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Sample records for differential reflectance microscope

  1. 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.

  2. 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.

  3. 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.

  4. Forensic applications of microscopical infrared internal reflection spectroscopy

    NASA Astrophysics Data System (ADS)

    Tungol, Mary W.; Bartick, Edward G.; Reffner, John A.

    1994-01-01

    Applications of microscopical infrared internal reflection spectroscopy in forensic science are discussed. Internal reflection spectra of single fibers, hairs, paint chips, vehicle rubber bumpers, photocopy toners, carbon copies, writing ink on paper, lipstick on tissue, black electrical tape, and other types of forensic evidence have been obtained. The technique is convenient, non-destructive, and may permit smeared materials to be analyzed in situ.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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. PMID:20234540

  11. Dual-axes confocal reflectance microscope for distinguishing colonic neoplasia

    PubMed Central

    Liu, Jonathan T. C.; Mandella, Michael J.; Friedland, Shai; Soetikno, Roy; Crawford, James M.; Contag, Christopher H.; Kino, Gordon S.; Wang, Thomas D.

    2007-01-01

    A dual-axes confocal reflectance microscope has been developed that utilizes a narrowband laser at 1310 nm to achieve high axial resolution, image contrast, field of view, and tissue penetration for distinguishing among normal, hyperplastic, and dysplastic colonic mucosa ex vivo. Light is collected off-axis using a low numerical aperture objective to obtain vertical image sections, with 4- to 5-μm resolution, at tissue depths up to 610 μm. Post-objective scanning enables a large field of view (610 × 640 μm), and balanced-heterodyne detection provides sensitivity to collect vertical sections at one frame per second. System optics are optimized to effectively reject out-of-focus scattered light without use of a low-coherence gate. This design is scalable to millimeter dimensions, and the results demonstrate the potential for a miniature instrument to detect precancerous tissues, and hence to perform in vivo histopathology. PMID:17092168

  12. 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.

  13. Evaluation of an optical microscope method for coal-pyrite/marcasite differentiation

    SciTech Connect

    Sanner, Jr, W. S.; Meteney, D. L.

    1980-05-01

    A reflected-polarized light microscope technique for coal marcasite-pyrite differentiation is detailed. Presence of the two minerals was verified by x-ray diffraction analysis. The optical technique produced marcasite content values that were consistently lower than those measured by x-ray diffraction. Although the optical technique produces data that are at best semi-quantitative, it can be used to approximate (+-20%) marcasite concentration in coal without a heavy mineral concentration step.

  14. Differential force microscope for long time-scale biophysical measurements

    PubMed Central

    Choy, Jason L.; Parekh, Sapun H.; Chaudhuri, Ovijit; Liu, Allen P.; Bustamante, Carlos; Footer, Matthew J.; Theriot, Julie A.; Fletcher, Daniel A.

    2011-01-01

    Force microscopy techniques including optical trapping, magnetic tweezers, and atomic force microscopy (AFM) have facilitated quantification of forces and distances on the molecular scale. However, sensitivity and stability limitations have prevented the application of these techniques to biophysical systems that generate large forces over long times, such as actin filament networks. Growth of actin networks drives cellular shape change and generates nano-Newtons of force over time scales of minutes to hours, and consequently network growth properties have been difficult to study. Here, we present an AFM-based differential force microscope with integrated epifluorescence imaging in which two adjacent cantilevers on the same rigid support are used to provide increased measurement stability. We demonstrate 14 nm displacement control over measurement times of 3 hours and apply the instrument to quantify actin network growth in vitro under controlled loads. By measuring both network length and total network fluorescence simultaneously, we show that the average cross-sectional density of the growing network remains constant under static loads. The differential force microscope presented here provides a sensitive method for quantifying force and displacement with long time-scale stability that is useful for measurements of slow biophysical processes in whole cells or in reconstituted molecular systems in vitro. PMID:17477674

  15. LIGHT MICROSCOPICAL AND ELECTRON MICROSCOPICAL COMPARISONS OF NORMAL HEPATOCYTES OF WELL-DIFFERENTIATED HEPATOCELLULAR CARCINOMAS IN A TELEOST FISH

    EPA Science Inventory

    Well-differentiated hepatocellular carcinomas (HCC's) induced in the sheepshead minnow (Cyprinodon variagatus) with N-nitrosodiethylamine, permitted light microscopical and ultrastructural comparisons of normal hepatocytes and adjacent HCC cells. ormal hepatocytes contained typic...

  16. White light differential interference contrast microscope with a Sagnac interferometer.

    PubMed

    Chatterjee, Sanjib; Pavan Kumar, Y

    2014-01-10

    A new technique for producing a white light differential interference contrast (DIC) image using a lateral shearing, rotation phase shifting Sagnac interferometer (SI) is proposed. The SI, placed in the image space after the tube lens of a microscope system with spatially coherent white light Kohler illumination, splits the image forming beam into coherent components with small lateral shear. Phase shifts, between the interfering components, which can be considered as biased phase difference (BPD), are introduced by applying small angular rotation of the SI in its own plane. This variable BPD between the interfering white light components produces a uniform intensity colored background. The object related phase shift, due to the height difference between two close points on the object surface with separation on the order of least resolvable separation of the microscope objective, in addition to the BPD would produce a change in intensity/hue/color against a uniform background due to the BPD. Thus a DIC image is formed and the variable BPD provides an excellent means of improving the contrast of the image. PMID:24514064

  17. Multipoint fluorescence correlation spectroscopy with total internal reflection fluorescence microscope.

    PubMed

    Ohsugi, Yu; Kinjo, Masataka

    2009-01-01

    We report simultaneous determination of diffusion coefficients at different points of a cell membrane using a multipoint fluorescence correlation spectroscopy (FCS) system. A system carrying seven detection areas in the evanescent field is achieved by using seven optical fibers on the image plane in the detection port of an objective-type total internal reflection FCS (TIR-FCS) system. Fluctuation of fluorescence intensity is monitored and evaluated using seven photomultiplier tubes (PMTs) and a newly constructed multichannel correlator. We demonstrate simultaneous-multipoint FCS, with a 3-mus time resolution, to investigate heterogeneous structures such as cell membranes and membrane-binding molecular dynamics near glass surfaces in live cells. PMID:19256718

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

    PubMed Central

    Steiner, G.; Sidransky, D.

    1996-01-01

    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. PMID:8952515

  19. Microscopic structure of the Mach-type reflection of weak shock waves

    NASA Astrophysics Data System (ADS)

    Walenta, Z. A.

    The purpose of the present work was to investigate the microscopic structure of the three-shock inter-action region generated in a low-density shock tube during the Mach-type reflection of a weak shock wave. The experimental conditions corresponded to the case when Von Neumann's theory fails to predict the existence of reflection while Guderley's theory predicts the presence of a rarefaction wave behind the reflected shock. The experiment shows that under such conditions the Mach-type reflection does exist, and no rarefaction wave is present. A possible reason for this disagreement is the influence of viscosity, neglected in Von Neumann's and Guderley's theories.

  20. 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

  1. Combined reflection and transmission microscope for telemedicine applications in field settings.

    PubMed

    Biener, Gabriel; Greenbaum, Alon; Isikman, Serhan O; Lee, Kelvin; Tseng, Derek; Ozcan, Aydogan

    2011-08-21

    We demonstrate a field-portable upright and inverted microscope that can image specimens in both reflection and transmission modes. This compact and cost-effective dual-mode microscope weighs only ∼135 grams (<4.8 ounces) and utilizes a simple light emitting diode (LED) to illuminate the sample of interest using a beam-splitter cube that is positioned above the object plane. This LED illumination is then partially reflected from the sample to be collected by two lenses, creating a reflection image of the specimen onto an opto-electronic sensor-array that is positioned above the beam-splitter cube. In addition to this, the illumination beam is also partially transmitted through the same specimen, which then casts lensfree in-line holograms of the same objects onto a second opto-electronic sensor-array that is positioned underneath the beam-splitter cube. By rapid digital reconstruction of the acquired lensfree holograms, transmission images (both phase and amplitude) of the same specimen are also created. We tested the performance of this field-portable microscope by imaging various micro-particles, blood smears as well as a histopathology slide corresponding to skin tissue. Being compact, light-weight and cost-effective, this combined reflection and transmission microscope might especially be useful for telemedicine applications in resource limited settings. PMID:21709875

  2. Combined reflection and transmission microscope for telemedicine applications in field settings

    PubMed Central

    Biener, Gabriel; Greenbaum, Alon; Isikman, Serhan O.; Lee, Kelvin; Tseng, Derek; Ozcan, Aydogan

    2011-01-01

    We demonstrate a field-portable upright and inverted microscope that can image specimens in both reflection and transmission modes. This compact and cost-effective dual-mode microscope weighs only ~135 grams (<4.8 ounces) and utilizes a simple light emitting diode (LED) to illuminate the sample of interest using a beam-splitter cube that is positioned above the object plane. This LED illumination is then partially reflected from the sample to be collected by two lenses, creating a reflection image of the specimen onto an opto-electronic sensor-array that is positioned above the beam-splitter cube. In addition to this, the illumination beam is also partially transmitted through the same specimen, which then casts lensfree in-line holograms of the same objects onto a second opto-electronic sensor-array that is positioned underneath the beam-splitter cube. By rapid digital reconstruction of the acquired lensfree holograms, transmission images (both phase and amplitude) of the same specimen are also created. We tested the performance of this field-portable microscope by imaging various micro-particles, blood smears as well as a histopathology slide corresponding to skin tissue. Being compact, light-weight and cost-effective, this combined reflection and transmission microscope might especially be useful for telemedicine applications in resource limited settings. PMID:21709875

  3. Improved analysis of solar signals for differential reflectivity monitoring

    NASA Astrophysics Data System (ADS)

    Huuskonen, Asko; Kurri, Mikko; Holleman, Iwan

    2016-07-01

    The method for the daily monitoring of the differential reflectivity bias for polarimetric weather radars is developed further. Improved quality control is applied to the solar signals detected during the operational scanning of the radar, which efficiently removes rain and clutter-contaminated gates occurring in the solar hits. The simultaneous reflectivity data are used as a proxy to determine which data points are to be removed. A number of analysis methods to determine the differential reflectivity bias are compared, and methods based on surface fitting are found superior to simple averaging. A separate fit to the reflectivity of the horizontal and vertical polarization channels is recommended because of stability. Separate fitting also provides, in addition to the differential reflectivity bias, the pointing difference of the polarization channels. Data from the Finnish weather radar network show that the pointing difference is less than 0.02° and that the differential reflectivity bias is stable and determined to better than 0.04 dB. The results are compared to those from measurements at vertical incidence, which allows us to determine the total differential reflectivity bias including the differential receiver bias and the transmitter bias.

  4. Microscopic reflection difference spectroscopy for strain field of GaN induced by Berkovich nanoindentation

    NASA Astrophysics Data System (ADS)

    Gao, H. S.; Liu, Y.; Zhang, H. Y.; Wu, S. J.; Jiang, C. Y.; Yu, J. L.; Zhu, L. P.; Li, Y.; Huang, W.; Chen, Y. H.

    2014-02-01

    We have measured strain field of Berkovich nanoindentation by Raman mapping technique and microscopic reflection difference spectroscopy (μ-RDS). The validity of the μ-RDS method is verified by the accordance between the theoretical simulated result and the rotated measurement result. Comparing the two different methods, it is concluded that μ-RDS is sensitive and effective to measure anisotropic strain zone in the plane.

  5. 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…

  6. A two-reflection divergent differentiating critical angle refractometer

    NASA Astrophysics Data System (ADS)

    Guo, Wenping; Xia, Min; Li, Wei; Dai, Jie; Yang, Kecheng

    2011-05-01

    A new critical angle refractometer (CAR) for high accuracy refractive index measurement of liquid has been developed. The instrument improves the accuracy by two reflections in an elongated parallelogram prism, and acquires the angular reflectivity without any angle scanning parts through introduction of a point source with a divergent beam and a charge coupled device. In addition, it employs a simple and robust measurement method that gets the critical angle by differentiating the angular reflectivity. Through investigating absorbing media with absorption index κ (the imaginary part of refractive index) from 0 to 10-2.1, the theoretical calculation shows that the proposed two-reflection CAR would outperform the traditional one-reflection CAR on lowering the principal error from the differentiation method and improving the ability of getting the critical angle. By testing two typical liquids-salt-water solution and milk, the preliminary experiment indicates that this two-reflection divergent differentiating critical angle refractometer is feasible and of high accuracy.

  7. 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.

  8. 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.

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

    DOE PAGESBeta

    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

  10. 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).

  11. A correlative microscopical analysis of differentiating ovarian follicles of mammals.

    PubMed

    Anderson, E; Wilkinson, R F; Lee, G; Meller, S

    1978-06-01

    The mammalian ovary has been studied by optical microscopy and by scanning and transmission electron microscopy with the purpose of presenting an integrated view of the differentiating mammalian follicle. During follicular development, changes in the granulosa cells are particularly noteworthy and include dramatic modifications in cell shape coincident with antrum formation. The cytoplasmic processes of those granulosa cells immediately surrounding the oocyte, as well as the more peripheral granulosa cells comprising a second and third layer, traverse the zona pellucida, infrequently interdigitate with the microvilli of the egg, and make both desmosomal and gap junction contacts with the oocyte. The zona pellucida is thus distinguished by numerous fenestrations of varying diameters. The membrana limitans (basal lamina) is a bipartite structure composed of (a) a homogenous stratum upon which the peripheral layer of granulosa cells rests, and (b) an outer region of collagen-like fibers. The specific advantages and limitations of the different methodologies utilized to study folliculo-genesis are discussed. PMID:671553

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

    PubMed

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

    2015-08-01

    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). PMID:26267182

  13. 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

  14. 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.

  15. Differential reflective fiber-optic angular displacement sensor

    NASA Astrophysics Data System (ADS)

    Shan, Mingguang; Min, Rui; Zhong, Zhi; Wang, Ying; Zhang, Yabin

    2015-05-01

    Using the characteristic that the distance apart between the emitting fiber and receiving fiber only shifts the angular-power curve, a differential reflective fiber-optic sensor for angular displacement measurement is presented through subtraction of two power signals from two receiving fibers placed on both sides of one emitting fiber. A theoretical model is established to characterize the performance of the differential reflective fiber-optic angular displacement sensor. The measurements made indicate that the general behavior of the experimental results agrees with that of the theoretical results, and the sensor can improve sensitivity by about 120%, resulting in the significant improvement of anti-interference capability, which will be more suitable for high accuracy bipolar absolute angular displacement measurement. Design guidelines are also suggested to achieve desired sensor performances.

  16. 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. PMID:25611324

  17. A study of protein reactions with surface-bound molecular targets using oblique-incidence reflectivity difference microscope

    PubMed Central

    Landry, J. P.; Sun, Y. S.; Zhu, X. D.

    2009-01-01

    We applied oblique-incidence reflectivity difference (OI-RD) microscopes (a form of polarization-modulated nulling ellipsometry) to detection of biomolecular microarrays without external labeling in a study of protein reactions with surface-immobilized targets. We show that the optical reflectivity difference signals can be quantitatively related to changes in surface mass density of molecular layers as a result of the reactions. Our experimental results demonstrate the feasibility of using oblique-incidence reflectivity difference microscopes for high-throughput proteomics research such as screening unlabeled protein probes against libraries of surface-immobilized small-molecules. PMID:18566623

  18. An automatic detection software for differential reflection spectroscopy

    NASA Astrophysics Data System (ADS)

    Yuksel, Seniha Esen; Dubroca, Thierry; Hummel, Rolf E.; Gader, Paul D.

    2012-06-01

    Recent terrorist attacks have sprung a need for a large scale explosive detector. Our group has developed differential reflection spectroscopy which can detect explosive residue on surfaces such as parcel, cargo and luggage. In short, broad band ultra-violet and visible light is shone onto a material (such as a parcel) moving on a conveyor belt. Upon reflection off the surface, the light intensity is recorded with a spectrograph (spectrometer in combination with a CCD camera). This reflected light intensity is then subtracted and normalized with the next data point collected, resulting in differential reflection spectra in the 200-500 nm range. Explosives show spectral finger-prints at specific wavelengths, for example, the spectrum of 2,4,6, trinitrotoluene (TNT) shows an absorption edge at 420 nm. Additionally, we have developed an automated software which detects the characteristic features of explosives. One of the biggest challenges for the algorithm is to reach a practical limit of detection. In this study, we introduce our automatic detection software which is a combination of principal component analysis and support vector machines. Finally we present the sensitivity and selectivity response of our algorithm as a function of the amount of explosive detected on a given surface.

  19. Imaging microscopy by phase-contrast engine: retardation-modulated differential interference contrast microscope

    NASA Astrophysics Data System (ADS)

    Ishiwata, Hiroshi; Itoh, Masahide

    2014-11-01

    In the field of biology and medicine, observation object of the microscope has been changing from the thin specimen to the thick living tissue. Furthermore, observation of the internal structure of a living tissue is also desired by low invasion. However, the real structure of a phase object with three-dimensional distribution such as a living tissue is difficult to observe, because of the influence of the phase distribution before and behind of observation position. We enabled observation of the internal structure of living tissue without stain, by adding a new function to reduce the influence of phase distribution to our Retardation-Modulated differential interference contrast (RM-DIC) microscope system.

  20. Effect of differential spectral reflectance on DIAL measurements using topographic targets. [Differential Absorption Lidar

    NASA Technical Reports Server (NTRS)

    Grant, W. B.

    1982-01-01

    Differential absorption lidar (DIAL) measurements of atmospheric gases and temperature made using topographic targets to provide the backscattered signal are subject to errors from the differential spectral reflectance of the target materials. The magnitude of this effect is estimated for a number of DIAL measurements reported in the literature. Calculations are presented for several topographic targets. In general the effect on a DIAL measurement increases directly with increasing wavelength and laser line separation, and inversely with differential absorption coefficient and distance to the target. The effect can be minimized by using tunable or isotope lasers to reduce the laser line separation or by using additional reference wavelengths to determine the surface differential spectral reflectance.

  1. Microscopic Description of Intraband Absorption in Graphene: The Occurrence of Transient Negative Differential Transmission

    NASA Astrophysics Data System (ADS)

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

    2014-07-01

    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.

  2. Quantitative bloodstain analysis: differentiation of contact transfer patterns versus spatter patterns on fabric via microscopic inspection.

    PubMed

    Cho, Yuen; Springer, Faye; Tulleners, Frederic A; Ristenpart, William D

    2015-04-01

    In crime scene reconstruction, it is often necessary to differentiate "contact transfer" and "spatter" bloodstain patterns found on clothing. Current methodologies, however, are qualitative and prone to context bias. In this work, we demonstrate that microscopic inspection of the stain orientations provides a quantitative differentiation of bloodstains resulting from spatter versus contact transfer. Specifically, common knitted fabrics are comprised of parallel rows of left loop legs, in an upward diagonal orientation (/), and right loop legs in a downward diagonal orientation (\\). Our microscopic examination of more than 65,000 individual stained loop legs shows that spatter stains are approximately evenly distributed between left and right loop legs, but contact transfer stains are unevenly distributed: depending on the type of surface contacted, as many as 82% of the stains were preferentially located on the left loop legs. We further show that in these fabrics the left loop legs protrude further out than the right loop legs by approximately 50 μm, indicating that the observation of left loop legs preferentially stained over right loop legs is associated with the topography of the fabric. These findings suggest that microscopic quantification of the relative loop leg stain distributions could provide an objective means of differentiating contact transfer versus spatter patterns in crime scene reconstruction. PMID:25723999

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

    PubMed

    Niu, Yuanling; Burrage, Kevin; Chen, Luonan

    2016-05-01

    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. PMID:26920245

  4. Differentiation of individual human mesenchymal stem cells probed by FTIR microscopic imaging.

    PubMed

    Krafft, Christoph; Salzer, Reiner; Seitz, Sebastian; Ern, Christina; Schieker, Matthias

    2007-07-01

    Objective of this study is the novel application of Fourier transform infrared (FTIR) microscopic imaging to identify the differentiation state of individual human mesenchymal stem cells with or without osteogenic stimulation. IR spectra of several hundred single cells with lateral resolution of 5-10 microm were recorded using a FTIR imaging spectrometer coupled to a microscope with a focal plane array detector. A classification model based on linear discriminant analysis was trained to distinguish four cell types by their IR spectroscopic fingerprint. Without stimulation two cell types dominated, showing low or high levels of glycogen accumulation at the cell periphery. After stimulation, the protein composition in the cells changed and some cells started expressing calcium phosphate salts such as octacalciumphosphate, a precursor of the bone constituent hydroxyapatite. Few cells were identified which remained in their non-stimulated state. This study demonstrated for the first time that FTIR microscopic imaging can probe stem cell differentiation at the single cell level rapidly, non-destructively and with minimal preparation. PMID:17592583

  5. A Combined Light Sheet Fluorescence and Differential Interference Contrast Microscope for Live Imaging of Multicellular Specimens

    PubMed Central

    Baker, Ryan P.; Taormina, Michael J.; Jemielita, Matthew; Parthasarathy, Raghuveer

    2014-01-01

    We describe a microscope capable of both light sheet fluorescence microscopy (LSFM) and differential interference contrast microscopy (DICM). The two imaging modes, which to the best of our knowledge have not previously been combined, are complementary: LSFM provides three-dimensional imaging of fluorescently labeled components of multicellular systems with high speed, large fields of view, and low phototoxicity, while DICM reveals the unlabeled neighborhood of tissues, organs, and other structures with high contrast and inherent optical sectioning. Use of a single Nomarski prism for DICM 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 behavior of commensal microbes, immune cell motions, and more. PMID:25611324

  6. Standoff detection of explosive materials by differential reflection spectroscopy

    NASA Astrophysics Data System (ADS)

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

    2006-10-01

    It is shown that 2, 4, 6-Trinitrotoluene (TNT) displays strong and distinct structures in differential reflectograms, near 420 nm and 250 nm. These characteristic peaks are not observed from approximately two dozen organic and inorganic substances which we tested and which may be in or on a suitcase. This exclusivity infers an ideal technique for explosives detection in mass transit and similar locations. The described technique for detection of explosives is fast, inexpensive, reliable, portable, and is applicable from some distance, that is, it does not require contact with the surveyed substance. Moreover, we have developed a curve discrimination program for field applications of the technique. Other explosives such as 1, 3, 5-trinitro-1, 3, 5 triazacyclohexane (RDX), 1, 3, 5, 7-Tetranitro-1, 3, 5, 7- tetraazacyclooctane (HMX), 2, 4, 6, N-Tetranitro-N-methylaniline (Tetryl), Pentaerythritol tetranitrate (PETN), and nitroglycerin have also been investigated and demonstrate similar, but unique, characteristic spectra. The technique utilizes near-ultraviolet to visible light reflected from two spots on the same sample surface yielding a differential reflectogram corresponding to the absorption of the sample. The origin of the spectra is attributed to the highest occupied molecular orbital to lowest unoccupied molecular orbital (HOMO-LUMO) transitions of the respective explosive molecule. Experiments using transmission spectrophotometry have also been performed to compliment and confirm the specific transitions. The results are supported by computer modeling of the molecular orbitals that yield UV and visible transitions.

  7. 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

  8. Forensic Hair Differentiation Using Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy.

    PubMed

    Manheim, Jeremy; Doty, Kyle C; McLaughlin, Gregory; Lednev, Igor K

    2016-07-01

    Hair and fibers are common forms of trace evidence found at crime scenes. The current methodology of microscopic examination of potential hair evidence is absent of statistical measures of performance, and examiner results for identification can be subjective. Here, attenuated total reflection (ATR) Fourier transform-infrared (FT-IR) spectroscopy was used to analyze synthetic fibers and natural hairs of human, cat, and dog origin. Chemometric analysis was used to differentiate hair spectra from the three different species, and to predict unknown hairs to their proper species class, with a high degree of certainty. A species-specific partial least squares discriminant analysis (PLSDA) model was constructed to discriminate human hair from cat and dog hairs. This model was successful in distinguishing between the three classes and, more importantly, all human samples were correctly predicted as human. An external validation resulted in zero false positive and false negative assignments for the human class. From a forensic perspective, this technique would be complementary to microscopic hair examination, and in no way replace it. As such, this methodology is able to provide a statistical measure of confidence to the identification of a sample of human, cat, and dog hair, which was called for in the 2009 National Academy of Sciences report. More importantly, this approach is non-destructive, rapid, can provide reliable results, and requires no sample preparation, making it of ample importance to the field of forensic science. PMID:27412186

  9. 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

  10. 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.

  11. A Combined Light Sheet Fluorescence and Differential Interference Contrast Microscope for Live Imaging of Multicellular Specimens

    NASA Astrophysics Data System (ADS)

    Baker, Ryan; Taormina, Michael; Jemielita, Matthew; Parthasarathy, Raghuveer

    2015-03-01

    We present a microscope capable of both light sheet fluorescence microscopy (LSFM) and differential interference contrast microscopy (DICM). The two imaging modes, which to the best of our knowledge have not previously been combined, are complementary: LSFM provides high speed three-dimensional imaging of fluorescently labeled components of multicellular systems, large fields of view, and low phototoxicity, while DICM reveals the unlabeled neighborhood of tissues, organs, and other structures with high contrast and inherent optical sectioning. Use of a shared detection path for both imaging modes enables simple integration of the two techniques in one microscope. To demonstrate the instrument's utility, we provide several examples which focus on the digestive tract of the larval zebrafish. We show that DICM can sometimes circumvent the need for fluorescent based techniques, augmenting the number of parameters obtainable per experiment when used alongside LSFM, and that DICM can be used to augment each experiment by imaging complementary features, such as non-fluorescent local environments near fluorescent samples (e.g. fluorescent enteric neurons imaged alongside the non-fluorescent gut wall), interactions between fluorescent and non-fluorescent samples (e.g. bacteria), and more. NSF Award 0922951, NIH Award 1P50 GM098911

  12. [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. PMID:26415453

  13. 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.

  14. Fecal calprotectin: a marker for clinical differentiation of microscopic colitis and irritable bowel syndrome

    PubMed Central

    von Arnim, Ulrike; Wex, Thomas; Ganzert, Christine; Schulz, Christian; Malfertheiner, Peter

    2016-01-01

    Background The aim of this study is to compare two methods for measuring fecal calprotectin (FC) concentration and to evaluate the possibility of differentiation between microscopic colitis (MC) and irritable bowel syndrome (IBS). Methods Twenty-three patients with MC (six patients with active disease and 17 patients retested in remission) and 20 patients with IBS were prospectively included in this study. Active disease state of MC was determined by clinical symptoms of >3 bowel movements per day and histological correlate. All patients underwent ileocolonoscopy, including segmental biopsy samples for histology. FC levels in stool samples were analyzed using a rapid test system (Quantum Blue®) and an enzyme-linked immunosorbent assay (ELISA). Results FC levels were significantly higher in patients with active MC (median 48 μg/g [23–106]) compared to patients with IBS (median 2 μg/g [1–111.83]), P=0.0001 using an ELISA. FC level of patients with MC in remission was 22 μg/g (1–106.4), which is similar to those identified in patients with IBS. The difference of FC levels between active MC and IBS was not detected by the FC rapid test (P=0.635). Discussion FC levels might serve as parameter for differentiation between patients with active MC and IBS. Since there is no surrogate marker available at present for MC, FC appears to be a candidate for differentiating MC from IBS. Conclusion High FC levels, which were analyzed by ELISA, are a potential marker for patients with active MC compared to those with IBS. The FC rapid test was less suitable for this purpose. PMID:27147826

  15. Charge radii in macroscopic-microscopic mass models of reflection asymmetry

    SciTech Connect

    Iimura, H.; Buchinger, F.

    2008-12-15

    We show that the charge radii of reflection-asymmetric nuclei calculated in the frame of the finite-range droplet model are in better agreement with measured charge radii when reflection asymmetry is taken into account. However discrepancies between experimental and calculated changes in mean square charge radii still remain for some isotopic chains. These discrepancies cannot be removed by empirically including dynamic contributions to the quadrupole deformation.

  16. 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.

  17. Study on the Reflection Coefficient of Clay from the View Points of the Microscopic Structure and the Mineralogy

    NASA Astrophysics Data System (ADS)

    Miyoshi, S.; Tokunaga, T.; Mogi, K.

    2011-12-01

    Many studies have shown that abnormally high pore pressure can be generated by the act of clay as semipermeable membrane. The reason is that surface electricity of smectite composing of clay generates the electric double layer in clay pores that ristricts the migration of ions. The act of clay as semipermeable membrane has not been understood quantitatively from the view points of the microscopic structure and the mineral compositions of clay. The authors have developed a laboratory apparatus and a numerical simulator to obtain the fundamental data for the quantitative understanding of the phenomena. In this study, the samples of a tarbidite and a clay of Niigata sedimentary basin were collected. The analysis of the microscopic structure and the mineralogy and the laboratory experiments to measure the reflection coefficient were done. The large part of pore radius of clay is less than 1.0μm while the pore radius of approximately 35% of the pore volume of tarbidite is more than 1.0μm. The XRD chart of the tarbidite does not show the peek of smectite while that of the clay shows it. Based on the data that the authors have obtained so far, it is suggested that there is a relationship between the reflection coefficient and the methylene blue adsorption of clay.

  18. Improvements to a Grating-Based Spectral Imaging Microscope and Its Application to Reflectance Analysis of Blue Pen Inks.

    PubMed

    McMillan, Leilani C; Miller, Kathleen P; Webb, Michael R

    2015-08-01

    A modified design of a chromatically resolved optical microscope (CROMoscope), a grating-based spectral imaging microscope, is described. By altering the geometry and adding a beam splitter, a twisting aberration that was present in the first version of the CROMoscope has been removed. Wavelength adjustment has been automated to decrease analysis time. Performance of the new design in transmission-absorption spectroscopy has been evaluated and found to be generally similar to the performance of the previous design. Spectral bandpass was found to be dependent on the sizes of apertures, and the smallest measured spectral bandpass was 1.8 nm with 1.0 mm diameter apertures. Wavelength was found to be very linear with the sine of the grating angle (R(2) = 0.9999995), and wavelength repeatability was found to be much better than the spectral bandpass. Reflectance spectral imaging with a CROMoscope is reported for the first time, and this reflectance spectral imaging was applied to blue ink samples on white paper. As a proof of concept, linear discriminant analysis was used to classify the inks by brand. In a leave-one-out cross-validation, 97.6% of samples were correctly classified. PMID:26162719

  19. 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.

  20. Measurement of anchoring coefficient of homeotropically aligned nematic liquid crystal using a polarizing optical microscope in reflective mode

    NASA Astrophysics Data System (ADS)

    Baek, Sang-In; Kim, Sung-Jo; Kim, Jong-Hyun

    2015-09-01

    Although the homeotropic alignment of liquid crystals is widely used in LCD TVs, no easy method exists to measure its anchoring coefficient. In this study, we propose an easy and convenient measurement technique in which a polarizing optical microscope is used in the reflective mode with an objective lens having a low depth of focus. All measurements focus on the reflection of light near the interface between the liquid crystal and alignment layer. The change in the reflected light is measured by applying an electric field. We model the response of the director of the liquid crystal to the electric field and, thus, the change in reflectance. By adjusting the extrapolation length in the calculation, we match the experimental and calculated results and obtain the anchoring coefficient. In our experiment, the extrapolation lengths were 0.31 ± 0.04 μm, 0.32 ± 0.08 μm, and 0.23 ± 0.05 μm for lecithin, AL-64168, and SE-5662, respectively.

  1. 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.

  2. 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

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

    PubMed

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

    2015-11-01

    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

  4. 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.

  5. Label-free imaging of intracellular motility by low-coherent quantitative phase microscope in reflection geometry

    NASA Astrophysics Data System (ADS)

    Yamauchi, Toyohiko; Iwai, Hidenao; Yamashita, Yutaka

    2011-11-01

    We demonstrate tomographic imaging of intracellular activity of living cells by a low-coherent quantitative phase microscope. The intracellular organelles, such as the nucleus, nucleolus, and mitochondria, are moving around inside living cells, driven by the cellular physiological activity. In order to visualize the intracellular motility in a label-free manner we have developed a reflection-type quantitative phase microscope which employs the phase shifting interferometric technique with a low-coherent light source. The phase shifting interferometry enables us to quantitatively measure the intensity and phase of the optical field, and the low-coherence interferometry makes it possible to selectively probe a specific sectioning plane in the cell volume. The results quantitatively revealed the depth-resolved fluctuations of intracellular surfaces so that the plasma membrane and the membranes of intracellular organelles were independently measured. The transversal and the vertical spatial resolutions were 0.56 μm and 0.93 μm, respectively, and the mechanical sensitivity of the phase measurement was 1.2 nanometers. The mean-squared displacement was applied as a statistical tool to analyze the temporal fluctuation of the intracellular organelles. To the best of our knowledge, our system visualized depth-resolved intracellular organelles motion for the first time in sub-micrometer resolution without contrast agents.

  6. Melanocytic nevi with special features: clinical-dermoscopic and reflectance confocal microscopic-findings.

    PubMed

    Larre Borges, A; Zalaudek, I; Longo, C; Dufrechou, L; Argenziano, G; Lallas, A; Piana, S; Moscarella, E

    2014-07-01

    Histopathology is considered the 'gold' standard for the diagnosis and classification of melanocytic nevi, but the widespread use of in vivo diagnostic technologies such as dermoscopy and reflectance confocal microscopy (RCM), has enriched profoundly the knowledge regarding the morphological variability in nevi. This is because most morphological observations made via these in vivo tools are closely correlated with features seen in histopathology. Dermoscopy has allowed for a more detailed classification of nevi. As such, dermoscopy identifies four main morphologic groups (i.e. globular, reticular, starburst and structureless blue nevi), one group of nevi located at special body sites (i.e. face, acral, nail) and one group of nevi with special features. This latter category consists of nevi of the former categories, which are typified by peculiar clinical-histopathological findings. They can be subdivided into 'melanoma simulators' including combined nevi, recurrent nevi and sclerosing nevus with pseudomelanomatous features, 'targetoid' nevi (i.e. halo, cockade, irritated targetoid haemosiderotic and eczematous nevus) and uncommon histopathological variants such as desmoplastic, white dysplastic or ballon cell nevus. While the dermoscopic and RCM patterns of the former categories have been studied in detail, little is currently known about the clinical morphology of the heterogeneous group of 'special' nevi. In this article, we describe the clinical, dermoscopic and RCM features of 'special' nevi and review the current literature on this group of melanocytic proliferations. PMID:24171788

  7. 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. PMID:26280279

  8. 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

  9. Analysis of the accuracy of the inverse problem solution for a differential heterodyne microscope as applied to rectangular plasmonic waveguides

    NASA Astrophysics Data System (ADS)

    Akhmedzhanov, I. M.; Baranov, D. V.; Zolotov, E. M.

    2016-06-01

    The existence, uniqueness, and stability of the inverse problem solution for a scanning differential heterodyne microscope as applied to rectangular plasmonic waveguides have been analyzed. The consideration is based on an algorithm using a trial-and-error method that we proposed previously to characterize plasmonic waveguides with a triangular profile. The error of the inverse problem (IP) solution is calculated as dependent on the initial data and with allowance for their errors. Instability domains are found for the IP solution, where the solution error sharply increases. It is shown that the instability domains can be eliminated and the accuracy of the IP solution can be significantly improved in the entire range of initial data by taking initial data in the form of two phase responses of the microscope at different wavelengths.

  10. Oblique-incidence reflectivity difference microscope for label-free high-throughput detection of biochemical reactions in a microarray format

    NASA Astrophysics Data System (ADS)

    Zhu, Xiangdong; Landry, James P.; Sun, Yung-Shin; Gregg, Jeff P.; Lam, Kit S.; Guo, Xiaowen

    2007-04-01

    We describe a recently developed oblique-incidence reflectivity difference (OI-RD) microscope, a form of polarization-modulated imaging ellipsometer, for label-free-high-throughput detection of biomolecular reactions on DNA and protein microarrays. We present examples of application of this technique to end-point and real-time investigations of DNA-DNA hybridization, antibody-antigen capture, and protein-small-molecule binding reactions. Compared to a conventional imaging ellipsometer based on the polarizer-compensator-sample-analyzer scheme and under the off-null condition, a polarization-modulated OI-RD microscope is inherently more sensitive by at least 1 order of magnitude to thickness changes on a solid surface. Compared with imaging surface plasmon resonance microscopes based on reflectance change on falling or rising slopes of the surface plasmon resonance, the OI-RD microscope (1) has a comparable sensitivity, (2) is applicable to conventional microscope glass slides, and (3) easily covers a field of view as large as the entire surface of a 1 in.×3 in. (2.54 cm×7.62 cm) microscope slide.

  11. 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.

  12. Self-reflection across time: cortical midline structures differentiate between present and past selves

    PubMed Central

    Feyers, Dorothée; Majerus, Steve; Collette, Fabienne; Van der Linden, Martial; Maquet, Pierre; Salmon, Eric

    2008-01-01

    The processing of personal changes across time and the ability to differentiate between representations of present and past selves are crucial for developing a mature sense of identity. In this study, we explored the neural correlates of self-reflection across time using functional magnetic resonance imaging (fMRI). College undergraduates were asked to reflect on their own psychological characteristics and those of an intimate other, for both the present time period (i.e. at college) and a past time period (i.e. high school years) that involved significant personal changes. Cortical midline structures (CMS) were commonly recruited by the four reflective tasks (reflecting on the present self, past self, present other and past other), relative to a control condition (making valence judgments). More importantly, however, the degree of activity in CMS also varied significantly according to the target of reflection, with the ventral and dorsal medial prefrontal cortex and the posterior cingulate cortex being more recruited when reflecting on the present self than when reflecting on the past self or when reflecting on the other person. These findings suggest that CMS may contribute to differentiate between representations of present and past selves. PMID:19015116

  13. Development of new apertureless near-field scanning optical microscope tip using finite-differential time-domain calculation

    NASA Astrophysics Data System (ADS)

    Kodama, Takashi; Ohtani, Hiroyuki

    2006-12-01

    We calculated the electric field enhancement factor of the apertureless near-field scanning optical microscope (ANSOM) tip using the finite-differential time-domain method. The results revealed that the enhancement factor of the silver tip remarkably decreased as the rounded tip radius increased. On the other hand, aggregated silver nanoparticles resulted in a strong field enhancement. Therefore, we developed a silver nanoparticles immobilized tip for the ANSOM probe and attempted to measure the surface enhanced Raman scattering spectrum of carbon onion molecules using it. We successfully detected the Raman spectra of individual carbon onions with a high sensitivity.

  14. Polarization-dependent differential reflectance spectroscopy for real-time monitoring of organic thin film growth.

    PubMed

    Navarro-Quezada, A; Aiglinger, M; Ghanbari, E; Wagner, Th; Zeppenfeld, P

    2015-11-01

    By monitoring the reflectance of a sample surface during deposition of a thin organic film, one can obtain information with submonolayer resolution in real-time. A special kind of optical spectroscopy is Differential Reflectance Spectroscopy (DRS), which compares the reflectance before and during deposition of a thin film or any other change of the surface optical properties. In this work, we present an extended DRS setup that allows monitoring simultaneously both linear polarization states (s and p) of the reflected light. We implement polarization-dependent DRS to monitor the growth of perflouropentacene thin films on a Ag(110) single crystal. The setup allows us to deduce the optical anisotropy of the sample and, in particular, the preferred orientation of the molecules on the surface. PMID:26628122

  15. Differential internal multi-reflection method for nano-displacement measurement

    NASA Astrophysics Data System (ADS)

    Ku, Yulong; Kuang, Cuifang; Luo, Ding; Wang, Tingting; Li, Haifeng

    2012-10-01

    By utilizing the internal-reflection effect at air-glass boundary, we have proposed a novel method of nano-displacement measurement. Excellent linearity of the reflectance versus the angle of incidence in internal reflection is achieved by making use of a differential detection scheme. Thereby, the target's displacement which causes the change of incident angle can be determined accurately by measuring reflectance. Using a differential detector such as quadrant detector, a compact system based on the above method has been developed, with advantages of simple configuration and low costs compared with interferometers and traditional confocal methods (CMs). The resolution of this system is about 2 nm in a wide measurement range. Factors such as the initial angle of incidence, the number of reflections, and the polarization state of the light determine the resolution and measurement range. It is very suitable for many potential applications, especially in the automatic focus of the state-of-art microscopy, in which the traditional problem of focus drift may be solved. In addition, theoretical analysis and experimental results of a prototype sensor are presented.

  16. Influence of spatial differential reflection parameters on 2,4,6- trinitrotoluene (TNT) absorption spectra

    NASA Astrophysics Data System (ADS)

    Dubroca, Thierry; Guetard, Ga"l.; Hummel, Rolf E.

    2012-06-01

    Differential reflectometry has been shown to be a sensitive and fast tool to detect explosive substances on surfaces such as luggage and parcel. This paper elucidates the influence of several parameters on the sensitivity of the technique. An expression for the reflected intensity that contains the influence of angle of incidence, wavelength of the incident light, and surface roughness has been established. The feature used to identify and detect TNT stems mainly from the diffuse component of the reflected light. This spectral "finger-print" shape does not change by varying these parameters. The maximum sensitivity is obtained for samples which are strongly diffusive and weakly specular.

  17. Differential Phase-Contrast Scanning X-Ray Microscope For Observation Of Low-Z element Specimen

    SciTech Connect

    Takeuchi, Akihisa; Uesugi, Kentaro; Suzuki, Yoshio

    2010-07-23

    Differential phase-contrast scanning x-ray microscope/microtomography have been developed. A fast readout charge-coupled device (CCD) camera coupled with a visible-light conversion unit is used as a detector to record the transmitted intensity distribution of far-field image for every pixel in a scan. Simultaneous absorption and phase-contrast images are given from a single scan by image-processing of the CCD frames. The system is constructed at BL20XU of SPring-8, and its feasibility is demonstrated at the photon energy of 8 keV. A tantalum test chart is observed and its finest structure of 140 nm pitch pattern is clearly observed. Measured phase sensitivity is approximately {lambda}/270. Some low-Z element specimens are observed and obtained phase contrast image shows much higher sensitivity than that of absorption contrast.

  18. 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.

  19. Laser multi-reflection differential confocal long focal-length measurement.

    PubMed

    Li, Zhigang; Qiu, Lirong; Zhao, Weiqian; Zhao, Qi

    2016-06-20

    We propose a new laser multi-reflection differential confocal focal-length measurement (LDCFM) method to meet the requirements of high-precision measurements of long focal lengths. An optical flat and a reflector are placed behind a test lens for reflecting the measuring beam repeatedly. Then, LDCFM uses the property that the null points of differential confocal response curves precisely correspond to the convergence points of the multi-reflected measuring beam to exactly determine the positions of the convergence points accurately. Subsequently, the position variation of the reflector is measured with different reflection times by using a distance-measuring instrument, and thereby the long focal length is measured precisely. Theoretical analyses and preliminary experimental results indicate that the LDCFM method has a relative expanded standard uncertainty (k=2) of 0.04% for the test lens with a focal length of 9.76 m. The LDCFM method can provide a novel approach for high-precision focal-length measurements. PMID:27409117

  20. Transformation of thylakoid membranes during differentiation from vegetative cell into heterocyst visualized by microscopic spectral imaging.

    PubMed

    Kumazaki, Shigeichi; Akari, Masashi; Hasegawa, Makoto

    2013-03-01

    Some filamentous cyanobacteria carry out oxygenic photosynthesis in vegetative cells and nitrogen fixation in specialized cells known as heterocysts. Thylakoid membranes in vegetative cells contain photosystem I (PSI) and PSII, while those in heterocysts contain predominantly PSI. Therefore, the thylakoid membranes change drastically when differentiating from a vegetative cell into a heterocyst. The dynamics of these changes have not been sufficiently characterized in situ. Here, we used time-lapse fluorescence microspectroscopy to analyze cells of Anabaena variabilis under nitrogen deprivation at approximately 295 K. PSII degraded simultaneously with allophycocyanin, which forms the core of the light-harvesting phycobilisome. The other phycobilisome subunits that absorbed shorter wavelengths persisted for a few tens of hours in the heterocysts. The whole-thylakoid average concentration of PSI was similar in heterocysts and nearby vegetative cells. PSI was best quantified by selective excitation at a physiological temperature (approximately 295 K) under 785-nm continuous-wave laser irradiation, and detection of higher energy shifted fluorescence around 730 nm. Polar distribution of thylakoid membranes in the heterocyst was confirmed by PSI-rich fluorescence imaging. The findings and methodology used in this work increased our understanding of how photosynthetic molecular machinery is transformed to adapt to different nutrient environments and provided details of the energetic requirements for diazotrophic growth. PMID:23274239

  1. 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

  2. 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

  3. 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.

  4. 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. PMID:23733020

  5. 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.

  6. Top Differential Diagnosis Should Be Microscopic Polyangiitis in ANCA-Positive Patient with Diffuse Pulmonary Hemorrhage and Hemosiderosis.

    PubMed

    Ward, Nicholas D; Cosner, Diane E; Lamb, Colleen A; Li, Wei; Macknis, Jacqueline K; Rooney, Michele T; Zhang, Ping L

    2014-01-01

    A rat model of antineutrophil cytoplasmic antibody (ANCA) associated vasculitides reveals crescentic glomerulonephritis as seen in human renal biopsies and diffuse lung hemorrhage that is not well documented in human lung biopsies. A 64-year-old male, with shortness of breath and mild elevation of serum creatinine, was found to have a positive serum test for ANCA, but negative antiglomerular basement membrane antibody. A renal biopsy showed pauci-immune type of crescentic glomerulonephritis and focal arteritis. The prior lung wedge biopsy was retrospectively reviewed to show diffuse hemorrhage and hemosiderosis with focal giant cells. In addition, small arteries revealed subtle neutrophil aggregation, and margination along vascular endothelium, but no definitive vasculitis. The pathology of ANCA associated vasculitides results from activated neutrophils by ANCA and subsequent activation of the alternative complement cascade with endothelial injury, neutrophil aggregation and margination. Our findings, after the correlation between lung biopsy and renal biopsy, imply that the top differential diagnosis in the lung biopsy should be microscopic polyangiitis when diffuse pulmonary hemorrhage and hemosiderosis are present in this ANCA-positive patient. PMID:25525543

  7. Analysis of beam interference reflected from atomic force microscope tip and periodic silicon surface under various humidity conditions

    NASA Astrophysics Data System (ADS)

    Banerjee, Hans P.; Weerasinghe, Asanka T.; Lyuksyutov, Sergei F.

    2012-10-01

    Dynamical sensing based on combination of classical optical effects and atomic force microscopy (AFM) presents challenge for analysis of the forces at the nanoscale and beyond. An interference effect between light reflected from an AFM cantilever and highly reflective silicon surface of the calibration grating was studied for relative humidity (RH) varied between 9 and 60%. Force-distance analysis indicates on separation of capillary, van der Waals, adhesion, and electrostatic forces. The measurements performed in contact AFM mode suggest that the period of interference pattern observed in displacement curves is a function of humidity and varies between 293 nm at RH = 9% and 335 nm at RH > 50% with standard deviation less than 8 nm. Clear change of the interference period suggests that other than hardwarerelated factors may be involved in the formation of the interference in force-distance curves.

  8. 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

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

    PubMed

    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

  10. 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

  11. 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.

  12. 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. PMID:26977363

  13. Maternal reflective functioning as a multidimensional construct: Differential associations with children's temperament and externalizing behavior.

    PubMed

    Smaling, H J A; Huijbregts, S C J; van der Heijden, K B; van Goozen, S H M; Swaab, H

    2016-08-01

    Maternal reflective functioning (RF) has been associated with children's behavioral development. This study examined maternal prenatal and postnatal RF, as measured by the Pregnancy Interview and Parent Development Interview, as multidimensional constructs. It was also examined whether the RF-dimensions were associated with children's temperament and externalizing behavior, as assessed by several questionnaires. The sample consisted of 123 first-time mothers (M age=22.85years, SD=2.21) and their children (M age=19.97months, SD=0.85, 56% male). Two related but distinct dimensions were found for prenatal RF, termed self-focused and child-focused mentalization. Three dimensions were observed for postnatal RF, termed self-focused, child-focused, and relation-focused mentalization. Results showed that prenatal RF negatively related to reported child physical aggression. Postnatal self-focused RF was positively linked to externalizing behavior and negative emotionality in offspring, while relation-focused RF scores were negatively associated with child physical aggression. Findings show that it is important to also look at the specific RF-dimensions when examining the effects of maternal RF on children's behavioral development, as differential associations with behavioral outcomes exist. Discussion further focuses on the importance of these findings in prevention and clinical practice, and suggestions are being made to further improve the measurement of maternal RF-dimensions. PMID:27522031

  14. Using liquid crystal variable retarders for fast modulation of bias and shear direction in quantitative differential interference contrast (DIC) microscope

    PubMed Central

    Shribak, Michael

    2016-01-01

    Conventional DIC microscope shows the two-dimensional distribution of optical path length gradient encountered along the shear direction between two interfering beams. It is therefore necessary to rotate unknown objects in order to examine them at several orientations. We built new DIC beam shearing assembly, which allows the bias to be modulated and shear directions to be switched rapidly without any mechanically rotating the specimen or the prisms. The assembly consists of two standard DIC prisms with liquid crystal cell in between. Another liquid crystal cell is employed for modulating a bias. All components do not require a special design and are available on the market. We describe techniques for measuring parameters of DIC prisms and calibrating liquid crystal cells. One beam-shearing assembly is added to the illumination path and another one to the imaging path of standard microscope. Two sets of raw DIC images at the orthogonal shear directions and two or three different biases are captured and processed within a second. Then the quantitative image of optical path gradient distribution within a thin optical section is displayed on a computer screen. The obtained data are also used to compute the quantitative distribution of optical phase, which represents refractive index gradient or height distribution. It is possible to generate back the enhanced regular DIC images with any desired shear direction. New DIC microscope can be combined with other techniques, such as fluorescence and polarization microscopy.

  15. 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.

  16. 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.

  17. 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.

  18. Wave optics simulation of atmospheric turbulence and reflective speckle effects in CO2 differential absorption lidar (DIAL)

    NASA Astrophysics Data System (ADS)

    Nelson, Douglas H.; Petrin, Roger R.; MacKerrow, Edward P.; Schmitt, Mark J.; Quick, Charles R., Jr.; Zardecki, Andrew; Porch, William M.; Whitehead, Michael C.; Walters, Donald L.

    1998-09-01

    The measurement sensitivity of CO2 differential absorption LIDAR (DIAL) can be affected by a number of different processes. We will 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 CO2 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.

  19. 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.

  20. In vivo soft tissue differentiation by diffuse reflectance spectroscopy: preliminary results

    NASA Astrophysics Data System (ADS)

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

    Remote laser surgery does not provide haptic feedback to operate layer by layer and preserve vulnerable anatomical structures like nerve tissue or blood vessels. The aim of this study is identification of soft tissue in vivo by diffuse reflectance spectroscopy to set the base for a feedback control system to enhance nerve preservation in oral and maxillofacial laser surgery. Various soft tissues can be identified by diffuse reflectance spectroscopy in vivo. The results may set the base for a feedback system to prevent nerve damage during oral and maxillofacial laser surgery.

  1. 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…

  2. TETRACHLORODIBENZODIOXIN ISOMER DIFFERENTIATION BY MICRO DIFFUSE REFLECTANCE FOURIER TRANSFORM INFRARED SPECTROMETRY AT THE LOW NANOGRAM LEVEL

    EPA Science Inventory

    Infrared diffuse reflectance spectra were recorded for the 22 tetrachlorodibenzodioxin isomers (TCDDs). By use of micro-DRIFT techniques and signal averaging, identifiable spectra for each of the isomers were achieved at low nanogram levels. Spectral features in the 1200/cm to 16...

  3. 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.

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

    PubMed

    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. PMID:26590218

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  6. 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.

  7. 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.

  8. Transformation of Thylakoid Membranes during Differentiation from Vegetative Cell into Heterocyst Visualized by Microscopic Spectral Imaging1[W

    PubMed Central

    Kumazaki, Shigeichi; Akari, Masashi; Hasegawa, Makoto

    2013-01-01

    Some filamentous cyanobacteria carry out oxygenic photosynthesis in vegetative cells and nitrogen fixation in specialized cells known as heterocysts. Thylakoid membranes in vegetative cells contain photosystem I (PSI) and PSII, while those in heterocysts contain predominantly PSI. Therefore, the thylakoid membranes change drastically when differentiating from a vegetative cell into a heterocyst. The dynamics of these changes have not been sufficiently characterized in situ. Here, we used time-lapse fluorescence microspectroscopy to analyze cells of Anabaena variabilis under nitrogen deprivation at approximately 295 K. PSII degraded simultaneously with allophycocyanin, which forms the core of the light-harvesting phycobilisome. The other phycobilisome subunits that absorbed shorter wavelengths persisted for a few tens of hours in the heterocysts. The whole-thylakoid average concentration of PSI was similar in heterocysts and nearby vegetative cells. PSI was best quantified by selective excitation at a physiological temperature (approximately 295 K) under 785-nm continuous-wave laser irradiation, and detection of higher energy shifted fluorescence around 730 nm. Polar distribution of thylakoid membranes in the heterocyst was confirmed by PSI-rich fluorescence imaging. The findings and methodology used in this work increased our understanding of how photosynthetic molecular machinery is transformed to adapt to different nutrient environments and provided details of the energetic requirements for diazotrophic growth. PMID:23274239

  9. Microscopic and biochemical evidence of differentially virulent field isolates of Diplocarpon rosae causing black spot disease of roses.

    PubMed

    Gachomo, Emma W; Kotchoni, Simeon O

    2010-01-01

    Black spot disease caused by Diplocarpon rosae is one of the most widespread diseases of roses that are very difficult to control due to the generative reproduction and complex genetic constitution of roses and up to now the control of black spot still requires intensive use of systemic fungicides. Here we report for the first time evidence of differentially virulent field isolates of D. rosae. Using a combination of fungal structures, disease symptoms and host cells protein expression pattern analysis we here provide direct biochemical evidence that tropical field isolates of D. rosae are more virulent and caused disease symptoms earlier than their temperate counterparts. The tropical fungal field isolates strongly induced an excessive accumulation of ROS and repressed activity of pathogenesis-related proteins such as peroxidases, chitinase and phenylalanine ammonia lyase compared to their temperate counterparts. These findings bring insights into a hidden pathogenic characteristic of tropical D. rosae field isolates compared to their temperate counterparts and open a novel dimension of parameters to be considered when controlling black spot disease of roses by fungicides in tropical versus temperate regions. Interestingly, we found that treatment of rose leaves with ROS (H2O2) prior to fungal inoculation promoted plant defense response regardless of the isolate virulence based on protein expression pattern analysis, suggesting that ROS (H2O2) can be efficiently incorporated into black spot disease management. PMID:20137960

  10. 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.

  11. 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.

  12. Remote sensing of propane and methane by means of a differential absorption lidar by topographic reflection

    NASA Astrophysics Data System (ADS)

    Prasad, Narasimha S.; Geiger, Allen R.

    1996-04-01

    The development of a differential absorption lidar (DIAL) system in the mid-IR region for the detection and monitoring of light hydrocarbons is presented. Two lithium niobate optical parametric oscillators provided the signal and reference wavelengths. With the aid of a retroreflector, the system detected 0.63 ppm of propane and 0.05 ppm of methane in the atmosphere at a greater than 1 mile range in the controlled release tests. Subsequently, the system mapped a petroleum deposit in eastern New Mexico.

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

    PubMed

    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

  14. 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

  15. Does Late Miocene Exhumation Along the Western Slope of the Colorado Rockies Reflect Differential Rock Uplift?

    NASA Astrophysics Data System (ADS)

    Rosenberg, R. H.; Kirby, E.; Aslan, A.; Karlstrom, K. E.; Heizler, M. T.; Kelley, S. A.; Piotraschke, R. E.; Furlong, K. P.

    2011-12-01

    of the Rockies. Additionally, new cosmogenic burial ages from fan-terrace complexes near Rifle, Colorado show that Colorado River incision occurred at similar rates over both 10 Ma and 2 Ma timescales. Fluvial incision in response to relative base level fall or to changes in regional climate cannot easily explain the history of differential incision along the western slope. Given the correspondence of steep channels, large magnitude incision and regions of low seismic velocity mantle, we suggest that differential rock uplift, driven, in part, by differences in the buoyancy and/or convective flow of the mantle beneath western Colorado is the likely driver for Neogene incision.

  16. Microscopic colitis.

    PubMed

    Pardi, Darrell S

    2014-02-01

    Microscopic colitis is a frequent cause of chronic watery diarrhea, especially in older persons. Common associated symptoms include abdominal pain, arthralgias, and weight loss. The incidence of microscopic colitis had been increasing, although more recent studies have shown a stabilization of incidence rates. The diagnosis is based on characteristic histologic findings in a patient with diarrhea. Microscopic colitis can occur at any age, including in children, but it is primarily seen in the elderly. Several treatment options exist to treat the symptoms of microscopic colitis, although only budesonide has been well studied in randomized clinical trials. PMID:24267602

  17. 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.

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

    PubMed

    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

  19. 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

  20. 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. PMID:26874961

  1. Formation of micro-domains as functional regions in biomembranes: specific interactions inferred by differential scanning calorimetry and microscopic imaging of membrane fluidity

    NASA Astrophysics Data System (ADS)

    Ohki, Kazuo

    2005-08-01

    Using differential scanning calorimetry, preferential interaction between melittin and dimyristoylphosphatidylcholine was observed in various binary mixtures of phospholipids. It is shown that matching of the hydrophobic regions between melittin and fatty acyl chains of phospholipids is the most important factor. Using a microscopic imaging instrument for membrane fluidity, specific interaction between cholesterol and sphingomyelin in rafts was confirmed in living CHO cells. An environment sensitive fluorescence dye, laurdan, was used in this home-built instrument. The membrane fluidity of the cells was scarcely affected with the treatment of sphingomyelinase up to 0.1 U ml-1. On the other hand, increase of the membrane fluidity was observed in CHO cells treated with methyl-beta-cyclodextrin, which removes cholesterol molecules from biomembranes of the cells in a concentration dependent manner up to 10 mM. But a low concentration of methyl-beta-cyclodextrin (1 mM) did not raise the membrane fluidity. However, increase of membrane fluidity was observed in CHO cells treated with sphingomyelinase and then with 1 mM methyl-beta-cyclodextrin. These results suggest specific interaction between sphingomyelin and cholesterol in the rafts.

  2. Interference Confocal Microscope Integrated with Spatial Phase Shifter.

    PubMed

    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

  3. 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

  4. Microscopic Polyangiitis

    MedlinePlus

    ... include purplish bumps and spots pictured below (palpable purpura). These areas range in size from several millimeters ... Syndrome (EGPA) Cryoglobulinemia Giant Cell Arteritis Henoch-Schönlein Purpura Microscopic Polyangiitis Polyarteritis Nodosa Rheumatoid Vasculitis Takayasu’s Arteritis ...

  5. An in situ investigation of Si[sub x]Ge[sub 1-x] chemical vapor deposition by differential reflectance

    SciTech Connect

    Sharp, J.W.

    1992-01-01

    An investigation of the surface kinetic processes of low pressure chemical vapor deposition (LPCVD) of Si, Ge, and Si[sub x]Ge[sub 1[minus]x] was carried out using time-resolved differential reflectance measurements. The source gas (disilane, digermane, or mixtures of these two diluted in a helium carrier) was delivered to a heated substrate by a fast-acting modulated molecular jet valve. Thin film growth was studied in the range of 400-500[degrees]C on Si and Ge (001) substrates. The kinetics of chemisorption and of by-product desorption were determined from the surface differential reflectance signal obtained using p-polarized, high-stability HeNe probe laser. Both chemisorption and by-product desorption were fond to obey first-order kinetics. Chemisorption of the parent molecules was found to be relatively efficient and weakly temperature dependent. For pure Si and Ge, by-product desorption occurred through a single first-order reaction. Two first-order desorption steps were inferred for the Si[sub x]Ge[sub 1[minus]x] alloy surfaces. These reactions are believed to be H[sub 2] desorption from Si-like and Ge-like surface sites. However, the activation energy of the more rapid of these two steps actually decreases as the Si content of the film increases. Generally, the films were of high crystalline quality and were very well aligned with the substrate. Preferential incorporation of digermane into the film produced an alloy composition that was Ge-rich relative to the gas composition. The primary accomplishment of this work is the demonstration that the active surface layer of the Si[sub x]Ge[sub 1[minus]x] system can be monitored in situ by an optical probe under typical LPCVD conditions. The results indicate that the rate-limiting step in Si or Ge LPCVD obeys simple first-order kinetics. Further work is needed to understand fully the rate-limiting surface reaction in Si[sub x]Ge[sub 1[minus]x] LPCVD.

  6. Levels of acyl-coenzyme A synthetase 5 in urothelial cells and corresponding neoplasias reflect cellular differentiation.

    PubMed

    Gaisa, Nadine T; Reinartz, Andrea; Schneider, Ursula; Klaus, Christina; Heidenreich, Axel; Jakse, Gerhard; Kaemmerer, Elke; Klinkhammer, Barbara Mara; Knuechel, Ruth; Gassler, Nikolaus

    2013-03-01

    Metabolic components like fatty acids and acyl-Coenzyme A (acyl-CoA) thioesters have been implicated in the pathogenesis of various tumours. The activation of fatty acids to acyl-CoAs is catalysed by long chain acyl-CoA synthetases (ACSLs), and impairment of ACSL expression levels has been associated with tumourigenesis and progression. Since ACSLs have never been investigated in bladder tissues, the study aims to characterize ACSL expression and acyl-CoA synthesis in normal and neoplastic bladder tissues, as well as cell lines. ACSL isoforms 1, 3, 4 and 5 and synthesis of acyl-CoAs were analysed using qRT-PCR, western blot analysis, immunohistochemistry and lipid mass spectrometry. In normal urothelium, expression of ACSL1, 3, 4 and 5, with highest levels of ACSL isoform 5 was found. However, ACSL5 expression was reduced in corresponding neoplastic tissues and urothelial cell lines depending on the grade of cellular differentiation. Anti-ACSL5 immunostainings showed expression in normal urothelium and a gradual loss of ACSL5 protein via pre-invasive lesions to invasive carcinomas. High expression of ACSL5 correlated with increased α-galactosidase activity and positive Uroplakin III staining in tumours. In contrast, synthesis of acyl-CoAs was enhanced in neoplastic bladder tissues compared to normal urothelium, and reflected an increase with respect to cellular differentiation. These results confirm an expression of ACSLs, especially isoform 5, in human urothelium, prove enzymatic/lipidomic changes in bladder cancer tissues, and suggest an involvement of ACSL5 in cellular maturation and/or senescence with possible effects onto induction of tumour formation or progression. Further work may identify responsible pathway alterations, and attempting to re-balance the metabolic equilibrium of the urothelium may offer a further opportunity for tumour treatment and prevention. PMID:23348389

  7. Rapid detection and differentiation of Alicyclobacillus species in fruit juice using hydrophobic grid membranes and attenuated total reflectance infrared microspectroscopy.

    PubMed

    Grasso, Elizabeth M; Yousef, Ahmed E; de Lamo Castellvi, Silvia; Rodriguez-Saona, Luis E

    2009-11-25

    Pasteurized juices may undergo spoilage during normal shelf life due to Alicyclobacillus spp. Metabolic byproducts during germination of these thermoacidiophilic, endospore-forming bacteria impart off-flavors. The objective was to develop a simple, rapid, and sensitive approach for differentiation of Alicyclobacillus spp. by attenuated total reflectance infrared (ATR-IR) microspectroscopy after isolation onto hydrophobic grid membrane (HGM) filters. Dilutions of four different species of Alicyclobacillus were filtered onto HGM, incubated on orange serum agar (50 degrees C, 36-48 h), and dried under vacuum. Spectra were collected using ATR-IR microspectroscopy and analyzed by multivariate analysis. Results indicated that soft independent modeling of class analogy models exhibited clusters that permitted classification at species and strain levels. The methodology was validated by correctly predicting Alicyclobacillus (100%) in blind tests. The proposed procedure permits chemically based classification of intact microbial cells. Implementation provides the juice industry with a rapid screening procedure to detect and monitor Alicyclobacillus that threatens the quality of pasteurized juices. PMID:19860470

  8. 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. PMID:27507476

  9. 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

  10. Simultaneous triple-modality imaging of diffuse reflectance, optoacoustic pressure and ultrasonic scattering using an acoustic-resolution photoacoustic microscope: feasibility study

    NASA Astrophysics Data System (ADS)

    Subochev, Pavel; Fiks, Ilya; Frenz, Martin; Turchin, llya

    2016-02-01

    The letter discusses the opportunity for cost-effective use of conventional optoacoustic hardware to realize additional imaging modalities such as ultrasonic microscopy and diffuse optical reflectometry within the same laser pulse. Optoacoustic methods for deep biomedical visualization are based on pulsed laser illumination of the internal tissue layers with scattered photons, however some of the back-scattered photons can be absorbed by the optoacoustic detector. Thermoelastic extension of the detector’s surface provides a probing pulse for an ultrasonic modality while the measurement of the amplitude of the probing ultrasonic pulse allows estimation of the diffuse reflectance from the object under investigation.

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. Investigations of nanoscale helical pitch in smectic-C*alpha and smectic-C* phases of a chiral smectic liquid crystal using differential optical reflectivity measurements.

    PubMed

    Panov, V P; McCoy, B K; Liu, Z Q; Vij, J K; Goodby, J W; Huang, C C

    2006-07-01

    Differential optical reflectivity (DOR) was used to study the temperature dependence of the short helical pitch in freestanding films of a liquid crystal compound. The experimentally measured DOR signal was fitted using Berreman's 4 x 4 matrix method to get the pitch value in the smectic-C*alpha (sMC*alpha) phase. The results show continuous evolution of the pitch between the smectic-C*alpha and sMC*alpha phases. In sMC*alpha, the pitch decreases as temperature increases and is found to level off at 16+/-1 smectic layers at the sMC*alpha to smectic-A* transition. PMID:16907105

  20. 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. PMID:20059064

  1. Dynamic Interplay of Smooth Muscle α-Actin Gene-Regulatory Proteins Reflects the Biological Complexity of Myofibroblast Differentiation

    PubMed Central

    Strauch, Arthur Roger; Hariharan, Seethalakshmi

    2013-01-01

    Myofibroblasts (MFBs) are smooth muscle-like cells that provide contractile force required for tissue repair during wound healing. The leading agonist for MFB differentiation is transforming growth factor β1 (TGFβ1) that induces transcription of genes encoding smooth muscle α-actin (SMαA) and interstitial collagen that are markers for MFB differentiation. TGFβ1 augments activation of Smad transcription factors, pro-survival Akt kinase, and p38 MAP kinase as well as Wingless/int (Wnt) developmental signaling. These actions conspire to activate β-catenin needed for expression of cyclin D, laminin, fibronectin, and metalloproteinases that aid in repairing epithelial cells and their associated basement membranes. Importantly, β-catenin also provides a feed-forward stimulus that amplifies local TGFβ1 autocrine/paracrine signaling causing transition of mesenchymal stromal cells, pericytes, and epithelial cells into contractile MFBs. Complex, mutually interactive mechanisms have evolved that permit several mammalian cell types to activate the SMαA promoter and undergo MFB differentiation. These molecular controls will be reviewed with an emphasis on the dynamic interplay between serum response factor, TGFβ1-activated Smads, Wnt-activated β-catenin, p38/calcium-activated NFAT protein, and the RNA-binding proteins, Purα, Purβ, and YB-1, in governing transcriptional and translational control of the SMαA gene in injury-activated MFBs. PMID:24832798

  2. 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.

  3. [The differentiated care model in the Special Indigenous Health Districts: reflections based on Alto Rio Negro in Amazonia State, Brazil].

    PubMed

    Pontes, Ana Lucia de Moura; Rego, Sergio; Garnelo, Luiza

    2015-10-01

    The implementation of the National Policy for Healthcare of Indigenous Peoples (Pnaspi) in the Alto Rio Negro Amazon region was analyzed based on the principles of the differentiated care model. This theme was investigated from three perspectives, namely the formulation of the guidelines, the therapeutic itineraries in indigenous villages, and the work routines of the Indigenous Community Health Agents (AIS). It involved qualitative research based on the anthropological perspective of Eduardo Menéndez. The techniques used were participant observation, interviews, and, document analysis. The formulation of the guidelines of differentiated care emphasizes the adaptation of technologies and professionals, minimizing the coexistence and disputes among healthcare models. Menéndez's perspective focused on the viewpoint of the subjects was crucial for identifying the coexistence and articulation among different forms of care in the villages through the healthcare itineraries. Nevertheless, it was not possible to identify the inclusion of indigenous health practices and representations through the work routines of the Indigenous Community Health Agents (AIS). The focus was on self-care developed and practiced by the subjects and their families. PMID:26465861

  4. 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.

  5. 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.

    PubMed

    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. PMID:22352662

  6. 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. PMID:26896150

  7. 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

  8. 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. PMID:26001124

  9. 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

  10. 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.

  11. 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. PMID:26996410

  12. Imaging Schwarzschild multilayer X-ray microscope

    NASA Astrophysics Data System (ADS)

    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.

  13. 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.

  14. 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

  15. The microscope mission

    NASA Astrophysics Data System (ADS)

    Touboul, Pierre; Foulon, Bernard; Lafargue, Laurent; Metris, Gilles

    2002-04-01

    The MICROSCOPE mission had been selected at the end of 1999 by the French space agency Cnes for a launch scheduled in 2004. The scientific objective of the mission is the test of the Equivalence Principle (EP) up to an accuracy of 10 -15 with its well-known manifestation, the universality of free fall. This principle, at the origin of general relativity, is only consolidated by experimental results and presently with an accuracy of several 10 -13. The micro-satellite developed by Cnes weighs less than 120 kg and is compatible with a low-cost launch like ASAP ARIANE V. The instrument is composed of two differential electrostatic accelerometers operating at finely stabilised room temperature. Each accelerometer includes two cylindrical and concentric test masses, made of platinum or titanium alloys. The experiment consists in controlling the two masses in the same orbital motion. Because of the drag compensation system of the satellite including field effect electrical thrusters, this motion is quite purely gravitational. The electrostatic control forces used in the differential accelerometers are finely measured. The principle of the experiment is presented, the configuration of the instrument and of the satellite is detailed with regard to the present development status. The specifications for the major parameters of the experiment are detailed.

  16. 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…

  17. 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.

  18. 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

    2016-01-01

    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

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. Increased BrdU incorporation reflecting DNA repair, neuronal de-differentiation or possible neurogenesis in the adult cochlear nucleus following bilateral cochlear lesions in the rat.

    PubMed

    Zheng, Yiwen; Begum, Shaeza; Zhang, Chu; Fleming, Kirk; Masumura, Chisako; Zhang, Ming; Smith, Paul; Darlington, Cynthia

    2011-05-01

    Neurogenesis is known to occur in response to injury in the brain, for example, as a result of neurodegenerative diseases. However, there have been few investigations into how the brain responds to damage to peripheral sensory nerves, in other areas such as the brainstem. Here, we report that bilateral surgical lesions of the cochlea result in increased incorporation of the DNA replication marker, bromodeoxyuridine (BrdU), in cells of the brainstem cochlear nucleus (CN) of the adult rat, suggesting either cell proliferation or DNA repair. Some of the BrdU-labelled cells colabelled for the mature neuron marker, NeuN and the GABAergic enzyme GAD-65, suggesting the possibility that neurogenesis might have occurred and resulted in the generation of new neurons with a GABAergic phenotype. However, some of the mature neurons also re-expressed immature neuronal intermediate filament and microtuble-associated proteins, without apoptotic neuronal death, which suggests that the colabelling of BrdU with NeuN and GAD-65 may not be a true reflection of neurogenesis, but injury-stimulated neuronal dedifferentiation. These results suggest the possibility that DNA repair, neuronal de-differentiation or possible neurogenesis occurs in the cochlear nucleus, in response to damage to the peripheral auditory system. PMID:21104237

  4. 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

  5. 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.

  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. Recurrence tracking microscope

    SciTech Connect

    Saif, Farhan

    2006-03-15

    In order to probe nanostructures on a surface we present a microscope based on the quantum recurrence phenomena. A cloud of atoms bounces off an atomic mirror connected to a cantilever and exhibits quantum recurrences. The times at which the recurrences occur depend on the initial height of the bouncing atoms above the atomic mirror, and vary following the structures on the surface under investigation. The microscope has inherent advantages over existing techniques of scanning tunneling microscope and atomic force microscope. Presently available experimental technology makes it possible to develop the device in the laboratory.

  9. [Wegener's granulomatosis and microscopic polyangiitis].

    PubMed

    Pagnoux, Christian

    2008-03-15

    Wegener's granulomatosis and microscopic polyangiitis are among the main systemic necrotizing vasculitides predominantly affecting small vessels. Their prevalences range from 24 to 157 cases per million inhabitants. Mean age at onset is usually 40 to 60 years old. Most common and suggestive features of Wegener's granulomatosis are upper (sinusitis, crusting rhinitis, saddle nose deformity, otitis media) and lower (excavated lung nodules, alveolar hemorrhage) respiratory tract, and kidney involvements. Alveolar hemorrhage and crescentic necrotizing glomerulonephritis are also characteristic manifestations of microscopic polyangiitis. Mononeuritis multiplex and necrotic purpura are frequent symptoms in both diseases. Antineutrophil cytoplasm autoantibodies (ANCA) directed against proteinase 3 can be found in the serum of 90% of the patients with diffuse forms of Wegener's granulomatosis, whereas ANCA with anti-myeloperoxidase specificity, whose pathogenic role is now well documented, can be detected in more than 60% of those with microscopic polyangiitis. Histologically, Wegener's granulomatosis can be differentiated from its counterpart when the inflammatory infiltrates have a granulomatous pattern. Therapy relies on the combination of corticosteroids and pulse intravenous cyclophosphamide, which can be switched, as soon as remission is achieved, to azathioprine or methotrexate, for a total duration of treatment of at least 18 months. Ten-year survival rate now exceeds 80%, but relapses are frequent. The precise place of new biologics, such as rituximab, needs to be further defined. PMID:18524109

  10. Mailing microscope slides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 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)

  12. 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…

  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. Surface imaging microscope

    NASA Astrophysics Data System (ADS)

    Rogala, Eric W.; Bankman, Isaac N.

    2008-04-01

    The three-dimensional shapes of microscopic objects are becoming increasingly important for battlespace CBRNE sensing. Potential applications of microscopic 3D shape observations include characterization of biological weapon particles and manufacturing of micromechanical components. Aerosol signatures of stand-off lidar systems, using elastic backscatter or polarization, are dictated by the aerosol particle shapes and sizes that must be well characterized in the lab. A low-cost, fast instrument for 3D surface shape microscopy will be a valuable point sensor for biological particle sensing applications. Both the cost and imaging durations of traditional techniques such as confocal microscopes, atomic force microscopes, and electron scanning microscopes are too high. We investigated the feasibility of a low-cost, fast interferometric technique for imaging the 3D surface shape of microscopic objects at frame rates limited only by the camera in the system. The system operates at two laser wavelengths producing two fringe images collected simultaneously by a digital camera, and a specialized algorithm we developed reconstructs the surface map of the microscopic object. The current implementation assembled to test the concept and develop the new 3D reconstruction algorithm has 0.25 micron resolution in the x and y directions, and about 0.1 micron accuracy in the z direction, as tested on a microscopic glass test object manufactured with etching techniques. We describe the interferometric instrument, present the reconstruction algorithm, and discuss further development.

  15. 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

  16. Stereoscopic Video Microscope

    NASA Astrophysics Data System (ADS)

    Butterfield, James F.

    1980-11-01

    The new electronic technology of three-dimensional video combined with the established. science of microscopy has created. a new instrument. the Stereoscopic Video Microscope. The specimen is illuminated so the stereoscopic objective lens focuses the stereo-pair of images side-by-side on the video camera's pick-up, tube. The resulting electronic signal can be enhanced, digitized, colorized, quantified, its polarity reverse., and its gray scale expanJed non-linearally. The signal can be transmitted over distances and can be stored on video. tape for later playback. The electronic signal is converted to a stereo-pair of visual images on the video monitor's cathode-ray-tube. A stereo-hood is used to fuse the two images for three-dimensional viewing. The conventional optical microscope has definite limitations, many of which can be eliminated by converting the optical image to an electronic signal in the video microscope. The principal aHvantages of the Stereoscopic Video Microscope compared to the conventional optical microscope are: great ease of viewing; group viewing; ability to easily recohd; and, the capability of processing the electronic signal for video. enhancement. The applications cover nearly all fields of microscopy. These include: microelectronics assembly, inspection, and research; biological, metallurgical, and che.illical research; and other industrial and medical uses. The Stereo-scopic Video Microscope is particularly useful for instructional and recordkeeping purposes. The video microscope can be monoscopic or three dimensional.

  17. [Microscopic colitis: update 2014].

    PubMed

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

    2014-09-01

    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. PMID:25276996

  18. 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.

  19. 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,…

  20. Hyperspectral confocal microscope

    NASA Astrophysics Data System (ADS)

    Sinclair, Michael B.; Haaland, David M.; Timlin, Jerilyn A.; Jones, Howland D. T.

    2006-08-01

    We have developed a new, high performance, hyperspectral microscope for biological and other applications. For each voxel within a three-dimensional specimen, the microscope simultaneously records the emission spectrum from 500 nm to 800 nm, with better than 3 nm spectral resolution. The microscope features a fully confocal design to ensure high spatial resolution and high quality optical sectioning. Optical throughput and detection efficiency are maximized through the use of a custom prism spectrometer and a backside thinned electron multiplying charge coupled device (EMCCD) array. A custom readout mode and synchronization scheme enable 512-point spectra to be recorded at a rate of 8300 spectra per second. In addition, the EMCCD readout mode eliminates curvature and keystone artifacts that often plague spectral imaging systems. The architecture of the new microscope is described in detail, and hyperspectral images from several specimens are presented.

  1. Hyperspectral confocal microscope.

    PubMed

    Sinclair, Michael B; Haaland, David M; Timlin, Jerilyn A; Jones, Howland D T

    2006-08-20

    We have developed a new, high performance, hyperspectral microscope for biological and other applications. For each voxel within a three-dimensional specimen, the microscope simultaneously records the emission spectrum from 500 nm to 800 nm, with better than 3 nm spectral resolution. The microscope features a fully confocal design to ensure high spatial resolution and high quality optical sectioning. Optical throughput and detection efficiency are maximized through the use of a custom prism spectrometer and a backside thinned electron multiplying charge coupled device (EMCCD) array. A custom readout mode and synchronization scheme enable 512-point spectra to be recorded at a rate of 8300 spectra per second. In addition, the EMCCD readout mode eliminates curvature and keystone artifacts that often plague spectral imaging systems. The architecture of the new microscope is described in detail, and hyperspectral images from several specimens are presented. PMID:16892134

  2. 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)

  3. Computerized Measuring Microscope

    NASA Astrophysics Data System (ADS)

    Schoonmaker, Thomas D.

    1980-05-01

    In the manufacturing of printed circuit boards, microscopic analysis is an essential process control activity. An inspector microscopically analyzes board samples to deter-mine board lot quality and process conditions. Prior to computerizing, this sustained measurement-taking involved the tedious process of recording raw data, converting microscope filar readings, calculating averages, logging information in a job notebook, and completing detailed final lab reports. It is evident from this brief task description that this time-consuming repetitious data recording routine was an added burden to the already fatiguing visual inspection method and therefore was a prime candidate for automatic data capture and printout. Secondly, the creation of a permanent and easily accessible data base would improve process feedback and provide for a system with quick identification of any suspect boards if further assembly/testing exhibited board-related failures. This paper describes the evolution and implementation of a computer-aided microscopic inspection operation.

  4. 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.

  5. 3D microscope

    NASA Astrophysics Data System (ADS)

    Iizuka, Keigo

    2008-02-01

    In order to circumvent the fact that only one observer can view the image from a stereoscopic microscope, an attachment was devised for displaying the 3D microscopic image on a large LCD monitor for viewing by multiple observers in real time. The principle of operation, design, fabrication, and performance are presented, along with tolerance measurements relating to the properties of the cellophane half-wave plate used in the design.

  6. 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

  7. 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. PMID:27223598

  8. 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)

  9. Microscopic overdiagnosis of intestinal amoebiasis.

    PubMed

    Rayan, Hanan Z E

    2005-12-01

    To determine the misdiagnosis of intestinal amoebiasis associated to microscopic examination of faeces, 50 stool samples of patients infected with Entamoeba histolytica were collected from different Primary Health Care Centers, hospitals and private laboratories in Ismailia G. The samples were examined using Wheatley's trichrome staining technique to differrentiate E. histolytica E. dispar complex from other non-pathogenic intestinal amoebae and multiplex polymerase chain reaction (PCR). PCR differentiated between the two morphologic identical species (E. histolytica and E. dispar) and had the advantage to save time and resources. E. histolytica was detected in only 5 (10%) samples and in association with E. dispar in 8 (16%) samples. On the other hand, 20 samples (40%) were E. dispar. The other 17 samples were negative. E. coli, E. hartmanni and polymorphs were commonly misdiagnosed as E. histolytica. PMID:16333901

  10. 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.

  11. 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.

  12. 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…

  13. Microscopic plasma Hamiltonian

    NASA Technical Reports Server (NTRS)

    Peng, Y.-K. M.

    1974-01-01

    A Hamiltonian for the microscopic plasma model is derived from the Low Lagrangian after the dual roles of the generalized variables are taken into account. The resulting Hamilton equations are shown to agree with the Euler-Lagrange equations of the Low Lagrangian.

  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. 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.

  16. 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.

  17. 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.

  18. 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

  19. Application of Zen sitting principles to microscopic surgery seating.

    PubMed

    Noro, Kageyu; Naruse, Tetsuya; Lueder, Rani; Nao-I, Nobuhisa; Kozawa, Maki

    2012-03-01

    This paper describes the application of an alternative seating concept for surgeons that reflects the research of Zen sitting postures, which require Zazen meditators to maintain fixed postures for long durations. The aim of this alternative approach is to provide sitters with a seat pan with sacral support(1) that provides a more even distribution of seat pressures, induces forward pelvic rotation and improves lumbar, buttock and thigh support. This approach was applied to the development of a chair for microscopic surgery. The experimental chair is a seat pan that closely matches the three-dimensional contours of the user's buttocks. Seat comfort was evaluated by comparing both changes in pelvic tilt and seat pressure distributions using Regionally-Differentiated Pressure Maps (RDPM) with subjective ratings of surgeons while operating in prototype and conventional chairs. Findings include that the sacral support of the prototype chair prevents backward pelvic rotation, as seen in zazen (Zen sitting postures). Preliminary data suggests that the prototype provided greater sitting comfort and support for constrained operating postures than did the conventional chair. These findings support the selective application of concave-shaped seat pans that conform to users' buttocks and reflect Zen sitting principles. PMID:21798514

  20. 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…

  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. 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

    2015-03-01

    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 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. PMID:25759526

  4. Focusing the surgical microscope.

    PubMed

    Socea, Sergiu D; Barak, Yoreh; Blumenthal, Eytan Z

    2015-01-01

    A well-focused operating microscope addresses several needs that are all secondary to the surgeon's need to see clearly at all times. These needs include: the assistant; the sharpness of the video and monitor; as well as field of view, asthenopia, and focusing issues related to zoom, accommodation, and presbyopia. We provide a practical approach to achieve optimal focus that we call the sloping paper calibration method. PMID:25891029

  5. Microscopic and macroscopic dynamics

    SciTech Connect

    Hoover, W.G.; Hoover, C.G.; De Groot, A.J.; Pierce, T.G. |

    1993-06-01

    Atomistic Molecular Dynamics and Lagrangian Continuum Mechanics can be very similarly adapted to massively-parallel computers. Millions of degrees of freedom can be treated. The two complementary approaches, microscopic and macroscopic, are being applied to increasingly realistic flows of fluids and solids. The two approaches can also be combined in a hybrid simulation scheme. Hybrids combine the fundamental constitutive advantage of atoms with the size advantage of the continuum picture.

  6. 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

  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. Estimation of semiconductor-like pigment concentrations in paint mixtures and their differentiation from paint layers using first-derivative reflectance spectra.

    PubMed

    Pallipurath, Anuradha R; Skelton, Jonathan M; Ricciardi, Paola; Elliott, Stephen R

    2016-07-01

    Identification of the techniques employed by artists, e.g. mixing and layering of paints, if used together with information about their colour palette and style, can help to attribute works of art with more confidence. In this study, we show how the pigment composition in binary paint mixtures can be quantified using optical-reflectance spectroscopy, by analysis of the peak features corresponding to colour-transition edges in the first-derivative spectra. This technique is found to be more robust than a number of other spectral-analysis methods, which can suffer due to shifts in the transition edges in mixed paints compared to those observed in spectra of pure ones. Our method also provides a means of distinguishing paint mixtures from layering in some cases. The spectroscopy also shows the presence of multiple electronic transitions, accessible within a narrow energy range, to be a common feature of many coloured pigments, which electronic-structure calculations attribute to shallow band edges. We also demonstrate the successful application of the reflectance-analysis technique to painted areas on a selection of medieval illuminated manuscripts. PMID:27154649

  9. Point Scanning Microscope with Adaptive Illumination Beam Intensity

    NASA Astrophysics Data System (ADS)

    Das, Abhijit; Boruah, B. R.

    2011-10-01

    In this paper we describe a point scanning optical microscope where the illumination beam can be programmably controlled in real time using a liquid crystal spatial light modulator (LCSLM). With an appropriate pattern displayed on the LCSLM, the device can be made to act as a binary diffraction hologram. In the proposed microscope the illumination beam is in fact the +1 order beam diffracted from the binary hologram. By displaying a sequence of binary holograms it is possible to make a beam scanning, similar to a conventional scanning microscope. Here we use a computer generated holography technique to compute the binary holograms which facilitate complete control of the amplitude and phase profile of the illumination beam. In a number of microscopy applications using reflected light, the reflectivity of the sample plane may differ from region to region. Therefore if a single illumination beam intensity is used for the whole sample plane, then the regions with less reflectivity will be imaged with poor signal to noise ratio. In our proposed microscope the sample plane is first imaged to determine the regions of weak reflectivity. Holograms are then computed to make the illumination beam adapt to the reflectivity variations in the given sample plane. The image obtained with the modified set of holograms have superior signal to noise ratio all over, relative to a conventional point scanning microscope with a fixed intensity illumination beam. In this paper we present some preliminary results using the proposed setup.

  10. 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.

  11. [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

  12. 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.

  13. 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.

  14. Photography with a Microscope

    NASA Astrophysics Data System (ADS)

    Rost, Fred; Oldfield, Ron

    2000-03-01

    This beautifully illustrated book describes the methods used to record images viewed through a microscope. The text describes the principles and practices of photomicrography, and is written for all who take photomicrographs, beginners and/or experienced practitioners. The authors describe techniques that may be applied to many disciplines for teaching, research, archives, or pleasure. The book includes chapters on standard photography, modern digital techniques, methods for improving contrast, and a short chapter on drawing. In addition to its value as a work of reference, the authors' clear, didactic style makes this book suitable as a textbook for courses in photomicrography and/or elementary light microscopy.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Hyperspectral unmixing using macroscopic and microscopic mixture models

    NASA Astrophysics Data System (ADS)

    Close, Ryan; Gader, Paul; Wilson, Joseph

    2014-01-01

    Macroscopic and microscopic mixture models and algorithms for hyperspectral unmixing are presented. Unmixing algorithms are derived from an objective function. The objective function incorporates the linear mixture model for macroscopic unmixing and a nonlinear mixture model for microscopic unmixing. The nonlinear mixture model is derived from a bidirectional reflectance distribution function for microscopic mixtures. The algorithm is designed to unmix hyperspectral images composed of macroscopic or microscopic mixtures. The mixture types and abundances at each pixel can be estimated directly from the data without prior knowledge of mixture types. Endmembers can also be estimated. Results are presented using synthetic data sets of macroscopic and microscopic mixtures and using well-known, well-characterized laboratory data sets. The unmixing accuracy of this new physics-based algorithm is compared to linear methods and to results published for other nonlinear models. The proposed method achieves the best unmixing accuracy.

  20. Are species shade and drought tolerance reflected in leaf-level structural and functional differentiation in Northern Hemisphere temperate woody flora?

    PubMed

    Hallik, Lea; Niinemets, Ulo; Wright, Ian J

    2009-01-01

    Leaf-level determinants of species environmental stress tolerance are still poorly understood. Here, we explored dependencies of species shade (T(shade)) and drought (T(drought)) tolerance scores on key leaf structural and functional traits in 339 Northern Hemisphere temperate woody species. In general, T(shade) was positively associated with leaf life-span (L(L)), and negatively with leaf dry mass (M(A)), nitrogen content (N(A)), and photosynthetic capacity (A(A)) per area, while opposite relationships were observed with drought tolerance. Different trait combinations responsible for T(shade) and T(drought) were observed among the key plant functional types: deciduous and evergreen broadleaves and evergreen conifers. According to principal component analysis, resource-conserving species with low N content and photosynthetic capacity, and high L(L) and M(A), had higher T(drought), consistent with the general stress tolerance strategy, whereas variation in T(shade) did not concur with the postulated stress tolerance strategy. As drought and shade often interact in natural communities, reverse effects of foliar traits on these key environmental stress tolerances demonstrate that species niche differentiation is inherently constrained in temperate woody species. Different combinations of traits among key plant functional types further explain the contrasting bivariate correlations often observed in studies seeking functional explanation of variation in species environmental tolerances. PMID:19674334

  1. 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. PMID:24860871

  2. 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.

  3. 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.

  4. 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.

  5. TRANSCRIPTOME ANALYSES REVEAL DIFFERENTIAL GENE EXPRESSION PATTERNS BETWEEN THE LIFE-CYCLE STAGES OF EMILIANIA HUXLEYI (HAPTOPHYTA) AND REFLECT SPECIALIZATION TO DIFFERENT ECOLOGICAL NICHES(1).

    PubMed

    Rokitta, Sebastian D; de Nooijer, Lennart J; Trimborn, Scarlett; de Vargas, Colomban; Rost, Björn; John, Uwe

    2011-08-01

    Coccolithophores, especially the abundant, cosmopolitan species Emiliania huxleyi (Lohmann) W. W. Hay et H. P. Mohler, are one of the main driving forces of the oceanic carbonate pump and contribute significantly to global carbon cycling, due to their ability to calcify. A recent study indicates that termination of diploid blooms by viral infection induces life-cycle transition, and speculation has arisen about the role of the haploid, noncalcifying stage in coccolithophore ecology. To explore gene expression patterns in both life-cycle stages, haploid and diploid cells of E. huxleyi (RCC 1217 and RCC 1216) were acclimated to limiting and saturating photon flux densities. Transcriptome analyses were performed to assess differential genomic expression related to different ploidy levels and acclimation light intensities. Analyses indicated that life-cycle stages exhibit different properties of regulating genome expression (e.g., pronounced gene activation and gene silencing in the diploid stage), proteome maintenance (e.g., increased turnover of proteins in the haploid stage), as well as metabolic processing (e.g., pronounced primary metabolism and motility in the haploid stage and calcification in the diploid stage). Furthermore, higher abundances of transcripts related to endocytotic and digestive machinery were observed in the diploid stage. A qualitative feeding experiment indicated that both life-cycle stages are capable of particle uptake (0.5 μm diameter) in late-stationary growth phase. Results showed that the two life-cycle stages represent functionally distinct entities that are evolutionarily shaped to thrive in the environment they typically inhabit. PMID:27020019

  6. 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

  7. 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.

  8. Virtual reflected-light microscopy.

    PubMed

    Harrison, A P; Wong, C M; Joseph, D

    2011-12-01

    Research on better methods to digitally represent microscopic specimens has increased over recent decades. Opaque specimens, such as microfossils and metallurgic specimens, are often viewed using reflected light microscopy. Existing 3D surface estimation techniques for reflected light microscopy do not model reflectance, restricting the representation to only one illumination condition and making them an imperfect recreation of the experience of using an actual microscope. This paper introduces a virtual reflected-light microscopy (VRLM) system that estimates both shape and reflectance from a set of specimen images. When coupled with anaglyph creation, the system can depict both depth information and illumination cues under any desired lighting configuration. Digital representations are compact and easily viewed in an online setting. A prototype used to construct VRLM representations is comprised only of a microscope, a digital camera, a motorized stage and software. Such a system automatically acquires VRLM representations of large batches of specimens. VRLM representations are then disseminated in an interactive online environment, which allows users to change the virtual light source direction and type. Experiments demonstrate high quality VRLM representations of 500 microfossils. PMID:21919903

  9. THz wave emission microscope

    NASA Astrophysics Data System (ADS)

    Yuan, Tao

    Sensing and imaging using Terahertz (THz) radiation has attracted more and more interest in the last two decades thanks to the abundant material 'finger prints' in the THz frequency range. The low photon energy also makes THz radiation an attractive tool for nondestructive evaluation of materials and devices, biomedical applications, security checks and explosive screening. Due to the long wavelength, the far-field THz wave optical systems have relatively low spatial resolution. This physical limitation confines THz wave sensing and imaging to mostly macro-size samples. To investigate local material properties or micro-size structures and devices, near-field technology has to be employed. In this dissertation, the Electro-Optical THz wave emission microscope is investigated. The basic principle is to focus the femtosecond laser to a tight spot on a thin THz emitter layer to produce a THz wave source with a similar size as the focus spot. The apparatus provides a method for placing a THz source with sub-wavelength dimension in the near-field range of the investigated sample. Spatial resolution to the order of one tenth of the THz wavelength is demonstrated by this method. The properties of some widely used THz wave emission materials under tight focused pump light are studied. As an important branch of THz time domain spectroscopy (THz-TDS), THz wave emission spectroscopy has been widely used as a tool to investigate the material physics, such as energy band structure, carrier dynamics, material nonlinear properties and dynamics. As the main work of this dissertation, we propose to combine the THz wave emission spectroscopy with scanning probe microscopy (SPM) to build a tip-assisted THz wave emission microscope (TATEM), which is a valuable extension to current SPM science and technology. Illuminated by a femtosecond laser, the biased SPM tip forms a THz wave source inside the sample beneath the tip. The source size is proportional to the apex size of the tip so

  10. 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.

  11. Surface Detection in a STXM Microscope

    SciTech Connect

    Behyan, S.; Haines, B.; Urquhart, S. G.; Karanukaran, C.; Wang, J.; Obst, M.; Tyliszczak, T.

    2011-09-09

    We have modified scanning transmission x-ray microscopes (STXM) at the Canadian Light Source and the Advanced Light Source with total electron yield (TEY) detection (TEY-STXM). This provides improved surface-sensitive detection, simultaneous with existing bulk-sensitive transmission detection in the STXM microscopes. We have explored sample-current and channeltron-based electron yield detection. Both approaches provide improved surface sensitive imaging and spectroscopy, although channeltron-based detection is superior. TEY-STXM provides surface sensitive imaging of ultrathin films such as phase-separated Langmuir-Blodgett monolayer films, as well as differentiation of surface and bulk oxides of patterned metallic thin films. This paper will outline the experimental challenges of this method and the opportunities for correlative surface and bulk measurements of complex samples.

  12. Imaging arrangement and microscope

    DOEpatents

    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.

  13. 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.

  14. 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.

  15. Reflected Glory

    ERIC Educational Resources Information Center

    Forster, Colin

    2006-01-01

    The scientific model of how people see things is far removed from children's real-world experience. They know that light is needed in order to see an object, but may not know that light is reflected off the object and some of that light enters the eyes. In this article, the author explores children's understanding of reflection and how to develop…

  16. 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.

  17. 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.

  18. Microscope Would Image X and Gamma Rays

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.

    1991-01-01

    Microscope contains Bragg-reflecting, grazing-incidence reflectors, filter wheel, and detector. Multiple nested coaxial pairs of reflectors used to form images simultaneously at multiple wavelengths. Collects and focuses radiation to produce images with moderate spectral resolution and high spatial resolution. Enables use of smaller, cheaper, better-shielded detectors. Combination of features provides new information of unprecedented value in several fields of research; probing fine structures of pulsed plasmas, investigating minute variations in structures of material specimens penetrated only by hard-x or gamma rays, or in producing maps of distributions of radioisotopes in biological specimens.

  19. Twisted bi-layer graphene: microscopic rainbows.

    PubMed

    Campos-Delgado, J; Algara-Siller, G; Santos, C N; Kaiser, U; Raskin, J-P

    2013-10-11

    Blue, pink, and yellow colorations appear from twisted bi-layer graphene (tBLG) when transferred to a SiO2 /Si substrate (SiO2 = 100 nm-thick). Raman and electron microscope studies reveal that these colorations appear for twist angles in the 9-15° range. Optical contrast simulations confirm that the observed colorations are related to the angle-dependent electronic properties of tBLG combined with the reflection that results from the layered structure tBLG/100 nm-thick SiO2 /Si. PMID:23606323

  20. 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. PMID:23931502

  1. 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.

  2. Fiber optic confocal microscope: In vivo precancer detection

    NASA Astrophysics Data System (ADS)

    Carlson, Kristen Dawn

    Cancer is a significant public health problem worldwide. Many cancers originate as precancerous lesions in the epithelium which, when removed in sufficient time, can prevent progression to cancer. However, current detection techniques are typically time-consuming and expensive, limiting their acceptance and accessibility. Optical techniques, such as confocal microscopy, have significant potential to provide clinicians with real-time, high-resolution images of cells and tissue without tissue removal. These images of cell morphology and tissue architecture can be used to characterize tissue and determine the presence or extent of precancer and cancer. This dissertation explores the instrumentation and application of fiber optic reflectance confocal microscopy for in vivo precancer detection. The first part of the dissertation presents in vivo imaging of suspicious lesions in the human uterine cervix and oral mucosa using a fiber bundle based confocal microscope with a complex glass miniature objective lens. Images are analyzed quantitatively and qualitatively to determine the potential of this technology in vivo. An analysis of nuclear density from images of 30 cervical epithelium sites shows differentiation between normal and precancerous sites. Similarly, images from 20 oral mucosa sites demonstrate changes in nuclear density and tissue architecture indicative of progression of precancer and cancer. In addition to this multi-fiber confocal microscope used with a glass objective lens for the clinical studies, imaging of tissue samples has been accomplished with the same confocal system using an injection molded plastic miniature objective lens demonstrating comparable optical quality for a significantly less expensive optical component. Finally, a benchtop prototype of a single fiber confocal microscope using a gimbaled two-axis MEMS scanner has been designed and constructed. Imaging of a resolution target and cellular samples demonstrates sufficient resolution and

  3. Athena microscopic Imager investigation

    USGS Publications Warehouse

    Herkenhoff, K. E.; Squyres, S. W.; Bell, J.F., III; 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.

  4. Microscopic Chondritic Chemical Reactors

    NASA Astrophysics Data System (ADS)

    Maurette, Michel

    Maurette (1998a and 1998b) gives a more detailed discussion of previous works supporting the role of unmelted micrometeorites in prebiotic chemistry. Krueger and Kissel (1987) quoted thermodynamic computations suggesting that the μm-size C-rich grains that they discovered in the tail of Halley’s comet with their time-of-flight mass spectrometer on board the Vega spacecraft, when added to a prebiotic soup of organics, could trigger the formation of nucleic acids. Anders (1989) relied on the characteristics of the tiny stratospheric micrometeorites with sizes of about 5 15 μm, which amount to less than about 1% of the micrometeorite mass flux, to argue that micrometeorites played a major role in the delivery of organics to the Earth. As first quoted by Ponchelet (1989), we proposed in 1989 that much larger micrometeorites, similar to Antarctic micrometeorites, might have been functioning as individual microscopic chemical reactors on the early Earth during their interactions with gases and waters (Maurette et al., 1990, 1991b, 1998a, 1998b). Subsequently, Chyba and Sagan (1992) ceased fully supporting the role of the direct impact of comets in the delivery of such organics, and started to refer that of micrometeorites.

  5. 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…

  6. 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.

  7. Imaging Microscope For "Water-Window" X Rays

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.

    1991-01-01

    Proposed microscope operates in "water-window" part of x-ray spectrum. Contains spherical-mirror substrates coated with multiple thin layers of material exhibiting Bragg reflection at wavelength at which water transparent. Suited for making high-resolution, high-contrast images for microbiological research.

  8. 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.

  9. Shape quantification of single red blood cells based on their scattering patterns from microscopic images

    NASA Astrophysics Data System (ADS)

    Schneider, Gert; Artmann, Gerhard

    1995-02-01

    The differentiation between discocytic and stomatocytic red blood cell (RBC) shape using conventional microscopic imaging and image analysis tools is still on a very poor level. A procedure to differentiate the degree of stomatocytic shape changes was developed. We obtained multiple microscopic images of the same RBCs settled on a human albumin coated cover slip. The images were acquired when the microscope objective was subsequently focused through the cell layer. At equidistant horizontal planes (z-axis) below, within, and above the microscopic focal plane the light intensity distribution was considered. Using a model based on light refraction, we calculated the intensity distribution of the planes which are out of focus. Using this tool we are able to differentiate RBC shapes precisely. On the other hand, using this model from and the light intensity distributions of different focal planes, we are able to reconstruct the shape of one single RBC located in the optical axis of the microscope.

  10. Reflective Learning

    ERIC Educational Resources Information Center

    Morales, Stephen

    2011-01-01

    In this article, the author presents his study of parent participation at an international school in Spain offering the British curriculum. He used quantitative methods and administered questionnaires to gather data that reflected the views of a large proportion of the school's parent community. He administered semi-structured interviews to gain a…

  11. 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.

  12. (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.

  13. Center of excellence: Microlaser microscope

    NASA Astrophysics Data System (ADS)

    Webb, R. H.

    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.

  14. 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.

  15. 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)

  16. 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.

  17. 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.

  18. Microscopic traffic modelling in urban noise assessment

    NASA Astrophysics Data System (ADS)

    de Coensel, Bert; Botteldooren, Dick; de Muer, Tom; Peeters, Bert; van Blokland, Gijsjan

    2005-04-01

    The temporal structure of the urban soundscape can be rather complex, due to the presence of many screening and reflecting surfaces and many different sound sources, of which traffic noise is the most dominant. From the point of view of soundscape research, the background level as well as the time structure of noise peaks are important. However, these indicators cannot be estimated easily by current noise prediction models, based on static traffic flows. Therefore, a dynamic traffic noise model was used, based on a microscopic traffic simulation. This way, individual vehicles can be traced, each having an associated set of noise sources that can depend on vehicle properties such as speed and acceleration, as well as on road properties such as the surface type. The model further consists of an ISO 9613 based propagation component, which can account for multiple reflections and diffractions. Maps of statistical noise levels, but also of more complicated measures reflecting the time structure of the soundscape, can be produced. This way, the soundscape contribution of single vehicles can be traced, as well as the influence of more general vehicle properties, such as the contribution of vehicle acceleration noise to the soundscape at junctions.

  19. 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.

  20. Haitian reflections.

    PubMed

    Docrat, Fathima

    2010-08-01

    Natural disasters and acts of terrorism demonstrate a similar critical need for national preparedness. As one of a team of volunteers with a local South African NGO who recently went on a medical mission, I would like to share glimpses of our experience and reflect on the mistakes - and also to state the obvious: that we do not learn from our mistakes. A simple literature search has shown that the same mistakes happen repeatedly. 'Humanitarian disasters occur with frightening regularity, yet international responses remain fragmented, with organizations and responders being forced to "reinvent the wheel" with every new event'. This is the result of an obvious lack of preparedness. PMID:20822625

  1. 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.

  2. 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.

  3. 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.

  4. High Resolution Neutral Atom Microscope

    NASA Astrophysics Data System (ADS)

    Bucay, Igal; Castillo-Garza, Rodrigo; Stratis, Georgios; Raizen, Mark

    2015-03-01

    We are developing a high resolution neutral atom microscope based on metastable atom electron spectroscopy (MAES). When a metastable atom of a noble gas is near a solid, a surface electron will tunnel to an empty energy level of the metastable atom, thereby ejecting the excited electron from the atom. The emitted electrons carry information regarding the local topography and electronic, magnetic, and chemical structures of most hard materials. Furthermore, using a chromatic aberration corrected magnetic hexapole lens we expect to attain a spatial resolution below 10 nm. We will use this microscope to investigate how local phenomena can give rise to macroscopic effects in materials that cannot be probed using a scanning tunneling microscope, namely insulating transition metal oxides.

  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. 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.

  7. Developing a Quantum Electron Microscope

    NASA Astrophysics Data System (ADS)

    Kohstall, Christoph; Klopfer, Brannon; Francis, Josh; Skulason, Gunnar; Juffmann, Thomas; Kasevich, Mark; QEM Team

    2014-03-01

    We develop a new electron microscope based on the interaction-free measurement principle. Such a Quantum Electron Microscope (QEM) may enable imaging of biological samples with radiation doses so small that they are non-lethal. The realization of the QEM will require precise control over the quantum motion of free electrons. On this poster, we discuss our approach to build a QEM including the realization of an electron resonator and an electron amplitude beam-splitter. On top of the QEM application, these developments will advance the electron analogue to photon quantum optics. Funded by the Gordon and Betty Moore Foundation.

  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. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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

  14. 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

  15. Light-Fueled Microscopic Walkers.

    PubMed

    Zeng, Hao; Wasylczyk, Piotr; Parmeggiani, Camilla; Martella, Daniele; Burresi, Matteo; Wiersma, Diederik Sybolt

    2015-07-01

    The first microscopic artificial walker equipped with liquid-crystalline elastomer muscle is reported. The walker is fabricated by direct laser writing, is smaller than any known living terrestrial creatures, and is capable of several autonomous locomotions on different surfaces. PMID:26033690

  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. Toolmaker's Microscope With Video Monitor

    NASA Technical Reports Server (NTRS)

    Ahmed, Arif S.

    1988-01-01

    Display accessories increase resolution and flexibility of use. Toolmaker's microscope equipped with video monitor, auxiliary lighting, and high-resolution readout devices enables noncontacting measurements of tiny slots, indentations, and similar features on parts. Measures places difficult or impossible to reach by mechanical means.

  18. 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.

  19. 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)

  20. 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)

  1. 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.

  2. 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.…

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. Light microscopic and electron microscopic histopathology of an iris microhaemangioma.

    PubMed Central

    Meades, K V; Francis, I C; Kappagoda, M B; Filipic, M

    1986-01-01

    A patient who had been observed to have an iris microhaemangioma (capillary haemangioma), confirmed on fluorescein iris angiography, came to cataract surgery. The lesion was excised at the time of surgery and submitted to light and electron microscopic study. It had the features of a hamartoma of the capillary haemangioma type, with its characteristics being specific for vessels seen in iris tissue. Images PMID:3964627

  8. 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.

  9. Shear Brillouin light scattering microscope.

    PubMed

    Kim, Moonseok; Besner, Sebastien; Ramier, Antoine; Kwok, Sheldon J J; An, Jeesoo; Scarcelli, Giuliano; Yun, Seok Hyun

    2016-01-11

    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

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. Super-parallel MR microscope.

    PubMed

    Matsuda, Yoshimasa; Utsuzawa, Shin; Kurimoto, Takeaki; Haishi, Tomoyuki; Yamazaki, Yukako; Kose, Katsumi; Anno, Izumi; Marutani, Mitsuhiro

    2003-07-01

    A super-parallel MR microscope in which multiple (up to 100) samples can be imaged simultaneously at high spatial resolution is described. The system consists of a multichannel transmitter-receiver system and a gradient probe array housed in a large-bore magnet. An eight-channel MR microscope was constructed for verification of the system concept, and a four-channel MR microscope was constructed for a practical application. Eight chemically fixed mouse fetuses were simultaneously imaged at the 200 micro m(3) voxel resolution in a 1.5 T superconducting magnet of a whole-body MRI, and four chemically fixed human embryos were simultaneously imaged at 120 micro m(3) voxel resolution in a 2.35 T superconducting magnet. Although the spatial resolutions achieved were not strictly those of MR microscopy, the system design proposed here can be used to attain a much higher spatial resolution imaging of multiple samples, because higher magnetic field gradients can be generated at multiple positions in a homogeneous magnetic field. PMID:12815693

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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…

  7. 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

  8. Study of factors affecting the appearance of colors under microscopes

    NASA Astrophysics Data System (ADS)

    Zakizadeh, Roshanak; Martinez-Garcia, Juan; Raja, Kiran B.; Siakidis, Christos

    2013-11-01

    The variation of colors in microscopy systems can be quite critical for some users. To address this problem, a study is conducted to analyze how different factors such as size of the sample, intensity of the microscope's light source and the characteristics of the material like chroma and saturation can affect the color appearance through the eyepiece of the microscope. To study the changes in colors considering these factors, the spectral reflectance of 24 colors of GretagMacbeth Classic ColorChecker® and Mini ColorChecker® which are placed under a Nikon ECLIPSE MA200 microscope®2 using dark filed and bright field illuminations which result in different intensity levels, is measured using a spectroradiometer®3 which was placed in front of the eyepiece of the microscope. The results are compared with the original data from N. Ohta1. The evaluation is done by observing the shift in colors in the CIE 1931 Chromaticity Diagram and the CIELAB space, also by applying a wide set of color-difference formulas, namely: CIELAB, CMC, BFD, CIE94, CIEDE2000, DIN99d and DIN99b. Furthermore, to emphasize on the color regions in which the highest difference is observed, the authors have obtained the results from another microscope; Olympus SZX10®4, which in this case the measurement is done by mounting the spectroradiometer to the camera port of the microscope. The experiment leads to some interesting results, among which is the consistency in the highest difference observed considering different factors or how the change in saturation of the samples of the same hue can affect the results.

  9. 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.

  10. 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.…

  11. 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.…

  12. 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.

  13. Coaxial atomic force microscope tweezers

    NASA Astrophysics Data System (ADS)

    Brown, K. A.; Aguilar, J. A.; Westervelt, R. M.

    2010-03-01

    We demonstrate coaxial atomic force microscope (AFM) tweezers that can trap and place small objects using dielectrophoresis (DEP). An attractive force is generated at the tip of a coaxial AFM probe by applying a radio frequency voltage between the center conductor and a grounded shield; the origin of the force is found to be DEP by measuring the pull-off force versus applied voltage. We show that the coaxial AFM tweezers can perform three-dimensional assembly by picking up a specified silica microsphere, imaging with the microsphere at the end of the tip, and placing it at a target destination.

  14. Stimulated Brillouin Scattering Microscopic Imaging

    NASA Astrophysics Data System (ADS)

    Ballmann, Charles W.; Thompson, Jonathan V.; Traverso, Andrew J.; Meng, Zhaokai; Scully, Marlan O.; Yakovlev, Vladislav V.

    2015-12-01

    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.

  15. Stimulated Brillouin Scattering Microscopic Imaging.

    PubMed

    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

  16. 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.

  17. 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

  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. 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

  1. Endoscopic and Microscopic Microvascular Decompression.

    PubMed

    Piazza, Matthew; Lee, John Y K

    2016-07-01

    The introduction of the endoscope into the neurosurgeon's armamentarium has revolutionized ventral and anterior skull-base surgery and, more recently, has been used in the surgical treatment of cerebellopontine angle (CPA) pathology. The utilization of the endoscope in microvascular decompression (MVD) for trigeminal neuralgia and other associated cranial nerve hyperactivity syndromes allows for unparalleled panoramic views and illumination of the neurovascular structures within the CPA and identification of vessel-nerve contact traditionally unseen using the microscope. In this article, the technical advantages and challenges of using the endoscope for MVD, operative technique, and patient outcomes of endoscopic MVD are discussed. PMID:27324997

  2. Inspection 13.2 nm table-top full-field microscope

    SciTech Connect

    Brizuela, F.; Wang, Y.; Brewer, C. A.; Pedaci, F.; Chao, W.; Anderson, E. H.; Liu, Y.; Goldberg, K. A.; Naulleau, P.; Wachulak, P.; Marconi, M. C.; Attwood, D. T.; Rocca, J. J.; Menoni, C. S.

    2009-02-23

    We present results on a table-top microscope that uses an EUV stepper geometry to capture full-field images with a halfpitch spatial resolution of 55 nm. This microscope uses a 13.2 nm wavelength table-top laser for illumination and acquires images of reflective masks with exposures of 20 seconds. These experiments open the path to the realization of high resolution table-top imaging systems for actinic defect characterization.

  3. Interlaboratory Reproducibility of Blood Morphology Using the Digital Microscope.

    PubMed

    Riedl, Jurgen A; Stouten, Karlijn; Ceelie, Huib; Boonstra, Joke; Levin, Mark-David; van Gelder, Warry

    2015-12-01

    Differential counting of peripheral blood cells is an important diagnostic tool. However, manual morphological analysis using the microscope is time-consuming and requires highly trained personnel. The digital microscope is capable of performing an automated peripheral blood cell differential, which is as reliable as manual classification by experienced laboratory technicians. To date, information concerning the interlaboratory variation and quality of cell classification by independently operated digital microscopy systems is limited. We compared four independently operated digital microscope systems for their ability in classifying the five main peripheral blood cell classes and detection of blast cells in 200 randomly selected samples. Set against the averaged results, the R(2) values for neutrophils ranged between 0.90 and 0.96, for lymphocytes between 0.83 and 0.94, for monocytes between 0.77 and 0.82, for eosinophils between 0.70 and 0.78, and for blast cells between 0.94 and 0.99. The R(2) values for the basophils were between 0.28 and 0.34. This study shows that independently operated digital microscopy systems yield reproducible preclassification results when determining the percentages of neutrophils, eosinophils, lymphocytes, monocytes, and blast cells in a peripheral blood smear. Detection of basophils was hampered by the low incidence of this cell class in the samples. PMID:25925737

  4. Scanned optical fiber confocal microscope

    NASA Astrophysics Data System (ADS)

    Dickensheets, David L.; Kino, Gordon S.

    1994-04-01

    The size and weight of conventional optical microscopes often makes them inconvenient for use on the human body or for in-situ examination during materials processing. We describe a new fiber-optic scanning confocal optical microscope which could have a total outside diameter as small as 1 mm, and should lend itself to applications in endoscopy or to optical in vivo histology. The first experimental device utilizes a single-mode optical fiber for illumination and detection. The scanning element is a mechanically resonant fused silica cantilever 1.5 cm long and 0.8 mm across, with a micromachined two-phase zone plate objective mounted at one end. The cantilever is electrostatically scanned near resonance in two dimensions, generating a Lissajous pattern which is scan converted to conventional video for real time display or digitization. The objective lens has N.A. equals 0.25 at (lambda) equals 0.6328 micrometers , with a measured spot size of 1.8 micrometers FWHM.

  5. 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.

  6. 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.

  7. 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.

  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. 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.

  10. Microscopic x-ray luminescence computed tomography

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Zhu, Dianwen; Zhang, Kun; Li, Changqing

    2015-03-01

    X-ray luminescence computed tomography (XLCT) was emerged as a new hybrid imaging modality, in which the x-rays are used to excite phosphors emitting optical photons to be measured for imaging. In this paper, we reported a microscopic x-ray luminescence computed tomography (microXLCT) with a spatial resolution up to hundreds of micrometers for deep targets. We use a superfine x-ray pencil beam to scan the phosphor targets. The superfine x-ray pencil beam is generated by a small collimator mounted in front of a powerful x-ray tube (93212, Oxford Instrument). A CT detector is used to image the x-ray beam. We have generated an x-ray beam with a diameter of 192 micrometers with a collimator of 100 micrometers in diameter. The emitted optical photons on the top surface of phantom are reflected by a mirror and acquired by an electron multiplier charge-coupled device (EMCCD) camera (C9100-13, Hamamatsu Photonics). The microXLCT imaging system is built inside an x-ray shielding and light tight cabinet. The EMCCD camera is placed in a lead box. All the imaging components are controlled by a VC++ program. The optical photon propagation is modeled with the diffusion equation solved by the finite element method. We have applied different regularization methods including L2 and L1 in the microXLCT reconstruction algorithms. Numerical simulations and phantom experiments are used to validate the microXLCT imaging system.

  11. Precise autofocusing microscope with rapid response

    NASA Astrophysics Data System (ADS)

    Liu, Chien-Sheng; Jiang, Sheng-Hong

    2015-03-01

    The rapid on-line or off-line automated vision inspection is a critical operation in the manufacturing fields. Accordingly, this present study designs and characterizes a novel precise optics-based autofocusing microscope with a rapid response and no reduction in the focusing accuracy. In contrast to conventional optics-based autofocusing microscopes with centroid method, the proposed microscope comprises a high-speed rotating optical diffuser in which the variation of the image centroid position is reduced and consequently the focusing response is improved. The proposed microscope is characterized and verified experimentally using a laboratory-built prototype. The experimental results show that compared to conventional optics-based autofocusing microscopes, the proposed microscope achieves a more rapid response with no reduction in the focusing accuracy. Consequently, the proposed microscope represents another solution for both existing and emerging industrial applications of automated vision inspection.

  12. 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 seminars,…

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. Orientations to Reflective Practice.

    ERIC Educational Resources Information Center

    Wellington, Bud; Austin, Patricia

    1996-01-01

    Delineates five orientations to reflective practice: immediate, technical, deliberative, dialectic, and transpersonal, each reflecting different social science bases and beliefs and values about education. Views them as interactive, interdependent, noncompeting, aspects of reflective practice. (SK)

  19. Detection and diagnosis of oral neoplasia with an optical coherence microscope

    PubMed Central

    Clark, A. L.; Gillenwater, A.; Alizadeh-Naderi, R.; El-Naggar, A. K.; Richards-Kortum, R.

    2009-01-01

    The use of high resolution, in vivo optical imaging may offer a clinically useful adjunct to standard histopathologic techniques. A pilot study was performed to investigate the diagnostic capabilities of optical coherence microscopy (OCM) to discriminate between normal and abnormal oral tissue. Our objective is to determine whether OCM, a technique combining the subcellular resolution of confocal microscopy with the coherence gating and heterodyne detection of optical coherence tomography, has the same ability as confocal microscopy to detect morphological changes present in precancers of the epithelium while providing superior penetration depths. We report our results using OCM to characterize the features of normal and neoplastic oral mucosa excised from 13 subjects. Specifically, we use optical coherence and confocal microscopic images obtained from human oral biopsy specimens at various depths from the mucosal surface to examine the optical properties that distinguish normal and neoplastic oral mucosa. An analysis of penetration depths achieved by the OCM and its associated confocal arm found that the OCM consistently imaged more deeply. Extraction of scattering coefficients from reflected nuclear intensity is successful in nonhyperkeratotic layers and shows differentiation between scattering properties of normal and dysplastic epithelium and invasive cancer. PMID:15568948

  20. 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). PMID:25996548

  1. Robot-assisted microscope for neurosurgery.

    PubMed

    Giorgi, C; Eisenberg, H; Costi, G; Gallo, E; Garibotto, G; Casolino, D S

    1995-01-01

    We describe the implementation of a robotic arm connected to a neurosurgical operative microscope. A force feedback sensor drives the motors of the arm in response to the positioning of the microscope by the surgeon. Computer graphic techniques allow tracking of the current position of the microscope within the volumetric reconstruction of the brain. The integration of the prototype into the neurosurgical operating room is currently being evaluated. Preliminary comments on this experimental phase are offered. PMID:9079441

  2. 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

  3. [Differential diagnosis of panniculitides].

    PubMed

    Böer-Auer, A

    2016-07-01

    Panniculitides are diseases of the subcutaneous tissue with heterogeneous etiology. They may develop consequent to infections, as a reaction to drugs, after thermal injury, as part of autoimmune diseases, in metabolic disorders or due to infectious organisms. The clinical presentation with subcutaneous nodules is often nonspecific. Moreover, the differentiation from vasculitides of medium-sized vessels can be clinically challenging. Microscopic examination of biopsy specimens is of high importance in the differential diagnosis of panniculitides. Histopathologically, panniculitides can be classified according to the predominantly infiltrated area in septal and lobular panniculitides and they can be separated from vasculitides of medium-sized vessels. Diagnostic difficulties arise from inadequate biopsy specimens and from lack of clinicopathological correlation. This article summarizes diagnostic criteria of frequent and clinically important panniculitides. PMID:27226115

  4. 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.

  5. 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.

  6. 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

  7. 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.

  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. 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. PMID:21307411

  10. 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.

  11. Benefits of Reflective Practice

    ERIC Educational Resources Information Center

    Wagner, Kathi

    2006-01-01

    In this article, the author discusses what she was able to learn from an exercise in self-reflection regarding her teaching. She also discusses the advantages of reflection for administrators: First, a reflective practice is data-driven, making it a more valid way to evaluate administrators' knowledge and skills. Second, a reflective practice…

  12. Telescope With Reflecting Baffle

    NASA Technical Reports Server (NTRS)

    Linlor, W. I.

    1985-01-01

    Telescope baffle made from combination of reflecting surfaces. In contrast with previous ellipsoidal reflecting baffles, new baffle reflects skew rays more effectively and easier to construct. For infrared telescopes, reflecting baffles better than absorbing baffles because heat load reduced, and not necessary to contend with insufficiency of infrared absorption exhibited by black coatings.

  13. Scintillator reflective layer coextrusion

    SciTech Connect

    Yun, Jae-Chul; Para, Adam

    2001-01-01

    A polymeric scintillator has a reflective layer adhered to the exterior surface thereof. The reflective layer comprises a reflective pigment and an adhesive binder. The adhesive binder includes polymeric material from which the scintillator is formed. A method of forming the polymeric scintillator having a reflective layer adhered to the exterior surface thereof is also provided. The method includes the steps of (a) extruding an inner core member from a first amount of polymeric scintillator material, and (b) coextruding an outer reflective layer on the exterior surface of the inner core member. The outer reflective layer comprises a reflective pigment and a second amount of the polymeric scintillator material.

  14. Miniature microscope design and construction based on tilted rotationally asymmetric printed lenses

    NASA Astrophysics Data System (ADS)

    Rogers, Jeremy David

    Successful treatment of many types of cancer is improved when early detection is possible. One method of early detection is microscopic inspection of the tissue at risk. Microscopic inspection can be performed by extracting a biopsy and using traditional microscopes, but biopsy is painful and inconvenient which limits its use. An alternative is in vivo microscopy using an endoscope or microendoscopy. This dissertation describes the design, construction, and evaluation of a miniature microscope or microendoscope based on new microfabrication technologies. All components typically found in a traditional bench-top microscope were designed and built on a miniature scale. The objective was comprised of one planoconvex spherical glass lens and three printed microlenses. The printed lenses were patterned using grayscale lithography in a custom engineered photosensitive hybrid sol-gel glass material. Illumination was delivered by high-brightness Light Emitting Diodes (LEDs) via multimode fiber. The design incorporated a custom imaging detector and a Micro-Electrical-Mechanical-Systems (MEMS) actuator for optical sectioning using structured illumination. The opto-mechanical system is designed using a new concept called "zero alignment assembly" in which the lens elements snap into place and are constrained to a precise position with tolerances tighter than the optical tolerances. This scheme requires no post-assembly alignment or adjustment and simplifies system assembly. The miniature microscope was designed to image in several modes including reflectance, fluorescence, and using structured illumination for optical sectioning. A unique optical design incorporated tilted elements to remove ghost images and internal reflections from the image plane. This design enabled microscopic imaging of extremely low reflectance samples like tissue where the "in-focus" component of the object reflects only 0.04% of the illumination. The miniature microscope was built and tested by

  15. Reflectivity, Reflexivity and Situated Reflective Practice

    ERIC Educational Resources Information Center

    Malthouse, Richard; Roffey-Barentsen, Jodi; Watts, Mike

    2014-01-01

    This paper describes an aspect of reflective practice referred to as situated reflective practice. The overarching theory is derived from social theories of structuration and reflexivity. In particular, from Giddens' theory of structuration, which sees social life as an interplay of agency and structure. Discussion of the research reported…

  16. Modeling tumor cell migration: From microscopic to macroscopic models

    NASA Astrophysics Data System (ADS)

    Deroulers, Christophe; Aubert, Marine; Badoual, Mathilde; Grammaticos, Basil

    2009-03-01

    It has been shown experimentally that contact interactions may influence the migration of cancer cells. Previous works have modelized this thanks to stochastic, discrete models (cellular automata) at the cell level. However, for the study of the growth of real-size tumors with several million cells, it is best to use a macroscopic model having the form of a partial differential equation (PDE) for the density of cells. The difficulty is to predict the effect, at the macroscopic scale, of contact interactions that take place at the microscopic scale. To address this, we use a multiscale approach: starting from a very simple, yet experimentally validated, microscopic model of migration with contact interactions, we derive a macroscopic model. We show that a diffusion equation arises, as is often postulated in the field of glioma modeling, but it is nonlinear because of the interactions. We give the explicit dependence of diffusivity on the cell density and on a parameter governing cell-cell interactions. We discuss in detail the conditions of validity of the approximations used in the derivation, and we compare analytic results from our PDE to numerical simulations and to some in vitro experiments. We notice that the family of microscopic models we started from includes as special cases some kinetically constrained models that were introduced for the study of the physics of glasses, supercooled liquids, and jamming systems.

  17. Modelling and Simulation of the Space Mission MICROSCOPE

    NASA Astrophysics Data System (ADS)

    Bremer, Stefanie; List, M.; Selig, H.; Lämmerzahl, C.

    2009-05-01

    The French space mission MICROSCOPE aims at testing the Equivalence Principle (EP) with an accuracy of 10e-15. The payload, which is developed and built by the French institute ONERA consists of two high-precision capacitive differential accelerometers. The detection of the test mass movement and their control is done via a complex electrode system. The German department ZARM is member of the MICROSCOPE performance team. In addition to drop tower tests, mission simulations and the preperation of the mission data evaluation are realised in close cooperation with the French partners CNES, ONERA and OCA. Therefore a comprehensive simulation of the real system including the science signal and all error sources is built for the development and testing of data reduction and data analysis algorithms to extract the EP violation signal. In this context the focus lays on the correct modelling of the environmental disturbances. Currently new effort to study the influence of the solar radiation and the Earth albedo to the MICROSCOPE mission scenario is underway. The actual status of the mission modelling will be presented.

  18. Modelling and simulation of the space mission MICROSCOPE

    NASA Astrophysics Data System (ADS)

    Bremer, Stefanie; List, Meike; Selig, Hanns; Rath, Hans; Dittus, Hansjörg

    2011-01-01

    MICROSCOPE is a French space mission for testing the weak equivalence principle (WEP). The mission goal is the determination of the Eötvös parameter η with an accuracy of 10 -15. The French space agency CNES is responsible for the satellite which is developed and produced within the Myriade series. The satellite's payload T-SAGE (Twin Space Accelerometer for Gravitation Experimentation) is developed and built by the French institute ONERA. It consists of two high-precision capacitive differential accelerometers. One accelerometer is used as reference sensor with two test masses of platinum, the science sensor contains a platinum and a titanium proof mass. The detection of the test mass movement and their control is done via a complex electrode system. As a member of the MICROSCOPE performance team, the German department ZARM will be involved in the data analysis of the MICROSCOPE mission. For this purpose, mission simulations and the preparation of the mission data evaluation in close cooperation with the French partners CNES, ONERA and OCA are realised. The development status of the simulation tool which will represent the complex spacecraft dynamics and all error sources in order to design and test data reduction procedures is presented and some features are discussed in detail.

  19. Modelling and simulation of the space mission MICROSCOPE

    NASA Astrophysics Data System (ADS)

    Bremer, Stefanie; List, Meike; Selig, Hanns; Lämmerzahl, Claus

    2010-01-01

    The French space mission MICROSCOPE aims at testing the weak Equivalence Principle (EP) with an accuracy of 10-15. The payload, which is developed and built by the French institute ONERA consists of two high-precision capacitive differential accelerometers. The detection of the test mass movement and their control is done via a complex electrode system. The German department ZARM is member of the MICROSCOPE performance team. In addition to drop tower tests, mission simulations and the preparation of the mission data evaluation are realized in close cooperation with the French partners CNES, ONERA and OCA. Therefore a comprehensive simulation of the real system including the science signal and all error sources is built for the development and testing of data reduction and data analysis algorithms to extract the EP violation signal. In this context the focus lays on the correct modeling of the environmental disturbances. Currently new effort to study the influence of the solar radiation and the Earth albedo to the MICROSCOPE mission scenario is underway.

  20. 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.

  1. Getting the Most out of the Microscope

    ERIC Educational Resources Information Center

    Price, Fred W.

    1973-01-01

    Discusses some of the misconceptions that students and instructors have regarding the microscope and provides stepwise instructions to enable the biology student to acquire a sound scientific technique for setting up and using the light microscope with minimal expenditure of time and effort. (JR)

  2. Lamp method and apparatus using multiple reflections

    DOEpatents

    MacLennan, D.A.; Turner, B.; Kipling, K.

    1999-05-11

    A method wherein the light in a sulfur or selenium lamp is reflected through the fill a multiplicity of times to convert ultraviolet radiation to visible is disclosed. A light emitting device comprised of an electrodeless envelope which bears a light reflecting covering around a first portion which does not crack due to differential thermal expansion and which has a second portion which comprises a light transmissive aperture. 20 figs.

  3. Lamp method and apparatus using multiple reflections

    DOEpatents

    MacLennan, Donald A.; Turner, Brian; Kipling, Kent

    1999-01-01

    A method wherein the light in a sulfur or selenium lamp is reflected through the fill a multiplicity of times to convert ultraviolet radiation to visible. A light emitting device comprised of an electrodeless envelope which bears a light reflecting covering around a first portion which does not crack due to differential thermal expansion and which has a second portion which comprises a light transmissive aperture.

  4. Effect of LYRM1 knockdown on proliferation, apoptosis, differentiation and mitochondrial function in the P19 cell model of cardiac differentiation in vitro.

    PubMed

    Chen, Yu-Mei; Li, Xing; Song, Gui-Xian; Liu, Ming; Fan, Yi; Wu, Li-Jie; Li, Hua; Zhang, Qi-Jun; Liu, Yao-Qiu; Qian, Ling-Mei

    2016-02-01

    To explore the effects of LYRM1 knockdown on proliferation, apoptosis, differentiation and mitochondrial function in the embryonic carcinoma (P19) cell model of cardiac differentiation. Knockdown of LYRM1 using small interfering RNA (siRNA) was confirmed by quantitative real-time PCR. Cell Counting Kit-8(CCK-8) proliferation assays and cell cycle analysis demonstrated that LYRM1 gene silencing significantly inhibited P19 cell proliferation. Flow cytometry and measurement of their caspase-3 activities revealed that knockdown of LYRM1 increased P19 cell apoptosis. Observation of morphological changes using an inverted microscope and expression analysis of specific differentiation marker genes using quantitative real-time PCR and Western blotting revealed that knockdown of LYRM1 significantly inhibited the differentiation of P19 cells into cardiomyocytes. Furthermore, real-time quantitative PCR applied to detect mitochondrial DNA (mtDNA) copy number implied that there was no significant difference in the LYRM1 knockdown group compared with the control group. Cellular ATP production investigated by luciferase-based luminescence assay was dramatically decreased in differentiated cells transfected with LYRM1 RNAi. Fluorescence microscopy and flow cytometery were used to detect the reactive oxygen species (ROS) and the mitochondrial membrane potential (MMP) showed that the level of ROS was dramatically increased and MMP was obviously decreased in differentiated cells transfected with LYRM1 RNAi. Collectively, knockdown of LYRM1 promoted apoptosis and suppressed proliferation and differentiation in P19 cells. In addition, knockdown of LYRM1 induced mitochondrial impairment in P19 cells during differentiation, which was reflected by decreased ATP synthesis, lower MMP and increased ROS levels. PMID:26759027

  5. Calibration procedures for quantitative multiple wavelengths reflectance microscopy

    NASA Astrophysics Data System (ADS)

    Fedala, Yasmina; Munteanu, Sorin; Kanoufi, Frédéric; Tessier, Gilles; Roger, Jean Paul; Wu, Chang; Amiot, Fabien

    2016-01-01

    In order to characterize surface chemo-mechanical phenomena driving micro-electro-mechanical systems (MEMSs) behavior, it has been previously proposed to use reflected intensity fields obtained from a standard microscope for different illumination wavelengths. Wavelength-dependent and -independent reflectivity fields are obtained from these images, provided the relative reflectance sensitivities ratio can be identified. This contribution focuses on the necessary calibration procedures and mathematical methods allowing for a quantitative conversion from a mechanically induced reflectivity field to a surface rotation field, therefore paving the way for a quantitative mechanical analysis of MEMS under chemical loading.

  6. Quantitative phase tomography by using x-ray microscope with Foucault knife-edge scanning filter

    NASA Astrophysics Data System (ADS)

    Watanabe, Norio; Tsuburaya, Yuji; Shimada, Akihiro; Aoki, Sadao

    2016-01-01

    Quantitative phase tomography was evaluated by using a differential phase microscope with a Foucault knife-edge scanning filter. A 3D x-ray phase image of polystyrene beads was obtained at 5.4 keV. The reconstructed refractive index was fairly good agreement with the Henke's tabulated data.

  7. Scatter of fatigue data owing to material microscopic effects

    NASA Astrophysics Data System (ADS)

    Tang, XueSong

    2014-01-01

    A common phenomenon of fatigue test data reported in the open literature such as S-N curves exhibits the scatter of points for a group of same specimens under the same loading condition. The reason is well known that the microstructure is different from specimen to specimen even in the same group. Specifically, a fatigue failure process is a multi-scale problem so that a fatigue failure model should have the ability to take the microscopic effect into account. A physically-based trans-scale crack model is established and the analytical solution is obtained by coupling the micro- and macro-scale. Obtained is the trans-scale stress intensity factor as well as the trans-scale strain energy density (SED) factor. By taking this trans-scale SEDF as a key controlling parameter for the fatigue crack propagation from micro- to macro-scale, a trans-scale fatigue crack growth model is proposed in this work which can reflect the microscopic effect and scale transition in a fatigue process. The fatigue test data of aluminum alloy LY12 plate specimens is chosen to check the model. Two S-N experimental curves for cyclic stress ratio R=0.02 and R=0.6 are selected. The scattering test data points and two S-N curves for both R=0.02 and R=0.6 are exactly re-produced by application of the proposed model. It is demonstrated that the proposed model is able to reflect the multiscaling effect in a fatigue process. The result also shows that the microscopic effect has a pronounced influence on the fatigue life of specimens.

  8. Scanning Capacitace Microscope/Atomic Force Microscope/Scanning Tunneling Microscope Study of Ion-Implanted Silicon Surfaces

    NASA Astrophysics Data System (ADS)

    Tomiye, Hideto; Kawami, Hiroshi; Izawa, Michiyoshi; Yoshimura, Masamichi; Yao, Takafumi

    1995-06-01

    We have investigated the local electrical properties of ion-implanted Si using a combined scanning capacitance microscope (SCaM)/atomic force microscope (AFM)/scanning tunneling microscope (STM) with special attention paid to the effect of annealing. The STM image shows that the as-implanted area is insulating, while the unimplanted area is conductive, in an unannealed sample. Both STM and SCaM images clearly indicate that the implanted area is conductive with n-type behavior after annealing. However, the unimplanted area did not show p-type behavior but slightly n-type behavior due to the diffusion of P impurities during annealing.

  9. Volumetric retinal fluorescence microscopic imaging with extended depth of field

    NASA Astrophysics Data System (ADS)

    Li, Zengzhuo; Fischer, Andrew; Li, Wei; Li, Guoqiang

    2016-03-01

    Wavefront-engineered microscope with greatly extended depth of field (EDoF) is designed and demonstrated for volumetric imaging with near-diffraction limited optical performance. A bright field infinity-corrected transmissive/reflective light microscope is built with Kohler illumination. A home-made phase mask is placed in between the objective lens and the tube lens for ease of use. General polynomial function is adopted in the design of the phase plate for robustness and custom merit function is used in Zemax for optimization. The resulting EDoF system achieves an engineered point spread function (PSF) that is much less sensitive to object depth variation than conventional systems and therefore 3D volumetric information can be acquired in a single frame with expanded tolerance of defocus. In Zemax simulation for a setup using 32X objective (NA = 0.6), the EDoF is 20μm whereas a conventional one has a DoF of 1.5μm, indicating a 13 times increase. In experiment, a 20X objective lens with NA = 0.4 was used and the corresponding phase plate was designed and fabricated. Retinal fluorescence images of the EDoF microscope using passive adaptive optical phase element illustrate a DoF around 100μm and it is able to recover the volumetric fluorescence images that are almost identical to in-focus images after post processing. The image obtained from the EDoF microscope is also better in resolution and contrast, and the retinal structure is better defined. Hence, due to its high tolerance of defocus and fine restored image quality, EDoF optical systems have promising potential in consumer portable medical imaging devices where user's ability to achieve focus is not optimal, and other medical imaging equipment where achieving best focus is not a necessary.

  10. Understanding reflective practice.

    PubMed

    Nicol, Jacqueline Sian; Dosser, Isabel

    2016-05-01

    The Nursing and Midwifery Council (NMC) requires that nurses and midwives use feedback as an opportunity for reflection and learning, to improve practice. The NMC revalidation process stipulates that practitioners provide examples of how they have achieved this. To reflect in a meaningful way, it is important to understand what is meant by reflection, the skills required, and how reflection can be undertaken successfully. Traditionally, reflection occurs after an event encountered in practice. The authors challenge this perception, suggesting that reflection should be undertaken before, during and after an event. This article provides practical guidance to help practitioners use reflective models to write reflective accounts. It also outlines how the reflective process can be used as a valuable learning tool in preparation for revalidation. PMID:27154119

  11. Reflectivity method for geomechanical equilibria

    NASA Astrophysics Data System (ADS)

    Kuvshinov, Boris N.

    2007-08-01

    It is shown that the block LU decomposition of the transfer and scattering matrix convert these matrices into each other. This allows to introduce a generalization of the Kennett reflectivity method, which is applicable to arbitrary systems of linear differential equations. The introduced method is convenient to analyse equilibria, where the governing matrix is degenerate. The resulting algorithm is compact and numerically stable. To illustrate the concept, we consider elastic equilibrium of a layered medium. We also derive closed-form expressions for a quasi-stationary poroelastic case taking into account solid-fluid and electrokinetic coupling.

  12. Quantitative reflection imaging of fixed Aplysia californica pedal ganglion neurons on nanostructured plasmonic crystals.

    PubMed

    Le, An-Phong; Kang, Somi; Thompson, Lucas B; Rubakhin, Stanislav S; Sweedler, Jonathan V; Rogers, John A; Nuzzo, Ralph G

    2013-10-24

    Studies of the interactions between cells and surrounding environment including cell culture surfaces and their responses to distinct chemical and physical cues are essential to understanding the regulation of cell growth, migration, and differentiation. In this work, we demonstrate the capability of a label-free optical imaging technique-surface plasmon resonance (SPR)-to quantitatively investigate the relative thickness of complex biomolecular structures using a nanoimprinted plasmonic crystal and laboratory microscope. Polyelectrolyte films of different thicknesses deposited by layer-by-layer assembly served as the model system to calibrate the reflection contrast response originating from SPRs. The calibrated SPR system allows quantitative analysis of the thicknesses of the interface formed between the cell culture substrate and cellular membrane regions of fixed Aplysia californica pedal ganglion neurons. Bandpass filters were used to isolate spectral regions of reflected light with distinctive image contrast changes. Combining of the data from images acquired using different bandpass filters leads to increase image contrast and sensitivity to topological differences in interface thicknesses. This SPR-based imaging technique is restricted in measurable thickness range (∼100-200 nm) due to the limited plasmonic sensing volume, but we complement this technique with an interferometric analysis method. Described here simple reflection imaging techniques show promise as quantitative methods for analyzing surface thicknesses at nanometer scale over large areas in real-time and in physicochemical diverse environments. PMID:23647567

  13. 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

  14. Reflections in art

    PubMed Central

    CAVANAGH, PATRICK; CHAO, JESSICA; WANG, DINA

    2009-01-01

    When artists depict a mirror in a painting, it necessarily lacks the most obvious property of a mirror: as we move around the painting of the mirror, the reflections we see in it do not change. And yet representations of mirrors and other reflecting surfaces can be quite convincing in paintings. Here, we will examine the rules of reflection, the many ways that painters can break those rules without losing the impression of reflection and the rules that cannot be broken. The rules that govern the perception of reflection are a small subset of the physical rules of reflection. PMID:18534102

  15. 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.

  16. 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.

  17. 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.

  18. 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. PMID:7012367

  19. 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.

  20. 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.

  1. 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.

  2. Recent Opportunity Microscopic Imager Results

    NASA Astrophysics Data System (ADS)

    Herkenhoff, K. E.; Arvidson, R. E.; Jolliff, B. L.; Yingst, R.; Team, A.

    2013-12-01

    Opportunity arrived at exposures of Endeavour crater rim rocks in August 2011, on a hill dubbed 'Cape York.' These rocks have been the goal of exploration by Opportunity for the past few years because spectral evidence for phyllosilicates was observed at this location in orbital remote sensing data. As Opportunity circum¬navigated Cape York, the Microscopic Imager (MI) was used to examine the fine-scale textures of various soils and rocky outcrops. As reported previously, Opportunity discovered multiple bright linear features along the western periphery of Cape York that have been interpreted as veins of Ca sulfate deposited in fractures within the bedrock of Cape York. Opportunity then explored the northern and eastern sides of Cape York, including the area around 'Matijevic Hill' that shows evidence for phyllosilicates in CRISM data acquired from the Mars Reconnaissance Orbiter. One of the first outcrops examined near Matijevic Hill, dubbed 'Kirkwood,' is dominated by millimeter-size spherules. Unlike the hematite-rich concretions observed by Opportunity on Meridiani Planum, the aggregated 'newberries' in the Kirkwood exposure display internal structure and resistant rims. Compositionally, the spherule-rich rock is very similar to a nearby spherule-poor outcrop dubbed 'Whitewater Lake.' Thus these spherules have a more basalt-like composition compared to the hematite-rich concretions of the Burns Formation. The origin of the Kirkwood outcrop is uncertain, but the setting on the rim of the 22-km diameter Endeavour crater suggests that perhaps impact melting was involved in lapilli formation, possibly followed by mobilization and sorting in the ejecta blanket. Alternatively, the newberries may be diagenetic iron oxide concretions that are less well cemented than the 'blueberries' of the younger sulfate-rich Burns Formation. The Whitewater Lake outcrops contain the phyllosilicate phases observed from orbit, and are the oldest materials yet investigated by

  3. Neutron reflecting supermirror structure

    DOEpatents

    Wood, James L.

    1992-01-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources.

  4. Neutron reflecting supermirror structure

    DOEpatents

    Wood, J.L.

    1992-12-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. 2 figs.

  5. Reflective Learning in Practice.

    ERIC Educational Resources Information Center

    Brockbank, Anne, Ed.; McGill, Ian, Ed.; Beech, Nic, Ed.

    This book contains 22 papers on reflective learning in practice. The following papers are included: "Our Purpose" (Ann Brockbank, Ian McGill, Nic Beech); "The Nature and Context of Learning" (Ann Brockbank, Ian McGill, Nic Beech); "Reflective Learning and Organizations" (Ann Brockbank, Ian McGill, Nic Beech); "Reflective Learning in Practice" (Ann…

  6. Liberating Moral Reflection

    ERIC Educational Resources Information Center

    Horell, Harold D.

    2013-01-01

    The author argues that if we are to foster life-giving and liberating moral reflection, we must first liberate moral reflection from distortions; specifically, from the distorting effects of moral insensitivity, destructive moral relativism, and confusions resulting from a failure to understand the dynamics of moral reflection. The author proposes…

  7. Teaching Critical Reflection

    ERIC Educational Resources Information Center

    Smith, Elizabeth

    2011-01-01

    Despite long-standing commitment to the notion of critical reflection across the healthcare professions it is unusual for critical theory and practice to be taught as explicit subjects in healthcare higher education. There is evidence to show that reflective techniques such as critical portfolios and reflective diaries can help students to…

  8. A pragmatic guide to multiphoton microscope design

    PubMed Central

    Young, Michael D.; Field, Jeffrey J.; Sheetz, Kraig E.; Bartels, Randy A.; Squier, Jeff

    2016-01-01

    Multiphoton microscopy has emerged as a ubiquitous tool for studying microscopic structure and function across a broad range of disciplines. As such, the intent of this paper is to present a comprehensive resource for the construction and performance evaluation of a multiphoton microscope that will be understandable to the broad range of scientific fields that presently exploit, or wish to begin exploiting, this powerful technology. With this in mind, we have developed a guide to aid in the design of a multiphoton microscope. We discuss source selection, optical management of dispersion, image-relay systems with scan optics, objective-lens selection, single-element light-collection theory, photon-counting detection, image rendering, and finally, an illustrated guide for building an example microscope. PMID:27182429

  9. Feedback regulation of microscopes by image processing.

    PubMed

    Tsukada, Yuki; Hashimoto, Koichi

    2013-05-01

    Computational microscope systems are becoming a major part of imaging biological phenomena, and the development of such systems requires the design of automated regulation of microscopes. An important aspect of automated regulation is feedback regulation, which is the focus of this review. As modern microscope systems become more complex, often with many independent components that must work together, computer control is inevitable since the exact orchestration of parameters and timings for these multiple components is critical to acquire proper images. A number of techniques have been developed for biological imaging to accomplish this. Here, we summarize the basics of computational microscopy for the purpose of building automatically regulated microscopes focus on feedback regulation by image processing. These techniques allow high throughput data acquisition while monitoring both short- and long-term dynamic phenomena, which cannot be achieved without an automated system. PMID:23594233

  10. Microscope for high-temperature welding

    NASA Technical Reports Server (NTRS)

    Accountius, O. E.

    1980-01-01

    Dark glass in eyepieces lets welder look at fine parts without eye damage. Previously welder had to repair barely visible crack without magnification, because necessary goggles kept eyes too far from microscope eyepieces.

  11. A Live Specimen Cell for the Microscope.

    ERIC Educational Resources Information Center

    McNeil, D. W.

    1991-01-01

    Provides background and instructions for the assembly of a microaquarium, or specimen cell, in which the dynamic world of living microorganisms can be viewed through a microscope overextended periods of time utilizing the simplest of materials in the process. (JJK)

  12. Marcello Malpighi: the father of microscopic anatomy.

    PubMed

    DiDio, L J

    1995-01-01

    Biographical data of Malpighi to justify naming him "the father of microscopic anatomy", as he used the microscope, soon after its invention, to study and discover and accurately describe many biological, particularly anatomical, structures. Although he utilized the microscope as a scientific instrument, his ideas, innovations and discoveries caused such an opposition that the microscope could be considered as Malpighi's weapon to start a scientific revolution. He was a naturalist for whom the "natural world, known and experienced scientifically, was all that existed". He was also a "cardiocentrist", who opposed Galen's "hepatocentrism". Several anatomical structures known eponymically to honor Malpighi are listed followed by their synonyms. Malpighi is another example of a genius as an extraordinary man who stood on the shoulders of giants, such as Galilei, Hans and Zacharias Janssen, Borelli, Harvey, B. Massari, among others. PMID:11322304

  13. Differentiated Staffing.

    ERIC Educational Resources Information Center

    Scobey, Mary-Margaret, Ed.; Fiorino, A. John, Ed.

    This book is a collection of six articles that deal with the concept and the practice of differentiated staffing in education. Included in the collection are articles on the concept itself; on problems, prospects, and the practical implementation of the concept; staff differentiation in a multiunit school; and polemical aspects of differentiated…

  14. Differential games.

    NASA Technical Reports Server (NTRS)

    Varaiya, P. P.

    1972-01-01

    General discussion of the theory of differential games with two players and zero sum. Games starting at a fixed initial state and ending at a fixed final time are analyzed. Strategies for the games are defined. The existence of saddle values and saddle points is considered. A stochastic version of a differential game is used to examine the synthesis problem.

  15. Microscopic thermoelastic characterizations by interferometric photothermal microscopy

    NASA Astrophysics Data System (ADS)

    Jumel, Julien; Lepoutre, François; Rochais, Denis; Enguehard, Franck

    2003-01-01

    Some publications have demonstrated that local thermoelastic behavior in materials can be revealed using a photothermal microscope coupled with an interferometer, but up to now the quantitative data that can be extracted from these measures are not established clearly. We present analysis of the signals, numerical simulations, and experimental results which demonstrate that the thermal diffusivity, the elastic anisotropy, and the principal directions of anisotropy orientation can be obtained with a microscopic resolution.

  16. {sup 4}He microscopic optical model potential

    SciTech Connect

    Guo Hairui; Liang Haiying; Han Yinlu; Shen Qingbiao; Xu Yongli

    2011-06-15

    The {sup 4}He microscopic optical model potential is obtained by Green's function method through nuclear matter approximation and local density approximation based on the effective Skyrme interaction. The microscopic optical model potential is analyzed and utilized to calculate the reaction cross sections and elastic scattering angular distributions for the target nuclei in the mass range 12{<=}A{<=}209 with incident {sup 4}He energy up to 400 MeV. The theoretical results are compared with the experimental data.

  17. Microscopic polyangiitis presenting with hemorrhagic stroke.

    PubMed

    Iglesias, Estíbaliz; Eleftheriou, Despina; Mankad, Kshitij; Prabhakar, Prab; Brogan, Paul A

    2014-08-01

    Microscopic polyangiitis associated with antineutrophil cytoplasmic antibodies directed against myeloperoxidase rarely affects the central nervous system, and this is common in the presence of other organ involvement. The authors report the case of a 12-year-old girl who presented with multiple acute parieto-occipital hematomas as the only manifestation of presumed microscopic polyangiitis. Early treatment with immunosuppression resulted in complete recovery and a favorable outcome. PMID:23690295

  18. Revalidation and reflective practice.

    PubMed

    Finch, Alison

    2016-04-01

    From April 2016 nurses must meet the requirements of the new Nursing and Midwifery Council (NMC) revalidation process to maintain their registration. It is their responsibility to ensure they meet all revalidation requirements, but organisations and nurse leaders can support them to do so. Reflection is an important part of revalidation, and nurses are required to submit written reflective accounts and engage in reflective discussion. This article discusses how revalidation encourages a more conscious and active form of reflection. It also describes how leaders can help nurses to reflect on practice to identify improvements and become more familiar with the NMC Code. PMID:27032284

  19. Soft x-ray laser microscope

    SciTech Connect

    Suckewer, P.I.

    1990-10-01

    The program consisted of two phases (Phase I and Phase II). The goal of the Phase I (first year program) was to design and construct the Soft X-ray Laser Contact Microscope. Such microscope was constructed and adapted to PPL's 18.2nm soft X-ray Laser (SXL), which in turn was modified and prepared for microscopy experiments. Investigation of the photoresist response to 18.2nm laser radiation and transmissivity of 0.1m thick silicion-nitride (Si[sub 3]N[sub 4]) windows were important initial works. The goal of the first year of Phase II was to construct X-ray contact microscope in combination with existing optical phase microscope, already used by biologists. In the second year of Phase II study of dehydrated Horeseshoe Crab and Hela cancer cells were performed with COXRALM. Also during Phase II, the Imaging X-Ray Laser Microscope (IXRALM) was designed and constructed. This paper describes the development of each of the microscopes and their application for research.

  20. IMIS: An intelligence microscope imaging system

    NASA Technical Reports Server (NTRS)

    Caputo, Michael; Hunter, Norwood; Taylor, Gerald

    1994-01-01

    Until recently microscope users in space relied on traditional microscopy techniques that required manual operation of the microscope and recording of observations in the form of written notes, drawings, or photographs. This method was time consuming and required the return of film and drawings from space for analysis. No real-time data analysis was possible. Advances in digital and video technologies along with recent developments in article intelligence will allow future space microscopists to have a choice of three additional modes of microscopy: remote coaching, remote control, and automation. Remote coaching requires manual operations of the microscope with instructions given by two-way audio/video transmission during critical phases of the experiment. When using the remote mode of microscopy, the Principal Investigator controls the microscope from the ground. The automated mode employs artificial intelligence to control microscope functions and is the only mode that can be operated in the other three modes as well. The purpose of this presentation is to discuss the advantages and disadvantages of the four modes of of microscopy and how the IMIS, a proposed intelligent microscope imaging system, can be used as a model for developing and testing concepts, operating procedures, and equipment design of specifications required to provide a comprehensive microscopy/imaging capability onboard Space Station Freedom.

  1. X-ray laser microscope apparatus

    DOEpatents

    Suckewer, Szymon; DiCicco, Darrell S.; Hirschberg, Joseph G.; Meixler, Lewis D.; Sathre, Robert; Skinner, Charles H.

    1990-01-01

    A microscope consisting of an x-ray contact microscope and an optical microscope. The optical, phase contrast, microscope is used to align a target with respect to a source of soft x-rays. The source of soft x-rays preferably comprises an x-ray laser but could comprise a synchrotron or other pulse source of x-rays. Transparent resist material is used to support the target. The optical microscope is located on the opposite side of the transparent resist material from the target and is employed to align the target with respect to the anticipated soft x-ray laser beam. After alignment with the use of the optical microscope, the target is exposed to the soft x-ray laser beam. The x-ray sensitive transparent resist material whose chemical bonds are altered by the x-ray beam passing through the target mater GOVERNMENT LICENSE RIGHTS This invention was made with government support under Contract No. De-FG02-86ER13609 awarded by the Department of Energy. The Government has certain rights in this invention.

  2. A differential staining technique for vertebrate histology.

    PubMed

    Bhattacharyya, T K

    1979-03-01

    A staining method is described for studying micro-anatomy of different vertebrate tissues in the light microscope. A staining sequence of celestin blue--erythrosin--orange G--fast green with mordanting in phosphomolybdic acid yields a satisfactory differentiation and fine colour contrast in various tissues. The efficacy of the method was tested on different avian and mammalian tissues. PMID:86938

  3. Three-dimensional in vivo imaging by a handheld dual-axes confocal microscope

    PubMed Central

    Ra, Hyejun; Piyawattanametha, Wibool; Mandella, Michael J.; Hsiung, Pei-Lin; Hardy, Jonathan; Wang, Thomas D.; Contag, Christopher H.; Kino, Gordon S.; Solgaard, Olav

    2008-01-01

    We present a handheld dual-axes confocal microscope that is based on a two-dimensional microelectromechanical systems (MEMS) scanner. It performs reflectance and fluorescence imaging at 488 nm wavelength, with three-dimensional imaging capability. The fully packaged microscope has a diameter of 10 mm and acquires images at 4 Hz frame rate with a maximum field of view of 400 μm × 260 μm. The transverse and axial resolutions of the handheld probe are 1.7 μm and 5.8 μm, respectively. Capability to perform real time small animal imaging is demonstrated in vivo in transgenic mice. PMID:18545427

  4. Microwave-Assisted Switching of Microscopic Rings: Correlation Between Nonlinear Spin Dynamics and Critical Microwave Fields

    NASA Astrophysics Data System (ADS)

    Podbielski, Jan; Heitmann, Detlef; Grundler, Dirk

    2007-11-01

    We have studied the spin dynamics of microscopic permalloy rings at GHz frequencies. Increasing the irradiation power, we observe first nonlinear spin dynamics and second microwave-assisted switching (MAS). We explore the MAS phase diagram as a function of microwave power and frequency f and, in particular, extract the critical microwave field hc(f). Its frequency dependence reflects characteristic eigenfrequencies from both the linear and nonlinear spin-wave spectrum. By comparing hc(f) with the different susceptibilities, we gain insight into the microscopic processes which might be the basis of a predictive theory of MAS.

  5. Reflective and refractive objects for mixed reality.

    PubMed

    Knecht, Martin; Traxler, Christoph; Winklhofer, Christoph; Wimmer, Michael

    2013-04-01

    In this paper, we present a novel rendering method which integrates reflective or refractive objects into a differential instant radiosity (DIR) framework usable for mixed-reality (MR) applications. This kind of objects are very special from the light interaction point of view, as they reflect and refract incident rays. Therefore they may cause high-frequency lighting effects known as caustics. Using instant-radiosity (IR) methods to approximate these high-frequency lighting effects would require a large amount of virtual point lights (VPLs) and is therefore not desirable due to real-time constraints. Instead, our approach combines differential instant radiosity with three other methods. One method handles more accurate reflections compared to simple cubemaps by using impostors. Another method is able to calculate two refractions in real-time, and the third method uses small quads to create caustic effects. Our proposed method replaces parts in light paths that belong to reflective or refractive objects using these three methods and thus tightly integrates into DIR. In contrast to previous methods which introduce reflective or refractive objects into MR scenarios, our method produces caustics that also emit additional indirect light. The method runs at real-time frame rates, and the results show that reflective and refractive objects with caustics improve the overall impression for MR scenarios. PMID:23428441

  6. Differential interference contrast tomography.

    PubMed

    Vishnyakov, Gennady; Levin, Gennady; Minaev, Vladimir; Latushko, Mikhail; Nekrasov, Nikolay; Pickalov, Valery

    2016-07-01

    We present a new approach to optical tomography of phase objects that is referred to as differential interference contrast tomography (DICT). The main feature of DICT is that the result of tomographic reconstruction is a 3D DIC image. This image is described by partial derivative of 3D refractive index distribution in one direction. The DICT setup consists of a lateral shearing phase-shifting interference microscope with low-coherent LED illumination. To create projections of the sample at various illumination angles, an angular scanning beam was used. 3D DIC tomograms of a white blood cell are presented. The comparison between the reconstructed DIC tomogram slices and the conventional DIC images of the same sample at the same depths are also represented. PMID:27367095

  7. Microscopic analysis of (p, n) and (p, p) scattering on the tin isotopes

    SciTech Connect

    Ning Pingzhi

    1987-07-01

    Microscopic calculations are performed for the (p, n) charge-exchange reaction and (p, p) elastic scattering on WSn and SUSn at a proton energy of 24.5 MeV. The optical potentials and the isospin-coupling potential are generated from a density-dependent complex effective nucleon-nucleon interaction and the nucleon density distributions of the target nucleus. The (p, n) and (p, p) differential cross sections are calculated simultaneously by solving the coupled Lane equations exactly. The results of these microscopic calculations yield reasonable agreement with the measured values, even though they contain no adjustable parameters.

  8. Designs for a quantum electron microscope.

    PubMed

    Kruit, P; Hobbs, R G; Kim, C-S; Yang, Y; Manfrinato, V R; Hammer, J; Thomas, S; Weber, P; Klopfer, B; Kohstall, C; Juffmann, T; Kasevich, M A; Hommelhoff, P; Berggren, K K

    2016-05-01

    One of the astounding consequences of quantum mechanics is that it allows the detection of a target using an incident probe, with only a low probability of interaction of the probe and the target. This 'quantum weirdness' could be applied in the field of electron microscopy to generate images of beam-sensitive specimens with substantially reduced damage to the specimen. A reduction of beam-induced damage to specimens is especially of great importance if it can enable imaging of biological specimens with atomic resolution. Following a recent suggestion that interaction-free measurements are possible with electrons, we now analyze the difficulties of actually building an atomic resolution interaction-free electron microscope, or "quantum electron microscope". A quantum electron microscope would require a number of unique components not found in conventional transmission electron microscopes. These components include a coherent electron beam-splitter or two-state-coupler, and a resonator structure to allow each electron to interrogate the specimen multiple times, thus supporting high success probabilities for interaction-free detection of the specimen. Different system designs are presented here, which are based on four different choices of two-state-couplers: a thin crystal, a grating mirror, a standing light wave and an electro-dynamical pseudopotential. Challenges for the detailed electron optical design are identified as future directions for development. While it is concluded that it should be possible to build an atomic resolution quantum electron microscope, we have also identified a number of hurdles to the development of such a microscope and further theoretical investigations that will be required to enable a complete interpretation of the images produced by such a microscope. PMID:26998703

  9. First Atomic Force Microscope Image from Mars

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This calibration image presents three-dimensional data from the atomic force microscope on NASA's Phoenix Mars Lander, showing surface details of a substrate on the microscope station's sample wheel. It will be used as an aid for interpreting later images that will show shapes of minuscule Martian soil particles.

    The area imaged by the microscope is 40 microns by 40 microns, small enough to fit on an eyelash. The grooves in this substrate are 14 microns (0.00055 inch) apart, from center to center. The vertical dimension is exaggerated in the image to make surface details more visible. The grooves are 300 nanometers (0.00001 inch) deep.

    This is the first atomic force microscope image recorded on another planet. It was taken on July 9, 2008, during the 44th Martian day, or sol, of the Phoenix mission since landing.

    Phoenix's Swiss-made atomic force microscope builds an image of the surface shape of a particle by sensing it with a sharp tip at the end of a spring, all microfabricated out of a silicon wafer. A strain gauge records how far the spring flexes to follow the contour of the surface. It can provide details of soil-particle shapes smaller than one-hundredth the width of a human hair. This is about 20 times smaller than what can be resolved with Phoenix's optical microscope, which has provided much higher-magnification imaging than anything seen on Mars previously. Both microscopes are part of Phoenix's Microscopy, Electrochemistry and Conductivity Analyzer.

  10. Differential Spectroscopic Imaging of Particulate Explosives Residue

    SciTech Connect

    Bernacki, Bruce E.; Ho, Nicolas

    2008-04-01

    We present experimental results showing transmission and reflection imaging of approximately 100 microgram quantities of particulate explosives residue using a commercial uncooled microbolometer infrared camera and CO2 laser differential wavelength illumination.

  11. DIFFERENTIAL ANALYZER

    DOEpatents

    Sorensen, E.G.; Gordon, C.M.

    1959-02-10

    Improvements in analog eomputing machines of the class capable of evaluating differential equations, commonly termed differential analyzers, are described. In general form, the analyzer embodies a plurality of basic computer mechanisms for performing integration, multiplication, and addition, and means for directing the result of any one operation to another computer mechanism performing a further operation. In the device, numerical quantities are represented by the rotation of shafts, or the electrical equivalent of shafts.

  12. Geometrical design for aspheric reflecting systems.

    PubMed

    Mertz, L

    1979-12-15

    Two separate geometric design procedures are presented for calculating aspheric surfaces. The first calculates individual reflecting surfaces for correcting the optical path length (OPL) of a system. The second jointly calculates pairs of surfaces for the simultaneous correction of OPL and offense against the sine condition (OCS). The procedures remain valid for extreme focal ratios. Applications of these procedures are made to the design of Arecibo-style (stationary spherical primary) telescopes, coma-correctors for such telescopes, three-mirror aplanats with deep spherical primaries, and two-mirror aplanats. Unusual new forms of aplanatic telescope and microscope objectives have emerged from these applications. PMID:20216777

  13. Reflective diffraction grating

    DOEpatents

    Lamartine, Bruce C.

    2003-06-24

    Reflective diffraction grating. A focused ion beam (FIB) micromilling apparatus is used to store color images in a durable medium by milling away portions of the surface of the medium to produce a reflective diffraction grating with blazed pits. The images are retrieved by exposing the surface of the grating to polychromatic light from a particular incident bearing and observing the light reflected by the surface from specified reception bearing.

  14. Tandem resonator reflectance modulator

    DOEpatents

    Fritz, Ian J.; Wendt, Joel R.

    1994-01-01

    A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and light reflecting from the inner mirror is out of phase with light from the outer mirrors.

  15. Tandem resonator reflectance modulator

    DOEpatents

    Fritz, I.J.; Wendt, J.R.

    1994-09-06

    A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and light reflecting from the inner mirror is out of phase with light from the outer mirrors. 8 figs.

  16. Optical modeling of Fresnel zoneplate microscopes.

    PubMed

    Naulleau, Patrick P; Mochi, Iacopo; Goldberg, Kenneth A

    2011-07-10

    Defect free masks remain one of the most significant challenges facing the commercialization of extreme ultraviolet (EUV) lithography. Progress on this front requires high-performance wavelength-specific metrology of EUV masks, including high-resolution and aerial-image microscopy performed near the 13.5 nm wavelength. Arguably the most cost-effective and rapid path to proliferating this capability is through the development of Fresnel zoneplate-based microscopes. Given the relative obscurity of such systems, however, modeling tools are not necessarily optimized to deal with them and their imaging properties are poorly understood. Here we present a modeling methodology to analyze zoneplate microscopes based on commercially available optical modeling software and use the technique to investigate the imaging performance of an off-axis EUV microscope design. The modeling predicts that superior performance can be achieved by tilting the zoneplate, making it perpendicular to the chief ray at the center of the field, while designing the zoneplate to explicitly work in that tilted plane. Although the examples presented here are in the realm of EUV mask inspection, the methods described and analysis results are broadly applicable to zoneplate microscopes in general, including full-field soft-x-ray microscopes routinely used in the synchrotron community. PMID:21743581

  17. Microscopic fungi as significant sesquiterpene emission sources

    NASA Astrophysics Data System (ADS)

    HorváTh, Eszter; Hoffer, AndráS.; SebőK, Flóra; Dobolyi, Csaba; Szoboszlay, SáNdor; Kriszt, BaláZs; GelencséR, AndráS.

    2011-08-01

    Among the volatile organic compounds emitted by vegetation, isoprene, monoterpenes, sesquiterpenes, and their derivatives are thought to contribute to secondary organic aerosol formation. Although it is well known that microscopic fungi globally turn over vast amount of carbon by decomposing the organic matter in the soil, vegetation is considered as the exclusive source of biogenic secondary organic aerosol precursors in various atmospheric models. Secondary fungal metabolites including sesquiterpenes have been recognized as characteristic volatile organic compounds emitted by fungi. In the present study, we investigated the rates of sesquiterpene emission of microscopic fungi to establish their potential significance compared to those from vegetation. To sample the headspace of the pure culture of some common fungi, we used an aseptic flow-through apparatus designed for solid phase microextraction in our laboratory. The identified sesquiterpenes in the headspace extracts were quantified for eight strains of microscopic fungi belonging to four different genera. Our results showed that microscopic fungi emit a considerable amount of sesquiterpenes. Based on our first estimations microscopic fungi may be considered as potentially significant sesquiterpene emission sources whose contribution to secondary organic aerosol formation may be comparable to that of vegetation.

  18. Microscopic features of moving traffic jams

    NASA Astrophysics Data System (ADS)

    Kerner, Boris S.; Klenov, Sergey L.; Hiller, Andreas; Rehborn, Hubert

    2006-04-01

    Empirical and numerical microscopic features of moving traffic jams are presented. Based on a single vehicle data analysis, it is found that within wide moving jams, i.e., between the upstream and downstream jam fronts there is a complex microscopic spatiotemporal structure. This jam structure consists of alternations of regions in which traffic flow is interrupted and flow states of low speeds associated with “moving blanks” within the jam. Moving blanks within a wide moving jam resemble electron holes in the valence band of semiconductors: As the moving blanks that propagate upstream appear due to downstream vehicle motion within the jam, so appearance of electron holes moving with the electric field results from electron motion against the electric field in the valence band of semiconductors. Empirical features of moving blanks are found. Based on microscopic models in the context of the Kerner’s three-phase traffic theory, physical reasons for moving blanks emergence within wide moving jams are disclosed. Microscopic nonlinear effects of moving jam emergence, propagation, and dissolution as well as a diverse variety of hysteresis effects in freeway traffic associated with phase transitions and congested traffic propagation are numerically investigated. Microscopic structure of moving jam fronts is numerically studied and compared with empirical results.

  19. Optical modeling of Fresnel zoneplate microscopes

    SciTech Connect

    Naulleau, Patrick P.; Mochi, Iacopo; Goldberg, Kenneth A.

    2011-07-10

    Defect free masks remain one of the most significant challenges facing the commercialization of extreme ultraviolet (EUV) lithography. Progress on this front requires high-performance wavelength-specific metrology of EUV masks, including high-resolution and aerial-image microscopy performed near the 13.5 nm wavelength. Arguably the most cost-effective and rapid path to proliferating this capability is through the development of Fresnel zoneplate-based microscopes. Given the relative obscurity of such systems, however, modeling tools are not necessarily optimized to deal with them and their imaging properties are poorly understood. Here we present a modeling methodology to analyze zoneplate microscopes based on commercially available optical modeling software and use the technique to investigate the imaging performance of an off-axis EUV microscope design. The modeling predicts that superior performance can be achieved by tilting the zoneplate, making it perpendicular to the chief ray at the center of the field, while designing the zoneplate to explicitly work in that tilted plane. Although the examples presented here are in the realm of EUV mask inspection, the methods described and analysis results are broadly applicable to zoneplate microscopes in general, including full-field soft-x-ray microscopes routinely used in the synchrotron community.

  20. Optical modeling of Fresnel zoneplate microscopes

    SciTech Connect

    Naulleau, Patrick; Mochi, Iacopo; Goldberg, Kenneth A.

    2011-04-06

    Defect free masks remain one of the most significant challenges facing the commercialization of extreme ultraviolet (EUV) lithography. Progress on this front requires high-performance wavelength-specific metrology of EUV masks, including high-resolution and aerial-image microscopy performed near the 13.5 nm wavelength. Arguably the most cost-effective and rapid path to proliferating this capability is through the development of Fresnel zoneplate-based microscopes. Given the relative obscurity of such systems, however, modeling tools are not necessarily optimized to deal with them and their imaging properties are poorly understood. Here we present a modeling methodology to analyze zoneplate microscopes based on commercially available optical modeling software and use the technique to investigate the imaging performance of an off-axis EUV microscope design. The modeling predicts that superior performance can be achieved by tilting the zoneplate, making it perpendicular to the chief ray at the center of the field, while designing the zoneplate to explicitly work in that tilted plane. Although the examples presented here are in the realm of EUV mask inspection, the methods described and analysis results are broadly applicable to zoneplate microscopes in general, including full-field soft-x-ray microscopes rou tinely used in the synchrotron community.

  1. Miniaturized integration of a fluorescence microscope

    PubMed Central

    Ghosh, Kunal K.; Burns, Laurie D.; Cocker, Eric D.; Nimmerjahn, Axel; Ziv, Yaniv; Gamal, Abbas El; Schnitzer, Mark J.

    2013-01-01

    The light microscope is traditionally an instrument of substantial size and expense. Its miniaturized integration would enable many new applications based on mass-producible, tiny microscopes. Key prospective usages include brain imaging in behaving animals towards relating cellular dynamics to animal behavior. Here we introduce a miniature (1.9 g) integrated fluorescence microscope made from mass-producible parts, including semiconductor light source and sensor. This device enables high-speed cellular-level imaging across ∼0.5 mm2 areas in active mice. This capability allowed concurrent tracking of Ca2+ spiking in >200 Purkinje neurons across nine cerebellar microzones. During mouse locomotion, individual microzones exhibited large-scale, synchronized Ca2+ spiking. This is a mesoscopic neural dynamic missed by prior techniques for studying the brain at other length scales. Overall, the integrated microscope is a potentially transformative technology that permits distribution to many animals and enables diverse usages, such as portable diagnostics or microscope arrays for large-scale screens. PMID:21909102

  2. Microscopic oxygen imaging based on fluorescein bleaching efficiency measurements.

    PubMed

    Beutler, Martin; Heisterkamp, Ines M; Piltz, Bastian; Stief, Peter; De Beer, Dirk

    2014-05-01

    Photobleaching of the fluorophore fluorescein in an aqueous solution is dependent on the oxygen concentration. Therefore, the time-dependent bleaching behavior can be used to measure of dissolved oxygen concentrations. The method can be combined with epi-fluorescence microscopy. The molecular states of the fluorophore can be expressed by a three-state energy model. This leads to a set of differential equations which describe the photobleaching behavior of fluorescein. The numerical solution of these equations shows that in a conventional wide-field fluorescence microscope, the fluorescence of fluorescein will fade out faster at low than at high oxygen concentration. Further simulation showed that a simple ratio function of different time-points during a fluorescence decay recorded during photobleaching could be used to describe oxygen concentrations in an aqueous solution. By careful choice of dye concentration and excitation light intensity the sensitivity in the oxygen concentration range of interest can be optimized. In the simulations, the estimation of oxygen concentration by the ratio function was very little affected by the pH value in the range of pH 6.5-8.5. Filming the fluorescence decay by a charge-coupled-device (ccd) camera mounted on a fluorescence microscope allowed a pixelwise estimation of the ratio function in a microscopic image. Use of a microsensor and oxygen-consuming bacteria in a sample chamber enabled the calibration of the system for quantification of absolute oxygen concentrations. The method was demonstrated on nitrifying biofilms growing on snail and mussel shells, showing clear effects of metabolic activity on oxygen concentrations. PMID:24610786

  3. Neutron reflecting supermirror structure

    DOEpatents

    Wood, James L.

    1992-01-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. One layer of each set of bilayers consist of titanium, and the second layer of each set of bilayers consist of an alloy of nickel with carbon interstitially present in the nickel alloy.

  4. Light- and electron-microscopic histochemistry of Fabry's disease.

    PubMed Central

    Faraggiana, T.; Churg, J.; Grishman, E.; Strauss, L.; Prado, A.; Bishop, D. F.; Schuchman, E.; Desnick, R. J.

    1981-01-01

    A histochemical study was performed on light- and electron-microscopic level in a case of Fabry's disease. The patient underwent kidney transplantation for renal failure and died of heart failure 6 months later. Patient's tissues were studied at the light- and electron-microscopic levels with various embedding and staining techniques for lipids and carbohydrates. Two peroxidase-labeled lectins (from Ricinus communis and from Bandeiraea simplicifolia) known to have affinity for alpha- and beta-D-galactose, were strongly reactive with the storage material on frozen sections. The ultrahistochemical and extraction tests showed that the typical granules had a variable reactivity and morphologic characteristics in different cells, probably reflecting different composition. A small number of typical deposits were also observed in the transplanted kidney. This is the first reported case of recurrence of the storage disease in the allograft. Of interest was also the fact that the patient's blood inhibited normal alpha-galactosidase activity, suggesting a possible inhibitor-related mechanism in the pathogenesis of the recurrence. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 PMID:6786101

  5. Performance evaluation of a quasi-microscope for planetary landers

    NASA Technical Reports Server (NTRS)

    Burcher, E. E.; Huck, F. O.; Wall, S. D.; Woehrle, S. B.

    1977-01-01

    Spatial resolutions achieved with cameras on lunar and planetary landers have been limited to about 1 mm, whereas microscopes of the type proposed for such landers could have obtained resolutions of about 1 um but were never accepted because of their complexity and weight. The quasi-microscope evaluated in this paper could provide intermediate resolutions of about 10 um with relatively simple optics that would augment a camera, such as the Viking lander camera, without imposing special design requirements on the camera of limiting its field of view of the terrain. Images of natural particulate samples taken in black and white and in color show that grain size, shape, and texture are made visible for unconsolidated materials in a 50- to 500-um size range. Such information may provide broad outlines of planetary surface mineralogy and allow inferences to be made of grain origin and evolution. The mineralogical descriptions of single grains would be aided by the reflectance spectra that could, for example, be estimated from the six-channel multispectral data of the Viking lander camera.

  6. Microscopic dynamics of synchronization in driven colloids

    PubMed Central

    Juniper, Michael P.N.; Straube, Arthur V.; Besseling, Rut; Aarts, Dirk G.A.L.; Dullens, Roel P.A.

    2015-01-01

    Synchronization of coupled oscillators has been scrutinized for over three centuries, from Huygens' pendulum clocks to physiological rhythms. One such synchronization phenomenon, dynamic mode locking, occurs when naturally oscillating processes are driven by an externally imposed modulation. Typically only averaged or integrated properties are accessible, leaving underlying mechanisms unseen. Here, we visualize the microscopic dynamics underlying mode locking in a colloidal model system, by using particle trajectories to produce phase portraits. Furthermore, we use this approach to examine the enhancement of mode locking in a flexible chain of magnetically coupled particles, which we ascribe to breathing modes caused by mode-locked density waves. Finally, we demonstrate that an emergent density wave in a static colloidal chain mode locks as a quasi-particle, with microscopic dynamics analogous to those seen for a single particle. Our results indicate that understanding the intricate link between emergent behaviour and microscopic dynamics is key to controlling synchronization. PMID:25994921

  7. Operating microscope, microsurgical instruments and microsutures.

    PubMed

    Chacha, P B

    1979-10-01

    A comprehensive knowledge of operating microscope, microsurgical instruments and microsutures is most essential for any beginner in this field. Magnification provided by an operation microscope is higher and variable to suit microsurgical procedures. Although zoom magnification and focussing are preferable for convenience, microscopes with manual controls can be used for clinical and experimental work. A beam splitter and camera equipment are essential accessories. Microsurgical instruments are delicate and expensive and must be bought with discretion and carefully protected. Fine dissecting forceps, needle holder, microscissors, microvascular clamps and clips and fine haemostats are the only essential instruments. Others are optional. Microsutures form the most expensive part of the microsurgical setup. 10-0polyamide suture mounted on a curved round bodied needle of 4 or 5 mm length is adequate for virtually all clinical and experimental microsurgical work. PMID:539800

  8. Macroscopic model of scanning force microscope

    DOEpatents

    Guerra-Vela, Claudio; Zypman, Fredy R.

    2004-10-05

    A macroscopic version of the Scanning Force Microscope is described. It consists of a cantilever under the influence of external forces, which mimic the tip-sample interactions. The use of this piece of equipment is threefold. First, it serves as direct way to understand the parts and functions of the Scanning Force Microscope, and thus it is effectively used as an instructional tool. Second, due to its large size, it allows for simple measurements of applied forces and parameters that define the state of motion of the system. This information, in turn, serves to compare the interaction forces with the reconstructed ones, which cannot be done directly with the standard microscopic set up. Third, it provides a kinematics method to non-destructively measure elastic constants of materials, such as Young's and shear modules, with special application for brittle materials.

  9. Mars Life? - Microscopic Tube-like Structures

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This electron microscope image is a close-up of the center part of photo number S96-12301. While the exact nature of these tube-like structures is not known, one interpretation is that they may be 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.

  10. Universal tool microscope remanufacture based on CCD

    NASA Astrophysics Data System (ADS)

    Kang, Jian; Hu, Zhongxiang; Zhang, Xunming; Zhang, Jiaying

    2006-02-01

    To overcome the drawback of traditional universal tool microscopes, a remanufacturing scheme based on charge coupled devices (CCD) is proposed. In this paper, the remanufacturing of old tool microscopes is replaced gradually by CCD and grating ruler and the development of a novel measuring system designed to directly analyze image of the screw to be measured is discussed. For the analysis of image, such novel image processing methods as adaptive switching median (ASM) filter and edge detection based on the modified Sobel operator are designed. For the line detection algorithm, HOUGH transform also is used to measure the screw parameter. Experiments on screw images demonstrate that the scheme of remanufactured universal tool microscope is of feasibility and the proposed measurement is of validity.

  11. CHAMP - Camera, Handlens, and Microscope Probe

    NASA Technical Reports Server (NTRS)

    Mungas, G. S.; Beegle, L. W.; Boynton, J.; Sepulveda, C. A.; Balzer, M. A.; Sobel, H. R.; Fisher, T. A.; Deans, M.; Lee, P.

    2005-01-01

    CHAMP (Camera, Handlens And Microscope Probe) is a novel field microscope capable of color imaging with continuously variable spatial resolution from infinity imaging down to diffraction-limited microscopy (3 micron/pixel). As an arm-mounted imager, CHAMP supports stereo-imaging with variable baselines, can continuously image targets at an increasing magnification during an arm approach, can provide precision range-finding estimates to targets, and can accommodate microscopic imaging of rough surfaces through a image filtering process called z-stacking. Currently designed with a filter wheel with 4 different filters, so that color and black and white images can be obtained over the entire Field-of-View, future designs will increase the number of filter positions to include 8 different filters. Finally, CHAMP incorporates controlled white and UV illumination so that images can be obtained regardless of sun position, and any potential fluorescent species can be identified so the most astrobiologically interesting samples can be identified.

  12. CHAMP (Camera, Handlens, and Microscope Probe)

    NASA Technical Reports Server (NTRS)

    Mungas, Greg S.; Boynton, John E.; Balzer, Mark A.; Beegle, Luther; Sobel, Harold R.; Fisher, Ted; Klein, Dan; Deans, Matthew; Lee, Pascal; Sepulveda, Cesar A.

    2005-01-01

    CHAMP (Camera, Handlens And Microscope Probe)is a novel field microscope capable of color imaging with continuously variable spatial resolution from infinity imaging down to diffraction-limited microscopy (3 micron/pixel). As a robotic arm-mounted imager, CHAMP supports stereo imaging with variable baselines, can continuously image targets at an increasing magnification during an arm approach, can provide precision rangefinding estimates to targets, and can accommodate microscopic imaging of rough surfaces through a image filtering process called z-stacking. CHAMP was originally developed through the Mars Instrument Development Program (MIDP) in support of robotic field investigations, but may also find application in new areas such as robotic in-orbit servicing and maintenance operations associated with spacecraft and human operations. We overview CHAMP'S instrument performance and basic design considerations below.

  13. Microscopic dynamics of synchronization in driven colloids.

    PubMed

    Juniper, Michael P N; Straube, Arthur V; Besseling, Rut; Aarts, Dirk G A L; Dullens, Roel P A

    2015-01-01

    Synchronization of coupled oscillators has been scrutinized for over three centuries, from Huygens' pendulum clocks to physiological rhythms. One such synchronization phenomenon, dynamic mode locking, occurs when naturally oscillating processes are driven by an externally imposed modulation. Typically only averaged or integrated properties are accessible, leaving underlying mechanisms unseen. Here, we visualize the microscopic dynamics underlying mode locking in a colloidal model system, by using particle trajectories to produce phase portraits. Furthermore, we use this approach to examine the enhancement of mode locking in a flexible chain of magnetically coupled particles, which we ascribe to breathing modes caused by mode-locked density waves. Finally, we demonstrate that an emergent density wave in a static colloidal chain mode locks as a quasi-particle, with microscopic dynamics analogous to those seen for a single particle. Our results indicate that understanding the intricate link between emergent behaviour and microscopic dynamics is key to controlling synchronization. PMID:25994921

  14. Differential optoacoustic absorption detector

    NASA Technical Reports Server (NTRS)

    Shumate, M. S. (Inventor)

    1978-01-01

    A differential optoacoustic absorption detector employed two tapered cells in tandem or in parallel. When operated in tandem, two mirrors were used at one end remote from the source of the beam of light directed into one cell back through the other, and a lens to focus the light beam into the one cell at a principal focus half way between the reflecting mirror. Each cell was tapered to conform to the shape of the beam so that the volume of one was the same as for the other, and the volume of each received maximum illumination. The axes of the cells were placed as close to each other as possible in order to connect a differential pressure detector to the cells with connecting passages of minimum length. An alternative arrangement employed a beam splitter and two lenses to operate the cells in parallel.

  15. Compact Microscope Imaging System with Intelligent Controls

    NASA Technical Reports Server (NTRS)

    McDowell, Mark

    2004-01-01

    The figure presents selected views of a compact microscope imaging system (CMIS) that includes a miniature video microscope, a Cartesian robot (a computer- controlled three-dimensional translation stage), and machine-vision and control subsystems. The CMIS was built from commercial off-the-shelf instrumentation, computer hardware and software, and custom machine-vision software. The machine-vision and control subsystems include adaptive neural networks that afford a measure of artificial intelligence. The CMIS can perform several automated tasks with accuracy and repeatability . tasks that, heretofore, have required the full attention of human technicians using relatively bulky conventional microscopes. In addition, the automation and control capabilities of the system inherently include a capability for remote control. Unlike human technicians, the CMIS is not at risk of becoming fatigued or distracted: theoretically, it can perform continuously at the level of the best human technicians. In its capabilities for remote control and for relieving human technicians of tedious routine tasks, the CMIS is expected to be especially useful in biomedical research, materials science, inspection of parts on industrial production lines, and space science. The CMIS can automatically focus on and scan a microscope sample, find areas of interest, record the resulting images, and analyze images from multiple samples simultaneously. Automatic focusing is an iterative process: The translation stage is used to move the microscope along its optical axis in a succession of coarse, medium, and fine steps. A fast Fourier transform (FFT) of the image is computed at each step, and the FFT is analyzed for its spatial-frequency content. The microscope position that results in the greatest dispersal of FFT content toward high spatial frequencies (indicating that the image shows the greatest amount of detail) is deemed to be the focal position.

  16. Biological imaging with a neutron microscope

    SciTech Connect

    Cremer, J.T.; Piestrup, M.A.; Gary, C.K.; Pantell, R.H.; Glinka, C.J.

    2004-07-19

    A simple microscope employing a compound refractive lens (CRL) composed of 100 biconcave lenses was used to image a biological sample with a 9.4x magnification using 10 A ring cold neutrons. The microscope's resolution, 0.5 mm, was primarily determined by the neutron detector 5.0 mm pixel size. Unlike previous work the CRL's field of view was large (44 mm) and increased as the distance between the exit of neutron-waveguide and the specimen decreased. Short source-to-specimen distances allowed the 1.2-cm-diam CRL to view a biological sample with this field of view.

  17. Microscopic treatment of solute trapping and drag

    NASA Astrophysics Data System (ADS)

    Humadi, Harith; Hoyt, J. J.; Provatas, Nikolas

    2016-01-01

    The long wavelength limit of a recent microscopic phase-field crystal (PFC) theory of a binary alloy mixture is used to derive an analytical approximation for the segregation coefficient as a function of the interface velocity, and relate it to the two-point correlation function of the liquid and the thermodynamic properties of solid and liquid phases. Our results offer the first analytical derivation of solute segregation from a microscopic model, and support recent molecular dynamics and numerical PFC simulations. Our results also provide an independent framework, motivated from classical density functional theory, from which to elucidate the fundamental nature of solute drag, which is still highly contested in the literature.

  18. Atomic sputtering in the analytical electron microscope

    SciTech Connect

    Bradley, C.R.; Zaluzec, N.J.

    1988-08-01

    The advent of UHV medium voltage electron microscopes has brought the microanalyst to a regime of operating conditions in which electron beam induced damage can now be introduced to metallic specimens of medium to high atomic number. We report upon calculations of electron beam induced atomic sputtering which will have bearing upon the next generation of medium voltage analytical electron microscopes. The cross-section calculations reported herein have been completed for all solid elements of the periodic table for incident electron energies up to 1.5 MeV. All computer codes needed to duplicate these computations are available through the EMMPDL. 12 refs., 2 figs., 1 tab.

  19. Multiphoton cryo microscope with sample temperature control

    NASA Astrophysics Data System (ADS)

    Breunig, H. G.; Uchugonova, A.; König, K.

    2013-02-01

    We present a multiphoton microscope system which combines the advantages of multiphoton imaging with precise control of the sample temperature. The microscope provides online insight in temperature-induced changes and effects in plant tissue and animal cells with subcellular resolution during cooling and thawing processes. Image contrast is based on multiphoton fluorescence intensity or fluorescence lifetime in the range from liquid nitrogen temperature up to +600°C. In addition, micro spectra from the imaged regions can be recorded. We present measurement results from plant leaf samples as well as Chinese hamster ovary cells.

  20. An innovative approach in microscopic endodontics.

    PubMed

    Mittal, Sunandan; Kumar, Tarun; Sharma, Jyotika; Mittal, Shifali

    2014-05-01

    The introduction of the dental operating microscope was a turning point in the history of dentistry. It triggered a rapid transition from the conventional world of macro-dentistry to the precise, detailed world of micro-dentistry. However, working at these higher-power magnifications brings the clinician into the realm where even slight hand movements are disruptive. Physiologic hand tremor is a problem resulting in difficulty in mouth mirror placement. Hence, in this paper, a new instrument was designed to overcome the drawback of hand tremors during microscopic endodontics. PMID:24944459

  1. Renewable liquid reflection grating

    DOEpatents

    Ryutov, Dmitri D.; Toor, Arthur

    2003-10-07

    A renewable liquid reflection grating. Electrodes are operatively connected to a conducting liquid in an arrangement that produces a reflection grating and driven by a current with a resonance frequency. In another embodiment, the electrodes create the grating by a resonant electrostatic force acting on a dielectric liquid.

  2. Critically Reflective Leadership

    ERIC Educational Resources Information Center

    Cunningham, Christine L.

    2012-01-01

    Critical Reflective Practice (CRP) has a proven reputation as a method for teacher-researchers in K-12 classrooms, but there have been few published examples of this method being used to document school leaders' work-based practice. This paper outlines adaptations made by the author from an original CRP method to a Critically Reflective Leadership…

  3. Transparencies and Reflections.

    ERIC Educational Resources Information Center

    Hubbard, Guy

    1999-01-01

    Discusses the use of perspective, or showing things as the human eye sees them, when creating reflections and transparencies in works of art. Provides examples of artwork using transparency, reflection, and refraction by M. C. Escher, Richard Estes, and Janet Fish to give students an opportunity to learn about these three art techniques. (CMK)

  4. Earth's Reflection: Albedo

    ERIC Educational Resources Information Center

    Gillette, Brandon; Hamilton, Cheri

    2011-01-01

    When viewing objects of different colors, you might notice that some appear brighter than others. This is because light is reflected differently from various surfaces, depending on their physical properties. The word "albedo" is used to describe how reflective a surface is. The Earth-atmosphere has a combined albedo of about 30%, a number that is…

  5. Engaging in Retrospective Reflection

    ERIC Educational Resources Information Center

    Brevig, Laurey

    2006-01-01

    Reflection is a powerful means to involve readers actively in gaining new insights about texts and themselves as readers. This article relates the story of three fifth-grade girls engaged in metacognitive inquiry within a classroom book club group. The use of exploratory talk and reflection illustrate how the girls constructed meaning and deepened…

  6. Reflecting Random Flights

    NASA Astrophysics Data System (ADS)

    De Gregorio, Alessandro; Orsingher, Enzo

    2015-09-01

    We consider random flights in reflecting on the surface of a sphere with center at the origin and with radius R, where reflection is performed by means of circular inversion. Random flights studied in this paper are motions where the orientation of the deviations are uniformly distributed on the unit-radius sphere . We obtain the explicit probability distributions of the position of the moving particle when the number of changes of direction is fixed and equal to . We show that these distributions involve functions which are solutions of the Euler-Poisson-Darboux equation. The unconditional probability distributions of the reflecting random flights are obtained by suitably randomizing n by means of a fractional-type Poisson process. Random flights reflecting on hyperplanes according to the optical reflection form are considered and the related distributional properties derived.

  7. Two-dimension lateral shearing interferometry for microscope objective wavefront metrology

    NASA Astrophysics Data System (ADS)

    Liu, Zhixiang; Xing, Tingwen; Jiang, Yadong; Lv, Baobin; Xu, Fuchao

    2014-11-01

    Lateral shearing interferometry was an attractive technique to measure the wavefront aberration of high numerical aperture microscope objective lens. A two-dimension lateral shearing interferometer based on chessboard grating was designed for microscope objective wavefront metrology. By positioning the chessboard grating at the Talbot distance of the objective focal plane, the wavefront was divided and sheared in two-dimension. By applying two-dimensional Fourier transform method and differential Zernike polynomial fitting, Zernike coefficients of the wavefront were obtained. A 10x, NA0.25 microscope objective was measured at 632.8nm wavelength, the results showed that the wavefront of the objective was 0.755λ PV, 0.172λ RMS, the repeatability(3σ) of RMS at random grating position was 2.3mλ, the repeatability(3σ) of Z5 to Z36 at random grating position were better than 17mλ.

  8. Reflecting on Čerenkov reflections

    NASA Astrophysics Data System (ADS)

    Fargion, D.; Gaug, M.; Oliva, P.

    2008-05-01

    MAGIC, as well as HESS and VERITAS, is a Čerenkov Telescope unveiling γ-ray sources above 60 GeV at vertical within noisy (hadronic) airshowering sky. These telescopes while facing the horizons may reveal rarest blazing UHECR as well as far fluorescence tails of downward PeV-EeV hadronic airshowers. Few of these inclined airshowers blazing on axis are spread by the geomagnetic field into twin spots. These twin flashes and their morphology may tag the UHECR origination site. There is a rich window of such reflecting Čerenkov lights visible by Telescopes on top of Mountains as MAGIC (and partially VERITAS): the reflections from the nearby ground (possibly enhanced by rain or snow, ice white cover), from the Sea and from the cloudy sky; in particular, these cloudy sheets may lay above or below the observer. MAGIC looking downward to the clouds or the snow, may well reveal blazing Moliere disks diffusing Čerenkov spots (few events per night). Because of geomagnetic forces and splitting of the inclined air-shower, one should reveal for the first time (at tens PeV or above) Čerenkov airshowers whose flashes are skimming the MAGIC nearby Sea and opened into twin spots. Their morphology may tag the UHECR origination, its consequent cross-section and composition. Magic telescopes looking upward into cloudy sky may observe very rare up-going UHE Tau, originated by UHE PeVs neutrinos skimming earth, air-showering into sky, reflecting into clouds. In particular Glashow resonant antineutrinos electron hitting into Earth electrons may lead to gauged boson W-, whose decay (inside the Earth) may produce a τ + bar nuτ [3], which later escape and decay in air is producing Čerenkov lights; these flashes may blaze into the clouds above MAGIC as upward dot spots. The Magic energy threshold for such UHE Neutrinos showers rises to PeV values. EeV UHE tau neutrinos by guaranteed GZK UHECR secondaries [6, 16], via the muon-tau flavor mixing, may skim the Earth, produce UHE tau

  9. Evaluation of reflectance confocal microscopy in dermatophytosis.

    PubMed

    Hui, Dai; Xue-cheng, Sun; Ai-e, Xu

    2013-03-01

    Traditional diagnostic testing for dermatophyte infection currently requires skin scraping for light microscopy and/or fungal culture or skin biopsy. Immunofluorescent microscopy can also be used with calcofluor stain. All of these tests can be time-consuming to perform, require a waiting period for results and are invasive. This study aimed to define the in vivo reflectance confocal microscopy (RCM) features of superficial cutaneous fungal infections and to analyse concordance with microscopic examination. Totally, 45 patients, who were diagnosed with superficial cutaneous fungal infections according to the positive result of microscopic examination, were enrolled in this study. We selected three typical lesions examined by RCM, and then recorded the results. In the patients with the tinea manus and pedis, mycelium in stratum corneum was found by the RCM in 14 of 22 patients (14/22; 63.64%). In the patients with the tinea cruris, mycelium in stratum corneum was found by the RCM in 19 of 23 patients (19/23; 82.61%). RCM seems to be useful for microscopic evaluation of mycelium features and may have a scientific value in study of superficial cutaneous fungal infections. PMID:22963376

  10. Science 101: How Does an Electron Microscope Work?

    ERIC Educational Resources Information Center

    Robertson, Bill

    2013-01-01

    Contrary to popular opinion, electron microscopes are not used to look at electrons. They are used to look for structure in things that are too small to observe with an optical microscope, or to obtain images that are magnified much more than is obtainable with an optical microscope. To understand how electron microscopes work, it will help to go…

  11. Miniature self-contained vacuum compatible electronic imaging microscope

    DOEpatents

    Naulleau, Patrick P.; Batson, Phillip J.; Denham, Paul E.; Jones, Michael S.

    2001-01-01

    A vacuum compatible CCD-based microscopic camera with an integrated illuminator. The camera can provide video or still feed from the microscope contained within a vacuum chamber. Activation of an optional integral illuminator can provide light to illuminate the microscope subject. The microscope camera comprises a housing with a objective port, modified objective, beam-splitter, CCD camera, and LED illuminator.

  12. Scientific data processing for the MICROSCOPE space experiment

    NASA Astrophysics Data System (ADS)

    Hardy, Emilie; Metris, Gilles; Santos Rodrigues, Manuel; Touboul, Pierre; Chhun, Ratana; Baghi, Quentin; Berge, Joel

    The MICROSCOPE space mission aims at testing the Equivalence Principle, which states that the acceleration of a test object due to gravitation is independent of its mass and internal composition. The Equivalence Principle is at the basis of General Relativity and has been tested on-ground with a record accuracy of a few 10(-13) . However, most theories for the unification of the gravitation with the three other fundamental interactions predict that it will be violated at a level 10(-18) -10(-13) . This range cannot be reached on Earth because of the numerous perturbations in the terrestrial environment. Being performed in space, the MICROSCOPE experiment will be able to overcome these limitations in order to test the Equivalence Principle with an accuracy of 10(-15) . The instrument will be embarked on board a drag-free microsatellite orbiting the Earth, and consists in a differential electrostatic accelerometer composed of two cylindrical test masses made of different materials. The position of the masses is detected thanks to capacitive sensors, while control loops with electrostatic actuation keep them concentric, so that they both are submitted to the same gravitational field. The electrostatic acceleration applied to the masses to maintain them relatively motionless are measured and will demonstrate a violation of the Equivalence Principle if found unequal. The potential Equivalence Principle violation signal is expected at a well identified frequency, f _{EP}. However, the raw measurement is impacted by systematic instrumental errors, which are calibrated in-orbit during dedicated sessions. The data processing therefore includes the correction of the measurement in order to reduce the contribution of these errors at f _{EP}. Other perturbations must be considered during the data analysis: numerical effects arise from the finite time span of the measurement. A procedure have thus been determined in order to extract the Equivalence Principle violation parameter

  13. Diffuse reflection coefficient of a stratified sea.

    PubMed

    Haltrin, V I

    1999-02-20

    A differential equation of a Riccati type for the diffuse reflection coefficient of a stratified sea is proposed. For a homogeneous sea with arbitrary inherent optical properties this equation is solved analytically. For an inhomogeneous sea it is solved approximately for any arbitrary stratification. The resulting equation expresses the diffuse reflection coefficient of the sea through vertical profiles of absorption and backscattering coefficients, bottom albedo, and sea depth. The results of calculations with this equation are compared with Monte Carlo computations. It was found that the precision of this approach is in the range of 15%. PMID:18305694

  14. Bacterial differentiation.

    PubMed

    Shapiro, L; Agabian-Keshishian, N; Bendis, I

    1971-09-01

    The foregoing studies are intended to define a differentiation process and to permit genetic access to the mechanisms that control this process. In order to elucidate the basic mechanisms whereby a cell dictates its own defined morphogenic changes, we have found it helpful to study an organism that can be manipulated both biochemically and genetically. We have attempted to develop the studies initiated by Poindexter,Stove and Stanier, and Schmidt and Stanier (16, 17, 20) with the Caulobacter genus so that these bacteria can serve as a model system for prokaryotic differentiation. The Caulobacter life cycle, defined in synchronously growing cultures, includes a sequential series of morphological changes that occur at specific times in the cycle and at specific locations in the cell. Six distinct cellular characteristics, which are peculiar to these bacteria, have been defined and include (i) the synthesis of a polar organelle which may be membranous (21-23), (ii) a satellite DNA in the stalked cell (26), (iii) pili to which RNA bacteriophage specifically adsorb (16, 33), (iv) a single polar flagellum(17), (v) a lipopolysaccharide phage receptor site (27), and (vi) new cell wall material at the flagellated pole of the cell giving rise to a stalk (19, 20). Cell division, essential for the viability of the organism, is dependent on the irreversible differentiation of a flagellated swarmer cell to a mature stalked cell. The specific features of the Caulobacter system which make it a system of choice for studies of the control of sequential events resulting in cellular differentiation can be summarized as follows. 1) Cell populations can be synchronized, and homogeneous populations at each stage in the differentiation cycle can thus be obtained. 2) A specific technique has been developed whereby the progress of the differentiation cycle can be accurately measured by adsorption of labeled RNA phage or penetration of labeled phage DNA into specific cell forms. This

  15. Separation of the Microscopic and Macroscopic Domains

    ERIC Educational Resources Information Center

    Van Zandt, L. L.

    1977-01-01

    Examines the possibility of observing interference in quantum magnification experiments such as the celebrated "Schroedinger cat". Uses the possibility of observing interference for separating the realm of microscopic from macroscopic dynamics; estimates the dividing line to fall at system sizes of about 100 Daltons. (MLH)

  16. Vertically aligned nanostructure scanning probe microscope tips

    SciTech Connect

    Guillorn, Michael A.; Ilic, Bojan; Melechko, Anatoli V.; Merkulov, Vladimir I.; Lowndes, Douglas H.; Simpson, Michael L.

    2006-12-19

    Methods and apparatus are described for cantilever structures that include a vertically aligned nanostructure, especially vertically aligned carbon nanofiber scanning probe microscope tips. An apparatus includes a cantilever structure including a substrate including a cantilever body, that optionally includes a doped layer, and a vertically aligned nanostructure coupled to the cantilever body.

  17. Making a Microscope with Readily Available Materials

    ERIC Educational Resources Information Center

    Vannoni, Maurizio; Buah-Bassuah, Paul K.; Molesini, Giuseppe

    2007-01-01

    The making of microscope devices using inexpensive or recovered materials is demonstrated. Examples of images illustrating the performance of such devices are presented. As a project at the undergraduate level, the task is effective in acquiring familiarity with optical imaging concepts and their practical implementation in the laboratory.…

  18. Formative Assessment Probes: Representing Microscopic Life

    ERIC Educational Resources Information Center

    Keeley, Page

    2011-01-01

    This column focuses on promoting learning through assessment. The author discusses the formative assessment probe "Pond Water," which reveals how elementary children will often apply what they know about animal structures to newly discovered microscopic organisms, connecting their knowledge of the familiar to the unfamiliar through…

  19. Reasoning about Magnetism at the Microscopic Level

    ERIC Educational Resources Information Center

    Cheng, Meng-Fei; Cheng, Yufang; Hung, Shuo-Hsien

    2014-01-01

    Based on our experience of teaching physics in middle and senior secondary school, we have found that students have difficulty in reasoning at the microscopic level. Their reasoning is limited to the observational level so they have problems in developing scientific models of magnetism. Here, we suggest several practical activities and the use of…

  20. First results of a positron microscope

    SciTech Connect

    Van House, J.; Rich, A.

    1988-01-18

    We have constructed a prototype transmission positron microscope (TPM) and taken magnified pictures of various objects with it. Information gained from the prototype TPM has allowed us to predict resolutions achievable in the near future using an upgraded TPM. Applications are discussed.

  1. Schematic Animation of Phoenix's Microscope Station

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on image for animation

    This animation shows the workings of the microscope station of the Microscopy, Electrochemistry and Conductivity Analyzer (MECA) instrument suite of NASA's Phoenix Mars Lander.

    Samples are delivered to the horizontal portion of the sample wheel (yellow) that pokes outside an opening in the box enclosure. The wheel rotates to present the sample to the microscopes. The Optical Microscope (red) can see particles a little smaller than one-tenth the diameter of a human hair. The Atomic Force Microscope (pink) can see particles forty time smaller. The samples are on a variety of substrate surfaces, the small circles on the beveled edge of the sample wheel. For scale, the diameter of the wheel is about 14 centimeters (5.5 inches). Each substrate is a circle 3 millimeters (0.1 inch) in diameter.

    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.

  2. SLAC All Access: X-ray Microscope

    SciTech Connect

    Nelson, Johanna; Liu, Yijin

    2012-08-14

    SLAC physicists Johanna Nelson and Yijin Liu give a brief overview of the X-ray microscope at the Stanford Synchrotron Radiation Lightsource (SSRL) that is helping improve rechargeable-battery technology by letting researchers peek into the inner workings of batteries as they operate.

  3. The Nucleus and the Simple Microscope.

    ERIC Educational Resources Information Center

    Ford, Brian J.

    1982-01-01

    The 150th anniversary of the naming of the nucleus by Robert Brown in 1831 was commemorated by re-creating some of his most important observations using two of his microscopes. Comments on Brown's career and the microtechnique employed during his time are provided. (Author/JN)

  4. The Microscope and Nineteenth Century Education.

    ERIC Educational Resources Information Center

    Milacek, Barbara Roads

    Studied were (1) the evolving use of the microscope in science education, and (2) its relationship to the changing teaching methods, content, and emphases of science courses and to the prevailing philosophies of education of nineteenth century American colleges. To establish the necessary background, the evolution and availability of the…

  5. Towards a Microscopic Understanding of Nucleon Polarizabilities

    NASA Astrophysics Data System (ADS)

    Eichmann, Gernot

    2016-07-01

    We outline a microscopic framework to calculate nucleon Compton scattering from the level of quarks and gluons within the covariant Faddeev approach. We explain the connection with hadronic expansions of the Compton scattering amplitude and discuss the obstacles in maintaining electromagnetic gauge invariance. Finally we give preliminary results for the nucleon polarizabilities.

  6. Miniaturized 3D microscope imaging system

    NASA Astrophysics Data System (ADS)

    Lan, Yung-Sung; Chang, Chir-Weei; Sung, Hsin-Yueh; Wang, Yen-Chang; Chang, Cheng-Yi

    2015-05-01

    We designed and assembled a portable 3-D miniature microscopic image system with the size of 35x35x105 mm3 . By integrating a microlens array (MLA) into the optical train of a handheld microscope, the biological specimen's image will be captured for ease of use in a single shot. With the light field raw data and program, the focal plane can be changed digitally and the 3-D image can be reconstructed after the image was taken. To localize an object in a 3-D volume, an automated data analysis algorithm to precisely distinguish profundity position is needed. The ability to create focal stacks from a single image allows moving or specimens to be recorded. Applying light field microscope algorithm to these focal stacks, a set of cross sections will be produced, which can be visualized using 3-D rendering. Furthermore, we have developed a series of design rules in order to enhance the pixel using efficiency and reduce the crosstalk between each microlens for obtain good image quality. In this paper, we demonstrate a handheld light field microscope (HLFM) to distinguish two different color fluorescence particles separated by a cover glass in a 600um range, show its focal stacks, and 3-D position.

  7. SLAC All Access: X-ray Microscope

    ScienceCinema

    Nelson, Johanna; Liu, Yijin

    2014-06-13

    SLAC physicists Johanna Nelson and Yijin Liu give a brief overview of the X-ray microscope at the Stanford Synchrotron Radiation Lightsource (SSRL) that is helping improve rechargeable-battery technology by letting researchers peek into the inner workings of batteries as they operate.

  8. Acquisition speed comparison of microscope software programs.

    PubMed

    Biehlmaier, Oliver; Hehl, Joachim; Csucs, Gabor

    2011-06-01

    Reliable software is a prerequisite for successful operation of a modern wide field fluorescence microscope. When used for live cell imaging, acquisition speed is of particular interest. This is both because biological processes can be highly-dynamic, and to avoid unnecessary photobleaching and phototoxicity of living samples. This article shows that besides the hardware (microscope) components themselves, the acquisition control software is an important influencing factor of speed performance. We tested and compared the speed performance of five different generic applications (Image-Pro Plus, MetaMorph, Micro-Manager, SlideBook, and Volocity) using typical experimental setups involving a single specific state-of-the-art fluorescence microscope configuration. The test measurements included multichannel experiments, z-stacking, burst acquisition, as well as combinations of these measurements with time-lapse acquisitions. The measured data provided values for guiding the testing and analysis of other microscope systems with similar configurations. Despite the identical hardware settings, significant and surprisingly large speed differences were evident among the various software applications. Additionally, no application was identifiable as the fastest in all tests. Our work pinpoints the importance of the control software in determining a system's "real" maximal imaging speed. The study could serve as basis for further tests, eventually influencing the system selection criteria for speed-sensitive applications. PMID:21604324

  9. Dual-mode optical microscope based on single-pixel imaging

    NASA Astrophysics Data System (ADS)

    Rodríguez, A. D.; Clemente, P.; Tajahuerce, E.; Lancis, J.

    2016-07-01

    We demonstrate an inverted microscope that can image specimens in both reflection and transmission modes simultaneously with a single light source. The microscope utilizes a digital micromirror device (DMD) for patterned illumination altogether with two single-pixel photosensors for efficient light detection. The system, a scan-less device with no moving parts, works by sequential projection of a set of binary intensity patterns onto the sample that are codified onto a modified commercial DMD. Data to be displayed are geometrically transformed before written into a memory cell to cancel optical artifacts coming from the diamond-like shaped structure of the micromirror array. The 24-bit color depth of the display is fully exploited to increase the frame rate by a factor of 24, which makes the technique practicable for real samples. Our commercial DMD-based LED-illumination is cost effective and can be easily coupled as an add-on module for already existing inverted microscopes. The reflection and transmission information provided by our dual microscope complement each other and can be useful for imaging non-uniform samples and to prevent self-shadowing effects.

  10. Spin microscope based on optically detected magnetic resonance

    SciTech Connect

    Berman, Gennady P.; Chernobrod, Boris M.

    2009-11-10

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of impaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  11. Spin microscope based on optically detected magnetic resonance

    SciTech Connect

    Berman, Gennady P.; Chernobrod, Boris M.

    2010-06-29

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  12. Spin microscope based on optically detected magnetic resonance

    SciTech Connect

    Berman, Gennady P.; Chernobrod, Boris M.

    2010-07-13

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  13. Spin microscope based on optically detected magnetic resonance

    SciTech Connect

    Berman, Gennady P.; Chernobrod, Boris M.

    2009-10-27

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  14. Spin microscope based on optically detected magnetic resonance

    DOEpatents

    Berman, Gennady P.; Chernobrod, Boris M.

    2007-12-11

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  15. Weak shock reflection

    NASA Astrophysics Data System (ADS)

    Hunter, John K.; Brio, Moysey

    2000-05-01

    We present numerical solutions of a two-dimensional inviscid Burgers equation which provides an asymptotic description of the Mach reflection of weak shocks. In our numerical solutions, the incident, reflected, and Mach shocks meet at a triple point, and there is a supersonic patch behind the triple point, as proposed by Guderley for steady weak-shock reflection. A theoretical analysis indicates that there is an expansion fan at the triple point, in addition to the three shocks. The supersonic patch is extremely small, and this work is the first time it has been resolved.

  16. GNSS Ocean Reflected Signals

    NASA Astrophysics Data System (ADS)

    Hoeg, P.

    2012-12-01

    Ocean reflected signals from the GNSS satellites (received at low-Earth orbiting satellites, airplanes and fixed mountain locations) describe the ocean surface mean height, waves, roughness, spectral reflectivity and emissivity. The estimated accuracy of the average surface height is of the order of 10 cm for smooth conditions. Thus global observations could be an important new contribution to long-term variations of the ocean mean height as well as the monitoring of ocean mesoscale eddies, which result in sea-height changes much larger than the accuracy of the GNSS technique for reflected signals. The ocean reflected signals can be divided into two set of measurements, 1) high elevation measurements (equal to low incidence angles) and 2) low elevation grazing angle measurements. For the first type the ocean reflection cross-section has a limited extent. The reflected signal is coherent with smaller errors due to ocean waves, sampling rate and the internal processing method of the receiver. For low elevations, the signal reveals the incoherent scatter process at the reflection zone. To quantify the potential of the GNSS signals for determining spectral reflectivity at low elevations, we present ocean reflection GPS measurements from the Haleakala Summit on Maui, Hawaii, revealing the spectral characteristics of both the direct satellite signal and the ocean reflected signal for low elevation angles. The characteristics of the reflected signal depend on the scattering properties of the sea surface and the footprint of the reflection zone. While the footprint size and shape in turn depends on the signal incidence angle, the ocean mean tilt, and the relative velocities of transmitter and receiver to the reflection point. Thus the scattering properties of the sea surface are related to the sea surface roughness. We present the spectral properties of the signals as received by a high precision GPS instrument, simultaneously in both phase-locked mode and open-loop raw

  17. Receptor reserve reflects differential intrinsic efficacy associated with opioid diastereomers.

    PubMed

    Carliss, Richard D S; Keefer, James F; Perschke, Scott; Welch, Sandra; Rich, Thomas C; Weissman, Arthur D

    2009-05-01

    Structure-activity relationships built around receptor binding or cell-based assays are designed to reveal physiochemical differences between ligands. We hypothesized that agonist receptor reserve may provide a unique approach to distinguish structurally-related agonists exhibiting similar functional characteristics. An intracellular calcium activation assay in Chinese Hamster Ovary (CHO) cells expressing cloned human mu-opioid receptors was developed. We examined two isomers exhibiting indistinguishable receptor binding and in vitro potency profiles. Oxymorphone, a clinically-available congener of codeine has at least two active diastereomeric metabolites (6alpha- and 6beta-oxymorphols) found to be similar for mu-opioid receptor binding affinity (K(d) = 15 versus 14 nM) and calcium activation (EC(50) = 22 versus 14 nM). Calcium activation was then inhibited in CHO cells in a concentration-dependent manner using the irreversible mu-opioid receptor antagonist, beta-funaltrexamine (beta-FNA). Under these conditions, approximately 10-fold greater receptor reserve was found for 6alpha-oxymorphol compared to 6beta-oxymorphol. This difference between the oxymorphols corresponded to a rank order of intrinsic efficacy (Emax): DAMGO > oxymorphone = 6alpha-oxymorphol = oxycodone > 6beta-oxymorphol. In addition, 6alpha-oxymorphol exhibited greater relative potency than the 6beta-oxymorphol in mouse tail-flick, hot-plate and phenylquinone writhing antinociceptive assays, regardless of route of administration. Thus the beta-FNA/calcium model provides a novel, cell-based approach to distinguish structurally related mu-opioid agonists, and in the specific case of the oxymorphols, receptor reserve differences provided a means to bridge functional in vitro and in vivo models. PMID:19463265

  18. Through the Looking Glass: One School's Reflection on Differentiation

    ERIC Educational Resources Information Center

    Tieso, Carol

    2004-01-01

    Teachers must deal with a diversity of students' abilities, strengths, and interests in their classrooms while at the same time covering the material, prepping students for standardized tests, and preparing themselves to be "highly qualified." Legislation requiring services for gifted and talented students and the paucity of quality programs for…

  19. Host resistance reflected in differential nematode population structures.

    PubMed

    Viglierchio, D R; Croll, N A

    1968-07-19

    Relative efficiency of host plants to support reproduction of the garlic race of Ditylenchus dipsaci can be partially explained by diflerential population structures. If axenic cultures of callus tissue from onion, white clover, red clover, and alfalfa are arranged in order of decreasing host suitability, the nematode populations are simultaneously arranged in order of increasing maleness. PMID:5657331

  20. Microscopic anthropogenic litter in terrestrial birds from Shanghai, China: Not only plastics but also natural fibers.

    PubMed

    Zhao, Shiye; Zhu, Lixin; Li, Daoji

    2016-04-15

    The level of contamination by microscopic anthropogenic litter (0.5-5mm) in terrestrial ecosystems is not well understood. After chemical digestion in 10% KOH, microscopic anthropogenic litter from the gastrointestinal tracts of 17 terrestrial birds was identified and categorized under a stereomicroscope based on its physical properties and melting tests. In total, 364 items from 16 birds were identified as microscopic anthropogenic litter, ranging in size from 0.5 to 8.5mm. No relationship between plastic load and body condition was found. Natural fibers, plastic fibers and fragmented plastics represented, respectively, 37.4% (136 items), 54.9% (200 items) and 7.7% (28 items) of total litter items. Small sample sizes limited our ability to draw strong conclusions about the metabolism of natural fibers, but the decline in the proportion of natural fibers from the esophagus to stomach to intestine suggested that they may be digestible. Particles smaller than 5mm represented more than 90% of the total number of pollutant items. Particles with colors in the mid-tones and fibrous shapes were overwhelmingly common particles. The results reflect pollution by microscopic anthropogenic litter in the terrestrial ecosystem of the study area. Microscopic natural fibers, which may disperse and adsorb chemical pollutants differently from microplastic and may pose an even greater risk, are in urgent need of further research. PMID:26874248

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  2. A scanning acoustic microscope discriminates cancer cells in fluid

    NASA Astrophysics Data System (ADS)

    Miura, Katsutoshi; Yamamoto, Seiji

    2015-10-01

    Scanning acoustic microscopy (SAM) discriminates lesions in sections by assessing the speed of sound (SOS) or attenuation of sound (AOS) through tissues within a few minutes without staining; however, its clinical use in cytological diagnosis is unknown. We applied a thin layer preparation method to observe benign and malignant effusions using SAM. Although SAM is inferior in detecting nuclear features than light microscopy, it can differentiate malignant from benign cells using the higher SOS and AOS values and large irregular cell clusters that are typical features of carcinomas. Moreover, each single malignant cell exhibits characteristic cytoplasmic features such as a large size, irregular borders and secretory or cytoskeletal content. By adjusting the observation range, malignant cells are differentiated from benign cells easily using SAM. Subtle changes in the functional and structural heterogeneity of tumour cells were pursuable with a different digital data of SAM. SAM can be a useful tool for screening malignant cells in effusions before light microscopic observation. Higher AOS values in malignant cells compared with those of benign cells support the feasibility of a novel sonodynamic therapy for malignant effusions.

  3. Reflections on Miniature Golf.

    ERIC Educational Resources Information Center

    Powell, Nancy Norem; And Others

    1994-01-01

    Describes a transformational geometry project in which groups of students explore symmetry, reflections, translations, rotations, and dilations to design and create one hole of miniature golf large enough to play on. Includes unit plan for transformational geometry. (MKR)

  4. Seasonal soybean crop reflectance

    NASA Technical Reports Server (NTRS)

    Lemaster, E. W. (Principal Investigator); Chance, J. E.

    1983-01-01

    Data are presented from field measurements of 1980 including 5 acquisitions of handheld radiometer reflectance measurements, 7 complete sets of parameters for implementing the Suits mode, and other biophysical parameters to characterize the soybean canopy. LANDSAT calculations on the simulated Brazilian soybean reflectance are included along with data collected during the summer and fall on 1981 on soybean single leaf optical parameters for three irrigation treatments. Tests of the Suits vegetative canopy reflectance model for the full hemisphere of observer directions as well as the nadir direction show moderate agreement for the visible channels of the MSS and poor agreement in the near infrared channel. Temporal changes in the spectral characteristics of the single leaves were seen to occur as a function of maturity which demonstrates that the absorptance of a soybean single leaf is more a function of thetransmittancee characteristics than the seasonally consistent single leaf reflectance.

  5. Andreev reflection in graphene

    NASA Astrophysics Data System (ADS)

    Beenakker, Carlo

    2007-03-01

    Relativity and superconductivity have no common ground in ordinary matter, because the velocity of electrons is only a small fraction of the velocity of light. The unusual band structure of a single layer of carbon atoms (graphene) contains negatively and positively charged particles that move as relativistic electrons and positrons. The electron-like particles in the conduction band can be converted into positron-like particles in the valence band when they are reflected by a superconductor. (The missing charge of 2e enters the superconductor as a Cooper pair.) This interband reflection process can be distinguished from the usual intraband Andreev reflection, because the reflection angle has the opposite sign. A new phenomenology of graphene--superconductor junctions is predicted, including an anomalous scaling of the supercurrent with the length of the junction and the existence of charge-neutral modes propagating along the interface.

  6. Brewster Angle Microscope Investigations of Two Dimensional Phase Transitions

    NASA Astrophysics Data System (ADS)

    Schuman, Adam William

    The liquid-liquid interface is investigated by microscopic and thermodynamic means to image and measure interfacial properties when the system undergoes a two-dimensional (2D) phase transition of a Gibbs monolayer by varying the sample temperature. An in-house Brewster angle microscope (BAM) is constructed to visualize the interface during this transition while a quasi-elastic light scattering technique is used to determine the interfacial tension. These results complement x-ray investigations of the same systems. Evidence of interfacial micro-separated structure, microphases, comes from observations across a hexane-water interface with the inclusion of a long-chain fluorinated alcohol surfactant into the bulk hexane. Microphases take the form of spatially modulated structure to the density of the surfactant as it spans laterally across the interface. The surfactant monolayer exhibits microphase morphology over a range of a couple degrees as the temperature of the system is scanned through the 2D gas-solid phase transition. Microphase structure was observed for heating and cooling the hexane-water system and structural comparisons are given when the temperature step and quench depth of the cooling process is varied. A complete sequence of morphological structure was observed from 2D gas to cluster to labyrinthine stripe to a 2D solid mosaic pattern. Two characteristic length scales emerge giving rise to speculation of an elastic contribution to the standard repulsive and attractive competitive forces stabilizing the microphase. The benefit of BAM to laterally image very thin films across the surface of an interface on the micrometer length scale nicely complements x-ray reflectivity methods that average structural data transverse to the liquid interface on a molecular scale. To properly analyze x-ray reflectivity data, the interface is required to be laterally homogeneous. BAM can sufficiently characterize the interface for this purpose as is done for a Langmuir

  7. Reflectance of aqueous solutions

    NASA Technical Reports Server (NTRS)

    Querry, M. R.

    1972-01-01

    The optical properties and optical constants of water and aqueous solutions were studied to develop an accurate tabulation of graphical representations of the optical constants through a broad spectrum. Manuscripts of articles are presented concerning extinction coefficients, relative specular reflectance, and temperature effect on the water spectrum. Graphs of absolute reflectance, phase shifts, index of refraction, and extinction coefficients for water, heavy water and aqueous solutions are included.

  8. Selectively reflective transparent sheets

    NASA Astrophysics Data System (ADS)

    Waché, Rémi; Florescu, Marian; Sweeney, Stephen J.; Clowes, Steven K.

    2015-08-01

    We investigate the possibility to selectively reflect certain wavelengths while maintaining the optical properties on other spectral ranges. This is of particular interest for transparent materials, which for specific applications may require high reflectivity at pre-determined frequencies. Although there exist currently techniques such as coatings to produce selective reflection, this work focuses on new approaches for mass production of polyethylene sheets which incorporate either additives or surface patterning for selective reflection between 8 to 13 μ m. Typical additives used to produce a greenhouse effect in plastics include particles such as clays, silica or hydroxide materials. However, the absorption of thermal radiation is less efficient than the decrease of emissivity as it can be compared with the inclusion of Lambertian materials. Photonic band gap engineering by the periodic structuring of metamaterials is known in nature for producing the vivid bright colors in certain organisms via strong wavelength-selective reflection. Research to artificially engineer such structures has mainly focused on wavelengths in the visible and near infrared. However few studies to date have been carried out to investigate the properties of metastructures in the mid infrared range even though the patterning of microstructure is easier to achieve. We present preliminary results on the diffuse reflectivity using FDTD simulations and analyze the technical feasibility of these approaches.

  9. Quantum groups, non-commutative differential geometry and applications

    SciTech Connect

    Schupp, P

    1993-12-09

    The topic of this thesis is the development of a versatile and geometrically motivated differential calculus on non-commutative or quantum spaces, providing powerful but easy-to-use mathematical tools for applications in physics and related sciences. A generalization of unitary time evolution is proposed and studied for a simple 2-level system, leading to non-conservation of microscopic entropy, a phenomenon new to quantum mechanics. A Cartan calculus that combines functions, forms, Lie derivatives and inner derivations along general vector fields into one big algebra is constructed for quantum groups and then extended to quantum planes. The construction of a tangent bundle on a quantum group manifold and an BRST type approach to quantum group gauge theory are given as further examples of applications. The material is organized in two parts: Part I studies vector fields on quantum groups, emphasizing Hopf algebraic structures, but also introducing a ``quantum geometric`` construction. Using a generalized semi-direct product construction we combine the dual Hopf algebras A of functions and U of left-invariant vector fields into one fully bicovariant algebra of differential operators. The pure braid group is introduced as the commutant of {Delta}(U). It provides invariant maps A {yields} U and thereby bicovariant vector fields, casimirs and metrics. This construction allows the translation of undeformed matrix expressions into their less obvious quantum algebraic counter parts. We study this in detail for quasitriangular Hopf algebras, giving the determinant and orthogonality relation for the ``reflection`` matrix. Part II considers the additional structures of differential forms and finitely generated quantum Lie algebras -- it is devoted to the construction of the Cartan calculus, based on an undeformed Cartan identity.

  10. Analysis of biological time-lapse microscopic experiment from the point of view of the information theory.

    PubMed

    Štys, Dalibor; Urban, Jan; Vaněk, Jan; Císař, Petr

    2011-06-01

    We report objective analysis of information in the microscopic image of the cell monolayer. The process of transfer of information about the cell by the microscope is analyzed in terms of the classical Shannon information transfer scheme. The information source is the biological object, the information transfer channel is the whole microscope including the camera chip. The destination is the model of biological system. The information contribution is analyzed as information carried by a point to overall information in the image. Subsequently we obtain information reflection of the biological object. This is transformed in the biological model which, in information terminology, is the destination. This, we propose, should be constructed as state transitions in individual cells modulated by information bonds between the cells. We show examples of detected cell states in multidimensional state space. This space is reflected as colour channel intensity phenomenological state space. We have also observed information bonds and show examples of them. PMID:25478628

  11. Analysis of biological time-lapse microscopic experiment from the point of view of the information theory.

    PubMed

    Stys, Dalibor; Urban, Jan; Vanek, Jan; Císar, Petr

    2010-07-01

    We report objective analysis of information in the microscopic image of the cell monolayer. The process of transfer of information about the cell by the microscope is analyzed in terms of the classical Shannon information transfer scheme. The information source is the biological object, the information transfer channel is the whole microscope including the camera chip. The destination is the model of biological system. The information contribution is analyzed as information carried by a point to overall information in the image. Subsequently we obtain information reflection of the biological object. This is transformed in the biological model which, in information terminology, is the destination. This, we propose, should be constructed as state transitions in individual cells modulated by information bonds between the cells. We show examples of detected cell states in multidimensional state space reflected in space an colour channel intensity phenomenological state space. We have also observed information bonds and show examples of them. PMID:20194026

  12. Defining Reflection: Another Look at John Dewey and Reflective Thinking.

    ERIC Educational Resources Information Center

    Rodgers, Carol

    2002-01-01

    Examines four criteria that characterize John Dewey's view of reflective thought: reflection as a meaning-making process; reflection as a systematic, rigorous, disciplined way of thinking with its roots in scientific inquiry; reflection needs to happen in community, in interaction with others; and reflection requires attitudes that value the…

  13. Analytical elimination of substrate backside reflections from reflectance measurements.

    PubMed

    Wilbrandt, Steffen; Stenzel, Olaf

    2016-09-01

    An analytical approach to eliminate substrate backside reflections from measured reflectance of an unknown optical coating has been deducted. Thereby, measured transmittance, reflectance, and backside reflectance of the coating and transmittance and reflectance of the uncoated substrate at the desired angle of incidence and polarization state are required as input data. In the underlying theory, layer and substrate materials may be absorbing. PMID:27607274

  14. Design, Fabrication and Testing of Multilayer Coated X-Ray Optics for the Water Window Imaging X-Ray Microscope

    NASA Technical Reports Server (NTRS)

    Spencer, Dwight C.

    1996-01-01

    Hoover et. al. built and tested two imaging Schwarzschild multilayer microscopes. These instruments were constructed as prototypes for the "Water Window Imaging X-Ray Microscope," which is a doubly reflecting, multilayer x-ray microscope configured to operate within the "water window." The "water window" is the narrow region of the x-ray spectrum between the K absorption edges of oxygen (lamda = 23.3 Angstroms) and of carbon (lamda = 43.62 Angstroms), where water is relatively highly transmissive and carbon is highly absorptive. This property of these materials, thus permits the use of high resolution multilayer x-ray microscopes for producing high contrast images of carbon-based structures within the aqueous physiological environments of living cells. We report the design, fabrication and testing of multilayer optics that operate in this regime.

  15. Commissioning of the PRIOR proton microscope

    DOE PAGESBeta

    Varentsov, D.; Antonov, O.; Bakhmutova, A.; Barnes, C. W.; Bogdanov, A.; Danly, C. R.; Efimov, S.; Endres, M.; Fertman, A.; Golubev, A. A.; et al

    2016-02-18

    Recently, a new high energy proton microscopy facility PRIOR (Proton Microscope for FAIR Facility for Anti-proton and Ion Research) has been designed, constructed, and successfully commissioned at GSI Helmholtzzentrum für Schwerionenforschung (Darmstadt, Germany). As a result of the experiments with 3.5–4.5 GeV proton beams delivered by the heavy ion synchrotron SIS-18 of GSI, 30 μm spatial and 10 ns temporal resolutions of the proton microscope have been demonstrated. A new pulsed power setup for studying properties of matter under extremes has been developed for the dynamic commissioning of the PRIOR facility. This study describes the PRIOR setup as well asmore » the results of the first static and dynamic protonradiography experiments performed at GSI.« less

  16. Energy functions for rubber from microscopic potentials

    NASA Astrophysics Data System (ADS)

    Johal, A. S.; Dunstan, D. J.

    2007-04-01

    The finite deformation theory of rubber and related materials is based on energy functions that describe the macroscopic response of these materials under deformation. Energy functions and elastic constants are here derived from a simple microscopic (ball-and-spring) model. Exact uniaxial force-extension relationships are given for Hooke's Law and for the thermodynamic entropy-based microscopic model using the Gaussian and the inverse Langevin statistical approximations. Methods are given for finding the energy functions as expansions of tensor invariants of deformation, with exact solutions for functions that can be expressed as expansions in even powers of the extension. Comparison with experiment shows good agreement with the neo-Hookean energy function and we show how this derives directly from the simple Gaussian statistical model with a small modification.

  17. Microscopic treatment of solute trapping and drag.

    PubMed

    Humadi, Harith; Hoyt, J J; Provatas, Nikolas

    2016-01-01

    The long wavelength limit of a recent microscopic phase-field crystal (PFC) theory of a binary alloy mixture is used to derive an analytical approximation for the segregation coefficient as a function of the interface velocity, and relate it to the two-point correlation function of the liquid and the thermodynamic properties of solid and liquid phases. Our results offer the first analytical derivation of solute segregation from a microscopic model, and support recent molecular dynamics and numerical PFC simulations. Our results also provide an independent framework, motivated from classical density functional theory, from which to elucidate the fundamental nature of solute drag, which is still highly contested in the literature. PMID:26871012

  18. A quantum gas microscope for ytterbium atoms

    NASA Astrophysics Data System (ADS)

    Takahashi, Yoshiro

    2016-05-01

    In this talk, I report on the development of a quantum gas microscope for ytterbium (Yb) atoms. By using a dual molasses technique in which 399 nm molasses beams of the broad singlet transition are applied for fluorescence imaging and 556 nm molasses beams of the narrow intercombination transition are applied for cooling during the imaging, we successfully demonstrate site-resolved imaging of individual bosonic 174 Yb atoms in a two-dimensional optical lattice with a lattice constant of 266 nm.We also apply a high resolution laser spectroscopy using the ultranarrow intercombination transition between the 1 S0 and 3 P2 states to manipulate an atom distribution in an optical lattice. We expect the demonstrated technique will similarly work for other isotopes of Yb atoms. We are also developing a different mode of an Yb quantum gas microscope.

  19. Center-of-Excellence: Microlaser microscope

    NASA Astrophysics Data System (ADS)

    Webb, R. H.

    This Center-of-Excellence grant has supported the development of an imaging system based on microlaser arrays. In the second year of the grant, we dealt with the slow delivery of new microlaser arrays by developing a new approach to the idea of all-solid-state confocal microscopy. One solution was moderately successful, and the other has produced the first microscope that is electronically switchable from confocal to non-confocal. We think this may be a useful alternative to the final design. This report thus discloses patentable material. We describe first the central Microlaser Microscope project, then we will touch briefly on the other projects of the Center. The publications are primarily those of the smaller projects, though no longer exclusively so. The appendix includes some of the publications.

  20. Specular Microscopic Features of Corneal Endothelial Vacuolation

    PubMed Central

    Kanavi, Mozhgan Rezaei; Javadi, Mohammad-Ali; Chamani, Tahereh

    2011-01-01

    Purpose To introduce a specular microscopic reference image for endothelial vacuolation in donated corneas. Methods Two corneas from a donor with diffuse, round to oval dark areas at the endothelial level on slit lamp biomicroscopy and one normal-appearing donor cornea underwent specular microscopy, histopathologic evaluation and transmission electron microscopy. Results Specular microscopy of the two corneas with abnormal-looking endothelium revealed large numbers of dark, round to oval structures within the endothelium in favor of endothelial vacuolation. Light microscopy disclosed variable sized cyst-like structures within the cytoplasm. Transmission electron microscopy showed electron-lucent and relatively large-sized intracytoplasmic vacuoles. These features were not observed in the endothelium of the normal cornea. Conclusion The specular microscopic features of endothelial vacuolation in donated corneas were confirmed by light microscopy and transmission electron microscopy, therefore the specular image may be proposed as a reference to eye banks. PMID:22454699