dependence on the applied force, and show quantitatively that such negative differential mobility (NDM), observed in various physical contexts, is controlled by both the density and diffusion time scale of the obstacles. Our study unifies recent numerical and analytical results obtained in specific regimes, and makes it possible to determine analytically the region of the full parameter space where NDM occurs. These results suggest that NDM could be a generic feature of biased (or active) transport in crowded environments.

  14. Direct numerical simulations of magmatic differentiation at the microscopic scale

    NASA Astrophysics Data System (ADS)

    Sethian, J.; Suckale, J.; Elkins-Tanton, L. T.

    2010-12-01

    A key question in the context of magmatic differentiation and fractional crystallization is the ability of crystals to decouple from the ambient fluid and sink or rise. Field data indicates a complex spectrum of behavior ranging from rapid sedimentation to continued entrainment. Theoretical and laboratory studies paint a similarly rich picture. The goal of this study is to provide a detailed numerical assessment of the competing effects of sedimentation and entrainment at the scale of individual crystals. The decision to simulate magmatic differentiation at the grain scale comes at the price of not being able to simultaneously solve for the convective velocity field at the macroscopic scale, but has the crucial advantage of enabling us to fully resolve the dynamics of the systems from first principles without requiring any simplifying assumptions. The numerical approach used in this study is a customized computational methodology developed specifically for simulations of solid-fluid coupling in geophysical systems. The algorithm relies on a two-step projection scheme: In the first step, we solve the multiple-phase Navier-Stokes or Stokes equation in both domains. In the second step, we project the velocity field in the solid domain onto a rigid-body motion by enforcing that the deformation tensor in the respective domain is zero. This procedure is also used to enforce the no-slip boundary-condition on the solid-fluid interface. We have extensively validated and benchmarked the method. Our preliminary results indicate that, not unexpectedly, the competing effects of sedimentation and entrainment depend sensitively on the size distribution of the crystals, the aspect ratio of individual crystals and the vigor of the ambient flow field. We provide a detailed scaling analysis and quantify our results in terms of the relevant non-dimensional numbers.

  15. Design and construction of a multiwavelength, micromirror total internal reflectance fluorescence microscope.

    PubMed

    Larson, Joshua; Kirk, Matt; Drier, Eric A; O'Brien, William; MacKay, James F; Friedman, Larry J; Hoskins, Aaron A

    2014-10-01

    Colocalization single-molecule spectroscopy (CoSMoS) has proven to be a useful method for studying the composition, kinetics and mechanisms of complex cellular machines. Key to the technique is the ability to simultaneously monitor multiple proteins and/or nucleic acids as they interact with one another. Here we describe a protocol for constructing a CoSMoS micromirror total internal reflection fluorescence microscope (mmTIRFM). Design and construction of a scientific microscope often requires a number of custom components and a substantial time commitment. In our protocol, we have streamlined this process by implementation of a commercially available microscopy platform designed to accommodate the optical components necessary for an mmTIRFM. The mmTIRF system eliminates the need for machining custom parts by the end user and facilitates optical alignment. Depending on the experience level of the microscope builder, these time savings and the following protocol can enable mmTIRF construction to be completed within 2 months.

  16. Design and Construction of a Multi-wavelength, Micromirror Total Internal Reflectance Fluorescence Microscope

    PubMed Central

    Larson, Joshua; Kirk, Matt; Drier, Eric A.; O’Brien, William; MacKay, James F.; Friedman, Larry; Hoskins, Aaron

    2015-01-01

    Colocalization Single Molecule Spectroscopy (CoSMoS) has proven to be a useful method for studying the composition, kinetics, and mechanisms of complex cellular machines. Key to the technique is the ability to simultaneously monitor multiple proteins and/or nucleic acids as they interact with one another. Here we describe a protocol for constructing a CoSMoS micromirror Total Internal Reflection Fluorescence Microscope (mmTIRFM). Design and construction of a scientific microscope often requires a number of custom components and a significant time commitment. In our protocol, we have streamlined this process by implementation of a commercially available microscopy platform designed to accommodate the optical components necessary for a mmTIRFM. The mmTIRF system eliminates the need for machining custom parts by the end-user and facilitates optical alignment. Depending on the experience-level of the microscope builder, these time-savings and the following protocol can enable mmTIRF construction to be completed within two months. PMID:25188633

  17. Differential Microscopic Mobility of Components within a Deep Eutectic Solvent.

    PubMed

    Wagle, Durgesh V; Baker, Gary A; Mamontov, Eugene

    2015-08-06

    From macroscopic measurements of deep eutectic solvents such as glyceline (1:2 molar ratio of choline chloride to glycerol), the long-range translational diffusion of the larger cation (choline) is known to be slower compared to that of the smaller hydrogen bond donor (glycerol). However, when the diffusion dynamics are analyzed on the subnanometer length scale, we find that the displacements associated with the localized diffusive motions are actually larger for choline. This counterintuitive diffusive behavior can be understood as follows. The localized diffusive motions confined in the transient cage of neighbor particles, which precede the cage-breaking long-range diffusion jumps, are more spatially constrained for glycerol than for choline because of the stronger hydrogen bonds the former makes with chloride anions. The implications of such differential localized mobility of the constituents should be especially important for applications where deep eutectic solvents are confined on the nanometer length scale and their long-range translational diffusion is strongly inhibited (e.g., within microporous media).

  18. Differential Microscopic Mobility of Components within a Deep Eutectic Solvent

    DOE PAGES

    Wagle, Durgesh V.; Baker, Gary A.; Mamontov, Eugene

    2015-07-13

    From macroscopic measurements of deep eutectic solvents such as glyceline (1:2 molar ratio of choline chloride to glycerol), the long-range translational diffusion of the larger cation (choline) is known to be slower compared to that of the smaller hydrogen bond donor (glycerol). However, when the diffusion dynamics are analyzed on the subnanometer length scale, we discover that the displacements associated with the localized diffusive motions are actually larger for choline. This counterintuitive diffusive behavior can be understood as follows. The localized diffusive motions confined in the transient cage of neighbor particles, which precede the cage-breaking long-range diffusion jumps, are moremore » spatially constrained for glycerol than for choline because of the stronger hydrogen bonds the former makes with chloride anions. The implications of differential localized mobility of the constituents should be especially important for applications where deep eutectic solvents are confined on the nanometer length scale and their long-range translational diffusion is strongly inhibited (e.g., within microporous media).« less

  19. Differential Microscopic Mobility of Components within a Deep Eutectic Solvent

    SciTech Connect

    Wagle, Durgesh V.; Baker, Gary A.; Mamontov, Eugene

    2015-07-13

    From macroscopic measurements of deep eutectic solvents such as glyceline (1:2 molar ratio of choline chloride to glycerol), the long-range translational diffusion of the larger cation (choline) is known to be slower compared to that of the smaller hydrogen bond donor (glycerol). However, when the diffusion dynamics are analyzed on the subnanometer length scale, we discover that the displacements associated with the localized diffusive motions are actually larger for choline. This counterintuitive diffusive behavior can be understood as follows. The localized diffusive motions confined in the transient cage of neighbor particles, which precede the cage-breaking long-range diffusion jumps, are more spatially constrained for glycerol than for choline because of the stronger hydrogen bonds the former makes with chloride anions. The implications of differential localized mobility of the constituents should be especially important for applications where deep eutectic solvents are confined on the nanometer length scale and their long-range translational diffusion is strongly inhibited (e.g., within microporous media).

  20. Differential phase microscope and micro-tomography with a Foucault knife-edge scanning filter

    NASA Astrophysics Data System (ADS)

    Watanabe, N.; Hashizume, J.; Goto, M.; Yamaguchi, M.; Tsujimura, T.; Aoki, S.

    2013-10-01

    An x-ray differential phase microscope with a Foucault knife-edge scanning filter was set up at the bending magnet source BL3C, Photon Factory. A reconstructed phase profile from the differential phase image of an aluminium wire at 5.36 keV was fairly good agreement with the numerical simulation. Phase tomography of a biological specimen, such as an Artemia cyst, could be successfully demonstrated.

  1. Confocal reflectance quantitative phase microscope system for cellular membranes dynamics study (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Singh, Vijay Raj; Yaqoob, Zahid; So, Peter T. C.

    2017-02-01

    Quantitative phase microscopy (QPM) techniques developed so far primarily belongs to high speed transmitted light based systems that has enough sensitivity to resolve membrane fluctuations and dynamics, but has no depth resolution. Therefore, most biomechanics studies using QPM today is confined to simple cells, such as RBCs, without internal organelles. An important instrument that will greatly extend the biomedical applications of QPM is to develop next generation microscope with 3D capability and sufficient temporal resolution to study biomechanics of complex eukaryotic cells including the mechanics of their internal compartments. For eukaryotic cells, the depth sectioning capability is critical and should be sufficient to distinguish nucleic membrane fluctuations from plasma membrane fluctuations. Further, this microscope must provide high temporal resolution since typical eukaryotes membranes are substantially stiffer than RBCs. A confocal reflectance quantitative phase microscope is presented based on multi-pinhole scanning, with the capabilities of higher temporal resolution and sensitivity for nucleic and plasma membranes of eukaryotic cells. System hardware is developed based on an array of confocal pinhole generated by using the `ON' state of subset of micro-mirrors of digital micro-mirror device (DMD, from Texas Instruments) and high-speed raster scanning provides 14ms imaging speed in wide-field mode. A common path interferometer is integrated at the imaging arm for detection of specimens' quantitative phase information. Theoretical investigation of quantitative phase reconstructed from system is investigated and application of system is presented for dimensional fluctuations measurements of both cellular plasma and nucleic membranes of embryonic stem cells.

  2. A robust estimator of rainfall rate using differential reflectivity

    NASA Technical Reports Server (NTRS)

    Gorgucci, Eugenio; Scarchilli, Gianfranco; Chandrasekar, V.

    1994-01-01

    Conventional estimator of rainfall rate using reflectivity factor and differential reflectivity Z(sub DR) becomes unstable when the measured values of Z(sub DR) are small due to measurement errors. An alternate estimator of rainfall rate using reflectivity factor and Z(sub DR) is derived, so that this estimator is fairly robust over the full dynamic range of reflectivity factor and Z(sub DR). Simulations are used to study the error structure of this robust estimator in comparison with the conventional estimator of rainfall rate. It is shown that the alternate estimator performs better than the conventional estimator of rainfall rate at all rainfall values. In particular the largest improvement of this estimator is proved to be in light rain. The robust estimator is obtained as a direct regression of rainfall rate against reflectivity factor and Z(sub DR) instead of solving for the drop size distribution.

  3. High numerical aperture microendoscope objective for a fiber confocal reflectance microscope

    NASA Astrophysics Data System (ADS)

    Kester, Robert T.; Tkaczyk, Tomasz S.; Descour, Michael R.; Christenson, Todd; Richards-Kortum, Rebecca

    2007-03-01

    A disposable high numerical aperture microendoscope objective has been designed, fabricated, and tested for use with a fiber confocal reflectance microscope. The objective uses high precision LIGA fabricated components to integrate imaging components and hydraulic suction lines into a housing that measures only 3.85 mm in outer diameter and 14.65 mm in length. The hydraulics are used to translate tissue through the focal plane for three dimensional imaging. This device is diffraction limited for λ = 850 nm, has a numerical aperture of 1.0, a field of view of 250 µm, and a working distance of 450 µm. The objective is intended for in vivo imaging of precancerous cells.

  4. Reflection electron energy-loss spectroscopy and imaging for surface studies in transmission electron microscopes.

    PubMed

    Wang, Z L; Bentley, J

    1992-02-15

    A review is given on the techniques and applications of high-energy reflection electron energy-loss spectroscopy (REELS) and reflection electron microscopy (REM) for surface studies in scanning transmission electron microscopes (STEM) and conventional transmission electron microscopes (TEM). A diffraction method is introduced to identify a surface orientation in the geometry of REM. The surface dielectric response theory is presented and applied for studying alpha-alumina surfaces. Domains of the alpha-alumina (012) surface initially terminated with oxygen can be reduced by an intense electron beam to produce Al metal; the resistance to beam damage of surface domains initially terminated with Al+3 ions is attributed to the screening effect of adsorbed oxygen. Surface energy-loss near-edge structure (ELNES), extended energy-loss fine structure (EXELFS), and microanalysis using REELS are illustrated based on the studies of TiO2 and MgO. Effects of surface resonances (or channeling) on the REELS signal-to-background ratio are described. The REELS detection of a monolayer of oxygen adsorption on diamond (111) surfaces is reported. It is shown that phase contrast REM image content can be significantly increased with the use of a field emission gun (FEG). Phase contrast effects close to the core of a screw dislocation are discussed and the associated Fresnel fringes around a surface step are observed. Finally, an in situ REM experiment is described for studying atomic desorption and diffusion processes on alpha-alumina surfaces at temperatures of 1,300-1,400 degrees C.

  5. A multipurpose scanning near-field optical microscope: Reflectivity and photocurrent on semiconductor and biological samples

    NASA Astrophysics Data System (ADS)

    Cricenti, A.; Generosi, R.; Barchesi, C.; Luce, M.; Rinaldi, M.

    1998-09-01

    A multipurpose scanning near field optical microscope (SNOM) operating at ambient pressure is described with the aim of characterizing the inner parts of biological molecules and any semiconductor or metal microstructure. Therefore, in addition to the requirements of reliability and mechanical stability we have carefully considered analyzing a sample with all available geometries for input/output of photons, in order to get as much information as possible. The SNOM unit consists of two separable cylindrical supports; the lower one contains the sample holder mounted on top of a piezoelectric scanner which is contained in a motor controlled x-y-z stage. A piezo-modulated stretched optical fiber with a few tens of nanometer pinhole and a shear-force apparatus mounted inside the top cylinder allow for topography measurements. The reflectivity of the sample can be measured by applying different methods: the sample can be illuminated on top by an external source, as well as by the optical fiber used for the detection of the reflectivity signal. An aperture in the lower cylinder allows for illumination of the sample on the back: in this case the fiber collects the evanescent wave induced at the top of the sample. Another aperture in the lower cylinder allows measurement of the reflected light which includes a contribution due to the interaction with the fiber. Also photocurrent experiments can be easily performed by illuminating the sample with the fiber and detecting the transmitted signal using a current-voltage converter mounted inside the top cylinder. A video-camera that can reach 170 enlargements is mounted on the top cylinder for positioning the fiber on particular regions of the sample. Reflectivity and photocurrent measurements have been performed on uncoated neurons, CsI compound, Au/GaAs, and PtSi/Si systems, reaching a resolution well below the diffraction limit.

  6. Differential phase contrast x-ray microimaging with scanning-imaging x-ray microscope optics.

    PubMed

    Takeuchi, Akihisa; Suzuki, Yoshio; Uesugi, Kentaro

    2012-08-01

    A novel x-ray microimaging system that consists of a scanning microscope optics with a one-dimensional focusing (line-focusing) device and an imaging microscope optics with a one-dimensional objective is developed. These two optical systems are set normal to each other regarding the optical axis. A two-dimensional image is obtained with one-dimensional translation scan of the line probe. During scans, positional data in the normal to the scanning direction are obtained simultaneously with the imaging microscope optics. Differential phase contrast (DPC) image and absorption contrast (AC) image can be arbitrarily obtained by image processing after data acquisition. Preliminary experiment has been carried out by using a couple of one-dimensional Fresnel zone plate as the linear-focusing device and the one-dimensional objective. Two-dimensional DPC and AC images of test sample have been successfully obtained with 8 keV x-rays.

  7. Microscopic description of intraband absorption in graphene: the occurrence of transient negative differential transmission.

    PubMed

    Kadi, Faris; Winzer, Torben; Malic, Ermin; Knorr, Andreas; Göttfert, F; Mittendorff, M; Winnerl, S; Helm, M

    2014-07-18

    We present a microscopic explanation of the controversially discussed transient negative differential transmission observed in degenerate optical pump-probe measurements in graphene. Our approach is based on the density matrix formalism allowing a time- and momentum-resolved study of carrier-light, carrier-carrier, and carrier-phonon interaction on microscopic footing. We show that phonon-assisted optical intraband transitions give rise to transient absorption in the optically excited hot carrier system counteracting pure absorption bleaching of interband transitions. While interband transition bleaching is relevant in the first hundreds of fs after the excitation, intraband absorption sets in at later times. In particular, in the low excitation regime, these intraband absorption processes prevail over the absorption bleaching resulting in a zero crossing of the differential transmission. Our findings are in good qualitative agreement with recent experimental pump-probe studies.

  8. Precise Longitudinal Tracking of Microscopic Structures in Melanocytic Nevi Using Reflectance Confocal Microscopy: A Feasibility Study.

    PubMed

    Scope, Alon; Selinger, Limor; Oliviero, Margaret; Farnetani, Francesca; Moscarella, Elvira; Longo, Caterina; Rabinovitz, Harold S; Pellacani, Giovanni

    2016-03-01

    Reflectance confocal microscopy (RCM), a cellular-level, in vivo imaging technique, may be potentially used for monitoring melanocytic neoplasms for microscopic stability vs changes over time. To test feasibility of using RCM to track specific microscopic structures within nevi over 1 year. This was an observational study, a review of prospectively acquired RCM images, performed at a tertiary academic medical center. Seventeen patients were enrolled from adult patients presenting to pigmented lesion clinic; from each participant, 3 confirmed benign nevi were randomly selected from the upper and lower back and from the lower extremity. Nevi underwent standardized RCM imaging at baseline and after 1 year. We tested interobserver reproducibility in recognition of tissue anchors, RCM structures that can be identified at 2 time points. We used 2 tests to measure concordance between independent readers: (1) In the multiple choice matching test (n = 43 nevi), readers were shown a tissue anchor in a baseline RCM image (≤ 1 × 1-mm field-of-view) and asked to identify the same structure in 1 of 4 equally sized RCM images obtained from the same nevus at follow-up. (2) In the annotation test (n = 29 nevi), readers were shown a tissue anchor in a follow-up RCM image (≤ 1 × 1-mm field-of-view) and asked to annotate the corresponding location of this structure in the baseline RCM mosaic image (≤ 5 × 5-mm field-of-view) from the same nevus; good agreement was defined as annotations deviant by less than 10% of the mosaic's width. In total, 17 patients (mean age, 45 years [range, 28-70 years]; 10 [59%] were women) contributed a total of 51 nevi, of which 44 nevi (86%) were used for the study. Images from 7 nevi (14%) were suboptimal in quality. Tissue anchors were identified at both time points in all 44 nevi. Selected tissue anchors were located at a mean depth of 54.3 µm; the most commonly selected anchors (37 of 44 images [84.1%]) were dermal papillae. In the multiple

  9. A combined light sheet fluorescence and differential interference contrast microscope for live imaging of multicellular specimens.

    PubMed

    Baker, R P; Taormina, M J; Jemielita, M; Parthasarathy, R

    2015-05-01

    We describe a microscope capable of both light sheet fluorescence microscopy and differential interference contrast microscopy (DICM). The two imaging modes, which to the best of our knowledge have not previously been combined, are complementary: light sheet fluorescence microscopy provides three-dimensional imaging of fluorescently labelled components of multicellular systems with high speed, large fields of view, and low phototoxicity, whereas differential interference contrast microscopy reveals the unlabelled neighbourhood of tissues, organs, and other structures with high contrast and inherent optical sectioning. Use of a single Nomarski prism for differential interference contrast microscopy and a shared detection path for both imaging modes enables simple integration of the two techniques in one custom microscope. We provide several examples of the utility of the resulting instrument, focusing especially on the digestive tract of the larval zebrafish, revealing in this complex and heterogeneous environment anatomical features, the behaviour of commensal microbes, immune cell motions, and more. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

  10. Modeling ion channel dynamics through reflected stochastic differential equations

    NASA Astrophysics Data System (ADS)

    Dangerfield, Ciara E.; Kay, David; Burrage, Kevin

    2012-05-01

    Ion channels are membrane proteins that open and close at random and play a vital role in the electrical dynamics of excitable cells. The stochastic nature of the conformational changes these proteins undergo can be significant, however current stochastic modeling methodologies limit the ability to study such systems. Discrete-state Markov chain models are seen as the “gold standard,” but are computationally intensive, restricting investigation of stochastic effects to the single-cell level. Continuous stochastic methods that use stochastic differential equations (SDEs) to model the system are more efficient but can lead to simulations that have no biological meaning. In this paper we show that modeling the behavior of ion channel dynamics by a reflected SDE ensures biologically realistic simulations, and we argue that this model follows from the continuous approximation of the discrete-state Markov chain model. Open channel and action potential statistics from simulations of ion channel dynamics using the reflected SDE are compared with those of a discrete-state Markov chain method. Results show that the reflected SDE simulations are in good agreement with the discrete-state approach. The reflected SDE model therefore provides a computationally efficient method to simulate ion channel dynamics while preserving the distributional properties of the discrete-state Markov chain model and also ensuring biologically realistic solutions. This framework could easily be extended to other biochemical reaction networks.

  11. Fundamental solutions for partial differential equations with reflection group invariance

    NASA Astrophysics Data System (ADS)

    Berest, Yuri; Molchanov, Yuri

    1995-08-01

    The Dunkl differential-difference operator associated with a finite reflection group is used to extend the Weyl-Heisenberg algebra. The subalgebra of mastersymmetries graded by the characters of the Coxeter group W is constructed. It provides us with a new class of intertwining operators for appropriate W-invariant differential equations. These intertwining operators turn out to be suitable for constructing fundamental solutions. The remarkable example is given by the iterated wave operator with a Calogero-type potential for which the fundamental solution can be derived through the relevant intertwining operator in an explicit form. It is found that under appropriate conditions such an equation satisfies Huygens's principle in the sense that its fundamental solution possesses a nontrivial (inner) lacuna.

  12. Differentiation of live-viable versus dead bacterial endospores by calibrated hyperspectral reflectance microscopy.

    PubMed

    Anderson, J; Reynolds, C; Ringelberg, D; Edwards, J; Foley, K

    2008-10-01

    This paper describes the use of hyperspectral imaging microscopy (HIM) for the characterization and differentiation of live viable versus dead/non-viable bacterial endospores for two species of Bacillus. To accomplish this, endospore-forming Bacillus were cultured and differentiated into endospores. Non-viable endospores were produced using sporicidal methods representing standard decontamination procedures incorporating chlorine and peroxide. Finally, endospore samples were lyophilized to prepare them for spectral analysis. Prior to HIM, baseline spectral reflectance characterizing the endospores was measured using an ASD (400-900 nm) reflectance spectrometer. These data were used to calibrate the resulting spectral image data. HIM data comprising 32 images ranging from 400 to 720 nm (visible to near infrared) were recorded using a C-mounted VariSpec hyperspectral camera attached to an epifluorescent microscope. The images produced by the system record the reflectance and absorption features of endospores based on the structure of the outer coat. Analysis of the HIM data was performed using accepted image and spectral processing routines. Where peroxide was the sporicide, changes in the outer endospore coat contributed to structurally significant visible and near infrared signature differences between live-viable versus dead, non-viable endospores. A statistical test for divergence, a method for scoring spectral structural diversity, also showed the difference between viable and non-viable peroxide killed endospores to be statistically significant. These findings may lead to an improved optical procedure to rapidly identify viable and non-viable endospores in situations of decontamination.

  13. A confocal video-rate laser-beam scanning reflected-light microscope with no moving parts.

    PubMed

    Goldstein, S R; Hubin, T; Rosenthal, S; Washburn, C

    1990-01-01

    A no-moving-parts, 30 frames/s, laser-beam scanning confocal reflected-light microscope has been developed. In principle, the technique can be extended to fluorescence and transmission light microscopy. Acousto-optic beam deflectors controlled by digital electronics move a laser beam in a 512-line interlaced 8.5 x 8.5-mm raster. The light passes through a beam splitter, enters an inverted microscope through the side camera port, and is imaged at the object by the microscope objective. Reflected light returns through the objective, exits the camera port, is reflected off the beam splitter, and is imaged on to the photocathode of an image dissector tube (IDT). Confocality is provided by raster scanning the IDT aperture coincident with the congruent image of the laser beam incident on the object. Real-time jitter-free reflected light images of a variety of biological objects have been produced. Computer-controlled alignment of the laser scan and IDT is performed in several seconds.

  14. Modelling biochemical reaction systems by stochastic differential equations with reflection.

    PubMed

    Niu, Yuanling; Burrage, Kevin; Chen, Luonan

    2016-05-07

    In this paper, we gave a new framework for modelling and simulating biochemical reaction systems by stochastic differential equations with reflection not in a heuristic way but in a mathematical way. The model is computationally efficient compared with the discrete-state Markov chain approach, and it ensures that both analytic and numerical solutions remain in a biologically plausible region. Specifically, our model mathematically ensures that species numbers lie in the domain D, which is a physical constraint for biochemical reactions, in contrast to the previous models. The domain D is actually obtained according to the structure of the corresponding chemical Langevin equations, i.e., the boundary is inherent in the biochemical reaction system. A variant of projection method was employed to solve the reflected stochastic differential equation model, and it includes three simple steps, i.e., Euler-Maruyama method was applied to the equations first, and then check whether or not the point lies within the domain D, and if not perform an orthogonal projection. It is found that the projection onto the closure D¯ is the solution to a convex quadratic programming problem. Thus, existing methods for the convex quadratic programming problem can be employed for the orthogonal projection map. Numerical tests on several important problems in biological systems confirmed the efficiency and accuracy of this approach.

  15. Living Matter Observations with a Novel Hyperspectral Supercontinuum Confocal Microscope for VIS to Near-IR Reflectance Spectroscopy

    PubMed Central

    Bertani, Francesca R.; Ferrari, Luisa; Mussi, Valentina; Botti, Elisabetta; Costanzo, Antonio; Selci, Stefano

    2013-01-01

    A broad range hyper-spectroscopic microscope fed by a supercontinuum laser source and equipped with an almost achromatic optical layout is illustrated with detailed explanations of the design, implementation and data. The real novelty of this instrument, a confocal spectroscopic microscope capable of recording high resolution reflectance data in the VIS-IR spectral range from about 500 nm to 2.5 μm wavelengths, is the possibility of acquiring spectral data at every physical point as defined by lateral coordinates, X and Y, as well as at a depth coordinate, Z, as obtained by the confocal optical sectioning advantage. With this apparatus we collect each single scanning point as a whole spectrum by combining two linear spectral detector arrays, one CCD for the visible range, and one InGaAs infrared array, simultaneously available at the sensor output channel of the home made instrument. This microscope has been developed for biomedical analysis of human skin and other similar applications. Results are shown illustrating the technical performances of the instrument and the capability in extracting information about the composition and the structure of different parts or compartments in biological samples as well as in solid statematter. A complete spectroscopic fingerprinting of samples at microscopic level is shown possible by using statistical analysis on raw data or analytical reflectance models based on Abelés matrix transfer methods. PMID:24233077

  16. Living matter observations with a novel hyperspectral supercontinuum confocal microscope for VIS to near-IR reflectance spectroscopy.

    PubMed

    Bertani, Francesca R; Ferrari, Luisa; Mussi, Valentina; Botti, Elisabetta; Costanzo, Antonio; Selci, Stefano

    2013-10-25

    A broad range hyper-spectroscopic microscope fed by a supercontinuum laser source and equipped with an almost achromatic optical layout is illustrated with detailed explanations of the design, implementation and data. The real novelty of this instrument, a confocal spectroscopic microscope capable of recording high resolution reflectance data in the VIS-IR spectral range from about 500 nm to 2.5 μm wavelengths, is the possibility of acquiring spectral data at every physical point as defined by lateral coordinates, X and Y, as well as at a depth coordinate, Z, as obtained by the confocal optical sectioning advantage. With this apparatus we collect each single scanning point as a whole spectrum by combining two linear spectral detector arrays, one CCD for the visible range, and one InGaAs infrared array, simultaneously available at the sensor output channel of the home made instrument. This microscope has been developed for biomedical analysis of human skin and other similar applications. Results are shown illustrating the technical performances of the instrument and the capability in extracting information about the composition and the structure of different parts or compartments in biological samples as well as in solid statematter. A complete spectroscopic fingerprinting of samples at microscopic level is shown possible by using statistical analysis on raw data or analytical reflectance models based on Abelés matrix transfer methods.

  17. Observation of Amorphous Recording Marks Using Reflection-Mode Near-Field Scanning Optical Microscope Supported by Optical Interference Method

    NASA Astrophysics Data System (ADS)

    Sakai, Masaru; Mononobe, Shuji; Yusu, Keiichiro; Tadokoro, Toshiyasu; Saiki, Toshiharu

    2005-09-01

    A signal enhancing technique for a reflection-mode near-field scanning optical microscope (NSOM) is proposed. Optical interference between the signal light, from an aperture at the tip of a tapered optical fiber, and the reflected light, from a metallic coating around the aperture, enhances the signal intensity. We used a rewritable high-definition digital versatile disc (HD DVD) with dual recording layers as a sample medium, and demonstrated observation of amorphous recording marks on the semitransparent (the first) recording layer. In spite of low optical contrast between the crystal region and the amorphous region on this layer, we successfully observed recording marks with good contrast.

  18. Angle of incidence averaging in reflectance measurements with optical microscopes for studying layered two-dimensional materials.

    PubMed

    Saigal, Nihit; Mukherjee, Amlan; Sugunakar, Vasam; Ghosh, Sandip

    2014-07-01

    Reflectance spectrum measured using an optical microscope with a large numerical aperture objective lens is shown to get modified. The change is most prominent when there are optical interference related features in the spectrum. This modification is shown to arise primarily due to the wide range of angles of incidence involved in the measurement and a simple formulation is provided to correct for this in simulations. The importance of such analysis is brought out through a reflectance contrast spectroscopy based study for identifying mono-layer and bi-layer graphene and MoS2.

  19. A Differential Reflective Intensity Optical Fiber Angular Displacement Sensor

    PubMed Central

    Jia, Binghui; He, Lei; Yan, Guodong; Feng, Yong

    2016-01-01

    In this paper, a novel differential reflective intensity optical fiber angular displacement sensor was proposed. This sensor can directly measure the angular and axial linear displacement of a flat surface. The structure of the sensor probe is simple and its basic principle was first analyzed according to the intensity modulation mechanisms. Secondly, in order to trim the dark output voltage to zero, the photoelectric conversion circuit was developed to adjust the signals. Then, the sensor model including the photoelectric conversion circuit has been established, and the influence of design parameters on the sensor output characteristic has been simulated. Finally, the design parameters of the sensor structure were obtained based on the simulation results; and an experimental test system was built for the sensor calibration. Experimental results show that the linear angular range and the sensitivity of the sensor were 74.4 and 0.051 V/°, respectively. Its change rules confirm the operating principle of the sensor well. PMID:27649199

  20. Anisotropic Differential Reflectance Spectroscopy of Thin GeSe

    NASA Astrophysics Data System (ADS)

    Matson, Joseph; Woods, Grace; Churchill, Hugh

    2017-01-01

    Atomically thin monochalcogenides are predicted to exhibit a two-dimensional structural phase transition. This phase transition could be useful for designing new phase change memory devices. The critical temperature is dependent on the material as well as the thickness, and is predicted to occur just above room temperature for monolayer GeSe. We used differential reflectance spectroscopy on thin samples of GeSe to measure changes in the optical anisotropy with temperature as a signature of this phase transition. We constructed an apparatus for temperature-depedendent spectroscopy of micro-scale GeSe samples, and measured anisotropic optical absorption of thin GeSe. We observed a decrease in optical anisotropy of GeSe at elevated temperatures, which may be a first indication of the continuous transition from a rectangular to a square lattice in that material. This work was supported by NSF REU Grant #EEC-1359306.

  1. A Differential Reflective Intensity Optical Fiber Angular Displacement Sensor.

    PubMed

    Jia, Binghui; He, Lei; Yan, Guodong; Feng, Yong

    2016-09-16

    In this paper, a novel differential reflective intensity optical fiber angular displacement sensor was proposed. This sensor can directly measure the angular and axial linear displacement of a flat surface. The structure of the sensor probe is simple and its basic principle was first analyzed according to the intensity modulation mechanisms. Secondly, in order to trim the dark output voltage to zero, the photoelectric conversion circuit was developed to adjust the signals. Then, the sensor model including the photoelectric conversion circuit has been established, and the influence of design parameters on the sensor output characteristic has been simulated. Finally, the design parameters of the sensor structure were obtained based on the simulation results; and an experimental test system was built for the sensor calibration. Experimental results show that the linear angular range and the sensitivity of the sensor were 74.4 and 0.051 V/°, respectively. Its change rules confirm the operating principle of the sensor well.

  2. Interoceptive–reflective regions differentiate alexithymia traits in depersonalization disorder

    PubMed Central

    Lemche, Erwin; Brammer, Michael J.; David, Anthony S.; Surguladze, Simon A.; Phillips, Mary L.; Sierra, Mauricio; Williams, Steven C.R.; Giampietro, Vincent P.

    2013-01-01

    It is unclear to what degree depersonalization disorder (DPD) and alexithymia share abnormal brain mechanisms of emotional dysregulation. We compared cerebral processing of facial expressions of emotion in individuals with DPD to normal controls (NC). We presented happy and sad emotion expressions in increasing intensities from neutral (0%) through mild (50%) to intense (100%) to DPD and non-referred NC subjects in an implicit event-related fMRI design, and correlated respective brain activations with responses on the 20-item Toronto Alexithymia Scale (TAS-20) and its three subscales F1-F3. The TAS-20 predicts clinical diagnosis of DPD with a unique variance proportion of 38%. Differential regression analysis was utilized to ascertain brain regions for each alexithymia subscale. Differential regions of total alexithymia severity for happy emotion were the globus pallidus externus; for identifying feelings (TAS-20 F1 subscale), the right anterior insula; for description of feelings (F2), the right dorsal mid-anterior cingulate gyrus (BA 24); and for externally oriented cognitive style (F3), the left paracingulate gyrus (BA 32). For sad emotion, the differential region for the total TAS-20 score was the dorsal anterior cingulate gyrus (BA 24); for TAS-20 F1, the left inferior anterior insula; for TAS-20 F2, the right PCC (BA 31); and for TAS-20 F3, the right orbital gyrus (BA 10). Supporting our hypotheses, the ascertained brain regions for TAS-20 subscales subserve interoception, monitoring and reflection of internal states and emotion. The presented analyses provide evidence that alexithymia plays a substantial role in emotional dysregulation in DPD, presumably based on restrictions in interoception. PMID:23932225

  3. Investigation of select energetic materials by differential reflection spectrometry

    NASA Astrophysics Data System (ADS)

    Fuller, Anna Marie

    The presence of explosive or energetic materials is prevalent in today's world. Terrorists continue to target buildings and mass transit systems with explosive devices. The detection of these energetic materials is necessary to insure national security and welfare. Detection techniques such as X-ray scanners, Raman spectroscopy, Terahertz spectroscopy and ion mobility spectrometry are in current use or development; however, none of these are appropriate for all necessary applications. These techniques include. The present document provides an overview of the current detection techniques and describes a new technique for detecting energetic materials called differential reflection spectrometry (DRS). DRS essentially measures the optical absorption of energetic materials. The use of DRS has led to the discovery of previously unreported optical characteristics for some energetic compounds that are unique to the individual material. These optical characteristics consist of absorption shoulders between 270 and 420 nm, e.g. near 420 nm for 2, 4, 6 trinitrotoluene (TNT). In the presented research, the origin of the differential reflection spectra obtained was investigated using several techniques including UV-Visible spectrophotometry (transmission and reflection) and computer molecular modeling. Experimental DRS spectra of TNT, hexahydro-1,3,5 trinitro-1,3,5 triazine (RDX), octahydro 1,3,5,7-tetranitro-1,3,5,6 tetrazocine (HMX), 18 pentaerythritol tetranitrate (PETN), and 2, 4, 6, n-tetranitro-n-methylaniline (Tetryl) were taken and analyzed. From the experimental results and verification by molecular modeling, it was found that the absorption features observed in the redder region of the UV range (270--420 nm) are due to molecular orbital transitions in the nitro (NO2) groups of the measured explosives. These transitions only occur in specific conditions, such as high concentration solutions and solids, where the normally forbidden transitions are allowed. The unique

  4. A simple method for overcoming some problems when observing thick reflective biological samples with a confocal scanning laser microscope.

    PubMed

    Rumio, C; Morini, M; Miani, A; Barajon, I; Castano, P

    1995-01-01

    A simple device is described, which allows the range of depth of scanning to be reduced when observing thick reflecting biological samples with a confocal scanning laser microscope (CSLM). Thick histological sections of human skin and rat brain stem were mounted between two coverslips ('sandwich' style) and the optical tomography was performed from both sides by turning the 'sandwich' upside-down. The samples were impregnated using standard Golgi-Cox, 'rapid Golgi' or other silver methods. The ability to turn the 'sandwich' upside-down is particularly useful when the reflective structure inspected is deep inside the section, i.e., near the lower surface of the specimen, or when it is opaque to the laser beam or excessively reflective.

  5. Real-time, non-invasive microscopic confirmation of clinical diagnosis of bullous pemphigoid using in vivo reflectance confocal microscopy.

    PubMed

    Ardigò, M; Agozzino, M; Amorosi, B; Moscarella, E; Cota, C; de Abreu, L; Berardesca, E

    2014-05-01

    Bullous pemphigoid is an autoimmune disease affecting prevalently the elder. In vivo reflectance confocal microscopy is a non-invasive technique for real-time imaging of the skin with cellular-level resolution. No previous data has been reported about confocal microscopy of bullous pemphigoid. Aim of this preliminary study is the evaluation of the potential of in vivo reflectance confocal microscopy for real-time, microscopical confirmation of clinical bullous pemphigoid diagnosis. A total of nine lesions from patients affected by pemphigoid underwent in vivo reflectance confocal microscopy before histological examination. In our preliminary study, confocal microscopy showed high grade of correspondence to histopathology. In particular, presence of sub-epidermal cleft and variable amount of oedema of the upper dermis associated with inflammatory cells infiltration were seen as prevalent confocal features in the bullous lesions considered. Differently, in urticarial lesions, no specific features could be appreciated at confocal analysis beside the presence of signs of spongiosis and perivascular inflammation. Confocal microscopy seems to be useful for in vivo, microscopical confirmation of the clinical suspect of bullous pemphigoid and for biopsy site selection in urticarial lesions to obtain a more significant specimen for histopathological examination. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

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

    NASA Astrophysics Data System (ADS)

    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.

  7. [Differential Reflectance Spectroscopy for In-Situ Monitoring of Organic Thin Films Growth in Vacuum Environment].

    PubMed

    Yao, Yao; Hu, Chun-guang; Xu, Zhen-yuan; Zhang, Lei; Fu, Xing; Hu, Xiao-tang

    2015-05-01

    For realizing the real-time monitoring of organic thin film preparation process in vacuum environment, the present paper proposes a high precision measurement approach based on differential reflectance spectroscopy (DRS). An optical system was constructed with off the shelf optical components, such as off-axis parabolic mirror, optical flat and optical fiber. A differential algorithm was employed to analyze the spectral signals. Based on the homebuilt setup, instability induced by variation of temperature was investigated. It was concluded that with the good control of temperature and air flow, the measurement repeatability of this system is better than 2 per thousand for a long-term period. Furthermore, an initial stage of organic thin film growth of pentacene molecules on the surface of Au was studied. As compared with the data of film thickness gauge and atomic force microscope, DR spectra accurately recorded the fine optical evolution with sub-monolayer resolution, which is related to the growth of the thin film. As a result, the DR optical system exhibits characteristics of broad spectrum (range from 300 to 820 nm), high stability (repeatability better than 2X 10(-3)), and high precision (sub-monolayer resolution) after efforts were done to decrease the influences on the spectral quality produced by misalignments of the optical components, the defects of the optics, and the disturbances of the environmental conditions. It is indicated that the proposed DR method is suitable for real-time online monitoring of thin film growth with high precision.

  8. Label-free detection of biomolecular interactions in microarray format using oblique-incidence reflectivity difference microscopes

    NASA Astrophysics Data System (ADS)

    Sun, Yung-Shin

    Microarrays of biological molecules are useful tools for discovery and functionality characterization in fundamental and applied research of genomics, proteomics, glycomics and cytomics. They provide a high-throughput platform that enables parallel studies of hundreds to tens of thousands of distinct biomolecular reactions. Characterization of binding reactions between surface-immobilized targets and solutions-phase analytes routinely involves fluorescence-based detection methods. However, labeling analytes inevitably changes innate properties of the molecules and in turn modifies analyte-target interactions in an often uncharacterized way. As a result, label-free microarray detection is desirable. In this dissertation, optical microscopes based on oblique-incidence reflectivity difference (OI-RD) technique are developed and used to detect biomolecular interactions in microarray format. OI-RD, a most sensitive form of optical elliposometry, measures the difference in reflectivity change (both magnitude and phase) between p- and s-polarized components of an optical beam. Such a difference is related to the thickness and dielectric constant of surface-immobilized biomolecules. Specially, I use these OI-RD microscopes to study different biomolecular interactions including (1) Effect of fluorescently labeling protein probes on kinetics of protein-ligand interactions; (2) Macromolecular scaffolds for immobilizing small molecule microarrays for detection of protein-ligand interactions; (3) Lectin-glyan and virus-glycan interactions; (4) Others applications such as protein-protein, DNA-DNA, DNA-protein, sugar-protein, and small molecule-protein interactions. These experimental results demonstrate that the OI-RD microscopes will serve as powerful tools in biosensing, high-throughput screening, and other applications in biophysics, biochemistry and biomedical engineering.

  9. An efficient algorithm for detecting spherical particles from differential interference microscopic images

    NASA Astrophysics Data System (ADS)

    Hong, Hyeyoung; Nam, Jaewook

    2017-08-01

    Particulate films have become critical parts in electronics industries because they can provide the required optical and electrical properties. Microstructures, which consist of various particles inside the films, strongly influence the performance of devices. Therefore, the visualization and detection of particles can be an indirect method of determining the device performance without destroying samples. In this study, we propose an image analysis algorithm to detect spherical particles inside a thin film visualized by a differential interference contrast microscope. Our goal is to develop a robust and efficient algorithm specifically for uniform-sized spherical particles sandwiched between two solid thin and flat plates, which are usually applied in anisotropic conductive films that provide electrical and mechanical connections between two electrodes from a chip and substrate. Our algorithm uses correlation and masking to detect particle centers and algebraic operations to reconstruct particle shapes. Despite the simple processes involved, our algorithm has yielded accurate results in particle detection compared with manual detections and synthetically generated ground-truth images.

  10. Minimum surface-effect microgripper design for force-reflective telemanipulation of a microscopic environment

    NASA Technical Reports Server (NTRS)

    Goldfarb, Michael; Celanovic, Nikola

    1996-01-01

    This paper describes the fundamental physical motivations for a minimum surface effect design, and presents a microgripper that incorporates a piezoelectric ceramic actuator and a flexure-based structure and transmission. The microgripper serves effectively as a one degree-of-freedom prototype of a minimum surface effect micromanipulator design. Data is presented that characterizes the microgripper performance under both pure position and pure force control, followed by a discussion of the attributes and limitations of flexure-based design. The microgripper is interfaced with a force reflective macrogripper, and the pair is controlled with a hybrid position/force scheme. Data is presented that illustrates the effective operation of the telerobotic pair.

  11. Minimum Surface-Effect Microgripper Design for Force-Reflective Telemanipulation of a Microscopic Environment

    NASA Technical Reports Server (NTRS)

    Goldfarb, Michael; Celanovic, Nikola

    1996-01-01

    This paper describes the fundamental physical motivations for minimum surface effect design, and presents a microgripper that incorporates a piezoelectric ceramic actuator and a flexure-based structure and transmission. The microgripper serves effectively as a one degree-of-freedom prototype of minimum surface effect micromanipulator design. Data is presented that characterizes the microgripper performance under both pure position and pure force control, followed by a discussion of the attributes and limitations of flexure-based design. The microgripper is interfaced with a force-reflective macrogripper, and the pair controlled with a hybrid position/force scheme. Data is presented that illustrates the effective operation of the telerobotic pair.

  12. Microscopic observation of strain induced in heteroepitaxial layers with reflection type of infrared polariscope

    NASA Astrophysics Data System (ADS)

    Yamada, Masayoshi; Chu, Tao

    2000-03-01

    Photoelastic measurements using a reflection type of infrared polariscope have been done for the first time to investigate birefringence or residual strain induced in as-grown and pulsed-laser-annealed silicon-on-sapphire (SOS) wafers. It was found that the residual strain, arising from mismatchings of the lattice constants and the thermal expansion coefficients between silicon and sapphire, was reduced effectively by pulsed-laser annealing with laser energy density beyond a threshold value. Also found was a mosaic pattern due to local melting at about the threshold energy density, indicating the coexistence of solid and liquid phases.

  13. Commentary: taking a deep breath before reflecting on differential response.

    PubMed

    Merkel-Holguin, Lisa; Bross, Donald C

    2015-01-01

    Although there are certainly limitations to each and every research and evaluation project in child welfare, as with other fields of study, understanding DR as a CPS reform has been fostered through many thoughtful and rigorous studies that have employed random control trial evaluation designs. For each assumption addressed in this commentary, we have raised a few questions. For all interested in CPS reform, other questions arise because child protection and child welfare professionals are trying to encourage more scientific ways of thinking as a means of engendering improvements: 1. Has the research on DR spotlighted the inadequacy of CPS interventions, either AR or IR? A high percentage of CPS responses are short-term. Is it reasonable to expect significant differences between AR and IR families and improvements in the CPS population, given that families often present with problems characterized as intractable but the intensity of the CPS response, coupled with limited service availability and accessibility, may not be sufficient to meet family needs? 2. Has the DR research, which has mainly focused on AR families, also highlighted the glaring absence of quality research in what is effective in producing positive outcomes for families that receive traditional child abuse and neglect investigations? 3. Does the implementation of DR move the CPS field ahead in terms of making better triage decisions, identifying especially those that require CPS involvement as compared to those who will benefit from but might not absolutely need intervention? Is 'triage' an explicit assumption of the DR innovation? Is it an implicit assumption of DR, however defined? If triage is not part of the research, does the ability of child protection to respond both differentially and also correctly to cases needing most, some, or no attention remain unknown? Until there is a reliable and valid way for determining for which families services are most urgently needed, are many reforms in CPS

  14. Differential phase shift of partially reflected radio waves.

    NASA Technical Reports Server (NTRS)

    Connolly, D. J.

    1971-01-01

    The addition of phase difference measurements to differential absorption experiments is shown to be both feasible and desirable. The phase information can provide a more sensitive measurement of electron density above about 75 km. The differential phase shift is only weakly dependent on collision frequency in this range, and so an accurate collision frequency profile is not a prerequisite. The differential phase shift and differential absorption measurements taken together can provide both electron density and collision frequency data from about 70 to 90 km.

  15. Differential phase shift of partially reflected radio waves.

    NASA Technical Reports Server (NTRS)

    Connolly, D. J.

    1971-01-01

    The addition of phase difference measurements to differential absorption experiments is shown to be both feasible and desirable. The phase information can provide a more sensitive measurement of electron density above about 75 km. The differential phase shift is only weakly dependent on collision frequency in this range, and so an accurate collision frequency profile is not a prerequisite. The differential phase shift and differential absorption measurements taken together can provide both electron density and collision frequency data from about 70 to 90 km.

  16. Effects of microscopic iron metal on the reflectance spectra of glass and minerals

    NASA Technical Reports Server (NTRS)

    Allen, C. C.; Morris, R. V.; Lauer, H. V., Jr.; Mckay, D. S.

    1993-01-01

    Maturity, which is a measure of the time lunar soils have been in the upper approximately 1 mm of the surface, is correlated with changes in the soils' optical properties. Mature soil is darker and somewhat redder than immature soil of the same composition, and features in the reflectance spectrum become more subdued with increasing maturity. The maturation process also involves accumulation of agglutinitic glass and submicroscopic metallic iron particles. We have produced submicrometer iron metal blebs on the surface and within glass and mineral grains by the method of high-temperature reduction. This technique has permitted the determination of optical changes in samples much simpler than lunar soil, and offers a useful tool with which to investigate the maturation process.

  17. Differential expression of interleukin-1/Toll-like receptor signaling regulators in microscopic and ulcerative colitis.

    PubMed

    Günaltay, Sezin; Nyhlin, Nils; Kumawat, Ashok Kumar; Tysk, Curt; Bohr, Johan; Hultgren, Olof; Hultgren Hörnquist, Elisabeth

    2014-09-14

    To investigate Toll-like receptor (TLR) signaling regulators in microscopic and ulcerative colitis patients. Total RNA and microRNA were isolated from fresh frozen colonic biopsies of non-inflamed controls and patients with active or in-remission collagenous colitis (CC), lymphocytic colitis (LC), or ulcerative colitis (UC). We compared expressions of interleukin-1 receptor-associated kinase (IRAK)-2, IRAK-M, interleukin (IL)-37, microRNA (miR)-146a, miR-155, and miR-21 using quantitative real time reverse transcription polymerase chain reaction. IRAK-M expression was increased in LC patients with active disease in histopathological remission (LC-HR; P = 0.02) and UC patients (P = 0.01), but no differences in IRAK-2 expression were detected compared to controls. miR-146a, -155 and -21 expressions were increased in LC-HR (P = 0.04, 0.07, and 0.004) and UC (P = 0.02, 0.04 and 0.03) patients. miR-146a and miR-21 expressions were significantly enhanced in UC patients compared to UC remission (UC-R; P = 0.01 and 0.04). Likewise, active CC patients showed significantly increased expression of miR-155 (P = 0.003) and miR-21 (P = 0.006). IL-37 expression was decreased in both CC (P = 0.03) and LC (P = 0.04) patients with a similar trend in UC patients but not statistically significant, whilst it was increased in UC-R patients compared to controls (P = 0.02) and active UC (P = 0.001). The identification of differentially expressed miRNAs, IL-37, and IRAK-M suggests different pathophysiologic mechanisms in various disease stages in LC, CC, and UC.

  18. Differential expression of interleukin-1/Toll-like receptor signaling regulators in microscopic and ulcerative colitis

    PubMed Central

    Günaltay, Sezin; Nyhlin, Nils; Kumawat, Ashok Kumar; Tysk, Curt; Bohr, Johan; Hultgren, Olof; Hultgren Hörnquist, Elisabeth

    2014-01-01

    AIM: To investigate Toll-like receptor (TLR) signaling regulators in microscopic and ulcerative colitis patients. METHODS: Total RNA and microRNA were isolated from fresh frozen colonic biopsies of non-inflamed controls and patients with active or in-remission collagenous colitis (CC), lymphocytic colitis (LC), or ulcerative colitis (UC). We compared expressions of interleukin-1 receptor-associated kinase (IRAK)-2, IRAK-M, interleukin (IL)-37, microRNA (miR)-146a, miR-155, and miR-21 using quantitative real time reverse transcription polymerase chain reaction. RESULTS: IRAK-M expression was increased in LC patients with active disease in histopathological remission (LC-HR; P = 0.02) and UC patients (P = 0.01), but no differences in IRAK-2 expression were detected compared to controls. miR-146a, -155 and -21 expressions were increased in LC-HR (P = 0.04, 0.07, and 0.004) and UC (P = 0.02, 0.04 and 0.03) patients. miR-146a and miR-21 expressions were significantly enhanced in UC patients compared to UC remission (UC-R; P = 0.01 and 0.04). Likewise, active CC patients showed significantly increased expression of miR-155 (P = 0.003) and miR-21 (P = 0.006). IL-37 expression was decreased in both CC (P = 0.03) and LC (P = 0.04) patients with a similar trend in UC patients but not statistically significant, whilst it was increased in UC-R patients compared to controls (P = 0.02) and active UC (P = 0.001). CONCLUSION: The identification of differentially expressed miRNAs, IL-37, and IRAK-M suggests different pathophysiologic mechanisms in various disease stages in LC, CC, and UC. PMID:25232259

  19. All-plastic, miniature, digital fluorescence microscope for three part white blood cell differential measurements at the point of care

    PubMed Central

    Forcucci, Alessandra; Pawlowski, Michal E.; Majors, Catherine; Richards-Kortum, Rebecca; Tkaczyk, Tomasz S.

    2015-01-01

    Three-part differential white blood cell counts are used for disease diagnosis and monitoring at the point-of-care. A low-cost, miniature achromatic microscope was fabricated for identification of lymphocytes, monocytes, and granulocytes in samples of whole blood stained with acridine orange. The microscope was manufactured using rapid prototyping techniques of diamond turning and 3D printing and is intended for use at the point-of-care in low-resource settings. The custom-designed microscope requires no manual adjustment between samples and was successfully able to classify three white blood cell types (lymphocytes, granulocytes, and monocytes) using samples of peripheral whole blood stained with acridine orange. PMID:26601006

  20. Toward the development of a soft x-ray reflection imaging microscope in the Schwarzschild configuration using a soft x-ray laser at 18. 2 nm

    SciTech Connect

    Dicicco, D.; Rosser, R. ); Kim, D.; Suckewer, S. . Plasma Physics Lab.)

    1991-12-01

    We present the recent results obtained from a soft X-ray reflection imaging microscope in the Schwarzschild configuration. The microscope demonstrated a spatial resolution of 0.7 {mu}m with a magnification of 16 at 18.2 nm. The soft X-ray laser at 18.2 nm was used as an X-ray source. Mo/Si multilayers were coated on the Schwarzschild optics and the normal incidence reflectivity at 18.2 nm per surface was measured to be {approximately} 20 %. 18 refs., 6 figs.

  1. Microscopic emission and reflectance thermal infrared spectroscopy: instrumentation for quantitative in situ mineralogy of complex planetary surfaces.

    PubMed

    Edwards, C S; Christensen, P R

    2013-04-10

    The diversity of investigations of planetary surfaces, especially Mars, using in situ instrumentation over the last decade is unprecedented in the exploration history of our solar system. The style of instrumentation that landed spacecraft can support is dependent on several parameters, including mass, power consumption, instrument complexity, cost, and desired measurement type (e.g., chemistry, mineralogy, petrology, morphology, etc.), all of which must be evaluated when deciding an appropriate spacecraft payload. We present a laboratory technique for a microscopic emission and reflectance spectrometer for the analysis of martian analog materials as a strong candidate for the next generation of in situ instruments designed to definitively assess sample mineralogy and petrology while preserving geologic context. We discuss the instrument capabilities, signal and noise, and overall system performance. We evaluate the ability of this instrument to quantitatively determine sample mineralogy, including bulk mineral abundances. This capability is greatly enhanced. Whereas the number of mineral components observed from existing emission spectrometers is high (often >5 to 10 depending on the number of accessory and alteration phases present), the number of mineral components at any microscopic measurement spot is low (typically <2 to 3). Since this style of instrument is based on a long heritage of thermal infrared emission spectrometers sent to orbit (the thermal emission spectrometer), sent to planetary surfaces [the mini-thermal emission spectrometers (mini-TES)], and evaluated in laboratory environments (e.g., the Arizona State University emission spectrometer laboratory), direct comparisons to existing data are uniquely possible with this style of instrument. The ability to obtain bulk mineralogy and atmospheric data, much in the same manner as the mini-TESs, is of significant additional value and maintains the long history of atmospheric monitoring for Mars

  2. Differentiating characteristic microstructural features of cancerous tissues using Mueller matrix microscope.

    PubMed

    Wang, Ye; He, Honghui; Chang, Jintao; Zeng, Nan; Liu, Shaoxiong; Li, Migao; Ma, Hui

    2015-12-01

    Polarized light imaging can provide rich microstructural information of samples, and has been applied to the detections of various abnormal tissues. In this paper, we report a polarized light microscope based on Mueller matrix imaging by adding the polarization state generator and analyzer (PSG and PSA) to a commercial transmission optical microscope. The maximum errors for the absolute values of Mueller matrix elements are reduced to 0.01 after calibration. This Mueller matrix microscope has been used to examine human cervical and liver cancerous tissues with fibrosis. Images of the transformed Mueller matrix parameters provide quantitative assessment on the characteristic features of the pathological tissues. Contrast mechanism of the experimental results are backed up by Monte Carlo simulations based on the sphere-cylinder birefringence model, which reveal the relationship between the pathological features in the cancerous tissues at the cellular level and the polarization parameters. Both the experimental and simulated data indicate that the microscopic transformed Mueller matrix parameters can distinguish the breaking down of birefringent normal tissues for cervical cancer, or the formation of birefringent surrounding structures accompanying the inflammatory reaction for liver cancer. With its simple structure, fast measurement and high precision, polarized light microscope based on Mueller matrix shows a good diagnosis application prospect.

  3. Detection of explosive materials by differential reflection spectroscopy

    NASA Astrophysics Data System (ADS)

    Hummel, Rolf E.; Fuller, Anna M.; Schöllhorn, Claus; Holloway, Paul H.

    2006-06-01

    It is shown that traces of 2,4,6-trinitrotoluene (TNT) display strong and distinct structures in differential reflectograms, near 420 and 250nm. These characteristic peaks are not observed from moth balls, nail polish, polyvinyl chloride, starch, soap, paper, epoxy, aspirin, polycarbonate, aspartame, polystyrene, polyester, fertilizer, or sugar, to mention a few substances which may be in or on a suitcase. The described technique for detection of TNT is fast, inexpensive, reliable, and portable and does not require contact with the surveyed substance. Moreover, we have developed a curve recognition program for field applications of the technique. The origin of the spectra is discussed.

  4. In vivo detection of basal cell carcinoma: comparison of a reflectance confocal microscope and a multiphoton tomograph.

    PubMed

    Ulrich, Martina; Klemp, Marisa; Darvin, Maxim E; König, Karsten; Lademann, Jürgen; Meinke, Martina C

    2013-06-01

    The standard diagnostic procedure for basal cell carcinoma (BCC) is invasive tissue biopsy with time-consuming histological examination. To reduce the number of biopsies, noninvasive optical methods have been developed providing high-resolution skin examination. We present direct comparison of a reflectance confocal microscope (RLSM) and a multiphoton tomograph (MPT) for BCC diagnosis. Both systems are applied to nine patients prior to surgery, and the results are analyzed, including histological results. Both systems prove suitable for detecting typical characteristics of BCC in various stages. The RLSM allows large horizontal overview images to be obtained, enabling the investigator to find the regions of interest quickly, e.g., BCC nests. Elongated cells and palisading structures are easily recognized using both methods. Due to the higher resolution, changes in nucleus diameter or cytoplasm could be visualized with the MPT. Therefore, the nucleus diameter, nucleus/cytoplasm ratio, and cell density are estimated for normal and BCC cells using the MPT. The nucleus of elongated BCC cells is significantly longer than other measured normal skin cells, whereas the cell density and nucleus/cytoplasm ratio of BCC cannot be significantly distinguished from granular cells.

  5. In vivo detection of basal cell carcinoma: comparison of a reflectance confocal microscope and a multiphoton tomograph

    NASA Astrophysics Data System (ADS)

    Ulrich, Martina; Klemp, Marisa; Darvin, Maxim E.; König, Karsten; Lademann, Jürgen; Meinke, Martina C.

    2013-06-01

    The standard diagnostic procedure for basal cell carcinoma (BCC) is invasive tissue biopsy with time-consuming histological examination. To reduce the number of biopsies, noninvasive optical methods have been developed providing high-resolution skin examination. We present direct comparison of a reflectance confocal microscope (RLSM) and a multiphoton tomograph (MPT) for BCC diagnosis. Both systems are applied to nine patients prior to surgery, and the results are analyzed, including histological results. Both systems prove suitable for detecting typical characteristics of BCC in various stages. The RLSM allows large horizontal overview images to be obtained, enabling the investigator to find the regions of interest quickly, e.g., BCC nests. Elongated cells and palisading structures are easily recognized using both methods. Due to the higher resolution, changes in nucleus diameter or cytoplasm could be visualized with the MPT. Therefore, the nucleus diameter, nucleus/cytoplasm ratio, and cell density are estimated for normal and BCC cells using the MPT. The nucleus of elongated BCC cells is significantly longer than other measured normal skin cells, whereas the cell density and nucleus/cytoplasm ratio of BCC cannot be significantly distinguished from granular cells.

  6. Optimization of a high shear wet granulation process using focused beam reflectance measurement and particle vision microscope technologies.

    PubMed

    Arp, Zane; Smith, Ben; Dycus, Eric; O'grady, Des

    2011-08-01

    Application of process analytical technology in the pharmaceutical industry has led to a great number of studies into inline instrumentation. Near-infrared moisture monitoring in fluid bed drying and content uniformity assurance in blending are gaining acceptance for monitoring and quality control of these processes. Although these techniques are a great improvement over traditional methods, each is performed at points in processing wherein processing is well understood and interfacing equipment is relatively easy. More complex unit operations have largely been unexplored due to complexities interfacing inline analytical equipment to unit operations or a lack of methodologies that can be applied to measure attributes of interest. This paper reports results from a study utilizing a focused beam reflectance measurement system equipped with window scraper technology for the inline measurement and control of a high shear wet granulation (HSWG) process. In addition to this, offline results obtained with a particle vision microscope system are compared to verify the results obtained inline. It is shown that using these technologies in monitoring the HSWG process greatly increases process understanding of physical changes occurring during processing through real-time observation of particle size, leading to real-time control of the process.

  7. Algorithms for differentiating between images of heterogeneous tissue across fluorescence microscopes

    PubMed Central

    Chitalia, Rhea; Mueller, Jenna; Fu, Henry L.; Whitley, Melodi Javid; Kirsch, David G.; Brown, J. Quincy; Willett, Rebecca; Ramanujam, Nimmi

    2016-01-01

    Fluorescence microscopy can be used to acquire real-time images of tissue morphology and with appropriate algorithms can rapidly quantify features associated with disease. The objective of this study was to assess the ability of various segmentation algorithms to isolate fluorescent positive features (FPFs) in heterogeneous images and identify an approach that can be used across multiple fluorescence microscopes with minimal tuning between systems. Specifically, we show a variety of image segmentation algorithms applied to images of stained tumor and muscle tissue acquired with 3 different fluorescence microscopes. Results indicate that a technique called maximally stable extremal regions followed by thresholding (MSER + Binary) yielded the greatest contrast in FPF density between tumor and muscle images across multiple microscopy systems. PMID:27699108

  8. Algorithms for differentiating between images of heterogeneous tissue across fluorescence microscopes.

    PubMed

    Chitalia, Rhea; Mueller, Jenna; Fu, Henry L; Whitley, Melodi Javid; Kirsch, David G; Brown, J Quincy; Willett, Rebecca; Ramanujam, Nimmi

    2016-09-01

    Fluorescence microscopy can be used to acquire real-time images of tissue morphology and with appropriate algorithms can rapidly quantify features associated with disease. The objective of this study was to assess the ability of various segmentation algorithms to isolate fluorescent positive features (FPFs) in heterogeneous images and identify an approach that can be used across multiple fluorescence microscopes with minimal tuning between systems. Specifically, we show a variety of image segmentation algorithms applied to images of stained tumor and muscle tissue acquired with 3 different fluorescence microscopes. Results indicate that a technique called maximally stable extremal regions followed by thresholding (MSER + Binary) yielded the greatest contrast in FPF density between tumor and muscle images across multiple microscopy systems.

  9. Differential dynamic microscopy: probing wave vector dependent dynamics with a microscope.

    PubMed

    Cerbino, Roberto; Trappe, Veronique

    2008-05-09

    We demonstrate the use of an ordinary white-light microscope for the study of the q-dependent dynamics of colloidal dispersions. Time series of digital video images are acquired in bright field with a fast camera, and image differences are Fourier analyzed as a function of the time delay between them. This allows for the characterization of the particle dynamics independent of whether or not they can be resolved individually. The characteristic times are measured in a wide range of wave vectors and the results are found to be in good agreement with the theoretically expected values for Brownian motion in a viscous medium.

  10. Re-evaluation of differential phase contrast (DPC) in a scanning laser microscope using a split detector as an alternative to differential interference contrast (DIC) optics.

    PubMed

    Amos, W B; Reichelt, S; Cattermole, D M; Laufer, J

    2003-05-01

    In this paper, differential phase imaging (DPC) with transmitted light is implemented by adding a suitable detection system to a standard commercially available scanning confocal microscope. DPC, a long-established method in scanning optical microscopy, depends on detecting the intensity difference between opposite halves or quadrants of a split photodiode detector placed in an aperture plane. Here, DPC is compared with scanned differential interference contrast (DIC) using a variety of biological specimens and objective lenses of high numerical aperture. While DPC and DIC images are generally similar, DPC seems to have a greater depth of field. DPC has several advantages over DIC. These include low cost (no polarizing or strain-free optics are required), absence of a double scanning spot, electronically variable direction of shading and the ability to image specimens in plastic dishes where birefringence prevents the use of DIC. DPC is also here found to need 20 times less laser power at the specimen than DIC.

  11. Light diffuse reflectance for detection and differentiation of teeth caries lesions

    NASA Astrophysics Data System (ADS)

    Borisova, E.; Uzunov, Tz.; Valkanov, S.; Avramov, L.

    2007-05-01

    One of the goals of the contemporary dentistry is differentiation between carious stages that must be fast, non-invasive procedure, which will allow to the dentists to make reliable judgments. One suitable candidate for such method is reflectance spectroscopy. The objectives of current study are to determine the feasibility of applying the light reflectance spectroscopy technique for detection of different carious stages; therefore reflectance spectra of teeth illuminated at 450- 900 nm light were recorded. There are obtained reflectance signals from the healthy enamel, dentine and different lesion stages of the investigated teeth. These spectra are compared to that, obtained by non-carious tooth lesions - fluorosa and odontolithiasis, resembling on initial carious stages. There is observed a significant decrease of the intensity of the reflected light in blue region in the case of caries. Reflectance signals, obtained from non-carious lesions also have significantly different character and could be used for differentiation between them and initial carious stages. An algorithm for differentiation between carious stages is proposed with diagnostic accuracy achieved up to 86,1% between precarious stage and sound tooth and 100% for determination of deep cavitation. Some comments about role of teeth enamel structure and anisotropy factor of dental layers on the results obtained are also made.

  12. Microscopic Mapping of Subnanometric Motion with Multiple-Beam Differential Holographic Technique

    NASA Astrophysics Data System (ADS)

    Lin, Hungyi

    The measurement of ultrasmall displacement is usually performed by laser interferometry. In most cases, this method is specified for the surface measurement and requires a relatively smooth surface capable of reflecting light. In this research, a newly developed method, mutiple -beam microdifferential holography, is introduced to measure a small configuration change. This configuration change can happen on the surface of an object or inside a semitransparent object. In the experiment, two reference beams are used to record a pair of phase biased holographic images simultaneously. During the image reconstruction, the CCD image acquisition system is employed to record the pair of images one at a time and then process them digitally. The subtraction image intuitively shows that the deformation of tested object occurs between the double exposures applied during the holographic recording. A second object beam, usually a plane wave, is added to the imaging system for the purpose of image registration, which is required for the image processing. Several developments upgraded the system performance. The calibration was done with an extremely consistent moving object, a small air bubble drifting in a glycerine-filled capillary. Displacements as small as 0.4 nanometer are reported. In application, a living cell, a single frog muscle fiber, was under examination. This part of the research focused mainly on the crossbridge mechanism of striated muscle contraction. The images made at the plateau of tetanus suggest either that the cycling time constant is much longer than 10 msec, that the displacement for a power stroke is substantially less than 12 nanometer, or that the crossbridge is not cycling during the isometric force generation. The images made at the initial state of force development suggest that a large number of crossbridges shift toward the actin filament at the onset of the force development and stay there (at least without large scale rotation) even when the

  13. The operational weather radar of Fossalon di Grado (Gorizia, Italy): accuracy of reflectivity and differential reflectivity measurements

    NASA Astrophysics Data System (ADS)

    Bechini, R.; Gorgucci, E.; Scarchilli, G.; Dietrich, S.

    The error structure of radar measurements should be accurately known in order to provide reliable estimates for a number of quantitative meteorological applications, from rainfall rate estimation to cloud microphysics. The aim of this paper is to give a detailed characterization of ZH and ZDR measurements obtained by the weather radar of Fossalon di Grado (Gorizia, Italy). Vertical-looking observations are used to determine the system bias on differential reflectivity and to estimate the measurement error on both ZH and ZDR in the rain medium. It is estimated that no bias is affecting ZDR and the accuracy of ZH and ZDR is 0.8 and 0.1dB, respectively. A similar evaluation is done in the rain medium at larger ranges with the antenna pointing at low elevation angles. The long time stability of the absolute reflectivity calibration is also established by radar-rain gage inter-comparison over almost 200 hours of precipitation data collected during nearly two years.

  14. Reflecting microscope system with a 0.99 numerical aperture designed for three-dimensional fluorescence imaging of individual molecules at cryogenic temperatures.

    PubMed

    Inagawa, H; Toratani, Y; Motohashi, K; Nakamura, I; Matsushita, M; Fujiyoshi, S

    2015-08-04

    We have developed a cryogenic fluorescence microscope system, the core of which is a reflecting objective that consists of spherical and aspherical mirrors. The use of an aspherical mirror allows the reflecting objective to have a numerical aperture (NA) of up to 0.99, which is close to the maximum possible NA of 1.03 in superfluid helium. The performance of the system at a temperature of 1.7 K was tested by recording a three-dimensional fluorescence image of individual quantum dots using excitation wavelengths (λex) of 532 nm and 635 nm. At 1.7 K, the microscope worked with achromatic and nearly diffraction-limited performance. The 1/e(2) radius (Γ) of the point spread function of the reflecting objective in the lateral (xy) direction was 0.212 ± 0.008 μm at λex = 532 nm and was less than 1.2 times the simulated value for a perfectly polished objective. The radius Γ in the axial (z) direction was 0.91 ± 0.04 μm at λex = 532 nm and was less than 1.4 times the simulated value of Γ. The chromatic aberrations between the two wavelengths were one order of magnitude smaller than Γ in each direction.

  15. Reflecting microscope system with a 0.99 numerical aperture designed for three-dimensional fluorescence imaging of individual molecules at cryogenic temperatures

    PubMed Central

    Inagawa, H.; Toratani, Y.; Motohashi, K.; Nakamura, I.; Matsushita, M.; Fujiyoshi, S.

    2015-01-01

    We have developed a cryogenic fluorescence microscope system, the core of which is a reflecting objective that consists of spherical and aspherical mirrors. The use of an aspherical mirror allows the reflecting objective to have a numerical aperture (NA) of up to 0.99, which is close to the maximum possible NA of 1.03 in superfluid helium. The performance of the system at a temperature of 1.7 K was tested by recording a three-dimensional fluorescence image of individual quantum dots using excitation wavelengths (λex) of 532 nm and 635 nm. At 1.7 K, the microscope worked with achromatic and nearly diffraction-limited performance. The 1/e2 radius (Γ) of the point spread function of the reflecting objective in the lateral (xy) direction was 0.212 ± 0.008 μm at λex = 532 nm and was less than 1.2 times the simulated value for a perfectly polished objective. The radius Γ in the axial (z) direction was 0.91 ± 0.04 μm at λex = 532 nm and was less than 1.4 times the simulated value of Γ. The chromatic aberrations between the two wavelengths were one order of magnitude smaller than Γ in each direction. PMID:26239746

  16. Multiple wall-reflection effect in adaptive-array differential-phase reflectometry on QUEST

    NASA Astrophysics Data System (ADS)

    Idei, H.; Mishra, K.; Yamamoto, M. K.; Fujisawa, A.; Nagashima, Y.; Hamasaki, M.; Hayashi, Y.; Onchi, T.; Hanada, K.; Zushi, H.; QUEST Team

    2016-01-01

    A phased array antenna and Software-Defined Radio (SDR) heterodyne-detection systems have been developed for adaptive array approaches in reflectometry on the QUEST. In the QUEST device considered as a large oversized cavity, standing wave (multiple wall-reflection) effect was significantly observed with distorted amplitude and phase evolution even if the adaptive array analyses were applied. The distorted fields were analyzed by Fast Fourier Transform (FFT) in wavenumber domain to treat separately the components with and without wall reflections. The differential phase evolution was properly obtained from the distorted field evolution by the FFT procedures. A frequency derivative method has been proposed to overcome the multiple-wall reflection effect, and SDR super-heterodyned components with small frequency difference for the derivative method were correctly obtained using the FFT analysis.

  17. Dual/differential coherent anti-Stokes Raman scattering module for multiphoton microscopes with a femtosecond Ti:sapphire oscillator

    NASA Astrophysics Data System (ADS)

    Li, Bei; Borri, Paola; Langbein, Wolfgang

    2013-06-01

    In the last decade, coherent anti-Stokes Raman scattering (CARS) microscopy has emerged as a powerful multiphoton imaging technique offering label-free chemical sensitivity and high three-dimensional resolution. However, its widespread application in the life sciences has been hampered by the use of costly pulsed lasers, the existence of a nonresonant background requiring involved technical solutions for its efficient suppression, and the limited acquisition speed of multiplex techniques addressing several vibrational resonances, if improved chemical specificity is needed. We have recently reported a differential CARS technique (D-CARS), which simultaneously measures two vibrational frequencies, enhancing the chemical selectivity and sensitivity without introducing costly hardware, while maintaining fast acquisition. In this study, we demonstrate a compact, fully automated, cost-effective module, which integrates on hardware and software level with a commercial multiphoton microscope based on a single 100 fs Ti:Sapphire oscillator and enables D-CARS microscopy in a user-friendly format for applications in the life sciences.

  18. Dual/differential coherent anti-Stokes Raman scattering module for multiphoton microscopes with a femtosecond Ti:sapphire oscillator.

    PubMed

    Li, Bei; Borri, Paola; Langbein, Wolfgang

    2013-06-01

    In the last decade, coherent anti-Stokes Raman scattering (CARS) microscopy has emerged as a powerful multiphoton imaging technique offering label-free chemical sensitivity and high three-dimensional resolution. However, its widespread application in the life sciences has been hampered by the use of costly pulsed lasers, the existence of a nonresonant background requiring involved technical solutions for its efficient suppression, and the limited acquisition speed of multiplex techniques addressing several vibrational resonances, if improved chemical specificity is needed. We have recently reported a differential CARS technique (D-CARS), which simultaneously measures two vibrational frequencies, enhancing the chemical selectivity and sensitivity without introducing costly hardware, while maintaining fast acquisition. In this study, we demonstrate a compact, fully automated, cost-effective module, which integrates on hardware and software level with a commercial multiphoton microscope based on a single 100 fs Ti:Sapphire oscillator and enables D-CARS microscopy in a user-friendly format for applications in the life sciences.

  19. Comparison of the ability of quantitative parameters to differentiate surface texture of Atomic Force Microscope (AFM) images

    NASA Astrophysics Data System (ADS)

    Niedzielski, Bethany; Caragianis Broadbridge, Christine; DaPonte, John S.; Gherasimova, Maria

    2010-01-01

    The purpose of this study was to compare the ability of several texture analysis parameters to differentiate textured samples from a smooth control on images obtained with an Atomic Force Microscope (AFM). Surface roughness plays a major role in the realm of material science, especially in integrated electronic devices. As these devices become smaller and smaller, new materials with better electrical properties are needed. New materials with smoother surface morphology have been found to have superior electrical properties than their rougher counterparts. Therefore, in many cases surface texture is indicative of the electrical properties that material will have. Physical vapor deposition techniques such as Jet Vapor Deposition and Molecular Beam Epitaxy are being utilized to synthesize these materials as they have been found to create pure and uniform thin layers. For the current study, growth parameters were varied to produce a spectrum of textured samples. The focus of this study was the image processing techniques associated with quantifying surface texture. As a result of the limited sample size, there was no attempt to draw conclusions about specimen processing methods. The samples were imaged using an AFM in tapping mode. In the process of collecting images, it was discovered that roughness data was much better depicted in the microscope's "height" mode as opposed to "equal area" mode. The AFM quantified the surface texture of each image by returning RMS roughness and the first order histogram statistics of mean roughness, standard deviation, skewness, and kurtosis. Color images from the AFM were then processed on an off line computer running NIH ImageJ with an image texture plug in. This plug in produced another set of first order statistics computed from each images' histogram as well as second order statistics computed from each images' cooccurrence matrix. The second order statistics, which were originally proposed by Haralick, include contrast, angular

  20. Differential impact of Limnoperna fortunei-herbicide interaction between Roundup Max® and glyphosate on freshwater microscopic communities.

    PubMed

    Gattás, F; Vinocur, A; Graziano, M; Dos Santos Afonso, M; Pizarro, H; Cataldo, D

    2016-09-01

    Multiple anthropogenic stressors act simultaneously on the environment, with consequences different from those caused by single-stressor exposure. We investigated how the combination of the invasive mussel Limnoperna fortunei and a widely applied herbicide, Roundup Max®, affected freshwater microscopic communities and water quality. Further, we compared these results with those induced by the combination of the mussel and technical-grade glyphosate. We carried out a 34-day experiment in outdoor mesocosms, applying the following six treatments: 6 mg L(-1) of technical-grade glyphosate (G), the equivalent concentration of glyphosate in Roundup Max® (R), 100 mussels (M), the combination of mussels and herbicide either in the technical-grade or formulated form (MG and MR, respectively), and control (C). Herbicides significantly increased total phosphorus in water; R and MR showed greater initial total nitrogen and ammonium. R increased picoplankton abundance and caused an eightfold increase in phytoplankton, with high turbidity values; G had a lower effect on these variables. Herbicide-mussel combination induced an accelerated dissipation of glyphosate in water (MG 6.36 ± 0.83 mg G g DW(-1) day(-1) and MR 5.16 ± 1.26 mg G g DW(-1) day(-1)). A synergistic effect on ammonium was observed in MR but not in MG. MR and MG had an antagonistic effect on phytoplankton, which showed a drastic reduction due to grazing, as revealed by M. We provide evidence of differential effects of Roundup Max® and technical-grade glyphosate over water quality and microscopic communities, and in combination with mussels. However, in the combination of mussels and herbicides, mussels seem to play a leading role. In the presence of L. fortunei, the effects of higher nutrient availability provided by herbicides addition were counteracted by the filtration activity of mussels, which released nutrients, grazed on picoplankton and phytoplankton, and boosted the development of other

  1. High accuracy subwavelength distance measurements: A variable-angle standing-wave total-internal-reflection optical microscope

    SciTech Connect

    Haynie, A.; Min, T.-J.; Luan, L.; Mu, W.; Ketterson, J. B.

    2009-04-15

    We describe an extension of the total-internal-reflection microscopy technique that permits direct in-plane distance measurements with high accuracy (<10 nm) over a wide range of separations. This high position accuracy arises from the creation of a standing evanescent wave and the ability to sweep the nodal positions (intensity minima of the standing wave) in a controlled manner via both the incident angle and the relative phase of the incoming laser beams. Some control over the vertical resolution is available through the ability to scan the incoming angle and with it the evanescent penetration depth.

  2. Spectrophotometric Method for Differentiation of Human Skin Melanoma. I. Optical Diffuse Reflection Coefficient

    NASA Astrophysics Data System (ADS)

    Petruk, V. G.; Ivanov, A. P.; Kvaternyuk, S. M.; Barun, V. V.

    2016-03-01

    We have designed an experimental setup, based on two integrating spheres, that lets us measure the optical diffuse reflectance spectra (diffuse reflection coefficient vs. wavelength) of human skin quickly under clinical conditions in vivo. For the wavelength interval 520-1100 nm, we give the values of the diffuse reflection coefficient for healthy tissue, skin with a benign nevus, and skin with a malignant melanoma for a large group of test subjects. We experimentally established a number of wavelengths in the red-near IR region of the spectrum which can be used for early differential diagnosis of nevi and melanoma in patient cancer screening. According to the Kramer-Welch test, the probability of the diffuse reflection coefficient for skin with melanoma and a nevus having different distributions is >0.94, and at many wavelengths it is >0.999. By solving the inverse problem, we estimated the changes in a number of structural and biophysical parameters of the tissue on going from healthy skin to nevus and melanoma. The results obtained can provide a basis for developing a clinical approach to identifying the risk of malignant transformation of the skin before surgery and histological analysis of the tissue.

  3. Differential reflectivity (Z-DR) measurements of rainfall compared with ground-based disdrometer measurements

    NASA Technical Reports Server (NTRS)

    Direskeneli, H.; Seliga, T. A.; Aydin, K.

    1983-01-01

    The dual-polarization differential-reflectivity (Z-DR) radar technique of Seliga and Bringi (1976) is used to determine rainfall rates and drop sizes over a site located at a distance of 47.1 km, and the results are analyzed using the empirical calibration relations of Seliga et al. (1983) and compared with electromechanical-disdrometer measurements. The data are presented in graphs and found to be well correlated, demonstrating the validity of the Z-DR estimates and the improvement introduced by applying the empirical relations rather than an a priori drop-size distribution.

  4. Does skin hydration influence keratinocyte biology? In vivo evaluation of microscopic skin changes induced by moisturizers by means of reflectance confocal microscopy.

    PubMed

    Manfredini, Marco; Marco, Manfredini; Mazzaglia, Giovanna; Giovanna, Mazzaglia; Ciardo, Silvana; Silvana, Ciardo; Simonazzi, Silvia; Silvia, Simonazzi; Farnetani, Francesca; Francesca, Farnetani; Longo, Caterina; Caterina, Longo; Pellacani, Giovanni; Giovanni, Pellacani

    2013-08-01

    Skin hydration is defined as the water content of the epidermis and the dermis. In vivo reflectance confocal microscopy offers the opportunity to determine in vivo the kinetics of the skin after the application of topical products. To define confocal features associated with dry skin and assess the microscopic effects of different moisturizers. Ten healthy volunteers were enrolled for the study. Two different formulations were tested: petrolatum and a commercially available emulsion. Measurements were performed from baseline to 3 h after removal of the occlusion at regular time points. Nine confocal features were assessed: furrows' size, overall interkeratinocyte reflectance, furrows' morphology, scales, skin surface irregularity, non-rimmed dermal papillae, exocytosis, dermal inflammation and collagen type. Furrows' size and interkeratinocyte reflectance were also quantitated using a digital analysis. Stratum corneum capacitance was recorded. At baseline, RCM showed the presence of micro-scales and high skin surface irregularity score. After the application of topical products, the scale score decreased significantly; Furrow's size and Digital Furrow's Size had a marked and directly correlated decrement. Furrow's morphology and Epidermal Irregularity scores decreased from baseline to 30 min, the latter reaching a plateau in product application areas. Interestingly, interkeratinocyte reflectance progressively increased with the application of the topical products, while remained stable in the control area, confirmed by Digital Interkeratinocytes reflectance quantitation. RCM revealed that the changes involve the skin surface by reducing the micro-scales and epidermal irregularity. Even more interestingly, RCM showed that higher interkeratinocytes' brightness is seen for moisturizer, but not for the control area. This RCM finding could be linked to keratinocyte membrane protein exposure and/or substance release in the interkeratinocytic space. To sum up, RCM

  5. 50-nm-resolution full-field X-ray microscope without chromatic aberration using total-reflection imaging mirrors

    PubMed Central

    Matsuyama, Satoshi; Yasuda, Shuhei; Yamada, Jumpei; Okada, Hiromi; Kohmura, Yoshiki; Yabashi, Makina; Ishikawa, Tetsuya; Yamauchi, Kazuto

    2017-01-01

    X-ray spectromicroscopy with a full-field imaging technique is a powerful method for chemical analysis of heterogeneous complex materials with a nano-scale spatial resolution. For imaging optics, an X-ray reflective optical system has excellent capabilities with highly efficient, achromatic, and long-working-distance properties. An advanced Kirkpatrick–Baez geometry that combines four independent mirrors with elliptic and hyperbolic shapes in both horizontal and vertical directions was developed for this purpose, although the complexity of the system has a limited applicable range. Here, we present an optical system consisting of two monolithic imaging mirrors. Elliptic and hyperbolic shapes were formed on a single substrate to achieve both high resolution and sufficient stability. The mirrors were finished with a ~1-nm shape accuracy using elastic emission machining. The performance was tested at SPring-8 with a photon energy of approximately 10 keV. We could clearly resolve 50-nm features in a Siemens star without chromatic aberration and with high stability over 20 h. We applied this system to X-ray absorption fine structure spectromicroscopy and identified elements and chemical states in specimens of zinc and tungsten micron-size particles. PMID:28406227

  6. 50-nm-resolution full-field X-ray microscope without chromatic aberration using total-reflection imaging mirrors.

    PubMed

    Matsuyama, Satoshi; Yasuda, Shuhei; Yamada, Jumpei; Okada, Hiromi; Kohmura, Yoshiki; Yabashi, Makina; Ishikawa, Tetsuya; Yamauchi, Kazuto

    2017-04-13

    X-ray spectromicroscopy with a full-field imaging technique is a powerful method for chemical analysis of heterogeneous complex materials with a nano-scale spatial resolution. For imaging optics, an X-ray reflective optical system has excellent capabilities with highly efficient, achromatic, and long-working-distance properties. An advanced Kirkpatrick-Baez geometry that combines four independent mirrors with elliptic and hyperbolic shapes in both horizontal and vertical directions was developed for this purpose, although the complexity of the system has a limited applicable range. Here, we present an optical system consisting of two monolithic imaging mirrors. Elliptic and hyperbolic shapes were formed on a single substrate to achieve both high resolution and sufficient stability. The mirrors were finished with a ~1-nm shape accuracy using elastic emission machining. The performance was tested at SPring-8 with a photon energy of approximately 10 keV. We could clearly resolve 50-nm features in a Siemens star without chromatic aberration and with high stability over 20 h. We applied this system to X-ray absorption fine structure spectromicroscopy and identified elements and chemical states in specimens of zinc and tungsten micron-size particles.

  7. 50-nm-resolution full-field X-ray microscope without chromatic aberration using total-reflection imaging mirrors

    NASA Astrophysics Data System (ADS)

    Matsuyama, Satoshi; Yasuda, Shuhei; Yamada, Jumpei; Okada, Hiromi; Kohmura, Yoshiki; Yabashi, Makina; Ishikawa, Tetsuya; Yamauchi, Kazuto

    2017-04-01

    X-ray spectromicroscopy with a full-field imaging technique is a powerful method for chemical analysis of heterogeneous complex materials with a nano-scale spatial resolution. For imaging optics, an X-ray reflective optical system has excellent capabilities with highly efficient, achromatic, and long-working-distance properties. An advanced Kirkpatrick-Baez geometry that combines four independent mirrors with elliptic and hyperbolic shapes in both horizontal and vertical directions was developed for this purpose, although the complexity of the system has a limited applicable range. Here, we present an optical system consisting of two monolithic imaging mirrors. Elliptic and hyperbolic shapes were formed on a single substrate to achieve both high resolution and sufficient stability. The mirrors were finished with a ~1-nm shape accuracy using elastic emission machining. The performance was tested at SPring-8 with a photon energy of approximately 10 keV. We could clearly resolve 50-nm features in a Siemens star without chromatic aberration and with high stability over 20 h. We applied this system to X-ray absorption fine structure spectromicroscopy and identified elements and chemical states in specimens of zinc and tungsten micron-size particles.

  8. Geographical differentiation of dried lentil seed (Lens culinaris) samples using diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) and discriminant analysis.

    PubMed

    Kouvoutsakis, G; Mitsi, C; Tarantilis, P A; Polissiou, M G; Pappas, C S

    2014-02-15

    Diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) and discriminant analysis were used for the geographical differentiation of dried lentil seed (Lens culinaris) samples. Specifically, 18 Greek samples and nine samples imported from other countries were distinguished using the 2250-1720 and 1275-955 cm⁻¹ spectral regions. The differentiation is complete. The combination of DRIFTS and discriminant analysis enables simple, rapid, cheap and accurate differentiation of commercial lentil seeds in terms of geographical origin.

  9. Reflectance confocal microscope for imaging oral tissues in vivo, potentially with line scanning as a low-cost approach for clinical use

    NASA Astrophysics Data System (ADS)

    Peterson, Gary; Abeytunge, Sanjeewa; Eastman, Zachary; Rajadhyaksha, Milind

    2012-02-01

    Reflectance confocal microscopy with a line scanning approach potentially offers a smaller, simpler and less expensive approach than traditional methods of point scanning for imaging in living tissues. With one moving mechanical element (galvanometric scanner), a linear array detector and off-the-shelf optics, we designed a compact (102x102x76mm) line scanning confocal reflectance microscope (LSCRM) for imaging human tissues in vivo in a clinical setting. Custom-designed electronics, based on field programmable gate array (FPGA) logic has been developed. With 405 nm illumination and a custom objective lens of numerical aperture 0.5, lateral resolution was measured to be 0.8 um (calculated 0.64 um). The calculated optical sectioning is 3.2 um. Preliminary imaging shows nuclear and cellular detail in human skin and oral epithelium in vivo. Blood flow is also visualized in the deeper connective tissue (lamina propria) in oral mucosa. Since a line is confocal only in one dimension (parallel) but not in the other, the detection is more sensitive to multiply scattered out of focus background noise than in the traditional point scanning configuration. Based on the results of our translational studies thus far, a simpler, smaller and lower-cost approach based on a LSCRM appears to be promising for clinical imaging.

  10. A Differential Interference Contrast-Based Light Microscopic System for Laser Microsurgery and Optical Trapping of Selected Chromosomes during Mitosis In Vivo

    NASA Astrophysics Data System (ADS)

    Cole, Richard W.; Khodjakov, Alexey; Wright, William H.; Rieder, Conly L.

    1995-10-01

    Laser microsurgery and laser-generated optical force traps (optical tweezers) are both valuable light microscopic-based approaches for studying intra- and extracellular motility processes, including chromosome segregation during mitosis. Here we describe a system in use in our laboratory that allows living cells to be followed by high-resolution differential interference contrast (DIC) video-enhanced time-lapse light microscopy while selected mitotic organelles and spindle components are subjected to laser microsurgery and/or manipulation with an optical force trap. This system couples the output from two different Neodymium-YAG lasers to the same inverted light microscope equipped with both phase-contrast and de Senarmont compensation DIC optics, a motorized stage, and a high-resolution low-light-level CCD camera. Unlike similar systems using phase-contrast optics, our DIC-based system can image living cells in thin optical sections without contamination due to phase halos or out-of-focus object information. These advantages greatly facilitate laser-based light microscopic studies on mitotic organelles and components, including spindle poles (centrosomes) and kinetochores, which are at or below the resolution limit of the light microscope and buried within a large complex structure. When used in conjunction with image processing and high-resolution object-tracking techniques, our system provides new information on the roles that kinetochores and spindle microtubules play during chromosome segregation in plant and animal cells.

  11. Surface plasmon resonance spectroscopy of single bowtie nano-antennas using a differential reflectivity method

    NASA Astrophysics Data System (ADS)

    Kaniber, M.; Schraml, K.; Regler, A.; Bartl, J.; Glashagen, G.; Flassig, F.; Wierzbowski, J.; Finley, J. J.

    2016-03-01

    We report on the structural and optical properties of individual bowtie nanoantennas both on glass and semiconducting GaAs substrates. The antennas on glass (GaAs) are shown to be of excellent quality and high uniformity reflected by narrow size distributions with standard deviations for the triangle and gap size of = 4.5 nm = 2.6 nm and = 5.4 nm = 3.8 nm, respectively. The corresponding optical properties of individual nanoantennas studied by differential reflection spectroscopy show a strong reduction of the localised surface plasmon polariton resonance linewidth from 0.21 eV to 0.07 eV upon reducing the antenna size from 150 nm to 100 nm. This is attributed to the absence of inhomogeneous broadening as compared to optical measurements on nanoantenna ensembles. The inter-particle coupling of an individual bowtie nanoantenna, which gives rise to strongly localised and enhanced electromagnetic hotspots, is demonstrated using polarization-resolved spectroscopy, yielding a large degree of linear polarization of ρmax ~ 80%. The combination of highly reproducible nanofabrication and fast, non-destructive and non-contaminating optical spectroscopy paves the route towards future semiconductor-based nano-plasmonic circuits, consisting of multiple photonic and plasmonic entities.

  12. Surface plasmon resonance spectroscopy of single bowtie nano-antennas using a differential reflectivity method

    PubMed Central

    Kaniber, M.; Schraml, K.; Regler, A.; Bartl, J.; Glashagen, G.; Flassig, F.; Wierzbowski, J.; Finley, J. J.

    2016-01-01

    We report on the structural and optical properties of individual bowtie nanoantennas both on glass and semiconducting GaAs substrates. The antennas on glass (GaAs) are shown to be of excellent quality and high uniformity reflected by narrow size distributions with standard deviations for the triangle and gap size of = 4.5 nm = 2.6 nm and = 5.4 nm = 3.8 nm, respectively. The corresponding optical properties of individual nanoantennas studied by differential reflection spectroscopy show a strong reduction of the localised surface plasmon polariton resonance linewidth from 0.21 eV to 0.07 eV upon reducing the antenna size from 150 nm to 100 nm. This is attributed to the absence of inhomogeneous broadening as compared to optical measurements on nanoantenna ensembles. The inter-particle coupling of an individual bowtie nanoantenna, which gives rise to strongly localised and enhanced electromagnetic hotspots, is demonstrated using polarization-resolved spectroscopy, yielding a large degree of linear polarization of ρmax ~ 80%. The combination of highly reproducible nanofabrication and fast, non-destructive and non-contaminating optical spectroscopy paves the route towards future semiconductor-based nano-plasmonic circuits, consisting of multiple photonic and plasmonic entities. PMID:27005986

  13. Early detection and differentiation of venous and arterial occlusion in skin flaps using visible diffuse reflectance spectroscopy and autofluorescence spectroscopy

    PubMed Central

    Zhu, Caigang; Chen, Shuo; Chui, Christopher Hoe-Kong; Tan, Bien-Keem; Liu, Quan

    2016-01-01

    Our previous preclinical study demonstrated that both visible diffuse reflectance and autofluorescence spectroscopy, each of which yields a different set of physiological information, can predict skin flap viability with high accuracy in a MacFarlane rat dorsal skin flap model. In this report, we further evaluated our technique for the early detection and differentiation of venous occlusion and arterial occlusion in a rat groin flap model. We performed both diffuse reflectance and autofluorescence measurements on the skin flap model and statistically differentiated between flaps with and without occlusions as well as between flaps with venous occlusion and those with arterial occlusion based on these non-invasive optical measurements. Our preliminary results suggested that visible diffuse reflectance and autofluorescence spectroscopy can be potentially used clinically to detect both venous and arterial occlusion and differentiate one from the other accurately at an early time point. PMID:26977363

  14. Note: refractive index sensing of turbid media by differentiation of the reflectance profile: does error-correction work?

    PubMed

    Goyal, K G; Dong, M L; Kane, D G; Makkar, S S; Worth, B W; Bali, L M; Bali, S

    2012-08-01

    A widely used method for determining refractive index postulates that the derivative of the angular profile for light reflected from the sample is maximum at the critical angle for total internal reflection (TIR). It is well-known that in turbid media this "differentiation method" yields errors in refractive index. Unexplained anomalies in previous error-calculations are eliminated if one uses a recent model of TIR which departs from traditional Fresnel theory. However we find that, in practical situations, the refractive index obtained by differentiation even after error-correction is significantly different from the best estimate for the refractive index obtained by curve-fitting the reflectance data. Thus the differentiation method lacks scientific validity in turbid media.

  15. Early detection and differentiation of venous and arterial occlusion in skin flaps using visible diffuse reflectance spectroscopy and autofluorescence spectroscopy.

    PubMed

    Zhu, Caigang; Chen, Shuo; Chui, Christopher Hoe-Kong; Tan, Bien-Keem; Liu, Quan

    2016-02-01

    Our previous preclinical study demonstrated that both visible diffuse reflectance and autofluorescence spectroscopy, each of which yields a different set of physiological information, can predict skin flap viability with high accuracy in a MacFarlane rat dorsal skin flap model. In this report, we further evaluated our technique for the early detection and differentiation of venous occlusion and arterial occlusion in a rat groin flap model. We performed both diffuse reflectance and autofluorescence measurements on the skin flap model and statistically differentiated between flaps with and without occlusions as well as between flaps with venous occlusion and those with arterial occlusion based on these non-invasive optical measurements. Our preliminary results suggested that visible diffuse reflectance and autofluorescence spectroscopy can be potentially used clinically to detect both venous and arterial occlusion and differentiate one from the other accurately at an early time point.

  16. Tissue differentiation by diffuse reflectance spectroscopy for automated oral and maxillofacial laser surgery: ex vivo pilot study

    NASA Astrophysics Data System (ADS)

    Zam, Azhar; Stelzle, Florian; Tangermann-Gerk, Katja; Adler, Werner; Nkenke, Emeka; Schmidt, Michael; Douplik, Alexandre

    2010-02-01

    Remote laser surgery lacks of haptic feedback during the laser ablation of tissue. Hence, there is a risk of iatrogenic damage or destruction of anatomical structures like nerves or salivary glands. Diffuse reflectance spectroscopy provides a straightforward and simple approach for optical tissue differentiation. We measured diffuse reflectance from seven various tissue types ex vivo. We applied Linear Discriminant Analysis (LDA) to differentiate the seven tissue types and computed the area under the ROC curve (AUC). Special emphasis was taken on the identification of nerves and salivary glands as the most crucial tissue for maxillofacial surgery. The results show a promise for differentiating tissues as guidance for oral and maxillofacial laser surgery by means of diffuse reflectance.

  17. Differential gene expression profiling in aggressive bladder transitional cell carcinoma compared to the adjacent microscopically normal urothelium by microdissection-SMART cDNA PCR-SSH.

    PubMed

    Wang, H T; Ma, F L; Ma, X B; Han, R F; Zhang, Y B; Chang, J W

    2006-01-01

    Identifying novel and known genes that are differentially expressed in aggressive bladder transitional cell carcinoma (BTCC) has important implications in understanding the biology of bladder tumorigenesis and developing new diagnostic and therapeutic agents. In this study we identified the differential gene expression profiles comparing tumor to the adjacent microscopically normal mucosa by manual microdissection on frozen sections. The RNAs extracted from microdissected tissues were amplified by SMART cDNA PCR technology to generate forward subtractive cDNA library by suppressive subtractive hybridization (SSH). We obtained 376 positive clones, one hundred clones of aggressive BTCC subtracted cDNA library were selected at random and inserts were reamplified by PCR. After differential screening by reverse dot blotting, 73 positive clones, that contend inserts putatively upregulated in aggressive BTCC, were further analysed by DNA sequencing, GenBank and EST database searching. Sequencing results showed that 66 clones stand for 23 known genes and 7 clones for three new EST (Genbank number: DN236875, DN236874 and DN236873). In conclusion, microdissection-SMART cDNA PCR-SSH allowed for an efficient way to identify aggressive BTCC-specific differential expressed genes that may potentially be involved in the carcinogenesis and/or progression of aggressive BTCC. These differentially expressed genes may be of potential utility as therapeutic and diagnostic targets for aggressive BTCC.

  18. Columns of differential reflectivity: a precursor for storm evolution and convective rain

    NASA Astrophysics Data System (ADS)

    Troemel, S.; Diederich, M.; Kumjian, M. R.; Picca, J. C.; Simmer, C.

    2012-12-01

    Nowcasting aims at providing accurate information about weather hazards related to convection at a very high refresh rate well suited for fast evolving convective systems. Polarimetric weather radars arise as a key tool to provide "seamless" analysis and nowcast of convective risk to aviation, because of their ability to observe 3dimensional storm structure, evolution, microphysical processes, and generated precipitation. Columns of differential reflectivity ZDR measured by polarimetric weather radars are prominent signatures associated with thunderstorm updrafts. Since greater vertical velocities can loft larger drops and water-coated ice particles to higher altitudes above the environmental freezing level, the integrated ZDR column above the freezing level increases with increasing updraft intensity. Frequently, they can extend several kilometers above the environmental freezing level. These positive ZDR values above the environmental freezing level point to the presence of large, oblate raindrops and perhaps water-coated hailstones and graupel. Analyses on the informative content of ZDR columns as precursor for storm evolution will be presented based on both the X-band polarimetric data collected by the twin radars (XPol Bonn and XPol Jülich) in the Bonn area, Germany, and volume radar data collected with the S-band KOUN radar, in Norman, Oklahoma. In order to derive the ZDR column product, radar volume data is interpolated onto a three-dimensional Cartesian (x,y,z) grid and then, for each (x,y) coordinate, the number of vertical grid boxes above the freezing level containing ZDR values in excess of a predetermined threshold (=1dB) are counted. The ZDR column product is simply a count of the number of grid boxes, which can be converted into "ZDR column volume" by simply multiplying the count by the dimension ΔxΔyΔz of the grid box. Interdependencies between the volumes of ZDR columns above the environmental freezing level, precipitation near the surface, the

  19. Disdrometer measurements during a unique rainfall event in central Illinois and their implication for differential reflectivity radar observations

    NASA Technical Reports Server (NTRS)

    Seliga, T. A.; Aydin, K.; Direskeneli, H.

    1983-01-01

    Understanding of the natural variability of rainfall is essential in order to assess radar's ability to estimate rainfall characteristics such as rainfall rate, rainfall water content and drop size distribution parameters. The two most useful measurements of rainfall for this purpose derive from ground-based disdrometers and aircraft-borne drop size spectrometers. Accordingly, this paper examines a time series of disdrometer measurements obtained during a unique rainfall event which occurred in central Illinois on October 6, 1982. The measurements are used to predict the behavior of radar observables (reflectivity factor and differential reflectivity) for application to the estimation of rainfall parameters. The results support previous theoretical predictions (Seliga and Bringi, 1976) and experimental results (Seliga et al., 1979, 1981; Bringi et al., 1982; Hall et al., 1980; Goddard et al., 1982) based upon the differential reflectivity (ZDR) radar technique.

  20. Diffuse reflectance spectroscopy can differentiate high grade and low grade prostatic carcinoma.

    PubMed

    Werahera, Priya N; Jasion, Edward A; David Crawford, E; Lucia, M Scott; van Bokhoven, Adrie; Sullivan, Holly T; Kim, Fernando J; Maroni, Paul D; David Port, J; Daily, John W; Rosa, Francisco G La; Werahera, Priya N; Jasion, Edward A; Crawford, E David; Lucia, M Scott; van Bokhoven, Adrie; Sullivan, Holly T; Kim, Fernando J; Maroni, Paul D; Port, J David; Daily, John W; La Rosa, Francisco G; Daily, John W; Van Bokhoven, Adrie; Crawford, E David; Port, J David; Werahera, Priya N; Lucia, M Scott; Sullivan, Holly T; Maroni, Paul D; Jasion, Edward A; La Rosa, Francisco G; Kim, Fernando J

    2016-08-01

    Prostate tumors are graded by the revised Gleason Score (GS) which is the sum of the two predominant Gleason grades present ranging from 6-10. GS 6 cancer exclusively with Gleason grade 3 is designated as low grade (LG) and correlates with better clinical prognosis for patients. GS >7 cancer with at least one of the Gleason grades 4 and 5 is designated as HG indicate worse prognosis for patients. Current transrectal ultrasound guided prostate biopsies often fail to correctly diagnose HG prostate cancer due to sampling errors. Diffuse reflectance spectra (DRS) of biological tissue depend on tissue morphology and architecture. Thus, DRS could potentially differentiate between HG and LG prostatic carcinoma. A 15-gauge optical biopsy needle was prototyped to take prostate biopsies after measuring DRS with a laboratory fluorometer. This needle has an optical sensor that utilizes 8×100 μm optical fibers for tissue excitation and a single 200 μm central optical fiber to measure DRS. Tissue biopsy cores were obtained from 20 surgically excised prostates using this needle after measuring DRS at 5 nm intervals between 500-700 nm wavelengths. Tissue within a measurement window was histopathologically classified as either benign, LG, or HG and correlated with DRS. Partial least square analysis of DRS identified principal components (PC) as potential classifiers. Statistically significant PCs (p<;0.05) were tested for their ability to classify biopsy tissue using support vector machine and leave-one-out cross validation method. There were 29 HG and 49 LG cancers among 187 biopsy cores included in the study. Study results show 76% sensitivity, 80% specificity, 93% negative predictive value, and 50% positive predictive value for HG versus benign, and 76%, 73%, 84%, and 63%, for HG versus LG prostate tissue classification. DRS failed to diagnose 7/29 (24%) HG cancers. This study demonstrated that an optical biopsy needle guided by DRS has sufficient accuracy to differentiate HG

  1. HIGH TEMPERATURE MICROSCOPE AND FURNACE

    DOEpatents

    Olson, D.M.

    1961-01-31

    A high-temperature microscope is offered. It has a reflecting optic situated above a molten specimen in a furnace and reflecting the image of the same downward through an inert optic member in the floor of the furnace, a plurality of spaced reflecting plane mirrors defining a reflecting path around the furnace, a standard microscope supported in the path of and forming the end terminus of the light path.

  2. Reflecting Solutions of High Order Elliptic Differential Equations in Two Independent Variables Across Analytic Arcs. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Carleton, O.

    1972-01-01

    Consideration is given specifically to sixth order elliptic partial differential equations in two independent real variables x, y such that the coefficients of the highest order terms are real constants. It is assumed that the differential operator has distinct characteristics and that it can be factored as a product of second order operators. By analytically continuing into the complex domain and using the complex characteristic coordinates of the differential equation, it is shown that its solutions, u, may be reflected across analytic arcs on which u satisfies certain analytic boundary conditions. Moreover, a method is given whereby one can determine a region into which the solution is extensible. It is seen that this region of reflection is dependent on the original domain of difinition of the solution, the arc and the coefficients of the highest order terms of the equation and not on any sufficiently small quantities; i.e., the reflection is global in nature. The method employed may be applied to similar differential equations of order 2n.

  3. Neural differentiation of transplanted neural stem cells in a rat model of striatal lacunar infarction: light and electron microscopic observations

    PubMed Central

    Muñetón-Gómez, Vilma C.; Doncel-Pérez, Ernesto; Fernandez, Ana P.; Serrano, Julia; Pozo-Rodrigálvarez, Andrea; Vellosillo-Huerta, Lara; Taylor, Julian S.; Cardona-Gómez, Gloria P.; Nieto-Sampedro, Manuel; Martínez-Murillo, Ricardo

    2012-01-01

    The increased risk and prevalence of lacunar stroke and Parkinson's disease (PD) makes the search for better experimental models an important requirement for translational research. In this study we assess ischemic damage of the nigrostriatal pathway in a model of lacunar stroke evoked by damaging the perforating arteries in the territory of the substantia nigra (SN) of the rat after stereotaxic administration of endothelin-1 (ET-1), a potent vasoconstrictor peptide. We hypothesized that transplantation of neural stem cells (NSCs) with the capacity of differentiating into diverse cell types such as neurons and glia, but with limited proliferation potential, would constitute an alternative and/or adjuvant therapy for lacunar stroke. These cells showed neuritogenic activity in vitro and a high potential for neural differentiation. Light and electron microscopy immunocytochemistry was used to characterize GFP-positive neurons derived from the transplants. 48 h after ET-1 injection, we characterized an area of selective degeneration of dopaminergic neurons within the nigrostriatal pathway characterized with tissue necrosis and glial scar formation, with subsequent behavioral signs of Parkinsonism. Light microscopy showed that grafted cells within the striatal infarction zone differentiated with a high yield into mature glial cells (GFAP-positive) and neuron types present in the normal striatum. Electron microscopy revealed that NSCs-derived neurons integrated into the host circuitry establishing synaptic contacts, mostly of the asymmetric type. Astrocytes were closely associated with normal small-sized blood vessels in the area of infarct, suggesting a possible role in the regulation of the blood brain barrier and angiogenesis. Our results encourage the use of NSCs as a cell-replacement therapy for the treatment of human vascular Parkinsonism. PMID:22876219

  4. Infrared microscope inspection apparatus

    DOEpatents

    Forman, S.E.; Caunt, J.W.

    1985-02-26

    Apparatus and system for inspecting infrared transparents, such as an array of photovoltaic modules containing silicon solar cells, includes an infrared microscope, at least three sources of infrared light placed around and having their axes intersect the center of the object field and means for sending the reflected light through the microscope. The apparatus is adapted to be mounted on an X-Y translator positioned adjacent the object surface. 4 figs.

  5. Infrared microscope inspection apparatus

    DOEpatents

    Forman, Steven E.; Caunt, James W.

    1985-02-26

    Apparatus and system for inspecting infrared transparents, such as an array of photovoltaic modules containing silicon solar cells, includes an infrared microscope, at least three sources of infrared light placed around and having their axes intersect the center of the object field and means for sending the reflected light through the microscope. The apparatus is adapted to be mounted on an X-Y translator positioned adjacent the object surface.

  6. Comparison of the Sysmex XT-2000iV with microscopic differential counts of canine bone marrow.

    PubMed

    Pernecker, Iris; Bauer, Natali B; Johannes, Sigrid; Ginder, Melanie; Harleman, Johannes H; Moritz, Andreas

    2017-03-01

    Canine bone marrow is frequently assessed in the advanced preclinical research environment. Automated analysis provides time savings and objectivity over the gold standard of microscopic (cytologic) evaluation. We compared the analysis of 90 canine bone marrow samples by the Sysmex XT-2000iV hematology analyzer (Sysmex Corp., Kobe, Japan) with cytologic evaluation. Gates for cell populations were created in the system's WBC/BASO channel. Variables "total nucleated red blood cells" (total_NRBC), "poly- and orthochromatic nucleated red blood cells" (poly_orth_NRBC), "total neutrophils" (total_NEUT), "mature neutrophils" (mature_NEUT), and myeloid-to-erythroid (M:E) ratio were compared with cytologic evaluation. Intra-assay repeatability and total error (TE) were calculated for both methods. Intra-assay repeatability was 0.95-2.48% for the XT-2000iV and 8.32-23.23% for cytology. Observed TE for the automated measurement was 5.16-46.8% and for cytology 22.70-76.74%. Spearman rank correlation was excellent for M:E ratio (0.91) and fair for the other populations (0.65-0.71). Absolute bias for M:E ratio was low (-0.114). A negative absolute bias of -7.71% for the XT-2000iV was found for poly_orth_NRBC, whereas the bias was positive for total_NEUT (7.10%) and mature_NEUT (14.67%). M:E ratio of canine bone marrow samples can be precisely determined using the Sysmex XT-2000iV WBC/BASO channel. Total_NRBC, poly_orth_NRBC, total_NEUT, and mature_NEUT can be estimated rapidly. With distinctly lower coefficient of variation and observed TE compared with cytology, automated measurement provides advantages in terms of standardization, and it is suited to the advanced preclinical research environment where large numbers of samples are investigated.

  7. Valence band gaps and plasma energies for galena, sphalerite, and chalcopyrite natural minerals using differential optical reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Todoran, R.; Todoran, D.; Szakacs, Zs.

    2015-12-01

    The paper presents the determinations of the valence band gaps and plasma energies of the galena, sphalerite and chalcopyrite natural minerals. The work was carried out using differential optical reflectance spectroscopy of the clean mineral surfaces. The determination of the optical properties such as refractive index, real part of the complex dielectric constant and the location of certain van Hove singularities, was carried out using the Kramers-Kronig formalism.

  8. Microscope basics.

    PubMed

    Sluder, Greenfield; Nordberg, Joshua J

    2013-01-01

    This chapter provides information on how microscopes work and discusses some of the microscope issues to be considered in using a video camera on the microscope. There are two types of microscopes in use today for research in cell biology-the older finite tube-length (typically 160mm mechanical tube length) microscopes and the infinity optics microscopes that are now produced. The objective lens forms a magnified, real image of the specimen at a specific distance from the objective known as the intermediate image plane. All objectives are designed to be used with the specimen at a defined distance from the front lens element of the objective (the working distance) so that the image formed is located at a specific location in the microscope. Infinity optics microscopes differ from the finite tube-length microscopes in that the objectives are designed to project the image of the specimen to infinity and do not, on their own, form a real image of the specimen. Three types of objectives are in common use today-plan achromats, plan apochromats, and plan fluorite lenses. The concept of mounting video cameras on the microscope is also presented in the chapter.

  9. Multiphoton microscopic imaging of histological sections without hematoxylin and eosin staining differentiates carcinoma in situ lesion from normal oesophagus

    NASA Astrophysics Data System (ADS)

    Chen, Jianxin; Xu, Jian; Kang, Deyong; Xu, Meifang; Zhuo, Shuangmu; Zhu, Xiaoqin; Jiang, Xingshan

    2013-10-01

    Multiphoton microscopy (MPM) has become a powerful, important tool for tissues imaging at the molecular level. In this paper, this technique was extended to histological investigations, differentiating carcinoma in situ (CIS) lesion from normal oesophagus by imaging histological sections without hematoxylin and eosin (H&E) staining. The results show that the histology procedures of dehydration, paraffin embedding, and de-paraffinizing highlighted two photon excited fluorescence of cytoplasm and nucleolus of epithelial cell and collagen in stroma. MPM has the ability to identify the characteristics of CIS lesion including changes of squamous cells and full epithelium, identification of basement membrane, especially prominent nucleolus. The studies described here show that MPM has the potential for future retrospective studies of tumor staging by employing on histological section specimens without H&E staining.

  10. [Microscopic colitis].

    PubMed

    Bohr, Johan

    2002-02-11

    Microscopic colitis is an umbrella term for a newly described group of colitides, belonging to the inflammatory bowel diseases, which are only diagnosable by microscopic evaluation of a macroscopically normal colon mucosa. Collagenous colitis and lymphocytic colitis are the most common of these colitides. Microscopic colitis is characterised clinically by chronic non-bloody watery diarrhoea. Crampy abdominal pain, nocturnal diarrhoea, urgency, and initial weight loss are usual. Concomitant diseases of autoimmune origin and arthralgia are commonly seen. Treatment of microscopic colitis follows the guidelines for treatment of other inflammatory bowel diseases, but a substantial part of the patients with microscopic colitis enter spontaneous remission after some years. A minor part, however, have very troublesome symptoms and are almost refractory to treatment. Microscopic colitis has apparently no malignant potential.

  11. Wave optics simulation of atmospheric turbulence and reflective speckle effects in CO{sub 2} differential absorption LIDAR (DIAL)

    SciTech Connect

    Nelson, D.H.; Petrin, R.R.; MacKerrow, E.P.; Schmitt, M.J.; Quick, C.R.; Zardecki, A.; Porch, W.M.; Whitehead, M.; Walters, D.L.

    1998-09-01

    The measurement sensitivity of CO{sub 2} differential absorption LIDAR (DIAL) can be affected by a number of different processes. The authors address the interaction of two of these processes: effects due to beam propagation through atmospheric turbulence and effects due to reflective speckle. Atmospheric turbulence affects the beam distribution of energy and phase on target. These effects include beam spreading, beam wander and scintillation which can result in increased shot-to-shot signal noise. In addition, reflective speckle alone has a major impact on the sensitivity of CO{sub 2} DIAL. The interaction of atmospheric turbulence and reflective speckle is of great importance in the performance of a DIAL system. A Huygens-Fresnel wave optics propagation code has previously been developed at the Naval Postgraduate School that models the effects of atmospheric turbulence as propagation through a series of phase screens with appropriate atmospheric statistical characteristics. This code has been modified to include the effects of reflective speckle. The performance of this modified code with respect to the combined effects of atmospheric turbulence and reflective speckle is examined. Results are compared with a combination of experimental data and analytical models.

  12. Community Agricultural Processing Services: A Reflection of Urban Differentiation or County Agricultural Structure.

    ERIC Educational Resources Information Center

    Moxley, Robert L.; Calloway, Michael O.

    Questionnaire data from 81 North Carolina communities were analyzed in 1981 to test the hypothesis that 5 institutional subcategories (education, general community services, transportation, agricultural services, and health and sanitation) exhibit the underlying characteristic of unidimensionality and that they reflect comparable levels of…

  13. Two Configurations for Accessing Classroom Computers: Differential Impact on Students' Critical Reflections and Their Empowerment

    ERIC Educational Resources Information Center

    Solhaug, T.

    2009-01-01

    The context of this article is the new technological environment and the struggle to use meaningful teaching practices in Norwegian schools. Students' critical reflections in two different technological learning environments in six upper secondary schools are compared. Three of these schools offer Internet-connected computers in special computer…

  14. Community Agricultural Processing Services: A Reflection of Urban Differentiation or County Agricultural Structure.

    ERIC Educational Resources Information Center

    Moxley, Robert L.; Calloway, Michael O.

    Questionnaire data from 81 North Carolina communities were analyzed in 1981 to test the hypothesis that 5 institutional subcategories (education, general community services, transportation, agricultural services, and health and sanitation) exhibit the underlying characteristic of unidimensionality and that they reflect comparable levels of…

  15. Two Configurations for Accessing Classroom Computers: Differential Impact on Students' Critical Reflections and Their Empowerment

    ERIC Educational Resources Information Center

    Solhaug, T.

    2009-01-01

    The context of this article is the new technological environment and the struggle to use meaningful teaching practices in Norwegian schools. Students' critical reflections in two different technological learning environments in six upper secondary schools are compared. Three of these schools offer Internet-connected computers in special computer…

  16. Testing leaf multispectral reflectance data as input into random forest to differentiate velvetleaf from soybean

    USDA-ARS?s Scientific Manuscript database

    Velvetleaf (Abutilon theophrasti Medic.) infestations negatively impact row crop production throughout the United States and Canada’s eastern provinces. To implement management strategies to control velvetleaf, managers need tools for differentiating it from crop plants. 5Band, 7Band, 8Band, and ...

  17. Culture adaptation alters transcriptional hierarchies among single human embryonic stem cells reflecting altered patterns of differentiation.

    PubMed

    Gokhale, Paul J; Au-Young, Janice K; Dadi, SriVidya; Keys, David N; Harrison, Neil J; Jones, Mark; Soneji, Shamit; Enver, Tariq; Sherlock, Jon K; Andrews, Peter W

    2015-01-01

    We have used single cell transcriptome analysis to re-examine the substates of early passage, karyotypically Normal, and late passage, karyotypically Abnormal ('Culture Adapted') human embryonic stem cells characterized by differential expression of the cell surface marker antigen, SSEA3. The results confirmed that culture adaptation is associated with alterations to the dynamics of the SSEA3(+) and SSEA3(-) substates of these cells, with SSEA3(-) Adapted cells remaining within the stem cell compartment whereas the SSEA3(-) Normal cells appear to have differentiated. However, the single cell data reveal that these substates are characterized by further heterogeneity that changes on culture adaptation. Notably the Adapted population includes cells with a transcriptome substate suggestive of a shift to a more naïve-like phenotype in contrast to the cells of the Normal population. Further, a subset of the Normal SSEA3(+) cells expresses genes typical of endoderm differentiation, despite also expressing the undifferentiated stem cell genes, POU5F1 (OCT4) and NANOG, whereas such apparently lineage-primed cells are absent from the Adapted population. These results suggest that the selective growth advantage gained by genetically variant, culture adapted human embryonic stem cells may derive in part from a changed substate structure that influences their propensity for differentiation.

  18. Differentiating cancerous tissues from noncancerous tissues using single-fiber reflectance spectroscopy with different fiber diameters

    NASA Astrophysics Data System (ADS)

    Sircan-Kuçuksayan, Aslinur; Denkceken, Tuba; Canpolat, Murat

    2015-11-01

    Elastic light-scattering spectra acquired with single-fiber optical probes with diameters of 100, 200, 400, 600, 800, 1000, 1200, and 1500 μm were used to differentiate cancerous from noncancerous prostate tissues. The spectra were acquired ex vivo on 24 excised prostate tissue samples collected from four patients. For each probe, the spectra and histopathology results were compared in order to investigate the correlation between the core diameters of the single-fiber optical probe and successful differentiation between cancerous and noncancerous prostate tissues. The spectra acquired using probes with a fiber core diameter of 400 μm or smaller successfully differentiated cancerous from noncancerous prostate tissues. Next, the spectra were acquired from monosized polystyrene microspheres with a diameter of 5.00±0.01 μm to investigate the correlation between the core diameters of the probes and the Mie oscillations on the spectra. Monte Carlo simulations of the light distribution of the tissue phantoms were run to interrogate whether the light detected by the probes with different fiber core diameters was in the ballistic or diffusive regime. If the single-fiber optical probes detect light in the ballistic regime, the spectra can be used to differentiate between cancerous and noncancerous tissues.

  19. [Dissociation (conversion) - malingering - antisocial personality disorder: differential diagnostic reflection on the basis of a case study].

    PubMed

    Rothuber, Helfried; Mitterauer, Bernhard

    2011-01-01

    In this case report we refer to the big challenge of making a diagnosis in a deliberate malingering in the field of mental disorders. We specifically describe the difficulty regarding the differentiation between a conversion disorder and malingering of a serial delinquent. For such a person avoiding criminal persecution is one of the most frequent reason to deceitfully simulate a mental illness. In this field, symptoms of conversion disorders exceed the average; furthermore, a great number of organic-neurological illnesses may appear to be very similar to a conversion disorder or in many cases a neurological disorder can actually be detected in the course of a somatic examination. A further obstacle for the differential diagnosis can be seen in the difficulty to discern it from factitious disorders. However, it is quite possible to discern the deliberate malingering of a mental disorder from a conversion disorder by means of the diligent diagnosis of a competent and experienced doctor/assessor who specialises.

  20. Code Validation for Eddy Current Modeling: Tube Inspection with Reflection Differential Probes

    SciTech Connect

    Schumm, A.; Nakagawa, N.

    2005-04-09

    Simulation results of the eddy current modeling code ECSIM on an Inconel tube mock-up were compared to existing experimental results on inner and outer circumferential notches inspected at two different frequencies, observing the influence of a geometrical effect such as tube thickness. The EC probe used for this setup represented a number of difficulties, such as a ferrite core for the excitation coil and a differential pickup coil arrangement with a small inner diameter. The results were instructive, showing that special care must be taken to generate highly symmetrical meshes, as minor differences are amplified by the differential setup. We present qualitative and quantitative results and focus on the lessons learned from this code validation exercise.

  1. Mid-fusiform activation during object discrimination reflects the process of differentiating structural descriptions.

    PubMed

    Liu, Xun; Steinmetz, Nicholas A; Farley, Alison B; Smith, Charles D; Joseph, Jane E

    2008-09-01

    The present study explored constraints on mid-fusiform activation during object discrimination. In three experiments, participants performed a matching task on simple line configurations, nameable objects, three dimensional (3-D) shapes, and colors. Significant bilateral mid-fusiform activation emerged when participants matched objects and 3-D shapes, as compared to when they matched two-dimensional (2-D) line configurations and colors, indicating that the mid-fusiform is engaged more strongly for processing structural descriptions (e.g., comparing 3-D volumetric shape) than perceptual descriptions (e.g., comparing 2-D or color information). In two of the experiments, the same mid-fusiform regions were also modulated by the degree of structural similarity between stimuli, implicating a role for the mid-fusiform in fine differentiation of similar visual object representations. Importantly, however, this process of fine differentiation occurred at the level of structural, but not perceptual, descriptions. Moreover, mid-fusiform activity was more robust when participants matched shape compared to color information using the identical stimuli, indicating that activity in the mid-fusiform gyrus is not driven by specific stimulus properties, but rather by the process of distinguishing stimuli based on shape information. Taken together, these findings further clarify the nature of object processing in the mid-fusiform gyrus. This region is engaged specifically in structural differentiation, a critical component process of object recognition and categorization.

  2. Interference Confocal Microscope Integrated with Spatial Phase Shifter.

    PubMed

    Wang, Weibo; Gu, Kang; You, Xiaoyu; Tan, Jiubin; Liu, Jian

    2016-08-24

    We present an interference confocal microscope (ICM) with a new single-body four-step simultaneous phase-shifter device designed to obtain high immunity to vibration. The proposed ICM combines the respective advantages of simultaneous phase shifting interferometry and bipolar differential confocal microscopy to obtain high axis resolution, large dynamic range, and reduce the sensitivity to vibration and reflectance disturbance seamlessly. A compact single body spatial phase shifter is added to capture four phase-shifted interference signals simultaneously without time delay and construct a stable and space-saving simplified interference confocal microscope system. The test result can be obtained by combining the interference phase response and the bipolar property of differential confocal microscopy without phase unwrapping. Experiments prove that the proposed microscope is capable of providing stable measurements with 1 nm of axial depth resolution for either low- or high-numerical aperture objective lenses.

  3. Interference Confocal Microscope Integrated with Spatial Phase Shifter

    PubMed Central

    Wang, Weibo; Gu, Kang; You, Xiaoyu; Tan, Jiubin; Liu, Jian

    2016-01-01

    We present an interference confocal microscope (ICM) with a new single-body four-step simultaneous phase-shifter device designed to obtain high immunity to vibration. The proposed ICM combines the respective advantages of simultaneous phase shifting interferometry and bipolar differential confocal microscopy to obtain high axis resolution, large dynamic range, and reduce the sensitivity to vibration and reflectance disturbance seamlessly. A compact single body spatial phase shifter is added to capture four phase-shifted interference signals simultaneously without time delay and construct a stable and space-saving simplified interference confocal microscope system. The test result can be obtained by combining the interference phase response and the bipolar property of differential confocal microscopy without phase unwrapping. Experiments prove that the proposed microscope is capable of providing stable measurements with 1 nm of axial depth resolution for either low- or high-numerical aperture objective lenses. PMID:27563909

  4. ERPs Differentially Reflect Automatic and Deliberate Processing of the Functional Manipulability of Objects

    PubMed Central

    Madan, Christopher R.; Chen, Yvonne Y.; Singhal, Anthony

    2016-01-01

    It is known that the functional properties of an object can interact with perceptual, cognitive, and motor processes. Previously we have found that a between-subjects manipulation of judgment instructions resulted in different manipulability-related memory biases in an incidental memory test. To better understand this effect we recorded electroencephalography (EEG) while participants made judgments about images of objects that were either high or low in functional manipulability (e.g., hammer vs. ladder). Using a between-subjects design, participants judged whether they had seen the object recently (Personal Experience), or could manipulate the object using their hand (Functionality). We focused on the P300 and slow-wave event-related potentials (ERPs) as reflections of attentional allocation. In both groups, we observed higher P300 and slow wave amplitudes for high-manipulability objects at electrodes Pz and C3. As P300 is thought to reflect bottom-up attentional processes, this may suggest that the processing of high-manipulability objects recruited more attentional resources. Additionally, the P300 effect was greater in the Functionality group. A more complex pattern was observed at electrode C3 during slow wave: processing the high-manipulability objects in the Functionality instruction evoked a more positive slow wave than in the other three conditions, likely related to motor simulation processes. These data provide neural evidence that effects of manipulability on stimulus processing are further mediated by automatic vs. deliberate motor-related processing. PMID:27536224

  5. About the contrast of δ' precipitates in bulk Al-Cu-Li alloys in reflection mode with a field-emission scanning electron microscope at low accelerating voltage.

    PubMed

    Brodusch, Nicolas; Voisard, Frédéric; Gauvin, Raynald

    2017-06-01

    Characterising the impact of lithium additions in the precipitation sequence in Al-Li-Cu alloys is important to control the strengthening of the final material. Since now, transmission electron microscopy (TEM) at high beam voltage has been the technique of choice to monitor the size and spatial distribution of δ' precipitates (Al3 Li). Here we report on the imaging of the δ' phase in such alloys using backscattered electrons (BSE) and low accelerating voltage in a high-resolution field-emission scanning electron microscope. By applying low-energy Ar(+) ion milling to the surface after mechanical polishing (MP), the MP-induced corroded layers were efficiently removed and permitted the δ's to be visible with a limited impact on the observed microstructure. The resulting BSE contrast between the δ's and the Al matrix was compared with that obtained using Monte Carlo modelling. The artefacts possibly resulting from the sample preparation procedure were reviewed and discussed and permitted to confirm that these precipitates were effectively the metastable δ's. The method described in this report necessitates less intensive sample preparation than that required for TEM and provides a much larger field of view and an easily interpretable contrast compared to the transmission techniques. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  6. Frontoparietal EEG alpha-phase synchrony reflects differential attentional demands during word recall and oculomotor dual-tasks.

    PubMed

    Kwon, Gusang; Kim, Min-Young; Lim, Sanghyun; Kwon, Hyukchan; Lee, Yong-Ho; Kim, Kiwoong; Lee, Eun-Ju; Suh, Minah

    2015-12-16

    To study the relationship between the varying degrees of cognitive load and long-range synchronization among neural networks, we utilized a dual-task paradigm combining concurrent word recall working memory tasks and oculomotor tasks that differentially activate the common frontoparietal (FP) network. We hypothesized that each dual-task combination would generate differential neuronal activation patterns among long-range connection during word retention period. Given that the FP alpha-phase synchronization is involved in attentional top-down processes, one would expect that the long-range synchronization pattern is affected by the degrees of dual-task demand. We measured a single-trial phase locking value in the alpha frequency (8-12 Hz) with electroencephalography in healthy participants. Single-trial phase locking value characterized the synchronization between two brain signals. Our results revealed that different amounts of FP alpha-phase synchronization were produced by different dual-task combinations, particularly during the early phase of the word retention period. These differences were dependent on the individual's working memory capacity and memory load. Our study shows that during dual-task, each oculomotor task, which is subserved by distinct neural network, generates different modulation patterns on long-range neuronal activation and FP alpha-phase synchronization seems to reflect these differential cognitive loads.

  7. Differential reactivity of brain microvascular endothelial cells to TNF reflects the genetic susceptibility to cerebral malaria.

    PubMed

    Lou, J; Gasche, Y; Zheng, L; Critico, B; Monso-Hinard, C; Juillard, P; Morel, P; Buurman, W A; Grau, G E

    1998-12-01

    Upon infection with Plasmodium berghei ANKA (PbA), various inbred strains of mice exhibit different susceptibility to the development of cerebral malaria (CM). Tumor necrosis factor-alpha (TNF) and interferon-gamma (IFN-gamma) have been shown to be crucial mediators in the pathogenesis of this neurovascular complication. Brain microvascular endothelial cells (MVEC) represent an important target of both cytokines. In the present study, we show that brain MVEC purified from CM-susceptible (CM-S) CBA/J mice and CM-resistant (CM-R) BALB/c mice exhibit a different sensitivity to TNF. CBA/J brain MVEC displayed a higher capacity to produce IL-6 and to up-regulate intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in response to TNF than BALB/c brain MVEC. In contrast, no difference was found in the induction of E-selectin after TNF challenge. CM-S brain MVEC were also significantly more sensitive to TNF-induced lysis. This differential reactivity to TNF was further substantiated by comparing TNF receptor expression on CM-S and CM-R brain MVEC. Although the constitutive expression of TNF receptors was comparable on cells from the two origins, TNF induced an up-regulation of both p55 and p75 TNF receptors in CM-S, but not in CM-R brain MVEC. A similar regulation was found at the level of TNF receptor mRNA, but not for receptor shedding. Although a protein kinase C inhibitor blocked the response to TNF in both the brain MVEC, an inhibitor of protein kinase A selectively abolished the response to TNF in CM-R, but not CM-S brain MVEC, suggesting a differential protein kinase involvement in TNF-induced activation of CM-S and CM-R brain MVEC. These results indicate that brain MVEC purified from CM-S and CM-R mice exhibit distinctive sensitivity to TNF This difference may be partly due to a differential regulation of TNF receptors and via distinct protein kinase pathways.

  8. Microscopic Polyangiitis

    PubMed Central

    Chung, Sharon A.; Seo, Philip

    2010-01-01

    Synopsis In 1923, Friedrich Wohlwill described two patients with a “microscopic form of periarteritis nodosa”, which was distinct from classical polyarteritis nodosa. This disease, now known as microscopic polyangiitis (MPA), is a primary systemic vasculitis characterized by inflammation of the small-caliber blood vessels and the presence of circulating antineutrophil cytoplasmic antibodies (ANCA). Typically, microscopic polyangiitis presents with glomerulonephritis and pulmonary capillaritis, although involvement of the skin, nerves, and gastrointestinal tract is not uncommon. Treatment of MPA generally requires use of a cytotoxic agent (such as cyclophosphamide) in addition to high-dose glucocorticoids. Recent research has focused on identifying alternate treatment strategies that minimize or eliminate exposure to cytotoxic agents. This article will review the history, pathogenesis, clinical manifestations, and treatment of MPA. PMID:20688249

  9. Martian Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The microscopic imager (circular device in center) is in clear view above the surface at Meridiani Planum, Mars, in this approximate true-color image taken by the panoramic camera on the Mars Exploration Rover Opportunity. The image was taken on the 9th sol of the rover's journey. The microscopic imager is located on the rover's instrument deployment device, or arm. The arrow is pointing to the lens of the instrument. Note the dust cover, which flips out to the left of the lens, is open. This approximated color image was created using the camera's violet and infrared filters as blue and red.

  10. Martian Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The microscopic imager (circular device in center) is in clear view above the surface at Meridiani Planum, Mars, in this approximate true-color image taken by the panoramic camera on the Mars Exploration Rover Opportunity. The image was taken on the 9th sol of the rover's journey. The microscopic imager is located on the rover's instrument deployment device, or arm. The arrow is pointing to the lens of the instrument. Note the dust cover, which flips out to the left of the lens, is open. This approximated color image was created using the camera's violet and infrared filters as blue and red.

  11. Digital FDIRC: A focused differential internal reflection Cherenkov imaged by SiPM arrays

    NASA Astrophysics Data System (ADS)

    Marrocchesi, P. S.; Bagliesi, M. G.; Basti, A.; Bigongiari, G.; Bonechi, S.; Brogi, P.; Checchia, C.; Collazuol, G.; Maestro, P.; Morsani, F.; Piemonte, C.; Stolzi, F.; Suh, J. E.; Sulaj, A.

    2016-07-01

    A prototype of an Internal Reflection Cherenkov, equipped with a SiO2 (fused silica) radiator bar optically connected to a cylindrical mirror, was tested at CERN SPS in March 2015 with a beam of relativistic ions obtained from fragmentation of primary argon nuclei at energies 13, 19 and 30 GeV/n. The detector, designed to identify cosmic nuclei, features an imaging focal plane of dimensions 4 cm × 3 cm equipped with 16 arrays of NUV-SiPM (near-ultraviolet sensitive silicon photon avalanche detector) for a total of 1024 sensitive elements. The outstanding performance of the photodetectors (with negligible background in between adjacent photopeaks) allowed us to apply the technique of photon counting to the Cherenkov light collected on the focal plane. Thanks to the fine granularity of the array elements, the Cherenkov pattern was recorded together with the total number of detected photoelectrons increasing as Z2 as a function of the atomic number Z. In this paper, we report the performance of the SiPM arrays and the excellent resolution achieved by the digital Cherenkov prototype in the charge identification of the elements present in the beam.

  12. Differential investment in visual and olfactory brain areas reflects behavioural choices in hawk moths

    PubMed Central

    Stöckl, Anna; Heinze, Stanley; Charalabidis, Alice; el Jundi, Basil; Warrant, Eric; Kelber, Almut

    2016-01-01

    Nervous tissue is one of the most metabolically expensive animal tissues, thus evolutionary investments that result in enlarged brain regions should also result in improved behavioural performance. Indeed, large-scale comparative studies in vertebrates and invertebrates have successfully linked differences in brain anatomy to differences in ecology and behaviour, but their precision can be limited by the detail of the anatomical measurements, or by only measuring behaviour indirectly. Therefore, detailed case studies are valuable complements to these investigations, and have provided important evidence linking brain structure to function in a range of higher-order behavioural traits, such as foraging experience or aggressive behaviour. Here, we show that differences in the size of both lower and higher-order sensory brain areas reflect differences in the relative importance of these senses in the foraging choices of hawk moths, as suggested by previous anatomical work in Lepidopterans. To this end we combined anatomical and behavioural quantifications of the relative importance of vision and olfaction in two closely related hawk moth species. We conclude that differences in sensory brain volume in these hawk moths can indeed be interpreted as differences in the importance of these senses for the animal’s behaviour. PMID:27185464

  13. Brain tumour differentiation: rapid stratified serum diagnostics via attenuated total reflection Fourier-transform infrared spectroscopy.

    PubMed

    Hands, James R; Clemens, Graeme; Stables, Ryan; Ashton, Katherine; Brodbelt, Andrew; Davis, Charles; Dawson, Timothy P; Jenkinson, Michael D; Lea, Robert W; Walker, Carol; Baker, Matthew J

    2016-05-01

    The ability to diagnose cancer rapidly with high sensitivity and specificity is essential to exploit advances in new treatments to lead significant reductions in mortality and morbidity. Current cancer diagnostic tests observing tissue architecture and specific protein expression for specific cancers suffer from inter-observer variability, poor detection rates and occur when the patient is symptomatic. A new method for the detection of cancer using 1 μl of human serum, attenuated total reflection-Fourier transform infrared spectroscopy and pattern recognition algorithms is reported using a 433 patient dataset (3897 spectra). To the best of our knowledge, we present the largest study on serum mid-infrared spectroscopy for cancer research. We achieve optimum sensitivities and specificities using a Radial Basis Function Support Vector Machine of between 80.0 and 100 % for all strata and identify the major spectral features, hence biochemical components, responsible for the discrimination within each stratum. We assess feature fed-SVM analysis for our cancer versus non-cancer model and achieve 91.5 and 83.0 % sensitivity and specificity respectively. We demonstrate the use of infrared light to provide a spectral signature from human serum to detect, for the first time, cancer versus non-cancer, metastatic cancer versus organ confined, brain cancer severity and the organ of origin of metastatic disease from the same sample enabling stratified diagnostics depending upon the clinical question asked.

  14. Differential methylation between ethnic sub-groups reflects the effect of genetic ancestry and environmental exposures

    PubMed Central

    Galanter, Joshua M; Gignoux, Christopher R; Oh, Sam S; Torgerson, Dara; Pino-Yanes, Maria; Thakur, Neeta; Eng, Celeste; Hu, Donglei; Huntsman, Scott; Farber, Harold J; Avila, Pedro C; Brigino-Buenaventura, Emerita; LeNoir, Michael A; Meade, Kelly; Serebrisky, Denise; Rodríguez-Cintrón, William; Kumar, Rajesh; Rodríguez-Santana, Jose R; Seibold, Max A; Borrell, Luisa N; Burchard, Esteban G; Zaitlen, Noah

    2017-01-01

    Populations are often divided categorically into distinct racial/ethnic groups based on social rather than biological constructs. Genetic ancestry has been suggested as an alternative to this categorization. Herein, we typed over 450,000 CpG sites in whole blood of 573 individuals of diverse Hispanic origin who also had high-density genotype data. We found that both self-identified ethnicity and genetically determined ancestry were each significantly associated with methylation levels at 916 and 194 CpGs, respectively, and that shared genomic ancestry accounted for a median of 75.7% (IQR 45.8% to 92%) of the variance in methylation associated with ethnicity. There was a significant enrichment (p=4.2×10-64) of ethnicity-associated sites amongst loci previously associated environmental exposures, particularly maternal smoking during pregnancy. We conclude that differential methylation between ethnic groups is partially explained by the shared genetic ancestry but that environmental factors not captured by ancestry significantly contribute to variation in methylation. DOI: http://dx.doi.org/10.7554/eLife.20532.001 PMID:28044981

  15. Differential methylation between ethnic sub-groups reflects the effect of genetic ancestry and environmental exposures.

    PubMed

    Galanter, Joshua M; Gignoux, Christopher R; Oh, Sam S; Torgerson, Dara; Pino-Yanes, Maria; Thakur, Neeta; Eng, Celeste; Hu, Donglei; Huntsman, Scott; Farber, Harold J; Avila, Pedro C; Brigino-Buenaventura, Emerita; LeNoir, Michael A; Meade, Kelly; Serebrisky, Denise; Rodríguez-Cintrón, William; Kumar, Rajesh; Rodríguez-Santana, Jose R; Seibold, Max A; Borrell, Luisa N; Burchard, Esteban G; Zaitlen, Noah

    2017-01-03

    Populations are often divided categorically into distinct racial/ethnic groups based on social rather than biological constructs. Genetic ancestry has been suggested as an alternative to this categorization. Herein, we typed over 450,000 CpG sites in whole blood of 573 individuals of diverse Hispanic origin who also had high-density genotype data. We found that both self-identified ethnicity and genetically determined ancestry were each significantly associated with methylation levels at 916 and 194 CpGs, respectively, and that shared genomic ancestry accounted for a median of 75.7% (IQR 45.8% to 92%) of the variance in methylation associated with ethnicity. There was a significant enrichment (p=4.2×10(-64)) of ethnicity-associated sites amongst loci previously associated environmental exposures, particularly maternal smoking during pregnancy. We conclude that differential methylation between ethnic groups is partially explained by the shared genetic ancestry but that environmental factors not captured by ancestry significantly contribute to variation in methylation.

  16. Microscopic colitis.

    PubMed

    Delgado, Jorge; Delgado, Bertha; Fich, Alex; Odes, Shmuel

    2004-08-01

    Microscopic colitis is an idiopathic chronic inflammatory bowel disease presenting with watery diarrhea. While colonoscopy and radiology findings are normal, the colon shows striking pathologic findings, including lymphocytic colitis and collagenous colitis. The clinical course is usually benign with sustained remission. Recent medical evidence shows that bismuth and budesonide are effective treatments.

  17. Microscopic colitis

    PubMed Central

    Ianiro, Gianluca; Cammarota, Giovanni; Valerio, Luca; Annicchiarico, Brigida Eleonora; Milani, Alessandro; Siciliano, Massimo; Gasbarrini, Antonio

    2012-01-01

    Microscopic colitis may be defined as a clinical syndrome, of unknown etiology, consisting of chronic watery diarrhea, with no alterations in the large bowel at the endoscopic and radiologic evaluation. Therefore, a definitive diagnosis is only possible by histological analysis. The epidemiological impact of this disease has become increasingly clear in the last years, with most data coming from Western countries. Microscopic colitis includes two histological subtypes [collagenous colitis (CC) and lymphocytic colitis (LC)] with no differences in clinical presentation and management. Collagenous colitis is characterized by a thickening of the subepithelial collagen layer that is absent in LC. The main feature of LC is an increase of the density of intra-epithelial lymphocytes in the surface epithelium. A number of pathogenetic theories have been proposed over the years, involving the role of luminal agents, autoimmunity, eosinophils, genetics (human leukocyte antigen), biliary acids, infections, alterations of pericryptal fibroblasts, and drug intake; drugs like ticlopidine, carbamazepine or ranitidine are especially associated with the development of LC, while CC is more frequently linked to cimetidine, non-steroidal antiinflammatory drugs and lansoprazole. Microscopic colitis typically presents as chronic or intermittent watery diarrhea, that may be accompanied by symptoms such as abdominal pain, weight loss and incontinence. Recent evidence has added new pharmacological options for the treatment of microscopic colitis: the role of steroidal therapy, especially oral budesonide, has gained relevance, as well as immunosuppressive agents such as azathioprine and 6-mercaptopurine. The use of anti-tumor necrosis factor-α agents, infliximab and adalimumab, constitutes a new, interesting tool for the treatment of microscopic colitis, but larger, adequately designed studies are needed to confirm existing data. PMID:23180940

  18. Microscopic colitis.

    PubMed

    Ianiro, Gianluca; Cammarota, Giovanni; Valerio, Luca; Annicchiarico, Brigida Eleonora; Milani, Alessandro; Siciliano, Massimo; Gasbarrini, Antonio

    2012-11-21

    Microscopic colitis may be defined as a clinical syndrome, of unknown etiology, consisting of chronic watery diarrhea, with no alterations in the large bowel at the endoscopic and radiologic evaluation. Therefore, a definitive diagnosis is only possible by histological analysis. The epidemiological impact of this disease has become increasingly clear in the last years, with most data coming from Western countries. Microscopic colitis includes two histological subtypes [collagenous colitis (CC) and lymphocytic colitis (LC)] with no differences in clinical presentation and management. Collagenous colitis is characterized by a thickening of the subepithelial collagen layer that is absent in LC. The main feature of LC is an increase of the density of intra-epithelial lymphocytes in the surface epithelium. A number of pathogenetic theories have been proposed over the years, involving the role of luminal agents, autoimmunity, eosinophils, genetics (human leukocyte antigen), biliary acids, infections, alterations of pericryptal fibroblasts, and drug intake; drugs like ticlopidine, carbamazepine or ranitidine are especially associated with the development of LC, while CC is more frequently linked to cimetidine, non-steroidal antiinflammatory drugs and lansoprazole. Microscopic colitis typically presents as chronic or intermittent watery diarrhea, that may be accompanied by symptoms such as abdominal pain, weight loss and incontinence. Recent evidence has added new pharmacological options for the treatment of microscopic colitis: the role of steroidal therapy, especially oral budesonide, has gained relevance, as well as immunosuppressive agents such as azathioprine and 6-mercaptopurine. The use of anti-tumor necrosis factor-α agents, infliximab and adalimumab, constitutes a new, interesting tool for the treatment of microscopic colitis, but larger, adequately designed studies are needed to confirm existing data.

  19. Differential Gene Expression Profiles Reflecting Macrophage Polarization in Aging and Periodontitis Gingival Tissues.

    PubMed

    Gonzalez, O A; Novak, M J; Kirakodu, S; Stromberg, A; Nagarajan, R; Huang, C B; Chen, K C; Orraca, L; Martinez-Gonzalez, J; Ebersole, J L

    2015-01-01

    Recent evidence has determined a phenotypic and functional heterogeneity for macrophage populations. This plasticity of macrophage function has been related to specific properties of subsets (M1 and M2) of these cells in inflammation, adaptive immune responses and resolution of tissue destructive processes. This investigation hypothesized that targeted alterations in the distribution of macrophage phenotypes in aged individuals, and with periodontitis would be skewed towards M1 inflammatory macrophages in gingival tissues. The study used a non-human primate model to evaluate gene expression profiles as footprints of macrophage variation in healthy and periodontitis gingival tissues from animals 3-23 years of age and in periodontitis tissues in adult and aged animals. Significant increases in multiple genes reflecting overall increases in macrophage activities were observed in healthy aged tissues, and were significantly increased in periodontitis tissues from both adults and aged animals. Generally, gene expression patterns for M2 macrophages were similar in healthy young, adolescent and adult tissues. However, modest increases were noted in healthy aged tissues, similar to those seen in periodontitis tissues from both age groups. M1 macrophage gene transcription patterns increased significantly over the age range in healthy tissues, with multiple genes (e.g. CCL13, CCL19, CCR7 and TLR4) significantly increased in aged animals. Additionally, gene expression patterns for M1 macrophages were significantly increased in adult health versus periodontitis and aged healthy versus periodontitis. The findings supported a significant increase in macrophages with aging and in periodontitis. The primary increases in both healthy aged tissues and, particularly periodontitis tissues appeared in the M1 phenotype.

  20. Differential Gene Expression Profiles Reflecting Macrophage Polarization in Aging and Periodontitis Gingival Tissues

    PubMed Central

    Gonzalez, O.A.; Novak, M.J.; Kirakodu, S.; Stromberg, A.; Nagarajan, R.; Huang, C.B.; Chen, K.C.; Orraca, L.; Martinez-Gonzalez, J.; Ebersole, J.L.

    2016-01-01

    SUMMARY Recent evidence has determined a phenotypic and functional heterogeneity for macrophage populations. This plasticity of macrophage function has been related to specific properties of subsets (M1, M2) of these cells in inflammation, adaptive immune responses, and resolution of tissue destructive processes. This investigation hypothesized that targeted alterations in the distribution of macrophage phenotypes in aged individuals, and with periodontitis would be skewed towards M1 inflammatory macrophages in gingival tissues. The study used a nonhuman primate model to evaluate gene expression profiles as footprints of macrophage variation in healthy and periodontitis gingival tissues from animals 3–23 years of age and in periodontitis tissues in adult and aged animals. Significant increases in multiple genes reflecting overall increases in macrophage activities were observed in healthy aged tissues, and were significantly increased in periodontitis tissues from both adults and aged animals. Generally, gene expression patterns for M2 macrophages were similar in healthy young, adolescent, and adult tissues. However, modest increases were noted in healthy aged tissues, similar to those seen in periodontitis tissues from both age groups. M1 macrophage gene transcription patterns increased significantly over the age range in healthy tissues, with multiple genes (e.g. CCL13, CCL19, CCR7, TLR4) significantly increased in aged animals. Additionally, gene expression patterns for M1 macrophages were significantly increased in adult health versus periodontitis and aged healthy versus periodontitis. The findings supported a significant increase in macrophages with aging and in periodontitis. The primary increases in both healthy aged tissues and, particularly periodontitis tissues appeared in the M1 phenotype. PMID:26397131

  1. Interprofessional collaboration - a matter of differentiation and integration? Theoretical reflections based in the context of Norwegian childcare.

    PubMed

    Willumsen, Elisabeth

    2008-08-01

    This paper presents a selection of theoretical approaches illuminating some aspects of interprofessional collaboration, which will be related to theory of contingency as well as to the concepts of differentiation and integration. Theories that describe collaboration on an interpersonal as well as inter-organizational level are outlined and related to dynamic and contextual factors. Implications for the organization of welfare services are elucidated and a categorization of internal and external collaborative forms is proposed. A reflection model is presented in order to analyse the degree of integration in collaborative work and may serve as an analytical tool for addressing the linkage between different levels of collaboration and identifying opportunities and limitations. Some implications related to the legal mandate(s) given to childcare agencies are discussed in relation to the context of childcare in Norway.

  2. Measurement and calculation of the differential reflectance spectrum of hydrogen-terminated silicon surfaces having different crystal orientations.

    PubMed

    Inagaki, K; Okada, N; Noda, T; Endo, K; Hirose, K

    2007-09-12

    The differential reflectance spectrum between the (001) and the (111) hydrogen-terminated Si surfaces without native oxidation is investigated. Careful measurements using developed apparatus and an ultra-clean process are performed. The measured spectrum is compared with the reported one (Chongsawangvirod and Irene 1991 J. Electrochem. Soc. 138 1748-52), and is shown to be roughly identical even though a native oxidation effect exists. The theoretical calculation based on density-functional theory (DFT) and local density approximation (LDA) is also performed. The peak positions in the calculated and the measured spectra are in good accordance with each other, while the magnitudes of the peaks are in relatively worse agreement. Although the inclusion of advanced approximations would provide more accurate results, a qualitative reproduction is achieved in this study as well. It is concluded that the origin of the spectrum is mainly in the deformation of the bulk states induced by surface perturbation.

  3. Collaborative Reflection Under the Microscope: Using Conversation Analysis to Study the Transition From Case Presentation to Discussion in GP Residents' Experience Sharing Sessions.

    PubMed

    Veen, Mario; de la Croix, Anne

    2016-01-01

    PHENOMENON: In higher education, reflection sessions are often used when participants learn in the workplace. In the Netherlands, all General Practitioner training programs include regular meetings called Exchange of Experiences, in which General Practitioner trainees are expected to learn collaboratively from their own and one another's experiences. Despite this being common practice, we found little research into the structure and process of these sessions. The purpose of this study is to describe the structure and characteristics of group reflection by describing transitions in interactions. We aim to describe the tutor's role in some detail, as this could lead to faculty development. In medical education, reflection is often approached from a cognitive perspective. However, learning in a group is also an interactional achievement. It is therefore relevant to study the sequential nature of group interaction in collaborative reflective practice. We have used conversation analysis to study the reflection meetings, zooming in on the transition between case presentation and discussion, focusing on the role of each of the participants in these transitions. The transitions were conversationally complex. Three interactional aspects recurred in the meetings. First, the transitions can be characterized as ambiguous, as there is ambiguity about what will happen next and the floor is open. Second, transitions are an arena for negotiations between case presenter, participants, and tutors, in which knowledge and the right to take the floor (epistemics) play an important part. Third, the tutor can have different interactional roles, namely, that of teacher, expert, facilitator, and active participant. The role of the tutor is important as the tutor's interactional behavior is part of the hidden curriculum. Insights: Conversation analysis focuses on the interaction in group learning and shows how the interaction is part of what is learned and how learning takes place

  4. Low frequency acoustic microscope

    DOEpatents

    Khuri-Yakub, Butrus T.

    1986-11-04

    A scanning acoustic microscope is disclosed for the detection and location of near surface flaws, inclusions or voids in a solid sample material. A focused beam of acoustic energy is directed at the sample with its focal plane at the subsurface flaw, inclusion or void location. The sample is scanned with the beam. Detected acoustic energy specularly reflected and mode converted at the surface of the sample and acoustic energy reflected by subsurface flaws, inclusions or voids at the focal plane are used for generating an interference signal which is processed and forms a signal indicative of the subsurface flaws, inclusions or voids.

  5. Terahertz Microscope

    DTIC Science & Technology

    2010-05-01

    bases and bacterial spores , etc. Recently, biomolecular nanoparticles have been successfully imaged using a THz microscope by the group of Prof. Han...compounds, pharmaceutical materials, illegal drugs, amino acids, nuclei-bases and 30 bacterial spores , etc. THz waves can also penetrate through many...Am. B, vol. 7, pp. 2006-2015, 1990. 25. J. D. Joannopoulos, R. D. Meade, and J. N. Winn, Photonic Crystals: Molding the Flow of Light, Princeton U

  6. Correction of terrestrial LiDAR intensity channel using Oren-Nayar reflectance model: An application to lithological differentiation

    NASA Astrophysics Data System (ADS)

    Carrea, Dario; Abellan, Antonio; Humair, Florian; Matasci, Battista; Derron, Marc-Henri; Jaboyedoff, Michel

    2016-03-01

    Ground-based LiDAR has been traditionally used for surveying purposes via 3D point clouds. In addition to XYZ coordinates, an intensity value is also recorded by LiDAR devices. The intensity of the backscattered signal can be a significant source of information for various applications in geosciences. Previous attempts to account for the scattering of the laser signal are usually modelled using a perfect diffuse reflection. Nevertheless, experience on natural outcrops shows that rock surfaces do not behave as perfect diffuse reflectors. The geometry (or relief) of the scanned surfaces plays a major role in the recorded intensity values. Our study proposes a new terrestrial LiDAR intensity correction, which takes into consideration the range, the incidence angle and the geometry of the scanned surfaces. The proposed correction equation combines the classical radar equation for LiDAR with the bidirectional reflectance distribution function of the Oren-Nayar model. It is based on the idea that the surface geometry can be modelled by a relief of multiple micro-facets. This model is constrained by only one tuning parameter: the standard deviation of the slope angle distribution (σslope) of micro-facets. Firstly, a series of tests have been carried out in laboratory conditions on a 2 m2 board covered by black/white matte paper (perfect diffuse reflector) and scanned at different ranges and incidence angles. Secondly, other tests were carried out on rock blocks of different lithologies and surface conditions. Those tests demonstrated that the non-perfect diffuse reflectance of rock surfaces can be practically handled by the proposed correction method. Finally, the intensity correction method was applied to a real case study, with two scans of the carbonate rock outcrop of the Dents-du-Midi (Swiss Alps), to improve the lithological identification for geological mapping purposes. After correction, the intensity values are proportional to the intrinsic material reflectance

  7. Effect of polyglycerol esters additive on palm oil crystallization using focused beam reflectance measurement and differential scanning calorimetry.

    PubMed

    Saw, M H; Hishamuddin, E; Chong, C L; Yeoh, C B; Lim, W H

    2017-01-01

    The effect of 0.1-0.7% (w/w) of polyglycerol esters (PGEmix-8) on palm oil crystallization was studied using focused beam reflectance measurement (FBRM) to analyze the in-line changes of crystal size distribution during the crystallization. FBRM results show that 0.1-0.5% (w/w) of PGEmix-8 did not significantly affect nucleation but slightly retarded crystal growth. The use of 0.7% (w/w) additive showed greater heterogeneous nucleation compared to those with lower dosages of additive. Crystal growth was also greatly reduced when using 0.7% (w/w) dosage. The morphological study indicated that the palm oil crystals were smaller and more even in size than when more additive was added. Isothermal crystallization studies using differential scanning calorimetry (DSC) showed increased inhibitory effects on palm oil crystal growth with increasing concentration of PGEmix-8. These results imply that PGEmix-8 is a nucleation enhancing and crystal growth retarding additive in palm oil crystallization at 0.7% (w/w) dosage.

  8. Acoustic imaging microscope

    DOEpatents

    Deason, Vance A.; Telschow, Kenneth L.

    2006-10-17

    An imaging system includes: an object wavefront source and an optical microscope objective all positioned to direct an object wavefront onto an area of a vibrating subject surface encompassed by a field of view of the microscope objective, and to direct a modulated object wavefront reflected from the encompassed surface area through a photorefractive material; and a reference wavefront source and at least one phase modulator all positioned to direct a reference wavefront through the phase modulator and to direct a modulated reference wavefront from the phase modulator through the photorefractive material to interfere with the modulated object wavefront. The photorefractive material has a composition and a position such that interference of the modulated object wavefront and modulated reference wavefront occurs within the photorefractive material, providing a full-field, real-time image signal of the encompassed surface area.

  9. Molecular and iridescent feather reflectance data reveal recent genetic diversification and phenotypic differentiation in a cloud forest hummingbird.

    PubMed

    Ornelas, Juan Francisco; González, Clementina; Hernández-Baños, Blanca E; García-Moreno, Jaime

    2016-02-01

    The present day distribution and spatial genetic diversity of Mesoamerican biota reflects a long history of responses to habitat change. The hummingbird Lampornis amethystinus is distributed in northern Mesoamerica, with geographically disjunct populations. Based on sampling across the species range using mitochondrial DNA (mtDNA) sequences and nuclear microsatellites jointly analysed with phenotypic and climatic data, we (1) test whether the fragmented distribution is correlated with main evolutionary lineages, (2) assess body size and plumage color differentiation of populations in geographic isolation, and (3) evaluate a set of divergence scenarios and demographic patterns of the hummingbird populations. Analysis of genetic variation revealed four main groups: blue-throated populations (Sierra Madre del Sur); two groups of amethyst-throated populations (Trans-Mexican Volcanic Belt and Sierra Madre Oriental); and populations east of the Isthmus of Tehuantepec (IT) with males showing an amethyst throat. The most basal split is estimated to have originated in the Pleistocene, 2.39-0.57 million years ago (MYA), and corresponded to groups of populations separated by the IT. However, the estimated recent divergence time between blue- and amethyst-throated populations does not correspond to the 2-MY needed to be in isolation for substantial plumage divergence, likely because structurally iridescent colors are more malleable than others. Results of species distribution modeling and Approximate Bayesian Computation analysis fit a model of lineage divergence west of the Isthmus after the Last Glacial Maximum (LGM), and that the species' suitable habitat was disjunct during past and current conditions. These results challenge the generality of the contraction/expansion glacial model to cloud forest-interior species and urges management of cloud forest, a highly vulnerable ecosystem to climate change and currently facing destruction, to prevent further loss of genetic

  10. Virtual pinhole confocal microscope

    SciTech Connect

    George, J.S.; Rector, D.M.; Ranken, D.M.; Peterson, B.; Kesteron, J.

    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.

  11. Scanning Miniature Microscopes without Lenses

    NASA Technical Reports Server (NTRS)

    Wang, Yu

    2009-01-01

    The figure schematically depicts some alternative designs of proposed compact, lightweight optoelectronic microscopes that would contain no lenses and would generate magnified video images of specimens. Microscopes of this type were described previously in Miniature Microscope Without Lenses (NPO - 20218), NASA Tech Briefs, Vol. 22, No. 8 (August 1998), page 43 and Reflective Variants of Miniature Microscope Without Lenses (NPO 20610), NASA Tech Briefs, Vol. 26, No. 9 (September 1999), page 6a. To recapitulate: In the design and construction of a microscope of this type, the focusing optics of a conventional microscope are replaced by a combination of a microchannel filter and a charge-coupled-device (CCD) image detector. Elimination of focusing optics reduces the size and weight of the instrument and eliminates the need for the time-consuming focusing operation. The microscopes described in the cited prior articles contained two-dimensional CCDs registered with two-dimensional arrays of microchannels and, as such, were designed to produce full two-dimensional images, without need for scanning. The microscopes of the present proposal would contain one-dimensional (line image) CCDs registered with linear arrays of microchannels. In the operation of such a microscope, one would scan a specimen along a line perpendicular to the array axis (in other words, one would scan in pushbroom fashion). One could then synthesize a full two-dimensional image of the specimen from the line-image data acquired at one-pixel increments of position along the scan. In one of the proposed microscopes, a beam of unpolarized light for illuminating the specimen would enter from the side. This light would be reflected down onto the specimen by a nonpolarizing beam splitter attached to the microchannels at their lower ends. A portion of the light incident on the specimen would be reflected upward, through the beam splitter and along the microchannels, to form an image on the CCD. If the

  12. Color Laser Microscope

    NASA Astrophysics Data System (ADS)

    Awamura, D.; Ode, T.; Yonezawa, M.

    1987-04-01

    A color laser microscope utilizing a new color laser imaging system has been developed for the visual inspection of semiconductors. The light source, produced by three lasers (Red; He-Ne, Green; Ar, Blue; He-Cd), is deflected horizontally by an AOD (Acoustic Optical Deflector) and vertically by a vibration mirror. The laser beam is focused in a small spot which is scanned over the sample at high speed. The light reflected back from the sample is reformed to contain linear information by returning to the original vibration mirror. The linear light is guided to the CCD image sensor where it is converted into a video signal. Individual CCD image sensors are used for each of the three R, G, or B color image signals. The confocal optical system with its laser light source yields a color TV monitor image with no flaring and a much sharper resolution than that of the conventional optical microscope. The AOD makes possible a high speed laser scan and a NTSC or PAL TV video signal is produced in real time without any video memory. Since the light source is composed of R, G, and B laser beams, color separation superior to that of white light illumination is achieved. Because of the photometric linearity of the image detector, the R, G, and B outputs of the system are most suitably used for hue analysis. The CCD linear image sensors in the optical system produce no geometrical distortion, and good color registration is available principally. The output signal can be used for high accuracy line width measuring. The many features of the color laser microscope make it ideally suited for the visual inspection of semiconductor processing. A number of these systems have already been installed in such a capacity. The Color Laser Microscope can also be a very useful tool for the fields of material engineering and biotechnology.

  13. Microscopic derivation of discrete hydrodynamics.

    PubMed

    Español, Pep; Anero, Jesús G; Zúñiga, Ignacio

    2009-12-28

    By using the standard theory of coarse graining based on Zwanzig's projection operator, we derive the dynamic equations for discrete hydrodynamic variables. These hydrodynamic variables are defined in terms of the Delaunay triangulation. The resulting microscopically derived equations can be understood, a posteriori, as a discretization on an arbitrary irregular grid of the Navier-Stokes equations. The microscopic derivation provides a set of discrete equations that exactly conserves mass, momentum, and energy and the dissipative part of the dynamics produces strict entropy increase. In addition, the microscopic derivation provides a practical implementation of thermal fluctuations in a way that the fluctuation-dissipation theorem is satisfied exactly. This paper points toward a close connection between coarse-graining procedures from microscopic dynamics and discretization schemes for partial differential equations.

  14. An entanglement-enhanced microscope.

    PubMed

    Ono, Takafumi; Okamoto, Ryo; Takeuchi, Shigeki

    2013-01-01

    Among the applications of optical phase measurement, the differential interference contrast microscope is widely used for the evaluation of opaque materials or biological tissues. However, the signal-to-noise ratio for a given light intensity is limited by the standard quantum limit, which is critical for measurements where the probe light intensity is limited to avoid damaging the sample. The standard quantum limit can only be beaten by using N quantum correlated particles, with an improvement factor of √N. Here we report the demonstration of an entanglement-enhanced microscope, which is a confocal-type differential interference contrast microscope where an entangled photon pair (N=2) source is used for illumination. An image of a Q shape carved in relief on the glass surface is obtained with better visibility than with a classical light source. The signal-to-noise ratio is 1.35±0.12 times better than that limited by the standard quantum limit.

  15. Attachment converts microscope to point source autocollimator

    NASA Technical Reports Server (NTRS)

    Shlichta, P. J.

    1964-01-01

    A low-power microscope or telescope provides a simple means of autocollimation. This is done by fitting the instrument with a light source to permit alignment from a reflecting surface normal to the optic axis of the instrument.

  16. The hydrogen molecule under the reaction microscope: single photon double ionization at maximum cross section and threshold (doubly differential cross sections)

    NASA Astrophysics Data System (ADS)

    Weber, Thorsten; Foucar, Lutz; Jahnke, Till; Schoeffler, Markus; Schmidt, Lothar; Prior, Michael; Doerner, Reinhard

    2017-08-01

    We studied the photo double ionization of hydrogen molecules in the threshold region (50 eV) and the complete photo fragmentation of deuterium molecules at maximum cross section (75 eV) with single photons (linearly polarized) from the Advanced Light Source, using the reaction microscope imaging technique. The 3D-momentum vectors of two recoiling ions and up to two electrons were measured in coincidence. We present the kinetic energy sharing between the electrons and ions, the relative electron momenta, the azimuthal and polar angular distributions of the electrons in the body-fixed frame. We also present the dependency of the kinetic energy release in the Coulomb explosion of the two nuclei on the electron emission patterns. We find that the electronic emission in the body-fixed frame is strongly influenced by the orientation of the molecular axis to the polarization vector and the internuclear distance as well as the electronic energy sharing. Traces of a possible breakdown of the Born-Oppenheimer approximation are observed near threshold.

  17. Forensic Scanning Electron Microscope

    NASA Astrophysics Data System (ADS)

    Keeley, R. H.

    1983-03-01

    The scanning electron microscope equipped with an x-ray spectrometer is a versatile instrument which has many uses in the investigation of crime and preparation of scientific evidence for the courts. Major applications include microscopy and analysis of very small fragments of paint, glass and other materials which may link an individual with a scene of crime, identification of firearms residues and examination of questioned documents. Although simultaneous observation and chemical analysis of the sample is the most important feature of the instrument, other modes of operation such as cathodoluminescence spectrometry, backscattered electron imaging and direct x-ray excitation are also exploited. Marks on two bullets or cartridge cases can be compared directly by sequential scanning with a single beam or electronic linkage of two instruments. Particles of primer residue deposited on the skin and clothing when a gun is fired can be collected on adhesive tape and identified by their morphology and elemental composition. It is also possible to differentiate between the primer residues of different types of ammunition. Bullets may be identified from the small fragments left behind as they pass through the body tissues. In the examination of questioned documents the scanning electron microscope is used to establish the order in which two intersecting ink lines were written and to detect traces of chemical markers added to the security inks on official documents.

  18. Miscibility, Crystallization, and Rheological Behavior of Solution Casting Poly(3-hydroxybutyrate)/poly(ethylene succinate) Blends Probed by Differential Scanning Calorimetry, Rheology, and Optical Microscope Techniques

    NASA Astrophysics Data System (ADS)

    Sun, Wei-hua; Qiao, Xiao-ping; Cao, Qi-kun; Liu, Jie-ping

    2010-02-01

    The miscibility and crystallization of solution casting biodegradable poly(3-hydroxybutyrate)/poly(ethylene succinate) (PHB/PES) blends was investigated by differential scanning calorimetry, rheology, and optical microscopy. The blends showed two glass transition temperatures and a depression of melting temperature of PHB with compositions in phase diagram, which indicated that the blend was partially miscible. The morphology observation supported this result. It was found that the PHB and PES can crystallize simultaneously or upon stepwise depending on the crystallization temperatures and compositions. The spherulite growth rate of PHB increased with increasing of PES content. The influence of compositions on the spherulitic growth rate for the partially miscible polymer blends was discussed.

  19. Embryos, microscopes, and society.

    PubMed

    Maienschein, Jane

    2016-06-01

    Embryos have different meanings for different people and in different contexts. Seen under the microscope, the biological embryo starts out as one cell and then becomes a bunch of cells. Gradually these divide and differentiate to make up the embryo, which in humans becomes a fetus at eight weeks, and then eventually a baby. At least, that happens in those cases that carry through normally and successfully. Yet a popular public perception imagines the embryo as already a little person in the very earliest stages of development, as if it were predictably to become an adult. In actuality, cells can combine, pull apart, and recombine in a variety of ways and still produce embryos, whereas most embryos never develop into adults at all. Biological embryos and popular imaginations of embryos diverge. This paper looks at some of the historical reasons for and social implications of that divergence.

  20. Imaging Schwarzschild multilayer X-ray microscope

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.; Baker, Phillip C.; Shealy, David L.; Core, David B.; Walker, Arthur B. C., Jr.; Barbee, Troy W., Jr.; Kerstetter, Ted

    1993-01-01

    We have designed, analyzed, fabricated, and tested Schwarzschild multilayer X-ray microscopes. These instruments use flow-polished Zerodur mirror substrates which have been coated with multilayers optimized for maximum reflectivity at normal incidence at 135 A. They are being developed as prototypes for the Water Window Imaging X-Ray Microscope. Ultrasmooth mirror sets of hemlite grade sapphire have been fabricated and they are now being coated with multilayers to reflect soft X-rays at 38 A, within the biologically important 'water window'. In this paper, we discuss the fabrication of the microscope optics and structural components as well as the mounting of the optics and assembly of the microscopes. We also describe the optical alignment, interferometric and visible light testing of the microscopes, present interferometrically measured performance data, and provide the first results of optical imaging tests.

  1. Huygens-Fresnel Wave-Optics Simulation of Atmosphere Optical Turbulence and Reflective Speckle in CO{sub 2} Differential Absorption Lidar (DIAL)

    SciTech Connect

    Nelson, D.H.; Petrin, R.R.; MacKerrow, E.P.; Schmitt, M.J.; Foy, B.R.; Koskelo, A.C.; McVey, B.D.; Quick, C.R.; Porch, W.M.; Tiee, J.J.; Fite, C.B.; Archuleta, F.A.; Whitehead, M.C.; Walters, D.L.

    1999-03-23

    The measurement sensitivity of CO{sub 2} differential absorption lidar (DIAL) can be affected by a number of different processes. We have previously developed a Huygens-Fresnel wave optics propagation code to simulate the effects of two of these process: effects caused by beam propagation through atmospheric optical turbulence and effects caused by reflective speckle. Atmospheric optical turbulence affects the beam distribution of energy and phase on target. These effects include beam spreading, beam wander and scintillation which can result in increased shot-to-shot signal noise. In addition, reflective speckle alone has been shown to have a major impact on the sensitivity of CO{sub 2} DIAL. However, in real DIAL systems it is a combination of these phenomena, the interaction of atmospheric optical turbulence and reflective speckle, that influences the results. In this work, we briefly review a description of our model including the limitations along with previous simulation s of individual effects. The performance of our modified code with respect to experimental measurements affected by atmospheric optical turbulence and reflective speckle is examined. The results of computer simulations are directly compared with lidar measurements and show good agreement. In addition, advanced studies have been performed to demonstrate the utility of our model in assessing the effects for different lidar geometries on RMS noise and correlation ''size'' in the receiver plane.

  2. Huygens-Fresnel wave-optics simulation of atmospheric optical turbulence and reflective speckle in CO{sub 2} differential absorption lidar (DIAL)

    SciTech Connect

    Nelson, D.; Petrin, R.; MacKerrow, E.; Schmitt, M.; Foy, B.; Koskelo, A.; McVey, B.; Quick, C.; Porch, W.; Fite, C.; Archuleta, F.; Whitehead, M.; Tiee, J.; Walters, D.

    1999-04-01

    The measurement sensitivity of CO{sub 2} differential absorption lidar (DIAL) can be affected by a number of different processes. The authors have previously developed a Huygens-Fresnel wave optics propagation code to simulate the effects of two of these processes: effects caused by beam propagation through atmospheric optical turbulence and effects caused by reflective speckle. Atmospheric optical turbulence affects the beam distribution of energy and phase on target. These effects include beam spreading, beam wander and scintillation which can result in increased shot-to-shot signal noise. In addition, reflective speckle alone has been shown to have a major impact on the sensitivity of CO{sub 2} DIAL. However, in real DIAL systems it is a combination of these phenomena, the interaction of atmospheric optical turbulence and reflective speckle, that influences the results. The performance of the modified code with respect to experimental measurements affected by atmospheric optical turbulence and reflective speckle is examined. The results of computer simulations are directly compared with lidar measurements. The limitations of the model are also discussed. In addition, studies have been performed to determine the importance of key parameters in the simulation. The results of these studies and their impact on the overall results will be presented.

  3. X ray microscope assembly and alignment support and advanced x ray microscope design and analysis

    NASA Technical Reports Server (NTRS)

    Shealy, David L.

    1991-01-01

    Considerable efforts have been devoted recently to the design, analysis, fabrication, and testing of spherical Schwarzschild microscopes for soft x ray application in microscopy and projection lithography. The spherical Schwarzschild microscope consists of two concentric spherical mirrors configured such that the third order spherical aberration and coma are zero. Since multilayers are used on the mirror substrates for x ray applications, it is desirable to have only two reflecting surfaces in a microscope. In order to reduce microscope aberrations and increase the field of view, generalized mirror surface profiles have been considered in this investigation. Based on incoherent and sine wave modulation transfer function (MTF) calculations, the object plane resolution of a microscope has been analyzed as a function of the object height and numerical aperture (NA) of the primary for several spherical Schwarzschild, conic, and aspherical head reflecting two mirror microscope configurations.

  4. Differentials in female labour force participation rates in Indonesia: reflection of economic needs and opportunities, culture or bad data?

    PubMed

    Jones, G

    1986-12-01

    This study investigates regional differentials in female labor force participation rates by educational status in Indonesia, using data from the 1961, 1971, and 1980 censuses. Rates in the Javanese areas are always well above the Indonesian average; in mainly Sundanese West Java they are much lower than the average, and in South Sulawesi they are lower still. Kalimantan is the only region where there is no stability in rates over time, possibly due to the inaccessibility of much of its population for census-taking. When only urban areas are considered, the regional differentials do not alter very much. As in most of the world, participation rates for single women are higher than those of married women, and those for divorced and widowed women are higher still. Participation rates are lowest of all for women with a junior high school education, rise for those witha senior high school education; and rise sharply for those with a university or academy education. The provinces with the highest urban female labor force participation rates--Yogyakarta, Central Java, East Java, and Bali--are among the poorest provinces in Indonesia. Female labor force participation rates in Indonesia are much higher than in other Moslem countries. Geographic and socioeconomic differentials in female labor force participation rates in Indonesia are not an artifact of inconsistencies in the data, but can be related to 2 other sets of explanatory variables: 1) economic needs and opportunities and 2) cultural differences.

  5. Non-linear patterns in age-related DNA methylation may reflect CD4(+) T cell differentiation.

    PubMed

    Johnson, Nicholas D; Wiener, Howard W; Smith, Alicia K; Nishitani, Shota; Absher, Devin M; Arnett, Donna K; Aslibekyan, Stella; Conneely, Karen N

    2017-04-07

    DNA methylation (DNAm) is an important epigenetic process involved in the regulation of gene expression. While many studies have identified thousands of loci associated with age, few have differentiated between linear and non-linear DNAm trends with age. Non-linear trends could indicate early- or late-life gene regulatory processes. Using data from the Illumina 450K array on 336 human peripheral blood samples, we identified 21 CpG sites that associated with age (P<1.03E-7) and exhibited changing rates of DNAm change with age (P<1.94E-6). For two of these CpG sites (cg07955995 and cg22285878), DNAm increased with age at an increasing rate, indicating that differential DNAm was greatest among elderly individuals. We observed significant replication for both CpG sites (P<5.0E-8) in a second set of peripheral blood samples. In 8 of 9 additional datasets comprising samples of monocytes, T cell subtypes, and brain tissue, we observed a pattern directionally consistent with DNAm increasing with age at an increasing rate, which was nominally significant in the three largest datasets (4.3E-15differentiation via the repression of FOXP3. These findings may suggest a possible role for cg07955995 and cg22285878 in immunosenescence.

  6. The Scanning Optical Microscope.

    ERIC Educational Resources Information Center

    Sheppard, C. J. R.

    1978-01-01

    Describes the principle of the scanning optical microscope and explains its advantages over the conventional microscope in the improvement of resolution and contrast, as well as the possibility of producing a picture from optical harmonies generated within the specimen.

  7. Differentiating pediatric epileptic brain tissue from normal brain tissue by using time-dependent diffuse reflectance spectroscopy in vivo: comprehensive data analysis method in the time domain

    NASA Astrophysics Data System (ADS)

    Oh, Sanghoon; Fernald, Bradley; Bhatia, Sanjiv; Ragheb, John; Sandberg, David; Johnson, Mahlon; Lin, Wei-Chiang

    2009-05-01

    This research investigated the feasibility of using time-dependent diffuse reflectance spectroscopy to differentiate pediatric epileptic brain tissue from normal brain tissue. The optical spectroscopic technique monitored the dynamic optical properties of the cerebral cortex that are associated with its physiological, morphological, and compositional characteristics. Due to the transient irregular epileptic discharge activity within the epileptic brain tissue it was hypothesized that the lesion would express abnormal dynamic optical behavior that would alter normal dynamic behavior. Thirteen pediatric epilepsy patients and seven pediatric brain tumor patients (normal controls) were recruited for this clinical study. Dynamic optical properties were obtained from the cortical surface intraoperatively using a timedependent diffuse reflectance spectroscopy system. This system consisted of a fiber-optic probe, a tungsten-halogen light source, and a spectrophotometer. It acquired diffuse reflectance spectra with a spectral range of 204 nm to 932 nm at a rate of 33 spectra per second for approximately 12 seconds. Biopsy samples were taken from electrophysiologically abnormal cortex and evaluated by a neuropathologist, which served as a gold standard for lesion classification. For data analysis, spectral intensity changes of diffuse reflectance in the time domain at two different wavelengths from each investigated site were compared. Negative correlation segment, defined by the periods where the intensity changes at the two wavelengths were opposite in their slope polarity, were extracted. The total duration of negative correlation, referred to as the "negative correlation time index", was calculated by integrating the negative correlation segments. The negative correlation time indices from all investigated sites were sub-grouped according to the corresponding histological classifications. The difference between the mean indices of two subgroups was evaluated by standard

  8. Multispectral reflectance imaging of brain activation in rodents: methodological study of the differential path length estimations and first in vivo recordings in the rat olfactory bulb

    NASA Astrophysics Data System (ADS)

    Renaud, Rémi; Martin, Claire; Gurden, Hirac; Pain, Frédéric

    2012-01-01

    Dynamic maps of relative changes in blood volume and oxygenation following brain activation are obtained using multispectral reflectance imaging. The technique relies on optical absorption modifications linked to hemodynamic changes. The relative variation of hemodynamic parameters can be quantified using the modified Beer-Lambert Law if changes in reflected light intensities are recorded at two wavelengths or more and the differential path length (DP) is known. The DP is the mean path length in tissues of backscattered photons and varies with wavelength. It is usually estimated using Monte Carlo simulations in simplified semi-infinite homogeneous geometries. Here we consider the use of multilayered models of the somatosensory cortex (SsC) and olfactory bulb (OB), which are common physiological models of brain activation. Simulations demonstrate that specific DP estimation is required for SsC and OB, specifically for wavelengths above 600 nm. They validate the hypothesis of a constant path length during activation and show the need for specific DP if imaging is performed in a thinned-skull preparation. The first multispectral reflectance imaging data recorded in vivo during OB activation are presented, and the influence of DP on the hemodynamic parameters and the pattern of oxymetric changes in the activated OB are discussed.

  9. Differentiation of Body Fluid Stains on Fabrics Using External Reflection Fourier Transform Infrared Spectroscopy (FT-IR) and Chemometrics.

    PubMed

    Zapata, Félix; de la Ossa, Ma Ángeles Fernández; García-Ruiz, Carmen

    2016-04-01

    Body fluids are evidence of great forensic interest due to the DNA extracted from them, which allows genetic identification of people. This study focuses on the discrimination among semen, vaginal fluid, and urine stains (main fluids in sexual crimes) placed on different colored cotton fabrics by external reflection Fourier transform infrared spectroscopy (FT-IR) combined with chemometrics. Semen-vaginal fluid mixtures and potential false positive substances commonly found in daily life such as soaps, milk, juices, and lotions were also studied. Results demonstrated that the IR spectral signature obtained for each body fluid allowed its identification and the correct classification of unknown stains by means of principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA). Interestingly, results proved that these IR spectra did not show any bands due to the color of the fabric and no substance of those present in daily life which were analyzed, provided a false positive. © The Author(s) 2016.

  10. TEAM Electron Microscope Animation

    SciTech Connect

    2012-01-01

    The TEAM Electron Microscope, a device that enables atomic-scale imaging in 3-D, has a rotating stage that can hold and position samples inside electron microscopes with unprecedented stability, position-control accuracy, and range of motion.The TEAM Stage makes one of the world's most powerful electron microscopes even better, and enables previously impossible experiments.

  11. Differential effects of early postinjury treatment with neuroprotective drugs in a mouse model using diffuse reflectance spectroscopy

    PubMed Central

    Shochat, Ariel; Abookasis, David

    2015-01-01

    Abstract. The time required for the arrival of an ambulance crew and administration of first aid is critical to clinical outcome, particularly in the case of head injury victims requiring neuroprotective drugs following a car accident, falls, and assaults. Short response times of the medical team, together with proper treatment, can limit injury severity and even save a life before transportation to the nearest medical center. We present a comparative evaluation of five different neuroprotective drugs frequently used in intensive care and operating units in the early phase following traumatic brain injury (TBI): hypertonic saline (HTS), mannitol, morphine, melatonin, and minocycline. The effectiveness of these drugs in terms of changes in brain tissue morphology (cell organelle size, density, distribution, etc.) and biochemical tissue properties (chromophores’ content) was experimentally evaluated through analysis of the spectral reduced scattering and optical absorption coefficient parameters in the near-infrared (NIR) optical range (650 to 1000 nm). Experiments were conducted on anesthetized male mice subjected to a noninvasive closed head weight-drop model of focal TBI (n=50 and n=10 control) and monitored using an NIR diffuse reflectance spectroscopy system utilizing independent source–detector separation and location. After 10 min of baseline measurement, focal TBI was induced and measurements were conducted for 20 min. Subsequently, a neuroprotective drug was administrated and measurements were recorded for another 30 min. This work’s major findings are threefold: first, minocycline was found to improve hemodynamic outcome at the earliest time postinjury. Second, HTS decreased brain water content and inhibited the increase in intracranial pressure. Third, the efficacy of neuroprotective drugs can be monitored noninvasively with diffuse reflectance spectroscopy. The demonstrated ability to noninvasively detect cerebral physiological properties

  12. Differential effects of early postinjury treatment with neuroprotective drugs in a mouse model using diffuse reflectance spectroscopy.

    PubMed

    Shochat, Ariel; Abookasis, David

    2015-01-01

    The time required for the arrival of an ambulance crew and administration of first aid is critical to clinical outcome, particularly in the case of head injury victims requiring neuroprotective drugs following a car accident, falls, and assaults. Short response times of the medical team, together with proper treatment, can limit injury severity and even save a life before transportation to the nearest medical center. We present a comparative evaluation of five different neuroprotective drugs frequently used in intensive care and operating units in the early phase following traumatic brain injury (TBI): hypertonic saline (HTS), mannitol, morphine, melatonin, and minocycline. The effectiveness of these drugs in terms of changes in brain tissue morphology (cell organelle size, density, distribution, etc.) and biochemical tissue properties (chromophores' content) was experimentally evaluated through analysis of the spectral reduced scattering and optical absorption coefficient parameters in the near-infrared (NIR) optical range (650 to 1000 nm). Experiments were conducted on anesthetized male mice subjected to a noninvasive closed head weight-drop model of focal TBI ([Formula: see text] and [Formula: see text] control) and monitored using an NIR diffuse reflectance spectroscopy system utilizing independent source-detector separation and location. After 10 min of baseline measurement, focal TBI was induced and measurements were conducted for 20 min. Subsequently, a neuroprotective drug was administrated and measurements were recorded for another 30 min. This work's major findings are threefold: first, minocycline was found to improve hemodynamic outcome at the earliest time postinjury. Second, HTS decreased brain water content and inhibited the increase in intracranial pressure. Third, the efficacy of neuroprotective drugs can be monitored noninvasively with diffuse reflectance spectroscopy. The demonstrated ability to noninvasively detect cerebral physiological

  13. X ray imaging microscope for cancer research

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.; Shealy, David L.; Brinkley, B. R.; Baker, Phillip C.; Barbee, Troy W., Jr.; Walker, Arthur B. C., Jr.

    1991-01-01

    The NASA technology employed during the Stanford MSFC LLNL Rocket X Ray Spectroheliograph flight established that doubly reflecting, normal incidence multilayer optics can be designed, fabricated, and used for high resolution x ray imaging of the Sun. Technology developed as part of the MSFC X Ray Microscope program, showed that high quality, high resolution multilayer x ray imaging microscopes are feasible. Using technology developed at Stanford University and at the DOE Lawrence Livermore National Laboratory (LLNL), Troy W. Barbee, Jr. has fabricated multilayer coatings with near theoretical reflectivities and perfect bandpass matching for a new rocket borne solar observatory, the Multi-Spectral Solar Telescope Array (MSSTA). Advanced Flow Polishing has provided multilayer mirror substrates with sub-angstrom (rms) smoothnesss for the astronomical x ray telescopes and x ray microscopes. The combination of these important technological advancements has paved the way for the development of a Water Window Imaging X Ray Microscope for cancer research.

  14. Suicide attempters with Borderline Personality Disorder show differential orbitofrontal and parietal recruitment when reflecting on aversive memories

    PubMed Central

    Silvers, Jennifer A.; Hubbard, Alexa D.; Chaudhury, Sadia; Biggs, Emily; Shu, Jocelyn; Grunebaum, Michael F.; Fertuck, Eric; Weber, Jochen; Kober, Hedy; Carson-Wong, Amanda; Brodsky, Beth S.; Chesin, Megan; Ochsner, Kevin N.; Stanley, Barbara

    2016-01-01

    Suicidal behavior and difficulty regulating emotions are hallmarks of Borderline Personality Disorder (BPD). This study examined neural links between emotion regulation and suicide risk in BPD. 60 individuals with BPD (all female, mean age=28.9 years), 46 of whom had attempted suicide, completed a fMRI task involving recalling aversive personal memories. Distance trials assessed the ability to regulate emotion by recalling memories from a third-person, objective viewpoint. Immerse trials assessed emotional reactivity and involved recalling memories from a first-person perspective. Behaviorally, both groups reported less negative affect on Distance as compared to Immerse trials. Neurally, two sets of findings were obtained. The first reflected differences between attempters and non-attempters. When immersing and distancing, attempters showed elevated recruitment of lateral orbitofrontal cortex, a brain region implicated in using negative cues to guide behavior. When distancing, attempters showed diminished recruitment of the precuneus, a region implicated in memory recall and perspective taking. The second set of findings related to individual differences in regulation success – the degree to which individuals used distancing to reduce negative affect. Here, we observed that attempters who successfully regulated exhibited precuneus recruitment that was more similar to non-attempters. These data provide insight into mechanisms underlying suicide attempts in BPD. Future work may examine if these findings generalize to other diagnoses and also whether prior findings in BPD differ across attempters and non-attempters. PMID:27392071

  15. Differential Gene Expression Reflects Morphological Characteristics and Physiological Processes in Rice Immunity against Blast Pathogen Magnaporthe oryzae.

    PubMed

    Azizi, Parisa; Rafii, Mohd Y; Mahmood, Maziah; Abdullah, Siti N A; Hanafi, Mohamed M; Nejat, Naghmeh; Latif, Muhammad A; Sahebi, Mahbod

    2015-01-01

    The rice blast fungus Magnaporthe oryzae is a serious pathogen that jeopardises the world's most important food-security crop. Ten common Malaysian rice varieties were examined for their morphological, physiological and genomic responses to this rice blast pathogen. qPCR quantification was used to assess the growth of the pathogen population in resistant and susceptible rice varieties. The chlorophyll content and photosynthesis were also measured to further understand the disruptive effects that M. oryzae has on infected plants of these varieties. Real-time PCR was used to explore the differential expression of eight blast resistance genes among the ten local varieties. Blast disease has destructive effects on the growth of rice, and the findings of our study provide evidence that the Pikh, Pi9, Pi21, and Osw45 genes are involved in defence responses in the leaves of Malaysian rice at 31 h after inoculation with M. oryzae pathotype P7.2. Both the chlorophyll content and photosynthesis were reduced, but the levels of Pikh gene expression remained constant in susceptible varieties, with a developed pathogen population and mild or severe symptoms. The Pi9, Pi21, and Osw45 genes, however, were simultaneously upregulated in infected rice plants. Therefore, the presence of the Pikh, Pi9, Pi21, and Osw45 genes in the germplasm is useful for improving the resistance of rice varieties.

  16. Differential Gene Expression Reflects Morphological Characteristics and Physiological Processes in Rice Immunity against Blast Pathogen Magnaporthe oryzae

    PubMed Central

    Mahmood, Maziah; Abdullah, Siti N. A.; Hanafi, Mohamed M.; Nejat, Naghmeh; Latif, Muhammad A.

    2015-01-01

    The rice blast fungus Magnaporthe oryzae is a serious pathogen that jeopardises the world’s most important food-security crop. Ten common Malaysian rice varieties were examined for their morphological, physiological and genomic responses to this rice blast pathogen. qPCR quantification was used to assess the growth of the pathogen population in resistant and susceptible rice varieties. The chlorophyll content and photosynthesis were also measured to further understand the disruptive effects that M. oryzae has on infected plants of these varieties. Real-time PCR was used to explore the differential expression of eight blast resistance genes among the ten local varieties. Blast disease has destructive effects on the growth of rice, and the findings of our study provide evidence that the Pikh, Pi9, Pi21, and Osw45 genes are involved in defence responses in the leaves of Malaysian rice at 31 h after inoculation with M. oryzae pathotype P7.2. Both the chlorophyll content and photosynthesis were reduced, but the levels of Pikh gene expression remained constant in susceptible varieties, with a developed pathogen population and mild or severe symptoms. The Pi9, Pi21, and Osw45 genes, however, were simultaneously upregulated in infected rice plants. Therefore, the presence of the Pikh, Pi9, Pi21, and Osw45 genes in the germplasm is useful for improving the resistance of rice varieties. PMID:26001124

  17. Signaling pathways in aged T cells – a reflection of T cell differentiation, cell senescence and host environment

    PubMed Central

    Goronzy, Jörg J.; Li, Guangjin; Yu, Mingcan; Weyand, Cornelia M.

    2012-01-01

    With increasing age, the ability of the immune system to protect against new antigenic challenges or to control chronic infections erodes. Decline in thymic function and cumulating antigenic experiences of acute and chronic infections threaten T cell homeostasis, but insufficiently explain the failing immune competence and the increased susceptibility for autoimmunity. Alterations in signaling pathways in the aging T cells account for many of the age-related defects. Signaling threshold calibrations seen with aging frequently built on mechanisms that are operational in T cell development and T cell differentiation or are adaptations to the changing environment in the aging host. Age-related changes in transcription of receptors and signaling molecules shift the balance towards inhibitory pathways, most dominantly seen in CD8 T cells and to a lesser degree in CD4 T cells. Prominent examples are the expression of negative regulatory receptors of the CD28 and the TNF receptor superfamilies as well the expression of various cytoplasmic and nuclear dual-specific phosphatases. PMID:22560928

  18. Scanning Microscopes Using X Rays and Microchannels

    NASA Technical Reports Server (NTRS)

    Wang, Yu

    2003-01-01

    Scanning microscopes that would be based on microchannel filters and advanced electronic image sensors and that utilize x-ray illumination have been proposed. Because the finest resolution attainable in a microscope is determined by the wavelength of the illumination, the xray illumination in the proposed microscopes would make it possible, in principle, to achieve resolutions of the order of nanometers about a thousand times as fine as the resolution of a visible-light microscope. Heretofore, it has been necessary to use scanning electron microscopes to obtain such fine resolution. In comparison with scanning electron microscopes, the proposed microscopes would likely be smaller, less massive, and less expensive. Moreover, unlike in scanning electron microscopes, it would not be necessary to place specimens under vacuum. The proposed microscopes are closely related to the ones described in several prior NASA Tech Briefs articles; namely, Miniature Microscope Without Lenses (NPO-20218), NASA Tech Briefs, Vol. 22, No. 8 (August 1998), page 43; and Reflective Variants of Miniature Microscope Without Lenses (NPO-20610), NASA Tech Briefs, Vol. 26, No. 9 (September 2002) page 6a. In all of these microscopes, the basic principle of design and operation is the same: The focusing optics of a conventional visible-light microscope are replaced by a combination of a microchannel filter and a charge-coupled-device (CCD) image detector. A microchannel plate containing parallel, microscopic-cross-section holes much longer than they are wide is placed between a specimen and an image sensor, which is typically the CCD. The microchannel plate must be made of a material that absorbs the illuminating radiation reflected or scattered from the specimen. The microchannels must be positioned and dimensioned so that each one is registered with a pixel on the image sensor. Because most of the radiation incident on the microchannel walls becomes absorbed, the radiation that reaches the

  19. Water window imaging x ray microscope

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B. (Inventor)

    1992-01-01

    A high resolution x ray microscope for imaging microscopic structures within biological specimens has an optical system including a highly polished primary and secondary mirror coated with identical multilayer coatings, the mirrors acting at normal incidence. The coatings have a high reflectivity in the narrow wave bandpass between 23.3 and 43.7 angstroms and have low reflectivity outside of this range. The primary mirror has a spherical concave surface and the secondary mirror has a spherical convex surface. The radii of the mirrors are concentric about a common center of curvature on the optical axis of the microscope extending from the object focal plane to the image focal plane. The primary mirror has an annular configuration with a central aperture and the secondary mirror is positioned between the primary mirror and the center of curvature for reflecting radiation through the aperture to a detector. An x ray filter is mounted at the stage end of the microscope, and film sensitive to x rays in the desired band width is mounted in a camera at the image plane of the optical system. The microscope is mounted within a vacuum chamber for minimizing the absorption of x rays in air from a source through the microscope.

  20. A Simple low-cost device enables four epi-illumination techniques on standard light microscopes

    PubMed Central

    Ishmukhametov, Robert R.; Russell, Aidan N.; Wheeler, Richard J.; Nord, Ashley L.; Berry, Richard M.

    2016-01-01

    Back-scattering darkfield (BSDF), epi-fluorescence (EF), interference reflection contrast (IRC), and darkfield surface reflection (DFSR) are advanced but expensive light microscopy techniques with limited availability. Here we show a simple optical design that combines these four techniques in a simple low-cost miniature epi-illuminator, which inserts into the differential interference-contrast (DIC) slider bay of a commercial microscope, without further additions required. We demonstrate with this device: 1) BSDF-based detection of Malarial parasites inside unstained human erythrocytes; 2) EF imaging with and without dichroic components, including detection of DAPI-stained Leishmania parasite without using excitation or emission filters; 3) RIC of black lipid membranes and other thin films, and 4) DFSR of patterned opaque and transparent surfaces. We believe that our design can expand the functionality of commercial bright field microscopes, provide easy field detection of parasites and be of interest to many users of light microscopy. PMID:26853732

  1. A Simple low-cost device enables four epi-illumination techniques on standard light microscopes.

    PubMed

    Ishmukhametov, Robert R; Russell, Aidan N; Wheeler, Richard J; Nord, Ashley L; Berry, Richard M

    2016-02-08

    Back-scattering darkfield (BSDF), epi-fluorescence (EF), interference reflection contrast (IRC), and darkfield surface reflection (DFSR) are advanced but expensive light microscopy techniques with limited availability. Here we show a simple optical design that combines these four techniques in a simple low-cost miniature epi-illuminator, which inserts into the differential interference-contrast (DIC) slider bay of a commercial microscope, without further additions required. We demonstrate with this device: 1) BSDF-based detection of Malarial parasites inside unstained human erythrocytes; 2) EF imaging with and without dichroic components, including detection of DAPI-stained Leishmania parasite without using excitation or emission filters; 3) RIC of black lipid membranes and other thin films, and 4) DFSR of patterned opaque and transparent surfaces. We believe that our design can expand the functionality of commercial bright field microscopes, provide easy field detection of parasites and be of interest to many users of light microscopy.

  2. A Simple low-cost device enables four epi-illumination techniques on standard light microscopes

    NASA Astrophysics Data System (ADS)

    Ishmukhametov, Robert R.; Russell, Aidan N.; Wheeler, Richard J.; Nord, Ashley L.; Berry, Richard M.

    2016-02-01

    Back-scattering darkfield (BSDF), epi-fluorescence (EF), interference reflection contrast (IRC), and darkfield surface reflection (DFSR) are advanced but expensive light microscopy techniques with limited availability. Here we show a simple optical design that combines these four techniques in a simple low-cost miniature epi-illuminator, which inserts into the differential interference-contrast (DIC) slider bay of a commercial microscope, without further additions required. We demonstrate with this device: 1) BSDF-based detection of Malarial parasites inside unstained human erythrocytes; 2) EF imaging with and without dichroic components, including detection of DAPI-stained Leishmania parasite without using excitation or emission filters; 3) RIC of black lipid membranes and other thin films, and 4) DFSR of patterned opaque and transparent surfaces. We believe that our design can expand the functionality of commercial bright field microscopes, provide easy field detection of parasites and be of interest to many users of light microscopy.

  3. Low MMP-8/TIMP-1 reflects left ventricle impairment in takotsubo cardiomyopathy and high TIMP-1 may help to differentiate it from acute coronary syndrome

    PubMed Central

    Parkkonen, Olavi; Nieminen, Mikko T.; Vesterinen, Paula; Tervahartiala, Taina; Perola, Markus; Salomaa, Veikko; Jousilahti, Pekka; Sorsa, Timo; Pussinen, Pirkko J.; Sinisalo, Juha

    2017-01-01

    Background Matrix metalloproteinase 8 (MMP-8) is the most potent type-I collagen protease. Such collagen mainly constitutes the transient fibrosis in takotsubo cardiomyopathy (TTC) endomyocardial biopsies. High MMP-8 and tissue-inhibitor of matrix metalloproteinase-1 (TIMP-1) levels are implicated in acute coronary syndrome (ACS). We compared MMP-8 and TIMP-1 levels in consecutive TTC and ACS patients, and their association to TTC severity. Methods and results In 45 acute serum samples of TTC, 2072 ACS and 1000 controls, TIMP-1 differed between ACS 146.7ng/mL (115.0–186.3) (median (interquartile range)), TTC 115.7 (94.3–137.7) and controls 80.9 (73.2–90.4), (p<0.0001). MMP-8 levels were similar between ACS and TTC. In receiver-operating characteristics analysis, TIMP-1 differentiated TTC from ACS with an area under the curve (AUC) of 0.679 (p<0.0001) surpassing troponin T (TnT) at 0.522 (p = 0.66). Compared to other differing factors (age, sex, smoking), TIMP-1 improved diagnostic specificity and sensitivity from AUC of 0.821 to 0.844 (p = 0.007). The MMP8/TIMP-1 molar ratio differentiated normal ejection fraction (EF) at 0.27 (0.13–0.51) from decreased EF<50% at 0.08 (0.05–0.20), (p = 0.04) in TTC, but not in ACS. Conclusions Even with other differing factors considered, TIMP-1 differentiated TTC from ACS better than TnT. In TTC, the low MMP-8/TIMP-1 molar ratio may reflect decreased proteolysis and increased transient fibrosis, perhaps in part explaining the left-ventricle impairment. PMID:28278213

  4. Present spatial diversity patterns of Theobroma cacao L. in the neotropics reflect genetic differentiation in pleistocene refugia followed by human-influenced dispersal.

    PubMed

    Thomas, Evert; van Zonneveld, Maarten; Loo, Judy; Hodgkin, Toby; Galluzzi, Gea; van Etten, Jacob

    2012-01-01

    Cacao (Theobroma cacao L.) is indigenous to the Amazon basin, but is generally believed to have been domesticated in Mesoamerica for the production of chocolate beverage. However, cacao's distribution of genetic diversity in South America is also likely to reflect pre-Columbian human influences that were superimposed on natural processes of genetic differentiation. Here we present the results of a spatial analysis of the intra-specific diversity of cacao in Latin America, drawing on a dataset of 939 cacao trees genotypically characterized by means of 96 SSR markers. To assess continental diversity patterns we performed grid-based calculations of allelic richness, Shannon diversity and Nei gene diversity, and distinguished different spatially coherent genetic groups by means of cluster analysis. The highest levels of genetic diversity were observed in the Upper Amazon areas from southern Peru to the Ecuadorian Amazon and the border areas between Colombia, Peru and Brazil. On the assumption that the last glaciation (22,000-13,000 BP) had the greatest pre-human impact on the current distribution and diversity of cacao, we modeled the species' Pleistocene niche suitability and overlaid this with present-day diversity maps. The results suggest that cacao was already widely distributed in the Western Amazon before the onset of glaciation. During glaciations, cacao populations were likely to have been restricted to several refugia where they probably underwent genetic differentiation, resulting in a number of genetic clusters which are representative for, or closest related to, the original wild cacao populations. The analyses also suggested that genetic differentiation and geographical distribution of a number of other clusters seem to have been significantly affected by processes of human management and accompanying genetic bottlenecks. We discuss the implications of these results for future germplasm collection and in situ, on farm and ex situ conservation of cacao.

  5. Present Spatial Diversity Patterns of Theobroma cacao L. in the Neotropics Reflect Genetic Differentiation in Pleistocene Refugia Followed by Human-Influenced Dispersal

    PubMed Central

    Thomas, Evert; van Zonneveld, Maarten; Loo, Judy; Hodgkin, Toby; Galluzzi, Gea; van Etten, Jacob

    2012-01-01

    Cacao (Theobroma cacao L.) is indigenous to the Amazon basin, but is generally believed to have been domesticated in Mesoamerica for the production of chocolate beverage. However, cacao’s distribution of genetic diversity in South America is also likely to reflect pre-Columbian human influences that were superimposed on natural processes of genetic differentiation. Here we present the results of a spatial analysis of the intra-specific diversity of cacao in Latin America, drawing on a dataset of 939 cacao trees genotypically characterized by means of 96 SSR markers. To assess continental diversity patterns we performed grid-based calculations of allelic richness, Shannon diversity and Nei gene diversity, and distinguished different spatially coherent genetic groups by means of cluster analysis. The highest levels of genetic diversity were observed in the Upper Amazon areas from southern Peru to the Ecuadorian Amazon and the border areas between Colombia, Peru and Brazil. On the assumption that the last glaciation (22,000–13,000 BP) had the greatest pre-human impact on the current distribution and diversity of cacao, we modeled the species’ Pleistocene niche suitability and overlaid this with present-day diversity maps. The results suggest that cacao was already widely distributed in the Western Amazon before the onset of glaciation. During glaciations, cacao populations were likely to have been restricted to several refugia where they probably underwent genetic differentiation, resulting in a number of genetic clusters which are representative for, or closest related to, the original wild cacao populations. The analyses also suggested that genetic differentiation and geographical distribution of a number of other clusters seem to have been significantly affected by processes of human management and accompanying genetic bottlenecks. We discuss the implications of these results for future germplasm collection and in situ, on farm and ex situ conservation of

  6. Cryogenic immersion microscope

    DOEpatents

    Le Gros, Mark; Larabell, Carolyn A.

    2010-12-14

    A cryogenic immersion microscope whose objective lens is at least partially in contact with a liquid reservoir of a cryogenic liquid, in which reservoir a sample of interest is immersed is disclosed. When the cryogenic liquid has an index of refraction that reduces refraction at interfaces between the lens and the sample, overall resolution and image quality are improved. A combination of an immersion microscope and x-ray microscope, suitable for imaging at cryogenic temperatures is also disclosed.

  7. Thermal-Wave Microscope

    NASA Technical Reports Server (NTRS)

    Jones, Robert E.; Kramarchuk, Ihor; Williams, Wallace D.; Pouch, John J.; Gilbert, Percy

    1989-01-01

    Computer-controlled thermal-wave microscope developed to investigate III-V compound semiconductor devices and materials. Is nondestructive technique providing information on subsurface thermal features of solid samples. Furthermore, because this is subsurface technique, three-dimensional imaging also possible. Microscope uses intensity-modulated electron beam of modified scanning electron microscope to generate thermal waves in sample. Acoustic waves generated by thermal waves received by transducer and processed in computer to form images displayed on video display of microscope or recorded on magnetic disk.

  8. Reflecting Reflective Practice

    ERIC Educational Resources Information Center

    Galea, Simone

    2012-01-01

    This paper demystifies reflective practice on teaching by focusing on the idea of reflection itself and how it has been conceived by two philosophers, Plato and Irigaray. It argues that reflective practice has become a standardized method of defining the teacher in teacher education and teacher accreditation systems. It explores how practices of…

  9. Reflecting Reflective Practice

    ERIC Educational Resources Information Center

    Galea, Simone

    2012-01-01

    This paper demystifies reflective practice on teaching by focusing on the idea of reflection itself and how it has been conceived by two philosophers, Plato and Irigaray. It argues that reflective practice has become a standardized method of defining the teacher in teacher education and teacher accreditation systems. It explores how practices of…

  10. Mailing microscope slides

    USDA-ARS?s Scientific Manuscript database

    Many insects feed agriculturally important crops, trees, and ornamental plants and cause millions of dollars of damage annually. Identification for some of these require the preparation of a microscope slide for examination. There are times when a microscope slide may need to be sent away to a speci...

  11. The Homemade Microscope.

    ERIC Educational Resources Information Center

    Baker, Roger C., Jr.

    1991-01-01

    Directions for the building of a pocket microscope that will make visible the details of insect structure and living bacteria are described. Background information on the history of microscopes and lenses is provided. The procedures for producing various types of lenses are included. (KR)

  12. The Light Microscope.

    ERIC Educational Resources Information Center

    Baker, W. L.

    1995-01-01

    Describes the function of the various parts of the microscope and their integration in the formation of an optical image. Presents a procedure for setting up a microscope to obtain maximum resolution and contrast for each objective lens at all magnifications. (JRH)

  13. The Homemade Microscope.

    ERIC Educational Resources Information Center

    Baker, Roger C., Jr.

    1991-01-01

    Directions for the building of a pocket microscope that will make visible the details of insect structure and living bacteria are described. Background information on the history of microscopes and lenses is provided. The procedures for producing various types of lenses are included. (KR)

  14. Photography through the Microscope.

    ERIC Educational Resources Information Center

    McNeil, D. W.

    1992-01-01

    Describes how to illuminate and optically stain slides for microscope use and how to interface a 35mm camera with a microscope using an adaptor. Provides equipment descriptions and sources, details about illumination, image formation, darkfield adaptors, centerable filter adaptors, darkfield stops, rheinburg filters, and choosing specimens to…

  15. Mars Life? - Microscopic Structures

    NASA Image and Video Library

    1996-08-09

    In the center of this electron microscope image of a small chip from a meteorite are several tiny structures that are possible microscopic fossils of primitive, bacteria-like organisms that may have lived on Mars more than 3.6 billion years ago. http://photojournal.jpl.nasa.gov/catalog/PIA00283

  16. High-Density Lipoprotein Proteomic Composition, and not Efflux Capacity, Reflects Differential Modulation of Reverse Cholesterol Transport by Saturated and Monounsaturated Fat Diets.

    PubMed

    O'Reilly, Marcella; Dillon, Eugene; Guo, Weili; Finucane, Orla; McMorrow, Aoibheann; Murphy, Aoife; Lyons, Claire; Jones, Daniel; Ryan, Miriam; Gibney, Michael; Gibney, Eileen; Brennan, Lorraine; de la Llera Moya, Margarita; Reilly, Muredach P; Roche, Helen M; McGillicuddy, Fiona C

    2016-05-10

    Acute inflammation impairs reverse cholesterol transport (RCT) and reduces high-density lipoprotein (HDL) function in vivo. This study hypothesized that obesity-induced inflammation impedes RCT and alters HDL composition, and investigated if dietary replacement of saturated (SFA) for monounsaturated (MUFA) fatty acids modulates RCT. Macrophage-to-feces RCT, HDL efflux capacity, and HDL proteomic profiling was determined in C57BL/6j mice following 24 weeks on SFA- or MUFA-enriched high-fat diets (HFDs) or low-fat diet. The impact of dietary SFA consumption and insulin resistance on HDL efflux function was also assessed in humans. Both HFDs increased plasma (3)H-cholesterol counts during RCT in vivo and ATP-binding cassette, subfamily A, member 1-independent efflux to plasma ex vivo, effects that were attributable to elevated HDL cholesterol. By contrast, ATP-binding cassette, subfamily A, member 1-dependent efflux was reduced after both HFDs, an effect that was also observed with insulin resistance and high SFA consumption in humans. SFA-HFD impaired liver-to-feces RCT, increased hepatic inflammation, and reduced ABC subfamily G member 5/8 and ABC subfamily B member 11 transporter expression in comparison with low-fat diet, whereas liver-to-feces RCT was preserved after MUFA-HFD. HDL particles were enriched with acute-phase proteins (serum amyloid A, haptoglobin, and hemopexin) and depleted of paraoxonase-1 after SFA-HFD in comparison with MUFA-HFD. Ex vivo efflux assays validated increased macrophage-to-plasma RCT in vivo after both HFDs but failed to capture differential modulation of hepatic cholesterol trafficking. By contrast, proteomics revealed the association of hepatic-derived inflammatory proteins on HDL after SFA-HFD in comparison with MUFA-HFD, which reflected differential hepatic cholesterol trafficking between groups. Acute-phase protein levels on HDL may serve as novel biomarkers of impaired liver-to-feces RCT in vivo. © 2016 The Authors.

  17. Links between microscopic and macroscopic fluid mechanics

    NASA Astrophysics Data System (ADS)

    Hoover, Wm. G.; Hoover, C. G.

    2003-01-01

    The microscopic and macroscopic versions of fluid mechanics differ qualitatively. Microscopic particles obey time-reversible ordinary differential equations. The resulting particle trajectories {q(t)} may be time-averaged or ensemble-averaged so as to generate field quantities corresponding to macroscopic variables. On the other hand, the macroscopic continuum fields described by fluid mechanics follow irreversible partial differential equations. Smooth particle methods bridge the gap separating these two views of fluids by solving the macroscopic field equations with particle dynamics that resemble molecular dynamics. Recently, nonlinear dynamics have provided some useful tools for understanding the relationship between the microscopic and macroscopic points of view. Chaos and fractals play key roles in this new understanding. Non-equilibrium phase-space averages look very different from their equilibrium counterparts. Away from equilibrium the smooth phase-space distributions are replaced by fractional-dimensional singular distributions that exhibit time irreversibility.

  18. [Microscopic colitis: update 2014].

    PubMed

    Burgmann, Konstantin; Fraga, Montserrat; Schoepfer, Alain M; Yun, Pu

    2014-09-03

    Microscopic colitis, which includes lymphocytic colitis and collagenous colitis, represents a frequent cause of chronic watery diarrhea especially in the elderly population. Several medications, such as nonsteroidal antiinflammatory drugs, proton pump inhibitors or antidepressants, as well as cigarette smoking have been recognized as risk factors for microscopic colitis. The diagnosis of microscopic colitis is based on a macroscopically normal ileo-colonoscopy and several biopsies from the entire colon, which demonstrate the pathognomonic histopathologic findings. Therapy is mainly based on the use of budesonide. Other medications, such as mesalazine, cholestyramine and bismuth, have been evaluated as well but the evidence is less solid.

  19. Mars Life? - Microscopic Structures

    NASA Technical Reports Server (NTRS)

    1996-01-01

    In the center of this electron microscope image of a small chip from a meteorite are several tiny structures that are possible microscopic fossils of primitive, bacteria-like organisms that may have lived on Mars more than 3.6 billion years ago. A two-year investigation by a NASA research team found organic molecules, mineral features characteristic of biological activity and possible microscopic fossils such as these inside of an ancient Martian rock that fell to Earth as a meteorite. The largest possible fossils are less than 1/100th the diameter of a human hair in size while most are ten times smaller.

  20. Terrestrial Clay under Microscope

    NASA Image and Video Library

    2008-09-30

    A scanning electron microscope captured this image of terresterial soil containing a phyllosilicate mineral from Koua Bocca, Ivory Coast, West Africa. This soil shares some similarities with Martian soil scooped by NASA Phoenix Lander.

  1. Assessment of Petrological Microscopes.

    ERIC Educational Resources Information Center

    Mathison, Charter Innes

    1990-01-01

    Presented is a set of procedures designed to check the design, ergonomics, illumination, function, optics, accessory equipment, and image quality of a microscope being considered for purchase. Functions for use in a petrology or mineralogy laboratory are stressed. (CW)

  2. Microscope collision protection apparatus

    DOEpatents

    DeNure, Charles R.

    2001-10-23

    A microscope collision protection apparatus for a remote control microscope which protects the optical and associated components from damage in the event of an uncontrolled collision with a specimen, regardless of the specimen size or shape. In a preferred embodiment, the apparatus includes a counterbalanced slide for mounting the microscope's optical components. This slide replaces the rigid mounts on conventional upright microscopes with a precision ball bearing slide. As the specimen contacts an optical component, the contacting force will move the slide and the optical components mounted thereon. This movement will protect the optical and associated components from damage as the movement causes a limit switch to be actuated, thereby stopping all motors responsible for the collision.

  3. Assessment of Petrological Microscopes.

    ERIC Educational Resources Information Center

    Mathison, Charter Innes

    1990-01-01

    Presented is a set of procedures designed to check the design, ergonomics, illumination, function, optics, accessory equipment, and image quality of a microscope being considered for purchase. Functions for use in a petrology or mineralogy laboratory are stressed. (CW)

  4. UV-visible microscope spectrophotometric polarization and dichroism with increased discrimination power in forensic analysis

    NASA Astrophysics Data System (ADS)

    Purcell, Dale Kevin

    Microanalysis of transfer (Trace) evidence is the application of a microscope and microscopical techniques for the collection, observation, documentation, examination, identification, and discrimination of micrometer sized particles or domains. Microscope spectrophotometry is the union of microscopy and spectroscopy for microanalysis. Analytical microspectroscopy is the science of studying the emission, reflection, transmission, and absorption of electromagnetic radiation to determine the structure or chemical composition of microscopic-size materials. Microscope spectrophotometry instrument designs have evolved from monochromatic illumination which transmitted through the microscope and sample and then is detected by a photometer detector (photomultiplier tube) to systems in which broad-band (white light) illumination falls incident upon a sample followed by a non-scanning grating spectrometer equipped with a solid-state multi-element detector. Most of these small modern spectrometers are configured with either silicon based charged-couple device detectors (200-950 nm) or InGaAs based diode array detectors (850-2300 nm) with computerized data acquisition and signal processing being common. A focus of this research was to evaluate the performance characteristics of various modern forensic (UV-Vis) microscope photometer systems as well as review early model instrumental designs. An important focus of this research was to efficiently measure ultraviolet-visible spectra of microscopically small specimens for classification, differentiation, and possibly individualization. The first stage of the project consisted of the preparation of microscope slides containing neutral density filter reference materials, molecular fluorescence reference materials, and dichroic reference materials. Upon completion of these standard slide preparations analysis began with measurements in order to evaluate figures of merit for comparison of the instruments investigated. The figures of

  5. Hypoxia in Microscopic Tumors

    PubMed Central

    Li, Xiao-Feng; O’Donoghue, Joseph A

    2008-01-01

    Tumor hypoxia has been commonly observed in a broad spectrum of primary solid malignancies. Hypoxia is associated with tumor progression, increased aggressiveness, enhanced metastatic potential and poor prognosis. Hypoxic tumor cells are resistant to radiotherapy and some forms of chemotherapy. Using an animal model, we recently showed that microscopic tumors less than 1 mm diameter were severely hypoxic. In this review, models and techniques for the study of hypoxia in microscopic tumors are discussed. PMID:18384940

  6. [Stereo microscope, neglected tool].

    PubMed

    Gacek, Grzegorz

    2017-01-01

    Stereoscopes, in author opinion, are neglected tools in modern biology. This article shortly describes technical and application capabilities of the present stereomicroscopes. The two main types of stereomicroscope construction are depicted: Greenough microscope and Common Main Objective microscope. The technological breakthrough, asymmetrical optical design of stereomicroscopes, the Fusion Optics, is presented too. Because of very wide offer of a stereomicroscope platforms, illumination systems, software and imaging systems, the article contains also very useful factors to consider when selecting a stereomicroscope.

  7. Microscopic Theory of Fission

    SciTech Connect

    Younes, W.; Gogny, D.

    2008-04-17

    In recent years, the microscopic method has been applied to the notoriously difficult problem of nuclear fission with unprecedented success. In this paper, we discuss some of the achievements and promise of the microscopic method, as embodied in the Hartree-Fock method using the Gogny finite-range effective interaction, and beyond-mean-field extensions to the theory. The nascent program to describe induced fission observables using this approach at the Lawrence Livermore National Laboratory is presented.

  8. Operating microscopes: past, present, and future.

    PubMed

    Uluç, Kutluay; Kujoth, Gregory C; Başkaya, Mustafa K

    2009-09-01

    The operating microscope is a fixture of modern surgical facilities, and it is a critically important factor in the success of many of the most complex and difficult surgical interventions used in medicine today. The rise of this key surgical tool reflects advances in understanding the principles of optics and vision that have occurred over centuries. The development of reading spectacles in the late 13th century led to the construction of early compound microscopes in the 16th and 17th centuries by Lippershey, Janssen, Galileo, Hooke, and others. Perhaps surprisingly, Leeuwenhoek's simple microscopes of this era offered improved performance over his contemporaries' designs. The intervening years saw improvements that reduced the spherical and chromatic aberrations present in compound microscopes. By the late 19th century, Carl Zeiss and Ernst Abbe ushered the compound microscope into the beginnings of the modern era of commercial design and production. The introduction of the microscope into the operating room by Nylén in 1921 initiated a revolution in surgical practice that gained momentum throughout the 1950s with multiple refinements, the introduction of the Zeiss OPMI series, and Kurze's application of the microscope to neurosurgery in 1957. Many of the refinements of the last 50 years have greatly improved the handling and practical operation of the surgical microscope, considerations which are equally important to its optical performance. Today's sophisticated operating microscopes allow for advanced real-time angiographic and tumor imaging. In this paper the authors discuss what might be found in the operating rooms of tomorrow.

  9. Microscopic colitis: a review.

    PubMed

    Farrukh, A; Mayberry, J F

    2014-12-01

    In recent years, microscopic colitis has been increasingly diagnosed. This review was carried out to evaluate demographic factors for microscopic colitis and to perform a systematic assessment of available treatment options. Relevant publications up to December 2013 were identified following searches of PubMed and Google Scholar using the key words 'microscopic colitis', 'collagenous colitis' and 'lymphocytic colitis'. Two-hundred and forty-eight articles were identified. The term microscopic colitis includes lymphocytic colitis and collagenous colitis. Both have common clinical symptoms but are well defined histopathologically. The clinical course is usually benign, but serious complications, including death, may occur. A peak incidence from 60 to 70 years of age with a female preponderance is observed. Although most cases are idiopathic, associations with autoimmune disorders, such as coeliac disease and hypothyroidism, as well as with exposure to nonsteroidal anti-inflammatory drugs and proton-pump inhibitors, have been observed. The incidence and prevalence of microscopic colitis is rising and good-quality epidemiological research is needed. Treatment is currently largely based on anecdotal evidence and on results from limited clinical trials of budesonide. Long-term follow-up of these patients is not well established. The review synthesizes work on the definition of microscopic colitis and the relationship between collagenous and lymphocytic colitis. It reviews the international epidemiology and work on aetiology. In addition, it critically considers the efficacy of a range of treatments. Colorectal Disease © 2014 The Association of Coloproctology of Great Britain and Ireland.

  10. The virtual microscope.

    PubMed

    Catalyürek, Umit; Beynon, Michael D; Chang, Chialin; Kurc, Tahsin; Sussman, Alan; Saltz, Joel

    2003-12-01

    We present the design and implementation of the Virtual Microscope, a software system employing a client/server architecture to provide a realistic emulation of a high power light microscope. The system provides a form of completely digital telepathology, allowing simultaneous access to archived digital slide images by multiple clients. The main problem the system targets is storing and processing the extremely large quantities of data required to represent a collection of slides. The Virtual Microscope client software runs on the end user's PC or workstation, while database software for storing, retrieving and processing the microscope image data runs on a parallel computer or on a set of workstations at one or more potentially remote sites. We have designed and implemented two versions of the data server software. One implementation is a customization of a database system framework that is optimized for a tightly coupled parallel machine with attached local disks. The second implementation is component-based, and has been designed to accommodate access to and processing of data in a distributed, heterogeneous environment. We also have developed caching client software, implemented in Java, to achieve good response time and portability across different computer platforms. The performance results presented show that the Virtual Microscope systems scales well, so that many clients can be adequately serviced by an appropriately configured data server.

  11. Integrated elastic microscope device

    NASA Astrophysics Data System (ADS)

    Lee, W. M.; Wright, D.; Watkins, R.; Cen, Zi

    2015-03-01

    The growing power of imaging and computing power of smartphones is creating the possibility of converting your smartphone into a high power pocket microscopy system. High quality miniature microscopy lenses attached to smartphone are typically made with glass or plastics that can only be produce at low cost with high volume. To revise the paradigm of microscope lenses, we devised a simple droplet lens fabrication technique that which produces low cost and high performance lens. Each lens is integrated into thin 3-D printed holder with complimentary light emitted diode (LEDs) that clips onto majority of smartphones. The integrated device converts a smartphone into a high power optical microscope/dermatoscope at around $2. This low cost device has wide application in a multitude of practical uses such as material inspection, dermascope and educational microscope.

  12. Electron microscope studies

    SciTech Connect

    Crewe, A.V.; Kapp, O.H.

    1992-07-01

    This is a report covering the research performed in the Crewe laboratory between 1964 and 1992. Because of limitations of space we have provided relatively brief summaries of the major research directions of the facility during these years. A complete bibliography has been included and we have referenced groups of pertinent publications at the beginning of each section. This report summarizes our efforts to develop better electron microscopes and chronicles many of the experimental programs, in materials science and biology, that acted both as a stimulus to better microscope design and also as a testing ground for many instrumental innovations.

  13. Making Art with Microscopes

    ERIC Educational Resources Information Center

    Benedis-Grab, Gregory

    2011-01-01

    Interdisciplinary teaching is a great way to focus on overarching concepts and help students make connections across disciplines. Historically, art and science have been connected disciplines. The botanical prints of the 18th and 19th centuries and early work with microscopes are two examples of a need for strong artistic skills in the science…

  14. Microscope on Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image taken at Meridiani Planum, Mars by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's microscopic imager (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  15. Microscope on Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image taken at Meridiani Planum, Mars by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's microscopic imager (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  16. Making Art with Microscopes

    ERIC Educational Resources Information Center

    Benedis-Grab, Gregory

    2011-01-01

    Interdisciplinary teaching is a great way to focus on overarching concepts and help students make connections across disciplines. Historically, art and science have been connected disciplines. The botanical prints of the 18th and 19th centuries and early work with microscopes are two examples of a need for strong artistic skills in the science…

  17. Reflective Teaching

    ERIC Educational Resources Information Center

    Farrell, Thomas S. C.

    2013-01-01

    Thomas Farrell's "Reflective Teaching" outlines four principles that take teachers from just doing reflection to making it a way of being. Using the four principles, Reflective Practice Is Evidence Based, Reflective Practice Involves Dialogue, Reflective Practice Links Beliefs and Practices, and Reflective Practice Is a Way of Life,…

  18. Design and analysis of multilayer x ray/XUV microscope

    NASA Technical Reports Server (NTRS)

    Shealy, David L.

    1990-01-01

    The design and analysis of a large number of normal incidence multilayer x ray microscopes based on the spherical mirror Schwarzschild configuration is examined. Design equations for the spherical mirror Schwarzschild microscopes are summarized and used to evaluate mirror parameters for microscopes with magnifications ranging from 2 to 50x. Ray tracing and diffraction analyses are carried out for many microscope configurations to determine image resolution as a function of system parameters. The results are summarized in three publication included herein. A preliminary study of advanced reflecting microscope configurations, where aspherics are used in place of the spherical microscope mirror elements, has indicated that the aspherical elements will improve off-axis image resolution and increase the effective field of view.

  19. Theoretical model of the helium pinhole microscope

    NASA Astrophysics Data System (ADS)

    Palau, Adrià Salvador; Bracco, Gianangelo; Holst, Bodil

    2016-12-01

    In recent years, the development of neutral helium microscopes has gained increasing interest. The low energy, charge neutrality, and inertness of the helium atoms makes helium microscopy an attractive candidate for the imaging of a range of samples. The simplest neutral helium microscope is the so-called pinhole microscope. It consists of a supersonic expansion helium beam collimated by two consecutive apertures (skimmer and pinhole), which together determine the beam spot size and hence the resolution at a given working distance to the sample. Due to the high ionization potential of neutral helium atoms, it is difficult to build efficient helium detectors. Therefore, it is crucial to optimize the microscope design to maximize the intensity for a given resolution and working distance. Here we present an optimization model for the helium pinhole microscope system. We show that for a given resolution and working distance, there is a single intensity maximum. Further we show that with present-day state-of-the-art detector technology (ionization efficiency 1 ×10-3 ), a resolution of the order of 600 nm at a working distance of 3 mm is possible. In order to make this quantification, we have assumed a Lambertian reflecting surface and calculated the beam spot size that gives a signal 100 cts/s within a solid angle of 0.02 π sr, following an existing design. Reducing the working distance to the micron range leads to an improved resolution of around 40 nm.

  20. Biofilm Formation in Microscopic Double Emulsion Droplets

    NASA Astrophysics Data System (ADS)

    Chang, Connie; Weitz, David

    2012-02-01

    In natural, medical, and industrial settings, there exist surface-associated communities of bacteria known as biofilms. These highly structured films are composed of bacterial cells embedded within self-produced extracellular matrix, usually composed of exopolysaccharides, proteins, and nucleic acids; this matrix serves to protect the bacterial community from antibiotics and environmental stressors. Here, we form biofilms encapsulated within monodisperse, microscopically-sized double emulsion droplets using microfluidics. The bacteria self-organize at the inner liquid-liquid droplet interfaces, multiply, and differentiate into extracellular matrix-producing cells, forming manifold three-dimensional shell-within-a-shell structures of biofilms, templated upon the inner core of spherical liquid droplets. By using microfluidics to encapsulate bacterial cells, we have the ability to view individual cells multiplying in microscopically-sized droplets, which allows for high-throughput analysis in studying the genetic program leading to biofilm development, or cell signaling that induces differentiation.

  1. Femtosecond scanning tunneling microscope

    SciTech Connect

    Taylor, A.J.; Donati, G.P.; Rodriguez, G.; Gosnell, T.R.; Trugman, S.A.; Some, D.I.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). By combining scanning tunneling microscopy with ultrafast optical techniques we have developed a novel tool to probe phenomena on atomic time and length scales. We have built and characterized an ultrafast scanning tunneling microscope in terms of temporal resolution, sensitivity and dynamic range. Using a novel photoconductive low-temperature-grown GaAs tip, we have achieved a temporal resolution of 1.5 picoseconds and a spatial resolution of 10 nanometers. This scanning tunneling microscope has both cryogenic and ultra-high vacuum capabilities, enabling the study of a wide range of important scientific problems.

  2. Ion photon emission microscope

    DOEpatents

    Doyle, Barney L.

    2003-04-22

    An ion beam analysis system that creates microscopic multidimensional image maps of the effects of high energy ions from an unfocussed source upon a sample by correlating the exact entry point of an ion into a sample by projection imaging of the ion-induced photons emitted at that point with a signal from a detector that measures the interaction of that ion within the sample. The emitted photons are collected in the lens system of a conventional optical microscope, and projected on the image plane of a high resolution single photon position sensitive detector. Position signals from this photon detector are then correlated in time with electrical effects, including the malfunction of digital circuits, detected within the sample that were caused by the individual ion that created these photons initially.

  3. Electron microscope aperture system

    NASA Technical Reports Server (NTRS)

    Heinemann, K. (Inventor)

    1976-01-01

    An electron microscope including an electron source, a condenser lens having either a circular aperture for focusing a solid cone of electrons onto a specimen or an annular aperture for focusing a hollow cone of electrons onto the specimen, and an objective lens having an annular objective aperture, for focusing electrons passing through the specimen onto an image plane are described. The invention also entails a method of making the annular objective aperture using electron imaging, electrolytic deposition and ion etching techniques.

  4. Microscopic enteritis: Bucharest consensus.

    PubMed

    Rostami, Kamran; Aldulaimi, David; Holmes, Geoffrey; Johnson, Matt W; Robert, Marie; Srivastava, Amitabh; Fléjou, Jean-François; Sanders, David S; Volta, Umberto; Derakhshan, Mohammad H; Going, James J; Becheanu, Gabriel; Catassi, Carlo; Danciu, Mihai; Materacki, Luke; Ghafarzadegan, Kamran; Ishaq, Sauid; Rostami-Nejad, Mohammad; Peña, A Salvador; Bassotti, Gabrio; Marsh, Michael N; Villanacci, Vincenzo

    2015-03-07

    Microscopic enteritis (ME) is an inflammatory condition of the small bowel that leads to gastrointestinal symptoms, nutrient and micronutrient deficiency. It is characterised by microscopic or sub-microscopic abnormalities such as microvillus changes and enterocytic alterations in the absence of definite macroscopic changes using standard modern endoscopy. This work recognises a need to characterize disorders with microscopic and submicroscopic features, currently regarded as functional or non-specific entities, to obtain further understanding of their clinical relevance. The consensus working party reviewed statements about the aetiology, diagnosis and symptoms associated with ME and proposes an algorithm for its investigation and treatment. Following the 5(th) International Course in Digestive Pathology in Bucharest in November 2012, an international group of 21 interested pathologists and gastroenterologists formed a working party with a view to formulating a consensus statement on ME. A five-step agreement scale (from strong agreement to strong disagreement) was used to score 21 statements, independently. There was strong agreement on all statements about ME histology (95%-100%). Statements concerning diagnosis achieved 85% to 100% agreement. A statement on the management of ME elicited agreement from the lowest rate (60%) up to 100%. The remaining two categories showed general agreement between experts on clinical presentation (75%-95%) and pathogenesis (80%-90%) of ME. There was strong agreement on the histological definition of ME. Weaker agreement on management indicates a need for further investigations, better definitions and clinical trials to produce quality guidelines for management. This ME consensus is a step toward greater recognition of a significant entity affecting symptomatic patients previously labelled as non-specific or functional enteropathy.

  5. Microscopic enteritis: Bucharest consensus

    PubMed Central

    Rostami, Kamran; Aldulaimi, David; Holmes, Geoffrey; Johnson, Matt W; Robert, Marie; Srivastava, Amitabh; Fléjou, Jean-François; Sanders, David S; Volta, Umberto; Derakhshan, Mohammad H; Going, James J; Becheanu, Gabriel; Catassi, Carlo; Danciu, Mihai; Materacki, Luke; Ghafarzadegan, Kamran; Ishaq, Sauid; Rostami-Nejad, Mohammad; Peña, A Salvador; Bassotti, Gabrio; Marsh, Michael N; Villanacci, Vincenzo

    2015-01-01

    Microscopic enteritis (ME) is an inflammatory condition of the small bowel that leads to gastrointestinal symptoms, nutrient and micronutrient deficiency. It is characterised by microscopic or sub-microscopic abnormalities such as microvillus changes and enterocytic alterations in the absence of definite macroscopic changes using standard modern endoscopy. This work recognises a need to characterize disorders with microscopic and submicroscopic features, currently regarded as functional or non-specific entities, to obtain further understanding of their clinical relevance. The consensus working party reviewed statements about the aetiology, diagnosis and symptoms associated with ME and proposes an algorithm for its investigation and treatment. Following the 5th International Course in Digestive Pathology in Bucharest in November 2012, an international group of 21 interested pathologists and gastroenterologists formed a working party with a view to formulating a consensus statement on ME. A five-step agreement scale (from strong agreement to strong disagreement) was used to score 21 statements, independently. There was strong agreement on all statements about ME histology (95%-100%). Statements concerning diagnosis achieved 85% to 100% agreement. A statement on the management of ME elicited agreement from the lowest rate (60%) up to 100%. The remaining two categories showed general agreement between experts on clinical presentation (75%-95%) and pathogenesis (80%-90%) of ME. There was strong agreement on the histological definition of ME. Weaker agreement on management indicates a need for further investigations, better definitions and clinical trials to produce quality guidelines for management. This ME consensus is a step toward greater recognition of a significant entity affecting symptomatic patients previously labelled as non-specific or functional enteropathy. PMID:25759526

  6. Microscopic Image Inside 'Endurance'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This magnified view of a rock surface inside 'Endurance Crater' combines four frames taken by the microscopic imager on NASA's Mars Exploration Rover Opportunity during the rover's 142nd martian day, or sol, on June 17, 2004. This patch of rock is in a region of contact between a layer of rock corresponding to bedrock that Opportunity examined earlier at 'Eagle Crater' and the next-lower layer. The area imaged is about 6 centimeters (2.4 inches) on each side.

  7. Thermal Lens Microscope

    NASA Astrophysics Data System (ADS)

    Uchiyama, Kenji; Hibara, Akihide; Kimura, Hiroko; Sawada, Tsuguo; Kitamori, Takehiko

    2000-09-01

    We developed a novel laser microscope based on the thermal lens effect induced by a coaxial beam comprised of excitation and probe beams. The signal generation mechanism was confirmed to be an authentic thermal lens effect from the measurement of signal and phase dependences on optical configurations between the sample and the probe beam focus, and therefore, the thermal lens effect theory could be applied. Two-point spatial resolution was determined by the spot size of the excitation beam, not by the thermal diffusion length. Sensitivity was quite high, and the detection ability, evaluated using a submicron microparticle containing dye molecules, was 0.8 zmol/μm2, hence a distribution image of trace chemical species could be obtained quantitatively. In addition, analytes are not restricted to fluorescent species, therefore, the thermal lens microscope is a promising analytical microscope. A two-dimensional image of a histamine molecule distribution, which was produced in mast cells at the femtomole level in a human nasal mucous polyp, was obtained.

  8. Thimble microscope system

    NASA Astrophysics Data System (ADS)

    Kamal, Tahseen; Rubinstein, Jaden; Watkins, Rachel; Cen, Zijian; Kong, Gary; Lee, W. M.

    2016-12-01

    Wearable computing devices, e.g. Google Glass, Smart watch, embodies the new human design frontier, where technology interfaces seamlessly with human gestures. During examination of any subject in the field (clinic, surgery, agriculture, field survey, water collection), our sensory peripherals (touch and vision) often go hand-in-hand. The sensitivity and maneuverability of the human fingers are guided with tight distribution of biological nerve cells, which perform fine motor manipulation over a range of complex surfaces that is often out of sight. Our sight (or naked vision), on the other hand, is generally restricted to line of sight that is ill-suited to view around corner. Hence, conventional imaging methods are often resort to complex light guide designs (periscope, endoscopes etc) to navigate over obstructed surfaces. Using modular design strategies, we constructed a prototype miniature microscope system that is incorporated onto a wearable fixture (thimble). This unique platform allows users to maneuver around a sample and take high resolution microscopic images. In this paper, we provide an exposition of methods to achieve a thimble microscopy; microscope lens fabrication, thimble design, integration of miniature camera and liquid crystal display.

  9. Reliability of Pressure Ulcer Rates: How Precisely Can We Differentiate Among Hospital Units, and Does the Standard Signal‐Noise Reliability Measure Reflect This Precision?

    PubMed Central

    Cramer, Emily

    2016-01-01

    Abstract Hospital performance reports often include rankings of unit pressure ulcer rates. Differentiating among units on the basis of quality requires reliable measurement. Our objectives were to describe and apply methods for assessing reliability of hospital‐acquired pressure ulcer rates and evaluate a standard signal‐noise reliability measure as an indicator of precision of differentiation among units. Quarterly pressure ulcer data from 8,199 critical care, step‐down, medical, surgical, and medical‐surgical nursing units from 1,299 US hospitals were analyzed. Using beta‐binomial models, we estimated between‐unit variability (signal) and within‐unit variability (noise) in annual unit pressure ulcer rates. Signal‐noise reliability was computed as the ratio of between‐unit variability to the total of between‐ and within‐unit variability. To assess precision of differentiation among units based on ranked pressure ulcer rates, we simulated data to estimate the probabilities of a unit's observed pressure ulcer rate rank in a given sample falling within five and ten percentiles of its true rank, and the probabilities of units with ulcer rates in the highest quartile and highest decile being identified as such. We assessed the signal‐noise measure as an indicator of differentiation precision by computing its correlations with these probabilities. Pressure ulcer rates based on a single year of quarterly or weekly prevalence surveys were too susceptible to noise to allow for precise differentiation among units, and signal‐noise reliability was a poor indicator of precision of differentiation. To ensure precise differentiation on the basis of true differences, alternative methods of assessing reliability should be applied to measures purported to differentiate among providers or units based on quality. © 2016 The Authors. Research in Nursing & Health published by Wiley Periodicals, Inc. PMID:27223598

  10. Reliability of Pressure Ulcer Rates: How Precisely Can We Differentiate Among Hospital Units, and Does the Standard Signal-Noise Reliability Measure Reflect This Precision?

    PubMed

    Staggs, Vincent S; Cramer, Emily

    2016-08-01

    Hospital performance reports often include rankings of unit pressure ulcer rates. Differentiating among units on the basis of quality requires reliable measurement. Our objectives were to describe and apply methods for assessing reliability of hospital-acquired pressure ulcer rates and evaluate a standard signal-noise reliability measure as an indicator of precision of differentiation among units. Quarterly pressure ulcer data from 8,199 critical care, step-down, medical, surgical, and medical-surgical nursing units from 1,299 US hospitals were analyzed. Using beta-binomial models, we estimated between-unit variability (signal) and within-unit variability (noise) in annual unit pressure ulcer rates. Signal-noise reliability was computed as the ratio of between-unit variability to the total of between- and within-unit variability. To assess precision of differentiation among units based on ranked pressure ulcer rates, we simulated data to estimate the probabilities of a unit's observed pressure ulcer rate rank in a given sample falling within five and ten percentiles of its true rank, and the probabilities of units with ulcer rates in the highest quartile and highest decile being identified as such. We assessed the signal-noise measure as an indicator of differentiation precision by computing its correlations with these probabilities. Pressure ulcer rates based on a single year of quarterly or weekly prevalence surveys were too susceptible to noise to allow for precise differentiation among units, and signal-noise reliability was a poor indicator of precision of differentiation. To ensure precise differentiation on the basis of true differences, alternative methods of assessing reliability should be applied to measures purported to differentiate among providers or units based on quality. © 2016 The Authors. Research in Nursing & Health published by Wiley Periodicals, Inc. © 2016 The Authors. Research in Nursing & Health published by Wiley Periodicals, Inc.

  11. Q: How do Microscopes Work?

    ERIC Educational Resources Information Center

    Zimov, Sarah

    2004-01-01

    Microscopes allow scientists to examine everyday objects in extraordinary ways. They provide high-resolution images that show objects in fine detail. This brief article describes the many types of microscopes and how they are used in different scientific venues.

  12. Q: How do Microscopes Work?

    ERIC Educational Resources Information Center

    Zimov, Sarah

    2004-01-01

    Microscopes allow scientists to examine everyday objects in extraordinary ways. They provide high-resolution images that show objects in fine detail. This brief article describes the many types of microscopes and how they are used in different scientific venues.

  13. Reflection Coefficients.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1994-01-01

    Discusses and provides an example of reflectivity approximation to determine whether reflection will occur. Provides a method to show thin-film interference on a projection screen. Also applies the reflectivity concepts to electromagnetic wave systems. (MVL)

  14. Reflection Coefficients.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1994-01-01

    Discusses and provides an example of reflectivity approximation to determine whether reflection will occur. Provides a method to show thin-film interference on a projection screen. Also applies the reflectivity concepts to electromagnetic wave systems. (MVL)

  15. Light Microscopy Microscope Experiment

    NASA Image and Video Library

    2016-02-04

    Ground testing for the first confocal Light Microscopy Microscope (LMM) Experiment. Procter and Gamble is working with NASA Glenn scientists to prepare for a study that examines product stabilizers in a microgravity environment. The particles in the tube glow orange because they have been fluorescently tagged with a dye that reacts to green laser lights to allow construction of a 3D image point by point. The experiment, which will be sent to the ISS later this year, will help P&G develop improved product stabilizers to extend shelf life and develop more environmentally friendly packaging.

  16. Nanosecond electron microscopes

    PubMed

    Bostanjoglo; Elschner; Mao; Nink; Weingartner

    2000-04-01

    Combining electron optics, fast electronics and pulsed lasers, a transmission and a photoelectron emission microscope were built, which visualize events in thin films and on surfaces with a time resolution of several nanoseconds. The high-speed electron microscopy is capable to track fast laser-induced processes in metals below the ablation threshold, which are difficult to detect by other imaging techniques. The material response to nano- and femtosecond laser pulses was found to be very different. It was dominated by thermo/chemocapillary flow and chemical reactions in the case of nanosecond pulses, and by mechanical deformations and non-thermal electron emission after a femtosecond pulse.

  17. Atomic Force Microscope

    SciTech Connect

    Day, R.D.; Russell, P.E.

    1988-12-01

    The Atomic Force Microscope (AFM) is a recently developed instrument that has achieved atomic resolution imaging of both conducting and non- conducting surfaces. Because the AFM is in the early stages of development, and because of the difficulty of building the instrument, it is currently in use in fewer than ten laboratories worldwide. It promises to be a valuable tool for obtaining information about engineering surfaces and aiding the .study of precision fabrication processes. This paper gives an overview of AFM technology and presents plans to build an instrument designed to look at engineering surfaces.

  18. Adirondack Under the Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image was taken by the Mars Exploration Rover Spirit front hazard-identification camera after the rover's first post-egress drive on Mars Sunday, Jan. 15, 2004. Engineers drove the rover approximately 3 meters (10 feet) from the Columbia Memorial Station toward the first rock target, seen in the foreground. The football-sized rock was dubbed Adirondack because of its mountain-shaped appearance. Scientists have begun using the microscopic imager instrument at the end of the rover's robotic arm to examine the rock and understand how it formed.

  19. Adirondack Under the Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image was taken by the Mars Exploration Rover Spirit front hazard-identification camera after the rover's first post-egress drive on Mars Sunday, Jan. 15, 2004. Engineers drove the rover approximately 3 meters (10 feet) from the Columbia Memorial Station toward the first rock target, seen in the foreground. The football-sized rock was dubbed Adirondack because of its mountain-shaped appearance. Scientists have begun using the microscopic imager instrument at the end of the rover's robotic arm to examine the rock and understand how it formed.

  20. Solid state optical microscope

    DOEpatents

    Young, I.T.

    1983-08-09

    A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal. 2 figs.

  1. Solid state optical microscope

    DOEpatents

    Young, Ian T.

    1983-01-01

    A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

  2. [Microscopic infrared spectral imaging of oily core].

    PubMed

    Huang, Qiao-Song; Yu, Zhao-Xian; Li, Jing; Chen, Chen

    2009-02-01

    In the present paper, the authors examined some oily core by microscopic infrared spectral imaging methods. Those methods can be classified in three modes, referred to as "transmission mode", "reflection mode" and "attenuated total reflection (ATR) mode". The observed oily core samples belong to siltstone. The samples were made of quartz (-20%), feldspar(-50%) and other rock (igneous rock 25%, metamorphic rocks 1%, sedimentary rock 4%); a little recrystallized calcite (-1%) was in the pore, and the argillaceous matter was distributed along the edge of a pore. The experimental work has been accomplished using SHIMADZU Model IRPrestige-21 Fourier transform infrared spectrophotometer plus AIM8800 infrared microscope. For IRPrestige-21, the spectral range is 7 800-350 cm(-1) spectral resolution is 1 cm(-1), and AIM8800 microscope with motorized stages has a resolution of 1 micrometer. The experiment was preformed at room temperature. In "transmission mode" infrared spectral imaging method, the spectral range was limited in wavenumbers greater than 2 000 cm(-1) because the base glass piece has strong light absorption. In contrast with "transmission mode", in "attenuated total reflection (ATR) mode", the depth of penetration into sample is very small (1-2 micrometer), then the absorbance value has nothing to do with base glass piece light absorption. In microscopic infrared transmission spectra, the experimental result shows that there are some strong absorption peaks at 2 866, 2 928, 3 618 and 2 515 cm(-1) respectively. The former two peaks correspond to methyl(methylene) symmetrical and unsymmetrical stretch vibration mode, respectively. The latter two peaks correspond to hydroxyl-stretch vibration mode and S-H, P-H chemical bond stretch vibration mode, respectively. In microscopic longwave infrared ATR spectra, there are other stronger absorption peaks at 1 400, 1 038 and 783 cm(i1)respectively, corresponding to methyl(methylene) widing vibration mode and optical mode

  3. Microscopic Tribotactic Walkers

    NASA Astrophysics Data System (ADS)

    Steimel, Joshua; Aragones, Juan; Alexander-Katz, Alfredo

    2014-03-01

    The translational motion of a rotating object near a surface is strongly dependent on the friction between the object and the surface. The process of friction is inherently directional and the friction coefficient can be anisotropic even in the absence of a net friction coefficient gradient. This is macroscopically observed in the ordering motif of some animal hair or scales and a microscopic analog can be imagined where the friction coefficient is determined by the strength and density of reversible bonds between a rotating object and the substrate. For high friction coefficients most of the rotational motion is converted into translational motion; conversely for low friction coefficients the object primarily rotates in place. We exploited this property to design and test a new class of motile system that displays tribotaxis, which is the process by which an object detects differences in the local friction coefficient and moves accordingly either to regions of higher or lower friction. These synthetic tribotactic microscopic walkers, composed of a pair of functionalized superparamagnetic beads, detect gradients in the spatial friction coefficient and migrate towards high friction areas when actuated in a random fashion. The effective friction between the walkers and the substrate is controlled by the local density of active receptors in the substrate. The tribotactic walkers also displayed trapping in high friction areas where the density of free receptors is higher.

  4. Electron microscope phase enhancement

    DOEpatents

    Jin, Jian; Glaeser, Robert M.

    2010-06-15

    A microfabricated electron phase shift element is used for modifying the phase characteristics of an electron beam passing though its center aperture, while not affecting the more divergent portion of an incident beam to selectively provide a ninety-degree phase shift to the unscattered beam in the back focal plan of the objective lens, in order to realize Zernike-type, in-focus phase contrast in an electron microscope. One application of the element is to increase the contrast of an electron microscope for viewing weakly scattering samples while in focus. Typical weakly scattering samples include biological samples such as macromolecules, or perhaps cells. Preliminary experimental images demonstrate that these devices do apply a ninety degree phase shift as expected. Electrostatic calculations have been used to determine that fringing fields in the region of the scattered electron beams will cause a negligible phase shift as long as the ratio of electrode length to the transverse feature-size aperture is about 5:1. Calculations are underway to determine the feasibility of aspect smaller aspect ratios of about 3:1 and about 2:1.

  5. Microscopic Rayleigh Droplet Beams

    NASA Astrophysics Data System (ADS)

    Doak, R. B.

    2005-11-01

    A periodically triggered Rayleigh Droplet Beam (RDB) delivers a perfectly linear and periodic stream of identical, monoenergetic droplets that are phase-locked to the trigger signal. The droplet diameter and spacing are easily adjusted of choice of nozzle diameter and trigger frequency. Any liquid of low viscosity may be emloyed as the beam fluid. Although the field of nanofluidics is expanding rapidly, little effort has yet been devoted to ``external flows'' such as RDB's. At ASU we have generated RDB's of water and methanol down to 2 microns in droplet diameter. Nozzle clogging is the sole impediment to smaller droplets. Microscopic Rayleigh droplet beams offer tremendous potential for fundamental physical measurements, fluid dynamics research, and nanofabrication. This talk will describe the apparatus and techniques used at ASU to generate RDB's (surprisingly simple and inexpensive), discuss the triboelectric phenomena that play a role (surprisingly significant), present some initial experimental fluid dynamics measurements, and briefly survey RDB applications. Our particular interest in RDB's is as microscopic transport systems to deliver hydrated, undenatured proteins into vacuum for structure determination via serial diffraction of x-rays or electrons. This may offer the first general method for structure determination of non-crystallizable proteins.

  6. Quantification of the Information Limit of Transmission Electron Microscopes

    SciTech Connect

    Barthel, J.; Thust, A.

    2008-11-14

    The resolving power of high-resolution transmission electron microscopes is characterized by the information limit, which reflects the size of the smallest object detail observable with a particular instrument. We introduce a highly accurate measurement method for the information limit, which is suitable for modern aberration-corrected electron microscopes. An experimental comparison with the traditionally applied Young's fringe method yields severe discrepancies and confirms theoretical considerations according to which the Young's fringe method does not reveal the information limit.

  7. Research and application of ergonomics to optical microscope

    NASA Astrophysics Data System (ADS)

    Jiang, Xue-kun; Xiao, Ze-xin; Zhang, Jie

    2008-03-01

    The characteristics of the human and the microscope, and their integrated characteristic have been studied respectively in this paper. Our results indicated that the correspondence of (i) focusing installment with human body arm, (ii) the height of ocular with eyes, (iii) visual characteristic with illuminative condition of the optical microscope, should obey the theory of the ergonomics. This was reflected in the structural design and the produce of the product, and therefore, improved the property of the amenity of the machine.

  8. Anisotropic contrast optical microscope

    NASA Astrophysics Data System (ADS)

    Peev, D.; Hofmann, T.; Kananizadeh, N.; Beeram, S.; Rodriguez, E.; Wimer, S.; Rodenhausen, K. B.; Herzinger, C. M.; Kasputis, T.; Pfaunmiller, E.; Nguyen, A.; Korlacki, R.; Pannier, A.; Li, Y.; Schubert, E.; Hage, D.; Schubert, M.

    2016-11-01

    An optical microscope is described that reveals contrast in the Mueller matrix images of a thin, transparent, or semi-transparent specimen located within an anisotropic object plane (anisotropic filter). The specimen changes the anisotropy of the filter and thereby produces contrast within the Mueller matrix images. Here we use an anisotropic filter composed of a semi-transparent, nanostructured thin film with sub-wavelength thickness placed within the object plane. The sample is illuminated as in common optical microscopy but the light is modulated in its polarization using combinations of linear polarizers and phase plate (compensator) to control and analyze the state of polarization. Direct generalized ellipsometry data analysis approaches permit extraction of fundamental Mueller matrix object plane images dispensing with the need of Fourier expansion methods. Generalized ellipsometry model approaches are used for quantitative image analyses. These images are obtained from sets of multiple images obtained under various polarizer, analyzer, and compensator settings. Up to 16 independent Mueller matrix images can be obtained, while our current setup is limited to 11 images normalized by the unpolarized intensity. We demonstrate the anisotropic contrast optical microscope by measuring lithographically defined micro-patterned anisotropic filters, and we quantify the adsorption of an organic self-assembled monolayer film onto the anisotropic filter. Comparison with an isotropic glass slide demonstrates the image enhancement obtained by our method over microscopy without the use of an anisotropic filter. In our current instrument, we estimate the limit of detection for organic volumetric mass within the object plane of ≈49 fg within ≈7 × 7 μm2 object surface area. Compared to a quartz crystal microbalance with dissipation instrumentation, where contemporary limits require a total load of ≈500 pg for detection, the instrumentation demonstrated here improves

  9. Anisotropic contrast optical microscope.

    PubMed

    Peev, D; Hofmann, T; Kananizadeh, N; Beeram, S; Rodriguez, E; Wimer, S; Rodenhausen, K B; Herzinger, C M; Kasputis, T; Pfaunmiller, E; Nguyen, A; Korlacki, R; Pannier, A; Li, Y; Schubert, E; Hage, D; Schubert, M

    2016-11-01

    An optical microscope is described that reveals contrast in the Mueller matrix images of a thin, transparent, or semi-transparent specimen located within an anisotropic object plane (anisotropic filter). The specimen changes the anisotropy of the filter and thereby produces contrast within the Mueller matrix images. Here we use an anisotropic filter composed of a semi-transparent, nanostructured thin film with sub-wavelength thickness placed within the object plane. The sample is illuminated as in common optical microscopy but the light is modulated in its polarization using combinations of linear polarizers and phase plate (compensator) to control and analyze the state of polarization. Direct generalized ellipsometry data analysis approaches permit extraction of fundamental Mueller matrix object plane images dispensing with the need of Fourier expansion methods. Generalized ellipsometry model approaches are used for quantitative image analyses. These images are obtained from sets of multiple images obtained under various polarizer, analyzer, and compensator settings. Up to 16 independent Mueller matrix images can be obtained, while our current setup is limited to 11 images normalized by the unpolarized intensity. We demonstrate the anisotropic contrast optical microscope by measuring lithographically defined micro-patterned anisotropic filters, and we quantify the adsorption of an organic self-assembled monolayer film onto the anisotropic filter. Comparison with an isotropic glass slide demonstrates the image enhancement obtained by our method over microscopy without the use of an anisotropic filter. In our current instrument, we estimate the limit of detection for organic volumetric mass within the object plane of ≈49 fg within ≈7 × 7 μm(2) object surface area. Compared to a quartz crystal microbalance with dissipation instrumentation, where contemporary limits require a total load of ≈500 pg for detection, the instrumentation demonstrated here improves

  10. Mars Under the Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This magnified look at the martian soil near the Mars Exploration Rover Opportunity's landing site, Meridiani Planum, shows coarse grains sprinkled over a fine layer of sand. The image was captured by the rover's microscopic imager on the 10th day, or sol, of its mission. Scientists are intrigued by the spherical rocks, which can be formed by a variety of geologic processes, including cooling of molten lava droplets and accretion of concentric layers of material around a particle or 'seed.'

    The examined patch of soil is 3 centimeters (1.2 inches) across. The circular grain in the lower left corner is approximately 3 millimeters (.12 inches) across, or about the size of a sunflower seed.

  11. Imaging arrangement and microscope

    SciTech Connect

    Pertsinidis, Alexandros; Chu, Steven

    2015-12-15

    An embodiment of the present invention is an imaging arrangement that includes imaging optics, a fiducial light source, and a control system. In operation, the imaging optics separate light into first and second tight by wavelength and project the first and second light onto first and second areas within first and second detector regions, respectively. The imaging optics separate fiducial light from the fiducial light source into first and second fiducial light and project the first and second fiducial light onto third and fourth areas within the first and second detector regions, respectively. The control system adjusts alignment of the imaging optics so that the first and second fiducial light projected onto the first and second detector regions maintain relatively constant positions within the first and second detector regions, respectively. Another embodiment of the present invention is a microscope that includes the imaging arrangement.

  12. Visualizing the Microscopic World.

    PubMed

    Cerqueira, Nuno M F S A; Fernandes, Pedro A; Ramos, Maria João

    2017-08-09

    Visualization can be a motivating way of teaching students about the microscopic world. This can become even more exciting if the information is based on accurate computational results rather than on crude approximations that eventually might create unreal alternative perceptions. Here, we report on a VMD plug-in, named vmdMagazine, which can turn computational simulations into stunning high-impact video presentations, suitable for classes/lectures and even conferences. The software will help students/audience to understand atoms and molecules better and learn to like them. The present paper is meant to give a general idea of the software's potential, showing how it works and how it can be used for educational purposes. The software is freely available at: http://www.fc.up.pt/PortoBioComp/database/doku.php?id=vmdmagazine .

  13. Design and analysis of soft X-ray imaging microscopes

    NASA Technical Reports Server (NTRS)

    Shealy, David L.; Cheng, Wang; Wu, Jiang; Hoover, Richard B.

    1992-01-01

    The spherical Schwarzschild microscope for soft X-ray applications in microscopy and projection lithography consists of two concentric spherical mirrors configured such that the third-order spherical aberration and coma are zero. Since multilayers are used on the mirror substrates for X-ray applications, it is desirable to have only two reflecting surfaces in a microscope. To reduce microscope aberrations and increase the field of view, generalized mirror surface profiles are here considered. Based on incoherent and sine wave modulation transfer function calculations, the object plane resolution of a microscope has been analyzed as a function of the object height and numerical aperture (NA) of the primary for several spherical Schwarzschild, conic, and aspherical Head reflecting two-mirror microscope configurations. The Head microscope with a NA of 0.4 achieves diffraction limited performance for objects with a diameter of 40 microns. Thus, it seems possible to record images with a feature size less than 100 A with a 40x microscope when using 40 A radiation.

  14. Fermi Gas Microscope

    NASA Astrophysics Data System (ADS)

    Setiawan, Widagdo

    Recent advances in using microscopes in ultracold atom experiment have allowed experimenters for the first time to directly observe and manipulate individual atoms in individual lattice sites. This technique enhances our capability to simulate strongly correlated systems such as Mott insulator and high temperature superconductivity. Currently, all ultracold atom experiments with high resolution imaging capability use bosonic atoms. In this thesis, I present our progress towards creating the fermionic version of the microscope experiment which is more suitable for simulating real condensed matter systems. Lithium is ideal due to the existence of both fermionic and bosonic isotopes, its light mass, which means faster experiment time scales that suppresses many sources of technical noise, and also due to the existence of a broad Feshbach resonance, which can be used to tune the inter-particle interaction strength over a wide range from attractive, non-interacting, and repulsive interactions. A high numerical aperture objective will be used to image and manipulate the atoms with single lattice site resolution. This setup should allow us to implement the Hubbard hamiltonian which could describe interesting quantum phases such as antiferromagnetism, d-wave superfluidity, and high temperature superconductivity. I will also discuss the feasibility of the Raman sideband cooling method for cooling the atoms during the imaging process. We have also developed a new electronic control system to control the sequence of the experiment. This electronic system is very scalable in order to keep up with the increasing complexity of atomic physics experiments. Furthermore, the system is also designed to be more precise in order to keep up with the faster time scale of lithium experiment.

  15. Atomic Force Microscope Operation

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on image for animation (large file)

    This animation is a scientific illustration of the operation of NASA's Phoenix Mars Lander's Atomic Force Microscope, or AFM. The AFM is part of Phoenix's Microscopy, Electrochemistry, and Conductivity Analyzer, or MECA.

    The AFM is used to image the smallest Martian particles using a very sharp tip at the end of one of eight beams.

    The beam of the AFM is set into vibration and brought up to the surface of a micromachined silicon substrate. The substrate has etched in it a series of pits, 5 micrometers deep, designed to hold the Martian dust particles.

    The microscope then maps the shape of particles in three dimensions by scanning them with the tip.

    At the end of the animation is a 3D representation of the AFM image of a particle that was part of a sample informally called 'Sorceress.' The sample was delivered to the AFM on the 38th Martian day, or sol, of the mission (July 2, 2008).

    The image shows four round pits, only 5 microns in depth, that were micromachined into the silicon substrate.

    A Martian particle only one micrometer, or one millionth of a meter, across is held in the upper left pit.

    The rounded particle shown at the highest magnification ever seen from another world is a particle of the dust that cloaks Mars. Such dust particles color the Martian sky pink, feed storms that regularly envelop the planet and produce Mars' distinctive red soil.

    The AFM was developed by a Swiss-led consortium, with Imperial College London producing the silicon substrate that holds sampled particles.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  16. Ultra high frequency imaging acoustic microscope

    DOEpatents

    Deason, Vance A.; Telschow, Kenneth L.

    2006-05-23

    An imaging system includes: an object wavefront source and an optical microscope objective all positioned to direct an object wavefront onto an area of a vibrating subject surface encompassed by a field of view of the microscope objective, and to direct a modulated object wavefront reflected from the encompassed surface area through a photorefractive material; and a reference wavefront source and at least one phase modulator all positioned to direct a reference wavefront through the phase modulator and to direct a modulated reference wavefront from the phase modulator through the photorefractive material to interfere with the modulated object wavefront. The photorefractive material has a composition and a position such that interference of the modulated object wavefront and modulated reference wavefront occurs within the photorefractive material, providing a full-field, real-time image signal of the encompassed surface area.

  17. Trace metal determination by total-reflection X-ray fluorescence (TXRF) for the differentiation between pure fuel oil (bunker oil) and waste oil (sludge) in maritime shipping legal cases

    NASA Astrophysics Data System (ADS)

    Schirmacher, Martina; Freimann, Peter; Schmidt, Diether; Dahlmann, Gerhard

    1993-02-01

    Using a simple sample preparation technique, the concentrations of Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn and Pb in several bunker and sludge oils have been measured simultaneously by total-reflection X-ray fluorescence analysis (TXRF) in the mg/kg range. As a result, five elements are suitable in distinguishing between both types of oil: Ca, V, Fe, Ni and Zn. This differentiation can be used in cases where shipping vessel captains or chiefs attempt to conceal illegal waste oil discharge at sea by wrongly declaring bunker oil as sludge.

  18. High sensitive reflection type long period fiber grating biosensor for real time detection of thyroglobulin, a differentiated thyroid cancer biomarker: the Smart Health project

    NASA Astrophysics Data System (ADS)

    Quero, G.; Severino, R.; Vaiano, P.; Consales, M.; Ruvo, M.; Sandomenico, A.; Borriello, A.; Giordano, M.; Zuppolini, S.; Diodato, L.; Cutolo, A.; Cusano, A.

    2015-09-01

    We report the development of a reflection-type long period fiber grating (LPG) biosensor able to perform the real time detection of thyroid cancer markers in the needle washout of fine-needle aspiration biopsy. A standard LPG is first transformed in a practical probe working in reflection mode, then it is coated by an atactic-polystyrene overlay in order to increase its surrounding refractive index sensitivity and to provide, at the same time, the desired interfacial properties for a stable bioreceptor immobilization. The results provide a clear demonstration of the effectiveness and sensitivity of the developed biosensing platform, allowing the in vitro detection of human Thyroglobulin at sub-nanomolar concentrations.

  19. No departure to "Pandora"? Using critical phenomenology to differentiate "naive" from "reflective" experience in psychiatry and psychosomatic medicine (A comment on Schwartz and Wiggins, 2010)

    PubMed Central

    2010-01-01

    The mind-body problem lies at the heart of the clinical practice of both psychiatry and psychosomatic medicine. In their recent publication, Schwartz and Wiggins address the question of how to understand life as central to the mind-body problem. Drawing on their own use of the phenomenological method, we propose that the mind-body problem is not resolved by a general, evocative appeal to an all encompassing life-concept, but rather falters precisely at the insurmountable difference between "natural" and a "reflective" experience built into phenomenological method itself. Drawing on the works of phenomenologically oriented thinkers, we describe life as inherently "teleological" without collapsing life with our subjective perspective, or stepping over our epistemological limits. From the phenomenology it can be demonstrated that the hypothetical teleological qualities are a reflective reconstruction modelled on human behavioural structure. PMID:21040525

  20. No departure to "Pandora"? Using critical phenomenology to differentiate "naive" from "reflective" experience in psychiatry and psychosomatic medicine (a comment on Schwartz and Wiggins, 2010).

    PubMed

    Schlimme, Jann E; Bonnemann, Catharina; Mishara, Aaron L

    2010-10-31

    The mind-body problem lies at the heart of the clinical practice of both psychiatry and psychosomatic medicine. In their recent publication, Schwartz and Wiggins address the question of how to understand life as central to the mind-body problem. Drawing on their own use of the phenomenological method, we propose that the mind-body problem is not resolved by a general, evocative appeal to an all encompassing life-concept, but rather falters precisely at the insurmountable difference between "natural" and a "reflective" experience built into phenomenological method itself. Drawing on the works of phenomenologically oriented thinkers, we describe life as inherently "teleological" without collapsing life with our subjective perspective, or stepping over our epistemological limits. From the phenomenology it can be demonstrated that the hypothetical teleological qualities are a reflective reconstruction modelled on human behavioural structure.

  1. Isotope analysis in the transmission electron microscope.

    PubMed

    Susi, Toma; Hofer, Christoph; Argentero, Giacomo; Leuthner, Gregor T; Pennycook, Timothy J; Mangler, Clemens; Meyer, Jannik C; Kotakoski, Jani

    2016-10-10

    The Ångström-sized probe of the scanning transmission electron microscope can visualize and collect spectra from single atoms. This can unambiguously resolve the chemical structure of materials, but not their isotopic composition. Here we differentiate between two isotopes of the same element by quantifying how likely the energetic imaging electrons are to eject atoms. First, we measure the displacement probability in graphene grown from either (12)C or (13)C and describe the process using a quantum mechanical model of lattice vibrations coupled with density functional theory simulations. We then test our spatial resolution in a mixed sample by ejecting individual atoms from nanoscale areas spanning an interface region that is far from atomically sharp, mapping the isotope concentration with a precision better than 20%. Although we use a scanning instrument, our method may be applicable to any atomic resolution transmission electron microscope and to other low-dimensional materials.

  2. Servo-controlled intravital microscope system

    NASA Technical Reports Server (NTRS)

    Mansour, M. N.; Wayland, H. J.; Chapman, C. P. (Inventor)

    1975-01-01

    A microscope system is described for viewing an area of a living body tissue that is rapidly moving, by maintaining the same area in the field-of-view and in focus. A focus sensing portion of the system includes two video cameras at which the viewed image is projected, one camera being slightly in front of the image plane and the other slightly behind it. A focus sensing circuit for each camera differentiates certain high frequency components of the video signal and then detects them and passes them through a low pass filter, to provide dc focus signal whose magnitudes represent the degree of focus. An error signal equal to the difference between the focus signals, drives a servo that moves the microscope objective so that an in-focus view is delivered to an image viewing/recording camera.

  3. Isotope analysis in the transmission electron microscope

    PubMed Central

    Susi, Toma; Hofer, Christoph; Argentero, Giacomo; Leuthner, Gregor T.; Pennycook, Timothy J.; Mangler, Clemens; Meyer, Jannik C.; Kotakoski, Jani

    2016-01-01

    The Ångström-sized probe of the scanning transmission electron microscope can visualize and collect spectra from single atoms. This can unambiguously resolve the chemical structure of materials, but not their isotopic composition. Here we differentiate between two isotopes of the same element by quantifying how likely the energetic imaging electrons are to eject atoms. First, we measure the displacement probability in graphene grown from either 12C or 13C and describe the process using a quantum mechanical model of lattice vibrations coupled with density functional theory simulations. We then test our spatial resolution in a mixed sample by ejecting individual atoms from nanoscale areas spanning an interface region that is far from atomically sharp, mapping the isotope concentration with a precision better than 20%. Although we use a scanning instrument, our method may be applicable to any atomic resolution transmission electron microscope and to other low-dimensional materials. PMID:27721420

  4. Interference reflection microscopy.

    PubMed

    Barr, Valarie A; Bunnell, Stephen C

    2009-12-01

    Interference reflection microscopy (IRM) is an optical technique used to study cell adhesion or cell mobility on a glass coverslip. The interference of reflected light waves generates images with high contrast and definition. IRM can be used to examine almost any cell that will rest upon a glass surface, although it is most useful in examining sites of close contact between a cell and substratum. This unit presents methods for obtaining IRM images of cells with particular emphasis on IRM imaging with a laser scanning confocal microscope (LSCM), as most LSCM are already capable of recording these images without any modification of the instrument. Techniques are presented for imaging fixed and live cells, as well as simultaneous multi-channel capture of fluorescence and reflection images. Copyright 2009 by John Wiley & Sons, Inc.

  5. The Reflective Learning Continuum: Reflecting on Reflection

    ERIC Educational Resources Information Center

    Peltier, James W.; Hay, Amanda; Drago, William

    2005-01-01

    The importance of reflection to marketing educators is increasingly recognized. However, there is a lack of empirical research that considers reflection within the context of both the marketing and general business education literature. This article describes the use of an instrument that can be used to measure four identified levels of a…

  6. The Reflective Learning Continuum: Reflecting on Reflection

    ERIC Educational Resources Information Center

    Peltier, James W.; Hay, Amanda; Drago, William

    2005-01-01

    The importance of reflection to marketing educators is increasingly recognized. However, there is a lack of empirical research that considers reflection within the context of both the marketing and general business education literature. This article describes the use of an instrument that can be used to measure four identified levels of a…

  7. Differentiation potential of human postnatal mesenchymal stem cells, mesoangioblasts, and multipotent adult progenitor cells reflected in their transcriptome and partially influenced by the culture conditions.

    PubMed

    Roobrouck, Valerie D; Clavel, Carlos; Jacobs, Sandra A; Ulloa-Montoya, Fernando; Crippa, Stefania; Sohni, Abhishek; Roberts, Scott J; Luyten, Frank P; Van Gool, Stefaan W; Sampaolesi, Maurilio; Delforge, Michel; Luttun, Aernout; Verfaillie, Catherine M

    2011-05-01

    Several adherent postnatal stem cells have been described with different phenotypic and functional properties. As many of these cells are being considered for clinical therapies, it is of great importance that the identity and potency of these products is validated. We compared the phenotype and functional characteristics of human mesenchymal stem cells (hMSCs), human mesoangioblasts (hMab), and human multipotent adult progenitor cells (hMAPCs) using uniform standardized methods. Human MAPCs could be expanded significantly longer in culture. Differences in cell surface marker expression were found among the three cell populations with CD140b being a distinctive marker among the three cell types. Differentiation capacity towards adipocytes, osteoblasts, chondrocytes, and smooth muscle cells in vitro, using established protocols, was similar among the three cell types. However, only hMab differentiated to skeletal myocytes, while only hMAPCs differentiated to endothelium in vitro and in vivo. A comparative transcriptome analysis confirmed that the three cell populations are distinct and revealed gene signatures that correlated with their specific functional properties. Furthermore, we assessed whether the phenotypic, functional, and transcriptome features were mediated by the culture conditions. Human MSCs and hMab cultured under MAPC conditions became capable of generating endothelial-like cells, whereas hMab lost some of their ability to generate myotubes. By contrast, hMAPCs cultured under MSC conditions lost their endothelial differentiation capacity, whereas this was retained when cultured under Mab conditions, however, myogenic capacity was not gained under Mab conditions. These studies demonstrate that hMSCs, hMab, and hMAPCs have different properties that are partially mediated by the culture conditions. Copyright © 2011 AlphaMed Press.

  8. A LEGO Mindstorms Brewster angle microscope

    NASA Astrophysics Data System (ADS)

    Fernsler, Jonathan; Nguyen, Vincent; Wallum, Alison; Benz, Nicholas; Hamlin, Matthew; Pilgram, Jessica; Vanderpoel, Hunter; Lau, Ryan

    2017-09-01

    A Brewster Angle Microscope (BAM) built from a LEGO Mindstorms kit, additional LEGO bricks, and several standard optics components, is described. The BAM was built as part of an undergraduate senior project and was designed, calibrated, and used to image phospholipid, cholesterol, soap, and oil films on the surface of water. A BAM uses p-polarized laser light reflected off a surface at the Brewster angle, which ideally yields zero reflectivity. When a film of different refractive index is added to the surface a small amount of light is reflected, which can be imaged in a microscope camera. Films of only one molecule (approximately 1 nm) thick, a monolayer, can be observed easily in the BAM. The BAM was used in a junior-level Physical Chemistry class to observe phase transitions of a monolayer and the collapse of a monolayer deposited on the water surface in a Langmuir trough. Using a photometric calculation, students observed a change in thickness of a monolayer during a phase transition of 7 Å, which was accurate to within 1 Å of the value determined by more advanced methods. As supplementary material, we provide a detailed manual on how to build the BAM, software to control the BAM and camera, and image processing software.

  9. Femtosecond photoelectron point projection microscope

    SciTech Connect

    Quinonez, Erik; Handali, Jonathan; Barwick, Brett

    2013-10-15

    By utilizing a nanometer ultrafast electron source in a point projection microscope we demonstrate that images of nanoparticles with spatial resolutions of the order of 100 nanometers can be obtained. The duration of the emission process of the photoemitted electrons used to make images is shown to be of the order of 100 fs using an autocorrelation technique. The compact geometry of this photoelectron point projection microscope does not preclude its use as a simple ultrafast electron microscope, and we use simple analytic models to estimate temporal resolutions that can be expected when using it as a pump-probe ultrafast electron microscope. These models show a significant increase in temporal resolution when comparing to ultrafast electron microscopes based on conventional designs. We also model the microscopes spectroscopic abilities to capture ultrafast phenomena such as the photon induced near field effect.

  10. Transmission electron microscope CCD camera

    DOEpatents

    Downing, Kenneth H.

    1999-01-01

    In order to improve the performance of a CCD camera on a high voltage electron microscope, an electron decelerator is inserted between the microscope column and the CCD. This arrangement optimizes the interaction of the electron beam with the scintillator of the CCD camera while retaining optimization of the microscope optics and of the interaction of the beam with the specimen. Changing the electron beam energy between the specimen and camera allows both to be optimized.

  11. Proper alignment of the microscope.

    PubMed

    Rottenfusser, Rudi

    2013-01-01

    The light microscope is merely the first element of an imaging system in a research facility. Such a system may include high-speed and/or high-resolution image acquisition capabilities, confocal technologies, and super-resolution methods of various types. Yet more than ever, the proverb "garbage in-garbage out" remains a fact. Image manipulations may be used to conceal a suboptimal microscope setup, but an artifact-free image can only be obtained when the microscope is optimally aligned, both mechanically and optically. Something else is often overlooked in the quest to get the best image out of the microscope: Proper sample preparation! The microscope optics can only do its job when its design criteria are matched to the specimen or vice versa. The specimen itself, the mounting medium, the cover slip, and the type of immersion medium (if applicable) are all part of the total optical makeup. To get the best results out of a microscope, understanding the functions of all of its variable components is important. Only then one knows how to optimize these components for the intended application. Different approaches might be chosen to discuss all of the microscope's components. We decided to follow the light path which starts with the light source and ends at the camera or the eyepieces. To add more transparency to this sequence, the section up to the microscope stage was called the "Illuminating Section", to be followed by the "Imaging Section" which starts with the microscope objective. After understanding the various components, we can start "working with the microscope." To get the best resolution and contrast from the microscope, the practice of "Koehler Illumination" should be understood and followed by every serious microscopist. Step-by-step instructions as well as illustrations of the beam path in an upright and inverted microscope are included in this chapter. A few practical considerations are listed in Section 3.

  12. Reflectance confocal microscopy for inflammatory skin diseases.

    PubMed

    Ardigò, M; Prow, T; Agozzino, M; Soyer, P; Berardesca, E

    2015-10-01

    Reflectance confocal microscopy evaluation of inflammatory skin diseases represents a relatively new indication that, during the last 5 years, has shown an increasing interest with consequent progressive increment of publications in literature. The success of RCM in this filed of dermatology is directly related to the high needing of non-invasive techniques able to reduce the number of skin biopsies and support the clinical diagnosis and patient's management. RCM demonstrated to visualize microscopic descriptors of inflammatory and pigmentary skin conditions with good reproducibility between observer and high grade of correspondence with optical histology. Moreover, RCM has shown to provide sufficient data to support clinical diagnosis and differential diagnosis of inflammatory and pigmentary skin diseases. Recently, several works published in literature have opened the prospective to use RCM also for therapeutic follow-up in order to monitor the improvement of the microscopic parameters and help to prevent treatment side effects. In this review article we present some examples of RCM application in inflammatory and pigmentary diseases.

  13. Approximating the detection limit of an infrared spectroscopic imaging microscope operating in an attenuated total reflection (ATR) modality: theoretical and empirical results for an instrument using a linear array detector and a 1.5 millimeter germanium hemisphere internal reflection element.

    PubMed

    Lanzarotta, Adam

    2015-01-01

    Theoretical and empirical detection limits have been estimated for aripiprazole (analyte) in alpha lactose monohydrate (matrix model pharmaceutical formulation) using a micro-attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopic imaging instrument equipped with a linear array detector and a 1.5 mm germanium hemisphere internal reflection element (IRE). The instrument yielded a theoretical detection limit of 0.0035% (35 parts per million (ppm)) when operating under diffraction-limited conditions, which was 49 times lower than what was achieved with a traditional macro-ATR instrument operating under practical conditions (0.17%, 1700 ppm). However, these results may not be achievable for most analyses because the detection limits will be particle size limited, rather than diffraction limited, for mixtures with average particle diameters greater than 8.3 μm (most pharmaceutical samples). For example, a theoretical detection limit of 0.028% (280 ppm) was calculated for an experiment operating under particle size-limited conditions where the average particle size was 23.4 μm. These conditions yielded a detection limit of 0.022% (220 ppm) when measured empirically, which was close to the theoretical value and only eight times lower than that of a faster, more simplistic macro-ATR instrument. Considering the longer data acquisition and processing times characteristic of the micro-ATR imaging approach (minutes or even hours versus seconds), the cost-benefit ratio may not often be favorable for the analysis of analytes in matrices that exhibit only a few overlapping absorptions (low-interfering matrices such as alpha lactose monohydrate) using this technique compared to what can be achieved using macro-ATR. However, the advantage was significant for detecting analytes in more complex matrices (those that exhibited several overlapping absorptions with the analyte) because the detection limit of the macro-ATR approach was highly formulation

  14. Submerged Reflectance

    DTIC Science & Technology

    1976-08-01

    at 450 and viewed at 0* (i.e., viewed nor1al to the surface). Instruments for performing this particular bi-directional reflectance measurement are...are described below. 3.1 THEORY OF ABSOLUTE SUBMERGED REFLECTANCE MEASUREMENT An absolute measurement of the reflectance of a surface can be obtained by...relative reflectance measurement is shown in Figure 2. The irradiance across the target will vary within the field of view of the photometer because

  15. Athena microscopic Imager investigation

    USGS Publications Warehouse

    Herkenhoff, K. E.; Squyres, S. W.; Bell, J.F.; Maki, J.N.; Arneson, H.M.; Bertelsen, P.; Brown, D.I.; Collins, S.A.; Dingizian, A.; Elliott, S.T.; Goetz, W.; Hagerott, E.C.; Hayes, A.G.; Johnson, M.J.; Kirk, R.L.; McLennan, S.; Morris, R.V.; Scherr, L.M.; Schwochert, M.A.; Shiraishi, L.R.; Smith, G.H.; Soderblom, L.A.; Sohl-Dickstein, J. N.; Wadsworth, M.V.

    2003-01-01

    The Athena science payload on the Mars Exploration Rovers (MER) includes the Microscopic Imager (MI). The MI is a fixed-focus camera mounted on the end of an extendable instrument arm, the Instrument Deployment Device (IDD). The MI was designed to acquire images at a spatial resolution of 30 microns/pixel over a broad spectral range (400-700 nm). The MI uses the same electronics design as the other MER cameras but has optics that yield a field of view of 31 ?? 31 mm across a 1024 ?? 1024 pixel CCD image. The MI acquires images using only solar or skylight illumination of the target surface. A contact sensor is used to place the MI slightly closer to the target surface than its best focus distance (about 66 mm), allowing concave surfaces to be imaged in good focus. Coarse focusing (???2 mm precision) is achieved by moving the IDD away from a rock target after the contact sensor has been activated. The MI optics are protected from the Martian environment by a retractable dust cover. The dust cover includes a Kapton window that is tinted orange to restrict the spectral bandpass to 500-700 nm, allowing color information to be obtained by taking images with the dust cover open and closed. MI data will be used to place other MER instrument data in context and to aid in petrologic and geologic interpretations of rocks and soils on Mars. Copyright 2003 by the American Geophysical Union.

  16. Differentiation between nerve and adipose tissue using wide-band (350-1,830 nm) in vivo diffuse reflectance spectroscopy.

    PubMed

    Schols, Rutger M; ter Laan, Mark; Stassen, Laurents P S; Bouvy, Nicole D; Amelink, Arjen; Wieringa, Fokko P; Alic, Lejla

    2014-09-01

    Intraoperative nerve localization is of great importance in surgery. In certain procedures, where nerves show visual resemblance to surrounding adipose tissue, this can be particularly challenging for the human eye. An example of such a delicate procedure is thyroid and parathyroid surgery, where iatrogenic injury of the recurrent laryngeal nerve can result in transient or permanent vocal problems (0.5-2.0% reported incidence). A camera system, enabling nerve-specific image enhancement, would be useful in preventing such complications. This might be realized with hyperspectral camera technology using silicon (Si) or indium gallium arsenide (InGaAs) sensor chips. As a first step towards such a camera, we evaluated the performance of diffuse reflectance spectroscopy by analysing spectra collected during 18 thyroid and parathyroid resections. We assessed the contrast information present in two different spectral ranges, for respectively Si and InGaAs sensors. Two hundred fifty three in vivo, wide-band diffuse reflectance spectra (350-1,830 nm range, 1 nm resolution) were acquired on 52 tissue spots, including nerve (n = 22), muscle (n = 12), and adipose tissue (n = 18). We extracted 36 features from these spectroscopic data: 18 gradients and 18 amplitude differences at predefined points in the tissue spectra. Best distinctive feature combinations were established using binary logistic regression. Classification performance was evaluated in a cross-validation (CV) approach by leave-one-out (LOO). To generalize nerve recognition applicability, we performed a train-test (TT) validation using the thyroid and parathyroid surgery data for training purposes and carpal tunnel release surgery data (10 nerve spots and 5 adipose spots) for classification purposes. For combinations of two distinctive spectral features, LOO revealed an accuracy of respectively 78% for Si-sensors and 95% for InGaAs-sensors. TT revealed accuracies of respectively 67% and 100%. Using

  17. Scientists View Battery Under Microscope

    SciTech Connect

    2015-04-10

    PNNL researchers use a special microscope setup that shows the inside of a battery as it charges and discharges. This battery-watching microscope is located at EMSL, DOE's Environmental Molecular Sciences Laboratory that resides at PNNL. Researchers the world over can visit EMSL and use special instruments like this, many of which are the only one of their kind available to scientists.

  18. The Latest in Handheld Microscopes

    ERIC Educational Resources Information Center

    Wighting, Mervyn J.; Lucking, Robert A.; Christmann, Edwin P.

    2004-01-01

    Around 1590, Zacharias Jansenn of Holland invented the microscope. Jansenn, an eyeglass maker by trade, experimented with lenses and discovered that things appeared closer with combinations of lenses. Over the past 400 years, several refinements to microscopes have occurred, making it possible to magnify objects between 200 and 1,500 times their…

  19. Mars Life? - Microscopic Tubular Structures

    NASA Image and Video Library

    1996-08-09

    This electron microscope image shows extremely tiny tubular structures that are possible microscopic fossils of bacteria-like organisms that may have lived on Mars more than 3.6 billion years ago. http://photojournal.jpl.nasa.gov/catalog/PIA00285

  20. The Latest in Handheld Microscopes

    ERIC Educational Resources Information Center

    Wighting, Mervyn J.; Lucking, Robert A.; Christmann, Edwin P.

    2004-01-01

    Around 1590, Zacharias Jansenn of Holland invented the microscope. Jansenn, an eyeglass maker by trade, experimented with lenses and discovered that things appeared closer with combinations of lenses. Over the past 400 years, several refinements to microscopes have occurred, making it possible to magnify objects between 200 and 1,500 times their…

  1. Scientists View Battery Under Microscope

    ScienceCinema

    None

    2016-07-12

    PNNL researchers use a special microscope setup that shows the inside of a battery as it charges and discharges. This battery-watching microscope is located at EMSL, DOE's Environmental Molecular Sciences Laboratory that resides at PNNL. Researchers the world over can visit EMSL and use special instruments like this, many of which are the only one of their kind available to scientists.

  2. Microscopic anatomy: normal structure.

    PubMed

    King, Rosalind

    2013-01-01

    A peripheral nerve trunk is composed of nerve fascicles supported in a fibrous collagenous sheath and defined by concentric layers of cells (the perineurium) that separate the contents (the endoneurium) from its fibrous collagen support (the epineurium). In the endoneurium are myelinated and unmyelinated fibers that are axons combined with their supporting Schwann cells to provide physical and electrical connections with end-organs such as muscle fibers and sensory endings. Axons are tubular neuronal extensions with a cytoskeleton of neurotubules and tubulin along which organelles and proteins can travel between the neuronal cell body and the axon terminal. During development some axons enlarge and are covered by a chain of Schwann cells each associated with just one axon. As the axons grow in diameter, the Schwann cells wrap round them to produce a myelin sheath. This consists of many layers of compacted Schwann cell membrane plus some additional proteins. Adjacent myelin segments connect at highly specialized structures, the nodes of Ranvier. Myelin insulates the axon so that the nerve impulse can jump from one node to the next. The region adjacent to the node, the paranodal segment, is the site of myelin terminations on the axolemma. There are connections here between the Schwann cell and the axon via a complex chain of proteins. The Schwann cell cytoplasm in the adjacent segment, the juxtaparanode, contains most of the Schwann cell mitochondria. In addition to the node, continuity of myelin lamellae is broken at intervals along the internode by helical regions of decompaction known as Schmidt-Lanterman incisures; these are seen as paler conical segments in suitably stained microscopical preparations and provide a pathway between the adaxonal and abaxonal cytoplasm. Smaller axons without a myelin sheath conduct very much more slowly and have a more complex relationship with their supporting Schwann cells that has important implications for repair. Copyright

  3. Subsurface Imaging with the Scanning Microwave Microscope

    NASA Astrophysics Data System (ADS)

    Kopanski, Joseph; You, Lin; Michelson, Jonathan; Hitz, Emily; Obeng, Yaw; Back End of the Line Reliability; Metrology Project Team

    2015-03-01

    The scanning microwave microscope (SMM) forms images from the reflected amplitude and phase of an incident RF (~ 2.3 GHz) signal. The reflected signal is a function of the properties of the tip-sample contact, but can also be influenced by buried interfaces and subsurface variations of the sample permittivity. This mechanism allows limited imaging of conductors buried within dielectrics, voids within metal, or multiple metal layers with different permittivity. Subsurface SMM data acquisition modes include passive and various active data acquisition modes. The theory of sub-surface imaging with SMM and COMSOL multi-physics simulations of specific situations will be presented. Measurements of specifically designed test structures and correlation with simulations show the sensitivity and resolution of the technique applied to imaging subsurface metal lines embedded in dielectric. Applications include metrology for back end of the line (BEOL) multi-level metallization and three-dimensional integrated circuits (3D-ICs).

  4. Inter-Trial Correlations in Predictive-Saccade Endpoints: Fractal Scaling Reflects Differential Control along Task-Relevant and Orthogonal Directions

    PubMed Central

    Federighi, Pamela; Wong, Aaron L.; Shelhamer, Mark

    2017-01-01

    Saccades exhibit variation in performance from one trial to the next, even when paced at a constant rate by targets at two fixed locations. We previously showed that amplitude fluctuations in consecutive predictive saccades have fractal structure: the spectrum of the sequence of consecutive amplitudes has a power-law (f −α) form, indicative of inter-trial correlations that reflect the storage of prior performance information to guide the planning of subsequent movements. More gradual decay of these inter-trial correlations coincides with a larger magnitude of spectral slope α, and indicates stronger information storage over longer times. We have previously demonstrated that larger decay exponents (α) are associated with faster adaptation in a saccadic double-step task. Here, we extend this line of investigation to predictive saccade endpoints (i.e., movement errors). Subjects made predictive, paced saccades between two fixed targets along a horizontal or vertical axis. Endpoint fluctuations both along (on-axis) and orthogonal to (off-axis) the direction of target motion were examined for correlations and fractal structure. Endpoints in the direction of target motion had little or no correlation or power-law scaling, suggesting that successive movements were uncorrelated (white noise). In the orthogonal direction, however, the sequence of endpoints did exhibit inter-trial correlations and scaling. In contrast, in our previous work the scaling of saccade amplitudes is strong along the target direction. This may reflect the fact that while saccade amplitudes are neurally programmed, endpoints are not directly controlled but instead serve as a source of error feedback. Hence, the lack of correlations in on-axis endpoint errors suggests that maximum information has been extracted from previous movement errors to plan subsequent movement amplitudes. In contrast, correlations in the off-axis component indicate that useful information still remains in this error

  5. LOCAL MAGNETIC BEHAVIOR OF 54Fe in EuFe2As2 AND Eu0.5K0.5Fe2As2: MICROSCOPIC STUDY USING TIME DIFFERENTIAL PERTURBED ANGULAR DISTRIBUTION (TDPAD) SPECTROSCOPY

    NASA Astrophysics Data System (ADS)

    Mohanta, S. K.; Mishra, S. N.; Davane, S. M.; Layek, S.; Hossain, Z.

    2013-12-01

    In this paper, we report the time differential perturbed angular distribution measurements of 54Fe on a polycrystalline EuFe2As2 and Eu0.5K0.5Fe2As2. The hyperfine field and nuclear spin-relaxation rate are strongly temperature dependent in the paramagnetic state suggesting strong spin fluctuation in the parent compound. The local susceptibility show Curie-Weiss-like temperature dependence and Korringa-like relaxation in the tetragonal phase indicating the presence of local moment. In the orthorhombic phase, the hyperfine field behavior suggesting quasi two-dimensional magnetic ordering. The experimental results are in a good agreement with first-principle calculations based on density functional theory.

  6. Immunohistochemical study of Ulex europaeus agglutinin 1 (UEA-1) binding of megakaryocytes in bone marrow biopsy specimens: demonstration of heterogeneity in staining pattern reflecting the stages of differentiation.

    PubMed

    Liu, S M; Li, C Y

    1996-01-01

    During differentiation, megakaryocytes undergo nuclear endoreplication, an increase in cell size, cytoplasmic granulation, and release of platelets. The changes in highly lobulated nuclei with varying degree of polyploidy and increasing cell size are easily recognized morphologically. However, the actual cytoplasmic changes are more difficult to perceive morphologically. With the peroxidase-antiperoxidase (PAP) method using UEA-1 as the binding protein to the alpha-L-fucose of glycoprotein synthesized by megakaryocytes, we observed significant variation in cytoplasmic staining of megakaryocytes in routinely processed bone marrow biopsy sections. A total of 3344 megakaryocytes in bone marrow sections from 10 patients with nonhematologic diseases and from 10 patients with idiopathic thrombocytopenic purpura (ITP) was studied. According to the intensity and pattern of cytoplasmic staining, we divided megakaryocytes into at least six groups: (1) low granular (LG), (2) diffuse granular (DG), (3) diffuse dense granular (DDG), (4) marginal granular (MG), (5) denuded (DMK), and (6) endomitotic (EndoM). Most of the megakaryocytes were DG (mean, 42.75% +/- 19.21%) and DDG (mean, 50.25% +/- 21.23%). In correlation with nuclear morphology and cell size, it appears that substances binding to UEA-1 are located in the paranuclear region in early megakaryocytes and produce a low granular focal staining pattern (LG cells). Next, the granules spread throughout the cytoplasm (DG cells) and increase in quantity (DDG). This is followed by migration of granules to the periphery of the cytoplasm (MG cells) and is associated with the liberation of platelets and eventual formation of DMK megakaryocytes. Endomitosis, regulated by unknown factors, occurred in the MG stage. In comparing the group with nonhematologic disease (mean DG, 35.4% +/- 18.48%; DDG, 58.4% +/- 21.8%) and the group with ITP (mean DG, 50.1% +/- 17.82%; DDG, 42.1% +/- 18.12%), we found an increasing proportion of DG

  7. Differential protein expression and localization of CYP450 enzymes in three species of earthworm; is this a reflection of environmental adaptation?

    PubMed

    Lu, Xiaoxu; Li, Yinsheng; Thunders, Michelle; Cavanagh, Jo; Matthew, Cory; Wang, Xiuhong; Zhou, Xinchu; Qiu, Jiangping

    2017-03-01

    Cytochrome P450 (CYP450) is a hemoprotein superfamily, among which CYP1, CYP2 and CYP3 play a major role in the metabolism of vast array of xenobiotics and endobiotics. This paper reports on three CYP enzyme variants (CYP1A2, CYP2E1 and CYP3A4) in three species of earthworm (Eisenia fetida, Metaphire guillelmi and Amynthas carnosus). The relative expression levels and localization of the three associated proteins were investigated at three life-cycle points (juvenile, sub-adult and adult), through comparison of anterior and posterior body tissue and between specific organs (body wall, intestine and reproductive tissues) using western blot analysis. This study confirmed the presence of CYP3A4, CYP1A2 and CYP2E1 in all three species of earthworm tested. The levels of expression varied with earthworm species, age, and body location. These differences in occurrence of the three CYP enzymes appeared to reflect the ecological niche (the spatial and temporal location and functional relationship of each individual or population in populations or communities), and the likelihood of contact with soil contaminants of the respective species. These results may help to explain why earthworms are capable of adapting to very different and extensively polluted soil environments and provide important data for subsequent ecotoxicology and ecological adaptability studies.

  8. The head-mounted microscope.

    PubMed

    Chen, Ting; Dailey, Seth H; Naze, Sawyer A; Jiang, Jack J

    2012-04-01

    Microsurgical equipment has greatly advanced since the inception of the microscope into the operating room. These advancements have allowed for superior surgical precision and better post-operative results. This study focuses on the use of the Leica HM500 head-mounted microscope for the operating phonosurgeon. The head-mounted microscope has an optical zoom from 2× to 9× and provides a working distance from 300 mm to 700 mm. The headpiece, with its articulated eyepieces, adjusts easily to head shape and circumference, and offers a focus function, which is either automatic or manually controlled. We performed five microlaryngoscopic operations utilizing the head-mounted microscope with successful results. By creating a more ergonomically favorable operating posture, a surgeon may be able to obtain greater precision and success in phonomicrosurgery. Phonomicrosurgery requires the precise manipulation of long-handled cantilevered instruments through the narrow bore of a laryngoscope. The head-mounted microscope shortens the working distance compared with a stand microscope, thereby increasing arm stability, which may improve surgical precision. Also, the head-mounted design permits flexibility in head position, enabling operator comfort, and delaying musculoskeletal fatigue. A head-mounted microscope decreases the working distance and provides better ergonomics in laryngoscopic microsurgery. These advances provide the potential to promote precision in phonomicrosurgery.

  9. Erythropoiesis-driven regulation of hepcidin in human red cell disorders is better reflected through concentrations of soluble transferrin receptor rather than growth differentiation factor 15.

    PubMed

    Fertrin, Kleber Yotsumoto; Lanaro, Carolina; Franco-Penteado, Carla Fernanda; de Albuquerque, Dulcinéia Martins; de Mello, Mariana Rezende Bandeira; Pallis, Flávia Rubia; Bezerra, Marcos André Cavalcanti; Hatzlhofer, Betania Lucena Domingues; Olbina, Gordana; Saad, Sara Terezinha Olalla; da Silva Araújo, Aderson; Westerman, Mark; Costa, Fernando Ferreira

    2014-04-01

    Growth differentiation factor 15 (GDF-15) is a bone marrow-derived cytokine whose ability to suppress iron regulator hepcidin in vitro and increased concentrations found in patients with ineffective erythropoiesis (IE)suggest that hepcidin deficiency mediated by GDF-15 may be the pathophysiological explanation for nontransfusional iron overload. We aimed to compare GDF-15 production in anemic states with different types of erythropoietic dysfunction. Complete blood counts, biochemical markers of iron status, plasma hepcidin, GDF-15, and known hepcidin regulators [interleukin-6 and erythropoietin (EPO)] were measured in 87 patients with red cell disorders comprising IE and hemolytic states: thalassemia, sickle cell anemia, and cobalamin deficiency. Healthy volunteers were also evaluated for comparison. Neither overall increased EPO,nor variable GDF-15 concentrations correlated with circulating hepcidin concentrations (P = 0.265 and P = 0.872). Relative hepcidin deficiency was found in disorders presenting with concurrent elevation of GDF-15 and soluble transferrin receptor (sTfR), a biomarker of erythropoiesis, and sTfR had the strongest correlation with hepcidin (r(s) = 0.584, P < 0.0001). Our data show that high concentrations of GDF-15 in vivo are not necessarily associated with pathological hepcidin reduction, and hepcidin deficiency was only found when associated with sTfR overproduction. sTfR elevation may be a necessary common denominator of erythropoiesis-driven mechanisms to favor iron absorption in anemic states and appears a suitable target for investigative approaches to iron disorders.

  10. Nuclear features in different grades of epithelial dysplasia in leukoplakia: A computer assisted microscopic study

    PubMed Central

    Gadiwan, Mohsin; Madhushankari, GS; Mandana, DD; Praveen, SB; Selvamani, MS; Pradeep, DS

    2014-01-01

    Context: Abnormalities in nuclear morphology are very frequently seen in dysplasia, such as nuclear area, diameter, shape, number of nucleoli and membrane outline. The purpose of this study was to observe and compare the nuclear features in different grades of epithelial dysplasia in leukoplakia and to evaluate the use of Feulgen stain for observing the nuclear features in oral epithelial dysplasia in leukoplakia. Seventy paraffin embedded tissue section (20 mild, 20 moderate, 20 severe dysplasia cases and 10 control specimens) were analyzed for nuclear morphology using Feulgen stain under trinocular research microscope. Statistically significant results were obtained with P > 0.001, when intergroup comparison was done except in case of nuclear area and diameter between mild and moderate dysplasia. Nuclear features reflect cell's biological potential and its morphometry was found to be a useful tool for differentiating different grades of dysplasia. PMID:25328298

  11. Nuclear features in different grades of epithelial dysplasia in leukoplakia: A computer assisted microscopic study.

    PubMed

    Gadiwan, Mohsin; Madhushankari, Gs; Mandana, Dd; Praveen, Sb; Selvamani, Ms; Pradeep, Ds

    2014-05-01

    Abnormalities in nuclear morphology are very frequently seen in dysplasia, such as nuclear area, diameter, shape, number of nucleoli and membrane outline. The purpose of this study was to observe and compare the nuclear features in different grades of epithelial dysplasia in leukoplakia and to evaluate the use of Feulgen stain for observing the nuclear features in oral epithelial dysplasia in leukoplakia. Seventy paraffin embedded tissue section (20 mild, 20 moderate, 20 severe dysplasia cases and 10 control specimens) were analyzed for nuclear morphology using Feulgen stain under trinocular research microscope. Statistically significant results were obtained with P > 0.001, when intergroup comparison was done except in case of nuclear area and diameter between mild and moderate dysplasia. Nuclear features reflect cell's biological potential and its morphometry was found to be a useful tool for differentiating different grades of dysplasia.

  12. Single-electron tunneling. [Microwave scanning tunneling microscope

    SciTech Connect

    Ruggiero, S.T.

    1993-01-01

    Pictures using the low-temperature microwave scanning tunneling microscope, have been made of particles and tunneling IV characteristics determined. Strong, sometimes periodic negative differential resistance was observed in small-particle systems. Au and Ag droplets and particles were studied. 4 figs.

  13. Spatial genetic structure of bristle-thighed curlews (Numenius tahitiensis): breeding area differentiation not reflected on the non-breeding grounds

    USGS Publications Warehouse

    Sonsthagen, Sarah A.; Tibbitts, T. Lee; Gill, Robert E.; Williams, Ian S.; Talbot, Sandra L.

    2015-01-01

    Migratory birds occupy geographically and ecologically disparate areas during their annual cycle with conditions on breeding and non-breeding grounds playing separate and important roles in population dynamics. We used data from nuclear microsatellite and mitochondrial DNA control region loci to assess the breeding and non-breeding spatial genetic structure of a transoceanic migrant shorebird, the bristle-thighed curlew. We found spatial variance in the distribution of allelic and haplotypic frequencies between the curlew's two breeding areas in Alaska but did not observe this spatial structure throughout its non-breeding range on low-lying tropical and subtropical islands in the Central Pacific (Oceania). This suggests that the two breeding populations do not spatially segregate during the non-breeding season. Lack of migratory connectivity is likely attributable to the species' behavior, as bristle-thighed curlews exhibit differential timing of migration and some individuals move among islands during non-breeding months. Given the detrimental impact of many past and current human activities on island ecosystems, admixture of breeding populations in Oceania may render the bristle-thighed curlew less vulnerable to perturbations there, as neither breeding population will be disproportionally affected by local habitat losses or by stochastic events. Furthermore, lack of migratory connectivity may enable bristle-thighed curlews to respond to changing island ecosystems by altering their non-breeding distribution. However, availability of suitable non-breeding habitat for curlews in Oceania is increasingly limited on both low-lying and high islands by habitat loss, sea level rise, and invasive mammalian predators that pose a threat to flightless and flight-compromised curlews during the molting period.

  14. Micro-reflectance and transmittance spectroscopy: a versatile and powerful tool to characterize 2D materials

    NASA Astrophysics Data System (ADS)

    Frisenda, Riccardo; Niu, Yue; Gant, Patricia; Molina-Mendoza, Aday J.; Schmidt, Robert; Bratschitsch, Rudolf; Liu, Jinxin; Fu, Lei; Dumcenco, Dumitru; Kis, Andras; Perez De Lara, David; Castellanos-Gomez, Andres

    2017-02-01

    Optical spectroscopy techniques such as differential reflectance and transmittance have proven to be very powerful techniques for studying 2D materials. However, a thorough description of the experimental setups needed to carry out these measurements is lacking in the literature. We describe a versatile optical microscope setup for carrying out differential reflectance and transmittance spectroscopy in 2D materials with a lateral resolution of ~1 µm in the visible and near-infrared part of the spectrum. We demonstrate the potential of the presented setup to determine the number of layers of 2D materials and characterize their fundamental optical properties, such as excitonic resonances. We illustrate its performance by studying mechanically exfoliated and chemical vapor-deposited transition metal dichalcogenide samples.

  15. Adirondack Under the Microscope-2

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This overhead look at the martian rock dubbed Adirondack was captured by the Mars Exploration Rover Spirit's panoramic camera. It shows the approximate region where the rover's microscopic imager began its first close-up inspection.

  16. Microscopic Procedures for Plant Meiosis.

    ERIC Educational Resources Information Center

    Braselton, James P.

    1997-01-01

    Describes laboratory techniques designed to familiarize students with meiosis and how microscopic preparations of meiosis are made. These techniques require the use of fresh or fixed flowers. Contains 18 references. (DDR)

  17. Recent Athena Microscopic Imager Results

    NASA Astrophysics Data System (ADS)

    Herkenhoff, K. E.; Ashley, J. W.; Johnson, J. R.; Parker, T. J.; Athena Science Team

    2012-03-01

    The Mars Exploration Rover Opportunity arrived at the rim of Endeavour Crater in August 2011. This presentation summarizes Opportunity Microscopic Imager observations of ejecta, bedrock, a gypsum vein, and other materials in the crater rim rocks.

  18. Adirondack Under the Microscope-2

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This overhead look at the martian rock dubbed Adirondack was captured by the Mars Exploration Rover Spirit's panoramic camera. It shows the approximate region where the rover's microscopic imager began its first close-up inspection.

  19. Mars Life? - Microscopic Tubular Structures

    NASA Image and Video Library

    1996-08-09

    This electron microscope image shows tubular structures of likely Martian origin. These structures are very similar in size and shape to extremely tiny microfossils found in some Earth rocks. http://photojournal.jpl.nasa.gov/catalog/PIA00287

  20. Microscopic Procedures for Plant Meiosis.

    ERIC Educational Resources Information Center

    Braselton, James P.

    1997-01-01

    Describes laboratory techniques designed to familiarize students with meiosis and how microscopic preparations of meiosis are made. These techniques require the use of fresh or fixed flowers. Contains 18 references. (DDR)

  1. Magnetic Resonance Force Microscope Development

    SciTech Connect

    Hammel, P.C.; Zhang, Z.; Suh, B.J.; Roukes, M.L.; Midzor, M.; Wigen, P.E.; Childress, J.R.

    1999-06-03

    Our objectives were to develop the Magnetic Resonance Force Microscope (MRFM) into an instrument capable of scientific studies of buried structures in technologically and scientifically important electronic materials such as magnetic multilayer materials. This work resulted in the successful demonstration of MRFM-detected ferromagnetic resonance (FMR) as a microscopic characterization tool for thin magnetic films. Strong FMR spectra obtained from microscopic Co thin films (500 and 1000 angstroms thick and 40 x 200 microns in lateral extent) allowed us to observe variations in sample inhomogeneity and magnetic anisotropy field. We demonstrated lateral imaging in microscopic FMR for the first time using a novel approach employing a spatially selective local field generated by a small magnetically polarized spherical crystallite of yttrium iron garnet. These successful applications of the MRFM in materials studies provided the basis for our successful proposal to DOE/BES to employ the MRF M in studies of buried interfaces in magnetic materials.

  2. (Center of excellence: Microlaser microscope)

    SciTech Connect

    Webb, R.H.

    1992-01-01

    This Center-of-Excellence grant has two components: development of an imaging system based on microlaser arrays forms a central project among a group of laser diagnostic and therapeutic efforts primarily funded outside the grant. In these first 8 months we have set up the Microlaser Microscope using small microlaser arrays. We have emphasized the basics of microlaser handling and electronic addressing and the optics of the microscope. Details of electronics and optics given here will be used in the larger arrays which should be available soon. After a description of the central Microlaser Microscope project, we touch briefly on the other projects of the Center, which have been outstandingly fruitful this year. Publications are necessarily concerned with the smaller projects, since the Microlaser Microscope is in its early stages.

  3. Mars Life? - Microscopic Tubular Structures

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This electron microscope image shows extremely tiny tubular structures that are possible microscopic fossils of bacteria-like organisms that may have lived on Mars more than 3.6 billion years ago. A two-year investigation by a NASA research team found organic molecules, mineral features characteristic of biological activity and possible microscopic fossils such as these inside of an ancient Martian rock that fell to Earth as a meteorite. The largest possible fossils are less than 1/100th the diameter of a human hair in size while most are ten times smaller. The fossil-like structures were found in carbonate minerals formed along pre-existing fractures in the meteorite in a fashion similar to the way fossils occur in limestone on Earth, although on a microscopic scale.

  4. On thermodynamic and microscopic reversibility

    SciTech Connect

    Crooks, Gavin E.

    2011-07-12

    The word 'reversible' has two (apparently) distinct applications in statistical thermodynamics. A thermodynamically reversible process indicates an experimental protocol for which the entropy change is zero, whereas the principle of microscopic reversibility asserts that the probability of any trajectory of a system through phase space equals that of the time reversed trajectory. However, these two terms are actually synonymous: a thermodynamically reversible process is microscopically reversible, and vice versa.

  5. Taking Photographs with a Microscope

    PubMed Central

    Maude, Richard J.; Koh, Gavin C. K. W.; Silamut, Kamolrat

    2008-01-01

    We describe a simple, economical, and highly practical technique for taking digital photographs of specimens visualized through a light microscope. Most models of light microscope and compact digital camera, and even some cameraphones, can be used. The technique is quick to learn and can easily be performed in a resource-poor setting. It can be used to assist with diagnosis in remote areas and can be extremely useful for teaching. PMID:18784246

  6. Taking photographs with a microscope.

    PubMed

    Maude, Richard J; Koh, Gavin C K W; Silamut, Kamolrat

    2008-09-01

    We describe a simple, economical, and highly practical technique for taking digital photographs of specimens visualized through a light microscope. Most models of light microscope and compact digital camera, and even some cameraphones, can be used. The technique is quick to learn and can easily be performed in a resource-poor setting. It can be used to assist with diagnosis in remote areas and can be extremely useful for teaching.

  7. [MICROSCOPIC COLITIS: THE CLINICAL CASE].

    PubMed

    Kulygina, Y A; Skalinskaya, M I; Ageeva, T A

    2015-01-01

    During past years incidence and prevalence of microscopic colitis (MC) have increased, that is possible caused to the improvement of knowledge of doctors about the disease. This article contain modern views on epidemiology, diagnostic and variant of microscopic colitis treatment. A typical clinical picture of MC in the form of recurrent a watery diarrhea, with the absence of pathologic changes at roentgenologic and endoscopic investigations is described with the example of a clinical case.

  8. STM-SQUID probe microscope

    NASA Astrophysics Data System (ADS)

    Hayashi, Tadayuki; Tachiki, Minoru; Itozaki, Hideo

    2007-11-01

    We have developed a STM-SQUID probe microscope. A high TC SQUID probe microscope was combined with a scanning tunneling microscope for investigation of samples at room temperature in air. A high permeability probe needle was used as a magnetic flux guide to improve the spatial resolution. The probe with tip radius of less than 100 nm was prepared by microelectropolishing. The probe was also used as a scanning tunneling microscope tip. Topography of the sample surface could be measured by the scanning tunneling microscope with high spatial resolution prior to observation by SQUID microscopy. The SQUID probe microscope image could be observed while keeping the distance from the sample surface to the probe tip constant. We observed a topographic image and a magnetic image of Ni fine pattern and also a magnetically recorded hard disk. Furthermore we have investigated a sample vibration method of the static magnetic field emanating from a sample with the aim of achieving a higher signal-to-noise (S/N) ratio.

  9. Single-wavelength STED microscope

    NASA Astrophysics Data System (ADS)

    Baer, Stephen C.

    2011-03-01

    The zero-point STED microscope (US Pat. 5,866,911)1 was the first far-field microscope to overcome the diffraction limit, but optimally it requires two expensive synchronized short-pulsed lasers. Replacing the synchronized pulsed lasers with CW lasers had been proposed to reduce costs1, but this seriously reduced resolution compared to a similarly powered pulsed STED microscope. A recent theoretical and experimental study (Nat. Methods 4, 915 (2007))3 argued that CW STED has better resolution than previously believed, but there appear to be flaws in the theory sufficient to raise questions about its reported experimental confirmation. We describe an alternative approach to reducing cost of the STED microscope while preserving resolution. A portion of the beam from a femtosecond pulsed laser of a wavelength able to excite fluorescence by multiphoton absorption, is passed through a long optical fiber to stretch the pulses to reduce their peak power so they can no longer excite but can quench by stimulated emission. The stretched pulses are shaped into a doughnut profile and then recombined with the first beam for interaction with the specimen. With suitable fluorophores, this instrument should be able to match the resolution performance of the pulsed laser STED microscope using separate lasers. Particularly when added to an existing multiphoton microscope, such performance should be achievable at extremely low added cost.

  10. Reflecting on Reflecting on Practice

    ERIC Educational Resources Information Center

    Wilson, Arthur L.

    2009-01-01

    This article discusses three broad themes--reflection, power, and negotiation--that are evidenced in all of the articles in this issue. In this article, the author tries to transgress the articles at some middling altitude to seek some broader thematics. His observations about reflection, power, and negotiation do transcend individual efforts,…

  11. Development of the fast astigmatic auto-focus microscope system

    NASA Astrophysics Data System (ADS)

    Hsu, Wei-Yao; Lee, Chien-Shing; Chen, Po-Jui; Chen, Nien-Tsu; Chen, Fong-Zhi; Yu, Zong-Ru; Kuo, Ching-Hsiang; Hwang, Chi-Hung

    2009-04-01

    In this paper, a fast auto-focus microscope system was developed based on the astigmatic method. A collimated infrared laser beam was employed in the infinite-corrected microscope optical axis by the beam splitter and reflected by the sample surface. By embedding an astigmatic lens in the system, the reflected laser beam has different focal lengths in the sagittal and tangential planes. As the microscope's relative distance varies, the reflected laser beam shape also varies and can be detected by an embedded four-quadrant photodiode, i.e., the focus error signal (FES) can be found. Then, a fast auto-focus system can be realized by converting the FES to the microscope's defocus distance. We designed an astigmatic auto-focus system for a 20× objective lens with a ±50 µm working range, and this system could also be used for 10× and 5× objectives with ±200 µm and ±800 µm working ranges, respectively.

  12. Applications of 1 MV field-emission transmission electron microscope.

    PubMed

    Tonomura, Akira

    2003-01-01

    A newly developed 1 MV field-emission transmission electron microscope has recently been applied to the field of superconductivity by utilizing its bright and monochromatic field-emission electron beam. This microscope allows individual magnetic vortices inside high-Tc superconductors to be observed, thus, opening the way to investigate the unusual behaviour of vortices, which reflects the anisotropic layered structure of these superconducting materials. One example is the observation of the arrangements of chain vortex lines that are formed when a magnetic field is applied obliquely to the layer plane of the materials.

  13. Spectral confocal reflection microscopy using a white light source

    NASA Astrophysics Data System (ADS)

    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.

  14. Luttinger liquids from a microscopic perspective

    NASA Astrophysics Data System (ADS)

    Valiente, Manuel; Phillips, Lawrence G.; Zinner, Nikolaj T.; Öhberg, Patrik

    2017-09-01

    Luttinger liquid theory is a powerful and widely applicable framework for modelling one-dimensional many-body quantum systems. Within this framework, one supposes that the macroscopic behaviour of such systems is entirely determined by two phenomenological parameters, g 2 and g 4. While there exists an intuitive and seemingly sensible physical interpretation of these parameters in terms of the scattering of the system’s constituent particles, g 2 and g 4 are traditionally either fixed by experiment or calculated using heavy-duty numerical techniques, rather than inferred using scattering theory, and for this reason the interpretation remains untested. By applying Luttinger liquid theory in a simple setting, we show that a widely-held and repeatedly-stated belief, namely that the intrabranch terms appearing in Luttinger’s model originate from microscopic intrabranch interactions, is a misconception. We begin with the microscopic model of an interacting one-dimensional, spin-polarized Fermi gas, which we systematically transform into a Luttinger model by introducing an effective interaction, linearizing the dispersion, and renormalizing. By this method, we are able to show that the usual interpretation of g 4 as a measure of intrabranch scattering implies that it must vanish in the dilute limit. Since this runs contrary to conservation of particle number, we conclude that g 4 cannot be related to intrabranch scattering. Rather, we show that g 4 interactions must be included in the effective model in order to compensate for the deleterious effect that introducing an effective interaction has upon the model’s energetics. We explicitly calculate an approximation to this correction for our simple system, and find that it agrees with the value of g 4 found in the literature. We therefore propose a new fermionic Hamiltonian which agrees with the traditional model after bosonisation, but which better reflects the underlying microscopic physics.

  15. Applications Of The Microscope System LSM

    NASA Astrophysics Data System (ADS)

    Kapitza, Hans-Georg; Wilke, Volker

    1989-02-01

    The new universal confocal LSM is a second-generation laser scanning microscope. This means, that laser scanning microscopy now made the transition from experimental set-up lab types to integrated workstations, where the manual handling of mechanical and optical components is left to the computer. The built-in microcomputer - now not only drives scanners and transforms signals into images but also controls directly the microscope functions. It turned out that this is a crucial step for making the LSM an universal instrument for widespread use in research and development. The switching from conventiona] microscopy to laser scanning modes and vice versa is performed by simply pressing keys. Not only images can be stored on the built-in hard disk but at the same time automati cally the corresponding set of parameters: Even weeks or months after creating an image the settings of the instrument belonging to this image can be called from the operators panel by loading a parameter file which defines the laser line used and its intensity setting, nosepiece position, zoom factor, averaging conditions, microscopy mode (transmitted, reflected or fluorescence) and parameters for signal conditioning. Since the microscope stand is motorized at a high degree, the computer recreates automatically the exact conditions desired after dialing the number of the parameter file. In this way working with the LSM becomes not only reproducible, but also the user is freed from the handling of mechanical parts and typing commands on a keyboard. Finally the automatized LSM allows true remote control by a host computer necessary for the most demanding 3D-reconstruction. The characteristics pointed out so far are prerequisites for the daily use by microscopists in life science, semiconductor research, development and testing and materials research.

  16. Inclined selective plane illumination microscopy adaptor for conventional microscopes.

    PubMed

    Cutrale, Francesco; Gratton, Enrico

    2012-11-01

    Driven by the biological sciences, there is an increased need for imaging modalities capable of live cell imaging with high spatial and temporal resolution. To achieve this goal in a comprehensive manner, three-dimensional acquisitions are necessary. Ideal features of a modern microscope system should include high imaging speed, high contrast ratio, low photo-bleaching and photo-toxicity, good resolution in a 3D context, and mosaic acquisition for large samples. Given the importance of collecting data in live sample further increases the technical challenges required to solve these issues. This work presents a practical version of a microscopy method, Selective Plane Illumination Microscopy re-introduced by Huisken et al. (Science2004,305,1007-1009). This method is gaining importance in the biomedical field, but its use is limited by difficulties associated with unconventional microscope design which employs two objectives and a particular kind of sample preparation needed to insert the sample between the objectives. Based on the selective plane illumination principle but with a design similar to the Total Internal Reflection Fluorescence microscope, Dunsby (Dunsby, Opt Express 2008,16,20306-20316) demonstrated the oblique plane microscope (OPM) using a single objective which uses conventional sample preparation protocols. However, the Dunsby instrument was not intended to be part of a commercial microscope. In this work, we describe a system with the advantages of OPM and that can be used as an adaptor to commonly used microscopes, such as IX-71 Olympus, simplifying the construction of the OPM and increasing performance of a conventional microscope. We named our design inclined selective plane illumination microscope (iSPIM).

  17. Ergonomic microscope comfort and control.

    PubMed

    Thomas, Elizabeth Anne

    2011-03-01

    Microscope use in the inspection phase of computer chip manufacturing is a major cause of worker discomfort and injury. A two-phase ergonomics project to reduce employee fatigue and discomfort was planned, implemented, and evaluated in a microscope user environment within a high-technology manufacturing environment. Total Quality Management methodology and tools were employed by a multidisciplinary team led by an occupational health nurse practitioner to accomplish the project goals. A multifaceted approach including equipment changes, administrative changes, and focused training for behavior changes achieved the desired reduction in reports of fatigue and discomfort among microscope users. Occupational health nurses are ideal candidates to lead teams to accomplish meaningful health and safety goals consistent with corporate quality initiatives and strategic objectives. Copyright 2011, SLACK Incorporated.

  18. Microscopic characterization of peptide nanostructures.

    PubMed

    Mammadov, Rashad; Tekinay, Ayse B; Dana, Aykutlu; Guler, Mustafa O

    2012-02-01

    Peptide-based nanomaterials have been utilized for various applications from regenerative medicine to electronics since they provide several advantages including easy synthesis methods, numerous routes for functionalization and biomimicry of secondary structures of proteins which leads to design of self-assembling peptide molecules to form nanostructures. Microscopic characterization at nanoscale is critical to understand processes directing peptide molecules to self-assemble and identify structure-function relationship of the nanostructures. Here, fundamental studies in microscopic characterization of peptide nanostructures are discussed to provide insights in widely used microscopy tools. In this review, we will encompass characterization studies of peptide nanostructures with modern microscopes, such as TEM, SEM, AFM, and advanced optical microscopy techniques. We will also mention specimen preparation methods and describe interpretation of the images.

  19. Scanning thermal-conductivity microscope

    NASA Astrophysics Data System (ADS)

    Sarid, Dror; McCarthy, Brendan; Grover, Ranjan

    2006-02-01

    This article describes a novel implementation of an atomic force microscope that can map thermal-conductivity features across a sample with a high spatial resolution. The microscope employs a single-sided, metal-coated cantilever, which acts as a bimetallic strip together with a heating laser whose beam is focused on the cantilever's free end, on the opposite side of its tip. Subtracting the topography obtained by the unheated and heated cantilevers yields a map of thermal conductivity across the surface of a sample. The article presents (a) the theory of operation of the microscope and (b) the experimental results obtained on a silicon sample with oxide features, showing good agreement between the two.

  20. Microscope and method of use

    SciTech Connect

    Bongianni, W.L.

    1981-08-18

    A method and apparatus for electronically focusing and electronically scanning microscopic specimens are given. In the invention, visual images of even moving, living, opaque specimens can be acoustically obtained and viewed with virtually no time needed for processing (i.e., real time processing is used). And planar samples are not required. The specimens (if planar) need not be moved during scanning, although it will be desirable and possible to move or rotate nonplanar specimens (e.g., laser fusion targets) against the lens of the apparatus. No coupling fluid is needed, so specimens need not be wetted. A phase acoustic microscope is also made from the basic microscope components together with electronic mixers.

  1. Microscope and method of use

    DOEpatents

    Bongianni, Wayne L.

    1984-01-01

    A method and apparatus for electronically focusing and electronically scanning microscopic specimens are given. In the invention, visual images of even moving, living, opaque specimens can be acoustically obtained and viewed with virtually no time needed for processing (i.e., real time processing is used). And planar samples are not required. The specimens (if planar) need not be moved during scanning, although it will be desirable and possible to move or rotate nonplanar specimens (e.g., laser fusion targets) against the lens of the apparatus. No coupling fluid is needed, so specimens need not be wetted. A phase acoustic microscope is also made from the basic microscope components together with electronic mixers.

  2. Microscope and method of use

    DOEpatents

    Bongianni, W.L.

    1984-04-17

    A method and apparatus for electronically focusing and electronically scanning microscopic specimens are given. In the invention, visual images of even moving, living, opaque specimens can be acoustically obtained and viewed with virtually no time needed for processing (i.e., real time processing is used). And planar samples are not required. The specimens (if planar) need not be moved during scanning, although it will be desirable and possible to move or rotate nonplanar specimens (e.g., laser fusion targets) against the lens of the apparatus. No coupling fluid is needed, so specimens need not be wetted. A phase acoustic microscope is also made from the basic microscope components together with electronic mixers. 7 figs.

  3. Macroscopic-microscopic mass models

    SciTech Connect

    Nix, J.R.; Moller, P.

    1995-07-01

    We discuss recent developments in macroscopic-microscopic mass models, including the 1992 finite-range droplet model, the 1992 extended- Thomas-Fermi Strutinsky-integral model, and the 1994 Thomas-Fermi model, with particular emphasis on how well they extrapolate to new regions of nuclei. We also address what recent developments in macroscopic-microscopic mass models are teaching us about such physically relevant issues as the nuclear curvature energy, a new congruence energy arising from a greater-than-average overlap of neutron and proton wave functions, the nuclear incompressibility coefficient, and the coulomb redistribution energy arising from a central density depression. We conclude with a brief discussion of the recently discovered rock of metastable superheavy nuclei near {sup 272}110 that had been correctly predicted by macroscopic-microscopic models, along with a possible new tack for reaching an island near {sup 290}110 beyond our present horizon.

  4. Mosaic of Commemorative Microscope Substrate

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Written by electron beam lithography in the Microdevices Laboratory of NASA's Jet Propulsion Laboratory, this Optical Microscope substrate helps the Phoenix Mars Mission science team learn how to assemble individual microscope images into a mosaic by aligning rows of text.

    Each line is about 0.1 millimeter tall, the average thickness of a human hair. Except for the Mogensen twins, the names are of babies born and team members lost during the original development of MECA (the Microscopy, Electrochemistry and Conductivity Analyzer) for the canceled 2001 Mars lander mission. The plaque also acknowledges the MECA 2001 principal investigator, now retired.

    This image was taken by the MECA Optical Microscope on Sol 111, or the 111th day of the Phoenix mission (Sept. 16, 2008).

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by JPL, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  5. Mosaic of Commemorative Microscope Substrate

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Written by electron beam lithography in the Microdevices Laboratory of NASA's Jet Propulsion Laboratory, this Optical Microscope substrate helps the Phoenix Mars Mission science team learn how to assemble individual microscope images into a mosaic by aligning rows of text.

    Each line is about 0.1 millimeter tall, the average thickness of a human hair. Except for the Mogensen twins, the names are of babies born and team members lost during the original development of MECA (the Microscopy, Electrochemistry and Conductivity Analyzer) for the canceled 2001 Mars lander mission. The plaque also acknowledges the MECA 2001 principal investigator, now retired.

    This image was taken by the MECA Optical Microscope on Sol 111, or the 111th day of the Phoenix mission (Sept. 16, 2008).

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by JPL, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  6. Sample holder support for microscopes

    NASA Technical Reports Server (NTRS)

    Berry, Anthony (Inventor); Nerren, Billy H. (Inventor)

    1991-01-01

    A sample filter holder is disclosed for use with a microscope for holding the filter in a planar condition on the stage of the microscope so that automatic focusing of the microscope can be performed on particle samples dispersed on the filter. The holder includes a base having a well that communicates with an inlet port which is connected to a suction pump. A screen assembly is positioned within the well. The screen assembly includes a disk having a screen positioned on its top surface and secured to the disk at the peripheral edge of the screen. Small bores allow the outer surface of the screen to communicate with the well. The filter is placed on the screen and is held in a flat disposition by the suction forces.

  7. Microscopic Materials on a Magnet

    NASA Technical Reports Server (NTRS)

    2008-01-01

    These images show a comparison of the weak magnet OM7 from the Optical Microscope on NASA's Phoenix Mars Lander before (left) and after (right) soil deposition.

    The microscope took the left image during Phoenix's Sol 15 (June 10, 2008) and the right image during Sol 21 (Jun 16, 2008).

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  8. Advanced Microscopic Integrated Thermocouple Arrays

    NASA Technical Reports Server (NTRS)

    Pettigrew, Penny J.

    1999-01-01

    The purpose of this research is to develop and refine a technique for making microscopic thermocouple arrays for use in measuring the temperature gradient across a solid-liquid interface during the solidification process. Current thermocouple technology does not allow for real-time measurements across the interface due to the prohibitive size of available thermocouples. Microscopic thermocouple arrays will offer a much greater accuracy and resolution of temperature measurements across the solid-liquid interface which will lead to a better characterization of the solidification process and interface reaction which affect the properties of the resulting material.

  9. Microscopic Materials on a Magnet

    NASA Technical Reports Server (NTRS)

    2008-01-01

    These images show a comparison of the weak magnet OM7 from the Optical Microscope on NASA's Phoenix Mars Lander before (left) and after (right) soil deposition.

    The microscope took the left image during Phoenix's Sol 15 (June 10, 2008) and the right image during Sol 21 (Jun 16, 2008).

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  10. Long working distance interference microscope

    DOEpatents

    Sinclair, Michael B.; DeBoer, Maarten P.; Smith, Norman F.

    2004-04-13

    Disclosed is a long working distance interference microscope suitable for three-dimensional imaging and metrology of MEMS devices and test structures on a standard microelectronics probe station. The long working distance of 10-30 mm allows standard probes or probe cards to be used. This enables nanometer-scale 3-D height profiles of MEMS test structures to be acquired across an entire wafer. A well-matched pair of reference/sample objectives is not required, significantly reducing the cost of this microscope, as compared to a Linnik microinterferometer.

  11. Assessing various Infrared (IR) microscopic imaging techniques for post-mortem interval evaluation of human skeletal remains.

    PubMed

    Woess, Claudia; Unterberger, Seraphin Hubert; Roider, Clemens; Ritsch-Marte, Monika; Pemberger, Nadin; Cemper-Kiesslich, Jan; Hatzer-Grubwieser, Petra; Parson, Walther; Pallua, Johannes Dominikus

    2017-01-01

    Due to the influence of many environmental processes, a precise determination of the post-mortem interval (PMI) of skeletal remains is known to be very complicated. Although methods for the investigation of the PMI exist, there still remains much room for improvement. In this study the applicability of infrared (IR) microscopic imaging techniques such as reflection-, ATR- and Raman- microscopic imaging for the estimation of the PMI of human skeletal remains was tested. PMI specific features were identified and visualized by overlaying IR imaging data with morphological tissue structures obtained using light microscopy to differentiate between forensic and archaeological bone samples. ATR and reflection spectra revealed that a more prominent peak at 1042 cm-1 (an indicator for bone mineralization) was observable in archeological bone material when compared with forensic samples. Moreover, in the case of the archaeological bone material, a reduction in the levels of phospholipids, proteins, nucleic acid sugars, complex carbohydrates as well as amorphous or fully hydrated sugars was detectable at (reciprocal wavelengths/energies) between 3000 cm-1 to 2800 cm-1. Raman spectra illustrated a similar picture with less ν2PO43-at 450 cm-1 and ν4PO43- from 590 cm-1 to 584 cm-1, amide III at 1272 cm-1 and protein CH2 deformation at 1446 cm-1 in archeological bone material/samples/sources. A semi-quantitative determination of various distributions of biomolecules by chemi-maps of reflection- and ATR- methods revealed that there were less carbohydrates and complex carbohydrates as well as amorphous or fully hydrated sugars in archaeological samples compared with forensic bone samples. Raman- microscopic imaging data showed a reduction in B-type carbonate and protein α-helices after a PMI of 3 years. The calculated mineral content ratio and the organic to mineral ratio displayed that the mineral content ratio increases, while the organic to mineral ratio decreases with time

  12. Assessing various Infrared (IR) microscopic imaging techniques for post-mortem interval evaluation of human skeletal remains

    PubMed Central

    Roider, Clemens; Ritsch-Marte, Monika; Pemberger, Nadin; Cemper-Kiesslich, Jan; Hatzer-Grubwieser, Petra; Parson, Walther; Pallua, Johannes Dominikus

    2017-01-01

    Due to the influence of many environmental processes, a precise determination of the post-mortem interval (PMI) of skeletal remains is known to be very complicated. Although methods for the investigation of the PMI exist, there still remains much room for improvement. In this study the applicability of infrared (IR) microscopic imaging techniques such as reflection-, ATR- and Raman- microscopic imaging for the estimation of the PMI of human skeletal remains was tested. PMI specific features were identified and visualized by overlaying IR imaging data with morphological tissue structures obtained using light microscopy to differentiate between forensic and archaeological bone samples. ATR and reflection spectra revealed that a more prominent peak at 1042 cm-1 (an indicator for bone mineralization) was observable in archeological bone material when compared with forensic samples. Moreover, in the case of the archaeological bone material, a reduction in the levels of phospholipids, proteins, nucleic acid sugars, complex carbohydrates as well as amorphous or fully hydrated sugars was detectable at (reciprocal wavelengths/energies) between 3000 cm-1 to 2800 cm-1. Raman spectra illustrated a similar picture with less ν2PO43−at 450 cm-1 and ν4PO43− from 590 cm-1 to 584 cm-1, amide III at 1272 cm-1 and protein CH2 deformation at 1446 cm-1 in archeological bone material/samples/sources. A semi-quantitative determination of various distributions of biomolecules by chemi-maps of reflection- and ATR- methods revealed that there were less carbohydrates and complex carbohydrates as well as amorphous or fully hydrated sugars in archaeological samples compared with forensic bone samples. Raman- microscopic imaging data showed a reduction in B-type carbonate and protein α-helices after a PMI of 3 years. The calculated mineral content ratio and the organic to mineral ratio displayed that the mineral content ratio increases, while the organic to mineral ratio decreases with

  13. Reflectance Modeling

    NASA Technical Reports Server (NTRS)

    Smith, J. A. (Principal Investigator)

    1985-01-01

    The overall goal of this work has been to develop a set of computational tools and media abstractions for the terrain bidirectional reflectance problem. The modeling of soil and vegetation surfaces has been emphasized with a gradual increase in the complexity of the media geometries treated. Pragmatic problems involved in the combined modeling of soil, vegetation, and atmospheric effects have been of interest and one of the objectives has been to describe the canopy reflectance problem in a classical radiative transfer sense permitting easier inclusion of our work by other workers in the radiative transfer field.

  14. Phase resolved and coherence gated en face reflection imaging of multilayered embryonal carcinoma cells

    NASA Astrophysics Data System (ADS)

    Yamauchi, Toyohiko; Fukami, Tadashi; Iwai, Hidenao; Yamashita, Yutaka

    2012-03-01

    Embryonal carcinoma (EC) cells, which are cell lines derived from teratocarcinomas, have characteristics in common with stem cells and differentiate into many kinds of functional cells. Similar to embryonic stem (ES) cells, undifferentiated EC cells form multi-layered spheroids. In order to visualize the three-dimensional structure of multilayered EC cells without labeling, we employed full-field interference microscopy with the aid of a low-coherence quantitative phase microscope, which is a reflection-type interference microscope employing the digital holographic technique with a low-coherent light source. Owing to the low-coherency of the light-source (halogen lamp), only the light reflected from reflective surface at a specific sectioning height generates an interference image on the CCD camera. P19CL6 EC cells, derived from mouse teratocarcinomas, formed spheroids that are about 50 to 200 micrometers in diameter. Since the height of each cell is around 10 micrometers, it is assumed that each spheroid has 5 to 20 cell layers. The P19CL6 spheroids were imaged in an upright configuration and the horizontally sectioned reflection images of the sample were obtained by sequentially and vertically scanning the zero-path-length height. Our results show the threedimensional structure of the spheroids, in which plasma and nuclear membranes were distinguishably imaged. The results imply that our technique is further capable of imaging induced pluripotent stem (iPS) cells for the assessment of cell properties including their pluripotency.

  15. Teaching Optics to Biology Students Through Constructing a Light Microscope

    NASA Astrophysics Data System (ADS)

    Ross, Jennifer

    2015-03-01

    The microscope is familiar to many disciplines, including physics, materials science, chemistry, and the life sciences. It demonstrates fundamental aspects of ray and wave optics, making it an ideal system to help educate students in the basic concepts of optics and in measurement principles and techniques. We present an experimental system developed to teach students the basics of ray and wave optics. The students design, build, and test a light microscope made from optics components. We describe the equipment and the basic measurements that students can perform to develop experimental techniques to understand optics principles. Students measure the magnification and test the resolution of the microscope. The system is open and versatile to allow advanced projects such as epi-fluorescence, total internal reflection fluorescence, and optical trapping. We have used this equipment in an optics course, an advanced laboratory course, and graduate-level training modules.

  16. Switch on Micro*scope!

    ERIC Educational Resources Information Center

    Roland, Sarah; Bahr, Michele; Olendzenski, Lorraine; Patterson, David J.

    2005-01-01

    Scientists at the Marine Biological Laboratory in Woods Hole, Massachusetts, have created micro*scope, a free, searchable knowledge environment for exploring the microbial world. Microbiology can easily be incorporated into the curriculum, because microbial communities are easy to access. Organisms grow quickly, making certain arrays of…

  17. Curriculum Guidelines for Microscopic Anatomy.

    ERIC Educational Resources Information Center

    Journal of Dental Education, 1993

    1993-01-01

    The American Association of Dental Schools' guidelines for curricula in microscopic anatomy offer an overview of the histology curriculum, note primary educational goals, outline specific content for general and oral histology, suggest prerequisites, and make recommendations for sequencing. Appropriate faculty and facilities are also suggested.…

  18. High-resolution electron microscope

    NASA Technical Reports Server (NTRS)

    Nathan, R.

    1977-01-01

    Employing scanning transmission electron microscope as interferometer, relative phases of diffraction maximums can be determined by analysis of dark field images. Synthetic aperture technique and Fourier-transform computer processing of amplitude and phase information provide high resolution images at approximately one angstrom.

  19. Nature Study with the Microscope.

    ERIC Educational Resources Information Center

    Sollberger, Dwight E.

    1991-01-01

    Identifies specific instruction difficulties, potential problems, solutions, and activities for successful use of microscopes in the classroom. Procedures are outlined for guiding students in creating their own slides with monocotyledon and dicotyledon stems, fern spores, stomata, lichens, and red onions. (MCO)

  20. Chasing Meteors With a Microscope.

    ERIC Educational Resources Information Center

    Jones, Richard C.

    1993-01-01

    Describes types of meteors and micrometeorites that enter the Earth's atmosphere. Presents an activity where students collect micrometeorites with a strip of tape in an undisturbed outdoor area. After 24 hours, they examine the tape by sandwiching it between 2 glass slides and view through a microscope at 100X. (PR)

  1. Switch on Micro*scope!

    ERIC Educational Resources Information Center

    Roland, Sarah; Bahr, Michele; Olendzenski, Lorraine; Patterson, David J.

    2005-01-01

    Scientists at the Marine Biological Laboratory in Woods Hole, Massachusetts, have created micro*scope, a free, searchable knowledge environment for exploring the microbial world. Microbiology can easily be incorporated into the curriculum, because microbial communities are easy to access. Organisms grow quickly, making certain arrays of…

  2. Nature Study with the Microscope.

    ERIC Educational Resources Information Center

    Sollberger, Dwight E.

    1991-01-01

    Identifies specific instruction difficulties, potential problems, solutions, and activities for successful use of microscopes in the classroom. Procedures are outlined for guiding students in creating their own slides with monocotyledon and dicotyledon stems, fern spores, stomata, lichens, and red onions. (MCO)

  3. Chasing Meteors With a Microscope.

    ERIC Educational Resources Information Center

    Jones, Richard C.

    1993-01-01

    Describes types of meteors and micrometeorites that enter the Earth's atmosphere. Presents an activity where students collect micrometeorites with a strip of tape in an undisturbed outdoor area. After 24 hours, they examine the tape by sandwiching it between 2 glass slides and view through a microscope at 100X. (PR)

  4. The Biggest Microscopic Image Ever

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is a mosaic of four individual frames taken by the microscopic imager that have been very carefully stitched together to reveal the entire 5-centimeter-diameter (almost 2-inch) hole left on the rock dubbed 'Humphrey.' The holes were created by the Mars Exploration Rover Spirit's rock abrasion tool. The mosaic, created on March 7, 2004, is the first of its kind of an abraded surface on Mars, and gave scientists their first ever microscopic imager view of the entire drilled area. While it is easy for the panoramic camera and the navigation cameras to fit an area this size into their field of view, the microscopic imager can only capture a portion of the ground area with each image.

    Scientists are interested in many of the small features on 'Humphrey' uncovered by the rock abrasion tool and made visible by the microscopic imager. The sinuous veins within the rock could be evidence that water was trickling through the material while it was deep underground, whereas the dark 'age spots' in the center of the hole may be crystals of the mineral olivine.

  5. Scanning tunneling microscope nanoetching method

    DOEpatents

    Li, Yun-Zhong; Reifenberger, Ronald G.; Andres, Ronald P.

    1990-01-01

    A method is described for forming uniform nanometer sized depressions on the surface of a conducting substrate. A tunneling tip is used to apply tunneling current density sufficient to vaporize a localized area of the substrate surface. The resulting depressions or craters in the substrate surface can be formed in information encoding patterns readable with a scanning tunneling microscope.

  6. Curriculum Guidelines for Microscopic Anatomy.

    ERIC Educational Resources Information Center

    Journal of Dental Education, 1993

    1993-01-01

    The American Association of Dental Schools' guidelines for curricula in microscopic anatomy offer an overview of the histology curriculum, note primary educational goals, outline specific content for general and oral histology, suggest prerequisites, and make recommendations for sequencing. Appropriate faculty and facilities are also suggested.…

  7. The microscope in the hatchery

    USGS Publications Warehouse

    Fish, F.F.

    1935-01-01

    Without the aid of the microscope, it is safe to assume that fish Culture would now stand exactly where it did seventy-five years ago when methods of artificial fertilization were first applied. It is also safe to assume that the results from fish culture would be as unsatisfactory as they were at that time when the fishery resources were steadily declining in spite of the increased liberation of advanced fry from the hatcheries. During the past few years the microscope has saved millions of fish in our hatcheries which otherwise would have been sacrificed to disease. Moreover, the microscope has permitted all of the recent work in selective breeding, nutritional requirements, and disease control. This work marks most of the progress fish culture has made during the past twenty-five years. This progress forms the first definite step away from the old system of hatching and distributing fish, a system which was founded by the ancient Chinese. The microscope has been the key which enabled the fish culturist to solve the riddle of success which has stood, unanswered, for 2,500 years.

  8. The Biggest Microscopic Image Ever

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is a mosaic of four individual frames taken by the microscopic imager that have been very carefully stitched together to reveal the entire 5-centimeter-diameter (almost 2-inch) hole left on the rock dubbed 'Humphrey.' The holes were created by the Mars Exploration Rover Spirit's rock abrasion tool. The mosaic, created on March 7, 2004, is the first of its kind of an abraded surface on Mars, and gave scientists their first ever microscopic imager view of the entire drilled area. While it is easy for the panoramic camera and the navigation cameras to fit an area this size into their field of view, the microscopic imager can only capture a portion of the ground area with each image.

    Scientists are interested in many of the small features on 'Humphrey' uncovered by the rock abrasion tool and made visible by the microscopic imager. The sinuous veins within the rock could be evidence that water was trickling through the material while it was deep underground, whereas the dark 'age spots' in the center of the hole may be crystals of the mineral olivine.

  9. Microscopic rates of peptide-phospholipid bilayer interactions from single-molecule residence times.

    PubMed

    Myers, Grant A; Gacek, Daniel A; Peterson, Eric M; Fox, Christopher B; Harris, Joel M

    2012-12-05

    The binding of glucagon-like peptide-1 (GLP-1) to a planar phospholipid bilayer is measured using single-molecule total internal reflection fluorescence microscopy. From several reports in the literature, GLP-1 has been shown to be a random coil in free solution, adopting a folded, α-helix conformation when intercalated into membrane environments. Single-molecule fluorescence measurements of GLP-1 binding to supported lipid bilayers show evidence of two populations of membrane-associated molecules having different residence times, suggesting weakly adsorbed peptides and strongly bound peptides in the lipid bilayer. The path to and from a strongly bound (folded, intercalated) state would likely include an adsorbed state as an intermediate, so that the resulting kinetics would correspond to a consecutive first-order reversible three-state model. In this work, the relationships between measured single-molecule residence times and the microscopic rates in a three-state kinetic model are derived and used to interpret the binding of GLP-1 to a supported lipid bilayer. The system of differential equations associated with the proposed consecutive-three state kinetics scheme is solved, and the solution is applied to interpret histograms of single-molecule, GLP-1 residence times in terms of the microscopic rates in the sequential two-step model. These microscopic rates are used to estimate the free energy barrier to adsorption, the fraction of peptides adsorbing to the membrane surface that successfully intercalate in the bilayer, the lifetime of inserted peptides in the membrane, and the free energy change of insertion into the lipid bilayer from the adsorbed state. The transition from a random coil in solution to a folded state in a membrane has been recognized as a common motif for insertion of membrane active peptides. Therefore, the relationships developed here could have wide application to the kinetic analysis of peptide-membrane interactions.

  10. Microscope sterility during spine surgery.

    PubMed

    Bible, Jesse E; O'Neill, Kevin R; Crosby, Colin G; Schoenecker, Jonathan G; McGirt, Matthew J; Devin, Clinton J

    2012-04-01

    Prospective study. Assess the contamination rates of sterile microscope drapes after spine surgery. The use of the operating microscope has become more prevalent in certain spine procedures, providing superior magnification, visualization, and illumination of the operative field. However, it may represent an additional source of bacterial contamination and increase the risk of developing a postoperative infection. This study included 25 surgical spine cases performed by a single spine surgeon that required the use of the operative microscope. Sterile culture swabs were used to obtain samples from 7 defined locations on the microscope drape after its use during the operation. The undraped technician's console was sampled in each case as a positive control, and an additional 25 microscope drapes were swabbed immediately after they were applied to the microscope to obtain negative controls. Swab samples were assessed for bacterial growth on 5% sheep blood Columbia agar plates using a semiquantitative technique. No growth was observed on any of the 25 negative control drapes. In contrast, 100% of preoperative and 96% of postoperative positive controls demonstrated obvious contamination. In the postoperative group, all 7 sites of evaluation were found to be contaminated with rates of 12% to 44%. Four of the 7 evaluated locations were found to have significant contamination rates compared with negative controls, including the shafts of the optic eyepieces on the main surgeon side (24%, P = 0.022), "forehead" portion on both the main surgeon (24%, P = 0.022) and assistant sides (28%, P = 0.010), and "overhead" portion of the drape (44%, P = 0.0002). Bacterial contamination of the operative microscope was found to be significant after spine surgery. Contamination was more common around the optic eyepieces, likely due to inadvertent touching of unsterile portions. Similarly, all regions above the eyepieces also have a propensity for contamination because of unknown contact

  11. Compressive microscopic imaging with "positive-negative" light modulation

    NASA Astrophysics Data System (ADS)

    Yu, Wen-Kai; Yao, Xu-Ri; Liu, Xue-Feng; Lan, Ruo-Ming; Wu, Ling-An; Zhai, Guang-Jie; Zhao, Qing

    2016-07-01

    An experiment on compressive microscopic imaging with single-pixel detector and single-arm has been performed on the basis of ;positive-negative; (differential) light modulation of a digital micromirror device (DMD). A magnified image of micron-sized objects illuminated by the microscope's own incandescent lamp has been successfully acquired. The image quality is improved by one more orders of magnitude compared with that obtained by conventional single-pixel imaging scheme with normal modulation using the same sampling rate, and moreover, the system is robust against the instability of light source and may be applied to very weak light condition. Its nature and the analysis of noise sources is discussed deeply. The realization of this technique represents a big step to the practical applications of compressive microscopic imaging in the fields of biology and materials science.

  12. Experiments on terahertz 3D scanning microscopic imaging

    NASA Astrophysics Data System (ADS)

    Zhou, Yi; Li, Qi

    2016-10-01

    Compared with the visible light and infrared, terahertz (THz) radiation can penetrate nonpolar and nonmetallic materials. There are many studies on the THz coaxial transmission confocal microscopy currently. But few researches on the THz dual-axis reflective confocal microscopy were reported. In this paper, we utilized a dual-axis reflective confocal scanning microscope working at 2.52 THz. In contrast with the THz coaxial transmission confocal microscope, the microscope adopted in this paper can attain higher axial resolution at the expense of reduced lateral resolution, revealing more satisfying 3D imaging capability. Objects such as Chinese characters "Zhong-Hua" written in paper with a pencil and a combined sheet metal which has three layers were scanned. The experimental results indicate that the system can extract two Chinese characters "Zhong," "Hua" or three layers of the combined sheet metal. It can be predicted that the microscope can be applied to biology, medicine and other fields in the future due to its favorable 3D imaging capability.

  13. Neutron reflectivity

    NASA Astrophysics Data System (ADS)

    Cousin, Fabrice; Menelle, Alain

    2015-10-01

    The specular neutron reflectivity is a technique enabling the measurement of neutron scattering length density profile perpendicular to the plane of a surface or an interface, and thereby the profile of chemical composition. The characteristic sizes that are probed range from around 5 Å up 5000 Å. It is a scattering technique that averages information on the entire surface and it is therefore not possible to obtain information within the plane of the interface. The specific properties of neutrons (possibility of tuning the contrast by isotopic substitution, sensitivity to magnetism, negligible absorption, low energy of the incident neutrons) makes it particularly interesting in the fields of soft matter, biophysics and magnetic thin films. This course is a basic introduction to the technique and does not address the magnetic reflectivity. It is composed of three parts describing respectively its principle and its formalism, the experimental aspects of the method (spectrometers, samples) and two examples related to the materials for energy.

  14. Confocal scanning beam laser microscope/macroscope: applications in fluorescence

    NASA Astrophysics Data System (ADS)

    Dixon, Arthur E.; Damaskinos, Savvas; Ribes, Alfonso

    1996-03-01

    A new confocal scanning beam laser microscope/macroscope is described that combines the rapid scan of a scanning beam laser microscope with the large specimen capability of a scanning stage microscope. This instrument combines an infinity-corrected confocal scanning laser microscope with a scanning laser macroscope that uses a telecentric f*(Theta) laser scan lens to produce a confocal imaging system with a resolution of 0.25 microns at a field of view of 25 microns and 5 microns at a field of view of 75,000 microns. The frame rate is 5 seconds per frame for a 512 by 512 pixel image, and 25 seconds for a 2048 by 2048 pixel image. Applications in fluorescence are discussed that focus on two important advantages of the instrument over a confocal scanning laser microscope: an extremely wide range of magnification, and the ability to image very large specimens. Examples are presented of fluorescence and reflected-light images of high quality printing, fluorescence images of latent fingerprints, packaging foam, and confocal autofluorescence images of a cricket.

  15. Development of X-ray imaging microscopes for LMJ

    NASA Astrophysics Data System (ADS)

    Troussel, Philippe; Rosch, Rudolph; Reverdin, Charles; Soullié, Gérard; Boutin, Jean Yves; Marmoret, Rémy; Richard, André; Bridou, Francoise; Delmotte, Franck

    2010-11-01

    For the future Laser Megajoules French facility (LMJ), our laboratory develops time-resolved X-ray Imaging systems to diagnose laser produced plasma. In this presentation, we describe the design of these imagers which combine grazing X-ray microscope and camera. A first set of three imaging diagnostics will give basic measurements during all the life of the facility : two twelve-image microscopes focalize X-rays from the target on a framing camera. The third one produces an image on a streak camera. These microscopes also contain refractive lenses to extend the spectral range up to 15 keV. A second set of diagnostics will consist of advanced high resolution X-ray imaging systems. Imaging studies performed with a microscope composed of three concave toroidal mirrors are presented. This microscope, working at 0.6 degrees grazing incidence, has a focal length longer than 80 cm. About the imaging performances, we have achieved a spatial resolution of about 6 microns for the sagittal dimension and around 10 microns for the tangential dimension within a field of 1 mm. To increase the bandwidth of reflectivity of all these mirrors until 10 keV, multilayer coatings have been deposited.

  16. Versatile multispectral microscope based on light emitting diodes

    NASA Astrophysics Data System (ADS)

    Brydegaard, Mikkel; Merdasa, Aboma; Jayaweera, Hiran; Ålebring, Jens; Svanberg, Sune

    2011-12-01

    We describe the development of a novel multispectral microscope, based on light-emitting diodes, capable of acquiring megapixel images in thirteen spectral bands from the ultraviolet to the near infrared. The system captures images and spectra in transmittance, reflectance, and scattering modes. We present as examples of applications ground truth measurements for remote sensing and parasitology diagnostics. The system is a general purpose scientific instrument that could be used to develop dedicated simplified instruments with optimal bands and mode selection.

  17. Compact scanning-force microscope using a laser diode

    NASA Astrophysics Data System (ADS)

    Sarid, Dror; Iams, Doug; Weissenberger, Volker; Bell, L. Stephen

    1988-12-01

    The paper describes the operation of a compact scanning-force microscope in which the gradient of force acting on a vibrating tip is monitored by a diode laser and its integrated photodiode. The system does not require reflecting or focusing elements or complicated electronics. Experimental results using this system with magnetic domains on a magnetooptic storage medium attest to the feasibility of this concept.

  18. A mini-microscope for in situ monitoring of cells.

    PubMed

    Kim, Sang Bok; Koo, Kyo-in; Bae, Hojae; Dokmeci, Mehmet R; Hamilton, Geraldine A; Bahinski, Anthony; Kim, Sun Min; Ingber, Donald E; Khademhosseini, Ali

    2012-10-21

    A mini-microscope was developed for in situ monitoring of cells by modifying off-the-shelf components of a commercial webcam. The mini-microscope consists of a CMOS imaging module, a small plastic lens and a white LED illumination source. The CMOS imaging module was connected to a laptop computer through a USB port for image acquisition and analysis. Due to its compact size, 8 × 10 × 9 cm, the present microscope is portable and can easily fit inside a conventional incubator, and enables real-time monitoring of cellular behaviour. Moreover, the mini-microscope can be used for imaging cells in conventional cell culture flasks, such as Petri dishes and multi-well plates. To demonstrate the operation of the mini-microscope, we monitored the cellular migration of mouse 3T3 fibroblasts in a scratch assay in medium containing three different concentrations of fetal bovine serum (5, 10, and 20%) and demonstrated differential responses depending on serum levels. In addition, we seeded embryonic stem cells inside poly(ethylene glycol) microwells and monitored the formation of stem cell aggregates in real time using the mini-microscope. Furthermore, we also combined a lab-on-a-chip microfluidic device for microdroplet generation and analysis with the mini-microscope and observed the formation of droplets under different flow conditions. Given its cost effectiveness, robust imaging and portability, the presented platform may be useful for a range of applications for real-time cellular imaging using lab-on-a-chip devices at low cost.

  19. A hyperspectral scanning microscope system for phenomenology support

    NASA Astrophysics Data System (ADS)

    Lucey, Paul G.; Norman, Jessica; Crites, Sarah T.

    2017-05-01

    Three hyperspectral imaging systems have been implemented as microscopic hyperspectral imagers to support phenomenology studies at high spatial resolution. Wavelength ranges are VNIR (500 to 1000 nm), SWIR (1000 nm to 2500 nm) and LWIR (7 to 14 microns). The spatial resolution of the system at all wavelengths is 30 microns and covers a field of view of 8x30 mm. Samples are illuminated by rings of halogen lights and IR emitters for reflectance measurements and at thermal wavelengths can also be measured in thermal emission. Data are calibrated by scans of gold or Spectralon reflectance standards, and a flat plate blackbody for thermal emission measurements.

  20. Hyperbaric Hydrothermal Atomic Force Microscope

    DOEpatents

    Knauss, Kevin G.; Boro, Carl O.; Higgins, Steven R.; Eggleston, Carrick M.

    2003-07-01

    A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

  1. Nanocarpets for Trapping Microscopic Particles

    NASA Technical Reports Server (NTRS)

    Noca, Flavio; Chen, Fei; Hunt, Brian; Bronikowski, Michael; Hoenk, Michael; Kowalczyk, Robert; Choi, Daniel

    2004-01-01

    Nanocarpets that is, carpets of carbon nanotubes are undergoing development as means of trapping microscopic particles for scientific analysis. Examples of such particles include inorganic particles, pollen, bacteria, and spores. Nanocarpets can be characterized as scaled-down versions of ordinary macroscopic floor carpets, which trap dust and other particulate matter, albeit not purposefully. Nanocarpets can also be characterized as mimicking both the structure and the particle-trapping behavior of ciliated lung epithelia, the carbon nanotubes being analogous to cilia. Carbon nanotubes can easily be chemically functionalized for selective trapping of specific particles of interest. One could, alternatively, use such other three-dimensionally-structured materials as aerogels and activated carbon for the purposeful trapping of microscopic particles. However, nanocarpets offer important advantages over these alternative materials: (1) Nanocarpets are amenable to nonintrusive probing by optical means; and (2) Nanocarpets offer greater surface-to-volume ratios.

  2. Shear Brillouin light scattering microscope

    PubMed Central

    Kim, Moonseok; Besner, Sebastien; Ramier, Antoine; Kwok, Sheldon J. J.; An, Jeesoo; Scarcelli, Giuliano; Yun, Seok Hyun

    2016-01-01

    Brillouin spectroscopy has been used to characterize shear acoustic phonons in materials. However, conventional instruments had slow acquisition times over 10 min per 1 mW of input optical power, and they required two objective lenses to form a 90° scattering geometry necessary for polarization coupling by shear phonons. Here, we demonstrate a confocal Brillouin microscope capable of detecting both shear and longitudinal phonons with improved speeds and with a single objective lens. Brillouin scattering spectra were measured from polycarbonate, fused quartz, and borosilicate in 1-10 s at an optical power level of 10 mW. The elastic constants, phonon mean free path and the ratio of the Pockels coefficients were determined at microscopic resolution. PMID:26832263

  3. Mars Life? - Microscopic Tubular Structures

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This electron microscope image shows tubular structures of likely Martian origin. These structures are very similar in size and shape to extremely tiny microfossils found in some Earth rocks. This photograph is part of a report by a NASA research team published in the Aug. 16, 1996, issue of the journal Science. A two-year investigation by the team found organic molecules, mineral features characteristic of biological activity and possible microscopic fossils such as these inside of an ancient Martian rock that fell to Earth as a meteorite. The largest possible fossils are less than 1/100th the diameter of a human hair in size while most are ten times smaller.

  4. Hyperbaric hydrothermal atomic force microscope

    DOEpatents

    Knauss, Kevin G.; Boro, Carl O.; Higgins, Steven R.; Eggleston, Carrick M.

    2002-01-01

    A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

  5. Terahertz transmission vs reflection imaging and model-based characterization for excised breast carcinomas.

    PubMed

    Bowman, Tyler; El-Shenawee, Magda; Campbell, Lucas K

    2016-09-01

    This work presents experimental and analytical comparison of terahertz transmission and reflection imaging modes for assessing breast carcinoma in excised paraffin-embedded human breast tissue. Modeling for both transmission and reflection imaging is developed. The refractive index and absorption coefficient of the tissue samples are obtained. The reflection measurements taken at the system's fixed oblique angle of 30° are shown to be a hybridization of TE and TM modes. The models are validated with transmission spectroscopy at fixed points on fresh bovine muscle and fat tissues. Images based on the calculated absorption coefficient and index of refraction of bovine tissue are successfully compared with the terahertz magnitude and phase measured in the reflection mode. The validated techniques are extended to 20 and 30 μm slices of fixed human lobular carcinoma and infiltrating ductal carcinoma mounted on polystyrene microscope slides in order to investigate the terahertz differentiation of the carcinoma with non-cancerous tissue. Both transmission and reflection imaging show clear differentiation in carcinoma versus healthy tissue. However, when using the reflection mode, in the calculation of the thin tissue properties, the absorption is shown to be sensitive to small phase variations that arise due to deviations in slide and tissue thickness and non-ideal tissue adhesion. On the other hand, the results show that the transmission mode is much less sensitive to these phase variations. The results also demonstrate that reflection imaging provides higher resolution and more clear margins between cancerous and fibroglandular regions, cancerous and fatty regions, and fibroglandular and fatty tissue regions. In addition, more features consistent with high power pathology images are exhibited in the reflection mode images.

  6. Terahertz transmission vs reflection imaging and model-based characterization for excised breast carcinomas

    PubMed Central

    Bowman, Tyler; El-Shenawee, Magda; Campbell, Lucas K.

    2016-01-01

    This work presents experimental and analytical comparison of terahertz transmission and reflection imaging modes for assessing breast carcinoma in excised paraffin-embedded human breast tissue. Modeling for both transmission and reflection imaging is developed. The refractive index and absorption coefficient of the tissue samples are obtained. The reflection measurements taken at the system’s fixed oblique angle of 30° are shown to be a hybridization of TE and TM modes. The models are validated with transmission spectroscopy at fixed points on fresh bovine muscle and fat tissues. Images based on the calculated absorption coefficient and index of refraction of bovine tissue are successfully compared with the terahertz magnitude and phase measured in the reflection mode. The validated techniques are extended to 20 and 30 μm slices of fixed human lobular carcinoma and infiltrating ductal carcinoma mounted on polystyrene microscope slides in order to investigate the terahertz differentiation of the carcinoma with non-cancerous tissue. Both transmission and reflection imaging show clear differentiation in carcinoma versus healthy tissue. However, when using the reflection mode, in the calculation of the thin tissue properties, the absorption is shown to be sensitive to small phase variations that arise due to deviations in slide and tissue thickness and non-ideal tissue adhesion. On the other hand, the results show that the transmission mode is much less sensitive to these phase variations. The results also demonstrate that reflection imaging provides higher resolution and more clear margins between cancerous and fibroglandular regions, cancerous and fatty regions, and fibroglandular and fatty tissue regions. In addition, more features consistent with high power pathology images are exhibited in the reflection mode images. PMID:27699136

  7. Opening a Window into Living Tissue: Histopathologic Features of Confocal Microscopic Findings in Skin Tumors.

    PubMed

    Tavoloni Braga, Juliana Casagrande; de Paula Ramos Castro, Raquel; Moraes Pinto Blumetti, Tatiana Cristina; Rocha Mendes, Fernanda Berti; Arêas de Souza Lima Beltrame Ferreira, Juliana; Rezze, Gisele Gargantini

    2016-10-01

    The knowledge of histopathology and in vivo reflectance confocal microscopy correlation has several potential applications. Reflectance confocal microscopy can be performed in all skin tumors, and in this article, the most common histopathologic features of confocal microscopic findings in melanocytic skin tumors and nonmelanocytic skin tumors are described. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Apparatus Would Stain Microscope Slides

    NASA Technical Reports Server (NTRS)

    Breeding, James D.

    1993-01-01

    Proposed apparatus meters specific amounts of fluid out of containers at specific times to stain microscope slides. Intended specifically for semiautomated staining of microbiological and hematological samples in microgravity, leakproof apparatus used in other environments in which technicians have little time to allocate to staining procedures and/or exposure to toxic staining agents or to micro-organisms to be stained hazardous. Apparatus adapted to perform almost any staining procedure and accommodates multiple staining reagents, useful for small or remote clinical laboratories.

  9. Microscopic Description of Scission Configurations

    SciTech Connect

    Dubray, N.; Goutte, H.; Berger, J. F.

    2007-02-26

    Properties of 226Th, 256Fm, 258Fm and 260Fm nuclei in the scission region are described using a full-microscopic Hartree-Fock-Bogoliubov approach with the effective Gogny nucleon-nucleon interaction. In a first step, the Potential Energy Surfaces are computed in the (q 20, q30) plane, the scission lines are found, fulfilling a given criterion on the density in the nuclear neck. Finally a few properties of the fragments along this line are presented.

  10. Apparatus Would Stain Microscope Slides

    NASA Technical Reports Server (NTRS)

    Breeding, James D.

    1993-01-01

    Proposed apparatus meters specific amounts of fluid out of containers at specific times to stain microscope slides. Intended specifically for semiautomated staining of microbiological and hematological samples in microgravity, leakproof apparatus used in other environments in which technicians have little time to allocate to staining procedures and/or exposure to toxic staining agents or to micro-organisms to be stained hazardous. Apparatus adapted to perform almost any staining procedure and accommodates multiple staining reagents, useful for small or remote clinical laboratories.

  11. Optical Analysis of Microscope Images

    NASA Astrophysics Data System (ADS)

    Biles, Jonathan R.

    Microscope images were analyzed with coherent and incoherent light using analog optical techniques. These techniques were found to be useful for analyzing large numbers of nonsymbolic, statistical microscope images. In the first part phase coherent transparencies having 20-100 human multiple myeloma nuclei were simultaneously photographed at 100 power magnification using high resolution holographic film developed to high contrast. An optical transform was obtained by focussing the laser onto each nuclear image and allowing the diffracted light to propagate onto a one dimensional photosensor array. This method reduced the data to the position of the first two intensity minima and the intensity of successive maxima. These values were utilized to estimate the four most important cancer detection clues of nuclear size, shape, darkness, and chromatin texture. In the second part, the geometric and holographic methods of phase incoherent optical processing were investigated for pattern recognition of real-time, diffuse microscope images. The theory and implementation of these processors was discussed in view of their mutual problems of dimness, image bias, and detector resolution. The dimness problem was solved by either using a holographic correlator or a speckle free laser microscope. The latter was built using a spinning tilted mirror which caused the speckle to change so quickly that it averaged out during the exposure. To solve the bias problem low image bias templates were generated by four techniques: microphotography of samples, creation of typical shapes by computer graphics editor, transmission holography of photoplates of samples, and by spatially coherent color image bias removal. The first of these templates was used to perform correlations with bacteria images. The aperture bias was successfully removed from the correlation with a video frame subtractor. To overcome the limited detector resolution it is necessary to discover some analog nonlinear intensity

  12. One-Angstrom microscope update

    SciTech Connect

    O'Keefe, Michael A.

    1999-04-04

    The One-Angstrom Microscope project has attained its goal, and is now producing images down to 1 Angstrom resolution. We have demonstrated transmission electron microscopy of defect structures down to a resolution of 1.1 Angstrom, with evidence that 0.89 Angstrom will be possible. This level of resolution will soon be made available to all those NCEM users who have a requirement for sub-Angstrom resolution.

  13. Duties to Extraterrestrial Microscopic Organisms

    NASA Astrophysics Data System (ADS)

    Cockell, C. S.

    Formulating a normative axiology for the treatment of extraterrestrial microscopic organisms, should they ever be found, requires an extension of environmental ethics to beyond the Earth. Using an ethical framework for the treatment of terrestrial micro-organisms, this paper elaborates a similar ethic for the treatment of extraterrestrial microscopic organisms. An ethic of `teloempathy' allows for the moral considerability of any organism that has `interests', based on rudimentary qualities of conativism, and therefore allows for an identical treatment of all life, related or not related to life on Earth. Although, according to this ethic, individual extraterrestrial microscopic organisms have a good of their own and even `rights', at this level the ethic can only be theoretical, allowing for the inevitable destruction of many individual organisms during the course of human exploratory missions, similarly to the daily destruction of microbes by humans on Earth. A holistic teloempathy, an operative ethic, not only provides a framework for human exploration, but it also has important implications for planetary protection and proposals to implement planetary-scale atmospheric alterations on other bodies. Even prior to the discovery of extraterrestrial life, or the discovery of a complete absence of such life, this exercise yields important insights into the moral philosophy that guides our treatment of terrestrial micro-organisms.

  14. Compact Microscope Imaging System Developed

    NASA Technical Reports Server (NTRS)

    McDowell, Mark

    2001-01-01

    The Compact Microscope Imaging System (CMIS) is a diagnostic tool with intelligent controls for use in space, industrial, medical, and security applications. The CMIS can be used in situ with a minimum amount of user intervention. This system, which was developed at the NASA Glenn Research Center, can scan, find areas of interest, focus, and acquire images automatically. Large numbers of multiple cell experiments require microscopy for in situ observations; this is only feasible with compact microscope systems. CMIS is a miniature machine vision system that combines intelligent image processing with remote control capabilities. The software also has a user-friendly interface that can be used independently of the hardware for post-experiment analysis. CMIS has potential commercial uses in the automated online inspection of precision parts, medical imaging, security industry (examination of currency in automated teller machines and fingerprint identification in secure entry locks), environmental industry (automated examination of soil/water samples), biomedical field (automated blood/cell analysis), and microscopy community. CMIS will improve research in several ways: It will expand the capabilities of MSD experiments utilizing microscope technology. It may be used in lunar and Martian experiments (Rover Robot). Because of its reduced size, it will enable experiments that were not feasible previously. It may be incorporated into existing shuttle orbiter and space station experiments, including glove-box-sized experiments as well as ground-based experiments.

  15. Microscope Image of Scavenged Particles

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image from NASA's Phoenix Mars Lander's Optical Microscope shows a strongly magnetic surface which has scavenged particles from within the microscope enclosure before a sample delivery from the lander's Robotic Arm. The particles correspond to the larger grains seen in fine orange material that makes up most of the soil at the Phoenix site. They vary in color, but are of similar size, about one-tenth of a millimeter.

    As the microscope's sample wheel moved during operation, these particles also shifted, clearing a thin layer of the finer orange particles that have also been collected. Together with the previous image, this shows that the larger grains are much more magnetic than the fine orange particles with a much larger volume of the grains being collected by the magnet. The image is 2 milimeters across.

    It is speculated that the orange material particles are a weathering product from the larger grains, with the weathering process both causing a color change and a loss of magnetism.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by JPL, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  16. Scanned probe microscope for biological applications

    NASA Astrophysics Data System (ADS)

    Baiburin, Vil B.; Konnov, Nikolai P.; Shcherbakov, Anatolyi A.; Malakhaeva, Alina N.; Zadnova, Svetlana P.; Volkov, Yuri P.

    1997-12-01

    In our biophysical laboratory has been developed a new scanned probe microscope (SPM) for biological application. The SPM allows to investigate a biological samples' surface by means of three different near field microscopes: scanning tunneling microscope (STM), atomic force microscope (AFM) and near field scanning optical microscope (NSOM). The SPM is very rigid and can be operated in ordinary laboratory without any vibration isolation. The scanning area of the microscope is about 10 by 10 micrometers. Some different biological objects were visualized by means of the SPM viz. bacteria (E. Coli, plague, cholera, staphylococcus), macromolecules (DNA, plague proteins) and phage (T2).

  17. Versatile microscope-coupled high-intensity pulsed light source for high-speed cine photomicrography of microactuators

    NASA Astrophysics Data System (ADS)

    Krehl, Peter; Engemann, Stephan; Rembe, Christian; Hofer, Eberhard P.

    1997-05-01

    A compact high-intensity pulsed light source has been developed in order to match a microdynamic test facility for high-speed motion analysis of micromechanical components. The test stand encompasses a universal microscope Zeiss Axioplan, the new light source and an electronic ultra high- speed multiple framing camera Hadland Imacon 468. The light source consists of a narrow cylindrical Xe-filled discharge tube, thus providing a locally stable emission. Since the small-size flashlamp easily fits into a standard microscope lamphousing, it allows to maintain the advantages of Koehler illumination as well as switching to other types of lamphousings. The flash tube is operated via an artificial asymmetric transmission line and delivers a square light pulse with a flash duration of 110 microsecond(s) FWHM and a peak intensity of 50 Med. The light source illuminates the object uniformly within the interesting time window; image shuttering is provided in the camera by gated micro-channel- plate intensifiers. To test the efficiency of the total system for various standard visualization methods (transmitted light, reflected light and differential interference contrast), microscopic still images have been taken at magnification up to 500X and with exposure times down to 10 ns. In addition, two microscopic darkfield methods which provide a high contrast but a low light intensity of the image, have been selected to test their applicability down to an exposure time of 100 ns. Two examples for real-time cinematography of high-speed phenomena in microactuators are shown: the bouncing behavior of an electro-magnetic microrelay and the bubble/jet formation of a thermal ink jet printhead.

  18. The Infrared Microscope - A Versatile And Universal Sampling Accessory.

    NASA Astrophysics Data System (ADS)

    Bergin, F. J.; Gilchrist, C. A.; Jones, I.

    1989-12-01

    In recent years the improvement in Fourier transform infrared instrumentation has led to a considerable growth in the use of infrared microscopy as an analytical tool. Many of these applications have concentrated on the spatial resolving power of the microscope for the analysis of small samples or localised contamination within a material. Recently we have been looking at some broader applications of the microscope, in particular, with respect to the non-destructive analysis of bulk polymeric materials and to its use for reflection/absorption measurements of monomolecular films on aqueous substrates. When radiation impinges on a surface the reflected light is generally considered to consist of two components. The first is termed diffuse reflectance and the second Fresnel or specular reflectance. In the case of diffuse reflectance the reflectivity is given by f(R∞) = (1-R∞)2/R∞=k/s, where R∞ is the reflectance from an infinitely thick layer and k and s are related to the absorption and scattering within the sample. Here the term k, related to the absorption, contains molecular information about the material in question. When specular reflectance dominates, the recorded spectrum bears no resemblance to an absorption spectrum but has the appearance of a first derivative spectrum. The reflectivity at normal incidence is given by R = (m-1)2/(m+1)2, where m is the complex refractive, index m = n - ik, and where n is the real component, k the imaginary component or the extinction coefficient and i is √-1 Hence the recorded reflectivity spectrum contains molecular information about the material under investigation. This molecular information can be extracted using the Kramers-Kronig transformation. The experimental system used for this study consisted of a Perkin-Elmer model 1760-X Fourier transform infrared spectrometer. A Spectra-Tech IR Plan microscope, equipped with a narrow band MCT detector and a x15 objective, was fitted to the external port. Data storage

  19. 21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction.... Assisted reproduction microscopes and microscope accessories (excluding microscope stage warmers, which are classified under assisted reproduction accessories) are optical instruments used to enlarge images of...

  20. 21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction.... Assisted reproduction microscopes and microscope accessories (excluding microscope stage warmers, which are classified under assisted reproduction accessories) are optical instruments used to enlarge images of...

  1. 21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction.... Assisted reproduction microscopes and microscope accessories (excluding microscope stage warmers, which are classified under assisted reproduction accessories) are optical instruments used to enlarge images of...

  2. 21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction.... Assisted reproduction microscopes and microscope accessories (excluding microscope stage warmers, which are classified under assisted reproduction accessories) are optical instruments used to enlarge images of...

  3. 21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction.... Assisted reproduction microscopes and microscope accessories (excluding microscope stage warmers, which are classified under assisted reproduction accessories) are optical instruments used to enlarge images of...

  4. Reflective Packaging

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The aluminized polymer film used in spacecraft as a radiation barrier to protect both astronauts and delicate instruments has led to a number of spinoff applications. Among them are aluminized shipping bags, food cart covers and medical bags. Radiant Technologies purchases component materials and assembles a barrier made of layers of aluminized foil. The packaging reflects outside heat away from the product inside the container. The company is developing new aluminized lines, express mailers, large shipping bags, gel packs and insulated panels for the building industry.

  5. Biology Reflective Assessment Curriculum

    NASA Astrophysics Data System (ADS)

    Bayley, Cheryl Ann

    Often students and educators view assessments as an obligation and finality for a unit. In the current climate of high-stakes testing and accountability, the balance of time, resources and emphasis on students' scores related to assessment have been slanted considerably toward the summative side. This tension between assessment for accountability and assessment to inform teaching strains instruction and educators' ability to use that information to design learning opportunities that help students develop deeper conceptual understanding. A substantive body of research indicates that formative and reflective assessment can significantly improve student learning. Biology Reflective Assessment Curriculum (BRAC) examines support provided for high school science students through assessment practices. This investigation incorporates the usage of reflective assessments as a guiding practice for differentiated instruction and student choice. Reflective assessment is a metacognitive strategy that promotes self-monitoring and evaluation. The goals of the curriculum are to promote self-efficacy and conceptual understanding in students learning biology through developing their metacognitive awareness. BRAC was implemented in a high school biology classroom. Data from assessments, metacognitive surveys, self-efficacy surveys, reflective journals, student work, a culminating task and field notes were used to evaluate the effectiveness of the curriculum. The results suggest that students who develop their metacognitive skills developed a deeper conceptual understanding and improved feelings of self-efficacy when they were engaged in a reflective assessment unit embedded with student choice. BRAC is a tool for teachers to use assessments to assist students in becoming metacognitive and to guide student choice in learning opportunities.

  6. Pathology and differential diagnosis of chronic, noninfectious gastritis.

    PubMed

    Polydorides, Alexandros D

    2014-03-01

    The histologic finding of chronic inflammation in an endoscopic mucosal biopsy of the stomach (chronic gastritis) is very common and usually reflects the presence of Helicobacter pylori infection. However, infectious organisms are not always present in biopsy material, and some cases of chronic gastritis do not result from H. pylori infection. Thus, the differential diagnosis of this finding is an important one for pathologists to keep in mind. This review presents the three most common and clinically significant causes of chronic, noninfectious gastritis, namely, autoimmune atrophic gastritis, lymphocytic gastritis, and gastric involvement in the setting of inflammatory bowel disease, especially Crohn disease. For each entity, a brief discussion of its etiology and pathogenesis, a review of the clinical and endoscopic features, and a description of the microscopic findings are presented in the context of the differential diagnosis of chronic gastritis with emphasis on helpful histopathologic hints and long-term sequelae.

  7. An auto-focusing system for white light microscopic measurement

    NASA Astrophysics Data System (ADS)

    Chang, Ming; Deka, Juti Rani; Chen, Pei Jung; Chen, Yu Kuan; Cui, Changcai

    2008-12-01

    With the rapid development of semiconductor technology the demand for high resolution measuring system is evolving at an ever-increasing pace. Microscope was initially used to detect the defect by connecting charge couple device (CCD) as an auxiliary device. In general, for microscopic measurement human eyes are used to focus on the sample. The adjustment depends on the operator's astute measurement ability, which affected the repeatability and accuracy of the readings. There is a need of high-speed microscope auto focusing system for industrial applications. The present investigation describes about the development of an autofocus system to carry out microscopic measurement more precisely and accurately with less time. The measurement system consists of a light source, two beam splitters, a movable sample stage and a Mirau's interferometer, a photo-detector and 8051 microcontroller (MCU89C51). The light reflected from the sample surface interferes with the light reflected from the reference and produce an interference pattern, which is imaged onto a CCD array. In the setup developed for the autofocus one extra beam splitter is placed in the path of interfered beam to the CCD. The beam splitter is placed at equal distances from the CCD and the photodetector. The focus position is determined from the voltage developed in the photo-detector due to the movement of sample stage of the microscope. The maximum voltage that obtained at the focus position is confirmed with the CCD image. Microcontroller is used to stop the controller at the focus position immediately once the sample stage reaches it. Software is developed to locate the maximum intensity position. The design may autofocus the interferometer within 4mm distance in 1 second. The auto-focusing not only provides enhanced repeatability and accuracy of the results at a faster rate but also minimizes operator involvement.

  8. New Microscope Scans Breast Tumors During Surgery

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_166925.html New Microscope Scans Breast Tumors During Surgery The instrument ... 2017 WEDNESDAY, June 28, 2017 (HealthDay News) -- A new microscope could help surgeons remove breast tumors completely, ...

  9. Mars Life? - Microscopic Egg-shaped Structures

    NASA Image and Video Library

    1996-08-09

    This electron microscope image shows egg-shaped structures, some of which may be possible microscopic fossils of Martian origin as discussed by NASA research published in the Aug. 16, 1996. http://photojournal.jpl.nasa.gov/catalog/PIA00286

  10. Reflection contrast microscopy within chrome-alum haematoxylin stained thick tissue-sections.

    PubMed

    Filler, T J; Rickert, C H; Fassnacht, U K; Pera, F

    1994-06-01

    This paper introduces two innovations in reflection contrast microscopy (RCM): (1) an extended application for qualitative light microscopic investigations; and (2) a novel method for quantification in cytochemistry. (1) We found out that RCM cannot only be used for surface characterizations and in thin sections but also within thick tissue-sections. The use of the RCM technique is demonstrated on slides of the supraoptic nucleus (SON) of the rat stained with chrome-alum haematoxylin: Among all the stained structures only neurosecretory granules are found to cause reflections. The visualization of the neurosecretion and its distribution is more distinct and of sharper contrast than in bright field microscopy. (2) The improved differentiation allows the quantification of neurosecretion in tissue-sections by combining RCM with grey-scale image analysis.

  11. A Student-Built Scanning Tunneling Microscope

    ERIC Educational Resources Information Center

    Ekkens, Tom

    2015-01-01

    Many introductory and nanotechnology textbooks discuss the operation of various microscopes including atomic force (AFM), scanning tunneling (STM), and scanning electron microscopes (SEM). In a nanotechnology laboratory class, students frequently utilize microscopes to obtain data without a thought about the detailed operation of the tool itself.…

  12. A Student-Built Scanning Tunneling Microscope

    ERIC Educational Resources Information Center

    Ekkens, Tom

    2015-01-01

    Many introductory and nanotechnology textbooks discuss the operation of various microscopes including atomic force (AFM), scanning tunneling (STM), and scanning electron microscopes (SEM). In a nanotechnology laboratory class, students frequently utilize microscopes to obtain data without a thought about the detailed operation of the tool itself.…

  13. Microscopic Analysis of Activated Sludge. Training Manual.

    ERIC Educational Resources Information Center

    Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

    This training manual presents material on the use of a compound microscope to analyze microscope communities, present in wastewater treatment processes, for operational control. Course topics include: sampling techniques, sample handling, laboratory analysis, identification of organisms, data interpretation, and use of the compound microscope.…

  14. Discovery Through the Computational Microscope

    PubMed Central

    Lee, Eric H.; Hsin, Jen; Sotomayor, Marcos; Comellas, Gemma; Schulten, Klaus

    2010-01-01

    Summary All-atom molecular dynamics simulations have become increasingly popular as a tool to investigate protein function and dynamics. However, researchers are concerned about the short time scales covered by simulations, the apparent impossibility to model large and integral biomolecular systems, and the actual predictive power of the molecular dynamics methodology. Here we review simulations that were in the past both hotly disputed and considered key successes, namely of proteins with mainly mechanical functions (titin, fibrinogen, ankyrin, and cadherin). The simulation work covered shows how state-of-the-art modeling alleviates some of the prior concerns, and how unrefuted discoveries are made through the “computational microscope". PMID:19836330

  15. Stimulated Parametric Emission Microscope Systems

    NASA Astrophysics Data System (ADS)

    Itoh, Kazuyoshi; Isobe, Keisuke

    2006-10-01

    We present a novel microscopy technique based on the fourwave mixing (FWM) process that is enhanced by two-photon electronic resonance induced by a pump pulse along with stimulated emission induced by a dump pulse. A Ti:sapphire laser and an optical parametric oscillator are used as light sources for the pump and dump pulses, respectively. We demonstrate that our FWM technique can be used to obtain two-dimensional microscopic images of an unstained leaf of Camellia sinensis and an unlabeled tobacco BY2 Cell.

  16. Stimulated Brillouin Scattering Microscopic Imaging

    PubMed Central

    Ballmann, Charles W.; Thompson, Jonathan V.; Traverso, Andrew J.; Meng, Zhaokai; Scully, Marlan O.; Yakovlev, Vladislav V.

    2015-01-01

    Two-dimensional stimulated Brillouin scattering microscopy is demonstrated for the first time using low power continuous-wave lasers tunable around 780 nm. Spontaneous Brillouin spectroscopy has much potential for probing viscoelastic properties remotely and non-invasively on a microscopic scale. Nonlinear Brillouin scattering spectroscopy and microscopy may provide a way to tremendously accelerate the data aquisition and improve spatial resolution. This general imaging setup can be easily adapted for specific applications in biology and material science. The low power and optical wavelengths in the water transparency window used in this setup provide a powerful bioimaging technique for probing the mechanical properties of hard and soft tissue. PMID:26691398

  17. Microscopic tubes in igneous rocks

    NASA Technical Reports Server (NTRS)

    Richter, D.; Simmons, G.

    1977-01-01

    Microscopic tubes have been observed in several igneous rocks and may be quite common. They occur in single crystals and have either elliptical or circular cross-sections 1 to 5 microns in diameter and are ten to hundreds of microns long. Microtubes may be hollow or partially or completely filled with another phase, but are distinct from acicular crystals of accessory minerals such as rutile. Microtubes can form by at least three processes: (1) the partial annealing of microcracks, (2) the natural etching of dislocations, or (3) the primary inclusion of fluid material during crystal growth.

  18. Ballistic-Electron-Emission Microscope

    NASA Technical Reports Server (NTRS)

    Kaiser, William J.; Bell, L. Douglas

    1990-01-01

    Ballistic-electron-emission microscope (BEEM) employs scanning tunneling-microscopy (STM) methods for nondestructive, direct electrical investigation of buried interfaces, such as interface between semiconductor and thin metal film. In BEEM, there are at least three electrodes: emitting tip, biasing electrode, and collecting electrode, receiving current crossing interface under investigation. Signal-processing device amplifies electrode signals and converts them into form usable by computer. Produces spatial images of surface by scanning tip; in addition, provides high-resolution images of buried interface under investigation. Spectroscopic information extracted by measuring collecting-electrode current as function of one of interelectrode voltages.

  19. Solid-state optical microscope

    DOEpatents

    Young, I.T.

    1981-01-07

    A solid state optical microscope is described wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. Means for scanning in one of two orthogonal directions are provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

  20. High-speed atomic force microscope combined with single-molecule fluorescence microscope

    NASA Astrophysics Data System (ADS)

    Fukuda, Shingo; Uchihashi, Takayuki; Iino, Ryota; Okazaki, Yasutaka; Yoshida, Masato; Igarashi, Kiyohiko; Ando, Toshio

    2013-07-01

    High-speed atomic force microscopy (HS-AFM) and total internal reflection fluorescence microscopy (TIRFM) have mutually complementary capabilities. Here, we report techniques to combine these microscopy systems so that both microscopy capabilities can be simultaneously used in the full extent. To combine the two systems, we have developed a tip-scan type HS-AFM instrument equipped with a device by which the laser beam from the optical lever detector can track the cantilever motion in the X- and Y-directions. This stand-alone HS-AFM system is mounted on an inverted optical microscope stage with a wide-area scanner. The capability of this combined system is demonstrated by simultaneous HS-AFM/TIRFM imaging of chitinase A moving on a chitin crystalline fiber and myosin V walking on an actin filament.

  1. High-speed atomic force microscope combined with single-molecule fluorescence microscope.

    PubMed

    Fukuda, Shingo; Uchihashi, Takayuki; Iino, Ryota; Okazaki, Yasutaka; Yoshida, Masato; Igarashi, Kiyohiko; Ando, Toshio

    2013-07-01

    High-speed atomic force microscopy (HS-AFM) and total internal reflection fluorescence microscopy (TIRFM) have mutually complementary capabilities. Here, we report techniques to combine these microscopy systems so that both microscopy capabilities can be simultaneously used in the full extent. To combine the two systems, we have developed a tip-scan type HS-AFM instrument equipped with a device by which the laser beam from the optical lever detector can track the cantilever motion in the X- and Y-directions. This stand-alone HS-AFM system is mounted on an inverted optical microscope stage with a wide-area scanner. The capability of this combined system is demonstrated by simultaneous HS-AFM∕TIRFM imaging of chitinase A moving on a chitin crystalline fiber and myosin V walking on an actin filament.

  2. Reflected Glory

    NASA Astrophysics Data System (ADS)

    2011-02-01

    The nebula Messier 78 takes centre stage in this image taken with the Wide Field Imager on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile, while the stars powering the bright display take a backseat. The brilliant starlight ricochets off dust particles in the nebula, illuminating it with scattered blue light. Igor Chekalin was the overall winner of ESO's Hidden Treasures 2010 astrophotography competition with his image of this stunning object. Messier 78 is a fine example of a reflection nebula. The ultraviolet radiation from the stars that illuminate it is not intense enough to ionise the gas to make it glow - its dust particles simply reflect the starlight that falls on them. Despite this, Messier 78 can easily be observed with a small telescope, being one of the brightest reflection nebulae in the sky. It lies about 1350 light-years away in the constellation of Orion (The Hunter) and can be found northeast of the easternmost star of Orion's belt. This new image of Messier 78 from the MPG/ESO 2.2-metre telescope at the La Silla Observatory is based on data selected by Igor Chekalin in his winning entry to the Hidden Treasures competition [1]. The pale blue tint seen in the nebula in this picture is an accurate representation of its dominant colour. Blue hues are commonly seen in reflection nebulae because of the way the starlight is scattered by the tiny dust particles that they contain: the shorter wavelength of blue light is scattered more efficiently than the longer wavelength red light. This image contains many other striking features apart from the glowing nebula. A thick band of obscuring dust stretches across the image from the upper left to the lower right, blocking the light from background stars. In the bottom right corner, many curious pink structures are also visible, which are created by jets of material being ejected from stars that have recently formed and are still buried deep in dust clouds. Two bright stars, HD 38563A and

  3. Martian Magnets Under the Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit acquired this microscopic imager view of its capture magnet on sol 92 (April 6, 2004). Both Spirit and the Mars Exploration Rover Opportunity are equipped with a number of magnets. The capture magnet, as seen here, has a stronger charge than its sidekick, the filter magnet. The lower-powered filter magnet captures only the most magnetic airborne dust with the strongest charges, while the capture magnet picks up all magnetic airborne dust.

    The magnets' primary purpose is to collect the martian magnetic dust so that scientists can analyze it with the rovers' Moessbauer spectrometers. While there is plenty of dust on the surface of Mars, it is difficult to confirm where it came from, and when it was last airborne. Because scientists are interested in learning about the properties of the dust in the atmosphere, they devised this dust-collection experiment.

    The capture magnet is about 4.5 centimeters (1.8 inches) in diameter and is constructed with a central cylinder and three rings, each with alternating orientations of magnetization. Scientists have been monitoring the continual accumulation of dust since the beginning of the mission with panoramic camera and microscopic imager images. They had to wait until enough dust accumulated before they could get a Moessbauer spectrometer analysis. The results of that analysis, performed on sol 92, have not been sent back to Earth yet.

  4. Microscopic colitis: A literature review.

    PubMed

    Clara, Ana Paula Hamer Sousa; Magnago, Flávia Drago; Ferreira, Juliana Neves; Grillo, Thais Gagno

    2016-12-01

    Microscopic colitis (MC) refers to chronic inflammation of the colon which is characterized by histologic changes at the level of a radiologically and endoscopically normal mucosa. It is a common cause of chronic non-bloody diarrhea that occurs primarily in older individuals; however, there are few studies in the literature with strong scientific evidence compared to other inflammatory bowel diseases (IBD), which limits the knowledge of physicians and pathologists. This article aims to review the information on MC, describing diagnostic methods and drugs available for treatment. We conducted a search of the Pubmed database and CAPES Portal using the keywords "microscopic colitis", "collagenous colitis", "lymphocytic colitis", and "review" for selection of articles published between 1996 and 2015 related to the topic. Based on the studies discussed in this review, we conclude that MC is a relatively new gastrointestinal disorder, most studies are incipient particularly with respect to pathophysiology and immunology, and budesonide is the best documented short-term treatment. However, further studies are needed to elucidate the best strategy for treatment in the long term.

  5. Sensing mode atomic force microscope

    DOEpatents

    Hough, Paul V. C.; Wang, Chengpu

    2006-08-22

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  6. Sensing mode atomic force microscope

    DOEpatents

    Hough, Paul V.; Wang, Chengpu

    2004-11-16

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  7. Martian Magnets Under the Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit acquired this microscopic imager view of its capture magnet on sol 92 (April 6, 2004). Both Spirit and the Mars Exploration Rover Opportunity are equipped with a number of magnets. The capture magnet, as seen here, has a stronger charge than its sidekick, the filter magnet. The lower-powered filter magnet captures only the most magnetic airborne dust with the strongest charges, while the capture magnet picks up all magnetic airborne dust.

    The magnets' primary purpose is to collect the martian magnetic dust so that scientists can analyze it with the rovers' Moessbauer spectrometers. While there is plenty of dust on the surface of Mars, it is difficult to confirm where it came from, and when it was last airborne. Because scientists are interested in learning about the properties of the dust in the atmosphere, they devised this dust-collection experiment.

    The capture magnet is about 4.5 centimeters (1.8 inches) in diameter and is constructed with a central cylinder and three rings, each with alternating orientations of magnetization. Scientists have been monitoring the continual accumulation of dust since the beginning of the mission with panoramic camera and microscopic imager images. They had to wait until enough dust accumulated before they could get a Moessbauer spectrometer analysis. The results of that analysis, performed on sol 92, have not been sent back to Earth yet.

  8. Inspection with Robotic Microscopic Imaging

    NASA Technical Reports Server (NTRS)

    Pedersen, Liam; Deans, Matthew; Kunz, Clay; Sargent, Randy; Chen, Alan; Mungas, Greg

    2005-01-01

    Future Mars rover missions will require more advanced onboard autonomy for increased scientific productivity and reduced mission operations cost. One such form of autonomy can be achieved by targeting precise science measurements to be made in a single command uplink cycle. In this paper we present an overview of our solution to the subproblems of navigating a rover into place for microscopic imaging, mapping an instrument target point selected by an operator using far away science camera images to close up hazard camera images, verifying the safety of placing a contact instrument on a sample or finding nearby safe points, and analyzing the data that comes back from the rover. The system developed includes portions used in the Multiple Target Single Cycle Instrument Placement demonstration at NASA Ames in October 2004, and portions of the MI Toolkit delivered to the Athena Microscopic Imager Instrument Team for the MER mission still operating on Mars today. Some of the component technologies are also under consideration for MSL mission infusion.

  9. Sensing mode atomic force microscope

    DOEpatents

    Hough, Paul V. C.; Wang, Chengpu

    2003-01-01

    An atomic force microscope utilizes a pulse release system and improved method of operation to minimize contact forces between a probe tip affixed to a flexible cantilever and a specimen being measured. The pulse release system includes a magnetic particle affixed proximate the probe tip and an electromagnetic coil. When energized, the electromagnetic coil generates a magnetic field which applies a driving force on the magnetic particle sufficient to overcome adhesive forces exhibited between the probe tip and specimen. The atomic force microscope includes two independently displaceable piezo elements operable along a Z-axis. A controller drives the first Z-axis piezo element to provide a controlled approach between the probe tip and specimen up to a point of contact between the probe tip and specimen. The controller then drives the first Z-axis piezo element to withdraw the cantilever from the specimen. The controller also activates the pulse release system which drives the probe tip away from the specimen during withdrawal. Following withdrawal, the controller adjusts the height of the second Z-axis piezo element to maintain a substantially constant approach distance between successive samples.

  10. Design of a normal incidence multilayer imaging X-ray microscope

    NASA Technical Reports Server (NTRS)

    Shealy, David L.; Gabardi, David R.; Hoover, Richard B.; Walker, Arthur B. C., Jr.; Lindblom, Joakim F.

    1989-01-01

    Normal incidence multilayer Cassegrain X-ray telescopes were flown on the Stanford/MSFC Rocket X-ray Spectroheliograph. These instruments produced high spatial resolution images of the sun and conclusively demonstrated that doubly reflecting multilayer X-ray optical systems are feasible. The images indicated that aplanatic imaging soft X-ray/EUV microscopes should be achievable using multilayer optics technology. A doubly reflecting normal incidence multilayer imaging X-ray microscope based on the Schwarzschild configuration has been designed. The design of the microscope and the results of the optical system ray trace analysis are discussed. High resolution aplanatic imaging X-ray microscopes using normal incidence multilayer X-ray mirrors should have many important applications in advanced X-ray astronomical instrumentation, X-ray lithography, biological, biomedical, metallurgical, and laser fusion research.

  11. Optical inversions based on polarization parameters indirect microscopic imaging

    NASA Astrophysics Data System (ADS)

    Liu, Guoyan; Gao, Kun; Liu, Xuefeng; Huang, Zicheng; Ni, Guoqiang

    2016-10-01

    The resolution of conventional optical microscope is intrinsically limited by the optical diffraction, therefore it cannot be used in the measurement of sub-100nm shape and structural detection. Non-optical imaging techniques are not limited by the optical diffraction. For example, scanning tunneling microscopy (STM) and atomic force microscopy (AFM), but both of them have the weakness of narrow view field, low efficiency, and excessive cost. To detect nanoscale material, a new microscopic imaging technique is introduced in this paper, i.e. the polarization parameter indirect microscopic imaging technique. A conventional reflection microscopic system is used as the basic optical system, with polarization-modulation mechanics being inserted into it. The near-field structural characteristics can be delivered by optical wave and material coupling. According to coupling and conduction physics, changes of the optical wave parameters can be calculated, and then curves of the image intensity can be obtained. By analyzing the near-field polarization parameters in nanoscale, indirect polarization parameter imaging can be established.

  12. Robotic autopositioning of the operating microscope.

    PubMed

    Oppenlander, Mark E; Chowdhry, Shakeel A; Merkl, Brandon; Hattendorf, Guido M; Nakaji, Peter; Spetzler, Robert F

    2014-06-01

    Use of the operating microscope has become pervasive since its introduction to the neurosurgical world. Neuronavigation fused with the operating microscope has allowed accurate correlation of the focal point of the microscope and its location on the downloaded imaging study. However, the robotic ability of the Pentero microscope has not been utilized to orient the angle of the microscope or to change its focal length to hone in on a predefined target. To report a novel technology that allows automatic positioning of the operating microscope onto a set target and utilization of a planned trajectory, either determined with the StealthStation S7 by using preoperative imaging or intraoperatively with the microscope. By utilizing the current motorized capabilities of the Zeiss OPMI Pentero microscope, a robotic autopositioning feature was developed in collaboration with Surgical Technologies, Medtronic, Inc. (StealthStation S7). The system is currently being tested at the Barrow Neurological Institute. Three options were developed for automatically positioning the microscope: AutoLock Current Point, Align Parallel to Plan, and Point to Plan Target. These options allow the microscope to pivot around the lesion, hover in a set plane parallel to the determined trajectory, or rotate and point to a set target point, respectively. Integration of automatic microscope positioning into the operative workflow has potential to increase operative efficacy and safety. This technology is best suited for precise trajectories and entry points into deep-seated lesions.

  13. Cancer systems biology and modeling: microscopic scale and multiscale approaches.

    PubMed

    Masoudi-Nejad, Ali; Bidkhori, Gholamreza; Hosseini Ashtiani, Saman; Najafi, Ali; Bozorgmehr, Joseph H; Wang, Edwin

    2015-02-01

    Cancer has become known as a complex and systematic disease on macroscopic, mesoscopic and microscopic scales. Systems biology employs state-of-the-art computational theories and high-throughput experimental data to model and simulate complex biological procedures such as cancer, which involves genetic and epigenetic, in addition to intracellular and extracellular complex interaction networks. In this paper, different systems biology modeling techniques such as systems of differential equations, stochastic methods, Boolean networks, Petri nets, cellular automata methods and agent-based systems are concisely discussed. We have compared the mentioned formalisms and tried to address the span of applicability they can bear on emerging cancer modeling and simulation approaches. Different scales of cancer modeling, namely, microscopic, mesoscopic and macroscopic scales are explained followed by an illustration of angiogenesis in microscopic scale of the cancer modeling. Then, the modeling of cancer cell proliferation and survival are examined on a microscopic scale and the modeling of multiscale tumor growth is explained along with its advantages. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Fluorescein sodium fluorescence microscope-integrated lymphangiography for lymphatic supermicrosurgery.

    PubMed

    Ayestaray, Benoit; Bekara, Farid

    2015-07-01

    Microscope-integrated lymphangiography is a useful method in the field of lymphatic supermicrosurgery. Fluorescence based on indocyanine green (ICG) is the most commonly used. Fluorescein sodium is a fluorescent tracer used for retinal and neurosurgical angiography but not yet for lymphatic supermicrosurgery. In this report, we present a case in which the fluorescein sodium fluorescence microscope-integrated lymphangiography was used for assessment of lymphatic drainage pathway and patency in a patient treated for secondary lymphedema by lymphaticovenular anastomoses. Fluorescein sodium fluorescence microscope-integrated lymphangiography was evaluated in a 67-year-old female presented for a Campisi clinical stage IV lymphedema of the upper limb. Transcutaneous guidance and vascular fluorescence were assessed. A comparison with ICG fluorescence was made intraoperatively. Two lymphaticovenular anastomoses were performed and their patency were checked by lymphangiography. Transcutaneous signal was found higher with fluorescein sodium fluorescence. Intraluminal visualization was possible with fluorescein sodium coloration during lymphaticovenular anastomoses. No adverse reaction occurred. The circumferential differential reduction rate of affected limb was 8.1% 3 months after lymphaticovenular anastomoses. The use of fluorescence microscope-integrated lymphangiography with fluorescein sodium may be superior to ICG fluorescence in assistance of lymphaticovenular anastomoses.

  15. Parameter estimation method for blurred cell images from fluorescence microscope

    NASA Astrophysics Data System (ADS)

    He, Fuyun; Zhang, Zhisheng; Luo, Xiaoshu; Zhao, Shulin

    2016-10-01

    Microscopic cell image analysis is indispensable to cell biology. Images of cells can easily degrade due to optical diffraction or focus shift, as this results in low signal-to-noise ratio (SNR) and poor image quality, hence affecting the accuracy of cell analysis and identification. For a quantitative analysis of cell images, restoring blurred images to improve the SNR is the first step. A parameter estimation method for defocused microscopic cell images based on the power law properties of the power spectrum of cell images is proposed. The circular radon transform (CRT) is used to identify the zero-mode of the power spectrum. The parameter of the CRT curve is initially estimated by an improved differential evolution algorithm. Following this, the parameters are optimized through the gradient descent method. Using synthetic experiments, it was confirmed that the proposed method effectively increased the peak SNR (PSNR) of the recovered images with high accuracy. Furthermore, experimental results involving actual microscopic cell images verified that the superiority of the proposed parameter estimation method for blurred microscopic cell images other method in terms of qualitative visual sense as well as quantitative gradient and PSNR.

  16. [Development of slit-lamp microscope and its applications in optics].

    PubMed

    Qi, Haohui

    2013-11-01

    This paper mainly introduces the origin and development of the slit-lamp microscope, the basic structure, working principle and test methods, focuses on diffuse illumination, direct focal illumination, indirect illumination, retro illumination, zone of specular reflection and slit-lamp filter used in the optical inspection, to provide the reference for clinical general optometry practitioners and using slit-lamp microscope widely and standardized.

  17. High-resolution fiber optic confocal microscope

    NASA Astrophysics Data System (ADS)

    Ilev, Ilko K.; Waynant, Ronald W.

    2001-04-01

    A novel design of a simple reflection confocal microscope with a multimode graded-index fiber output as an effective way for improving the dynamic range of the resolving power and achieving a submicron spatial resolution is presented. The basic idea for obtaining high spatial resolution involves the following advanced scheme properties. (1) It is an apertureless confocal arrangement in which the input laser emission with its maximum power is launched directly to the test object. (2) It uses a high-numerical-aperture focusing objective (NA>0.8) that provides high depth and spatial discriminations and thus, high axial and lateral resolutions are obtained. (3) It uses a graded-index multimode fiber (50-μm-core diameter) for signal detection rather than a conventional pinhole or single-mode fiber. The graded-index fiber ensures efficient launching and maintenance of high laser powers, and high sensitivity of signal detection. Moreover, according to the equivalent-Gaussian-mode model, the intensity mode distribution into the graded-index fiber can be presented as an equivalent Gaussian mode distribution. As a result, a significant reduction of the mode noise of the intensity distribution and of signal fluctuations is obtained. Thus, a regime of high-output power is achieved that provides high resolving power and a submicron axial resolution of 0.4 μm.

  18. Improved Spatial Resolution for Reflection Mode Infrared Microscopy

    SciTech Connect

    Bechtel, Hans A.; Martin, Michael C.; May, T.E.; Lerch, Philippe

    2009-10-09

    Standard commercial infrared microscopes operating in reflection mode use a mirror to direct the reflected light from the sample to the detector. This mirror blocks about half of the incident light, however, and thus degrades the spatial resolution by reducing the umerical aperture of the objective. Here, we replace the mirror with a 50% beamsplitter to allow full illumination of the objective and retain a way to direct the reflected light to the detector. The improved spatial resolution is demonstrated using two different microscopes apable of diffraction-limited resolution: the first microscope is coupled to a synchrotron source and utilizes a single point detector, whereas the second microscope has a standard blackbody source and uses a focal planetarray (FPA) detector.

  19. Multimodal optical workstation for simultaneous linear, nonlinear microscopy and nanomanipulation: upgrading a commercial confocal inverted microscope.

    PubMed

    Mathew, Manoj; Santos, Susana I C O; Zalvidea, Dobryna; Loza-Alvarez, Pablo

    2009-07-01

    In this work we propose and build a multimodal optical workstation that extends a commercially available confocal microscope (Nikon Confocal C1-Si) to include nonlinear/multiphoton microscopy and optical manipulation/stimulation tools such as nanosurgery. The setup allows both subsystems (confocal and nonlinear) to work independently and simultaneously. The workstation enables, for instance, nanosurgery along with simultaneous confocal and brightfield imaging. The nonlinear microscopy capabilities are added around the commercial confocal microscope by exploiting all the flexibility offered by this microscope and without need for any mechanical or electronic modification of the confocal microscope systems. As an example, the standard differential interference contrast condenser and diascopic detector in the confocal microscope are readily used as a forward detection mount for second harmonic generation imaging. The various capabilities of this workstation, as applied directly to biology, are demonstrated using the model organism Caenorhabditis elegans.

  20. Nuclear data evaluation of long-lived fission products: Microscopic vs. phenomenological optical potentials

    NASA Astrophysics Data System (ADS)

    Minato, Futoshi; Iwamoto, Osamu; Minomo, Kosho; Ogata, Kazuyuki; Iwamoto, Nobuyuki; Kunieda, Satoshi; Furutachi, Naoya

    2017-09-01

    Neutron-nucleus cross sections calculated by macroscopic potentials are compared with a microscopic one to study the performance for long-lived fission products. The macroscopic potentials show a good agreement with the microscopic one at higher energies, where neutron experimental data are scarce. Besides it, analyses of differential elastic cross sections at low energies also suggest that the macroscopic potentials are still effective and applicable enough for the long-lived fission products.

  1. On-axis microscopes for the inelastic x-ray scattering beamline at NSLS-II

    SciTech Connect

    Gofron, K. J. Cai, Y. Q.; Coburn, D. S.; Antonelli, S.; Suvorov, A.; Flores, J.

    2016-07-27

    A novel on-axis X-ray microscope with 3 µm resolution, 3x magnification, and a working distance of 600 mm for in-situ sample alignment and X-ray beam visualization for the Inelastic X-ray Scattering (IXS) beamline at NSLS-II is presented. The microscope uses reflective optics, which minimizes dispersion, and allows imaging from Ultraviolet (UV) to Infrared (IR) with specifically chosen objective components (coatings, etc.). Additionally, a portable high resolution X-ray microscope for KB mirror alignment and X-ray beam characterization was developed.

  2. Wakata performs microscopic analysis of the NanoRacks Module-38 Petri Dishes

    NASA Image and Video Library

    2014-01-13

    ISS038-E-029082 (12 Jan. 2014) --- Japan Aerospace Exploration Agency astronaut Koichi Wakata, Expedition 38 flight engineer, performs microscopic analysis of the NanoRacks Module-38 Petri Dishes, using Celestron Reflective Microscope, in the Kibo laboratory of the International Space Station. These Module-38 experiments are designed by students as part of a competition sponsored by the International Space School Educational Trust (ISSET). This experiment examines three-dimensional growth of slime mold in petri dishes utilizing the NanoRacks Microscopes Facility.

  3. Scanning Quantum Cryogenic Atom Microscope

    NASA Astrophysics Data System (ADS)

    Yang, Fan; Kollár, Alicia J.; Taylor, Stephen F.; Turner, Richard W.; Lev, Benjamin L.

    2017-03-01

    Microscopic imaging of local magnetic fields provides a window into the organizing principles of complex and technologically relevant condensed-matter materials. However, a wide variety of intriguing strongly correlated and topologically nontrivial materials exhibit poorly understood phenomena outside the detection capability of state-of-the-art high-sensitivity high-resolution scanning probe magnetometers. We introduce a quantum-noise-limited scanning probe magnetometer that can operate from room-to-cryogenic temperatures with unprecedented dc-field sensitivity and micron-scale resolution. The Scanning Quantum Cryogenic Atom Microscope (SQCRAMscope) employs a magnetically levitated atomic Bose-Einstein condensate (BEC), thereby providing immunity to conductive and blackbody radiative heating. The SQCRAMscope has a field sensitivity of 1.4 nT per resolution-limited point (approximately 2 μ m ) or 6 nT /√{Hz } per point at its duty cycle. Compared to point-by-point sensors, the long length of the BEC provides a naturally parallel measurement, allowing one to measure nearly 100 points with an effective field sensitivity of 600 pT /√{Hz } for each point during the same time as a point-by-point scanner measures these points sequentially. Moreover, it has a noise floor of 300 pT and provides nearly 2 orders of magnitude improvement in magnetic flux sensitivity (down to 10-6 Φ0/√{Hz } ) over previous atomic probe magnetometers capable of scanning near samples. These capabilities are carefully benchmarked by imaging magnetic fields arising from microfabricated wire patterns in a system where samples may be scanned, cryogenically cooled, and easily exchanged. We anticipate the SQCRAMscope will provide charge-transport images at temperatures from room temperature to 4 K in unconventional superconductors and topologically nontrivial materials.

  4. The Use of Microscopes and Telescopes in IR Imaging

    SciTech Connect

    Dinwiddie, Ralph Barton

    2011-01-01

    A wide selection of lenses is very useful to the thermographer working in a research environment, where applications can vary from week to week. Both wide angle and telephoto infrared lenses are widely used alternatives to the standard lenses typically supplied by IR camera manufacturers. However, in some extreme applications the need arises for additional image magnification. In these cases, the thermographer must rely on an IR microscope for close-up work with a field of view on the order of 1.3 to 15.8 mm, or a telescope for working at a distance on the order of meters or kilometers. The advantages of using an IR microscope and reflecting telescope will be discussed, as well as the challenges and characteristics of using these instruments.

  5. X-ray microscope assemblies. Final report and metrology report

    SciTech Connect

    Zehnpfennig, T.F.

    1981-04-13

    This is the Final Report and Metrology Report prepared under Lawrence Livermore Laboratory Subcontract 9936205, X-ray Microscope Assemblies. The purpose of this program was to design, fabricate, and perform detailed metrology on an axisymmetric grazing-incidence x-ray microscope (XRMS) to be used as a diagnostic instrument in the Lawrence Livermore Laser Fusion Program. The optical configuration chosen for this device consists of two internally polished surfaces of revolution: an hyperboloid facing the object; and a confocal, co-axial elliposid facing the image. This arrangement is known as the Wolter Type-I configuration. The grazing angle of reflection for both surfaces is approximately 1/sup 0/. The general optical performance goals under this program were to achieve a spatial resolution in the object plane in the soft x-ray region of approximately 1 micron, and to achieve an effective solid collecting angle which is an appreciable fraction of the geometric solid collecting angle.

  6. Automated dimensional analysis using a light-sectioning microscope

    SciTech Connect

    Loomis, J.; Lightman, A.; Poe, A.; Caldwell, R.

    1988-12-31

    A computer vision system has been integrated with a modified light-sectioning microscope for quality control and inspection of a machined part whose critical dimensions are 30 to 300 {mu}m. Height measurements were determined by analysis of the projected light-section line. Transverse measurements were made using the microscope in a traditional configuration with illumination from selected elements of an external LED ring array. The light section irradiance was under computer control to accommodate the spatial variations in surface reflectance whose dynamic range exceeded that of the vision system. Part features are located by the vision system. Edges and line centers are then measured to sub-pixel resolution with a gray-level analysis algorithm. This paper describes the design and operation of this system. Details of the measurement process and analysis algorithms are provided.

  7. Laser confocal microscope with wavelet-profiled point spread function

    NASA Astrophysics Data System (ADS)

    Romero, Mary Jacquiline; Bautista, Godofredo; Daria, Vincent Ricardo; Saloma, Caesar

    2010-04-01

    We report a laser-scanning confocal reflectance microscope with a wavelet-profiled point spread function (PSF) for rapid multi-resolution extraction and analysis of microscopic object features. The PSF is generated via holography by encoding a π-phase shifting disk unto a collimated laser beam via a phase-only spatial light modulator (SLM) that is positioned at the pupil plane of the focusing objective lens. Scaling of the transverse PSF distribution is achieved by selecting a suitable ratio of the π-phase shifting disk radius and the pupil aperture radius. With one and the same objective lens and one SLM to control the phase profile of the pupil function, we produce amplitude PSF distributions that are accurate scaled representations of the circularly-symmetric Mexican hat mother wavelet.

  8. Confocal Microscope Alignment of Nanocrystals for Coherent Diffraction Imaging

    NASA Astrophysics Data System (ADS)

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

    2010-06-01

    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.

  9. In vivo cellular imaging with microscopes enabled by MEMS scanners

    NASA Astrophysics Data System (ADS)

    Ra, Hyejun

    High-resolution optical imaging plays an important role in medical diagnosis and biomedical research. Confocal microscopy is a widely used imaging method for obtaining cellular and sub-cellular images of biological tissue in reflectance and fluorescence modes. Its characteristic optical sectioning capability also enables three-dimensional (3-D) image reconstruction. However, its use has mostly been limited to excised tissues due to the requirement of high numerical aperture (NA) lenses for cellular resolution. Microscope miniaturization can enable in vivo imaging to make possible early cancer diagnosis and biological studies in the innate environment. In this dissertation, microscope miniaturization for in vivo cellular imaging is presented. The dual-axes confocal (DAC) architecture overcomes limitations of the conventional single-axis confocal (SAC) architecture to allow for miniaturization with high resolution. A microelectromechanical systems (MEMS) scanner is the central imaging component that is key in miniaturization of the DAC architecture. The design, fabrication, and characterization of the two-dimensional (2-D) MEMS scanner are presented. The gimbaled MEMS scanner is fabricated on a double silicon-on-insulator (SOI) wafer and is actuated by self-aligned vertical electrostatic combdrives. The imaging performance of the MEMS scanner in a DAC configuration is shown in a breadboard microscope setup, where reflectance and fluorescence imaging is demonstrated. Then, the MEMS scanner is integrated into a miniature DAC microscope. The whole imaging system is integrated into a portable unit for research in small animal models of human biology and disease. In vivo 3-D imaging is demonstrated on mouse skin models showing gene transfer and siRNA silencing. The siRNA silencing process is sequentially imaged in one mouse over time.

  10. Low-price optical microscope for school science education

    NASA Astrophysics Data System (ADS)

    Hoshimiya, Tsutomu; Kumagai, Masaaki

    2007-06-01

    In schools, scientific education with an optical microscope is popularly used. However, scanning apparatus for the microscope is very expensive such that the price is several times higher than the microscope itself. In order to activate children's interest in science, a low-price scanning and imaging function unit compatible to conventional optical microscopes used in schools was designed and manufactured using a personal computer (PC) used in all elementally and middle school education. The designing of imaging apparatus includes two choices: (i) using imaging device (reflection-type), or (ii) using photo-sensor and scanning device (transmission-type). In this paper, the latter method is adopted, considering the educational effect using "Lambert-Beer's law". This apparatus measures optical transmittance of modulated visible light with a photo-detector, and uses audio-input unit of PC as an A/D converter. Scanning unit with a pair of pulse motor drives was also used. Control software was built on Knoppix (an operating system based on freeware Linux), however it is very easy to rewrite to Windows application. By these reasons, this apparatus is low-price (less than microscope price) so that it is one of the best candidates for science education application in schools. As a biological specimen, a wing of spider wasp (Pompilidae) was used. Measured region was 10mm×10mm and the resolution was 100×100 pixels. The photograph of original specimen and the obtained image were shown in Figures (a) and (b), respectively. The obtained image showed a well-resolved detailed structure of the wing. Scanning was done by an external scanning apparatus. However, feeding of scanning pulses through printer port to stepping motor will be available based on the same method.

  11. A Reflective Look at Reflecting Teams

    ERIC Educational Resources Information Center

    Pender, Rebecca L.; Stinchfield, Tracy

    2012-01-01

    This article reviewed existing literature and research on the reflecting team process. There is a dearth of empirical research that explores the reflecting team process and the outcome of counseling that uses reflecting teams. Implications of using reflecting teams for counselors, counselor educators, and clients will be discussed. A call for…

  12. A high-resolution multimode digital microscope system.

    PubMed

    Salmon, Edward D; Shaw, Sidney L; Waters, Jennifer C; Waterman-Storer, Clare M; Maddox, Paul S; Yeh, Elaine; Bloom, Kerry

    2013-01-01

    This chapter describes the development of a high-resolution, multimode digital imaging system based on a wide-field epifluorescent and transmitted light microscope, and a cooled charge-coupled device (CCD) camera. The three main parts of this imaging system are Nikon FXA microscope, Hamamatsu C4880 cooled CCD camera, and MetaMorph digital imaging system. This chapter presents various design criteria for the instrument and describes the major features of the microscope components-the cooled CCD camera and the MetaMorph digital imaging system. The Nikon FXA upright microscope can produce high resolution images for both epifluorescent and transmitted light illumination without switching the objective or moving the specimen. The functional aspects of the microscope set-up can be considered in terms of the imaging optics, the epi-illumination optics, the transillumination optics, the focus control, and the vibration isolation table. This instrument is somewhat specialized for microtubule and mitosis studies, and it is also applicable to a variety of problems in cellular imaging, including tracking proteins fused to the green fluorescent protein in live cells. The instrument is also valuable for correlating the assembly dynamics of individual cytoplasmic microtubules (labeled by conjugating X-rhodamine to tubulin) with the dynamics of membranes of the endoplasmic reticulum (labeled with DiOC6) and the dynamics of the cell cortex (by differential interference contrast) in migrating vertebrate epithelial cells. This imaging system also plays an important role in the analysis of mitotic mutants in the powerful yeast genetic system Saccharomyces cerevisiae.

  13. Improved Spatial Resolution For Reflection Mode Infrared Spectromicroscopy

    SciTech Connect

    Bechtel, Hans A; Martin, Michael C.; May, T. E.; Lerch, Philippe

    2009-08-13

    Standard commercial infrared microscopes operating in reflection mode use a mirror to direct the reflected light from the sample to the detector. This mirror blocks about half of the incident light, however, and thus degrades the spatial resolution by reducing the numerical aperture of the objective. Here, we replace the mirror with a 50% beamsplitter to allow full illumination of the objective and retain a way to direct the reflected light to the detector. The improved spatial resolution is demonstrated using a microscope coupled to a synchrotron source.

  14. Improved Spatial Resolution For Reflection Mode Infrared Spectromicroscopy

    SciTech Connect

    Bechtel, Hans A.; Martin, Michael C.; May, T. E.; Lerch, Philippe

    2010-02-03

    Standard commercial infrared microscopes operating in reflection mode use a mirror to direct the reflected light from the sample to the detector. This mirror blocks about half of the incident light, however, and thus degrades the spatial resolution by reducing the numerical aperture of the objective. Here, we replace the mirror with a 50% beamsplitter to allow full illumination of the objective and retain a way to direct the reflected light to the detector. The improved spatial resolution is demonstrated using a microscope coupled to a synchrotron source.

  15. The Athena Microscopic Imager Investigation

    NASA Technical Reports Server (NTRS)

    Herkenhoff, K. E.; Aquyres, S. W.; Bell, J. F., III; Maki, J. N.; Arneson, H. M.; Brown, D. I.; Collins, S. A.; Dingizian, A.; Elliot, S. T.; Geotz, W.

    2003-01-01

    The Athena science payload on the Mars Exploration Rovers (MER) includes the Microscopic Imager (MI) [1]. The MI is a fixed-focus camera mounted on the end of an extendable instrument arm, the Instrument Deployment Device (IDD; see Figure 1).The MI was designed to acquire images at a spatial resolution of 30 microns/pixel over a broad spectral range (400 - 700 nm; see Table 1). Technically, the microscopic imager is not a microscope: it has a fixed magnification of 0.4 and is intended to produce images that simulate a geologist s view through a common hand lens. In photographers parlance, the system makes use of a macro lens. The MI uses the same electronics design as the other MER cameras [2, 3] but has optics that yield a field of view of 31 31 mm across a 1024 1024 pixel CCD image (Figure 2). The MI acquires images using only solar or skylightillumination of the target surface. A contact sensor is used to place the MI slightly closer to the target surface than its best focus distance (about 66 mm), allowing concave surfaces to be imaged in good focus. Because the MI has a relatively small depth of field (3 mm), a single MI image of a rough surface will contain both focused and unfocused areas. Coarse focusing will be achieved by moving the IDD away from a rock target after the contact sensor is activated. Multiple images taken at various distances will be acquired to ensure good focus on all parts of rough surfaces. By combining a set of images acquired in this way, a completely focused image can be assembled. Stereoscopic observations can be obtained by moving the MI laterally relative to its boresight. Estimates of the position and orientation of the MI for each acquired image will be stored in the rover computer and returned to Earth with the image data. The MI optics will be protected from the Martian environment by a retractable dust cover. The dust cover includes a Kapton window that is tinted orange to restrict the spectral bandpass to 500-700 nm

  16. Inclined Selective Plane Illumination Microscopy (iSPIM) adaptor for conventional microscopes

    PubMed Central

    Cutrale, Francesco; Gratton, Enrico

    2013-01-01

    There is a current need in biomedical sciences to perform live imaging with higher spatial and temporal resolution. To achieve this goal in a comprehensive manner, three-dimensional acquisitions are necessary. Ideal features of a modern microscope system should include high imaging speed, high contrast ratio, low photo-bleaching and photo-toxicity, good resolution in a 3D context and mosaic acquisition for large samples. Considering the importance collecting data in live sample increases the technical challenges required to solve these issues. This work presents a practical version of a microscopy method, Selective Plane Illumination Microscopy reintroduced by Huisken (2004). This method is gaining importance in the biomedical field, with its load of technical solutions but has been limited by difficulties associated with unconventional microscope construction using two objectives and sample preparation. Based on the selective plane illumination principle but with a design similar to the Total Internal Reflection Fluorescence microscope, Dunsby (2008) demonstrated the Oblique Plane Microscope (OPM) using a single objective which uses conventional sample preparation protocols. However, the Dunsby instrument was not intended to be part of a commercial microscope. In this work we describe a system with the advantages of OPM and that can be used as an add-on to commonly used microscopes, such as IX-71 Olympus, simplifying the construction of the OPM and increasing performance of a conventional microscope. We named our design inclined Selective Plane Illumination Microscope (iSPIM). PMID:22736488

  17. Foldscope: Origami-Based Paper Microscope

    PubMed Central

    Cybulski, James S.; Clements, James; Prakash, Manu

    2014-01-01

    Here we describe an ultra-low-cost origami-based approach for large-scale manufacturing of microscopes, specifically demonstrating brightfield, darkfield, and fluorescence microscopes. Merging principles of optical design with origami enables high-volume fabrication of microscopes from 2D media. Flexure mechanisms created via folding enable a flat compact design. Structural loops in folded paper provide kinematic constraints as a means for passive self-alignment. This light, rugged instrument can survive harsh field conditions while providing a diversity of imaging capabilities, thus serving wide-ranging applications for cost-effective, portable microscopes in science and education. PMID:24940755

  18. Scanning evanescent electro-magnetic microscope

    DOEpatents

    Xiang, Xiao-Dong; Gao, Chen; Schultz, Peter G.; Wei, Tao

    2003-01-01

    A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.

  19. Scanning evanescent electro-magnetic microscope

    DOEpatents

    Xiang, Xiao-Dong; Gao, Chen

    2001-01-01

    A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.

  20. Lens design with suppressed first order reflections

    NASA Astrophysics Data System (ADS)

    Buchheister, Jan; Weth, Christopher

    2010-08-01

    Optical systems with a reflected light condition, e.g. microscopes with reflected light illumination or fundus cameras, need to have weak first order ghosts or even to be completely free from them. Sequential ray tracing can be used to control optical performance and reflections on a ray basis during optimization. This is significantly more efficient in computation time and convergence than the usual approaches with non-sequential ray tracing or reconfigured optical systems to cover all critical ghosts. An ophthalmic lens for a fundus camera was designed with first order reflections stripped out by applying sequential ray tracing. The merit-function only had to be completed under certain conditions guaranteeing the absence of any reflections. No additional reconfiguration of the optical system in the design software was necessary.

  1. Reflected Ceiling Plan/Reflected Deck Plan 2009; Reflected Ceiling Plan/Reflected Deck ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Reflected Ceiling Plan/Reflected Deck Plan 2009; Reflected Ceiling Plan/Reflected Deck Plan 2010 - Gilpin's Falls Covered Bridge, Spanning North East Creek at Former (Bypassed) Section of North East Road (SR 272), North East, Cecil County, MD

  2. Experimental observation of plastic deformation areas, using an acoustic microscope.

    PubMed

    Ishikawa, I; Semba, T; Kanda, H; Katakura, K; Tani, Y; Sato, H

    1989-01-01

    Novel techniques are described for the observation of plastic deformation areas by using an acoustic microscope. On a test piece subjected to plastic deformation, an area was found that had an abnormal contrast in the crystal grain and a pointed end at the V notch. Calculation of the propagation velocity of the surface acoustic wave (SAW) showed a difference of several percent between this area and the rest of the test piece. It has been presumed that this difference reflects the local plastic deformation, and that the abnormal contrast area corresponds to the image of the two-dimensionally distributed plastic deformation area of metals.

  3. Mars Under the Microscope (stretched)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This magnified look at the martian soil near the Mars Exploration Rover Opportunity's landing site, Meridiani Planum, shows coarse grains sprinkled over a fine layer of sand. The image was captured on the 10th day, or sol, of the rover's mission by its microscopic imager, located on the instrument deployment device, or 'arm.' Scientists are intrigued by the spherical rocks, which can be formed by a variety of geologic processes, including cooling of molten lava droplets and accretion of concentric layers of material around a particle or 'seed.'

    The examined patch of soil is 3 centimeters (1.2 inches) across. The circular grain in the lower left corner is approximately 3 millimeters (.12 inches) across, or about the size of a sunflower seed.

    This stretched color composite was obtained by merging images acquired with the orange-tinted dust cover open and closed. The varying hints of orange suggest differences in mineral composition. The blue tint at the lower right corner is a tag used by scientists to indicate that the dust cover is closed.

  4. Mars Under the Microscope (color)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This magnified look at the martian soil near the Mars Exploration Rover Opportunity's landing site, Meridiani Planum, shows coarse grains sprinkled over a fine layer of sand. The image was captured by the rover's microscopic imager on the 10th day, or sol, of its mission and roughly approximates the color a human eye would see. Scientists are intrigued by the spherical rocks, which can be formed by a variety of geologic processes, including cooling of molten lava droplets and accretion of concentric layers of material around a particle or 'seed.'

    The examined patch of soil is 3 centimeters (1.2 inches) across. The circular grain in the lower left corner is approximately 3 millimeters (.12 inches) across, or about the size of a sunflower seed.

    This color composite was obtained by merging images acquired with the orange-tinted dust cover in both its open and closed positions. The blue tint at the lower right corner is a tag used by scientists to indicate that the dust cover is closed.

  5. Spectral Interferometry with Electron Microscopes.

    PubMed

    Talebi, Nahid

    2016-09-21

    Interference patterns are not only a defining characteristic of waves, but also have several applications; characterization of coherent processes and holography. Spatial holography with electron waves, has paved the way towards space-resolved characterization of magnetic domains and electrostatic potentials with angstrom spatial resolution. Another impetus in electron microscopy has been introduced by ultrafast electron microscopy which uses pulses of sub-picosecond durations for probing a laser induced excitation of the sample. However, attosecond temporal resolution has not yet been reported, merely due to the statistical distribution of arrival times of electrons at the sample, with respect to the laser time reference. This is however, the very time resolution which will be needed for performing time-frequency analysis. These difficulties are addressed here by proposing a new methodology to improve the synchronization between electron and optical excitations through introducing an efficient electron-driven photon source. We use focused transition radiation of the electron as a pump for the sample. Due to the nature of transition radiation, the process is coherent. This technique allows us to perform spectral interferometry with electron microscopes, with applications in retrieving the phase of electron-induced polarizations and reconstructing dynamics of the induced vector potential.

  6. Microscopic theory of rubber elasticity.

    PubMed

    Oyerokun, Folusho T; Schweizer, Kenneth S

    2004-05-15

    A microscopic integral equation theory of elasticity in polymer liquids and networks is developed which addresses the nonclassical problem of the consequences of interchain repulsive interactions and packing correlations on mechanical response. The theory predicts strain induced softening, and a nonclassical intermolecular contribution to the linear modulus. The latter is of the same magnitude as the classical single chain entropy contribution at low polymer concentrations, but becomes much more important in the melt state, and dominant as the isotropic-nematic liquid crystal phase transition is approached. Comparison of the calculated stress-strain curve and induced nematic order parameter with computer simulations show good agreement. A nearly quadratic dependence of the linear elastic modulus on segmental concentration is found, as well as a novel fractional power law dependence on degree of polymerization. Quantitative comparison of the theory with experiments on polydimethylsiloxane networks are presented and good agreement is found. However, a nonzero modulus in the long chain limit is not predicted since quenched chemical crosslinks and trapped entanglements are not explicitly taken into account. The theory is generalizable to treat the structure, thermodynamics and mechanical response of nematic elastomers.

  7. Spectral Interferometry with Electron Microscopes

    PubMed Central

    Talebi, Nahid

    2016-01-01

    Interference patterns are not only a defining characteristic of waves, but also have several applications; characterization of coherent processes and holography. Spatial holography with electron waves, has paved the way towards space-resolved characterization of magnetic domains and electrostatic potentials with angstrom spatial resolution. Another impetus in electron microscopy has been introduced by ultrafast electron microscopy which uses pulses of sub-picosecond durations for probing a laser induced excitation of the sample. However, attosecond temporal resolution has not yet been reported, merely due to the statistical distribution of arrival times of electrons at the sample, with respect to the laser time reference. This is however, the very time resolution which will be needed for performing time-frequency analysis. These difficulties are addressed here by proposing a new methodology to improve the synchronization between electron and optical excitations through introducing an efficient electron-driven photon source. We use focused transition radiation of the electron as a pump for the sample. Due to the nature of transition radiation, the process is coherent. This technique allows us to perform spectral interferometry with electron microscopes, with applications in retrieving the phase of electron-induced polarizations and reconstructing dynamics of the induced vector potential. PMID:27649932

  8. Mars Under the Microscope (stretched)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This magnified look at the martian soil near the Mars Exploration Rover Opportunity's landing site, Meridiani Planum, shows coarse grains sprinkled over a fine layer of sand. The image was captured on the 10th day, or sol, of the rover's mission by its microscopic imager, located on the instrument deployment device, or 'arm.' Scientists are intrigued by the spherical rocks, which can be formed by a variety of geologic processes, including cooling of molten lava droplets and accretion of concentric layers of material around a particle or 'seed.'

    The examined patch of soil is 3 centimeters (1.2 inches) across. The circular grain in the lower left corner is approximately 3 millimeters (.12 inches) across, or about the size of a sunflower seed.

    This stretched color composite was obtained by merging images acquired with the orange-tinted dust cover open and closed. The varying hints of orange suggest differences in mineral composition. The blue tint at the lower right corner is a tag used by scientists to indicate that the dust cover is closed.

  9. Mars Under the Microscope (color)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This magnified look at the martian soil near the Mars Exploration Rover Opportunity's landing site, Meridiani Planum, shows coarse grains sprinkled over a fine layer of sand. The image was captured by the rover's microscopic imager on the 10th day, or sol, of its mission and roughly approximates the color a human eye would see. Scientists are intrigued by the spherical rocks, which can be formed by a variety of geologic processes, including cooling of molten lava droplets and accretion of concentric layers of material around a particle or 'seed.'

    The examined patch of soil is 3 centimeters (1.2 inches) across. The circular grain in the lower left corner is approximately 3 millimeters (.12 inches) across, or about the size of a sunflower seed.

    This color composite was obtained by merging images acquired with the orange-tinted dust cover in both its open and closed positions. The blue tint at the lower right corner is a tag used by scientists to indicate that the dust cover is closed.

  10. Microscopic structure of gelatin coacervates.

    PubMed

    Mohanty, Biswaranjan; Bohidar, H B

    2005-07-01

    Microscopic structure of simple coacervates of gelatin having concentration approximately 130 g/l were studied at 25 degrees C by atomic force microscopy (AFM), rheology, small angle neutron scattering (SANS), UV absorption and circular dichroism (CD) techniques. The behavior of viscoelastic exponents Delta' and Delta'' of storage and loss modulii (G'(omega) approximately omega Delta', G''(omega) approximately omega Delta") revealed that, Delta' = 0.25+/-0.01 and Delta'' = 0.78+/-0.1 for coacervates. The mass fractal dimension 'd(f)' for coacervate was found to be 2.27, which attributed a compact heterogeneous network structure to the coacervates. This is supported by AFM pictures. The CD and UV absorption data indicated presence of helical structures inside the coacervates phase. SANS results showed the existence of a single length scale associated with this system identified as gelatin persistence length, zeta = 27+/-2 A. These studies indicate that the coacervate phase is a low dimensional dense heterogeneous material comprised of strongly interconnected triple helices which imparts a large storage modulus to this material.

  11. Quantitative determination of two polymorphic forms of imatinib mesylate in a drug substance and tablet formulation by X-ray powder diffraction, differential scanning calorimetry and attenuated total reflectance Fourier transform infrared spectroscopy.

    PubMed

    Bellur Atici, Esen; Karlığa, Bekir

    2015-10-10

    Imatinib has been identified as a tyrosine kinase inhibitor that selectively inhibits the Abl tyrosine kinases, including Bcr-Abl. The active substance used in drug product is the mesylate salt form of imatinib, a phenylaminopyrimidine derivative and chemically named as N-(3-(4-(pyridin-3-yl) pyrimidin-2-ylamino)-4-methylphenyl)-4-((4-methylpiperazin-1-yl) methyl)-benzamide methanesulfonic acid salt. It exhibits many polymorphic forms and most stable and commercialized polymorphs are known as α and β forms. Molecules in α and β polymorphic forms exhibit significant conformational differences due to their different intra- and intermolecular interactions, which stabilize their molecular conformations and affect their physicochemical properties such as bulk density, melting point, solubility, stability, and processability. The manufacturing process of a drug tablet included granulation, compression, coating, and drying may cause polymorphic conversions. Therefore, polymorphic content of the drug substance should be controlled during quality control and stability testing. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD) methods were evaluated for determination of the polymorphic content of the drug substance and drug product; and PXRD was the most accurate technique and selected as preferred method and validated. Prior to development of a quantification method, pure α and β polymorphs were characterized and used throughout the method development and validation studies. Mixtures with different ratios of α and β forms were scanned using X-ray diffractometer with a scan rate of 0.250°/min over an angular range of 19.5-21.0° 2θ and the peak heights for characteristic peak of β form at 20.5 ± 0.2° 2θ diffraction angle were used to generate a calibration curve. The detection limit of β polymorph in α form imatinib mesylate tablets was found as 4% and

  12. Identification of ex-vivo confocal scanning microscopic features and their histological correlates in human skin.

    PubMed

    Hartmann, Daniela; Ruini, Cristel; Mathemeier, Leonie; Dietrich, Andreas; Ruzicka, Thomas; von Braunmühl, Tanja

    2016-04-01

    Ex-vivo confocal laser scanning microscopy (CLSM) is an emerging diagnostic tool allowing fast and easy microscopic tissue examination. The first generation of ex-vivo devices have already shown promising results in the ex-vivo evaluation of basal cell carcinoma compared to Mohs surgery. Nevertheless, for the diagnostics of pathological skin lesions the knowledge of normal skin features is essential. Therefore we examined 50 samples of healthy skin from various donor sites including head and neck (n = 25), trunk (n = 10), upper (n = 10) and lower extremities (n = 5) using a new generation ex-vivo CLSM device offering three different laser wavelengths and compared the findings to the corresponding histological sections. In correlation with the histopathology we identified different layers of the epidermis, differentiated keratinocytes from melanocytes and described in detail skin appendages including hair follicle, sebaceous and sweat glands. Furthermore, structures of the dermis and subcutis were illustrated. Additionally, artefacts and pitfalls occurring with the use of ex-vivo CLSM have been documented. The study offers an overview of the main ex-vivo CLSM skin characteristics in comparison to the standard histological examination and helps to recognize and avoid common artefacts. Anatomy of a hair follicle in the reflectance mode (RM) CLSM, fluorescence mode (FM) CLSM and in a routine hematoxylin-eosin stained histological section (H). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Electron Microscope Center Opens at Berkeley.

    ERIC Educational Resources Information Center

    Robinson, Arthur L.

    1981-01-01

    A 1.5-MeV High Voltage Electron Microscope has been installed at the Lawrence Berkeley Laboratory which will help materials scientists and biologists study samples in more true-to-life situations. A 1-MeV Atomic Resolution Microscope will be installed at the same location in two years which will allow scientists to distinguish atoms. (DS)

  14. Electron Microscope Center Opens at Berkeley.

    ERIC Educational Resources Information Center

    Robinson, Arthur L.

    1981-01-01

    A 1.5-MeV High Voltage Electron Microscope has been installed at the Lawrence Berkeley Laboratory which will help materials scientists and biologists study samples in more true-to-life situations. A 1-MeV Atomic Resolution Microscope will be installed at the same location in two years which will allow scientists to distinguish atoms. (DS)

  15. Robotic CCD microscope for enhanced crystal recognition

    DOEpatents

    Segelke, Brent W.; Toppani, Dominique

    2007-11-06

    A robotic CCD microscope and procedures to automate crystal recognition. The robotic CCD microscope and procedures enables more accurate crystal recognition, leading to fewer false negative and fewer false positives, and enable detection of smaller crystals compared to other methods available today.

  16. Testing the link between population genetic differentiation and clade diversification in Costa Rican orchids.

    PubMed

    Kisel, Yael; Moreno-Letelier, Alejandra C; Bogarín, Diego; Powell, Martyn P; Chase, Mark W; Barraclough, Timothy G

    2012-10-01

    Species population genetics could be an important factor explaining variation in clade species richness. Here, we use newly generated amplified fragment length polymorphism (AFLP) data to test whether five pairs of sister clades of Costa Rican orchids that differ greatly in species richness also differ in average neutral genetic differentiation within species, expecting that if the strength of processes promoting differentiation within species is phylogenetically heritable, then clades with greater genetic differentiation should diversify more. Contrary to expectation, neutral genetic differentiation does not correlate directly with total diversification in the clades studied. Neutral genetic differentiation varies greatly among species and shows no heritability within clades. Half of the variation in neutral genetic differentiation among populations can be explained by ecological variables, and species-level traits explain the most variation. Unexpectedly, we find no isolation by distance in any species, but genetic differentiation is greater between populations occupying different niches. This pattern corresponds with those observed for microscopic eukaryotes and could reflect effective widespread dispersal of tiny and numerous orchid seeds. Although not providing a definitive answer to whether population genetics processes affect clade diversification, this work highlights the potential for addressing new macroevolutionary questions using a comparative population genetic approach. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  17. Scanning optical microscope with long working distance objective

    DOEpatents

    Cloutier, Sylvain G.

    2010-10-19

    A scanning optical microscope, including: a light source to generate a beam of probe light; collimation optics to substantially collimate the probe beam; a probe-result beamsplitter; a long working-distance, infinity-corrected objective; scanning means to scan a beam spot of the focused probe beam on or within a sample; relay optics; and a detector. The collimation optics are disposed in the probe beam. The probe-result beamsplitter is arranged in the optical paths of the probe beam and the resultant light from the sample. The beamsplitter reflects the probe beam into the objective and transmits resultant light. The long working-distance, infinity-corrected objective is also arranged in the optical paths of the probe beam and the resultant light. It focuses the reflected probe beam onto the sample, and collects and substantially collimates the resultant light. The relay optics are arranged to relay the transmitted resultant light from the beamsplitter to the detector.

  18. Design of a normal incidence multilayer imaging x-ray microscope.

    PubMed

    Shealy, D L; Gabardi, D R; Hoover, R B; Walker, A B; Lindblom, J F; Barbee, T W

    1989-01-01

    Normal incidence multilayer Cassegrain x-ray telescopes were flown on the Stanford/MSFC Rocket X-Ray Spectroheliograph. These instruments produced high spatial resolution images of the Sun and conclusively demonstrated that doubly reflecting multilayer x-ray optical systems are feasible. The images indicated that aplanatic imaging soft x-ray /EUV microscopes should be achievable using multilayer optics technology. We have designed a doubly reflecting normal incidence multilayer imaging x-ray microscope based on the Schwarzschild configuration. The Schwarzschild microscope utilizes two spherical mirrors with concentric radii of curvature which are chosen such that the third-order spherical aberration and coma are minimized. We discuss the design of the microscope and the results of the optical system ray trace analysis which indicates that diffraction-limited performance with 600 Å spatial resolution should be obtainable over a 1 mm field of view at a wavelength of 100 Å. Fabrication of several imaging soft x-ray microscopes based upon these designs, for use in conjunction with x-ray telescopes and laser fusion research, is now in progress. High resolution aplanatic imaging x-ray microscopes using normal incidence multilayer x-ray mirrors should have many important applications in advanced x-ray astronomical instrumentation, x-ray lithography, biological, biomedical, metallurgical, and laser fusion research.

  19. Development of a high-energy Kirkpatrick Baez microscope

    NASA Astrophysics Data System (ADS)

    Li, Yaran; Mu, Baozhong; Xie, Qing; Wang, Xin; Wang, Zhanshan

    2016-09-01

    X-ray imaging of the laser produced plasma plays an important role in plasma diagnostics. Based on the urgent needs of conducting deeper and finer physical experiments, we developed a high-energy Kirkpatrick Baez microscope working at 17.48keV with a spectral resolution (E/▵E) of 30. The concave spherical substrates was polished, ultrasonically cleaned and coated. The substrates have a radius of curvature of 20m with a roughness better than 0.3nm. The grazing incidence angles are designed at 0.7° and 0.73° for separate reflecting mirrors. The x-ray backlit imaging experiments show its spatial resolution is 5.5μm at best focus. The effective field of view is measured to be 90μm, which is consistent with the multilayer design. This article provides detailed informations for the optical design, multilayers coating and characterization of the microscope. The microscope promises to be a high-energy, high-resolution, and energy resolved X-ray diagnostics instrument for SG series laser facility.

  20. Measurement Uncertainty of Microscopic Laser Triangulation on Technical Surfaces.

    PubMed

    Mueller, Thomas; Poesch, Andreas; Reithmeier, Eduard

    2015-12-01

    Laser triangulation is widely used to measure three-dimensional structure of surfaces. The technique is suitable for macroscopic and microscopic surface measurements. In this paper, the measurement uncertainty of laser triangulation is investigated on technical surfaces for microscopic measurement applications. Properties of technical surfaces are, for example, reflectivity, surface roughness, and the presence of scratches and pores. These properties are more influential in the microscopic laser triangulation than in the macroscopic one. In the Introduction section of this paper, the measurement uncertainty of laser triangulation is experimentally investigated for 13 different specimens. The measurements were carried out with and without a laser speckle reducer. In the Materials and Methods section of this paper, the surfaces of the 13 specimens are characterized in order to be able to find correlations between the surface properties and the measurement uncertainty. The last section of this paper describes simulations of the measurement uncertainty, which allow for the calculation of the measurement uncertainty with only one source of uncertainty present. The considerations in this paper allow for the assessment of the measurement uncertainty of laser triangulation on any technical surface when some surface properties, such as roughness, are known.

  1. Sensing of Streptococcus mutans by microscopic imaging ellipsometry

    NASA Astrophysics Data System (ADS)

    Khaleel, Mai Ibrahim; Chen, Yu-Da; Chien, Ching-Hang; Chang, Yia-Chung

    2017-05-01

    Microscopic imaging ellipsometry is an optical technique that uses an objective and sensing procedure to measure the ellipsometric parameters Ψ and Δ in the form of microscopic maps. This technique is well known for being noninvasive and label-free. Therefore, it can be used to detect and characterize biological species without any impact. Microscopic imaging ellipsometry was used to measure the optical response of dried Streptococcus mutans cells on a glass substrate. The ellipsometric Ψ and Δ maps were obtained with the Optrel Multiskop system for specular reflection in the visible range (λ=450 to 750 nm). The Ψ and Δ images at 500, 600, and 700 nm were analyzed using three different theoretical models with single-bounce, two-bounce, and multibounce light paths to obtain the optical constants and height distribution. The obtained images of the optical constants show different aspects when comparing the single-bounce analysis with the two-bounce or multibounce analysis in detecting S. mutans samples. Furthermore, the height distributions estimated by two-bounce and multibounce analyses of S. mutans samples were in agreement with the thickness values measured by AFM, which implies that the two-bounce and multibounce analyses can provide information complementary to that obtained by a single-bounce light path.

  2. The current status of microscopical hair comparisons.

    PubMed

    Rowe, W F

    2001-12-08

    Although the microscopical comparison of human hairs has been accepted in courts of law for over a century, recent advances in DNA technology have called this type of forensic examination into question. In a number of cases, post-conviction DNA testing has exonerated defendants who were convicted in part on the results of microscopical hair comparisons. A federal judge has held a Daubert hearing on the microscopical comparison of human hairs and has concluded that this type of examination does not meet the criteria for admission of scientific evidence in federal courts. A review of the available scientific literature on microscopical hair comparisons (including studies conducted by the Royal Canadian Mounted Police and the Federal Bureau of Investigation) leads to three conclusions: (1) microscopical comparisons of human hairs can yield scientifically defensible conclusions that can contribute to criminal investigations and criminal prosecutions, (2) the reliability of microscopical hair comparisons is strongly affected by the training of the forensic hair examiner, (3) forensic hair examiners cannot offer estimates of the probability of a match of a questioned hair with a hair from a randomly selected person. In order for microscopical hair examinations to survive challenges under the U.S. Supreme Court's Daubert decision, hair microscopists must be better trained and undergo frequent proficiency testing. More research on the error rates of microscopical hair comparisons should be undertaken, and guidelines for the permissible interpretations of such comparisons should be established. Until these issues have been addressed and satisfactorily resolved, microscopical hair comparisons should be regarded by law enforcement agencies and courts of law as merely presumptive in nature, and all microscopical hair comparisons should be confirmed by nuclear DNA profiling or mitochondrial DNA sequencing.

  3. Josephson flux-flow oscillator: The microscopic tunneling approach

    NASA Astrophysics Data System (ADS)

    Gulevich, D. R.; Koshelets, V. P.; Kusmartsev, F. V.

    2017-07-01

    We elaborate a theoretical description of large Josephson junctions which is based on Werthamer's microscopic tunneling theory. The model naturally incorporates coupling of electromagnetic radiation to the tunnel currents and, therefore, is particularly suitable for description of the self-coupling effect in Josephson junction. In our numerical calculations we treat the arising integro-differential equation, which describes temporal evolution of the superconducting phase difference coupled to the electromagnetic field, by the Odintsov-Semenov-Zorin algorithm. This allows us to avoid evaluation of the time integrals at each time step while taking into account all the memory effects. To validate the obtained microscopic model of large Josephson junction we focus our attention on the Josephson flux-flow oscillator. The proposed microscopic model of flux-flow oscillator does not involve the phenomenological damping parameter, rather the damping is taken into account naturally in the tunnel current amplitudes calculated at a given temperature. The theoretically calculated current-voltage characteristics is compared to our experimental results obtained for a set of fabricated flux-flow oscillators of different lengths.

  4. Challenging Narcissus, or Reflecting on Reflecting.

    ERIC Educational Resources Information Center

    Achilles, C. M.

    The concept of reflective practice and teaching people to be reflective practitioners is examined. The document begins with a look at professional knowledge according to three prominent professionals in the educational administration field: Schon, Schein, and Achilles. "Reflective" strategies that could be incorporated into courses and…

  5. Quality Self-Reflection through Reflection Training

    ERIC Educational Resources Information Center

    Gun, Bahar

    2011-01-01

    This research study discusses the importance of "reflection training" in teacher education programmes. The main premise of the study is that although teachers are constantly encouraged to "reflect" on their teaching, they are unable to do so effectively unless they are specifically trained in how to reflect (they tend to "react" rather than…

  6. The Scanning Optical Microscope: An Overview

    NASA Astrophysics Data System (ADS)

    Kino, G. S.; Corte, T. R.; Xiao, G. Q.

    1988-07-01

    In the last few years there has been a resurgence in research on optical microscopes. One reason stems from the invention of the acoustic microscope by Quate and Lemons,1 and the realization that some of the same principles could be applied to the optical microscope. The acoustic microscope has better transverse definition for the same wavelength than the standard optical microscope and at the same time has far better range definition. Consequently, Kompfner, who was involved with the work on the early acoustic microscope, decided to try out similar scanning microscope principles with optics, and started a group with Wilson and Sheppard to carry out such research at Oxford.2 Sometime earlier, Petran et a13 had invented the tandem scanning microscope which used many of the same principles. Now, in our laboratory at Stanford, these ideas on the tandem scanning microscope and the scanning optical microscope are converging. Another aspect of this work, which stems from the earlier experience with the acoustic microscope, involves measurement of both phase and amplitude of the optical beam. It is also possible to use scanned optical microscopy for other purposes. For instance, an optical beam can be used to excite electrons and holes in semiconductors, and the generated current can be measured. By scanning the optical beam over the semiconductor, an image can be obtained of the regions where there is strong or weak electron hole generation. This type of microscope is called OBIC (Optical Beam Induced Current). A second application involves fluorescent imaging of biological materials. Here we have the excellent range definition of a scanning optical microscope which eliminates unwanted glare from regions of the material where the beam is unfocused.3 A third application is focused on the heating effect of the light beam. With such a system, images can be obtained which are associated with changes in the thermal properties of a material, changes in recombination rates in

  7. Atomic Force Microscope Mediated Chromatography

    NASA Technical Reports Server (NTRS)

    Anderson, Mark S.

    2013-01-01

    The atomic force microscope (AFM) is used to inject a sample, provide shear-driven liquid flow over a functionalized substrate, and detect separated components. This is demonstrated using lipophilic dyes and normal phase chromatography. A significant reduction in both size and separation time scales is achieved with a 25-micron-length column scale, and one-second separation times. The approach has general applications to trace chemical and microfluidic analysis. The AFM is now a common tool for ultra-microscopy and nanotechnology. It has also been demonstrated to provide a number of microfluidic functions necessary for miniaturized chromatography. These include injection of sub-femtoliter samples, fluidic switching, and sheardriven pumping. The AFM probe tip can be used to selectively remove surface layers for subsequent microchemical analysis using infrared and tip-enhanced Raman spectroscopy. With its ability to image individual atoms, the AFM is a remarkably sensitive detector that can be used to detect separated components. These diverse functional components of microfluidic manipulation have been combined in this work to demonstrate AFM mediated chromatography. AFM mediated chromatography uses channel-less, shear-driven pumping. This is demonstrated with a thin, aluminum oxide substrate and a non-polar solvent system to separate a mixture of lipophilic dyes. In conventional chromatographic terms, this is analogous to thin-layer chromatography using normal phase alumina substrate with sheardriven pumping provided by the AFM tip-cantilever mechanism. The AFM detection of separated components is accomplished by exploiting the variation in the localized friction of the separated components. The AFM tip-cantilever provides the mechanism for producing shear-induced flows and rapid pumping. Shear-driven chromatography (SDC) is a relatively new concept that overcomes the speed and miniaturization limitations of conventional liquid chromatography. SDC is based on a

  8. A desktop extreme ultraviolet microscope based on a compact laser-plasma light source

    NASA Astrophysics Data System (ADS)

    Wachulak, P. W.; Torrisi, A.; Bartnik, A.; Węgrzyński, Ł.; Fok, T.; Fiedorowicz, H.

    2017-01-01

    A compact, desktop size microscope, based on laser-plasma source and equipped with reflective condenser and diffractive Fresnel zone plate objective, operating in the extreme ultraviolet (EUV) region at the wavelength of 13.8 nm, was developed. The microscope is capable of capturing magnified images of objects with 95-nm full-pitch spatial resolution (48 nm 25-75% KE) and exposure time as low as a few seconds, combining reasonable acquisition conditions with stand-alone desktop footprint. Such EUV microscope can be regarded as a complementary imaging tool to already existing, well-established ones. Details about the microscope, characterization, resolution estimation and real sample images are presented and discussed.

  9. Calibrated nanoscale capacitance measurements using a scanning microwave microscope.

    PubMed

    Huber, H P; Moertelmaier, M; Wallis, T M; Chiang, C J; Hochleitner, M; Imtiaz, A; Oh, Y J; Schilcher, K; Dieudonne, M; Smoliner, J; Hinterdorfer, P; Rosner, S J; Tanbakuchi, H; Kabos, P; Kienberger, F

    2010-11-01

    A scanning microwave microscope (SMM) for spatially resolved capacitance measurements in the attofarad-to-femtofarad regime is presented. The system is based on the combination of an atomic force microscope (AFM) and a performance network analyzer (PNA). For the determination of absolute capacitance values from PNA reflection amplitudes, a calibration sample of conductive gold pads of various sizes on a SiO(2) staircase structure was used. The thickness of the dielectric SiO(2) staircase ranged from 10 to 200 nm. The quantitative capacitance values determined from the PNA reflection amplitude were compared to control measurements using an external capacitance bridge. Depending on the area of the gold top electrode and the SiO(2) step height, the corresponding capacitance values, as measured with the SMM, ranged from 0.1 to 22 fF at a noise level of ~2 aF and a relative accuracy of 20%. The sample capacitance could be modeled to a good degree as idealized parallel plates with the SiO(2) dielectric sandwiched in between. The cantilever/sample stray capacitance was measured by lifting the tip away from the surface. By bringing the AFM tip into direct contact with the SiO(2) staircase structure, the electrical footprint of the tip was determined, resulting in an effective tip radius of ~60 nm and a tip-sample capacitance of ~20 aF at the smallest dielectric thickness.

  10. Multispectral assessment of skin malformations using a modified video-microscope

    NASA Astrophysics Data System (ADS)

    Bekina, A.; Diebele, I.; Rubins, U.; Zaharans, J.; Derjabo, A.; Spigulis, J.

    2012-10-01

    A simplified method is proposed for alternative clinical diagnostics of skin malformations. A modified digital microscope, additionally equipped with a fourcolour LED (450 nm, 545 nm, 660 nm and 940 nm) subsequent illumination system, was applied for assessment of skin cancerous lesions and cutaneous inflammations. Multispectral image analysis was performed to map distributions of skin erythema index, bilirubin index, melanoma/nevus differentiation parameter, and fluorescence indicator. The skin malformation monitoring has shown that it is possible to differentiate melanoma from other pathologies.

  11. In vivo confocal microscopy of corneal microscopic foreign bodies in horses.

    PubMed

    Ledbetter, Eric C; Irby, Nita L; Schaefer, Deanna M W

    2014-07-01

    To describe in vivo corneal confocal microscopy of horses with microscopic corneal foreign bodies and to correlate findings with clinical, cytological, and histopathologic evaluations of clinical cases and foreign body morphologies observed in vitro with the confocal microscope. Five horses with microscopic corneal foreign bodies. Sedated and anesthetized horses were examined with a modified Heidelberg Retina Tomograph II and Rostock Cornea Module. Confocal microscopy images were compared with images from cytologic and histopathologic corneal samples. To establish microscopic morphologic features, confocal microscopy images of burdock pappus bristles and surgical glove powder were obtained by in vitro examination. Horses were examined by in vivo confocal microscopy to assist in identifying corneal opacities detected by slit-lamp biomicroscopy, to determine the etiology of clinically idiopathic keratitis, or to localize corneal opacities presumed to be foreign bodies for surgical planning. Corneal foreign bodies presumptively identified by confocal microscopy included burdock pappus bristles, other plant foreign materials, and surgical glove powder. The corneal foreign bodies appeared as moderately or hyper-reflective linear, circular, or oval structures by confocal microscopy and did not resemble any normal anatomic structures. The confocal microscopic identification of the foreign bodies was corroborated by cytologic and histopathologic findings in some horses. The in vivo confocal microscopic appearance of the foreign bodies was consistent with morphologies observed during examination of foreign bodies in vitro. In vivo corneal confocal microscopy provides a noninvasive method for the detection, characterization, and localization of microscopic foreign bodies in the equine cornea. © 2014 American College of Veterinary Ophthalmologists.

  12. Automatic Focus Adjustment of a Microscope

    NASA Technical Reports Server (NTRS)

    Huntsberger, Terrance

    2005-01-01

    AUTOFOCUS is a computer program for use in a control system that automatically adjusts the position of an instrument arm that carries a microscope equipped with an electronic camera. In the original intended application of AUTOFOCUS, the imaging microscope would be carried by an exploratory robotic vehicle on a remote planet, but AUTOFOCUS could also be adapted to similar applications on Earth. Initially control software other than AUTOFOCUS brings the microscope to a position above a target to be imaged. Then the instrument arm is moved to lower the microscope toward the target: nominally, the target is approached from a starting distance of 3 cm in 10 steps of 3 mm each. After each step, the image in the camera is subjected to a wavelet transform, which is used to evaluate the texture in the image at multiple scales to determine whether and by how much the microscope is approaching focus. A focus measure is derived from the transform and used to guide the arm to bring the microscope to the focal height. When the analysis reveals that the microscope is in focus, image data are recorded and transmitted.

  13. Fast and Adaptive Auto-focusing Microscope

    NASA Astrophysics Data System (ADS)

    Obara, Takeshi; Igarashi, Yasunobu; Hashimoto, Koichi

    Optical microscopes are widely used in biological and medical researches. By using the microscope, we can observe cellular movements including intracellular ions and molecules tagged with fluorescent dyes at a high magnification. However, a freely motile cell easily escapes from a 3D field of view of the typical microscope. Therefore, we propose a novel auto-focusing algorithm and develop a auto-focusing and tracking microscope. XYZ positions of a microscopic stage are feedback controlled to focus and track the cell automatically. A bright-field image is used to estimate a cellular position. XY centroids are used to estimate XY positions of the tracked cell. To estimate Z position, we use a diffraction pattern around the cell membrane. This estimation method is so-called Depth from Diffraction (DFDi). However, this method is not robust for individual differences between cells because the diffraction pattern depends on each cellular shape. Therefore, in this study, we propose a real-time correction of DFDi by using 2D Laplacian of an intracellular area as a goodness of the focus. To evaluate the performance of our developed algorithm and microscope, we auto-focus and track a freely moving paramecium. In this experimental result, the paramecium is auto-focused and kept inside the scope of the microscope during 45s. The evaluated focal error is within 5µm, while a length and a thickness of the paramecium are about 200µm and 50µm, respectively.

  14. Assessment of asymptomatic microscopic hematuria in adults.

    PubMed

    Sharp, Victoria J; Barnes, Kerri T; Erickson, Bradley A

    2013-12-01

    Although routine screening for bladder cancer is not recommended, microscopic hematuria is often incidentally discovered by primary care physicians. The American Urological Association has published an updated guideline for the management of asymptomatic microscopic hematuria, which is defined as the presence of three or more red blood cells per high-power field visible in a properly collected urine specimen without evidence of infection. The most common causes of microscopic hematuria are urinary tract infection, benign prostatic hyperplasia, and urinary calculi. However, up to 5% of patients with asymptomatic microscopic hematuria are found to have a urinary tract malignancy. The risk of urologic malignancy is increased in men, persons older than 35 years, and persons with a history of smoking. Microscopic hematuria in the setting of urinary tract infection should resolve after appropriate antibiotic treatment; persistence of hematuria warrants a diagnostic workup. Dysmorphic red blood cells, cellular casts, proteinuria, elevated creatinine levels, or hypertension in the presence of microscopic hematuria should prompt concurrent nephrologic and urologic referral. The upper urinary tract is best evaluated with multiphasic computed tomography urography, which identifies hydronephrosis, urinary calculi, and renal and ureteral lesions. The lower urinary tract is best evaluated with cystoscopy for urethral stricture disease, benign prostatic hyperplasia, and bladder masses. Voided urine cytology is no longer recommended as part of the routine evaluation of asymptomatic microscopic hematuria, unless there are risk factors for malignancy.

  15. The Atomic Origin of the Reflection Law

    NASA Astrophysics Data System (ADS)

    Prytz, Kjell

    2016-12-01

    It will be demonstrated how the reflection law may be derived on an atomic basis using the plane wave approximation together with Huygens' principle. The model utilized is based on the electric dipole character of matter originating from its molecular constituents. This approach is not new but has, since it was first introduced by Ewald and Oseen in 1915, been applied and analyzed many times before. Here we develop the Ewald-Oseen model of reflection adapted for high school and early undergraduate students with a basic knowledge of microscopic material structure.

  16. Seismic isolation of an electron microscope

    SciTech Connect

    Godden, W.G.; Aslam, M.; Scalise, D.T.

    1980-01-01

    A unique two-stage dynamic-isolation problem is presented by the conflicting design requirements for the foundations of an electron microscope in a seismic region. Under normal operational conditions the microscope must be isolated from ambient ground noise; this creates a system extremely vulnerable to seismic ground motions. Under earthquake loading the internal equipment forces must be limited to prevent damage or collapse. An analysis of the proposed design solution is presented. This study was motivated by the 1.5 MeV High Voltage Electron Microscope (HVEM) to be installed at the Lawrence Berkeley Laboratory (LBL) located near the Hayward Fault in California.

  17. Microscopes for NASA's Phoenix Mars Lander

    NASA Technical Reports Server (NTRS)

    2007-01-01

    One part of the Microscopy, Electrochemistry, and Conductivity Analyzer instrument for NASA's Phoenix Mars Lander is a pair of telescopes with a special wheel (on the right in this photograph) for presenting samples to be inspected with the microscopes. A horizontally mounted optical microscope (on the left in this photograph) and an atomic force microscope will examine soil particles and possibly ice particles.

    The shapes and the size distributions of soil particles may tell scientists about environmental conditions the material has experienced. Tumbling rounds the edges. Repeated wetting and freezing causes cracking. Clay minerals formed during long exposure to water have distinctive, platy particles shapes.

  18. Mars Life? - Microscopic Egg-shaped Structures

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This electron microscope image shows egg-shaped structures, some of which may be possible microscopic fossils of Martian origin as discussed by NASA research published in the Aug. 16, 1996, issue of the journal Science. A two-year investigation found organic molecules, mineral features characteristic of biological activity and possible microscopic fossils such as these inside of an ancient Martian rock that fell to Earth as a meteorite. The largest possible fossils are less than 1/100th the diameter of a human hair in size while most are ten times smaller.

  19. The microscopes of Antoni van Leeuwenhoek.

    PubMed

    van Zuylen, J

    1981-03-01

    The seventeenth-century Dutch microscopist, Antoni van Leeuwenhoek, was the first man to make a protracted study of microscopical objects, and, unlike his contemporary Robert Hooke, he viewed by transmitted light. Leeuwenhoek made over 500 of his own, curious, simple microscopes, but now only nine are known to exist. The exact nature of the lenses Leeuwenhoek made, has for long been a puzzle. The existing microscopes have now been examined in detail, and their optical characteristics measured and tabulated. It is proposed that the lens of highest magnification, x 266, was made using a special blown bubble technique.

  20. A large granite stage and measuring microscope.

    NASA Technical Reports Server (NTRS)

    Alston-Garnjost, M.; Davis, J. W.; Dauber, P. M.; Smits, R. G.

    1971-01-01

    A stage and measuring microscope servocontrolled by a computer have been constructed. The travel of the stage is 0.5 x 0.5 m and the travel of the microscope objective is 7.5 cm. The measuring accuracy is 1 micron in the x-y plane and 5 microns along the z axis. The mechanical and optical construction of the stage and microscope, as well as the way in which the control electronics are organized, permit great flexibility of operation. Possible applications include the scanning and measuring of astronomical plates, the laying out of patterns of semiconductor devices of very large sizes, and the measurement of precision grids.